Overhead transport vehicle

Abstract

An overhead transport vehicle is provided with: a traveling trolley that travels on a track; a main body provided so as to be rotatable with respect to the traveling carriage; the transferring device is arranged on the main body part and can send out the articles in the horizontal direction; and an obstacle sensor provided in the main body so as not to coincide with the direction in which the transfer device delivers the article, the obstacle sensor detecting an obstacle located in front of the traveling direction of the traveling trolley.

Description

Technical Field

[0001] One aspect of the present invention relates to an overhead transport vehicle. Background Art

[0002] There is known an overhead transport vehicle, which includes a traveling trolley that travels along a track, and a main body connected to the traveling trolley and arranged below the track. This overhead transport vehicle is provided with an obstacle sensor to detect obstacles that become obstacles during travel. For example, the overhead transport vehicle described in Patent Document 1 is provided with a transfer device that is connected to the bottom of the traveling trolley and can rotate relative to the traveling trolley. The obstacle sensor is mounted on the lower end of a support member extending downward from the traveling trolley, and the support member is arranged at a portion around the transfer device.

[0003] Prior Art Literature

[0004] [Patent Document 1] Japanese Patent No. 7040637 Summary of the invention

[0005] Problem that the invention aims to solve

[0006] However, the above-mentioned known overhead transport vehicle is provided with a supporting structure around a portion of the transfer device. Therefore, even if the transfer device is arranged to be rotatable relative to the traveling trolley, the items cannot be sent in the direction where the supporting structure is arranged (horizontal movement), and the transfer position that can be transferred is limited.

[0007] In this regard, an object of one aspect of the present invention is to provide an overhead travelling truck that can increase the degree of freedom of a transfer device in transferring an article.

[0008] Technical solutions to the problem

[0009] An overhead transport vehicle according to one aspect of the present invention comprises: a traveling trolley that travels on a track; a main body that is configured to be able to rotate relative to the traveling trolley; a transfer device that is provided in the main body and is configured to be able to deliver articles in a horizontal direction; and an obstacle sensor that is provided in the main body in a manner that does not overlap with the direction in which the transfer device delivers articles, so as to detect obstacles located in front of the traveling direction of the traveling trolley.

[0010] In the overhead transport vehicle of this structure, when the main body rotates relative to the traveling carriage, the obstacle sensor rotates integrally with the transfer device, and the position of the obstacle sensor does not coincide with the direction in which the transfer device delivers the article. Therefore, in the direction in which the article is delivered from the transfer device, a support member for mounting the obstacle sensor on the traveling carriage is not required. As a result, the transfer device can deliver the article in any direction, thereby increasing the degree of freedom of the transfer device in transferring the article.

[0011] In an overhead transport vehicle according to one aspect of the present invention, in a track in which a plurality of first rails extending in a first direction and a plurality of second rails extending in a second direction are arranged in a grid shape, the traveling vehicle can move in the first direction by traveling on a pair of first rails adjacent to the second direction, and can move in the second direction by traveling on a pair of second rails adjacent to the first direction, the second direction being a direction orthogonal to the first direction. In this configuration, the degree of freedom of the traveling direction of the traveling vehicle can be increased, and the degree of freedom of the transfer device for the transfer position of the article can be increased.

[0012] In one aspect of the present invention, the overhead travelling vehicle may further include: a control unit that rotates the main body so that the detection area of ​​the obstacle sensor faces forward in the travelling direction of the travelling vehicle when the travelling vehicle starts travelling. In this configuration, regardless of where the obstacle sensor is disposed on the main body, an obstacle located forward in the travelling direction can be detected when the overhead travelling vehicle is travelling.

[0013] The obstacle sensor of an overhead travelling vehicle according to one aspect of the present invention is configured to include a first sensor and a second sensor, the first sensor being configured to detect an obstacle located on one side of a predetermined direction of a main body, and the second sensor being configured to detect an obstacle located on the other side of the predetermined direction, and the control unit being able to rotate the main body in a manner such that the detection area of ​​one of the first sensor and the second sensor faces forward in the direction of travel of the travelling vehicle according to the direction of travel when the travelling vehicle starts to travel, and making it impossible for the other of the first sensor and the second sensor to detect obstacles. In the present configuration in which two obstacle sensors are provided on the main body, the time required to rotate the main body in a manner such that the detection area of ​​the obstacle sensor faces forward in the direction of travel of the travelling vehicle can be shortened compared to a case in which only one obstacle sensor is provided on the main body.

[0014] In an overhead transport vehicle according to one aspect of the present invention, the control unit can determine which detection area of ​​the first sensor and the second sensor is to be directed forward in the travel direction of the travel vehicle based on information about which direction orthogonal to the travel direction the article will be transferred in the next transfer location. In this configuration, the time required for the turn for transfer after reaching the next transfer location can be shortened.

[0015] Effect of the Invention: According to one aspect of the present invention, the degree of freedom of the transfer position of an article by a transfer device can be increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a perspective view showing an example of a transport vehicle system according to the embodiment.

[0017] Figure 2 Yes means Figure 1An exploded perspective view of the four track units that make up the track assembly and the connecting members that connect them.

[0018] Figure 3 Observed from the X direction Figure 1 Side view of the medium-height transport vehicle.

[0019] Figure 4 Observed from above Figure 1 A three-dimensional view of a medium-height transport vehicle.

[0020] Figure 5 This is a perspective view showing only the rail portion of the rail assembly.

[0021] Figure 6 It is a cross-sectional view showing a connection portion between a plurality of rail units.

[0022] Figure 7 Observed from below Figure 1 A three-dimensional view of a medium-height transport vehicle.

[0023] Figure 8 Observed from the Y direction Figure 1 Side view of the medium-height transport vehicle.

[0024] Fig. 9 It is a block diagram showing the functional configuration of the overhead travelling vehicle system according to the embodiment.

[0025] Description of Reference Numerals

[0026] 1: Overhead transport vehicle system; 2: Overhead transport vehicle (transport vehicle); 5: System controller; 8: Trolley controller (control unit); 10: Main body; 18: Transfer device; 20: Traveling trolley; 30: Traveling unit; 50: Trolley unit; 61: Obstacle sensor; 61a: 1st sensor; 61b: 2nd sensor; 70: Article pressing mechanism; 71: Anti-shaking component; 72: Article falling prevention component; 73: Cover falling prevention component; M: Article; R: Track; R1: 1st track; R2: 2nd track; R3: Intersection track. DETAILED DESCRIPTION

[0027] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Furthermore, in the description of the accompanying drawings, the same elements are marked with the same symbols and repeated descriptions are omitted. In the accompanying drawings, for the convenience of description, the various components of the embodiments have been appropriately changed in scale to express them. In some of the accompanying drawings, an XYZ orthogonal coordinate system is also recorded. In the following description, this coordinate system is referred to for the convenience of description. Hereinafter, a direction along the horizontal plane is set as the X direction (the first direction), a direction orthogonal to the X direction and along the horizontal plane is set as the Y direction (the second direction), and a vertical direction is set as the Z direction for description.

[0028] like Figure 1 As shown, the overhead conveyor system 1 of the embodiment of the present invention is a grid system (conveyor system or rail trolley system) for conveying articles M through overhead conveyor vehicles 2, for example, in a clean room of a semiconductor manufacturing plant. The overhead conveyor system 1, for example, has a plurality of overhead conveyor vehicles 2 (hereinafter collectively referred to as "conveyor vehicles 2"), a system controller 5 for controlling the plurality of conveyor vehicles 2, and a track R for the plurality of conveyor vehicles 2 to travel. The conveyor vehicle 2 moves along the track R of the overhead conveyor system 1. The conveyor vehicle 2 travels along the track R to convey articles M such as a front opening wafer box (FOUP, Front Opening Unified Pod) for accommodating semiconductor wafers, or a reticle box (reticle pod) for accommodating a reticle. The conveyor vehicle 2 may also be referred to as a trolley, a conveyor vehicle, a conveying trolley, or a traveling trolley, etc. Through a plurality of conveyor vehicles 2, high-density conveyance of articles M can be achieved, thereby improving the conveyance efficiency of articles M. Furthermore, the overhead conveyor system 1 may also only have one conveyor vehicle 2.

[0029] The track R is provided on the ceiling or near the ceiling of a building such as a clean room. The track R is provided adjacent to, for example, a processing device, a storage (automatic warehouse), etc. The processing device is, for example, an exposure device, a coating and developing device, a film forming device, an etching device, etc., which performs various processes on the semiconductor wafers in the article M transported by the transport vehicle 2. The storage stores the article M transported by the transport vehicle 2.

[0030] The rails R are arranged in a grid pattern when viewed from above (see also Figure 5 ). The track R extends in the horizontal direction. In the present embodiment, the track R is constructed by arranging a plurality of track units 100 including a first track R1, a second track R2, and an intersection track R3 in the X direction and the Y direction. The overhead transport vehicle system 1 comprises: a plurality of track units 100 arranged in the X direction and the Y direction; and a plurality of connecting members 140 for connecting the plurality of track units 100 to each other. A track assembly 200 is formed by a plurality of track units 100 and a plurality of connecting members 140. In the portion where the track units 100 are connected to each other by the connecting members 140, the track assembly 200 is suspended by a plurality of hanging members H from a ceiling, etc., not shown in the figure.

[0031] Figure 2 It means composition Figure 1An exploded three-dimensional view of the four track units 100 of the middle track assembly 200 and the connecting member 140 connecting them. Each track unit 100 is a rectangular parallelepiped (frame-shaped) component having the same structure. Each track unit 100 includes: two first track components 110 arranged along the X direction; two second track components 120 arranged along the Y direction; and four cross track components 130 arranged in a manner to form gaps on the extension lines of the first track components 110 and the second track components 120 (i.e., the intersection positions of the grid). When the track unit 100 is viewed from above, the two parallel first track components 110 and the two parallel second track components 120 are arranged in a square shape, and the four cross track components 130 are arranged at the vertices of the square.

[0032] Each track unit 100 is made of metal, for example, and is an integrated unit after the first track member 110, the second track member 120, and the cross track member 130 are formed. Each first track member 110 includes: a first beam 111, which is arranged at the upper end of the track unit 100 and extends in the X direction; a first rail (travel rail) R1, which is arranged at the lower end of the track unit 100 and extends in the X direction; and a first support wall 113, which is arranged between the first beam 111 and the first rail R1, and is connected to the first beam 111 and the first rail R1. Each second track member 120 includes: a second beam portion 121, which is arranged at the upper end of the track unit 100 and extends in the Y direction; a second track (travel track) R2, which is arranged at the lower end of the track unit 100 and extends in the Y direction; and a second support wall 123, which is arranged between the second beam portion 121 and the second track R2, and is connected to the second beam portion 121 and the second track R2. A lattice-shaped structure extending along the XY plane is formed at the upper end of the track assembly 200 by a plurality of first beam portions 111 and a plurality of second beam portions 121. The first support wall 113 extends along the XZ plane. The second support wall 123 extends along the YZ plane.

[0033] The intersection rail member 130 includes: an intersection support column 133 extending along the Z direction (vertical direction) at a 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 column 133 .

[0034] like Figure 1 and Figure 5As shown, a plurality of first rails R1 extend in the X direction respectively. A plurality of second rails R2 extend in the Y direction respectively. The rail R is formed into a lattice shape by a plurality of first rails R1 and a plurality of second rails R2 in a plan view. The rail R is a plurality of squares formed by a plurality of first rails R1 and a plurality of second rails R2. The intersection rail R3 is arranged in the following part: corresponding to the intersection of the first rail R1 and the second rail R2. The intersection rail R3 is adjacent to the first rail R1 at a distance in the X direction. The intersection rail R3 is adjacent to the second rail R2 at a distance in the Y direction. The intersection rail R3 can be used in any of the following situations: when the transport vehicle 2 travels along the first rail R1, when the transport vehicle 2 travels along the second rail R2, and when the transport vehicle 2 travels from the first rail R1 to the second rail R2 or from the second rail R2 to the first rail R1.

[0035] Each track unit 100 is formed with a square (or rectangular) track R corresponding to one grid on the inside. A plurality of track units 100 are arranged in the X direction and the Y direction, and a plurality of first tracks R1 are connected and extended in the X direction, and a plurality of second tracks R2 are connected and extended in the Y direction. On the X direction line, two intersection tracks R3 are arranged at intervals between one first track R1 and another first track R1. On the Y direction line, two intersection tracks R3 are arranged at intervals between one second track R2 and another second track R2. The track R is described below from another perspective. When focusing on the four squares formed by two squares arranged in the X direction and two squares arranged in the Y direction, four intersecting rails R3 adjacent in the X direction and the Y direction are arranged at intervals (with respect to the first rails R1) between the two first rails R1 adjacent in the Y direction and the other two first rails R1 adjacent in the Y direction. In addition, the same four intersecting rails R3 as described above are arranged at intervals (with respect to the second rails R2) between the two second rails R2 adjacent in the X direction and the other two second rails R2 adjacent in the X direction.

[0036] In the track assembly 200, a plurality of first tracks R1, a plurality of second tracks R2, and a plurality of intersection tracks R3 are arranged to be spaced apart from each other by a predetermined interval, thereby constructing the track R. Between each first track R1 and each intersection track R3, a gap G corresponding to the above interval is formed. Between each second track R2 and each intersection track R3, a gap G corresponding to the above interval is formed. The gap G in the track R has a fixed size. Each first track R1 includes a first running surface R1a having a flat and horizontal upper surface, and the running wheels 31 of the transport vehicle 2 run along the X direction (first running direction D1) on the first running surface R1a. Each second track R2 includes a second running surface R2a having a flat and horizontal upper surface, and the running wheels 31 of the transport vehicle 2 run along the Y direction (second running direction D2) on the second running surface R2a. The intersection track R3 includes an intersection running surface R3a having a flat and horizontal upper surface. The first running surface R1a, the second running surface R2a, and the intersecting running surface R3a have the same height throughout the entire track R. The first running surface R1a, the second running surface R2a, and the intersecting running surface R3a are arranged on the same or substantially the same horizontal plane.

[0037] For example, a gap as large as the gap G is not formed between the four intersection rails R3. When the transport vehicle 2 passes through a plurality of rail units 100 in a straight line, the running wheels 31 of the transport vehicle 2 travel on the intersection running surface R3a. At this time, the running wheels 31 pass over any two of the four intersection rails R3. Alternatively, when the transport vehicle 2 changes its running direction between the rail units 100 (changes its running direction by 90 degrees, i.e., turns), the running wheels 31 of the transport vehicle 2 pass over the intersection running surface R3a (changes direction).

[0038] As described above, in the track assembly 200, the first track member 110, the second track member 120, and the cross track member 130 constitute the grid-shaped track R. The layout of the grid-shaped track R in the overhead travelling vehicle system 1 can be appropriately adjusted or changed by arranging the plurality of track units 100 (including adding or deleting the track units 100).

[0039] Reference Figure 2 and Figure 6 , the connection structure of the track unit 100 formed by the connection member 140 is described. Figure 2 and Figure 6As shown, each connecting member 140 includes an upper connecting member 141 and a lower connecting member 142. The upper surface of any one of the four corners of a plurality of (typically 4) rail units 100 is mounted on the upper connecting member 141 which is in the shape of a plate or a frame extending horizontally. The upper connecting member 141 abuts against the vicinity of the intersection of the first beam portion 111 and the second beam portion 121 in each rail unit 100. The lower connecting member 142 which is in the shape of a plate or a frame extending horizontally supports the lower surface of any one of the four corners of a plurality of (typically 4) rail units 100. The lower connecting member 142 abuts against the intersection rail R3 in each rail unit 100.

[0040] The rod-shaped hanging member H extending in the vertical direction passes through 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 track unit 100 by means of a fastening member (not shown), thereby connecting the track units 100 to each other. Furthermore, a space 100e extending in the Z direction is formed between the track units 100, and a space R3e extending in the Z direction is formed between the four intersecting rails R3 adjacent in the X direction and the Y direction (the central part when viewed from above). The hanging member H is inserted through the space 100e and the space R3e, and the upper connecting member 141 and / or the lower connecting member 142 are fixed to the hanging member H.

[0041] The overhead travelling vehicle system 1 includes a communication system (not shown). The communication system is used for communication between the travelling vehicle 2 and the system controller 5. The travelling vehicle 2 and the system controller 5 are connected to each other so as to be able to communicate via the communication system.

[0042] Then, refer to Figure 1 , Figure 3 and Figure 4 , the structure of the transport vehicle 2 is described. Figure 1 and Figure 3 As shown, the transport vehicle 2 is configured to be able to travel along the track R. The transport vehicle 2 has: a traveling trolley 20, which travels on the track R; and a main body 10, which is installed at the lower part of the traveling trolley 20 and can freely rotate relative to the traveling trolley 20. The traveling trolley 20 includes: a trolley unit 50, for example, in a rectangular shape, which is arranged below the track R; a traveling part 30, which is arranged at the four corners of the trolley unit 50 when viewed from above, and protrudes upward from the trolley unit 50; and four wheel rotation mechanisms 40, which make the four traveling wheels 31 in the traveling part 30 rotate relative to the trolley unit 50. A trolley controller (control unit) 8 is provided inside the trolley unit 50.

[0043] The main body 10 is disposed below the track R. Figure 3 and Figure 4As shown in FIG. 1 , the main body 10 has a main frame 12 formed, for example, in a cylindrical shape. The main frame 12 includes a disc-shaped top plate 12a and a cylindrical frame 12b hanging down from the peripheral edge of the top plate 12a, and has a shape with an open lower surface. The main body 10 is formed to converge into one square in the track R when viewed from above (see FIG. 1 ). Figure 1 ) size. The transport vehicle 2 can pass by alternately with another transport vehicle 2 running on the adjacent first track R1 or second track R2. The main body 10 has a transfer device 18 arranged inside the main frame 12. The transfer device 18 is, for example, rectangular in a plan view. The cylindrical frame 12b is open at a portion of the circumferential direction. The range formed by the open portion (notch) is large enough to allow the transfer device 18 to pass through. When the transfer device 18 moves horizontally, it passes through the open portion of the cylindrical frame 12b.

[0044] The main body 10 is mounted on the lower part of the trolley unit 50 and can freely rotate around the rotation axis L10 in the Z direction relative to the trolley unit 50. The traveling wheels 31 arranged at the four corners of the trolley unit 50 are placed on the track R (on the first traveling surface R1a, the second traveling surface R2a, or the intersection traveling surface R3a). The trolley unit 50 is suspended from the track R via four traveling wheels 31 and four wheel rotation mechanisms 40. The trolley unit 50 and the main body 10 can be stably suspended by the four traveling wheels 31, and the main body 10 can be stably driven. That is, the transport vehicle 2 is suspended and supported on the traveling wheels 31 that travel along the track R, and moves below the track R.

[0045] The transfer device 18 moves in the horizontal direction relative to the main body 10 to transfer the article M between the load port (loading platform). The transfer device 18 is disposed below the top plate 12a of the main frame 12. The main body 10 including the transfer device 18 can rotate around the rotation axis L10 by a rotation drive unit such as an electric motor (not shown) disposed on the top plate 12a. The transfer device 18 includes: an article holding portion 13 that holds the article M on the lower side of the track R; a lifting drive portion 14 that lifts the article holding portion 13 in the vertical direction; and a sliding mechanism 11 that slides the lifting drive portion 14 in the horizontal direction. The sliding mechanism 11 is retained on the lower surface of the top plate 12a. A first rotation drive portion 16 is provided between the sliding mechanism 11 and the lifting drive portion 14, and the first rotation drive portion 16 drives the lifting drive portion 14 to rotate relative to the sliding mechanism 11 around the rotation axis L14. The first rotation drive unit 16 is provided below the slide mechanism 11, and the lifting drive unit 14 is provided below the first rotation drive unit 16. The article holding unit 13 is provided below the lifting drive unit 14 via a plurality of hanging members 13b. The load port is a transfer destination or a transfer departure point of the transport vehicle 2, and is a place where the article M is transferred to and from the transport vehicle 2.

[0046] The article holding part 13 holds the article M in a hanging manner by gripping the flange Ma of the article M. The article holding part 13 is, for example, a clamp, and has a claw 13a that can move in the horizontal direction. The article holding part 13 holds the article M by making the claw 13a enter under the flange Ma of the article M and by raising the article holding part 13. The article holding part 13 is connected to a hanging member 13b such as a wire or a belt.

[0047] The lifting drive unit 14 is, for example, a hoist, which lowers the article holding unit 13 by unwinding the hanging member 13b, and raises the article holding unit 13 by winding up the hanging member 13b. The lifting drive unit 14 is controlled by the carriage controller 8 and can lower or raise the article holding unit 13 at a predetermined speed. In addition, the lifting drive unit 14 is controlled by the carriage controller 8 and can maintain the article holding unit 13 at a target height.

[0048] The sliding mechanism 11 has a plurality of movable plates arranged to overlap in the Z direction, for example. By rotating the main body 10, the sliding mechanism 11 moves the first rotation drive unit 16, the lifting drive unit 14, and the article holding unit 13 installed on the bottom movable plate to any direction in the horizontal plane. The moving direction of the movable plate in the sliding mechanism 11 is determined by the rotation angle of the main body 10 relative to the trolley unit 50. In the main body 10, the orientation of the transfer device 18 and the main frame 12 is set so that the moving direction of the movable plate coincides with the position of the open part of the cylindrical frame 12b.

[0049] The first rotation drive unit 16 includes, for example, an electric motor, etc., which rotates the lifting drive unit 14 (and the article holding unit 13) around a rotation axis L14 extending in the vertical direction within a specified angle range. The angle that can be rotated by the first rotation drive unit 16 is, for example, any angle below 180 degrees, but the upper limit is not limited to 180 degrees. The first rotation drive unit 16 can make the laterally extended article holding unit 13 (or the article M held by the article holding unit 13) face the desired direction. The sliding mechanism 11 and the first rotation drive unit 16 are controlled by the trolley controller 8. Furthermore, even in the state where the movable plate of the sliding mechanism 11 is not moved but stored ( Figure 3 In the state shown by the solid line in FIG. 1 , the lifting drive unit 14 can also be rotated by the first rotation drive unit 16. In this case, for example, the rotation axis L14 of the lifting drive unit 14 coincides with the rotation axis L10 of the main body 10.

[0050] The trolley unit 50 has a cylindrical support member (cylindrical member) 52 at the lower end. On the lower surface side of the support member 52, the top plate portion 12a of the main frame 12 is rotatably mounted. For example, a second rotation drive unit 52A such as an electric motor is provided on the top plate portion 12a. The driving force of the second rotation drive unit 52A is transmitted to the support member 52, and the main frame 12 rotates relative to the trolley unit 50 around the rotation axis L10 extending in the vertical direction. The main frame 12 can rotate at any angle of, for example, 360 degrees or more and 540 degrees or less, but the upper limit is not limited to 540 degrees and the lower limit is not limited to 360 degrees. The sliding mechanism 11 is mounted on the lower surface side of the top plate portion 12a, and the top plate portion 12a supports the sliding mechanism 11. The main frame 12 and the transfer device 18 are integrated, and the main frame 12 rotates together with the transfer device 18. The transport vehicle 2 can transfer the article M relative to the load port by using the transfer device 18.

[0051] A cover 17 is attached to the outer surface of the cylindrical frame 12b. The cover 17 surrounds the transfer device 18 and the article M held by the transfer device 18. The cover 17 is a cylindrical shape with an open lower end, and has a shape in which a portion (the open portion) of the movable plate of the slide mechanism 11 protrudes is cut out.

[0052] like Figure 7 and Figure 8 As shown, an obstacle sensor 61 is provided on the cylindrical frame 12b, and the obstacle sensor 61 detects obstacles in front of the travel direction of the transport vehicle 2 (traveling trolley 20). In more detail, the obstacle sensor 61 is provided at the lower part of the cylindrical frame 12b in a manner protruding downward from the lower end of the cylindrical frame 12b (hood 17). The obstacle sensor 61 is, for example, an optical sensor that detects obstacles by emitting detection light. The emission area of ​​the detection light can be linear, strip-shaped, or radial. In addition, the obstacle sensor 61 can also be a sensor that can detect the distance from the obstacle sensor 61. The detection result of the obstacle sensor 61 is obtained by the trolley controller 8. Furthermore, the obstacle sensor 61 can also be arranged at the lower part of the cylindrical frame 12b without protruding downward from the lower end of the cylindrical frame 12b, but by cutting a part of the lower part of the hood 17.

[0053] The obstacle sensor 61 of the present embodiment is configured to include a first sensor 61a and a second sensor 61b, wherein the first sensor 61a is configured to detect an obstacle located on one side of a predetermined direction D in the main body 10, and the second sensor 61b is configured to detect an obstacle located on the other side of the predetermined direction D. For example, when the travel vehicle 20 is turned so that the predetermined direction D of the main body 10 coincides with the X direction, the first sensor 61a detects an obstacle located on one side of the X direction, and the second sensor 61b detects an obstacle located on the other side of the X direction. Furthermore, as described in detail in the following paragraph, when the transport vehicle 2 is traveling, the detection function of one of the first sensor 61a and the second sensor 61b is invalidated. Furthermore, the predetermined direction D of the main body 10 indicates the orientation of the main body 10. The orientation of the main body 10 can be set based on, for example, a direction along the arrangement direction of the pair of claws 13a / 13a, a direction along the arrangement direction of the pair of anti-sway members 71 / 71, a direction orthogonal to the protruding direction of the movable plate of the sliding mechanism 11, etc.

[0054] like Figure 8 As shown, the detection direction of the obstacle sensor 61 (the emission direction of the detection light) is slightly downward from the horizontal direction. As a result, the obstacle sensor 61 will not detect other transport vehicles 2, but can detect obstacles that will enter the driving area of ​​the transport vehicle 2 from the vertical direction below, or obstacles that are entering the driving area of ​​the transport vehicle 2 from below. Furthermore, the obstacles mentioned here include certain components, a part of the operator, etc.

[0055] Hereinafter, as an article M, a case where a container (FOUP, etc.) having a cover on the front surface is transported is cited as an example for explanation. In this case, the article M has, in addition to the flange portion Ma, a front surface Mb having a cover, a side surface Mc that is a side surface other than the front surface Mb, a bottom surface Md that is a bottom, and an upper surface Me having the flange portion Ma. A positioning hole is provided on the bottom surface Md, and the positioning hole engages with a positioning pin provided on the load port when the article M is placed on the load port. For such an article M, the orientation of the article is set according to the arrangement direction of the cover, the arrangement direction (arrangement pattern) of the positioning hole, etc. as described above.

[0056] The main body 10 includes an article pressing mechanism 70 , which is configured to include a pair of shaking prevention members 71 / 71 , a pair of article drop prevention members 72 / 72 , and a pair of cover drop prevention members 73 / 73 .

[0057] The purpose of providing a pair of anti-swaying members 71 / 71 is to contact the article M and prevent the article M from shaking during driving. One of the pair of anti-swaying members 71 / 71 is provided at the first end 12c in the specified direction D of the main body 10, and the other of the pair of anti-swaying members 71 / 71 is provided at the second end 12d. The pair of anti-swaying members 71 / 71 are each provided to enter or retreat from a specified position, to contact the article M at the entry position, and to leave the article M at the retreat position.

[0058] Each of the pair of anti-sway members 71 / 71 is composed of two roller members arranged in a direction orthogonal to the specified direction D (in the present embodiment, the Y direction). Thus, when the pair of anti-sway members 71 / 71 enter the entry position and contact the article M, the friction between the pair of anti-sway members 71 / 71 and the article M can be reduced. As described above, for example, when the pair of anti-sway members 71 / 71 rotates relative to the traveling carriage 20 so that the specified direction D of the main body 10 coincides with the X direction, the pair of anti-sway members 71 / 71 contact the article M in a manner of clamping the article M from both ends in the X direction.

[0059] The purpose of providing a pair of article-dropping prevention members 72 / 72 is to prevent the article M from falling downward from the transfer device 18 during travel. One of the pair of article-dropping prevention members 72 / 72 is provided at the first end 12c in the predetermined direction D of the main body 10, and the other of the pair of article-dropping prevention members 72 / 72 is provided at the second end 12d. The pair of article-dropping prevention members 72 / 72 are each provided to enter a predetermined position or retreat from a predetermined position, and are located below the article M at the entered position and away from the article M at the retreated position.

[0060] The purpose of providing a pair of cover-drop prevention members 73 / 73 is to prevent the cover provided on the front surface Mb from falling down to the bottom of the transport vehicle 2 when it falls off. One of the pair of cover-drop prevention members 73 / 73 is provided at the first end 12c in the prescribed direction D of the main body 10, and the other of the pair of cover-drop prevention members 73 / 73 is provided at the second end 12d. The pair of cover-drop prevention members 73 / 73 are each provided to enter a prescribed position or retreat from a prescribed position, and are located in front of the cover of the article M at the entered position, and are away from the cover of the article M at the retreated position.

[0061] The pair of anti-sway members 71 / 71, the pair of anti-article drop members 72 / 72, and the pair of anti-cover drop members 73 / 73 are driven to enter the entry position and retreat to the retreat position by a driving unit such as an electric motor not shown. That is, the pair of anti-sway members 71 / 71, the pair of anti-article drop members 72 / 72, and the pair of anti-cover drop members 73 / 73 enter the entry position at approximately the same time and retreat to the retreat position at approximately the same time. The pair of anti-sway members 71 / 71, the pair of anti-article drop members 72 / 72, and the pair of anti-cover drop members 73 / 73 are connected to the driving unit via a connecting rod member or the like.

[0062] The travel unit 30 has four travel wheels 31. Two auxiliary wheels 32 are provided on each of the travel wheels 31. Figure 4 As shown, the traveling wheels 31 are arranged to protrude upward from the upper surface cover 51 at the positions of the four corners of the trolley unit 50. Each traveling wheel 31 can rotate around a horizontal or substantially horizontal axle along the XY plane. A traveling drive motor 33 is provided on the rotating shaft 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 rotation and reverse rotation, for example. The traveling wheels 31 each roll on the track R. The traveling wheels 31 each roll on the traveling surfaces R1a, R2a, and R3a of the first track R1, the second track R2, and the intersection track R3 to drive the transport vehicle 2. Furthermore, it is not limited to that all four traveling wheels 31 are driven to rotate by the driving force of the traveling drive motor 33, and it can also be a configuration that drives some of the four traveling wheels 31 to rotate.

[0063] Four wheel turning mechanisms 40 are fixed to a frame (not shown) in the carriage unit 50, and a pedestal 34 is connected to each wheel turning mechanism 40 via a turning axis of the wheel turning mechanism 40. On the pedestal 34, a traveling wheel 31, two auxiliary wheels 32, and a traveling drive motor 33 are mounted via a connecting portion 35 and a supporting member 36. For example, a square upper surface cover 51 is provided on the upper surface of the housing 53, and the pedestal 34 is arranged at the notches formed at the four corners of the upper surface cover 51. The connecting portion 35, the traveling wheel 31, the auxiliary wheel 32, and the traveling drive motor 33 are arranged at a position higher than the upper surface cover 51.

[0064] like Figure 3 and Figure 4As shown, the connecting portion 35 connects the trolley unit 50 (more specifically, the wheel turning mechanism 40 fixed in the trolley unit 50) and the traveling wheel 31. Through this connection structure, the trolley unit 50 and the main body 10 are arranged at a position lower than the track R, and are in a state of being suspended from the traveling portion 30. The connecting portion 35 is formed to have a thickness that can pass through the gap G between the first track R1 and the intersection track R3, and between the second track R2 and the intersection track R3. The support member 36 is provided on the upper part of the connecting portion 35, and rotatably supports the rotating shaft of the traveling wheel 31 and the rotating shaft of the auxiliary wheel 32. The support member 36 maintains the relative position of the traveling wheel 31 and the auxiliary wheel 32.

[0065] like Figure 4 As shown, the traveling wheel 31 is arranged to be able to rotate around a rotation axis L30 extending in the vertical direction. The four rotation axes L30 are arranged at the vertex positions of a square when viewed from above, and the rotation axis L10 is arranged at the center of the rotation axis L30. In other words, the four rotation axes L30 are arranged at positions that are four-fold symmetrical relative to the rotation axis L10 of the main body 10. When viewed from above, the position of the traveling wheel 31 is different from (offset from) the position of the rotation axis L30. The traveling wheel 31 rotates through the wheel rotation mechanism 40, and as a result, the driving direction of the transport vehicle 2 can be changed.

[0066] One auxiliary wheel 32 is disposed in front of and behind the traveling direction of the traveling wheel 31. Each of the auxiliary wheels 32 can rotate around a horizontal or substantially horizontal axle along the XY plane. The lower end of the auxiliary wheel 32 is set, for example, to be higher than the lower end of the traveling wheel 31. Therefore, when the traveling wheel 31 travels on the traveling surface R1a, R2a, R3a, the auxiliary wheel 32 does not contact the traveling surface R1a, R2a, R3a. In addition, when the traveling wheel 31 passes 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 auxiliary wheel 32 contacts the auxiliary member (details will be described later) provided on the first rail R1 and the second rail R2, thereby suppressing the falling of the traveling wheel 31. Furthermore, it is not limited to providing two auxiliary wheels 32 on one traveling wheel 31, and for example, one auxiliary wheel 32 may be provided on one traveling wheel 31.

[0067] The four wheel turning mechanisms 40 are, for example, arranged at the positions of the four corners in the housing 53 of the trolley unit 50. Each wheel turning mechanism 40 has a steering motor 43 and a driving force transmission part 42 arranged between the steering motor 43 and the traveling wheel 31. The driving force transmission part 42 is fixed to a frame (not shown) in the trolley unit 50. The driving force transmission part 42 is connected to the pedestal part 34 via a swing axis. Each wheel turning mechanism 40 makes the pedestal part 34, the connecting part 35, the supporting member 36, the traveling wheel 31, the auxiliary wheel 32, and the traveling drive motor 33 rotate integrally around the swing axis L30. When the transport vehicle 2 is located at the center of each track unit 100, each traveling wheel 31 is rotated 90 degrees around each swing axis L30 as the center. Thus, the traveling wheel 31 rotates on the intersection track R3. Thus, the transport vehicle 2 can turn. The so-called turning means that the transport vehicle 2 switches from the first state of traveling in the first driving direction D1 to the second state of traveling in the second driving direction D2, or the transport vehicle 2 switches from the second state of traveling in the second driving direction D2 to the first state of traveling in the first driving direction D1. The turning of the transport vehicle 2 is performed, for example, when the transport vehicle 2 is stopped. The turning of the transport vehicle 2 can also be performed when the transport vehicle 2 is stopped but the article M is moving (for example, rotating). The drive of the wheel rotating mechanism 40 is controlled by the trolley controller 8.

[0068] As described above, a gap G is formed on the rail R. When the transport vehicle 2 travels on the first rail R1 and crosses the second rail R2, or when the transport vehicle 2 travels on the second rail R2 and crosses the first rail R1, a portion of the transport vehicle 2 (specifically, for example, the connection portion 35) passes through the gap G.

[0069] Furthermore, guide rollers that abut against the side of the intersection rail R3 may be provided between the travel wheel 31 and the wheel turning mechanism 40 (for example, near the connection portion 35). The guide rollers can prevent the travel vehicle 20 (transport vehicle 2) from being displaced relative to the rail R.

[0070] The transport vehicle 2 includes a position detection unit (not shown) for detecting position information. The position detection unit detects the current position of the transport vehicle 2 by detecting, for example, a position mark indicating position information provided on the rail R. The position detection unit detects the position mark in a non-contact manner.

[0071] Figure 3 and Fig. 9The trolley controller 8 shown centrally controls the transport vehicle 2. The trolley controller 8 is a computer including a central processing unit (CPU), a read-only memory (ROM), and a random access memory (RAM). The trolley controller 8 can be configured as software that loads a program stored in the ROM onto the RAM and is executed by the CPU. The trolley controller 8 can also be configured as hardware formed by electronic circuits, etc. The trolley controller 8 can be composed of one device or a plurality of devices. When composed of a plurality of devices, a trolley controller 8 is logically constructed by connecting them via a communication network such as the Internet or an intranet. The trolley controller 8 can be provided in the trolley unit 50, for example.

[0072] The trolley controller 8 controls the travel of the transport vehicle 2 according to the transport instruction. The trolley controller 8 controls the travel of the transport vehicle 2 by controlling the travel drive motor 33 and the steering motor 43, etc. The trolley controller 8 controls, for example, the travel speed, the action related to stopping, and the action related to the direction change. The trolley controller 8 controls the transfer action of the transport vehicle 2 according to the transport instruction. The trolley controller 8 controls the transfer direction of the transfer device 18 by controlling the rotation (rotation) of the main body 10 (main body frame 12 and transfer device 18). The trolley controller 8 controls the transfer action of the transport vehicle 2 by controlling the transfer device 18, etc. The trolley controller 8 controls the grasping action of grasping the article M arranged at the specified load port, and the unloading action of unloading the held article M to the specified load port.

[0073] The trolley controller 8 controls the travel drive motor 33 (travel unit 30) based on the detection result of the first sensor 61a or the second sensor 61b. For example, when the first sensor 61a or the second sensor 61b detects an obstacle, the trolley controller 8 controls the travel drive motor 33 to stop the travel of the travel trolley 20. When the first sensor 61a and the second sensor 61b are sensors that can detect the distance to the obstacle, the travel drive motor 33 can be controlled to make the travel trolley 20 travel slowly when an obstacle is detected within the first distance, and the travel drive motor 33 can be controlled to stop the travel trolley 20 when an obstacle is detected within the second distance shorter than the first distance.

[0074] When the traveling trolley 20 starts to travel, the trolley controller 8 drives the second rotary drive unit 52A to rotate the main body 10, and the orientation of the article M held by the transfer device 18 is fixed relative to the traveling direction of the traveling trolley 20. As described above, the article M has an orientation (directivity), and the trolley controller 8 rotates the main body 10 so that the front surface Mb provided with the cover faces a direction orthogonal to the traveling direction. The direction orthogonal to the traveling direction here may be the left or the right when the traveling trolley 20 is viewed from the front in the traveling direction.

[0075] like Figure 7 and Figure 8 As shown, when the traveling trolley 20 starts to travel, the trolley controller 8 of this embodiment rotates the main body 10 so that the specified direction D of the main body 10 is consistent with the traveling direction (the traveling direction at the start of traveling), thereby making the front surface Mb provided with the cover face in a direction orthogonal to the traveling direction. More specifically, the trolley controller 8 rotates the main body 10 so that the direction in which the first end 12c and the second end 12d of the main body 10 are arranged is roughly consistent with the traveling direction. In other words, the direction in which the pair of anti-sway members 71 / 71 are arranged is roughly consistent with the traveling direction. In other words, the detection direction of the first sensor 61a and the second sensor 61b is roughly consistent with the traveling direction.

[0076] The so-called "when the traveling trolley 20 starts to move" here may include all modes when the transport vehicle 2 starts to move from a stopped state, such as the start of movement after the travel direction of the transport vehicle 2 is switched in the intersection track R3, the start of movement after the transport vehicle 2 completes the transfer operation of the item M, the start of movement after the transport vehicle 2 makes an emergency stop, etc. For example, only the start of movement after the travel direction of the transport vehicle 2 is switched in the intersection track R3 may be included as the object.

[0077] The trolley controller 8 rotates the main body 10 according to the travel direction of the travel trolley 20 when it starts traveling, so that the detection area (the emission direction of the detection light) of one of the first sensor 61a and the second sensor 61b faces the front of the travel direction of the travel trolley 20, and the other of the first sensor 61a and the second sensor 61b cannot detect obstacles. In other words, the trolley controller 8 rotates the main body 10 so that one of the first sensor 61a and the second sensor 61b can detect obstacles in front of the travel direction of the travel trolley 20, and only one of the first sensor 61a and the second sensor 61b that detects obstacles in the front of the travel direction is in a detectable state, and the other of the first sensor 61a and the second sensor 61b that detects obstacles in the rear of the travel direction is in a non-detectable state.

[0078] The trolley controller 8 determines to direct the detection area of ​​one of the first sensor 61a and the second sensor 61b to the front of the travel direction of the traveling trolley 20 based on the information about the direction orthogonal to the travel direction in which the article M will be transferred at the next transfer position. For example, it is assumed that the load port that becomes the next transfer location is arranged on the right side of the travel direction of the transport vehicle 2. In this case, when the traveling trolley 20 starts to travel, the main body 10 is rotated so that the lateral extension direction of the sliding mechanism 11 in the transfer device 18 (the open part of the main frame 12) is directed to the right side of the travel direction. As a result, when the transport vehicle 2 arrives at the next transfer location, the action of rotating the main body 10 in the direction where the load port is arranged can be omitted.

[0079] Figure 3 and Fig. 9 The system controller 5 shown is a computer including a CPU, a ROM, a RAM, etc. The system controller 5 can be configured as software, for example, by loading a program stored in the ROM onto the RAM and executing it by the CPU. The system controller 5 can also be configured as hardware formed by electronic circuits, etc. The system controller 5 can be configured by one device or by a plurality of devices. When configured by a plurality of devices, one system controller 5 is logically constructed by connecting them via a communication network such as the Internet or an intranet. At least a part of the various controls of the system controller 5 can be executed by the trolley controller 8.

[0080] The system controller 5 selects any one of the multiple transport vehicles 2 that can transport the article M, and assigns a transport instruction to the selected transport vehicle 2. The transport instruction includes: a driving instruction, a grabbing instruction, or a unloading instruction; the driving instruction is to make the transport vehicle 2 drive to the load port; the grabbing instruction is to grab the article M configured at the load port; and the unloading instruction is to unload the held article M to the load port.

[0081] The following is an explanation of the effects of the transport vehicle 2 of the above embodiment. In the transport vehicle 2 of the above embodiment, when the main body 10 rotates relative to the traveling carriage 20, the obstacle sensor 61 rotates integrally with the transfer device 18, and the position of the obstacle sensor 61 does not coincide with the direction in which the transfer device 18 delivers the article M. Therefore, in the direction in which the article M is delivered from the transfer device 18, there is no support member for mounting the obstacle sensor 6 to the traveling carriage 20. As a result, the transfer device 18 can deliver the article M in any direction, and the degree of freedom of the transfer position of the article M by the transfer device 18 can be increased.

[0082] The travel carriage 20 of the transport vehicle 2 of the above-described embodiment moves in the first direction by traveling on a pair of first rails R1 / R1 adjacent to each other in the second direction, and moves in the second direction by traveling on a pair of second rails R2 / R2 adjacent to each other in the first direction. In this configuration, the travel carriage 20 can have a higher degree of freedom in terms of the travel direction, and the transfer device 18 can have a higher degree of freedom in terms of the transfer position of the article M.

[0083] The trolley controller 8 of the transport vehicle 2 of the above-mentioned embodiment rotates the main body 10 in a manner such that the detection area of ​​one of the first sensor 61a and the second sensor 61b faces forward in the travel direction of the travel vehicle 20, and makes the other of the first sensor 61a and the second sensor 61b unable to detect obstacles, according to the travel direction of the travel vehicle 20 when the travel vehicle 20 starts to travel. In this way, in the configuration of the above-mentioned embodiment in which two obstacle sensors 6 (the first sensor 61a and the second sensor 61b) are provided on the main body 10, the time required to rotate the main body 10 and to make the detection area of ​​the obstacle sensor 6 face forward in the travel direction of the travel vehicle 20 can be shortened compared to the case in which only one obstacle sensor 6 is provided on the main body 10. In addition, the transport capacity of the transport vehicle 2 can be improved.

[0084] The trolley controller 8 of the transport vehicle 2 of the above embodiment determines which of the detection areas of the first sensor 61a and the second sensor 61b is to be directed forward in the travel direction of the travel vehicle 20, based on information on which direction orthogonal to the travel direction the article M will be transferred in at the next transfer location. This can shorten the time required for the turnaround for transfer after reaching the next transfer location. Furthermore, the transport capacity of the transport vehicle 2 can be improved.

[0085] Although one embodiment has been described above, one aspect of the present invention is not limited to the above embodiment and various modifications can be made without departing from the gist of the present invention.

[0086] In the transport vehicle 2 of the above embodiment, an example of two sensors, namely, a first sensor 61a and a second sensor 61b, as the obstacle sensor 61 has been cited for explanation, but the present invention is not limited thereto. For example, there may be one obstacle sensor 61 provided in the main body 10. In this case, when the traveling vehicle 20 starts to travel, the vehicle controller 8 turns the main body 10 in such a way that the detection area of ​​the obstacle sensor 61 faces the front of the travel direction of the traveling vehicle 20. Thus, no matter where the obstacle sensor 61 is provided in the main body 10, obstacles located in the front of the travel direction can be detected when the transport vehicle 2 is traveling.

[0087] In the transport vehicle 2 of the above embodiment, an example has been given in which the first sensor 61a and the second sensor 61b that detect the rear of the traveling vehicle 20 in the traveling direction when the traveling vehicle 20 starts traveling are disabled from detecting obstacles, but the state in which the obstacle detection is enabled may be maintained. In this case, the vehicle controller 8 may control the traveling vehicle 20 (travel drive motor 33) based only on the detection information of the first sensor 61a and the second sensor 61b that are arranged in front of the traveling vehicle 20 in the traveling direction.

[0088] In the above-mentioned embodiment and the above-mentioned variation example, the transport vehicle 2 has been described by taking an example of having an article pressing mechanism 70 including a pair of anti-swaying members 71 / 71, a pair of article falling members 72 / 72, and a pair of cover falling members 73 / 73, but the pair of anti-swaying members 71 / 71, the pair of article falling members 72 / 72, and the pair of cover falling members 73 / 73 may be provided as at least one set, or none of them may be provided. Even in this case, the orientation of the article M may be fixed relative to the travel direction of the travel vehicle 20, for example, the front surface Mb of the article M may be directed in a direction orthogonal to the travel direction of the transport vehicle 2, and the orientation of the article M may not be fixed relative to the travel direction of the travel vehicle 20.

[0089] In the above embodiment, an overhead transport vehicle 2 is used as an example of a transport vehicle, but an AGV (Automated Guided Vehicle) traveling in a pre-set grid path may be used, or various known systems traveling in a grid path may be used. In addition, in the above embodiment, a transport vehicle 2 holding an article M on the lower side of the track R is used as an example, but a transport vehicle 2 in which the main body 10 is arranged above the track R and holds the article M on the upper side of the track R may also be used.

[0090] In the above embodiment and the above modification, as an example of the track on which the transport vehicle 2 travels, a track in which the first track R1 and the second track R2 are arranged in a grid is described as an example, but a track extending in one direction including a branching portion and a merging portion may also be used.

Claims

1. An overhead transport vehicle, characterized in that: have: Traveling trolley, running on the track; The main body is configured to be rotatable relative to the travel vehicle; A transfer device is disposed on the main body and is configured to deliver the articles in a horizontal direction; and The obstacle sensor is provided in the main body so as not to overlap with the direction in which the transfer device delivers the article, so as to detect an obstacle located in front of the traveling direction of the traveling vehicle.

2. The overhead transport vehicle according to claim 1, characterized in that: In the above-mentioned track in which multiple first rails extending in the first direction and multiple second rails extending in the second direction are arranged in a grid shape, the above-mentioned traveling vehicle moves in the above-mentioned first direction by traveling on a pair of the above-mentioned first rails adjacent to the above-mentioned second direction, and moves in the above-mentioned second direction by traveling on a pair of the above-mentioned second rails adjacent to the above-mentioned first direction, and the above-mentioned second direction is a direction orthogonal to the above-mentioned first direction.

3. The overhead transport vehicle according to claim 1 or 2, characterized in that: And then have: The control unit rotates the main body so that the detection area of ​​the obstacle sensor faces forward in the traveling direction of the traveling vehicle when the traveling vehicle starts traveling.

4. The overhead transport vehicle according to claim 3, characterized in that: The obstacle sensor is configured to include a first sensor and a second sensor, wherein the first sensor is configured to detect the obstacle located on one side of a predetermined direction of the main body, and the second sensor is configured to detect the obstacle located on the other side of the predetermined direction. The control unit rotates the main body in a manner such that the detection area of ​​one of the first sensor and the second sensor faces forward in the driving direction of the traveling vehicle according to the driving direction of the traveling vehicle when the traveling vehicle starts traveling, and makes the other of the first sensor and the second sensor unable to detect the obstacle.

5. The overhead transport vehicle according to claim 4, characterized in that: The control unit determines which detection area of ​​the first sensor or the second sensor is to be directed forward in the traveling direction of the traveling vehicle based on information on which direction orthogonal to the traveling direction the article is to be transferred at the next transfer location.

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