A DEVICE, A SYSTEM AND METHOD FOR RESURRECTION OF A YARN BREAKAGE IN A RING SPINNING MACHINE

Abstract

 A device (31) for automated resurrection of a yarn breakage in a ring spinning machine (1), the device (31) comprising a robot arrangement (51) for carrying out a plurality of work steps for resurrection of a yarn breakage and a transportation arrangement (141) with a drive (142) for moving the device (31) along the ring spinning machine (1). The robot arrangement (51) comprises a yarn capturing unit (101) having a yarn attracting and picking mechanism (104) for attracting and picking the yarn end from the cop (7), a yarn holding mechanism (108) for holding the picked yarn, and a moving and positioning mechanism (102) for moving and positioning the yarn attracting and picking mechanism (104). The device (31) further comprises a yarn threading unit (121) for threading the yarn (8) into the traveller (11), having a yarn holding mechanism (127), a traveller positioning mechanism (124) and a moving and positioning mechanism (122) for moving and positioning the yarn holding mechanism (127) and the traveller positioning mechanism (124).

Description

[0001] The present subject matter described herein, in general, relates to the field of producing textile yarn, and more particularly to a device, a system and a method for automatic resurrection, i.e. restoration or rectifying, of a yarn breakage in a ring spinning machine.

[0002] Ring spinning is a method of spinning fibres, such as cotton, flax, wool, synthetic or a mixture thereof, to make a textile yarn. Ring spinning machines have means for spinning a yarn from a roving supplied by a fly frame, also called roving frame, and for winding said yarn onto a cop by means of a revolving spindle. Ring spinning machines are well known in the prior-art. The document US 3905187 A for example discloses such a ring spinning machine.

[0003] A ring spinning machine, also called ring spinning frame, contains a plurality of spinning positions in which a yarn is spun from a roving. Each spinning position comprises a roving bobbin which is fastened on a bobbin holder. The roving is produced in a roving machine, also called roving frame, from a sliver.

[0004] The roving is transported from the roving bobbin trough a drafting arrangement in which the roving is drafted into a fibre strand. The drafted roving leaves the drafting arrangement through delivery rollers in form of a fibre strand and is transported towards a rotating/revolving spindle. Between the nip of the delivery rollers and the spindle the fibre strand is twisted into a yarn. The transport direction of the fibre material, i.e. the process direction of the fibre material is top down.

[0005] Between the delivery rollers and the spindle yarn guiding elements can be arranged such as a lappet hook and/or a balloon control ring. In process direction the lappet hook is arranged subsequent to the delivery rollers and the balloon control ring - if present - is arranged subsequent to the lappet hook.

[0006] On the spindle a tube is arranged on which the windings of the produced yarn are deposited. The tube together with the yarn windings forms the so called spinning cop, also called cop package or simply cop. The tube in particular is put on the spindle.

[0007] The spindle is surrounded by a traveller guiding ring, also called spinning ring, on which a traveller is moveably arranged. The traveller guiding ring is arranged on a ring rail. The spindle and hence the cop is led through an opening in the ring rail. Usually the spinning positions on one machine side have a common ring rail.

[0008] For producing the yarn windings on the tube/spinning cop the yarn is threaded through the traveller which deflects the yarn provided from above laterally towards the cop.

[0009] For depositing the yarn windings along the longitudinal extension of the cop tube, the ring rail is moveable up and down during the spinning process. I.e. in order to build up yarn winding along the axis of the cop tube the ring rail is moved continuously up and down during the spinning process.

[0010] The ring spinning machine comprises a plurality of the above described spinning positions which are arranged next to each other along the longitudinal extension of the ring spinning machine. The ring spinning machine in particular form two machine sides which are facing in opposite directions. In particular, on both machine sides spinning positions are arranged next to each other as described above.

[0011] Usually, the spindles or at least a plurality of spindles of the ring spinning machine are driven by a common spindle drive. Thus, the spindles of a machine side or of a machine section can be driven by a common spindle drive. The drive power is transmitted to the spindles by driving belts which surround the spindle.

[0012] Once the spinning cops have reached their nominal volume or size during the spinning process, the spinning process is stopped and the spinning cops are lifted from the spindles and carried away. Empty tubes are put on the spindles and the spinning process is resumed.

[0013] The change of the spinning cops can be carried out manually or automatically. Usually, the change of the spinning cops, also called doffing, takes place during a common interruption of the spinning process for all cops on a machine side or even for all cops of the whole ring spinning machine.

[0014] The ring spinning device can comprise a doffing device for automatically changing the spinning cops, i.e. for automatically lifting the full spinning cops from the spindle and for putting on empty tubes on the spindles. The doffing device is arranged along the machine sides and operates in front of the spinning positions. In this case the doffing can take place simultaneously for all cops on a machine side or even for all cops of the ring spinning machine.

[0015] It is quite common that the ring spinning machine is equipped with an individual spinning position monitoring system, also called spindle monitoring system. The spinning position monitoring system in particular is designed for detecting yarn breakages.

[0016] The term "designed to/for" can also be read as "configured to/for".

[0017] More details on the spinning position monitoring system are disclosed further below in connection with the system.

[0018] Concerning the control of the spinning position monitoring system the control of the spinning position monitoring system can be integrated into the machine control of the ring spinning machine. However, the spinning position monitoring system can also be operated autonomously from the ring spinning machine, i.e. from its machine control.

[0019] In a ring spinning machine the yarns tends to break because of various reasons like low quality material, fast speed of machine, heat generated during the spinning, outside influences, such as draught, flying fibre material or other objects, and the like reasons.

[0020] The main job of the labourers involved in a spinning mill is to continuously monitor the spinning machine and check if there is an occurrence of a yarn breakage during the spinning process. The labourers may also be responsible for finding spindle defect occurrences that may include but not limited to a yarn breakages, slipping spindles, rogue spindles creating repetitive breaks, or any combination thereof. If the labourers find any such yarn breakage and/or said spindle defect occurrences, they have to promptly attend the yarn breakage and/or spindle defect occurrences to avoid unnecessary production losses.

[0021] However, as humans are involved, the process of monitoring is not effective and efficient as the human intervention involves substantial delay in detection of the above defects, and even if the defect is detected, attending such defects is a time consuming process. Further, if the defect occurs at multiple points in the machine, it is very difficult to attend the same by a single labourer/person. Hence, a plurality of labourers have to be hired and accordingly the production costs increase. Furthermore, the human interventions tend to be unreliable, ineffective and inefficient. Furthermore the working conditions at the spinning machines are not healthy due to high noise level, hot and humid environment and poor air quality.

[0022] For the reasons above it is aimed to automate as many service steps as possible and to reduce service personnel working at the spinning machines to a minimum.

[0023] It is therefore an object of present invention to provide a system and a method for automatic resurrection, i.e. restoration or rectifying of a yarn breakage in a ring spinning machine.

[0024] Basically, such systems are known in the state of the art. As fitting each spinning position with its own piecing device for rectifying yarn breakages would, however, be too expensive, such systems usually comprise a travelling piecing carriage which patrols along the spinning machine.

[0025] The piecing carriage has to perform mechanically the same rather complicated operations as the service personnel performs manually:

• watch for yarn breakages, in particular while patrolling the spindles, i.e. machine sides;
• stop at the corresponding spinning position when a yarn breakage is detected;
• take up an exact location relative to the spindle / spinning position;
• stop the spindle;
• search for and catch the broken yarn end on the cop;
• bring the traveller into a suitable position for threading up;
• thread the yarn through the traveller;
• thread the yarn through yarn guiding elements such as balloon control ring and lappet hook;
• piece the yarn with the fibre strand of the drafting arrangement and
• release the spindle, i.e. resume the spinning process.

[0026] The prior art discloses different approaches of resurrection of a yarn breakage.

[0027] DE 4010113 A1 discloses a system and method for automatically repairing broken yarn. To repair a broken yarn automatically, the document proposes that at a ring spinning machine an auxiliary yarn is drawn from a supply bobbin by a yarn carrier across the moving yarn sensor to a point below the ring rail. The ring traveller is then blown on to the auxiliary yarn and it is laid in coils round the cops and sleeve. The auxiliary yarn is then threaded into the ballooning limit ring and in the moving yarn sensor by rotating the spindle. The auxiliary yarn is then laid at the broken yarn end projecting at the outlet of the drafting arrangement, and the auxiliary yarn is severed from its bobbin.

[0028] JP-H-03199436 A discloses a system wherein a traveller is moved to a proper position by blowing air from a finger part and an auxiliary yarn is ejected together with air, wound around a wooden bobbin, passed through a traveller in corporation with the finger part and passed through a ballooning control ring and a lappet hook. The auxiliary yarn is cut with a cutter and is clamped with a gripper at a side of a delivery roller to feed a fibre strand and the auxiliary yarn in a superposed state. The auxiliary yarn is supplied by a feed apparatus containing a mechanism to cause slippage when an excessive tension is applied to the auxiliary yarn in the winding of the seed yarn on the wooden bobbin and the treading to the traveller.

[0029] US 3688486 A discloses a ring spinning frame including an apparatus for automatically doffing and donning bobbins and, if desired, for rejoining breaks occurring in a strand of yarn. A carriage passes the numerous spinning positions on the frame and automatically delays its travel to service any spinning position requiring attention.

[0030] EP 0421157 B1 discloses a ring spinning machine having means for spinning a yarn from a roving supplied by a fly frame and for winding said yarn onto a cop, further disclosing a travelling service carriage which carries an auxiliary bobbin with an auxiliary yarn, from which, in the event of rectification of a yarn break, a piece of yarn is applied to the cop and pieced to the roving. The service carriage is provided with means for monitoring the success of an attempt to rectify a yarn break. The means are connected to a control unit with controls means on the service carriage for removing from the cop a piece of auxiliary yarn used in a failed attempt, before a further attempt is made to rectify the yarn break.

[0031] US 3905187 A discloses a textile yarn piecing apparatus having a servicing assembly positionable in a first location for supplying a free end of auxiliary yarn from an auxiliary yarn bobbin to a revolving spindle having a bobbin onto which said free end is to be wrapped and with a surrounding ring having a traveller which is to be threaded onto said auxiliary yarn and positionable in a second location for piecing an intermediate portion of said auxiliary yarn to a roving issuing from roving delivery rolls and cutting the auxiliary yarn to again provide a cut free end thereof. The servicing assembly has a yarn feeding tube for conveying of yarn from the auxiliary yarn bobbin and an air suction yarn storage tube for storing a substantial length of the free end of the auxiliary yarn. The mouth openings of the yarn feeding and storage tubes are spaced from one another to provide a free yarn zone therebetween. There is also provided a yarn release air jet adjacent the free yarn zone, in the first location providing a release jet of air for removing the free end of yarn from the storage tube and propelling it toward the bobbin for wrapping therearound, the air suction yarn storage tube in the second location providing air suction for retrieving the cut free end of auxiliary yarn and storing it in the storage tube.

[0032] CN 102560770 B discloses a system for automatic detection of a yarn breakage and an apparatus and method for automatic piecing as well.

[0033] However, the above mentioned prior-art and the traditionally available approaches suffer from several drawbacks. For example: the automated device/apparatus/robot described in the above cited state of the art need to much time for achieving the above mentioned purpose. Accordingly, there still exists scope of improvement in the automated process. Furthermore, some mechanical work steps shown in the state of art are either too complicated or have shown as not functioning reliably.

[0034] It is therefore an object of present invention to provide a moveable yarn breakage handling device for automated resurrection of a yarn breakage and accordingly for automated piecing of broken yarns in a ring spinning machine.

[0035] Another object of the present invention is to eliminate a human operation or human intervention for attending yarn breakages by means of a moveable yarn breakage handling device.

[0036] Another object of the present invention is to provide an automated system containing a moveable yarn breakage handling device for automated resurrection of a yarn breakage and an individual spinning position monitoring system, which allows to automatically attend yarn breakages on spinning positions of a ring spinning machine which have been detected by the individual spinning position monitoring system.

[0037] Another object of the present invention is to provide an automated system containing a moveable yarn breakage handling device for automated resurrection of a yarn breakage and an individual spinning position monitoring system, wherein based on a yarn breakage and/or a spindle defect occurrence the moveable yarn breakage handling device is capable of replenishing an empty or partly processed roving bobbin from the supply area in the ring spinning machine with a new full roving bobbin for producing yarn and of attending the yarn breakage and or spindle defect.

[0038] Another object of present invention is to provide a device, a system and a method for attending other spindle defect occurrences in order to ensure quicker restoration of the yarn spinning process on the affected spinning position of the ring spinning machine and also to eliminate the production of inferior yarns due to a spindle defect.

[0039] The device, system and method shall decrease production losses and increase effectiveness and efficiency of the yarn production process.

[0040] Another object is to provide an automated robot device to achieve the task of automatic monitoring of the overall spinning machines to automatically detect the above defects and automatically attend the defects and continue the ring spinning machine without any manual intervention thereby achieving effective, efficient and productive process with overall decrease in time of normal spinning process.

[0041] At least one of the objective is solved by the features of independent claims 1, 13 and 14. Specific embodiments of the invention and further developments of the invention are subject of the dependent claims, the description and the drawings.

[0042] According to the invention the yarn breakage handling device for automated resurrection, i.e. rectifying, of a yarn breakage in a ring spinning machine comprises a robot arrangement for carrying out a plurality of work steps for resurrection of a yarn breakage and a transportation arrangement with a drive for transporting the device along the ring spinning machine.

[0043] The term "arrangement" has to be understood as a functional unit in the first instance. In second place the term "arrangement" can also mean a physical unit.

[0044] The term "comprise" when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

[0045] The yarn breakage handling device in particular is a moveable carriage, in particular a service carriage.

[0046] The robot arrangement comprises:

• a yarn capturing unit having a yarn attracting and picking mechanism for attracting and retrieving, i.e. picking the yarn end from the cop and a moving and positioning mechanism for moving and positioning the yarn attracting and picking mechanism, and
• a yarn threading unit for threading the yarn into the traveller, having a yarn holding mechanism, a traveller positioning mechanism and a moving and positioning mechanism for moving and positioning the yarn holding mechanism and the traveller positioning mechanism.

[0047] In particular, the robot arrangement also comprises a spindle stopper unit for stopping the rotation of the spindle during resurrection of the yarn breakage.

[0048] The term "unit" has to be understood as a functional unit in the first instance. In second place the term "unit" can also mean a physical unit.

[0049] In particular, the yarn breakage handling device comprises a computer appliance for operating the robot arrangement, in particular its functional units as mentioned above.

[0050] In particular, the computer appliance serves for operating the transportation arrangement, in particular its drive.

[0051] The term "appliance" has to be understood as a functional unit in the first instance. In second place the term "appliance" can also mean a physical unit.

[0052] The computer appliance in particular comprises at least one control unit for controlling the robot arrangement, i.e. its functional units.

[0053] The computer appliance in particular comprises at least one control unit for controlling the transportation arrangement, in particular its drive. In other words the at least one control unit serves for controlling the movement of the yarn breakage handling device. In particular, the computer appliance comprises at least one evaluation unit for evaluating sensor data from sensors arranged on the yarn breakage handling device.

[0054] The yarn breakage handling device can comprises a malfunction localisation sensor, which localises spinning positions with a malfunction or failure in the yarn production. In particular, the malfunction localisation sensor is a yarn breakage localisation sensor. Such a sensor in particular is provided if the yarn breakage handling device is partly or fully autonomous operable, i.e. if the yarn breakage handling device does not receive the spinning position data of a malfunction, i.e. yarn breakage, from an external device, such as a spinning position monitoring system.

[0055] The malfunction localisation sensor can be an optical sensor. The malfunction localisation sensor in particular is a camera.

[0056] In an embodiment the malfunction localisation sensor is in particular designed for detecting a light signal. The light signal is emitted on the affected spinning position for indicating a malfunction of the yarn production, such as a yarn breakage. The light signal can e.g. be generated and emitted by the spinning position monitoring system for indicating a yarn breakage.

[0057] The light signal indicating a yarn breakage can be the light up itself or a specific colour of the light, such as a red light, intensity of the light, or a flashing of the light.

[0058] The malfunction localisation sensor can be configured to detect different light signals which stand for different kind of malfunction, such as yarn breakage, slipping spindles, rogue spindles, etc.

[0059] The different light signals can be characterised by different light colours. The different light signals can also be characterised by different light behaviour, such as light intensity, light duration, i.e. flashing interval (permanent, blinking, etc.).

[0060] The control unit of the computer arrangement of the spinning monitoring system or of the computer appliance of the yarn breakage handling device can decide dependent on the kind of malfunction indicated by the light signal whether the malfunction, in particular a yarn breakage, is to be dealt with or not.

[0061] In another embodiment the malfunction localisation sensor is configured to detect the presence of a yarn. The malfunction localisation sensor can be configured to detect whether a yarn is running between the delivery rollers of the drafting arrangement and the cop or not. In particular, the malfunction localisation sensor detects if no yarn is running and wound up onto a cop and sends a signal e.g. to the control unit of the yarn breakage handling device, which causes the yarn breakage handling device to move towards that spinning position to attend the yarn break.

[0062] In another embodiment the malfunction localisation sensor is configured to detect the movement of the traveller. The malfunction localisation sensor can be configured to detect whether the traveller is moving or not. In particular, the malfunction localisation sensor detects if the traveller is not moving, i.e. is at a standstill, and sends a signal e.g. to the control unit of the yarn breakage handling device, which causes the yarn breakage handling device to move towards that spinning position to attend the yarn break.

[0063] In a further development the malfunction localisation sensor is configured to detect different movement speeds of the traveller as well. This enables to detect e.g. a slipping spindle which is characterised by a lower movement speed of the traveller in comparison the movement speed of the traveller in regular yarn production process. In both latter embodiments an individual spinning position monitoring system is not needed.

[0064] In an embodiment the yarn breakage handling device contains at least two malfunction localisation sensor, wherein a first sensor is positioned for detecting yarn breakages on a machine side of a first ring spinning machine and a second sensor is positioned for detecting yarn breakages on a opposing machine side of a second ring spinning machine. This allows the detection of yarn breakages on both machine sides while the yarn breakage handling device is patrolling along the corridor between two ring spinning machines.

[0065] The yarn capturing unit can comprise at least one robot arm, in particular an articulated robot arm. In this embodiment the yarn attracting and picking mechanism is arranged on a robot arm, in particular in a distal end of the robot arm.

[0066] In particular, the moving and positioning mechanism is configured for actuating the corresponding robot arm.

[0067] The yarn capturing unit can comprise a yarn holding mechanism, in particular clamping mechanism, for holding, in particular clamping, the picked yarn.

[0068] In particular, the yarn holding mechanism for holding the picked yarn is arranged on a robot arm, in particular in a distal end of the robot arm.

[0069] In particular, the yarn attracting and picking mechanism and the yarn holding mechanism are arranged on a common robot arm.

[0070] In particular, the yarn attracting and picking mechanism and the yarn holding mechanism can be located in a combined module.

[0071] The term "module" in particular means a mechanical unit.

[0072] The yarn capturing unit can comprise a yarn separating mechanism, in particular a yarn cutting mechanism, for separating, i.e. cutting, an excess end length, i.e. an yarn overlength of the picked yarn.

[0073] In particular, the yarn separating mechanism is arranged on a robot arm, in particular in a distal end of the robot arm.

[0074] In particular, the yarn attracting and picking mechanism and the yarn separating mechanism are arranged on a common robot arm.

[0075] In particular, the yarn holding mechanism and the yarn separating mechanism are arranged on a common robot arm.

[0076] In particular, the yarn attracting and picking mechanism, the yarn holding means and the yarn separating mechanism are arranged on a common robot arm.

[0077] In particular, the yarn attracting and picking mechanism and the yarn separating mechanism can be located in a combined module.

[0078] In particular, the yarn holding mechanism and the yarn separating mechanism can be located in a combined module.

[0079] In particular, the yarn attracting and picking mechanism, the yarn holding mechanism and the yarn separating mechanism can be located in a combined module.

[0080] In an embodiment of the invention the yarn capturing unit is designed for permanently holding, i.e. clamping, the yarn starting from picking the yarn end from the cop until piecing the yarn to the fibre strand of the drafting arrangement.

[0081] I.e., the yarn capturing unit in particular is configured to keep holding, i.e. clamping, the yarn during the threading of the yarn into the traveller by means of the yarn threading unit as described further below in connection with the method.

[0082] In an embodiment of the invention the yarn attracting and picking mechanism comprises a yarn suction tube for sucking in the yarn end from the surface of the cop. The yarn suction tube in particular has a front opening on which air is sucked in. Accordingly, the yarn end is sucked in at the front opening.

[0083] The yarn suction tube forms a receiving space, in particular a closed channel or passage for the captured yarn end. The receiving space in cross-sectional view can be round shaped, in particular circular.

[0084] In particular, the yarn suction tube is open on both sides such that a yarn end which is sucked in at a first tube opening, which is a front opening viewed in direction of the suction position, passes through the yarn suction tube and leaves the yarn suction tube through a second tube opening, which is a rear opening viewed in direction of the suction position.

[0085] In an embodiment the yarn suction tube comprises at least one air inlet for feeding/injecting air, in particular pressurised air, into the interior of the yarn suction tube.

[0086] The at least one air inlet, that is to say air inlet channel, in particular is configured such that the injected air has an inflow component which runs parallel to the tube axis in direction of the rear opening.

[0087] The at least one air inlet can be configured such that the injected air has an inflow component which runs towards the centre of the passage of the suction tube.

[0088] The at least one air inlet can be configured such that the injected air has an inflow component which runs tangentially to the passage in cross-sectional view.

[0089] The yarn suction tube in particular comprises a plurality of air inlets which are arranged on the inner circumference of the yarn suction tube. The plurality of air inlets in particular are arranged around the inner circumference. The plurality of air inlets in particular are arranged concentrically around the inner circumference.

[0090] The at least one airs inlet can be configured such that a vortex air flow is produced which is directed to the rear opening of the yarn suction tube.

[0091] Due to the air flow component directed to the rear opening the injected air flows towards the rear end of the suction tube and leaves the suction tube through the rear end. Accordingly, a suction, i.e. a suction draught is generated at the front opening of the suction tube which is capable of attracting the yarn end from the spinning cop.

[0092] It has been figured out that when processing fine yarn counts yarn end detaching means may be necessary additionally in order to loosen, i.e. separate or detach the yarn end from the surface of the cop in a first step before the suction draught being capable of attracting and sucking in the yarn end.

[0093] The reason may be found in the hairiness of the yarn which is an intrinsic feature of most yarns. Due to the hairiness the yarn end sticks together with neighbouring windings which makes it difficult to separate the yarn end from the cop by suction only.

[0094] The yarn end detaching means can be a mechanical configuration which mechanically acts on the cop surface and thus on the yarn windings on the cop surface in order to loosen. i. e. detach the free end of the yarn from the cop surface. The mechanical configuration can be a brush, bristles or a lamella by means of which the yarn end can be mechanically separated, i.e. detached from the cop, i.e. brushed off the cop.

[0095] The yarn end detaching means can also be a pneumatic configuration for producing an air output, that is to say air discharge, in particular air blasts or blowing air, which act on the cop surface and thus on the yarn windings on the cop surface in order to loosen, i.e. detach the free end of the yarn from the cop surface. Accordingly, the air output in particular is directed towards the surface of the cop. In other words air is blown towards the surface of the cop.

[0096] In particular, the pneumatic configuration contains at least one outlet opening through which air can be discharged.

[0097] The yarn end detaching means can be arranged on the yarn capturing unit. The yarn end detaching means can be arranged on a common robot arm together with the yarn attracting and picking mechanism.

[0098] The yarn end detaching means can be arranged on the yarn attracting and picking mechanism.

[0099] In case of a mechanical yarn end detaching configuration it can be arranged at the front opening of the suction tube.

[0100] The yarn end detaching means can also be arranged on a separate, that is to say on an own robot arm, in particular on an articulated robot arm. Thus, the yarn end detaching means can be part of a (separate) yarn end detaching unit.

[0101] The yarn end detaching means in particular are arranged in a distal end of the robot arm. Such a yarn end detaching unit can further comprise a moving and positioning mechanism for moving and positioning the yarn end detaching means. In particular, the moving and positioning mechanism is configured for actuating the corresponding robot arm.

[0102] The yarn end detaching unit and thus the yarn end detaching means in particular are moveable independently from the yarn capturing unit and thus from the yarn attracting and picking mechanism.

[0103] Accordingly, in a first step the yarn end detaching means in particular can be moved up and down along the cop axis - analogous to the suction step as described further below - while the cop is rotated, in particular slowly rotated, by the cop lifter unit.

[0104] The mechanical configuration or in case of a pneumatic configuration the air discharge, that is to say air blasts, detach the yarn end from the cop surface.

[0105] In a second step the yarn attracting and picking mechanism tries to catch the detached, i.e. loosened yarn end e.g. by means of suction applied to the cops surface by the suction tube as described further below in more detail.

[0106] In case of a pneumatic configuration, said pneumatic configuration can also be integrated into the yarn attracting and picking mechanism. Thus, the yarn attracting and picking mechanism can be configured to produce an air output, such as air blasts, which are directed towards the cop surface.

[0107] The air output can occur through the suction tube. In particular, air can be discharged through the front opening of the yarn suction tube. Latter suction tube is then rather generally a pneumatic tube for applying alternatingly air discharge and suction. The yarn attracting and picking means in particular are configured for switching between suction and air output, i.e. discharge.

[0108] Accordingly, the suction tube, that is to say the pneumatic tube is part of the above mentioned pneumatic configuration. Hence, the suction tube can contain at least one air inlet for discharging, i.e. feed air into the channel, i.e. passage of the suction tube having an air flow component directed to the front opening. This way an air output, i.e. discharge is produced at the front opening.

[0109] By means of switching the air discharge, i.e. feed into the suction tube between different air inlets an air current can be produced within the suction tube having an air flow component directed to the front opening, and thus air is ejected/discharged at the front opening for loosening the yarn end from the surface of the cop or an air current can be produced having an air flow component directed to the rear opening and thus air is sucked in at the front opening for picking the yarn end.

[0110] The above mentioned yarn holding mechanism in particular is arranged at the rear end or in the rear end section of the yarn suction tube.

[0111] The yarn holding mechanism can be integrated into the suction tube. The yarn holding mechanism together with the yarn attracting and picking mechanism, in particular the yarn suction tube, can form a combined module.

[0112] The yarn holding mechanism can be a separate module arranged at the rear end of the suction tube, forming an extended channel, i.e. passage for the yarn.

[0113] The yarn holding mechanism - designed as clamping mechanism - can comprise a clamping element which is moveable transverse to the channel, i.e. passage, in particular transverse to the longitudinal axis of the yarn suction tube. The clamping element can cooperate with a counterpart, i.e. a die, arranged on the opposite side of the channel, i.e. passage.

[0114] Accordingly, the clamping element can be configured for traversing, i.e. crossing the channel, i.e. passage, of the yarn suction tube.

[0115] Thus, the yarn can be clamped between the clamping element and the counterpart by moving the clamping element transversely through the channel, i.e. passage, and thus taking along the yarn which comes to rest at the counterpart.

[0116] As mentioned above, the yarn capturing unit can comprise a yarn separating mechanism, in particular a yarn cutting mechanism for separating, i.e. cutting, a yarn overlength, i.e. excess length, which e.g. is hanging out of the rear end of the channel, i.e. passage.

[0117] Accordingly, the yarn separating mechanism in particular is arranged at the rear end or in the rear end section of the yarn suction tube.

[0118] The yarn separating mechanism can be integrated into the suction tube. The yarn separating mechanism together with the yarn attracting and picking mechanism, in particular the yarn suction tube, can form a combined module.

[0119] The yarn separating mechanism can be a separate module arranged at the rear end of the suction tube, forming an extended channel, i.e. passage for the yarn.

[0120] The yarn separating mechanism together with the yarn holding mechanism can form a combined module arranged at the rear end of the suction tube, forming an extended channel, i.e. passage for the yarn.

[0121] The yarn separating mechanism and the yarn holding mechanism together with the yarn attracting and picking mechanism, in particular the yarn suction tube, can form a combined module.

[0122] In particular, the yarn separating mechanism, i.e. at least its separating point, is arranged following the yarn holding mechanism, i.e. at least its holding point, in process direction, i.e. as viewed from the front opening of the yarn suction tube in direction of the rear end of the yarn suction tube.

[0123] The yarn separating mechanism - designed as cutting mechanism - can comprise a cutting element, such as a knife or a blade, which is moveable transverse to the channel, i.e. passage, in particular transverse to the longitudinal axis of the yarn suction tube. The yarn cutting knife can cooperate with a counterpart, i.e. die, arranged on the opposite side of the channel, i.e. passage.

[0124] Accordingly, the cutting element can be configured for traversing, i.e. crossing the channel, i.e. passage, of the yarn suction tube.

[0125] The cutting element can be configured for traversing the channel of the yarn suction tube or a channel, i.e. passage following the yarn suction tube.

[0126] Thus, the yarn can be cut between the cutting element and the counterpart by moving the cutting element transversely through the channel, i.e. passage, and thus taking along the yarn which comes to rest at the counterpart and is cut.

[0127] In particular, the yarn separating mechanism is arranged on a robot arm.

[0128] In particular, the yarn attracting and picking mechanism and the yarn separating mechanism are arranged on a common robot arm.

[0129] In particular, the yarn attracting and picking mechanism, the yarn holding mechanism and the yarn separating mechanism are arranged on a common robot arm.

[0130] The yarn capturing unit can contain a yarn detection sensor for detecting the presence of a yarn in the channel, i.e. passage. In particular, the yarn detection sensor is arranged following the yarn holding mechanism as viewed from the front opening of the yarn suction tube in direction of the rear end of the yarn suction tube. In particular, the yarn detection sensor is arranged following the yarn separating mechanism in the sense above.

[0131] The yarn detection sensor can be an optical sensor, e.g. a camera.

[0132] In particular, the yarn detection sensor is arranged on a robot arm.

[0133] In particular, the yarn holding mechanism and the yarn detection sensor are arranged on a common robot arm.

[0134] In particular, the yarn attracting and picking mechanism and the yarn detection sensor are arranged on a common robot arm.

[0135] In particular, the yarn detection sensor, the yarn attracting and picking mechanism and the yarn holding mechanism are arranged on a common robot arm.

[0136] In particular, the yarn detection sensor, the yarn attracting and picking mechanism, the yarn holding mechanism and the yarn separating mechanism are arranged on a common robot arm.

[0137] In particular, the yarn detection sensor together with the yarn attracting and picking mechanism, in particular with the yarn suction tube, forms a combined module.

[0138] In particular, the yarn detection sensor together with the yarn holding mechanism forms a combined module, which in particular is arranged at the rear end of the yarn suction tube.

[0139] In particular, the yarn holding mechanism, the yarn separating mechanism and the yarn detection sensor form a combined module, which in particular is arranged at the rear end of the yarn suction tube.

[0140] In particular, the yarn detection sensor together with the yarn holding mechanism and the yarn attracting and picking mechanism, in particular the yarn suction tube, forms a combined module.

[0141] In particular, the yarn detection sensor together with the yarn separating mechanism, the yarn holding mechanism and the yarn attracting and picking mechanism, in particular the yarn suction tube, forms a combined module.

[0142] The yarn threading unit can comprise at least one robot arm, in particular an articulated robot arm. In this embodiment the yarn holding mechanism is arranged on a robot arm, in particular in a distal end of the robot arm.

[0143] In particular, the traveller positioning mechanism is arranged on a robot arm, in particular in a distal end of the robot arm.

[0144] In particular, the yarn holding mechanism and the traveller positioning mechanism are arranged on a common robot arm.

[0145] In particular, the yarn holding mechanism and the traveller positioning mechanism form a combined module.

[0146] In particular, the corresponding moving and positioning mechanism is configured for actuating the robot arm.

[0147] In an embodiment of present invention the yarn holding mechanism of the yarn threading unit comprises at least two holding fingers, which at least in operational position define a span for spanning a yarn section, i.e. a stretch of yarn, between the at least two holding fingers, as described further below.

[0148] The holding fingers are designed for holding a yarn. In particular, each holding finger has a moveable securing element for securing the yarn on the holding finger.

[0149] The yarn holding fingers in each case can form a receiving recess for receiving the yarn, in particular for receiving the yarn on the front side of the yarn holding fingers. The receiving recess in particular is arranged in a free end section of the yarn holding finger. The receiving recess in particular is arranged at the free front end of the yarn holding finger with a recess opening directed to the front end of the yarn holding finger.

[0150] In particular, the mentioned securing element is moveable transverse to the longitudinal axis of the holding finger.

[0151] In particular, the mentioned securing element is moveable transverse to the axis connecting the recesses of the two yarn holding fingers.

[0152] In particular, the securing element is moveable transverse to the receiving recess and capable of taking along, i.e. entrain and deflect, the yarn arranged in the recess.

[0153] In particular, each yarn holding finger contains an entrainment groove or deepening for accommodating and thus guiding the deflected yarn. The guiding groove begins at the receiving recess and run transverse to the longitudinal axis of the yarn holding finger and transverse to axis connecting the receiving recesses of the two yarn holding fingers.

[0154] In particular, the traveller positioning mechanism is configured for positioning the traveller in the front, i.e. on the front side of the traveller guiding ring, i.e. of the ring rail.

[0155] In particular, the traveller positioning mechanism comprises active means which act on the traveller.

[0156] In particular, the traveller positioning mechanism comprises pneumatic means for producing air currents which act on the traveller.

[0157] The air current can be air blows or blasts. In other words, the pneumatic means can be configured for discharging air.

[0158] The air current can be a suction draught. In other words, the pneumatic means can be configured for sucking in air.

[0159] It is also possible that the pneumatic means are configured for switching between air discharge and sucking in air.

[0160] It is also possible that the traveller positioning mechanism comprises magnetic means, such as magnet strips, which act on the traveller. The magnetic means can comprise permanent magnets or non-permanent electro-magnets.

[0161] In an embodiment the traveller positioning mechanism comprises at least two traveller positioning members, in particular traveller positioning fingers, for positioning the traveller. The at least two traveller positioning members are distanced to each other in an operational mode, such that a first positioning member can be positioned to the right and a second positioning member can be positioned to the left of the spinning cop. The traveller positioning members can be arranged on the yarn holding fingers. I.e., on each yarn holding finger a traveller positioning member is arranged, e.g. mounted. In particular, the alignment of the traveller positioning member is parallel to the holding finger. In particular, the traveller positioning member extends beyond the yarn holding finger.

[0162] The traveller positioning members include the active means, as mentioned above, which act on the traveller for positioning.

[0163] In a further development of the invention each positioning member has at least one passage opening for the passage of air in order to produce an air current acting on the traveller. Through the at least passage opening air can be discharged, e.g. air blows or air blasts. Through the at least one passage opening air can be sucked in. The positioning member in each case can comprise separate openings or a common opening for discharging air and sucking in air.

[0164] The produced air current is able to act on the traveller for moving and thus positioning the traveller on the traveller guiding ring.

[0165] In a further development, the robot arrangement comprises a level verifying unit for lifting and lowering at least the yarn threading unit synchronously with the movement of the ring rail of the ring spinning machine.

[0166] In particular, the level verifying unit is configured for lifting and lowering the yarn capturing unit synchronously with the movement of the ring rail of the ring spinning machine.

[0167] In particular, the level verifying unit comprises a ring rail sensor for detecting the movement of the ring rail. The ring rail sensor can be a position sensor for measuring the distance between the sensor, i.e. the sensor receiver, and the ring rail or a distance change between the sensor, i.e. the sensor receiver, and the ring rail. I.e. the ring rail sensor can either measure an absolute position of the ring rail or a relative one (displacement). The ring rail sensor in particular is an optical sensor. The measuring path of the ring rail sensor is in particular directed from above, in particular from vertical above, onto the ring rail.

[0168] The level verifying unit in particular is configured for lifting and lowering the yarn threading unit that is to say the yarn holding and traveller positioning mechanism, and - as the case may be - the yarn capturing unit, synchronously with the movement of the ring rail of the ring spinning machine based on the measurements, i.e. the sensor data, of the ring rail sensor.

[0169] The level verifying unit in particular contains a carrier and a lifting and lowering mechanism which is configured for lifting and lowering the carrier. The level verifying unit is configured for lifting and lowering the carrier synchronously with the movement of the ring rail of the ring spinning machine based on the measurements of the ring rail sensor.

[0170] The lifting and lowering mechanism can be driven pneumatically, hydraulically or electrically. Accordingly, the lifting and lowering mechanism can comprise at least one hydraulic cylinder (hydraulic driven) or at least one pneumatic cylinder (pneumatically driven) or at least one electric motor, in particular a step motor (electrically driven).

[0171] The yarn threading unit, that is to say the yarn holding and traveller positioning mechanism, and - as the case may be - the yarn capturing unit, are now arranged, e.g. mounted, on the mentioned carrier, e.g. via their robot arms.

[0172] However, it can also be envisaged that the sensor data of the ring rail sensor are directly fed into a computer appliance for evaluating the sensor data and for controlling the movement of the yarn threading unit, e.g. its robot arm, based on the sensor data. Accordingly, the changing height level of the ring rail is directly considered, i.e. implemented in the movement of yarn threading unit, e.g. its robot arm, and accordingly of the yarn holding and traveller positioning mechanism of the yarn threading unit.

[0173] As mentioned, the robot arrangement in particular comprises a spindle stopper unit for stopping the rotation of the spindle during resurrection of the yarn breakage.

[0174] The spindle stopper unit can comprise at least one a robot arm.

[0175] The spindle stopper unit in particular comprise a spindle stopper element. The spindle stopper element can be arranged on a robot arm, in particular in a distal end of the robot arm.

[0176] In particular, the moving and positioning mechanism is configured for actuating the robot arm.

[0177] In particular, the spindle stopper unit is designed to make/establish a frictional contact with the spindle, which brings the spindle to a stop. Hereto the spindle stopper element can directly establish such a frictional contact.

[0178] However the spindle stopper element can also activate an existing spindle brake which e.g. establish said frictional contact.

[0179] In a further development of the invention the robot arrangement comprises a cop lifter unit for lifting the spinning cop from the spindle.

[0180] The cop lifter unit can comprise a grasping mechanism for grasping or gripping the spinning cop, in particular the tube of the spinning cop.

[0181] The cop lifter unit can comprise a moving and positioning mechanism for moving and positioning the grasping mechanism.

[0182] In particular, the moving and positioning mechanism is configured for lifting the spinning cop from the spindle and for lowering the spinning cop onto the spindle.

[0183] In an embodiment the grasping mechanism comprises an insertion tool, which can be inserted into the interior of the tube of the spinning cop.

[0184] The insertion tool can comprise an expansion member which is configured for being expanded within the tube and thus creating a frictional connection and/or a form fit between the insertion tool and the tube of the spinning cop.

[0185] The expansion member can be configured for being hydraulically or pneumatically expandable.

[0186] The expansion member can be an expandable cuff which is arranged on the insertion tool.

[0187] The expansion member can comprise an expansion chamber. The expansion chamber can be filled with a fluid or a gas, such as air, for expansion. The expansion chamber in particular can be filled with pressurised air for expansion.

[0188] The expansion member can be of a flexible, in particular elastic material or comprise this. The expansion member can be of plastic, such as elastomer, or comprise this.

[0189] In order to release the cop, the expansion of the expansion member only has to be abolished. This way the friction connection and/or form fit is released.

[0190] The cop lifter unit can comprise a rotation mechanism for rotating the grasped spinning cop. In particular, the rotation mechanism is configured for rotating the grasping mechanism, and in particular its insertion tool.

[0191] The cop lifter unit can comprise a robot arm, in particular an articulated robot arm. In this embodiment the cop grasping mechanism is arranged on the robot arm, in particular in a distal end of the robot arm.

[0192] In particular, the corresponding moving and positioning mechanism is configured for actuating the robot arm.

[0193] The robot arrangement can comprises a lappet hook lifter unit for lifting the lappet hook. The lappet hook lifter unit comprises in particular a lappet hook lifter.

[0194] The lappet hook lifter unit can comprise a moving and positioning mechanism for moving and positioning the lappet hook lifter.

[0195] The lappet hook lifter unit can comprise a robot arm, in particular an articulated robot arm. In this embodiment the lappet hook lifter is arranged on the robot arm, in particular in a distal end of the robot arm.

[0196] In particular, the corresponding moving and positioning mechanism is configured for actuating the robot arm.

[0197] In a further development of the invention the yarn breakage handling device, i.e. its robot arrangement, comprises a roving motion activating unit with an activating mechanism for operating a roving stop motion device as it is e.g. known from the state of the art. The roving motion activating unit is configured to operate a roving stop motion device for resuming the supply of input roving material to the drafting arrangement of the ring spinning machine.

[0198] In particular, the roving motion activating unit comprises a moving and positioning mechanism for moving and positioning the activating mechanism.

[0199] In particular, the roving motion activating unit is configured to switch ON the roving stop motion device thereby resuming the supply of input roving material automatically to the drafting arrangement. After resumption of supply of roving, the yarn breakage handling device can start its piecing operation as described further below in more details.

[0200] The roving motion activating unit can comprise at least one robot arm, in particular an articulated robot arm. The activating mechanism is arranged on a robot arm, in particular in a distal end of the robot arm.

[0201] In particular, the moving and positioning mechanism is configured for actuating the corresponding robot arm.

[0202] In an embodiment, the roving motion activating unit, respectively its activating mechanism can be arranged on a common robot arm together with one of:

• lappet hook lifter unit;
• cop lifter unit;
• yarn capturing unit or
• yarn piecing unit.

[0203] The activating mechanism can also be integrated into the lappet hook lifter of the lappet hook lifter unit.

[0204] The activating mechanism can also be integrated into the grasping mechanism of the cop lifter unit.

[0205] The activating mechanism can also be integrated into the yarn attracting and picking mechanism of the yarn capturing unit.

[0206] The activating mechanism can also be integrated into the piecing mechanism of the yarn piecing unit.

[0207] The forementioned transportation arrangement is designed for carrying and moving the yarn breakage handling device, i.e. the robot arrangement. In particular, the transportation arrangement is designed for carrying the yarn breakage handling device, i.e. the robot arrangement at least along a row of spinning positions of a ring spinning machine, and most particular at least along the entire longitudinal axis of the ring spinning machine for attending yarn breakages and as the case may be other spindle defects.

[0208] The transportation arrangement in particular contains at least one roller, in particular a plurality of rollers, which may be driven by the drive. In particular, the rollers are wheels.

[0209] The transportation arrangement and thus the yarn breakage handling device is in particular floor bound, i.e. ground bound.

[0210] The transportation arrangement can be railbound. Hereto the transportation arrangement comprises rail guided running rollers. The rails can be floor rails. The rails can also be suspended, i.e. they can be arranged overhead (overhead rails). However, the yarn breakage handling device is preferably not railbound, i.e. freely movable on the floor, i.e. ground.

[0211] In an embodiment the yarn breakage handling device can be designed as partly or fully autonomously operable.

[0212] For example, the yarn breakage handling device can be moveable without commands or control data from outside the yarn breakage handling device. In particular, the yarn breakage handling device can be moveable without navigation data from outside the yarn breakage handling device.

[0213] The yarn breakage handling device, i.e. the robot arrangement is operable and can attend to yarn breakages without commands or control data from outside the yarn breakage handling device.

[0214] A partly autonomously operable yarn breakage handling device can for example receive navigation data from an external computer appliance or from an active or a passive component outside the yarn breakage handling device.

[0215] The navigation data can e.g. be spatial reference data, such as spatial reference points, for creating an own navigation map.

[0216] A spatial reference point can e.g. be represented by an RFID-tag, or another information tag which is detectable or readable by a sensor or receiver of the yarn breakage handling devices. The RFID-tag, or another information tag can e.g. be arranged at the ring spinning machine or at the floor.

[0217] A partly autonomously operable yarn breakage handling device can for example receive spinning position data from an external computer appliance concerning yarn breakages.

[0218] However, also the fully autonomously operable yarn breakage handling device is in particular designed for receiving data from own sensors which are designed for detecting a yarn breakage or for navigating the yarn breakage handling device. Navigating e.g. means the secure movement of the device along the spinning machine and positions, as well as the aligning of the device in front of an affected spinning position.

[0219] As mentioned, the yarn breakage handling device in particular comprises a computer appliance for navigating the yarn breakage handling device.

[0220] The operation of the robot arrangement and the navigation of the yarn breakage handling device can be carried out by a common computer appliance.

[0221] The control of the robot arrangement and the control of the transportation arrangement can be carried out by a common control unit.

[0222] As mentioned the yarn breakage handling device can be partly or fully autonomous navigable. In this case the yarn breakage handling device can be navigable by means of and internal navigation system, which in particular is not dependable on external navigation data. Such a navigation system can e.g. be based on SLAM (Simultaneous Localization and Mapping) technology.

[0223] In robotics SLAM technology is applied for mapping and navigation, i.e. constructing or updating of a map of an unknown environment while simultaneously keeping track of the position and orientation of the robot within it.

[0224] The yarn breakage handling device can comprise at least one sensor, in particular a plurality of sensors for providing information for mapping and navigating the yarn breakage handling device. The at least one sensor can be a position sensor. The at least one sensor can be an optical sensor, such as a laser sensor (laser rangefinder). The at least one sensor can be a camera.

[0225] The at least one sensor, in particular camera, can be part of a navigation sensor system on the yarn breakage handling device for navigation, in particular detailed navigation of the yarn breakage handling device. The at least one sensor mentioned above in particular is configured for providing navigation information.

[0226] It is possible, that at least one sensor, e.g. an optical sensor, in particular a camera, serves for detecting yarn breakages as well as for providing navigation information to the yarn breakage handling device.

[0227] In an embodiment of the invention the yarn breakage handling device comprises at least two sensors, in particular optical sensors, preferably cameras.

[0228] The two sensors in each case can be configured for detecting yarn breakages along a machine side of a ring spinning machine.

[0229] The two sensors, in this case as part of the navigation sensor system, in each case can be configured for providing navigation information.

[0230] I.e. a first sensor can be configured for detecting yarn breakages along a left machine side of a first ring spinning machine and the second sensor can be configured for detecting yarn breakages along a right machine side of a second ring spinning machine, while the yarn breakage handling device is moved along a service lane between two ring spinning machines.

[0231] Further, the first sensor can be configured for collecting navigation information from the region of the left machine side of a first ring spinning machine and the second sensor can be configured for collecting navigation information from the region of the right machine side of the second ring spinning machine, while the yarn breakage handling device is moved along a service lane between two ring spinning machines.

[0232] The sensors can be configured for detecting a light signal emitted by a spinning position monitoring system indicating a yarn breakage.

[0233] Accordingly, the measuring paths of the two sensors can have measuring path components which run in opposite directions and which in particular run perpendicular to the longitudinal direction of the spinning machine.

[0234] It is however possible, that the measuring paths of the two sensors have a measuring path component which run parallel to each other and which in particular run parallel to the longitudinal direction of the spinning machine.

[0235] The above mentioned two sensors can also be configured for collecting information /data for navigating, in particular for mapping and navigating.

[0236] In order to reliably carrying out the resurrection of the yarn breakage the yarn breakage handling device does not only has to be moved in front of the affected spinning position but preferably also has to be precisely positioned, i.e. aligned in front of the spinning position and relative to this. The positioning, i.e. alignment in particular happens based on at least one point of reference on the spinning position.

[0237] The said positioning, i.e. alignment in particular comprises a lateral alignment.

[0238] The said positioning, i.e. alignment in particular comprises a distance setting, i.e. an alignment in distance.

[0239] The precise positioning of the yarn breakage handling device allows to determine absolute distances to the components of the spinning position which facilitates the control of the robot arrangement.

[0240] The yarn breakage handling device in particular comprises at least one positioning sensor for sensing at least reference point on the spinning position.

[0241] According to an embodiment of present invention such a reference point is the light signal emitted by the spinning position monitoring system.

[0242] Accordingly, the yarn breakage handling device can contain a positioning sensor, in particular an optical positioning sensor, such as a camera, for detecting said light signal. The yarn breakage handling device is configured for sensing the light signal and for laterally positioning the yarn breakage handling device such that the measuring path of the sensor is directed to the centre of the light signal (source).

[0243] Accordingly, said sensor in particular is part of a navigation sensor system.

[0244] The measuring path of the positioning sensor in particular runs perpendicular to the ring rail, i.e. to the longitudinal extension of the ring spinning machine and in particular horizontal.

[0245] Once the measuring path of the sensor is directed to the centre of the light signal (source) the final lateral position of the yarn breakage handling device relative to the spinning position is determined, i.e. reached.

[0246] The at least one positioning sensor for lateral alignment can also serve for distance setting. Accordingly, the positioning sensor is configured for sensing the distance between the sensor and the signal light or another component of the spinning position, such as the ring rail. This allows to precisely position the yarn breakage handling device in a determined distance to said component of the spinning position and thus to the spinning position in general terms.

[0247] However, said positioning sensor for distance setting can also be a separate position sensor. This means, a first positioning sensor is used for lateral positioning and a second positioning sensor is used for distance positioning.

[0248] The above mentioned positioning sensor for lateral positioning of the yarn breakage handling device, in particular in case of a camera, can also have the function of a malfunction localisation sensor, in particular of a yarn breakage localisation sensor, which is based on detecting a light signal emitted from the spinning position monitoring system on a spinning position, as described above.

[0249] The above mentioned positioning sensor for lateral positioning of the yarn breakage handling device, in particular in case of a camera, can also be configured for providing navigation information for navigation of the yarn breakage handling device, in particular along a machine side. Said navigation information being not limited to information for detailed lateral positioning or detailed positioning in distance in front of the spinning position based on a reference point as described above.

[0250] The camera forming one of the above mentioned sensors, e.g. for collecting navigation information, e.g. a position sensor or e.g. a malfunction localisation sensor, can be a stereo camera for generating stereoscopic images, i.e. stereoscopic information. This way the yarn breakage handling device has stereoscopic vision for (in particular detailed) navigation and in particular positioning.

[0251] It is also possible that a sensor for providing navigation information, a sensor for positioning the device in front of a spinning position or a malfunction localisation sensor as described above are configured for detecting spindle defects. However the spindle defect sensor can also be a separate sensor on the yarn breakage handling device. Based on a detected spindle defect in connection with a yarn breakage at the same spinning position the yarn breakage handling device can decide whether the yarn breakage shall be rectified or not. I.e. whether it is worth to rectify such a yarn breakage.

[0252] The above mentioned robot arms can be moved hydraulically, pneumatically, or electrically. Accordingly, a robot arm can comprise at least one hydraulic cylinder (hydraulic driven) or at least one pneumatic cylinder (pneumatically driven) or at least one electric motor (electrically driven). Combination of the above mentioned drives are also possible.

[0253] The above mentioned robot arms can comprise at least one pivot joint, in particular several pivot joints.

[0254] The invention also concerns a system, comprising a yarn breakage handling device for automated resurrection of a yarn breakage in a ring spinning machine, as described above, and an individual spinning position monitoring system for detecting yarn breakages.

[0255] The individual spinning position monitoring system comprises a yarn breakage sensor per spinning position for detecting a yarn breakage.

[0256] The yarn breakage sensors are designed for detecting the movement of the traveller. For example a movement stop of the traveller is an unmistakable sign of a yarn breakage.

[0257] The yarn breakage sensor can be an optical sensor, a magnetic sensor or a capacitive sensor. All three types of sensors are designed to detect whether the moving traveller is passing the sensor. Each time the traveller is passing the sensor a sensor signal is generated. A yarn breakage is detected by a missing signal which is the result of a standstill of the traveller and thus of a yarn breakage.

[0258] In particular, the yarn breakage sensor is arranged on the ring rail.

[0259] The individual spinning position monitoring system can also be designed for detecting spindle defects. Accordingly, the individual spinning position monitoring system comprises in particular at least one further sensor for detecting a spindle defect. The further sensor can be an optical sensor, such as a camera.

[0260] However, a spindle defect, such as a slipping spindle, an idle spindle or a rogue spindle can also be detected by the yarn breakage sensor which monitors the movement of the traveller.

[0261] In particular, the individual spinning position monitoring system comprises signal lamps/signal lights for indicating a yarn breakage by emitting a light signal, e.g. of a specific colour, as e.g. a red light. At each spinning position, in particular at the front side of the ring rail, such a signal lamp is arranged. The signal lamp can be integrated into the yarn breakage sensor, which means sensor unit.

[0262] In an embodiment the system further comprises a (central) computer arrangement. The computer arrangement in particular contains a control unit.

[0263] The computer arrangement can be designed for navigating the yarn breakage handling device to the affected spinning position in the ring spinning machine for attending to a yarn breakage or another spindle defect upon detection by the spinning position monitoring system.

[0264] The computer arrangement can be designed for communicating information, such as navigation information, e.g. related to a yarn breakage occurrence at a spinning position detected by the individual spinning position monitoring system, to the yarn breakage handling device for further processing.

[0265] The computer arrangement can be designed for communicating basic navigation information, such as which spinning machine, which machine side, which machine section which bay/corridor and/or more precise which spinning position is affected of a yarn breakage based on yarn breakage information of the spinning position monitoring system.

[0266] The yarn breakage handling device can use this information for moving to the concerned, i.e. affected ring spinning machine, machine side, machine section, bay/corridor or more precise spinning position. However, the detailed navigation can be carried out by the yarn breakage handling device itself based on sensor data, that is to say navigation data, provided by sensors arranged on the yarn breakage handling device.

[0267] It is also possible that in case of several yarn breakages at the same time the basic navigation information from the external computer arrangement is used to decide which yarn breakage shall be attended at first based on the current position of the yarn breakage handling device. Usually, the closest yarn breakage shall be attended at first. However, it may also be the yarn breakage which lasts for the longest.

[0268] The yarn breakage handling device can make this decision itself by means of the internal computer appliance. However, the decision can also be made by the external computer arrangement which in this case commands the yarn breakage handling device which yarn breakage has to be attended at first.

[0269] The computer arrangement can be designed for operating, i.e. controlling the yarn breakage handling device in parts or fully. In other words the yarn breakage handling device can be controlled remotely.

[0270] The communication between the computer arrangement and the yarn breakage handling device is in particular wireless as described further below.

[0271] The computer arrangement can be part of the individual spinning position monitoring system. The computer arrangement can be integrated in the control unit of the ring spinning machine. However the computer arrangement in particular is designed as a separate arrangement.

[0272] In particular, the computer arrangement is operationally independent from the machine control of the ring spinning machine.

[0273] In particular, the computer arrangement is physically independent from the machine control of the ring spinning machine, respectively from the ring spinning machine.

[0274] The yarn breakage handling device can be designed for servicing one, two, three or a plurality of ring spinning machines. Accordingly the system is designed for servicing one, two, three or a plurality of ring spinning machines by a common yarn breakage handling device.

[0275] In a spinning mill ring spinning machines often are arranged next to each other wherein a service lane or corridor is formed between two neighbouring ring spinning machines.

[0276] The yarn breakage handling device can now be designed for travelling or patrolling along one, two or several of such service lanes.

[0277] If the yarn breakage handling device is intended for travelling or patrolling along two or several service lanes, then the yarn breakage handling device is designed for driving/travelling around the ring spinning machine on their head and/or foot end. Accordingly, the system is designed for driving the yarn breakage handling device around the ring spinning machine on the head or foot end.

[0278] In particular, the yarn breakage handling device can be designed to serve two opposing machine sides of two ring spinning machines, each machine side having a row of spinning positions. The said two machine sides, that is to say rows of spinning positions facing the same service lane. Accordingly, the system is designed for servicing said two rows of spinning positions by a common yarn breakage handling device.

[0279] In particular, the yarn breakage handling device can be designed for servicing two rows of spinning positions of a ring spinning machine, said two rows of spinning positions facing different service lanes. Accordingly, the system is designed for servicing said two rows of spinning positions by a common yarn breakage handling device.

[0280] The system can comprise one or more than one, i.e. several yarn breakage handling devices. In case of several yarn breakage handling devices the yarn breakage handling devices can operate independently, i.e. autonomously from each other.

[0281] In case of multiple yarn breakage handling devices, said devices can also be controlled by a common computer device. The common computer device in particular is designed to communicate with the computer appliances of the yarn breakage handling devices. The common computer device can be designed to communicate with the computer arrangement of the spinning monitoring system.

[0282] In an embodiment the common computer device corresponds to the computer arrangement of the spinning monitoring system.

[0283] In an embodiment the common computer device is arranged on one of the multiple yarn breakage handling devices, in particular is integrated into the computer appliance of one of the multiple yarn breakage handling devices.

[0284] The communication between the common computer device and the computer appliances of the yarn breakage handling devices, respectively between the common computer device and the computer arrangement of the spinning monitoring system in particular is wireless.

[0285] The common computer device in particular is designed to direct the yarn breakage handling devices to the spinning position affected by a yarn breakage. The common computer device in particular is designed to decide which yarn breakage handling device to prioritize to attend a spindle defect. The prioritizing can be made based on the shortest distance between one of the yarn breakage handling devices and the affected spinning position.

[0286] The invention also comprises a method for resurrection of a yarn breakage in a ring spinning machine using a yarn breakage handling device as described above.

[0287] The method comprises the following stages:

A: detecting a yarn breakage;

B: moving the device in front of the spinning position with the yarn breakage and aligning the device on the spinning position;

C: stopping the rotation of the spindle, in particular by means of the spindle stopper unit;

D: catching the yarn end from the cop, in particular by means of the yarn capturing unit;

E: threading the yarn through the traveller, in particular by means of the yarn threading unit;

F: threading the yarn through at least one yarn guiding element;

G: resuming of the rotation of the spindle;

H: piecing, i.e. joining, the yarn together with the fibre strand processed in the drafting arrangement.

[0288] With regard to stage A, the detection of the yarn breakage in particular happens by means of the malfunction localisation sensor, i.e. the yarn breakage sensor, on the yarn breakage handling device. The malfunction localisation sensor e.g. detects the light signal on the affected spinning position indicating a yarn breakage.

[0289] According to the detected yarn breakage the yarn breakage handling device is navigated to the affected spinning position and moved, i.e. positioned in front of the affected spinning position.

[0290] However, it is also possible that the yarn breakage handling device receives the data for navigating to an affected spinning position from an external computer appliance, as mentioned above.

[0291] In particular, the data transmission from an external computer appliance, be it navigation data, spinning position data, malfunction data or other data are transmitted wireless.

[0292] In general, the wireless transmission can be via a mobile communications network, via a wireless network, such as Wireless Local Area Network (WLAN) or Wireless Personal Area Network (WPAN), e.g. using radio waves, in particular UHF radio waves, such as Bluetooth.

[0293] However, preferably the yarn breakage handling device detects the yarn breakages autonomously.

[0294] With regard to stage B, the lateral aligning of the yarn breakage handling device in front of the spinning position is carried out in particular by using at least one optical positioning sensor, in particular a camera.

[0295] In particular, the yarn breakage handling device is moved until the at least one positioning sensor senses the centre of the light signal (source) and is positioned in a predetermined way relative to this centre. For example, the yarn breakage handling device is moved until the measuring path of the optical positioning sensor meets the centre of the light signal (source).

[0296] With regard to stage C, the spindle stopper unit stops the rotation of the spindle in particular by activating the spindle brake of the ring spinning machine by means of the spindle stopper. The spindle stopper exerts a mechanical force onto the spindle brake such that the actuator of the spindle brake is moved from a release position into a brake position.

[0297] In an embodiment of the invention the cop is lifted from the spindle following stage C and preceding step D by means of the grasping mechanism of the cop lifter unit.

[0298] In order to make room for lifting the spinning cop, if present, the lappet hook is lifted, i.e. pivoted upwards. Accordingly, this process step is carried out before lifting the spinning cop from the spindle.

[0299] In particular, the lifting of the lappet hook is carried out after stopping the spindle rotation.

[0300] The lifting of the lappet hook is carried out by means of the lappet hook lifter of the lappet hook lifter unit, which pushes the lappet hook upwards in a inactive position outside the mounting path of the spinning cop onto the spindle.

[0301] In case the lappet hook lifter is mounted on a robot arm, the lappet hook lifter is moved by the robot arm which is actuated by the moving and positioning mechanism.

[0302] In order to lift the spinning cop from the spindle, the insertion tool of the grasping mechanism is engaged into the interior of the cop tube from above, according to a further development of present invention.

[0303] Following, the expansion member of the insertion tool is expanded within the tube and creates a frictional connection between the insertion tool and the tube of the spinning cop.

[0304] In a following step the grasped spinning cop is lifted from the spindle. The lifting of the spinning cop from the spindle has the purpose that the spinning cop or at least its section with the yarn windings is arranged above the moving ring rail. This because, only a spinning cop which is arranged above the ring rail ensures a successful locating, attracting and picking of the yarn end on the spinning cop.

[0305] In case the grasping mechanism is mounted on a robot arm, the grasping mechanism is moved by the robot arm which is actuated by the moving and positioning mechanism.

[0306] With regard to stage D, the yarn attracting and picking mechanism is moved in front of the spinning cop.

[0307] In order to locate the yarn end on the cop, the yarn attracting and picking mechanism, in particular the yarn suction tube of the yarn capturing unit, is moved up and down along the spinning cop. The up and down movement is in particular parallel to the longitudinal axis of the cop tube.

[0308] Simultaneously, the rotation mechanism of the cop lifter unit makes the spinning cop rotate around its tube axis.

[0309] Thus, by rotation the spinning cop and by the up and down movement of the yarn attracting and picking mechanism the yarn attracting and picking mechanism is able to search the whole surface of the spinning cop.

[0310] In case of a suction tube, the front opening of the yarn suction tube is directed to the surface of the spinning cop. Due to the suction exerted on the surface of the spinning cop the loose yarn end is lifted from the surface and sucked into the yarn suction tube through the front opening as soon as the yarn suction tube approaches the yarn end.

[0311] In case that bristles or a brush are provided for mechanically detaching the yarn end, the yarn end is detached by the bristles or brush prior the passing by of the yarn suction tube. This for example, happens automatically in case the bristles or brush are attached on the yarn suction tube.

[0312] In case the yarn attracting and picking mechanism is mounted on a robot arm, the yarn attracting and picking mechanism is moved by the robot arm which is actuated by the moving and positioning mechanism.

[0313] Once the yarn suction tube has attracted the yarn end, the yarn end is sucked into the yarn suction tube through the front opening and passes through the yarn suction tube such that a yarn section is received within the yarn suction tube and extending along the tube axis.

[0314] For creating the suction at the front opening an air flow is discharged through at least one air inlet into the interior of the yarn suction tube. The air flow has a flow component towards the rear opening of the yarn suction tube, such that the air flows towards the rear opening. Due to a venturi effect the gas flow creates a suction at the front opening.

[0315] In an embodiment of the invention, the yarn end is sucked in through the front opening, passes through the yarn suction tube and leaves the yarn suction tube through the rear opening.

[0316] Due to the flow component towards the rear opening of the yarn suction tube, the yarn end which is sucked into the yarn suction tube through the front opening is blown out through the rear opening.

[0317] After the yarn end is sucked into the yarn suction tube the holding mechanism is activated for holding, in particular clamping, the yarn, in particular in the interior, i.e. in the channel of the yarn suction tube or a channel joining the yarn suction tube at the rear end.

[0318] In an embodiment the clamping element of a clamping mechanism is moved transverse to the yarn suction tube axis thereby traversing the channel and thus entrain the yarn passing along the channel. The yarn is clamped within the channel between the clamping element and a die that cooperates with clamping element.

[0319] Once the yarn is held by the holding mechanism, the overlength, i.e. excess length containing the free yarn end, which in particular hangs out of the rear end of the channel can be cut by the separating mechanism.

[0320] In an embodiment the cutting knife of a yarn cutting mechanism is moved transverse to the yarn suction tube axis, thereby traversing the channel and thus entrain the yarn passing along the channel. The yarn is seized within the channel between the cutting knife and a die that cooperates with cutting knife and thus the excessive length of yarn is cut.

[0321] Following, the yarn capturing unit, i.e. its yarn holding mechanism is positioned or moved in a position in which the yarn is led away from the spinning cop towards the yarn breakage handling device. In particular, the yarn is led away perpendicular to the orientation of the ring rail or at least essentially perpendicular to the orientation of the ring rail. Essentially perpendicular in particular means in an angle of 70° to 90° (angle degree).

[0322] With regard to stage E the yarn holding mechanism of the yarn threading unit is positioned such that the yarn holding mechanism can capture a stretch of yarn extending between the spinning cop and the yarn holding mechanism of the yarn capturing unit.

[0323] In an embodiment the yarn capturing unit hands over the stretch of yarn to the holding mechanism.

[0324] In particular, said stretch of yarn is introduced into the receiving recesses of the two yarn holding fingers and comes to lie between the two yarn holding fingers. In particular, the yarn is secured on the yarn holding fingers by the securing elements. In particular, the stretch of yarn is spanned and most particular also tensioned between the two yarn holding fingers by securing it.

[0325] In order to hand over the stretch of yarn to the holding fingers the yarn holding mechanism of the yarn threading unit is positioned such that the two yarn holding fingers are oriented perpendicular to the course of the yarn spanned between the yarn holding, i.e. clamping mechanism of the yarn capturing unit and the cop package. In other words, the axis running through the holding points on the holding fingers is parallel to the course of the yarn spanned between the yarn holding, i.e. clamping mechanism of the yarn capturing unit and the cop package.

[0326] For capturing the stretch of yarn by the yarn holding fingers said course of yarn is in particular oriented perpendicular or essentially perpendicular that is to say at an angle of at least 60° relative to the longitudinal direction of the ring rail.

[0327] In other words, when said stretch of yarn comes to lie between the yarn holding fingers the stretch of yarn is in particular oriented transverse or essentially transverse to the orientation of the ring rail.

[0328] In particular, said stretch of yarn is actively positioned by the yarn capturing unit, in particular by its holding mechanism onto the holding fingers. However, it is also possible that the yarn holding mechanism of the yarn threading unit is moved towards the yarn and actively takes over the stretch of yarn.

[0329] The holding mechanism is configured such that the stretch of yarn is spanned and tensioned between the holding fingers by securing the stretch of yarn on the yarn fingers.

[0330] In an embodiment the stretch of yarn comes to lie in the receiving recesses of the holding fingers, in particular is inserted into the receiving recesses of the holding fingers.

[0331] The insertion of the yarn into the receiving recesses can take place by moving the yarn capturing unit, in particular its yarn holding mechanism, and thus moving the yarn towards the holding mechanism, in particular towards the holding fingers, of the yarn threading unit.

[0332] The insertion of the yarn into the receiving recesses can also take place by moving the holding device, in particular the holding fingers, of the yarn threading unit towards the yarn extending between the yarn holding mechanism of the yarn capturing unit and the cop.

[0333] A combined movement of the above mentioned mechanism is also possible.

[0334] In an embodiment a moving securing element is moved transverse to the longitudinal axis of each holding finger across the receiving recess and takes along, i.e. entrains the stretch of yarn. The yarn is deflected out of the recess in moving direction of the securing element. As a result, the stretch of yarn, that is to say the yarn section between the holding fingers is shifted that is to say relocated in the moving direction of the securing element. Thereby the shifted stretch of yarn section is tensioned. In this process yarn length can be drawn in through the receiving recess from outside the stretch of yarn spanned between the two yarn holding fingers.

[0335] In particular, the securing of the yarn on the holding fingers is achieved by the deflection of the yarn on the holding finger, in particular on the receiving recess. In particular, the yarn is deflected at a sharp angle. The deflection can have the form of a kink. The deflection occurs via a deflection point, in particular via a deflection edge on the holding finger.

[0336] The deflection of the yarn increases the friction which hinders the slipping of the yarn or at least increases the tensile force necessary for slipping of the yarn. Thus, the deflection has a securing, in particular a holding or fixation effect. Generally, such a deflection can also be carried out by other mechanism than described in this patent application.

[0337] In particular, the yarn is not fixedly held on the holding finger. The yarn rather can slip on the holding finger if a certain tensile force acting on the yarn is exceeded. As a result the risk of yarn breaks during threading the yarn can be reduced.

[0338] In an embodiment the yarn is entrained by an entrainment recess or deepening on the securing element. In particular, the entrainment recess is arranged in the free end section and in particular at the front end side of the securing element.

[0339] Once the yarn is held by the holding fingers, i.e. secured on the holding fingers, the holding mechanism and thus the holding fingers with the stretch of yarn spanned therebetween are moved towards the traveller guiding ring accommodating the traveller.

[0340] The holding mechanism is positioned such that the yarn section spanned between the holding fingers runs parallel to a tangent of the traveller guiding ring. The holding mechanism in particular is positioned such that the yarn section spanned between the holding fingers runs parallel or at least essential parallel to the ring rail. Essential parallel means with a deviation of at maximum 10° (angle degrees).

[0341] The traveller is positioned by means of the traveller positioning mechanism in front of the spindle such that it faces the stretch of yarn spanned between the yarn holding fingers.

[0342] In an embodiment a first traveller positioning member is positioned on the left side of the spindle and a second traveller positioning member is positioned on the right side of the spindle.

[0343] In an embodiment the traveller is positioned by air blasts discharged from the traveller positioning member.

[0344] Once the traveller is positioned on the front side of the traveller guiding ring, the yarn is inserted into the traveller by means of the yarn holding mechanism. Hereto the yarn holding mechanism is moved forward and as the case may be also backwards as well as upwards and as the case may be also downwards, such that the held stretch of yarn is moved through the opening of the traveller and thus threaded into the traveller.

[0345] Once the yarn is threaded into the traveller, the held stretch of yarn is released from the yarn holding mechanism, such that the yarn can separate from the yarn holding mechanism, in particular from the yarn holding fingers. For example, the securing elements can be moved into a releasing position in which the yarn is no longer secured on the yarn holding fingers.

[0346] However, the yarn is still held by the yarn holding mechanism of the yarn capturing unit, which holding mechanism was also holding the yarn while it was held by the yarn holding mechanism of the yarn threading unit.

[0347] It is in general a notable aspect of present invention that - independent of the design of the yarn capturing unit and the yarn threading unit - the yarn in particular is held by the yarn capturing unit, i.e. by its yarn holding mechanism, throughout the whole process starting with picking up the yarn from the spinning cop until the discharge of the yarn for piecing, i.e. joining it with a fibre strand.

[0348] This results in the fact, that the yarn is held by the yarn capturing unit as well as by the yarn threading unit during the threading of the yarn into the traveller.

[0349] Once the yarn is inserted into the traveller and is released from the yarn holding mechanism of the yarn threading unit, the yarn end section held by the yarn capturing unit is moved upward, in particular towards the drafting arrangement, by the yarn capturing unit, i.e. by its yarn holding mechanism.

[0350] With regard to stage F, in one ore several process steps the yarn is threaded into the at least one yarn guiding element arranged between the spindle and the delivery rollers of the drafting arrangement.

[0351] However, between stage D and stage F, in particular during stage E the cops is lowered onto the spindle again by the cop lifter unit and resumes its spinning position. The cop lifter unit releases the cop and in particular retracts from the cop.

[0352] Furthermore, after lowering the cops onto the spindle, but in any case before stage F, the lappet hook is moved, in particular pivoted back into its spinning position. For this purpose the lappet hook lifter releases the lappet hook and in particular retracts from the lappet hook. The lappet hook resumes its spinning position again.

[0353] Usually a balloon control ring is arranged above the spindle. Accordingly, the yarn is first threaded into the balloon control ring on its way up towards the drafting arrangement.

[0354] Usually a lappet hook is arranged between the spindle and the delivery rollers of the drafting arrangement, that is to say between a balloon control ring - if present - and the delivery rollers of the drafting arrangement. Accordingly, the yarn is threaded into the lappet hook on its way up towards the drafting arrangement. If a balloon control ring is present the yarn is threaded into the lappet hook after threading into the balloon control ring.

[0355] After threading the yarn into all yarn guiding elements, in particular after threading the yarn into the lappet hook the yarn is moved towards the drafting arrangement for carrying out the piecing process.

[0356] With regard to stage G, the rotation of the spindle is resumed before, in particular shortly before the piecing process is carried out or at the same stage as the piecing process is carried out. For resuming the rotation of the spindle the spindle stopper unit releases the halt of the spindle so that the spindle can resume rotation.

[0357] In particular, the spindle stopper arm release the spindle brake thereby resuming the rotation of the spindle.

[0358] With regard to stage H, the yarn is united, i.e. joined with a textile strand processed in the drafting arrangement. In other words: the yarn is pieced.

[0359] The piecing can be carried out between the yarn end section and the fibre strand leaving the delivery rollers of the drafting arrangement. I.e. the piecing, as viewed in process direction, takes place subsequent to the delivery rollers of the drafting arrangement.

[0360] In this case the yarn breakage handling device, i.e. its robot arrangement can comprise a yarn piecing unit with a piecing mechanism for piecing the yarn.

[0361] The yarn piecing unit, i.e. its piecing mechanism in particular is designed for introducing a twist into the joined fibre strand. The joined fibre strand means the yarn end section and the drafted roving which are brought together, i.e. laid over each other for piecing.

[0362] In particular, the yarn piecing unit comprises a moving and positioning mechanism for moving and positioning the piecing mechanism.

[0363] The yarn piecing unit can comprise at least one robot arm, in particular an articulated robot arm. The piecing mechanism is arranged on a robot arm, in particular in a distal end of the robot arm. In this case the moving and positioning mechanism in particular is configured for actuating the corresponding robot arm.

[0364] In an embodiment, the yarn piecing unit, respectively its piecing mechanism can be arranged on a common robot arm together with at least one of a:

• lappet hook lifter unit;
• cop lifter unit or
• yarn capturing unit.

[0365] The piecing mechanism can also be integrated into the lappet hook lifter of the lappet hook lifter unit.

[0366] The piecing mechanism can also be integrated into the grasping mechanism of the cop lifter unit.

[0367] The piecing mechanism can also be integrated into the yarn attracting and picking mechanism of the yarn capturing unit.

[0368] The piecing mechanism can comprise pneumatic means. The piecing mechanism can comprise mechanical means. The piecing mechanism can comprise magnetic means. Mechanical means can e.g. comprise fingers which are moveable relative to each other.

[0369] The yarn piecing unit can be designed for holding and moving the yarn end section towards the piecing area subsequent to the delivery rollers of the drafting arrangement.

[0370] However, it can also be the case that the yarn end section is held and moved towards the piecing area by the yarn capturing unit wherein the piecing process is carried out by the yarn piecing unit.

[0371] The piecing of can be made by keeping a loose end of a yarn close to drafted roving and applying a rotation to the yarn and/or the drafted roving. By this, the fibrous loose end of the yarn and the fibrous drafted roving can get caught up and can get twisted into each other, which can result in a twisted connection of the loose end of the yarn and the drafted roving.

[0372] The piecing can be performed mechanically, for example wherein the twist is applied mechanically. For example, the loose end of the yarn can be held by two fingers and the finger can move in opposite direction, thus inducing a rotation of the yarn and of its loose end. In particular, the two fingers can change the opposing directions, thereby rotating the yarn back and forth.

[0373] The piecing can be performed pneumatically. For example, the loose end of the yarn and/or the drafted roving can be sucked into a suction device of the piecing mechanism and/or of the ring spinning machine. A rotation of the yarn and/or the drafted roving can be induced pneumatically, e.g. by a suction. A rotation of the yarn and/or the drafted roving can be induced e.g. by a vortex flow.

[0374] However, in a preferred embodiment the held yarn end section is moved, i.e. positioned behind the delivery rollers as viewed against the process direction and laid over the drafted roving behind the front delivery rollers. In particular, the yarn end section is moved, i.e. positioned, between the delivery rollers and the drafting aprons. Accordingly, the yarn end section is unified with the drafted fibre strand, i.e. roving.

[0375] This piecing method described above has the advantage that the yarn end section passes the delivery rollers together with the fibre strand and thus is immediately twisted together with the fibre strand. This way, no additional mechanical means for joining the yarn end section to the fibre strand or even an auxiliary yarn are necessary.

[0376] After the yarn end section is brought together with the drafted roving of the drafting arrangement, i.e. after the piecing is completed, the yarn capturing unit, i.e. its yarn holding mechanism and/or as the case may be the yarn piecing unit, i.e. its piecing mechanism releases the yarn, such that the spinning process can be resumed.

[0377] Once the piecing process is completed and the spinning process is resumed the robot arms of the units discussed above in particular are retracted into their starting, i.e. initial position, if not yet the case.

[0378] The expression "air" in connection with the above described devices producing an air flow or pressurised/compressed air, has to be understood broadly and also encompasses any kind of suitable gas or gas mixture. However, for economical reasons air would be most suitable to be used.

[0379] Pressurized air for producing air flows or air blasts as described above can be produced centrally on the yarn breakage handling device. Hereto, the yarn breakage handling device can comprise a compressor for producing pressurised air and a storage cylinder for storing the pressurised air.

[0380] However, it is also possible that the traveller positioning mechanism, the yarn attracting and picking mechanism or the cop lifter unit in each case can comprise a module for producing an air flow or blast or pressurised air in situ.

[0381] The present invention ensures a quick restoration of the yarn spinning process on a spinning position after a yarn breakage.

[0382] Other aspects, advantages, further developments and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses an exemplary embodiment of the invention. The drawings schematically show:

Figure 1:

a lateral view of a spinning position in a ring spinning machine;

Figure 2:

a system for resurrection of yarn breakages in a ring spinning machine according to the invention;

Figure 3:

a robot arrangement of a device for automated resurrection of a yarn breakage according to the invention at the first stage comprising the detection of a yarn breakage and stopping of the spindle;

Figure 4:

the robot arrangement according to figure 3 at the next stage comprising the lifting of the lappet hook and gripping of the cop;

Figure 5:

the robot arrangement according to figure 3 at the next stage comprising the lifting of the cop from the spindle;

Figure 6:

the robot arrangement according to figure 3 at the next stage comprising the attracting and picking the yarn end from the cop;

Figure 7:

the robot arrangement according to figure 3 at the next stage comprising the capturing of a yarn section by the yarn threading unit;

Figure 8:

the robot arrangement according to figure 3 at the next stage comprising the lowering of the cop onto the spindle;

Figure 9:

the robot arrangement according to figure 3 at the next stage comprising the positioning of the traveller and the threading of the yarn into the traveller;

Figure 10:

the robot arrangement according to figure 3 at the next stage comprising the retraction of the yarn threading unit from the traveller guiding ring and the lowering of the lappet hook;

Figure 11:

the robot arrangement according to figure 3 at the next stage comprising the releasing of the yarn from the yarn threading unit and the releasing of the cops and retraction of the cop lifter unit;

Figure 12:

the robot arrangement according to figure 3 at the next stage comprising the threading of the yarn into the lappet hook;

Figure 13:

the robot arrangement according to figure 3 at the next stage comprising the piecing of the yarn with the fibre strand of the drafting arrangement;

Figure 14:

the yarn attracting and picking mechanism of the yarn capturing unit;

Figure 15:

the yarn holding and traveller positioning mechanism of the yarn threading unit;

Figure 16:

a yarn piecing unit activating the roving stop motion of a ring spinning machine.

[0383] Basically, in the figures the same features have the same reference numerals.

[0384] In a spinning position 4 of a ring spinning machine 1 as shown in figure 1 the roving 22 is unwinded from a roving bobbin 20 and transported through a drafting arrangement 16 in which the roving 22 is drafted to a fibre strand 19. The drafted roving leaves the drafting arrangement 16 as a fibre strand 19 through a pairing of delivery rollers 17, 18, also called front rollers, which form a nip. The fibre strand 19 is transported towards a rotating, i.e. revolving spindle 6. Between the delivery rollers 17, 18 and the spindle 6 the fibre strand 19 is twisted into a yarn 8. The transport direction of the fibre material, i.e. the process direction of the fibre material is top down.

[0385] Close to the exit of the delivery rollers 17, 18 the suction pipe 21 of a suction device is arranged. The suction pipe 21 serves for sucking away fibre debris and dust and in particular for sucking away the fibre strand 19 discharged at the delivery rollers 17, 18 in case of a yarn breakage.

[0386] Between the delivery rollers 17, 18 and the spindle 6 yarn guiding elements such as a lappet hook 14 and a balloon control ring 15 are arranged. In process direction the lappet hook 14 is arranged subsequent to the delivery rollers 17, 18. In process direction the balloon control ring 15 is arranged subsequent to the lappet hook 14.

[0387] On the spindle 6 a tube is arranged on which the windings of the yarn are deposited. The tube together with the yarn windings on it form the so called spinning cop or cop package or simply cop 7.

[0388] The spindle 6 is surrounded by a traveller guiding ring 10 on which a traveller 11 is moveably arranged. The traveller guiding ring 10 is arranged on a ring rail 5. The spindle 6 and hence the cop 7 is led through an opening in the ring rail 5. Usually the spinning positions 4 on one machine side have a common ring rail 5. For depositing the yarn windings along the longitudinal extension of the tube, the ring rail 5 is moveable up and down during the spinning process.

[0389] For producing the yarn windings on the spinning cop 7 the yarn 8 is threaded through the traveller 11 which deflects the yarn provided from above laterally towards the spinning cop 7.

[0390] Usually the spindles 6 of a spinning machine 1 or of at least one machine side or machine section of the spinning machine are driven by a common drive. The driving force is transmitted to the spindles 6 by means of driving belts 13 (see also figures 3-12). In order to stop an individual spindle 6 during the spinning process at each spindle 6 a spindle brake 12 is arranged. The spindle brake 12 comprises a braking element which can be moved, in particular pivoted towards the rotating spindle 6 and thus forming a friction contact to the spindle 6.

[0391] However, it is also known to drive the spindles by individual spindle drives which are arranged at the spindle. The spindle drives e.g. comprise an electric motor.

[0392] The system for resurrection of yarn breakages in a ring spinning machine 1 as shown in figure 2 comprises an individual spinning monitoring system 3. The individual spinning monitoring system 3, which is well known in the state of the art, contains a yarn breakage sensor 3a at each spinning position 4. The yarn breakage sensor 3a is designed for detecting the movement and in particular the non-movement of the traveller 11 indicating a yarn breakage. The sensor is equipped with an indicator lamp/signal lamp 3b designed for indicating a yarn breakage.

[0393] The individual spinning monitoring system 3 also comprises a central computer arrangement 2 for collecting and evaluating the measuring results of the yarn breakage sensor 3a. The central computer arrangement 2 can be part of the machine control of the spinning machine 1 or can be an independent device. The central computer arrangement 2 can be connected to the machine control or can operate autonomously from the machine control.

[0394] In present embodiment the central computer arrangement 2 contains means for communicating with a wireless communication device 23. However, the wireless communication device 23 can also be part of the central computer arrangement 2.

[0395] The computer arrangement 2 can contain a control unit for controlling the yarn breakage handling device 31 or parts of it.

[0396] The system can be designed such that the central computer arrangement 2 is able to communicate with a yarn breakage handling device 31 via the wireless communication device 23. The communication can be unidirectional, in particular from the central computer arrangement 2 to the yarn breakage handling device 31, or can be bidirectional.

[0397] The above mentioned the yarn breakage handling device 31 is the centrepiece of present invention. The yarn breakage handling device 31 is a movable physical unit which comprises the following functional units:

• robot arrangement 51 and
• transportation arrangement 141.

[0398] The robot arrangement 51 which will be described further below in more detail contains means for rectifying yarn breakages.

[0399] The transportation arrangement 141 serves for moving the yarn breakage handling device 31 including the robot arrangement 51 along the spinning positions of the ring spinning machine 1. The transportation arrangement 141 comprises rollers 143, in particular wheels, for rolling on the ground and a drive 142 for driving the yarn breakage handling device 31 that is to say the rollers 143.

[0400] The robot arrangement 51 which is arranged on the transportation arrangement 141 comprises the following units:

• a spindle stopper unit 61
• a lappet hook lifter unit 71
• a cop lifter unit 81
• a level verifying unit 91
• a yarn capturing unit 101 and
• a yarn threading unit 121.

[0401] The spindle stopper unit 61 serves for stopping the rotation of the spindle 6 and thus the cop package 7 during rectifying a yarn breakage. The spindle stopper unit 61 comprises a spindle stopper 64 that is arranged on a robot arm 63 which is movable by means of a moving and positioning mechanism 62 (only schematically indicated in figure 3).

[0402] The lappet hook lifter unit 71 serves for lifting the lappet hook 14 and thus for clearing the way for lifting the cop package 7 from the spindle 6 upwards. The lappet hook lifter unit 71 comprises a lappet hook lifter 74 that is arranged on a robot arm 73 which is movable by means of a moving and positioning mechanism 72 (only schematically indicated in figure 3).

[0403] The cop lifter unit 81 serves for lifting the cop package 7 from the spindle 6 upwards, in particular above the ring rail 5 so that the yarn capturing unit 101 can search the cop package 7 for the yarn end as described in detail further below. The cop lifter unit 81 comprises a grasping mechanism 84 that is arranged on a robot arm 83 which is movable by means of a moving and positioning mechanism 82 (only schematically indicated in figure 3).

[0404] The level verifying unit 91 serves for detecting the height level of the ring rail and for adjusting the position of the yarn threading unit 121 to the changing height level of the moving ring rail 5. The level verifying unit 91 comprises a ring rail sensor 94 for detecting the height level of the ring rail 5 or a change of said height level.

[0405] The yarn capturing unit 101 serves for capturing the yarn end from the cop package 7 and for guiding the yarn through the several piecing steps. The yarn capturing unit 101 comprises a yarn attracting and picking mechanism 104 as well as a yarn clamping mechanism 108 and a yarn cutting mechanism 109 that are arranged on a robot arm 103 which is movable by means of a moving and positioning mechanism 102 (only schematically indicated in figure 3).

[0406] The yarn threading unit 121 serves for threading the yarn into the traveller 11. The yarn threading unit 121 comprises a yarn holding and traveller positioning mechanism 127, 124 that are arranged on a robot arm 123 which is movable by means of a moving and positioning mechanism 122 (only schematically indicated in figure 3).

[0407] The yarn breakage handling device 31 further comprises a control unit 34 for controlling the robot arrangement 51, in particular the above mentioned mechanical units 61, 71, 81, 91, 101, 121 of the robot arrangement 51, and for controlling the transportation arrangement 141. The control unit 34 further serves for collecting and evaluating sensor data captured by the mentioned sensors 35, 36, 94.

[0408] In particular, the control unit 34 is part of a computer appliance of the yarn breakage handling device 31.

[0409] The functionalities and elements of the above mentioned mechanical units 61, 71, 81, 91, 101, 121 of the robot arrangement 51 are described further below in connection with the description of a yarn resurrection process in more details.

[0410] Such a yarn resurrection process is shown in figures 3 to 13, which represent the consecutive steps of said resurrection process.

[0411] As also shown in figure 2 the yarn breakage handling device 31 comprises cameras 36 for detecting yarn breakages in spinning positions along the lateral side of the ring spinning machines. In present case a first camera 36 is directed to a machine side of a first spinning machine and a second camera 36 is directed to a opposite machine side of a second spinning machine while the yarn breakage handling device 31 is patrolling along the corridor between the two spinning machines.

[0412] In case of a yarn breakage the individual spinning monitoring indicates this by means of a light signal emitted by the signal lamp 3b on the spinning position. The light signal indicating a yarn breakage can be the light up itself or a specific colour of the light or a flashing of the light. The light signal indicating a yarn breakage on a spinning position 4 is now detected by the camera 36.

[0413] Alternately, the camera can be configured to see, i.e. to detect the presence of a yarn directly. The camera directly detects if no yarn is running and wound up onto a cop so that the yarn breakage handling device can move towards that spinning position to attend the yarn break. In this case an individual spinning position monitoring system is not needed.

[0414] After detecting the light signal of the signal lamp 3b the yarn breakage handling device 31 moves autonomously towards the spinning position 4 of the spinning machine 1 having a yarn breakage. The yarn breakage handling device 31 positions itself in front of said spinning position 4 in an operation position.

[0415] Hereto the yarn breakage handling device 31 comprises a further camera 35 which - in operation position of the yarn breakage handling device 31 - is facing the spinning position 4. The camera serves for exactly positioning, in particular lateral positioning, of the yarn breakage handling device 31 in front of the spinning position 4. The light signal of the signal lamp 3b of the individual spinning monitoring system 3 serves as reference point for precise positioning of the yarn breakage handling device 31 in front of the spinning position 4. Accordingly, the camera 35 is able to detect the light signal. This means, the camera 35 can also be used for detecting a yarn breakage on a spinning position 4 of the spinning machine 1, while the yarn breakage handling device 31 is patrolling along the machine side of the ring spinning machine 1.

[0416] However, other optical sensors than cameras can be used for detecting a yarn breakage, i.e. for detecting the light signal of the signal lamp 3b of the individual spinning monitoring system 3. Furthermore, it is also possible that the information of a yarn breakage in a spinning position 4 is transmitted to the yarn breakage handling device 31 by the individual spinning monitoring system 3 in a wireless manner, e.g. via the computer arrangement 2. Based on this information the yarn breakage handling device 31 is capable of navigating to said spinning position 4 autonomously.

[0417] According to figure 3 after detecting a yarn breakage, the yarn breakage handling device 31 with its robot arrangement 51 is positioned in front of the spinning position 4 having a yarn breakage in an operation position. The positioning is made by means of the camera 35 which is directed towards the signal lamp 3b which emits a light signal that serves as a spatial reference point.

[0418] After reaching its operation position the spindle stopper 64 of the spindle stopper unit 61 is moved towards the spindle brake 12 by moving the corresponding robot arm 63. The spindle stopper 64 is brought in contact with the spindle brake 12 such that the spindle brake 12 is activated and stops the rotation of the spindle 6. However, it is also possible that the spindle stopper 64 directly forms a frictional contact with the spindle 6 and thus is directly stopping the rotation of the spindle 6.

[0419] Before, after or simultaneously with the spindle stop the lappet hook lifter 74 of the lappet hook lifter unit 71 is moved towards the lappet hook assembly 14 by moving the corresponding robot arm 73. The lappet hook lifter 74 lifts the lappet hook 14 which swivels upwards in a passive position around a swivel axes. By lifting the lappet hook 14 the way for lifting the cop package 7 from the spindle 6 upwards is cleared.

[0420] In a subsequent step the grasping mechanism 84 of the cop lifter unit 81 is moved towards the top of the cop package 7, i.e. towards the top of its tube as shown in figure 4. The grasping mechanism 84 comprises an insertion tool 85 with an expansion member 86 which is inserted into the upper end section of the tube of the cop package 7.

[0421] After inserting the insertion tool 85 into the tube the expansion member 86 is expanded and forms a frictional connection and/or form fit in the interior of the tube. Subsequently, the grasping mechanism 85 is moved upwards and thus the cop 7 is lifted from the spindle 6 as shown in figure 5. Usefully, the cop 7 is lifted to such an extent that all yarn windings on the cop 7 are arranged above the traveller guiding ring 10.

[0422] Now, the cop 7 is exposed to such an extent that the yarn attracting and picking mechanism 104 of the yarn capturing unit 101 can be moved towards the cop package 7 by moving the corresponding robot arm 103 as shown in figure 6.

[0423] The yarn attracting and picking mechanism 104 comprises a yarn suction tube 105 with a front opening 106 which is directed towards the cop package 7 and on which an induced draft is applied (see also figure 14).

[0424] The yarn suction tube 105 is now moved up and down along the cop package 7. In the same time the cop package 7 is slowly rotated around its axis by the cop lifter unit 81. For this purpose the insertion tool 85 is rotated around its axis by means of a rotation mechanism on the cop lifter unit 81. This way the yarn capturing unit 101 is able to search to whole surface of the yarn windings on the cop package 7 for the loose yarn end. As soon as the yarn suction tube 105 approaches the loose yarn end on the cop 7 the loose yarn end is sucked into the yarn suction tube 105 and thus picked from the surface of the cop package 7.

[0425] Mechanical means, such as brushes or bristles, can be provided to mechanical loosen the yarn end from the cop surface which facilitates the aspiration of the yarn end by the yarn suction tube (not shown). The mechanical means can be attached at the yarn capturing unit 101, in particular on the yarn suction tube 105.

[0426] The induced draft, i.e. the suction is produced by an air flow which is led into the tube, i.e. the tube channel or passage, through at least one lateral air inlet 112. The air inlet 112 that is to say the inlet channel is designed such that the air flow 113 has an axially parallel flow component which is directed to the rear opening 107 of the yarn suction tube 105. In particular, several air inlets 112 can be arranged on the periphery yarn suction tube 105, in particular around the periphery of the yarn suction tube 105. The air flow 113 can be produced by pressurised air discharged through the inlets 112 into the yarn suction tube 105.

[0427] As the air flow 113 in the yarn suction tube 105 is directed to the rear opening 107 of the yarn suction tube 105 an underpressure is produced at the front opening 106 and thus an induced draft. The yarn end which is sucked into the yarn suction tube 105 via the front opening 106 is drawn through the yarn suction tube 105 due to the flow conditions within the yarn suction tube 105 and leaves the yarn suction tube 105 through a rear opening 107.

[0428] In other words, the above mentioned air flow conditions within the yarn suction tube 105 result in the loose yarn end being sucked into the yarn suction tube 105 at the front opening 107, being transported through the yarn suction tube 105, i.e. through its channel or passage, and discharged at the rear opening 107 as long as yarn length 8 is provided.

[0429] At the rear end or in the rear end section of the yarn suction tube 105 a yarn holding mechanism 108 is arranged for holding the yarn end section which is sucked into the yarn suction tube 105 as shown in figure 14. In present case the yarn holding mechanism 108 is a yarn clamping mechanism which comprises a clamping element that is moveable transverse to the tube axis 110 across the passage through which the yarn end section is transported and cooperates with a counterpart on the other side of the passage for clamping the yarn. For clamping the yarn the clamping element is moved across the passage captures the yarn in the passage and clamps the yarn between the clamping element and the counterpart.

[0430] Once the sucked in yarn end section is clamped by the yarn clamping mechanism 108 a yarn separating mechanism 109 which is also arranged at the rear end or in the rear end section of the yarn suction tube 105 separates the excess yarn length which emerges from the rear opening 107 of the yarn suction tube 105 from the clamped yarn.

[0431] In present embodiment the yarn separating mechanism 109 is a yarn cutting mechanism that cuts off the excess yarn length which emerges from the rear opening 107 of the yarn suction tube 105 from the clamped yarn. The yarn cutting mechanism 109 comprises a cutting element, e.g. a knife, i.e. a cutting blade, which is also moveable transverse to the tube axis 110 across the passage through which the yarn end section is transported and cooperates with a counterpart on the other side of the passage for cutting the yarn. For cutting the yarn the cutting element is moved across the passage captures the yarn in the passage and cuts off the yarn pinched between the cutting element and the counterpart.

[0432] However, the yarn separating mechanism 109 is not an essential feature of present invention.

[0433] The yarn holding mechanism 108 can be integrated into the yarn suction tube 105. The yarn holding mechanism 108 can be a module which is attached at the rear end of the yarn suction tube 105 and which forms an extension of the passage. The same applies to the yarn separating mechanism 109.

[0434] The yarn holding and separating mechanism 108, 109 can be combined, in particular can be a combined module.

[0435] In particular, the yarn end section is held, i.e. clamped as soon as it passes the yarn holding mechanism 108 through the passage. This way it is ensured that the picked up yarn end section can not escape the yarn suction tube 105.

[0436] The yarn attracting and picking mechanism 104 also contains a yarn detection sensor 111 for detecting the presence of a yarn 8 in the passage, i.e. whether the yarn end has been picked up and properly sucked into the yarn suction tube 105. The yarn detection sensor 111 is arranged downstream the yarn holding and separating mechanism 108, 109 in the rear end or in the rear end section of the yarn suction tube 105. The yarn detection sensor 111 in particular is an optical sensor.

[0437] As soon as the yarn detection sensor 111 detects a yarn in the passage, the yarn holding mechanism 108 can be activated and the yarn can be held, i.e. clamped. At this point in time the yarn attracting and picking step is completed and the yarn breakage handling device 31 can initiate the next step. The holding, i.e. clamping of the yarn end section allows the movement of the yarn capturing unit 101 without the yarn end section being drawn out of the yarn suction tube 105. This is in particular important in connection with the following process steps.

[0438] The separating, i.e. cutting of the excess yarn length hanging out of the rear opening 107 of the passage can take place at any time before the yarn piecing step is started. However, the separating, i.e. cutting of the excess yarn length in particular serves for the process safety as a loose yarn section may interfere with the robot mechanics. Therefore, the separating, i.e. cutting step preferably takes place shortly after holding, i.e. clamping the yarn end section. It is self-explanatory that the yarn is separated, i.e. cut at a location downstream the holding, i.e. clamping point towards the rear opening 107 of the passage.

[0439] Once the loose yarn end has been picked up by the yarn attracting and picking mechanism 104 and held, i.e. clamped by the yarn holding, i.e. clamping mechanism 108 of the yarn capturing unit 101, the yarn capturing unit 101 is retracted from the cop package 7 together with the yarn end section. In succession the yarn holding mechanism 127 of the yarn threading unit 121 comes into action as shown in figure 7.

[0440] The yarn holding mechanism 127 of the yarn threading unit 121 comprises two yarn holding fingers 128a, 128b (see also figure 15) which capture the yarn 8 such that a stretch of yarn from the yarn section arranged between the yarn holding, i.e. clamping mechanism 108 and the cop package 7 is spanned between the two yarn holding fingers 128a, 128b.

[0441] For this purpose the yarn capturing unit 101 inserts the yarn 8 into receiving recesses 130 on the yarn holding fingers 128a, 128b by moving the robot arm 103 of the yarn capturing unit 101 accordingly. The receiving recesses 130 are arranged at the free end section of the yarn holding fingers 128a, 128b with a recess opening directed to the front end of the yarn holding fingers 128a, 128b.

[0442] The yarn 8 in the receiving recesses 130 is secured and tensioned by securing elements 132 arranged on the yarn holding fingers 128a, 128b so that the yarn cannot escape from the receiving recesses 130.

[0443] For this purpose the securing elements 132 are moveable transverse to the longitudinal axis of the yarn holding fingers 128a, 128b and transverse to the stretch of yarn spanned between the two yarn holding fingers 128a, 128b. The securing elements 132 dislocate the stretch of yarn spanned between the two yarn holding fingers 128a, 128b out of the axis running through the two receiving recesses 130 amid the deflection of the yarn at the receiving recesses 130.

[0444] For guiding the deflected yarn guiding grooves 131 are provided in the yarn holding fingers 128a, 128b which accommodates the deflected yarn. The guiding grooves 131 begin at the receiving recesses 130 and run transverse to the longitudinal axis of the yarn holding fingers 128a, 128b and transverse to the stretch of yarn spanned between the two yarn holding fingers 128a, 128b.

[0445] By deflecting the yarn at the receiving recesses 130 at an acute angle the yarn is securely held in the receiving recesses 130 due to friction, but without being firmly clamped. The dislocation of the stretch of yarn also leads to a tensioning of the stretch of yarn spanned between the two yarn holding fingers 128a, 128b.

[0446] In order to insert yarn into the receiving recesses 130 of the yarn holding fingers 128a, 128b the yarn holding mechanism 127 of the yarn threading unit 121 is positioned such that the two yarn holding fingers 128a, 128b are oriented perpendicular to the course of the yarn spanned between the yarn holding, i.e. clamping mechanism 108 of the yarn capturing unit 101 and the cop package 7. In other words, the axis running through the receiving recesses 130 of the yarn holding fingers 128a, 128b is parallel to the course of the yarn spanned between the yarn holding, i.e. clamping mechanism 108 of the yarn capturing unit 101 and the cop package 7

[0447] For capturing the stretch of yarn 8 by the yarn holding fingers 128a, 128b said course of yarn is in particular oriented perpendicular or essentially perpendicular to the longitudinal direction of the ring rail 5.

[0448] Once the stretch of yarn is spanned and tensioned between the two yarn holding fingers 128a, 128b and secured on the two yarn holding fingers 128a, 128b the yarn holding mechanism 127 with the two yarn holding fingers 128a, 128b is positioned in front of the traveller guiding ring 10 accommodating the traveller 11 such that the stretch of yarn spanned between the two yarn holding fingers 128a, 128b is positioned in parallel to a tangent of the traveller guiding ring 10. The stretch of yarn is in particular positioned parallel to the longitudinal direction of the ring rail 5 (see figure 9).

[0449] Before, after or simultaneously with the positioning of the yarn holding mechanism 127 in front of the traveller guiding ring 10 the cop package 7 is lowered onto the spindle 6 so that the cop package 7 resumes its original spinning position as shown in figure 8. However, the spindle 6 is still in a standstill. For this purpose the grasping mechanism 84 of the cop lifter unit 81 is lowered.

[0450] By positioning the yarn holding fingers 128a, 128b with the stretch of yarn in front of the traveller guiding ring 10 as shown in figure 9 also the traveller positioning mechanism 124 is positioned towards the traveller guiding ring 10. The traveller positioning mechanism 124 comprises two traveller positioning fingers 125 which are positioned left and right of the cop package 7 close to the traveller guiding ring 10. Each traveller positioning finger 125 comprises at least one outlet opening 126 for discharging pressurised air (see also figure 15). The pressurised air is fed to the traveller positioning fingers 125 by means of air supply tubes 133.

[0451] The discharge of pressurised air is such that the traveller 11 is moved driven by the air current to the front side of the traveller guiding ring 10 close to the positioned stretch of yarn.

[0452] The pressurized air for producing air flows in the yarn suction tube 105 or for positioning the traveller 11 as described above is produced centrally on the yarn breakage handling device 31. Hereto, the yarn breakage handling device 31 comprises a compressor 32 for producing pressurised air and a storage cylinder 33 for storing the pressurised air. The pressurised air is led to the suction tube 105 and the traveller positioning fingers 125 via flexible tubes.

[0453] In present case the traveller positioning fingers 125 are arranged on the yarn holding fingers 128a, 128b and extend beyond the end of the yarn holding fingers 128a, 128b. However, the traveller positioning mechanism 124, and in particular the traveller positioning fingers 125, can also be arranged on a separate unit which is moveable separately from the yarn holding mechanism 127.

[0454] Instead of the discharge of pressurised air another mechanism for positioning the traveller 11 can be provided, which e.g. works which magnetic force instead of pressurised air. In this case as well traveller positioning fingers 125 can be applied.

[0455] Once the traveller 11 is positioned in front of the traveller guiding ring 10 the stretch of yarn can be threaded into the traveller 11 by moving the yarn holding mechanism 127 with the yarn holding fingers 128a, 128b accordingly.

[0456] During the positioning of the traveller 11 and the threading of the yarn into the traveller 11 the yarn holding and traveller positioning mechanism 127, 124 of the yarn threading unit 121 has to follow the movement of the ring rail 5 which continues moving up and down.

[0457] For this purpose the yarn holding and traveller positioning mechanism 127, 124 of the yarn threading unit 121 follows the movement of the ring rail 5 based on sensor data of the ring rail sensor 94 which detects the continuously changing height level of the ring rail 5 or the change of said height level itself.

[0458] In present case the level verifying unit 91 also contains a lifting and lowering mechanism 92 which lifts and lowers a carrier 93 synchronous to the movement of the ring rail 5. The yarn holding and traveller positioning mechanism 127, 124 of the yarn threading unit 121 are fastened on the carrier 93 via the corresponding robot arm 103 and are moved up and down synchronously to the movement of the ring rail 5. The lifting and lowering mechanism 92 can be driven pneumatically, hydraulically or by means of electric motors, in particular step motors. The ring rail sensor 94 is an optical position sensor which is directed from above to the ring rail 5.

[0459] However, it can also be envisaged that the sensor data of the ring rail sensor 94 are directly fed to the control unit 34 for controlling the movement of the corresponding robot arm 103. Accordingly, the changing height level of the ring rail 5 is directly considered, i.e. implemented in the movements of the robot arm 103 and accordingly of the yarn holding and traveller positioning mechanism 127, 124 of the yarn threading unit 121.

[0460] It has to be noted that once the yarn end section has been held, i.e. clamped by the yarn holding, i.e. clamping mechanism 108 of the yarn capturing unit 101 the yarn 8 is held by the yarn holding, i.e. clamping mechanism 108 throughout the whole resurrection process until piecing the yarn 8 with the fibre strand of the drafting arrangement 16. This means that during the threading step the yarn is still held by the yarn holding, i.e. clamping mechanism 108 of the yarn capturing unit 101.

[0461] Once the yarn is thread into the traveller 11 the yarn holding mechanism 127 of the yarn threading unit 121 retracts from the traveller guiding ring 10 and releases the yarn as shown in figure 10. For this purpose the yarn holding mechanism 127 of the yarn threading unit 121 is positioned again such that the two yarn holding fingers 128a, 128b are oriented perpendicular to the course of the yarn spanned between the yarn holding, i.e. clamping mechanism 108 of the yarn capturing unit 101 and the cop package 7. In other words, the axis running through the receiving recesses 130 of the yarn holding fingers 128a, 128b is parallel to the course of the yarn spanned between the yarn holding, i.e. clamping mechanism 108 of the yarn capturing unit 101 and the cop package 7.

[0462] After releasing the yarn from the yarn holding mechanism 127 of the yarn threading unit 121 the yarn capturing unit 101 comes into action again as shown in figure 11. The yarn holding, i.e. clamping mechanism 108 of the yarn capturing unit 101 with the held yarn end section is moved towards the balloon control ring 15, if present (not shown in figure 3 to 12). The yarn capturing unit 101 threads the yarn 8 into the balloon control ring 15 (see figure 1).

[0463] Subsequently, the yarn capturing unit 101 with the yarn holding, i.e. clamping mechanism 108 is further moved with the held yarn end section towards the lappet hook 14. The yarn capturing unit 101 threads the yarn 8 into the lappet hook 14 as shown in figure 12.

[0464] In a last step the held yarn end and the fibre strand 19 of the drafting arrangement 16 are pieced together. According to present embodiment the yarn capturing unit 101 places the yarn end section behind the delivery rollers 17, 18, i.e. between the apron arrangement and the delivery rollers 17, 18 of the drafting arrangement 16 as shown in figure 13. During this process step the yarn end section is brought together with the fibre strand 19 of the drafting arrangement 16, in particular with the fibre strand 19 leaving the apron arrangement. As a result the yarn end section 8 and the fibre strand 19 of the drafting arrangement 16 leave together the nip of the delivery rollers 17, 18 and are twisted together due to the resumed spinning process and thus are pieced together.

[0465] However, it is also possible that another piecing procedure is applied, e.g. using an auxiliary yarn. So, the yarn can also be pieced with the drafted fibre strand 19 leaving the delivery rollers 17, 18 in front of the delivery rollers 17, 18 as viewed in process direction.

[0466] During the yarn piecing step being carried out the spindle stopper 64 of the spindle stopper unit 61 releases the spindle brake 12 so that the spindle 6 starts revolving again. Accordingly, the spindle stopper 64 is retracted from the spindle brake 12.

[0467] With the spindle 6 starting revolving again the spinning process is resumed and the pieced yarn is wound on the revolving cop 7.

[0468] The yarn piecing process is now finished and the mechanical units of the yarn breakage handling device 31 can be retracted to their starting position if not already done.

[0469] In a further development of the invention as shown in figure 16 the yarn breakage handling device 31 comprises a roving motion activating unit 151 with an activating mechanism 153. In present case the roving motion activating unit 151 corresponds to a yarn piecing unit and the activating mechanism 153 corresponds to piecing fingers.

[0470] The roving motion activating unit 151 is configured to operate a roving stop motion device 152 for resuming the supply of input roving material 22 automatically to the drafting arrangement 16.

[0471] In present case the roving motion activating unit 151 is configured to switch ON the roving stop motion device 152 thereby resuming the supply of input roving material 22 automatically to the drafting arrangement 16. After resumption of supply of roving 22, the yarn breakage handling device 31 starts its piecing operation as explained further above.

[0472] In present case the roving motion activating unit 151 comprises a moving and positioning mechanism for moving and positioning the activating mechanism 153 and a robot arm 153, in particular an articulated robot arm. In this embodiment the activating mechanism 153 is arranged in a distal end of the robot arm 153. The moving and positioning mechanism is configured for actuating the corresponding robot arm 153.

[0473] As mentioned above the roving motion activating unit 151 also corresponds to a piecing unit for piecing, in particular for piecing at the exit side of the delivery rollers 17, 18. The piecing mechanism comprises two fingers for introducing a twist into the joined fibre strands.

Claims

1. A device (31) for automated resurrection of a yarn breakage in a ring spinning machine (1), the device (31) comprising a robot arrangement (51) for carrying out a plurality of work steps for resurrection of a yarn breakage and a transportation arrangement (141) with a drive (142) for moving the device (31) along the ring spinning machine (1),
wherein the robot arrangement (51) comprises:

- a yarn capturing unit (101) having a yarn attracting and picking mechanism (104) for attracting and picking the yarn end from a cop (7), a yarn holding mechanism (108) for holding the picked yarn, and a moving and positioning mechanism (102) for moving and positioning the yarn attracting and picking mechanism (104), and

- a yarn threading unit (121) for threading the yarn (8) into the traveller (11), having a yarn holding mechanism (127), a traveller positioning mechanism (124) and a moving and positioning mechanism (122) for moving and positioning the yarn holding mechanism (127) and the traveller positioning mechanism (124).

2. The device (31) according to claim 1, characterised in that the yarn capturing unit (101) is designed for permanently holding the yarn starting from picking the yarn end from the cop (7) until piecing the yarn to the fibre strand (19) of the drafting arrangement (16).

3. The device (31) according to claim 1 or 2, characterised in that the yarn capturing unit (101) comprises a yarn suction tube (105) for sucking in the yarn end from the cop (7) through a front opening (106), wherein the yarn suction tube (105) in particular is open on both sides such that a yarn end which is sucked in at the front opening (106) passes through the yarn suction tube (105) and leaves the yarn suction tube (105) through a rear opening (107).

4. The device (31) according to claim 3, characterised in that the yarn suction tube (105) comprises at least one gas inlet for feeding a gas into the yarn suction tube (105) having an inflow component parallel to the tube axis (110).

5. The device (31) according to one of claims 1 to 4, characterised in that the yarn holding mechanism (127) of the yarn threading unit (121) comprises at least two holding fingers (128a, 128b) each holding finger (128a, 128b) having a securing mechanism (132) for securing the yarn on the holding finger (128a, 128b) this for spanning a stretch of yarn between the at least two holding fingers (128a, 128b).

6. The device (31) according to one of claims 1 to 5, characterised in that the traveller positioning mechanism (124) comprises at least two traveller positioning members (125), which are distanced to each other in an operation position such that a first positioning member (125) can be positioned to the right and a second positioning member (125) can be positioned to the left of the cop (7) for positioning the traveller (11), wherein in particular each positioning member (125) has an air passage opening, in particular an outlet opening (126), for producing an air current, in particular for discharging air.

7. The device (31) according to one of claims 1 to 6, characterised in that the robot arrangement (51) comprises a level verifying unit (91) for lifting and lowering the yarn threading unit (121) synchronously with the movement of the ring rail (5) of the ring spinning machine (1), wherein the level verifying unit (91) in particular comprises a ring rail sensor (94) for detecting the movement of the ring rail (5).

8. The device (31) according to claim 7, characterised in that the device (31) comprises at least one optical sensor (35), in particular at least one camera, for collecting navigation information for navigating the device (3 1).

9. The device (31) according to one of the claims 1 to 8, characterised in that the device (31) comprises a malfunction localisation sensor (35), e.g. in the form of an optical sensor (35), in particular of a camera, for detecting at least one of the following detectable conditions:

- a light signal of a signal lamp (3b) of a spinning position monitoring system (3) indicating a yarn breakage;

- the presence or non-presence of a running yarn between the delivery rollers (17, 18) of the drafting arrangement (16) and the cop (7);

- the movement or non-movement of a traveller (11).

10. The device (31) according to one of claims 1 to 9, characterised in that the robot arrangement (51) comprises yarn end detaching means for detaching the yarn end from the surface of the cop (7).

11. The device (31) according to one of claims 1 to 10, characterised in that the robot arrangement (51) comprises a spindle stopper unit (61) for stopping the rotation of the spindle (6) during resurrection of the yarn breakage.

12. The device (31) according to one of claims 1 to 11, characterised in that the robot arrangement (51) comprises a cop lifter unit (81) for lifting the cop (7) from the spindle (6).

13. The device (31) according to one of claims 1 to 12, characterised in that the robot arrangement (51) comprises a lappet hook lifter unit (71) for lifting the lappet hook (14).

14. The device (31) according to one of claims 1 to 13, characterised in that the robot arrangement (51) comprises a roving motion activating unit (151) for operating a roving stop motion device (153).

15. A system comprising a device (31) for automated resurrection of a yarn breakage in a ring spinning machine (1) according to one of the claims 1 to 13, and an individual spinning position monitoring system (3) for detecting yarn breakages.

16. A method for resurrection of a yarn breakage in a ring spinning machine (1) with a device (31) according to one of the claims 1 to 14, comprising the steps of:

- detecting a yarn breakage;

- moving the device (31) in front of the spinning position (4) with the yarn breakage and aligning the device (31) on the spinning position (4);

- stopping the rotation of the spindle (6);

- catching the yarn end from the cop (7);

- threading the yarn (8) through the traveller (11);

- threading the yarn (8) through at least one yarn guiding element (14);

- resuming the rotation of the spindle (6) and

- piecing the yarn (8) together with the fibre strand (19) processed in the drafting arrangement (16).

17. The method according to claim 16, comprising the step of:

- lifting the cop (7) from the spindle (6),

which is carried out between the steps "stopping the rotation of the spindle (6)" and "catching the yarn end from the cop (7)".

18. The method according to one of claims 16 to 17, characterised in that the yarn piecing process comprises one of the steps of:

- moving and positioning the yarn end section, which in particular is held and moved by the yarn capturing unit (101), ahead of the delivery rollers (17, 18) as viewed in process direction (F) and laying the yarn end section over the drafted roving located in the drafting arrangement (16) ahead of the front delivery rollers (17, 18) and let passing the joined textile strands through the delivery rollers (17, 18), or

- moving and positioning the yarn end section subsequent to the delivery rollers (17, 18) of the drafting arrangement (16) as viewed in process direction (F) and laying the yarn end section over the drafted roving leaving the drafting arrangement (16) through the delivery rollers (17, 18) and introducing a twist into the joined textile strands by means of a yarn piecing unit (153).

Drawing