Industrial robot and control method for industrial robot

Abstract

To provide an industrial robot capable of shortening a transfer time of a transfer object from a reception part to a delivery part even if the transfer object can be placed in the delivery part after a position and a direction of the transfer object, which is placed in the reception part, in a horizontal direction are corrected.SOLUTION: When performing first operation for moving a hand 6 to a reception part 4, an industrial robot 1 acquires position data (first position data and second position data) of the hand 6 in a Y direction at the time when a transfer object 2 is respectively detected by two detection mechanism 33 and when performing second operation for moving the hand 6 receiving the transfer object 2 in the reception part 4 closer to a main body part 10, the industrial robot acquires position data (third position data) of the transfer object 2 detected by a detection mechanism 34 in an X direction and when performing third operation for moving the hand 6 on which the transfer object 2 is loaded to a delivery part 5, a position and a direction of the hand 6 are corrected on the basis of, the first to third position data.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an industrial robot that transports rectangular or square objects, and also to a control method for such an industrial robot. [Background technology]

[0002] Conventionally, robots that transport glass substrates between cassettes are known (see, for example, Patent Document 1). The robot described in Patent Document 1 includes a horizontal movement unit, a robot hand unit, and a connecting unit that connects the horizontal movement unit and the robot hand unit. The horizontal movement unit includes a slider that moves left and right along a guide rail. The robot hand unit includes a first arm rotatably connected to the connecting unit, a second arm rotatably connected to the tip of the first arm, and a hand rotatably connected to the tip of the second arm and on which a glass substrate is mounted.

[0003] In the robot described in Patent Document 1, two first distance sensors are attached to the upper surface of the hand to detect the distance to the front end surface of the glass substrate. The two first distance sensors are arranged with a gap between them in the left-right direction. A position detection sensor is attached to the connecting part via a support arm to detect the position of the left end surface of the glass substrate placed on the hand located at the origin position.

[0004] A control device is connected to the robot described in Patent Document 1. Based on the detection results of the two first distance sensors, the control device calculates a correction amount corresponding to the amount of deviation of the glass substrate placed in the cassette in the forward / backward direction from a reference position and a correction amount corresponding to the amount of inclination of the glass substrate placed in the cassette from the reference position when viewed from the top / bottom direction. Furthermore, based on the detection results of the position detection sensors, the control device calculates a correction amount corresponding to the amount of deviation of the glass substrate placed on the hand in the left / right direction from the reference position.

[0005] The robot described in Patent Document 1 corrects the orientation and front-rear position of the hand based on a correction amount corresponding to the amount of deviation of the glass substrate in the front-rear direction from a reference position and a correction amount corresponding to the amount of inclination of the glass substrate from the reference position before loading the glass substrate placed in the cassette onto the hand. Furthermore, when the robot carries the glass substrate loaded on the hand into a cassette for the next process and places it there, it corrects the left-right position of the hand based on a correction amount corresponding to the amount of deviation of the glass substrate in the left-right direction from the reference position. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 9-162257 Summary of the Invention [Problem to be solved by the invention]

[0007] In the robot described in Patent Document 1, the horizontal position and orientation of the glass substrate placed in the cassette are corrected before placing the glass substrate in the cassette for the next process, so the orientation and position of the hand are corrected both when receiving and carrying out the glass substrate from the cassette and when carrying the glass substrate into and handing over the cassette for the next process. Therefore, with this robot, there is a risk that the time required to transport the glass substrate between cassettes will be long.

[0008] For example, when receiving and transporting a glass substrate from a cassette, if the hand is moved in the corrected orientation, there is a risk that the glass substrate loaded on the hand or the hand may interfere with the components of the cassette.In this case, it is necessary to change the orientation of the hand before moving it out of the cassette so that the glass substrate or the hand does not interfere with the components of the cassette.In this case, it takes longer to transport the glass substrate between cassettes.

[0009] Therefore, the object of the present invention is to provide an industrial robot that transports an object to be transported from a designated receiving section and transports the object to a designated delivery section, which is capable of shortening the transport time of the object from the receiving section to the delivery section, even if it is possible to correct the horizontal position and orientation of the object placed in the receiving section before placing the object in the delivery section.

[0010] Another object of the present invention is to provide a control method for an industrial robot that transports an object to be transported from a designated receiving section and transfers it to a designated delivery section, which makes it possible to shorten the transport time of the object from the receiving section to the delivery section, even if it is possible to correct the horizontal position and orientation of the object placed in the receiving section before placing it in the delivery section. [Means for solving the problem]

[0011] In order to solve the above problems, the industrial robot of the present invention is an industrial robot that transports rectangular or square-shaped transport objects, and includes a hand on which the transport object is placed and which is movable in a horizontal direction, an arm to which the hand is connected, a main body to which the arm is connected so as to be rotatable about the vertical direction as the axis of rotation, two optical first detection mechanisms attached to the hand, a second optical detection mechanism attached to the main body, and a control unit that controls the industrial robot, and the industrial robot is configured to receive a predetermined receiving portion when the tip of the hand is moved in a direction away from the main body. The position of the hand when the hand receives the object placed on the hand is defined as the receiving position, and the position of the hand when the hand delivers the object loaded on the hand to a predetermined delivery section with the tip of the hand moving in a direction away from the main body is defined as the delivery position. The first action is the action of the hand moving to the receiving position so that the tip of the hand moves away from the main body, the second action is the action of the hand receiving the object at the receiving position after the first action and moving so that the tip of the hand approaches the main body, and the second action is the action of the hand moving away from the main body after the second action. and a third operation, which is an operation in which the hand carrying the transport object moves to a delivery position so as to move in the same direction as the transport object. When the industrial robot performs the first operation and the second operation, the hand moves linearly while facing in a fixed direction relative to the main body. If the direction of movement of the hand when the industrial robot performs the first operation and the second operation is defined as a first direction and a direction perpendicular to the first direction and the up-down direction is defined as a second direction, the first detection mechanism is a reflective detection mechanism including a first light-emitting unit and a first light-receiving unit that receives light emitted from the first light-emitting unit and reflected by the transport object, and the two first detection units The mechanisms are arranged with a gap between them in the second direction, and the second detection mechanism is a transmission type detection mechanism having a second light receiving unit consisting of a line sensor or an area sensor, and a second light emitting unit arranged opposite the second light receiving unit with a predetermined gap between it and the second light receiving unit in the up-down direction, and when the industrial robot performs a first operation, the two first detection mechanisms pass below the transport object placed on the receiving unit, and when the industrial robot performs a second operation, one end face in the second direction of the transport object mounted on the hand passes between the second light receiving unit and the second light emitting unit, and the control unitWhen the industrial robot performs a first operation, it acquires first position data, which is data on the position of the hand in the first direction when one of the two first detection mechanisms detects the transport object, and second position data, which is data on the position of the hand in the first direction when the other of the two first detection mechanisms detects the transport object; when the industrial robot performs a second operation, it acquires third position data, which is data on the position in the second direction of one end face of the transport object in the second direction detected by the second detection mechanism when the hand moves to a predetermined measurement position; and when the industrial robot performs a third operation, it corrects the horizontal position and orientation of the hand when it reaches a delivery position based on the first position data, the second position data, and the third position data.

[0012] Furthermore, in order to solve the above-mentioned problems, a control method for an industrial robot of the present invention includes a hand that can carry a rectangular or square-shaped transport object and that can move horizontally, an arm to which the hand is connected, a main body to which the arm is rotatably connected, two first optical detection mechanisms attached to the hand, and a second optical detection mechanism attached to the main body, and the method includes the steps of: a first action in which the hand moves to the receiving position so that the tip of the hand moves away from the main body and receives the transport object placed on a predetermined receiving section with the tip of the hand moving in a direction away from the main body; a second action in which the hand that has received the transport object at the receiving position moves closer to the main body after the first action; and a second action in which the hand with the transport object carried thereon moves away from the main body after the second action, where the position of the hand when the tip of the hand moves away from the main body and receives the transport object placed on the hand is defined as a receiving position and a delivering position, respectively. and a third operation which is an operation when moving to a delivery position, and the hand moves linearly while facing a fixed direction relative to the main body when performing the first operation and the second operation, and the direction of movement of the hand when performing the first operation and the second operation is defined as a first direction, and a direction perpendicular to the first direction and the up-down direction is defined as a second direction, the first detection mechanism is a reflective detection mechanism including a first light-emitting unit and a first light-receiving unit which receives light emitted from the first light-emitting unit and reflected by the transported object, and the two first detection mechanisms are spaced apart in the second direction. a second detection mechanism is a transmission-type detection mechanism having a second light-receiving unit consisting of a line sensor or an area sensor, and a second light-emitting unit arranged facing the second light-receiving unit with a predetermined gap between the second light-receiving unit and the second light-emitting unit in the up-down direction, and when a first operation is performed, the two first detection mechanisms pass below the object to be transported placed on the receiving unit, and when a second operation is performed, one end face in the second direction of the object to be transported mounted on the hand passes between the second light-receiving unit and the second light-emitting unit.The method is characterized in that first position data is acquired, which is data on the position of the hand in the first direction when one of the two first detection mechanisms detects the transport object, and second position data is acquired, which is data on the position of the hand in the first direction when the other of the two first detection mechanisms detects the transport object, and when performing the second operation, third position data is acquired, which is data on the second direction position of one end face in the second direction of the transport object detected by the second detection mechanism when the hand moves to a predetermined measurement position, and when performing the third operation, the horizontal position and orientation of the hand when it reaches the delivery position are corrected based on the first position data, the second position data, and the third position data.

[0013] In the present invention, when the industrial robot performs the third operation, the horizontal position and orientation of the hand when it reaches the transfer position are corrected based on the first position data, the second position data, and the third position data. That is, in the present invention, the horizontal position and orientation of the hand are corrected only when performing the third operation, which is the operation in which the hand carrying the transport object moves to the transfer position so that the tip of the hand moves away from the main body, but the position and orientation of the hand are not corrected when performing the first operation, which is the operation in which the hand moves to the receiving position so that the tip of the hand moves away from the main body. Therefore, in the present invention, even if the horizontal position and orientation of the transport object placed in the receiving section can be corrected before placing the transport object on the transferring section, it is possible to shorten the time it takes to transfer the transport object from the receiving section to the transferring section.

[0014] In the present invention, for example, the arm is composed of multiple arm portions that are rotatably connected to each other and are capable of extending and contracting horizontally, the hand is rotatably connected to the tip side of the arm, and the base end side of the arm is rotatably connected to the main body portion.

[0015] In the present invention, the industrial robot includes, for example, an arm drive mechanism that extends and retracts the arm so that the hand moves linearly relative to the main body while facing in a fixed direction, a rotation mechanism that rotates the main body, and a horizontal movement mechanism that moves the main body in a left-right direction perpendicular to the up-down direction, and the hand moves linearly relative to the main body in a front-to-back direction perpendicular to the up-down and left-right directions when the industrial robot performs a third operation, and the control unit controls the arm drive mechanism, rotation mechanism, and horizontal movement mechanism based on the first position data, second position data, and third position data when the industrial robot performs the third operation to correct the horizontal position and orientation of the hand when it reaches the transfer position.

[0016] In the present invention, for example, the first direction and the left-right direction coincide with each other, and the hand moves linearly in the left-right direction relative to the main body when the industrial robot performs the first operation and the second operation. If the main body cannot be moved in the forward-backward direction, it may be impossible to properly correct the orientation of the hand when performing the first operation. However, in the present invention, even if the orientation of the hand cannot be properly corrected when performing the first operation, it is possible to properly correct the orientation of the hand when performing the third operation.

[0017] In the present invention, the first direction may coincide with the front-rear direction, and the hand may move linearly in the front-rear direction relative to the main body when the industrial robot performs the first operation and the second operation. [Effects of the Invention]

[0018] As described above, in the present invention, in an industrial robot that transports an object to be transported from a designated receiving section and transports the object to a designated delivery section, it is possible to shorten the transport time of the object from the receiving section to the delivery section, even if it is possible to correct the horizontal position and orientation of the object placed in the receiving section before placing the object in the delivery section. [Brief explanation of the drawings]

[0019] [Figure 1]1 is a plan view of an industrial robot according to an embodiment of the present invention; [Figure 2] 2 is a plan view of the industrial robot shown in FIG. 1 in a different state. [Figure 3] FIG. 2 is a rear view of the industrial robot shown in FIG. [Figure 4] FIG. 2 is a block diagram for explaining the configuration of the industrial robot shown in FIG. [Figure 5] 1. FIG. 4 is a diagram for explaining a method for calculating correction values ​​for the horizontal position and orientation of the hand that are corrected when the industrial robot shown in FIG. 1 performs the third operation. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0021] (Configuration of industrial robots) Fig. 1 is a plan view of an industrial robot 1 according to an embodiment of the present invention. Fig. 2 is a plan view of the industrial robot 1 shown in Fig. 1 in a different state. Fig. 3 is a rear view of the industrial robot 1 shown in Fig. 1. Fig. 4 is a block diagram for explaining the configuration of the industrial robot 1 shown in Fig. 1.

[0022] The industrial robot 1 (hereinafter referred to as "robot 1") of this embodiment is a horizontal articulated robot that transports objects to be transported, such as glass substrates 2 for organic EL displays or glass substrates 2 for liquid crystal displays (hereinafter referred to as "substrates 2"). The substrates 2 are formed in the shape of a rectangular or square flat plate. The robot 1 transports the substrates 2, for example, from storage cassettes 3 and 4 that store a plurality of substrates 2 to a processing device 5 that performs a predetermined process on the substrates 2. That is, the robot 1, for example, unloads the substrates 2 from the storage cassettes 3 and 4 and loads the substrates 2 unloaded from the storage cassettes 3 and 4 into the processing device 5.

[0023] In the following description, the Y direction in Fig. 1, etc., which is perpendicular to the up-down direction, will be referred to as the "left-right direction," and the X direction in Fig. 1, etc., which is perpendicular to the up-down direction and the left-right direction, will be referred to as the "front-to-back direction." Furthermore, the Y1 direction side in Fig. 1, etc., which is one side of the left-to-right direction, will be referred to as the "right" side, and the Y2 direction side in Fig. 1, etc., which is the opposite side, will be referred to as the "left" side, and the X1 direction side in Fig. 1, etc., which is one side of the front-to-back direction, will be referred to as the "front" side, and the X2 direction side in Fig. 1, etc., which is the opposite side, will be referred to as the "rear" side.

[0024] The storage cassettes 3 and 4 store multiple substrates 2 stacked one on top of the other with a gap between them in the vertical direction. In this embodiment, the storage cassette 3 is located in front of the robot 1, and the storage cassette 4 is located on the right side of the robot 1. The processing device 5 is located behind the robot 1. The end faces of the substrates 2 stored in the storage cassettes 3 and 4 and the processing device 5 are approximately parallel to the front-to-back or left-to-right direction.

[0025] The robot 1 comprises two hands 6 and 7 on which a substrate 2 is mounted and which are movable in the horizontal direction, an arm 8 to which the hand 6 is connected, an arm 9 to which the hand 7 is connected, a main body 10 to which the arms 8 and 9 are rotatably connected, a base 11 to which the main body 10 is rotatably connected, and a base 12 that holds the base 11 so as to enable linear movement in the horizontal direction. The main body 10 comprises arm supports 15 that support the base ends of the arms 8 and 9 and are movable up and down, a support frame 16 that supports the arm support 15 so that it can be moved up and down, and a swivel frame 17 that forms the lower end portion of the main body 10.

[0026] The hand 6 is rotatably connected to the tip end of the arm 8 with the vertical direction as the axis of rotation, and the hand 7 is rotatably connected to the tip end of the arm 9 with the vertical direction as the axis of rotation. The hand 7 is arranged below the hand 6. The arm 8 is arranged above the hand 6. The arm 9 is arranged below the hand 7. The base ends of the arms 8 and 9 are rotatably connected to the main body 10 with the vertical direction as the axis of rotation. Specifically, the base ends of the arms 8 and 9 are rotatably connected to the arm support 15. When viewed from the vertical direction, the center of rotation of the arm 8 relative to the main body 10 and the center of rotation of the arm 9 relative to the main body 10 coincide with each other.

[0027] The hands 6 and 7 each include a hand base 18 rotatably connected to the tip end of the arms 8 and 9, and a plurality of linear forks 19 on the upper surface of which the substrate 2 is placed. The hands 6 and 7 in this embodiment include four forks 19. The four forks 19 protrude horizontally from the hand base 18 in the same direction. The four forks 19 are arranged parallel to one another. The forks 19 of the hand 6 and the forks 19 of the hand 7 protrude in the same direction.

[0028] The arms 8 and 9 are articulated arms that extend and retract in the horizontal direction. The arms 8 and 9 are composed of a first arm unit 21 and a second arm unit 22 that are rotatably connected to each other. That is, the arms 8 and 9 are composed of two arms that are rotatably connected to each other and are extendable and retractable in the horizontal direction. The base end side of the first arm unit 21 is rotatably connected to the main body unit 10 (specifically, the arm support 15). The base end side of the second arm unit 22 is rotatably connected to the tip side of the first arm unit 21. The hands 6 and 7 are rotatably connected to the tip side of the second arm unit 22. In the arm 8, the second arm unit 22 is arranged below the first arm unit 21, and in the arm 9, the second arm unit 22 is arranged above the first arm unit 21.

[0029] The base end side of arm 8 is rotatably connected to the upper end side of arm support 15, and the base end side of arm 9 is rotatably connected to the lower end side of arm support 15. In the horizontal direction, the distance between the rotation center of first arm section 21 relative to arm support 15 and the rotation center of second arm section 22 relative to first arm section 21 is equal to the distance between the rotation center of second arm section 22 relative to first arm section 21 and the rotation center of hands 6, 7 relative to second arm section 22.

[0030] The arms 8, 9 are horizontally extendable between a position where the arms 8, 9 extend so that the tips of the hands 6, 7 (i.e., the tips of the forks 19) move away from (away from) the main body 10, and a position where the arms 8, 9 retract so that the tips of the hands 6, 7 move closer to the main body 10. When the arms 8, 9 extend and retract by the same amount relative to the main body 10, the hands 6 and 7 overlap in the vertical direction, and the arms 8 and 9 overlap in the vertical direction.

[0031] The support frame 16 holds the hands 6, 7 and the arms 8, 9 via the arm supports 15 so that they can be raised and lowered. The support frame 16 includes a columnar first support frame 23 that holds the arm support 15 so that it can be raised and lowered, and a columnar second support frame 24 that holds the first support frame 23 so that it can be raised and lowered. The swivel frame 17 is formed in a flat, approximately rectangular parallelepiped shape that is thin in the vertical direction. The swivel frame 17 is also formed in a long, slender rectangular parallelepiped shape. The lower end of the second support frame 24 is fixed to the upper surface of the tip side of the swivel frame 17. The base end side of the swivel frame 17 is rotatably connected to the base 11 with the vertical direction as the axis of rotation. The swivel frame 17 is positioned above the base 11. The base 11 is movable linearly in the left-right direction relative to the base 12.

[0032] The robot 1 also includes an arm drive mechanism 27 that extends and retracts the arm 8, an arm drive mechanism 28 that extends and retracts the arm 9, a rotation mechanism 29 that rotates the main body 10, a lifting mechanism 30 that raises and lowers the hands 6, 7 and the arms 8, 9, a horizontal movement mechanism 31 that moves the main body 10 left and right together with the base 11, and a control unit 32 that controls the robot 1. The robot 1 transports the substrate 2 by a combination of the extension and retraction movements of the arms 8, 9, the lifting and lowering movements of the arms 8, 9, etc., and the rotation and horizontal movement of the main body 10.

[0033] The robot 1 also includes two detection mechanisms 33 and one detection mechanism 34 for detecting the position of the substrate 2 mounted on the hand 6, and two detection mechanisms 33 and one detection mechanism 34 for detecting the position of the substrate 2 mounted on the hand 7. That is, the robot 1 includes four detection mechanisms 33 and two detection mechanisms 34. The detection mechanism 33 in this embodiment is a first detection mechanism, and the detection mechanism 34 is a second detection mechanism.

[0034] The arm drive mechanism 27 includes a motor as a drive source, a power transmission mechanism that transmits the power of the motor to the arm 8 and the hand 6, and an encoder that detects the amount of rotation of the motor. The motor is a servo motor and is controlled based on the detection results of the encoder. The arm drive mechanism 27 extends and retracts the arm 8 in the horizontal direction so that the hand 6 moves linearly with respect to the main body 10 while facing in a fixed direction. The arm drive mechanism 27 is electrically connected to the control unit 32. Specifically, the motor, encoder, etc. of the arm drive mechanism 27 are electrically connected to the control unit 32.

[0035] Similar to the arm driving mechanism 27, the arm driving mechanism 28 includes a motor as a driving source, a power transmission mechanism that transmits the power of the motor to the arm 9 and the hand 7, and an encoder for detecting the amount of rotation of the motor. The motor is a servo motor and is controlled based on the detection result of the encoder. The arm driving mechanism 28 extends and retracts the arm 9 in the horizontal direction so that the hand 7 moves linearly with respect to the main body 10 while facing in a fixed direction. The arm driving mechanism 28 is electrically connected to the control unit 32. Specifically, the motor, encoder, etc. of the arm driving mechanism 28 are electrically connected to the control unit 32.

[0036] The rotation mechanism 29 rotates the swivel frame 17 relative to the base 11, with the vertical direction as the axis of rotation. That is, the rotation mechanism 29 rotates the arms 8 and 9 together with the main body 10, with the vertical direction as the axis of rotation. The rotation mechanism 29 includes a motor as a drive source, a power transmission mechanism that transmits the power of the motor to the swivel frame 17, and an encoder that detects the amount of rotation of the motor. The motor is a servo motor and is controlled based on the detection result of the encoder. The rotation mechanism 29 is electrically connected to the control unit 32. Specifically, the motor, encoder, etc. of the rotation mechanism 29 are electrically connected to the control unit 32.

[0037] The lifting mechanism 30 raises and lowers the first support frame 23 relative to the second support frame 24, and raises and lowers the arm support 15 relative to the first support frame 23. The lifting mechanism 30 includes a motor that raises and lowers the arm support 15 and raises and lowers the first support frame 23, a reducer that transmits the power of the motor to the first support frame 23 and the arm support 15, and an encoder that detects the amount of rotation of the motor. The motor is a servo motor, and is controlled based on the detection result of the encoder.

[0038] The lifting mechanism 30 is electrically connected to the control unit 32. Specifically, the motor, encoder, etc. of the lifting mechanism 30 are electrically connected to the control unit 32. Note that the robot 1 may be provided with a separate lifting mechanism for raising and lowering the arm support 15 relative to the first support frame 23 and a separate lifting mechanism for raising and lowering the first support frame 23 relative to the second support frame 24.

[0039] The horizontal movement mechanism 31 linearly moves the base 11 in the left-right direction relative to the base 12. That is, the horizontal movement mechanism 31 linearly moves the main body 10 and the arms 8 and 9 in the left-right direction together with the base 11. The horizontal movement mechanism 31 includes a motor as a drive source, a power transmission mechanism that transmits the power of the motor to the base 11, and an encoder that detects the amount of rotation of the motor. The motor is a servo motor and is controlled based on the detection result of the encoder. The horizontal movement mechanism 31 is electrically connected to the control unit 32. Specifically, the motor, encoder, etc. of the horizontal movement mechanism 31 are electrically connected to the control unit 32.

[0040] The detection mechanism 33 is an optical detection mechanism. The detection mechanism 33 is a reflective detection mechanism having a light-emitting unit 37 and a light-receiving unit 38 that receives light emitted from the light-emitting unit 37 and reflected by the substrate 2. The detection mechanisms 33 are attached to each of the hands 6 and 7. Specifically, two detection mechanisms 33 are attached to the hand 6, and two detection mechanisms 33 are attached to the hand 7. The detection mechanisms 33 are electrically connected to the control unit 32. In this embodiment, the light-emitting unit 37 is a first light-emitting unit, and the light-receiving unit 38 is a first light-receiving unit.

[0041] The detection mechanism 33 is attached to the hands 6, 7 so that the light-emitting surface of the light-emitting unit 37 and the light-receiving surface of the light-receiving unit 38 face upward. The detection mechanism 33 is also attached to the upper surface side of the forks 19. In this embodiment, the detection mechanism 33 is attached to two of the four forks 19 held by each of the hands 6, 7, that are located on the inside in a direction perpendicular to the longitudinal direction of the forks 19. The detection mechanism 33 is also attached to the tip side of the forks 19.

[0042] The two detection mechanisms 33 attached to each of the hands 6 and 7 are arranged at the same position in the longitudinal direction of the forks 19. The two detection mechanisms 33 attached to each of the hands 6 and 7 are arranged with a gap between them in a direction perpendicular to the longitudinal direction of the forks 19. The detection mechanisms 33 may be attached to the two forks 19 that are arranged on the outer sides in the direction perpendicular to the longitudinal direction of the forks 19, out of the four forks 19 that each of the hands 6 and 7 has. The detection mechanisms 33 may also be attached to the base ends of the forks 19.

[0043] The detection mechanism 34 is an optical detection mechanism. The detection mechanism 34 is a transmission type detection mechanism having a light-emitting unit 39 and a light-receiving unit 40 arranged opposite the light-emitting unit 39. The light-emitting unit 39 is arranged opposite the light-receiving unit 40 with a predetermined gap between them in the vertical direction. The light-receiving unit 40 in this embodiment is a line sensor. The light-receiving unit 40 has multiple light-receiving elements arranged in a line. The detection mechanism 34 is electrically connected to the control unit 32. The light-emitting unit 39 in this embodiment is a second light-emitting unit, and the light-receiving unit 40 is a second light-receiving unit.

[0044] The detection mechanism 34 is attached to the main body 10. Specifically, the detection mechanism 34 is fixed to a sensor fixing member 42 that is fixed to the arm support 15, and is fixed to the arm support 15 via the sensor fixing member 42. In this embodiment, a detection mechanism 34 for detecting the position of the substrate 2 mounted on the hand 6 and a detection mechanism 34 for detecting the position of the substrate 2 mounted on the hand 7 are fixed to the arm support 15 via the sensor fixing member 42. That is, two detection mechanisms 34 are fixed to the arm support 15. The two detection mechanisms 34 overlap in the vertical direction.

[0045] The detection mechanism 34 rotates together with the arm support 15 and moves up and down together with the arm support 15. As described above, a plurality of light receiving elements are arranged in a row in the light receiving unit 40. Specifically, when the longitudinal direction of the fork 19 and the front-to-rear direction coincide with each other, a plurality of light receiving elements are arranged in a row in the left-to-right direction in the light receiving unit 40, and when the longitudinal direction of the fork 19 and the left-to-right direction coincide with each other, a plurality of light receiving elements are arranged in a row in the front-to-rear direction in the light receiving unit 40.

[0046] As described above, the robot 1 transports the substrate 2 from the storage cassettes 3, 4 to the processing device 5. Also, as described above, the arms 8, 9 are horizontally extendable between an extended position where the arms 8, 9 extend so that the tips of the hands 6, 7 move away from the main body 10, and a retracted position where the arms 8, 9 move so that the tips of the hands 6, 7 move closer to the main body 10. In this embodiment, when the robot 1 receives the substrate 2 from the storage cassettes 3, 4 and when the robot 1 delivers the substrate 2 to the processing device 5, the arms 8, 9 are extended and the tips of the hands 6, 7 move in a direction away from the main body 10.

[0047] If the position of the hand 6 (the position shown in Figure 1) when the tip of the hand 6 has moved in a direction away from the main body 10 (i.e., when the arm 8 is extended) and the hand 6 receives the substrate 2 placed in the storage cassette 3 by loading it onto the hand 6 is defined as hand position 6A, and the position of the hand 6 when the tip of the hand 6 has moved in a direction away from the main body 10 (i.e., when the arm 8 is extended) and the hand 6 delivers the substrate 2 loaded on the hand 6 to the processing device 5 is defined as hand position 6B, the robot 1 performs operation M11, which is an operation when the hand 6 moves to hand position 6A so that the tip of the hand 6 moves away from the main body 10, operation M12, which is an operation when the hand 6, having received the substrate 2 at hand position 6A, moves so that the tip of the hand 6 approaches the main body 10 after operation M11, and operation M13, which is an operation when the hand 6 with the substrate 2 loaded thereon moves to hand position 6B so that the tip of the hand 6 moves away from the main body 10 after operation M12. In operations M11 and M13, the retracted arm 8 is extended, and in operation M12, the extended arm 8 is retracted.

[0048] Furthermore, if the position of the hand 6 when the tip of the hand 6 moves in a direction away from the main body 10 and loads and receives the substrate 2 placed in the storage cassette 4 onto the hand 6 (the position shown in FIG. 2) is defined as hand position 6C, the robot 1 performs operation M14, in which the hand 6 moves to hand position 6C so that the tip of the hand 6 moves away from the main body 10, operation M15, in which, after operation M14, the hand 6 that has received the substrate 2 at hand position 6C moves so that the tip of the hand 6 approaches the main body 10, and operation M16, in which, after operation M15, the hand 6 with the substrate 2 loaded thereon moves to hand position 6B so that the tip of the hand 6 moves away from the main body 10. In operations M14 and M16, the retracted arm 8 extends, and in operation M15, the extended arm 8 retracts.

[0049] Similarly, if the position of the hand 7 when the tip of the hand 7 moves away from the main body 10 (i.e., when the arm 9 is extended) and the hand 7 receives the substrate 2 placed in the storage cassette 3 by loading it onto the hand 7, is defined as hand position 7A, and the position of the hand 7 when the tip of the hand 7 moves away from the main body 10 (i.e., when the arm 9 is extended) and the hand 7 delivers the substrate 2 loaded on the hand 7 to the processing device 5, the robot 1 performs operation M21, which is the operation when the hand 7 moves to hand position 7A so that the tip of the hand 7 moves away from the main body 10, operation M22, which is the operation when the hand 7 receives the substrate 2 at hand position 7A and moves so that the tip of the hand 7 approaches the main body 10 after operation M21, and operation M23, which is the operation when the hand 7 with the substrate 2 loaded moves to hand position 7B so that the tip of the hand 7 moves away from the main body 10 after operation M22. In operations M21 and M23, the retracted arm 9 is extended, and in operation M22, the extended arm 9 is retracted.

[0050] Furthermore, if the position of the hand 7 when the tip of the hand 7 moves in a direction away from the main body 10 and loads and receives the substrate 2 placed in the storage cassette 4 onto the hand 7 is defined as hand position 7C, the robot 1 performs operation M24, in which the hand 7 moves to hand position 7C so that the tip of the hand 7 moves away from the main body 10, operation M25, after operation M24, in which the hand 7 that has received the substrate 2 at hand position 7C moves so that the tip of the hand 7 approaches the main body 10, and operation M26, after operation M25, in which the hand 7 with the substrate 2 loaded moves to hand position 7B so that the tip of the hand 7 moves away from the main body 10. In operations M24 and M26, the retracted arm 9 extends, and in operation M25, the extended arm 9 retracts.

[0051] When operations M12 and M15 are completed, the rotation radius (turning radius) of the main body 10, including the board 2 loaded on the hand 6, the hand 6, and the arm 8, is minimized. Similarly, when operations M22 and M25 are completed, the rotation radius of the main body 10, including the board 2 loaded on the hand 7, the hand 7, and the arm 9, is minimized.

[0052] As described above, the arm driving mechanism 27 extends and retracts the arm 8 so that the hand 6 moves linearly while facing a fixed direction relative to the main body 10, and the arm driving mechanism 28 extends and retracts the arm 9 so that the hand 7 moves linearly while facing a fixed direction relative to the main body 10. That is, when the robot 1 performs operations M11 to M16, the hand 6 moves linearly while facing a fixed direction relative to the main body 10, and when the robot 1 performs operations M21 to M26, the hand 7 moves linearly while facing a fixed direction relative to the main body 10.

[0053] In this embodiment, the storage cassette 3 is disposed in front of the robot 1, the storage cassette 4 is disposed to the right of the robot 1, and the processing device 5 is disposed behind the robot 1, so the hand 6 moves linearly in the front-to-back direction relative to the main body 10 when the robot 1 performs operations M11 to M13, and M16, and moves linearly in the left-to-right direction relative to the main body 10 when the robot 1 performs operations M14 and M15. In addition, the hand 7 moves linearly in the front-to-back direction relative to the main body 10 when the robot 1 performs operations M21 to M23, and M26, and moves linearly in the left-to-right direction relative to the main body 10 when the robot 1 performs operations M24 and M25.

[0054] Specifically, when the robot 1 performs operation M11, the hand 6 moves linearly forward relative to the main body 10 with the tip of the fork 19 facing forward; when the robot 1 performs operation M12, the hand 6 moves linearly backward relative to the main body 10 with the tip of the fork 19 facing forward; when the robot 1 performs operation M14, the hand 6 moves linearly to the right relative to the main body 10 with the tip of the fork 19 facing right; when the robot 1 performs operation M15, the hand 6 moves linearly to the left relative to the main body 10 with the tip of the fork 19 facing right; and when the robot 1 performs operations M13 and M16, the hand 6 moves linearly backward relative to the main body 10 with the tip of the fork 19 facing backward.

[0055] Similarly, when the robot 1 performs operation M21, the hand 7 moves linearly forward relative to the main body 10 with the tip of the fork 19 facing forward; when the robot 1 performs operation M22, the hand 7 moves linearly backward relative to the main body 10 with the tip of the fork 19 facing forward; when the robot 1 performs operation M24, the hand 7 moves linearly to the right relative to the main body 10 with the tip of the fork 19 facing right; when the robot 1 performs operation M25, the hand 7 moves linearly to the left relative to the main body 10 with the tip of the fork 19 facing right; and when the robot 1 performs operations M23 and M26, the hand 7 moves linearly backward relative to the main body 10 with the tip of the fork 19 facing backward.

[0056] When the robot 1 performs operation M11, the two detection mechanisms 33 attached to the hand 6 pass below the substrate 2 placed in the storage cassette 3 (specifically, below the substrate 2 that will be loaded onto the hand 6 after operation M11), and when the robot 1 performs operation M21, the two detection mechanisms 33 attached to the hand 7 pass below the substrate 2 placed in the storage cassette 3 (specifically, below the substrate 2 that will be loaded onto the hand 7 after operation M21).

[0057] When the robot 1 performs operation M14, the two detection mechanisms 33 attached to the hand 6 pass below the substrate 2 placed in the storage cassette 4 (specifically, below the substrate 2 that will be loaded onto the hand 6 after operation M14), and when the robot 1 performs operation M24, the two detection mechanisms 33 attached to the hand 7 pass below the substrate 2 placed in the storage cassette 4 (specifically, below the substrate 2 that will be loaded onto the hand 7 after operation M24).

[0058] When the robot 1 performs operation M12, one left-right end face of the board 2 mounted on the hand 6 passes between the light-emitting unit 39 and the light-receiving unit 40 of one of the two detection mechanisms 34, and when the robot 1 performs operation M22, one left-right end face of the board 2 mounted on the hand 7 passes between the light-emitting unit 39 and the light-receiving unit 40 of the other detection mechanism 34. In this embodiment, when the robot 1 performs operations M12 and M22, the detection mechanism 34 is disposed to the right of the hands 6 and 7, and the right end faces of the board 2 mounted on the hands 6 and 7 pass between the light-emitting unit 39 and the light-receiving unit 40.

[0059] When the robot 1 performs operation M15, one end surface in the front-to-rear direction of the substrate 2 mounted on the hand 6 passes between the light-emitting unit 39 and the light-receiving unit 40 of one of the two detection mechanisms 34, and when the robot 1 performs operation M25, one end surface in the front-to-rear direction of the substrate 2 mounted on the hand 7 passes between the light-emitting unit 39 and the light-receiving unit 40 of the other detection mechanism 34. In this embodiment, when the robot 1 performs operations M15 and M25, the detection mechanism 34 is disposed behind the hands 6 and 7, and the rear end surfaces of the substrate 2 mounted on the hands 6 and 7 pass between the light-emitting unit 39 and the light-receiving unit 40.

[0060] That is, the detection mechanism 34 is disposed at a position where the right end surface of the board 2 carried by the hands 6 and 7 passes between the light-emitting unit 39 and the light-receiving unit 40 when the robot 1 performs operations M12 and M22, and where the rear end surface of the board 2 carried by the hands 6 and 7 passes between the light-emitting unit 39 and the light-receiving unit 40 when the robot 1 performs operations M15 and M25. The detection mechanism 34 is disposed behind the rear end surface of the board 2 carried by the hands 6 and 7 disposed at hand positions 6A and 7A, and to the left of the left end surface of the board 2 carried by the hands 6 and 7 disposed at hand positions 6C and 7C. The detection mechanism 34 is disposed between the front and rear end surfaces of the board 2 carried by the hands 6 and 7 after operations M12 and M22 are completed, in the front-rear direction, and between the right and left end surfaces of the board 2 carried by the hands 6 and 7 after operations M15 and M25 are completed, in the left-right direction.

[0061] As described above, the light receiving unit 40 is a line sensor in which a plurality of light receiving elements are arranged in a row, so that the detection mechanism 34 can detect the left-right position of the right end surface of the substrate 2 placed on the hands 6 and 7 after operations M12 and M22 are completed. Also, the detection mechanism 34 can detect the front-rear position of the rear end surface of the substrate 2 placed on the hands 6 and 7 after operations M15 and M25 are completed.

[0062] The robot 1 performs a rotational motion to rotate the main body 10 between operations M12 and M13, and between operations M15 and M16. At this time, the arm 9 is also retracted. The robot 1 also performs a rotational motion to rotate the main body 10 between operations M22 and M23, and between operations M25 and M26. At this time, the arm 8 is also retracted. The robot 1 also performs a lifting / lowering motion of the arm support 15 and a left-right movement motion of the main body 10 between operations M12 and M13, between operations M15 and M16, between operations M22 and M23, and between operations M25 and M26, as necessary. The robot 1 may also perform a lifting / lowering motion of the arm support 15 and a left-right movement motion of the main body 10 when performing operations M11 to M16 and M21 to M26, as necessary.

[0063] (Robot control method) When the robot 1 performs operation M11, the control unit 32 acquires position data D1, which is data on the position of the hand 6 in the front-to-rear direction when one of the two detection mechanisms 33 attached to the hand 6 detects the substrate 2 (specifically, when one detection mechanism 33 detects the rear end surface of the substrate 2 placed in the storage cassette 3 (i.e., when one detection mechanism 33 first detects the substrate 2)), and position data D2, which is data on the position of the hand 6 in the front-to-rear direction when the other detection mechanism 33 detects the substrate 2 (specifically, when the other detection mechanism 33 detects the rear end surface of the substrate 2 placed in the storage cassette 3 (i.e., when the other detection mechanism 33 first detects the substrate 2)). The control unit 32 acquires the position data D1 and D2 based on the detection results of the detection mechanisms 33 and the detection results of the encoder of the arm drive mechanism 27.

[0064] The control unit 32 identifies the front-rear position and orientation (tilt of the substrate 2 in the horizontal plane) of the substrate 2 placed in the storage cassette 3 based on the position data D1 and D2. The control unit 32 also compares the identified front-rear position and orientation of the substrate 2 with the front-rear position and orientation of the substrate 2 previously taught to the robot 1, and corrects the front-rear position and orientation of the hand 6 when it reaches the hand position 6A based on the comparison result when the robot 1 performs operation M11. That is, the control unit 32 corrects the front-rear position and orientation of the hand 6 when it reaches the hand position 6A based on the position data D1 and D2 when the robot 1 performs operation M11.

[0065] Specifically, when the robot 1 performs operation M11, the control unit 32 controls the arm drive mechanism 27, the rotation mechanism 29, and the horizontal movement mechanism 31 based on the position data D1 and D2 to correct the front-to-rear position and orientation of the hand 6 when it reaches the hand position 6A. Furthermore, when the robot 1 performs operation M11, the control unit 32 corrects the front-to-rear position and orientation of the hand 6 when it reaches the hand position 6A based on the position data D1 and D2 so that the position of the substrate 2 loaded on the hand 6 in the front-to-rear direction is appropriate and the orientation of the substrate 2 loaded on the hand 6 is appropriate.

[0066] Furthermore, when the robot 1 performs operation M12, the control unit 32 acquires position data D3, which is data on the left-right position of the right end surface of the substrate 2 detected by the detection mechanism 34 when the hand 6 moves to a predetermined measurement position. The control unit 32 acquires the position data D3 based on the detection result of the detection mechanism 34 and the detection result of the encoder of the arm drive mechanism 27. In this embodiment, for example, the position of the hand 6 when operation M12 is completed is the measurement position, but the measurement position may also be a predetermined position of the hand 6 while operation M12 is being performed.

[0067] The control unit 32 identifies the left-right position of the substrate 2 placed on the hand 6 based on the position data D3. The control unit 32 also compares the identified left-right position of the substrate 2 with the left-right position of the substrate 2 previously taught to the robot 1, and corrects the left-right position of the hand 6 when it reaches hand position 6B based on the comparison result when the robot 1 performs operation M13. That is, the control unit 32 corrects the left-right position of the hand 6 when it reaches hand position 6B based on the position data D3 when the robot 1 performs operation M13.

[0068] Specifically, when the robot 1 performs operation M13, the control unit 32 controls the horizontal movement mechanism 31 based on the position data D3 to correct the left-right position of the hand 6 when it reaches the hand position 6B. Furthermore, when the robot 1 performs operation M13, the control unit 32 corrects the left-right position of the hand 6 when it reaches the hand position 6B based on the position data D3 so that the left-right position of the substrate 2 placed on the processing device 5 is appropriate.

[0069] Similarly, when the robot 1 performs operation M21, the control unit 32 acquires position data D4, which is data on the position of the hand 7 in the front-to-rear direction when one of the two detection mechanisms 33 attached to the hand 7 detects the substrate 2, and position data D5, which is data on the position of the hand 7 in the front-to-rear direction when the other detection mechanism 33 detects the substrate 2. The control unit 32 acquires the position data D4 and D5 based on the detection result of the detection mechanism 33 and the detection result of the encoder of the arm drive mechanism 28.

[0070] Based on the position data D4 and D5, the control unit 32 identifies the front-rear position and orientation of the substrate 2 placed in the storage cassette 3. The control unit 32 also compares the identified front-rear position and orientation of the substrate 2 with the front-rear position and orientation of the substrate 2 previously taught to the robot 1, and corrects the front-rear position and orientation of the hand 7 when it reaches the hand position 7A based on the comparison result when the robot 1 performs operation M21.

[0071] Specifically, when the robot 1 performs operation M21, the control unit 32 controls the arm drive mechanism 28, the rotation mechanism 29, and the horizontal movement mechanism 31 based on the position data D4 and D5 to correct the front-to-rear position and orientation of the hand 7 when it reaches hand position 7A. Furthermore, when the robot 1 performs operation M21, the control unit 32 corrects the front-to-rear position and orientation of the hand 7 when it reaches hand position 7A based on the position data D4 and D5 so that the position of the substrate 2 loaded on the hand 7 is appropriate and the orientation of the substrate 2 loaded on the hand 7 is appropriate.

[0072] Furthermore, when the robot 1 performs operation M22, the control unit 32 acquires position data D6, which is data on the left-right position of the right end surface of the substrate 2 detected by the detection mechanism 34 when the hand 7 moves to a predetermined measurement position. The control unit 32 acquires the position data D6 based on the detection result of the detection mechanism 34 and the detection result of the encoder of the arm drive mechanism 28. In this embodiment, for example, the position of the hand 7 when operation M22 is completed is the measurement position, but the predetermined position of the hand 7 while performing operation M22 may also be the measurement position.

[0073] The control unit 32 identifies the left-right position of the board 2 placed on the hand 7 based on the position data D6. The control unit 32 also compares the identified left-right position of the board 2 with the left-right position of the board 2 previously taught to the robot 1, and corrects the left-right position of the hand 7 when it reaches hand position 7B based on the comparison result when the robot 1 performs operation M23. That is, the control unit 32 corrects the left-right position of the hand 7 when it reaches hand position 7B based on the position data D6 when the robot 1 performs operation M23.

[0074] Specifically, when the robot 1 performs operation M23, the control unit 32 controls the horizontal movement mechanism 31 based on the position data D6 to correct the left-right position of the hand 7 when it reaches the hand position 7B. Furthermore, when the robot 1 performs operation M23, the control unit 32 corrects the left-right position of the hand 7 when it reaches the hand position 7B based on the position data D6 so that the left-right position of the substrate 2 placed on the processing device 5 is appropriate.

[0075] In addition, when the robot 1 performs operation M14, the control unit 32 acquires position data D11, which is data on the left-right position of the hand 6 when one of the two detection mechanisms 33 attached to the hand 6 detects the substrate 2 (specifically, when one detection mechanism 33 detects the left end surface of the substrate 2 placed in the storage cassette 4), and position data D12, which is data on the left-right position of the hand 6 when the other detection mechanism 33 detects the substrate 2 (specifically, when the other detection mechanism 33 detects the left end surface of the substrate 2 placed in the storage cassette 4), and when the robot 1 performs operation M15, acquires position data D13, which is data on the front-to-back position of the rear end surface of the substrate 2 detected by the detection mechanism 34 when the hand 6 moves to a predetermined measurement position.

[0076] In this embodiment, for example, the position of the hand 6 when operation M15 is completed is the measurement position, but a predetermined position of the hand 6 while operation M15 is being performed may also be the measurement position. Furthermore, the control unit 32 acquires position data D11 and D12 based on the detection results of the detection mechanism 33 and the encoder of the arm drive mechanism 27, and acquires position data D13 based on the detection results of the detection mechanism 34 and the encoder of the arm drive mechanism 27. After the robot 1 performs operation M14, when the robot 1 loads the substrate 2 placed in the storage cassette 4 onto the hand 6, the arm 8 is extended so that the hand 6 is positioned at the pre-taught hand position 6C. The substrate 2 is loaded onto the hand 6 in the same state (position and orientation) as it was in the storage cassette 4.

[0077] The control unit 32 identifies the front-rear and left-right positions and orientation of the substrate 2 placed on the hand 6 based on the position data D11 to D13. The control unit 32 also compares the identified front-rear and left-right positions (horizontal position) and orientation of the substrate 2 with the horizontal position and orientation of the substrate 2 previously taught to the robot 1, and corrects the horizontal position and orientation of the hand 6 when it reaches hand position 6B based on the comparison result when the robot 1 performs operation M16. That is, the control unit 32 corrects the horizontal position and orientation of the hand 6 when it reaches hand position 6B based on the position data D11 to D13 when the robot 1 performs operation M16.

[0078] Specifically, when the robot 1 performs operation M16, the control unit 32 controls the arm drive mechanism 27, the rotation mechanism 29, and the horizontal movement mechanism 31 based on the position data D11 to D13 to correct the horizontal position and orientation of the hand 6 when it reaches the hand position 6B. Furthermore, when the robot 1 performs operation M16, the control unit 32 corrects the horizontal position and orientation of the hand 6 when it reaches the hand position 6B based on the position data D11 to D13 so that the horizontal position of the substrate 2 placed on the processing device 5 is appropriate and the orientation of the substrate 2 placed on the processing device 5 is appropriate.

[0079] Similarly, when the robot 1 performs operation M24, the control unit 32 acquires position data D14, which is data on the left-right position of the hand 7 when one of the two detection mechanisms 33 attached to the hand 7 detects the substrate 2, and position data D15, which is data on the left-right position of the hand 7 when the other detection mechanism 33 detects the substrate 2, and when the robot 1 performs operation M25, it acquires position data D16, which is data on the front-to-back position of the rear end surface of the substrate 2 detected by the detection mechanism 34 when the hand 7 moves to a predetermined measurement position.

[0080] In this embodiment, for example, the position of the hand 7 when operation M25 is completed is the measurement position, but a predetermined position of the hand 7 while operation M25 is being performed may also be the measurement position. Furthermore, the control unit 32 acquires position data D14 and D15 based on the detection result of the detection mechanism 33 and the detection result of the encoder of the arm drive mechanism 28, and acquires position data D16 based on the detection result of the detection mechanism 34 and the detection result of the encoder of the arm drive mechanism 28. After the robot 1 performs operation M24, when the robot 1 loads the substrate 2 placed in the storage cassette 4 onto the hand 7, the arm 9 is extended so that the hand 7 is positioned at the pre-taught hand position 7C. The substrate 2 loaded onto the hand 7 is in the same state (position and orientation) as it was in the storage cassette 4.

[0081] The control unit 32 identifies the front-rear and left-right positions and orientation of the substrate 2 placed on the hand 7 based on the position data D14 to D16. The control unit 32 also compares the identified front-rear and left-right positions (horizontal position) and orientation of the substrate 2 with the horizontal position and orientation of the substrate 2 previously taught to the robot 1, and corrects the horizontal position and orientation of the hand 7 when it reaches hand position 7B based on the comparison result when the robot 1 performs operation M26. That is, the control unit 32 corrects the horizontal position and orientation of the hand 7 when it reaches hand position 7B based on the position data D14 to D16 when the robot 1 performs operation M26.

[0082] Specifically, when the robot 1 performs operation M26, the control unit 32 controls the arm drive mechanism 28, the rotation mechanism 29, and the horizontal movement mechanism 31 based on the position data D14 to D16 to correct the horizontal position and orientation of the hand 7 when it reaches hand position 7B. Furthermore, when the robot 1 performs operation M26, the control unit 32 corrects the horizontal position and orientation of the hand 7 when it reaches hand position 7B based on the position data D14 to D16 so that the horizontal position of the substrate 2 placed on the processing device 5 is appropriate and the orientation of the substrate 2 placed on the processing device 5 is appropriate.

[0083] In this embodiment, the storage cassette 4 is a receiving unit, the processing device 5 is a delivering unit, hand positions 6C and 7C are receiving positions, and hand positions 6B and 7B are delivering positions. Operations M14 and M24 are first operations, operations M15 and M25 are second operations, and operations M16 and M26 are third operations. In this embodiment, the left-right direction (Y direction) is a first direction in which the hands 6 and 7 move when the robot 1 performs operations M14 and M24, which are the first operations, and the front-rear direction (X direction) is a second direction perpendicular to the up-down direction and the first direction. When the robot 1 performs operations M14, M15, M24, and M25, the two detection mechanisms 33 attached to the hand 6 and the two detection mechanisms 33 attached to the hand 7 are spaced apart in the front-rear direction.

[0084] (How to calculate hand correction value) FIG. 5 is a diagram for explaining a method of calculating correction values ​​for the horizontal positions and orientations of the hands 6 and 7 that are corrected when the robot 1 shown in FIG. 1 performs the operations M16 and M26.

[0085] For example, when the substrate 2 is placed in the storage cassette 4 as shown by the solid lines in FIG. 5, the correction values ​​for the front-to-back and left-to-right positions and orientations of the hands 6 and 7 to be corrected when the robot 1 performs operations M16 and M26 are calculated as follows. Note that in FIG. 5, the substrate 2 shown by the dashed lines is the substrate 2 placed in the correct position in the storage cassette 4 (i.e., the substrate 2 placed so that there is no need to correct its horizontal position and orientation). In the following, when distinguishing between the substrate 2 shown by the solid lines and the substrate 2 shown by the dashed lines in FIG. 5, the substrate 2 shown by the solid lines will be referred to as substrate 2A, and the substrate 2 shown by the dashed lines will be referred to as substrate 2B. The center of the substrate 2B when viewed from the top-to-bottom direction will be referred to as the origin OR.

[0086] When the robot 1 performs operations M14 and M24, the position of the left end surface of the substrate 2B detected by one of the two detection mechanisms 33 attached to the hands 6 and 7 is defined as PB1, the position of the left end surface of the substrate 2B detected by the other detection mechanism 33 attached to the hands 6 and 7 is defined as PB2, and when the robot 1 performs operations M15 and M25, the position of the rear end surface of the substrate 2B detected by the detection mechanism 34 is defined as PB3. In a coordinate system with the origin OR as the origin, the coordinates of PB1 to PB3 are expressed as follows: PB1(-b3 / 2,-YB / 2) PB2(b3 / 2,-YB / 2) PB3(-XB / 2,b4-YB / 2)

[0087] Here, XB is the width of the substrate 2 in the front-rear direction, and YB is the width of the substrate 2 in the left-right direction. Also, b3 is the distance between PB1 and PB2 in the front-rear direction (i.e., the distance between the two detection mechanisms 33 in the front-rear direction), and the distance between the origin OR and PB1 in the front-rear direction is equal to the distance between the origin OR and PB2 in the front-rear direction. Also, b4 is the distance between the left end surface of the substrate 2 and PB3 in the left-right direction.

[0088] Furthermore, when the robot 1 performs operations M14 and M24, the position of the left end surface of the substrate 2A detected by one of the two detection mechanisms 33 attached to the hands 6 and 7 is defined as P1, the position of the left end surface of the substrate 2A detected by the other detection mechanism 33 attached to the hands 6 and 7 is defined as P2, and when the robot 1 performs operations M15 and M25, the position of the rear end surface of the substrate 2A detected by the detection mechanism 34 is defined as P3. In a coordinate system with the origin OR as the origin, the coordinates of P1 to P3 are expressed as follows: P1(-b3 / 2,-YB / 2+S1) P2(b3 / 2,-YB / 2+S2) P3(-XB / 2-S3,b4-YB / 2) Here, S1 is the distance between PB1 and P1 in the left-right direction, S2 is the distance between PB2 and P2 in the left-right direction, and S3 is the distance between PB3 and P3 in the front-rear direction.

[0089] If the position of the left rear corner of the substrate 2B is the origin WOR, then in a coordinate system with the origin WOR as the origin, a line passing through P1 and P2 is expressed as follows: ax+by+c=0 If the coordinates of P3 are (X0, Y0), the distance L between this line and P3 is: L=|aX0+bY0+c| / (a 2 +b 2 ) 1 / 2 This becomes: Furthermore, if the position of substrate 2B corresponding to P3 on substrate 2A is P3', the coordinates of P3' are expressed as follows in a coordinate system with origin OR as the origin: P3′(−XB / 2,L−YB / 2)

[0090] If the tilt angle of the substrate 2A with respect to the substrate 2B (i.e., the deviation in the orientation of the substrate 2A with respect to the substrate 2B) is θ, then: tanθ=(S2-S1) / b3 Therefore, the angle θ, which is the correction value for the orientation of the substrate 2A relative to the substrate 2B, is calculated by the following formula. θ=tanθ -1 ((S2-S1) / b3) This angle θ is a correction value for the orientation of the hands 6 and 7 when the robot 1 performs the operations M16 and M26.

[0091] In a coordinate system with the origin OR as the origin, if P3' is rotated by an angle θ, the rotated position is P3'r, the coordinates of P3'r are (P3'rx, P3'ry), and the coordinates of P3' are (P3'x, P3'y), then P3'rx, P3'rx, are expressed by the following equations. P3′rx=P3′x×cosθ-P3′y×sinθ P3′ry=P3′x×sinθ+P3′y×cosθ

[0092] In a coordinate system with the origin OR as the origin, if the coordinates of P3 are (P3x, P3y), then in order to calculate the parallel deviation component ΔX between P3 and P3'r and the parallel deviation component ΔY between P3 and P3'r, the coordinates of P3 (P3xr, P3yr) and the coordinates of P3'r (P3'rxr, P3'ryr) can be expressed as follows in a coordinate system rotated by an angle θ around the origin OR. P3′rxr=P3′rx×cosθ+P3′ry×sinθ P3′ryr=-P3′rx×sinθ+P3′ry×cosθ P3xr=P3x×cosθ+P3y×sinθ P3yr = -P3x × sinθ + P3y × cosθ

[0093] Therefore, the parallel deviation components ΔX and ΔY, which are correction values ​​for the substrate 2A relative to the substrate 2B, are calculated by the following equations. ΔX=P3xr-P3′rxr ΔY = P3yr - P3′ryr The parallel deviation component ΔX is a correction value for the positions of the hands 6 and 7 corrected by the horizontal drive mechanism 31 when the robot 1 performs operations M16 and M26. The parallel deviation component ΔY is a correction value for the positions of the hands 6 and 7 corrected by the arm drive mechanisms 27 and 28 when the robot 1 performs operations M16 and M26.

[0094] When the robot 1 performs operations M16 and M26, the correction for the angle θ is made by the rotation mechanism 29, the correction for the parallel deviation component ΔX is made by the horizontal movement mechanism 31, and the correction for the parallel deviation component ΔY is made by the arm drive mechanisms 27 and 28.

[0095] (Main effect of this form) As described above, in this embodiment, when the robot 1 performs operation M16, the control unit 32 corrects the horizontal position and orientation of the hand 6 when it reaches hand position 6B based on the position data D11 to D13, and when the robot 1 performs operation M26, the control unit 32 corrects the horizontal position and orientation of the hand 7 when it reaches hand position 7B based on the position data D14 to D16.

[0096] That is, in this embodiment, the control unit 32 corrects the horizontal position and orientation of the hands 6 and 7 only when the robot 1 performs operations M16 and M26, and does not correct the position and orientation of the hands 6 and 7 when performing operations M14 and M24. Therefore, in this embodiment, even if it is possible to correct the horizontal position and orientation of the substrate 2 placed in the storage cassette 4 before placing the substrate 2 in the processing device 5, it is possible to shorten the time it takes to transport the substrate 2 from the storage cassette 4 to the processing device 5.

[0097] In this embodiment, since the main body 10 cannot be moved in the forward and backward directions, the orientation of the hands 6 and 7 cannot be properly corrected when the robot 1 performs operations M14 and M24. However, in this embodiment, even if the orientation of the hands 6 and 7 cannot be properly corrected when the robot 1 performs operations M14 and M24, it becomes possible to properly correct the orientation of the hands 6 and 7 when the robot 1 performs operations M16 and M26.

[0098] (Example of changing the robot control method) In the embodiment described above, the control unit 32 may acquire position data D1 and D2 when the robot 1 performs operation M11, acquire position data D3 when the robot 1 performs operation M12, and correct the horizontal position and orientation of the hand 6 when it reaches hand position 6B based on the position data D1 to D3 when the robot 1 performs operation M13. In this case, after the robot 1 performs operation M11, when the robot 1 loads the substrate 2 placed in the storage cassette 3 onto the hand 6, the arm 8 is extended so that the hand 6 is positioned at the pre-taught hand position 6A. The substrate 2 is loaded onto the hand 6 in the same state (position and orientation) as it was placed in the storage cassette 3.

[0099] In this case, the control unit 32 identifies the front-rear and left-right positions and orientation of the substrate 2 placed on the hand 6 based on the position data D1 to D3, compares the identified front-rear and left-right positions (horizontal position) and orientation of the substrate 2 with the horizontal position and orientation of the substrate 2 previously taught to the robot 1, and corrects the horizontal position and orientation of the hand 6 when it reaches hand position 6B based on the comparison result when the robot 1 performs operation M13. Specifically, when the robot 1 performs operation M13, the control unit 32 controls the arm drive mechanism 27, the rotation mechanism 29, and the horizontal movement mechanism 31 based on the position data D1 to D3 to correct the horizontal position and orientation of the hand 6 when it reaches hand position 6B.

[0100] Similarly, in the embodiment described above, the control unit 32 may acquire position data D4 and D5 when the robot 1 performs operation M21, acquire position data D6 when the robot 1 performs operation M22, and correct the horizontal position and orientation of the hand 7 when it reaches hand position 7B based on the position data D4 to D6 when the robot 1 performs operation M23. In this case, after the robot 1 performs operation M21, when the robot 1 loads the substrate 2 placed in the storage cassette 3 onto the hand 7, the arm 9 is extended so that the hand 7 is positioned at the pre-taught hand position 7A. The substrate 2 loaded onto the hand 7 is in the same state (position and orientation) as it was placed in the storage cassette 3.

[0101] In this case, the control unit 32 identifies the front-rear and left-right positions and orientation of the substrate 2 placed on the hand 7 based on the position data D4 to D6, compares the identified front-rear and left-right positions (horizontal position) and orientation of the substrate 2 with the horizontal position and orientation of the substrate 2 previously taught to the robot 1, and corrects the horizontal position and orientation of the hand 7 when it reaches hand position 7B based on the comparison result when the robot 1 performs operation M23. Specifically, when the robot 1 performs operation M23, the control unit 32 controls the arm drive mechanism 28, the rotation mechanism 29, and the horizontal movement mechanism 31 based on the position data D4 to D6 to correct the horizontal position and orientation of the hand 7 when it reaches hand position 7B.

[0102] In this modified example, the storage cassette 3 is a receiving section, and the hand positions 6A and 7A are receiving positions. Furthermore, operations M11 and M21 are first operations, operations M12 and M22 are second operations, and operations M13 and M23 are third operations. Furthermore, in this modified example, the front-to-back direction (X direction) is a first direction that is the direction of movement of the hands 6 and 7 when the robot 1 performs operations M11 and M21, which are the first operations, and the left-to-right direction (X direction) is a second direction that is perpendicular to the up-down direction and the first direction. When the robot 1 performs operations M11, M12, M21, and M22, the two detection mechanisms 33 attached to the hand 6 and the two detection mechanisms 33 attached to the hand 7 are spaced apart in the left-to-right direction.

[0103] In this modified example, even though it is possible to correct the horizontal position and orientation of the substrate 2 placed in the storage cassette 3 before placing the substrate 2 in the processing device 5, it is possible to shorten the transport time of the substrate 2 from the storage cassette 3 to the processing device 5.

[0104] (Other embodiments) The above-described embodiment and modified examples are examples of preferred embodiments of the present invention, but the present invention is not limited to these and various modifications can be made within the scope of the present invention.

[0105] In the above-described embodiment, the robot 1 may transport the substrate 2 from the processing device 5 to the storage cassette 4. That is, the robot 1 may unload the substrate 2 from the processing device 5 and load the substrate 2 unloaded from the processing device 5 into the storage cassette 4. In this case, the processing device 5 serves as a receiving unit, and the storage cassette 4 serves as a delivering unit. Also, in a modified example of the robot control method described above, the robot 1 may transport the substrate 2 from the processing device 5 to the storage cassette 3. In this case, the processing device 5 serves as a receiving unit, and the storage cassette 3 serves as a delivering unit.

[0106] In the above-described embodiment, the robot 1 may be equipped with only one detection mechanism 34. In this case, the detection mechanism 34 is arranged so that when the robot 1 performs operation M12, the right end surface of the board 2 mounted on the hand 6 passes between the light-emitting unit 39 and the light-receiving unit 40 of one detection mechanism 34, and when the robot 1 performs operation M22, the right end surface of the board 2 mounted on the hand 7 passes between the light-emitting unit 39 and the light-receiving unit 40 of one detection mechanism 34. Furthermore, the detection mechanism 34 is arranged so that when the robot 1 performs operation M15, the rear end surface of the board 2 mounted on the hand 6 passes between the light-emitting unit 39 and the light-receiving unit 40 of one detection mechanism 34, and when the robot 1 performs operation M25, the right end surface of the board 2 mounted on the hand 7 passes between the light-emitting unit 39 and the light-receiving unit 40 of one detection mechanism 34.

[0107] In this case, when the robot 1 performs operations M12 and M15, the arm 9 is extended or retracted with the substrate 2 not being loaded on the hand 7, and when the robot 1 performs operations M22 and M25, the arm 8 is extended or retracted with the substrate 2 not being loaded on the hand 6.

[0108] In the above-described embodiment, the light receiving unit 40 may be an area sensor in which a plurality of light receiving elements are arranged two-dimensionally. Even in this case, the detection mechanism 34 can detect the left-right position of the right end surface of the substrate 2 placed on the hands 6 and 7, and the detection mechanism 34 can detect the front-rear position of the rear end surface of the substrate 2 placed on the hands 6 and 7.

[0109] In the embodiment described above, the arms 8 and 9 are arranged offset in the vertical direction, but the arms 8 and 9 may be arranged at the same position in the vertical direction and adjacent to each other in the horizontal direction. Also, in the embodiment described above, the robot 1 may be equipped with only one hand and one arm. For example, the robot 1 may be equipped with only one hand 6 and one arm 8. Also, in the embodiment described above, the arms 8 and 9 may be configured with three or more arm units.

[0110] In the above-described embodiment, instead of arms 8 and 9, robot 1 may be provided with an arm composed of two tip arm sections to which two hands 6 and 7 are rotatably connected at their tip ends, and a common arm section to which the base ends of the two tip arm sections are rotatably connected, such as the arm of the industrial robot disclosed in JP 2018-15839 A.

[0111] Furthermore, in the above-described embodiment, instead of the arms 8 and 9, the robot 1 may be provided with an elongated, approximately rectangular parallelepiped arm that holds the hands 6 and 7 so that the hands 6 and 7 can move linearly back and forth horizontally, like the arm of the industrial robot disclosed in JP 2019-25585 A. In other words, the robot 1 may be a so-called linear type robot in which the hands 6 and 7 are connected to an arm so that they can slide horizontally. Furthermore, in the above-described embodiment, the object to be transported by the robot 1 may be something other than the substrate 2. [Explanation of symbols]

[0112] 1. Robots (industrial robots) 2. Substrates (glass substrates, transported objects) 3, 4 Storage cassette (receiving section) 5 Processing equipment (delivery section) 6, 7 hands 8, 9 Arms 10 Main body 21 First arm section (arm section) 22 Second arm section (arm section) 27, 28 Arm drive mechanism 29 Rotating mechanism 31 Horizontal movement mechanism 32 Control section 33 Detection mechanism (first detection mechanism) 34 Detection mechanism (second detection mechanism) 37 Light-emitting unit (first light-emitting unit) 38 Light receiving unit (first light receiving unit) 39 Light-emitting unit (second light-emitting unit) 40 Light receiving unit (second light receiving unit) X Anteroposterior direction Y left / right direction

Claims

1. An industrial robot that transports a rectangular or square-shaped object, The industrial robot includes a hand on which the transport object is placed and which is movable in a horizontal direction, an arm to which the hand is connected, a main body to which the arm is connected so as to be rotatable with the vertical direction as the axis of rotation, two optical first detection mechanisms attached to the hand, a second optical detection mechanism attached to the main body, and a control unit that controls the industrial robot, The position of the hand when the tip of the hand moves in a direction away from the main body and the hand loads and receives the transport object placed on a predetermined receiving section is defined as a receiving position, and the position of the hand when the tip of the hand moves in a direction away from the main body and the hand delivers the transport object loaded on the hand to a predetermined delivery section is defined as a delivery position. a first action which is an action of the hand moving to the receiving position so that the tip of the hand moves away from the main body; a second action which is an action of the hand receiving the transport object at the receiving position after the first action, moving so that the tip of the hand approaches the main body; and a third action which is an action of the hand with the transport object loaded thereon moving to the delivery position so that the tip of the hand moves away from the main body after the second action, the hand moves linearly while facing a fixed direction relative to the main body when the industrial robot performs the first operation and the second operation; When the industrial robot performs the first operation and the second operation, the moving direction of the hand is defined as a first direction, and a direction perpendicular to the first direction and the up-down direction is defined as a second direction. the first detection mechanism is a reflective detection mechanism including a first light-emitting unit and a first light-receiving unit that receives light emitted from the first light-emitting unit and reflected by the transport object, the two first detection mechanisms are arranged at an interval in the second direction; the second detection mechanism is a transmission-type detection mechanism having a second light-receiving unit formed of a line sensor or an area sensor, and a second light-emitting unit disposed opposite the second light-receiving unit with a predetermined gap between the second light-receiving unit and the second light-emitting unit in the vertical direction, when the industrial robot performs the first operation, the two first detection mechanisms pass under the object placed on the receiving section, when the industrial robot performs the second operation, one end surface of the object to be transported mounted on the hand in the second direction passes between the second light receiving unit and the second light emitting unit, the control unit acquires, when the industrial robot performs the first operation, first position data which is data on the position of the hand in the first direction when one of the two first detection mechanisms detects the transported object, and second position data which is data on the position of the hand in the first direction when the other of the two first detection mechanisms detects the transported object; and, when the industrial robot performs the second operation, acquires third position data which is data on the position in the second direction of one end face of the transported object in the second direction detected by the second detection mechanism when the hand moves to a predetermined measurement position; and, when the industrial robot performs the third operation, corrects the horizontal position and orientation of the hand when it reaches the delivery position based on the first position data, the second position data, and the third position data.

2. The arm is composed of a plurality of arm portions that are rotatably connected to each other and is extendable and contractible in the horizontal direction. the hand is rotatably connected to the tip end of the arm, 2. The industrial robot according to claim 1, wherein a base end of the arm is rotatably connected to the main body.

3. an arm drive mechanism that extends and retracts the arm so that the hand moves linearly with respect to the main body while facing in a fixed direction; a rotation mechanism that rotates the main body; and a horizontal movement mechanism that moves the main body in a left-right direction perpendicular to the up-down direction, When the industrial robot performs the third operation, the hand moves linearly relative to the main body in a front-rear direction perpendicular to the up-down direction and the left-right direction, 3. The industrial robot according to claim 2, wherein, when the industrial robot performs the third operation, the control unit controls the arm drive mechanism, the rotation mechanism, and the horizontal movement mechanism based on the first position data, the second position data, and the third position data to correct the horizontal position and orientation of the hand when the industrial robot reaches the transfer position.

4. the first direction coincides with the left-right direction, 4. The industrial robot according to claim 3, wherein the hand moves linearly in the left-right direction relative to the main body when the industrial robot performs the first operation and the second operation.

5. The first direction coincides with a front-rear direction, 4. The industrial robot according to claim 3, wherein the hand moves linearly in a front-to-rear direction relative to the main body when the industrial robot performs the first operation and the second operation.

6. The transport device includes a hand on which a rectangular or square object to be transported is placed and which is movable in a horizontal direction, an arm to which the hand is connected, a main body to which the arm is connected so as to be rotatable with the vertical direction as the axis of rotation, two first optical detection mechanisms attached to the hand, and a second optical detection mechanism attached to the main body, The position of the hand when the tip of the hand moves in a direction away from the main body and the hand loads and receives the transport object placed on a predetermined receiving section is defined as a receiving position, and the position of the hand when the tip of the hand moves in a direction away from the main body and the hand delivers the transport object loaded on the hand to a predetermined delivery section is defined as a delivery position. a first action which is an action of the hand moving to the receiving position so that the tip of the hand moves away from the main body; a second action which is an action of the hand receiving the transport object at the receiving position after the first action, moving so that the tip of the hand approaches the main body; and a third action which is an action of the hand with the transport object loaded thereon moving to the delivery position so that the tip of the hand moves away from the main body after the second action, the hand moves linearly while facing a fixed direction relative to the main body when the first operation and the second operation are performed; When the moving direction of the hand when the first operation and the second operation are performed is defined as a first direction, and a direction perpendicular to the first direction and the up-down direction is defined as a second direction, the first detection mechanism is a reflective detection mechanism including a first light-emitting unit and a first light-receiving unit that receives light emitted from the first light-emitting unit and reflected by the transport object, the two first detection mechanisms are arranged at an interval in the second direction; the second detection mechanism is a transmission-type detection mechanism having a second light-receiving unit formed of a line sensor or an area sensor, and a second light-emitting unit disposed opposite the second light-receiving unit with a predetermined gap between the second light-receiving unit and the second light-emitting unit in the vertical direction, When the first operation is performed, the two first detection mechanisms pass under the object placed in the receiving section, a control method for an industrial robot, wherein, when the second operation is performed, one end face in the second direction of the object to be transported, which is mounted on the hand, passes between the second light receiving unit and the second light emitting unit, a control method for an industrial robot, characterized in that, when performing the first operation, first position data is acquired which is data on the position of the hand in the first direction when one of the two first detection mechanisms detects the transported object, and second position data is data on the position of the hand in the first direction when the other of the two first detection mechanisms detects the transported object; when performing the second operation, third position data is acquired which is data on the position in the second direction of one end face of the transported object in the second direction detected by the second detection mechanism when the hand moves to a predetermined measurement position; and when performing the third operation, correcting the horizontal position and orientation of the hand when it reaches the delivery position based on the first position data, the second position data, and the third position data.

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