Workpiece transport device

Abstract

Provided is a method for transporting a workpiece when bending the workpiece by a press brake which comprises a die that supports the workpiece and a punch that is disposed above the die and that presses the workpiece supported by the die, wherein, before or after bending, the workpiece is intermittently transported in the direction of transport of the workpiece in such a manner that: an upstream side transport device which is disposed on the upstream side of the press brake in the direction of transport is moved in the direction of transport while an end part of the workpiece which is located on the upstream side in the direction of transport is pressed by the upstream side transport device; and the workpiece is supported from below by a support base which is disposed on the downstream side in the direction of transport such that the support base fits with the shape of the workpiece after pressing by the punch.

Description

[Technical Field]

[0001] The present disclosure relates to a workpiece transport method, a workpiece transport device, and a workpiece transport program. [Background technology]

[0002] Conventionally, bending apparatuses that bend plate materials have been known. For example, Patent Document 1 discloses a bending apparatus in which a workpiece pusher presses the workpiece against a bag gauge when transporting the workpiece to a predetermined position. Patent Document 2 also discloses a bending apparatus in which supports are fixed to the upstream and downstream ends of the workpiece in the transport direction, and the holding part of an upstream moving device is hooked to one support and the holding part of a downstream moving device is hooked to the other support. In this bending apparatus, the workpiece is transported by moving each moving device with each holding part hooked to the support. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 3-297516 [Patent Document 2] Japanese Patent Application Publication No. 2019-081184 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the bending device of Patent Document 1, which uses a work pusher to push the workpiece to a predetermined position, has a problem in that, particularly in incremental forming, which obtains a desired shape by repeatedly conveying and pressing the workpiece, as the amount of bending increases, the accuracy of conveying the workpiece to the predetermined position decreases. Furthermore, the bending device of Patent Document 2 requires a process of fixing a support tool to the workpiece and a process of hooking the holder of the moving device onto the support tool. Therefore, a simpler method of conveying the workpiece has been desired.

[0005] Therefore, an object of the present disclosure is to provide a workpiece transport method, a workpiece transport device, and a workpiece transport program that can increase transport accuracy compared to conventional methods and transport a workpiece in a simple manner. [Means for solving the problem]

[0006] The workpiece transport method disclosed herein is a workpiece transport method for transporting a workpiece during bending processing using a press brake having a die that supports the workpiece and a punch that is arranged above the die and presses the workpiece supported by the die, in which, before or after the bending processing, an upstream transport device arranged upstream of the press brake in the transport direction of the workpiece presses the upstream end of the workpiece in the transport direction while the upstream transport device is moved in the transport direction, and a receiving table arranged downstream in the transport direction supports the workpiece from below so as to conform to the shape of the workpiece after it has been pressed by the punch, thereby intermittently transporting the workpiece in the transport direction.

[0007] The work transport device disclosed herein is a work transport device that transports a workpiece during bending processing using a press brake having a die that supports the workpiece and a punch that is arranged above the die and presses the workpiece, and includes an upstream transport device that is arranged upstream of the press brake in the transport direction of the workpiece, a transport drive device that moves the upstream transport device in the transport direction, a receiving table that is arranged downstream in the transport direction and supports the workpiece from below so as to conform to the shape of the workpiece after it has been pressed by the punch, and a control device, and the control device controls the transport drive device to move the upstream transport device in the transport direction while pressing the upstream end of the workpiece in the transport direction against the upstream transport device before or after the bending processing, thereby intermittently transporting the workpiece in the transport direction.

[0008] The work transport program disclosed herein is a work transport program executed by a computer in a work transport device that transports the work when the work is bent using a press brake that has a die that supports the work and a punch that is arranged above the die and presses the work supported by the die, and causes the computer to function as a transport control means that, before or after the bending process, moves an upstream transport device arranged upstream of the press brake in the transport direction of the work while pressing the upstream end of the work in the transport direction, and supports the work from below on a receiving table arranged downstream in the transport direction so as to conform to the shape of the work after it has been pressed by the punch, thereby intermittently transporting the work in the transport direction. [Effects of the Invention]

[0009] According to the present disclosure, it is possible to provide a workpiece transport method, a workpiece transport device, and a workpiece transport program that can improve transport accuracy compared to conventional methods and transport a workpiece in a simple manner. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a plan view showing a bending system including a plurality of workpiece transport devices according to an embodiment of the present disclosure. [Figure 2] 2 is a perspective view of the workpiece transport device of FIG. 1 as seen from the downstream side in the transport direction. FIG. [Figure 3] 2 is a perspective view of the workpiece transport device of FIG. 1 as seen from the upstream side in the transport direction. FIG. [Figure 4] FIG. 2 is a block diagram showing a control system in the workpiece transport device. [Figure 5] FIG. 10 is a schematic diagram showing an upstream conveying device that presses the workpiece during the first bending. [Figure 6] FIG. 10 is a schematic diagram showing an upstream transport device and a downstream transport device that press the workpiece during re-bending. [Figure 7]10A and 10B are diagrams showing a state in which the positioning portions of the contact portions are engaged with the positioned portion of the workpiece. [Figure 8A] FIG. 2 is a side view showing the arrangement of distance sensors. [Figure 8B] FIG. 2 is a front view showing the arrangement of distance sensors. [Figure 9] FIG. 10 is a front view showing the arrangement of distance sensors according to another example. [Figure 10] 1 is a flowchart showing a flow of bending processing. [Figure 11] 1 is a flowchart showing a flow of bending processing. [Figure 12] 10A and 10B are diagrams for explaining a method of pressing the surface edge of a workpiece with a punch. [Figure 13] 10A and 10B are diagrams for explaining a method for acquiring values ​​relating to the shape of the surface end portion of a workpiece. [Figure 14] 10A and 10B are diagrams illustrating a manner in which values ​​relating to the shape of a workpiece are acquired while the workpiece is held by a suction device. [Figure 15] 10A and 10B are diagrams for explaining deformation portions provided in the upstream-side transport device and the downstream-side transport device. [Figure 16A] 10A and 10B are diagrams illustrating the flow of workpiece transport and bending of the end portion by an upstream transport device and a downstream transport device having a deformation section. [Figure 16B] 10A and 10B are diagrams illustrating the flow of workpiece transport and bending of the end portion by an upstream transport device and a downstream transport device having a deformation section. [Figure 16C] 10A and 10B are diagrams illustrating the flow of workpiece transport and bending of the end portion by an upstream transport device and a downstream transport device having a deformation section. [Figure 16D] 10A and 10B are diagrams illustrating the flow of workpiece transport and bending of the end portion by an upstream transport device and a downstream transport device having a deformation section. [Figure 16E] 10A and 10B are diagrams illustrating the flow of workpiece transport and bending of the end portion by an upstream transport device and a downstream transport device having a deformation section. [Figure 17]10A and 10B are diagrams showing a manner in which the cradle is rotated around a predetermined rotation axis by the cradle driving device. [Figure 18] 10A and 10B are diagrams showing how the cradle is raised and lowered by the cradle drive device. [Figure 19A] FIG. 10 is a diagram showing a plurality of rollers that support a workpiece from below. [Figure 19B] FIG. 10 is a diagram showing a state in which the roller is moved. [Figure 20] 10A and 10B are diagrams showing a manner in which the downstream roller guide is rotated. [Figure 21] 10A and 10B are diagrams showing how the upstream and downstream roller guides are rotated. DETAILED DESCRIPTION OF THE INVENTION

[0011] A workpiece transport method, a workpiece transport device, and a workpiece transport program according to an embodiment of the present disclosure will be described below with reference to the drawings. The workpiece transport method, the workpiece transport device, and the workpiece transport program described below are merely one embodiment of the present disclosure. Therefore, the present disclosure is not limited to the following embodiment, and additions, deletions, and modifications are possible within the scope of the present disclosure.

[0012] FIG. 1 is a plan view showing a bending system 200 including a plurality of work transportation devices 100 according to an embodiment of the present disclosure. FIG. 2 is a perspective view of the work transportation device 100 of FIG. 1 as seen from the downstream side in the transportation direction, and FIG. 3 is a perspective view of the work transportation device 100 of FIG. 1 as seen from the upstream side in the transportation direction. In the following description, the transportation direction of the work W transported by the work transportation device 100 is referred to as D1, and two directions perpendicular to the transportation direction D1 are referred to as a first orthogonal direction D2 and a second orthogonal direction D3. The second orthogonal direction D3 is, for example, an up-down direction, and is a direction in which the work W is pressed. The first orthogonal direction D2 corresponds to the intersecting direction.

[0013] The bending system 200 bends the workpiece W into a predetermined shape by repeating a process of pitch-transporting the flat workpiece W in the transport direction D1 and a process of pressing the workpiece W from a second orthogonal direction D3. As shown in FIG. 1, the bending system 200 includes a press brake 1 including a die 2 serving as a lower die and a punch 3 serving as an upper die, and a plurality of workpiece transportation devices 100. Although FIG. 1 illustrates four workpiece transportation devices 100 arranged side by side in the first orthogonal direction D2, the number of workpiece transportation devices 100 may be one, or five or more.

[0014] The die 2 extends in the first orthogonal direction D2. The upper edge of the die 2 is chamfered. A groove 2a is provided at the top of the die 2, and a backup plate BP is provided to cover the groove 2a. The backup plate BP supports the workpiece W. The backup plate BP is configured so as not to undergo plastic deformation when pressed by the punch 3 through the workpiece W. The die 2 supports the workpiece W. The punch 3 is positioned above the die 2. The punch 3 presses the workpiece W supported by the die 2. The punch 3 extends in the first orthogonal direction D2. For simplicity, the groove 2a and backup plate BP are omitted from Figure 4 onwards.

[0015] The work transportation devices 100 will be described. Each work transportation device 100 has the same configuration. The work transportation device 100 includes an upstream transportation device 15a including a contact portion 4a and a holding portion 5, a downstream transportation device 15b including a contact portion 4b and a holding portion 5, a receiving table 6, a roller guide 7, a guide rail 8, and a guide rail 9.

[0016] The upstream conveying device 15a is arranged upstream in the conveying direction D1 relative to the press brake 1. The contact portions 4a and 4b are formed in a block shape and are made of, for example, resin. The contact portion 4a contacts the upstream end Wz of the workpiece W. The contact portion 4a presses the end Wz without gripping it. The contact portion 4a is held by the holding portion 5. The holding portion 5 is connected to the conveying drive device 26 shown in FIG. 4. The holding portion 5 corresponds to the connection portion between the contact portion 4a and the conveying drive device 26 and is made of, for example, metal. The holding portion 5 rotates around an axis parallel to the first orthogonal direction D2. Note that when the flat workpiece W starts to be conveyed to the die 2 before bending, the side of the contact portion 4a or 4b that is located at a position with a long distance to the die 2 is defined as the upstream side of the conveying direction D1 relative to the press brake 1, and the opposite side is defined as the downstream side of the conveying direction D1.

[0017] The downstream conveying device 15b is disposed downstream in the conveying direction D1 with respect to the press brake 1. The contact portion 4b contacts the downstream end Wk of the workpiece W. The contact portion 4b presses the end Wk without gripping it. The contact portion 4b is held by a holding portion 5 of the downstream conveying device 15b. The holding portion 5 is connected to a conveying drive device 26.

[0018] Before the workpiece W is pressed by the punch 3, the workpiece W is flat. Therefore, when the flat workpiece W is pressed and transported by the contact portion 4a, the contact portion 4a comes into surface contact with the upstream end Wz of the workpiece W. At this time, the contact portion 4a comes into surface contact with the upstream end face of the flat workpiece W that intersects with the face to be pressed by the punch 3. Therefore, in the present disclosure, the end Wz includes the upstream end face of the workpiece W.

[0019] On the other hand, after pressing the workpiece W with the punch 3 to form an arc-shaped bent workpiece W (hereinafter sometimes referred to as the initial bending), if the desired shape is not achieved, additional bending (hereinafter sometimes referred to as a re-bend) may be performed by pressing the punch 3 again. In this case, the workpiece W after the initial bending is pressed by the contact portions 4a and 4b and transported. In this case, since the workpiece W after the initial bending is arc-shaped, the contact portion 4a makes surface contact with the upstream end face of the flat workpiece W that intersects with the surface to be pressed by the punch 3, or makes line contact with the ridge (edge) that constitutes the end face. Furthermore, the contact portion 4b makes surface contact with the downstream end face of the flat workpiece W that intersects with the surface to be pressed by the punch 3, or makes line contact with the ridge that constitutes the end face. Therefore, in this disclosure, the end portion Wz further includes the ridge that constitutes the upstream end face of the workpiece W. Furthermore, the end portion Wk includes the downstream end face of the workpiece W and the ridge that constitutes the end face.

[0020] The receiving tables 6 support the workpiece W while it is being pressed or while the shape of the workpiece W is being measured. For example, two receiving tables 6 are provided on the upstream side of the conveying direction D1 and two are provided on the downstream side of the conveying direction D1, but one may be provided on the upstream side and one on the downstream side, or three or more may be provided. The receiving tables 6 on the upstream side are provided at a predetermined interval in the first orthogonal direction D2, and the receiving tables 6 on the downstream side are provided at a predetermined interval in the first orthogonal direction D2.

[0021] The receiving table 6 has multiple rollers 6r. The upper edge of the receiving table 6 is formed in an arc shape. Each roller 6r is arranged in an arc shape on the upper edge of the receiving table 6 at a predetermined interval in the conveying direction D1. The rollers 6r are supported between two plate members that make up the receiving table 6 and are arranged at a predetermined interval in the first orthogonal direction D2, and are rotatable around an axis parallel to the first orthogonal direction D2. The rollers 6r rotate when the workpiece W comes into contact with them. Preferably, the line connecting the upper edges of the multiple rollers 6r matches the contour shape of the workpiece W after bending. The receiving table 6 moves in a direction toward and away from the workpiece W, such as the second orthogonal direction D3. Alternatively, the receiving table 6 may rotate around a predetermined rotation axis parallel to the first orthogonal direction D2, instead of moving toward and away from the workpiece W. Furthermore, in the receiving base 6, instead of the rollers 6r being journaled between two plates, each of the rollers 6r may be movable in the second orthogonal direction D3 by a motor or the like.

[0022] The roller guides 7 support the workpiece W when it is being transported. For example, two roller guides 7 are provided on the upstream side of the transport direction D1, and two roller guides 7 are provided on the downstream side of the transport direction D1, but one may be provided on each of the upstream and downstream sides, or three or more may be provided. The downstream end of the upstream roller guide 7 is located downstream of the downstream end of the upstream receiving table 6. The upstream end of the downstream roller guide 7 is located upstream of the upstream end of the downstream receiving table 6. The upstream roller guides 7 are provided at a predetermined interval from each other in the first orthogonal direction D2, and the downstream roller guides 7 are provided at a predetermined interval from each other in the first orthogonal direction D2.

[0023] The roller guide 7 extends in the conveying direction D1. The roller guide 7 has a plurality of rollers 7r. Each roller 7r is supported between two plates that constitute the roller guide 7 and are arranged at a predetermined interval in the first orthogonal direction D2, and is rotatable around an axis parallel to the first orthogonal direction D2. The rollers 7r rotate when the workpiece W comes into contact with them. The roller guide 7 rotates around a predetermined rotation axis parallel to the first orthogonal direction D2. The roller guide may have any shape, but is preferably flat.

[0024] The guide rails 9 are provided on both the upstream and downstream sides of the conveying direction D1. The guide rails 9 extend in the conveying direction D1. The guide rails 9 support the holding portion 5 from below and guide the holding portion 5 in the conveying direction D1 and in the direction opposite to the conveying direction D1. This causes the contact portions 4a and 4b to move in the conveying direction D1 and in the direction opposite to the conveying direction D1.

[0025] The guide rails 8 are provided on both the upstream and downstream sides of the conveying direction D1. The guide rails 8 extend in a first orthogonal direction D2. The guide rails 8 support the guide rails 9 from below and guide the guide rails 9 and the holding portions 5 supported on the guide rails 9 in the first orthogonal direction D2. This causes the contact portions 4a and 4b to move in the first orthogonal direction D2.

[0026] As shown in Figures 2 and 3, a distance sensor 10 is provided at the contact portion 4a. The distance sensor 10 detects the distance between the contact portion 4a and the upstream end Wz of the workpiece W. If the distance detected by the distance sensor 10 is 0, this means that the contact portion 4a is in contact with the end Wz. The distance sensor 10 is, for example, a proximity sensor, a laser ranging sensor, or an image sensor. When an image sensor is used as the distance sensor 10, the size of the ends Wz and Wk of the workpiece W in the image obtained by the image sensor can be obtained as information about the distance (without directly calculating the distance). In this way, information about the distance is not limited to direct distance information, but also includes information that allows the distance to be indirectly estimated.

[0027] A distance sensor 10 is provided at the contact portion 4b. The distance sensor 10 provided at the contact portion 4b detects the distance between the contact portion 4b and the downstream end Wk of the workpiece W. In Fig. 3, the workpiece W is indicated by a two-dot chain line to clearly show each component of the conveying device 100.

[0028] The workpiece conveying device 100 is equipped with a plurality of shape sensors 11. Each shape sensor 11 is disposed near the die 2. Specifically, each shape sensor 11 is disposed below the workpiece W supported by the die 2. Each shape sensor 11 is disposed upstream of the conveying direction D1 at a predetermined interval in the first orthogonal direction D2, and downstream of the conveying direction D1 at a predetermined interval in the first orthogonal direction D2. The shape sensors 11 are, for example, proximity sensors, laser distance measuring sensors, contact sensors, or image sensors. The shape sensors 11 acquire values ​​related to the shape of the workpiece W. Specifically, the shape sensors 11 acquire the angle (for example, the angle with respect to the horizontal plane) or curvature of the portion of the workpiece W pressed by the punch 3.

[0029] The upstream-side conveying device 15a and the downstream-side conveying device 15b are each provided with a suction device 12. The suction device 12 suctions and holds the workpiece W. Examples of the suction method of the suction device 12 include air suction using a suction cup and electromagnetic suction.

[0030] Fig. 4 is a block diagram showing a control system in the workpiece transportation device 100. As shown in Fig. 4, the workpiece transportation device 100 includes a control unit 20, a pressing drive device 25, a transport drive device 26, a roller drive device 35, a receiving table drive device 36, and a roller guide drive device 38.

[0031] The control unit 20 includes a control device 21, which is a CPU (Central Processing Unit), a ROM (Read Only Memory) 22, a RAM (Random Access Memory) 23, and an HDD (Hard Disk Drive) 24. The ROM 22 stores various information such as target positions to which the contact portions 4a, 4b should be moved when the workpiece W is being transported. The target positions are positions determined based on information about the contour R of the workpiece W to be formed, and determine each position in the transport direction D1 of the workpiece W and the height corresponding to that position. The RAM 23 is used as a processing area for the control device 21. The control device 21 corresponds to transport control means, and the ROM 22, RAM 23, and HDD 24 correspond to storage units.

[0032] A workpiece transport program for operating the workpiece transport device 100 of the present disclosure is stored in the HDD 24. The workpiece transport program may be received from an external device and stored in the HDD 24, or may be read from a computer-readable recording medium (e.g., a DVD-ROM or a USB flash memory) on which the workpiece transport program is recorded and stored.

[0033] The control device 21 controls the operation of the pressing drive device 25 so that the punch 3 is pressed against the workpiece W by a predetermined stroke amount. The control device 21 controls the operation of the pressing drive device 25 so that the punch 3 is separated from the workpiece W after being pressed against the workpiece W. The pressing drive device 25 is, for example, a motor and a hydraulic cylinder.

[0034] The control device 21 controls the operation of the transport drive device 26 so that the contact portions 4a, 4b move in the transport direction D1, the first orthogonal direction D2, and the second orthogonal direction D3 based on the target position. The transport drive device 26 will be described in detail later. The control device 21 also controls the operation of the suction device 12 so that the workpiece W is sucked and held.

[0035] The control device 21 controls the operation of the roller drive device 35 so that the rollers 6r of the receiving table 6 move in a direction toward the workpiece W and in a direction away from the workpiece W. The control device 21 also controls the operation of the receiving table drive device 36 so that the receiving table 6 rotates about a predetermined rotation axis. The control device 21 controls the operation of the roller guide drive device 38 so that the roller guide 7 rotates about a predetermined rotation axis. The system may be provided with both the roller drive device 35 and the receiving table drive device 36, or with either one of them.

[0036] The control device 21 receives information about the distance between the contact portion 4a and the upstream end Wz of the workpiece W from the distance sensor 10 located upstream in the conveying direction D1. The control device 21 receives information about the distance between the contact portion 4b and the downstream end Wk of the workpiece W from the distance sensor 10 located downstream in the conveying direction D1. The control device 21 changes the operation of the punch 3 and the operation of the conveying drive device 26 in accordance with the distance detected by each distance sensor 10. Specifically, for example, if the distance detected by each distance sensor 10 exceeds an allowable value, that is, if an unacceptable gap occurs between the workpiece W and the contact portions 4a and 4b, the control device 21 stops the operation of the punch 3 and the operation of the conveying drive device 26.

[0037] The control device 21 receives information about the angle or curvature of the pressed portion of the workpiece W from each shape sensor 11. The control device 21 may stop the operation of the punch 3 and the operation of the conveyance drive device 26 when an abnormality occurs, such as when the angle or curvature of the pressed portion of the workpiece W falls outside a predetermined range.

[0038] Fig. 5 is a schematic diagram showing the upstream transfer device 15a that presses the workpiece W during the first bending. Fig. 6 is a schematic diagram showing the upstream transfer device 15a and the downstream transfer device 15b immediately before and after they press the workpiece W during re-bending. Note that Fig. 5 omits the downstream transfer device 15b and the transfer drive device 26 that drives the downstream transfer device 15b.

[0039] The configuration of the transport drive device 26 that drives the upstream transport device 15a is the same as that of the transport drive device 26 that drives the downstream transport device 15b, so the following describes the configuration of the transport drive device 26 that drives the upstream transport device 15a as a representative example. The transport drive device 26 includes a first drive unit 26a, a second drive unit 26b, a third drive unit 26c, and a fourth drive unit 26d. A slide mechanism 31 and an elevating mechanism 32 are connected to the holding unit 5. The elevating mechanism 32 is, for example, a ball screw and is driven by the first drive unit 26a, which is a drive source such as a motor. The first drive unit 26a raises and lowers the elevating mechanism 32. This raises and lowers the holding unit 5, and therefore the contact unit 4a.

[0040] The slide mechanism 31 is, for example, a ball screw, and is driven by a second drive unit 26b, which is a drive source such as a motor. The second drive unit 26b causes the slide mechanism 31 to slide along the guide rail 9. As a result, the holder 5 slides along the guide rail 9, and the contact portion 4a moves accordingly in the conveying direction D1 and in the direction opposite to the conveying direction D1. Furthermore, the third drive unit 26c is, for example, a drive source such as a motor, and causes the slide mechanism 31 and the guide rail 9 to slide along the guide rail 8. As a result, the holder 5 slides along the guide rail 8, and the contact portion 4a moves accordingly in the first orthogonal direction D2.

[0041] Furthermore, the fourth drive unit 26d is a drive source such as a motor, and rotates a rotation shaft provided in the holder 5 about an axis parallel to the first orthogonal direction D2. This causes the suction device 12 to rotate about an axis parallel to the first orthogonal direction D2. The suction device 12 rotates according to the shape of the workpiece W and suctions the workpiece W.

[0042] When starting to transport the workpiece W to perform the first bending, the first drive unit 26a, the second drive unit 26b, and the third drive unit 26c move the contact unit 4a to a predetermined position in accordance with instructions from the control device 21. As a result, the contact unit 4a is positioned facing the end Wz of the workpiece W at a position separated from the end Wz in the transport direction D1. From this state, the second drive unit 26b moves the contact unit 4a in the transport direction D1 in accordance with instructions from the control device 21 to abut against the end Wz of the workpiece W, and then presses the end Wz of the workpiece W, moving the workpiece W to a position defined by the workpiece transport program. In this way, the workpiece W is transported in the transport direction D1.

[0043] On the other hand, when starting to transport the workpiece W to perform re-bending, the first drive unit 26a, the second drive unit 26b, and the third drive unit 26c move the contact portions 4a and 4b to predetermined positions in accordance with instructions from the control device 21. Because the workpiece W has a contour R during re-bending, the contact portions 4a and 4b also move in the second orthogonal direction D3. As a result, the contact portion 4a is positioned facing the end Wz of the workpiece W at a position spaced apart from the end Wz in the transport direction D1, and the contact portion 4b is positioned facing the end Wk of the workpiece W at a position spaced apart from the end Wk in the transport direction D1. From this state, the second drive unit 26b moves the contact portion 4a in the transport direction D1 in accordance with instructions from the control device 21 to abut the end Wz of the workpiece W, and then causes the contact portion 4a to press the end Wz of the workpiece W, thereby moving the workpiece W to a position defined by the workpiece transport program. Next, the second drive unit 26b moves the contact unit 4b in the opposite direction to the conveying direction D1 in accordance with instructions from the control unit 21, and brings it into contact with the end Wk of the workpiece W at a position defined by the workpiece conveying program. As a result, the end Wz of the workpiece W is pressed by the contact unit 4a, and the end Wk is brought into contact with the contact unit 4b. As a result, the workpiece W can be conveyed while being positioned with high precision by the contact units 4a and 4b.

[0044] FIG. 7 is a diagram showing a state in which the positioning portion 4i of the contact portions 4a, 4b is engaged with the positioned portion Wh of the workpiece W.

[0045] 7, a positioned portion Wh may be provided at each of the upstream end Wz and downstream end Wk in the conveying direction D1 of the workpiece W. A plurality of positioned portions Wh may be provided at the ends Wz and Wk of the workpiece W. The positioned portions Wh are formed, for example, in a convex shape extending outward from the ends Wz and Wk.

[0046] Meanwhile, the contact portions 4a and 4b are each provided with a positioning portion 4i. By engaging the positioning portion 4i with the positioned portion Wh, the workpiece W can be positioned with high precision in the first orthogonal direction D2.

[0047] The number and arrangement of the positioning portions 4i are determined according to the number and arrangement of the positioned portions Wh of the workpiece W. The positioning portions 4i are formed, for example, in a concave shape. Note that the positioned portions Wh are convex and the positioning portions 4i are concave, but this is not limiting, and the positioned portions Wh may be concave and the positioning portions 4i may be convex. Furthermore, the positioning portions 4i may be multi-step concave and the positioned portions Wh may be multi-step convex. Furthermore, the positioning portions 4i may be multi-step convex and the positioned portions Wh may be multi-step concave.

[0048] Fig. 8A is a side view showing the arrangement of the distance sensor 10, and Fig. 8B is a front view showing the arrangement of the distance sensor 10. Fig. 9 is a front view showing the arrangement of a distance sensor 10a according to another example.

[0049] As shown in FIGS. 8A and 8B, one or more distance sensors 10 are provided on the contact portion 4a. Each distance sensor 10 is provided on a surface of the contact portion 4a that intersects with the surface facing the end Wz of the workpiece W, i.e., on both sides of the contact portion 4a. The same applies to the distance sensors 10 on the contact portion 4b. Examples of distance sensors 10 include proximity sensors and laser ranging sensors. When the distance sensors 10 are proximity sensors, each distance sensor 10 is arranged at a different height to increase the detection width in the height direction of the contact position of the end Wz of the workpiece W against the contact portion 4a. Note that if one distance sensor 10 can detect the required detection width in the height direction, only one distance sensor 10 may be arranged. Furthermore, when multiple distance sensors 10 are arranged in the height direction, if there is no area within the detection width in the height direction of the sensor 10 where the workpiece W cannot be detected, it is not necessarily necessary to provide them on both sides of the contact portion 4a.

[0050] As another example of the distance sensor 10, a distance sensor 10a, which is a laser distance measuring sensor, may be employed. As shown in FIG. 9, multiple distance sensors 10a are provided on the contact portion 4a. Each distance sensor 10a is provided on a surface constituting the contact portion 4a that intersects with the surface facing the end Wz of the workpiece W, i.e., on both sides of the contact portion 4a. The same applies to the distance sensors 10a on the contact portion 4b. To increase the detection width in the height direction of the contact position of the end Wz of the workpiece W against the contact portion 4a, each distance sensor 10a is arranged so that the illumination height of its light source differs. By arranging the distance sensors 10 in this manner, information on the distance between the contact portions 4a, 4b and the end Wz, Wk of the workpiece W, or the distance between the contact portions 4a, 4b and the end Wz, Wk of the workpiece W, can be detected regardless of the position of the end Wz, Wk of the workpiece W approaching the contact portions 4a, 4b. Note that if one distance sensor 10 is capable of detecting the required detection width in the height direction, only one distance sensor 10 may be provided. Furthermore, when multiple distance sensors 10 are arranged in the vertical direction, if there is no area within the detection width of the sensor 10 in the vertical direction where the workpiece W cannot be detected, it is not necessarily necessary to install them on both sides of the contact portion 4a.

[0051] 10 and 11 are flowcharts showing the flow of bending. As shown in FIG. 10, the control device 21 presses the workpiece W with the contact portion 4a of the upstream conveying device 15a to convey the workpiece W from the upstream side to the downstream side so that the downstream surface edge Ws of the unformed flat workpiece W is positioned at a predetermined position on the die 2 (step S1). At this time, the control device 21 moves the downstream receiving table 6 to a position where it supports the workpiece W, and moves the upstream receiving table 6 to a position where it does not support the workpiece W. The control device 21 may change, for example, stop, the operation of the punch 3 and the conveying drive device 26 depending on the distance detected by the distance sensor 10 during the conveyance and bending of the workpiece W.

[0052] The control device 21 causes the punch 3 to press the downstream surface edge Ws of the workpiece W while the upstream edge Wz of the workpiece W is in contact with the contact portion 4a of the upstream conveying device 15a (step S2). In the present disclosure, the surface edge Ws refers to an interference region on the surface of the workpiece W on the upstream and downstream sides where there is a possibility of interference between the punch 3 and the contact portions 4a, 4b when the punch 3 presses the workpiece W.

[0053] Next, in order to measure the shape of the pressed downstream surface end Ws, the control device 21 presses the end Wz of the workpiece W with the contact portion 4a of the upstream transport device 15a, transports the workpiece W to a predetermined measurement position, and then calculates a value related to the shape of the pressed portion of the workpiece W from the detection result of the shape sensor 11 (step S3). Next, the control device 21 causes the contact portion 4a to press the end Wz of the workpiece W and transports the workpiece W to a predetermined position (step S4). The control device 21 causes the punch 3 to press the workpiece W (step S5). Then, the control device 21 presses the end Wz of the workpiece W with the contact portion 4a of the upstream transport device 15a, transports the workpiece W to a predetermined measurement position, and then calculates a value related to the shape of the pressed portion of the workpiece W from the detection result of the shape sensor 11 (step S6).

[0054] If the portion to be pressed next by the punch 3 based on the workpiece transport program is not the upstream surface end Ws (NO in step S7), the control device 21 returns to step S4 and repeats the subsequent processes. On the other hand, if the portion to be pressed next by the punch 3 based on the workpiece transport program is the upstream surface end Ws (YES in step S7), the control device 21 presses the end Wz of the workpiece W with the contact portion 4a to transport the workpiece W so that the upstream surface end Ws is positioned at a predetermined position on the die 2 (step S8).

[0055] The control device 21 retracts the contact portion 4a while the suction device 12 of the downstream transport device 15b is holding the workpiece W by suction, and then causes the punch 3 to press the upstream surface edge Ws of the workpiece W (step S9). Next, the control device 21 transports the workpiece W to a predetermined measurement position in the opposite direction to the transport direction D1, and then calculates a value relating to the shape of the pressed portion of the workpiece W from the detection result by the shape sensor 11 upstream of the die 2 (step S10).

[0056] Next, the control device 21 determines whether or not the workpiece W has a predetermined shape (step S11). In this case, the control device 21 can determine whether or not the workpiece W has a predetermined shape based on the calculated value related to the shape of the pressed portion of the workpiece W. If the workpiece W has a predetermined shape (YES in step S11), the control device 21 ends the bending process.

[0057] On the other hand, if the workpiece W does not have the predetermined shape (NO in step S11), the control device 21 executes rebending of the workpiece W as described below. Note that the following describes a case where rebending is performed on the downstream surface end Ws of the workpiece W, the upstream surface end Ws of the workpiece W, and all of the surface of the workpiece W (surface excluding the downstream and upstream surface end Ws). However, rebending of each portion may be omitted depending on the shape measurement results.

[0058] First, the control device 21 presses the end Wk of the workpiece W, which has been formed into an arc shape by the initial bending, against the contact portion 4b, and transports the workpiece W to a predetermined position in the opposite direction to the transport direction D1, and then causes the contact portion 4a of the upstream transport device 15a to transport the workpiece W from the upstream side to the downstream side so that the downstream surface end Ws of the workpiece W is positioned at a predetermined position on the die 2 (step S12). Note that the control device 21 may change, for example stop, the operation of the punch 3 and the operation of the transport drive device 26 depending on the distance detected by the distance sensor 10 during the transport and bending of the workpiece W.

[0059] When the area of ​​the workpiece W to be pressed in the re-bending is the downstream surface end Ws of the workpiece W, the control device 21 causes the suction device 12 of the upstream transport device 15a to suction and hold the workpiece W and retracts the contact portion 4b, and then causes the punch 3 to press the downstream surface end Ws of the workpiece W (step S13). Next, the control device 21 causes the contact portion 4a to transport the workpiece W to a predetermined measurement position, and then calculates a value related to the shape of the pressed portion of the workpiece W from the detection result by the shape sensor 11 (step S14).

[0060] Next, the control device 21 determines whether the workpiece W has a predetermined shape (step S15). If the workpiece W has not formed the predetermined shape (NO in step S15), the control device 21 pushes back the workpiece W with the contact portion 4b (step S12), and then repeats the processing from step S13 onwards.

[0061] On the other hand, if the workpiece W has a predetermined shape (YES in step S15), and the area of ​​the workpiece W to be pressed during re-bending is the area between the downstream surface end Ws and the upstream surface end Ws of the workpiece W, the control device 21 moves the contact portion 4b in the conveying direction D1 and waits at a predetermined position. Next, the control device 21 conveys the workpiece W by pressing the end Wz of the workpiece W with the contact portion 4a so that the workpiece W is positioned at a predetermined position on the die 2. Next, the control device 21 moves the contact portion 4b in the opposite direction to the conveying direction D1 and brings the contact portion 4b into contact with the end Wk of the workpiece W (step S16). Then, while the end face of the workpiece W is sandwiched between the contact portions 4a and 4b, the control device 21 causes the punch 3 to press the workpiece W (step S17). After conveying the workpiece W to a predetermined measurement position, the control device 21 calculates a value related to the shape of the pressed portion of the workpiece W from the detection results of the shape sensor 11 (step S18).

[0062] Next, the control device 21 determines whether the workpiece W has a predetermined shape (step S19). If the workpiece W does not have the predetermined shape (NO in step S19), the control device 21 moves the contact portion 4a in the opposite direction to the conveying direction D1 and makes it wait at a predetermined position. Next, the control device 21 presses the end face Wk of the workpiece W with the contact portion 4b to push back the workpiece W. Next, the control device 21 moves the contact portion 4a in the conveying direction D1 and makes the contact portion 4a contact the end Wz of the workpiece W (step S16), and then repeats the processing from step S17 onwards.

[0063] On the other hand, if the workpiece W has the predetermined shape (YES in step S19) and the next part to be pressed by the punch 3 based on the workpiece transport program is not the upstream surface end Ws (NO in step S20), the control device 21 returns to step S16 and repeats the subsequent processing.

[0064] On the other hand, if the workpiece W has a predetermined shape (YES in step S19) and the next part to be pressed by the punch 3 based on the workpiece transport program is the upstream surface end Ws (YES in step S20), the control device 21 transports the workpiece W using the contact part 4a so that the upstream surface end Ws of the workpiece W is positioned at a predetermined position on the die 2 (step S21).

[0065] The control device 21 causes the suction device 12 of the downstream transport device 15b to suction and hold the workpiece W and retracts the contact portion 4a, and then causes the punch 3 to press the upstream surface end Ws of the workpiece W (step S22). Next, the control device 21 transports the workpiece W to a predetermined measurement position in the opposite direction to the transport direction D1, and then calculates a value related to the shape of the pressed portion of the workpiece W from the detection result by the shape sensor 11 upstream of the die 2 (step S23).

[0066] Next, the control device 21 determines whether the workpiece W has the predetermined shape (step S24). If the workpiece W does not have the predetermined shape (NO in step S24), the control device 21 presses the end Wz of the workpiece W with the contact portion 4a, moves the workpiece W in the conveying direction D1 (step S21), and then repeats the processing from step S22 onwards. On the other hand, if the workpiece W has the predetermined shape (YES in step S24), the control device 21 ends the bending process.

[0067] 12 is a diagram for explaining a method for pressing the upstream surface end Ws of the workpiece W with the punch 3, as shown in steps S8 and S9 of Fig. 10 above. When pressing the surface end Ws of the workpiece W with the punch 3, it is necessary to prevent interference between the contact portion 4a that presses the end Wz and the punch 3.

[0068] As shown in Figure 12, after the contact portion 4a that presses the end portion Wz of the workpiece W is moved above the die 2, the workpiece W is adsorbed and held by the suction device 12 provided on the downstream conveyance device 15b. Then, the contact portion 4a is moved in the opposite direction to the conveyance direction D1 and retracted to a predetermined position. Even when the contact portion 4a is retracted in this way, the position of the workpiece W can be stably maintained by the suction device 12.

[0069] Furthermore, after the contact portion 4a is retracted from the position above the die 2 in the direction opposite to the conveying direction D1, the surface end portion Ws of the workpiece W is pressed by the punch 3. This allows the surface end portion Ws of the workpiece W to be pressed by the punch 3 without causing interference between the contact portion 4a and the punch 3. Note that, as shown in steps 1 and 2 or steps S12 and S13, when the surface end portion Ws of the workpiece W is pressed by the punch 3, the surface end portion Ws is pressed by the punch 3 in the same manner while the workpiece W is being adsorbed by the adsorption device 12 of the upstream conveying device 15a.

[0070] FIG. 13 is a diagram illustrating a method for acquiring values ​​related to the shape of the surface end Ws of the workpiece W, as shown in step S10 of FIG. 10 or step S23 of FIG. 11. As shown in FIG. 13, the surface end Ws of the workpiece W is pressed by the punch 3. Values ​​related to the shape of this surface end Ws cannot be acquired by the downstream shape sensor 11 because the surface end Ws is on the die 2 and falls off the die 2 if it is transported further downstream, resulting in an unstable state. Therefore, after being pressed, the workpiece W is pushed back in the opposite direction of the transport direction D1 by the contact portion 4a or the contact portions 4a and 4b. The workpiece W is then adsorbed by the suction device 12 of the downstream transport device 15b, and the contact portion 4a is retracted in the opposite direction of the transport direction D1. Values ​​related to the shape of the surface end Ws are acquired by the upstream shape sensor 11. In this case, values ​​can be acquired by the shape sensor 11 while the workpiece W is supported by the die 2. This allows the accurate shape of the workpiece W to be obtained. In the description of Figure 13, the workpiece W after pressing is pushed back in the opposite direction of the conveying direction D1 by the contact portion 4a, or by the contact portion 4a and the contact portion 4b, but the workpiece W may also be pushed back in the opposite direction of the conveying direction D1 by adsorbing it to the suction device 12 of the downstream conveying device 15b.

[0071] 14 shows details of the measurement of values ​​relating to the shape shown in another example of FIG. 13 relating to step S10 of FIG. 10 or step S23 of FIG. 11 described above, or step S3 of FIG. 10 or step S14 of FIG. 11, and is a diagram showing a manner in which values ​​relating to the shape of the workpiece W are obtained while the workpiece W is held by the suction device 12.

[0072] As shown in FIG. 14, values ​​relating to the shape of the workpiece W may be acquired by the shape sensor 11 while the workpiece W is held by the suction device 12. By stably holding the workpiece W through support by the suction device 12 and the die 2, it is possible to prevent the workpiece W from shifting in position during acquisition. This makes it possible to obtain an accurate shape of the workpiece W. Note that, in FIG. 14, as an example, the workpiece W is adsorbed only by the suction device 12 of the upstream transport device 15a, but the workpiece W may also be adsorbed by the suction device 12 of the downstream transport device 15b.

[0073] Fig. 15 is a diagram for explaining the deformation units 4h provided on the upstream transfer device 15a and the downstream transfer device 15b. Figs. 16A to 16E are diagrams showing the flow of transport of the workpiece W by the upstream transfer device 15a and the downstream transfer device 15b having the deformation units 4h and the bending process for the upstream surface edge Ws. Figs. 16A to 16E correspond to steps S8 and S9 in Fig. 10 or steps S21 and S22 in Fig. 11. The receiving table 6 is omitted from Figs. 16A to 16E.

[0074] 15, each of the upstream transfer device 15a and the downstream transfer device 15b may have a deformation portion 4h that allows displacement of the contact portions 4a, 4b by deforming only when the contact portions 4a, 4b receive pressure equal to or greater than a specified pressure or pressure from a direction other than along the transfer direction D1 of the workpiece W. The deformation portion 4h may be anything that can deform when the contact portions 4a, 4b receive pressure from the workpiece W, and examples of the deformation portion 4h include a hinge, a spring, and an elastic body. FIG. 15 shows a hinge as an example of the deformation portion 4h.

[0075] The deformation portions 4h are provided between the holding portion 5 and the contact portions 4a, 4b, respectively. The deformation portions 4h deform only when the contact portions 4a, 4b receive a pressure equal to or greater than a specified value or pressure from a direction other than the conveyance direction D1 of the workpiece W, thereby allowing the contact portions 4a, 4b to be displaced. As a result, when the contact portions 4a and 4b press and grip the workpiece W, the contact portions 4a, 4b are displaced only when the contact portions 4a and 4b receive a pressure equal to or greater than a specified value or pressure from a direction other than the conveyance direction D1 of the workpiece W. Therefore, it is possible to prevent overload on the workpiece W and the contact portions 4a, 4b without reducing the positioning accuracy of the workpiece W.

[0076] 16A, the upstream end face Wz of the workpiece W is pressed by the contact portion 4a to transport the workpiece W to a predetermined position, and the downstream receiving table 6 supports the workpiece W. At this time, the control device 21 positions the contact portion 4a so that the bottom surface of the contact portion 4a is located below the top surface of the die 2. The downstream transport device 15b is made to wait at a predetermined position in the transport direction D1.

[0077] Next, as shown in Fig. 16B, the control device 21 moves the contact portion 4a in the conveying direction D1, and when the contact portion 4a comes into contact with the die 2, the deformation portion 4h, which acts as a hinge, opens, displacing the contact portion 4a. At this time, the contact portion 4a rides onto the die 2. As a result, the upstream surface end Ws of the workpiece W, which is to be pressed by the punch 3, is supported by the die 2. After the surface end Ws of the workpiece W is supported by the die 2, the suction device 12 of the downstream conveying device 15b suctions and holds the workpiece W, as shown in Fig. 16C.

[0078] After the workpiece W is sucked by the suction device 12, the contact portion 4a is moved in the opposite direction to the conveyance direction D1 and retracted to a predetermined position, as shown in Fig. 16D. Even when the contact portion 4a is retracted, the position of the workpiece W is stably maintained by the holding by the suction device 12. After the contact portion 4a is retracted, the upstream surface end Ws of the workpiece W is pressed by the punch 3, as shown in Fig. 16E. Note that when the workpiece W is conveyed in the opposite direction to the conveyance direction D1 and the downstream surface end Ws of the workpiece W is bent, as in steps S12 and S13 of Fig. 11, the upstream and downstream processes can be reversed and the process can be performed in the same manner as in Figs. 16A to 16E.

[0079] Fig. 17 is a diagram showing how the receiving table 6 is rotated around a predetermined rotation axis by the receiving table drive device 36. Fig. 18 is a diagram showing how the receiving table 6 is raised and lowered by the receiving table drive device 36. Note that the rollers 6r are omitted from Figs. 17 and 18.

[0080] As shown in FIG. 17, the receiving pedestal 6 on the upstream side in the conveying direction D1 and the receiving pedestal 6 on the downstream side in the conveying direction D1 each have a rotation axis 6k at the end closer to the die 2. The rotation axis 6k is parallel to the extension direction of the die 2. A receiving pedestal drive device 36 is connected to each receiving pedestal 6. The receiving pedestal drive device 36 includes an actuator such as a cylinder, and rotates the receiving pedestal 6 about the rotation axis 6k by pushing and pulling the receiving pedestal 6. Note that, although the receiving pedestal drive devices 36 are provided on both the upstream and downstream receiving pedestals 6, this is not limiting, and the receiving pedestal drive device 36 may be provided on only one of the upstream and downstream receiving pedestals 6.

[0081] When acquiring values ​​relating to the shape of the pressed portion of the workpiece W in step S3, step S6, step S10, step S14, step S18, or step S23, one of the upstream and downstream receiving pedestals 6 supporting the workpiece W is rotated, i.e., moved, to release support by the receiving pedestal 6. Specifically, if the pressed portion of the workpiece W to be acquired is located upstream in the conveyance direction D1, the upstream receiving pedestal 6 is moved by the receiving pedestal drive device 36 to release support by the receiving pedestal 6. Also, if the pressed portion of the workpiece W to be acquired is located downstream in the conveyance direction D1, the downstream receiving pedestal 6 is moved by the receiving pedestal drive device 36 to release support by the receiving pedestal 6. Then, values ​​relating to the shape of the pressed portion of the workpiece W supported by the moved receiving pedestal 6 are acquired by the shape sensor 11. This allows the above acquisition to be performed without pressure from the receiving pedestal 6 being applied to the pressed portion to be acquired, thereby obtaining the accurate shape of the workpiece W.

[0082] When performing the first bending of the workpiece W with the punch 3, the downstream receiving table 6 is moved to a position where it supports the workpiece W, and the upstream receiving table 6 is moved to a position where it does not support the workpiece W, and the workpiece W is pressed by the punch 3.

[0083] 17 in which the receiving table 6 is rotated, a configuration in which the receiving table 6 is raised and lowered by a receiving table drive device 37 as shown in FIG. 18 may be employed. The receiving table drive device 37 includes an actuator such as a cylinder or a motor, and raises and lowers the receiving table 6 by pushing or pulling the receiving table 6 or by rotating a ball screw. When acquiring values ​​related to the shape of the pressed portion of the workpiece W in step S3, step S6, step S10, step S14, step S18, or step S23, one of the receiving tables 6 on the upstream side and the receiving table 6 on the downstream side that support the workpiece W is lowered to release the support by that receiving table 6.

[0084] Fig. 19A is a diagram showing a plurality of rollers 6r that support the workpiece W from below, and Fig. 19B is a diagram showing a state in which the rollers 6r have been moved. Instead of the configuration of Fig. 17 in which the receiving table 6 is rotated, or the configuration of Fig. 18 in which the receiving table 6 is raised and lowered by a receiving table drive device 37, a configuration in which each roller 6r is raised and lowered by a roller drive device 35 shown in Figs. 19A and 19B may be employed. In this case, each roller 6r corresponds to the receiving table.

[0085] As shown in FIG. 19A, a roller drive device 35 is provided for each roller 6r. The roller drive device 35 includes an actuator such as a hydraulic cylinder, a pneumatic cylinder, an electric cylinder, a rack and pinion, or a motor, and moves the roller 6r toward and away from the workpiece W. Each roller 6r can be moved individually to any position by the corresponding roller drive device 35. This makes it possible to move each roller 6r according to the shape of the workpiece W, as shown in FIG. 19B, and to support the workpiece W on each roller 6r. When supporting an arc-shaped workpiece W as shown in FIG. 19B, the movement amount of the roller 6r from its initial position increases as it moves away from the die 2 supporting the workpiece W in the conveying direction D1 and in the direction opposite to the conveying direction D1.

[0086] Fig. 20 is a diagram showing how the downstream roller guide 7 is rotated in the first bending, and Fig. 21 is a diagram showing how the upstream roller guide 7 and the downstream roller guide 7 are rotated.

[0087] As shown in FIG. 20, each of the roller guides 7 on the upstream side in the conveying direction D1 and the roller guides 7 on the downstream side in the conveying direction D1 has a rotation shaft 7k at the end farther from the die 2. The rotation shaft 7k is parallel to the extension direction of the die 2. A roller guide drive device 38 is connected to each roller guide 7. The roller guide drive device 38 includes an actuator such as a cylinder, and rotates the roller guide 7 about the rotation shaft 7k by pushing and pulling the roller guide 7. Note that instead of providing the rotation shaft 7k at the end farther from the die 2 as described above, it may be located at any position along the conveying direction D1 of the roller guide 7.

[0088] After the workpiece W begins to be conveyed by the contact portion 4a in order to perform the first bending, the downstream roller guide 7 is rotated to press the workpiece W from below until the workpiece W is supported by the downstream receiving table 6, as shown in Fig. 20. This not only prevents the workpiece W from contacting the die 2 during conveyance, but also prevents the workpiece W from moving due to inertia when the contact portion 4a presses the end Wz of the workpiece W, and makes it possible to press the workpiece W against the contact portion 4a using its own weight. This prevents the workpiece W from coming off the contact portion 4a during conveyance, improving conveyance accuracy.

[0089] During transport of the workpiece W after it has been supported on the downstream receiving table 6, the upstream and downstream roller guides 7 are rotated so that one end of each roller guide 7 on the die 2 side is positioned higher than the other end, as shown in Fig. 21. This prevents the workpiece W from coming into contact with the die 2 during transport.

[0090] As described above, according to this embodiment, the upstream end Wz of the workpiece W is conveyed in the conveying direction D1 while being pressed by the contact portion 4a of the upstream conveying device, and the receiving table 6 arranged downstream in the conveying direction D1 supports the workpiece W from below so as to conform to the shape of the workpiece W after being pressed by the punch 3. This prevents a decrease in conveying accuracy when conveying the workpiece W to a predetermined position, even if the amount of bending increases during processing, during incremental forming, which obtains a desired shape by repeating conveying and pressing. Therefore, the conveying accuracy relative to the pressing position of the punch 3 is improved compared to a conventional configuration in which the workpiece is pushed by a work pusher provided only upstream in the conveying direction D1. Furthermore, because the process of fixing a support (attachment) to the workpiece W and the process of hooking the holding portion of the moving device to the support are not required, the workpiece W can be conveyed in a simpler manner than in the past.

[0091] (Variation) In addition to the above-described embodiments, the present disclosure can be modified in various ways as follows without departing from the spirit of the present disclosure.

[0092] In the above embodiment, the roller guide 7 is configured to rotate around the rotation axis 7k, but this is not limited to this. For example, the roller guide 7 may be raised and lowered using a motor and a ball screw, or the roller guide 7 may be moved in the conveying direction D1 and the opposite direction.

[0093] Furthermore, in the above embodiment, the receiving table 6 is configured to rotate around the rotation axis 6k, to raise and lower the receiving table 6, or to raise and lower each roller 6r, but this is not limited to this. For example, the receiving table 6 may be configured to move in the conveying direction D1 or the opposite direction using a motor and a ball screw, etc., to move in a direction toward or away from the workpiece. In the case of a configuration in which the receiving table 6 moves in the conveying direction D1 or the opposite direction, values ​​related to the shape of the pressed portion of the workpiece W are obtained after the receiving table 6 is moved in a direction away from the die 2.

[0094] Furthermore, in the above embodiment, the receiving base 6 is provided with a plurality of rollers 6r, but this is not limiting, and the number of rollers 6r may be one.

[0095] Furthermore, in the above embodiment, the upstream conveying device 15a on the upstream side and the downstream conveying device 15b on the downstream side in the work conveying device 100 are configured to be the same, but this is not limited to this, and the configuration of the upstream conveying device 15a and the configuration of the downstream conveying device 15b on the downstream side may be different.

[0096] In the above embodiment, a proximity sensor or a laser distance measuring sensor is used as the distance sensor 10 that detects the distance between the contact portion 4a and the upstream end Wz of the workpiece W and the distance between the contact portion 4b and the downstream end Wk of the workpiece W. However, this is not limiting, and a combination of multiple types of distance sensors 10 may be arranged.

[0097] In addition, in the above embodiment, a receiving platform drive device 36 is connected to each of the upstream receiving platform 6 and the downstream receiving platform 6, but this is not limited to this, and the receiving platform drive device 36 may be connected to only one of the receiving platforms 6.

[0098] In addition, in the above embodiment, the roller guide drive device 38 is connected to each of the upstream roller guide 7 and the downstream roller guide 7, but this is not limited to this, and the roller guide drive device 38 may be connected to only one of the roller guides 7.

[0099] In the above embodiment, the holding unit 5 is moved by the guide rails 8 and 9, but this is not limiting and any mechanism that can move the holding unit 5 in the first orthogonal direction D2 and the second orthogonal direction D3 may be used. For example, a conveyor or a robot such as an articulated robot may be used.

[0100] Furthermore, in the above embodiment, the third drive unit 26c is a drive source such as a motor, but the slide mechanism 31 may be slid along the guide rail 8 manually.

[0101] In addition, in the above embodiment, the first drive unit 26a, the second drive unit 26b, and the third drive unit 26c are motors, and the slide mechanism 31 and the lifting mechanism 32 are ball screws, but they may also be configured with known drive mechanisms such as a hydraulic cylinder, a pneumatic cylinder, an electric cylinder, or a rack and pinion.

[0102] 19A and 19B, the workpiece W is supported by rollers 6r driven by roller drive device 35, but this is not limited to this. A configuration combining a cradle 6 rotated by a cradle drive device 36 and rollers 6r driven by the roller drive device 35 may be used as a cradle 6. Also, a configuration combining a cradle 6 raised and lowered by a cradle drive device 37 and rollers 6r driven by the roller drive device 35 may be used as a cradle 6.

[0103] Note that the configuration for achieving control by the control device 21 is not limited to the above-described exemplary configuration. The functions disclosed herein can be performed using circuits or processing circuits, including general-purpose processors, special-purpose processors, integrated circuits, ASICs (Application Specific Integrated Circuits), conventional circuits, and / or combinations thereof, configured or programmed to perform the disclosed functions. A processor is considered a processing circuit or circuit because it includes transistors and other circuits. In this disclosure, a circuit, unit, or means is hardware that performs the recited functions or hardware programmed to perform the recited functions. The hardware may be hardware disclosed herein or other known hardware that is programmed or configured to perform the recited functions. When the hardware is a processor, which is considered a type of circuit, the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and / or processor.

[0104] According to the present disclosure, the upstream conveying device conveys the workpiece in the conveying direction while pressing the upstream end of the workpiece, and the receiving table located downstream in the conveying direction supports the workpiece from below so as to conform to the shape of the workpiece after pressing by the punch. This prevents a decrease in conveying accuracy when conveying the workpiece to a predetermined position, even if the amount of bending increases during processing, during incremental forming, which involves repeated conveying and pressing to obtain a desired shape. Therefore, the conveying accuracy relative to the punch pressing position is improved compared to conventional configurations in which the workpiece is pushed by a work pusher located only upstream in the conveying direction. Furthermore, because the process of fixing a support (attachment) to the workpiece and the process of hooking the holding portion of the moving device to the support are not required, the workpiece can be conveyed in a simpler manner than conventional methods.

[0105] In the above disclosure, a downstream conveying device arranged downstream in the conveying direction of the workpiece may be moved in the conveying direction, and while the upstream conveying device presses the upstream end of the workpiece in the conveying direction, the upstream conveying device may be moved in the conveying direction, and the downstream conveying device may be moved to bring the downstream end of the workpiece in the conveying direction into contact with the downstream conveying device, thereby intermittently conveying the workpiece in the conveying direction.

[0106] According to the above configuration, the conveying accuracy does not decrease even when the workpiece is re-bent.

[0107] In the above disclosure, the target position to which the upstream conveying device is to be moved may be stored in a memory unit, the target position of the upstream conveying device may be acquired from the memory unit, the upstream conveying device may be moved based on the target position of the upstream conveying device, and the workpiece may be conveyed in the conveying direction.

[0108] According to the above configuration, the workpiece can be steadily transported by the specified transport amount.

[0109] In the above disclosure, information regarding the distance between the upstream conveying device and the end of the workpiece may be detected, and the operation of the press brake and the operation of the upstream conveying device may be changed according to the information regarding the distance.

[0110] According to the above configuration, it is possible to avoid molding defects that may occur when a workpiece is transported with a gap between the upstream transport device and the workpiece.

[0111] In the above disclosure, the upstream conveying device or the downstream conveying device arranged downstream of the press brake in the conveying direction may have an adsorption device that adsorbs the workpiece, and the adsorption device of one of the upstream conveying device and the downstream conveying device may adsorb and hold the workpiece, and the other of the upstream conveying device and the downstream conveying device may be moved in a direction away from the press brake to release the pressure on the end of the workpiece.

[0112] According to the above configuration, interference between the punch and the conveying device that presses the end of the workpiece can be prevented.

[0113] In the above disclosure, each of the upstream conveying device and the downstream conveying device arranged downstream of the press brake in the conveying direction includes a contact portion that contacts an end face of the workpiece and a deformation portion that deforms when the contact portion receives a pressure equal to or greater than a specified pressure or a pressure from a direction other than along the conveying direction of the workpiece, thereby allowing displacement of the contact portion; and before the punch presses the surface end portion of the workpiece upstream or downstream in the conveying direction, the contact portion of one of the upstream conveying device and the downstream conveying device is moved in a direction approaching the press brake to convey the workpiece, and when the contact portion contacts the die, the deformation portion deforms, thereby displacing the contact portion and causing it to ride up onto the die, and the workpiece is adsorbed and held by an adsorption device included in the other of the upstream conveying device and the downstream conveying device, and the one conveying device is retracted in a direction away from the press brake.

[0114] According to the above configuration, when the contact portion contacts the die, the deformation portion deforms, displacing the contact portion, thereby transporting the end of the workpiece to a position above the die. In addition, by using the suction device to suction and hold the workpiece, one of the transport devices can be retracted, thereby preventing interference between the one transport device and the punch.

[0115] In the above disclosure, after pressing the surface end portion of the workpiece on one of the upstream and downstream sides in the conveying direction with the punch, the workpiece may be moved in one of the upstream and downstream directions in the conveying direction of the workpiece by a conveying device arranged on one or both of the upstream and downstream sides in the conveying direction of the workpiece, and the shape of the surface end portion of the workpiece pressed by the punch may be measured.

[0116] According to the above configuration, the workpiece can be stably supported by the die and measured.

[0117] In the above disclosure, after pressing the surface end portion of the workpiece on one of the upstream or downstream sides in the conveying direction with the punch, the workpiece is adsorbed by an adsorption device possessed by a conveying device arranged on the other of the upstream or downstream sides in the conveying direction of the workpiece, and the workpiece is moved in the direction of the upstream or downstream side in the conveying direction of the workpiece, and the workpiece is adsorbed and held by an adsorption device possessed by the other conveying device, and the shape of the surface end portion of the workpiece pressed by the punch may be measured.

[0118] According to the above configuration, defects in the forming of the workpiece can be detected.

[0119] In the above disclosure, a receiving table arranged downstream in the conveying direction, and a receiving table arranged upstream in the conveying direction and supporting the workpiece from below so as to conform to the shape of the workpiece after it has been pressed by the punch, may be moved in a direction toward or away from the workpiece depending on the shape of the workpiece.

[0120] According to the above configuration, it is possible to support a workpiece in accordance with various shapes of the workpiece.

[0121] In the above disclosure, one of the upstream receiving table and the downstream receiving table may be moved to release the support of the workpiece by that receiving table, and the shape of the portion of the workpiece that was supported by the moved receiving table and that was pressed by the punch may be measured.

[0122] According to the above configuration, it is possible to prevent a moment from being applied to the part of the workpiece to be measured by the pedestal, thereby preventing the workpiece from being bent by the pedestal, and therefore enabling accurate measurements of the shape of the workpiece.

[0123] In the above disclosure, the downstream receiving table may be moved to a position where it supports the workpiece, and the upstream receiving table may be moved to a position where it does not support the workpiece, and the workpiece may be transported.

[0124] According to the above configuration, by retracting the upstream receiving table, it is possible to prevent the upstream receiving table from interfering with the flat portion of the workpiece upstream in the conveying direction (the portion that has not yet been pressed by the punch).

[0125] In the above disclosure, a roller guide that is positioned downstream of the press brake in the conveying direction, supports the work from below, and moves vertically, rotates around an axis parallel to the extension direction of the die, or moves in the conveying direction and the opposite direction to the conveying direction may be moved or rotated to press the work from below with the roller guide, bring the end of the work into contact with the upstream conveying device, and convey the work.

[0126] According to the above configuration, after the upstream-side conveying device and the downstream-side conveying device start conveying the workpiece, the downstream-side roller guide can be moved to press the workpiece from below until the workpiece is supported on the downstream-side receiving table. This not only prevents the workpiece from contacting the die during conveyance, but also presses the workpiece against the upstream-side conveying device, preventing the workpiece from slipping off the pressure applied by the upstream-side conveying device.

[0127] In the above disclosure, each of the roller guides, which are arranged upstream and downstream of the press brake in the conveying direction, support the work from below, and move in the vertical direction, rotate around an axis parallel to the extension direction of the die, or move in the conveying direction and the opposite direction to the conveying direction, may be moved or rotated to position one end of each roller guide on the press brake side higher than the other end, thereby conveying the work.

[0128] According to the above configuration, after the workpiece is supported on the downstream support, each of the upstream and downstream roller guides is rotated so that one end of each roller guide on the press brake side is positioned higher than the other end, thereby preventing the workpiece from contacting the die during transport.

[0129] In the above disclosure, the workpiece transport device may further include a memory unit that stores a target position to which the upstream transport device is to be moved, and the control device may acquire the target position of the upstream transport device from the memory unit and cause the transport drive device to move the upstream transport device based on the target position of the upstream transport device.

[0130] In the above disclosure, the work transport device may further include a distance sensor that detects information regarding the distance between the upstream transport device and the end of the work, and the control device may change the operation of the press brake and the operation of the upstream transport device according to the information regarding the distance detected by the distance sensor.

[0131] In the above disclosure, the workpiece transport device may further include a downstream transport device arranged downstream of the press brake in the transport direction of the workpiece, and each of the upstream transport device and the downstream transport device may include a contact portion that contacts the end face of the workpiece, a deformation portion that deforms when the contact portion receives pressure greater than a specified value or pressure from a direction other than along the transport direction of the workpiece, thereby allowing displacement of the contact portion, and a connection portion that is connected to the transport drive device while holding the deformation portion.

[0132] In the above disclosure, the contact portion of the upstream conveying device may be provided with a positioning portion having a shape corresponding to a positioned portion provided at an upstream end of the workpiece in the conveying direction.

[0133] According to the above configuration, by engaging the positioning portion with the positioned portion, the workpiece can be positioned with high precision in the intersecting direction that intersects with the conveying direction.

[0134] In the above disclosure, the workpiece transport device may further include a downstream transport device arranged downstream of the press brake in the transport direction of the workpiece, and an adsorption device provided on the upstream transport device or the downstream transport device that adsorbs and holds the workpiece.

[0135] In the above disclosure, the workpiece transport device may further include an arc-shaped receiving platform that is arranged upstream and downstream of the press brake in the transport direction and supports the workpiece from below.

[0136] In the above disclosure, the receiving table may have a plurality of rollers that can move toward the workpiece and away from the workpiece, and the workpiece transport device may further include a roller drive device provided corresponding to each of the plurality of rollers and that moves the rollers.

[0137] In the above disclosure, the workpiece transport device may further include a table drive device that rotates the table around a predetermined rotation axis.

[0138] In the above disclosure, the workpiece transport device may further include a cross-direction platform drive device that moves the platform in the transport direction or in a cross direction that crosses the transport direction.

[0139] In the above disclosure, the workpiece transport device may further include roller guides that are arranged upstream and downstream of the press brake in the transport direction, support the workpiece, and rotate around a predetermined rotation axis, move in the intersecting direction, or move in the transport direction. [Explanation of symbols]

[0140] 1. Press brake 2 Die 3 Punch 4a Upstream contact area 4b Downstream contact area 4h Deformed part 4i Positioning part 5 Holding part 6 Cradle 6r Laura 7 Roller guide 10 Distance Sensor 11 Shape sensor 12 Adsorption device 15a Upstream transport device 15b Downstream conveying device 21 Control device 22 ROM 23 RAM 24 HDD 26 Conveyor drive device 35 Roller drive unit 36 Cradle drive unit 100 Work transport device D1 Conveying direction D2 First orthogonal direction D3 Second orthogonal direction double work Wh Positioned part Wk Downstream end of workpiece Ws Surface edge of workpiece Wz Upstream end of workpiece

Claims

1. A workpiece conveying device that conveys a workpiece during bending processing of the workpiece by a press brake including a die supporting the workpiece and a punch disposed above the die and pressing the workpiece, An upstream conveying device arranged upstream of the press brake in the conveying direction of the work; A downstream conveying device that is disposed downstream of the press brake and contacts an end surface of the workpiece; a transport drive device that moves the upstream transport device in the transport direction; a receiving table disposed downstream in the conveying direction and configured to support the workpiece from below in a manner conforming to the shape of the workpiece after it has been pressed by the punch; A control device, Each of the upstream conveying device and the downstream conveying device includes a contact portion that contacts an end face of the workpiece, a deformation portion that deforms when the contact portion receives pressure equal to or greater than a specified pressure or pressure from a direction other than the conveying direction of the workpiece, thereby allowing displacement of the contact portion, and a connection portion that is connected to the conveying drive device while holding the deformation portion, The control device controls the conveying drive device to move the upstream conveying device in the conveying direction while pressing the upstream end of the workpiece in the conveying direction against the upstream conveying device before or after the bending process, thereby intermittently conveying the workpiece in the conveying direction.

2. A storage unit that stores a target position to which the upstream transport device is moved, The workpiece transport device according to claim 1 , wherein the control device acquires a target position of the upstream transport device from the storage unit, and causes the transport drive device to move the upstream transport device based on the target position of the upstream transport device.

3. Further, a distance sensor is provided for detecting information regarding a distance between the upstream conveying device and an end of the workpiece, 3. The workpiece transportation device according to claim 1, wherein the control device changes an operation of the press brake and an operation of the upstream transportation device in accordance with information regarding the distance detected by the distance sensor.

4. A work transport device as described in any one of claims 1 to 3, wherein the contact portion of the upstream transport device or the downstream transport device is provided with a positioning portion having a shape corresponding to a positioned portion provided at the upstream or downstream end of the work in the transport direction.

5. The workpiece transport device according to claim 1 , further comprising a suction device provided in the upstream transport device or the downstream transport device for suctioning and holding the workpiece.

6. 6. The work transport device according to claim 1, further comprising an arc-shaped support platform arranged on the upstream side and downstream side of the press brake in the transport direction, the support platform supporting the work from below.

7. The receiving table has a plurality of rollers that are movable in a direction toward the workpiece and in a direction away from the workpiece, The workpiece transport device according to claim 6 , further comprising a roller driving device provided corresponding to each of the plurality of rollers for moving the rollers.

8. 8. The workpiece transport device according to claim 6, further comprising a table drive device for rotating the table about a predetermined rotation axis.

9. The workpiece transport device according to claim 6 , further comprising a cross-direction support drive device that moves the support in the transport direction or in a cross direction that crosses the transport direction.

10. 10. The work transport device according to claim 1, further comprising roller guides arranged upstream and downstream of the transport direction with respect to the press brake, supporting the work and rotating about a predetermined rotation axis, moving in a direction intersecting the transport direction, or moving in the transport direction.

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