Rotation mechanism and ceiling transport vehicle

Abstract

This rotation mechanism is provided with a first portion and a second portion that rotates relative to the first portion about the rotation axis. One of the first portion and the second portion has a cylindrical member and a transmission member helically wound on the outer circumferential surface of the cylindrical member in a winding region exceeding one round of the outer circumferential surface. The other of the first portion and the second portion has a drive part that sends out the transmission member. The outer circumferential surface of the cylindrical member has provided thereto at least one guide member that is disposed at a position outside the winding region and on the extension of the upper end and / or lower end in the circumferential direction, and that is adjacent to the winding region in the rotation axis direction.

Description

[Technical Field]

[0001] The present disclosure relates to a rotation mechanism and an overhead transport vehicle. [Background technology]

[0002] Conventionally, for example, in an overhead transport vehicle for transporting articles, a configuration in which a rotation drive unit is provided in a transfer device is known. For example, in the overhead transport vehicle described in Patent Document 1, the lateral mechanism and the lift drive unit are rotated by a first rotation drive unit around a first vertical axis within a range of 270 degrees. This makes it possible to change the transfer position (direction) of an article using the lateral sliding movement of the lateral mechanism within the range of that rotation angle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2020 / 090288 Summary of the Invention [Problem to be solved by the invention]

[0004] To rotate a part around a vertical axis of rotation using a rotation drive unit, for example, a mechanism can be considered in which a transmission member such as a belt is wound around the outer circumferential surface of either the first part located above or the second part located below, and a drive unit for feeding the transmission member is further provided on the other of the first part or the second part. In this case, the transmission member is wound, for example, spirally around the outer circumferential surface of either the first part or the second part.

[0005] When the transmission member is wrapped around the outer periphery over a range exceeding one revolution (over a range exceeding the entire circumference of the outer periphery), one portion of the transmission member and another portion are adjacent to each other in the direction of the rotation axis. When the transmission member is advanced by the driving unit, the portion of the transmission member that contacts the driving unit temporarily separates from the outer periphery and then returns to the outer periphery. If another portion of the transmission member is located near the portion of the transmission member that has returned to the outer periphery, that portion may ride up on the other portion. This riding up may result in a decrease in rotational accuracy.

[0006] The present disclosure describes a rotation mechanism and an overhead transport vehicle that can prevent one part of a transmission member from riding on another part. [Means for solving the problem]

[0007] A rotation mechanism comprising a first part and a second part arranged below the first part and rotating relative to the first part around a rotation axis extending in the vertical direction, wherein one of the first part and the second part has a cylindrical member arranged concentrically with the rotation axis, and a transmission member that is spirally wound around the outer peripheral surface of the cylindrical member in a winding area that exceeds one circumference of the outer peripheral surface and includes upper and lower ends fixed to the cylindrical member, and the other of the first part and the second part has a drive unit that applies a driving force to the transmission member to feed the transmission member, and at least one guide member is provided on the outer peripheral surface of the cylindrical member at a position outside the winding area on an extension of at least one of the upper and lower ends in the circumferential direction and adjacent to the winding area in the rotation axis direction.

[0008] According to this rotation mechanism, by winding the power transmission member around the outer peripheral surface more than once, rotation of 360 degrees or more can be achieved. Furthermore, because the power transmission member is open-ended, it is easily removed, allowing for excellent maintainability. Furthermore, at least one guide member is adjacent to the winding area in the direction of the rotation axis. This allows the guide member to guide the power transmission member to the winding area. Therefore, it is possible to prevent one portion of the power transmission member from riding on another portion. As a result, the rotation accuracy of the rotation mechanism is improved.

[0009] The at least one guide member may include a lower guide member arranged at a position outside the winding region on an extension of the lower end in the circumferential direction, and the lower guide member may include an upwardly inclined surface that guides a portion of the transmission member near its upper end upward. The upwardly inclined surface of the lower guide member ensures smooth guidance of the transmission member and reliably prevents the portion of the transmission member near its upper end from riding over another portion of the transmission member near its lower end.

[0010] The at least one guide member may include an upper guide member arranged at a position outside the winding region on an extension of the upper end in the circumferential direction, and the upper guide member may include a downwardly inclined surface that guides a portion of the transmission member near the lower end downward. The downwardly inclined surface of the upper guide member allows smooth guidance of the transmission member and reliably prevents the portion of the transmission member near the lower end from riding over another portion of the transmission member near the upper end.

[0011] At least one guide member may be disposed adjacent to at least one of the upper end and the lower end in the circumferential direction. The region where the power transmission member tends to ride up is the region near the end of the winding region starting from the upper end or the lower end. Therefore, this configuration can more reliably prevent the power transmission member from riding up.

[0012] Another aspect of the present disclosure may provide an overhead transport vehicle including a main body having a traveling carriage including a first portion, a second portion, and a transfer device attached below the second portion for transferring an object to be transported. In this overhead transport vehicle, the transfer device can transfer an object to the side and downward, and the rotation mechanism rotates the main body about a rotation axis relative to the traveling carriage. In other words, this overhead transport vehicle improves the rotation accuracy (turning accuracy) of the main body having the transfer device, allowing objects to be loaded more accurately. [Effects of the Invention]

[0013] According to the present disclosure, it is possible to prevent one portion of the transmission member from riding on another portion, thereby improving the rotation accuracy of the rotation mechanism. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view showing an example of a traveling vehicle system according to an embodiment. [Figure 2] FIG. 2 is an exploded perspective view showing four rail units that constitute the rail assembly in FIG. 1 and a connecting member that connects them. [Figure 3] FIG. 3 is a side view showing the ceiling transport vehicle in FIG. [Figure 4] FIG. 4 is a perspective view showing the ceiling transport vehicle in FIG. [Figure 5] FIG. 5 is a perspective view showing the first section of the ceiling transport vehicle and the main body attached to the first section. [Figure 6] FIG. 6 is a perspective view showing the cylindrical member of the first portion, the transmission member, and the drive unit provided in the second portion. [Figure 7] FIG. 7 is a side view of the cylindrical member. [Figure 8] FIG. 8 is a diagram showing two guide members attached to a cylindrical member. [Figure 9] 9(a) is a perspective view of the guide member, FIG. 9(b) is a front view of the guide member, and FIG. 9(c) is a bottom view of the guide member. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, embodiments of the present disclosure 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. In the drawings, for convenience of explanation, each configuration according to the embodiment is depicted with an appropriately changed scale. Some drawings also show an XYZ Cartesian coordinate system. In the following description, this coordinate system will be referenced for ease of explanation. In the following description, one direction along a horizontal plane will be referred to as the X direction (first direction), a direction perpendicular to the X direction and along the horizontal plane will be referred to as the Y direction (second direction), and the vertical direction will be referred to as the Z direction.

[0016] As shown in FIG. 1 , an overhead traveling vehicle system (traveling vehicle system) 1 according to an embodiment is a grid system (transport system or rail-guided vehicle system) for transporting an article M by an overhead traveling vehicle (overhead transport vehicle) 2, for example, in a clean room of a semiconductor manufacturing factory. The overhead traveling vehicle system 1 includes, for example, a plurality of overhead traveling vehicles 2 (hereinafter collectively referred to as "traveling vehicles 2"), a system controller 5 that controls the plurality of traveling vehicles 2, and a track R along which the plurality of traveling vehicles 2 travel. The traveling vehicles 2 move along the track R of the overhead traveling vehicle system 1. The traveling vehicles 2 travel along the track R and transport an article M such as a FOUP (Front Opening Unified Pod) that houses a semiconductor wafer or a reticle pod that houses a reticle. The traveling vehicles 2 may also be referred to as a carriage, a transport vehicle, a transport vehicle, a traveling vehicle, or the like. The plurality of traveling vehicles 2 enables high-density transportation of the article M, improving the efficiency of transporting the article M. Note that the overhead traveling vehicle system 1 may include only one traveling vehicle 2.

[0017] The track R is installed on or near the ceiling of a building such as a clean room. The track R is installed adjacent to, for example, a processing device, a stocker (automated warehouse), etc. The processing device is, for example, an exposure device, a coater developer, a film forming device, an etching device, etc., and performs various processes on the semiconductor wafers in the article M transported by the traveling vehicle 2. The stocker stores the article M transported by the traveling vehicle 2.

[0018] The track R is arranged in a grid pattern in a plan view. The track R extends horizontally. In this embodiment, the track R is constructed by arranging a plurality of rail units 100, each having a first rail R1, a second rail R2, and an intersection rail R3, side by side in the X and Y directions. The overhead traveling vehicle system 1 includes a plurality of rail units 100 arranged side by side in the X and Y directions, and a plurality of connecting members 140 that connect the plurality of rail units 100 to one another. The plurality of rail units 100 and the plurality of connecting members 140 form a rail assembly 200. The rail assembly 200 is suspended from a ceiling or the like (not shown) by a plurality of hanging members H at the portions where the rail units 100 are connected to one another by the connecting members 140.

[0019] FIG. 2 is an exploded perspective view showing the four rail units 100 that make up the rail assembly 200 in FIG. 1 and the connecting members 140 that connect them. Each rail unit 100 is a rectangular parallelepiped (frame-shaped) member and has the same configuration. Each rail unit 100 includes two first rail members 110 arranged along the X direction, two second rail members 120 arranged along the Y direction, and four intersection rail members 130 arranged so that gaps are formed on extensions of the first rail members 110 and the second rail members 120 (i.e., at the intersections of the grid). When the rail unit 100 is viewed from above, the two parallel first rail members 110 and the two parallel second rail members 120 are arranged in a square shape, and the four intersection rail members 130 are arranged at the vertices of the square.

[0020] Each rail unit 100 is made of, for example, metal and is an integrated unit formed by molding the first rail member 110, the second rail member 120, and the intersection rail member 130. Each first rail member 110 includes a first beam portion 111 disposed at the upper end of the rail unit 100 and extending in the X direction, a first rail R1 disposed at the lower end of the rail unit 100 and extending in the X direction, and a first support wall 113 disposed between the first beam portion 111 and the first rail R1 and joined to the first beam portion 111 and the first rail R1. Each second rail member 120 includes a second beam portion 121 disposed at the upper end of the rail unit 100 and extending in the Y direction, a second rail R2 disposed at the lower end of the rail unit 100 and extending in the Y direction, and a second support wall 123 disposed between the second beam portion 121 and the second rail R2 and joined to the second beam portion 121 and the second rail R2. The multiple first beam portions 111 and the multiple second beam portions 121 form a lattice-like structure extending along the XY plane at the upper end position of the rail assembly 200. The first support wall 113 extends along the XZ plane. The second support wall 123 extends along the YZ plane.

[0021] The intersection rail member 130 includes an intersection support pillar 133 extending along the Z direction (vertical direction) at the position where the first beam portion 111 and the second beam portion 121 are joined at a right angle, and an intersection rail R3 provided at the lower end of the intersection support pillar 133.

[0022] As shown in FIG. 1 , the multiple first rails R1 each extend along the X direction. The multiple second rails R2 each extend along the Y direction. The track R is formed in a grid pattern in a plan view by the multiple first rails R1 and the multiple second rails R2. The track R is formed into multiple squares by the multiple first rails R1 and the multiple second rails R2. The intersection rail R3 is located at a portion corresponding to an intersection of the first rail R1 and the second rail R2. The intersection rail R3 is adjacent to the first rail R1 with a gap in the X direction. The intersection rail R3 is adjacent to the second rail R2 with a gap in the Y direction. The intersection rail R3 is used when the traveling vehicle 2 travels along the first rail R1, when the traveling vehicle 2 travels along the second rail R2, and when the traveling vehicle 2 travels from the first rail R1 to the second rail R2 or from the second rail R2 to the first rail R1.

[0023] Each rail unit 100 forms a square (or rectangular) track R corresponding to one square within itself. By arranging multiple rail units 100 in the X and Y directions, multiple first rails R1 extend in a row in the X direction, and multiple second rails R2 extend in a row in the Y direction. On the X-direction line, two intersection rails R3 are arranged at an interval between one first rail R1 and another first rail R1. On the Y-direction line, two intersection rails R3 are arranged at an interval between one second rail R2 and another second rail R2. The track R will be described from another perspective. Focusing on four squares consisting of two squares lined up in the X direction and two squares lined up in the Y direction, four intersection rails R3 adjacent in the X and Y directions are arranged at an interval (relative to the first rails R1) between two first rails R1 adjacent in the Y direction and two other first rails R1 adjacent in the Y direction. In addition, the same four intersection rails R3 as above are arranged at intervals (relative to the second rails R2) between two second rails R2 adjacent in the X direction and another two second rails R2 adjacent in the X direction.

[0024] In the rail assembly 200, a plurality of first rails R1, a plurality of second rails R2, and a plurality of intersection rails R3 are arranged at predetermined intervals to form a track R. A gap G corresponding to the above-mentioned interval is formed between each first rail R1 and each intersection rail R3. A gap G corresponding to the above-mentioned interval is formed between each second rail R2 and each intersection rail R3. The gap G in the track R has a constant size. Each first rail R1 includes a first running surface R1a that is flat and horizontal on its upper surface, and the running wheels 31 of the running vehicle 2 run on the first running surface R1a in the X direction (first running direction D1). Each second rail R2 includes a second running surface R2a that is flat and horizontal on its upper surface, and the running wheels 31 of the running vehicle 2 run on the second running surface R2a in the Y direction (second running direction D2). The intersection rail R3 includes an intersection running surface R3a that is flat and horizontal on its upper surface. The first running surface R1a, the second running surface R2a, and the intersection running surface R3a are all at the same height throughout the track R. The first running surface R1a, the second running surface R2a, and the intersection running surface R3a are arranged on the same or nearly the same horizontal plane.

[0025] For example, no gaps as large as the gap G are formed between the four intersecting rails R3 described above. When the traveling vehicle 2 passes through multiple rail units 100 in a straight line, the traveling wheels 31 of the traveling vehicle 2 travel on the intersecting running surfaces R3a. At that time, the traveling wheels 31 pass over any two of the four intersecting rails R3 described above. Alternatively, when the traveling vehicle 2 changes its traveling direction between the rail units 100 (changing its traveling direction by 90 degrees, i.e., when steering), the traveling wheels 31 of the traveling vehicle 2 pass over the intersecting running surfaces R3a (while changing direction).

[0026] As described above, in the rail assembly 200, a lattice-shaped track R is formed by the first rail member 110, the second rail member 120, and the intersection rail member 130. The layout of the lattice-shaped track R in the overhead traveling vehicle system 1 can be adjusted or changed as appropriate by arranging the multiple rail units 100 in any desired arrangement (including adding or deleting rail units 100).

[0027] Referring to FIG. 2, the connection structure of the rail units 100 using the connecting members 140 will be described. As shown in FIG. 2, each connecting member 140 includes an upper connecting member 141 and a lower connecting member 142. The upper connecting member 141, which is a horizontally extending plate or frame, is attached to the upper surface of one of the four corners of a plurality of (typically four) rail units 100. The upper connecting member 141 abuts near the intersection of the first beam portion 111 and the second beam portion 121 of each rail unit 100. The lower connecting member 142, which is a horizontally extending plate or frame, supports the lower surface of one of the four corners of a plurality of (typically four) rail units 100. The lower connecting member 142 abuts against the intersection rail R3 of each rail unit 100.

[0028] A rod-shaped hanging member H extending in the vertical direction penetrates the upper connecting member 141 and the lower connecting member 142. The upper connecting member 141 and / or the lower connecting member 142 are fixed to the rail units 100 by fastening members (not shown) or the like, thereby connecting the rail units 100 to each other. Note that spaces 100e extending in the Z direction are formed between the rail units 100, and spaces R3e extending in the Z direction are formed between four intersection rails R3 adjacent in the X and Y directions (central portions in plan view). The hanging member H is inserted into the spaces 100e and R3e, and the upper connecting member 141 and / or the lower connecting member 142 are fixed to the hanging member H.

[0029] The overhead traveling vehicle system 1 includes a communication system (not shown). The communication system is used for communication between the traveling vehicles 2 and the system controller 5. The traveling vehicles 2 and the system controller 5 are connected to each other so as to be able to communicate with each other via the communication system.

[0030] Next, the configuration of the traveling vehicle 2 will be described with reference to Figures 1, 3, and 4. As shown in Figures 1 and 3, the traveling vehicle 2 is provided so as to be able to travel along a track R. The traveling vehicle 2 has a traveling bogie 20 that travels on the track R, and a main body 10 that is attached to the bottom of the traveling bogie 20 and is rotatable relative to the traveling bogie 20. The traveling bogie 20 includes a bogie unit 50, for example, having a rectangular shape, that is arranged below the track R, running sections 30 that are provided at the four corners of the bogie unit 50 in a plan view and protrude upward from the bogie unit 50, and four wheel turning mechanisms 40 that turn each of the four traveling wheels 31 of the running section 30 relative to the bogie unit 50. A bogie controller (control unit) 8 is provided inside the bogie unit 50.

[0031] The main body 10 is disposed below the track R. As shown in FIGS. 3 and 4, the main body 10 has a main body frame 12 formed, for example, in a cylindrical shape. The main body frame 12 includes a disk-shaped top plate 12a and a cylindrical frame 12b hanging down from the periphery of the top plate 12a, and has a shape with an open bottom. The main body 10 is formed to have dimensions that fit into one square on the track R (see FIG. 1) in a plan view. A traveling vehicle 2 can pass another traveling vehicle 2 traveling on an adjacent first rail R1 or second rail R2. The main body 10 includes a transfer device 18 disposed inside the main body frame 12. The transfer device 18 has, for example, a rectangular shape in a plan view. The cylindrical frame 12b is open in a portion in the circumferential direction. The range in which the open portion (notch) is formed is large enough to allow the transfer device 18 to pass through. When moving horizontally, the transfer device 18 passes through the opening in the cylindrical frame 12b.

[0032] The main body 10 is attached to the bottom of the bogie unit 50 and is rotatable around a rotation axis L10 in the Z direction relative to the bogie unit 50. Traveling wheels 31 provided at the four corners of the bogie unit 50 are placed on the track R (on the first travel surface R1a, the second travel surface R2a, or the intersection travel surface R3a). The bogie unit 50 is suspended from the track R via the four traveling wheels 31 and four wheel swivel mechanisms 40. The four traveling wheels 31 allow the bogie unit 50 and the main body 10 to be stably suspended, and also allow the main body 10 to travel stably. In other words, the traveling vehicle 2 is suspended and supported by the traveling wheels 31 that travel along the track R, and moves below the track R.

[0033] The transfer device 18 moves horizontally relative to the main body 10 to transfer an article M between the load port (mounting table). The transfer device 18 is provided below the top plate 12a of the main body frame 12. The main body 10, including the transfer device 18, can rotate about a rotation axis L10 by a drive unit (described in detail below) provided on the top plate 12a. The transfer device 18 has an article holding unit 13 that holds the article M below the track R, an elevation drive unit 14 that raises and lowers the article holding unit 13 in the vertical direction, and a slide mechanism 11 that slides the elevation drive unit 14 in the horizontal direction. The slide mechanism 11 is held on the underside of the top plate 12a. A rotation drive unit 16 is provided between the slide mechanism 11 and the elevation drive unit 14 to rotate the elevation drive unit 14 about the rotation axis L14 relative to the slide mechanism 11. The rotation drive unit 16 is provided below the slide mechanism 11, and the lift drive unit 14 is provided below the rotation drive unit 16. The article holder 13 is provided below the lift drive unit 14 via a plurality of hanging members 13b. The load port is the transfer destination or source of the traveling vehicle 2, and is the point where the article M is handed over to or from the traveling vehicle 2.

[0034] The article holding unit 13 holds the article M by suspending it by gripping the flange portion Ma of the article M. The article holding unit 13 is, for example, a chuck having claw portions 13a that can move horizontally. The article holding unit 13 holds the article M by inserting the claw portions 13a below the flange portion Ma of the article M and raising the article holding unit 13. The article holding unit 13 is connected to a hanging member 13b such as a wire or a belt.

[0035] Lifting drive unit 14 is, for example, a hoist, and lowers article holding unit 13 by paying out hanging member 13b, and raises article holding unit 13 by reeling in hanging member 13b. Lifting drive unit 14 is controlled by cart controller 8, and lowers or raises article holding unit 13 at a predetermined speed. Lifting drive unit 14 is also controlled by cart controller 8, and maintains article holding unit 13 at a target height.

[0036] The slide mechanism 11 has multiple movable plates arranged in a stacked manner, for example, in the Z direction. By rotating the main body 10, the slide mechanism 11 moves the rotation drive unit 16, the lift drive unit 14, and the article holder 13 attached to the lowest movable plate in any direction within a horizontal plane. The movement direction of the movable plates in the slide mechanism 11 is determined by the rotation angle of the main body 10 relative to the cart unit 50. In the main body 10, the orientation of the transfer device 18 and the main body frame 12 is set so that the movement direction of the movable plates coincides with the position of the opening of the cylindrical frame 12b.

[0037] The rotation drive unit 16 includes, for example, an electric motor, and rotates the lift drive unit 14 (and the article holder 13) within a predetermined angular range around a rotation axis L14 extending vertically. The angle at which the rotation drive unit 16 can rotate is, for example, any angle equal to or less than 180 degrees, but the upper limit is not limited to 180 degrees. The rotation drive unit 16 can orient the article holder 13 (or the article M held by the article holder 13) that is laterally extended in a desired direction. The slide mechanism 11 and the rotation drive unit 16 are controlled by the cart controller 8. Note that the lift drive unit 14 can be rotated by the rotation drive unit 16 even when the movable plate of the slide mechanism 11 is stored without moving (the state shown by the solid line in FIG. 3). In this case, for example, the rotation axis L14 of the lift drive unit 14 coincides with the rotation axis L10 of the main body 10.

[0038] The carriage unit 50 has a cylindrical support member (cylindrical member) 52 at its lower end. The top plate 12a of the main body frame 12 is rotatably attached to the underside of the support member 52. For example, a drive unit such as an electric motor (described in detail below) is provided on the top plate 12a. When the driving force of the drive unit is transmitted to the support member 52, the main body frame 12 rotates around a rotation axis L10 extending vertically relative to the carriage unit 50. The main body frame 12 can rotate at an angle of, for example, 360 degrees or more and 540 degrees or less, but the upper limit is not limited to 540 degrees. A slide mechanism 11 is attached to the underside of the top plate 12a, and the top plate 12a supports the slide mechanism 11. The main body frame 12 and the transfer device 18 are integrated, and the main body frame 12 and the transfer device 18 rotate together. The traveling vehicle 2 can transfer an article M to or from a load port using the transfer device 18.

[0039] A cover (not shown) may be attached to the outer surface of the cylindrical frame 12b. In this case, the cover surrounds the transfer device 18 and the article M held by the transfer device 18. The cover is cylindrical with an open bottom end, and has a cutout at the portion where the movable plate of the slide mechanism 11 protrudes (the above-mentioned open portion).

[0040] The traveling unit 30 has four traveling wheels 31. Each traveling wheel 31 is provided with two auxiliary wheels 32. As shown in FIG. 4, the traveling wheels 31 are provided at the four corners of the bogie unit 50 so as to protrude upward from the top cover 51. Each traveling wheel 31 is rotatable around a horizontal or nearly horizontal axle axis along the XY plane. A traveling drive motor 33 is provided on the rotation axis of each traveling wheel 31. Each traveling wheel 31 is driven to rotate by the driving force of the traveling drive motor 33. The traveling drive motor 33 is configured to be able to switch between forward and reverse rotation, for example. Each traveling wheel 31 rolls on the track R. Each traveling wheel 31 rolls on the running surfaces R1a, R2a, and R3a of the first rail R1, the second rail R2, and the intersection rail R3, respectively, to cause the traveling vehicle 2 to travel. It should be noted that the present invention is not limited to a configuration in which all of the four traveling wheels 31 are rotationally driven by the driving force of the traveling drive motor 33, and a configuration in which only some of the four traveling wheels 31 are rotationally driven may also be adopted.

[0041] Four wheel swivel mechanisms 40 are fixed to a bogie frame (not shown) inside the bogie unit 50, and a pedestal 34 is connected to each wheel swivel mechanism 40 via the pivot shaft of the wheel swivel mechanism 40. A running wheel 31, two auxiliary wheels 32, and one running drive motor 33 are attached to the pedestal 34 via a connecting portion 35 and a support member 36. For example, a square-shaped top cover 51 is provided on the top surface of the housing 53, and the pedestal 34 is disposed in notches formed in the four corners of the top cover 51. The connecting portion 35, running wheels 31, auxiliary wheels 32, and running drive motor 33 are disposed above the top cover 51.

[0042] As shown in FIGS. 3 and 4 , the connecting portion 35 connects the bogie unit 50 (more specifically, the wheel swivel mechanism 40 fixed inside the bogie unit 50) and the running wheels 31. With this connecting structure, the bogie unit 50 and the main body 10 are positioned below the track R and suspended from the running portion 30. The connecting portion 35 is formed to a thickness that allows it to pass through the gap G between the first rail R1 and the intersection rail R3 and between the second rail R2 and the intersection rail R3. The support member 36 is provided on the upper portion of the connecting portion 35 and rotatably supports the rotation shaft of the running wheels 31 and the rotation shaft of the auxiliary wheels 32. The support member 36 maintains the relative positions of the running wheels 31 and the auxiliary wheels 32.

[0043] As shown in FIG. 4, the traveling wheels 31 are provided so as to be rotatable about rotation axes L30 extending in the vertical direction. The four rotation axes L30 are arranged at the vertices of a square in a plan view, and the rotation axis L10 is arranged at the center of the rotation axes L30. In other words, the four rotation axes L30 are arranged at positions that are four-fold symmetrical with respect to the rotation axis L10 of the main body 10. In a plan view, the positions of the traveling wheels 31 and the rotation axes L30 are different (displaced). The traveling wheels 31 are rotated by the wheel rotation mechanism 40, and as a result, the traveling direction of the traveling vehicle 2 can be changed.

[0044] The auxiliary wheels 32 are arranged one in front of and one behind the running wheel 31 in the traveling direction. Each auxiliary wheel 32 is rotatable around a horizontal or nearly horizontal axle axis along the XY plane. The lower ends of the auxiliary wheels 32 are set, for example, to be higher than the lower ends of the running wheels 31. Therefore, when the running wheels 31 are traveling on the traveling surfaces R1a, R2a, and R3a, the auxiliary wheels 32 do not come into contact with the traveling surfaces R1a, R2a, and R3a. Furthermore, when the running wheels 31 pass through the gaps G between the first rail R1 and the intersection rail R3 and between the second rail R2 and the intersection rail R3, the auxiliary wheels 32 come into contact with auxiliary members (not shown) provided on the first rail R1 and the second rail R2, thereby preventing the running wheels 31 from sagging. It should be noted that the present invention is not limited to providing two auxiliary wheels 32 for one running wheel 31; for example, one auxiliary wheel 32 may be provided for one running wheel 31, or no auxiliary wheel 32 may be provided.

[0045] The four wheel swivel mechanisms 40 are disposed, for example, at the four corners of the housing 53 of the bogie unit 50. Each wheel swivel mechanism 40 includes a steering motor 43 and a driving force transmission unit 42 provided between the steering motor 43 and the running wheels 31. The driving force transmission unit 42 is fixed to a bogie frame (not shown) within the bogie unit 50. The driving force transmission unit 42 is connected to the base 34 via a swivel shaft. Each wheel swivel mechanism 40 rotates the base 34, the connecting unit 35, the support member 36, the running wheels 31, the auxiliary wheels 32, and the running drive motor 33 together around the swivel axis L30. With the running vehicle 2 positioned at the center of each rail unit 100, each running wheel 31 is rotated 90 degrees around the swivel axis L30. This causes the running wheels 31 to rotate on the intersection rail R3. This allows the running vehicle 2 to turn. Turning refers to switching from a first state in which the traveling vehicle 2 travels in a first traveling direction D1 to a second state in which the traveling vehicle 2 travels in a second traveling direction D2, or from the second state in which the traveling vehicle 2 travels in the second traveling direction D2 to the first state in which the traveling vehicle 2 travels in the first traveling direction D1. The traveling vehicle 2 turns, for example, when the traveling vehicle 2 is stopped. The traveling vehicle 2 may also turn when the traveling vehicle 2 is stopped but the article M is moving (for example, turning). The driving of the wheel turning mechanism 40 is controlled by the carriage controller 8.

[0046] As described above, a gap G is formed in the track R. When the traveling vehicle 2 travels on the first rail R1 and crosses the second rail R2, or when the traveling vehicle 2 travels on the second rail R2 and crosses the first rail R1, a part of the traveling vehicle 2 (more specifically, for example, the connecting portion 35) passes through the gap G.

[0047] Note that a guide roller that abuts against the side of the crossing rail R3 may be provided between the traveling wheel 31 and the wheel turning mechanism 40 (for example, near the connecting portion 35). The guide roller prevents the traveling carriage 20 (traveling vehicle 2) from shifting position relative to the track R.

[0048] The traveling vehicle 2 is equipped with a position detection unit (not shown) that detects position information. The position detection unit detects the current position of the traveling vehicle 2 by detecting a position marker that indicates position information provided on the track R, for example. The position detection unit detects the position marker in a non-contact manner.

[0049] The bogie controller 8 performs overall control of the traveling vehicle 2. The bogie controller 8 is a computer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), etc. The bogie controller 8 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 bogie controller 8 may also be configured as hardware including electronic circuits, etc. The bogie controller 8 may be configured as a single device or multiple devices. When configured as multiple devices, these devices are connected via a communication network such as the Internet or an intranet to logically construct a single bogie controller 8. The bogie controller 8 is provided in the bogie unit 50, for example.

[0050] The carriage controller 8 controls the traveling of the traveling vehicle 2 based on the transport command. The carriage controller 8 controls the traveling of the traveling vehicle 2 by controlling the traveling drive motor 33, the steering motor 43, etc. The carriage controller 8 controls, for example, the traveling speed, operations related to stopping, and operations related to changing direction. The carriage controller 8 controls the transfer operation of the traveling vehicle 2 based on the transport command. The carriage controller 8 controls the transfer direction of the transfer device 18 by controlling the rotation (turning) of the main body 10 (main body frame 12 and transfer device 18). The carriage controller 8 controls the transfer operation of the traveling vehicle 2 by controlling the transfer device 18, etc. The carriage controller 8 controls the operation of the object grabber that grasps the item M to be placed at a specified load port, and the unloading operation that lowers the held item M into the specified load port.

[0051] The system controller 5 is a computer including a CPU, a ROM, a RAM, etc. The system controller 5 can be configured as software in which a program stored in the ROM is loaded into the RAM and executed by the CPU, for example. The system controller 5 may also be configured as hardware including electronic circuits, etc. The system controller 5 may be configured as a single device or multiple devices. When the system controller 5 is configured as multiple devices, these devices are connected via a communication network such as the Internet or an intranet to logically form a single system controller 5. At least some of the various controls of the system controller 5 may be executed by the bogie controller 8.

[0052] The system controller 5 selects one of a plurality of traveling vehicles 2 capable of transporting the item M, and assigns a transport command to the selected traveling vehicle 2. The transport command includes a travel command to cause the traveling vehicle 2 to travel to the load port, and a command to grab the item M placed at the load port or a command to unload the held item M to the load port.

[0053] Next, with reference to Figures 5 and 6, a mechanism for rotating (turning) the main body unit 10 provided in the traveling vehicle 2 will be described in detail. The traveling vehicle 2 is provided with a rotation mechanism 300 (see Figure 6) for rotating the main body unit 10. The rotation mechanism 300 includes a bogie frame lower part (first part) 50a that is part of the bogie unit 50, and a main body frame (second part) 12 that is arranged below the bogie frame lower part 50a. The rotation mechanism 300 is a mechanism that rotates the main body frame 12 relative to the bogie frame lower part 50a. The main body frame 12 rotates relative to the bogie frame lower part 50a around a rotation axis L10 that extends in the vertical direction.

[0054] As shown in FIG. 5, the bogie frame lower portion 50a has a support member (cylindrical member) 52 that forms the lower end of the bogie frame. The support member 52 is arranged concentrically with the rotation axis L10. The top plate portion 12a of the horizontally extending main frame 12 has, for example, a circular recess 12c formed concentrically with the rotation axis L10 and a central hole 12e formed in the center of the recess 12c (at the position where the rotation axis L10 passes). The bogie frame and the top plate portion 12a are connected by, for example, a shaft that passes through the central hole 12e. Furthermore, a guide member (e.g., a protrusion) is provided on either the support member 52 or the top plate portion 12a, and a guided portion (e.g., a recess) is provided on the other of the support member 52 or the top plate portion 12a so that the top plate portion 12a rotates around the rotation axis L10 relative to the support member 52. For example, a part of the bogie frame lower part 50a may fit into the recess 12c. With this configuration, the main body frame 12 is provided rotatably while being suspended from the bogie frame lower part 50a.

[0055] As shown in FIG. 6, the bogie frame lower portion 50a has a power transmission member 66 wound around the outer peripheral surface 52a of the support member 52. The power transmission member 66 is, for example, a belt having a flat cross section. The cross section of the power transmission member 66 is long in the direction along the rotation axis L10 and short in the radial direction centered on the rotation axis L10. In other words, the long side direction of the cross section of the power transmission member 66 is parallel to the rotation axis L10, and the short side direction (thickness direction) of the cross section of the power transmission member 66 is parallel to the radial direction. The power transmission member 66 is wound spirally over an area exceeding one circumference of the outer peripheral surface 52a.

[0056] A more detailed explanation will be given with reference to FIG. 7. FIG. 7 is a side view of the support member 52. As shown in FIG. 7, a groove-like portion 55 is formed around the entire periphery of the outer peripheral surface 52a of the support member 52. The transmission member 66 is disposed in this groove-like portion 55. As shown in FIGS. 6 and 7, an upper fixing groove 57A for fixing an upper end portion 67A of the transmission member 66 and a lower fixing groove 57B for fixing a lower end portion 67B of the transmission member 66 are formed in the outer peripheral surface 52a. The upper fixing groove 57A and the lower fixing groove 57B are both formed in the middle of the groove-like portion 55. The upper fixing groove 57A and the lower fixing groove 57B are, for example, located at different positions in the circumferential direction and also at different positions in the direction of the rotation axis L10. In the direction of the rotation axis L10, the upper fixing groove 57A is formed in the upper part of the outer circumferential surface 52a, and the lower fixing groove 57B is formed in the lower part of the outer circumferential surface 52a.

[0057] As shown in FIG. 6, the upper end 67A of the power transmission member 66 is disposed at the upper portion of the outer peripheral surface 52a, and the lower end 67B of the power transmission member 66 is disposed at the lower portion of the outer peripheral surface 52a. The power transmission member 66 is wound around the outer peripheral surface 52a over a length that is one full turn (360 degrees) plus a predetermined angular range (e.g., 60 to 90 degrees). The predetermined angular range is the range in which the power transmission members 66 overlap each other in a plan view (as viewed from the direction of the rotation axis L10). Within this range, the power transmission members 66 are arranged substantially parallel to each other. The predetermined angular range may be less than 180 degrees or may be greater than or equal to 180 degrees. The power transmission member 66 is spirally wound in a winding region A that extends from the upper end 67A (upper fixing groove 57A) to the lower end 67B (lower fixing groove 57B) over a range of approximately one and one-third to one-half turns (less than two turns in total). That is, the winding region A is a spiral region connecting the upper fixing groove 57A and the lower fixing groove 57B, and is the region through which the transmission member 66 originally passes (in a normal state).

[0058] As shown in FIG. 7, the winding region A includes the upper edge 55a of the power transmission member 66, where the portion 66a near the upper end 67A is located. The winding region A also includes the lower edge 55b of the power transmission member 66, where the portion 66b near the lower end 67B is located. The upper edge 55a and the lower edge 55b are adjacent to each other in the direction of the rotation axis L10. The winding region A includes a single arc-shaped inclined portion (most of which is hidden behind the curve in FIG. 7) connecting the upper edge 55a and the lower edge 55b. Because the power transmission member 66 is wound spirally, the upper edge 55a and the lower edge 55b are also slightly inclined spirally. The groove-shaped portion 55 of the outer peripheral surface 52a described above has a height (length in the direction of the rotation axis L10) slightly greater than twice the length of the long side of the cross section of the power transmission member 66. As a result, in the range where the upper edge 55a and the lower edge 55b are adjacent, i.e., the range where the transmission members 66 are arranged in parallel, the gap between the transmission members 66 is shorter than the length of the long side of the cross section of the transmission members 66.

[0059] As shown in FIG. 6, the main frame 12 has a drive unit 60 that applies a driving force to the transmission member 66 to feed the transmission member 66. For example, the diameter of the top plate 12a is larger than the diameter of the support member 52 (see FIG. 5). The drive unit 60 is disposed, for example, on the radially outer side of the support member 52. The drive unit 60 includes a drive motor 63 attached to the back side of the top plate 12a, one drive pulley 61 fixed to a drive shaft 63a of the drive motor 63, and a pair of auxiliary rollers 62 provided on both sides of the drive pulley 61. Teeth are formed on the entire back surface of the transmission member 66 (the surface that abuts against the outer peripheral surface 52a, i.e., the surface facing radially inward). The transmission member 66 is a timing belt. Furthermore, teeth that mesh with the teeth of the transmission member 66 are formed on the outer peripheral surface of the drive pulley 61. The drive pulley 61 is a timing pulley. A portion of the transmission member 66 is pulled out, and the pulled-out portion 66f is wound around the drive pulley 61. A pair of auxiliary rollers 62 press the base of the pulled-out portion 66f. The rotation axis L61 of the drive pulley 61 is parallel to the rotation axis L10, for example. The rotation axes of the pair of auxiliary rollers 62 are also parallel to the rotation axis L10. The drive shaft 63a passes through the top plate portion 12a in a state where it can rotate freely relative to the top plate portion 12a. The drive motor 63 is controlled by the cart controller 8. The drive unit 60 uses the rotational driving force of the drive motor 63 and the drive pulley 61 to feed the transmission member 66 in the circumferential direction (strictly speaking, in the direction along the spiral).

[0060] In the rotation mechanism 300, the drive pulley 61 rotates around the rotation axis L61, which pulls the transmission member 66 and rotates the main body frame 12 relative to the bogie frame lower part 50a.

[0061] As shown in FIGS. 6 to 8, two guide members 70 are fixed to the outer peripheral surface 52a of the support member 52. One of the guide members 70, an upper guide member 70A, is disposed at a position outside the winding region A on an extension of the upper end portion 67A in the circumferential direction (upper mounting portion 58A on the left side of the upper fixing groove 57A in FIG. 8). The other guide member 70, a lower guide member 70B, is disposed at a position outside the winding region A on an extension of the lower end portion 67B in the circumferential direction (lower mounting portion 58B on the right side of the lower fixing groove 57B in FIG. 8). In this way, the upper guide member 70A and the lower guide member 70B are each attached to a portion of the outer peripheral surface 52a other than the spirally formed winding region A.

[0062] 6, the inclined surface 73a (see FIG. 9) of the upper guide member 70A is provided so as to contact the upper surface of the portion 66d of the transmission member 66 in the direction of the rotation axis L10. The inclined surface 73a of the lower guide member 70B is provided so as to contact the lower surface of the portion 66c of the transmission member 66 in the direction of the rotation axis L10.

[0063] As shown in FIG. 8, the upper guide member 70A and the lower guide member 70B share the same (identical) component, the guide member 70. However, the orientations in which they are attached to the outer peripheral surface 52a are different. As shown in FIGS. 9(a) and 9(c), the upper guide member 70A includes a fixing portion 71 provided at one end thereof and a guide portion 73 extending in an arc from the fixing portion 71. The fixing portion 71 has, for example, two holes 72. The fixing portion 71 is fixed to the upper fixing groove 57A or the lower fixing groove 57B using these holes 72 and screws (not shown). The radius of curvature of the guide portion 73 is approximately the same as the radius of curvature of the outer peripheral surface 52a of the support member 52 (the bottom surface of the groove portion 55). Therefore, the guide portion 73 extends along the support member 52 (the bottom surface of the groove portion 55).

[0064] As shown in FIGS. 6 and 8 , the upper guide member 70A is disposed adjacent to the upper end 67A in the circumferential direction. The lower guide member 70B is disposed adjacent to the lower end 67B in the circumferential direction. In order to position each guide member 70 close to the end of the transmission member 66, the mounting portion of each guide member 70 is set in the same area (or in areas adjacent to each other) as the mounting portions (fixing portions) of the upper end 67A and the lower end 67B. More specifically, the upper fixing groove 57A is provided with a recess and / or hole for fixing the upper end 67A of the transmission member 66, and is also provided with a recess and / or hole for fixing the fixing portion 71 of the upper guide member 70A. The lower fixing groove 57B is provided with a recess and / or hole for fixing the lower end 67B of the transmission member 66, and is also provided with a recess and / or hole for fixing the fixing portion 71 of the lower guide member 70B. The upper fixing groove 57A and the lower fixing groove 57B may each be formed flat to facilitate fixing the transmission member 66 and the guide member 70. As a result, the guide portion 73 of the upper guide member 70A is disposed on the upper mounting portion 58A adjacent to the upper fixing groove 57A, and the guide portion 73 of the lower guide member 70B is disposed on the lower mounting portion 58B adjacent to the lower fixing groove 57B.

[0065] As shown in FIG. 9(b), an inclined surface 73a whose height in the direction of the rotation axis L10 gradually changes is formed on one end surface of the guide portion 73 of the guide member 70 in the direction of the rotation axis L10 (see FIG. 6). That is, as shown in FIG. 6, the upper guide member 70A includes an inclined surface 73a (a downward inclined surface) that guides the portion 66d of the transmission member 66 near the lower end 67B downward. The lower guide member 70B also includes an inclined surface 73a (an upward inclined surface) that guides the portion 66c of the transmission member 66 near the upper end 67A upward. In this specification, when the term "portion near 'something'" is used, such as "portion 66d near the lower end 67B" or "portion 66c near the upper end 67A," it indicates that the portion is located near one of the ends. That is, "near 'something'" means "relatively close to 'something'."

[0066] The upper guide member 70A prevents the portion 66d of the transmission member 66 from riding up onto the other portion 66a when the drive pulley 61 pulls in the portion 66d of the transmission member 66 and the portion 66d lands on the outer peripheral surface 52a. The lower guide member 70B prevents the portion 66c of the transmission member 66 from riding up onto the other portion 66b when the drive pulley 61 pulls in the portion 66c of the transmission member 66 and the portion 66c lands on the outer peripheral surface 52a. This guides the transmission member 66 (when it lands) so that the upper end 67A and the lower end 67B of the transmission member 66, as well as the respective portions of the transmission member 66, are aligned in the correct positions without overlapping.

[0067] According to the rotation mechanism 300 of this embodiment, by winding the power transmission member 66 more than once around the outer circumferential surface 52a, rotation of 360 degrees or more can be achieved. Furthermore, because the power transmission member 66 is open-ended, it is easily removed, achieving excellent maintainability. Furthermore, at least one guide member 70 is adjacent to the winding region A in the direction of the rotation axis L10. This allows the guide member 70 to guide the power transmission member 66 into the winding region A. Therefore, one portion of the power transmission member 66 is prevented from riding on another portion. As a result, misalignment of the rotation mechanism 300 is prevented, improving rotation accuracy. Furthermore, because the power transmission member 66 is open-ended, it can be replaced or adjusted simply by releasing the upper end 67A and the lower end 67B, which are located at both ends. Therefore, replacement or adjustment of the power transmission member 66 is easy, achieving excellent maintainability. According to the rotation mechanism 300, the transmission member 66 is advanced to an extent that it goes more than one revolution around the outer circumferential surface 52a of the support member 52, thereby enabling rotation by the drive unit 60. As a result, rotation of 360 degrees or more (relative rotation) can be realized.

[0068] The lower guide member 70B includes an inclined surface 73a (upward inclined surface) that guides upward a portion 66c of the transmission member 66 that is close to the upper end 67A. The inclined surface 73a of the lower guide member 70B allows smooth guidance of the transmission member 66 and reliably prevents the portion 66c of the transmission member 66 that is close to the upper end 67A from riding up on the other portion 66b of the transmission member 66 that is close to the lower end 67B.

[0069] The upper guide member 70A includes an inclined surface 73a (downward inclined surface) that guides downward the portion 66d of the transmission member 66 that is close to the lower end 67B. The inclined surface 73a of the upper guide member 70A allows the transmission member 66 to be smoothly guided, and reliably prevents the portion 66d of the transmission member 66 that is close to the lower end 67B from riding up on the other portion 66a of the transmission member 66 that is close to the upper end 67A.

[0070] The upper guide member 70A and the lower guide member 70B are disposed adjacent to the upper end 67A and the lower end 67B in the circumferential direction, respectively. The area where the power transmission member 66 tends to ride up is the area near the end of the winding area A that starts from the upper end 67A or the lower end 67B. Therefore, with this configuration, the power transmission member 66 is more reliably prevented from riding up.

[0071] In the traveling vehicle 2 of the overhead traveling vehicle system 1, the transfer device 18 allows the article M to be transferred sideways and downwards, and the rotation mechanism 300 allows the main body 10 to rotate about the rotation axis L10 relative to the traveling carriage 20. In other words, with this traveling vehicle 2, the rotation accuracy (turning accuracy) of the main body 10 having the transfer device 18 is improved, allowing the article M to be placed more accurately. Furthermore, by preventing riding up, variation in the trajectory of the transmission member 66 when the main body 10 rotates is reduced, which also contributes to improved stopping accuracy.

[0072] Although the embodiments of the present disclosure have been described above, the present invention is not limited to the above embodiments. The upper guide member 70A is not limited to being disposed adjacent to the upper end portion 67A, but may be spaced apart in the circumferential direction from the upper end portion 67A. The lower guide member 70B is not limited to being disposed adjacent to the lower end portion 67B, but may be spaced apart in the circumferential direction from the lower end portion 67B. For example, either the upper guide member 70A or the lower guide member 70B may be omitted. Even in such a modified example, the guide member 70 is disposed at a position outside the winding region A (a position where the spiral transmission member 66 would not normally pass).

[0073] The inclined surface may be omitted from the guide member 70. The specific configuration of the guide member is not limited to the above embodiment. For example, the guide member can be realized in a shape other than a long, arc-shaped shape.

[0074] In the above embodiment, an example has been described in which the rotation axis L61 of the drive pulley 61 extends in the vertical direction, but the rotation axis L61 of the drive pulley 61 may be tilted in accordance with the tilt of the transmission member 66. This reduces slippage of the transmission member 66 on the drive pulley 61 and reduces wear of the transmission member 66. The transmission member is not limited to a belt.

[0075] The rotation mechanism may allow the first portion disposed above to rotate relative to the second portion disposed below. In the above embodiment, the bogie frame lower portion 50a, which is the first portion, includes the support member 52, which is a cylindrical member, and the transmission member 66, and the main body frame 12, which is the second portion, includes the drive unit 60. Alternatively, a configuration may be adopted in which the second portion disposed below includes the cylindrical member and the transmission member, and the first portion disposed above includes the drive unit. In this case, the second portion may rotate relative to the first portion, or the first portion may rotate relative to the second portion. In these modified examples, specific mechanisms may be the same as those in the above embodiment.

[0076] In the above embodiment, the four turning axes L30 of the traveling unit 30 and the wheel turning mechanism 40 are arranged at the vertices of a square in a plan view, but the turning axes L30 do not have to be arranged in a square shape. In a plan view, the position of the traveling wheels 31 and the position of the turning axes L30 may coincide.

[0077] In the above embodiment, the case where the running wheels 31 rotate on the intersection rail R3 has been described, but when turning by each wheel turning mechanism 40, each running wheel 31 may transfer from the first running surface R1a to the second running surface R2a, or from the second running surface R2a to the first running surface R1a.

[0078] In the above embodiment, the traveling vehicle is an overhead transport vehicle, but the traveling vehicle may be a rail-guided vehicle that travels on rails (tracks) provided on the ground.

[0079] In the above embodiment, a grid system is used as the overhead traveling vehicle system 1, but the overhead traveling vehicle system 1 is not limited to a grid system. For example, an AGV (Automated Guided Vehicle) may be used as the transport system, or various known systems that travel on a grid-like traveling path may be used. In the above embodiment, the traveling vehicle 2 holds the article M below the track R, but the traveling vehicle 2 may also hold the article M above the track R.

[0080] The constituent features of one aspect of the present invention are described as follows. [1] A rotation mechanism including a first portion and a second portion disposed below the first portion and configured to rotate relative to the first portion around a rotation axis extending in a vertical direction, One of the first portion and the second portion is a cylindrical member arranged concentrically with the rotation axis; a transmission member that is spirally wound around the outer circumferential surface of the cylindrical member in a winding region that exceeds one circumference of the outer circumferential surface, and that includes an upper end portion and a lower end portion that are fixed to the cylindrical member; The other of the first portion and the second portion is a drive unit that applies a driving force to the transmission member to feed the transmission member, A rotation mechanism in which at least one guide member is provided on the outer peripheral surface of the cylindrical member, the guide member being positioned outside the winding area on an extension of at least one of the upper end and the lower end in the circumferential direction and adjacent to the winding area in the rotation axis direction. [2] the at least one guide member includes a lower guide member that is disposed at a position outside the winding region on an extension of the lower end portion in the circumferential direction, The rotation mechanism according to [1], wherein the lower guide member includes an upwardly inclined surface that guides a portion of the transmission member near the upper end portion upward. [3] the at least one guide member includes an upper guide member disposed at a position outside the winding region on an extension of the upper end portion in the circumferential direction, The rotation mechanism according to [1] or [2], wherein the upper guide member includes a downwardly inclined surface that guides a portion of the transmission member near the lower end portion downward. [4] The rotation mechanism according to any one of [1] to [3], wherein the at least one guide member is disposed adjacent to at least one of the upper end portion and the lower end portion in the circumferential direction. [5] a traveling carriage including the first portion; a main body having the second portion and a transfer device attached below the second portion to transfer an object to be transported; The overhead transport vehicle, wherein the rotation mechanism according to any one of [1] to [4] rotates the main body relative to the traveling carriage around the rotation axis. [Explanation of symbols]

[0081] 1...Overhead traveling vehicle system (traveling vehicle system), 2...Overhead traveling vehicle (overhead transport vehicle), 5...System controller, 8...Cart controller (control unit), 10...Main body, 12...Main body frame (second part), 18...Transfer device, 20...Traveling vehicle, 30...Traveling unit, 33...Travel drive motor, 35...Connecting unit, 40...Wheel swivel mechanism, 43...Steering motor, 50...Cart unit, 50a...Cart frame lower part (first part), 52...Support member (cylindrical member), 52a...Outer periphery, 58A...Upper mounting part, 58B...Lower mounting part, 60...Drive unit, 66...Transmission member, 66c...Part (near the upper end), 66d...(near the lower end) a part of the rail, 67A...upper end portion, 67B...lower end portion, 70...guide member, 70A...upper guide member, 70B...lower guide member, 100...rail unit, 110...first rail member, 113...first support wall, 120...second rail member, 123...second support wall, 130...intersection rail member, 140...connecting member, 200...rail assembly, 300...rotating mechanism, A...winding area, D1...first running direction, D2...second running direction, G...spacing, H...hanging member, M...article, R...track, R1...first rail, R2...second rail, R3...intersection rail, R1a...first running surface, R2a...second running surface, R3a...intersection running surface.

Claims

1. A rotation mechanism including: a first portion; and a second portion disposed below the first portion and configured to rotate relatively to the first portion around a rotation axis extending in a vertical direction, One of the first portion and the second portion is a cylindrical member arranged concentrically with the rotation axis; a transmission member that is spirally wound around the outer circumferential surface of the cylindrical member in a winding region that exceeds one circumference of the outer circumferential surface, and that includes an upper end portion and a lower end portion that are fixed to the cylindrical member; The other of the first portion and the second portion is a drive unit that applies a driving force to the transmission member to feed the transmission member, a rotation mechanism, wherein at least one guide member is provided on the outer peripheral surface of the cylindrical member, the guide member being positioned outside the winding area on an extension of at least one of the upper end and the lower end in the circumferential direction and adjacent to the winding area in the direction of the rotation axis.

2. the at least one guide member includes a lower guide member that is disposed at a position outside the winding region on an extension of the lower end portion in the circumferential direction, The rotation mechanism according to claim 1 , wherein the lower guide member includes an upwardly inclined surface that guides a portion of the transmission member near the upper end portion upward.

3. the at least one guide member includes an upper guide member disposed at a position outside the winding region on an extension of the upper end portion in the circumferential direction, The rotation mechanism according to claim 1 or 2, wherein the upper guide member includes a downwardly inclined surface that guides downward a portion of the transmission member near the lower end portion.

4. The rotation mechanism according to claim 1 , wherein the at least one guide member is disposed adjacent to at least one of the upper end portion and the lower end portion in the circumferential direction.

5. a traveling carriage including the first portion; a main body having the second portion and a transfer device attached below the second portion to transfer an object to be transported; The overhead transport vehicle, wherein the rotation mechanism according to claim 1 causes the main body to rotate about the rotation axis relative to the traveling carriage.

Images