Teaching unit

Abstract

This teaching unit enables teaching of an operating position relative to a measurement object in an overhead carrier vehicle. The teaching unit is provided with: a first unit that is installed in a prescribed state on a measurement object; and a second unit which is detachably connected to the first unit, has a measurement part for measuring the position of the first unit, and is vertically-movably held by the overhead carrier vehicle. The first unit has an output device that outputs information indicating the installation state of the first unit relative to the measurement object. The second unit has an acquisition device that acquires information outputted from the output device.

Description

Teaching Unit

[0001] The present disclosure relates to a teaching unit.

[0002] A teaching unit for learning the transfer position of a transported object relative to a transfer unit in an overhead transport vehicle has been known. For example, a teaching unit described in Patent Document 1 includes a teaching plate installed on a load port (transfer unit) and a detection unit that detects the position of the teaching plate. The detection unit is attached to a unit body that is gripped by a lifting unit of the overhead transport vehicle.

[0003] In the teaching unit, three holes into which three pins of the load port are inserted are formed in the plate body of the teaching plate. A contact sensor is provided above the holes so as to cover the openings of the holes from above. The contact sensor is configured to be able to come into contact with the tops of the pins inserted into the holes. When the contact sensor comes into contact with the pins, it sends a detection signal to the control unit of the overhead transport vehicle.

[0004] Japanese Patent Application Laid-Open No. 2021-187563

[0005] In the conventional teaching unit described above, the control unit of the overhead hoist transport vehicle determines whether the teaching plate is placed in the correct position on the load port by checking whether all contact sensors detect the pins. If it determines that the teaching plate is not placed in the correct position on the load port, the control unit of the overhead hoist transport vehicle repeatedly raises and lowers the gripper (lifting unit) (retry). This allows the overhead hoist transport vehicle to place the teaching plate in the correct position on the load port.

[0006] In conventional teaching units, information on whether the teaching plate is placed in the correct position on the load port is transmitted to the control unit of the overhead transport vehicle. This requires a configuration for information communication between the teaching plate and the overhead transport vehicle, and the various controls by the control unit of the overhead transport vehicle can become complicated.

[0007] The present disclosure describes a teaching unit that can recognize within the unit whether or not a first unit has been correctly set on a measurement target without using an overhead transport vehicle.

[0008] [1] One aspect of the present disclosure is a teaching unit for teaching an operating position relative to a measurement target part in an overhead transport vehicle, comprising: a first unit that is installed in a predetermined state on the measurement target part; and a second unit that is detachably connected to the first unit, has a measuring unit that measures the position of the first unit, and is held so that it can be raised and lowered by the overhead transport vehicle, wherein the first unit has an output device that outputs information indicating the installation state of the first unit relative to the measurement target part, and the second unit has an acquisition device that acquires the information output from the output device.

[0009] According to the teaching unit of [1], the acquisition device of the second unit acquires information indicating the installation status of the first unit relative to the measurement target. This allows the second unit to recognize that the first unit is correctly set on the measurement target. Therefore, whether the first unit is correctly set on the measurement target can be recognized within the teaching unit without using the ceiling guided vehicle. When the first unit is correctly set on the measurement target, the amount of positional deviation can be detected based on the relative positional relationship of the second unit with respect to the first unit, allowing teaching to be performed appropriately.

[0010] [2] In the teaching unit of [1] above, the output device may be a display device that turns on the lighting unit when the first unit is installed in a predetermined state on the measurement target, and the acquisition device may detect that the lighting unit has been turned on. In this case, it is possible to easily recognize with a simple configuration whether the first unit is correctly installed on the measurement target.

[0011] [3] In the teaching unit of [1] above, the output device may be a position detection device including a touch panel unit that detects the installation position of the first unit relative to the measurement target, and the acquisition device may acquire the detection results from the position detection device and correct the detection results using the measurement results from the measurement unit. In this case, not only can it be determined whether the first unit is correctly set on the measurement target, but the relative positional relationship of the first unit with respect to the measurement target (detection results from the position detection device) is corrected using the relative positional relationship of the second unit with respect to the first unit (measurement results from the measurement unit). This makes it possible to detect the amount of positional deviation of the second unit with respect to the measurement target, allowing for optimal teaching.

[0012] [4] In any one of the teaching units [1] to [3] above, the second unit may include a bottom plate portion having at least one through hole, and the first unit may include at least one supported portion supported by the bottom plate portion at or near the through hole, a contact plate portion located below the bottom plate portion and including a contact surface that contacts the measurement target portion, and at least one columnar portion connecting the supported portion and the contact plate portion and movable up and down within the through hole. When the second unit descends and the contact plate portion of the first unit is supported by the measurement target portion, the first unit may be separated from the second unit. In this case, when the second unit descends and the first unit is separated from the second unit, support of the supported portion by the bottom plate portion is released, and the columnar portion is inserted into the through hole, allowing some movement of the supported portion relative to the through hole in the horizontal direction. This allows movement of the second unit relative to the first unit in the rotational direction about the vertical axis and in the horizontal direction. As a result, the amount of positional deviation of the second unit relative to the first unit in the rotational direction about the vertical axis and in the horizontal direction can be detected with high accuracy.

[0013] According to the present disclosure, it is possible to recognize within the teaching unit whether or not the first unit has been correctly set on the measurement target portion without using the ceiling transport vehicle.

[0014] FIG. 1 is a side view showing an overhead transport vehicle, a measurement target, and a teaching unit in one embodiment. FIG. 2 is a cross-sectional view showing a teaching unit according to a first embodiment. FIG. 3(a) is a plan view of an upper plate portion of a first unit in FIG. 2, and FIG. 3(b) is a plan view of a bottom plate portion of a second unit in FIG. 2. FIG. 4 is a block diagram showing the functional configuration of an overhead transport vehicle system to which the teaching unit according to the first embodiment is applied. FIG. 5 is a diagram for explaining teaching using the teaching unit according to the first embodiment. FIG. 6 is a cross-sectional view showing a teaching unit according to a second embodiment. FIG. 7 is a block diagram showing the functional configuration of an overhead transport vehicle system to which the teaching unit according to the second embodiment is applied. FIG. 8 is a diagram for explaining teaching using the teaching unit according to the second embodiment.

[0015] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are given the same reference numerals, and duplicated description will be omitted.

[0016] First, an overhead transport vehicle 1 and an overhead transport vehicle system 100 to which a teaching unit 20 according to a first embodiment is applied will be described with reference to Figures 1 and 4. As shown in Figures 1 and 4, the overhead transport vehicle system 100 includes a plurality of overhead transport vehicles 1, at least one teaching unit 20, and an area controller 110.

[0017] As shown in Fig. 1, an overhead transport vehicle 1 travels along a track R laid near the ceiling of a clean room where semiconductor devices are manufactured. The overhead transport vehicle 1 transports a container (transported object) 200, such as a FOUP (Front Opening Unified Pod) containing multiple semiconductor wafers or a reticle pod containing reticles. The overhead transport vehicle 1 transfers the container 200 to a load port (transfer portion, measurement object portion) 300 or the like provided in a processing device that performs various processes on the semiconductor wafers. A flange 223 is provided at the upper end of the container 200 and is held by a pair of grippers 12, 12 of the overhead transport vehicle 1.

[0018] The overhead transport vehicle 1 includes a frame unit 2, a traveling unit 3, a lateral unit 4, a theta unit 5, a lifting drive unit 6, a holding unit 7, and a transport vehicle controller 8. The frame unit 2 has a center frame 15, a front frame 16, and a rear frame 17. The front frame 16 extends downward from the front end of the center frame 15 (the front end in the traveling direction of the overhead transport vehicle 1). The rear frame 17 extends downward from the rear end of the center frame 15 (the rear end in the traveling direction of the overhead transport vehicle 1).

[0019] The propulsion unit 3 is disposed above the center frame 15. The propulsion unit 3 propels along the track R by receiving a contactless supply of power, for example, from a high-frequency current line laid along the extension direction (X direction) of the track R. The lateral unit 4 is disposed below the center frame 15. The lateral unit 4 moves the theta unit 5, the lifting / lowering drive unit 6, and the holding unit 7 laterally, which is perpendicular to the propulsion direction. The theta unit 5 is disposed below the lateral unit 4. The theta unit 5 rotates the lifting / lowering drive unit 6 and the holding unit 7 in a horizontal plane. The lifting / lowering drive unit 6 is disposed below the theta unit 5. The lifting / lowering drive unit 6 raises and lowers the holding unit 7. The holding unit 7 is disposed below the lifting / lowering drive unit 6. The holding unit 7 is suspended from the lifting / lowering drive unit 6 by multiple wires B.

[0020] The holding unit 7 has a base 11 and a pair of grippers 12. The pair of grippers 12 are supported by the base 11 so as to be openable and closable in the Y direction. The pair of grippers 12 are opened and closed by a drive motor (not shown) and a link mechanism (not shown). For example, when the pair of grippers 12 are in an open state, the height position of the holding unit 7 is adjusted so that the holding surfaces of the grippers 12 are lower than the height of the lower surface of the flange 223. When the pair of grippers 12 are closed in this state, the holding surfaces of the grippers 12 advance below the lower surface of the flange 223. When the lifting drive unit 6 is raised in this state, the pair of grippers 12 hold (grasp) the flange 223, and the container 200 is held.

[0021] The transport vehicle controller 8 is disposed on the center frame 15. The transport vehicle controller 8 is an electronic control unit configured with a processor such as a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), etc. The transport vehicle controller 8 controls each part of the overhead transport vehicle 1.

[0022] The transport vehicle controller 8 controls the operation of the ceiling transport vehicle 1 based on preset transfer conditions, and transfers the container 200 to the load port 300. The transfer conditions are control parameters for transferring the container 200 to the load port 300. The transfer conditions may include information regarding the positions of the pair of grippers 12, 12 in the X direction, Y direction, and Z direction when transferring the container 200 to the load port 300, and information regarding the θ direction position, which is the position of the pair of grippers 12, 12 in the rotational direction within a horizontal plane. More specifically, the transfer conditions may include the drive amount (stop position) of the traveling unit 3, the drive amount of the lateral unit 4, the drive amount of the theta unit 5, and the drive amount of the lift drive unit 6 when transferring the container 200 to the load port 300. The transfer conditions are stored in a memory unit (not shown) of the transport vehicle controller 8. The transport vehicle controller 8 also controls the teaching operation when a teaching unit 20, which will be described in detail later, is attached.

[0023] In this embodiment, a distinction is made between the functions (control or processing, etc.) of the transport vehicle controller 8 and the functions (control or processing, etc.) of the teaching unit 20. For example, the teaching unit 20 has functions such as i) imaging and calculating the amount of horizontal deviation, ii) calculating the amount of tilt using laser measurement, iii) determining the descent stop position, iv) determining whether the measurement is complete, v) determining whether the first unit 40 (see FIG. 2) has been successfully installed and reporting this to the transport vehicle controller 8, and vi) indicating whether the first unit 40 has been successfully installed. The above function i) is performed by the camera unit 57 and the teaching control unit 60 (see FIG. 4), and the above function ii) is performed by the distance measurement sensor 58 and the teaching control unit 60. The above function iii) is performed by the deceleration sensor 59 and the teaching control unit 60. Information regarding the timing of the descent stop is transmitted to the transport vehicle controller 8 by the teaching control unit 60. The above functions iv) to vi) are performed by the teaching control unit 60.

[0024] On the other hand, the guided vehicle controller 8 has functions such as vii) lifting and lowering operations such as lowering, raising, and stopping of the teaching unit 20, and operations in various directions by the lateral unit 4 and theta unit 5, etc., viii) recording measurement results transmitted from the teaching unit 20, ix) indicating the teaching mode and subsequent operations, and x) indicating the success or failure of teaching. The above ix) and x) are displayed or notified, for example, by a 7-segment panel or sound. As described above, the teaching unit 20 has functions related to measurement and calculation in teaching. The teaching unit 20 not only measures the position of the first unit 40, but also determines the success or failure of installation of the first unit 40, and the guided vehicle controller 8 receives the measurement results and determination results.

[0025] The area controller 110 is an electronic control unit including a processor such as a CPU, a ROM, a RAM, and the like. The area controller 110 can be configured as software in which a program stored in the ROM is loaded onto the RAM and executed by the CPU, for example. The area controller 110 may also be configured as hardware including electronic circuits, etc. The area controller 110 communicates with multiple ceiling transport vehicles 1 and controls the multiple ceiling transport vehicles 1. That is, the area controller 110 causes the multiple ceiling transport vehicles 1 to execute various commands. For example, the area controller 110 causes the multiple ceiling transport vehicles 1 to execute transport commands.

[0026] In the ceiling transport vehicle system 100 described above, teaching is performed when the ceiling transport vehicle 1 starts transporting the container 200 (before the ceiling transport vehicle system 100 is put into operation) or periodically as part of maintenance. Teaching refers to determining how much the transfer position of the container 200 will deviate from the target position when the container 200 is transferred according to preset transfer conditions, and memorizing the operations that the ceiling transport vehicle 1 should perform to eliminate the deviation from the target position. Examples of the operations that should be performed include the amount of correction for the transfer conditions (information related to teaching), i.e., the drive amount (travel stop position) of the traveling unit 3, the drive amount of the lateral unit 4, the drive amount of the theta unit 5, and the drive amount of the lift drive unit 6.

[0027] Next, the teaching unit 20 according to this embodiment will be described with reference to FIGS. 2 to 4. As shown in FIG. 2, the teaching unit 20 is used for teaching the overhead transport vehicle 1 to indicate a transfer position (operating position) relative to the load port 300. The teaching unit 20 includes a first unit 40 and a second unit 50 that is detachably connected to the first unit 40. The first unit 40 is disposed below the teaching unit 20, and the second unit 50 is disposed above the teaching unit 20. The second unit 50 is held (supported) by the overhead transport vehicle 1 during teaching. The first unit 40 is installed in a predetermined state on the load port 300 during teaching. The upper part of the first unit 40 is connected to the lower part of the second unit 50 in a loosely fitted state. The first unit 40 can move freely relative to the second unit 50 within predetermined ranges in the X, Y, and Z directions (see the connecting portion 43 and through-hole 56 described below).

[0028] In the description of this embodiment, the X direction is the extension direction of the track R and the traveling direction of the overhead transport vehicle 1. The Y direction is the lateral direction (horizontal direction) perpendicular to the traveling direction. In the following description, the use state of the teaching unit 20 when the load port 300 (measurement target) is arranged along the X direction (see FIG. 1) is used as a reference. Since the teaching unit 20 can be rotated horizontally depending on the orientation of the load port 300, in the description of the teaching unit 20, the X direction can be interpreted as "a certain direction in the horizontal direction" and the Y direction can be interpreted as "a direction different from the X direction in the horizontal direction" (and perpendicular to the X direction).

[0029] The second unit 50 is held by the holding unit 7 so as to be freely raised and lowered. The second unit 50 has a main body 51 that forms the main frame of the teaching unit 20. The main body 51 includes a flange 23 at the center of its upper end. The flange 23 is held by grippers 12, 12 (see FIG. 1 ) that are mounted on the holding unit 7 and raised and lowered. The main body 51 includes a top plate 53, a bottom plate 54, and two side wall portions 55. The top plate 53 and the bottom plate 54 are spaced apart in the Z direction and face each other. The top plate 53 extends in the X and Y directions below the flange 23. The bottom plate 54 extends in the X and Y directions below the top plate 53. The pair of side wall portions 55 extend, for example, along the XZ plane. Note that four side wall portions may be provided in the main body 51.

[0030] The first unit 40 is supported on the bottom plate portion 54 of the second unit 50. The first unit 40 has an upper plate portion 41, a contact plate portion 42 extending parallel to the upper plate portion 41, and at least one connecting portion 43. The upper plate portion 41 and the contact plate portion 42 are spaced apart in the Z direction and face each other. The upper plate portion 41 and the contact plate portion 42 extend along the X direction and the Y direction. The upper plate portion 41 is located on an upper surface 54a of the bottom plate portion 54. The contact plate portion 42 is located below the bottom plate portion 54. In other words, the upper plate portion 41, which is part of the first unit 40, is disposed within the main body portion 51 of the second unit 50.

[0031] The connection structure between the second unit 50 and the first unit 40 will be described with reference to FIG. 2 . At least one through-hole 56 is provided in the bottom plate 54 of the main body 51. The through-hole 56 penetrates the bottom plate 54 in the Z direction, which is the plate thickness direction. As shown in FIG. 3( b), the bottom plate 54 is provided with three through-holes 56 arranged at the vertices of a triangle. Each through-hole 56 includes an upper opening 56a formed in the upper surface 54a, a lower opening 56b formed in the lower surface 54b, and a tapered portion 56c connecting the upper opening 56a and the lower opening 56b. The inner diameter D2 of the lower opening 56b is smaller than the inner diameter D1 of the upper opening 56a. The tapered portion 56c is provided so that the inner diameter of the through-hole 56 decreases as it approaches the bottom of the bottom plate 54. The tapered portion 56c has a truncated cone shape that widens toward the top of the bottom plate 54.

[0032] At least one connecting portion 43 is inserted into a through-hole 56 in the bottom plate portion 54 of the main body portion 51 of the second unit 50, and connects the upper plate portion 41 and the contact plate portion 42. The at least one connecting portion 43 has three connecting portions 43 arranged at the vertices of a triangle in a plan view.

[0033] The connecting portion 43 has a supported portion 43a and a columnar portion 43b. The supported portion 43a is supported by the bottom plate portion 54 at or near the through hole 56. In this embodiment, the multiple supported portions 43a are provided on the lower surface 41a of the upper plate portion 41. The multiple supported portions 43a are each supported at a predetermined position in the horizontal direction by the bottom plate portion 54. For example, the multiple supported portions 43a are supported by tapered portions 56c in each of the multiple through holes 56. The supported portion 43a is provided so that its outer diameter decreases as it approaches the bottom of the supported portion 43a. The supported portion 43a has a truncated cone shape that widens toward the top of the supported portion 43a.

[0034] The columnar portion 43b connects the supported portion 43a and the contact plate portion 42. The columnar portion 43b is disposed below the supported portion 43a. When the second unit 50 separates from the first unit 40 and the second unit 50 descends relative to the first unit 40, the supported portion 43a moves relatively above the bottom plate portion 54. At this time, the columnar portion 43b is inserted into the through hole 56. When the columnar portion 43b is inserted into the through hole 36, a gap exists between the columnar portion 43b and the through hole 36 (around the columnar portion 43b) in all horizontal directions. For example, the inner diameter of the through hole 36 is larger than the outer diameter of the columnar portion 43b by a predetermined amount of misalignment. This allows the columnar portion 43b to be displaced to some extent relative to the lower opening 36b of the through hole 36 in the horizontal direction. In this manner, the columnar portion 43b is disposed within the through hole 56 so as to be movable up and down. The plurality of columnar portions 43b are arranged in the plurality of through holes 56 so as to be able to move up and down.

[0035] Next, a description will be given of the configuration related to the transfer and positioning of the first unit 40 during teaching, and the configuration related to position measurement (position detection). The contact plate portion 42 of the first unit 40 includes an upper surface 42a and a plurality of (e.g., three) recesses 42c formed on a lower surface 42b (contact surface). The plurality of recesses 42c are provided to correspond to the positioning pins 301 of the load port 300. Each recess 42c is formed, for example, by two inclined surfaces and has a V-shaped cross section. When the first unit 40 is transferred to the load port 300, the three positioning pins 301 enter the three recesses 42c, thereby positioning the first unit 40 relative to the load port 300.

[0036] 2 and 3A, the first unit 40 includes a detection plate 32 provided on the upper surface 41b of the upper plate portion 41, and a marker 46 provided on the detection plate 32. The marker 46 is a detection portion and is disposed at the center of the detection plate 32. When the first unit 40 is positioned relative to the load port 300, the marker 46 is located at a reference position in the center of the three positioning pins 301 in a plan view. The detection plate 32 and the marker 46 are detected by a measurement unit of the second unit 50.

[0037] As shown in FIGS. 2 and 4 , the main body 51 of the second unit 50 is provided with a measurement unit including a camera unit 57 and three distance sensors 58. The second unit 50 has these measurement units and a teaching control unit 60. The camera unit 57 captures an image of the detection target plate 32. The camera unit 57 detects the markers 46 on the detection target plate 32. The camera unit 57 outputs the captured image to the teaching control unit 60. The three distance sensors 58 are fixed to either the pair of side wall units 55 or the top plate unit 53. Each distance sensor 58 detects the distance to the detection target plate 32 on the top plate unit 41. The optical axis of each distance sensor 58 is arranged to intersect with the top plate unit 41. The three distance sensors 58 output the distance between each distance sensor 58 and the detection target plate 32 on the top plate unit 41 in the Z direction to the teaching control unit 60. The camera unit 57 and the distance measurement sensor 58 measure the position of the first unit 40 .

[0038] The second unit 50 has a deceleration sensor 59 and a communication unit 28. The deceleration sensor 59 is provided, for example, on one of the side wall portions 55, with its optical axis facing downward. The deceleration sensor 59 measures the distance to an object present below the teaching unit 20. For example, the deceleration sensor 59 measures the distance to the load port 300. The deceleration sensor 59 outputs the measured distance to the teaching control unit 60. The communication unit 28 is configured to be able to communicate with the communication unit 18 provided in the holding unit 7 of the ceiling transport vehicle 1. For example, the communication unit 28 can optically communicate with the communication unit 18. This eliminates the need for an electrical connection between the teaching unit 20 and the ceiling transport vehicle 1, allowing teaching using the teaching unit 20 to be performed automatically without human intervention.

[0039] The teaching control unit 60 is a control unit that controls various functions of the teaching unit 20. The teaching control unit 60 outputs information related to teaching to the transport vehicle controller 8 via the communication units 28 and 18.

[0040] Next, a configuration for checking the installation status of the first unit 40 will be described with reference to FIGS. 2 and 4 . As shown in FIGS. 2 and 4 , in the teaching unit 20 of this embodiment, the first unit 40 has a display device 44 that outputs information indicating the installation status of the first unit 40 relative to the load port 300. The display device 44 includes a lighting unit 49 (or a light-emitting unit; see also FIG. 3A ) installed on the upper surface 41 b of the upper plate 41. The display device 44 includes, for example, a plurality of switch units 48 installed on the upper surface 42 a of the contact plate 42, and a plurality of wirings 45 connecting the plurality of switch units 48 and the lighting unit 49. A battery 47 is provided at one location on the wirings 45, and serves as a power source for supplying power to the lighting unit 49 and outputting signals from the switch units 48 to the lighting unit 49. The battery 47 is installed, for example, at a position on the upper surface 42 a of the contact plate 42 so as not to interfere with the connecting unit 43. The wiring 45 passes through an appropriate through-hole or outside the bottom plate portion 54 so as not to interfere with position measurement and the relative movement of the second unit 50 (separation from the first unit 40).

[0041] The lighting unit 49 is, for example, an LED. The switch unit 48 includes a switch body 48a fixed to the upper surface 42a of the contact plate 42 at the position of the through-hole 56, and a terminal 48b protruding downward from the switch body 48a and exposed at the upper end of the V-shaped groove of the recess 42c. When the three positioning pins 301 fit into the three recesses 42c and the first unit 40 is positioned relative to the load port 300, the positioning pins 301 abut against the terminal 48b. This causes the lighting unit 49 to light up. The display device 44 lights up the lighting unit 49 when the first unit 40 is installed in a position (predetermined state) on the load port 300. Note that a light source (or an emitting element when energized) other than an LED may be used as the lighting unit 49.

[0042] The teaching control unit 60 of the second unit 50 detects that the lighting unit 49 has been lit by capturing or observing the upper surface 41b with the camera unit 57. That is, the camera unit 57 is a device (measurement unit) that measures the position of the first unit 40 during teaching, and at the same time, it is a device (acquisition device) that detects that the lighting unit 49 of the display device 44 has been lit. If the teaching control unit 60 can confirm that the lighting unit 49 is lit with the camera unit 57, it determines that the first unit 40 has been positioned (i.e., correctly set). If the teaching control unit 60 cannot confirm that the lighting unit 49 is lit even after the first unit 40 has been transferred, it determines that the first unit 40 has not been positioned (i.e., it has been placed in a position other than the correct position and has not been set correctly). The above-mentioned "vi) Indication of success or failure of installation of the first unit 40" refers to whether the lighting unit 49 is lit. In addition, for example, the first unit 40 (or the second unit 50) may be provided with a display unit that indicates whether the installation of the first unit 40 was successful.

[0043] 2, 4, and 5, teaching using the teaching unit 20 will be described in detail. First, the teaching control unit 60 stops the traveling unit 3 at a predetermined position on the track R and lowers the holding unit 7 a predetermined distance based on the transfer conditions stored as initial settings. At this time, the deceleration sensor 59 detects that the holding unit 7 has lowered the predetermined distance.

[0044] Next, as shown in FIG. 5 , the teaching control unit 60 lowers the holding unit 7 to transfer the first unit 40 to the load port 300. The second unit 50 and the first unit 40 are positioned relative to the load port 300. The teaching control unit 60 detects the illumination of the lighting unit 49 via the camera unit 57 (see FIG. 5 ). The teaching control unit 60 then further lowers the holding unit 7. As a result, the second unit 50 separates from the first unit 40 and swings with a predetermined amplitude in the Y direction. That is, when the contact plate unit 42 is supported by the load port 300, the second unit 50 separates from the first unit 40. The teaching control unit 60 calculates the average value of the information measured by the measurement unit, thereby calculating the center position of the amplitude of the swing of the second unit 50 as the position of the second unit 50.

[0045] Thereafter, the teaching control unit 60 raises the holding unit 7 and causes the second unit 50 to support the first unit 40, thereby retrieving the first unit 40 from the load port 300. When the second unit 50 supports the first unit 40, the supported portions 43 a are supported by the bottom plate portion 54 at or near the through holes 56. This guides the first unit 40 to a reference position relative to the second unit 50 in the rotation direction about the Z direction as the central axis (i.e., the rotation direction about the vertical axis) and in the horizontal direction. The multiple supported portions 43 a are supported at predetermined positions by the tapered portions 56 c in each of the multiple through holes 56. Note that the "rotation direction about the Z direction as the central axis" is the same as the "rotation direction in a horizontal plane" described above.

[0046] In this way, the teaching control unit 60 calculates how much the position of the second unit 50 has deviated from the position of the first unit 40 (the amount of correction for the transfer conditions) from the information detected by the camera unit 57 and the three distance measuring sensors 58 when the first unit 40 has been transferred to the load port 300. Then, the teaching control unit 60 outputs the amount of correction for the transfer conditions as information related to teaching to the transport vehicle controller 8 via the communication units 28 and 18.

[0047] More specifically, an image of the marker 46 is captured by the camera unit 57. Based on the captured image, the teaching control unit 60 calculates the amount of misalignment of the second unit 50 relative to the first unit 40 in the rotational direction about the Z direction as the central axis and in the horizontal direction using a known method. The three distance measurement sensors 58 also acquire the distances between the three distance measurement sensors 58 and the upper surface 41b of the upper plate portion 41. Based on the acquired three distances, the teaching control unit 60 calculates the relative tilt angle of the second unit 50 relative to the first unit 40 (tilt about the X-axis or Y-axis in the horizontal plane) using a known method, and can calculate a correction amount for the transfer conditions. As a result, the teaching control unit 60 detects the amount of misalignment of the second unit 50 relative to the first unit 40 in the rotational direction about the X-axis, Y-axis, and Z-axis as the central axes and in the horizontal direction. When capturing an image using the camera unit 57, control may be performed to turn off the lighting unit 49 (for example, by cutting off the circuit using the wiring 45), or the image may be captured using the camera unit 57 while the lighting unit 49 remains lit.

[0048] The area controller 110 controls the ceiling transport vehicle 1 to have the holding unit 7 hold the teaching unit 20, and executes teaching of the transfer operation using the teaching unit 20. More specifically, the area controller 110 executes holding control to make the ceiling transport vehicle 1 travel toward a storage location such as a buffer where the teaching unit 20 is stored, stop at the storage location, lower the holding unit 7, and have the holding unit 7 hold the teaching unit 20. The area controller 110 executes teaching control to make the ceiling transport vehicle 1 holding the teaching unit 20 travel toward a transfer position relative to the load port 300, stop at the transfer position, and executes teaching control to acquire teaching data by having the ceiling transport vehicle 1 perform a transfer operation relative to the load port 300.

[0049] Furthermore, after the above-mentioned holding control, the area controller 110 executes teaching control for a plurality of load ports 300 and buffers (storage shelves), etc. The area controller 110, for example, causes the ceiling transport vehicle 1 holding the teaching unit 20 to travel toward a transfer position for a predetermined load port 300 (or buffer, etc.). The area controller 110 stops the ceiling transport vehicle 1 at the transfer position for the predetermined load port 300 and executes teaching for the predetermined load port 300. When teaching for the predetermined load port 300 is completed, the area controller 110 causes it to travel toward a transfer position for another load port 300.

[0050] Such a series of teaching may be configured to be automatically performed by the area controller 110 based on some kind of trigger. Examples of triggers include when a scheduled execution date arrives, when the vibration value generated when the container 200 is transferred to the load port 300 exceeds a threshold, when a transfer abnormality or an event that is a symptom of such an abnormality occurs, etc.

[0051] The area controller 110 stores the information relating to the teaching of each load port 300 acquired in this manner and transmits it to each ceiling transport vehicle 1. Each ceiling transport vehicle 1 transfers the container 200 to each load port 300 based on the transfer conditions stored in the transport vehicle controller 8 and the information relating to the teaching transmitted from the area controller 110.

[0052] If the first unit 40 is not installed correctly, the lighting unit 49 will not light up. In this case, the camera unit 57 detects this and reports information that "first unit installation failed" to the transport vehicle controller 8. The transport vehicle controller 8 receives the information about the installation failure and performs the installation operation again (raising and lowering the teaching unit 20) an arbitrary number of times. If the installation of the first unit 40 is not successful even after repeating this operation (retrying) an arbitrary number of times, the transport vehicle controller 8 considers the teaching to have failed and ends the teaching operation.

[0053] According to the teaching unit 20 of this embodiment, the acquisition device of the second unit 50 acquires information indicating the installation status of the first unit 40 relative to the load port 300. This allows the second unit 50 to recognize that the first unit 40 is correctly set on the load port 300. Therefore, whether the first unit 40 is correctly set on the load port 300 can be recognized within the teaching unit 20 without using the ceiling transport vehicle 1. When the first unit 40 is correctly set on the load port 300, the amount of positional deviation can be detected based on the relative positional relationship of the second unit 50 with respect to the first unit 40, allowing for optimal teaching. The conventional teaching unit described in Patent Document 1 requires a wireless device to be installed. A receiver is also required on the ceiling transport vehicle. Wireless communication is prone to communication interruptions and interference. This embodiment uses a simpler method, and the camera unit 57 not only measures the position but also determines whether the installation of the first unit 40 is normal or abnormal. Furthermore, measurements and judgments related to teaching are performed within the teaching unit 20, and only the results are passed to the ceiling transport vehicle 1.

[0054] The display device 44 equipped with the lighting unit 49 and the camera unit 57 (acquisition device) make it possible to easily determine with a simple configuration whether the first unit 40 has been correctly set on the load port 300.

[0055] Furthermore, when the second unit 50 descends and the first unit 40 is separated from the second unit 50, the support of the supported portion 43 a by the bottom plate portion 54 is released, the columnar portion 43 b is inserted into the through-hole 56, and a certain degree of movement of the columnar portion 43 b in the horizontal direction relative to the through-hole 56 is permitted. This allows the second unit 50 to move relative to the first unit 40 in the rotational direction about the vertical axis and in the horizontal direction in the teaching unit 20. As a result, the amount of positional deviation of the second unit 50 relative to the first unit 40 in the rotational direction about the vertical axis and in the horizontal direction can be detected with high accuracy.

[0056] Next, a teaching unit 20A according to a second embodiment will be described with reference to FIGS. 6 to 8. The teaching unit 20A shown in FIG. 6 differs from the teaching unit 20 according to the previous embodiment in that, instead of the first unit 40 having the contact plate 42 that fits over the positioning pins 301, a first unit 40A having a touch panel-type position detection device 70 that contacts the positioning pins 301 is used. As shown in FIGS. 6 and 7, the position detection device 70 includes a touch panel 71 and an output unit 75. The touch panel 71 includes a main body plate (contact plate) 72 that is disposed in a position similar to the contact plate 42 (see FIG. 2) of the previous embodiment and extends parallel to the upper plate 41 (extending along the XY plane), and multiple (e.g., three) contact surface portions (contact surfaces) 73 that are disposed on the underside of the main body plate 72 at positions corresponding to the positioning pins 301.

[0057] A substrate 61 is attached within the main body 51 of the second unit 50A. The position detection device 70 includes a plurality of wirings 65 connecting each contact surface 73 to the substrate 61. The wirings 65 are provided across the first unit 40A and the second unit 50A, but are structured so as not to interfere with the various usage modes described above. That is, the wirings 65 pass through appropriate through-holes or outside the bottom plate 54 so as not to interfere with position measurement and the relative movement of the second unit 50A (separation from the first unit 40A). More specifically, the wirings 65 are made of an appropriate wiring material that is sufficiently soft so as not to impede the swinging of the second unit 50A.

[0058] The contact surface 73 has a predetermined area corresponding to the predetermined deviation tolerance described above, for example. The contact surface 73 detects the contact points of the positioning pins 301 in the X and Y directions using a known detection mechanism, such as a capacitance or infrared detection mechanism. The touch panel 71 detects the installation position of the first unit 40A relative to the load port 300. The position detection device 70 transmits a position detection signal to the substrate 61 via the output unit 75. The substrate 61 reads the detection results from the touch panel 71. The detection results from the touch panel 71 include, for example, positional deviation information of the first unit 40A in the X and Y directions. As shown in FIG. 8 , the positional deviation information includes, for example, the positional deviation amount (distance and direction) of a center line L1 of the touch panel 71 relative to a reference position (center line C) at the center of the three positioning pins 301.

[0059] The camera unit 57 of the second unit 50 measures the position of the first unit 40A by capturing an image of the detection plate 32 (marker 46). At this time, the amount of positional deviation of the center line L2 of the second unit 50A from the center line L1 is obtained. The teaching control unit 60 of the second unit 50A corrects the detection result by the touch panel unit 71 using the measurement result by the camera unit 57. For example, the amount of positional deviation of the center line L2 of the second unit 50A from the center line L1 is added to the amount of positional deviation of the center line L1 of the touch panel unit 71 from the center line C. This determines the total (aggregated) positional deviation amount D.

[0060] The teaching unit 20A according to the second embodiment also makes it possible to determine within the teaching unit 20A whether the first unit 40A has been correctly set on the load port 300, without using the ceiling transport vehicle 1. When the first unit 40A has been correctly set on the load port 300, the amount of positional deviation can be detected based on the relative positional relationship of the second unit 50A with respect to the first unit 40A, allowing teaching to be carried out appropriately. This makes it possible to detect the amount of positional deviation of the second unit 50A with respect to the load port 300, allowing teaching to be carried out appropriately.

[0061] Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. For example, in each of the above embodiments, an example has been described in which the second unit 50 has a measuring unit (camera unit 57, distance measurement sensor 58, etc.) and the first unit 40 has a measured unit. Conversely, the first unit 40 may have a measuring unit such as the camera unit 57, and the second unit 50 may have a measured unit. Furthermore, in the first embodiment, the camera unit 57 serves as both the measuring unit and the acquisition device, but the measuring unit and the acquisition device may be provided separately.

[0062] In the above embodiment, the bottom plate portion 54 of the second unit 50 has a plurality of through holes 56, but this is not limited thereto. For example, the bottom plate portion 54 may have one or more through holes 56. The number of through holes 56 in the second unit 50 is equal to the number of columnar portions 43b (connecting portions 43) in the first unit 40. The inner surface of one or more through holes 56 may have a truncated pyramidal shape that widens toward the top of the bottom plate portion 54. In the above embodiment, each of the plurality of through holes 56 is provided with a tapered portion 56c such that the inner diameter of the through hole 56 decreases as it approaches the bottom of the bottom plate portion 54. However, this is not limited thereto. It is sufficient that the supported portion 43a is supported at a predetermined position by the bottom plate portion 54 at or near the through hole 56.

[0063] In each of the above embodiments, the first unit 40 is connected to the second unit 50 in a loosely fitted state. However, the second unit 50 and the first unit 40 may be integrated. Alternatively, the first unit 40 may not be connected to the second unit 50, and the first unit 40 may be placed on the measurement target by someone other than the ceiling transport vehicle 1 (for example, an operator).

[0064] The output device may be an output device other than the lamp-type display device 44 or the touch panel-type position detection device 70. For example, the first unit may be provided with a transmission sensor, a contact sensor, an acoustic device, or the like as the output device.

[0065] The teaching unit of the present disclosure may not only control the transfer operation, but may also teach operating positions for operations other than transfer. The measurement target portion is not limited to the load port 300. The teaching unit of the present disclosure can be applied to any predetermined position (measurement target portion) to which a transported object can be transferred by the ceiling transport vehicle 1.

[0066] 1...ceiling transport vehicle, 20, 20A...teaching unit, 40, 40A...first unit, 42...contact plate portion, 42b...underside, 43a...supported portion, 43b...columnar portion, 44...display device (output device), 47...battery, 49...lighting portion (output device), 50, 50A...second unit, 51...main body portion, 54...bottom plate portion, 56...through hole, 57...camera portion (measurement portion, acquisition device), 58...distance measuring sensor (measurement portion), 60...teaching control portion, 61...substrate portion (acquisition device), 70...position detection device (output device, measurement portion), 71...touch panel portion (output device, measurement portion), 72...main body plate (contact plate portion), 73...contact surface portion (contact surface), 75...output portion, 200...container (transported object), 300...load port (measurement target portion).

Claims

1. A teaching unit for teaching an operating position relative to a part to be measured in an overhead transport vehicle, comprising: a first unit that is installed in a predetermined state on the part to be measured; and a second unit that is detachably connected to the first unit, has a measuring unit that measures the position of the first unit, and is held so that it can be raised and lowered by the overhead transport vehicle, wherein the first unit has an output device that outputs information indicating the installation state of the first unit relative to the part to be measured, and the second unit has an acquisition device that acquires the information output from the output device.

2. The teaching unit of claim 1, wherein the output device is a display device that lights up a lighting section when the first unit is installed in a predetermined state on the measurement target section, and the acquisition device detects that the lighting section has been turned on.

3. A teaching unit as described in claim 1, wherein the output device is a position detection device including a touch panel unit that detects the installation position of the first unit relative to the measurement target unit, and the acquisition device acquires the detection results from the position detection device and corrects the detection results using the measurement results from the measurement unit.

4. A teaching unit as described in any one of claims 1 to 3, wherein the second unit includes a bottom plate portion having at least one through hole, the first unit includes at least one supported portion supported by the bottom plate portion at or near the through hole, a contact plate portion located below the bottom plate portion and including a contact surface that comes into contact with the portion to be measured, and at least one columnar portion that connects the supported portion and the contact plate portion and is movable up and down within the through hole, and when the second unit is lowered and the contact plate portion of the first unit is supported by the portion to be measured, the first unit is separated from the second unit.

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