Substrate transfer robot

Abstract

This substrate transfer robot comprises a hand (30), fixed support parts (33, 34), a movable support part (35), a drive part (36), a force sensor (50), and a control part. The fixed support parts (33, 34) contact a workpiece (W) held in the hand (30). The movable support part (35), working together with the fixed support parts (33, 34), holds the workpiece (W) therebetween in the hand (30). The drive part (36) moves the movable support part (35). The force sensor (50) detects a force imparted to the movable support part (35). The control part controls the movement of the movable support part (35) by the drive part (36) on the basis of a detection result from the force sensor (50).

Description

Substrate transfer robot

[0001] This disclosure relates to a substrate transfer robot.

[0002] Conventionally, substrate transfer robots are known. For example, Japanese Patent Application Laid-Open No. 2002-184853 discloses a wafer gripping device attached to a wafer transfer robot that transfers wafers. The wafer gripping device described in Japanese Patent Application Laid-Open No. 2002-184853 grips the peripheral edge of the wafer by moving a pressing element that presses the peripheral edge of the wafer by an air cylinder, and supports the wafer.

[0003] Japanese Patent Application Laid-Open No. 2002-184853

[0004] Here, when gripping the peripheral edge of a wafer as a workpiece by moving a pressing element as in the wafer gripping device described in Japanese Patent Application Laid-Open No. 2002-184853, in order to suppress the increase in the force applied to the workpiece by the pressing element when the pressing element abuts against the workpiece, an operation of adjusting the magnitude of the force applied to the workpiece is performed by adjusting the movement of the pressing element by a driving unit such as an air cylinder. Such an operation of adjusting the movement by the driving unit is a burden on the operator. Therefore, it is desired to easily adjust the force applied to the workpiece when sandwiching and holding the workpiece by reducing the burden on the operator.

[0005] This disclosure has been made to solve the above problems, and one object of this disclosure is to provide a substrate transfer robot capable of easily adjusting the force applied to a workpiece when sandwiching and holding the workpiece.

[0006] To achieve the above objective, a substrate transport robot according to one aspect of this disclosure includes: a hand for holding a workpiece including at least one of a substrate and a jig for processing the substrate; a fixed support portion positioned on the hand and in contact with the workpiece held by the hand; a movable support portion that holds the workpiece together with the fixed support portion in the hand; a drive unit for moving the movable support portion; a force sensor for detecting the force applied to the movable support portion; and a control unit that controls the movement of the movable support portion by the drive unit based on the detection result of the force sensor.

[0007] As described above, a substrate transfer robot according to one aspect of this disclosure includes a force sensor that detects the force applied to the movable support, and a control unit that controls the movement of the movable support by the drive unit based on the detection result of the force sensor. This allows the force sensor to detect the magnitude of the force applied to the movable support when gripping and holding a workpiece, and based on the detection result of the force sensor, the movement of the movable support can be automatically adjusted according to the magnitude of the force applied to the movable support when gripping and holding a workpiece. Therefore, since the movement of the movable support can be automatically adjusted based on the detection result of the force sensor, the force applied to the workpiece can be easily adjusted without performing adjustment work to adjust the amount of movement of the movable support. As a result, the force applied to the workpiece can be easily adjusted when gripping and holding a workpiece.

[0008] According to this disclosure, as described above, it is possible to provide a substrate transfer robot that can easily adjust the force applied to a workpiece when the workpiece is held in place by clamping it.

[0009] This is a schematic perspective view of a substrate transport robot according to one embodiment of the present disclosure. This is a block diagram showing the configuration of the substrate transport robot. This is a top view for explaining the configuration of the hand. This is a schematic perspective view for explaining the force sensor. This is a diagram showing an example of the temporal change in detection results and movement speed. This is a top view showing the state at the time when the movement of the movable support part begins. This is a top view showing the state at the time when the movable support part comes into contact with the workpiece. This is a top view showing the state at the time when the fixed support part and the movable support part come into contact with the workpiece. This is a flowchart diagram for explaining the control process of the workpiece transport method by the substrate transport robot.

[0010] The embodiments of this disclosure will be described below with reference to the drawings.

[0011] The configuration of a substrate transport robot 100 according to one embodiment of the present disclosure will be described with reference to Figures 1 to 8.

[0012] (Configuration of the substrate transport robot) As shown in Figure 1, the substrate transport robot 100 according to this embodiment transports a workpiece W. In this embodiment, the workpiece W is a disc-shaped substrate. The workpiece W is, for example, a glass substrate or a silicon substrate. Here, "disc-shaped" is a broad concept that also includes shapes deformed from a circle. That is, a "disc-shaped" substrate includes a substrate provided with a notch or orientation flat that serves as a position reference. Also, "disc-shaped" includes not only perfect circles but also ellipses. In a processing system that performs processing such as heating on the workpiece W, the substrate transport robot 100 transports the workpiece W to the mounting section on which the workpiece W is placed. Here, "transport" includes at least one of loading the workpiece W into the mounting section and unloading the workpiece W from the mounting section.

[0013] The substrate transport robot 100 comprises a robot arm 10 and a hand 30. The hand 30 is positioned at the tip of the robot arm 10. The robot arm 10 is supported by a base 13 and moves the hand 30 by rotating and extending relative to the base 13 through the driving of multiple joints. The robot arm 10 is also operated by control processing by the control unit 71 shown in Figure 2. The substrate transport robot 100 is a horizontal multi-joint robot that, for example, loads and unloads workpieces W, which are substrates. That is, in this embodiment, the substrate transport robot 100 is equipped with a horizontal multi-joint robot arm 10 as a moving mechanism for moving the hand 30 that holds the workpiece W. The robot arm 10 has a base link 11 and an end link 12 that are connected to each other and rotate in the horizontal plane. The base link 11 and the end link 12 rotate relative to each other in the horizontal plane with the vertical Z direction as the axis of rotation. The base end of the base link 11 of the robot arm 10 is rotatably attached to the base 13. Furthermore, the base end of the tip link 12 is rotatably attached to the tip end of the base link 11. The hand 30 is also rotatably attached to the tip end of the tip link 12. Here, "horizontal" means parallel to the mounting surface on which the substrate transport robot 100 is installed. If the substrate transport robot 100 is placed on an inclined surface or a wall, the robot arm 10 rotates in a plane parallel to the mounting surface, which is different from the horizontal plane relative to gravity.

[0014] A servo motor is positioned as a drive source for the robot arm 10. In the substrate transport robot 100, for example, a separate servo motor is positioned as a drive source for each joint of the robot arm 10. The servo motors as drive sources may be positioned inside the robot arm 10 or inside the base unit 13. An encoder is positioned for each servo motor positioned at each joint to acquire the rotational speed of the servo motor. The base unit 13 also has a lifting mechanism that moves the robot arm 10 separately in the vertical Z direction. This lifting mechanism has, for example, a servo motor as a drive source.

[0015] The hand 30 holds a plate-shaped workpiece W, which is a substrate. The hand 30 includes a blade member 31 and a hand base portion 32. Specifically, in the hand 30, one disc-shaped workpiece W is placed on the blade member 31, which is a thin plate-shaped support plate. The blade member 31 also has a mounting surface 31a on the Z1 direction side, which is the upper side in the vertical direction, on which the workpiece W is placed. The blade member 31 has a U-shape with a bifurcated tip and supports the back surface of the disc-shaped workpiece W from the Z2 direction side, which is the lower side in the vertical direction. The blade member 31 is also positioned on the hand base portion 32. That is, the base end of the blade member 31 is connected to the hand base portion 32. The hand base portion 32 is attached to the robot arm 10 and rotates along the horizontal plane relative to the robot arm 10.

[0016] <Details of the hand> As shown in Figure 2, the hand 30 includes a fixed support section 33, a fixed support section 34, a movable support section 35, a drive section 36, and a force sensor 50. In the substrate transfer robot 100, the workpiece W held by the hand 30 is fixed to the hand 30 by the fixed support section 33, the fixed support section 34, and the movable support section 35. In other words, the hand 30 is an active type substrate holding hand that holds the workpiece W in a fixed state, and is a so-called edge-grip type substrate holding hand.

[0017] As shown in Figure 3, the fixed support portion 33 and the fixed support portion 34 are each positioned on the hand 30. Specifically, the fixed support portion 33 and the fixed support portion 34 are positioned on the mounting surface 31a of the blade member 31. The fixed support portion 33 and the fixed support portion 34 are each positioned at the tip of the bifurcated blade member 31. The fixed support portion 33 and the fixed support portion 34 each abut against the workpiece W held by the hand 30. The fixed support portion 33 and the fixed support portion 34 are claw-shaped members that engage with the workpiece W placed on the mounting surface 31a of the blade member 31.

[0018] The movable support portion 35 is positioned on the hand 30 separately from the fixed support portions 33 and 34. The movable support portion 35 moves within the hand 30 to grip and hold the workpiece W together with the fixed support portions 33 and 34. The movable support portion 35 is a rod-shaped member that moves along the X direction in Figure 3, which is the front-rear direction, within the hand 30. That is, the front-rear direction is the direction of movement in which the movable support portion 35 moves within the hand 30, and is the direction from the base end to the tip of the hand 30. The rod-shaped movable support portion 35 extends along the front-rear direction, which is the direction of movement. The rod-shaped movable support portion 35 has a contact portion at its tip that contacts the workpiece W. The shape of the tip portion of the movable support portion 35 may be a surface perpendicular to the direction in which the movable support portion 35 extends, an inclined surface, or a rounded surface. The shape of the tip portion of the movable support portion 35 may also be claw-shaped to engage with the workpiece W. The tip of the movable support portion 35 may be made of the same material as the rod-shaped portion, or an elastic material such as rubber may be placed at the tip.

[0019] The movable support portion 35 moves along the X direction, which is the front-rear direction, and contacts the workpiece W held by the hand 30. Specifically, the movable support portion 35 is positioned from the inside to the outside of the hand base portion 32. The movable support portion 35 extends along the front-rear direction, which is the direction from the base end to the tip of the hand 30, along the mounting surface 31a of the blade member 31. That is, the base end of the movable support portion 35 is positioned inside the hand base portion 32 of the hand 30, and it extends in the X direction along the mounting surface 31a on the Z1 direction side of the blade member 31 toward the tip. The movable support portion 35 also contacts the peripheral edge of the disc-shaped workpiece W at its tip. In the hand 30, the movable support portion 35 moves toward the tip of the hand 30 by the operation of the drive unit 36, and together with the fixed support portion 33 and fixed support portion 34 positioned on the blade member 31, it contacts the peripheral edge of the disc-shaped workpiece W. The fixed support parts 33 and 34 and the movable support part 35 then contact the peripheral edge of the workpiece W, thereby holding the workpiece W, which is placed on the blade member 31, by sandwiching it between them. The workpiece W is held in a fixed position relative to the hand 30 by being sandwiched between the movable support part 35 and the fixed support parts 33 and 34 in the XY plane.

[0020] The drive unit 36 ​​moves the movable support unit 35. The drive unit 36 ​​moves the movable support unit 35 along the X direction, which is the front-rear direction from the base end to the tip of the hand 30. The drive unit 36 ​​has a motor 36a, a driver 36b, and a linear movement mechanism 36c. The motor 36a is the drive source for moving the movable support unit 35. In this embodiment, the motor 36a is a stepping motor. The motor 36a rotates in accordance with the pulse signal output by the control unit 71 shown in Figure 2. The driver 36b generates a current signal to rotate the motor 36a in accordance with the pulse signal from the control unit 71. The driver 36b may be located in the control unit 71. The driver 36b generates a current signal to rotate the motor 36a by a predetermined rotation angle in accordance with the pulse signal input from the control unit 71, and outputs the generated current signal to the motor 36a. The motor 36a rotates by the rotation angle corresponding to the pulse signal from the control unit 71 due to the current signal from the driver 36b. The linear movement mechanism 36c converts the rotational motion of the motor 36a into linear motion, thereby moving the movable support part 35 linearly along the X direction, which is the front-rear direction, on the hand 30. For example, the linear movement mechanism 36c may have a ball screw mechanism or a rack and pinion mechanism.

[0021] The force sensor 50 detects the force applied to the movable support portion 35. The force sensor 50 detects the force applied to the movable support portion 35 when the movable support portion 35 comes into contact with the workpiece W held by the hand 30. The force sensor 50 is located on the rod-shaped movable support portion 35. Specifically, the force sensor 50 is located inside the hand base portion 32 of the rod-shaped movable support portion 35. The force sensor 50 moves integrally with the movable support portion 35, which moves due to the operation of the drive unit 36, along the X direction.

[0022] As shown in Figure 4, the force sensor 50 includes a multi-axis force sensor that detects forces in multiple axial directions, including the X direction, which is the direction of movement of the movable support part 35. Specifically, the force sensor 50 is a six-axis force sensor that detects forces in six axial directions, including forces in three mutually orthogonal axial directions, including the X, Y, and Z directions, and three moments around the X, Y, and Z directions. The force sensor 50 outputs the detection results for each of the six axial directions to the control unit 71. The force sensor 50 is a small sensor configured, for example, by MEMS (Micro Electro Mechanical Systems).

[0023] As shown in Figure 2, the substrate transport robot 100 includes a control unit 71 and a storage unit 72. The control unit 71 is a computer having an arithmetic unit such as a CPU (Central Processing Unit). The storage unit 72 includes a storage device including flash memory such as an SSD (Solid State Drive). The control unit 71 may be positioned at a distance from the substrate transport robot 100, or it may be positioned integrally with the substrate transport robot 100. The control unit 71 is a robot controller that controls the operation of each part of the substrate transport robot 100 based on programs and parameters stored in the storage unit 72.

[0024] The control unit 71 controls the transport operation for transporting the workpiece W. The control unit 71 includes, for example, a main control unit that controls the operation of each joint of the robot arm 10, a servo control unit that controls the drive current output to the servo motors, which are drive sources, located at each joint of the robot arm 10 based on commands from the main control unit, and a drive circuit unit that supplies power to each joint of the robot arm 10. In the control unit 71, for example, the main control unit and the servo control unit each have a separate computing device such as a CPU. The control unit 71 controls the operation of the robot arm 10 by feedback control by controlling the operation of the servo motors, which are drive sources, based on the output from the encoder for each joint of the robot arm 10. The control unit 71 controls the transport operation of the workpiece W based on, for example, a control signal from a higher-level control device that controls a processing system that performs machining on the workpiece W.

[0025] (Workpiece Holding Control) The control unit 71 also controls the movement of the movable support unit 35 by the drive unit 36 ​​by controlling the operation of the drive unit 36. In this embodiment, when holding the workpiece W, the control unit 71 controls the operation of the robot arm 10 so that the workpiece W is placed on the blade member 31 of the hand 30, and moves the movable support unit 35 by controlling the operation of the drive unit 36 ​​while the workpiece W is placed on the blade member 31. In this embodiment, when holding the workpiece W, the control unit 71 acquires a signal indicating the detection result from the force sensor 50. Then, the control unit 71 controls the movement of the movable support unit 35 by the drive unit 36 ​​based on the detection result of the force sensor 50. Specifically, the control unit 71 generates a pulse signal to control the operation of the motor 36a based on the detection result of the force sensor 50. The control unit 71 controls the movement of the movable support unit 35 by the operation of the motor 36a by controlling the pulse signal generated based on the detection result of the force sensor 50. In other words, in this embodiment, the control unit 71 does not detect the rotation angle of the motor 36a using an encoder or the like, nor does it detect the position of the movable support unit 35 using a position sensor or the like. Instead, it controls the movement of the movable support unit 35 by controlling the operation of the motor 36a based on the detection result of the force sensor 50.

[0026] The control unit 71 controls the movement of the movable support unit 35 by the drive unit 36 ​​based on the force detection result in the X direction, which is the direction of movement, by the force sensor 50. That is, the control unit 71 controls the movement of the rod-shaped movable support unit 35 that contacts the peripheral edge of the plate-shaped workpiece W by controlling the operation of the motor 36a based on the force detection result in the X direction of the force sensor 50. In this embodiment, the control unit 71 controls the movement of the movable support unit 35 based on the detection result of the force sensor 50, thereby adjusting the force applied to the workpiece W and holding the workpiece W between the movable support unit 35, the fixed support unit 33, and the fixed support unit 34. Specifically, the control unit 71 controls the movement of the movable support unit 35 to mitigate the impact applied to the workpiece W based on the detection result of the force sensor 50. The control unit 71 stops the movement of the movable support unit 35 when it detects that the workpiece W is being held between the movable support unit 35, the fixed support unit 33, and the fixed support unit 34 based on the detection result of the force sensor 50.

[0027] As shown in Figure 5, in this embodiment, the control unit 71 changes the movement speed of the movable support unit 35 for holding the workpiece W in stages by controlling the operation of the movable support unit 35 in stages based on the detection result of the force sensor 50. For example, when the movable support unit 35 is moved, the control unit 71 detects in stages, based on the detection result of the force sensor 50, that the movable support unit 35 has come into contact with the workpiece W and that the workpiece W is being held by being sandwiched between the movable support unit 35, the fixed support unit 33, and the fixed support unit 34. Based on the detection result of the force sensor 50, the control unit 71 reduces the movement speed of the movable support unit 35 when it is detected that the movable support unit 35 has come into contact with the workpiece W. Then, based on the detection result of the force sensor 50, the control unit 71 stops the movement of the movable support unit 35 when it is detected that the workpiece W is being held by being sandwiched between the movable support unit 35, the fixed support unit 33, and the fixed support unit 34. The control unit 71 controls the movement of the movable support unit 35 in steps based on threshold values ​​D1 and D2 that have been set in advance and stored in the memory unit 72.

[0028] First, before the movable support unit 35 starts moving, the control unit 71 controls the movement of the robot arm 10 to place the workpiece W on the blade member 31 of the hand 30 in order to hold the workpiece W in the hand 30. Then, for example, at timing T0, the movement of the movable support unit 35 is started in order to grip and hold the workpiece W that is placed on the blade member 31. In the example in Figure 5, at timing T0, the movement speed of the movable support unit 35 increases from 0 to V1.

[0029] For example, as shown in Figure 6, at timing T0, the workpiece W is placed on the blade member 31 but is not in contact with any of the fixed support portion 33, fixed support portion 34, or movable support portion 35. In this state, the control unit 71 starts moving the movable support portion 35 toward the X1 direction, which is the direction of movement. Since the workpiece W is not in contact with the movable support portion 35, the magnitude of the force detected by the force sensor 50 at timing T0 is 0 or a very small value.

[0030] As shown in Figure 5, the control unit 71 moves the movable support unit 35 at a relatively large pre-set speed V1 until contact between the movable support unit 35 and the workpiece W is detected. Specifically, from timing T0 onward, when the movement of the movable support unit 35 begins, if the detection result from the force sensor 50 is less than the threshold D1, the control unit 71 assumes that the movable support unit 35 and the workpiece W are not in contact with each other and moves the movable support unit 35 at a relatively large speed V1. The control unit 71 then determines that the movable support unit 35 has come into contact with the workpiece W when the detection result from the force sensor 50 exceeds the threshold D1. In the example in Figure 5, at timing T1, the movable support unit 35 comes into contact with the workpiece W, and the detection result from the force sensor 50 is greater than the threshold D1.

[0031] As shown in Figure 7, at timing T1, the movable support 35 is in contact with the workpiece W, while the workpiece W is not in contact with the fixed support 33 and fixed support 34. In this case, the control unit 71 determines that the workpiece W has not been held and reduces the movement speed while continuing to move the movable support 35. As the movement of the movable support 35 continues, the workpiece W moves toward the fixed support 33 and fixed support 34 while in contact with the movable support 35. For example, as shown in Figure 5, if the detection result from the force sensor 50 is greater than threshold D1 and less than or equal to threshold D2, the control unit 71 changes to a relatively small movement speed V2 and moves the movable support 35 until the workpiece W comes into contact with the fixed support 33 and fixed support 34.

[0032] The control unit 71 then determines that the fixed support units 33 and 34 have come into contact with the workpiece W and that the workpiece W has been held in place, when the detection result from the force sensor 50 exceeds the threshold D2. In the example in Figure 5, at timing T2, the detection result from the force sensor 50 is greater than the threshold D2 because the fixed support units 33 and 34 come into contact with the workpiece W. As shown in Figure 8, at timing T2, the workpiece W is held in a fixed state relative to the hand 30 by coming into contact with the fixed support units 33, 34 and 35. In this case, the control unit 71 determines that the workpiece W has been held in place and stops the movement of the movable support unit 35. For example, as shown in Figure 5, the control unit 71 stops the movement of the movable support unit 35 when the detection result from the force sensor 50 is greater than the threshold D2.

[0033] <Determination of Abnormal Holding State> In this embodiment, the control unit 71 controls the movement of the movable support unit 35 by the drive unit 36 ​​based on the force detection result in the direction of movement by the force sensor 50, and determines an abnormality in the holding state of the workpiece W by the hand 30 based on the force detection result in an axial direction different from the direction of movement by the force sensor 50. When holding the workpiece W, if the position of the workpiece W is misaligned with the hand 30, when the movable support unit 35 is moved, a force in a direction different from the X direction, which is the direction of movement, is applied to the movable support unit 35. Therefore, the control unit 71 determines that the workpiece W is not being held properly and determines an abnormality in the holding state of the workpiece W if, for example, the force detection result in an axial direction different from the X direction by the force sensor 50 exceeds a predetermined determination threshold. That is, the control unit 71 determines that an abnormality in the holding state of the workpiece W has been detected if any of the force detection results in the Y and Z directions detected by the six-axis force sensor 50, and the moment detection results around the X direction, Y direction, and Z direction are greater than a predetermined determination threshold that has been set in advance. For example, if the control unit 71 determines that there is an abnormality in the holding state of the workpiece W, it outputs error information indicating the abnormality in the holding state of the workpiece W.

[0034] The control unit 71 may also determine an abnormality in the holding state of the workpiece W based on the force detection result in the direction of movement by the force sensor 50. For example, if the control unit 71 moves the movable support unit 35 a certain distance and the detection result by the force sensor 50 does not exceed a predetermined threshold D1, the control unit 71 determines that the workpiece W is not placed on the blade member 31 and is not properly held by the hand 30, and that there is an abnormality in the placement of the workpiece W. For example, if a predetermined time has elapsed since the start of movement of the movable support unit 35 and the detection result by the force sensor 50 remains below the threshold D1, the control unit 71 determines that the workpiece W is not properly placed on the blade member 31, and that there is an abnormality in the placement of the workpiece W.

[0035] (Control Processing for Workpiece Transport Method) Next, with reference to Figure 9, the control processing for the workpiece transport method by the substrate transport robot 100 will be described. The control processing from step S1 to step S9 in this workpiece transport method is performed by the control unit 71.

[0036] First, in step S1, the workpiece W is placed on the blade member 31 of the hand 30. The control unit 71 controls the movement of the robot arm 10 and the hand 30 so that the workpiece W is placed on the blade member 31 of the hand 30. For example, the control unit 71 controls the movement of the robot arm 10 and the hand 30 based on a preset amount of movement. The preset amount of movement is stored in the storage unit 72.

[0037] Next, in step S2, the movement of the movable support part 35 is initiated. The control unit 71 controls the operation of the drive unit 36 ​​to move the movable support part 35 toward the workpiece W placed on the blade member 31 at a relatively high speed V1.

[0038] Next, in step S3, it is determined whether or not contact has been detected between the movable support 35 and the workpiece W. If it is determined that contact has been detected between the movable support 35 and the workpiece W, the process proceeds to step S4. If it is determined that contact has not been detected between the movable support 35 and the workpiece W, the control process is put into standby mode. The control unit 71 determines that contact has been detected between the movable support 35 and the workpiece W if the force detection result in the X direction by the force sensor 50 is greater than the threshold D1. In step S3, if the movable support 35 has moved a predetermined distance but no force is detected in the X direction, it may be determined that there is a workpiece W placement abnormality, as the workpiece W is not placed on the blade member 31. In that case, error information indicating a workpiece W placement abnormality may be output, similar to the error information indicating an abnormal holding state in step S9, which will be described later.

[0039] In step S4, the movement speed of the movable support 35 is reduced. The control unit 71 reduces the movement speed of the movable support 35 from a relatively high speed V1 to a relatively low speed V2 when the force detection result in the X direction by the force sensor 50 is greater than a predetermined threshold D1.

[0040] Next, in step S5, it is determined whether or not the holding of the workpiece W has been completed. If it is determined that the holding of the workpiece W has been completed, the process proceeds to step S6. If it is determined that the holding of the workpiece W has not been completed, the control process is put into standby mode. The control unit 71 determines that the holding of the workpiece W has been completed when the force detection result in the X direction by the force sensor 50 is greater than the threshold D2. That is, the control unit 71 continues to move the movable support part 35 at the speed V2 changed in step S4 until the force detection result in the X direction by the force sensor 50 is greater than the threshold D2, and determines that the holding of the workpiece W has been completed when the force detection result in the X direction by the force sensor 50 is greater than the threshold D2.

[0041] In step S6, the workpiece W is held in place by the hand 30, being sandwiched between the movable support 35, the fixed support 33, and the fixed support 34. As this completes the holding of the workpiece W, the movement of the movable support 35 is stopped. The control unit 71 stops the movement of the movable support 35 by stopping the operation of the drive unit 36 ​​when the detection result of the force sensor 50 in the X direction is greater than the threshold D2.

[0042] Next, in step S7, it is determined whether or not the holding state of the workpiece W is abnormal. If it is determined that the holding state of the workpiece W is abnormal, the process proceeds to step S9. If it is determined that the holding state of the workpiece W is not abnormal, the process proceeds to step S8. When the control unit 71 detects contact between the movable support part 35 and the workpiece W, it determines whether or not the holding state of the workpiece W is abnormal based on the force detection result in an axial direction other than the X direction by the force sensor 50. The control unit 71 determines that the holding state of the workpiece W is abnormal if the force detection result in an axial direction other than the X direction by the force sensor 50 is greater than a predetermined determination threshold.

[0043] In step S8, the workpiece W is transported. The control unit 71, assuming that the hand 30 has successfully held the workpiece W, controls the operation of the robot arm 10 and the hand 30 to move the workpiece W to a preset destination placement position. Then, with the workpiece W at the destination placement position, the control unit 71 releases the hold on the workpiece W by moving the movable support 35 away from the workpiece W using the operation of the drive unit 36. As a result, the control unit 71 places the workpiece W at the destination placement position. After stopping the movement of the movable support 35 in step S6, the control unit 71 holds the movable support 35 in contact with the workpiece W during the period until the movable support 35 is moved away from the workpiece W at the destination placement position. For example, the control unit 71 generates a holding torque by supplying power to the motor 36a of the drive unit 36, and holds the movable support 35 in a stopped state by maintaining the rotation of the motor 36a.

[0044] In step S9, an error is output if an abnormality in the holding state of the workpiece W is detected. The error information is output, for example, to a higher-level control device in the processing system that performs machining on the workpiece W. In the processing system, for example, information indicating that error information has been acquired is displayed on a display device. If error information is output in step S9, the transport operation of the workpiece W is stopped, and the control processing of the workpiece transport method is terminated.

[0045] (Effect of the Embodiment) In this embodiment, the following effects can be obtained.

[0046] In this embodiment, as described above, the substrate transfer robot 100 includes a force sensor 50 that detects a force applied to the movable support portion 35, and a control unit 71 that controls the movement of the movable support portion 35 by the drive unit 36 based on the detection result of the force sensor 50. Thereby, since the magnitude of the force applied to the movable support portion 35 when sandwiching and holding the workpiece W can be detected by the force sensor 50, based on the detection result by the force sensor 50, the magnitude of the force applied to the movable support portion 35 when sandwiching and holding the workpiece W can be detected. Accordingly, the movement of the movable support portion 35 can be automatically adjusted according to the magnitude of the force applied to the movable support portion 35. Therefore, since the movement of the movable support portion 35 can be automatically adjusted based on the detection result by the force sensor 50, the force applied to the workpiece W can be easily adjusted without performing an adjustment operation for adjusting the movement amount of the movable support portion 35. As a result, when sandwiching and holding the workpiece W, the force applied to the workpiece W can be easily adjusted.

[0047] The drive unit 36 includes a motor 36a. The control unit 71 controls the movement of the movable support portion 35 by controlling the operation of the motor 36a based on the detection result of the force sensor 50. Thereby, compared with the case where the movable support portion 35 is moved by an actuator such as an air cylinder, the movement of the movable support portion 35 can be more easily adjusted by controlling the rotation of the motor 36a. Therefore, by moving the movable support portion 35 by the motor 36a, the force applied to the workpiece W when sandwiching and holding the workpiece W can be more easily adjusted.

[0048] The hand 30 includes a blade member 31 on which a plate-shaped workpiece W is placed. The fixed support portions 33 and 34 are disposed on the placement surface 31a of the blade member 31 on which the workpiece W is placed. The movable support portion 35 abuts against the peripheral edge portion of the plate-shaped workpiece W together with the fixed support portions 33 and 34 disposed on the blade member 31 by the operation of the drive portion 36. The control unit 71 controls the movement of the movable support portion 35 based on the detection result of the force sensor 50. Thereby, when the plate-shaped workpiece W is sandwiched and held by the fixed support portions 33 and 34 and the movable support portion 35, the force applied to the workpiece W can be easily adjusted without performing an adjustment operation for adjusting the movement amount of the movable support portion 35 that abuts against the peripheral edge portion of the plate-shaped workpiece W. As a result, even when the movable support portion 35 is brought into contact with and held against the peripheral edge portion of the plate-shaped workpiece W, the force applied to the workpiece W can be easily adjusted.

[0049] The control unit 71 moves the movable support portion 35 by controlling the operation of the drive portion 36 when holding the workpiece W. Then, when it is detected based on the detection result of the force sensor 50 that the workpiece W is sandwiched and held by the movable support portion 35 and the fixed support portions 33 and 34, the control unit 71 stops the movement of the movable support portion 35. Thereby, when it is detected based on the detection result of the force sensor 50 that the holding of the workpiece W by the fixed support portions 33 and 34 and the movable support portion 35 is completed, the movement of the movable support portion 35 can be automatically stopped. Therefore, it is possible to effectively suppress the force being applied to the workpiece W by the movable support portion 35 more than necessary without performing an operation for adjusting the movement of the movable support portion 35, so that the force applied to the workpiece W can be effectively and easily adjusted.

[0050] When the movable support portion 35 is moved, the control unit 71 detects in stages, based on the detection results of the force sensor 50, that the movable support portion 35 has come into contact with the workpiece W and that the workpiece W is being held between the movable support portion 35 and the fixed support portions 33 and 34. This allows for more detailed adjustment of the movement of the movable support portion 35 according to the contact state of the movable support portion 35 with the workpiece W when moving the movable support portion 35 to hold the workpiece W, by detecting in stages that the movable support portion 35 has come into contact with the workpiece W and that the workpiece W is being held between them. Therefore, the force applied to the workpiece W by the movement of the movable support portion 35 can be adjusted more effectively and easily.

[0051] Based on the detection results of the force sensor 50, the control unit 71 reduces the movement speed of the movable support unit 35 when it detects that the movable support unit 35 has come into contact with the workpiece W, and stops the movement of the movable support unit 35 when it detects that the workpiece W is being held between the movable support unit 35 and the fixed support units 33 and 34. As a result, the movement speed of the movable support unit 35 can be kept relatively high until it comes into contact with the workpiece W, effectively shortening the time required for the movable support unit 35 to hold the workpiece W. Furthermore, after the movable support unit 35 comes into contact with the workpiece W, the movement speed of the movable support unit 35 can be kept relatively low until holding is complete, so the force applied to the workpiece W can be effectively adjusted to prevent the force applied to the workpiece W by the movable support unit 35 from becoming too large when holding is complete. As a result, the time required for the transport operation of the workpiece W can be effectively shortened, and the force applied to the workpiece W can be effectively adjusted.

[0052] The movable support portion 35 is positioned on the hand 30 and, by moving in the front-rear direction on the hand 30, clamps and holds the workpiece W held by the hand 30 together with the fixed support portions 33 and 34. The drive unit 36 ​​includes a linear movement mechanism 36c that moves the movable support portion 35 in the front-rear direction on the hand 30. This allows the movable support portion 35 to be easily moved in the front-rear direction by the linear movement mechanism 36c. Therefore, when the movable support portion 35 is moved in the front-rear direction to hold the workpiece W, the force applied to the workpiece W can be easily adjusted.

[0053] The movable support portion 35 is rod-shaped and extends along the front-rear direction. The force sensor 50 is positioned on the rod-shaped movable support portion 35 and detects the force applied to the movable support portion 35 when the movable support portion 35 comes into contact with the workpiece W held by the hand 30. As a result, when the workpiece W is held by being gripped by the rod-shaped movable support portion 35, the force sensor 50 is positioned on the rod-shaped movable support portion 35, so the force applied to the movable support portion 35 can be detected with high accuracy. Consequently, when the workpiece W is held by being gripped by the rod-shaped movable support portion 35, the force applied to the workpiece W can be easily and accurately adjusted.

[0054] The hand 30 includes a blade member 31 on which a plate-shaped workpiece W is placed, and a hand base portion 32 on which the blade member 31 is positioned. The movable support portion 35 is rod-shaped and extends in the front-rear direction along the blade member 31 from the inside to the outside of the hand base portion 32. The force sensor 50 is positioned in the rod-shaped movable support portion 35 in the part inside the hand base portion 32. As a result, since the force sensor 50 is positioned inside the hand base portion 32, wiring members connected to the force sensor 50 can be positioned more easily compared to when the force sensor 50 is positioned outside the hand base portion 32.

[0055] The force sensor 50 includes a multi-axis force sensor that detects forces in multiple axial directions, including the direction of movement of the movable support part 35. The control unit 71 controls the movement of the movable support part 35 by the drive unit 36 ​​based on the force detection results in the direction of movement by the force sensor 50 as a multi-axis force sensor. The control unit 71 then determines an abnormality in the holding state of the workpiece W by the hand 30 based on the force detection results in axial directions different from the direction of movement by the force sensor 50. As a result, the force applied to the workpiece W can be easily adjusted by the multi-axis force sensor 50 that detects forces in multiple axial directions, and abnormalities in the holding state of the workpiece W by the hand 30 can also be determined. As a result, the complexity of the device configuration can be suppressed compared to the case where a sensor for determining abnormalities in the holding state of the workpiece W is arranged separately from the force sensor 50.

[0056] If the control unit 71 determines that there is an abnormality in the holding state of the workpiece W, it outputs error information indicating that an abnormality in the holding state of the workpiece W has been determined. This makes it easy to recognize that an abnormality has occurred in the holding state of the workpiece W by recognizing the outputted error information.

[0057] The control unit 71 controls the movement of the movable support unit 35 by controlling the operation of the motor 36a based on the detection result of the force sensor 50, without detecting the rotation of the motor 36a. As a result, the movement of the movable support unit 35 can be controlled by controlling the operation of the motor 36a based on the detection result of the force sensor 50, without requiring a configuration to detect the rotation of the motor 36a, such as an encoder, thus suppressing the complexity of the device configuration.

[0058] The drive unit 36 ​​includes a stepping motor 36a that rotates in response to a pulse signal. The control unit 71 controls the movement of the movable support unit 35 by the operation of the stepping motor 36a by controlling the pulse signal based on the detection result of the force sensor 50. As a result, the movement of the movable support unit 35 by the operation of the stepping motor can be controlled by controlling the pulse signal based on the detection result of the force sensor 50, so the movement of the movable support unit 35 can be controlled without the need to include a configuration to detect the rotation of the motor 36a, such as an encoder. Therefore, the complexity of the device configuration can be suppressed. In addition, compared to controlling the rotation of the motor 36a by feedback control using an encoder, controlling the operation of the motor 36a, which is a stepping motor, based on the detection result of the force sensor 50 reduces the processing load of the control process. Therefore, the responsiveness of the control can be improved in the operation of the motor 36a, so the force applied to the workpiece W can be adjusted more easily.

[0059] The control unit 71 controls the movement of the movable support unit 35 based on the detection results from the force sensor 50, thereby adjusting the force applied to the workpiece W and holding the workpiece W between the movable support unit 35 and the fixed support units 33 and 34. This allows for automatic control of the movement of the movable support unit 35 while adjusting the force applied to the workpiece W based on the detection results from the force sensor 50 when holding the workpiece W between the movable support unit 35 and the fixed support units 33 and 34. Therefore, it is easy to prevent the force applied to the workpiece W from becoming unnecessarily large when holding the workpiece W.

[0060] [Variations] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of this disclosure is indicated by the claims rather than the description of the embodiments above, and further includes all modifications (variations) in the meaning and scope equivalent to the claims.

[0061] For example, in the above embodiment, an example was shown in which the hand 30 holding the workpiece W is moved by a horizontally articulated robot arm 10, but the present disclosure is not limited thereto. In this disclosure, the moving mechanism for moving the hand may be a vertically articulated robot arm, or a robot arm with a parallel link mechanism. It may also be a robot arm with a Cartesian coordinate system, a cylindrical coordinate system, or a polar coordinate system. That is, the hand may be moved not only by a link mechanism, but also by a moving mechanism having a linear movement mechanism.

[0062] Furthermore, although the above embodiment shows an example in which the substrate transfer robot 100 is equipped with one hand 30 that holds one workpiece W, the present disclosure is not limited thereto. In the present disclosure, the substrate transfer robot may be configured to hold multiple workpieces. For example, multiple hands may be arranged on one robot arm as a moving mechanism, or multiple robot arms, each with a hand attached, may be arranged to hold multiple workpieces. In that case, each of the multiple workpieces may be held by being sandwiched between a movable support and a fixed support, or only some of the multiple workpieces may be held by being sandwiched between a movable support and a fixed support.

[0063] Furthermore, although the above embodiment shows an example in which a workpiece W, which is a disc-shaped substrate, is held by the hand 30, the present disclosure is not limited thereto. In this disclosure, the workpiece held by the hand may not be the substrate itself, but a jig for processing the substrate. The jig for processing the substrate may be, for example, a jig on which the substrate is fixed in order to hold the substrate, or a jig that mimics a substrate used for teaching transport operations, etc. Also, the workpiece held by the hand may not be circular, but a polygonal substrate or jig such as a rectangle.

[0064] Furthermore, although the above embodiment shows an example in which a bifurcated plate-shaped blade member 31 is arranged on the hand 30, the present disclosure is not limited to this. In the present disclosure, the blade member of the hand does not have to be bifurcated. The blade member may be a rectangular plate. Also, the blade member may be branched into three or more parts.

[0065] Furthermore, in the above embodiment, an example was shown in which the workpiece W is held by being sandwiched between the movable support portion 35 and a pair of fixed support portions 33 and 34 by bringing the rod-shaped movable support portion 35 into contact with the workpiece W. However, the present disclosure is not limited to this. In the present disclosure, the tip portion of the movable support portion 35 may be bifurcated or divided into multiple portions. That is, the movable support portion may be arranged to contact the workpiece W at multiple positions spaced apart from each other. Also, there may be only one fixed support portion, or there may be three or more fixed support portions.

[0066] Furthermore, while the above embodiment shows an example in which the movement of the movable support portion 35 is stopped when it is detected that the workpiece W is being held between the movable support portion 35 and the fixed support portions 33 and 34, the present disclosure is not limited thereto. In this disclosure, the movement of the movable support portion may be stopped based on the detection result of the force sensor, regardless of whether or not the workpiece is being held between the movable support portion and the fixed support portion.

[0067] Furthermore, in the above embodiment, based on the detection result of the force sensor 50, an example was shown in which the movement speed of the movable support 35 is reduced when it is detected that the movable support 35 has come into contact with the workpiece W, and when it is detected that the workpiece W has been held between the movable support 35 and the fixed support 33 and 34, thereby controlling the movement of the movable support 35. However, the disclosure is not limited to this. In this disclosure, it is also possible not to detect in stages that the movable support 35 has come into contact with the workpiece and that the workpiece has been held between the movable support 35 and the fixed support 33 and 34. For example, the movement of the movable support 35 may be controlled by detecting that the workpiece has been held between the movable support 35 and the fixed support 33 and 34, based on the detection result of the force sensor, without detecting that the movable support 35 has come into contact with the workpiece. In that case, one threshold value may be set in advance, and the movement of the movable support may be stopped when the detection result of the force sensor exceeds the set threshold value. Alternatively, the movement speed of the movable support may be changed regardless of the detection result of the force sensor. For example, the movement speed may be automatically reduced after a predetermined period of time has elapsed since the start of movement of the movable support, and the movement may be stopped based on the detection result of the force sensor.

[0068] Furthermore, although the above embodiment shows an example in which the movable support portion 35 moves linearly in the front-rear direction in the hand 30, the present disclosure is not limited thereto. In this disclosure, the movable support portion may be moved in an arc.

[0069] Furthermore, in the above embodiment, an example was shown in which the force sensor 50 is located in the internal part of the hand base portion 32, on a rod-shaped movable support portion 35 that extends from the inside to the outside of the hand base portion 32. However, the present disclosure is not limited to this. In this disclosure, the force sensor may be located outside the hand base portion. For example, the force sensor may be located at the tip of the movable support portion.

[0070] Furthermore, in the above embodiment, an example was shown in which the movement of the movable support 35 is controlled based on the force detection result in the direction of movement of the movable support 35 detected by the multi-axis force sensor 50, and an abnormality in the holding state of the workpiece W in the hand 30 is determined based on the force detection result in an axial direction different from the direction of movement of the force sensor 50, but the present disclosure is not limited thereto. In this disclosure, the movement of the movable support 35 may be controlled based on the detection result of the force sensor by arranging a force sensor that detects only one axis. Also, even when a multi-axis force sensor is arranged, the abnormality in the holding state of the workpiece may not be determined based on the force sensor. In addition, the force sensor may be a multi-axis force sensor other than one axis and six axes, such as a two-axis, three-axis, and four-axis force sensor. Furthermore, an abnormality in the holding state of the workpiece in the hand may be determined based on the force detection result in the direction of movement of the force sensor.

[0071] Furthermore, in the above embodiment, when an abnormality in the holding state of the workpiece W is detected, an example is shown in which error information is output and information indicating that error information has been acquired is displayed on a display device in a processing system that performs machining on the workpiece W. However, this disclosure is not limited to this. In this disclosure, the error information may be notified by voice information. Alternatively, the error information may be notified by a display device placed on a substrate transport robot or the like.

[0072] Furthermore, although the above embodiment shows an example in which the movable support portion 35 is moved by a drive unit 36 ​​including a stepping motor 36a, the present disclosure is not limited thereto. In this disclosure, the drive unit that moves the movable support portion may include an air actuator. The drive unit may also include a solenoid coil. The drive unit may also include a linear motor. The drive unit may also include a servo motor. In addition to the motor, the drive unit may have a configuration that detects the rotation of the motor, such as an encoder. In that case, the motor may be controlled by feedback control using the detected motor rotation.

[0073] Furthermore, in the above embodiment, an example was shown in which the control unit 71, which acts as a robot controller for controlling the movement of the robot arm 10, controls the movement of the drive unit 36 ​​to control the movement of the movable support unit 35, but the present disclosure is not limited to this. In the present disclosure, a control device for controlling the movement of the movable support unit may be arranged separately from the robot controller for controlling the movement of the robot arm. In that case, the control device may be arranged in the base unit, the moving mechanism for moving the hand such as the robot arm, or inside the hand in the substrate transfer robot.

[0074] The functions of the elements disclosed herein can be performed using circuits or processing circuits, including general-purpose processors, dedicated processors, integrated circuits, ASICs (Application Specific Integrated Circuits), conventional circuits, and / or combinations thereof, configured or programmed to perform the disclosed functions. A processor is considered a processing circuit or circuit because it includes transistors and other circuits. In this disclosure, a circuit, unit, or means is hardware that performs the enumerated functions, or hardware programmed to perform the enumerated functions. The hardware may be hardware disclosed herein, or other known hardware that is programmed or configured to perform the enumerated functions. If the hardware is a processor, which is considered a type of circuit, then the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and / or the processor.

[0075] [Embodiments] The exemplary embodiments described above will be understood by those skilled in the art to be specific examples of the following embodiments.

[0076] (Aspect 1) A substrate transport robot comprising: a hand for holding a workpiece including at least one of a substrate and a jig for processing the substrate; a fixed support portion disposed on the hand and in contact with the workpiece held by the hand; a movable support portion that holds the workpiece together with the fixed support portion in the hand; a drive unit for moving the movable support portion; a force sensor for detecting the force applied to the movable support portion; and a control unit that controls the movement of the movable support portion by the drive unit based on the detection result of the force sensor.

[0077] (Aspect 2) The substrate transport robot according to aspect 1, wherein the drive unit includes a motor, and the control unit controls the movement of the movable support unit by controlling the operation of the motor based on the detection result of the force sensor.

[0078] (Aspect 3) The substrate transport robot according to aspect 1 or aspect 2, wherein the hand includes a blade member on which the plate-shaped workpiece is placed, the fixed support portion is arranged on the mounting surface of the blade member on which the workpiece is placed, the movable support portion contacts the peripheral edge of the plate-shaped workpiece together with the fixed support portion arranged on the blade member by the operation of the drive unit, and the control unit controls the movement of the movable support portion that contacts the peripheral edge of the plate-shaped workpiece based on the detection result of the force sensor.

[0079] (Aspect 4) A substrate transport robot according to any one of aspects 1 to 3, wherein the control unit moves the movable support unit by controlling the operation of the drive unit when holding the workpiece, and stops the movement of the movable support unit when it is detected that the workpiece is being held between the movable support unit and the fixed support unit based on the detection result of the force sensor.

[0080] (Aspect 5) The substrate transport robot according to aspect 4, wherein the control unit, when moving the movable support, detects in steps, based on the detection result of the force sensor, that the movable support has come into contact with the workpiece and that the workpiece is being held between the movable support and the fixed support.

[0081] (Aspect 6) The substrate transport robot according to aspect 5, wherein the control unit reduces the movement speed of the movable support when it is detected that the movable support has come into contact with the workpiece, based on the detection result of the force sensor, and stops the movement of the movable support when it is detected that the workpiece is being held between the movable support and the fixed support.

[0082] (Aspect 7) The substrate transport robot according to any one of aspects 1 to 6, wherein the movable support portion is arranged in the hand and moves in the front-rear direction in the hand to grip and hold the workpiece held in the hand together with the fixed support portion, and the drive unit includes a linear movement mechanism that moves the movable support portion in the front-rear direction in the hand.

[0083] (Aspect 8) The substrate transport robot according to aspect 7, wherein the movable support portion is rod-shaped and extends along the front-rear direction, and the force sensor is arranged on the rod-shaped movable support portion to detect the force applied to the movable support portion when the movable support portion comes into contact with the workpiece held by the hand.

[0084] (Aspect 9) The substrate transport robot according to aspect 8, wherein the hand includes a blade member on which the plate-shaped workpiece is placed and a hand base portion on which the blade member is positioned, the movable support portion is rod-shaped and extends in the front-rear direction along the blade member from the inside to the outside of the hand base portion, and the force sensor is positioned in the rod-shaped movable support portion in the part inside the hand base portion.

[0085] (Aspect 10) The substrate transport robot according to any one of aspects 1 to 9, wherein the force sensor includes a multi-axis force sensor that detects forces in a plurality of axial directions including the direction of movement of the movable support, the control unit controls the movement of the movable support by the drive unit based on the force detection result in the direction of movement by the multi-axis force sensor, and determines an abnormality in the holding state of the workpiece by the hand based on the force detection result in the axial direction different from the direction of movement by the multi-axis force sensor.

[0086] (Aspect 11) The substrate transport robot according to aspect 10, wherein the control unit outputs error information indicating an abnormality in the workpiece holding state when it determines that there is an abnormality in the workpiece holding state.

[0087] (Aspect 12) The substrate transport robot according to aspect 2, wherein the control unit controls the movement of the movable support by controlling the operation of the motor based on the detection result of the force sensor without detecting the rotation of the motor.

[0088] (Aspect 13) The substrate transport robot according to aspect 2, wherein the drive unit includes a stepping motor that rotates in response to a pulse signal, and the control unit controls the movement of the movable support unit by the operation of the stepping motor by controlling the pulse signal based on the detection result of the force sensor.

[0089] (Aspect 14) The substrate transport robot according to any one of aspects 1 to 11, wherein the control unit controls the movement of the movable support based on the detection result of the force sensor, thereby adjusting the force applied to the workpiece and holding the workpiece between the movable support and the fixed support.

[0090] 10 Robot arm 30 Hand 31 Blade member 32 Hand base 33, 34 Fixed support part 35 Movable support part 36 Drive unit 36a Motor (stepping motor) 36c Linear movement mechanism 50 Force sensor (multi-axis force sensor) 71 Control unit 100 Substrate transport robot

Claims

1. A substrate transport robot comprising: a hand for holding a workpiece including at least one of a substrate and a jig for processing the substrate; a fixed support portion disposed on the hand and in contact with the workpiece held by the hand; a movable support portion that holds the workpiece together with the fixed support portion in the hand; a drive unit for moving the movable support portion; a force sensor for detecting the force applied to the movable support portion; and a control unit that controls the movement of the movable support portion by the drive unit based on the detection result of the force sensor.

2. The substrate transport robot according to claim 1, wherein the drive unit includes a motor, and the control unit controls the movement of the movable support unit by controlling the operation of the motor based on the detection result of the force sensor.

3. The substrate transport robot according to claim 1, wherein the hand includes a blade member on which the plate-shaped workpiece is placed, the fixed support portion is arranged on the mounting surface of the blade member on which the workpiece is placed, the movable support portion contacts the peripheral edge of the plate-shaped workpiece together with the fixed support portion arranged on the blade member by the operation of the drive unit, and the control unit controls the movement of the movable support portion that contacts the peripheral edge of the plate-shaped workpiece based on the detection result of the force sensor.

4. The substrate transport robot according to claim 1, wherein the control unit moves the movable support unit by controlling the operation of the drive unit when holding the workpiece, and stops the movement of the movable support unit when it is detected, based on the detection result of the force sensor, that the workpiece is being held between the movable support unit and the fixed support unit.

5. The substrate transport robot according to claim 4, wherein, when the movable support is moved, the control unit detects in steps, based on the detection result of the force sensor, that the movable support has come into contact with the workpiece and that the workpiece is being held between the movable support and the fixed support.

6. The substrate transport robot according to claim 5, wherein the control unit, based on the detection result of the force sensor, reduces the movement speed of the movable support when it is detected that the movable support has come into contact with the workpiece, and stops the movement of the movable support when it is detected that the workpiece is being held between the movable support and the fixed support.

7. The substrate transport robot according to claim 1, wherein the movable support portion is arranged in the hand and moves in the front-rear direction within the hand to clamp and hold the workpiece held by the hand together with the fixed support portion, and the drive unit includes a linear movement mechanism for moving the movable support portion in the front-rear direction within the hand.

8. The substrate transport robot according to claim 7, wherein the movable support portion is rod-shaped and extends along the front-rear direction, and the force sensor is arranged on the rod-shaped movable support portion to detect the force applied to the movable support portion when the movable support portion comes into contact with the workpiece held by the hand.

9. The substrate transport robot according to claim 8, wherein the hand includes a blade member on which a plate-shaped workpiece is placed and a hand base portion on which the blade member is positioned, the movable support portion is rod-shaped and extends in the front-rear direction along the blade member from the inside to the outside of the hand base portion, and the force sensor is positioned in the rod-shaped movable support portion in the internal part of the hand base portion.

10. The substrate transport robot according to claim 1, wherein the force sensor includes a multi-axis force sensor that detects forces in a plurality of axial directions including the direction of movement of the movable support, the control unit controls the movement of the movable support by the drive unit based on the force detection result in the direction of movement by the multi-axis force sensor, and determines an abnormality in the holding state of the workpiece by the hand based on the force detection result in the axial direction different from the direction of movement by the multi-axis force sensor.

11. The substrate transfer robot according to claim 10, wherein the control unit outputs error information indicating an abnormality in the workpiece holding state when it determines that there is an abnormality in the workpiece holding state.

12. The substrate transport robot according to claim 2, wherein the control unit controls the movement of the movable support by controlling the operation of the motor based on the detection result of the force sensor without detecting the rotation of the motor.

13. The substrate transport robot according to claim 2, wherein the drive unit includes a stepping motor that rotates in response to a pulse signal, and the control unit controls the movement of the movable support unit by the operation of the stepping motor by controlling the pulse signal based on the detection result of the force sensor.

14. The substrate transport robot according to claim 1, wherein the control unit controls the movement of the movable support unit based on the detection result from the force sensor, thereby adjusting the force applied to the workpiece and holding the workpiece between the movable support unit and the fixed support unit.

Images