METHOD FOR AUTOMATIC SEWING OF ZIPPERS AND AN AUTOMATIC SEWING MACHINE FOR ACCOMPLISHING THE METHOD

Abstract: A method to automatically transfer garments from a putting-up table (14) to a sewing machine (34) for automati­ cally sewing zippers (38). Horizontally overlying edges (13) of garments extending outside a putting-up table are gripped by gripping bars (27) of a gripping appliance (21) which, by a 90° rotation, brings said edges (13) within the reach of the trans­ port device (36) of the sewing machine (34) so as to sew zippers onto said edges (13).

Description: METHOD FOR AUTOMATIC SEWING OF ZIPPERS AND AN AUTOMATIC SEWING MACHINE FOR ACCOMPLISHING THE METHOD The present invention refers to a method to automatically guiding garments from a putting-up-table to a sewing machine for sewing of zippers, and also an automatic sewing machine for accomplishing the method and which includes a device for feeding of the garments and for sewing of a zipper fastener to these by means of a sewing machine. BACKGROUND OF THE INVENTION Sewing of zippers is a relatively difficult operation and requires a long time of training. Of this reason different types of automatic sewing machines have been developed, which may be operated by unqualified labour force after a short time of training. The operator. however, has to manually guide the material during the sewing operation, whereby the working pace is low and the production small. At known automatic sewing machines for sewing of zippers. the zippers are always located lowest, i.e. nearest the bottom plate. while the garment which should be provided with the zipper is located above it. The reason to this location is that this is the most simple to transport and guide the zipper-band. A drawback with this type of device is that the zipper-band and the garment being different stretched, why an even seam is very hard to achieve, especially if the garment is of elastic material. It has also been tried to arrange brake-devices, which should obstruct extensions in the material, but only with a little success. THE OBJECT OF THE INVENTION AND ITS MOST IMPORTANT CHARACTERISTICS The object of the invention is to provide a method of automatically guiding the garment and the zipper to the sewing machine, in such a way that the manual guidance and thereby also the extensions in the material are eliminated. A further object of the invention is to considerably increase the production capacity, and also make it possible to sew zippers in lined garments. This has been solved by that the edge parts of the garment along which a zipper is intended to be sewed, is located essentially horizontally. edge to edge and above each other, that a gripping device grips the garment along said edge part, a distance inside and essentially parallel to the edges and turn the garment to a vertical hanging position, that the side parts of the garment located beneath and above the gripping device are separated from each other by means of a separating device to a position essentially parallel to the gripping bars of the gripping device, that the edge parts of the garment are pressed of the gripping device and/or separate pressing bars against a transport device which guide the garment against a sewing machine, and that a zipper is provided from above to fit up against the edge parts of the garment, which with the zipper is provided to the press foot of the sewing machine for sewing. To accomplish the method described above is also proposed an automatic sewing machine which solves the problems mentioned above by means of, that a gripping device is arranged and formed to grip, by means of gripping bars outside a putting up table extending, horizontally on each other located edge parts of garments, along which edge parts a zipper is intended to be sewed, that the gripping device is turnable from one to its gripping bars vertical to a horizontal position, in which the press pinch betwen the gripping bars are located in the feeding direction of the sewing machine that a separating device is arranged to separate their side parts of the garment located on both sides of the gripping bars from each other, that the gripping device is disposable in the feeding direction of the sewing machine above a first transport device and formed to transfer the edge parts of the garment to this, that above the first transport device is located a second transport device by means of which zippers are transportable to fit up against the edge parts of the garment. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows a garment for example a blouse, in a view from above and which is intended to be provided with a zipper. Figure 2 and 3 show in perspective two phases during fetching of the garment. Figure 4 shows the putting-up-table according to the invention in a perspective view. Figure 5 shows the table according to figure 4 in a view from above, and on which table a garment has been located. Figure 6 shows a cross section along the line VI-VI in figure 5. Figure 7 shows a cross section along the line VII-VII in figure 5. Figure 8 shows a cross section analoguous with figure 7 through the putting-up-table with the gripping appliance in cross section and in fetching position. Figure 9 shows schematically a side view of a part of the automatic sewing machine. Figure 10 shows the automatic sewing machine in a view from above, but without the transport devices for the zippers and lining, if any. Figure 11 shows a cross section through the first transport device of the automatic sewing machine with the gripping appliance in delivery position. DESCRIPTION OF EMBODIMENTS The garment 11 shown in figure 1, which should be provided with a zipper, could be partly sewed with one seam 12, but is otherwise open laterally. The method according to the invention may however also be used at such garments. which yet are not sewed or where the zipper should extend along the entire length of the garment. The garment 11 is folded in such a way that its edge sections 13, at which the zipper is going to be sewed, are located edge to edge on each other and located on a putting-up-table 14, as is shown in figure 5. The putting-up-table is provided with a stop 15, which also forms an extension of the table top, which corresponds to the desired seam allowance. The stop is pivotable around a hinge 16 located at the underside of the table top. The stop is also provided with a mechanism (not shown) which may turn the stop from the position shown in figure 7, where it forms a stop for the edge section 13 of the garment to the position shown in figure 8, in which the stop has been turned to an inactive position beneath the table top. The putting-up-table 14 is also provided with two dividing plates 17 and 18 located at some distance from each other and from the table 14. which extend laterally over the table at its one front edge. The dividing plates 17 and 18 are bent upwards from each other at the end directed against the stop 15 forming a funnel-formed opening. As can be seen in figure 6 the garment 11 is located partly in direct contact to the stop 15 and the side parts 19 and 20 of the garment partly are separated at their upper end in such a way that the lower side part will be located beneath the dividing plate 18 while the upper side part will be located on the top of the dividing plate 17. A gripping appliance 21 is arranged at the side of the putting-up-table 14. which gripping appliance is displaceable in the direction to and from the putting-up-table. as is shown by the arrow 22, and partly it is displaceable in its longitudinal direction towards and from a first conveyor 23 in the direction of the arrow 24 and partly it is pivotable around its longitudinal axle around the arrow 25. The gripping appliance 21 consists of two transferring arms 26 which at their free ends are provided with gripping bars 27. The gripping appliance is pivotable from a position in which the gripping bars 27. which are brought together, are horizontal to a position in which they are located vertically. The automatic sewing machine includes also a separating device 28 comprising of two parts of which one dividing device 29 is located at the gripping appliance 21 and which comprises of a knife blade 31 pivotable around an axle 30, while the other dividing device 32 comprises of a plough formed tip located at the support 33 of the first transport device 23. In the transport position of the gripping appliance 21, i.e. when the gripping bars 27 are located horizontally the knife blade 31 of the separating device is located in front of the plough tip 32 and at a movement of the gripping appliance 21 in the direction of the arrow 24, i.e. towards the sewing machine 34, the knife blade 31 will be turned backwards against the action of r spring which is not shown. The first transport device 23 includes two parallel endless transport belts 35 and 36 which are arranged at a small distance from each other. Pressure bars 37 are arranged above these, which pressure bars can be pressed against the transport belts, and which are vertically adjustable so much that the gripping bars 27 of the gripping appliance 21 may be inserted between these and the transport belts 35, 36 resp. A second transport device 38 is arranged above the first transport device 23. The second transport device includes a not shown device for feeding of a zipper in the form of a band from a store spool, but it is also possible to feed zippers in pieces via the transport device. The last part of the transport device 38 shown in figure 9, comprises an inclined guiding chute 39, which opens just on this side of the press foot 40 of the sewing machine 34. If necessary there may further be a third transport device 41 in near connection to and above the second transport device 38 and which is used for feeding of a lining if any. THE FUNCTION OF THE AUTOMATIC SEWING MACHINE The only manual work which has to be executed is putting the side parts 19, 20 of the garment together in such a way that their edge sections 13 at which the zipper should be sewed on, are located edge to edge and above each other, whereby the garment is located on the putting-up-table 1* with the said edge sections against the stop 15 and with its upper part 19 separated by means of separating plates 17 and 18. For fetching the garment the gripping appliance 21 is turned to the position shown in figure 8, whereby the gripping bars 27 are somewhat separated so that these may grip over the edge section 13 which extends from the table 14. 3ust before the gripping appliance has reached the putting-up-table the stop 15 is turned downwards beneath the table, so that the edge section 13 is uncovered. At the same time as the gripping appliance has been moved against the putting-up-table, the knife blade 31 of the separating device 28 has also been moved into the space between the separating plates 17 and 18, so that when the gripping appliance has pinched the edge sections 13 between the gripping bars 27 and been displaced back to its starting point in the direction of the arrow 22, the knife blade 31 will keep the side parts of the garment ssparated as is shown in figure 2. During this horizontal movement the gripping appliance 21 at the same time is turned around is turning axle 42 to the transport position which is shown in figure 11 in which the garment will be hanging vertical like the knife blade 31, which also separates edge sections 13 of the garment 11, located above the gripping bars 2?, as schematically shown in figure 3. With the garment in this position the gripping appliance 21 is displaced along a transport track 43 in a direction towardsthe sewing machine 34, whereby the knife blade 31 will hit against the ploughtip 32, so that the side parts of the garment at one hand will be located on each side of the support 33 of the first transport device 23 and on the other hand the knife blade will be turned backwards at the movement of the gripping appliance in the direction of the arrow 24. The pressuring bars 37 are raised up to the point where the gripping appliance 21 has reached its front end position, in which the arms of the gripping appliance are turned outwards at the same time as the pressure bars are lowered in such a way that the pressure bars 37 may press the edge sections 13 against the conveyor belts 35 and 36. These are displaced in the direction towards the sewing machine 34 and transport the garment with the folded edge sections facing this. In order to lower the friction between the side parts of the garment and the support 33 this may possibly be perforated and its interior could be connected to a source of compressed air, so that the garment is lifted a little from the support 33. By means of a photocell (not shown) is detected for example the front edge of the garment when this has come to a certain position whereby the providing of the zipper may be synchronized, in such a way that both the garment and the zipper meet each other in an exact position just before both are fed to the press foot 40 of the sewing machine 34 and the sewing of the 2upper band may begin. The sewing machine 34 is conveniently in a known manner provided with double needles. A lining may be provided to the sewing machine via the conveyor 41 in the same way as the zipper, which lining then will be located above the zipper. The operator may locate a new garment on the putting-up-table 14 during the work of the sewing automatic machine and may in this way serve more than one automatic sewing machine.

Claims: CLAIMS 1. Method for automatically guiding of garment-s from at putting-up-table to a sewing machine for sewing of zippers, c h a r a c t e r i z e d t h e t e b y, that the edge sections (13) of the garment (11), along which edge sections a zipper is intended to be sewed on, are located essentially horizontally, edge to edge and above each other, that a gripping appliance (21) grips the garment along said edge sections, a distance inside and essentially parallel to the edges and turn the garment to a vertical hanging posit*+-on, that the side parts of the garment (11) located beneath and above the gripping appliance (21) are separated from each other by means of a separating device (28-) to a position essentially parallel to gripping bars (27) of -the gripping appliance. that the edge sections (13) of the garment (11-) are pressed by the gripping appliance t21) andor separate pressure bars (37) against a transport device (23) which guide the garment to a sewing machine (34), and that a zipper is provided from above to engagement against the edge sections (13) of the garment. which with the zipper is provided to the press foot (40) of the sewing machine for sewing. 2. Automatic sewing machine for accomplishing the method according to claim 1 and including a device for feeding of garments and sewing of a zipper to these by means of a sewing machine, c h a r act e r l z e d t h e r e b y, that a gripping appliance (21) is arranged and designed to grip edge parts (13) of garments (11) located on each other andby means of gripping bars (27), extending horizontally outside a putting-up-table (14), along which edge parts a zipper is intended to be sewed on, that the gripping appliance (21) is turnable from one position with its gripping bars (27) vertically to a horizontal position, in which the press-pinch betwen the gripping bars, is located in the feeding direction of the sewing machine (34), that a separating device (28) is arranged to separate the side parts of the garment located on both sides of the gripping bars from each other, that the gripping appliance (21) is displaceable in the feeding direction of the sewing machine above a first transport device (23) and designed to transfer the edge sections (13) of the garment (11) to this, that above the first transport device (23) is located a second transport device (38) by means of which zippers are transported to engagement up against with the edge sections (13) of the garment. 3. Automatic sewing machine according to claim 2, characterized thereby, that the separating device (28) includes a first dividing device (29) which is located at the gripping appliance (21) and which is designed as a turnable knife blade (31) intended to be located between the two side parts at fetching of the garment (11) , and of a second plough formed dividing device (32) located at the first transport device (23). 4. Automatic sewing machine according to the claims 2 or 3, characterized thereby, that the putting-up-table (14) is provided with a turnable stop (15) which in its turned aside position is arranged to uncover an edge section (13) of the garment (11). 5. Automatic sewing machine according to the claims 3 and 4, c h a r a c t e r i z e d t h e r e b y. that the putting-up-table (14) is provided with at least one, at some distance above the putting-up-table (14) located. separating plate (17) for separating of the front side parts of the garment, seen in the feeding direction of the sewing machine, and that the knife blade (31) of the separating device (28) is arranged to be inserted between the separating plate (17) and the side part of the garment located of the table (14) at the same time as the gripping appliance (21) fetches the garment. 6. Automatic sewing machine according to any of the above claims. C h a r a c t e r i z e d t h e r e b y. that the first conveyor (23) is provided with double, parallel and endless conveyor belts (35, 36) and pressure bars (37) mr the like which can be pressed against these betwen which pressure bars the gripping bars (27) of the gripping appliance (21) and the edge sections (13) folded by these are introducable inside and for delivery of said edge sections 7. Automatic sewing machine according to any of the above claims. characterized thereby, that the second conveyor (38) comprises a guiding chute (39) for the zippers inclined against the press foot (4Ct)' 6f the sewing machine and that a third conveyor (41) is arranged close to the second conveyor for feeding of a garment lining, if any. above the zipper.

Inventors: GUSTAVSSON, PERTTI O.
Applicants: AKAB OF SWEDEN AB
Application year: 1983
Main classification: D05B33
IPC codes: D05B35