YARN JOINING DEVICE AND YARN WINDING DEVICE

Abstract

 One object is to provide a yarn joining device that can favorably join even elastic yarns. Yarn ends of two yarns (Y1, Y2) held by corresponding clamps (42A, 42B) and cut by corresponding cutters (41A, 41B) are sucked with corresponding untwisting pipes (32A, 32B) each having a suction vent (32a) arranged between a yarn joining nozzle (31) and the cutter (41A, 41B) in an up-down direction. When doing so, the cutters (41A, 41B) are caused to cut the yarns (Y1, Y2) while the yarns (Y1, Y2) are in contact with a yarn shrinkage suppression mechanism (37A, 37B) that can move so as to contact the yarns (Y1, Y2) between the suction vents (32a) and the yarn joining nozzle (31) in the up-down direction.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

[0001] The present invention relates to a yarn joining device and a yarn winding device that includes the yarn joining device.

2. Description of the Related Art

[0002] For example, a yarn joining device is disclosed in Japanese Patent Application Laid-Open No. S59-112038. In this yarn joining device, yarn ends of two yarns are introduced into a yarn joining space formed in a yarn joining nozzle, and then, compressed air is jetted into the yarn joining space to twist the yarn ends together by a swirling air current generated in the yarn joining space and join the yarns. A clamp is arranged on one side of the yarn joining nozzle and a cutter is arranged on the other side. Moreover, a suction vent of an untwisting pipe is arranged between the yarn joining nozzle and the cutter.

[0003] When the yarn gripped by the clamp is cut by the cutter, the yarn ends are sucked into the untwisting pipes and untwisted by the action of an air current present in the untwisting pipes . Thereafter, the untwisted yarn ends are pulled out from the untwisting pipes, and the yarn ends are joined together in the yarn joining space.

[0004] However, the following problem arises when a yarn having elasticity (hereinafter, "elastic yarn"), such as Core Spun Yarn (CSY), is joined by using the yarn joining device disclosed in Japanese Patent Application Laid-Open No. S59-112038. When the elastic yarn gripped by the clamp is cut by the cutter, the yarn shrinks vigorously and disadvantageously passes by the suction vent without being sucked into the untwisting pipes.

SUMMARY OF THE INVENTION

[0005] The present invention has been made in view of the above discussion. One object of the present invention is to provide a yarn joining device that can favorably join even elastic yarns.

[0006] A yarn joining device according to one aspect of the present invention includes a yarn joining nozzle having a yarn joining space extending in a predetermined direction; two clamps each arranged on either side of the yarn joining nozzle in the predetermined direction for gripping a corresponding yarn; two cutters each arranged on either side of the yarn joining nozzle in the predetermined direction for cutting the corresponding yarn; two untwisting pipes each having a suction vent arranged between the yarn joining nozzle and the corresponding cutter in the predetermined direction for sucking a yarn end of the corresponding yarn gripped by the corresponding clamp and cut by the corresponding cutter; a control section; and a yarn shrinkage suppression mechanism capable of moving so as to contact the yarns between the suction vents and the yarn joining nozzle in the predetermined direction. The control section causes the cutters to cut the yarns while the yarn shrinkage suppression mechanism is in contact with the yarns.

[0007] A yarn winding device according to another aspect of the present invention includes a yarn supplying unit that supplies a yarn; a winding unit that is arranged at a position separated from the yarn supplying unit in the predetermined direction and that winds the yarn supplied from the yarn supplying unit; and the above yarn joining device arranged between the yarn supplying unit and the winding unit in the predetermined direction.

[0008] The above and other objects, features, advantages and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] 

FIG. 1 is a schematic configuration diagram of an automatic winder according to one embodiment.

FIG. 2 is a block diagram showing an electrical configuration of the automatic winder according to the present embodiment.

FIG. 3 is a schematic configuration diagram of a winding unit.

FIG. 4A is a front view and FIG. 4B is a side view of a yarn joining device immediately after yarns are guided to the yarn joining device.

FIG. 5 is a perspective view of a structure around an attachment member of yarn shrinkage control levers.

FIG. 6A is a front view and FIG. 6B is a side view of the yarn joining device just before the yarns are cut by cutters.

FIG. 7A is a front view and FIG. 7B is a side view of the yarn joining device immediately after the yarns are cut by the cutters.

FIG. 8A is a front view and FIG. 8B is a side view of the yarn joining device in a state that yarn ends have been introduced into a yarn joining space.

FIG. 9A is a front view and FIG. 9B is a side view of the yarn joining device while the yarn joining device is joining the yarns.

DETAILED DESCRIPTION

[0010] Exemplary embodiments of the present invention will be explained below with reference to the drawings.

Automatic Winder

[0011] FIG. 1 is a schematic configuration diagram of an automatic winder according to one embodiment. FIG. 2 is a block diagram showing an electrical configuration of the automatic winder according to the present embodiment. As shown in FIG. 1, an automatic winder 1 includes a plurality of winding units (corresponding to a yarn winding device according to the present invention) 2 arranged in one direction, and a doffing device 3 capable of moving freely along the direction of arrangement of the winding units 2. In the following description, the left-right direction of FIG. 1, in which the winding units 2 are arranged, is referred to as a "left-right direction". Moreover, the direction vertical to the paper on which FIG. 1 has been printed is referred to as a "front-rear direction" while the side toward the reader is referred to as a "front side" and the side away from the reader is referred to as a "rear side".

[0012] In the automatic winder 1, each winding unit 2 forms a package P by unwinding a yarn Y from a yarn supplying bobbin B and winding the yarn Y on a winding tube. When formation of the package P is completed in a certain winding unit 2, the doffing device 3 moves to a position facing this winding unit 2, and replaces the formed package P with an empty winding tube. As shown in FIG. 2, the automatic winder 1 includes a main controller 4, a plurality of unit controllers 5, and a doffing control device 6. The main controller 4 controls the entire automatic winder 1 and issues control signals to each unit controller 5 and the doffing control device 6. One unit controller 5 is provided separately for each winding unit 2 and controls the operation of each part of the winding unit 2. The doffing control device 6 is arranged corresponding to the doffing device 3 and controls the operation of the doffing device 3.

Winding Unit

[0013] A detailed configuration of the winding unit 2 will be explained below. FIG. 3 is a schematic configuration diagram of the winding unit 2. The winding unit 2 forms the package P by unwinding the yarn Y from the yarn supplying bobbin B and winding the yarn Y around a winding tube Q while traversing the yarn Y. In the present embodiment, the yarn Y is an elastic yarn having elasticity such as a core spun yarn (CSY) . The CSY is a yarn in which short fibers are twisted around a core polyurethane yarn having elasticity.

[0014] As shown in FIG. 3, the winding unit 2 includes a yarn supplying unit 11 that holds a yarn supplying bobbin B such that the yarn Y wound on the yarn supplying bobbin B can be supplied, a yarn processing execution unit 12 that performs various processes on the yarn Y unwound from the yarn supplying bobbin B held by the yarn supplying unit 11, and a winding unit 13 that forms the package P by winding the yarn Y processed by the yarn processing execution unit 12 around the winding tube Q. The yarn supplying unit 11, the yarn processing execution unit 12, and the winding unit 13 are arranged in this order from bottom to top.

[0015] The yarn supplying unit 11 includes a bobbin holding member 15 that holds the yarn supplying bobbin B, and an unwinding assisting device 16 that assists in unwinding the yarn Y from the yarn supplying bobbin B. The unwinding assisting device 16 includes a cylindrical body 29 that caps the yarn supplying bobbin B from above. The cylindrical body 29 can be raised and lowered by a not shown motor. As the unwinding of the yarn Y progresses, the cylindrical body 29 of the unwinding assisting device 16 is lowered. As a result, the bulging (ballooning) of the yarn Y that is being unwound is restricted and the tension of the yarn Y is stabilized.

[0016] The winding unit 13 includes a cradle 14, which rotatably holds the winding tube Q, and a traverse drum 18. The traverse drum 18 is rotationally driven by a not shown drum motor. A spiral traversing groove 18a is formed on an outer peripheral surface of the traverse drum 18. The yarn Y is traversed by using the traversing groove 18a. When the traverse drum 18 rotates in a state that the traverse drum 18 is in contact with the package P formed on the winding tube Q while the yarn Y is traversed by the traversing groove 18a, the package P rotates in a winding direction because of a contact friction with the traverse drum 18. As a result, the yarn Y unwound from the yarn supplying bobbin B is wound on the winding tube Q.

[0017] The yarn processing execution unit 12 located between the yarn supplying unit 11 and the winding unit 13 includes a yarn feeler 19, a tension applying device 20, a yarn joining device 21, and a yarn clearer 22.

[0018] The yarn feeler 19 is arranged between the unwinding assisting device 16 and the tension applying device 20 and detects the presence or absence of the traveling yarn Y.

[0019] The tension applying device 20 applies a predetermined tension to the traveling yarn Y. FIG. 3 shows a so-called gate-type tension applying device 20 as an example. In the gate-type tension applying device 20, a plurality of fixed gate members 20a and a plurality of movable gate members 20b are arranged alternately in the up-down direction. An appropriate tension can be applied to the yarn Y that travels between the fixed gate members 20a and the movable gate members 20b by adjusting the horizontal positions of the movable gate members 20b.

[0020] The yarn joining device 21 is a device that joins the broken yarn Y on the yarn supplying bobbin B side (the yarn supplying unit 11 side) and the broken yarn Y on the package P side (the winding unit 13 side). The yarn Y may be broken when the yarn Y is cut by a cutter 22a when a yarn defect is detected by the yarn clearer 22 described later, when the yarn Y breaks during the winding operation, when the yarn Y on the yarn supplying bobbin B is exhausted so that the empty yarn supplying bobbin B is replaced with another yarn supplying bobbin B, or the like.

[0021] A lower yarn catching guiding member 23 that catches the yarn Y on the yarn supplying bobbin B side and guides the caught yarn Y to the yarn joining device 21 is arranged below the yarn joining device 21. An upper yarn catching guiding member 24 that catches the yarn Y on the package P side and guides the caught yarn Y to the yarn joining device 21 is arranged above the yarn joining device 21. The lower yarn catching guiding member 23 is pivotable around a shaft 23a. The lower yarn catching guiding member 23 is pivoted up or down by a not shown motor. Similarly, the upper yarn catching guiding member 24 is pivotable around a shaft 24a. The upper yarn catching guiding member 24 is pivoted up or down by a not shown motor. The lower yarn catching guiding member 23 and the upper yarn catching guiding member 24 are respectively connected to a not shown suction source.

[0022] The lower yarn catching guiding member 23 has a suction member 23b at its tip end section. The suction member 23b sucks and catches the yarn end of the yarn Y on the yarn supplying unit 11 side. While the suction member 23b has caught the yarn end at a lower position, the lower yarn catching guiding member 23 turns upward and guides the caught yarn Y to the yarn joining device 21.

[0023] The upper yarn catching guiding member 24 has a suction mouth 24b at its tip end section. The suction mouth 24b sucks and catches the yarn end of the yarn Y on the winding unit 13 side. The upper yarn catching guiding member 24 is first turned upward from below, and the suction mouth 24b is positioned near a position where the package P and the traverse drum 18 contact each other. As a result, a yarn end of the yarn Y that has stuck to the surface of the package P can be sucked and caught with the suction mouth 24b. Then, the upper yarn catching guiding member 24 catches the yarn end of the yarn Y and guides the caught yarn Y to the yarn joining device 21 by turning downward from above.

[0024] The yarn joining device 21 joins the yarn end of the yarn Y guided thereto by the lower yarn catching guiding member 23 and the yarn end of the yarn Y guided thereto by the upper yarn catching guiding member 24 to form a continuous yarn Y. The configuration and operation of the yarn joining device 21 will be explained in detail later.

[0025] The yarn clearer 22 continuously acquires information on a thickness of the traveling yarn Y. The yarn clearer 22 detects a yarn defect by using the information on the thickness of the yarn Y. The yarn defect is an abnormal portion in the yarn Y where the thickness is larger than a certain value. The yarn clearer 22 includes the cutter 22a. When the yarn defect is detected by the yarn clearer 22, the cutter 22a immediately cuts the yarn Y.

Yarn Joining Device

[0026] The yarn joining device 21 will be explained in detail below. In the following description, as necessary, the yarn Y on the yarn supplying unit 11 side will be referred to as a yarn Y1 and the yarn Y on the winding unit 13 side will be referred to as a yarn Y2. FIG. 4A is a front view and FIG. 4B is a side view of the yarn joining device 21 immediately after the yarns Y1 and Y2 have been guided to the yarn joining device 21. The yarn joining device 21 includes a support member 30, a yarn joining nozzle 31, two untwisting pipes 32A and 32B, an upper guide plate 33, a lower guide plate 34, two yarn shifting levers 35A and 35B, two twist prevention levers 36A and 36B, two yarn shrinkage control levers 37A and 37B, and the like.

[0027] The yarn joining nozzle 31 is fixed to a front surface of the box-shaped support member 30. The yarn joining nozzle 31 twists the yarn end of the yarn Y1 and the yarn end of the yarn Y2 to join the yarns. The yarn joining nozzle 31 is provided with a yarn joining space 31a extending in the up-down direction (corresponding to a "predetermined direction" according to the present invention). The yarn joining space 31a is open on the front side thereof. The yarns Y1 and Y2 can be introduced into the yarn joining space 31a from the front side of the yarn joining space 31a. Not shown jetting holes for jetting compressed air are formed in an inner wall of the yarn joining space 31a. Then, in a state that the yarn ends of the yarns Y1 and Y2 have been introduced into the yarn joining space 31a, a swirling air current is generated in the yarn joining space 31a by jetting compressed air from the jetting holes to cause the yarn ends of the yarns Y1 and Y2 to be joined.

[0028] The untwisting pipe 32A is arranged above and the untwisting pipe 32B is arranged below the yarn joining nozzle 31. The untwisting pipes 32A and 32B are cylindrical members extending in the front-rear direction, and are embedded in the support member 30. The front and rear ends of the untwisting pipes 32A and 32B are open, and the opening at the front end functions as a suction vent 32a that sucks the yarns Y1 and Y2. The upper untwisting pipe 32A is arranged between the yarn joining nozzle 31 and a cutter 41A described later in the up-down direction. The upper untwisting pipe 32A sucks the yarn Y1 cut by the cutter 41A. On the other hand, the lower untwisting pipe 32B is arranged between the yarn joining nozzle 31 and a later-described cutter 41B in the up-down direction. The lower untwisting pipe 32B sucks the yarn Y2 cut by the cutter 41B.

[0029] Not shown jetting holes for jetting compressed air are formed in the inner walls of the untwisting pipes 32A and 32B. An air current that flows from the front to the rear is generated in the untwisting pipes 32A and 32B by jetting the compressed air from these jetting holes. By the action of this air current, the yarn ends of the yarns Y1 and Y2 can be sucked from the suction vent 32a of each of the untwisting pipes 32A and 32B. Also, by the action of the air current, the yarn ends of the yarns Y1 and Y2 introduced into the untwisting pipes 32A and 32B can be untwisted.

[0030] The upper guide plate 33 is arranged above the yarn joining nozzle 31. The upper guide plate 33 is provided with guide grooves 33a and 33b side by side in the left-right direction. The front ends of the guide grooves 33a and 33b are open. The yarn Y1 is introduced into the left guide groove 33a. A clamp 42A is attached to the upper guide plate 33. The clamp 42A grips the yarn Y2 that has been introduced into the guide groove 33b. In the present invention, when considering the yarn Y2 as a reference, the upper guide plate 33 to which the clamp 42A capable of gripping the yarn Y2 is attached is arranged on one side (corresponding to a "first side" according to the present invention) of the yarn joining space 31a that extends in the up-down direction (corresponding to the predetermined direction according to the present invention). The yarn Y2 is introduced into the right guide groove 33b. The cutter 41A is attached to the upper guide plate 33. The cutter 41A cuts the yarn Y1 that is introduced into the guide groove 33a. In the present invention, when considering the yarn Y1 as a reference, the upper guide plate 33 to which the cutter 41A capable of cutting the yarn Y1 is attached is arranged on another side (corresponding to a "second side" according to the present invention) of the yarn joining space 31a that extends in the up-down direction (corresponding to the predetermined direction according to the present invention).

[0031] The lower guide plate 34 is arranged below the yarn joining nozzle 31. The lower guide plate 34 is provided with guide grooves 34a and 34b side by side in the left-right direction. The front ends of the guide grooves 34a and 34b are open. The yarn Y1 is introduced into the left guide groove 34a. The yarn Y2 is introduced into the right guide groove 34b. The guide grooves 34a and 34b are located substantially directly below the guide grooves 33a and 33b, respectively. A clamp 42B is attached to the lower guide plate 34. The clamp 42B grips the yarn Y1 that has been introduced into the guide groove 34a. In the present invention, when considering the yarn Y1 as a reference, the lower guide plate 34 to which the clamp 42B capable of gripping the yarn Y1 is attached is arranged on the one side (corresponding to the first side according to the present invention) of the yarn joining space 31a that extends in the up-down direction (corresponding to the predetermined direction according to the present invention). The cutter 41B is attached to the lower guide plate 34. The cutter 41B cuts the yarn Y2 that has been introduced into the guide groove 34b. In the present invention, when considering the yarn Y2 as a reference, the lower guide plate 34 to which the cutter 41B capable of cutting the yarn Y2 is attached is arranged on the other side (corresponding to the second side according to the present invention) of the yarn joining space 31a that extends in the up-down direction (corresponding to the predetermined direction according to the present invention) . In summary, the upper guide plate 33 is arranged on the one side in the up-down direction with respect to the yarn Y2, and the lower guide plate 34 is arranged on the other side in the up-down direction. The upper guide plate 33 is arranged on the other side in the up-down direction with respect to the yarn Y1, and the lower guide plate 34 is arranged on the one side in the up-down direction.

[0032] The yarn shifting lever 35A is arranged above the yarn joining nozzle 31 and the yarn shifting lever 35B is arranged below the yarn joining nozzle 31. The upper yarn shifting lever 35A is arranged between the upper untwisting pipe 32A and the upper guide plate 33 in the up-down direction. On the other hand, the lower yarn shifting lever 35B is arranged between the lower untwisting pipe 32B and the lower guide plate 34 in the up-down direction. The yarn shifting levers 35A and 35B are arranged on the right side of the yarn joining nozzle 31. The yarn shifting levers 35A and 35B pivot integrally around a shaft 43 (corresponding to a second pivot shaft according to the present invention) that extends in the up-down direction. When the yarn shifting levers 35A and 35B are pivoted rearward, the yarns Y1 and Y2 are moved (shifted) rearward by the yarn shifting levers 35A and 35B.

[0033] The twist prevention lever 36A is arranged above the yarn joining nozzle 31 and the twist prevention lever 36B is arranged below the yarn joining nozzle 31. The upper twist prevention lever 36A is arranged between the upper untwisting pipe 32A and the upper yarn shifting lever 35A in the up-down direction. On the other hand, the lower twist prevention lever 36B is arranged between the lower untwisting pipe 32B and the lower yarn shifting lever 35B in the up-down direction. The twist prevention levers 36A and 36B pivot integrally around the shaft 43. When applying the twists to the yarn ends of the yarns Y1 and Y2 in the yarn joining space 31a, the twist prevention lever 36A is in contact with the yarn Y2 and the twist prevention lever 36B is in contact with the yarn Y1. This prevents the twists applied to the yarn ends of the yarns Y1 and Y2 from propagating beyond the twist prevention levers 36A and 36B.

[0034] The yarn shifting levers 35A and 35B and the twist prevention levers 36A and 36B are pivoted around the shaft 43 by a not shown common driving device. However, a not shown stopper restricts the pivoting of the twist prevention levers 36A and 36B. Thus, the twist prevention levers 36A and 36B do not pivot out of a predetermined range. That is, when the yarn shifting levers 35A and 35B and the twist prevention levers 36A and 36B are pivoted by the common driving device, the yarn shifting levers 35A and 35B and the twist prevention levers 36A and 36B pivot together in a certain range, and when the predetermined range is reached, thereafter only the yarn shifting levers 35A and 35B pivot.

[0035]  The yarn shrinkage control lever 37A is arranged above the yarn joining nozzle 31 and the yarn shrinkage control lever 37B is arranged below the yarn joining nozzle 31. The upper yarn shrinkage control lever 37A is arranged between the yarn joining nozzle 31 and the upper untwisting pipe 32A in the up-down direction. On the other hand, the lower yarn shrinkage control lever 37B is arranged between the yarn joining nozzle 31 and the lower untwisting pipe 32B in the up-down direction. The yarn shrinkage control levers 37A and 37B are arranged on the left side of the yarn joining nozzle 31. The yarn shrinkage control levers 37A and 37B pivot integrally around a shaft 44 (corresponding to a first pivot shaft according to the present invention) that extends in the up-down direction. When the yarn shrinkage control levers 37A and 37B are pivoted rearward until they contact the front surface of the support member 30, the yarns Y1 and Y2 are gripped between the yarn shrinkage control levers 37A and 37B and the support member 30. That is, the yarn shrinkage control levers 37A and 37B correspond to a yarn shrinkage suppression mechanism according to the present invention. As long as the yarns Y1 and Y2 can be gripped and the untwisting pipes 32A and 32B are not hindered from sucking the yarn ends of the yarns Y1 and Y2, the position of the yarn shrinkage control levers 37A and 37B in the up-down direction when seen from the front side can overlap with the position of the untwisting pipes 32A and 32B.

Yarn Shrinkage Control Lever

[0036] The yarn shrinkage control levers 37A and 37B will be explained in detail below. FIG. 5 is a perspective view of a structure around an attachment member of the yarn shrinkage control levers 37A and 37B. The yarn shrinkage control levers 37A and 37B are integrally formed via a cylindrical boss 38 that extends in the up-down direction. That is, the yarn shrinkage control lever 37A is fixed to an upper end of the boss 38 and the yarn shrinkage control lever 37B is fixed to a lower end of the boss 38. The boss 38 is attached to the shaft 44 via a not shown bearing. The shaft 44 is fixed to a base member 45. The base member 45 is fixed to the support member 30 of the yarn joining device 21. With such a configuration, the yarn shrinkage control levers 37A and 37B can pivot integrally around the shaft 44.

[0037] A torsion spring 46 (corresponding to a biasing member according to the present invention) is arranged in a portion of the shaft 44 between the lower yarn shrinkage control lever 37B and the base member 45. A not shown lower end of the torsion spring 46 is fixed to the base member 45, and an upper end 46a of the torsion spring 46 is fixed to the yarn shrinkage control lever 37B. The torsion spring 46 biases the yarn shrinkage control levers 37A and 37B toward the front surface of the support member 30 (the direction of an arrow F in FIG. 5) (hereinafter, "biasing direction F"). A plurality of attachment holes 37a for inserting the upper end 46a of the torsion spring 46 are formed in the yarn shrinkage control lever 37B in the circumferential direction of the shaft 44. The biasing force by the torsion spring 46 can be adjusted by inserting the upper end 46a of the torsion spring 46 in a desired one of the attachment holes 37a. That is, these attachment holes 37a correspond to an adjustment member according to the present invention.

[0038] A rotary member 47 capable of rotating around a central axis of the shaft 44 is arranged below the base member 45. The rotary member 47 has the shape of English letter L when viewed from the up-down direction. The rotary member 47 has a first arm 47a and a second arm 47b that are substantially perpendicular to each other. A regulating pin 48 (corresponding to a regulating member according to the present invention) that extends upward is fixed to the first arm 47a. A cylinder 49 is connected to the second arm 47b. An upper end of the regulating pin 48 is passed through a through hole 37b formed in the yarn shrinkage control lever 37B. As a result, the regulating pin 48 can revolve around the shaft 44 while restricting the yarn shrinkage control lever 37B from moving in the biasing direction F. The through hole 37b has a larger diameter than that of the regulating pin 48. Accordingly, the yarn shrinkage control lever 37B and the regulating pin 48 can relatively move together in the biasing direction F.

[0039] When the yarn joining device 21 is not performing the yarn joining, the yarn shrinkage control levers 37A and 37B are biased in the biasing direction F by the torsion spring 46; however, the movement in the biasing direction F of the yarn shrinkage control levers 37A and 37B is regulated by the regulating pin 48. To operate the yarn shrinkage control levers 37A and 37B, the rotary member 47 is rotated by the cylinder 49 in the same direction as the biasing direction F. Then, the regulating pin 48 revolves in the same direction as the biasing direction F, and the yarn shrinkage control levers 37A and 37B also pivot in the biasing direction F together with the regulating pin 48. The cylinder 49 stops the rotation of the rotary member 47 at the timing when the yarn shrinkage control levers 37A and 37B contact the front surface of the support member 30. The yarn shrinkage control levers 37A and 37B press the yarns Y1 and Y2 against the front surface of the support member 30. As a result, the yarns Y1 and Y2 are gripped by being sandwiched between the yarn shrinkage control levers 37A and 37B and the support member 30.

Yarn Joining Operation

[0040] The yarn joining operation when the yarns Y1 and Y2 are joined by the yarn joining device 21 will be explained in detail below with reference to FIG. 6A to FIG. 9B. FIG. 6A is a front view and FIG. 6B is a side view of the yarn joining device 21 just before the yarns Y1 and Y2 are cut by the cutters 41A and 41B. FIG. 7A is a front view and FIG. 7B is a side view of the yarn joining device 21 immediately after the yarns Y1 and Y2 are cut by the cutters 41A and 41B. FIG. 8A is a front view and FIG. 8B is a side view of the yarn joining device 21 in a state that the yarn ends of the yarns Y1 and Y2 have been introduced into the yarn joining space 31a. FIG. 9A is a front view and FIG. 9B is a side view of the yarn joining device 21 while the yarn joining device 21 is joining the yarns.

[0041] When the yarn Y is broken for some reason, first, as shown in FIGS. 4A and 4B, the yarns Y1 and Y2 are guided to the yarn joining device 21 by the lower yarn catching guiding member 23 and the upper yarn catching guiding member 24. At this time, the yarn Y1 is introduced also into the guide grooves 33a and 34a, and the yarn Y2 is introduced also into the guide grooves 33b and 34b.

[0042] In this state, the unit controller 5 (corresponding to a control section according to the present invention) causes the yarns Y1 and Y2 to be moved rearward by pivoting the yarn shifting levers 35A and 35B rearward. As a result, as shown in FIGS. 6A and 6B, the yarns Y1 and Y2 are introduced into the yarn joining space 31a of the yarn joining nozzle 31. Moreover, the yarn Y1 is pushed into the interior of the guide grooves 33a and 34a and gripped by the clamp 42B, and the yarn Y2 is pushed into the interior of the guide grooves 33b and 34b and gripped by the clamp 42A.

[0043] The unit controller 5 pivots the yarn shrinkage control levers 37A and 37B rearward at the same time or immediately after causing the yarn shifting levers 35A and 35B to pivot rearward. Then, as shown in FIGS. 6A and 6B, the yarn shrinkage control lever 37A contacts the front surface of the support member 30 between the yarn joining nozzle 31 and the untwisting pipe 32A. As a result, the yarn Y1 is sandwiched between the yarn shrinkage control lever 37A and the support member 30 whereby the yarn Y1 is gripped. Also, the yarn shrinkage control lever 37B contacts the front surface of the support member 30 between the yarn joining nozzle 31 and the untwisting pipe 32B. As a result, the yarn Y2 is sandwiched between the yarn shrinkage control lever 37B and the support member 30 whereby the yarn Y2 is gripped. The force with which the yarn shrinkage control levers 37A and 37B grip the yarns Y1 and Y2 is such that when the yarn ends of the yarns Y1 and Y2 are pulled out from the untwisting pipes 32A and 32B in the subsequent process, the yarn ends slip through between the yarn shrinkage control levers 37A and 37B and the support member 30.

[0044] Next, the unit controller 5 causes the cutter 41A to cut the yarn Y1 and causes the cutter 41B to cut the yarn Y2. At the same time or just before cutting the yarns Y1 and Y2, an air current is generated in the untwisting pipes 32A and 32B from the front to the rear. Accordingly, as shown in FIGS. 7A and 7B, the cut yarn end of the yarn Y1 is sucked into the upper untwisting pipe 32A, and the cut yarn end of the yarn Y2 is sucked into the lower untwisting pipe 32B. The yarn ends of the yarns Y1 and Y2 are untwisted by the air current generated in the untwisting pipes 32A and 32B. The unnecessary portions of the cut yarns Y1 and Y2 are sucked by the lower yarn catching guiding member 23 and the upper yarn catching guiding member 24.

[0045] Since the yarn Y is the elastic yarn, such as CSY, when the yarn Y is cut by the cutters 41A and 41B into the yarns Y1 and Y2 respectively, the yarns Y1 and Y2 shrink vigorously whereby the yarns Y1 and Y2 may not be sucked by the untwisting pipes 32A and 32B. However, since the yarns Y1 and Y2 have been gripped by the yarn shrinkage control levers 37A and 37B, the shrinkage of the yarns Y1 and Y2 is stopped near the suction vent 32a by the yarn shrinkage control levers 37A and 37B. Therefore, the yarn ends of the yarns Y1 and Y2 can be reliably sucked by the untwisting pipes 32A and 32B.

[0046] Subsequently, the unit controller 5 pivots the yarn shifting levers 35A and 35B further rearward. Then, as shown in FIGS. 8A and 8B, the untwisted yarn ends of the yarns Y1 and Y2 are pulled out from the untwisting pipes 32A and 32B and introduced into the yarn joining space 31a of the yarn joining nozzle 31. That is, the yarn shifting levers 35A and 35B correspond to pulling members according to the present invention. At this moment, the yarn shrinkage control levers 37A and 37B are gripping the yarns Y1 and Y2 (while pressing the yarns against the support member 30). However, as mentioned above, when the yarn ends of the yarns Y1 and Y2 are pulled out from the untwisting pipes 32A and 32B by the yarn shifting levers 35A and 35B, the gripping force with which the yarns Y1 and Y2 have been gripped is such that the yarn ends slip through between the yarn shrinkage control levers 37A and 37B and the support member 30. Therefore, the yarn ends of the yarns Y1 and Y2 are introduced into the yarn joining space 31a without any problem.

[0047] The unit controller 5 returns the yarn shrinkage control levers 37A and 37B to their respective initial positions almost simultaneously (this timing may be slightly changed) with the jetting of the compressed air into the yarn joining space 31a. By doing so, the yarn ends of the yarns Y1 and Y2 are joined together by the action of the swirling air current present in the yarn joining space 31a. At this time, the twist prevention lever 36A contacts the yarn Y2 and the twist prevention lever 36B contacts the yarn Y1. Accordingly, it is possible to prevent the twists of the yarns from being propagated over the twist prevention levers 36A and 36B at the time of yarn joining. When the yarn joining is completed, the yarn shifting levers 35A and 35B and the twist prevention levers 36A and 36B are returned to their respective initial positions, and the winding of the yarn Y by the winding unit 13 is resumed.

Advantageous Effects

[0048] The yarn joining device 21 of the present embodiment includes the yarn shrinkage suppression mechanism (the yarn shrinkage control levers 37A and 37B) that can operate in a predetermined direction (up-down direction) so as to contact the yarns Y1 and Y2 between the suction vent 32a of the untwisting pipes 32A and 32B and the yarn joining nozzle 31, and the control section (the unit controller 5) causes the cutters 41A and 41B to cut the yarns Y1 and Y2 while the yarns Y1 and Y2 are in contact with the yarn shrinkage control levers 37A and 37B. Therefore, even if the yarns Y1 and Y2 are elastic yarns that shrink vigorously when cut with the cutters 41A and 41B, because the yarn shrinkage control levers 37A and 37B grip the yarns Y1 and Y2 between the suction vent 32a of the untwisting pipes 32A and 32B and the yarn joining nozzle 31, the shrinkage of the yarns Y1 and Y2 is stopped by the yarn shrinkage control levers 37A and 37B. Therefore, even the yarn ends of the elastic yarns Y1 and Y2 can be easily sucked by the untwisting pipes 32A and 32B, and the yarns Y1 and Y2 can be favorably joined.

[0049] In the present embodiment, the yarn shrinkage control levers 37A and 37B grip the yarns Y1 and Y2. If the yarn shrinkage control levers 37A and 37B are configured to grip the yarns Y1 and Y2, the yarn shrinkage control levers 37A and 37B can reliably stop the shrinkage of the yarns Y1 and Y2, and the success rate of joining of the elastic yarns can be increased.

[0050] The present embodiment includes the pulling member (the yarn shifting levers 35A and 35B) for pulling the yarn ends of the yarns Y1 and Y2 sucked by the untwisting pipes 32A and 32B from the untwisting pipes 32A and 32B, and when the yarn ends of the yarns Y1 and Y2 are pulled out from the untwisting pipes 32A and 32B by the pulling members 35A and 35B, the control section 5 causes the yarn shrinkage control levers 37A and 37B to grip the yarns Y1 and Y2. When joining the elastic yarns Y, shrinkage occurs not only when the yarns Y1 and Y2 are cut by the cutters 41A and 41B, but also when the yarn ends of the yarns Y1 and Y2 are pulled out from the untwisting pipes 32A and 32B. When shrinkage occurs, there is a possibility that the yarn ends of the yarns Y1 and Y2 are not positioned at the predetermined positions in the yarn joining space 31a, leading to failure in the yarn joining. Therefore, as mentioned above, by griping the yarns Y1 and Y2 with the yarn shrinkage control levers 37A and 37B at the time of pulling out the yarn ends of the yarns Y1 and Y2 from the untwisting pipes 32A and 32B, shrinkage of the yarns Y1 and Y2 can be stopped by the yarn shrinkage control levers 37A and 37B. As a result, the yarn ends of the yarns Y1 and Y2 can be surely positioned at the predetermined positions in the yarn joining space 31a, and the yarn joining can be performed favorably.

[0051] In the present embodiment, the yarn shrinkage control levers 37A and 37B grip the yarns Y1 and Y2 with a force of such a magnitude that allows the yarn ends of the yarns Y1 and Y2 pulled out by the pulling members 35A and 35B from the untwisting pipes 32A and 32B to slip through the yarn shrinkage control levers 37A and 37B. As mentioned above, when the yarn ends of the yarns Y1 and Y2 are pulled out from the untwisting pipes 32A and 32B, favorable joining is achieved if the yarn shrinkage control levers 37A and 37B grip the yarns Y1 and Y2. However, if the yarn shrinkage control levers 37A and 37B grip the yarns Y1 and Y2 strongly, the yarn ends of the yarns Y1 and Y2 cannot be pulled out from the untwisting pipes 32A and 32B in the first place. Accordingly, when the yarn ends are pulled out from the untwisting pipes 32A and 32B, a delicate control needs to be performed to weaken the gripping force of the yarn shrinkage control levers 37A and 37B. In this respect, when the gripping force with which the yarns Y1 and Y2 are gripped by the yarn shrinkage control levers 37A and 37B is such that the yarn ends of the yarns Y1 and Y2 pulled out from the untwisting pipes 32A and 32B can slip through the yarn shrinkage control levers 37A and 37B, the delicate control of the yarn shrinkage control levers 37A and 37B becomes unnecessary. Therefore, this structure is preferable.

[0052] In the present embodiment, the yarns Y1 and Y2 are sandwiched between the yarn shrinkage control levers 37A and 37B and the support member 30 that supports the yarn joining nozzle 31 thereby gripping the yarns Y1 and Y2. By adopting such a configuration, the configuration of the yarn shrinkage control levers 37A and 37B can be simplified.

[0053] In the present embodiment, the yarn shrinkage suppression mechanism is realized by the yarn shrinkage control levers 37A and 37B that can pivot around a first pivot shaft (the shaft 44) that extends in a predetermined direction. By adopting such a configuration, the yarn shrinkage suppression mechanism can be easily realized even in the yarn joining device 21 in which not much empty space is available.

[0054] The present embodiment includes the biasing member (the torsion spring 46) that biases the yarn shrinkage control levers 37A and 37B toward the support member 30. By adopting such a biasing member 46, the yarns Y1 and Y2 can be sandwiched between the yarn shrinkage control levers 37A and 37B and the support member 30 and can be securely gripped therebetween.

[0055] The present embodiment includes the regulating member (the regulating pin 48) that can revolve around the first pivot shaft 44 while restricting the movement of the yarn shrinkage control levers 37A and 37B in the biasing direction F of the biasing member 46, and the yarn shrinkage control levers 37A and 37B and the regulating member 48 are relatively movable in the biasing direction F. In this configuration, by rotating the regulating member 48 to the support member 30 side, the yarn shrinkage control levers 37A and 37B, whose movement in the biasing direction F is regulated by the regulating member 48, can be moved to the biasing direction (the support member side) . Also, because the yarn shrinkage control levers 37A and 37B and the regulating member 48 can move relatively in the biasing direction F, when the yarn shrinkage control levers 37A and 37B abut against the support member 30 and can no longer move in the biasing direction F, only the regulating member 48 moves to the biasing direction F. Therefore, even if there is an error in the rotation control of the regulating member 48, the yarn shrinkage control levers 37A and 37B can be controlled to prevent from being strongly pressed against the support member 30 by the regulating member 48, and a control by using the yarn shrinkage control levers 37A and 37B of the biasing force for gripping the yarns Y1 and Y2 to a certain value becomes easy.

[0056] The present embodiment includes the adjustment member (the attachment holes 37a) for adjusting the biasing force exerted by the biasing member 46. By adopting such an adjustment member, for example, the gripping force for gripping the yarns Y1 and Y2 can be adjusted according to the elasticity of the yarn Y.

[0057] The present embodiment includes the yarn shifting levers 35A and 35B that can pivot around the second pivot shaft (the shaft 43) extending in a predetermined direction to introduce the yarns Y1 and Y2 into the yarn joining space 31a, and the first pivot shaft 44 of the yarn shrinkage control levers 37A and 37B and the second pivot shaft 43 of the yarn shifting levers 35A and 35B are arranged on opposite sides with respect to the yarn joining nozzle 31. With such an arrangement, a driving device such as the cylinder 49 for driving the yarn shrinkage control levers 37A and 37B can be easily arranged.

Other Embodiments

[0058] Other embodiments that are the modifications of the above embodiment are explained below.

[0059] In the above embodiment, when the yarn ends of the yarns Y1 and Y2 are pulled out from the untwisting pipes 32A and 32B by the yarn shifting levers 35A and 35B, the yarns Y1 and Y2 are held by the yarn shrinkage control levers 37A and 37B. However, when the elasticity of the elastic yarn Y is not so high, the shrinkage of the yarns Y1 and Y2 when the yarn ends are pulled out from the untwisting pipes 32A and 32B may not be a problem. In this case, the gripped state of the yarns Y1 and Y2 by the yarn shrinkage control levers 37A and 37B can be released before the yarn ends are pulled out from the untwisting pipes 32A and 32B. By adopting such a configuration, when pulling out the yarn ends of the yarns Y1 and Y2 from the untwisting pipes 32A and 32B, there is no need for delicate adjustment and control so that the yarn ends can slip through the yarn shrinkage control levers 37A and 37B.

[0060] In the above embodiment, the gripping force with which the yarn shrinkage control levers 37A and 37B grip the yarns Y1 and Y2 can be maintained to a certain force by which the yarn ends that are pulled out from the untwisting pipes 32A and 32B by the yarn shifting levers 35A and 35B slip through the yarn shrinkage control levers 37A and 37B. However, it is allowable to perform a control such that the yarn shrinkage control levers 37A and 37B grip the yarns Y1 and Y2 firmly when cutting the yarns Y1 and Y2 with the cutters 41A and 41B, and the yarn shrinkage control levers 37A and 37B grip the yarns Y1 and Y2 weakly when pulling out the yarn ends of the yarns Y1 and Y2 from the untwisting pipes 32A and 32B.

[0061] In the above embodiment, the yarn shrinkage control levers 37A and 37B function as the yarn shrinkage suppression mechanism according to the present invention. However, specific examples of the yarn shrinkage suppression mechanism are not limited to the yarn shrinkage control levers 37A and 37B. For example, the technology disclosed in Japanese Patent Application Laid-Open No. 2005-112550 can be used. Specifically, a movable cover mechanism (a shielding mechanism 61) that covers the yarn joining nozzle can be provided, and a gripping member that grips the yarns Y1 and Y2 between itself and the support member 30 can be arranged in the cover mechanism. Also, the yarn shrinkage suppression mechanism is not limited to the one that grips the yarns Y1 and Y2 by sandwiching between itself and the support member 30 but can be a clamp that itself can grip the yarns Y1 and Y2.

[0062] The above embodiment includes the torsion spring 46 for biasing the yarn shrinkage control levers 37A and 37B and the regulating pin 48 for regulating the movement of the yarn shrinkage control levers 37A and 37B to the biasing direction F; however, the torsion spring 46 and the regulating pin 48 can be omitted. Further, in order to adjust the biasing force of the torsion spring 46, a plurality of the attachment holes 37a is provided as the adjustment member of the present invention; however, it is allowable to provide only one attachment hole 37a.

[0063] In the above embodiment, the shaft 43 that is the second pivot shaft for the yarn shifting levers 35A and 35B and the twist prevention levers 36A and 36B, and the shaft 44 that is the first pivot shaft for the yarn shrinkage control levers 37A and 37B are arranged on opposite sides with respect to the yarn joining nozzle 31. However, the second pivot shaft can be used in common by the yarn shifting levers 35A and 35B, the twist prevention levers 36A and 36B, and the yarn shrinkage control levers 37A and 37B. In such a configuration, appropriate stoppers and the like can be provided to cause each of those levers to be driven with a common driving device as desired.

[0064] The above embodiment includes the twist prevention levers 36A and 36B separately from the yarn shrinkage control levers 37A and 37B. However, the yarn shrinkage control levers 37A and 37B can also be configured as the twist prevention levers.

[0065] In the above embodiment, the yarn shrinkage control levers 37A and 37B prevent the yarns Y1 and Y2 from shrinking by gripping the yarns Y1 and Y2 so that the yarn ends of even the elastic yarns can be easily sucked by the untwisting pipes 32A and 32B and favorably joined. However, a rubber member can be attached to the distal ends of the yarn shrinkage control levers 37A and 37B, or the distal ends of the yarn shrinkage control levers 37A and 37B can be made uneven thereby increasing the friction property thereof. When the distal ends have high friction property, the shrinking of the yarns Y1 and Y2 can be suppressed by touching the yarns Y1 and Y2 with the distal ends of the yarn shrinkage control levers 37A and 37B instead of gripping the yarns Y1 and Y2 with the yarn shrinkage control levers 37A and 37B. Accordingly, even the yarn ends of the elastic yarn can be easily sucked with the untwisting pipes 32A and 32B, and it is possible to perform the yarn joining favorably.

[0066] In the above embodiment, the present invention was applied to the yarn joining device 21 provided in the winding unit 2 of the automatic winder 1. However, it is possible to apply the present invention to a yarn joining device of other textile machines (for example, a pneumatic spinning frame).

[0067] In the above embodiment, the predetermined direction is described as the up-down direction; however, the predetermined direction is not limited to the up-down direction. Specifically, the predetermined direction is the direction in which the yarn joining space of the yarn joining nozzle 31 extends, and the direction is generally the direction perpendicular to a surface on which the winding unit is installed; however, this direction can be inclined with respect to the direction perpendicular to the surface on which the winding unit is installed. The inclination angle can be changed (set) as desired by the layout of the yarn joining nozzle 31, the clamps 42A and 42B, the upper yarn catching guiding member 24, and the lower yarn catching guiding member 23.

[0068] A yarn joining device according to one aspect of the present invention includes a yarn joining nozzle having a yarn joining space extending in a predetermined direction; two clamps each arranged on either side of the yarn joining nozzle in the predetermined direction for gripping a corresponding yarn; two cutters each arranged on either side of the yarn joining nozzle in the predetermined direction for cutting the corresponding yarn; two untwisting pipes each having a suction vent arranged between the yarn joining nozzle and the corresponding cutter in the predetermined direction for sucking a yarn end of the corresponding yarn gripped by the corresponding clamp and cut by the corresponding cutter; a control section; and a yarn shrinkage suppression mechanism capable of moving so as to contact the yarns between the suction vents and the yarn joining nozzle in the predetermined direction. The control section causes the cutters to cut the yarns while the yarn shrinkage suppression mechanism is in contact with the yarns.

[0069] According to the above yarn joining device, even if the elastic yarn shrinks vigorously when cut with the cutter, because the yarn shrinkage suppression mechanism contacts the yarns between the suction vents of the untwisting pipes and the yarn joining nozzle, the shrinkage of the yarns is stopped by the yarn shrinkage suppression mechanism. Therefore, even the yarn ends of the elastic yarns can be easily sucked by the untwisting pipes, and the yarns can be favorably joined.

[0070] In the above yarn joining device, it is preferable that the yarn shrinkage suppression mechanism grips the yarns.

[0071] Because the yarn shrinkage suppression mechanism is configured to grip the yarns, the yarn shrinkage suppression mechanism can reliably stop the shrinkage of the yarns, and the success rate of joining of the elastic yarns is increased.

[0072] It is preferable that the above yarn joining device further includes a pulling member that pulls out from the untwisting pipes the yarn ends sucked into the untwisting pipes, and the control section causes the yarn shrinkage suppression mechanism to grip the yarns while the yarn ends are pulled out from the untwisting pipes by the pulling member.

[0073] When joining the elastic yarns, shrinkage occurs not only when the yarns are cut by the cutters, but also when the yarn ends of the yarns are pulled out from the untwisting pipes . When shrinkage occurs, there is a possibility that the yarn ends of the yarns are not positioned at the predetermined positions in the yarn joining space, leading to failure in the yarn joining. Therefore, as mentioned above, by griping the yarns with the yarn shrinkage suppression mechanism at the time of pulling out the yarn ends of the yarns from the untwisting pipes, shrinkage of the yarns can be stopped by the yarn shrinkage suppression mechanism. As a result, the yarn ends of the yarns can be surely positioned at the predetermined position in the yarn joining space, and the yarn joining can be performed favorably.

[0074] In the above yarn joining device, it is preferable that the yarn shrinkage suppression mechanism grips the yarns with such a force that the yarn ends pulled out from the untwisting pipes by the pulling member slip through the yarn shrinkage suppression mechanism.

[0075] As mentioned above, when the yarn ends of the yarns are pulled out from the untwisting pipes, favorable joining is achieved if the yarn shrinkage suppression mechanism grips the yarns. However, if the yarn shrinkage suppression mechanism grips the yarns strongly, the yarn ends of the yarns cannot be pulled out from the untwisting pipes in the first place. Accordingly, when the yarn ends are pulled out from the untwisting pipes, a delicate control needs to be performed to weaken the gripping force of the yarn shrinkage suppression mechanism. In this respect, when the gripping force with which the yarns are gripped by the yarn shrinkage suppression mechanism is such that the yarn ends of the yarns pulled out from the untwisting pipes can slip through the yarn shrinkage suppression mechanism, the delicate control of the yarn shrinkage suppression mechanism becomes unnecessary, and this structure is preferable.

[0076] It is preferable that the above yarn joining device further includes a pulling member that pulls out from the untwisting pipes the yarn ends sucked into the untwisting pipes, and the control section causes the yarn shrinkage suppression mechanism to release the grip on the yarns before causing the pulling member to pull out the yarn ends from the untwisting pipes.

[0077] When the elasticity of the elastic yarn is not so high, the shrinkage of the yarn when the yarn end is pulled out from the untwisting pipe may not be a problem. In this case, the gripped state of the yarn can be released before the yarn end is pulled out from the untwisting pipe. By adopting such a configuration, because there is no need for delicate adjustment and control so that the yarn end can slip through the yarn shrinkage suppression mechanism, this structure is preferable.

[0078] In the above yarn joining device, it is preferable that the yarn shrinkage suppression mechanism grips the yarns by sandwiching the yarns between itself and a support member that supports the yarn joining nozzle.

[0079] By adopting such a configuration, the configuration of the yarn shrinkage suppression mechanism can be simplified.

[0080] In the above yarn joining device, it is preferable that the yarn shrinkage suppression mechanism includes two yarn shrinkage control levers that can pivot around a first pivot shaft that extends in the predetermined direction.

[0081] By adopting such a configuration, the yarn shrinkage suppression mechanism can be easily realized even in the yarn joining device in which not much empty space is available.

[0082] It is preferable that the above yarn joining device further includes a biasing member that biases the yarn shrinkage control levers toward the support member.

[0083]  By adopting such a biasing member, the yarn can be sandwiched between the yarn shrinkage control lever and the support member and can be securely gripped therebetween.

[0084] It is preferable that the above yarn joining device further includes a regulating member capable of rotating around the first pivot shaft while regulating a movement of the yarn shrinkage control levers in a biasing direction of the biasing member, and the yarn shrinkage control levers and the regulating member are relatively movable in the biasing direction.

[0085] In this configuration, by rotating the regulating member to the support member side, the yarn shrinkage control levers, whose movement in the biasing direction is regulated by the regulating member, can be moved to the biasing direction (the support member side). Also, because the yarn shrinkage control levers and the regulating member can move relatively in the biasing direction, when the yarn shrinkage control levers abut against the support member and can no longer move in the biasing direction, only the regulating member moves to the biasing direction. Therefore, even if there is an error in the rotation control of the regulating member, the yarn shrinkage control levers can be controlled to prevent from being strongly pressed against the support member by the regulating member, and a control by using the yarn shrinkage control levers of the biasing force for gripping the yarns to a certain value becomes easy.

[0086] It is preferable that the above yarn joining device further includes an adjustment member capable of adjusting a biasing force of the biasing member.

[0087] By adopting such an adjustment member, for example, the gripping force for gripping the yarn can be adjusted according to the elasticity of the yarn.

[0088] It is preferable that the above yarn joining device further includes two yarn shifting levers each capable of pivoting around a second pivot shaft that extends in the predetermined direction and that introduce the yarns into the yarn joining space, and the first pivot shaft of the yarn shrinkage control levers and the second pivot shaft of the yarn shifting levers are arranged on opposite sides with respect to the yarn joining nozzle.

[0089] With such an arrangement, a driving device such as a cylinder for driving the yarn shrinkage control lever can be easily arranged.

[0090] A yarn winding device according to another aspect of the present invention includes a yarn supplying unit that supplies a yarn; a winding unit that is arranged at a position separated from the yarn supplying unit in the predetermined direction and that winds the yarn supplied from the yarn supplying unit; and the above yarn joining device arranged between the yarn supplying unit and the winding unit in the predetermined direction.

[0091] According to the above yarn winding device, even when winding the elastic yarn, because the yarn end of the yarn cut by the cutter when performing yarn joining can be easily sucked with the untwisting pipe, it is possible to perform the yarn joining favorably.

[0092] In the above explanation, the meaning of "a plurality of" also includes "a predetermined number of".

[0093] Although the invention has been explained with respect to specific embodiments for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art that fairly fall within the scope of the claims. One object is to provide a yarn joining device that can favorably join even elastic yarns. Yarn ends of two yarns (Y1, Y2) held by corresponding clamps (42A, 42B) and cut by corresponding cutters (41A, 41B) are sucked with corresponding untwisting pipes (32A, 32B) each having a suction vent (32a) arranged between a yarn joining nozzle (31) and the cutter (41A, 41B) in an up-down direction. When doing so, the cutters (41A, 41B) are caused to cut the yarns (Y1, Y2) while the yarns (Y1, Y2) are in contact with a yarn shrinkage suppression mechanism (37A, 37B) that can move so as to contact the yarns (Y1, Y2) between the suction vents (32a) and the yarn joining nozzle (31) in the up-down direction.

Claims

1. A yarn joining device (21) comprising:

a yarn joining nozzle (31) having a yarn joining space (31a) extending in a predetermined direction;

two clamps (42A, 42B) each arranged on either side of the yarn joining nozzle (31) in the predetermined direction for gripping a corresponding yarn;

two cutters (41A, 41B) each arranged on either side of the yarn joining nozzle (31) in the predetermined direction for cutting the corresponding yarn;

two untwisting pipes (32A, 32B) each having a suction vent (32a) arranged between the yarn joining nozzle (31) and the corresponding cutter (41A, 41B) in the predetermined direction for sucking a yarn end of the corresponding yarn gripped by the corresponding clamp (42A, 42B) and cut by the corresponding cutter (41A, 41B);

a control section (5); characterized by

a yarn shrinkage suppression mechanism (37A, 37B) capable of moving so as to contact the yarns between the suction vents (32a) and the yarn joining nozzle (31) in the predetermined direction, wherein

the control section (5) is adapted to cause the cutters (41A, 41B) to cut the yarns while the yarn shrinkage suppression mechanism (37A, 37B) is in contact with the yarns.

2. The yarn joining device (21) as claimed in Claim 1, wherein the yarn shrinkage suppression mechanism (37A, 37B) is adapted to grip the yarns.

3. The yarn joining device (21) as claimed in Claim 2,
further comprising a pulling member (35A, 35B) that is adapted to pull out from the untwisting pipes (32A, 32B) the yarn ends sucked into the untwisting pipes (32A, 32B),
wherein the control section (5) is adapted to cause the yarn shrinkage suppression mechanism (37A, 37B) to grip the yarns while the yarn ends are pulled out from the untwisting pipes (32A, 32B) by the pulling member (35A, 35B).

4. The yarn joining device (21) as claimed in Claim 3, wherein the yarn shrinkage suppression mechanism (37A, 37B) is adapted to grip the yarns with such a force that the yarn ends pulled out from the untwisting pipes (32A, 32B) by the pulling member (35A, 35B) slip through the yarn shrinkage suppression mechanism (37A, 37B).

5. The yarn joining device (21) as claimed in Claim 2,
further comprising a pulling member (35A, 35B) that is adapted to pull out from the untwisting pipes (32A, 32B) the yarn ends sucked into the untwisting pipes (32A, 32B),
wherein the control section (5) is adapted to cause the yarn shrinkage suppression mechanism (37A, 37B) to release the grip on the yarns before causing the pulling member (35A, 35B) to pull out the yarn ends from the untwisting pipes (32A, 32B).

6. The yarn joining device (21) as claimed in any one of Claims 2 to 4, wherein the yarn shrinkage suppression mechanism (37A, 37B) is adapted to grip the yarns by sandwiching the yarns between itself and a support member (30) that supports the yarn joining nozzle (31) .

7. The yarn joining device (21) as claimed in Claim 6, wherein the yarn shrinkage suppression mechanism (37A, 37B) includes two yarn shrinkage control levers (37A, 37B) that are adapted to pivot around a first pivot shaft (44) that extends in the predetermined direction.

8. The yarn joining device (21) as claimed in Claim 7, further comprising a biasing member that is adapted to bias the yarn shrinkage control levers (37A, 37B) toward the support member (30).

9. The yarn joining device (21) as claimed in Claim 8,
further comprising a regulating member capable of rotating around the first pivot shaft (44) while regulating a movement of the yarn shrinkage control levers (37A, 37B) in a biasing direction of the biasing member,
wherein the yarn shrinkage control levers (37A, 37B) and the regulating member are relatively movable in the biasing direction.

10. The yarn joining device (21) as claimed in Claim 8 or 9, further comprising an adjustment member capable of adjusting a biasing force of the biasing member.

11. The yarn joining device (21) as claimed in any one of Claims 7 to 10,
further comprising two yarn shifting levers (35A, 35B) each capable of pivoting around a second pivot shaft (43) that extends in the predetermined direction and adapted to introduce the yarns into the yarn joining space (31a),
wherein the first pivot shaft (44) of the yarn shrinkage control levers (37A, 37B) and the second pivot shaft (43) of the yarn shifting levers (35A, 35B) are arranged on opposite sides with respect to the yarn joining nozzle (31).

12. A yarn winding device comprising:

a yarn supplying unit (11) adapted to supply a yarn;

a winding unit (13) that is arranged at a position separated from the yarn supplying unit (11) in the predetermined direction and adapted to wind the yarn supplied from the yarn supplying unit (11) ; and

the yarn joining device (21) according to any one of Claims 1 to 11 arranged between the yarn supplying unit (11) and the winding unit (13) in the predetermined direction.

13. Method of operating a yarn joining device (21) comprising:

a yarn joining nozzle (31) having a yarn joining space (31a) extending in a predetermined direction;

two clamps (42A, 42B) each arranged on either side of the yarn joining nozzle (31) in the predetermined direction for gripping a corresponding yarn;

two cutters (41A, 41B) each arranged on either side of the yarn joining nozzle (31) in the predetermined direction for cutting the corresponding yarn;

two untwisting pipes (32A, 32B) each having a suction vent (32a) arranged between the yarn joining nozzle (31) and the corresponding cutter (41A, 41B) in the predetermined direction for sucking a yarn end of the corresponding yarn gripped by the corresponding clamp (42A, 42B) and cut by the corresponding cutter (41A, 41B);

a control section (5); characterized by the following steps:

moving a yarn shrinkage suppression mechanism (37A, 37B) so as to contact the yarns between the suction vents (32a) and the yarn joining nozzle (31) in the predetermined direction; and

cutting the yarns while the yarn shrinkage suppression mechanism (37A, 37B) is in contact with the yarns.

14. The method as claimed in Claim 13, wherein the yarn shrinkage suppression mechanism (37A, 37B) grips the yarns.

15. The method as claimed in Claim 14,
further comprising pulling out from the untwisting pipes (32A, 32B) the yarn ends sucked into the untwisting pipes (32A, 32B), and
gripping the yarns while the yarn ends are pulled out from the untwisting pipes (32A, 32B) by the pulling member (35A, 35B).

Drawing