JP7092458B2 - How to manufacture stitched skin material - Google Patents

Description

The present invention relates to a method for manufacturing a skin material with a decorative stitch that forms a decorative stitch on the skin material.

Patent Document 1 discloses a method of forming decorative stitches on a skin material formed into a three-dimensional shape by a sewing machine (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2011-46311 (paragraph [0028], FIG. 3)

However, in the method for manufacturing a skin material with decorative stitches shown in Patent Document 1, since the decorative stitches are formed by human hands, there is a problem that the seams are liable to be uneven or twisted, and defective products are generated. rice field. In particular, when the skin material is shaped into a three-dimensional shape before the decorative stitch is formed, the problem of defective products is remarkable.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for manufacturing a skin material with decorative stitches, which can reduce the occurrence of defective products.

The first aspect of the invention made in view of the above circumstances is a method for manufacturing a skin material with decorative stitches for forming decorative stitches on a skin material shaped into a three-dimensional shape, and the robot is provided with the skin material. This is a method for manufacturing a skin material with decorative stitches, wherein the robot moves the skin material to a receiving portion receiving the skin material in an automatic sewing machine and moves the skin material to a predetermined pattern, and the automatic sewing machine forms the decorative stitch.

A second aspect of the present invention includes, in the automatic sewing machine, a cutting means for cutting the needle thread connected to the skin material after forming the decorative stitch, and a thread breakage detecting means for detecting the breakage of the needle thread. , The needle thread is cut by the cutting means, the thread breakage detecting means detects that the needle thread has been cut, and then the robot or a robot different from the robot is used. The method for manufacturing a skin material with a decorative stitch according to the first aspect, wherein the next skin material is applied to the receiving portion of the automatic sewing machine to form the decorative stitch.

A third aspect of the present invention is to detect, in the thread breakage detecting means, a rotary wheel around which the needle thread is wound between the thread feeding device for feeding the needle thread and the skin material, and the rotation of the rotary wheel. The method for manufacturing a skin material with decorative stitches according to the second aspect, wherein the rotation detecting means is provided.

A fourth aspect of the present invention includes, in the automatic sewing machine, a holding means for holding the needle thread connected to the skin material after forming the decorative stitch, and a cutting means for cutting the needle thread connected to the skin material. Is provided, after the decorative stitch is formed, the skin material is moved by the robot, the needle thread connected to the skin material is held by the holding means, and then the needle thread is held by the cutting means. The method for producing a skin material with decorative stitches according to any one of the first to third aspects.

A fifth aspect of the invention is to continue holding the needle thread by the holding means until the next skin material is addressed to the receiving portion of the automatic sewing machine, and after starting sewing of the decorative stitch, the holding. The method for manufacturing a skin material with decorative stitches according to a fourth aspect, which releases the holding of the needle thread by means.

A sixth aspect of the present invention is any one of the first to fifth aspects, wherein the skin material has a laminated structure having an outer layer made of an elastomer and a lining layer made of a foamed resin. It is a method for manufacturing a skin material with decorative stitches according to the aspect.

[First and sixth aspects of the invention]
In the first aspect of the invention, since the decorative stitches are formed on the skin material by the robot and the automatic sewing machine, the seams are less likely to be uneven or twisted as compared with the case where the decorative stitches are formed by human hands. It is possible to reduce the occurrence of defective products.

It is preferable that the skin material has a laminated structure having an outer material layer made of an elastomer and a lining layer made of a foamed resin from the viewpoint of shape retention of the skin material (sixth aspect of the invention). ).

[Second and third aspects of the invention]
In the second aspect of the invention, after the cutting of the needle thread is detected by the thread breakage detecting means, the next skin material is addressed to the receiving portion of the automatic sewing machine to form a decorative stitch, so that the needle thread is not formed. It is possible to prevent the formation of decorative stitches on the next skin material as it is cut. Further, even when an abnormality occurs in which the needle thread is broken during sewing, the abnormality can be detected.

The thread breakage detecting means may be configured to directly detect the movement of the needle thread, or may be configured to indirectly detect the movement of the needle thread. Examples of the latter include a rotating wheel in which the needle thread is wound between the thread feeding device for feeding the needle thread and the skin material, and a rotation detecting means for detecting the rotation of the rotating wheel, as in the third aspect of the invention. , A configuration comprising. In the third aspect of the invention, the detection accuracy is improved as compared with the case where the movement of the needle thread itself is detected.

[Fourth aspect of the invention]
In the fourth aspect of the invention, since the needle thread is held by the holding means and then the needle thread is cut, the cutting of the needle thread is stabilized.

[Fifth aspect of the invention]
In the fifth aspect of the invention, since the holding of the needle thread by the holding means is released after the sewing of the decorative stitch is started, the end portion of the needle thread at the start of sewing is entangled with the needle thread and the bobbin thread to form a lump. So-called bird's nest prevention is planned.

Perspective view of an instrument panel using a skin material with decorative stitches according to an embodiment of the present invention. (A) Partially broken perspective view of the instrument panel, (B) side sectional view Schematic block diagram of automatic sewing system Block diagram of automated sewing system Front view of automatic sewing machine Schematic block diagram of the thread feeder Plane cross section of the pulley Front view of Kamadai and work guide (A) Schematic configuration of the thread cutting device, (B) Clamp and guide member viewed from the rear side. (A) front view and (B) side sectional view of the thread breakage sensor when the rotation sensor is off. (A) front view and (B) side sectional view of the thread breakage sensor when the rotation sensor is on. Front view of thread breakage sensor according to another embodiment A view of the clamp and the guide member according to another embodiment as viewed from the rear side.

As shown in FIG. 1, the skin material 10 with decorative stitches of the present embodiment is used for the instrument panel 111 of the vehicle 110. As shown in FIG. 2A, the skin material 10 with decorative stitches is fixed to the surface of the base material 112 facing the front side to form the design surface of the instrument panel 111. The skin material 10 with decorative stitches is formed by forming decorative stitches S on the skin material 11.

As shown in FIG. 2A, the base material 112 has a substantially L-shape in the side view, and the skin material 11 also has a substantially L-shape in the side view corresponding to the shape of the base material 112. The decorative stitch S is formed at an L-shaped corner portion of the skin material 11. Specifically, the skin material 11 has a ceiling wall 11T extending in the left-right direction and a front wall 11F hanging from the front end of the ceiling wall 11T, and a decorative stitch S is formed on the front end portion of the ceiling wall 11T. Has been done. The ceiling wall 11T is curved so that the upper side is convex. Further, the front wall 11F is provided with an extension portion 11S that protrudes toward the front side in the shape of a hinamatsuri as it goes downward.

As shown in FIG. 2B, the base material 112 is made of a synthetic resin. The skin material 11 has a laminated structure in which the backing layer 13 is laminated on the back side of the outer layer 12. The outer layer 12 is composed of a thermoplastic elastomer (for example, TPO). The lining layer 13 is made of a foamed resin (for example, PP foam or PE foam). As a result, the shape retention of the skin material 11 is stabilized.

The decorative stitched skin material 10 is obtained by forming the decorative stitch S on the skin material 11 shaped into a three-dimensional shape corresponding to the base material 112. FIG. 3 shows an automated sewing system 100 for forming decorative stitches S. In the automatic sewing system 100, the robot 90 takes out the skin material 11 from the work stand 102 and addresses it to the kettle stand 32 which is a receiving portion for receiving the skin material 11 in the automatic sewing machine 20. Then, the robot 90 moves the skin material 11, and the automatic sewing machine 20 forms the decorative stitch S on the skin material 11. As shown in FIG. 4, in the automatic sewing system 100, the robot 90 and the automatic sewing machine 20 are controlled by the main control unit 101.

As shown in FIGS. 3 and 4, the robot 90 is controlled by the robot control unit 90A according to a control signal from the main control unit 101. The robot 90 is a general-purpose product of a vertical articulated type, and detects the positions of an arm 91 composed of a plurality of arm components 91A, an arm drive unit 92 for driving each arm component 91A, and each arm component 91A. It has a position sensor 93 for the robot hand 94 and a robot hand 94 attached to the tip of the arm 91. A suction pad (not shown) for holding the skin material 11 is fixed to the robot hand 94.

As shown in FIG. 4, the automatic sewing machine 20 is controlled by the sewing machine control unit 20A according to a control signal from the main control unit 101. As shown in FIG. 5, the automatic sewing machine 20 has a needle drive mechanism 31K that drives the sewing needle 31 up and down, a hook mechanism 32K that forms a seam in cooperation with the needle drive mechanism 31K, and a skin material on the sewing machine frame 21. A feed mechanism 33 or the like that conveys 11 along the feed direction X is attached.

The sewing machine frame 21 includes a sewing machine bed 22 that forms the lower part of the sewing machine frame 21 and extends in the left-right direction Y, a sewing machine arm 23 that forms the upper part of the sewing machine frame 21 and faces the sewing machine bed 22 from above, and a sewing machine bed 22. It is provided with an arm support portion 24 that is erected at one end and communicates with the sewing machine arm 23, and is formed in a substantially U-shape in front view as a whole. The left-right direction Y in which the sewing machine bed 22 and the sewing machine arm 23 extend is orthogonal to the feed direction X in which the automatic sewing machine 20 feeds the sewing machine.

The needle drive mechanism 31K has a rotary weight (not shown) fixed to an upper shaft extending in the left-right direction Y in the sewing machine arm 23, and a crank rod whose upper end is rotatably connected to an eccentric portion of the rotary weight (FIG. (Not shown), a needle rod 31B rotatably connected to the lower end of the crank rod, and a sewing needle 31 supported by the lower end of the needle rod 31B. Then, when the upper shaft rotates under the driving force of the sewing machine motor 37 (see FIG. 4), the rotation is converted into a reciprocating motion in the vertical direction Z via the rotary weight and the crank rod, and the needle rod 31B and the sewing needle 31 are used. Reciprocates in the vertical direction Z.

The automatic sewing machine 20 is a post-type sewing machine, and is provided with a hook mechanism 32K on a post 25 erected upward from the sewing machine bed 22. The hook mechanism 32K includes a hook base 32 fixed to the upper end of the post 25, a hook shaft extending in the vertical direction Z in the post 25 (not shown), and a hook shaft supported by the hook shaft in the hook base 32. It is equipped with a horizontal hook (not shown) that rotates around. Then, when the lower shaft extending in the left-right direction Y in the sewing machine bed 22 rotates together with the above-mentioned upper shaft, the kettle shaft rotates via a gear (not shown), and the horizontal kettle rotates. As a result, the horizontal hook and the sewing needle 31 cooperate to form a seam.

Further, the automatic sewing machine 20 is a general feed sewing machine or an upper feed sewing machine, and as shown in FIGS. 8 and 9A, the feed mechanism 33 includes an upper feed member 34 and an upper presser member 35. It is prepared. The upper feed member 34 is driven so as to draw an elliptical locus centered on an upper feed axis (not shown) extending in the left-right direction Y in conjunction with the vertical movement of the sewing needle 31, and while moving in the vertical direction Z. Move in the feed direction X. The upper presser member 35 is driven linearly along the vertical direction Z. The upper feed member 34 and the upper presser member 35 are driven so that when one member is arranged at the lower end of the movable range, the other member is arranged at the upper end of the movable range.

More specifically, as shown in FIGS. 8 and 9A, the upper feed member 34 has a base portion 34B extending in the vertical direction Z and a front side of the feed direction X from the lower end of the base portion 34B. The feed leg portion 34K is provided with a through hole 34A (see FIG. 8) through which the sewing needle 31 is inserted. Further, the upper presser member 35 has a base portion 35B extending in the vertical direction Z, and presser leg portions 35K and 35K that are bifurcated from the lower end of the base portion 35B and protrude toward the front side in the feed direction X. is doing. The presser legs 35K and 35K are arranged so as to sandwich the feed leg portion 34K of the upper feed member 34 in the left-right direction Y.

As shown in FIGS. 4 and 6, the automatic sewing machine 20 includes a thread feeding device 40 for keeping the tension of the needle thread T constant. The thread feeding device 40 includes a thread stand rotating device 41 and a rotation control device 45. The thread stand rotary device 41 includes a fixed base 41A, a rotary base 42 mounted on the fixed base 41A, and a rotary drive source 42M for rotationally driving the rotary base 42. A thread stand 43 to which the thread piece 44 around which the needle thread T is wound can be attached is fixed to the rotation base 42. Then, when the rotation base 42 is rotated by the rotation drive source 42M, the needle thread T is supplied from the thread piece 44.

The rotation control device 45 includes a base plate 46 arranged substantially vertically, and a moving pulley 48 that moves in the vertical direction in front of the base plate 46. Specifically, a pair of fixed pulleys 47 and 47 are rotatably attached to the upper part of the front surface of the base plate 46, and the moving pulley 48 is laterally sandwiched between the pair of fixed pulleys 47 and 47. It is arranged so that it can be used. Then, the needle thread T supplied from the thread piece 44 is hung on the pair of fixed pulleys 47 and 47 from above, and the needle thread T between the pair of fixed pulleys 47 and 47 is lowered to the moving pulley 48. It is hung from the side.

As shown in FIG. 7, the moving pulley 48 has a large diameter portion 48A, a small diameter portion 48B overlapping the large diameter portion 48A from the front side, and a communication shaft connecting the central portions of the large diameter portion 48A and the small diameter portion 48B. It is provided with a portion 48C. The needle thread T is hung on the thread hooking groove 48M formed on the outer peripheral surface of the small diameter portion 48B.

A pair of support shafts 46S and 46S fixed to the base plate 46 are received between the large diameter portion 48A and the small diameter portion 48B. The connecting shaft portion 48C is sandwiched between the pair of support shafts 46S and 46S. As a result, the movement of the moving pulley 48 in the front-rear direction and the lateral direction is restricted. As shown in FIG. 6, the pair of support shafts 46S and 46S are passed to the pair of protrusions 46T and 46T protruding forward from the upper end and the lower end of the base plate 46. Further, the base plate 46 is formed with an elongated hole 46A extending in the vertical direction in order to avoid interference with the moving pulley 48.

As shown in FIG. 6, the rotation control device 45 includes a rotation switch 49A, a stop switch 49B, and an abnormality detection switch 49C in order from the top. These switches 49A to 49C detect the vertical position of the moving pulley 48. Here, when the moving pulley 48 is arranged between the rotation switch 49A and the stop switch 49B, the tension of the needle thread T becomes appropriate. Then, when the rotary switch 49A arranged at the top of the three switches 49A to 49C detects the moving pulley 48, the rotation control device 45 rotates the rotation drive source 42M of the thread stand rotation device 41. Then, the needle thread T bends and the moving pulley 48 moves downward. Further, when the stop switch 49B arranged in the middle of the three switches 49A to 49C detects the moving pulley 48, the rotation control device 45 stops the rotation drive source 42M of the thread stand rotation device 41. Then, the needle thread T is stretched and the moving pulley 48 moves upward. In this way, the rotation control device 45 controls the thread stand rotation device 41 so that the tension of the needle thread T becomes appropriate by arranging the position of the moving pulley 48 between the rotation switch 49A and the stop switch 49B. do.

When the abnormality detection switch 49C arranged at the bottom of the three switches 49A to 49C detects the moving pulley 48, the rotation control device 45 determines that the rotation drive source 42M has abnormally rotated. In this case, the rotation control device 45 urgently stops the thread stand rotation device 41 and transmits an error occurrence signal to the sewing machine control unit 20A.

The detection of the moving pulley 48 by the switches 49A to 49C is performed as follows. That is, as shown in FIG. 7, the rotary switch 49A is composed of an optical sensor and includes a light emitting element 49H and a light receiving element 49J facing each other in the front-rear direction. A space through which the large diameter portion 48A of the moving pulley 48 can pass is provided between the light emitting element 49H and the light receiving element 49J. When the moving pulley 48 approaches the rotary switch 49A, the light emitted from the light emitting element 49H is blocked by the large diameter portion 48A and is not detected by the light receiving element 49J, the rotary switch 49A is turned on and the thread stand 43 is rotated. Is started. Then, when the moving pulley 48 is separated from the rotary switch 49A and the light from the light emitting element 49H is detected by the light receiving element 49J, the rotary switch 49A is turned off, but the thread stand 43 continues to rotate.

Like the rotary switch 49A, the stop switch 49B is also composed of an optical sensor, and includes a light emitting element and a light receiving element (both not shown) facing each other in the front-rear direction. A space through which the large diameter portion 48A of the moving pulley 48 can pass is provided between the light emitting element and the light receiving element of the stop switch 49B. When the moving slide 48 approaches the stop switch 49B and the light emitted from the light emitting element of the stop switch 49B is blocked by the large diameter portion 48A and cannot be detected by the light receiving element, the stop switch 49B is turned on and the thread stand 43 is turned on. The rotation stops. Then, when the moving pulley 48 is separated from the stop switch 49B and the light from the light emitting element is detected by the light receiving element, the stop switch 49B is turned off, but the rotation of the thread stand 43 remains stopped. As described above, in the present embodiment, the position of the moving pulley 48 in the rotation control device 45 is kept within a certain range by the on operation of the rotation switch 49A and the stop switch 49B so that the tension of the needle thread T does not fluctuate significantly.

Since the abnormality detection switch 49C has the same configuration as the rotary switch 49A and the stop switch 49B, the description regarding the configuration of the abnormality detection switch 49C will be omitted. As in the case of the rotation switch 49A and the stop switch 49B, the rotation control device 45 detects that the moving pulley 48 is near the abnormality detection switch 49C by the on operation of the abnormality detection switch 49C, and sets the automatic sewing system 100. Stop.

As shown in FIG. 8, the automatic sewing machine 20 is provided with a work guide 61 for positioning the skin material 11 with respect to the pot base 32 that receives the skin material 11. When the skin material 11 is addressed to the pot base 32 of the automatic sewing machine 20, the work guide 61 is arranged at a position away from the pot base 32 in order to avoid interference with the skin material 11, and when sewing is started, the work guide 61 is arranged. It is driven by the work guide drive unit 62 (see FIG. 4) and is arranged in the vicinity of the kettle stand 32. Specifically, the work guide 61 is arranged to face the front wall 11F of the skin material 11 and is abutted against an L-shaped corner portion of the skin material 11. Then, the sewn portion of the skin material 11 is arranged below the sewing needle 31.

As shown in FIG. 4, the automatic sewing machine 20 includes a thread cutting device 50 that cuts the needle thread T connected to the skin material 11 after forming the decorative stitch S on the skin material 11. As shown in FIG. 9A, the thread cutting device 50 is provided with a cutter 51 for cutting the needle thread T and a clamp 52 for holding the needle thread T on the rear side of the sewing needle 31. ing. The cutter 51 is composed of, for example, a heat cutter. As shown in FIG. 9B, the clamp 52 has a pair of movable portions 52A and 52A that are brought into contact with and separated from each other in the left-right direction Y, and the needle thread T is sandwiched by the pair of movable portions 52A and 52A. .. The pair of movable portions 52A and 52A are driven by the clamp drive portion 52K (see FIG. 4).

As shown in FIG. 9A, the thread cutting device 50 includes a guide member 53 for guiding the needle thread T to the clamp 52 between the clamp 52 and the sewing needle 31. As shown in FIG. 9B, the guide member 53 is formed with a notch 54 from the lower end of the guide member 53 upward. The cutout portion 54 includes a narrowing portion 54A that becomes narrower toward the upper side, and a linear portion 54B extending upward from the narrowing portion 54A. Arc-shaped guide portions 55 curved so as to approach each other in the left-right direction Y are formed on both side portions of the guide member 53 facing the throttle portion 54A. Further, the linear portion 54B is arranged so as to be sandwiched between the pair of movable portions 52A and 52A of the clamp 52 in the left-right direction Y. Then, when the robot 90 moves the skin material 11 upward and the needle thread T that passes through the needle hole of the sewing needle 31 and is connected to the skin material 11 hits the lower end of the guide member 53, the needle thread T is guided in an arc shape. It is guided to the linear portion 54B by the portion 55. As a result, the needle thread T is guided between the pair of movable portions 52A and 52A of the clamp 52.

By the way, in the automatic sewing machine 20, when the next skin material 11 is addressed to the pot stand 32 in a state where the needle thread T is not cut by the thread cutting device 50, the needle thread T connected to the skin material 11 is sewn to the next skin material 11. The problem of being struck can arise. In order to solve such a problem, the automatic sewing machine 20 includes a thread break sensor 70 for confirming that the needle thread T has been cut by the thread cutting device 50 (see FIG. 4).

As shown in FIGS. 5 and 10A, the thread break sensor 70 is wound with the needle thread T between the thread feeder 50 and the sewing needle 31 and rotates as the needle thread T moves. It includes a rotating wheel 71 and a rotation sensor 75 that detects the rotation of the rotating wheel 71. Specifically, the thread break sensor 70 is arranged between a pair of side walls 76, 76, and a thread insertion hole 76A is formed through each side wall 76. Then, the needle thread T that has passed through the thread insertion hole 76A of one side wall 76 is wound around the rotary wheel 71 and passes through the thread insertion hole 76A of the other side wall 76.

As shown in FIG. 10B, the rotary wheel 71 is provided with a flange portion 72 overhanging outward in the radial direction and a overhanging piece 73 displaced in the axial direction. Then, the needle thread T is wound once, for example, around the portion of the rotating wheel 71 sandwiched between the flange portion 72 and the overhanging piece 73 in the axial direction. The overhanging piece 73 has a fan shape and is arranged in a part of the rotating wheel 71 in the circumferential direction (see FIG. 10A). In this embodiment, the overhanging piece 73 is formed in a semicircular shape.

As shown in FIG. 10B, the rotation sensor 75 includes a light emitting element 75H and a light receiving element 75J that face each other in the axial direction of the rotating wheel 71. A space through which the overhanging piece 73 of the rotating wheel 71 can pass is formed between the light emitting element 75H and the light receiving element 75J. Here, as described above, the overhanging piece 73 is arranged in a part of the rotating wheel 71 in the circumferential direction. Therefore, when the rotating wheel 71 rotates, the light from the light emitting element 75H is received by the light receiving element 75J and the rotation sensor 75 is turned on (states shown in FIGS. 11A and 11B) and light emission. The light emitted from the element 75H toward the light receiving element 75J is blocked by the overhanging piece 73, and the rotation sensor 75 is turned off (the state shown in FIGS. 10A and 10B). do.

Here, when the needle thread T is cut by the thread cutting device 50, even if the robot 90 moves the skin material 11 on which the decorative stitch S is formed, the thread feeding device 50 and the sewing needle 31 are separated from each other. The needle thread T does not move. At this time, the rotating wheel 71 does not rotate, and the on / off state of the rotation sensor 75 does not change. On the other hand, when the needle thread T is not cut by the thread cutting device 50, when the robot 90 moves the skin material 11 on which the decorative stitch S is formed, the thread feeding device 50 and the sewing needle 31 The needle thread T in between moves. At this time, the rotating wheel 71 rotates, and the on / off state of the rotation sensor 75 changes periodically. As described above, in the present embodiment, it is possible to know whether or not the needle thread T has been cut depending on whether or not the on / off state of the rotation sensor 75 changes periodically. The thread break sensor 70 can detect the break of the needle thread T even when the needle thread T is broken due to an accident during sewing.

This concludes the description of the configuration of the automatic sewing system 100. In the present embodiment, the cutter 51 corresponds to the "cutting means" of the present invention, and the clamp 52 corresponds to the "holding means" of the present invention. Further, the thread breakage sensor 70 corresponds to the "thread breakage detection means" of the present invention, and the rotation sensor 75 corresponds to the "rotation detection means" of the present invention.

Next, a method of manufacturing the skin material 10 with decorative stitches using the automatic sewing system 100 will be described. In order to manufacture the skin material 10 with decorative stitches, first, the skin material 11 shaped into a three-dimensional shape is set at a predetermined position on the work table 102 (see FIG. 3). When the setting of the skin material 11 on the work stand 102 is completed, the robot 90 holds the skin material 11 and addresses the cover of the skin material 11 to the kettle stand 32 which is the receiving portion for receiving the skin material 11 in the automatic sewing machine 20. The sewn portion is arranged below the sewing needle 31.

When the skin material 11 is addressed to the pot base 32 of the automatic sewing machine 20, the automatic sewing machine 20 starts sewing, and the robot 90 moves the skin material 11 to a predetermined pattern to form a decorative stitch S on the skin material 11. do. Specifically, the robot 90 moves the skin material 11 in the feed direction X of the automatic sewing machine 20 from the state where the L-shaped corner portion of the skin material 11 is addressed on the kettle stand 32. At this time, since the L-shaped corner portion of the skin material 11 is abutted against the work guide 61 of the automatic sewing machine 20, it becomes easy to maintain the state in which the sewn portion of the skin material 11 is arranged below the sewing needle 31. See FIG. 8).

When the decorative stitch S is formed on the skin material 11, the automatic sewing machine 20 finishes sewing, and the robot 90 removes the skin material 11 from the top of the kettle stand 32. At this time, the automatic sewing machine 20 cuts the bobbin thread by a bobbin thread cutting device (not shown). Next, the robot 90 moves the skin material 11 to the rear side of the sewing needle 31, and the automatic sewing machine 20 holds the needle thread T connected to the skin material 11 through the needle hole of the sewing needle 31 by the clamp 52. Then, the automatic sewing machine 20 cuts the needle thread T between the skin material 11 and the clamp 52 at a position close to the clamp 52 by the cutter 51 while the needle thread T is held by the clamp 52. As described above, in the present embodiment, since the needle thread T is held by the clamp 52 and then the needle thread T is cut, the cutting of the needle thread T can be stabilized.

When the cutting of the needle thread T is completed, the robot 90 carries the skin material 11 to a predetermined work collection place, releases the skin material 11, holds the next skin material 11 from the work storage 102, and decorates the surface material 11 with the automatic sewing machine 20. The formation of the stitch S is started. Here, when the needle thread T is not cut, the needle thread T moves together with the skin material 11 when the robot 90 carries the skin material 11 to the work collection place. Then, the thread break sensor 70 detects that the needle thread T is not cut and notifies the abnormality. As described below, when the robot 90 carries the skin material 11 to the work collection site, the needle thread T is held by the clamp 52. However, the holding force of the clamp 52 is small enough not to hinder the movement of the skin material 11 by the robot 90.

The next skin material 11 is addressed to the pot base 32 of the automatic sewing machine 20, and the automatic sewing machine 20 starts sewing. Here, the automatic sewing machine 20 continues to hold the needle thread T by the clamp 52 until the next skin material 11 is addressed to the pot base 32 of the automatic sewing machine 20. The automatic sewing machine 20 releases the holding of the needle thread T by the clamp 52 after the needle thread T is sewn or double sewn on the next skin material 11. As described above, in the present embodiment, since the holding of the needle thread T by the clamp 52 is released after sewing to the next skin material 11 is started, the end portion of the needle thread T at the start of sewing is the needle thread T or the lower thread. It prevents the entanglement of threads and the formation of lumps, that is, the formation of bird's nests.

In the automatic sewing system 100, the above-mentioned operation is repeated to sequentially form decorative stitches S on the plurality of skin materials 11. Then, the skin material 10 with a plurality of decorative stitches is sequentially manufactured.

In the method for manufacturing the decorative stitch S of the present embodiment, since the decorative stitch S is formed on the skin material 11 by the robot 90 and the automatic sewing machine 20, it is compared with the case where the decorative stitch S is formed by human hands. As a result, the stitches of the decorative stitch S are less likely to be uneven or twisted, and it is possible to reduce the occurrence of defective products.

Further, in the present embodiment, after the thread breakage sensor 70 detects the breakage of the needle thread, the next skin material 11 is addressed to the pot base 32 of the automatic sewing machine 20 to start forming the decorative stitch S. It is possible to prevent the decorative stitch S from being formed on the next skin material 11 while the needle thread T remains uncut. Further, even when an abnormality occurs in which the needle thread T is cut during sewing, the abnormality can be detected. Moreover, since the cutting of the needle thread T is detected by detecting the rotation of the rotating wheel 71 around which the needle thread T is wound, the detection accuracy is higher than that in the case of detecting the movement of the needle thread T itself. Improvement is planned.

[Other embodiments]
The present invention is not limited to the above embodiments, and for example, embodiments as described below are also included in the technical scope of the present invention, and various other than the following, as long as they do not deviate from the gist. It can be changed and implemented.

(1) In the above embodiment, the skin material 10 with decorative stitches is used for the instrument panel 111, but may be used for vehicle interior materials such as door trims, pillar garnishes, and console boxes, for example.

(2) In the above embodiment, the decorative stitch S is a single type, but it may be a double stitch or various forms.

(3) In the above embodiment, the automatic sewing machine 20 is a post-type sewing machine, but it may be a flatbed sewing machine depending on the shape of the skin material 11.

(4) In the above embodiment, the rotating wheel 71 of the thread breakage sensor 70 may be configured to include a plurality of overhanging pieces 73 (see FIGS. 12A and 12B). In this case, it is preferable that the plurality of overhanging pieces 73 are arranged at equal intervals in the circumferential direction of the rotating wheel 71. As shown in FIG. 12A, the overhanging piece 73 is preferably fan-shaped, but may be rectangular (see FIG. 12B) or triangular.

(5) In the above embodiment, the cutter 51 is not limited to the heat cutter, and may be a scissors type that cuts by sandwiching the needle thread T.

(6) In the above embodiment, the guide member 53 may be provided integrally with the clamp 52 or may be provided separately from the clamp 52. The guide member 53 may be provided with a guide portion (notch portion 54 of the above embodiment) for guiding the needle thread T in the clamp 52, for example, the notch shown in FIG. 13A or FIG. 13B. The configuration may include a unit 54. In the example of FIG. 13A, the throttle portion 54A of the notch portion 54 is formed in a trapezoidal shape. In the example of FIG. 13B, the entire cutout portion 54 is composed of a triangular throttle portion 54A.

(7) In the above embodiment, one robot 90 is prepared, but two robots or three or more robots may be prepared. In that case, the robot sequentially addresses the skin material 11 to the pot base 32 of the automatic sewing machine 20 to form the decorative stitch S.

10 Outer skin material with decorative stitch 11 Outer skin material 20 Automatic sewing machine 40 Thread feeder 50 Thread cutting device 51 Cutter 52 Clamp 70 Thread break sensor 71 Rotating body 75 Rotating sensor 90 Robot 100 Automatic sewing system S Decorative stitch T Upper thread

Claims (7)

A skin material with a decorative stitch that is formed by the automatic sewing machine by holding the skin material shaped into a three-dimensional shape on the robot and directing it to the receiving part of the automatic sewing machine and moving it to a predetermined pattern. It ’s a manufacturing method,
The automatic sewing machine has
A holding means for holding the needle thread connected to the skin material, and
After forming the decorative stitch, a cutting means for cutting the needle thread connected to the skin material is provided.
After forming the decorative stitch, the skin material is moved by the robot, and the needle thread connected to the skin material is held by the holding means, and the needle thread is cut by the cutting means. The holding of the needle thread by the holding means is continued until the next skin material is addressed to the receiving portion of the automatic sewing machine.
A method for manufacturing a skin material with a decorative stitch, which releases the holding of the needle thread by the holding means after starting sewing of the decorative stitch. The method for manufacturing a skin material with decorative stitches according to claim 1, wherein the holding force for holding the needle thread is such that the holding force allows the robot to move the skin material. The method for manufacturing a skin material with decorative stitches according to claim 1 or 2, wherein the automatic sewing machine is provided with a guide member for guiding the needle thread connected to the skin material to the holding means. The automatic sewing machine is provided with a thread breakage detecting means for detecting that the needle thread has broken.
The needle thread is cut by the cutting means, and after the thread breakage detecting means detects that the needle thread has been cut, the next skin material is automatically produced by the robot or a robot different from the robot. The method for manufacturing a skin material with a decorative stitch according to claim 1, wherein the decorative stitch is formed by addressing the receiving portion of the sewing machine. The thread breakage detecting means includes
A rotary wheel around which the needle thread is wound between the thread feeding device for feeding the needle thread and the skin material.
The method for manufacturing a skin material with decorative stitches according to claim 4, wherein a rotation detecting means for detecting the rotation of the rotating wheel is provided. The skin with decorative stitches according to any one of claims 1 to 5, wherein the skin material has a laminated structure having an outer layer made of elastoma and a lining layer made of foamed resin. Material manufacturing method. The method for manufacturing a skin material with decorative stitches according to claim 1, wherein the robot is allowed to carry the skin material from the work standby portion to the receiving portion of the automatic sewing machine.

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