Workpiece Holder for Sewing Unit

Abstract

The work-piece holder (17) for the sewing unit has a holding frame (33), and a work piece (34) to be sewn is fixed to the holding frame (33). The holding frame (33) has a plurality of holding frame sections (36 to 39), which are articulated to each other by section joints (40). In this way, a work-piece holder is manufactured that enables loading even when the work-piece holder exceeds the work area accessible to the operator with respect to its loading dimensions.

Description

Technical Field

[0001] This patent application claims the priority of German Patent Application DE 10 2022 206 250.7, the content of which is incorporated herein by reference.

[0002] The present invention relates to a workpiece holder for a sewing unit. Furthermore, the present invention relates to a workpiece holder arrangement device having at least one such workpiece holder.

Background Art

[0003] Workpiece holders for sewing units are commercially known. Patent Document 1 discloses an automatic sewing machine. Patent Document 2 discloses a method of physically separating a fiber stack of a partial article from waste surrounding them in a continuous or partially continuous manner. Patent Document 3 discloses a sewing unit. Patent Document 4 discloses a sewing device having a movable fiber support. Patent Document 5 discloses a handling device for a material strip sewn by a sewing machine.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0005] An object of the present invention is to develop a workpiece holder that enables loading of a workpiece even when the workpiece holder exceeds the reachable work area of an operator with respect to its loading dimensions.

Means for Solving the Problems

[0006] According to the present invention, this object is achieved by a workpiece holder having the features described in claim 1.

[0007] According to the present invention, it has been recognized that the workpiece holder can be divided into a plurality of holding frame sections, and this does not cause an undesirable loss of stability of the workpiece holder in the sewing process. The workpiece can be fixed to the workpiece holder by frictional connection and / or fixing elements provided on the workpiece holder. As the fixing elements, tensile elements and / or clamp elements can be used. The workpiece holder has at least two holding frame sections. Depending on the design, the workpiece holder can also have three, four, five, or more holding frame sections. The workpiece holder usually has a maximum of 20 holding frame sections. The depth extension of the workpiece holder in a direction perpendicular to the articulation axis of the section joint can be at least 1 m, at least 1.5 m, at least 2 m, at least 2.5 m, and up to 3 m. Such a depth extension is generally up to 10 m at most. The maximum depth extension of one of the holding frame sections can be, for example, 800 mm, 750 mm, or 700 mm. Such a depth extension is generally greater than 400 mm. The pivot point of the section joint can be provided within or near the neutral line of the workpiece. The section joint can be part of the holding frame section, that is, part of the holding frame. Alternatively, the section joint can also be a component of the workpiece holder independent of the holding frame section. The workpiece fixed to the holding frame can be entirely surrounded by the holding frame. The holding frame sections constitute parts of the holding frame and can complement each other to form the holding frame as a whole.

[0008] The holding base according to claim 2 facilitates mounting the workpiece on the workpiece holder. The holding base usually has an opening at the location where the workpiece is sewn.

[0009] The frame rail according to claim 3 has been proven to be actually effective. The frame rail extends at least partially around the entire holding frame. The frame rail can extend around the entire holding frame. Each of the holding frame sections can constitute a part of the frame rail.

[0010] Due to the division according to claim 4, it is also possible to reinforce the workpiece holder with the frame rail at the location where the holding frame sections are adjacent to each other.

[0011] The guide body according to claim 5 facilitates guiding the movement of the workpiece holder while taking out the workpiece from the workpiece holder or attaching the workpiece to the workpiece holder.

[0012] A further object of the present invention is to provide a workpiece holder arrangement device that can use corresponding workpiece holders.

[0013] According to the present invention, this object is achieved by a workpiece holder arrangement device having the features according to claim 6.

[0014] The guide track of the workpiece holder arrangement device provides the possibility of changing direction for the purpose of unloading and loading even for a workpiece holder with a large depth extension. Thereby, each holding frame section to be unloaded or loaded is fully available without colliding with the holding frame sections that are not unloaded or loaded. At least one of the holding frame sections can be tilted by 90° or more, 150° or more, or nearly 180°, so that during the unloading or loading process, the holding frame sections are tilted relative to each other to form a U-shape. This saves space.

[0015] The design of the guide track according to claim 7 is stable, enabling good access to the holding frame section of the workpiece holder and allowing the workpiece to be mounted and / or removed.

[0016] Hereinafter, exemplary embodiments of the present invention will be described in more detail with reference to the drawings.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Figure 20

Figure 21

Figure 22

Figure 23

Figure 24

Figure 25

Figure 26

Figure 27

Figure 28

Figure 29

Figure 30

Figure 31

Figure 32

Figure 33

Figure 34

Figure 35

Figure 36

Figure 37

Figure 38

Figure 39

Embodiment for Carrying out the Invention

[0018] The portal (gate-shaped) sewing unit 1 shown in its entirety in FIGS. 1 and 2 is used to sew a workpiece (sewn object) in a working area with a width B greater than 1 m and 3 m in the illustrated embodiment. The sewing unit 1 includes a portal frame 2 having an upper bridge rail 3 and a lower bridge rail 4 (see also FIG. 10). Two opposing end-side portal supports 6 and 7 for forming a portal 5 for the workpiece are also attached to the portal frame 2.

[0019] Hereinafter, in order to facilitate understanding of the positional relationship, a rectangular coordinate system xyz is used. In FIG. 2, the x direction extends rightward along the extension line B in the width direction, the y direction is perpendicular to the drawing plane of FIG. 2 and extends into this figure. The z direction extends upward in FIG. 2.

[0020] The portal plane of the portal 5 extends parallel to the xz plane.

[0021] The upper bridge rail 3 serves to guide an upper sewing part 8 having an upper stitch former 9 in the form of a sewing needle for guiding an upper thread (not shown). Depending on the design of the portal sewing unit 1, a plurality of upper sewing parts 8, for example, two upper sewing parts, can also be used.

[0022] The lower bridge rail 4 serves to guide two lower sewing parts 10 and 11 (see also FIG. 12). The two lower sewing parts 10 and 11 each include lower stitch formers 12 and 13 in the form of loopers having a looper thread supply part in a bobbin-shaped looper thread supply container.

[0023] The loopers or lower threads of the lower sewing parts 10 and 11 can be composed of different colors and different thread qualities.

[0024] The sewing unit 1 is used to sew a two-thread stitch, for example, a two-thread lock stitch or a two-thread chain stitch.

[0025] At the end-side stop positions of the lower sewing parts 10, 11, it is possible to access the bobbins through the access windows 14, 15 of the unit housing 16 (see FIGS. 1 and 2).

[0026] During sewing, the workpiece holder 17 is at least partially placed on the working plate 18 of the working table 19 of the sewing unit 1 (see also FIG. 13). Two workpiece holders such as the workpiece holder 17 are stored in the middle for the purpose of mounting the workpiece and taking out the sewn workpiece using the multi-stage lifting table 20 of the sewing unit 1. The workpiece holder gripping device 21 including the gripping rails 22 is used to move each mounted workpiece holder 17 from the storage position shown in FIG. 1 to the sewing position (see also FIG. 13). The gripping rails 22 are linearly guided at both ends through the respective guide rails 23, 24. This linear guidance is driven via drive motors 25, 26. When the sewing area is small, it is also possible to use only one motor at the center of the gripping rail.

[0027] The two bridge rails 3, 4 and the gripping rails 22 extend parallel to the x-axis. The two guide rails 23, 24 extend parallel to the y-axis.

[0028] The multi-stage lifting table 20 has two table plates 27, 28, which are arranged stacked at a plurality of heights and are fixedly connected to each other for storing the respective workpiece holders 17. The upper table plate 27 of the two table plates provides an upper workpiece holder arrangement position, and the lower table plate 28 of the two table plates provides a lower workpiece holder arrangement position.

[0029] The table plates 27, 28 and the work plate 18 extend horizontally, that is, parallel to the xy plane.

[0030] The multi-stage lifting table 20 is a workpiece holder arrangement device. The two table plates 27, 28 are thus part of the placement table. Furthermore, this workpiece holder arrangement device is attached with a guide track 29 having two opposing guide plates or flanges 30, 31 each provided with a track groove 32.

[0031] During operation, the sewing unit 1 cooperates with a plurality of workpiece holders 17 that can be similarly configured. Therefore, it is sufficient to describe one of the workpiece holders 17 in more detail below.

[0032] FIG. 3 shows the workpiece holder 17, the upper table plate 27, and the two guide flanges 30, 31 of the guide track 29.

[0033] The workpiece holder 17 has a holding frame 33, to which a workpiece 34 to be sewn in the form of an intersecting strap 35 is fixed. The holding frame 33 has a plurality of holding frame sections 36, 37, 38, 39, a total of four in the illustrated embodiment (see also FIG. 4). In each case, the adjacent sections of the holding frame sections 36 to 39 are articulated to each other via section joints (partial joints) 40, 41, 42 (see, for example, FIG. 9). The articulation axes of these section joints 40 to 42 extend parallel to the x-axis.

[0034] Since the pivot points of the section joints 40 to 42 are within or near the neutral line of the workpiece 34, the workpiece 34 is neither stretched nor compressed unnecessarily while the holding frame sections 36 to 39 pivot relative to each other.

[0035] Alternative embodiments of the workpiece holder can also have a different number of such holding frame sections, specifically 2, 3, 5 or more such holding frame sections. The design of such a workpiece holder usually has a maximum of 20 such holding frame sections that are articulated to each other.

[0036] The depth extension of the workpiece holder 17 in the direction perpendicular to the joint axes of the section joints 40 - 42, i.e., the y - direction, is approximately 3 m in the illustrated embodiment and can reach at least 1 m, at least 1.5 m, at least 2 m, at least 2.5 m depending on the design of the workpiece holder 17 and can also be made larger than 3 m. The depth extension of the workpiece holder in the y - direction is usually a maximum of 10 m.

[0037] Figure 3 shows the starting position of the workpiece holder 17 with the previously loaded workpiece 34 that has been completely sewn by the sewing unit 1. Sewing is performed at the intersection 43 where the straps 35 extending in the lateral and longitudinal directions of the workpiece 34 intersect.

[0038] The workpiece holder 17 has a holding base 44 on which the workpiece 34 is placed. In particular, in the region of the intersection 43 to be sewn and, optionally, in further overlapping parts to be sewn, the holding base 44 has openings through which the workpiece 34 can be freely accessed from above and below.

[0039] Fixing elements 45 for fixing the workpiece 34 are attached to the holding base 44. These fixing elements 45 can be tension elements and / or clamp elements. Alternatively or additionally, the workpiece 34 can also be fixed to the holding base 44 by frictional connection.

[0040] A part of the holding frame sections 36 - 39 are corresponding holding base sections 441 - 444, which are articulated to each other via the section joints 40 - 42.

[0041] The retaining frame 33 has frame rails 46 which extend at least partially circumferentially and in the illustrated embodiment extend fully circumferentially to stabilize the retaining frame 33. The frame rail portions 461, 462 extending along the y-direction are both again divided into a plurality of rail portions which are articulated to each other by the section joints 40 - 42.

[0042] Each of the retaining frame sections 36 - 39 has at least one guide body 47 for cooperating in a guiding manner with the guide track 29 when the workpiece holder 17 moves along a guide direction F (±y-direction) perpendicular to the joint axes of the section joints 40 - 42. These guide bodies 47 project in the ±x-direction above the retaining frame sections 36 - 39 and are designed as guide pins which engage in the track runs 32 of the opposing guide flanges 30, 31.

[0043] In the illustrated embodiment of the workpiece holder 17, such guide bodies 47 are attached to the end of the workpiece holder 17 preceding in the -y direction and to the end of the workpiece holder 17 following in the +y direction, and in each case are attached at the height of the section joints 40 - 42.

[0044] Figures 5 to 8 show a sequence of instantaneous positions of the workpiece holder 17 while the workpiece holder 17 moves in the guide direction F starting from the starting position of Figure 3.

[0045] In the instantaneous position of Figure 5, the retaining frame section 36 preceding in the guide direction F is located between the guide flanges 30, 31 in the working area of the operating position for releasing and removing the workpiece 34 from the retaining frame section 36. In the instantaneous position of Figure 6, the retaining frame section 37 following next in the guide direction F is likewise in the working area. In the instantaneous position of Figure 7, this is the next retaining frame section 38, and in the instantaneous position of Figure 8, this is the last retaining frame section 39.

[0046] With the aid of the guide track 29, in accordance with the guided movement of the workpiece holder 17, the holding frame sections 36 to 39 are successively pivoted and redirected from horizontal to vertical in the manner of a sectional garage door.

[0047] The two guide holding frame sections 36 and 37 are redirected by approximately 180° when the workpiece holder 17 is in the end position of FIGS. 8 and 9. In this end position, the holding frame section 39 is accessible to the operator in the working area and is arranged approximately horizontally in this end position. The holding frame sections 36 to 38 are inclined by more than 45° during the redirection operation starting from the starting position of FIG. 3, i.e., the horizontal arrangement posture of the workpiece holder 17 on the table plate 27. The two holding frame sections 36, 37 are inclined by more than 90°, and further by more than 150°.

[0048] In the sequence of FIGS. 5 to 8, the operator has access to all the holding frame sections 36 to 39 to remove the workpiece 34. In the reverse sequence, loading can be carried out on the holding frame sections 39 (position in FIG. 8), 38 (position in FIG. 7), 37 (position in FIG. 6), and 36 (position in FIG. 5). In this case, the movement of the workpiece holder 17 on the guide track 29 is carried out in a direction opposite to the guide direction F.

[0049] The movement along the conveying direction F and the movement in the opposite direction can be carried out by the workpiece holder drive device and / or manually.

[0050] The portal frame 2 of the sewing unit 1 with the upper and lower sewing parts 8, 10, 11 will be described in detail below with reference to FIGS. 10 to 12.

[0051] The upper drive device 48 serves to move the upper sewing unit 8 along the upper bridge rail 3, i.e., in the + / -x direction. The lower drive device 49, independently of the upper drive device 48, serves to move the lower sewing units 10, 11 along the lower bridge rail 4, i.e., again in the + / -x direction. The drive devices 48, 49 and further drive devices of the sewing unit 1 are controlled via a central control unit housed in a control cabinet 50 (see FIG. 1).

[0052] The upper drive device 48 and the lower drive device 49 are selectively controlled such that the upper workpiece part 8 cooperates with one of the two lower sewing units, for example the lower sewing unit 10, or the upper sewing unit 8 cooperates with the other of the two lower sewing units, for example the lower sewing unit 11, in order to form stitches in the workpiece 34.

[0053] In the illustrated embodiment, the lower drive device 49 is designed with exactly one drive source. Couplings of the respective lower sewing units 10, 11, not shown in detail in the drawing, are used to separate one of each of the lower workpiece parts 10, 11 from the drive train of the lower drive device 49 designed as a chain or belt.

[0054] Alternatively, the lower drive device 49 can be designed with two independent drive sources, one for each of the two lower sewing units 10, 11.

[0055] By means of the lower drive device 49, the lower sewing units 10, 11 can move to their stop positions independently of each other, at which positions the respective looper thread supply containers can be exchanged for replacement looper thread supply containers, in particular the bobbins, via the access windows 14, 15.

[0056] This exchange is carried out in an automated manner without manual intervention. Alternatively, the exchange can also be carried out manually or semi-automatically.

[0057] The upper drive device 48 and / or the lower drive device 49 can be provided with a rack and / or a transmission gear as a transmission member. Each of the lower sewing parts 10, 11 can have its own transmission gear.

[0058] FIG. 10 shows the lower sewing part 10 in the left stop position accessible through the access window 14. In FIG. 10, the lower sewing part 11 is shown in the right stop position accessible through the access window 15. In FIG. 10, the upper sewing part 8 is shown in the right stop position assigned to the lower sewing part 11.

[0059] FIG. 11 shows a state where the upper sewing part 8 and the lower sewing part 11 are in the sewing position. At this position, these two sewing parts 8, 11 can cooperate to form stitches on the workpiece 34. At this sewing position, synchronization is performed between the upper sewing part 8 and the lower sewing part (in this case, the lower sewing part 11) that is currently cooperating with it to form stitches. This synchronization is performed by the control unit. The driving displacement direction of the drive devices 48, 49, that is, the three-dimensional synchronization accuracy along the x-axis, is better than 0.3 mm. This synchronization accuracy can be in the range of 0.1 mm. Since the needle and the looper need to be connected to separate drive devices, they need to be synchronized.

[0060] At the position of FIG. 11, the lower sewing part 10 that is not currently sewing is in the left stop position. In the case of the lower sewing part 10, while the upper sewing part 8 is performing a sewing operation with the lower sewing part 11, the looper thread supply container can be exchanged at the position of FIG. 11.

[0061] After the exchange, the lower sewing part 10 becomes operable. When the looper thread of the currently sewing lower sewing part 11 starts to run out, under the control of the control unit, the sewing process temporarily stops, and the lower sewing part 11 that has been sewing until then is moved to the right stop position in FIG. 12 by the lower driving device 49. Further, due to the interaction between the upper driving device 48 and the lower driving device 49, synchronization between the upper sewing part 8 and the newly filled lower sewing part 10 is performed. Thereafter, the sewing unit 1 can continue sewing by the cooperation of the upper sewing part 8 and the lower sewing 10. During this time, in the lower sewing part 11, the replacement of the looper thread supply container is performed, and the lower sewing part 11 is accessible through the access window 15.

[0062] When a new bobbin is loaded, the stopped lower sewing part moves close to the sewing lower sewing part. In this way, after the bobbin becomes empty, the sewing lower sewing part can be separated from the upper sewing part, and the stopped lower sewing part can be immediately connected to start synchronization. Thus, a considerable amount of time can be saved.

[0063] The multi-stage lifting table 20 of the sewing unit 1 will be described in more detail below with reference to FIGS. 13 to 39.

[0064] FIG. 13 shows the multi-stage lifting table 20 together with the portal frame 2 and the work table 19 which are the main components of the sewing unit 1. The lifting table frame 51 for supporting the multi-stage lifting table 20 on the ground is omitted from FIG. 13 onwards.

[0065] FIG. 13 shows a multi-stage lifting table 20 loaded with two workpiece holders 17. Hereinafter, the upper workpiece holder 17 will also be referred to as the workpiece holder 171, and the initially lower workpiece holder 17 will also be referred to as the workpiece holder 172 (see, for example, FIG. 16). Of the two workpiece holders 171, the upper one is at the upper workpiece holder placement position on the upper table plate 27 of the multi-stage lifting table 20. The second workpiece holder 172 is at the lower workpiece holder placement position on the lower table plate 28.

[0066] The two table plates 27 and 28 are fixedly connected to each other via a total of six vertical support columns 521 to 526 and a support plate 53. The support plate 53 is vertically arranged between the table plates 27 and 28 and between the two support columns 523 and 524 that are at the position farthest from the portal frame 2. The support columns 521, 523, 524, and 526 are located at the four corners of the table plates 27 and 28 arranged vertically in alignment. The support columns 522 and 525 are located in the middle between one pair of support columns 521 and 523 and between the other pair of support columns 524 and 526.

[0067] The multi-stage lifting table 20 has two pairs of roller conveyors 54 and 55. The rollers of the roller conveyors of the pairs of roller conveyors 54 and 55 can rotate freely. Of these two pairs of roller conveyors, the upper pair of roller conveyors 54 has two opposing roller conveyors 541 and 542 that are located at the same height in the z direction and spaced apart from each other in the x direction. The lower pair of roller conveyors 55 also has two roller conveyors 551 and 552 that are located at the same height in the z direction and spaced apart from each other in the x direction. The roller conveyor 541 is above the roller conveyor 551 in the z direction. The roller conveyor 542 is above the roller conveyor 552 in the z direction. Only the roller conveyor 551 facing the observer is shown in either case of the two roller conveyors 551 and 552.

[0068] The roller conveyors of the roller conveyor pair 54 and 55 extend longitudinally along the y direction respectively. The roller conveyors 541, 542, 551, and 552 are each interrupted in the y direction. Due to this interruption, a space for the support column 522 and a space for the support column 525 are formed respectively.

[0069] At the momentary positions from FIG. 13 to FIG. 15, the upper table plate 27 is between the two upper roller conveyors 541 and 542 of the upper roller conveyor pair 54, and the lower table plate 28 is between the two roller conveyors 551 and 552 of the lower roller conveyor pair 55. The roller conveyors 541, 542, 551, and 552 can be moved between the stored roller conveyor position (see FIG. 17) and the extended roller conveyor position (see FIG. 18) using the roller conveyor lifting and lowering drive device 56 (see FIG. 2). At the stored roller conveyor position, the x-direction distance between one roller conveyor 541, 542 and the other roller conveyor 551, 552 is shorter than the x-direction extension of the workpiece holder 17. At the extended roller conveyor position in FIG. 18, this x-direction distance between one roller conveyor 541, 542 and the other roller conveyor 551, 552 is longer than the x-direction extension of the workpiece holder 17.

[0070] Furthermore, the multi-stage lifting and lowering table 20 includes a plate lifting and lowering drive device 57 (see FIG. 2) for moving the table plates 27 and 28 up and down with respect to the lifting and lowering table frame 51.

[0071] The two roller conveyor pairs 54 and 55 can be moved between, for example, the lowered plate position shown in FIG. 16 and, for example, the plate position raised by lifting in the z direction as compared to the lowered plate position shown in FIG. 31 via the roller conveyor lifting and lowering drive device 56.

[0072] At the lowered plate position, the roller conveyors of the roller conveyor pairs 54 and 55 are arranged on both sides of the table plates 27 and 28 respectively assigned to these roller conveyor pairs 54 and 55. By this arrangement, the upper roller planes 58 and 59 of the respective roller conveyor pairs 54 and 55 are located below the table plate planes 60 and 61 of the assigned table plates 27 and 28.

[0073] At the raised plate position (see, for example, FIG. 31), the upper roller planes 58 and 59 of the respective roller conveyor pairs 54 and 55 are located above the table plate planes 60 and 61 of the assigned table plates 27 and 28. There is a z-direction distance d respectively between one of the roller planes 58 and 59 and the table plate planes 60 and 61 of the other assigned table plates 27 and 28 (see FIG. 31). At this raised plate position, the roller conveyors are simultaneously in the storage position (see FIG. 17), and the two roller conveyors of each roller conveyor pair 54 and 55 are separated from each other by an x-direction distance, and on the condition that the x-direction distance is smaller than the x-direction extension of the workpiece holder 17, the roller guide for moving the workpiece holder 17 from or to the respective storage positions of the table plates 27 and 28 is possible.

[0074] By the plate lifting drive device 57, the respective table plate planes 60 and 61 of the selected table plates 27 and 28 can be moved to the lifted position aligned with the work plate plane 62 of the work plate 18 of the work table 19 (see, for example, FIG. 20).

[0075] One of the plate lifting drive devices 57 and the other roller conveyor lifting drive device 56 can be formed as a linear drive device or a lifting cylinder.

[0076] As already described in connection with FIGS. 3 to 9, the upper workpiece holder arrangement position can be used for loading the workpiece 34 to be sewn on the workpiece holder 17 or removing the sewn workpiece 34 from the workpiece holder 17.

[0077] Furthermore, the roller conveyor pairs 54 and 55 can be displaced to a workpiece holder receiving position that is further elevated compared to the elevated plate position by being elevated along the z-direction with respect to the table plates 27 and 28 by the roller conveyor elevating drive device 56. This workpiece holder receiving position is shown, for example, in FIG. 26. Each upper workpiece holder (in the case of the position in FIG. 26, the workpiece holder 172) is then received at a position above the upper workpiece holder arrangement position that is spaced apart from the upper table plate 27 by a distance A in the z-direction. This z-direction distance A is greater than the z-direction extension of the workpiece holder 17.

[0078] The lower roller conveyor pair 55 can be moved in the positive z-direction by the roller conveyor elevating drive device 56 to such an extent that its lower roller plane 59 is positioned above the upper table plate plane 60 of the upper table plate 27. This instantaneous position in the z-direction is shown in FIG. 28. The lower roller conveyor pair 55 can then guide one of the workpiece holders 17 (in the example shown in FIG. 28, the workpiece holder 171) on its rollers in order to move it onto or away from the upper table plate 27.

[0079] In order to move the workpiece holders 171 and 172 between the storage position and the working position on the working plate 18 of the work table 19, a workpiece holder gripping device 21 is used. It is shown, for example, in the neutral position outside the sewing work area in FIG. 1. In the gripping position not shown in the figure, the gripping tool of the workpiece holder gripping device 21 designed in the form of gripping pins 63, 64 (see FIG. 13) is aligned with the working plate 18 in the z direction respectively. In the multi-stage lifting table 20, it grips the end of the workpiece holder 17 at the storage position of one of the two table plates 27, 28 and transfers it to the workpiece holder position. This workpiece holder 17 is respectively aligned with the working plate 18 in the z direction and is in the storage position on one of the two table plates 27, 28 in the multi-stage lifting table 20, and is transferred to the workpiece holder position. This is done by the gripping pins 63, 64 engaging with the complementary bushes of the workpiece holder 17 to be gripped. The gripping pins 63, 64 can be pneumatically moved into their respective complementary bushes.

[0080] Hereinafter, the operation cycle of the sewing unit 1, particularly the multi-stage lifting table 20 and the workpiece holder gripping device 21, will be described with reference to FIGS. 19 to 39.

[0081] FIG. 19 shows the starting position of the multi-stage lifting table 20. The upper workpiece holder 171 is in the upper storage position on the table plate 27, and the lower workpiece holder 172 is in the lower storage position on the table plate 28. The roller conveyor pairs 54, 55 are shown in the lowered plate position. The lower table plate plane 61 is aligned with the working plate plane 62.

[0082] The sewing of the upper workpiece holder 171 is completed. The lower workpiece holder 172 is mounted for sewing.

[0083] Figure 20 shows the following working steps. The workpiece holder gripping device 21 grips the end of the workpiece holder 172 and pulls it in the positive y direction through the portal 5 of the portal sewing unit 1. The control device synchronizes the looper drive devices 25, 26 with the workpiece drive devices 48, 49, so that the workpiece 34 is sewn on the workpiece holder 172.

[0084] At the position of Figure 20, the workpiece holder 171 is removed and attached in conjunction with the guide track 29 as described above.

[0085] Figure 21 shows the instantaneous position after the process of sewing the workpiece 34 on the workpiece holder 172 is completed. At this time, the workpiece holder 172 is completely placed on the worktable 19 so as not to overlap with the multi-stage lifting table 20 in the y direction.

[0086] At the instantaneous position of Figure 21, at the upper workpiece holder placement position, the workpiece 34 to be sewn is attached to the workpiece holder 171.

[0087] At the instantaneous position (the first change position) of Figure 22, the multi-stage lifting table 22 having the table plates 27, 28 and the related roller conveyor pairs 54, 55 is moved in the negative z direction by the plate lifting drive device 57, and the entire upper workpiece holder 171 is moved to a change position located on the upper table plate 27 below the work plate plane 62.

[0088] Figure 23 shows the instantaneous position (the position of Figure 18) where the roller conveyor pairs 54, 55 are extended so that the x-direction distance between them increases, as compared with the position of Figure 22. This is performed using the roller conveyor lifting drive device 56.

[0089] Figure 24 shows a situation where the roller conveyor pair is moved in the positive z-direction with respect to the two table plates 27 and 28 using the roller conveyor lifting drive device 56 and is at the workpiece holder receiving position. Therefore, the upper roller conveyor pair 54 passes through the z-plane of the workpiece holder 171 at the upper workpiece holder placement position. The roller conveyors of the roller conveyor pairs 54 and 55 continue to extend at the position shown in Figure 24.

[0090] Figure 25 shows the instantaneous position achieved by the stored roller conveyors of the roller conveyor pairs 54 and 55. The upper roller plane 58 is above the workpiece holder 171 at the upper workpiece holder receiving position and is aligned with the work plate plane 62.

[0091] Figure 26 shows the instantaneous position where the sewn workpiece holder 172 is pushed in the negative y-direction onto the roller conveyor of the upper roller conveyor pair 54 by the workpiece holder gripping device 21.

[0092] Figure 27 shows the next situation where, after the workpiece holder 172 is completely received at the workpiece holder receiving position, the entire multi-stage lifting table 20 is moved in the positive z-direction by the plate lifting drive device 57 and the upper table plate plane 60 is aligned with the work plate plane 62.

[0093] Compared with the first changed position in Figure 22, the multi-stage lifting table 20 is at the second changed position in Figure 27.

[0094] Figure 28 shows the next instantaneous position where the roller conveyor pairs 54 and 55 are further moved in the positive z-direction with respect to the table plates 27 and 28 by the roller conveyor lifting drive device 56 compared to the position in Figure 27. Since the lower roller plane 59 is located slightly above the upper table plate plane 60, the workpiece holder 171 at the upper workpiece holder placement position is located on the roller conveyor of the lower roller conveyor pair 55.

[0095] Figure 29 shows the next instantaneous position where the workpiece holder 171 is drawn onto the work plate 18 of the work table 19 through the portal 5 after being gripped by the workpiece holder gripping device 21. Here, or at a later time as described below, this loaded workpiece holder 171 can be sewn as described above in relation to the workpiece holder 172 at the instantaneous position in Figure 20. The other workpiece holder 172 is still at the workpiece holder receiving position on the roller conveyor of the roller conveyor pair 54.

[0096] Figure 30 shows the next instantaneous position where the entire multi-stage lifting table 20 equipped with the plate lifting drive device 57 has further moved in the positive z direction. At this position, the lower table plate plane 61 is aligned with the work plate plane 62.

[0097] The movement to this instantaneous position in Figure 30 is performed after the workpiece holder 171 is completely placed on the work table 19 and no longer overlaps with the multi-stage lifting table 20 in the y direction.

[0098] Figure 31 shows the next instantaneous position where the two roller conveyor pairs 54, 55 have been lowered to the ascending plate position. In each case, there is a z-direction distance d between one of the two roller planes 58, 59 and the two table plate planes 60, 61. The lower table plate plane 61 remains aligned with the work plate plane 62.

[0099] Figure 32 shows the next instantaneous position where the sewn workpiece 34 can be removed from the workpiece holder 172.

[0100] Figure 35 shows, on the one hand, the instantaneous position where the workpiece holder 171 can be sewn when sewing is not being performed at the instantaneous position in Figure 29, corresponding to the description given above with reference to Figure 20. On the other hand, it shows the instantaneous position where the workpiece holder 172 is loaded, as described above with reference to Figures 3 and later. The lower table plate plane 61 remains aligned with the work plate plane 62.

[0101] Figure 33 shows the moment when the workpiece holder 172 that has not yet been lowered is fully pushed out onto the roller conveyor of the upper roller conveyor pair 54 and is at a position of distance d above the upper table plate 27.

[0102] Figure 34 shows the next moment when the two roller conveyor pairs 54 and 55 move in the negative z direction to the lowered plate position, and the workpiece holder 172 is placed on the upper table plate 27.

[0103] Figure 36 shows the next moment when the workpiece holder 171 with the sewing completed is placed on the lower table plate 28 using the workpiece holder gripping device 21.

[0104] Figure 37 shows the next moment when the workpiece holder 171 is pulled out from the lower table plate 28 onto the work table 19 using the workpiece holder gripping device 21 for sewing.

[0105] Figure 38 shows the moment when the workpiece holder 171 is completely sewn by the sewing unit 1 and placed on the work table 19 in the y direction without being aligned with the multi-stage lifting table 20.

[0106] The moment in Figure 39 corresponds to the position in Figure 21. Only the workpiece holders 171 and 172 are exchanged, but the other sewing and loading situations, and the positions of the workpiece holders 171 and 172 relative to the sewing unit 1 are the same. The cycle from Figure 21 to Figure 39 can be continuously repeated.

[0107] When the number of looper threads in the lower sewing parts 10 or 11 currently in use begins to decrease, as described above in connection with FIGS. 10 to 12, this looper supply is replaced. Compared with the replacement time of the looper supply, the sewing process during the replacement of the lower sewing parts 10 and 11 is interrupted only for a clearly shorter period, such as 25%, 20%, 10%, or less of the replacement time.

Explanation of Signs

[0108] 1 Portal sewing unit 2 Portal frame 3 Upper bridge rail 4 Lower bridge rail 5 Portal 6, 7 Portal support 8 Upper sewing part 9 Upper stitch former 10, 11 Lower sewing part 12, 13 Lower stitch former 14, 15 Access window 16 Unit housing 17 Workpiece holder 18 Work plate 19 Work table 20 Multi-stage lifting table 21 Workpiece holder gripping device 22 Gripping rail 23, 24 Guide rail 25, 26 Drive motor 27, 28 Table plate 29 Guide track 30, 31 Guide flange 32 Track runner 33 Holding frame 34 Workpiece 35 Strap 36 - 39 Holding frame section 40 - 42 Section joint 43 Intersection 44 Holding base 45 Fixed element 46 Frame Rail 47 Guide Body 48 Upper Driving Device 49 Lower Driving Device 50 Control Cabinet 51 Lifting Table Frame 53 Support Plate 54 Upper Roller Conveyor Pair 55 Lower Roller Conveyor Pair 56 Roller Conveyor Lifting Driving Device 57 Plate Lifting Driving Device 58 Upper Roller Plane 59 Lower Roller Plane 60 Upper Table Plate Plane 61 Lower Table Plate Plane 62 Working Plate Plane 63, 64 Gripping Pins 441 - 444 Holding Base Sections 461 - 462 Frame Rail Parts 521 - 526 Support Struts 541, 542, 551, 552 Roller Conveyors

Claims

1. A workpiece holder (17) for a sewing unit (1), having a holding frame (33) to which a workpiece (34) to be sewn is fixed, wherein the holding frame (33) comprises a plurality of holding frame sections (36 - 39) articulated to each other by section joints (40 - 42), the workpiece holder.

2. The workpiece holder according to claim 1, wherein the holding frame (33) comprises a holding base (44) on which the workpiece (34) is placed, and the holding base (44) comprises a plurality of holding base sections (44) articulated to each other.

3. The workpiece holder according to claim 1 or 2, wherein the holding frame (33) comprises a frame rail (46) at least partially surrounding the periphery thereof for stabilizing the holding frame (33).

4. The workpiece holder according to claim 3, wherein at least a part of the frame rail (46) is divided into a plurality of rail parts articulated to each other.

5. Each of the holding frame sections (36 - 39) has at least one guide body (47), and the guide body (47) cooperates with a guide track (29) in a guiding manner during the movement of the workpiece holder (17) along a guide direction (F) orthogonal to the joint axis of the section joints (40 - 42), the workpiece holder according to any one of claims 1 to 4.

6. A workpiece holder arrangement device (20), having at least one workpiece holder (17) according to any one of claims 1 to 5, having an arrangement table (27), having a guide track (29) for guiding the direction-changing operation of the workpiece holder (17) along a guide direction (F) orthogonal to the joint axis of the section joints (40 - 42) of the workpiece holder (17), wherein during the direction-changing operation, starting from the arrangement posture, at least one of the holding frame sections (36 - 39) is inclined by 45° or more, the workpiece holder arrangement device (20).

7. The guide track (29) according to claim 6, characterized in that it comprises two opposing guide plates (30, 31) each having a track run (32), between which the workpiece holder (17) is guided.

Images