EP0132486B1

EP0132486B1 - Method for automatic sewing of zippers and an automatic sewing machine for accomplishing the method

Info

Publication number: EP0132486B1
Application number: EP83850199A
Authority: EP
Inventors: Pertti O. Gustavsson
Original assignee: AKAB OF SWEDEN AB
Current assignee: AKAB OF SWEDEN AB
Priority date: 1983-07-21
Filing date: 1983-07-21
Publication date: 1987-11-25
Also published as: DE3374700D1; ATE31092T1; EP0132486A1

Abstract

A method to automatically transfer garments from a putting-up table (14) to a sewing machine (34) for automatically 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 DEG rotation, brings said edges (13) within the reach of the transport device (36) of the sewing machine (34) so as to sew zippers onto said edges (13).

Description

The present invention refers to a method for automatically guiding garments from a loading table to a sewing machine for sewing of zippers, and also an automatic sewing machine for accomplishing the method and which comprises a device for feeding of the garments and zippers to the presser foot of the sewing machine.

Background of the invention

Sewing of zippers is a relatively difficult operation and requires a long time of training. For 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 previously known automatic sewing machines for sewing of zippers, the zippers are often 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 are stretched differently, and therefore an even seam is very hard to acheive; 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.
In US-A-2.329.991 there is disclosed a sewing machine provided with guide means for the zipper inclined against the presser foot of the sewing machine, said guide means being arranged to guide the zipper from above onto the garment under a predetermined tension to the presser foot.

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 sections of the garment, along which edge sections a zipper is intended to be sewed on, are located essentially horizontally, edge to edge and above each other, that gripping bars of a gripping device grip the garment along said edge sections, a distance inside and essentially parallel to the edges, and turn the garment to a vertical hanging position, that the edge sections folded over the gripping bars are separated from each other by means of a separating device to a position essentially parallel to the gripping bars, that the separated edge sections are forwarded by the gripping device in a direction towards the sewing machine into a first transport device, that the separated edge sections are first pressed by the gripping bars and then by separate pressure bars against the first transport device which feeds the separated edge sections of the presser foot of the sewing machine, and that a zipper is fed from above into the edge sections just in front of the presser foot of the sewing machine for sewing.
To accomplish the method described above there is also proposed an automatic sewing machine which solves the problems mentioned above by means of, that it comprises a gripping device having gripping bars, which extend horizontally outside a loading table, that the gripping device is turnable from one position with its gripping bars being oriented vertically to another position with its gripping bars being oriented horizontally, in which latter position the press- pinch between the gripping bars is located in the feeding direction of the sewing machine, that a separating device is arranged to separate the garment edge sections folded over the gripping bars from each other, that the gripping device is displaceable in the feeding direction of the sewing machine above a first transport device and designed to transfer the edge sections onto the first transport device, that above the first transport device is located a second transport device for feeding a zipper onto the edge sections just in front of the presser foot of the sewing machine.

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 loading 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 4.
Figure 7 shows a cross section along the line VII-VII in figure 5.
Figure 8 shows a cross section analogous with figure 7 through the loading table with the gripping device 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 device 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 to be sewed, are located edge to edge on each other and located on a loading table 14, as is shown in figure 5. The loading 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 loading 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 device 21 is arranged at the side of the loading table 14, which gripping device is displaceable in the direction to and from the loading 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 device 21 consists of two transferring arms 26 which at their free ends are provided with gripping bars 27. The gripping device 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 two parts of which one dividing device 29 is located at the gripping device 21 and which comprises a knife blade 31 pivotable around an axle 30, while the other dividing device 32 comprises a plough- formed tip located at the support 33 of the first transport device 23. In the transport position of the gripping device 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 device 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 a 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 that the gripping bars 27 of the gripping device 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 presser 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 loading table 14 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 device 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. Just before the gripping device has reached the loading 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 device has been moved against the loading 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 device has pinched the edge section 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 separated as is shown in figure 2. During this horizontal movement the gripping device 21 at the same time is turned around its 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 27, as schematically shown in figure 3.
With the garment in this position the gripping device 21 is displaced along a transport track 43 in a direction towards the sewing machine 34, whereby the knife blade 31 will hit against the plough tip 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 device in the direction of the arrow 24. The pressuring bars 37 are raised up to the point where the gripping device 21 has reached its front end position, in which the arms of the gripping device 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) for example the front edge of the garment is detected 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 presser foot 40 of the sewing machine 34 and the sewing of the zipper 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 loading table 14 during the work of the sewing automatic machine and may in this way serve more than one automatic sewing machine.

Claims

1. Method for automatically guiding of garments from a loading table (14) to a sewing machine (34) for sewing of zippers, characterized in 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 gripping bars (27) of a gripping device (21) grip the garment along said edge sections, a distance inside and essentially parallel to the edges, and turn the garment to a vertical hanging position, that the edge sections (13) folded over the gripping bars (27) are separated from each other by means of a separating device (28, 31, 32) to a position essentially parallel to the gripping bars (27), that the separated edge sections (13) are forwarded by the gripping device (21, 27) in a direction towards the sewing machine (34) onto a first transport device (23), that the separated edge sections (13) are first pressed by the gripping bars (27) and then by separate pressure bars (37) against the first transport device (23) which feeds the separated edge sections (13) to the presser foot of the sewing machine (34), and that a zipper is fed from above into the edge sections (13) just in front of the presser foot (40) of the sewing machine (34) for sewing.

2. Automatic sewing machine for carrying out the method according to claim 1, comprising a device for feeding of garments and zippers to the presser foot of the sewing machine, characterized in that it comprises a gripping device (21) having gripping bars (27), which extend horizontally outside a loading table (14), that the gripping device (21) is turnable from one position with its gripping bars (27) being oriented vertically to another position with its gripping bars (27) being oriented horizontally, in which latter position the press- pinch between the gripping bars is located in the feeding direction of the sewing machine (34), that a separating device (28, 31, 32) is arranged to separate the garment's (11) edge sections (13) folded over the gripping bars (27) from each other, that the gripping device (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) onto the first transport device (23), that above the first transport device (23) is located a second transport device (38) for feeding a zipper onto the edge sections (13) just in front of the presserfoot (40) of the sewing machine (34).

3. Automatic sewing machine according to claim 2, characterized in that the separating device (28) includes a first dividing device (29) which is located at the gripping device (21) and which is designed as a turnable knife blade (31) intended to be located between the two edge sections (13) of the garment (11), and of second plough formed dividing device (32) located at the first transport device (23).

4. Automatic sewing machine according to claims 2 or 3, characterized in that the loading 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 claims 3 and 4, characterized in that the loading table (14) is provided with at least one separating plate (17), located at some distance above the loading table (14) for separating the front edge sections 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 one edge section of the garment at the same time as the gripping device (21) fetches the garment.

6. Automatic sewing machine according to anyone of the preceding claims, characterized in that the first transport device (23) is provided with double, parallel and endless conveyor belts (35, 36) and pressure bars (37) orthe like which can be pressed against the belts (35, 36) between which pressure bars (37) and belts (35, 36) the gripping bars (27) of the gripping device (21) are introduc- able for delivery of said edge sections (13).

7. Automatic sewing machine according to anyone of the preceding claims, characterized in that the second transport device (38) comprises a guiding chute (39) for the zippers inclined against the presser foot (40) of the sewing machine (34), and that a third transport device (41) is arranged close to the second transport device (38) for feeding of a garment lining above the zipper.