JP7390227B2 - Gripping device and bending system - Google Patents

Description

The present invention relates to a regripping device for regripping a workpiece by a robot hand of a bending robot, and a bending system for bending a workpiece.

The bending system includes a press brake that bends a workpiece, and a bending robot that assists in bending the workpiece. The bending robot includes a multi-joint robot arm and a robot hand that is detachably attached to the tip of the robot arm and holds a workpiece. Here, when bending a normal-sized or large-sized workpiece, a suction-type robot hand having a plurality of vacuum pads that suctions the front or back surface of the workpiece is mainly used as the robot hand. When bending a strip-shaped workpiece, a gripping type robot hand having a gripper (workpiece clamp) that grips the end of the workpiece is mainly used as the robot hand. Further, the bending system shown in Patent Document 1 includes, in addition to a press brake and a bending robot, a regripping device (work support device in Patent Document 1) for regripping a workpiece with a robot hand. A brief description of the configuration of the prior art regripping device is as follows.

In front of the press brake, a pair of left and right carriages (left and right moving members in Patent Document 1) are provided so as to be movable in the left and right direction. Each carriage is provided with an elevating body (vertical moving member in Patent Document 1) so as to be movable up and down. Each elevating body has, on its upper side, a workpiece placement section (workpiece support section in Patent Document 1) on which a normal-sized or large-sized workpiece in a horizontal position is placed. In addition, a work clamp is provided in front of each elevating body to grip an end of a vertically-positioned strip-shaped work. Each work clamp includes a fixed clamp claw (fixed clamp jaw in Patent Document 1) provided on the front of each elevating body so as to protrude inward in the left-right direction, and a fixed clamp claw provided on the front of each elevating body that moves toward and away from the fixed clamp claw. It has a movable clamp jaw (referred to as a movable clamp jaw in Patent Document 1) that is provided so as to be movable in the direction.

Therefore, during a series of bending operations on normal-sized or large-sized workpieces, the bending robot places the workpiece in a horizontal position on a pair of workpiece placement sections, and the suction-type robot hand moves between the front and back surfaces of the workpiece. Re-grasp. In addition, during a series of bending processes for a strip-shaped workpiece, a pair of workpiece clamps grips the end of the workpiece in a vertical position, and a gripping robot hand grips the workpiece between one end of the workpiece and the other end. Make a change.

In addition to Patent Document 1, there is a prior art related to the present invention shown in Patent Document 2.

JP 2015-13303 Publication JP2016-112667A

By the way, when bending a small workpiece, a gripping type robot hand is mainly used as the robot hand, as in the case of bending a strip-shaped workpiece. After the bending flange is formed on the end of the small workpiece, the bending flange formed end of the small workpiece cannot be gripped by the workpiece clamp. Moreover, it is also impossible to stably place a small workpiece on the workpiece mounting section in a state in which the end portion of the small workpiece protrudes from the workpiece mounting section. That is, during a series of bending operations on a small workpiece, it is not possible to change the gripping type of the robot hand between the end portion of the small workpiece where the bending flange has not been formed and the end portion where the bending flange has been formed. As a result, there is a problem in that the bending system cannot complete a series of bending operations on small workpieces.

Therefore, in order to solve the above-mentioned problem, the present invention makes it possible to grasp the bending flange-formed end of a small workpiece while avoiding interference with the bending flange formed at the end of the small workpiece. The purpose of the present invention is to provide a regripping device and a bending system.

The regripping device according to the first embodiment includes a pair of left and right carriages (movable frames) provided in front of a press brake so as to be movable in the left and right directions, and a workpiece in a horizontal position on the upper side, and a pair of left and right carriages (movable frames) provided on each carriage so as to be movable up and down. (sheet metal); and a pair of first work clamps that are provided on each elevator body to protrude inward in the left-right direction and grip the ends of the workpieces in a vertical position. The lifting body of at least one of the lifting bodies is provided with an escape recess that protrudes outward in the left-right direction to avoid interference with a bending flange formed at the end of the workpiece, and is in a vertical position. a second work clamp for gripping an end of the work.

In the first embodiment, each first work clamp includes a first fixed clamp claw provided on each elevating body so as to protrude inward in the left-right direction, and a first fixed clamp claw provided on each elevating body so as to move toward and away from the first fixed clamp claw. and a first movable clamp claw provided movably in the direction. The second work clamp includes a second fixed clamp claw provided on one of the elevating bodies so as to protrude outward in the left-right direction, and a second fixed clamp claw provided on one of the elevating bodies so as to move toward and away from the second fixed clamp claw. and a second movable clamp claw provided movably in the direction. In this case, the second movable clamp claw is configured integrally with the corresponding first fixed clamp claw, and the relief recess is formed in the second fixed clamp claw or the second movable clamp claw.

According to the first embodiment, as described above, the second work clamp has the relief recess. Therefore, during a series of bending operations on a small workpiece, the bending flange-formed end of the workpiece can be gripped by the second workpiece clamp while avoiding interference between the bending flange and the second workpiece clamp. .

A bending system according to a second embodiment includes a press brake that bends a workpiece, a bending robot that assists in bending a workpiece, a regripping device according to the first embodiment, and a robot hand of the bending robot. Before re-gripping a small workpiece, in order to secure (form) an operating area for the bending robot in front of the press brake (on the front side) and outside in the left-right direction of one of the carriages, and a regripping controller that controls the gripping device so that the carriage moves inward in the left-right direction.

According to the second embodiment, the same effect as that of the first embodiment is achieved.

According to the present invention, during a series of bending operations on a small workpiece, the robot hand of the bending robot is re-grabbed between the end portion of the small workpiece where the bending flange has not been formed and the end portion where the bending flange has been formed. be able to. That is, according to the present invention, the bending system can perform a series of bending operations on a small workpiece to the end.

FIG. 1 is a schematic plan view of a bending system according to this embodiment. FIG. 2 is a schematic front view of the regripping device according to this embodiment. FIG. 3 is a front view of the upper part of the regripping device according to this embodiment. FIG. 4 is a plan view of the upper part of the regripping device according to this embodiment. FIG. 5(a) is a diagram showing a small workpiece in which bending flanges are formed at three ends. FIG. 5(b) is a perspective view of a small workpiece with bending flanges formed at three ends. FIG. 6 is a control block diagram of the bending system according to this embodiment. FIG. 7A shows a state in which the movable gripper claw and the fixed gripper claw grip the end of the small workpiece that has not been bent and flanged, and the second work clamp grips the end of the small workpiece that has been bent and flanged. FIG. FIG. 7B shows how the movable gripper claw and the fixed gripper claw grip the end of the small workpiece that has not been bent and flanged, and the second work clamp grips the end of the small workpiece that has been bent and flanged. FIG. FIG. 8A shows a state in which the bending and flanging end of the small workpiece is gripped by the second work clamp, and the other bending and flanging end of the small workpiece is being gripped by the movable gripper claw and the fixed gripper claw. FIG. 3 is a front view showing the situation. FIG. 8B shows a state in which the second work clamp grips the bent and flanged end of the small workpiece, and the movable gripper claw and fixed gripper claw grip the other bent and flanged end of the small workpiece. FIG. 3 is an enlarged plan view showing the situation.

This embodiment will be described below with reference to FIGS. 1 to 8B.

Note that in the specification and claims of the present application, the term "provided" includes not only direct provision but also indirect provision via another member. The "left-right direction" is one of the horizontal directions, and is synonymous with the length direction of the press brake. The term "inner side in the left-right direction" refers to the side toward the longitudinal center (center line) of the press brake in the left-right direction. The term "outer side in the left-right direction" refers to the side opposite to the side toward the center in the length direction of the press brake in the left-right direction. The "front-back direction" is a horizontal direction perpendicular to the left-right direction, and has the same meaning as the depth direction of the press brake. In the drawings, "FF" indicates the front direction, "FR" indicates the rear direction, "L" indicates the left direction, "R" indicates the right direction, "U" indicates the upward direction, and "D" indicates the downward direction.

As shown in FIGS. 1 and 2, a bending system 10 according to the present embodiment is a system for bending a workpiece (sheet metal) W. As shown in FIGS. The workpieces W to be processed by the bending system 10 include a normal-sized or large-sized workpiece WA, a strip-shaped workpiece WB, and a small workpiece WC. The bending system 10 also includes a press brake 12 that bends the workpiece W by cooperation of a punch mold (not shown) and a die mold (not shown). Note that the configuration of the press brake 12 is well known, and its explanation will be omitted.

The bending system 10 includes a bending robot 14 that assists in bending the workpiece W, and the bending robot 14 is mounted on a support frame 16 installed in front of the press brake 12 so as to be movable in the left-right direction. . The bending robot 14 also includes a multi-joint robot arm 18 and a gripping robot hand 20 that is detachably attached to the tip of the robot arm 18 and holds the workpiece W. The overall configuration of the bending robot 14 including the robot hand 20 is a known configuration shown in Patent Document 2.

The robot hand 20 includes a hand main body 22 (see FIG. 7B) that is removably attached to the tip of the robot arm 18, and a fixed gripper claw (fixed clamp claw) 24 (see FIG. 7B) that is provided on the hand main body 22. have. The robot hand 20 also has a movable gripper claw (movable clamp claw) 26 (see FIG. 7B) provided on the hand body 22 so as to be movable toward and away from the fixed gripper claw 24. The movable gripper claw 26 is formed with an escape recess 26d (see FIG. 7B) to avoid interference with a bending flange WCf (see FIG. 5) formed at the end of the small workpiece WC.

Although not shown in the drawings, in this embodiment, when bending a normal-sized or large-sized workpiece WA, a suction-type robot hand shown in Patent Document 1 is used as a robot arm instead of the robot hand 20. It is attached to the tip of 18. When bending a strip-shaped workpiece WB, in addition to using the robot hand 20, a grasping type robot hand disclosed in Patent Document 1 is attached to the tip of the robot arm 18.

The bending system 10 includes a re-gripping device 28 for re-gripping (re-holding) the workpiece W by the robot hand 20 or the like. The specific configuration of the regripping device 28 according to this embodiment is as follows.

As shown in FIGS. 1 to 4, a pair of left and right guide frames 30 are disposed between the press brake 12 and the support frame 16, and each guide frame 30 extends in the left and right direction. Further, each guide frame 30 is provided with a carriage 32 that extends in the vertical direction and is movable in the left-right direction. In other words, a pair of left and right carriages 32 are provided in front (on the front side) of the press brake 12 so as to be movable in the left and right direction via a pair of left and right guide frames 30 . A servo motor 34 as a movement actuator for moving each carriage 32 in the left-right direction is provided at the outer end of each guide frame 30 in the left-right direction.

Each carriage 32 is provided with an elevating body 36 that extends in the vertical direction and is movable up and down (movable in the up and down direction). Each elevating body 36 moves up and down between a raised position (height position shown in FIG. 2) and a lowered position. Each elevating body 36 rises from the lowered position to the raised position when the workpiece W is regrasped by the robot hand 20 or the like. Further, on the back surface (rear side surface) of each carriage 32, an elevating cylinder 38 (see FIGS. 7B and 8B) is provided as an elevating actuator for elevating each elevating body 36. Each elevating cylinder 38 has an actuating rod 38r (see FIGS. 7B and 8B) that can be raised and lowered, and the tip of each actuating rod 38r is connected to an appropriate position of each elevating body 36.

As shown in FIGS. 3 and 4, each elevating body 36 has a flat workpiece placement section 40 on its upper side on which a normal-sized or large-sized workpiece WA in a horizontal position is placed. As shown in Patent Document 1, the pair of workpiece placement units 40 are used when a suction-type robot hand changes grip between the front and back surfaces of a normal-sized workpiece or a large-sized workpiece WA.

A first work clamp 42 is provided at the upper part of the front surface (front side surface) of each elevating body 36 and protrudes inward in the left-right direction for gripping an end portion of a vertically-positioned strip-shaped work WA. As shown in Patent Document 1, the pair of first work clamps 42 are used when a gripping type robot hand changes grip between one end of a strip-shaped work WA and the other end.

Each first work clamp 42 includes a clamp cylinder 44 provided at the upper part of the front of each elevating body 36. Each clamp cylinder 44 has a cylinder main body 44a fixed to the front of each elevating body 36, and an actuation rod 44r provided on each cylinder main body 44a so as to be movable in the front-rear direction. Further, each first work clamp 42 has a first fixed clamp claw 46 provided at the upper part of the front of each elevating body 36 so as to protrude inward in the left-right direction through the cylinder body 44a of each clamp cylinder 44. . Each first fixed clamp claw 46 includes a grip pad 46p made of an elastic material such as rubber at its tip.

Each first work clamp 42 has a first movable clamp claw 50 provided on the front of each elevating body 36 so as to be movable in the front-rear direction toward and away from the first fixed clamp claw 46 via a guide rod 48. are doing. Each first movable clamp claw 50 includes a grip pad 50p made of an elastic material such as rubber at its tip. The base end of each first movable clamp claw 50 is connected to the tip of the actuating rod 44r of each clamp cylinder 44. In other words, each clamp cylinder 44 corresponds to a clamp actuator that moves each first movable clamp claw 50 in the front-back direction.

A second work clamp 52 that grips the end of a small workpiece WC in a vertical position is provided at the upper part of the front of the right-hand elevator 36 of the pair of elevators 36, protruding outward in the left-right direction (Fig. 7B and FIG. 8B). The second work clamp 52 is used to re-grip the robot hand 20 between the end of the small workpiece WC that has not been bent and flanged and the end that has been bent and flanged. Here, as shown in FIGS. 5(a) and 5(b), the end where the bending flange is not formed is the end where the bending flange WCf is planned to be formed among the plurality of ends of the small workpiece WC. This is called. The bending flange-formed end refers to the end after the bending flange WCf has been formed, among the plurality of ends of the small workpiece WC. In addition, in FIG. 5(b), the state in which the bending flange WCf is formed on the end portion of the workpiece WC where the bending flange is not formed is shown by a two-dot chain line.

As shown in FIGS. 3 and 4, the second work clamp 52 is a second fixed clamp that is provided at the upper part of the front of the right-side elevating body 36 and protrudes outward in the left-right direction via the cylinder body 44a of the clamp cylinder 44. It has a claw 54. Each second fixed clamp claw 54 includes two gripping pads 54p made of an elastic material such as rubber at its tip. The second work clamp 52 has a second movable clamp claw 58 which is provided on the upper part of the front surface of the right side elevating body 36 so as to be movable in the front and rear directions toward and away from the second fixed clamp claw 54 via a guide rod 56. have. The second movable clamp claw 58 includes two gripping pads 58p made of an elastic material such as rubber at its tip. The second movable clamp claw 58 is configured integrally with the corresponding first movable clamp claw 50 on the right side, and moves in the front-back direction integrally with the first movable clamp claw 50 on the right side by driving the right clamp cylinder 44. do.

The second fixed clamp claw 54 is formed with an escape recess 54d recessed in the rear direction to avoid interference with a bending flange WCf formed at the end of the small workpiece WC. In other words, the second work clamp 52 has the escape recess 54d. The recess amount of the escape recess 54d of the second fixed clamp claw 54 is set to be larger than the height of the bending flange WCf. Note that instead of forming the escape recess 54d in the second fixed clamp claw 54, the second movable clamp claw 58 has an escape recess (not shown) in the forward direction to avoid interference with the bending flange WCf of the small workpiece WC. It may be formed with a recess.

As shown in FIG. 6, the bending system 10 includes an NC device 60 that controls the press brake 12 based on a bending program and the like, and the NC device 60 is configured by a computer. The bending system 10 includes a robot controller 62 that controls the bending robot 14 based on a bending program and the like. The robot controller 62 is configured by a computer, and the robot controller 62 is connected to the NC device 60.

The bending system 10 includes a regrip controller 64 that controls the regrip device 28 (a pair of servo motors 34, a pair of lifting cylinders 38, and a clamp cylinder 44) based on a bending program and the like. The regripping controller 64 is configured by a computer and is connected to the NC device 60. Furthermore, before the robot hand 20 regrips the small workpiece WC, the regripping controller 64 moves the bending robot 14 to the operating area MR (Fig. 7A and FIG. 8A), the right servo motor 34 is controlled so that the right carriage 32 moves inward in the left-right direction. Note that if the configuration is such that the horizontal positions of the first work clamp 42 and the second work clamp 52 with respect to the right lifting body 36 can be reversed, it is not necessary to control the right servo motor 34 as described above. , the operating range MR of the bending robot 14 can be secured.

Next, the effects of this embodiment will be explained with reference to FIGS. 1, 5, 6, 7A to 8B, etc.

As shown in FIGS. 1 and 6, the bending robot 14 is controlled by the robot controller 62, and the press brake 12 is controlled by the NC device 60, thereby bending the three ends of the small workpiece WC. conduct. Thereby, as shown in FIGS. 5(a) and 5(b), bending flanges WCf can be formed at the three ends of the small workpiece WC.

Thereafter, as shown in FIGS. 6, 7A, and 7B, the right servo motor 34 is controlled by the regripping controller 64 to move the right carriage 32 inward in the left-right direction so that it is in front of the press brake 12. The operation area MR of the bending robot 14 is secured outside the right carriage 32 in the left-right direction. Next, with the movable gripper claw 26 and the fixed gripper claw 24 gripping the end portion of the small workpiece WC that has not been bent into a flange, the bending robot 14 is controlled by the robot controller 62 in the operation area MR of the bending robot 14. The robot arm 18 and the like are operated appropriately. Then, the end portion of the small workpiece WC that has been bent and flan-formed is located between the second fixed clamp claw 54 and the second movable clamp claw 58. Then, the clamp cylinder 44 is controlled by the gripping controller 64, and the second workpiece clamp 52 (second fixed clamp claw 54 and second movable clamp claw 58) grips the bent end of the small workpiece WC. .

As shown in FIGS. 6, 8A, and 8B, after the second work clamp 52 grips the bending and flanged end of the small workpiece WC, the robot controller 62 controls the bending robot 14 to hold the movable gripper claws. 26 and the fixed gripper claws 24 are released. Further, the bending robot 14 is controlled by the robot controller 62 to appropriately operate the robot arm 18 and the like in the operation area MR of the bending robot 14, while the movable gripper claw 26 and the fixed gripper claw 24 are used to form other bending flanges on the workpiece WC. Grasp the end of the Then, the clamp cylinder 44 is controlled by the regripping controller 64 to release the gripping state by the second workpiece clamp 52. Thereby, the robot hand 20 can be re-grasped between the end portion of the small workpiece WC where the bending flange has not been formed and the end portion where the bending flange has been formed.

After regripping the robot hand 20, the bending robot 14 is controlled by the robot controller 62, and the press brake 12 is controlled by the NC device 60. Bending process is performed on the edge of the As a result, bending flanges WCf are formed at the four ends of the small workpiece WC, and a series of bending operations on the small workpiece WC are completed.

As described above, the second fixed clamp claw 54 is provided with an escape recess 54d recessed in the rearward direction to avoid interference with the bending flange WCf. Therefore, during a series of bending processes of the small workpiece WC, the bending flange-formed end of the small workpiece WC is held by the second workpiece clamp 52 while avoiding interference between the bending flange WCf and the second workpiece clamp 52. can be grasped. Therefore, according to the present embodiment, during a series of bending processes of the small workpiece WC, as described above, between the end of the small workpiece WC where the bending flange has not been formed and the bending and flanged end thereof. The grip of the robot hand 20 can be changed. That is, according to the present embodiment, as described above, the bending system 10 can perform a series of bending processes (four-sided bending) on the small workpiece WC to the end.

Further, as described above, the second movable clamp claw 58 is configured integrally with the corresponding first movable clamp claw 50 on the right side. Therefore, the first movable clamp claw 50 and the second movable clamp claw 58 on the right side can be moved in the front-rear direction by the right clamp cylinder 44, which is one clamp actuator. As a result, according to the present embodiment, it is possible to suppress an increase in the number of actuators of the regripping device 28 and to simplify the configuration of the regripping device 28.

Furthermore, as described above, before the robot hand 20 regrips the small workpiece WC, the regripping controller 64 moves the bending robot 14 outward in the left-right direction of the carriage 32 on the right side in front of the press brake 12. In order to secure the operating range MR, the right servo motor 34 is controlled so that the right carriage 32 moves inward in the left-right direction. Therefore, according to the present embodiment, the small workpiece WC can be re-grabbed by the robot hand 20 in the vicinity of the press brake 12, and the workability of a series of bending operations on the workpiece WC can be improved.

Note that the present invention is not limited to the description of the embodiments described above, and can be implemented in various forms by making appropriate changes. The scope of rights encompassed by the present invention is not limited to the description of the embodiments described above.

10 Bending System 12 Press Brake 12c Press Brake Center 14 Bending Robot 16 Support Frame 18 Robot Arm 20 Robot Hand 22 Hand Body 24 Fixed Gripper Claw 26 Movable Gripper Claw 26d Relief Recess 28 Grasping Replacement Device 30 Guide Frame 32 Carriage 34 Servo Motor (moving actuator)
36 Lifting body 38 Lifting cylinder (lifting actuator)
38r Operating rod 40 Work placement part 42 First work clamp 44 Clamp cylinder (clamp actuator)
44a Cylinder body 44r Operating rod 46 First fixed clamp claw 46p Gripping pad 48 Guide rod 50 First movable clamp claw 50p Gripping pad 52 Second work clamp 54 Second fixed clamp claw 54p Gripping pad 52d Relief recess 56 Guide rod 58 Second Movable clamp claw 58p Gripping pad 60 NC device 62 Robot controller 64 Grasping change controller MR Bending robot operating area W Work (sheet metal)
WA Normal size or large workpiece WB Band-shaped workpiece WC Small workpiece WCf Bending flange

Claims (3)

A pair of left and right carriages that are movable in the left and right directions in front of the press brake,
an elevating body provided on each carriage so as to be movable up and down, and having a work placement part on the upper side for placing a work in a horizontal position;
a first work clamp that is provided on each elevating body to protrude inward in the left-right direction and grips an end of a workpiece in a vertical position;
The lifting body of at least one of the pair of lifting bodies is provided with a relief recess that protrudes outward in the left-right direction to avoid interference with a bending flange formed at the end of the workpiece, and the vertical A grip change device comprising: a second work clamp that grips an end of a work in a posture. Each first work clamp is
a first fixed clamp claw provided on each elevating body so as to protrude inward in the left-right direction;
a first movable clamp claw provided on each elevating body so as to be movable in the front-rear direction toward and away from the first fixed clamp claw;
The second work clamp is
a second fixed clamp claw provided on one of the elevating bodies so as to protrude outward in the left-right direction;
a second movable clamp claw provided on one of the elevating bodies so as to be movable in the front-rear direction toward and away from the second fixed clamp claw;
The second movable clamp claw is configured integrally with the corresponding first movable clamp claw, and the escape recess is formed in the second fixed clamp claw or the second movable clamp claw. Item 1. The regripping device according to item 1. A press brake that bends the workpiece,
A bending robot that assists in bending workpieces,
The grasp re-gripping device according to claim 1 or claim 2;
Before regripping a workpiece with the robot hand of the bending robot, in order to secure an operating area of the bending robot in front of the press brake and outside of any of the carriages in the left-right direction, A bending system comprising: a regripping controller that controls the gripping device so that the carriage moves inward in the left-right direction.

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