Workpiece transport method, workpiece transport device, and workpiece transport program

Abstract

To provide a workpiece conveyance method, a workpiece conveyance device and a workpiece conveyance program which can enhance conveyance accuracy from conventional ones, and can convey workpiece by a simple method.SOLUTION: A workpiece conveyance method for conveying workpiece when the workpiece is bent by a press brake having a die supporting the workpiece and a punch which is arranged above the die and presses the workpiece supported by the die presses a surface end on one of the upstream side and the downstream side in workpiece conveyance direction by the punch, then moves the workpiece in one direction of the upstream side and the downstream side in the workpiece conveyance direction, and measures the shape of the surface end of the workpiece pressed by the punch.SELECTED DRAWING: Figure 3

Description

Technical Field

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

Background Art

[0002] Conventionally, a bending device for bending a plate material is known. For example, Patent Document 1 discloses a bending device that presses a workpiece against a bag gauge with a workpiece pusher when transporting the workpiece to a predetermined position. Further, Patent Document 2 discloses a bending device that fixes supports to the upstream end and the downstream end in the transport direction of the workpiece, hooks the holding portion of the upstream moving device on one support, and hooks the holding portion of the downstream moving device on the other support. In this bending device, the workpiece is transported by moving each moving device while each holding portion is hooked on the support.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the bending device of Patent Document 1 that presses a workpiece to a predetermined position with a workpiece pusher, particularly in sequential forming processing where conveyance and pressing are repeated to obtain a desired shape, when the amount of bending increases due to processing, there is a problem that the conveyance accuracy when transporting to the predetermined position decreases. Further, in the bending device of Patent Document 2, steps of fixing supports to the workpiece and hooking the holding portion of the moving device on the support occur. Therefore, it has been desired to transport the workpiece by a simpler method.

[0005] Therefore, the purpose of this disclosure is to provide a workpiece transport method, a workpiece transport device, and a workpiece transport program that can transport workpieces in a simple manner and have higher transport accuracy than conventional methods. [Means for solving the problem]

[0006] The workpiece transport method of this disclosure is a workpiece transport method for transporting a workpiece during bending processing of a workpiece using a press brake comprising a die that supports the workpiece and a punch positioned above the die that presses the workpiece supported by the die, wherein before or after the bending processing, the upstream transport device, positioned upstream of the press brake in the transport direction of the workpiece, presses the upstream end of the workpiece in the transport direction while moving the upstream transport device in the transport direction, and the workpiece is supported from below by a support stand positioned downstream in the transport direction so as to conform to the shape of the workpiece after being pressed by the punch, thereby intermittently transporting the workpiece in the transport direction.

[0007] The workpiece transport device of this disclosure transports a workpiece during bending of the workpiece using a press brake, which comprises a die that supports the workpiece and a punch positioned above the die that presses the workpiece, and comprises an upstream transport device positioned upstream of the press brake in the workpiece transport direction, a transport drive device that moves the upstream transport device in the transport direction, a support base positioned downstream in the transport direction that supports the workpiece from below in accordance with the shape of the workpiece after being pressed by the punch, and a control device, wherein 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 process, thereby intermittently transporting the workpiece in the transport direction.

[0008] The workpiece transport program of this disclosure is a workpiece transport program to be executed by a computer in a workpiece transport device that transports a workpiece when bending the workpiece with a press brake comprising a die that supports the workpiece and a punch positioned above the die that presses the workpiece supported by the die, wherein the computer functions as a transport control means that, before or after the bending process, moves the upstream transport device, which is positioned upstream of the press brake in the transport direction of the workpiece, while pressing the upstream end of the workpiece in the transport direction with the upstream transport device, and supports the workpiece from below on a support positioned downstream in the transport direction so as to conform to the shape of the workpiece after being pressed by the punch, thereby intermittently transporting the workpiece in the transport direction. [Effects of the Invention]

[0009] According to this disclosure, it is possible to provide a workpiece transport method, a workpiece transport device, and a workpiece transport program that can transport workpieces in a simple manner while achieving higher transport accuracy than conventional methods. [Brief explanation of the drawing]

[0010] [Figure 1] This is a plan view showing a bending system including a plurality of workpiece transport devices according to one embodiment of the present disclosure. [Figure 2] Figure 1 is a perspective view of the workpiece transport device as seen from the downstream side in the transport direction. [Figure 3] Figure 1 is a perspective view of the workpiece transport device as seen from the upstream side in the transport direction. [Figure 4] This is a control system block in a workpiece transfer device. [Figure 5] This is a schematic diagram showing the upstream conveying device that presses the workpiece during the initial bending process. [Figure 6] This is a schematic diagram showing the upstream and downstream conveying devices that press the workpiece during rebending. [Figure 7]It is a diagram showing a state where the positioning parts of each contact part are engaged with the positioned part of the workpiece. [Figure 8A] It is a side view showing the arrangement of the distance sensors. [Figure 8B] It is a front view showing the arrangement of the distance sensors. [Figure 9] It is a front view showing the arrangement of the distance sensors according to another example. [Figure 10] It is a flowchart showing the process flow of bending. [Figure 11] It is a flowchart showing the process flow of bending. [Figure 12] It is a diagram for explaining a method of pressing the surface end of a workpiece with a punch. <000​​​​​​​​​​​​​​​​​​​​​​​​​It is a diagram showing a mode in which a receiving base is rotated around a predetermined rotation axis by a receiving base driving device. [Figure 18] It is a diagram showing a mode in which a receiving base is moved up and down by a receiving base driving device. [Figure 19A] It is a diagram showing a plurality of rollers that support a workpiece from below. [Figure 19B] It is a diagram showing a mode in which the roller is moved. [Figure 20] It is a diagram showing a mode in which a downstream roller guide is rotated. [Figure 21] It is a diagram showing a mode in which upstream and downstream roller guides are rotated.

Embodiment for Carrying Out the Invention

[0011] Hereinafter, a workpiece transfer method, a workpiece transfer device, and a workpiece transfer program according to an embodiment of the present disclosure will be described with reference to the drawings. The workpiece transfer method, the workpiece transfer device, and the workpiece transfer program described below are merely one embodiment of the present disclosure. Therefore, the present disclosure is not limited to the following embodiments, and additions, deletions, and changes are possible without departing from the spirit of the present disclosure.

[0012] FIG. 1 is a plan view showing a bending processing system 200 including a plurality of workpiece transfer devices 100 according to an embodiment of the present disclosure. FIG. 2 is a perspective view of the workpiece transfer device 100 in FIG. 1 as viewed from the downstream side in the transfer direction, and FIG. 3 is a perspective view of the workpiece transfer device 100 in FIG. 1 as viewed from the upstream side in the transfer direction. In the following description, the transfer direction of the workpiece W transferred by the workpiece transfer device 100 is defined as D1, and two directions orthogonal to the transfer direction D1 are defined as the first orthogonal direction D2 and the second orthogonal direction D3. The second orthogonal direction D3 is, for example, the vertical direction and is the direction in which the workpiece W is pressed. Note that the first orthogonal direction D2 corresponds to the crossing direction.

[0013] The bending system 200 bends a flat workpiece W into a predetermined shape by repeatedly performing the processes of pitch-transporting the workpiece W in the transport direction D1 and pressing the workpiece W from a second orthogonal direction D3. As shown in Figure 1, the bending system 200 includes a press brake 1 which includes a die 2 which is a lower die and a punch 3 which is an upper die, and a plurality of workpiece transport devices 100. Figure 1 illustrates four workpiece transport devices 100 arranged in a line in the first orthogonal direction D2, but there may be one workpiece transport device 100 or five or more.

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

[0015] The workpiece conveying device 100 will now be described. The configuration of each workpiece conveying device 100 is the same. The workpiece conveying device 100 comprises an upstream conveying device 15a including a contact portion 4a and a holding portion 5, a downstream conveying device 15b including a contact portion 4b and a holding portion 5, a support base 6, a roller guide 7, a guide rail 8, and a guide rail 9.

[0016] The upstream conveying device 15a is positioned upstream of the conveying direction D1 relative to the press brake 1. The contact parts 4a and 4b are formed in a block shape and are made of, for example, resin. Contact part 4a contacts the upstream end Wz of the workpiece W. Contact part 4a presses the end Wz without gripping it. Contact part 4a is held by a holding part 5. The holding part 5 is connected to the conveying drive device 26 shown in Figure 4. The holding part 5 corresponds to the connection between the contact part 4a and the conveying drive device 26 and is made of, for example, metal. The holding part 5 rotates around an axis parallel to the first orthogonal direction D2. When conveying the flat workpiece W to the die 2 before bending is started, the side of the contact part 4a and contact part 4b that is positioned at a longer distance from 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 positioned downstream of the press brake 1 in the conveying direction D1. 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 the holding portion 5 of the downstream conveying device 15b. This holding portion 5 is connected to the 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 makes surface contact with the upstream end Wz of the workpiece W. At this time, the contact portion 4a makes surface contact with the upstream end face of the flat workpiece W that intersects with the face to be pressed by the punch 3. Accordingly, in this disclosure, the end Wz includes the above-mentioned 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 workpiece W (hereinafter sometimes referred to as the initial bending), if the shape does not reach the desired level, an additional bending (hereinafter sometimes referred to as rebending) may be performed by pressing again with the punch 3. In this case, the workpiece W that has undergone the initial bending is pressed and transported by the contact parts 4a and 4b. In this case, since the workpiece W that has undergone the initial bending is arc-shaped, the contact part 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 said end face. The contact part 4b also 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 said end face. Therefore, in this disclosure, end Wz further includes the ridge that constitutes the upstream end face of the workpiece W. The end Wk also includes the downstream end face of the workpiece W and the ridge that constitutes the said end face.

[0020] The support base 6 supports the workpiece W while it is being pressed or while its shape is being measured. For example, two support bases 6 are provided on the upstream side in the transport direction D1, and for example, two are provided on the downstream side in the transport direction D1, but there may be one on each side, or there may be three or more. Each support base 6 on the upstream side is provided at a predetermined interval in the first orthogonal direction D2, and each support base 6 on the downstream side is provided at a predetermined interval in the first orthogonal direction D2.

[0021] The support base 6 has a plurality of rollers 6r. The upper edge of the support base 6 is formed in an arc shape. Each roller 6r is arranged in an arc shape on the upper edge of the support base 6 at a predetermined interval in the conveying direction D1. The rollers 6r are pivotally supported between two plate materials that constitute the support base 6 and are arranged at a predetermined interval in the first orthogonal direction D2, and are rotatable about 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 plurality of rollers 6r matches the contour shape of the workpiece W after bending. The support base 6 moves in a direction approaching the workpiece W and in a direction away from the workpiece W, for example, in a second orthogonal direction D3. Alternatively, instead of moving in a direction approaching the workpiece W and away from the workpiece W, the support base 6 may rotate about a predetermined axis of rotation parallel to the first orthogonal direction D2. Alternatively, instead of the rollers 6r being pivotally supported between two plate materials, 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 during transport. For example, two roller guides 7 are provided on the upstream side in the transport direction D1, and for example, two are provided on the downstream side in the transport direction D1, but there may be one on each side, or three or more. The downstream end of the upstream roller guides 7 is located downstream of the downstream end of the upstream support base 6. The upstream end of the downstream roller guides 7 is located upstream of the upstream end of the downstream support base 6. Each of the upstream roller guides 7 is provided at a predetermined distance from each other in the first orthogonal direction D2, and each of the downstream roller guides 7 is provided at a predetermined distance 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 constitutes the roller guide 7 and is pivotally supported between two plate materials arranged at a predetermined distance in a first orthogonal direction D2, and is rotatable about 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 about a predetermined axis of rotation parallel to the first orthogonal direction D2. The roller guide may have any shape, but is preferably flat.

[0024] Guide rails 9 are provided on both the upstream and downstream sides of the transport direction D1. Guide rails 9 extend in the transport direction D1. Guide rails 9 support the holding portion 5 from below and guide the holding portion 5 in the transport direction D1 and in the opposite direction of the transport direction D1. As a result, contact portions 4a and 4b move in the transport direction D1 and in the opposite direction of the transport direction D1.

[0025] Guide rails 8 are provided on both the upstream and downstream sides of the transport direction D1. Guide rails 8 extend in the first orthogonal direction D2. Guide rails 8 support guide rail 9 from below and guide guide rail 9 and the holding part 5 supported on guide rail 9 in the first orthogonal direction D2. As a result, contact parts 4a and 4b move in the first orthogonal direction D2.

[0026] As shown in Figures 2 and 3, a distance sensor 10 is provided on 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, it means that the contact portion 4a is in contact with the end Wz. The distance sensor 10 can be, for example, a proximity sensor, a laser distance sensor, or an image sensor. When an image sensor is used as the distance sensor 10, the sizes of the ends Wz and Wk of the workpiece W in the image obtained by the image sensor can be acquired as distance information (without directly calculating the distance). Thus, distance information is not limited to direct distance information, but also includes information that allows for indirect estimation of distance.

[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 Figure 3, the workpiece W is shown with a dashed line to clearly show each component of the conveying device 100.

[0028] The workpiece transfer device 100 is equipped with a plurality of shape sensors 11. Each shape sensor 11 is positioned near the die 2. Specifically, each shape sensor 11 is positioned below the workpiece W supported by the die 2. Each shape sensor 11 is positioned upstream of the transfer direction D1 and at a predetermined interval in the first orthogonal direction D2, and also at a predetermined interval downstream of the transfer direction D1 and in the first orthogonal direction D2. The shape sensors 11 are, for example, proximity sensors, laser distance 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 conveying device 15a and the downstream conveying device 15b are each provided with a suction device 12. The suction device 12 suctions and holds the workpiece W. Examples of suction methods for the suction device 12 include air suction using suction cups and electromagnetic suction.

[0030] Figure 4 is a block diagram showing the control system of the workpiece transfer device 100. As shown in Figure 4, the workpiece transfer device 100 comprises a control unit 20, a pressing drive device 25, a transfer drive device 26, a roller drive device 35, a support base drive device 36, and a roller guide drive device 38.

[0031] The control unit 20 comprises 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 the target positions to which the contact parts 4a and 4b should be moved when the workpiece W is transported. The target positions are determined based on the contour R information of the workpiece W to be molded, and define each position in the transport direction D1 of the workpiece W and the height corresponding to that position. The RAM 23 is used as the processing area of ​​the control device 21. The control device 21 corresponds to the transport control means, and the ROM 22, RAM 23, and HDD 24 correspond to the storage units.

[0032] The HDD24 stores a workpiece transport program for operating the workpiece transport device 100 of this disclosure. The workpiece transport program may be received from an external device and stored in the HDD24, or it may be read from a computer-readable recording medium (e.g., DVD-ROM and USB flash memory) on which the workpiece transport program is recorded and stored in the HDD24.

[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 also controls the operation of the pressing drive device 25 so that the punch 3 is separated from the workpiece W after pressing against it. 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 parts 4a and 4b move in the transport direction D1, the first orthogonal direction D2, and the second orthogonal direction D3 based on the target position. Details of the transport drive device 26 will be described later. The control device 21 also controls the operation of the suction device 12 so that it attracts and holds the workpiece W.

[0035] The control device 21 controls the operation of the roller drive device 35 so that the rollers 6r of the support base 6 move toward the workpiece W and toward the workpiece W. The control device 21 also controls the operation of the support base drive device 36 so that the support base 6 rotates around a predetermined axis of rotation. The control device 21 also controls the operation of the roller guide drive device 38 so that the roller guide 7 rotates around a predetermined axis of rotation. The roller drive device 35 and the support base drive device 36 may both be provided, or only one of them may be provided.

[0036] The control device 21 receives distance information between the contact portion 4a and the upstream end Wz of the workpiece W from the distance sensor 10 on the upstream side in the transport direction D1. The control device 21 also receives distance information between the contact portion 4b and the downstream end Wk of the workpiece W from the distance sensor 10 on the downstream side in the transport direction D1. The control device 21 modifies the operation of the punch 3 and the transport drive device 26 according to the distances detected by each distance sensor 10. Specifically, for example, if the distances detected by each distance sensor 10 exceed an acceptable 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 transport drive device 26.

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

[0038] Figure 5 is a schematic diagram showing the upstream conveying device 15a that presses the workpiece W during the initial bending. Figure 6 is a schematic diagram showing the upstream conveying device 15a and the downstream conveying device 15b immediately before and immediately after pressing the workpiece W during rebending. Note that the downstream conveying device 15b and the conveying drive device 26 that drives the downstream conveying device 15b are not shown in Figure 5.

[0039] Since the configuration of the transport drive unit 26 that drives the upstream transport device 15a is the same as the configuration of the transport drive unit 26 that drives the downstream transport device 15b, the configuration of the transport drive unit 26 that drives the upstream transport device 15a will be described as representative below. The transport drive unit 26 comprises a first drive unit 26a, a second drive unit 26b, a third drive unit 26c, and a fourth drive unit 26d. A sliding mechanism 31 and a lifting mechanism 32 are connected to the holding unit 5. The lifting 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 lifting mechanism 32 is raised and lowered by the first drive unit 26a. As a result, the holding unit 5 is raised and lowered, and the contact unit 4a is raised and lowered accordingly.

[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 slide mechanism 31 slides along the guide rail 9 due to the second drive unit 26b. As a result, the holding part 5 slides along the guide rail 9, and the contact part 4a moves in the transport direction D1 and in the opposite direction of the transport direction D1. The third drive unit 26c is also a drive source such as a motor and slides the slide mechanism 31 and the guide rail 9 along the guide rail 8. As a result, the holding part 5 slides along the guide rail 8, and the contact part 4a moves in the first orthogonal direction D2.

[0041] Furthermore, the fourth drive unit 26d is a drive source such as a motor, which rotates the rotating shaft provided in the holding unit 5 around an axis parallel to the first orthogonal direction D2. As a result, the suction device 12 rotates around an axis parallel to the first orthogonal direction D2. The suction device 12 rotates according to the shape of the workpiece W and picks up the workpiece W.

[0042] When transporting the workpiece W for the initial bending is initiated, the first drive unit 26a, the second drive unit 26b, and the third drive unit 26c move the contact portion 4a to a predetermined position according to the instructions of the control device 21. As a result, the contact portion 4a is positioned opposite the end portion Wz of the workpiece W at a distance from it in the transport direction D1. From this state, the second drive unit 26b moves the contact portion 4a in the transport direction D1 according to the instructions of the control device 21, bringing it into contact with the end portion Wz of the workpiece W, and then presses the end portion Wz of the workpiece W, moving the workpiece W to a position defined in the workpiece transport program. In this way, the workpiece W is transported in the transport direction D1.

[0043] On the other hand, when transporting the workpiece W to perform rebending, the first drive unit 26a, the second drive unit 26b, and the third drive unit 26c move the contact parts 4a and 4b to predetermined positions according to the instructions of the control device 21. During rebending, since the workpiece W has a contour R, the contact parts 4a and 4b also move in the second orthogonal direction D3. As a result, the contact part 4a is positioned opposite the end Wz of the workpiece W at a position spaced apart from the end Wz in the transport direction D1, and the contact part 4b is positioned opposite 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 part 4a in the transport direction D1 according to the instructions of the control device 21 to bring it into contact with the end Wz of the workpiece W, and then presses the end Wz of the workpiece W against the contact part 4a, moving the workpiece W to the position defined in the workpiece transport program. Next, the second drive unit 26b moves the contact portion 4b in the opposite direction to the transport direction D1 according to the instructions of the control device 21, bringing it into contact with the end portion Wk of the workpiece W at the position defined in the workpiece transport program. As a result, the end portion Wz of the workpiece W is pressed by the contact portion 4a and the end portion Wk is brought into contact with the contact portion 4b. This allows the workpiece W to be transported while being positioned with high precision by the contact portions 4a and 4b.

[0044] Figure 7 shows the state in which the positioning parts 4i of the contact parts 4a and 4b are engaged with the positioning part Wh of the workpiece W.

[0045] As shown in Figure 7, positioning portions Wh may be provided at the upstream end Wz and the downstream end Wk of the workpiece W in the transport direction D1. Multiple positioning portions Wh may be provided at the ends Wz and Wk of the workpiece W. The positioning portions Wh are formed, for example, in a convex shape outward from the ends Wz and Wk.

[0046] On the other hand, positioning parts 4i are provided at the contact parts 4a and 4b, respectively. By engaging the positioning parts 4i with the part to be positioned Wh, the workpiece W can be positioned with high precision in the first orthogonal direction D2.

[0047] The number and arrangement of the positioning sections 4i are determined according to the number and arrangement of the positioned sections Wh of the workpiece W. The positioning sections 4i are formed, for example, in a concave shape. Although the positioned sections Wh are shown as convex and the positioning sections 4i as concave, the design is not limited to this, and the positioned sections Wh may be concave and the positioning sections 4i as convex. Furthermore, the positioning sections 4i may have a multi-stage concave shape and the positioned sections Wh may have a multi-stage convex shape. In addition, the positioning sections 4i may have a multi-stage convex shape and the positioned sections Wh may have a multi-stage concave shape.

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

[0049] As shown in Figures 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 that intersects with the surface of the contact portion 4a that faces 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 distance measuring sensors. When the distance sensor 10 is a proximity sensor, each distance sensor 10 is arranged at a different height in order to increase the detection width in the height direction of the contact position of the end Wz of the workpiece W with respect to 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 provided. Also, when multiple distance sensors 10 are arranged in the height direction, if there is no area in the height direction detection width of the sensor 10 where the workpiece W cannot be detected, it is not necessarily required to provide them on both sides of the contact portion 4a.

[0050] As an alternative to the distance sensor 10, a laser distance measuring sensor, distance sensor 10a, may be used. As shown in Figure 9, multiple distance sensors 10a are provided on the contact portion 4a. Each distance sensor 10a is provided on the surface that intersects with the surface of the contact portion 4a that faces 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. In order to increase the detection width in the height direction of the contact position of the end Wz of the workpiece W with respect to the contact portion 4a, each distance sensor 10a is arranged so that the irradiation height of its light source is different. By arranging each distance sensor 10 in this way, it is possible to detect the distance between the contact portions 4a, 4b and the ends Wz, Wk of the workpiece W, or the distance between the contact portions 4a, 4b and the ends Wz, Wk of the workpiece W, regardless of where the ends Wz, Wk of the workpiece W approach the contact portions 4a, 4b. Note that if detection is possible for the required detection width in the height direction with a single distance sensor 10, only one distance sensor 10 may be provided. Furthermore, when multiple distance sensors 10 are arranged in the height direction, if there is no area within the detection width of the sensor 10 in the height direction where the workpiece W cannot be detected, it is not necessarily required to provide them on both sides of the contact portion 4a.

[0051] Figures 10 and 11 are flowcharts showing the bending process. As shown in Figure 10, the control device 21 presses the workpiece W with the contact portion 4a of the upstream conveying device 15a so that the downstream surface edge Ws of the flat plate-shaped workpiece W before forming is positioned at a predetermined position on the die 2, thereby conveying the workpiece W from the upstream side to the downstream side (step S1). At this time, the control device 21 moves the downstream support base 6 to a position that supports the workpiece W, and moves the upstream support base 6 to a position that does not support the workpiece W. The control device 21 may change the operation of the punch 3 and the conveying drive device 26, for example, stop them, according to the distance detected by the distance sensor 10 during the conveying 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 against the contact portion 4a of the upstream conveying device 15a, 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 this disclosure, the surface edge Ws refers to the interference regions on the surface of the workpiece W on the upstream and downstream sides where the punch 3 and the contact portions 4a and 4b may interfere when pressed by the punch 3.

[0053] Next, the control device 21 presses the end Wz of the workpiece W with the contact portion 4a of the upstream conveying device 15a to measure the shape of the pressed downstream surface end Ws, and after conveying the workpiece W to a predetermined measurement position, it 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 S3). Subsequently, the control device 21 presses the end Wz of the workpiece W with the contact portion 4a and conveys the workpiece W to a predetermined position (step S4). The control device 21 presses the workpiece W with the punch 3 (step S5). Then, the control device 21 presses the end Wz of the workpiece W with the contact portion 4a of the upstream conveying device 15a and conveys the workpiece W to a predetermined measurement position, and after calculating a value related to the shape of the pressed portion of the workpiece W from the detection result by the shape sensor 11 (step S6).

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

[0055] The control device 21, with the workpiece W held in place by the suction device 12 of the downstream transport device 15b, retracts the contact portion 4a and then presses the punch 3 against 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 of 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 on the upstream side of the die 2 (step S10).

[0056] Next, the control device 21 determines whether the workpiece W has a predetermined shape (step S11). In this case, the control device 21 can determine whether the workpiece W has a predetermined shape based on the calculated value relating 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 terminates the bending process.

[0057] Conversely, if the workpiece W does not have the predetermined shape (NO in step S11), the control device 21 performs a rebend on the workpiece W as described below. The following description will focus on the case where rebend is performed on the downstream surface edge Ws, the upstream surface edge Ws, and the entire surface of the workpiece W (excluding the downstream and upstream surface edges Ws). However, rebend may be omitted depending on the shape measurement results.

[0058] First, the control device 21 presses the end Wk of the workpiece W, which is 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 of the transport direction D1. Then, the contact portion 4a of the upstream transport device 15a transports 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). The control device 21 may change the operation of the punch 3 and the transport drive device 26, for example, stop them, according to the distance detected by the distance sensor 10 during the transport and bending of the workpiece W.

[0059] If the area of ​​the workpiece W to be pressed during the revending process is the downstream surface edge Ws of the workpiece W, the control device 21 causes the workpiece W to be held by the suction device 12 of the upstream transport device 15a and retracts the contact portion 4b, and then causes the punch 3 to press the downstream surface edge Ws of the workpiece W (step S13). Next, the control device 21 transports the workpiece W to a predetermined measurement position by the contact portion 4a, 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 does not have a predetermined shape (NO in step S15), the control device 21 pushes the workpiece W back with the contact part 4b (step S12), and then repeats the process 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 rebending is the area between the downstream surface edge Ws and the upstream surface edge Ws of the workpiece W, the control device 21 moves the contact portion 4b in the transport direction D1 and waits in a predetermined position. Next, the control device 21 presses the edge Wz of the workpiece W with the contact portion 4a so that the workpiece W is positioned in a predetermined position on the die 2 and transports the workpiece W. Next, the control device 21 moves the contact portion 4b in the opposite direction of the transport direction D1 and brings the contact portion 4b into contact with the edge Wk of the workpiece W (step S16). Then, with the end face of the workpiece W sandwiched between the contact portion 4a and the contact portion 4b, the control device 21 presses the workpiece W against the punch 3 (step S17). After transporting 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 result by 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 a predetermined shape (NO in step S19), the control device 21 moves the contact portion 4a in the opposite direction to the transport direction D1 and places it in a predetermined position. Next, the control device 21 presses the end face Wk of the workpiece W with the contact portion 4b and pushes the workpiece W back. Next, the control device 21 moves the contact portion 4a in the transport direction D1 and brings the contact portion 4a into contact with the end Wz of the workpiece W (step S16), and then repeats the process from step S17 onwards.

[0063] On the other hand, if the workpiece W has a predetermined shape (YES in step S19) and the part to be pressed by the punch 3 next 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] In contrast, if the workpiece W has a predetermined shape (YES in step S19) and the portion to be pressed by the punch 3 next according to the workpiece transport program is the upstream surface edge Ws (YES in step S20), the control device 21 transports the workpiece W using the contact portion 4a so that the upstream surface edge Ws of the workpiece W is positioned at a predetermined location on the die 2 (step S21).

[0065] The control device 21 causes the workpiece W to be held by the suction device 12 of the downstream transport device 15b and the contact portion 4a to retract, and then causes the punch 3 to press the upstream surface edge 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 of 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 on the upstream side of the die 2 (step S23).

[0066] Next, the control device 21 determines whether the workpiece W has taken on a 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 part 4a and moves the workpiece W in the transport direction D1 (step S21), and then repeats the process from step S22 onwards. On the other hand, if the workpiece W has taken on the predetermined shape (YES in step S24), the control device 21 terminates the bending process.

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

[0068] As shown in Figure 12, after the contact portion 4a that presses the end Wz of the workpiece W is moved onto the die 2, the workpiece W is held in place by the suction device 12 provided on the downstream conveying device 15b. Then, the contact portion 4a is moved in the opposite direction to the conveying 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 held by the suction device 12.

[0069] Furthermore, after retracting the contact portion 4a from its position above the die 2 in the opposite direction to the transport direction D1, the surface edge Ws of the workpiece W is pressed with the punch 3. This allows the surface edge Ws of the workpiece W to be pressed with 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 pressing the surface edge Ws of the workpiece W with the punch 3, the same procedure is followed, with the workpiece W being held in suction by the suction device 12 of the upstream transport device 15a, while the surface edge Ws is pressed with the punch 3.

[0070] Figure 13 is a diagram illustrating a method for obtaining values ​​related to the shape of the surface edge Ws of the workpiece W, as shown in step S10 of Figure 10 or step S23 of Figure 11. As shown in Figure 13, the surface edge Ws of the workpiece W is pressed with the punch 3. The values ​​related to the shape of this surface edge Ws cannot be obtained by the downstream shape sensor 11 because the surface edge Ws is on the die 2 and will fall off the die 2 if transported further downstream, resulting in an unstable state. Therefore, after pressing, the workpiece W is pushed back in the opposite direction of the transport direction D1 by the contact part 4a, or contact parts 4a and 4b. Then, the workpiece W is picked up by the suction device 12 of the downstream transport device 15b, and with the contact part 4a retracted in the opposite direction of the transport direction D1, the values ​​related to the shape of the surface edge Ws are obtained by the shape sensor 11 provided on the upstream side. In this case, the values ​​can be obtained by the shape sensor 11 while the workpiece W is supported by the die 2. This makes it possible to obtain the accurate shape of the workpiece W. In the explanation in Figure 13, the workpiece W after pressing is pushed back in the opposite direction of the transport direction D1 by the contact part 4a, or by contact parts 4a and 4b. However, the workpiece W may also be pushed back in the opposite direction of the transport direction D1 by using the suction device 12 of the downstream transport device 15b to pick up the workpiece W.

[0071] Figure 14 shows details of the measurement of shape-related values ​​shown in step S10 of Figure 10 or step S23 of Figure 11, or in step S3 of Figure 10 or step S14 of Figure 11, and illustrates a method of acquiring shape-related values ​​of the workpiece W while the workpiece W is held by the suction device 12.

[0072] As shown in Figure 14, 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 with support from the suction device 12 and die 2, displacement of the workpiece W during acquisition can be prevented. This makes it possible to obtain the accurate shape of the workpiece W. In Figure 14, as an example, the workpiece W is picked up only by the suction device 12 of the upstream transport device 15a, but the workpiece W may also be picked up by the suction device 12 of the downstream transport device 15b.

[0073] Figure 15 is a diagram illustrating the deformation section 4h provided in the upstream conveying device 15a and the downstream conveying device 15b. Figures 16A to 16E are diagrams illustrating the flow of conveying the workpiece W and bending the upstream surface edge Ws by the upstream conveying device 15a and the downstream conveying device 15b, which have the deformation section 4h. Figures 16A to 16E correspond to steps S8 and S9 in Figure 10, or steps S21 and S22 in Figure 11. Note that the support base 6 is omitted in Figures 16A to 16E.

[0074] As shown in Figure 15, each of the upstream conveying device 15a and the downstream conveying device 15b may have a deformable part 4h that deforms only when the contact parts 4a and 4b are subjected to a pressure exceeding a specified amount or pressure from a direction other than the conveying direction D1 of the workpiece W, thereby allowing displacement of the contact parts 4a and 4b. The deformable part 4h can be anything that can deform when the contact parts 4a and 4b are subjected to pressure from the workpiece W, and examples include hinges, springs, and elastic bodies. Figure 15 illustrates a hinge as an example of the deformable part 4h.

[0075] The deformable portion 4h is provided between the holding portion 5 and the contact portions 4a and 4b. The deformable portion 4h deforms only when the contact portions 4a and 4b are subjected to pressure exceeding a specified level or pressure from a direction other than that along the transport direction D1 of the workpiece W, thereby allowing displacement of the contact portions 4a and 4b. As a result, when the workpiece W is pressed and gripped by the contact portions 4a and 4b, the contact portions 4a and 4b are displaced only when subjected to pressure exceeding a specified level or pressure from a direction other than that along the transport direction D1 of the workpiece W. Therefore, it is possible to suppress overloading of the workpiece W and the contact portions 4a and 4b without reducing the positioning accuracy of the workpiece W.

[0076] As shown in Figure 16A, the contact portion 4a presses against the upstream end face Wz of the workpiece W to transport the workpiece W to a predetermined position, and the downstream support base 6 supports the workpiece W. At this time, the control device 21 positions the contact portion 4a such that its lower surface is below the upper surface of the die 2. The downstream transport device 15b is kept waiting at a predetermined position in the transport direction D1.

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

[0078] After the workpiece W is picked up by the suction device 12, the contact portion 4a is moved in the opposite direction to the transport direction D1 and retracted to a predetermined position, as shown in Figure 16D. Even after the contact portion 4a is retracted, the position of the workpiece W is stably maintained by the holding of the suction device 12. After the contact portion 4a is retracted, the upstream surface end Ws of the workpiece W is pressed with the punch 3, as shown in Figure 16E. Note that if the workpiece W is transported in the opposite direction to the transport direction D1 and the downstream surface end Ws of the workpiece W is bent, as in steps S12 and S13 of Figure 11, the upstream and downstream processes in Figures 16A to 16E can be reversed and the process can be carried out in the same manner.

[0079] Figure 17 shows how the support base 6 is rotated around a predetermined rotation axis by the support base drive device 36. Figure 18 shows how the support base 6 is raised and lowered by the support base drive device 36. Note that the roller 6r is omitted in Figures 17 and 18.

[0080] As shown in Figure 17, each of the support bases 6 on the upstream side in the transport direction D1 and the support base 6 on the downstream side in the transport direction D1 has a rotating shaft 6k at the end closest to the die 2. The rotating shaft 6k is parallel to the extending direction of the die 2. A support base drive device 36 is connected to each support base 6. The support base drive device 36 includes an actuator such as various cylinders, and rotates the support base 6 around the rotating shaft 6k by pushing and pulling it. Although support base drive devices 36 are provided on both the upstream and downstream support bases 6, the device is not limited to this arrangement, and a support base drive device 36 may be provided on only one of the support bases 6.

[0081] 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 support bases 6, either the upstream or downstream support base 6, that supports the workpiece W is rotated, i.e., moved to release support from that support base 6. Specifically, if the pressed portion of the workpiece W to be acquired is located upstream in the transport direction D1, the upstream support base 6 is moved by the support base drive device 36 to release support from that support base 6. If the pressed portion of the workpiece W to be acquired is located downstream in the transport direction D1, the downstream support base 6 is moved by the support base drive device 36 to release support from that support base 6. Then, the shape sensor 11 acquires values ​​related to the shape of the pressed portion of the workpiece W that was supported by the moved support base 6. This allows the acquisition to be performed without pressure from the support base 6 on the pressed portion to be acquired, thereby obtaining the accurate shape of the workpiece W.

[0082] When performing the initial bending of the workpiece W with the punch 3, the downstream support base 6 is moved to a position that supports the workpiece W, while the upstream support base 6 is moved to a position that does not support the workpiece W, and the workpiece W is pressed with the punch 3.

[0083] Instead of the configuration shown in Figure 17 in which the support base 6 is rotated, a configuration in which the support base 6 is raised and lowered by a support base drive device 37 may be adopted as shown in Figure 18. The support base drive device 37 includes, for example, various cylinders or actuators such as motors, and raises and lowers the support base 6 by pushing and pulling or rotating a ball screw. When obtaining values ​​related to the shape of the pressing portion of the workpiece W in step S3, step S6, step S10, step S14, step S18, or step S23, either the upstream support base 6 or the downstream support base 6 that supports the workpiece W is lowered to release the support from that support base 6.

[0084] Figure 19A shows multiple rollers 6r supporting the workpiece W from below, and Figure 19B shows the rollers 6r in a moved state. Instead of the configuration in Figure 17 in which the support base 6 is rotated, or the configuration in Figure 18 in which the support base 6 is raised and lowered by the support base drive device 37, a configuration in which each roller 6r is raised and lowered by the roller drive device 35 shown in Figures 19A and 19B may be adopted. In this case, each roller 6r corresponds to a support base.

[0085] As shown in Figure 19A, a roller drive unit 35 is provided for each roller 6r. The roller drive unit 35 includes actuators such as hydraulic cylinders, pneumatic cylinders, electric cylinders, rack and pinion systems, and motors, and moves the rollers 6r in the direction toward the workpiece W and in the direction toward away from the workpiece W. Each roller 6r can be individually moved to any position by the corresponding roller drive unit 35. This allows each roller 6r to be moved according to the shape of the workpiece W, as shown in Figure 19B, so that the workpiece W is supported by each roller 6r. When supporting an arc-shaped workpiece W as shown in Figure 19B, the amount of movement of the roller 6r from its initial position increases as it moves away from the die 2 supporting the workpiece W in the transport direction D1 and in the direction opposite to the transport direction D1.

[0086] Figure 20 shows the configuration in which the downstream roller guide 7 is rotated during the initial bending. Figure 21 shows the configuration in which both the upstream and downstream roller guides 7 are rotated.

[0087] As shown in Figure 20, each of the roller guides 7 on the upstream side in the conveying direction D1 and the roller guide 7 on the downstream side in the conveying direction D1 has a rotation axis 7k at the end furthest from the die 2. The rotation axis 7k is parallel to the extending 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 actuators such as various cylinders, and rotates the roller guide 7 around the rotation axis 7k by pushing and pulling it. Note that the rotation axis 7k may be located at any position along the conveying direction D1 of the roller guide 7, instead of being located at the end furthest from the die 2 as described above.

[0088] To initiate the initial bending, after the contact portion 4a starts transporting the workpiece W, the downstream roller guide 7 is rotated as shown in Figure 20 to press the workpiece W from below until the workpiece W is supported by the downstream support base 6. This prevents the workpiece W from contacting the die 2 during transport, prevents the workpiece W from moving due to inertia when the contact portion 4a presses against the end Wz of the workpiece W, and allows the workpiece W to be pressed against the contact portion 4a using its own weight. As a result, the workpiece W is prevented from coming off the contact portion 4a during transport, and the transport accuracy can be improved.

[0089] During transport of the workpiece W after it has been supported by the downstream support base 6, as shown in Figure 21, each of the upstream and downstream roller guides 7 is rotated so that one end of each roller guide 7 on the die 2 side is positioned higher than the other end. 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 pressed by the contact portion 4a of the upstream conveying device while the workpiece W is conveyed in the conveying direction D1, and the workpiece W is supported from below by the support base 6 located downstream of the conveying direction D1 so as to conform to the shape of the workpiece W after being pressed by the punch 3. As a result, in sequential forming processes in which the desired shape is obtained by repeating conveying and pressing, the conveying accuracy when conveying the workpiece W to a predetermined position does not decrease even if the amount of bending increases due to the processing. Therefore, the conveying accuracy with respect to the pressing position of the punch 3 is improved compared to the conventional configuration in which the workpiece is pushed by a workpiece pusher provided only on the upstream side of the conveying direction D1. In addition, since there is no need for the process of fixing a support (attachment) to the workpiece W and the process of hooking the holding part of the moving device onto the support, it is possible to convey the workpiece W in a simpler way than in the conventional method.

[0091] (modified version) In addition to the embodiments described above, this disclosure can be modified in various ways without departing from its essence.

[0092] In the above embodiment, the roller guide 7 is configured to rotate around the rotation axis 7k, but the invention is not limited to this configuration. 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 support base 6 is rotated around the rotation axis 6k, the support base 6 is raised and lowered, or each roller 6r is raised and lowered, but the system is not limited to these configurations. For example, the support base 6 may be moved in the transport direction D1 and its opposite direction using a motor and a ball screw, moving it in a direction closer to or further away from the workpiece. In the case where the support base 6 is moved in the transport direction D1 and its opposite direction, values ​​related to the shape of the pressing portion of the workpiece W are obtained after the support base 6 has been moved away from the die 2.

[0094] Furthermore, although the above embodiment provides multiple rollers 6r on the support base 6, the invention is not limited to this, and there may be only one roller 6r.

[0095] Furthermore, in the above embodiment, the configuration of the upstream conveying device 15a and the downstream conveying device 15b on the upstream side of the workpiece conveying device 100 are the same, but the configuration of the upstream conveying device 15a and the downstream conveying device 15b may be different.

[0096] Furthermore, in the above embodiment, a proximity sensor or a laser distance measuring sensor was used as the distance sensor 10 for detecting 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, the invention is not limited to this, and multiple types of distance sensors 10 may be arranged in combination.

[0097] Furthermore, in the above embodiment, the support base drive device 36 was connected to both the upstream support base 6 and the downstream support base 6, but the invention is not limited to this, and the support base drive device 36 may be connected to only one of the support bases 6.

[0098] Furthermore, in the above embodiment, the roller guide drive unit 38 is connected to both the upstream roller guide 7 and the downstream roller guide 7, but the invention is not limited to this, and the roller guide drive unit 38 may be connected to only one of the roller guide 7.

[0099] Furthermore, in the above embodiment, the holding part 5 was moved by guide rails 8 and 9, but the mechanism is not limited to this, and any mechanism that can move the holding part 5 in the first orthogonal direction D2 and the second orthogonal direction D3 is acceptable. For example, it could be a conveyor or a robot such as an articulated robot.

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

[0101] Furthermore, 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 composed of known drive mechanisms such as hydraulic cylinders, pneumatic cylinders, electric cylinders, and rack and pinion systems.

[0102] Furthermore, while Figures 19A and 19B above show the workpiece W being supported by rollers 6r driven by a roller drive device 35, the system is not limited to this. A support base 6 can be configured by combining a support base 6 that rotates with a support base drive device 36 and rollers 6r driven by the roller drive device 35, and this support base 6 can be used. Alternatively, a support base 6 can be configured by combining a support base 6 that moves up and down with a support base drive device 37 and rollers 6r driven by the roller drive device 35, and this support base 6 can be used.

[0103] The configuration for realizing control by the control device 21 is not limited to the configuration exemplified above. The functions disclosed herein can be performed using circuits or processing circuits, including general-purpose processors, dedicated 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 enumerated functions, or hardware programmed to perform the enumerated functions. The hardware may be hardware disclosed herein, or other known hardware that is programmed or configured to perform the enumerated functions. If the hardware is a processor, which is considered a type of circuit, then the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and / or the processor.

[0104] According to this disclosure, the upstream end of the workpiece is pressed against the upstream conveying device while it is being conveyed in the conveying direction, and the workpiece is supported from below by a support stand located downstream in the conveying direction so as to conform to the shape of the workpiece after it has been pressed by the punch. As a result, in sequential forming processes in which the desired shape is obtained by repeatedly conveying and pressing, the conveying accuracy when conveying the workpiece to a predetermined position does not decrease even if the amount of bending increases due to the processing. Therefore, the conveying accuracy with respect to the punch pressing position is improved compared to conventional configurations in which the workpiece is pushed by a workpiece pusher provided only on the upstream side in the conveying direction. Furthermore, since there is no need for the process of fixing a support (attachment) to the workpiece and the process of hooking the holding part of the moving device onto the support, it is possible to convey the workpiece in a simpler way than in conventional methods.

[0105] In the above disclosure, the downstream conveying device, which is positioned downstream of the conveying direction of the workpiece, may be moved in the conveying direction, the upstream conveying device may be moved while the upstream end of the workpiece in the conveying direction is pressed by the upstream conveying device, 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] Following the above configuration, the transport accuracy will not decrease even when the workpiece is bent.

[0107] In the above disclosure, the target position for moving the upstream conveying device may be stored in a storage unit, the target position of the upstream conveying device may be obtained from the storage 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] Following the above configuration, the workpiece can be reliably transported in the specified 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 upstream conveying device may be changed according to the distance information.

[0110] By following the above configuration, it is possible to avoid molding defects that occur due to the workpiece being transported while a gap exists between the upstream transport device and the workpiece.

[0111] In the above disclosure, the upstream conveying device or the downstream conveying device located downstream of the press brake in the conveying direction has a suction device for adsorbing the workpiece, and the workpiece may be adsorbed and held by the suction device of one of the conveying devices, the upstream conveying device or the downstream conveying device, and the other conveying device may be moved away from the press brake to release the pressure on the end of the workpiece.

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

[0113] In the above disclosure, each of the upstream conveying device and the downstream conveying device, which is positioned downstream of the press brake in the conveying direction, includes a contact portion that contacts the end face of the workpiece and a deformable portion that deforms when subjected to a pressure greater than a specified amount or a pressure from a direction other than that along the conveying direction of the workpiece, thereby allowing displacement of the contact portion. Before the punch presses the upstream or downstream surface end of the workpiece in the conveying direction, the contact portion of one of the conveying devices, the upstream conveying device and the downstream conveying device, moves the one conveying device toward the press brake while positioning the lower surface of the contact portion below the upper surface of the die, thereby conveying the workpiece. When the contact portion contacts the die, the deformable portion deforms, displacing the contact portion and causing it to ride up onto the die. The workpiece is then held by a suction device of the other conveying device, the upstream conveying device and the downstream conveying device, and the one conveying device is moved 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 and allowing the end of the workpiece to be transported to a position on the die. In addition, by using a suction device to hold the workpiece by suction, one of the transport devices can be retracted, thereby preventing interference between that transport device and the punch.

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

[0116] Following the above configuration, measurements can be taken while the workpiece is supported and stabilized by the die.

[0117] In the above disclosure, after pressing one of the surface edges of the workpiece, either the upstream or downstream side in the transport direction, with the punch, the workpiece may be moved in the direction of the upstream or downstream side of the transport direction by a suction device of a transport device located on the other side of the transport direction, and the workpiece may be held by a suction device of the transport device located on the other side, and the shape of the surface edge of the workpiece pressed by the punch may be measured.

[0118] Following the above configuration, defects in the molding of the workpiece can be detected.

[0119] In the above disclosure, the support stand positioned downstream in the conveying direction, and the support stand positioned upstream in the conveying direction, which supports the workpiece from below in accordance with the shape of the workpiece after pressing by the punch, may be moved in a direction toward the workpiece or toward the workpiece, depending on the shape of the workpiece.

[0120] According to the above configuration, the workpiece can be supported according to its various shapes.

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

[0122] Following the above configuration, it is possible to avoid the support base acting as a moment on the part of the workpiece to be measured. This prevents the workpiece from being bent by the support base, and therefore allows for accurate measurement of the workpiece's shape.

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

[0124] According to the above configuration, by retracting the upstream support base, it is possible to prevent the upstream support base from interfering with the flat plate-shaped portion (the portion not yet pressed by the punch) on the upstream side in the transport direction of the workpiece.

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

[0126] According to the above configuration, after the upstream and downstream conveying devices begin conveying the workpiece, the downstream roller guide can be moved to press the workpiece from below until it is supported by the downstream support base. This prevents the workpiece from coming into contact with the die during conveying, and also allows the workpiece to be pressed against the upstream conveying device, preventing it from being dislodged from the pressure applied by the upstream conveying device.

[0127] In the above disclosure, the roller guides, which are positioned upstream and downstream of the press brake in the conveying direction, support the workpiece from below and move vertically, rotate around an axis parallel to the extending direction of the die, or move in the conveying direction and the opposite direction of the conveying direction, may be moved or rotated so that one end of each roller guide on the press brake side is positioned above the other end, and the workpiece is conveyed.

[0128] According to the above configuration, after the workpiece is supported on the downstream support base, 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. This prevents the workpiece from coming into contact with the die during transport.

[0129] In the above disclosure, the workpiece transfer device further comprises a storage unit that stores a target position for moving the upstream transfer device, and the control device may obtain the target position of the upstream transfer device from the storage unit and cause the transfer drive unit to move the upstream transfer device based on the target position of the upstream transfer device.

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

[0131] In the above disclosure, the workpiece conveying device further comprises a downstream conveying device arranged downstream of the press brake in the conveying direction of the workpiece, and each of the upstream conveying device and the downstream conveying device may include a contact portion that contacts the end face of the workpiece, a deformable portion that deforms when subjected to a pressure exceeding a specified amount or a pressure from a direction other than that along the conveying direction of the workpiece, thereby allowing displacement of the contact portion, and a connecting portion that holds the deformable portion and is connected to the conveying drive device.

[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 positioning portion provided at the upstream end of the workpiece in the conveying direction.

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

[0134] In the above disclosure, the workpiece conveying device may further include a downstream conveying device positioned downstream of the press brake in the conveying direction of the workpiece, and a suction device provided on the upstream conveying device or the downstream conveying device for suctioning and holding the workpiece.

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

[0136] In the above disclosure, the support base has a plurality of rollers that can move toward the workpiece and toward the workpiece, and the workpiece transport device is provided corresponding to each of the plurality of rollers and may further include a roller drive device for moving the rollers.

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

[0138] In the above disclosure, the workpiece transport device may further include a cross-direction support drive device for moving the support in the transport direction or in a cross-direction intersecting the transport direction.

[0139] In the above disclosure, the workpiece transport device may further include roller guides arranged upstream and downstream of the press brake in the transport direction, which 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 Dies 3 punches 4a Upstream contact area 4b Downstream contact area 4h deformed part 4i Positioning section 5 Holding part 6. Support stand 6r Laura 7 Roller Guide 10 Distance Sensor 11 Shape Sensor 12 Adsorption device 15a Upstream conveying device 15b Downstream conveying device 21 Control device 22 ROM 23 RAM 24 HDD 26. Transport drive device 35 Roller drive system 36. Support stand drive device 100 Workpiece Transfer Device D1 Conveying direction D2 First orthogonal direction D3 Second orthogonal direction Double job Wh Positioned part Wk workpiece downstream end Ws Workpiece Surface Edge Wz workpiece upstream end

Claims

1. A workpiece transport method for transporting a workpiece during bending of a workpiece using a press brake, the press brake comprising a die that supports the workpiece and a punch positioned above the die that presses against the workpiece supported by the die, The upstream conveying device, positioned upstream of the press brake in the conveying direction of the workpiece, presses the upstream side of the workpiece in the conveying direction while moving the upstream conveying device in the conveying direction. Alternatively, the downstream conveying device, positioned downstream of the press brake in the conveying direction of the workpiece, presses the downstream side of the workpiece in the conveying direction while moving the downstream conveying device in the opposite direction to the conveying direction. A workpiece transport method in which, after pressing one of the surface edges of the workpiece, either upstream or downstream in the transport direction, with the punch, the workpiece is moved in either the upstream or downstream direction in the transport direction, and the shape of the surface edge of the workpiece pressed by the punch is measured. In measuring the shape of the surface edge of the workpiece pressed by the punch, The workpiece is picked up by a suction device of a transport device located on the other side of the transport direction of the workpiece, either upstream or downstream, and the workpiece is moved in one of the directions of the transport direction of the workpiece. The other transfer device is positioned to hold the workpiece by adsorption, and the shape of the surface edge of the workpiece pressed by the punch is measured. Workpiece transport method.

2. The downstream conveying device is moved in the conveying direction, While the upstream conveying device presses the workpiece on the upstream side in the conveying direction, the upstream conveying device is moved in the conveying direction. The downstream conveying device is moved to bring the downstream side of the workpiece in the conveying direction into contact with the downstream conveying device, thereby conveying the workpiece in the conveying direction. Alternatively, the upstream conveying device may be moved in the opposite direction to the conveying direction. While the downstream conveying device presses the downstream side of the workpiece in the conveying direction, the downstream conveying device is moved in the opposite direction to the conveying direction. The upstream conveying device is moved to bring the upstream side of the workpiece in the conveying direction into contact with the upstream conveying device, thereby conveying the workpiece in the opposite direction to the conveying direction. The workpiece transport method according to claim 1.

3. In measuring the shape of the surface edge of the workpiece pressed by the punch, A conveying device positioned on either the upstream or downstream side of the workpiece in the conveying direction, or both, moves the workpiece in either the upstream or downstream side of the conveying direction, and measures the shape of the surface edge of the workpiece pressed by the punch. The workpiece transport method according to claim 1 or 2.

4. The storage unit stores the target position for moving the upstream conveying device or the downstream conveying device. The target position of the upstream conveying device or the downstream conveying device is obtained from the storage unit. A workpiece transport method according to any one of claims 1 to 3, wherein the upstream transport device or the downstream transport device is moved based on the target position of the upstream transport device or the downstream transport device, and the workpiece is transported in the transport direction or in the opposite direction to the transport direction.

5. Information regarding the distance between the upstream conveying device or the downstream conveying device and the workpiece is detected. A workpiece transport method according to any one of claims 1 to 4, wherein the operation of the press brake, or the operation of the upstream transport device or the downstream transport device is changed according to the information regarding the distance.

6. The workpiece is held by the suction device of either the upstream or downstream conveying device, A workpiece transport method according to any one of claims 3 to 5, wherein the other of the upstream transport device or the downstream transport device is moved away from the press brake to release the pressure on the workpiece.

7. The upstream conveying device or the downstream conveying device includes a contact portion that contacts the end face of the workpiece, and a deformable portion that deforms when the contact portion is subjected to a pressure exceeding a specified amount or a pressure from a direction other than the conveying direction of the workpiece, thereby allowing displacement of the contact portion. Before pressing the upstream or downstream surface edge of the workpiece in the transport direction with the punch, The workpiece is transported by moving one of the transport devices, either the upstream transport device or the downstream transport device, in a direction toward the press brake, while positioning the lower surface of the contact portion of the transport device below the upper surface of the die. When the contact portion comes into contact with the die, the deformation portion deforms, causing the contact portion to displace and ride up onto the die. The workpiece transport method according to any one of claims 1 to 6, wherein the one transport device is retracted in a direction away from the press brake.

8. A workpiece transport method according to any one of claims 1 to 7, wherein a support stand positioned downstream in the transport direction, or a support stand positioned upstream in the transport direction, is moved in a direction toward the workpiece or toward the workpiece, depending on the shape of the workpiece.

9. Move either the upstream support or the downstream support to release the support the support provides to the workpiece. The workpiece transport method according to claim 8, wherein the shape of the portion of the workpiece that was pressed by the punch and was supported by one of the support bases is measured.

10. Move the downstream support to a position that supports the workpiece, and move the upstream support to a position that does not support the workpiece. Alternatively, the upstream support base may be moved to a position that supports the workpiece, and the downstream support base may be moved to a position that does not support the workpiece. A workpiece transport method according to claim 8 or 9, for transporting the aforementioned workpiece.

11. A workpiece transport method according to any one of claims 8 to 10, wherein a roller guide, positioned upstream or downstream in the transport direction with respect to the press brake and supporting the workpiece from below, is moved or rotated to press the workpiece from below with the roller guide, thereby bringing the workpiece into contact with the upstream transport device or the downstream transport device, and transporting the workpiece.

12. A workpiece transport method according to any one of claims 8 to 11, wherein a roller guide, which is positioned upstream or downstream in the transport direction relative to the press brake and supports the workpiece from below, is moved or rotated so that one end of each roller guide on the press brake side is positioned above the other end, and the workpiece is transported.

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