|
(11) | EP 1 178 143 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
|
|
|
|
|||||||||||||||||||||||
| (54) | Method for detecting the orientation of a textile product having two different ends, apparatus for implementing said method and orientator device associated with said apparatus |
| (57) System for sensing the orientation of a product, especially of a textile article
such as a stocking, a sock and the like having a first and a second differently shaped
ends, for detecting which of the two ends is forward along a preset work and/or transfer
path. The system includes the following operating steps: - subjecting each product
to a first reading and a second reading by optical detection means disposed along
at least a first front of reading transverse with respect to said work and/or transfer
path, said readings being carried out on the foremost portion of the product along
a direction of relative advancement thereof with respect to said optical means; -
comparing the result of said first and second readings for checking any coincidence
between the two radings; - emitting a signal relevant to the identification of either
the first or second end in correspondence, respectively, of the coincidence or non-coincidence
of the two readings. |
[0001] The present invention refers to a method for detecting the orientation of a textile product having two different ends, an apparatus for implementing said method and an orientator device associated with said apparatus.
[0002] The invention is advantageously applicable in detecting and possibly reversing the orientation of tubular bodies such as stockings, socks and the like, upon any step of their production process in which it is necessary to recognize, for example, whether it is the toe or the elastic hem or garter to come forward first. One of said steps may be the one relative to the output of said articles from the machine producing them, when it is necessary to determine the orientation of the same articles in order to act consequently upon successive production steps. In case of a stocking or a sock, for example, it may be suitable or even necessary to know whether the front end of the product arriving at a given work station is either its toe or elastic hem.
[0003] Apparatuses able to recognize the orientation of a textile product are known from documents US 5165355 and US 5040475.
Such apparatuses are rather complex, take up large spaces and are relatively difficult and costly to make.
[0004] One object of the present invention is to provide a method for detecting the orientation of tubular products and an apparatus of simple construction and great reliability for implementing said method.
[0005] A further object of the invention is to provide a particularly simple and cost-effective device able to orient the products in the same way all the time.
[0006] This result has been achieved, according to the invention, by providing an operating method, an apparatus and a device having the characteristics disclosed in the independent claims. Further characteristics being set forth in the dependent claims.
[0007] Among the advantages offered by the present invention there is the fact that the detection method and procedures, as well as any possible reversal of product's orientation, are extremely reliable; that the apparatus and the device made according to the invention exhibit a structure of relatively limited overall dimensions and are able to be easily placed also in correspondence of small-size machines; that the substantially simple operation of the apparatus and device in question brings about advantages in their fabrication and utilization; that the apparatus and device exhibit few parts subject to wear and maintain their novel characteristics unchanged also after a prolonged service life, while requiring a very limited maintenance or no maintenance at all.
[0008] These and other advantages and characteristics of the invention will be best understood by anyone skilled in the art from a reading of the following description in conjunction with the attached drawings given as a practical exemplification of the invention, but not to be considered in a limitative sense, wherein:
- Figs. 1A, 1B, 1C and 1D are schematic top views of a first embodiment of the apparatus according to the invention, in four different operating conditions;
- Fig. 2 shows a table relating to the operative conditions illustrated in the preceding figures;
- Figs. 3A, 3B, 3C and 3D are schematic top views of a further embodiment of an apparatus according to the invention, in four different operating situations;
- Fig. 4 shows a table relating to the operative conditions illustrated in Figs. 3A to 3D;
- Figs. 5A and 5B are a longitudinal section view and a cross section view of an apparatus according to the invention for detecting and possibly reversing the orientation of tubular products, such as sotckings and socks, in a possible operating condition;
- Figs. 6A and 6B are views similar to those of Figs. 5A an 5B but related to a different operating condition;
- Figs. 6C-6E are three longitudinal section views of the device of Fig. 6A, according to configurations thereof taken up in the three successive steps;
- Figs. 7A and 7B are a longitudinal section view and a cross section view of the device in question, which show the step in which the product is moving away with the hem portion being forward;
- Fig. 8 is an enlarged detail of the device of Fig. 6C;
- Fig. 9 is a simplified block diagram of the means provided for controlling the operations.
[0009] With reference to the figures of the attached drawings, an apparatus constructed according to the present invention includes a conduit (1) wherein the products (2) are made to move, for example by suction in the direction of arrow (A). The conduit (1) has an input (I) and an output (U) sections for the products. Each product (2), at the inlet of the conduit (1), goes through two motor-driven rollers (3) whose function is to introduce the individual products (2) into the conduit (2) at a preset speed and possily retain them for a preset time.
Said rollers (3) are oriented orthogonally to the longitudinal axis of the conduit (1) and are disposed in correspondence of the products' input section (1). The motion of the products (2) inside the conduit (1) is obtainable by a suction applied in correspondence of a spout (10) allowing the connection thereof to an aspirator (not shown).
[0010] The portion of the conduit (1) in correspondence of the input section (I) has a convergent-divergent development to achieve a stream of air which contribute to maintain the products (2) stretched at the station where optical means, to be described later, are provided. Possibly provided in succession to said convergent-divergent length are other lengths located downstream to further increase such stretching effect. The products (2) arrive at the input station (I) of conduit (1) conveyed therein via another conduit, not shown in the drawings, by a stream of air inside. Similarly, the products exiting from section (U) of conduit (1) are carried along by a stream of air inside a further conduit. Possibly provided in correspondence of products (2)'s output section (U) is a pair of motor-driven roller (30), parallel to those (3) of input section (I), to engage the incoming products and move them in the exit direction.
The product (2) exhibits a first and a second differently shaped ends corresponding, respectively, to the elastic band or hem (4) and to the toe (5).
[0011] Referring now specifically to Figs. 1A-1D, the product (2), after passing the rollers (3), comes to a detection station wherein a plurality of photocells (F1, F2, F3, F4, F5, F6) making up the optical detection means.
[0012] It will be appreciated that the photocells shown in the embodiment are in number of six only by way of example, as their number can be suitably varied as required. Said photocells are disposed according to a reading front located across the product's path, that is, transversally to the conduit (1) represented in the figures. In this embodiment, two readings are carried out by the photocells thanks to timing means (T) which require the reading signal twice from the photocells, in order to supply suitably connected processing means (MP) with the signal coming from the photocells upon two subsequent instants (t0, t1) corresponding, respectively, to the readings made on a portion of the product and to the portion further downstream of the direction (A) of origin. With reference to Figs 1A and 1B, the first reading (t0) determines the interception (represented with ON in Fig. 2) of the four central photocells (F2, F3, F4, F5) but not of the outermost ones (f1, F6) (OFF condition of Fig. 2). Upon the second reading (t1), all the six photocells result intercepted (position ON in Fig. 2). The second reading is made after putting the product (2) one step forward, this movement, during the two reading steps, being controlled by the rollers (3). The programmable processing means (MP) make it possible to evaluate the difference between the two detections (a difference being determined, in this example, by the fact that the product (2) presents its toe forward) in order to establish which of the two product's ends runs along first across the photocells' reading station. Practically, the processing means can assess the width (1) of the end presented downstream the product. In case the product presents its elastic band or hem (4) forward, as in the example of Figs. 1C and 1D, the said photocells will emit the same signal in both the readings (t0, t1) being carried out (again ON in Fig. 2). The processing means (MP), then, receive the same type of signal from all the photocells (F1, ..., F6) and reveal therefore that the product has its elastic band or hem (4) forward.
[0013] In the example illustrated in Figs. 3A-3D, the detection station has two reading fronts disposed parallel between them and transversally to the conduit (1). In this example, there is provided a first set of photocells (F1, F2, F3, F4, F5, F6) upstream and a second downstream (F7, F8, F9, F10, F11, F12).
[0014] In this embodiment of the invention (Figs. 3A-3D), the two readings carried out by the station (6) could be simultaneous and the consequent difference assessment by the processing means be made over the readings carried out by the two reading fronts at the same moment. The apparatus carries out a simultaneous detection on both the reading fronts, with the product being disposed as represented in Figs. 3B and 3D, that is, with the foremost end of the product having reached the reading front disposed downstream thereof.
[0015] In case a product (2) having its toe (5) ahead, as in Figs. 3A and 3B, the processing means (MP) detect the differences existing between the readins carried out on the two fronts (positions ON or OFF of Fig. 4).
In particular, in the configuration shown in Fig. 3B, that is, upon the presentation of the toe of the product (2), the reading of the first front (F1-F6), disposed upstream, corresponds to the interception of all the corresponding photocells (F1 to F6), while the reading of the second front (F7-F12), disposed downstream thereof, corresponds to the interception of the central photocells (F8, F9, F10, F11) only.
[0016] The operation will be analogous for the product presenting its elastic hem (4) downstream, as shown in Figs. 3C and 3D, with the processing means (MP) which, in this case, will detect the concordance of the readings by the photocells of the two fronts (positions On of Fig. 4).
In other words, if the product (2) comes along with its elastic hem (4) forward, then the photocells of each front (F1-F6; F7-F12) will all generate the same type of signal. Otherwise, if the product presents itself with the toe forward, then the photocells of one of the two fronts will deliver signals of a type different from that of the other front.
[0017] Obviously, the relative motion cited above between the product and the optical detection means, allows also to move the latter with respect to the product. This is possible, for example, by disposing the detection means upon a carriage able to move relative to the product (2), the latter being kept temporarily in fixed reading position by the rollers (3), and by providing the conduit (1) with a reading window for the photocells.
With the above described apparatus, a device can be advantageously associated able to reverse the orientation of the product (2) in case the latter should result oriented in a manner other than the one desired. The device in question, according to the embodiment shown in Figs. 5A-8, is part of the said conduit (1). More precisely, provision is made for a chamber (7) separated from the conduit (1) by a lamina (8). The latter has one free end (80) and the other (81) is connected to a lever (82) which, in turn, is hinged on a journal (83) orthogonal to the products' direction of advancement (A). The said other end (82) of the lever is engaged with the stem of a pneumatic actuator (9) housed within the camera (7). The latter is provided with a spout (70) allowing the connection thereof to the air suction system to which the main spout (10) of conduit (1) is also connected via corresponding solenoid valves (V70, V10). The lamina (8) is, in practice, part of the wall of conduit (1), and the lamina/actuator assembly (8, 9) makes up a pneumatically-operated, normally closed valve which allows a door (represented in this case by the same lamina (8)) between the conduit (1) and the chamber (7) to be closed and opened. The actuator (9) is associated with said processing means (MP) which command the operation thereof in response to signals coming from the photocells provided for the identification of the actual orientation of the products (2).
In practice, the cases possibly occurring are the following.
[0018] If the product (2) enters the conduit (1) with the hem (4) forward, and it is preferred that the product exits therefrom in this fashion, then the programmable unit (MP), correspondingly informed by the above described photocells, leaves the door (8) closed and the product is allowed to pass along the conduit (1) up to the rollers (30) of the output section (U), the rollers taking over the product and moving it away. This case is illustrated in the drawings of Figs. 5A, 5B, 7A and 7B.
[0019] If the product (2) enters the conduit (1) with the toe (5) ahead (Figs. 6A, 6B), the corresponding detection is transmitted from the photocells to the programmable unit (MP) which provides for excluding the suction through the main spout (10) by closing the respective solenoid valve (V10), operating the actuator (9) to open the door (8), and activating the suction through the spout (70) of chamber (7) by opening the relevant solenoid valve (V70). This condition is illustrated in Fig. 6C. Following this, and after a preset time, the programmable unit (MP) operates the closing of the door (8), so that the foremost portion of the product (2) results inside the chamber (7) and is kept therein by the free end (80) of the lamina. Moreover, the unit (MP) starts again the suction through the main spout (10) and cuts off the suction through the spout (70) of chamber (7), as can be seen in Figs. 6D and 6E. Following this, the orientation of the product (2) being reversed, the same product can be moved away, with the hem (4) portion being forward as desired, by means of the output rollers (30).
[0020] The moving away of the product can be made easier by means of a jet of compressed air generated by a nozzle (6) acting within the conduit (1) at a location intermediate between the door (8) and the output section (U).
[0021] It will be appreciated that the above mentioned operations are reversed when it is required to let the product exit from the conduit (1) with its toe portion forward.
The operation of said device, as far as the orientation detection of the product is concerned, is identical to that described with reference to Figs. 1A-1D.
The programmable means (MP) are of conventional type, that is, of a type well known to those skilled in industrial automation and, accordingly, will not be described in greater details.
[0022] Alternatively, in the place of the photocells previously described, a telecamera (TE) may be provided of a type available on the market (and, for this reason, not to be described in detail), connected to the programmable processing means (MP) and able to detect the image of the end of the product in transit from the reading station. In this case, the image detected by the telecamera (TE), relating to the product in transit at that moment, is compared with a reference image suitably memorized by the processing means (MP) and related, for example, to a given build or size of the sock to be treated. In other words, the processing means (MP) are provided with a memory in which at least a reference object or parameter can be stored and consisting, in this case, of an image to be compared with that coming from the telecamera (TE). From a comparison between the two images it is possible to determine whether the end at the reading station relates to a toe or a hem. In the comparison between the two images, one or more reference parameters may be considered such as, for example, the length (1) of the end (shorter for the toe, longer for the hem), the disposition of the edge of the product's end (curved for the toe, straight for the hem), etc. Such parameters related to the telecamera can also be used for the photocells since, by knowing a given reference reading for the type of product in the course of treatment, it is possible to draw the corresponding parameter by taking into account the number of photocells involved, that is, the number of optical axes intercepted by the product. Assuming that six photocells correspond to the width of the product in correspondence of its hem, the interception operated by a number of photocells less than six will cause the processing means to establish that such end relates to the toe; on the contrary, the interception by six photocells will correspond to the detection of the hem. In conclusion, the reference object or parameter stored in memory may be a numeric value, an image or other, and can be compared with detections carried out by photocells, telecameras or other optical means.
- subjecting each product to a first reading and a second reading by optical detection means disposed along at least a first front of reading transverse with respect to said work and/or transfer path, said readings being carried out on the foremost portion of the product along a direction of relative advancement thereof with respect to said optical means;
- comparing the result of said first and second readings for checking any coincidence between the two;
- emitting a signal relevant to the identification of either the first or second end in correspondence, respectively, of the coincidence or non-coincidence of the two readings.
- optical detection means consisting of a plurality of optical interception means disposed according to a preset order, that is, defining at least one reading front, and each being able to emit a signal in correspondence of the detection being carried out, that is, of the occurred interception;
- driving means for moving said detection means relative to a product to be examined, and being able to subject the product to the action of said detection means;
- processing means able to determine, based on a comparison between two sets of signals relevant to two readings by said optical means, the presence of either said first end or said second end, that is, able to determine the orientation of the product based on the product's interception occurred upon the two readings being carried out.
- subjecting each product to a reading by optical detection means disposed along a reading front transverse with respect to said work and/or transfer path, said reading being carried out on the foremost portion of the product along a direction of relative advancement thereof with respect to said optical means;
- comparing the result of said reading with an object or parameter, previously stored into memory means, and corresponding to a preset reference sample for checking any coincidence thereof;
- emitting a signal relevant to the identification of either the first or second end in correspondence, respectively, of the coincidence or non-coincidence between the reading being carried out and said object or parameter.
- optical detection means consisting of a plurality of optical interception means disposed according to a preset order, that is, defining at least one reading front, and each being able to emit a signal in correspondence of the detection being carried out, that is, of the occurred interception;
- driving means for moving said detection means relative to a product to be examined, and being able to subject the product to the action of said detection means;
- memory means able to store at least one object or parameter for comparison;
- processing means able to determine, based on a comparison between two sets of signals received from said optical detection means and said object or parameter, the presence of either said first end or said second end, that is, able to determine the orientation of the product based on the correspondence or non-correspondence between the product's interception signals by the optical means and the stored object or parameter.
- optical detection means consisting of a plurality of optical interception means disposed according to a preset order, that is, defining at least one reading front, and each being able to emit a signal in correspondence of the detection being carried out, that is, of the occurred interception;
- driving means for moving said detection means relative to a product to be examined, and being able to subject the product to the action of said detection means;
- processing means able to determine, based on a comparison between two sets of signals received from said optical detection means and said object or parameter, the presence of either said first end or said second end, that is, able to determine the orientation of the product based on the occurred interception of the product upon the two readings being carried out;
- means for reversing the orientation of the product, disposed and acting along said path, and connected to said processing means so as to reverse the orientation of the product when the latter does not present itself in the desired orientation.
- optical detection means consisting of a plurality of optical interception means disposed according to a preset order, that is, defining at least one reading front, and each being able to emit a signal in correspondence of the detection being carried out, that is, of the occurred interception;
- driving means for moving said detection means relative to a product to be examined, and being able to subject the product to the action of said detection means;
- memory means able to store at least one object or parameter for comparison;
- processing means able to determine, based on a comparison between two sets of signals received from said optical detection means and said object or parameter, the presence of either said first end or said second end, that is, able to determine the orientation of the product based on the correspondence or non-correspondence between the product's interception signals by the optical means and the stored object or parameter;
- means for reversing the orientation of the product, disposed and acting along said path, and connected to said processing means so as to reverse the orientation of the product when the latter does not present itself in the desired orientation.