Teaching unit and overhead transport system

Abstract

This teaching unit comprises a first unit and a second unit that is supported by the first unit in a separable manner. The first unit includes a body section and one of a part to be detected and a detection part attached to the body section. The second unit includes the other of the part to be detected and the detection part. When the second unit is placed on a transfer part, the second unit is positioned with respect to the transfer part and separated from the first unit. By detecting the part to be detected, the detection part detects the positional offset of the second unit with respect to the first unit in the horizontal direction and a rotation direction centered on a vertical axis.

Description

Teaching unit and ceiling transport vehicle system

[0001] The present disclosure relates to a teaching unit and an overhead transport vehicle system.

[0002] A conventional overhead guided vehicle system includes an overhead guided vehicle that transports an object and a teaching unit used for teaching when the overhead guided vehicle transfers the object to a transfer section where the object is placed. The teaching unit described in Patent Document 1 includes a unit body and a teaching plate. When the teaching plate is supported by the unit body, it is positioned in the front-rear and left-right directions relative to the unit body.

[0003] Japanese Patent Application Laid-Open No. 2021-187563

[0004] In the teaching unit of Patent Document 1, when the teaching plate is separated from the unit body, the unit body is allowed to shift in position relative to the teaching plate in a certain direction. However, if the unit body shifts in position relative to the teaching plate in another direction, the position of the unit body may be restricted by the teaching plate. Therefore, it may be impossible to accurately and automatically detect the positional shift of the teaching plate relative to the unit body in the rotational direction about the vertical axis and in the horizontal direction.

[0005] The present disclosure aims to provide a teaching unit and a ceiling transport system that can automatically and accurately detect the positional deviation of a first unit relative to a second unit in the rotational direction around a vertical axis and in the horizontal direction.

[0006] [1] A teaching unit according to one aspect of the present disclosure is a teaching unit used for teaching when transferring an object to a transfer section on which the object is placed by an overhead transport vehicle, and includes a first unit held so as to be freely raised and lowered on the overhead transport vehicle, and a second unit supported so as to be freely separable from the first unit, the first unit having a main body including a bottom plate and one of a detected part and a detecting part attached to the main body, the bottom plate having at least one through hole, and the second unit having a contact point with the bottom plate at or near the through hole. the second unit has at least one supported portion supported by the bottom plate portion, a contact plate portion located below the bottom plate portion and including a contact surface that contacts the transfer portion, 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 the other of the detected portion and the detecting portion, and when the second unit is placed on the transfer portion, the second unit is positioned relative to the transfer portion and separated from the first unit, and the detecting portion detects the detected portion to detect a positional deviation of the second unit relative to the first unit in the rotational direction about the vertical axis and in the horizontal direction.

[0007] According to the teaching unit of [1] above, when the second unit is separated from the first unit, the support of the supported portion by the bottom plate portion is released, and the columnar portion is inserted into the through-hole, allowing a certain degree of positional deviation of the supported portion relative to the through-hole in the horizontal direction. This allows the teaching unit to allow positional deviation of the first unit relative to the second unit in the rotational direction about the vertical axis and in the horizontal direction. As a result, the positional deviation of the first unit relative to the second unit in the rotational direction about the vertical axis and in the horizontal direction can be detected with high accuracy. As a result, the positional deviation of the first unit relative to the second unit in the rotational direction and the horizontal direction can be detected with high accuracy automatically.

[0008] [2] In the teaching unit of [1] above, when the first unit supports the second unit, the supported portion may be supported by the bottom plate portion at or near the through hole, thereby guiding the second unit to a reference position relative to the first unit in the rotational direction about the vertical axis and the horizontal direction. In this case, when the first unit supports the second unit, the second unit is guided to a reference position relative to the first unit in the rotational direction about the vertical axis and the horizontal direction. This allows the ceiling transport vehicle to automatically retrieve the teaching unit. As a result, the ceiling transport vehicle can automatically perform teaching repeatedly.

[0009] [3] In the teaching unit of [2] above, the bottom plate may be provided with a plurality of through holes, and the second unit may have a plurality of supported parts that are each supported at a predetermined position in the horizontal direction by the bottom plate, and a plurality of columnar parts that are movable up and down in each of the plurality of through holes. In this case, when the first unit supports the second unit, the plurality of supported parts of the second unit are automatically guided to predetermined positions in the horizontal direction on the bottom plate of the main body of the first unit. This makes it possible to automatically guide the second unit to a reference position relative to the first unit in the horizontal direction and in the rotational direction about the vertical axis.

[0010] [4] In the teaching unit of [3] above, each of the plurality of through holes may be provided with a tapered portion such that the inner diameter of the through hole decreases as the hole approaches the bottom plate portion, and the plurality of supported portions may be supported by the tapered portion in each of the plurality of through holes. In this case, when the first unit rises and supports the second unit, the second unit can be automatically and stably guided to a reference position relative to the first unit in the horizontal direction.

[0011] [5] In the teaching unit of any one of [1] to [4] above, the inner surface of the through hole may be provided with a plurality of inclined surfaces that face in different directions and that guide the supported part to a predetermined position in the horizontal direction. In this case, when the first unit rises and supports the second unit, the bottom plate portion having one or more through holes can automatically guide the second unit to a predetermined position relative to the first unit in the rotational direction about the vertical axis and in the horizontal direction.

[0012] [6] In the teaching unit of any one of [1] to [5] above, the first unit may have a detected part, and the second unit may have a detecting part. In this case, the weight of the second unit increases. As a result, when the first unit rises and supports the second unit, the second unit can be automatically and stably guided to a predetermined position relative to the first unit in the rotational direction about the vertical axis and in the horizontal direction.

[0013] [7] In the teaching unit of [6] above, the second unit may further include a battery that supplies power to the detection unit. In this case, the weight of the second unit is further increased. This makes it easier to automatically guide the second unit to a predetermined position relative to the first unit in the rotational direction about the vertical axis and in the horizontal direction when the first unit rises and supports the second unit. Furthermore, compared to when the second unit does not include a battery, there is no need to electrically connect the second unit to components other than the second unit to supply power to the detection unit of the second unit. As a result, the teaching unit can be realized with a simpler configuration.

[0014] [8] An overhead transport vehicle system according to an aspect of the present disclosure may include an overhead transport vehicle that transports an object to be transported, and any one of the teaching units described above in [1] to [7]. In this case, positional deviations in each direction during the transfer operation of the overhead transport vehicle can be detected automatically with high accuracy.

[0015] [9] An overhead transport vehicle system according to one aspect of the present disclosure may include an overhead transport vehicle for transporting an object, the teaching unit described in [7] above, and a storage shelf for storing the teaching unit. The storage shelf may have a battery charging mechanism. In this case, the battery can be charged when the teaching unit is stored. As a result, teaching using the overhead transport vehicle can be performed more efficiently.

[0016] According to the present disclosure, it is possible to easily and automatically detect the positional deviation of the second unit relative to the first unit in the rotational direction about the vertical axis and in the horizontal direction.

[0017] FIG. 1 is a side view showing an overhead transport vehicle, a transfer unit, and a teaching unit according to one embodiment. FIG. 2 is a block diagram showing the functional configuration of an overhead transport vehicle system. FIG. 3 is a cross-sectional view showing a teaching unit according to one embodiment. FIG. 4(a) is a view showing the underside of the top plate of the first unit in FIG. 3, and FIG. 4(b) is a view showing the upper surface of the bottom plate of the first unit in FIG. 3. FIG. 5(a) is a view showing the underside of the contact plate of the second unit in FIG. 3, FIG. 5(b) is a cross-sectional view showing the contact plate and multiple connecting portions of the second unit along line V-V in FIG. 3, and FIG. 5(c) is a view showing the upper plate and detection unit of the second unit in FIG. 3. FIGS. 6(a) to 6(c) are diagrams for explaining teaching using the teaching unit. FIG. 7 is a side view showing a storage shelf for the teaching unit in FIG. 1. FIG. 8 is a cross-sectional view showing a teaching unit according to a first modified example. FIG. 9 is a cross-sectional view showing a teaching unit according to a second modified example. Fig. 10 is a diagram showing the upper plate portion, detected portion, and detecting portion of the second unit of the teaching unit shown in Fig. 9. Fig. 11 is a cross-sectional view showing a calibration table used for calibrating the detecting portion.

[0018] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the description of the drawings, the same elements are designated by the same reference numerals, and duplicated description will be omitted.

[0019] 1 and 2, the ceiling transport vehicle system 100 will be described. The ceiling transport vehicle system 100 includes a plurality of ceiling transport vehicles 1, a teaching unit 20, and an area controller 110 (see FIG. 2).

[0020] As shown in Figure 1, an overhead transport vehicle 1 in one embodiment 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 300 (transfer unit) or the like provided in a processing device that performs various processes on the semiconductor wafers. The container 200 has a flange 223 formed thereon that is held by a pair of grippers 12, 12 of the overhead transport vehicle 1.

[0021] 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).

[0022] 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 in a lateral direction (Y direction) 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.

[0023] 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 X direction. The pair of grippers 12 are opened and closed by a drive motor (not shown) and a link mechanism (not shown). In this embodiment, the height position of the holding unit 7 is adjusted so that, when the pair of grippers 12 are in an open state, 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.

[0024] 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.

[0025] The transport vehicle controller 8 of this embodiment 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.

[0026] 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 the teaching unit 20, which will be described in detail later, is attached.

[0027] 2 is an electronic control unit including a processor such as a CPU, a ROM, a RAM, etc. 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.

[0028] The area controller 110 communicates with the 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.

[0029] In the ceiling transport vehicle system 100 as described above, teaching is performed when the ceiling transport vehicle 1 starts transporting the container 200 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 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.

[0030] FIG. 3 is a cross-sectional view showing the teaching unit 20 according to this embodiment. The teaching unit 20 is used for teaching when the overhead transport vehicle 1 transfers the container 200 to the load port 300 on which the container 200 is placed. As shown in FIG. 3 , the teaching unit 20 includes a first unit 30 and a second unit 40. 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 a lateral direction perpendicular to the traveling direction. The following description is based on the use state of the teaching unit 20 when the load port 300 (transfer unit) is arranged along the X direction (see FIG. 1 ). However, depending on the orientation of the load port 300, the teaching unit 20 may be rotated horizontally. Therefore, the X direction can also be interpreted as "a certain direction in the horizontal direction" and the Y direction can also be interpreted as "another direction perpendicular to a certain direction in the horizontal direction." In other words, the Y direction can also be interpreted as "a direction perpendicular to the X direction and the Z direction (vertical direction)."

[0031] The first unit 30 is held by the holding unit 7 of the ceiling transport vehicle 1 so as to be able to move up and down freely. The first unit 30 has a main body 31 and a detected part 32. The main body 31 includes a flange 23. The flange 23 is held by grippers 12, 12 (see FIGS. 1 and 2 ) that are mounted on the holding unit 7 of the ceiling transport vehicle 1 and are raised and lowered. The flange 23 is located in the center of the upper part of the main body 31.

[0032] The main body 31 further includes a top plate 33, a bottom plate 34, and two side wall portions 35. The top plate 33 and the bottom plate 34 are spaced apart in the Z direction and face each other. The top plate 33 extends in the X direction and Y direction below the flange 23. The bottom plate 34 extends in the X direction and Y direction below the top plate 33. The two side wall portions 35 are spaced apart in the X direction and face each other. One side wall portion 35 extends in the Z direction from one end of the top plate 33 in the X direction to the bottom plate 34. The other side wall portion 35 extends in the Z direction from the other end of the top plate 33 in the X direction to the bottom plate 34. The main body 31 may further include two side wall portions spaced apart in the Y direction and facing each other.

[0033] The detected portion 32 is attached to the main body portion 31. The detected portion 32 is detected by a detection portion 44 (described later) of the second unit 40. FIG. 4A is a diagram showing the lower surface 33a of the top plate portion 33. The detected portion 32 includes a detected plate 32a provided on the lower surface 33a and a marker 32b provided on the detected plate 32a. The marker 32b is disposed at the center of the detected plate 32a. The detected plate 32a functions as a detected surface of the detected portion 32 (details will be described later).

[0034] At least one through hole 36 is provided in the bottom plate portion 34. The through hole 36 penetrates the bottom plate portion 34 in the Z direction, which is the plate thickness direction. FIG. 4B is a diagram showing the upper surface 34a of the bottom plate portion 34. In this embodiment, the bottom plate portion 34 is provided with a plurality of through holes 36. For example, the plurality of through holes 36 includes three through holes 36 arranged at the vertices of a triangle in a plan view. The through hole 36 has an upper opening 36a and a lower opening 36b. The upper opening 36a includes the lower opening 36b inside in a plan view. The inner diameter D2 of the lower opening 36b is larger than the outer diameter of the columnar portion 43b (described below) and is larger than the outer diameter of the columnar portion 43b by at least a predetermined misalignment tolerance. The inner diameter D2 of the lower opening 36b is larger than the outer diameter of the columnar portion 43b (described below) by at least the width W of the recess (described below). The inner diameter D1 of the upper opening 36a and the inner diameter D2 of the lower opening 36b are set according to the allowable amount of misalignment.

[0035] Each of the plurality of through holes 36 has a tapered portion 36c. The tapered portion 36c is provided so that the inner diameter of the through hole 36 decreases as it approaches the bottom of the bottom plate portion 34. For example, the tapered portion 36c connects the upper opening 36a and the lower opening 36b. The tapered portion 36c has a truncated cone shape that widens toward the top of the bottom plate portion 34.

[0036] As shown in Fig. 3, the second unit 40 is supported by the first unit 30 so as to be freely separable. The second unit 40 has an upper plate portion 41, a contact plate portion 42, at least one connecting portion 43, and a detection portion 44. 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 the upper surface 34a of the bottom plate portion 34. The contact plate portion 42 is located below the bottom plate portion 34.

[0037] The contact plate 42 includes an upper surface 42a and a lower surface 42b (contact surfaces). FIG. 5A is a diagram showing the lower surface 42b of the contact plate 42 of the second unit 40 of the teaching unit 20. As shown in FIG. 5A, the lower surface 42b is provided with recesses 42c corresponding to the positioning pins 301 of the load port 300. The recesses 42c are formed, for example, by two inclined surfaces and have a V-shaped cross section. The width W of the recesses 42c is, for example, 60 mm. The surfaces of the two inclined surfaces are made of a material with good sliding properties. For example, three recesses 42c are provided on the lower surface 42b. When the second unit 40 is transferred (placed) on the load port 300, the three positioning pins 301 are accommodated in the three recesses 42c, thereby positioning the second unit 40 relative to the load port 300.

[0038] At least one connecting portion 43 is inserted into the through-hole 36 in the bottom plate portion 34 of the main body portion 31 in the first unit 30, and connects the upper plate portion 41 and the contact plate portion 42. Fig. 5(b) is a cross-sectional view showing the contact plate portion 42 and the multiple connecting portions 43 taken along line V-V in Fig. 3. As shown in Fig. 5(b), the at least one connecting portion 43 has three connecting portions 43 arranged at the vertices of a triangle in a plan view.

[0039] 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 34 at or near the through hole 36. 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 34. Specifically, the multiple supported portions 43a are supported by the tapered portion 36c in each of the multiple through holes 36. For example, the supported portions 43a are configured so that their outer diameters decrease as they approach the bottom of the supported portion 43a. As one example, the supported portion 43a has a truncated cone shape that widens toward the top of the supported portion 43a. As another example, the supported portion 43a may have a hemispherical shape that widens toward the top of the supported portion 43a.

[0040] 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. The outer diameter of the columnar portion 43b is, for example, 20 mm.

[0041] When the first unit 30 is separated from the second unit 40 and the first unit 30 is lowered relative to the second unit 40, the supported portion 43a is positioned above the through hole 36 or the bottom plate portion 34. The columnar portion 43b is inserted into the through hole 36. When the columnar portion 43b is inserted into the through hole 36, a gap is formed 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 tolerance. 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 way, the columnar portion 43b is arranged to be able to move up and down within the through hole 36. For example, multiple columnar portions 43b are arranged to be able to move up and down within each of the multiple through holes 36.

[0042] The detecting unit 44 detects the detected portion 32. The detecting unit 44 is provided on the upper surface 41b of the top plate 41. The detecting unit 44 has a camera sensor 44a and three distance measuring sensors 44b. The camera sensor 44a detects the marker 32b on the detected plate 32a by capturing an image of the detected plate 32a provided on the lower surface 33a of the top plate 33. The camera sensor 44a outputs the captured image to the teaching control unit 50.

[0043] The three distance measuring sensors 44b are fixed to the upper surface 41b of the upper plate portion 41 (see FIG. 5C). The optical axis of each distance measuring sensor 44b is arranged to intersect with the top plate portion 33. Each distance measuring sensor 44b detects the detection target plate 32a (i.e., the detection target surface of the detection target portion 32) located above the respective distance measuring sensor 44b, thereby detecting the distance between each distance measuring sensor 44b and the detection target surface of the detection target portion 32 in the Z direction. The three distance measuring sensors 44b each output the distance between each distance measuring sensor 44b and the upper surface 41b of the upper plate portion 41 in the Z direction to the teaching control unit 50.

[0044] Referring again to Figure 3, the second unit 40 further includes a deceleration sensor 45, a communication unit 46, and a battery 47. The deceleration sensor 45 is provided on the contact plate unit 42 of the second unit 40, and its optical axis is directed downward from the contact plate unit 42. The deceleration sensor 45 measures the distance to an object present below the teaching unit 20. For example, the deceleration sensor 45 measures the distance to the load port 300. The deceleration sensor 45 outputs the measured distance to the teaching control unit 50.

[0045] The communication unit 46 is configured to be able to communicate with another communication unit 71 provided in the holding unit 7 of the ceiling transport vehicle 1. For example, the communication unit 46 can optically communicate with the other communication unit 71. 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. The battery 47 is provided on the contact plate portion 42 of the second unit 40 and supplies power to the detection unit 44, the deceleration sensor 45, and the communication unit 46. Note that the communication method between the communication unit 46 and the other communication unit 71 is not limited to the above and may be any known communication method. Furthermore, the communication unit 46 and the battery 47 are arranged so as not to interfere with the first unit 30 separated from the second unit 40.

[0046] The teaching control unit 50 is a control unit that controls various functions of the teaching unit 20. The teaching control unit 50 outputs information related to teaching to the transport vehicle controller 8 via the communication unit 46 and another communication unit 71. Teaching using the teaching unit 20 will be described in detail with reference to Figures 6(a) to 6(c). The communication unit 46, battery 47, and another communication unit 71 are not shown in Figures 6(a) to 6(c).

[0047] 6(a), based on the transfer conditions stored as initial settings, the teaching control unit 50 stops the traveling unit 3 at a predetermined position on the track R and lowers the holding unit 7 a predetermined distance. At this time, the deceleration sensor 45 detects that the holding unit 7 has lowered the predetermined distance.

[0048] Next, as shown in FIGS. 6B and 6C , when the second unit 40 is transferred (placed) on the load port 300, the second unit 40 is positioned relative to the load port 300 and separated from the first unit 30. Specifically, as shown in FIG. 6B , the teaching control unit 50 lowers the holding unit 7 to transfer the second unit 40 to the load port 300. The first unit 30 and the second unit 40 are positioned relative to the load port 300. Thereafter, as shown in FIG. 6C , the teaching control unit 50 further lowers the holding unit 7. The first unit 30 separates from the second unit 40 and oscillates with a predetermined amplitude in at least one of the X and Y directions. The teaching control unit 50 calculates the average value of the information detected by the detection unit 44 to calculate the center position of the amplitude of the oscillation of the first unit 30 as the position of the first unit 30.

[0049] Finally, as shown in FIG. 6A , the teaching control unit 50 raises the holding unit 7 and causes the first unit 30 to support the second unit 40, thereby recovering the second unit 40 from the load port 300. When the first unit 30 supports the second unit 40, the supported portions 43 a are supported by the bottom plate portion 34 at or near the through holes 36, thereby guiding the second unit 40 to a reference position relative to the first unit 30 in the rotational direction about the Z direction (i.e., the rotational direction about the vertical axis) and the horizontal direction. In this embodiment, the multiple supported portions 43 a are each supported at a predetermined position in the horizontal direction by the bottom plate portion 34. The multiple supported portions 43 a are supported at a predetermined position by the tapered portions 36 c in each of the multiple through holes 36. Note that the "rotational direction about the Z direction" is the same as the "rotational direction in a horizontal plane" described above.

[0050] In this way, the teaching control unit 50 calculates, from the information detected by the detection unit 44, how much the position of the first unit 30 has deviated from the position of the second unit 40 (the amount of correction for the transfer conditions) when the second unit 40 has been transferred to the load port 300. Then, the teaching control unit 50 outputs the amount of correction for the transfer conditions as information related to teaching to the transport vehicle controller 8 via the communication units 46 and 71.

[0051] In the teaching unit 20 of this embodiment, an image of the marker 32b is acquired by the camera sensor 44a. Based on the captured image, the teaching control unit 50 calculates the positional deviation of the first unit 30 relative to the second unit 40 in the rotational direction about the Z direction as the central axis and in the horizontal direction using a known method.

[0052] In the teaching unit 20 of this embodiment, the three distance measurement sensors 44b each acquire the distance between the detected plate 32a on the underside 33a of the first unit 30 and each of the three distance measurement sensors 44b. Based on the three acquired distances, the teaching control unit 50 calculates the relative tilt angle of the first unit 30 with respect to the second unit 40 (tilt about the X-axis or Y-axis in the horizontal plane) using a known method, and is able to calculate a correction amount for the transfer conditions.

[0053] In this way, when the detection unit 44 detects the detected part 32, the teaching control unit 50 detects the positional deviation of the first unit 30 relative to the second unit 40 in the rotational direction around the central axis of the X direction, Y direction, and Z direction, as well as in the horizontal direction.

[0054] As described above, 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, and stop at the transfer position to perform a transfer operation relative to the load port 300, thereby acquiring teaching data.

[0055] As shown in FIG. 7 , the buffer 400 (storage shelf) described above is arranged below the track R, similar to the load port 300. The buffer 400 stores the teaching unit 20. The buffer 400 has a plurality of positioning pins 401 and a charging mechanism 402 for the battery 47. When the teaching unit 20 is transferred (placed) on the buffer 400, the teaching unit 20 is positioned relative to the buffer 400 by the plurality of positioning pins 401. The buffer 400 may be arranged to the side of the track R in a plan view.

[0056] After the above-described holding control, the area controller 110 of this embodiment executes teaching control for a plurality of load ports 300. Specifically, the area controller 110 causes the ceiling transport vehicle 1 holding the teaching unit 20 to travel toward a transfer position for a predetermined load port 300. 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 the ceiling transport vehicle 1 to travel toward a transfer position for another load port 300.

[0057] When teaching for a specific load port 300 is completed, the area controller 110 may cause the teaching unit 20 to travel toward a storage location such as a buffer 400 where the teaching unit 20 is stored. The area controller 110 may stop at the storage location, lower the holding unit 7, and transfer the teaching unit 20 held by the holding unit 7 to the buffer 400.

[0058] 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.

[0059] 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.

[0060] According to the teaching unit 20 of this embodiment, when the second unit 40 is separated from the first unit 30, the support of the supported portion 43 a by the bottom plate portion 34 is released and the columnar portion 43 b is inserted into the through-hole 36, allowing a certain degree of positional deviation of the supported portion 43 a relative to the through-hole 36 in the horizontal direction. This allows positional deviation of the first unit 30 relative to the second unit 40 in the rotational direction about the Z direction as the central axis and in the horizontal direction in the teaching unit 20. As a result, positional deviation of the first unit 30 relative to the second unit 40 in the rotational direction about the Z direction as the central axis and in the horizontal direction can be detected with high accuracy. From the above, positional deviation of the first unit 30 relative to the second unit 40 in the rotational direction about the Z direction as the central axis and in the horizontal direction can be detected with high accuracy automatically.

[0061] When the second unit 40 is separated from the first unit 30, the first unit 30 does not come into contact with the load port 300. In this case, the position of the first unit 30 can be detected taking into account the swinging of the first unit 30. This makes it possible to automatically detect the positional deviation of the first unit 30 relative to the second unit 40 in the horizontal direction with greater accuracy.

[0062] When the first unit 30 supports the second unit 40, the supported portion 43a is supported by the bottom plate portion 34 at or near the through hole 36, thereby guiding the second unit 40 to a reference position relative to the first unit 30 in the rotational direction and horizontal direction. In this case, when the first unit 30 supports the second unit 40, the second unit 40 is guided to a reference position relative to the first unit 30 in the rotational direction around the Z direction as the central axis and in the horizontal direction. This allows the ceiling transport vehicle 1 to automatically retrieve the teaching unit 20. As a result, the ceiling transport vehicle 1 can automatically perform teaching repeatedly.

[0063] The bottom plate portion 34 is provided with a plurality of through holes 36, and the second unit 40 has a plurality of supported portions 43a that are each supported at a predetermined position in the horizontal direction by the bottom plate portion 34, and a plurality of columnar portions 43b that are movable up and down in each of the plurality of through holes 36. In this case, when the first unit 30 supports the second unit 40, the plurality of supported portions 43a of the second unit 40 are automatically guided to predetermined positions in the horizontal direction on the bottom plate portion 34 of the main body portion 31 of the first unit 30. This makes it possible to automatically guide the second unit 40 to a reference position relative to the first unit 30 in the horizontal direction and in the rotational direction about the Z direction as the central axis.

[0064] Each of the plurality of through holes 36 is provided with a tapered portion 36c such that the inner diameter of the through hole 36 decreases as it approaches the bottom of the bottom plate portion 34, and the plurality of supported portions 43a are supported by the tapered portion 36c in each of the plurality of through holes 36. In this case, after the first unit 30 descends and releases its support for the second unit 40, when the first unit 30 ascends and supports the second unit 40 again, the second unit 40 can be automatically and stably guided to the reference position relative to the first unit 30 in the horizontal direction.

[0065] The first unit 30 has a detected part 32. The second unit 40 has a detecting part 44. In this case, the weight of the second unit 40 increases. As a result, when the first unit 30 descends and releases its support for the second unit 40, and then the first unit 30 ascends and supports the second unit 40 again, the second unit 40 can be stably and automatically guided to a predetermined position relative to the first unit 30 in the rotational direction about the Z direction as the central axis and in the horizontal direction. Furthermore, because there is no need to arrange the detected part 32 on the load port 300, teaching can be performed automatically.

[0066] The detection target portion 32 has a detection target plate 32a including a marker 32b, and the detection unit 44 has a camera sensor 44a that detects the marker 32b. In this case, the detection accuracy of the camera sensor 44a can be improved.

[0067] The second unit 40 has a battery 47 that supplies power to the detection unit 44. In this case, the weight of the second unit 40 is further increased. As a result, when the first unit 30 descends and releases its support for the second unit 40, and then the first unit 30 ascends and supports the second unit 40 again, the second unit 40 can be more easily and automatically guided to a predetermined position relative to the first unit 30 in the rotational direction about the Z direction and in the horizontal direction. Furthermore, compared to when the second unit 40 does not have a battery 47, there is no need to electrically connect the second unit 40 to components other than the second unit 40 (e.g., the first unit 30) to supply power to the detection unit 44 of the second unit 40. As a result, the teaching unit 20 can be realized with a simpler configuration.

[0068] The ceiling transport vehicle system 100 of this embodiment includes a ceiling transport vehicle 1 that transports a container 200 or a teaching unit 20, and the teaching unit 20. In this case, positional deviations in each direction during the transfer operation of the ceiling transport vehicle 1 can be detected automatically with high accuracy.

[0069] The ceiling transport vehicle system 100 includes a buffer 400 for storing the teaching unit 20. The buffer 400 has a charging mechanism 402 for the battery 47. In this case, the battery 47 can be charged when the teaching unit 20 is stored. As a result, teaching using the ceiling transport vehicle 1 can be carried out more efficiently.

[0070] Although the embodiments of the present disclosure have been described above, the present invention is not limited to the above embodiments. For example, the first unit 30 may have one of the detected portion 32 and the detecting portion 44 attached to the main body 31, and the second unit 40 may have the other of the detected portion 32 and the detecting portion 44. As shown in FIG. 8 , unlike the above embodiment, in a teaching unit 120 of a first modified example, the first unit 30 may have the detecting portion 44 attached to the main body 31, and the second unit 40 may have the detected portion 32. Specifically, a camera sensor 44a of the detecting portion 44 may be provided on the lower surface 33a of the top plate 33. Three distance measuring sensors 44b of the detecting portion 44 may be supported on the inner surfaces 35a of the multiple side wall portions 35. The detected portion 32 may be provided on the upper surface 41b of the top plate 41.

[0071] In the above embodiment, the bottom plate portion 34 of the first unit 30 has multiple through holes 36, but this is not limited to this. For example, the bottom plate portion 34 may have one or more through holes 36, and the inner surface of the through hole 36 may be provided with multiple inclined surfaces facing in different directions. The multiple inclined surfaces guide the supported portion 43a to a predetermined position in the horizontal direction. As an example, the inner surface of the through hole 36 may have a truncated pyramid shape that widens toward the top of the bottom plate portion 34.

[0072] In this case, when the first unit 30 descends and releases its support for the second unit 40, and then rises and supports the second unit 40 again, the bottom plate portion 34 having one or more through holes 36 can automatically guide the second unit 40 to a predetermined position relative to the first unit 30 in the rotational direction and horizontal direction around the Z direction as the central axis.

[0073] In the above embodiment, each of the plurality of through holes 36 is provided with a tapered portion 36c such that the inner diameter of the through hole 36 decreases as it approaches the bottom of the bottom plate portion 34. However, this is not limiting. It is sufficient that the supported portion 43a is supported at a predetermined position by the bottom plate portion 34 in the through hole 36 or in the vicinity of the through hole 36. For example, each of the plurality of through holes 36 may be provided with a support portion that supports the supported portion 43a. An engaging portion that engages with the supported portion 43a may be provided on the inner surface of each of the plurality of through holes 36. Furthermore, for example, the supported portion 43a may be supported by the upper surface 34a of the bottom plate portion 34 in the vicinity of the through hole 36.

[0074] In the above embodiment, the detection unit 44 has a camera sensor 44a, but this is not limited to this. Fig. 9 is a cross-sectional view showing a teaching unit 220 of a second modified example. Unlike the teaching unit 120 of the first modified example, the detection unit 244 of the teaching unit 220 of the second modified example has three distance measurement sensors 244a, 244b, and 244c instead of the camera sensor 44a (see Fig. 10). The detection target unit 232 of the teaching unit 220 has two detection target plates 232a instead of the detection target plate 32a.

[0075] 9 and 10 , three distance measuring sensors 244a, 244b, and 244c are provided on the inner surface 35a of the side wall portion 35. One of the two detectable plates 232a extends along the X direction on the upper surface 41b of the upper plate portion 41. The other of the two detectable plates 232a extends along the Y direction on the upper surface 41b of the upper plate portion 41. The distance measuring sensor 244a detects the distance between one end of one detectable plate 232a in the X direction and the distance measuring sensor 244a. The distance measuring sensor 244b detects the distance between the other end of one detectable plate 232a in the X direction and the distance measuring sensor 244b. The distance measuring sensor 244c detects the distance between the other detectable plate 232a and the distance measuring sensor 244c. In this way, the three distance measuring sensors 244a, 244b, and 244c detect the two detection plates 232a, thereby detecting the positional deviation of the first unit 30 relative to the second unit 40 in the rotational direction and horizontal direction around the Z direction as the central axis.

[0076] In the above embodiment and modified example, the deceleration sensor 45 is provided on the contact plate portion 42, but this is not limiting. As shown in Fig. 8 , the deceleration sensor 45 may be provided on the first unit 30.

[0077] In the above embodiment, the area controller 110 may calibrate the detection unit 44 when performing teaching control. FIG. 11 is a cross-sectional view showing a calibration stage 500 used for calibrating the detection unit 44. The teaching control unit 50 transfers the teaching unit 20 to the calibration stage 500. The calibration stage 500 has a positioning unit 501 that positions the first unit 30 and a load port 300. When the teaching unit 20 is transferred to the calibration stage 500, the first unit 30 is separated from the second unit 40, and the first unit 30 and the second unit 40 are positioned at reference positions in the horizontal direction. In this state, the detection unit 44 may execute the detection target unit 32, thereby calibrating the detection unit 44.

[0078] 1...ceiling transport vehicle, 20, 120, 220...teaching unit, 30...first unit, 31...main body portion, 32, 232...detected portion, 34...bottom plate portion, 36...through hole, 36c...tapered portion, 40...second unit, 42...contact plate portion, 42b...lower surface (contact surface), 43a...supported portion, 43b...columnar portion, 44, 244...detection portion, 47...battery, 100...ceiling transport vehicle system, 200...container (transported object), 300...load port (transfer portion), 400...buffer (storage shelf), 402...charging mechanism.

Claims

1. A teaching unit used for teaching when transferring an object to a transfer section on which the object is placed by an overhead transport vehicle, comprising: a first unit held on the overhead transport vehicle so as to be able to rise and fall freely; and a second unit supported on the first unit so as to be able to be separated; the first unit having a main body including a bottom plate and one of a detected part and a detecting part attached to the main body, the bottom plate having at least one through hole; the second unit having at least one supported part supported by the bottom plate at or near the through hole, a contact plate part located below the bottom plate and including a contact surface that comes into contact with the transfer section, at least one columnar part that connects the supported part and the contact plate part and is able to move up and down within the through hole, and the other of the detected part and the detecting part; when the second unit is placed on the transfer section, the second unit is positioned relative to the transfer section and separated from the first unit; The detection unit detects the detected portion to detect a positional deviation of the first unit relative to the second unit in a rotational direction about a vertical axis and in a horizontal direction.

2. A teaching unit as described in claim 1, wherein when the first unit supports the second unit, the supported portion is supported by the bottom plate portion at or near the through hole, thereby guiding the second unit to a reference position relative to the first unit in the rotational direction and the horizontal direction.

3. A teaching unit as described in claim 2, wherein the bottom plate portion is provided with a plurality of through holes, and the second unit has a plurality of supported portions each supported at a predetermined position in the horizontal direction by the bottom plate portion, and a plurality of columnar portions that can move up and down in each of the plurality of through holes.

4. A teaching unit as described in claim 3, wherein each of the plurality of through holes is provided with a tapered portion so that the inner diameter of the through hole decreases as it approaches the bottom plate portion, and the plurality of supported parts are supported by the tapered portion in each of the plurality of through holes.

5. A teaching unit according to claim 1, wherein the inner surface of the through hole is provided with a plurality of inclined surfaces that face in different directions and guide the supported portion to a predetermined position in the horizontal direction.

6. A teaching unit according to claim 1, wherein the first unit has the detected part, and the second unit has the detecting part.

7. A teaching unit according to claim 6, wherein the second unit further comprises a battery that supplies power to the detection unit.

8. An overhead transport vehicle system comprising: an overhead transport vehicle that transports the transported object; and the teaching unit according to claim 1.

9. An overhead transport vehicle system comprising: an overhead transport vehicle that transports the transported object; a teaching unit according to claim 7; and a storage shelf that stores the teaching unit, wherein the storage shelf has a charging mechanism for the battery.