Overhead conveyance vehicle

Abstract

An overhead conveyance vehicle (1) has a travel part (2) and a suspension part (3). The suspension part (3) is provided with: a body frame (4) connected to the travel part (2); a front frame (8A) and a rear frame (8B) attached to both ends of the body frame (4) so as to hang down therefrom; a body part (7) having a holding part (11) for suspending and holding an article (90); a lateral feed part (5) for supporting the body part (7) so as to enable movement in the width direction with respect to the body frame (4); a pair of guide parts (31, 31) respectively provided to the front frame (8A) and the rear frame (8B); and a connection part (35) for connecting the front frame (8A) and the rear frame (8B) below the body frame (4) via the pair of guide parts (31, 31). The connection part (35) moves in accordance with movement of the body part (7) fed out by the lateral feed part (5).

Description

Ceiling transport vehicle

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

[0002]

[0003] Overhead transport vehicles that travel along a track to transport articles are known. For example, Patent Document 1 discloses an overhead transport vehicle that has a front frame extending downward from a front end of a main frame in a traveling direction, and a rear frame extending downward from a rear end of the main frame.

[0003] International Publication No. 2021 / 250976

[0004] However, because the front and rear frames have a cantilever structure relative to the main frame, the lower ends of the front and rear frames tend to move freely and are susceptible to vibrations during travel. In this case, the components of the overhead transport vehicle may come into contact with each other, or with components arranged around the track, potentially damaging the components of the overhead transport vehicle.

[0005] SUMMARY OF THE INVENTION It is therefore an object of one aspect of the present invention to provide an overhead transport vehicle that can reduce vibrations that occur in the front and rear frames that hang down from the main body frame.

[0006] (1) An overhead transport vehicle according to one aspect of the present invention is an overhead transport vehicle having a running section that runs along a track and a hanging section suspended from the running section, and that transfers items to a transfer location located below the track, wherein the hanging section comprises a main body frame connected to the running section, a front frame and a rear frame that are attached so as to hang down from both ends of the main body frame in the running direction of the running section, a main body section that is arranged between the front frame and the rear frame in the running direction and has a holding section that hangs and holds an item, a lateral feed section that supports the main body section relative to the main body frame so that it can move in a width direction perpendicular to the running direction, a pair of guide sections provided on the front frame and the rear frame, respectively, and a connecting section that connects the front frame and the rear frame below the main body frame via the pair of guide sections, and the connecting section moves in accordance with the movement of the main body section sent out by the lateral feed section.

[0007] In an overhead transport vehicle with this configuration, the front and rear frames are directly or indirectly connected below the main frame without interfering with the transfer of items to the transfer location. This allows the movement of the lower ends of the front and rear frames to be restricted more effectively than with cantilevered front and rear frames. As a result, vibrations generated in the front and rear frames hanging down from the main frame can be reduced.

[0008] (2) In the overhead transport vehicle of (1) above, the connecting portion is a member that connects the front frame and the rear frame via a pair of guide portions and a pair of connecting portions that connect each of the pair of guide portions to the main body portion, and may be configured as a part of the main body portion to which the pair of connecting portions are fixed. In this configuration, the connecting portion can be moved in accordance with the movement of the main body portion sent out by the lateral feed portion without providing a dedicated drive unit. This allows the connecting portion to be moved with a simple configuration.

[0009] (3) In the overhead transport vehicle of (2), the coupling portion may further include a reinforcing member connecting the pair of connecting portions. With this configuration, the front frame and the rear frame can be more firmly isolated from vibrations.

[0010] (4) In the ceiling transport vehicle of (3), the reinforcing member may be disposed laterally in the width direction of the article suspended and held by the holding portion. In this configuration, the front frame and the rear frame can be more firmly isolated from vibrations.

[0011] (5) In the overhead transport vehicle of (3) or (4), the reinforcing member may be a plate-shaped member having a main surface perpendicular to the width direction. This configuration allows the front frame and the rear frame to be more firmly and stably isolated from vibrations.

[0012] (6) In any one of the above-mentioned (3) to (5), the overhead transport vehicle is configured to transfer an article to a transfer location located to the side of the track, and the reinforcing member may be positioned higher than the top of the article placed at the transfer location when the suspension part is stopped to the side of the transfer location. In this configuration, the reinforcing member can be positioned without interfering with the transfer of the article to the transfer location located to the side of the track (the action of going to the transfer location to pick up the article, and the action of returning to the original position after placing the article at the transfer location).

[0013] (7) In the overhead transport vehicle according to any one of (1) to (6), the pair of guide portions may be provided on the front and rear frames, on surfaces where the front and rear frames face each other. This configuration allows for a compact structure to reduce vibrations generated in the front and rear frames.

[0014] (8) In any one of the ceiling transport vehicles (1) to (7) above, the main body may be provided with a sway detection sensor. In this configuration, the main body, the front frame, and the rear frame are fixed by a pair of guide parts and a pair of connecting parts. This makes it difficult for the main body to tilt due to its own weight and the weight of the article even when the main body is transported laterally by the lateral feed part, thereby preventing erroneous detection by the sway detection sensor.

[0015] (9) In any one of the ceiling transport vehicles (1) to (8) above, the lateral feed unit may support the main body unit so that it can move on both the left and right sides of the main body frame, i.e., on one side in the width direction, i.e., the left side, and the other side in the width direction, i.e., the right side. When the main body unit is lateral fed (moved) in both the left and right directions between the front frame and the rear frame, both sides of the normal position directly below the main body frame become the movement area of ​​the main body unit. In this movement area, it is not possible to place a reinforcing member or the like that simply connects the front frame and the rear frame, and vibrations generated in the front frame and the rear frame increase. In this configuration, even if vibrations generated in the front frame and the rear frame are particularly large in a conventional configuration, the front frame and the rear frame are reinforced by the connecting member that moves in accordance with the movement of the main body unit fed by the lateral feed unit, so that vibrations generated in the front frame and the rear frame can be reduced.

[0016] According to one aspect of the present invention, it is possible to suppress vibrations occurring in the front frame and rear frame hanging down from the main body frame.

[0017] FIG. 1 is a schematic side view of an overhead transport vehicle according to an embodiment. FIG. 2 is a perspective view of the main body frame of the overhead transport vehicle of FIG. 1, as viewed obliquely from above. FIG. 3 is a front view of the main body frame of the overhead transport vehicle of FIG. 1, as viewed from the front. FIG. 4 is a front view of the main body frame of the overhead transport vehicle of FIG. 1, as viewed from the front, with the lifting unit moved laterally to the left. FIG. 5(A) is a perspective view of the main body frame of the overhead transport vehicle of FIG. 1, as viewed obliquely from the rear, with the lifting unit moved laterally to the left. FIG. 5(B) is a perspective view of the main body frame of the overhead transport vehicle of FIG. 1, as viewed obliquely from the rear, with the lifting unit moved laterally to the right. FIG. 6 is a perspective view of a side buffer and the main body frame of the overhead transport vehicle of FIG. 1, as viewed from the rear left. FIG. 7 is a side view of the side buffer and the main body frame of the overhead transport vehicle of FIG. 1, as viewed from the left. FIG. 8 is a perspective view of the main body frame of a modified overhead transport vehicle, as viewed obliquely from above. FIG. 9(A) is a perspective view of the main body frame of the overhead transport vehicle of FIG. 8, as viewed obliquely from the rear, with the lifting unit moved laterally to the left. FIG. 9B is a perspective view of the main body frame of the ceiling transport vehicle of FIG. 8 when viewed obliquely from behind, with the lifting unit being laterally fed to the right.

[0018] Hereinafter, an overhead transport vehicle 1 according to one embodiment 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 explanations will be omitted.

[0019] As shown in FIG. 1 , the ceiling transport vehicle 1 travels along a traveling rail (track) R installed at a position higher than the floor, such as the ceiling of a clean room. The ceiling transport vehicle 1 transports an item 90, for example, between a storage facility and a predetermined load port. Examples of the item 90 include containers such as FOUPs (Front Opening Unified Pods) that store multiple semiconductor wafers and reticle pods that store glass substrates, as well as general parts. The item 90 in the above embodiment is a FOUP, which has a flange 90A that is held by the ceiling transport vehicle 1. The ceiling transport vehicle 1 includes a running section 2 and a hanging section 3.

[0020] The traveling unit 2 has a front traveling body 2A and a rear traveling body 2B. A connecting portion 2D provided on the front traveling body 2A and a connecting portion 2D provided on the rear traveling body 2B are rotatably connected by a connecting shaft 2E. Traveling rollers 2C, 2C and traveling drive units 2M, 2M are provided on the front traveling body 2A and the rear traveling body 2B, respectively. In this embodiment, the traveling drive unit 2M is an LDM (Linear DC Motor) that accelerates or brakes the overhead transport vehicle 1 by magnetic force generated between the traveling rollers 2C and a magnetic plate arranged on the upper surface of the traveling rail R.

[0021] The suspension part 3 is suspended from the running part 2. More specifically, a pair of suspension members 2F, 2F extending vertically downward from the running part 2 are connected to a main body frame 4 of the suspension part 3, thereby suspension part 3 is suspended from the running part 2. The suspension part 3 has the main body frame 4, a horizontal drive unit (cross feed unit) 5, a rotation drive unit 6, an elevation drive unit 7, an elevation unit (main body) 10, a front frame 8A, a rear frame 8B, a controller 80, and a frame vibration isolation mechanism 30.

[0022] The horizontal drive unit 5 is fixed to the lower part of the main frame 4. The horizontal drive unit 5 moves the rotation drive unit 6, the lift drive unit 7, and the lift section 10 in a direction (width direction / left / right direction) perpendicular to the extending direction of the traveling rail R within a horizontal plane, and feeds them laterally on both the left and right sides of the main frame 4 (see FIGS. 5A and 5B). The rotation drive unit 6 rotates the lift drive unit 7 and the lift section 10 within a horizontal plane.

[0023] The lifting drive unit 7 has a housing 7A rotatably fixed to the rotation drive unit 6, and a lifting mechanism 7B that raises and lowers the lifting section 10. The lifting mechanism 7B raises and lowers the lifting section 10 by winding up and unwinding four belts 9. The belts 9 in the lifting mechanism 7B may be replaced by any suitable suspending member such as a wire or rope.

[0024] A vibration detection sensor 17 is provided on the housing 7A of the lifting drive unit 7. The vibration detection sensor 17 emits a detection wave downward. The vibration detection sensor 17 is not particularly limited, but may be, for example, a laser range finder. The vibration detection sensor 17 emits a directional detection wave toward the upper surface of the lifting unit 10 and receives the reflected wave reflected by a reflector 17A provided on the upper surface of the lifting unit 10. The light reception result by the vibration detection sensor 17 is acquired by the controller 80.

[0025] The lifting section 10 is movable up and down by the lifting drive unit 7 and functions as a lifting platform in the ceiling transport vehicle 1. The lifting section 10 has a holding device (holding section) 11 that grips an article 90, and is raised and lowered by a belt 9 relative to the horizontal drive unit 5, the rotation drive unit 6, and the lifting drive unit 7, which serve as main bodies. The lifting section 10 is disposed between the front frame 8A and the rear frame 8B in the traveling direction. The holding device 11 holds the article 90. The holding device 11 includes a pair of L-shaped arms 12, 12, claws 13, 13 fixed to each arm 12, 12, and an opening / closing mechanism 15 that opens and closes the pair of arms 12, 12.

[0026] The opening / closing mechanism 15 moves the pair of arms 12, 12 in directions toward and away from each other. The pair of arms 12, 12 advance and retreat in the front-to-rear direction by the operation of the opening / closing mechanism 15. This causes the pair of claws 13, 13 fixed to the arms 12, 12 to open and close.

[0027] In this embodiment, the height position of the holding device 11 (lifting unit 10) is adjusted so that when the pair of claws 13, 13 are in an open state, the holding surfaces of the claws 13 are lower than the height of the lower surface of the flange 90A. Then, when the pair of claws 13, 13 are in a closed state in this state, the holding surfaces of the claws 13, 13 advance below the lower surface of the flange 90A, and when the lifting unit 10 is raised in this state, the flange 90A is held (gripped) by the pair of claws 13, 13, and the article 90 is supported.

[0028] A reflector 17A is provided on the lifting / lowering unit 10. The reflector 17A is provided on the upper surface of the lifting / lowering unit 10. The reflector 17A reflects the detection wave from the vibration detection sensor 17. The reflector 17A is disposed with its reflective surface facing upward, and reflects the detection wave from above upward. The reflector 17A is disposed directly below the vibration detection sensor 17 when the lifting / lowering unit 10 is in a horizontal position.

[0029] The front frame 8A and the rear frame 8B are provided at the front and rear in the travel direction so as to cover the horizontal drive unit 5, the rotation drive unit 6, the lift drive unit 7, the lifting section 10, and the holding device 11. The front frame 8A and the rear frame 8B are attached so as to hang down from both ends of the main frame 4 in the travel direction of the traveling section 2. The front frame 8A and the rear frame 8B form a space below the holding device 11 in which an article 90 can be stored when the lifting section 10 is raised to its upper end.

[0030] The controller 80 is an electronic control unit including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), etc. The controller 80 controls various operations of the ceiling transport vehicle 1. Specifically, the controller 80 controls the traveling section 2, the horizontal drive unit 5, the rotation drive unit 6, and the lift drive unit 7. The controller 80 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 controller 80 may also be configured as hardware including electronic circuits, etc. The controller 80 communicates with a higher-level controller (not shown) using a power supply section (power supply line or feeder line) of the traveling rail R, etc.

[0031] The frame vibration isolation mechanism 30 is a mechanism that reduces vibrations generated in the front frame 8A and the rear frame 8B. As shown in Figures 2 to 4, the frame vibration isolation mechanism 30 includes a pair of guide portions 31, 31, a pair of connecting portions 33, 33, a linking portion 35, and a reinforcing member 37.

[0032] The pair of guide portions 31, 31 are provided on the front frame 8A and the rear frame 8B, respectively. Each of the pair of guide portions 31, 31 moves the connecting portion 35 and the reinforcing member 37 along the width direction in accordance with the movement of the housing 7A in the width direction of the lifting drive unit 7. The pair of guide portions 31, 31 are provided on opposing surfaces 8Aa, 8Ba of the front frame 8A and the rear frame 8B where the front frame 8A and the rear frame 8B face each other.

[0033] The front frame 8A and the rear frame 8B may each be configured with a metal plate and a resin frame. More specifically, one surface of each metal plate configuring the front frame 8A and the rear frame 8B forms an opposing surface 8Aa, 8Ba to which a pair of guide portions 31, 31 are fixed, and electronic components are fixed to the other surface of each metal plate. The resin frame is formed to cover the electronic components fixed to the other surface of the metal plate. It is preferable that the guide portions 31, 31 and the connecting portion 35 are configured to connect the rigid metal plates together.

[0034] In this embodiment, each of the pair of guide sections 31, 31 is composed of three members: a first guide member 31A, a second guide member 31B, and a third guide member 31C, which are slidable relative to one another in the width direction. The first guide member 31A, the second guide member 31B, and the third guide member 31C are rectangular prism members made of, for example, aluminum or stainless steel. More specifically, the first guide member 31A and the second guide member 31B are configured to be slidable relative to one another by linear guides. Similarly, the second guide member 31B and the third guide member 31C are configured to be slidable relative to one another by linear guides. With this configuration, each of the pair of guide sections 31, 31 is configured to be extendable and contractible in the width direction.

[0035] The pair of connecting portions 33, 33 connect each of the pair of guide portions 31, 31 to the housing 7A of the lifting / lowering drive unit 7. Each of the pair of connecting portions 33, 33 is composed of a first connecting member 33A and a second connecting member 33B. The first connecting member 33A and the second connecting member 33B are strip-shaped plate members made of, for example, aluminum or stainless steel. The lower end of the first connecting member 33A is connected to one end (left end) of the third guide member 31C in the width direction. The upper end of the first connecting member 33A is connected to the upper end of the housing 7A of the lifting / lowering drive unit 7. The lower end of the second connecting member 33B is connected to the other end (right end) of the third guide member 31C in the width direction. The upper end of the second connecting member 33B is connected to the upper end of the housing 7A of the lifting / lowering drive unit 7.

[0036] The connecting portion 35 connects the front frame 8A and the rear frame 8B below the main body frame 4 via a pair of guide portions 31. The connecting portion 35 moves in accordance with the movement of the housing 7A of the lifting drive unit 7, which is advanced by the horizontal drive unit 5. The connecting portion 35 in this embodiment is a member that connects the front frame 8A and the rear frame 8B via each of the pair of guide portions 31 and each of the pair of connection portions 33, and is formed by a part 7Aa of the housing 7A of the lifting drive unit 7 to which the pair of connection portions 33 is fixed. In other words, the front frame 8A and the rear frame 8B are connected below the main body frame 4 by one guide portion 31, one connection portion 33, the part 7Aa of the housing 7A of the lifting drive unit 7, the other connection portion 33, and the other guide portion 31.

[0037] The linking section 35 of this embodiment is configured to further include a reinforcing member 37 that connects the pair of connecting sections 33, 33 together. The reinforcing member 37 is arranged on both sides in the width direction of the article 90 that is suspended and held by the holding device 11 of the lifting section 10. The reinforcing member 37 has a main surface 37A that is perpendicular to the width direction and is a plate-like member made of, for example, aluminum or stainless steel. The reinforcing member 37 is attached to a portion of the pair of connecting sections 33, 33 in the vertical direction.

[0038] Here, a brief description will be given of the side buffer 50. As shown in Figures 6 and 7 , the side buffers 50 are disposed on both sides in the width direction (Y direction) of the hanging portion 3 that travels on the traveling rail R. The side buffer 50 forms a loading shelf (transfer location) 54 onto which articles 90 can be transferred when the horizontal drive unit 5 of the hanging portion 3 moves the rotation drive unit 6, the lift drive unit 7, and the lift section 10 in the width direction, and then the lift drive unit 7 raises and lowers the lift section 10. The side buffer 50 has a pair of first hanging portions 51, 51, a first connection portion 52, a second connection portion 53, the loading shelf 54, and a fall prevention fence 55.

[0039] The pair of first suspending portions 51, 51 are suspended members extending from a fixed portion such as a ceiling. They are arranged at equal intervals in the extension direction (X direction) of the traveling rail R. The first connecting portion 52 connects the lower end of one of the pair of first suspending portions 51, 51 to the lower end of the other of the pair of first suspending portions 51, 51. The second connecting portion 53, located above the first connecting portion 52, connects one of the pair of first suspending portions 51, 51 to the other of the pair of first suspending portions 51, 51.

[0040] The loading shelf 54 is suspended between one pair of adjacent first connection portions 52 in the X direction. The loading shelf 54 is a plate-shaped member on which the item 90 is placed. The loading shelf 54 may be provided with a loading portion 54A (see FIG. 7 ) provided with a positioning pin for determining the position where the item 90 is placed. The fall prevention fence 55 is a flat straddling member suspended between adjacent first hanging portions 51, 51. The fall prevention fence 55 is arranged so as to sandwich the item 90 placed on the loading shelf 54 from the side (Y direction). In other words, the fall prevention fence 55 is arranged to prevent the item 90 placed on the loading shelf 54 from falling from the loading shelf 54.

[0041] The operation of the ceiling transport vehicle 1 when an article 90 placed on the loading shelf 54 (loading section 54A) of the side buffer 50 is grasped by the holding device 11 of the lifting section 10 will be described. The ceiling transport vehicle 1 stops to the side of the loading shelf 54 (loading section 54A) of the side buffer 50 to be transferred. Next, the horizontal drive unit 5 laterally transports the rotation drive unit 6, the lifting drive unit 7, and the lifting section 10 in the width direction (Y direction), and the rotation drive unit 6, the lifting drive unit 7, and the lifting section 10 move above the article 90 placed on the side buffer 50. Next, the lifting drive unit 7 moves the lifting section 10 downward, and the holding device 11 of the lifting section 10, which has moved downward to a predetermined position, grasps the flange 90A of the article 90.

[0042] The reinforcing member 37 is disposed at a height position H2 higher than a height position H1 of the upper end of the article 90 placed on the side buffer 50 when the hanging portion 3 of the ceiling transport vehicle 1 is stopped to the side of the loading shelf 54 (loading portion 54A) to which the side buffer 50 is to transfer the article 90. In other words, the height position H2 of the lower end of the reinforcing member 37 is disposed above a height position H1 of the upper end (upper end of the flange 90A) of the article 90 placed on the side buffer 50. Therefore, even if the horizontal drive unit 5 laterally feeds the rotation drive unit 6, the lifting drive unit 7, and the lifting portion 10 in the width direction (Y direction) to move the article 90 above the side buffer 50, the upper end of the article 90 placed on the side buffer 50 does not come into contact with the lower end of the reinforcing member 37. The lifting portion 10, which has been moved above the article 90 placed on the side buffer 50, is then moved downward by the lifting drive unit 7, thereby being able to hold the article 90 placed on the side buffer 50.

[0043] The effects of the overhead transport vehicle 1 of the above embodiment will be described. In the overhead transport vehicle 1 of the above embodiment, the front frame 8A and the rear frame 8B are indirectly connected below the main frame 4 by a pair of guide portions 31, 31, a pair of connecting portions 33, 33, and a portion 7Aa of the housing 7A of the lifting drive unit 7, without interfering with the transfer of the article 90 to the transfer location (movement of the housing 7A in the lifting drive unit 7 during transfer). This makes it possible to restrict movement of the lower ends of the front frame 8A and the rear frame 8B compared to the front frame 8A and the rear frame 8B having a cantilever beam configuration. As a result, vibrations generated in the front frame 8A and the rear frame 8B hanging from the main frame 4 can be reduced.

[0044] In the ceiling transport vehicle 1 of the above embodiment, the coupling portion 35 is formed by a part 7Aa of the housing 7A of the lifting drive unit 7 to which the pair of connecting portions 33, 33 are fixed. The part 7Aa of the housing 7A of the lifting drive unit 7 is also a member that connects the front frame 8A to the rear frame 8B via the pair of guide portions 31, 31 and the pair of connecting portions 33, 33 that connect each of the pair of guide portions 31, 31 to the housing 7A of the lifting drive unit 7. This allows the coupling portion 35 to move in accordance with the movement of the housing 7A of the lifting drive unit 7 advanced by the horizontal drive unit 5, without requiring a dedicated drive unit for moving the coupling portion 35 in accordance with the movement of the housing 7A of the lifting drive unit 7 advanced by the horizontal drive unit 5. This allows the coupling portion 35 to be moved with a simple configuration.

[0045] In the ceiling transport vehicle 1 of the above embodiment, the connecting portion 35 further includes a reinforcing member 37 that connects the pair of connecting portions 33, 33 together. This allows the front frame 8A and the rear frame 8B to be more firmly vibration-damped. Furthermore, the reinforcing member 37 is disposed on both sides in the width direction of the article 90 suspended and held by the holding device 11. This allows the front frame 8A and the rear frame 8B to be even more firmly vibration-damped. Furthermore, the reinforcing member 37 is a plate-shaped member having a main surface 37A that is perpendicular to the width direction. This allows the front frame 8A and the rear frame 8B to be more firmly and stably vibration-damped.

[0046] In the ceiling transport vehicle 1 of the above embodiment, when the suspension unit 3 is stopped to the side of the transfer location, the reinforcing member 37 is positioned higher than the upper end of the article 90 placed on the loading shelf 54 (loading section 54A) of the side buffer 50. This allows the reinforcing member 37 to be positioned without interfering with the transfer of the article 90 to the loading shelf 54 located to the side of the traveling rail R (the action of going to retrieve the article 90 from the loading shelf 54, and the action of returning to the designated position after placing the article 90 on the loading shelf 54).

[0047] In the overhead transport vehicle 1 of the above embodiment, the pair of guide portions 31, 31 are provided on the opposing surfaces 8Aa, 8Ba of the front frame 8A and the rear frame 8B where the front frame 8A and the rear frame 8B face each other. This allows for a compact configuration and reduces vibrations generated in the front frame 8A and the rear frame 8B.

[0048] In the ceiling transport vehicle 1 of the above embodiment, the lifting drive unit 7 is provided with a sway detection sensor 17, and the lifting drive unit 7, the front frame 8A, and the rear frame 8B are fixed together by a pair of guide portions 31, 31 and a pair of connecting portions 33, 33. This makes it difficult for the lifting drive unit 7 to tilt due to its own weight and the weight of the article, even when the lifting drive unit 7 is moved laterally by the horizontal drive unit 5, thereby preventing erroneous detection by the sway detection sensor 17.

[0049] Although one embodiment has been described above, one aspect of the present invention is not limited to the above embodiment, and various modifications are possible without departing from the spirit of the invention.

[0050] In the above embodiment, the ceiling transport vehicle 1 has been described as having a configuration in which the pair of guides 31, 31, the pair of connectors 33, 33, and the coupling 35 are linked to the movement of the housing 7A of the lift drive unit 7, which is moved laterally by the horizontal drive unit 5. However, this is not limiting. For example, instead of removing the pair of connectors 33, 33 from the configuration of the ceiling transport vehicle 1 of the above embodiment, an actuator that expands and contracts the pair of guides 31, 31 in accordance with the horizontal movement of the lift drive unit 7 and a coupling that directly connects the pair of guides 31, 31 to each other may be provided. Even with this configuration, as with the ceiling transport vehicle 1 of the above embodiment, the movement of the lower ends of the front frame 8A and the rear frame 8B can be restricted without interfering with the transfer of the article 90 to the transfer location. As a result, vibrations generated in the front frame 8A and the rear frame 8B hanging from the main frame 4 can be reduced.

[0051] In the above embodiment and modified example, the reinforcing member 37 of the ceiling transport vehicle 1 is positioned higher than the upper end of the article 90 placed on the loading shelf 54 of the side buffer 50 when the suspension unit 3 is stopped to the side of the transfer location, as shown in FIG. 2 . However, the position, size, and shape of the reinforcing member 37 are not limited to the embodiment shown in FIG. 2 . For example, as shown in FIGS. 8 , 9A, and 9B , the reinforcing member 37 may be larger than the reinforcing member 37 shown in FIG. 2 and positioned lower. Even in this case, transfer to the loading shelf 54 is possible as long as the loading shelf 54 of the side buffer 50 is positioned lower than the position shown in FIG. 7 . If it is desired to load the article 90 onto the loading shelf 54 without lowering the lifting unit 10 too much after the horizontal drive unit 5 has laterally transported the housing 7A of the lifting drive unit 7, it is advantageous to position the reinforcing member 37 at the position shown in FIG. 2 .

[0052] 2 and 7, the reinforcing member 37 of the ceiling transport vehicle 1 in the above embodiment and the above modified example has been described as being formed of a plate-like member having a main surface 37A in the width direction, but it may also be a rectangular pillar-like member, for example. Also, the reinforcing member 37 may be removed from the configuration of the ceiling transport vehicle 1 in the above embodiment and the above modified example.

[0053] 3 and 4, the reinforcing members 37 of the ceiling transport vehicle 1 in the above embodiment and the above modified example are arranged on both sides in the width direction of the article 90 suspended and held by the holding device 11 of the lifting unit 10, but they may be arranged on only one side. In this case, it is possible to reduce the vibration generated in the front frame 8A and the rear frame 8B while making the ceiling transport vehicle 1 lighter than in the above embodiment.

[0054] In the above embodiment, the horizontal drive unit 5 of the ceiling transport vehicle 1 has been described as being configured to allow the rotation drive unit 6, the lift drive unit 7, and the lift unit 10 to be laterally moved to both the left and right of the main frame 4. However, the horizontal drive unit 5 may be configured to allow only one of the left and right directions to be laterally moved. Furthermore, in this modified configuration, in the configuration of the ceiling transport vehicle 1 of the above embodiment, which includes the guide unit 31, the connection unit 33, and the reinforcing member 37, a connecting reinforcing member directly connecting the front frame 8A and the rear frame 8B may be added to the side where the rotation drive unit 6, the lift drive unit 7, and the lift unit 10 are not laterally moved, and the reinforcing member 37 on the side where the rotation drive unit 6, the lift drive unit 7, and the lift unit 10 are not laterally moved may be removed (the reinforcing member 37 may be provided only on the side where the rotation drive unit 6, the lift drive unit 7, and the lift unit 10 are laterally moved). Even in this modified configuration, the reinforcing member 37 can reduce vibrations generated in the front frame 8A and the rear frame 8B on the side where the connecting reinforcing member is not present.

[0055] Although the pair of guide portions 31, 31 of the ceiling transport vehicle 1 in the above embodiment and the above modified example have been described as being arranged on the pair of opposing surfaces 8Aa, 8Ba, the present invention is not limited to this. The pair of guide portions 31, 31 may be arranged on the front surface of the front frame 8A and the rear surface of the rear frame 8B (i.e., on the outer surfaces of the front frame 8A and the rear frame 8B in the traveling direction). In this case, the overall size of the frame vibration isolation mechanism 30 increases compared to when the pair of guide portions 31, 31 are arranged on the pair of opposing surfaces 8Aa, 8Ba, but the same effects as those of the above embodiment can be obtained.

[0056] 1...ceiling transport vehicle, 2...running section, 3...hanging section, 4...main body frame, 5...horizontal drive unit (cross feed section), 6...rotational drive unit, 7...lifting drive unit (main body section), 7A...housing, 7Aa...part of the housing, 8A...front frame, 8B...rear frame, 8Aa, 8Ba...opposing surface, 10...lifting section, 11...holding device (holding section), 17...vibration detection sensor, 17A...reflector, 30...frame vibration isolation mechanism, 31...guide section, 31A...first guide member, 31B...second guide member, 31C...third guide member, 33...connecting section, 33A...first connecting member, 33B...second connecting member, 35...coupling section, 37...reinforcing member, 37A...main surface, 50...side buffer, 54...loading shelf, 54A...loading section, 90...article, 90A...flange, R...running rail (track).

Claims

1. An overhead transport vehicle having a running section that runs along a track and a hanging section suspended from the running section, for transferring items to a transfer location located below the track, wherein the hanging section comprises: a main body frame connected to the running section; a front frame and a rear frame attached so as to hang down from both ends of the main body frame in the running direction of the running section; a main body section that is arranged between the front frame and the rear frame in the running direction and has a holding section that hangs and holds the item; a lateral feed section that supports the main body section relative to the main body frame so that it can move in a width direction perpendicular to the running direction; a pair of guide sections provided on the front frame and the rear frame, respectively; and a connecting section that connects the front frame and the rear frame below the main body frame via the pair of guide sections, wherein the connecting section moves in accordance with the movement of the main body section sent out by the lateral feed section.

2. The overhead transport vehicle of claim 1, wherein the connecting portion is a member that connects the front frame and the rear frame via the pair of guide portions and a pair of connecting portions that connect each of the pair of guide portions to the main body portion, and is constituted by a part of the main body portion to which the pair of connecting portions are fixed.

3. The overhead transport vehicle according to claim 2, wherein the connecting portion further includes a reinforcing member connecting the pair of connecting portions together.

4. The overhead transport vehicle according to claim 3, wherein the reinforcing member is disposed laterally in the width direction of the article suspended and held by the holding portion.

5. The overhead transport vehicle according to claim 3 or 4, wherein the reinforcing member is a plate-like member having a main surface perpendicular to the width direction.

6. A ceiling transport vehicle as described in claim 3 or 4, which transfers the item to a transfer location located to the side of the track, wherein the reinforcing member is positioned at a position higher than the upper end of the item placed at the transfer location when the hanging part is stopped to the side of the transfer location.

7. An overhead transport vehicle according to any one of claims 1 to 4, wherein the pair of guide portions are provided on the surfaces of the front frame and the rear frame where the front frame and the rear frame face each other.

8. An overhead transport vehicle according to any one of claims 1 to 4, wherein the main body is provided with a vibration detection sensor.

9. An overhead transport vehicle as claimed in any one of claims 1 to 4, wherein the lateral feed section supports the main body frame so that the main body can move on both the left and right sides of the main body frame, that is, on one side of the width direction, i.e., the left side, and the other side of the width direction, i.e., the right side.

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