EP0219388A1 - Device for conveying a stack of material along a sewing station - Google Patents

Abstract

The device individually presents one edge of a stack of pieces of material and is intended particularly for attachment to a sewing station. The device consists of a table (6) on which the stack of pieces rests. A clamp (8) gripping one edge of all the articles is fixed to one edge of the table. The table (6) moves with respect to the sewing table (15) in such a way that the second edges can be brought in turn under the sewing head of the machine (4) and, after sewing, hang between the table (6) and the table (15). <IMAGE>

Description

The present invention relates to a presentation device one by one of the edges of pieces of a stack intended in particular, but not exclusively, to be attached to a sewing station.

We know that in the making, the sewing operations are repetitive, the same sewing operation having to be carried out on a set of pieces which are conveyed, preferably in the form of a pile, on the post considered and which must also be removed stacked to facilitate the work of the next station. The worker must therefore take a piece from the input stack, place it on her sewing machine, perform the required work, then, when it is finished, replace the piece on an output stack. Besides that these manipulations are long and harm the productivity of the station, the stacking of textile pieces with a good alignment always poses problems because of the lack of rigidity and the adhesion of these.

The object of the present invention is to overcome this drawback and to allow a gain in productivity. It is based on the observation that in a production line the same operation must be carried out, on identical parts in the same places and that only the parts on which work must be carried out must be taken in hand and guided in a way precise.

It is known, for example from US-A-3 257 978 to temporarily assemble pieces by immobilizing one of their edges with a clamp which constitutes a sort of temporary binding, the sewing work being carried out on the edge opposite.

The article in the Dutch review "CONFECTIE" Vol.14 N ^D 10, pages 706-708 published under the signature of AGA KRUMME and entitled: "Mechanisering en deelautomatisering van het naairproces" represents in Fig.13B a trolley fitted with casters making it possible to constitute a battery, the parts of which can be connected by a clamp controlled by a pedal. But this carriage is intended to receive the parts at the outlet of a sewing machine.

According to the present invention, the device for presenting sewing pieces for a sewing station comprising a table on which is disposed a sewing machine the device comprising a clamp. Capable of grasping the edges of a set of pieces is characterized in that 'it includes a laying table for the stack of workpieces arranged' parallel to, and integral with the sewing table, the table being freely movable parallel to the direction of travel of the pieces under the sewing head and, under the action of a jack, perpendicular to this direction.

The articles of the stack are thus joined by one of their edges, inside the clamp while their opposite edges can pass successively under the sewing head. In its simplest version, the table is moved by hand by the worker, as and when the seams are executed parallel to the direction of travel of the pieces under the sewing head. rubbing the passage of the article. However, it is possible to automate the translational movements of the laying table and to index them on the sewing operations.

Also, according to another characteristic of the invention, the lateral movement of the laying table is controlled by an automaton, placed under the dependence of a cell for detecting the end of a seam operation, the automaton acting on a jack whose body is secured to the sewing table and whose rod is secured to the laying table.

For example, in the case of the fitting of a collar on a vest, the work consists in sewing the collar on the openings of the neck and on the openings of passage of the arms. In this case, the machine is preset to consider that the end of operations is after the three seams have been executed. It then actuates a pneumatic or other actuator which moves the support away from the table of the sewing machine. The worked part of the sewn piece falls or is pushed between the table and the support. After the laying table has moved closer to the sewing table, the operator takes the edge opposite to that which is held by the clamp of the next piece and places it on the machine table while doing so rotate around the clamp.

When all the parts of the stack have been worked, a pedal control, for example, allows the clamp to be opened by means of a jack or the like. The worker can then take the stack and place it on a conveyor belt. The present invention thus makes it possible to work on a stack of textile pieces without having to destroy this stack. The pliers make a sort of temporary binding and the pieces are selected from the stack like the pages of a book, turned one by one. We can thus save considerable time on a particular operation to be performed on a set of stacked parts.

According to another characteristic of the invention, the device is characterized in that its movable members are mounted to slide on sliding rods by means of ball bushings.

It is thus possible to proceed to very long seams by moving by hand ', without effort, the laying table on its support so as to follow the evolution of the piece under the sewing head.

• - La Fig.1, une vue du dispositif en perspective par l'arrière de la machine à coudre,en position de travail correspondant à l'une des étapes du cycle de travail;
• - La Fig.2, dans les mêmes conditions, le dispositif en position d'opération;
• - La Fig.3, un schéma montrant le coulissement de la table lorsque la couture à effectuer est de grandes dimensions;
• - La Fig.4, une vue du dispositif lors de l'extraction de la pile travaillée avec ouverture de la pince.

Other characteristics and advantages of the present invention will appear during the description which follows of a particular embodiment, given solely by way of nonlimiting example, with reference to the drawings which represent:

• - Fig.1, a perspective view of the device from the rear of the sewing machine, in the working position corresponding to one of the stages of the working cycle;
• - Fig.2, under the same conditions, the device in the operating position;
• - Fig.3, a diagram showing the sliding of the table when the seam to be made is large;
• - Fig.4, a view of the device during the extraction of the worked pile with opening of the clamp.

In Fig. 1 and the other figures, it can be seen that the stack P of parts or articles to be worked is placed on a laying or stacking table 6 of rectangular shape, one large side of which is arranged parallel to a small side of the sewing table 15 carrying a sewing machine 4. The lower end of the stack P is trapped in a clamp 8 secured to the table 6 and located on the side of the sewing table 15. A part of the pieces constituting the stack ( the pieces already worked) is arranged (in Fig.l), vertically between the stacking table 6 and the sewing table 15 while the pieces which are to be sewn rest on the table 6, at least partly in a position horizontal.

The table 6 is mounted on a support 7 in the form of a square, the horizontal branch 14 of which carries ball bushings 20, preferably three in number, in which slide rods integral with the table slide. On the vertical branch of the support 7 is mounted a plate 13 on which is fixed the head 12 of a jack 5 whose body is secured to the frame supporting the sewing table 15 and the sewing machine 4. The plate 13 is itself secured to sockets balls 19 sliding on two horizontal slides 10 fixed to the feet 16 of the table 15, perpendicularly to the longitudinal direction of the latter and joined at their opposite ends by a stiffening crosspiece 17. The jack 5 extends parallel to the slides 10. Tables 6 and 15 are substantially at the same level, the length of the articles usually allowing the edge to be sewn below the sewing head. In the case of very high batteries, it is however possible to provide a device for adjusting the height of the table 6 relative to its support 7 which can be either manual or automatic.

Below the table 15, is also fixed an automaton A intended to control the displacement in translation of the table 6, according to information received from the sewing table 15, by acting on the jack 5. In the example represented, the automaton A is a pneumatic control automaton but it can also control all types of jacks, hydraulic, electrical, mechanical, etc. For this purpose, the table receives information from two photoelectric cells 1 and 2, arranged respectively in front and behind the sewing head of machine 4, the words in front and behind being understood for an article to be sewn. These cells provide information about the start of the seam and the end of the seam. In the case where the operation consists in the insertion on the edge of the article of an elastic band or laminette or the laying of a continuous textile band or collar, it is necessary to cut the continuous band in order to separate the articles. This cut is made using a guillotine knife 3 controlled by a jack (not referenced) itself controlled by the machine A receiving pulses from cell 2.

The clamp, located between the stacking table 6 and the sewing table 15 consists of a plate 8 hinged on a hinge 18 and able to pivot under the action of a third jack 11 whose body is secured to a transverse edge from table 6. The jack 11 can be controlled either by the automaton A or by a pedal located below the sewing machine and which the operator operates when all the garments in the stack have been sewn. In fact, given the variations that can occur in the height and number of items in a stack, the second solution may be preferable in some cases. When the cylinder 1 ₁ is controlled by the automaton A, the latter can count the articles, if the number of articles in the stack has been previously entered in memory. Indeed, the number of operations of the jack 5 is available in the automaton which knows how many times the piston of the jack 5 has been actuated. It is also possible to provide at the upper part of the table 6 a sensor (not shown) indicating to the machine if at least one textile piece to be sewn is on the table or not. When no part is on the table, a signal is sent to the automaton which acts on the jack 11 to open the clamp after the table 6 has been moved away from the table 15 through an adequate timing circuit allowing the worker grabbing the pile before the clamp opens.

• à partir de la position représentée sur la Fig.1, l'automate, envoie au vérin 5 une pression conduisant à la rétractation de la tige de vérin à l'intérieur du corps de celui-ci. A la fin de ce mouvement, comme représenté sur la Fig.2, la table 6 s'est rapprochée de la table 15. L'ouvrière saisit le bord extérieur de l'article se trouvant à la partie supérieure de la pile P et l'amène sur la table de couture 15, les opérations de couture commençant lorsque l'avant du tissu passe au-dessus de la cellule 1 qui déclenche le fonctionnement de la machine. L'opération se poursuit jusqu'à ce que le passage du bord arrière de la pièce à coudre soit détecté par la cellule 2. Cette détection, transmise à l'automate A se traduit par deux effets : le couteau 3 est actionné et coupe la bande continue, lorsqu'elle existe ; l'automate A actionne le vérin 5 ce qui se traduit par l'éloignement de la table 6, la pièce cousue pouvant tomber sous son propre poids entre les tables 6 et 15, si sa hauteur est inférieure au déplacement de la table 6, ou être poussé vers le bas par l'ouvrière. Bien entendu, la table 6 ne doit pas venir en contact avec la table 15, mais elle doit laisser un espace suffisant pour que tous les articles de la pile puissent venir tomber entre les deux tables. Au demeurant, les articles sont disposés de sorte que leur plus grande longueur soit sensiblement parallèle à la direction ce la machine à coudre.

The operation of the device is as follows:

• from the position shown in Fig.1, the automaton sends a pressure to the jack 5 leading to the retraction of the jack rod inside the body thereof. At the end of this movement, as shown in Fig.2, the table 6 has moved closer to the table 15. The worker grips the outer edge of the article located at the top of the stack P and l 'brings to the sewing table 15, the sewing operations starting when the front of the fabric passes over the cell 1 which triggers the operation of the machine. The operation continues until the passage of the rear edge of the workpiece is detected by cell 2. This detection, transmitted to the machine A results in two effects: the knife 3 is actuated and cuts the continuous strip, where it exists; the automaton A actuates the jack 5 which results in the distance from the table 6, the sewn piece being able to fall under its own weight between the tables 6 and 15, if its height is less than the displacement of the table 6, or to be pushed down by the worker. Of course, the table 6 must not come into contact with the table 15, but it must leave sufficient space so that all the articles of the stack can come to fall between the two tables. Moreover, the articles are arranged so that their greatest length is substantially parallel to the direction of the sewing machine.

However, it sometimes happens that the length of the seams is such that it is necessary to move the workpiece parallel to the edge of the table 15. This necessity would normally lead to extracting the article from the stack, which is contrary to the desired result. Also, according to a characteristic of the invention, the table 6 is movable in translation relative to its support and in a direction substantially orthogonal to the movement of the latter. Of course, the two movements are perfectly independent, the table 6 moving only when the worker exerts traction on the fabric in order to move it under the sewing head of the machine 4. Such movement of the table 6 by relative to its support is shown in Fig. 3. Given the mounting of the table 6 by means of the slides 9 sliding in ball bushings 20, this translational movement encounters no mechanical resistance.

Fig.4 shows the end of the sewing operations performed on a stack of articles, all articles occupying a vertical position and being held at their upper part by the clamp 8, before opening thereof. The opening of the clamp 8 results, as indicated above from the action of the jack 11 controlled either by the automaton A or by a pedal (not shown). The worker can then grasp, before opening the clamp, the complete stack, open the clamp and arrange the stack of parts on a conveyor belt or the like, with a view to its transfer to the next work station. While the clamp is still open, the worker introduces the edge of the next pile on which no work is to be carried out between the clamp 8 and the table 6. The operations can then resume.

Claims (6)

1 ° Device for presenting sewing pieces for a sewing station composed of a frame supporting a table (15) on which is placed a sewing machine (4) the device including a clamp (8) capable of grasping the edges of a set of pieces (P), characterized in that it comprises a laying table (6) for the stack of pieces (P) to be worked arranged parallel to and integral with the sewing table (15), the table (6 ) being freely movable parallel to the direction of travel of the parts under the sewing head and, under the action of a jack (5), perpendicular to this direction. 2 ° Device according to claim 1, characterized in that the lateral movement of the laying table (6) is controlled by an automaton (A), placed under the dependence of a detector (2) of end of operation of a seam, the automaton (A) acting on the jack (5) whose body is integral with the frame (16) of the sewing table (15) and whose rod (12) is integral with the laying table (6 ). 3 ° Device according to one of claims 1 or 2, characterized in that the sewing table (15) is provided, on either side of the sewing machine (4) with two photoelectric cells (1,2) , the cell (2) connected to the automaton (A) causing on the one hand the cutting of a continuous strip by a knife (3) and, on the other hand, the distance from the stacking table (6 ) relative to the sewing table (15). 4 ^r Device according to any one of the preceding claims, characterized in that the sliding members (6,7) are mounted on sliding rods (9,10) by means of ball bushings (19,20). 5. Device according to any one of the preceding claims, characterized in that the clamp (8) is controlled by a jack (11) controlled by a pedal. 6 ° Device according to any one of claims 1 to 5, characterized in that the clamp (8) is controlled by a jack (11) controlled by the machine (A).

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