Transport system
The transport system addresses fretting by controlling a block's movement to prevent lubricant loss, ensuring smooth operation and reducing wear without affecting the robot's efficiency.
Patent Information
- Application Number
- JP2024055873
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-03-29
- Publication Date
- 2025-10-10
AI Technical Summary
The movement mechanism in existing conveyance systems causes fretting due to vibrations that remove lubricants from contact surfaces between rolling elements and rails, leading to wear when the robot arm and drive mechanism are operated with the base at a predetermined position.
A transport system with a control unit that positions a block at a set stop position and performs a first operation of moving it back and forth between the stop position and a predetermined distance, using a block driving unit to suppress fretting without affecting the takt time of the robot arm.
Suppresses fretting occurrences by drawing lubricant back into contact surfaces, reducing wear without impacting the robot's operational efficiency.
Smart Images
Figure 2025153400000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to a transport system. [Background technology]
[0002] A transfer system for transferring glass substrates and the like is described in Patent Document 1. The transfer system in this document includes a robot arm that moves a hand in a first direction along the horizontal direction, a drive mechanism that moves the robot arm in a second direction along the vertical direction and rotates the robot arm around a rotation axis along the vertical direction, and a movement mechanism that moves the robot arm in a movement direction that is a third direction along the horizontal direction and perpendicular to the first direction. The movement mechanism includes a rail that extends in the third direction, a base supported movably along the rail, and a drive unit that moves the base along the rail. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Japanese Patent Application Publication No. 07-263518 Summary of the Invention [Problem to be solved by the invention]
[0004] The movement mechanism used in the conveyance system described in Patent Document 1 may include a rail extending in a third direction, a base attached to the rail via a large number of rolling elements that circulate endlessly, and a base drive unit that moves the base in three directions. In this case, a drive mechanism is fixed to the base. The movement of the base in the third direction causes the robot arm to move in the third direction via the drive mechanism.
[0005] In a conveying system such as that described in Patent Document 1, the robot arm and drive mechanism may be operated with the third direction position of the robot arm set to a predetermined position to convey a glass substrate. That is, when conveying a glass substrate, there is a usage situation in which the robot arm and drive mechanism are operated with the base stopped at a predetermined position without operating the moving mechanism. In such a usage situation, vibrations generated when the robot arm and drive mechanism operate and minute movements for aligning the base are transmitted to the rolling elements via the base, which may remove lubricants such as grease from the contact surfaces between the rolling elements and the rails and base, causing fretting on the contact surfaces between the rolling elements and the rails and base.
[0006] In view of the above problems, an object of the present invention is to, in a transport system equipped with a movement mechanism capable of moving a robot arm in a movement direction extending along the horizontal direction, suppress the occurrence of fretting in the movement mechanism when using the robot arm, even when the position of the robot arm in the movement direction is set to a predetermined position. [Means for solving the problem]
[0007] In order to solve the above-mentioned problems, the transport system of the present invention is a transport system for transporting a workpiece from a first mounting section to a second mounting section, the transport system comprising a transport robot having a robot arm that moves a hand that holds the workpiece in a first direction along a horizontal direction, a first drive mechanism that moves the robot arm in a second direction along a vertical direction, and a second drive mechanism that rotates the first drive mechanism around a rotation axis that is along the second direction, and a movement mechanism that moves the transport robot in a third direction that is along the horizontal direction and perpendicular to the first direction, the movement mechanism including a rail section that extends in the third direction, a block to which the transport robot is fixed and that is attached to the rail section via a number of rolling elements that circulate endlessly, and a mechanism that moves the block in the third direction. a moving mechanism having a block driving unit for moving the block to a set stop position, and a control unit for controlling the robot arm, the first driving mechanism, the second driving mechanism, and the moving mechanism, wherein the control unit drives the block driving unit to position the block at a set stop position in a setting stage before transporting the work from the first loading section to the second loading section, and drives the block driving unit to perform a first operation of moving the block back and forth between the stop position and a position a predetermined distance away according to the operating status of the transport robot in a work stage of transporting the work from the first loading section to the second loading section. [Brief explanation of the drawings]
[0008] [Figure 1] FIG. 1 is a plan view of the transport system. [Figure 2] FIG. 2 is a side view of the transport system shown in FIG. [Figure 3] FIG. 3 is a plan view of the movement mechanism. [Figure 4] FIG. 4 is a diagram illustrating the relationship between the rail portion and the block. [Figure 5] FIG. 5 is a block diagram of the transport system. DETAILED DESCRIPTION OF THE INVENTION
[0009] An embodiment of the present invention will be described with reference to the drawings. In the following description, the case where the workpiece to be transported is a glass substrate for a liquid crystal display (hereinafter referred to as "substrate") will be mainly described. The substrate W is a rectangular flat plate. Fig. 1 is a plan view of the transport system. Fig. 2 is a side view of the transport system shown in Fig. 1. Fig. 3 is a plan view of the movement mechanism. Fig. 4 is a diagram explaining the relationship between the rail portion and the block. Fig. 5 is a block diagram of the transport system.
[0010] (Overall configuration of the transport system) The transfer system 100 of this embodiment is incorporated into a liquid crystal display manufacturing line for use. As shown in Fig. 1, the transfer system 100 transfers a glass substrate W from a first mounting part 200 to a second mounting part 300. In the following description, for convenience, three mutually orthogonal axes are referred to as the X-axis, Y-axis, and Z-axis. The Z-axis direction (second direction) is a direction along the up-down direction. The X-axis direction (first direction) and the Y-axis direction (third direction) are directions along the horizontal direction.
[0011] 1 and 2, the transfer system 100 includes a transfer robot 2, a movement mechanism 3 that moves the transfer robot 2 in the Y-axis direction, and a control unit 8. The transfer robot 2 includes a robot arm 4, a first drive mechanism 5, and a second drive mechanism 6.
[0012] The robot arm 4 moves the hand 41 that holds the substrate W in the X-axis direction. The robot arm 4 includes an arm section 42 to the tip of which the hand 41 is connected, and an arm driver 43 that extends and contracts the arm section 42 to move the hand 41 in the X direction. In this embodiment, the hand 41 includes two forks 411, and the substrate W is placed on the forks 411. The two forks 411 protrude horizontally and are arranged parallel to each other with a gap between them. The arm section 42 is a multi-joint arm that extends and contracts in the X direction. The arm driver 43 is a servo motor or the like.
[0013] The first drive mechanism 5 moves the robot arm 4 in the Z-axis direction. The first drive mechanism 5 includes a base unit 51 to which the robot arm 4 is fixed, a support frame 52 that supports the base unit 51 so that it can be raised and lowered, and a first drive unit 53 that moves the base unit 51 in the Z-axis direction relative to the support frame 52. The first drive unit 53 includes a motor that serves as a drive source, and a power transmission unit that transmits the power of the motor to the base unit 51.
[0014] The second drive mechanism 6 rotates the first drive mechanism 5 around a rotation axis along the Z-axis direction. The second drive unit 61 is disposed below the support frame 52. The second drive unit 61 includes a motor as a drive source and a power transmission unit that transmits the power of the motor to the support frame 52.
[0015] As shown in FIGS. 1 to 4, the movement mechanism 3 includes a rail section 31 extending in the Y-axis direction, a block 32 to which the transport robot 2 is fixed and which is attached to the rail section 31 via a large number of balls 34 serving as rolling elements that circulate endlessly, and a block driving section 33 that moves the block 32 in the Y-axis direction. In this embodiment, two rail sections 31 are arranged in parallel. A block 32 is provided for each rail section 31. The two blocks 32 are connected via a table member 35. The transport robot 2 is fixed to the two blocks 32 via the table member 35. A lubricant such as grease is applied around the balls 34. The block driving section 33 includes a motor as a drive source and a power transmission section that transmits the power of the motor to the block 32.
[0016] 5, the control unit 8 controls the arm driver 43 of the robot arm 4 in response to a command from the host device 500. By driving the arm driver 43, the arm unit 42 extends and retracts in the X-axis direction, and the hand 41 moves in the X-axis direction. The control unit 8 can also drive the arm driver 43 to perform arm operation, moving the arm unit 42 from a first position 4A where the arm unit 42 is retracted to a second position 4B where the arm unit 42 is extended, and back to the first position 4A where the arm unit 42 is retracted, in that order.
[0017] The control unit 8 controls the first drive unit 53 of the first drive mechanism 5 in response to a command from the host device 500. As a result, the first drive unit 53 is driven to move the base unit 51 in the Z-axis direction, and therefore the robot arm 4 moves in the Z-axis direction. The control unit 8 controls the second drive unit 61 of the second drive mechanism 6 in response to a command from the host device 500. As a result, the second drive unit 61 is driven to rotate the support frame 52, and therefore the robot arm 4 rotates about a rotation axis along the Z-axis direction. The control unit 8 controls the block drive unit 33 of the movement mechanism 3 in response to a command from the host device 500. As a result, the block drive unit 33 is driven to move the block 32 in the Y-axis direction, and therefore the robot arm 4 moves in the Y-axis direction.
[0018] (Transport system operation) The operation of the transport system 100 will be described. First, in a setting stage before the substrate W is transported from the first receiver 200 to the second receiver 300, a stop position in the Y-axis direction of the transport robot 2 is set. Specifically, in the setting stage before the substrate W is transported from the first receiver 200 to the second receiver 300, the control unit 8 controls the block driving unit 33 of the movement mechanism 3 to position the block 32 at the set stop position. This sets the stop position of the transport robot 2 in the Y-axis direction.
[0019] Next, in the operation stage of transporting the substrate W from the first receiver 200 to the second receiver 300, when the control unit 8 receives a command to transport the substrate W from the host device 500, it controls the first drive unit 53 to adjust the height in the Z axis direction of the hand 41 of the robot arm 4 to a position slightly lower than the height of the first receiver 200. At this time, the arm unit 42 is located at the retracted first position 4A. Thereafter, the control unit 8 drives the arm drive unit 43 to move the arm unit 42 from the retracted first position 4A to the extended second position 4B in that order. When the arm unit 42 is located at the extended second position 4B, the control unit 8 controls the first drive unit 53 to move the robot arm 4 upward. As a result, the substrate W is placed on the fork 411 of the hand 41. Thereafter, the control unit 8 drives the arm driving unit 43 to move the arm unit 42 from the second position 4B where the arm unit 42 is extended to the first position 4A where the arm unit 42 is retracted, in that order.
[0020] When the arm unit 42 is located at the extended first position 4A, the control unit 8 controls the second driving unit 61 to rotate the robot arm 4 about a rotation axis along the Z-axis direction, and controls the first driving unit 53 to adjust the height of the hand 41 of the robot arm 4 in the Z-axis direction to a position slightly higher than the height of the second mount unit 300. Thereafter, the control unit 8 drives the arm driving unit 43 to move the arm unit 42 from the retracted first position 4A to the extended second position 4B, in that order. When the arm unit 42 is located at the extended second position 4B, the control unit 8 controls the first driving unit 53 to move the robot arm 4 downward. As a result, the substrate W is placed on the second mount unit 300. When the substrate W is placed on the second receiver 300, the control unit 8 drives the arm driver 43 to move the arm 42 from the second position 4B where the arm 42 is extended to the first position 4A where the arm 42 is retracted, in that order. Thereafter, the control unit 8 controls the second driver 61 to rotate the robot arm 4 and waits for a command from the host device 500. When the control unit 8 receives the next command to transport the substrate W from the host device 500, it controls the arm driver 43, first driver 53, and second driver 61 in the same manner as described above to transport the substrate W from the first receiver 200 to the second receiver 300.
[0021] Here, in the transfer system 100 of this embodiment, the control unit 8 does not actively operate the moving mechanism 3 to transfer the substrate W from the first receiver 200 to the second receiver 300. That is, the transfer robot 2 transfers the substrate W from the first receiver 200 to the second receiver 300 while the block 32, to which the robot arm 4 is fixed, is stopped at a predetermined stop position. Therefore, since the transfer robot 2 operates while the block 32 is stopped at the stop position, vibrations generated when the transfer robot 2 operates are transmitted to the ball 34 via the block 32, which may remove lubricant from the contact surfaces between the ball 34 and the rail portion 31 and block 32, and may cause fretting on the contact surfaces between the ball 34 and the rail portion 31 and block 32. Therefore, in the transport system 100 of this embodiment, during the work stage of transporting the substrate W from the first mounting section 200 to the second mounting section 300, the control section 8 drives the block driving section 33 according to the operating status of the transport robot 2 to perform a first operation of moving the block 32 back and forth between a stop position and a position a predetermined distance away, thereby suppressing the occurrence of fretting.
[0022] Specifically, in the operation stage of transporting the substrate W from the first receiver 200 to the second receiver 300, the control unit 8 drives the block driving unit 33 to perform a first operation once to reciprocate the block 32 between a stop position and a position a predetermined distance away, after at least one of an arm operation for placing the substrate W placed on the first receiver 200 onto the hand 41 and an arm operation for placing the substrate W placed on the hand 41 onto the second receiver 300. That is, the control unit 8 performs the first operation once in one cycle of transporting the substrate W from the first receiver 200 to the second receiver 300, while the robot arm 4 is not operating.
[0023] Here, if the diameter of the ball 34 is D and the predetermined distance is L, the predetermined distance satisfies "L = πD." That is, when the block 32 moves the predetermined distance L, the ball 34 makes one rotation.
[0024] (Action and effect) In the transport system 100 of this embodiment, in a setting stage before the substrate W is transported from the first receiver 200 to the second receiver 300, the control unit 8 controls the block driving unit 33 of the moving mechanism 3 to position the block 32 at a set stop position, and in a working stage of transporting the substrate W from the first receiver 200 to the second receiver 300, after at least one of an arm operation for placing the substrate W placed on the first receiver 200 on the hand 41 and an arm operation for placing the substrate W placed on the hand 41 on the second receiver 300, the control unit 8 drives the block driving unit 33 to perform a first operation once to reciprocate the block 32 between a position a predetermined distance away from the stop position. The lubricant removed from the contact surface with the block 32 is caught in the contact surfaces between the ball 34 and the rail portion 31 and the block 32, thereby suppressing the occurrence of fretting. Furthermore, even in a usage situation in which the robot arm 4 operates with the block 32 set to the stop position, the control unit 8 executes the first operation while the robot arm 4 is not operating, thereby suppressing the occurrence of fretting without affecting the takt time of the robot arm 4. Furthermore, the control unit 8 executes the first operation once in one cycle of transporting the substrate W from the first mount part 200 to the second mount part 300, thereby reducing the effect on the takt time of the transport robot 2.
[0025] In the conveyance system 100 of this embodiment, where D is the diameter of the ball 34 and L is the predetermined distance, the predetermined distance satisfies "L = πD." As a result, the lubricant removed from the contact surfaces between the ball 34 and the rail portion 31 and the block 32 is drawn into the contact surfaces between the ball 34 and the rail portion 31 and the block 32, thereby further suppressing the occurrence of fretting and shortening the time for the first operation.
[0026] (Other embodiments) In the operation stage of transporting the substrate W from the first receiver 200 to the second receiver 300, the control unit 8 may drive the block driving unit 33 to perform a first operation of reciprocating the block 32 between a stop position and a position a predetermined distance away, after at least one of an arm operation for placing the substrate W placed on the first receiver 200 onto the hand 41 and an arm operation for placing the substrate W placed on the hand 41 onto the second receiver 300. In other words, the control unit 8 may perform the first operation after each of an arm operation for placing the substrate W placed on the first receiver 200 onto the hand 41 and an arm operation for placing the substrate W placed on the hand 41 onto the second receiver 300.
[0027] The control unit 8 may execute the first operation when the operation of the transport robot 2 is stopped during the work stage of transporting the substrate W from the first receiver 200 to the second receiver 300. In other words, the control unit 8 may execute the first operation when no command for the transport robot 2 has been received from the higher-level device 500.
[0028] In the above embodiment, the hand 41 includes the fork 411 on which the substrate W is placed, but the hand 41 may also include a suction portion that suction-holds the substrate W. That is, the substrate W may be suction-held by the hand 41.
[0029] In the above embodiment, one robot arm 4 is provided, but a plurality of robot arms 4 may be provided.
[0030] In the above embodiment, two rail portions 31 are arranged, but the number of rail portions 31 is not limited to two. The number of rail portions 31 may be one, or three or more.
[0031] In the above embodiment, the rolling elements are balls 34, but the rolling elements may also be rollers.
[0032] The present technology can be configured as follows.
[0033] (1) In a conveying system that conveys a workpiece from a first placement unit to a second placement unit, a transfer robot including a robot arm that moves a hand that holds the workpiece in a first direction along a horizontal direction, a first drive mechanism that moves the robot arm in a second direction along a vertical direction, and a second drive mechanism that rotates the first drive mechanism around a rotation axis that extends along the second direction; a movement mechanism that moves the transport robot in a third direction that is along a horizontal direction and perpendicular to the first direction, the movement mechanism including a rail portion extending in the third direction, a block to which the transport robot is fixed and which is attached to the rail portion via a number of rolling elements that circulate endlessly, and a block drive unit that moves the block in the third direction; a control unit that controls the robot arm, the first drive mechanism, the second drive mechanism, and the movement mechanism; Equipped with The control unit In a setting stage before the workpiece is transported from the first placement unit to the second placement unit, the block driving unit is driven to position the block at a set stop position; A transport system characterized in that, during a work stage in which the workpiece is transported from the first loading section to the second loading section, the block driving section is driven in accordance with the operating status of the transport robot to perform a first operation in which the block is moved back and forth between the stop position and a position a predetermined distance away.
[0034] This allows the robot arm to operate even when the block is set to the stop position. The control unit executes the first operation while the transport robot is not operating, and therefore, the occurrence of fretting can be suppressed without affecting the takt time of the transport robot.
[0035] (2) The conveying system described in (1) is characterized in that the control unit performs the first operation when the operation of the conveying robot is stopped during the work stage of transporting the workpiece from the first placement section to the second placement section.
[0036] As a result, even in a usage situation in which the robot arm operates with the block set in a stopped position, the control unit executes the first operation while the operation of the transport robot is stopped, thereby suppressing the occurrence of fretting without affecting the takt time of the transport robot.
[0037] the robot arm includes an arm unit having the hand connected to a tip end thereof, and an arm driving unit that extends and retracts the arm to move the hand in a first direction; the control unit is capable of driving the arm driving unit to perform arm operation in which the arm unit moves in the order of a first position in which the arm unit is retracted, a second position in which the arm unit is extended, and the first position in which the arm unit is retracted, The conveying system described in (1) is characterized in that, during the work stage of transporting the work from the first loading section to the second loading section, the control unit executes the first operation after at least one of the arm operation for placing the work placed on the first loading section onto the hand and the arm operation for placing the work placed on the hand onto the second loading section.
[0038] As a result, even in a usage situation in which the robot arm operates with the block set in a stop position, the control unit executes the first operation when the robot arm is not operating, thereby suppressing the occurrence of fretting without affecting the takt time of the robot arm.
[0039] (4) The control unit controls the arm operation for placing the workpiece placed on the first placement unit onto the hand, and the arm operation for placing the workpiece placed on the hand onto the second placement unit, in a work stage of transporting the workpiece from the first placement unit to the second placement unit. The transfer system according to (3), wherein the first operation is performed once after one of the arm operations for the purpose of transferring the first and second objects.
[0040] As a result, the control unit executes the first operation once in the work stage of transporting the workpiece from the first placement unit to the second placement unit, thereby reducing the effect on the takt time of the transport robot.
[0041] If the diameter of the rolling element is D and the predetermined distance is L, then L=πD The transport system according to any one of (1) to (3) above,
[0042] This allows the lubricant that is removed from the contact surfaces between the rolling element and the rail portion and block to be drawn into the contact surfaces between the rolling element and the rail portion and block, thereby further suppressing the occurrence of fretting and shortening the time required for the first operation. [Explanation of symbols]
[0043] 100...transport system, 2...transport robot, 3...movement mechanism, 4...robot arm, 4A...first position, 4B...second position, 5...first drive mechanism, 6...second drive mechanism, 8...control unit, 31...rail unit, 32...block, 33...block drive unit, 34...ball, 41...hand, 42...arm unit, 43...arm drive unit, 51...base unit, 52...support frame, 53...first drive unit, 61...second drive unit, 200...first placement unit, 300...second placement unit, 500...host equipment.
Claims
1. In a conveying system that conveys a workpiece from a first placement unit to a second placement unit, a transfer robot including a robot arm that moves a hand that holds the workpiece in a first direction along a horizontal direction, a first drive mechanism that moves the robot arm in a second direction along a vertical direction, and a second drive mechanism that rotates the first drive mechanism around a rotation axis that extends along the second direction; a movement mechanism that moves the transport robot along a horizontal direction and in a third direction perpendicular to the first direction, the movement mechanism including a rail portion extending in the third direction, a block to which the transport robot is fixed and which is attached to the rail portion via a large number of rolling elements that circulate endlessly, and a block drive unit that moves the block in the third direction; a control unit that controls the robot arm, the first drive mechanism, the second drive mechanism, and the movement mechanism; Equipped with The control unit In a setting stage before the workpiece is transported from the first placement unit to the second placement unit, the block driving unit is driven to position the block at a set stop position; A transport system characterized in that, during a work stage in which the workpiece is transported from the first loading section to the second loading section, the block drive unit is driven depending on the operating status of the transport robot to perform a first operation in which the block is moved back and forth between the stop position and a position a predetermined distance away.
2. The conveying system according to claim 1, characterized in that the control unit performs the first operation while the operation of the conveying robot is stopped during the work stage of conveying the work from the first placement section to the second placement section.
3. the robot arm includes an arm unit having the hand connected to a tip end thereof, and an arm driving unit that extends and contracts the arm to move the hand in a first direction; the control unit is capable of driving the arm driving unit to perform arm operation in which the arm unit moves in the order of a first position in which the arm unit is retracted, a second position in which the arm unit is extended, and the first position in which the arm unit is retracted, The conveying system described in claim 1, characterized in that, during a work stage in which the work is transported from the first loading section to the second loading section, the control unit executes the first operation after at least one of the arm operation for placing the work placed on the first loading section onto the hand and the arm operation for placing the work placed on the hand onto the second loading section.
4. The conveying system described in claim 3, characterized in that, during the work stage of transporting the work from the first loading section to the second loading section, the control unit executes the first operation once after either the arm operation for placing the work placed on the first loading section onto the hand, or the arm operation for placing the work placed on the hand onto the second loading section.
5. If the diameter of the rolling element is D and the predetermined distance is L, then L = πD 4. The transport system according to claim 1, wherein the following is satisfied:
Citation Information
Patent Citations
Method and apparatus for transferring semiconductor wafer, and wafer treatment method
JP1995263518A