Workpiece loading / unloading device and method for controlling workpiece loading / unloading device

Abstract

In a workpiece carrying-in and carrying-out device, the operation area of a robot on the tray side becomes narrow. The workpiece carrying-in and carrying-out device (100) is provided with an arrangement part (301), a tray moving part (302), an arm part (120), a hand part (120) and a control part (130), wherein the arrangement part (301) is provided with two trays (310) for accommodating workpieces (10); the tray moving part (302) enables the trays (310) to move; the arm part (120) moves between the workpiece carrying-in and carrying-out device and an automatic lathe (200) for processing the workpieces (10); the control unit (130) controls the arm unit (110) to move within a range formed by combining a first range (S1) in which the hand unit (120) can reach the entire area of the first tray (310) and a second range (S2) in which the hand unit (120) can only reach a part of the second tray (310), and controls the tray moving unit (302) so as to move the first tray (310) out while the arm unit (120) is separated from the second tray (310), and controls the tray moving unit (302) so as to move the second tray (310) out while the arm unit (120) is separated from the second tray (310). The second tray (310) is moved to the first position (P1).

Description

Technical Field

[0001] The present invention relates to a workpiece loading and unloading device and a control method for the workpiece loading and unloading device. Background Art

[0002] There is known a workpiece loading and unloading device that transfers a workpiece between a pallet on which a plurality of workpieces are arranged and accommodated and a machine tool, either from the pallet into the machine tool or from the machine tool out to the pallet. As such a workpiece loading and unloading device, there is a device that uses a robot having a hand at the front end of an arm. The robot grasps one workpiece before machining accommodated in the pallet with the hand, and the arm rotates, thereby transferring the grasped workpiece to the machine tool. Further, the robot receives and grasps one workpiece after machining by the machine tool, and returns the grasped workpiece to the original position (the same position) where it was accommodated before machining in the pallet (for example, refer to Patent Document 1).

[0003] In addition, there is also known a device in which a robot moves a workpiece between a pallet on which workpieces before machining are arranged and a pallet on which workpieces after machining are arranged (for example, refer to Patent Document 2).

[0004] Prior Art Documents Patent Documents Patent Document 1: Japanese Patent No. 3362656 Patent Document 2: Japanese Unexamined Patent Application Publication No. 2006-043866 Summary of the Invention Problems to be Solved by the Invention Among them, the robot has a first hand that grasps a workpiece before machining from the pallet and transfers it to the machine tool, and a second hand that receives and grasps a workpiece after machining from the machine tool and returns it to the pallet.

[0005] In addition, two pallets are arranged and configured on the pallet side. The structure with two pallets has the following advantages. That is, for a structure with only one pallet, in order to return the workpiece after machining to the original position of the pallet, it is necessary to replace the pallet on which the workpiece after machining is accommodated with the pallet on which the workpiece before machining is accommodated after accommodating the workpiece after machining in the pallet.

[0006] In contrast, in the structure with two pallets, the first pallet can be replaced during the transfer of the workpiece between the second pallet. Therefore, it is not necessary to stop the operation of the robot for pallet replacement, and the operation efficiency of the robot can be improved.

[0007] However, the robot needs to reach all the workpieces accommodated in the two configured pallets respectively, and it is necessary to set a large reach range of the robot at the pallet side. Moreover, in order to expand the reach range of the robot on the pallet side, it is necessary to increase the length of the arm. In addition, in order to improve the rigidity of the part that supports the lengthened arm, the weight of the robot increases, the robot becomes larger, and thus the cost increases.

[0008] The present invention has been completed in view of the above circumstances, and its object is to provide a workpiece loading and unloading device and a control method for the workpiece loading and unloading device that can set a narrow operation area on the pallet side of the robot and prevent the cost of the robot from increasing.

[0009] Means for solving the problem A first aspect of the present invention is a workpiece loading and unloading device, comprising: a configuration unit configured with two pallets on which a plurality of workpieces are arranged and accommodated; a pallet moving unit for moving the pallets arranged in the configuration unit; an arm unit for moving between the workpiece loading and unloading device and a machine tool for processing the workpieces; a hand unit for gripping the workpieces and transferring the workpieces between the pallets and the machine tool; and a control unit for controlling the pallet moving unit, the arm unit, and the hand unit; in a top-down perspective, the configuration unit arranges and configures two pallets, namely a first pallet arranged at a first position and a second pallet arranged at a second position adjacent to the first position, and the control unit controls the arm unit to move within a range combined by a first range and a second range, the first range being a range where the hand unit can reach all the workpieces arranged on the first pallet, and the second range being a range where the hand unit can only reach a part of the workpieces arranged on the second pallet and arranged at a position close to the first pallet. When the first pallet accommodates all the workpieces that can be arranged and accommodated, and the hand unit grips the workpieces arranged at the position close to the first pallet on the second pallet, during the period when the arm unit is separated from the pallet, the control unit controls the pallet moving unit to move the second pallet towards the first position.

[0010] A second aspect of the present invention is a control method for a workpiece loading and unloading device, which controls the workpiece loading and unloading device. The workpiece loading and unloading device has: a configuration unit configured with two pallets, in which a plurality of workpieces are arranged and accommodated; a pallet moving unit that moves the pallets arranged in the configuration unit; an arm unit that moves between the workpiece loading and unloading device and a machine tool for processing the workpiece; and a hand unit that holds the workpiece and transfers the workpiece between the pallet and the machine tool. In a top-down view, the configuration unit arranges and configures two pallets, namely a first pallet arranged at a first position and a second pallet arranged at a second position adjacent to the first position. The arm unit is controlled to move within a range composed of a first range and a second range. The first range is the range where the hand unit can reach all the workpieces arranged on the first pallet, and the second range is the range where the hand unit can only reach a part of the workpieces arranged on the second pallet and located at positions close to the first pallet. When the first pallet contains all the workpieces that can be arranged and accommodated, and the hand unit holds the workpieces arranged at positions close to the first pallet on the second pallet, during the period when the arm unit is separated from the pallet, the pallet moving unit is controlled to move the second pallet towards the first position.

[0011] Advantages of the Invention According to the workpiece loading and unloading device and the control method for the workpiece loading and unloading device of the present invention, an increase in the cost of the robot can be prevented. Description of the Drawings

[0012] Figure 1 is a top view of an embodiment of the workpiece loading and unloading device of the present invention observed from above in the vertical direction.

[0013] Figure 2 is Figure 1 a front view from the perspective of arrow A in

[0014] Figure 3 is Figure 2 a side view from the perspective of arrow B in

[0015] Figure 4A is a perspective view showing the appearance of the stocker.

[0016] Figure 4B is a view of the stocker observed from the left side.

[0017] Figure 5 is a top view showing the positional relationship between the first position where the first pallet is arranged, the second position where the second pallet is arranged, and the axis C of the arm unit of the robot in the configuration unit.

[0018] Figure 6It is a top view (one) showing the operation of the workpiece loading and unloading device and corresponding to Figure 5 ...

[0019] Figure 7 It is a top view (two) showing the operation of the workpiece loading and unloading device and corresponding to Figure 5 ...

[0020] Figure 8 It is a top view (three) showing the operation of the workpiece loading and unloading device and corresponding to Figure 5 ...

[0021] Figure 9 It is a top view (four) showing the operation of the workpiece loading and unloading device and corresponding to Figure 5 ...

[0022] Figure 10 It is a top view corresponding to the state where the arrangement of the stocker is offset when there is an obstacle within the range where the stocker is to be arranged, showing Figure 5 ... DETAILED DESCRIPTION

[0023] Embodiments of the workpiece loading and unloading device and the control method of the workpiece loading and unloading device of the present invention are described below with reference to the drawings.

[0024] <Structure> Figure 1 It is a top view showing an embodiment of the workpiece loading and unloading device of the present invention as viewed from above in the vertical direction, Figure 2 is Figure 1 a front view from the perspective of arrow A in Figure 3 is Figure 2 a left side view from the perspective of arrow B in

[0025] (Automatic Lathe) The automatic lathe 200 is an example of a machine tool in the workpiece loading and unloading device of the present invention. The automatic lathe 200 is an NC (Numerical Control) lathe whose operation is controlled by a computer that reads a specified program and operates. As Figures 1 - 3 shown, in the automatic lathe 200 of the embodiment, a front spindle 210 and a rear spindle 220 are provided inside the main body housing 230, and an operation panel 240 is provided outside the main body housing 230. The operation panel 240 has a display screen 251, a keyboard 252, and a control unit that controls the operations of tools (not shown).

[0026] The front main spindle 210 can rotate around the Z-axis. The back main spindle 220 can rotate around the Z-axis and linearly move along the Z-axis. The front main spindle 210 and the back main spindle 220 are coaxially arranged.

[0027] The automatic lathe 200 controls the clamping (Chuck) and release (Release) of the workpiece 10 described later, the rotation of the front main spindle 210 around the Z-axis in the state where the workpiece 10 is held by the front main spindle 210, the movement of the tool, the transfer of the workpiece 10 to the back main spindle 220, the rotation of the back main spindle 220 around the Z-axis and the movement along the Z-axis in the state where the workpiece 10 is held by the back main spindle 220, the movement of the tool, etc. through the control unit of the operation panel 240, and thereby performs the transfer and machining of the workpiece 10.

[0028] (Stock feeder) Figure 4A is a perspective view showing the appearance of the stock feeder 300, Figure 4B is a view of the stock feeder 300 observed from the left side. As Figure 1 、 2 shown, the stock feeder 300 is arranged close to the automatic lathe 200 on the left side of the automatic lathe 200. The stock feeder 300 houses a plurality of trays 311 and a plurality of trays 312. A plurality of workpieces 11 before being processed by the automatic lathe 200 are arranged on the tray 311, and a plurality of workpieces 12 after being processed by the automatic lathe 200 are arranged on the tray 312.

[0029] In addition, in the following description, when not distinguishing between the workpiece 11 before processing and the workpiece 12 after processing, it is only referred to as the workpiece 10. Also, regarding the tray 311 that houses the workpiece 11 before processing and the tray 312 that houses the workpiece 12 after processing, there is no physical difference as the tray 310. The difference is only whether the workpiece 10 housed is the workpiece 11 before processing or the workpiece 12 after processing. Therefore, when not distinguishing between the tray 311 and the tray 312, it is only referred to as the tray 310.

[0030] One tray 310 houses, for example, 30 workpieces 10. As Figure 1 shown, in a top-down perspective, 30 workpieces 10 are respectively arranged and housed at preset specified positions, for example, 5 in the longitudinal direction × 6 in the transverse direction, on the tray 310.

[0031] As Figure 4A 、 Figure 4B shown, a configuration part 301 is provided at the topmost layer of the stock feeder 300. In a top-down perspective, two trays 310 are arranged and configured along the width direction N in the configuration part 301. The positions where the two trays 310 are respectively arranged are called the first position P1 and the second position P2, and the first position P1 and the second position P2 are adjacent positions.

[0032] In the storage device 300, below the first position P1, there are a storage space 321 and a storage space 322. The storage space 321 can store a plurality of trays 312 containing the processed workpieces 12 in a stacked state along the height direction H, and the storage space 321 can store a plurality of trays 311 containing the workpieces 11 before processing in a stacked state along the height direction H.

[0033] In addition, the storage device 300 is formed with openings 331, 332. The openings 331, 332 can take out a plurality of trays 311 stacked below the first position P1 to the outside of the storage device 300 or put them into the storage device 300 from the outside of the storage device 300 while maintaining the stacked state along the access direction M.

[0034] In addition, as Figure 4B shown, the storage device 300 has a tray moving unit 302 and a storage device control unit 340. The storage device control unit 340 controls the operation of the tray moving unit 302. As described later, the storage device control unit 340 controls the tray moving unit 302 according to the instructions of the control unit 130 of the robot 100. In addition, the storage device control unit 340 can also be independent of the control unit 130 of the robot 100, not accept the control of the control unit 130, and control the tray moving unit 302 by the storage device 300 alone.

[0035] The tray moving unit 302 has two mounting tables 302a, a lift 302b, a lateral guide rail 302c, a handling and holding unit 302d, and a placement and holding unit 302e. One mounting table 302a is provided in the storage space 321 below the first position P1, and the other mounting table 302a is provided in the storage space 322 below the second position P2.

[0036] The handling and holding unit 302d is connected to the lift 302b described later. The handling and holding unit 302d has two clamping members 302d1, 302d2. The two clamping members 302d1, 302d2 are set to have the same position in the height direction all the time. The two clamping members 302d1, 302d2 are arranged at two outer sides in the width direction N with respect to the tray 310 at positions separated from the tray 310.

[0037] The handling and holding unit 302d operates in a manner of switching between a non-holding state and a holding state. In the non-holding state, the clamping members 302d1, 302d2 are separated from the tray 310. In the holding state, the clamping members 302d1, 302d2 move toward the center side in the width direction N, and the clamping members 302d1, 302d2 clamp and hold the tray 310 from the outer sides in the width direction N.

[0038] The elevator 302b can move the handling and holding part 302d up and down in the height direction H. The elevator 302b can move horizontally along the horizontal guide rail 302c.

[0039] The placement and holding parts 302e are respectively arranged at the first position P1 and the second position P2 of the placement part 301. Each placement and holding part 302e has two clamping members 302e1, 302e2. The two clamping members 302e1, 302e2 are arranged at positions separated from the tray 310 on two outer sides in the access direction M (refer to Figure 4A ).

[0040] The placement and holding part 302e operates in a manner of switching between a non-holding state and a holding state. In the non-holding state, the clamping members 302e1, 302e2 are separated from the tray 310. In the holding state, the clamping members 302e1, 302e2 move toward the center side in the access direction M, and the clamping members 302e1, 302e2 clamp and hold the tray 310 from the outer sides in the access direction M. In addition, the placement and holding part 302e arranged at the first position P1 and the placement and holding part 302e arranged at the second position P2 are independent of each other and switch the above non-holding state and holding state.

[0041] The tray moving part 302 moves the tray 310 in the following manner through the above structure. First, the handling and holding part 302d moves to the height position of the uppermost tray 310 among the trays 310 stacked on the mounting table 302a in the storage space 322 below the second position P2 through the elevator 302b. Then, at this position, the clamping members 302d1, 302d2 clamp the uppermost tray 310 from the outer sides in the width direction N and hold the uppermost tray 310.

[0042] Next, the handling and holding part 302d is lifted upward by the elevator 302b, and the uppermost tray 310 rises to the horizontal movement space 323 formed directly below the placement part 301. The elevator 302b moves horizontally along the horizontal guide rail 302c, and thus the tray 310 rising to directly below the second position P2 in the horizontal movement space 323 moves within the horizontal movement space 323 from directly below the second position P2 to directly below the first position P1.

[0043] Next, the elevator 302b rises to the first position P1 of the placement part 301 and places the tray 310 held by the handling and holding part 302d at the first position P1. Among them, the clamping members 302e1, 302e2 of the placement and holding part 302e arranged at the first position P1 clamp the tray 310 arranged at the first position P1 from the outer sides in the access direction M and hold the tray 310 arranged at the first position P1.

[0044] After the tray 310 disposed at the first position P1 is held by the configuration holding part 302e, the clamping members 302d1 and 302d2 of the transfer holding part 302d move in a non-holding state and separate from the tray 310. Then, the elevator 302b lowers the transfer holding part 302d to the horizontal movement space 323 directly below the first position P1, and the elevator 302b moves horizontally along the lateral guide rail 302c and moves to directly below the second position P2 in the horizontal movement space 323. After that, the transfer holding part 302d descends to the storage space 322 below the second position P2 and moves to the height position of the uppermost tray 310 among the trays 310 stacked on the mounting table 302a in the storage space 322 below the second position P2 at that time point.

[0045] The clamping members 302d1 and 302d2 of the transfer holding part 302d clamp the uppermost tray 310 from the outside in the width direction N and hold the uppermost tray 310. The elevator 302b lifts the transfer holding part 302d upward to move the tray 310 to the second position P2 of the configuration part 301, and disposes the tray 310 clamped by the transfer holding part 302d at the second position P2. Among them, the clamping members 302e1 and 302e2 of the configuration holding part 302e provided at the second position P2 clamp the tray 310 disposed at the second position P2 from the outside in the access direction M and hold the tray 310 disposed at the second position P2.

[0046] After the tray 310 disposed at the second position P2 is held by the configuration holding part 302e, the clamping members 302d1 and 302d2 of the transfer holding part 302d move in a non-holding state and separate from the tray 310. Then, the elevator 302b lowers the transfer holding part 302d to the storage space 322 below the second position P2 and stops. Through the above operations, the tray moving part 302 places the trays 310 on which the workpieces 10 before processing are arranged at the first position P1 and the second position P2 respectively.

[0047] Next, the operation of moving and replacing the tray 310 disposed in the configuration part 301 will be described. Through the above operations of the transfer holding part 302d and the elevator 302b, the transfer holding part 302d moves to the first position P1, and the clamping members 302d1 and 302d2 of the transfer holding part 302d clamp the first tray 310 disposed at the first position P1 and on which the processed workpieces 10 are arranged to become a holding state. The clamping members 302e1 and 302e2 of the configuration holding part 302e holding the first tray 310 become a non-holding state.

[0048] Next, the elevator 302b lowers the transfer holding unit 302d to the storage space 321 below the first position P1, and places the first tray 310 held by the transfer holding unit 302d on the placement table 302a arranged below the first position P1. Then, the transfer holding unit 302d becomes a non-holding state, and the transfer holding unit 302d separates from the first tray 310.

[0049] Next, when the elevator 302b raises the transfer holding unit 302d to the horizontal movement space 323 directly below the first position P1, the elevator 302b moves horizontally along the lateral guide rail 302c, moves to directly below the second position P2 in the horizontal movement space 323, and then raises the transfer holding unit 302d to the second position P2. Then, the clamping members 302d1, 302d2 of the transfer holding unit 302d clamp and hold the second tray 310 held by the configuration holding unit 302e at the second position P2. After that, the configuration holding unit 302e becomes a non-holding state and separates from the second tray 310.

[0050] Next, the elevator 302b lowers the transfer holding unit 302d to the horizontal movement space 323 directly below the second position P2, the elevator 302b moves horizontally along the lateral guide rail 302c, moves to directly below the first position P1 in the horizontal movement space 323, and then raises the transfer holding unit 302d to the first position P1. Thus, the second tray 310 moves from the second position P2 to the first position P1. The second tray 310 is held by the configuration holding unit 302e at the first position P1, and the transfer holding unit 302d becomes a non-holding state in which it does not hold the second tray 310 and separates from the second tray 310.

[0051] Next, the elevator 302b lowers the transfer holding unit 302d to the horizontal movement space 323 directly below the first position P1, the elevator 302b moves horizontally along the lateral guide rail 302c, moves to directly below the second position P2 in the horizontal movement space 323, and then the transfer holding unit 302d descends to the storage space 322 below the second position P2, and holds the uppermost tray 310 among the trays 310 stacked on the placement table 302a in the storage space 322 below the second position P2 at this time point.

[0052] The elevator 302b lifts the transfer holding unit 302d upward, moves the tray 310 to the second position P2 of the configuration unit 301, and places the tray 310 clamped by the transfer holding unit 302d at the second position P2. The tray 310 arranged at the second position P2 is held by the configuration holding unit 302e.

[0053] Thereafter, the transfer and holding unit 302d moves in a non-holding state and separates from the tray 310, and the elevator 302b lowers the transfer and holding unit 302d to the storage space 322 below the second position P2 and stops. Through the above operations, the tray 310 disposed in the placement unit 301 can be replaced.

[0054] The first position P1 and the second position P2 of the placement unit 301 are positions where the workpiece 10 is transferred between the robot 100 and the automatic lathe 200 described later. Specifically, the robot 100 holds and transfers a pre-processed workpiece 11 accommodated in the tray 311 at the first position P1 to the automatic lathe 200, and the robot 100 receives and holds the processed workpiece 12 from the automatic lathe 200, and the processed workpiece 12 returns to the specified position of the tray 311 where it was located before processing.

[0055] The placement unit 301 is set on the opposite side of the position where the workpiece 10 is transferred between the robot 100 and the automatic lathe 200 across the rotation center of the arm 110 of the robot 100, i.e., the axis C. In addition, the arrangement direction of the first position P1 and the second position P2 in the placement unit 301 is a direction intersecting the direction connecting the axis C and the position where the workpiece 10 is transferred in the automatic lathe 200.

[0056] In the stocker 300, if all the workpieces 11 accommodated in the tray 311 at the first position P1 are processed workpieces 12 (the tray 311 becomes the tray 312), then through the aforementioned operations of the tray moving unit 302, the tray 312 is sequentially lowered to the storage space 321 below the first position P1. The trays 312 arranged with the processed workpieces 12 are stored in the storage space 321 below the first position P1 of the stocker 300 in a state of being stacked along the height direction H.

[0057] In addition, the tray moving unit 302 of the stocker 300 moves the tray 311 at the second position P2 to the vacant first position P1 through the aforementioned operations. The trays 311 arranged with the pre-processed workpieces 11 are stored in the storage space 322 below the second position P2 of the stocker 300 in a state of being stacked along the height direction H. The tray moving unit 302 of the stocker 300 raises the uppermost tray 311 among the trays 311 stacked in the storage space 322 below the second position P2 to the second position P2. As a result, in the placement unit 301, two trays 311 are arranged and configured at the first position P1 and the second position P2 in a top-down view.

[0058] (Robot) The robot 100 has an arm 110, a hand 120, and a control unit 130. The arm 110 is fixed to the main body housing 230 of the automatic lathe 200 so as to be rotatable about an axis C extending in the vertical direction. The position of the axis C of the arm 110 fixed to the main body housing 230 is approximately in the middle, when viewed from above, between the position where the workpiece 10 is transferred to and from the automatic lathe 200 and the position where the workpiece 10 is transferred to and from the pallet 310 in the placement unit 301. The arm 110 has a plurality of joints and can move three-dimensionally by rotating around each joint.

[0059] The hand 120 is fixed to the end of the arm 110 on the side opposite to the side fixed to the automatic lathe 200. The hand 120 has two gripping parts, a first hand 121 and a second hand 122. The first hand 121 and the second hand 122 can grip the workpiece 10 by closing respectively, and separate from the workpiece 10 by opening.

[0060] The robot 100 transports the workpiece 10 gripped by the hand 120 between the placement unit 301 where the pallet 310 is placed and the automatic lathe 200 by rotating the joints of the arm 110. The hand 120 of the robot 100 transfers the workpiece 10 to and from the pallet 310 and the automatic lathe 200.

[0061] Specifically, the first hand 121 of the hand 120 grips a workpiece 11 before processing arranged at each accommodation position of the pallet 310 and transfers it to the front spindle 210 of the automatic lathe 200. On the other hand, the second hand 122 of the hand 120 receives and grips the workpiece 12 after processing from the rear spindle 220 of the automatic lathe 200 and returns to the pallet 310.

[0062] The control unit 130 controls the rotation of the joints of the arm 110 and the opening and closing of the hand 120. The control unit 130 may also be configured as a part of the control unit in the operation panel 240 of the automatic lathe 200. In addition, the control unit 130 issues an instruction to the stocker control unit 340 of the stocker 300, and the stocker control unit 340 controls the operation of the pallet moving unit 302.

[0063] Here, the positional relationship among the first position P1 where the first pallet 310 is placed, the second position P2 where the second pallet 310 is placed, and the axis C of the arm 110 of the robot 100 in the placement unit 301 will be described.

[0064] Figure 5 It is a top view showing the positional relationship among the first position P1 where the first pallet 310 is placed, the second position P2 where the second pallet 310 is placed, and the axis C of the arm 110 of the robot 100 in the placement unit 301.

[0065] As Figure 5As shown, under the control of the control unit 130, the arm 110 of the robot 100 is set to move within a range formed by a combination of a first range S1 and a second range S2, wherein the first range S1 is a range within which the hand 120 can reach all the workpieces 10 arranged on the first pallet 310 configured at the first position P1, and the second range S2 is a range within which the hand 120 can only reach a portion of the workpieces 10 arranged on the second pallet 310 configured at the second position P2, which are arranged at a position close to the first pallet 310 (specifically, for example, the portion from the upper left to the third portion downward and the portion adjacent to the right thereof from the top to the second portion).

[0066] The stocker 300 is configured with a first pallet 310 at a first position P1 of the configuration section 301, and a second pallet 310 at a second position P2. The robot 100 performs the handover of the workpieces 10 between the two pallets 310 configured in the configuration section 301 and the automatic lathe 200, and the handover order of the workpieces 10 is to first perform the handover of the workpieces 10 contained in the first pallet 310, and after the first pallet 310 is free of the workpieces 11 before processing, perform the handover of the workpieces 10 contained in the second pallet 310.

[0067] In addition, the robot 100 Figure 5 The workpiece 10 arranged at the upper left starts to be handed over, and the next workpiece 10 is handed over by shifting downward one position from the upper left. After the handover of the bottom workpiece 10 is completed, it moves to the adjacent position on the right side of the upper left to hand over the workpiece 10 adjacent to the right side of the upper left. The same is true for the future, moving downward one by one. After the handover of the bottom workpiece 10 is completed, it returns to the top and moves to the adjacent position on the right, and the workpieces 10 are handed over in this order.

[0068] In addition, the upper left position of the first pallet 310 is the position farthest from the second pallet 310, and the lower right position of the first pallet 310 is the position closest to the second pallet 310. Similarly, the upper left position of the second pallet 310 is the position closest to the first pallet 310. That is, the robot 100 sequentially delivers the workpieces 10 from the side of the first pallet 310 far from the second pallet 310, and after the delivery of the workpieces 10 on the side of the first pallet 310 close to the second pallet 310 is completed, the robot 100 starts to deliver the workpieces 10 from the side of the second pallet 310 close to the first pallet 310.

[0069] The tray moving unit 302 of the storage unit 300 is controlled by the control unit 130 of the robot 100 such that when all the workpieces 10 arranged and accommodated in the first tray 310 are in the state of being processed workpieces 12, and the hand 120 holds the unprocessed workpiece 11 arranged at the position close to the first tray 310 of the second tray 310, separates from the tray 310, and during the movement of the arm 110 toward the automatic lathe 200 side, as described above, the first tray 310 is carried out from the first position P1 to the lower storage space 321, and the second tray 310 is moved to the first position P1. Moreover, the tray moving unit 302, through the control of the control unit 130, as described above, moves the tray 310 accommodated in the lower storage space 322 to the vacant second position P2.

[0070] <Function> Figures 6 - 10 This is a top view corresponding to the operation of the workpiece loading and unloading device of the present embodiment, which Figure 5 uses to operate as described below for the workpiece loading and unloading device of the present embodiment. Figures 6 - 10

[0071] As Figure 6 shown, unprocessed workpieces 11 are arranged and accommodated in the first tray 310 and the second tray 310. In addition, processed workpieces 12 are arranged in two parts at the upper left and below, which are the farthest from the second tray 310 in the first tray 310, and the parts with × marks adjacent to these two parts ( Figure 6 in, the part directly below the processed workpiece 12) are in the vacant state without arranging workpieces 10. In addition, Figures 6 - 9 in, for the processed workpiece 12, there are slashes inside the 〇 mark, and for the unprocessed workpiece 11, there are no slashes inside the 〇 mark.

[0072] The reason for arranging the processed workpiece 12 in the first tray 310 is that the first tray 310 is arranged at the second position P2 before moving to the first position P1, and when arranged at this second position P2, the workpiece that was the unprocessed workpiece 11 is processed in the automatic lathe 200 and accommodated as the processed workpiece 12. Similarly, the reason for the part with the × mark being in the vacant state is that when the first tray 310 is arranged at the second position P2, the unprocessed workpiece 11 is arranged and transferred to the robot 100.

[0073] That is, Figure 6 the first tray 310 arranged at the first position P1 in becomes Figure 6Before the state shown, there is a second tray 310 configured at the second position P2. Moreover, the second tray 310 configured at the second position P2, in the state where the processed workpiece 12 returns to the upper left and lower parts and the robot 100 grips the workpiece 11 before processing from the part marked with an "×" adjacent to these two parts and transfers it to the robot 100, as Figure 6 shown, it moves to the first position P1 and becomes the first tray 310.

[0074] In addition, Figure 6 The state shown is that the second tray 310 previously configured at the second position P2 has moved to the first position P1, so there is a state where the next tray 310 stored in the storage space 322 below the second position P2 is configured at the second position P2.

[0075] In Figure 6 the state shown, the robot 100, through the control of the control unit 130, moves the arm 110, and the first hand 121 of the hand 120 grips the workpiece 11 before processing in the next part of the vacant part marked with an "×" on the first tray 310 ( Figure 6 in the figure is the directly below part of the part marked with an "×"). The robot 100, in the state where the first hand 121 grips the workpiece 11 before processing, through the control of the control unit 130, rotates the arm 110, thereby moving the hand 120 to the automatic lathe 200.

[0076] As an example, in the automatic lathe 200, when the machining can be completed only by the front spindle 210, the front spindle 210 grips the processed workpiece 12. The hand 120 that reaches the automatic lathe 200 through the rotation of the arm 110, through the control of the control unit 130, the second hand 122 receives the processed workpiece 12 gripped by the front spindle 210 (the front spindle 210 becomes a state of not gripping the workpiece 10). Then, through the control of the control unit 130, the first hand 121 transfers the workpiece 11 before processing that it grips to the front spindle 210.

[0077] Then, if the arm 110 rotates through the control of the control unit 130 and the hand 120 leaves the machining chamber of the automatic lathe 200, the automatic lathe 200 starts machining the workpiece 11 before processing received by the front spindle 210.

[0078] If the hand 120 reaches the first tray 310 at the first position P1 through the rotation of the arm 110, through the control of the control unit 130, the processed workpiece 12 gripped by the second hand 122 is returned to Figure 6The part marked with "×" (the part where the processed workpiece 12 was arranged before processing). Then, under the control of the control unit 130, the hand 120 rotates, and the first hand 121 holds the workpiece 11 before processing arranged in the next part of the vacant part marked with "×" ( Figure 6 The part directly below the part marked with "×" in Figure 7 The accommodating state of the workpiece 10 in the first tray 310 arranged in the placement unit 301 becomes the state shown in

[0079] That is, the processed workpieces 12 are arranged in three parts arranged on the side of the first tray 310 farthest from the second tray 310, and the part marked with "×" adjacent to these three parts ( Figure 7 The part directly below the processed workpiece 12 in

[0080] becomes a vacant state where the workpiece 10 is not arranged. As described above, under the control of the control unit 130, the arm 110 of the robot 100 moves the hand 120 to the first range S1, which is a range covering all the workpieces 10 arranged on the first tray 310 arranged at the first position P1.

[0081] Thus, by repeatedly performing a series of loading and unloading operations of holding the workpiece 11 before processing in the first tray 310 by the robot 100, loading it into the automatic lathe 200, unloading the processed workpiece 12 from the automatic lathe 200, and accommodating the processed workpiece 12 in the first tray 310, as shown in Figure 8 until the lower right part of the first tray 310 becomes the processed workpiece 12, the first tray 310 is filled with the processed workpieces 12.

[0082] As described above, under the control of the control unit 130, the arm 110 of the robot 100 enables the hand 120 to reach the second range S2, which is a range covering the workpieces 10 arranged at the position close to the first tray 310 in the second tray 310 arranged at the second position P2 (specifically, for example, the third part from the upper left to the lower and the second part from the upper to the right adjacent to it).

[0083] Therefore, after the first tray 310 is filled with the processed workpieces 12, under the control of the control unit 130 of the robot 100, the arm 110 moves the hand 120 to the second tray 310, and the first hand 121 holds the workpiece 11 before processing arranged in the upper left of the second tray 310, and through the rotation of the arm 110, the workpiece 12 is loaded into the automatic lathe 200. Thus, as shown in Figure 8 the upper left part of the second tray 310 becomes a vacant state marked with "×".

[0084] Then, by repeatedly performing a series of loading and unloading operations including gripping the workpiece 11 before processing in the second tray 310 by the robot 100, loading it into the automatic lathe 200, unloading the workpiece 12 after processing in the automatic lathe 200, and accommodating the processed workpiece 12 into the second tray 310, as Figure 9 shown, if the second part from the upper left to the lower second of the second tray 310 becomes the processed workpiece 12 and the third workpiece 11 before processing from the upper left is in the state of being unloaded by the robot 100 to the automatic lathe 200, during the period when the robot 100 is separated from the placement unit 301, the tray moving unit 302 of the stocker 300 moves the tray 310 in the following manner under the control of the control unit 130.

[0085] That is, the tray moving unit 302 lowers the first tray 310 at the first position P1 filled with the processed workpiece 12 and moves it to the storage space 321 below the first position P1. In addition, the tray moving unit 302 moves the second tray 310 at the second position P2 where the second part from the upper left to the lower second becomes the processed workpiece 12 and the third part from the upper left is in a vacant state to the first position P1 that has become vacant. The second tray 310 moved to the first position P1 becomes the first tray 310 (for the convenience of explanation, only the name of the tray 310 is changed).

[0086] Moreover, the tray moving unit 302 raises the uppermost tray 310 among the trays 310 stacked and stored in the storage space 322 below the second position P2 and moves it to the second position P2 that has become vacant. The name of the tray 310 moved to the second position P2 becomes the second tray 310.

[0087] If each tray 310 moves, it becomes Figure 6 the state shown below. Hereinafter, through the above description, the robot 100 continues to transfer the workpiece 10 between the tray 310 and the automatic lathe 200 and repeats Figures 6 to 9 the state shown, and performs the loading and unloading of the workpiece 10.

[0088] In addition, in the operation of the above example, as Figure 9 shown, when the third workpiece 11 in the second range S2 of the second tray 310 is unloaded from the second tray 310, the tray moving unit 302 moves the second tray 310 to the first position P1, but it can also be as Figure 8As shown, in the state where the first workpiece 11 in the second range S2 of the second tray 310 is removed from the second tray 310, or the second workpiece 11 in the second range S2 of the second tray 310 is removed from the second tray 310, the tray moving unit 302 moves the first tray 310 downward to move the second tray 310 to the first position P1.

[0089] In short, as long as all the workpieces 10 accommodated in the first tray 310 arranged at the first position P1 become processed workpieces 11 and the unprocessed workpieces 11 accommodated in the second range S2 of the second tray 310 arranged at the second position P2 are removed, regardless of the number of processed workpieces 12 accommodated in the second range S2, the tray moving unit 302 can move the second tray 320 to the first range S1.

[0090] If the storage space 322 below the first position P1 is filled with trays 312 containing processed workpieces 12 through the above-described transfer of workpieces 10 and movement of the trays 310, then manually by the operator, the trays 312 stacked in the storage space 322 below the first position P1 are moved through the opening 331 to the unloading cart 420 arranged on the side of the magazine 300, making the storage space 321 below the first position P1 vacant. Then, after the cart 420 carrying the trays 312 containing processed workpieces 12 is moved to another place and the trays 312 containing workpieces 12 are unloaded, trays 311 containing unprocessed workpieces 11 are loaded.

[0091] In addition, if there are no more trays 311 containing unprocessed workpieces 11 stored in the storage space 322 below the second position P2, then manually by the operator, the trays 311 containing unprocessed workpieces 12 placed in a stacked state on the loading cart 410 arranged on the side of the magazine 300 are moved through the opening 332 to be stored in the storage space 322 below the second position P2. Then, the cart 410 carrying the trays 311 containing unprocessed workpieces 11 moves to the side of the unloading opening 331 on the unloading side and serves as the unloading cart 420. In addition, there is no difference between the loading cart 410 and the unloading cart 420, except that they are distinguished in description by using one cart for loading or unloading.

[0092] As described in detail above, in the workpiece loading / unloading device (robot 100 and stocker 300) and its control method according to the present embodiment, in a state where two pallets, i.e., a first pallet 310 and a second pallet 310, are arranged in the pallet-side configuration unit 301 for exchanging the workpiece 10 with the automatic lathe 200, even when performing a loading / unloading operation of gripping the workpiece 11 before machining disposed at a specified position on the pallet 310 and returning the machined workpiece 12 to the original position of the pallet 310 where it was disposed before machining, compared with a structure in which only one pallet 310 is arranged in the configuration unit 301, the standby time of the robot 100 during pallet replacement can be eliminated.

[0093] In addition, as Figure 5 shown, in the workpiece loading / unloading device and its control method according to the present embodiment, the arm portion 110 of the robot 100 is set to move within a range formed by combining a first range S1 and a second range S2 through the control of the control unit 130. The first range S1 is a range in which the hand portion 120 can reach all the workpieces 10 arranged on the first pallet 310 disposed at the first position P1, and the second range S2 is a range in which the hand portion 120 can only reach a part of the workpieces 10 arranged at positions (specifically, for example, the part from the upper left downward to the third and the part adjacent to its right up to the second from the top) close to the first pallet 310 among the workpieces 10 arranged on the second pallet 310 disposed at the second position P2.

[0094] Therefore, the robot 100 only needs to be able to move within the range of the circle R1 indicated by the single-dot chain line in Figure 5 . That is, the movement range of the robot 100 can be made smaller than that of the circle R2 indicated by the single-dot chain line in Figure 5 . The circle R2 indicated by the single-dot chain line in Figure 5 is a range in which the hand portion 120 can reach all the workpieces 10 arranged on the first pallet 310 and all the workpieces 10 arranged on the second pallet 310 among the two pallets arranged in the configuration unit 301.

[0095] Thereby, the workpiece loading / unloading device and its control method according to the present embodiment can set the operation area on the pallet side of the robot 100 to be narrow, reducing the movement of the arm portion 110. Therefore, the workpiece loading / unloading device and its control method according to the present embodiment can shorten the length of the arm portion 110 (without the need to make it longer). In addition, since there is no need to increase the rigidity of the portion supporting the arm portion 110, the weight of the robot 100 can be reduced (preventing the robot 100 from becoming large due to weight increase), and the cost of the robot 100 can be lowered (preventing cost increase).

[0096] When the time required to process the workpiece 11 by means of the automatic lathe 200 is shorter than the working time of the robot 100, the working time of the robot 100 has a significant impact on the cycle time. The workpiece loading and unloading device and its control method according to the present embodiment can reduce the movement of the arm 110, and can also shorten the cycle time of the movement of the robot 100 by rotating the arm 110 even when the time required to process the workpiece 11 by means of the automatic lathe 200 is short.

[0097] In addition, in the workpiece loading and unloading device and its control method according to the present embodiment, under the condition that the handover position of the workpiece 10 on the automatic lathe 200 side is set within the circle R1 of the operating range of the robot 100, the arm 110 only needs to be formed to a length that can reach the range composed of the first range S1 and the second range S2 from the axis C as the rotation center to the hand 120, and the arm 110 can be shortened.

[0098] Figure 10 It is a top view corresponding to showing the state where the arrangement of the stocker 300 is offset when there is an obstacle 500 within the range where the stocker 300 is to be arranged. Figure 5 equivalent top view.

[0099] In the workpiece loading and unloading device and its control method according to the present embodiment, it is sufficient that the hand 120 of the robot 100 can reach the entire area of the first tray 310, which is the first range S1, and a part of the area of the second tray 310, which is the second range S2, arranged in the arrangement part 301.

[0100] Therefore, as Figure 10 shown, even when there are obstacles 500 such as factory structures (columns, etc.) or other devices within the range where the stocker 300 is originally to be arranged, the workpiece loading and unloading device and its control method according to the present embodiment can make the stocker 300 offset and arranged at a position avoiding the obstacle 500 in such a way that the hand 120 of the robot 100 can reach the range composed of the entire area of the first tray 310, which is the first range S1, and a part of the area of the second tray 310, which is the second range S2. Therefore, the workpiece loading and unloading device and its control method according to the present embodiment can improve the arrangement freedom of the automatic lathe 200, the robot 100, and the stocker 300.

[0101] Further, in the workpiece loading and unloading device and its control method according to the present embodiment, the arrangement direction of the first position P1 and the second position P2 in the configuration unit 301 is set to be a direction intersecting with the direction connecting the shaft C and the position where the workpiece 10 is transferred in the automatic lathe 200. Thus, compared with the case where the arrangement direction of the first position P1 and the second position P2 at the configuration unit 301 is set to be along the direction connecting the shaft C and the position where the workpiece 10 is transferred in the automatic lathe 200 (substantially parallel), it is possible to reduce the distance difference between the workpiece 10 configured farthest from the position where the workpiece 10 is transferred to and from the automatic lathe 200 and the workpiece 10 configured closest in the range formed by combining the first range S1 and the second range S2.

[0102] Thus, it is possible to suppress the deviation of the moving distance of the arm portion 110, and when the time required for machining the workpiece 11 by the automatic lathe 200 is shorter than the working time of the robot 100, it is possible to suppress the deviation of the working time of the robot 100.

[0103] In the workpiece loading and unloading device and its control method according to the present embodiment, in addition to the configuration unit 301, there are also a storage space 321 for storing the tray 312 containing the machined workpiece 12 and a storage space 322 for storing the tray 311 containing the workpiece 11 before machining. However, the workpiece loading and unloading device and its control method of the present invention only need to have the configuration unit 301 and the tray moving unit 302 in the stocker 300, and the above storage spaces 321 and 322 may not be provided.

[0104] The workpiece loading and unloading device and its control method according to the present embodiment are applicable to the robot 100 having an arm portion 110 including multiple joints. However, in the workpiece loading and unloading device and its control method of the present invention, as long as it is a transfer mechanism that moves the hand portion 120 through a link mechanism in the same way as the arm portion 110 of the robot 100 having an arm portion 110 including multiple joints, this transfer structure can also be applied in place of the robot.

[0105] In the workpiece loading and unloading device and its control method according to the present embodiment, during the period when the robot 100 holds the workpiece 10 in the second range S2, separates from the tray 310, and moves from the tray 310 side toward the automatic lathe 200 side, under the control of the control unit 130, the tray moving unit 302 moves the second tray 310 to the first position P1. Before the robot 100 returns to the tray 310 side, the second tray 310 may not reach the first position P1, and it is sufficient that the second tray 310 is in a state of moving at least slightly toward the first position P1. However, the amount of this movement needs to be such that the workpiece 11 before machining grasped by the hand portion 120 is within the range formed by combining the first range S1 and the second range S2.

[0106] The above-described embodiment illustrates the case where the automatic lathe 200 completes machining with the workpiece 10 held by the front spindle 210. The workpiece loading and unloading device and its control method of the present invention may also be such that the workpiece 10 machined in the state held by the front spindle 210 is transferred to the rear spindle 220, and when machining is completed in the state held by the rear spindle 220, the machine tool (automatic lathe 200) and the workpiece loading and unloading device (robot 100, stocker 300) are configured such that the hand 121 receives the machined workpiece 120 from the rear spindle 220 and transfers the workpiece 11 before machining to the front spindle 210.

[0107] The workpiece loading and unloading device and its control method of the present embodiment apply the automatic lathe 200 as an example of a machine tool. However, the machine tool in the loading and unloading device and its control method of the present invention is not limited to an automatic lathe and can be applied to machine tools for various plastic working of workpieces.

[0108] Cross-reference to related applications This application claims priority based on Japanese Patent Application No. 2022-170609 filed with the Japan Patent Office on October 25, 2022, and the entire disclosure of this application is incorporated herein by reference in its entirety.

Claims

1. A workpiece loading and unloading device, characterized in that, it has: a configuration unit configured with two pallets, in which a plurality of workpieces are arranged and accommodated, a pallet moving unit that moves the pallets arranged in the configuration unit, an arm unit that moves between a machine tool for processing the workpiece, a hand unit that holds the workpiece and transfers the workpiece between the pallet and the machine tool, and a control unit that controls the pallet moving unit, the arm unit, and the hand unit; In a top-down view, the configuration unit arranges and configures two pallets, namely a first pallet arranged at a first position and a second pallet arranged at a second position adjacent to the first position, the control unit controls the arm unit to move within a range composed of a first range and a second range. The first range is the range where the hand unit can reach all the workpieces arranged on the first pallet, and the second range is the range where the hand unit can only reach a part of the workpieces arranged on the second pallet and located at positions close to the first pallet, When the first pallet contains all the workpieces that can be arranged and accommodated, and the hand unit holds the workpieces arranged at positions close to the first pallet on the second pallet, and during the period when the arm unit is separated from the pallet, the control unit controls the pallet moving unit to move the second pallet towards the first position.

2. The workpiece loading and unloading device according to claim 1, characterized in that, When the first pallet contains all the workpieces that can be arranged and accommodated, and the hand unit holds the workpieces arranged at positions close to the first pallet on the second pallet, and during the period when the arm unit is separated from the pallet, the control unit controls the movement of the pallet so as to move the first pallet out of the first position and move the second pallet to the first position.

3. The workpiece loading and unloading device according to claim 1 or 2, characterized in that, After the control unit makes the pallet moving unit move the second pallet to the first position, it makes a new pallet move to the second position.

4. The workpiece loading and unloading device according to claim 1 or 2, wherein, the arm unit is formed to have a length from the rotation center to the range where the hand unit can reach the range composed of the first range and the second range.

5. A control method for a workpiece loading and unloading device, which controls a workpiece loading and unloading device, characterized in that, the workpiece loading and unloading device has: a configuration unit configured with two pallets, in which a plurality of workpieces are arranged and accommodated, a pallet moving unit that moves the pallets arranged in the configuration unit, an arm unit that moves between a machine tool for processing the workpiece, and a hand unit that holds the workpiece and transfers the workpiece between the pallet and the machine tool; In a top-down view, the configuration unit arranges and configures two pallets, namely a first pallet arranged at a first position and a second pallet arranged at a second position adjacent to the first position, The arm is controlled to move within a range formed by combining a first range and a second range. The first range is the range within which the hand can reach all the workpieces arranged on the first tray, and the second range is the range within which the hand can only reach a part of the workpieces arranged on the second tray and located at positions close to the first tray. When all the workpieces that can be arranged and accommodated are accommodated in the first tray, and the hand holds the workpieces arranged at positions close to the first tray on the second tray, during the period when the arm is separated from the tray, the tray moving part is controlled to move the second tray towards the first position.

6. The control method of the workpiece loading and unloading device according to claim 5, wherein, When all the workpieces that can be arranged and accommodated are accommodated in the first tray, and the hand holds the workpieces arranged at positions close to the first tray on the second tray, during the period when the arm is separated from the tray, the tray moving part is controlled to remove the first tray from the first position and move the second tray towards the first position.

Images