Teaching system for a transport robot, and teaching method for a transport robot.

Abstract

This provides a teaching system for transport robots that is suitable for performing teaching tasks efficiently. [Solution] The transport robot A1 comprises a vertical articulated vertical arm mechanism 1, a rotating member that rotates around an axis extending in the x direction, a horizontal articulated horizontal arm mechanism 3 supported by the rotating member, and a hand section 4 supported by the horizontal arm mechanism 3 and equipped with a detection sensor 5. The hand section 4 has a pair of holding sections 42 that are separated from each other. The detection sensor 5 has a light-emitting section 51 provided on one of the holding sections 42 and a light-receiving section 52 provided on the other holding section 42. The control device 6 positions the hand section 4 so that the optical axis Op of the detection sensor 5 is aligned with the vertical z direction and moves it in the horizontal y direction, and adjusts the position of the hand section 4 in the y direction based on a first position when the target 9 is detected by the detection sensor 5 and a second position when the target 9 is no longer detected by the detection sensor 5.

Description

Technical Field

[0001] The present disclosure relates to a teaching system for a transfer robot and a teaching method for a transfer robot.

Background Art

[0002] In the manufacturing process of semiconductor substrates, liquid crystal substrates, etc., a plurality of substrates are stored in multiple stages in a substrate transfer container called a cassette, and the cassette is transferred to a process device or an inspection device to perform a process treatment or an inspection treatment on the substrates in the cassette. In the process device and the inspection device, a transfer robot is used as an industrial robot for storing substrates in the transferred cassette or taking out substrates from the cassette. The operations for the transfer robot to store substrates in the cassette or take out substrates from the cassette need to be taught in advance by an operator through a teaching operation.

[0003] There is a problem that this teaching operation takes a lot of time. The slots for storing each substrate in the cassette are very narrow and there is not much extra space. In addition, the inside of the cassette may not be visible from outside the opening surface. In this case, since the transfer robot is located in front of the opening surface, the inside of the cassette is very difficult to see. The operator needs to teach the operation of inserting and removing the substrate into and out of this narrow slot manually, relying on their eyes and intuition, by operating the transfer robot.

[0004] Patent Document 1 discloses a configuration in which a protruding portion provided on a jig is detected by an object detection sensor provided on a hand, and teaching is performed based on this detection result. According to such a configuration, manual teaching by an operator is unnecessary, and the time required for the teaching operation can be shortened. However, depending on the configuration of the transfer robot, it has been difficult to perform the teaching operation efficiently with the teaching method described in Patent Document 1.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2015-153809 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] This disclosure was conceived under these circumstances, and its primary objective is to provide a teaching system for a transport robot that is suitable for efficiently performing teaching tasks. [Means for solving the problem]

[0007] To address the above challenges, this disclosure employs the following technical measures.

[0008] A teaching system for a transport robot provided by a first aspect of this disclosure comprises: a transport robot having: a vertical articulated vertical arm mechanism that moves along an in-plane direction orthogonal to a first horizontal direction; a first pivot member that is rotatably supported around a first pivot axis extending in the first direction relative to the vertical arm mechanism; a horizontal articulated horizontal arm mechanism supported by the first pivot member; and a hand portion supported by the horizontal arm mechanism and equipped with an object detection sensor; and a control device that detects a detection target with the object detection sensor while moving the hand portion and teaches the position of the hand portion using the detection result. The hand portion has a base supported by the horizontal arm mechanism and a pair of holding portions extending from the base and separated from each other, the object detection sensor has a light-emitting portion provided on one of the pair of holding portions and a light-receiving portion provided on the other of the pair of holding portions and receiving light emitted from the light-emitting portion, the control device positions the hand portion so that the optical axis of the object detection sensor is aligned with a vertical second direction perpendicular to the first direction, and moves it in a horizontal third direction perpendicular to the first and second directions, and adjusts the position of the hand portion in the third direction based on a first position when the object detection sensor detects the detection target.

[0009] In a preferred embodiment, the control device positions the hand portion along the second direction and moves it in the third direction, and adjusts the position of the hand portion in the third direction based on the second position at which the object detection sensor no longer detects the detection target after passing the first position, and the first position.

[0010] In a preferred embodiment, the control device positions the hand portion so that the optical axis of the object detection sensor is aligned with the third direction and moves it in the second direction, and adjusts the position of the hand portion in the second direction based on the third position when the detection target is detected by the object detection sensor and the fourth position when the detection target is no longer detected by the object detection sensor.

[0011] In a preferred embodiment, the control device positions the hand portion so that the optical axis of the object detection sensor is aligned with the third direction and moves it in the first direction, and adjusts the position of the hand portion in the first direction based on the fifth position when the object detection sensor detects the detection target and the sixth position when the object detection sensor no longer detects the detection target.

[0012] A method for teaching a transport robot provided by a second aspect of the present disclosure comprises: a vertical articulated vertical arm mechanism that moves along an in-plane direction perpendicular to a horizontal first direction; a first pivot member that is rotatably supported around a first pivot axis extending in the first direction relative to the vertical arm mechanism; a horizontal articulated horizontal arm mechanism supported by the first pivot member; and a hand portion supported by the horizontal arm mechanism and equipped with an object detection sensor, wherein the hand portion is moved while a detection target is detected by the object detection sensor, and the position of the hand portion is taught using the detection result, the method for teaching a transport robot, the first aspect of the present disclosure The hand portion has a base supported by the horizontal arm mechanism and a pair of holding portions each extending from the base and separated from each other, and the object detection sensor has a light-emitting portion provided on one of the pair of holding portions and a light-receiving portion provided on the other of the pair of holding portions and receiving light emitted from the light-emitting portion, and the hand portion is positioned so that the optical axis of the object detection sensor is along a vertical second direction perpendicular to the first direction, and is moved in a horizontal third direction perpendicular to the first and second directions, and the position of the hand portion in the third direction is adjusted based on a first position when the object detection sensor detects the detection target.

[0013] In a preferred embodiment, in the step of adjusting the position of the hand portion in the third direction, the hand portion is positioned along the second direction and moved in the third direction, and the position of the hand portion in the third direction is adjusted based on the second position at which the object detection sensor no longer detects the detection target after passing the first position, and the first position.

[0014] In a preferred embodiment, the hand portion is positioned such that the optical axis of the object detection sensor is aligned with the third direction, and is moved in the second direction, and the position of the hand portion in the second direction is adjusted based on the third position when the object detection sensor detects the detection target and the fourth position when the object detection sensor no longer detects the detection target.

[0015] In a preferred embodiment, the hand portion is positioned such that the optical axis of the object detection sensor is aligned with the third direction, and is moved in the first direction, and the position of the hand portion in the first direction is adjusted based on a fifth position when the object detection sensor detects the detection target and a sixth position when the object detection sensor no longer detects the detection target. [Effects of the Invention]

[0016] According to the teaching system for a transport robot described herein, in a transport robot having a configuration that includes a vertical arm mechanism, a first rotating member, a horizontal arm mechanism, and a hand section equipped with an object detection sensor, it is possible to appropriately adjust the position of the hand section in a third direction by making the hand section assume a special posture different from the normal posture for transporting a workpiece.

[0017] Other features and advantages of this disclosure will become more apparent from the detailed description below, with reference to the accompanying drawings. [Brief explanation of the drawing]

[0018] [Figure 1] This is a front view showing an example of a transport robot that constitutes the teaching system for the transport robot related to this disclosure. [Figure 2] Figure 1 is a perspective view of the transport robot. [Figure 3] This is a schematic perspective view showing an example of a cassette for storing workpieces in multiple layers. [Figure 4] Figure 2 is a perspective view showing the state in which the orientation of the horizontal arm mechanism of the transport robot has been changed by rotating the first rotating member. [Figure 5] Figure 4 is a perspective view showing the second horizontal arm of the transport robot rotated to change the orientation of the hand unit. [Figure 6] This is a block diagram showing the control of a transport robot. [Figure 7]It is a flowchart for explaining the teaching process. [Figure 8] It is a side view showing the positional relationship between the detection target and the hand part. [Figure 9] It is a diagram for explaining the first example of the y-direction adjustment process. [Figure 10] It is a perspective view showing the positional relationship between the detection target and the hand part. [Figure 11] It is a diagram for explaining the z-direction adjustment process. [Figure 12] It is a diagram for explaining the x-direction adjustment process. [Figure 13] It is a diagram for explaining the second example of the y-direction adjustment process. [Figure 14] It is a diagram for explaining the second example of the y-direction adjustment process.

Embodiments for Carrying Out the Invention

[0019] Hereinafter, preferred embodiments of the present disclosure will be specifically described with reference to the drawings.

[0020] Terms such as "first", "second", etc. in the present disclosure are merely used as labels and do not necessarily intend to assign an order to those objects.

[0021] Figure 1 is a front view showing an example of a transport robot that constitutes the teaching system for a transport robot according to this disclosure. The transport robot A1 shown in Figure 1 is used, for example, incorporated into an automated substrate transport device called an EFEM (Equipment Front End Module). The transport robot A1 performs tasks such as taking thin, plate-shaped substrates (hereinafter referred to as "workpieces"), such as circular silicon wafers, stored in multiple layers in a cassette 8 (see Figure 3) placed on a load port, and transporting them to a load lock chamber located on the opposite side of the cassette, or discharging workpieces that have finished processing in the processing chamber via the load lock chamber and returning them to the cassette. In this embodiment, the teaching system for a transport robot includes a control device 6 and an input unit 72 in addition to the transport robot A1 (see Figure 6).

[0022] The transport robot A1 comprises a vertical arm mechanism 1, a first rotating member 2, a horizontal arm mechanism 3, a hand unit 4, and a drive mechanism 71 (see Figures 1, 2, and 6).

[0023] In the example illustrated in this embodiment, the x-direction corresponds to the "first direction" of this disclosure, and the y-direction corresponds to the "third direction" of this disclosure. The x-direction and the y-direction are orthogonal to each other and both are directions along the horizontal plane. The z-direction is a direction orthogonal to the x-direction and the y-direction, and corresponds to the vertical direction when the transport robot A1 is placed in a predetermined transport chamber (not shown), etc., and corresponds to the "second direction" of this disclosure. In the following description, the upper side of the z-direction will be appropriately referred to as the "z1 side of the z-direction," and the lower side of the z-direction will be appropriately referred to as the "z2 side of the z-direction." Also, one side of the x-direction will be appropriately referred to as the "x1 side of the x-direction," and the other side of the x-direction will be appropriately referred to as the "x2 side of the x-direction." One side of the y-direction will be appropriately referred to as the "y1 side of the y-direction," and the other side of the y-direction will be appropriately referred to as the "y2 side of the y-direction." Furthermore, in this disclosure, "a surface A facing direction B (either one or the other)" is not limited to the case where the angle of surface A with respect to direction B is 90°, but also includes the case where surface A is inclined with respect to direction B.

[0024] The vertical arm mechanism 1 is a vertical articulated arm mechanism that moves along an in-plane direction perpendicular to the horizontal x-direction, and is composed of, for example, a plurality of rotatably connected arms. In the illustrated example, the vertical arm mechanism 1 comprises a first vertical arm 11 and a second vertical arm 12. The first vertical arm 11 extends in the plane formed by the y-direction and z-direction and is supported by a fixed base 10. Specifically, the base end of the first vertical arm 11 is rotatably supported around a first horizontal axis O1 extending in the x-direction relative to the fixed base 10. The second vertical arm 12 extends in the plane formed by the y-direction and z-direction and is supported by the first vertical arm 11. Specifically, the base end of the second vertical arm 12 is rotatably supported around a second horizontal axis O2 extending in the x-direction at the tip of the first vertical arm 11. Note that the configuration of the vertical arm mechanism 1 is not limited to the illustrated example.

[0025] The first rotating member 2 is supported by the second vertical arm 12 (vertical arm mechanism 1). Specifically, the first rotating member 2 is supported at the tip of the second vertical arm 12 so as to be rotatable around the first rotation axis Ox which extends in the x direction.

[0026] Although detailed illustrations are omitted, the first vertical arm 11 and the second vertical arm 12 are rotated around the first horizontal axis O1 and the second horizontal axis O2, respectively, by using a motor as the drive source and a power transmission means (drive mechanism) such as a belt mechanism or a reduction gear. By controlling the drive of the motor, the horizontal arm mechanism 3, which is supported by the vertical arm mechanism 1 via the first rotating member 2, can be moved to the front of the cassette or load lock chamber. The first rotating member 2 is also rotated as appropriate around the first rotating axis Ox by a drive mechanism (not shown). As a result, the horizontal arm mechanism 3 (the first horizontal arm 31 and the second horizontal arm 32 described later), which is supported by the first rotating member 2, can maintain a horizontal position.

[0027] The horizontal arm mechanism 3 is supported by the first rotating member 2 and is a horizontal articulated arm mechanism that moves along a horizontal plane perpendicular to the z-direction (vertical direction). The horizontal arm mechanism 3 is composed of, for example, a plurality of rotatably connected arms. In the illustrated example, the horizontal arm mechanism 3 includes a first horizontal arm 31 and a second horizontal arm 32. When transporting a workpiece, the first horizontal arm 31 is supported so that its base end is rotatably supported around a first vertical axis V1 that extends in the z-direction relative to the first rotating member 2. The second horizontal arm 32 is supported so that its base end is rotatably supported around a second vertical axis V2 that extends in the z-direction at the tip of the first horizontal arm 31. In this embodiment, the second horizontal arm 32 includes two second horizontal arms 32A and 32B arranged in two upper and lower stages. Note that the configuration of the horizontal arm mechanism 3 is not limited to the illustrated example.

[0028] Although a detailed illustration is omitted, the first horizontal arm 31 and the second horizontal arm 32 can be rotated around the first vertical axis V1 and the second vertical axis V2 by using a motor as the drive source and a power transmission means (drive mechanism) such as a belt mechanism or a reduction gear. When transporting a workpiece, the motor can be driven and controlled to move the hand section 4 (hand section 4A, 4B), which will be described later and supported by the second horizontal arm 32 (second horizontal arm 32A, 32B), in a straight line along the horizontal x-direction.

[0029] The hand section 4 is supported by the second horizontal arm 32 (horizontal arm mechanism 3). Specifically, the hand section 4 is attached to the second horizontal arm 32. In this embodiment, the hand section 4 comprises two hand sections 4A and 4B arranged in two upper and lower stages, and these hand sections 4A and 4B are individually attached to the two second horizontal arms 32A and 32B.

[0030] The hand portion 4 (hand portion 4A, 4B) is a plate member having a base portion 41 connected to the second horizontal arm 32 (second horizontal arm 32A, 32B), and a pair of holding portions 42 extending from the base portion 41. In the hand portion 4 in the posture shown in Figure 10, the pair of holding portions 42 each extend in the x direction and are separated in the y direction. A thin plate-shaped substrate (not shown) is supported by this hand portion 4. Note that the configuration of the hand portion 4 is not limited to the illustrated example.

[0031] The transport robot A1 supports the workpiece while holding the hand unit 4 horizontally, and in this state, moves the hand unit 4 up and down, rotates and moves in the x and y planes, etc., to place the workpiece in the slot 81 in the cassette 8 shown in Figure 3 (storage of workpiece in cassette 8), or to receive the workpiece placed in the slot 81 with the hand unit 4 and take it out of cassette 8 (removal of workpiece from cassette 8).

[0032] An object detection sensor 5 is provided at the tip of the holding portion 42 of the hand portion 4. Details of the object detection sensor 5 will be described later.

[0033] Cassette 8 is a rectangular box-shaped body, with at least one side facing the transport robot A1 being open for loading and unloading workpieces. Multiple slots 81 for storing workpieces in multiple stages are provided protruding inward from both sides of the inside of Cassette 8. Workpieces are placed on the upper surface of a pair of slots 81 at the same height, thereby being stored in the stage corresponding to that height. The gap between opposing pairs of slots 81 inside Cassette 8 is set to be longer than the lateral length of the hand unit 4 (width of the hand unit 4) in order to allow the hand unit 4 to move up and down inside Cassette 8 without interfering with the slots 81.

[0034] The object detection sensor 5 may be, for example, a fiber optic sensor, which is a type of optical sensor. The fiber optic sensor comprises a light-emitting unit 51 and a light-receiving unit 52 that receives light emitted from the light-emitting unit 51. The sensor detects whether or not there is an object between the light-emitting unit 51 and the light-receiving unit 52 by determining whether or not the light-receiving unit 52 receives light from the light-emitting unit 51. In a fiber optic sensor, the light emitted from the light-emitting unit 51 is, for example, red light (visible light). Of course, the object detection sensor 5 is not limited to a fiber optic sensor; any sensor that can detect whether or not the light-receiving unit 52 receives light from the light-emitting unit 51 is acceptable. Also, the light emitted from the light-emitting unit 51 is not limited to visible light; it may be infrared light, etc. In the following explanation, the object detection sensor 5 will be described as a fiber optic sensor. As shown in Figures 5, 8, and 10, the light-emitting part 51 of the object detection sensor 5 is provided at the tip of one holding part 42 of the hand part 4, and the light-receiving part 52 of the object detection sensor 5 is provided at the tip of the other holding part 42.

[0035] The object detection sensor 5 is provided to detect which slot 81 of the cassette 8 the workpiece is placed in. Specifically, the transport robot A1 moves the hand unit 4 in the vertical direction (z-direction as shown in Figures 3 and 9) while emitting light from the light-emitting unit 51 of the object detection sensor 5 toward the light-receiving unit 52. At this time, the hand unit 4 is moved in such a way that the edge of the workpiece can block the optical axis of the object detection sensor 5, and the hand unit 4 does not come into contact with the workpiece. If no workpiece is placed in a slot 81, the light-receiving unit 52 receives the light from the light-emitting unit 51. If a workpiece is placed in a slot 81, the light emitted by the light-emitting unit 51 is blocked by the workpiece, so the light-receiving unit 52 does not receive the light. Therefore, it is possible to detect which slot 81 the workpiece is placed in based on the detection result of the object detection sensor 5. Note that if there is nothing between the light-emitting unit 51 and the light-receiving unit 52, the optical axis of the object detection sensor 5 is not blocked. In this state, the light receiving unit 52 receives light from the light emitting unit 51, which is the "on" state. When the optical axis of the object detection sensor 5 is not obstructed, the amount of light received by the light receiving unit 52 (light intensity) is at its maximum. On the other hand, when there is something obstructing the optical axis between the light emitting unit 51 and the light receiving unit 52 (for example, the edge of the workpiece), as described above, the light receiving unit 52 does not receive light from the light emitting unit 51, which is the "off" state. The same applies to this "on" state and "off" state in the following explanation.

[0036] The control device 6 controls the operation of the vertical arm mechanism 1, the first rotating member 2, and the horizontal arm mechanism 3, and also teaches the position of the hand unit 4. As shown in Figure 6, the control device 6 comprises a control unit 61 and a storage unit 62. The control unit 61 controls the driving of the drive mechanism 71 based on the teaching information stored in the storage unit 62. The drive mechanism 71 gives predetermined movements to the vertical arm mechanism 1, the first rotating member 2, and the horizontal arm mechanism 3. The control unit 61 also controls the driving of the drive mechanism 71 based on information input from the input unit 72. The input unit 72 is used by the operator to perform teaching work or manual operations (for example, a teach pendant). Furthermore, the control unit 61 assists in teaching work and performs teaching work automatically based on the teaching process described later. The teaching process will be described later. The storage unit 62 stores teaching information to show the trajectory of the movement of the hand unit 4. Information acquired in advance by the teaching process is recorded in the storage unit 62 and used as teaching information.

[0037] In this embodiment, as shown in Figures 5, 8, and 10, an object detection sensor 5 provided on the hand unit 4 and a detection target 9 are used to perform an automatic teaching operation. In this automatically performed teaching operation, the position of the hand unit 4 is taught so that the hand unit 4 is adjusted to a predetermined position.

[0038] The detection target 9 is provided, for example, on the EFEM. In the illustrated example, the detection target 9 is fixed to a wall surface near the opening and closing door of a load port (hereinafter referred to as "support surface S1" as appropriate). The detection target 9 is roughly rectangular in shape and has a first surface 91, a second surface 92, a third surface 93, a fourth surface 94, a fifth surface 95, a sixth surface 96, and a recess 97. The first surface 91 and the second surface 92 face opposite each other in the y direction and are parallel to each other. The first surface 91 is located at the y1 side end in the y direction and faces the y1 side in the y direction. The second surface 92 is located at the y2 side end in the y direction and faces the y2 side in the y direction. The third surface 93 and the fourth surface 94 face opposite each other in the z direction. The third surface 93 is located at the z1 side end in the z direction and is the top surface facing the z1 side in the z direction. The fourth surface 94 is located at the z2 end in the z direction and is the bottom surface facing the z2 side in the z direction. The fifth surface 95 and the sixth surface 96 face opposite each other in the x direction. The fifth surface 95 is located at the x1 end in the x direction and faces the x1 side in the x direction. The sixth surface 96 faces the x2 side in the x direction. The recess 97 is recessed from the x2 end in the x direction of the detection target 9 toward the x1 side in the x direction. The upper and lower portions of the recess 97 of the detection target 9 are supported and fixed to the support surface S1. The bottom surface of the recess 97 is the sixth surface 96. In this embodiment, the detection target 9 is made of a material that does not transmit light.

[0039] The detection target 9 is manufactured with high dimensional accuracy in each part. The detection target 9 is guaranteed to have an accurate relative position with respect to a pre-set reference position in a three-dimensional spatial coordinate system based on EFEM. This makes it possible to detect the detection target 9 with the object detection sensor 5 and perform teaching processing using the detection result of the detection target 9. Note that the shape of the detection target 9 is not limited to the shape shown in the illustration above.

[0040] Next, the teaching process for automatically performing the teaching task in this embodiment will be described.

[0041] FIG. 7 is a flowchart for explaining the teaching process performed by the control device 6. The control device 6 (control unit 61) starts the teaching process, for example, when an operator instructs to perform the teaching process from the input unit 72. In the teaching operation, the positions in each of the y-direction, z-direction, and x-direction are adjusted. The teaching process includes a y-direction adjustment process (S1), a z-direction adjustment process (S2), and an x-direction adjustment process (S3).

[0042] <First Example of Y-Direction Adjustment Process> Referring to FIGS. 4, 5, 8, and 9, the y-direction adjustment process will be described. First, the first rotating member 2 of the transfer robot A1 shown in FIG. 2 is rotated to change the posture of the horizontal arm mechanism 3 as shown in FIG. 4. FIG. 4 shows a state where the first rotating member 2 is rotated 90° around the first rotation axis Ox from the transfer robot A1 shown in FIG. 2. In the posture shown in FIG. 4, the first vertical axis V1, which is the rotation axis of the first horizontal arm 31, and the second vertical axis V2, which is the rotation axis of the second horizontal arm 32, are each along the horizontal y-direction.

[0043] Next, the second horizontal arm 32 (32A) of the transfer robot A1 shown in FIG. 4 is rotated to change the posture of the hand part 4 (4A). FIGS. 5 and 8 show a state where the second horizontal arm 32A is rotated 90° around the second vertical axis V2 from the transfer robot A1 shown in FIG. 4. In the postures shown in FIGS. 5 and 8, the pair of holding parts 42 of the hand part 4A are separated in the z-direction. And the optical axis Op of the object detection sensor 5 in the hand part 4A is along the z-direction.

[0044] FIG. 9 is a diagram for explaining the first example of the y-direction adjustment process, and is a schematic diagram showing the positional relationship between the optical axis Op of the object detection sensor 5 provided in the hand part 4 and the detection target 9 when viewed along the x-direction from the x1 side in the x-direction to the x2 side in the x-direction. The optical axis Op of the object detection sensor 5 is a straight line connecting the centers of the light projecting part 51 and the light receiving part 52.

[0045] In the y-direction adjustment process, the hand unit 4 is moved to the y2 side of the y-direction while the object detection sensor 5 performs detection. In this process, the x-direction position of the hand unit 4 is set so that the detection target 9 becomes detectable when the hand unit 4 is moved in the y-direction. Here, the hand unit 4 is positioned so that the optical axis Op of the object detection sensor 5 is located on the y1 side of the y-direction relative to the detection target 9. At this time, there is no detection target 9 between the light emitter 51 and the light receiver 52, and the detection by the object detection sensor 5 is "on". When the hand unit 4 is moved to the y2 side of the y-direction, the optical axis Op of the object detection sensor 5 reaches the y1 side end (first surface 91) of the detection target 9, and the optical axis Op is blocked by the detection target 9. At this time, the light receiver 52 no longer receives light from the light emitter 51, and the detection by the object detection sensor 5 switches to "off". The position of the optical axis Op of the object detection sensor 5 when it reaches the y1 end of the detection target 9 in the y direction is defined as optical axis Op1. When the optical axis Op is at position Op1, it is the position of the hand portion 4 when the detection target 9 is detected by the object detection sensor 5, and corresponds to the first position of this disclosure.

[0046] The hand unit 4 is moved further towards the y2 side in the y direction. While the optical axis Op is obstructed by the detection target 9, detection by the object detection sensor 5 remains "off". Moving the hand unit 4 further towards the y2 side in the y direction causes the optical axis Op of the object detection sensor 5 to reach the y2 side end (second surface 92) of the detection target 9. The position of the optical axis Op at the time it reaches the y2 side end in the y direction is denoted as optical axis Op2. When the optical axis Op of the object detection sensor 5 is located beyond the y2 side end (second surface 92) of the detection target 9 and is positioned further towards the y2 side in the y direction than that end, there is no detection target 9 between the light-emitting unit 51 and the light-receiving unit 52, and detection by the object detection sensor 5 becomes "on". The position of the hand unit 4 when the optical axis Op is at the optical axis Op2 position is the position at which the object detection sensor 5 no longer detects the detection target 9, and corresponds to the second position of this disclosure.

[0047] When the hand part 4 is moved to the y2 side in the y direction as described above, the detection by the object detection sensor 5 changes from on → off → on, and the detection of the object detection sensor 5 turns off only when the optical axis Op of the object detection sensor 5 intersects the detection target 9. Based on such a change in the detection of the object detection sensor 5, the positions (y coordinates) in the y direction of the optical axis Op1 and the optical axis Op2 are recorded in the storage unit 62. If the y coordinate of the optical axis Op1 is ya and the y coordinate of the optical axis Op2 is yb, the y coordinate of the center position Cp of the detection target 9 can be expressed as (ya + yb) / 2, and the y coordinate of the center position Cp can be calculated. Then, based on the y coordinate of the center position Cp of the detection target 9, the position of the hand part 4 in the y direction is adjusted. The position of the hand part 4 in the y direction can be adjusted based on the y coordinate of the center position Cp.

[0048] <z-direction adjustment process> Referring to FIGS. 10 and 11, the z-direction adjustment process will be described. First, the first horizontal arm 31 and the second horizontal arm 32 (32A) are appropriately rotated from the transfer robot A1 shown in FIG. 2 to change the posture of the hand part 4 (4A) as shown in FIG. 10. In the posture shown in FIG. 10, the pair of holding parts 42 of the hand part 4A are separated in the y direction, and each of the two holding parts 42 extends to the x1 side in the x direction. And the optical axis Op of the object detection sensor 5 in the hand part 4A is along the y direction.

[0049] FIG. 11 is a diagram for explaining an example of the y-direction adjustment process, and is a schematic diagram showing the positional relationship between the optical axis Op of the object detection sensor 5 provided in the hand part 4 and the detection target 9 when viewed along the x direction from the x1 side in the x direction to the x2 side in the x direction.

[0050] In the z-direction adjustment process, the hand unit 4 is moved to the z2 side of the z-direction while the object detection sensor 5 performs detection. In this process, the x-direction position of the hand unit 4 is set so that the detection target 9 becomes detectable when the hand unit 4 is moved in the z-direction. Specifically, the hand unit 4 is positioned such that the optical axis Op of the object detection sensor 5 is located between the fifth surface 95 and the sixth surface 96 in the x-direction (see Figure 10). Here, the hand unit 4 is positioned such that the optical axis Op of the object detection sensor 5 is located on the z1 side of the z-direction relative to the detection target 9. At this time, there is no detection target 9 between the light-emitting unit 51 and the light-receiving unit 52, and the detection of the object detection sensor 5 is "on". When the hand unit 4 is moved to the z2 side of the z-direction, when the optical axis Op of the object detection sensor 5 reaches the z1 side end (third surface 93) of the detection target 9 in the z-direction, the optical axis Op is blocked by the detection target 9. At this time, the light receiving unit 52 stops receiving light from the light emitting unit 51, and detection by the object detection sensor 5 switches to "off". The position of the optical axis Op of the object detection sensor 5 when the optical axis Op reaches the z1 side end of the z direction of the detection target 9 is defined as optical axis Op3. When the optical axis Op is at the position of optical axis Op3, this is the position of the hand unit 4 when the detection target 9 is detected by the object detection sensor 5, and corresponds to the third position of this disclosure.

[0051] The hand unit 4 is moved further towards the z2 side in the z direction. While the optical axis Op is obstructed by the detection target 9, detection by the object detection sensor 5 remains "off". Moving the hand unit 4 further towards the z2 side in the z direction causes the optical axis Op of the object detection sensor 5 to reach the z2 side end (fourth surface 94) of the detection target 9 in the z direction. The position of the optical axis Op at the time the optical axis Op reaches the z2 side end in the z direction is denoted as optical axis Op4. When the optical axis Op of the object detection sensor 5 is located beyond the z2 side end (fourth surface 94) of the detection target 9 in the z direction and is positioned further towards the z2 side of that end, there is no detection target 9 between the light-emitting unit 51 and the light-receiving unit 52, and detection by the object detection sensor 5 becomes "on". The position of the hand unit 4 when the optical axis Op is at the optical axis Op4 position is the position at which the object detection sensor 5 no longer detects the detection target 9, and corresponds to the fourth position of this disclosure.

[0052] When the hand part 4 is moved to the z2 side in the z direction in this way, the detection by the object detection sensor 5 changes from on → off → on, and the detection of the object detection sensor 5 turns off only when the optical axis Op of the object detection sensor 5 intersects the detection target 9. Based on such a change in the detection of the object detection sensor 5, the positions (z coordinates) in the z direction of the optical axis Op3 and the optical axis Op4 are recorded in the storage unit 62. If the z coordinate of the optical axis Op3 is za and the z coordinate of the optical axis Op4 is zb, the z coordinate of the center position Cp of the detection target 9 can be expressed as (za + zb) / 2, and the z coordinate of the center position Cp can be calculated. Then, based on the z coordinate of the center position Cp of the detection target 9, the position of the hand part 4 in the z direction is adjusted. The position of the hand part 4 in the z direction can be adjusted based on the z coordinate of this center position Cp.

[0053] <x-direction adjustment process> Referring to FIGS. 10 and 12, the x-direction adjustment process will be described. First, similar to the z-direction adjustment process, the hand part 4 (4A) is placed in the posture shown in FIG. 10.

[0054] FIG. 12 is a diagram for explaining an example of the x-direction adjustment process, and is a schematic diagram showing the positional relationship between the optical axis Op of the object detection sensor 5 provided on the hand part 4 and the detection target 9 when viewed along the z direction from the z1 side to the z2 side in the z direction.

[0055] In the x-direction adjustment process, the hand unit 4 is moved to the x2 side in the x-direction while the object detection sensor 5 performs detection. In this process, the position of the hand unit 4 in the z-direction is set so that the detection target 9 becomes detectable when the hand unit 4 is moved in the x-direction. Specifically, the hand unit 4 is positioned so that the optical axis Op of the object detection sensor 5 coincides with the sixth surface 96 when viewed along the x-direction (see Figure 10). Here, the hand unit 4 is positioned so that the optical axis Op of the object detection sensor 5 is located on the x1 side in the x-direction relative to the detection target 9. At this time, there is no detection target 9 between the light emitter 51 and the light receiver 52, and the detection of the object detection sensor 5 is "on". When the hand unit 4 is moved to the x2 side in the x-direction, when the optical axis Op of the object detection sensor 5 reaches the z1 side end (fifth surface 95) in the z-direction of the detection target 9, the optical axis Op is blocked by the detection target 9. At this time, the light receiving unit 52 stops receiving light from the light emitting unit 51, and the detection by the object detection sensor 5 switches to "off". The position of the optical axis Op of the object detection sensor 5 when the optical axis Op reaches the x1 side end in the x direction of the detection target 9 is defined as optical axis Op5. When the optical axis Op is at the position of optical axis Op5, this is the position of the hand unit 4 when the detection target 9 is detected by the object detection sensor 5, and corresponds to the fifth position of this disclosure.

[0056] The hand unit 4 is moved further towards the x2 side in the x direction. While the optical axis Op is blocked by the detection target 9, detection by the object detection sensor 5 remains "off". When the hand unit 4 is moved further towards the x2 side in the x direction, the optical axis Op of the object detection sensor 5 reaches the end face (6th surface 96) on the x2 side in the x direction of the detection target 9. The position of the optical axis Op at the time the optical axis Op reaches the end face (6th surface 96) on the x2 side in the x direction is denoted as optical axis Op6. When the optical axis Op of the object detection sensor 5 goes beyond the end face (6th surface 96) on the x2 side in the x direction of the detection target 9 and is located further towards the x2 side in the x direction than that end face, the optical axis Op passes through the recess 97. At this time, there is no detection target 9 between the light-emitting unit 51 and the light-receiving unit 52, and detection by the object detection sensor 5 becomes "on". This is the position of the hand portion 4 when the optical axis Op is at the position of optical axis Op6, at which the object detection sensor 5 can no longer detect the detection target 9, and corresponds to the sixth position of this disclosure.

[0057] As the hand unit 4 is moved towards the x2 side in the x-direction, the detection by the object detection sensor 5 changes from on → off → on, and the detection by the object detection sensor 5 is turned off only when the optical axis Op of the object detection sensor 5 intersects with the detection target 9. Based on this change in detection by the object detection sensor 5, the x-direction positions (x-coordinates) of the optical axes Op5 and Op6 are recorded in the storage unit 62. If the x-coordinate of optical axis Op5 is xa and the x-coordinate of optical axis Op6 is xb, the x-coordinate of the center position Cp of the detection target 9 can be expressed as (xa + xb) / 2, and the x-coordinate of the center position Cp can be calculated. Then, the position of the hand unit 4 in the x-direction is adjusted based on the x-coordinate of the center position Cp of the detection target 9. The position of the hand unit 4 in the x-direction can be adjusted based on this x-coordinate of the center position Cp.

[0058] Next, the operation of this embodiment will be described.

[0059] According to this embodiment, the teaching process is performed automatically by the control device 6. In this teaching process, the amount of manual work required by the operator is minimal and consists only of simple tasks. Therefore, the time required for the teaching process can be significantly reduced. Furthermore, since an object detection sensor, which is typically installed on the hand of a transport robot, is used, there is no need to install any other equipment on the transport robot.

[0060] The transport robot A1 comprises a vertical arm mechanism 1, a first rotating member 2, and a horizontal arm mechanism 3. An object detection sensor 5 is provided on a hand portion 4 supported by the horizontal arm mechanism 3. While moving the hand portion 4, the object detection sensor 5 detects a detection target 9, and the control device 6 uses this detection result to teach the position of the hand portion 4. The hand portion 4 has a base portion 41 supported by the horizontal arm mechanism 3, and a pair of holding portions 42 that extend from the base portion 41 and are separated from each other. The object detection sensor 5 has a light-emitting portion 51 and a light-receiving portion 52 that receives light emitted from the light-emitting portion 51. The light-emitting portion 51 is provided on one of the holding portions 42, and the light-receiving portion 52 is provided on the other holding portion 42. The control device 6 positions the hand portion 4 so that the optical axis Op of the object detection sensor 5 is aligned with the vertical z direction (second direction), and moves it in the horizontal y direction (third direction). Then, the position of the hand unit 4 in the y-direction is adjusted based on the position when the object detection sensor 5 detects the detection target 9 (first position) and the position when the object detection sensor 5 no longer detects the detection target 9 (second position). With this configuration, by making the hand unit 4 assume a special posture different from the normal posture for transporting a workpiece, it becomes possible to appropriately adjust the position of the hand unit 4 in the y-direction.

[0061] In the present disclosure, different from the above case, the control device 6 sets the hand part 4 to a posture along the z direction (second direction) and moves it in the horizontal y direction (third direction), and may adjust the position of the hand part 4 in the y direction based only on the position (first position) when the detection target 9 is detected by the object detection sensor 5. As described above, the detection target 9 is manufactured with good dimensional accuracy of each part, and an accurate relative positional relationship is guaranteed with respect to a reference position preset in the three-dimensional space coordinate system. Therefore, it is possible to calculate the y coordinate of the center position Cp of the detection target 9 based on the position (first position) when the detection target 9 is detected by the object detection sensor 5, and the position of the hand part 4 in the y direction can be adjusted based on the y coordinate of this center position Cp.

[0062] In the teaching process of the present embodiment, the control device 6 sets the hand part 4 to a posture along the horizontal y direction (third direction) where the optical axis Op of the object detection sensor 5 is horizontal, and moves it in the vertical z direction (second direction). Then, based on the position (third position) when the detection target 9 is detected by the object detection sensor 5 and the position (fourth position) when the detection target 9 is no longer detected by the object detection sensor 5, the position of the hand part 4 in the z direction is adjusted. Further, the control device 6 sets the hand part 4 to a posture along the horizontal y direction (third direction) where the optical axis Op of the object detection sensor 5 is horizontal, and moves it in the horizontal x direction (first direction). Then, based on the position (fifth position) when the detection target 9 is detected by the object detection sensor 5 and the position (sixth position) when the detection target 9 is no longer detected by the object detection sensor 5, the position of the hand part 4 in the x direction is adjusted. According to such a configuration, the adjustment of the position of the hand part 4 in the z direction and the x direction can be efficiently performed.

[0063] <y-direction adjustment process - second example> Figures 13 and 14 illustrate a second example of the y-direction adjustment process. Figure 13 is a longitudinal section of the cassette 8, and Figure 14 is a transverse section of the cassette 8. Figures 13 and 14 show a configuration in which a workpiece W (represented by dashed lines) is supported in a slot 81 of the cassette 8. The workpiece W is, for example, a circular silicon wafer, manufactured with high dimensional accuracy in each part. The workpiece W is guaranteed to have an accurate relative position with respect to a preset reference position in a three-dimensional spatial coordinate system based on EFEM. The workpiece W shown in Figures 13 and 14 serves as the detection target of this disclosure. In the example shown in Figures 13 and 14, a detection target 9A is placed on the bottom wall inside the cassette 8. The detection target 9A has at least a third surface 93, a fourth surface 94, a fifth surface 95, and a sixth surface 96. These third surface 93, fourth surface 94, fifth surface 95, and sixth surface 96 face the same directions as the third surface 93, fourth surface 94, fifth surface 95, and sixth surface 96 of the detection target 9, as explained with reference to Figures 8, 10, etc. In the detection target 9A, the legs 98 are fixed to the bottom wall of the cassette 8, and the sixth surface 96 is separated from the bottom wall on the z1 side in the z direction.

[0064] In the y-direction adjustment process of this example, as shown in Figure 13, the hand unit 4 is positioned so that the optical axis Op of the object detection sensor 5 is aligned with the z-direction. The hand unit 4 is then positioned so that the pair of holding parts 42 enter the cassette 8 from the opening towards the x1 side in the x-direction by a predetermined distance.

[0065] In the y-direction adjustment process of this example, the hand unit 4 is moved to the y2 side of the y-direction while detection is performed by the object detection sensor 5 (see Figure 14). In this process, the x-direction position of the hand unit 4 is set so that the workpiece W (detection target) can be detected when the hand unit 4 is moved in the y-direction. Here, the hand unit 4 is positioned so that the optical axis Op of the object detection sensor 5 is located on the y1 side of the y-direction relative to the workpiece W. At this time, there is no workpiece W between the light emitter 51 and the light receiver 52, and detection by the object detection sensor 5 is "on". When the hand unit 4 is moved to the y2 side of the y-direction, when the optical axis Op of the object detection sensor 5 reaches the y1 side edge of the workpiece W, the optical axis Op is blocked by the workpiece W. At this time, the light receiver 52 no longer receives light from the light emitter 51, and detection by the object detection sensor 5 switches to "off". The position of the optical axis Op of the object detection sensor 5 when the optical axis Op reaches the edge of the workpiece W on the y1 side in the y direction is defined as optical axis Op1. When the optical axis Op is at position Op1, this is the position of the hand portion 4 when the workpiece W (detection target) is detected by the object detection sensor 5, and corresponds to the first position in this disclosure.

[0066] The hand unit 4 is moved further towards the y2 side in the y direction. While the optical axis Op is obstructed by the workpiece W, detection by the object detection sensor 5 remains "off". When the hand unit 4 is moved further towards the y2 side in the y direction, the optical axis Op of the object detection sensor 5 reaches the edge of the workpiece W on the y2 side in the y direction. The position of the optical axis Op at the time the optical axis Op reaches the edge on the y2 side in the y direction is denoted as optical axis Op2. When the optical axis Op of the object detection sensor 5 is located beyond the edge of the workpiece W on the y2 side in the y direction and is positioned further towards the y2 side in the y direction than that edge, there is no workpiece W between the light-emitting unit 51 and the light-receiving unit 52, and detection by the object detection sensor 5 becomes "on". The position of the hand unit 4 when the optical axis Op is at the optical axis Op2 position is when the workpiece W (detection target) is no longer detected by the object detection sensor 5, and corresponds to the second position in this disclosure.

[0067] As the hand unit 4 is moved to the y2 side in the y direction, the detection by the object detection sensor 5 changes from on → off → on, and the detection by the object detection sensor 5 is turned off only when the optical axis Op of the object detection sensor 5 intersects with the workpiece W. Based on this change in detection by the object detection sensor 5, the y-direction positions (y-coordinates) of the optical axes Op1 and Op2 are recorded in the storage unit 62. If the y-coordinate of optical axis Op1 is ya and the y-coordinate of optical axis Op2 is yb, the y-coordinate of the y-direction center position Cy of the workpiece W can be expressed as (ya + yb) / 2, and the y-coordinate of the y-direction center position Cy can be calculated. Then, the y-direction position of the hand unit 4 is adjusted based on the y-coordinate of the y-direction center position Cy of the workpiece W. The y-direction position of the hand unit 4 can be adjusted based on this y-coordinate of the y-direction center position Cy.

[0068] Furthermore, the z-direction adjustment process and the x-direction adjustment process can be performed using the detection target 9A located inside the cassette 8, following the same procedure as described above with reference to Figures 10 to 12.

[0069] In the y-direction adjustment process of the teaching process in this example, the control device 6 positions the hand unit 4 so that the optical axis Op of the object detection sensor 5 is aligned with the vertical z-direction (second direction), and moves it in the horizontal y-direction (third direction). Then, based on the position when the workpiece W (detection target) is detected by the object detection sensor 5 (first position) and the position when the workpiece W is no longer detected by the object detection sensor 5 (second position), the control device 6 adjusts the y-direction position of the hand unit 4. With this configuration, by making the hand unit 4 assume a special posture different from the normal posture for transporting workpieces, it becomes possible to appropriately adjust the y-direction position of the hand unit 4.

[0070] In this disclosure, unlike the above case, the control device 6 may position the hand unit 4 along the z direction (second direction), move it in the horizontal y direction (third direction), and adjust the y-direction position of the hand unit 4 based only on the position (first position) when the workpiece W (detection target) is detected by the object detection sensor 5. As described above, the workpiece W (detection target) is manufactured with good dimensional accuracy in each part, and an accurate relative positional relationship with respect to a preset reference position in the three-dimensional spatial coordinate system is guaranteed. For this reason, it is possible to calculate the y-coordinate of the y-direction center position Cy of the workpiece W (detection target) based on the position (first position) when the workpiece W (detection target) is detected by the object detection sensor 5, and the y-direction position of the hand unit 4 can be adjusted based on the y-coordinate of this y-direction center position Cy.

[0071] The teaching system and teaching method for transport robots relating to this disclosure are not limited to the embodiments described above. The specific configuration of the teaching system and teaching method for transport robots relating to this disclosure can be modified in various ways. [Explanation of Symbols]

[0072] A1: Transport robot, 1: Vertical arm mechanism, 2: First rotating member, 3: Horizontal arm mechanism, 4,4A,4B: Hand section, 41: Base, 42: Holding section 42, 5: Object detection sensor, 51: Light emitter, 52: Light receiver, 6: Control device, 9,9A: Detection target, Op: Optical axis, Ox: First rotating axis

Claims

1. A transport robot comprising: a vertical articulated vertical arm mechanism that moves along an in-plane direction perpendicular to a horizontal first direction; a first pivot member supported so as to be rotatable around a first pivot axis extending in the first direction relative to the vertical arm mechanism; a horizontal articulated horizontal arm mechanism supported by the first pivot member; and a hand portion supported by the horizontal arm mechanism and equipped with an object detection sensor; A teaching system for a transport robot, comprising: a control device that detects a detection target with the object detection sensor while moving the hand portion, and teaches the position of the hand portion using the detection result, The hand portion has a base supported by the horizontal arm mechanism and a pair of holding portions extending from the base and separated from each other. The object detection sensor comprises a light-emitting unit provided on one of the pair of holding units, and a light-receiving unit provided on the other of the pair of holding units for receiving light emitted from the light-emitting unit. A teaching system for a transport robot, wherein the control device positions the hand portion so that the optical axis of the object detection sensor is aligned with a vertical second direction perpendicular to the first direction, and moves it in a horizontal third direction perpendicular to the first and second directions, and adjusts the position of the hand portion in the third direction based on a first position when the detection target is detected by the object detection sensor.

2. The teaching system for a transport robot according to claim 1, wherein the control device positions the hand portion in a orientation along the second direction and moves it in the third direction, and adjusts the position of the hand portion in the third direction based on the second position at which the object detection sensor no longer detects the detection target after passing the first position, and the first position.

3. A teaching method for a transport robot comprising: a vertical articulated vertical arm mechanism that moves along an in-plane direction perpendicular to a horizontal first direction; a first pivot member supported so as to be rotatable about a first pivot axis extending in the first direction relative to the vertical arm mechanism; a horizontal articulated horizontal arm mechanism supported by the first pivot member; and a hand portion supported by the horizontal arm mechanism and equipped with an object detection sensor, wherein the hand portion is moved while a detection target is detected by the object detection sensor, and the position of the hand portion is taught using the detection result, The hand portion has a base supported by the horizontal arm mechanism and a pair of holding portions extending from the base and separated from each other. The object detection sensor comprises a light-emitting unit provided on one of the pair of holding units, and a light-receiving unit provided on the other of the pair of holding units for receiving light emitted from the light-emitting unit. A method for teaching a transport robot, comprising the steps of positioning the hand portion so that the optical axis of the object detection sensor is aligned with a second vertical direction perpendicular to the first direction, and moving it in a third horizontal direction perpendicular to the first and second directions, and adjusting the position of the hand portion in the third direction based on a first position when the object detection sensor detects the detection target.

4. A method for teaching a transport robot according to claim 3, wherein in the step of adjusting the position of the hand portion in the third direction, the hand portion is positioned to be aligned with the second direction and moved in the third direction, and the position of the hand portion in the third direction is adjusted based on the second position at which the object detection sensor no longer detects the detection target after passing the first position, and the first position.

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