Overhead transport vehicle

Abstract

The main body (3) of the aerial transport vehicle (1) that holds the transported object (90) is suspended and supported on the traveling unit (2). The aerial transport vehicle (1) includes: a base (23) that is suspended on the traveling unit (2); a support (21) that is disposed on the main body (3) and is rotatably supported on the base (23) by means of a rotating shaft (26) extending in the horizontal direction; and a pair of shock absorbers (30, 30) that are disposed such that they sandwich the rotating shaft (26) in a second direction orthogonal to both the first direction and the vertical direction extending from the rotating shaft (26) and are configured to contact the main body (3).

Description

Technical Field

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

[0002] Patent Document 1 discloses an unmanned transport vehicle, which includes a trolley, an unmanned transport vehicle body mounted on the trolley using vibration dampers, and a transfer device mounted on the unmanned transport vehicle body. In the unmanned transport vehicle of Patent Document 1, vibrations transmitted to items during movement can be reduced.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2001-298065 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] However, according to the existing unmanned transport vehicles described above, although the vibration transmitted to the items (the transported objects) can be reduced during operation, the transported objects sometimes sway. In particular, in aerial transport vehicles configured to suspend the main body of the transported object from the traveling unit, the swaying of the transported object becomes greater.

[0008] Therefore, one aspect of the present invention is to provide an aerial transport vehicle capable of suppressing the propagation of vibrations from the traveling unit to the transported object and suppressing the swaying of the transported object.

[0009] Methods for solving problems

[0010] An aerial transport vehicle of one aspect of the present invention suspends the main body of the transported object on a traveling unit. The aerial transport vehicle includes: a base portion suspended from the traveling unit; a support portion disposed on the main body portion and rotatably supporting the base portion by means of a rotating shaft extending in the horizontal direction; and a pair of shock absorbers disposed on the base portion in a manner that clamps the rotating shaft in a second direction orthogonal to both a first direction and a vertical direction extending from the rotating shaft, and configured to contact the main body portion.

[0011] In this overhead conveyor, vibrations propagating from the traveling section are absorbed by a base that is rotatably supported on the main body, and the relative positional relationship between the main body and the traveling section (the orientation of the main body relative to the traveling section) is stably maintained by a shock absorber. As a result, the propagation of vibrations from the traveling section to the transported object is suppressed, and the swaying of the transported object is also suppressed.

[0012] In one aspect of the aerial transport vehicle of the present invention, the rotating shaft may be arranged to extend in a direction orthogonal to both the travel direction and the vertical direction of the traveling unit, and is disposed at the center of the main body in the travel direction of the traveling unit. A pair of shock absorbers are provided to sandwich the rotating shaft in the travel direction of the traveling unit. In this configuration, when the angle of the traveling unit is allowed to change relative to the main body, since the angle change is allowed only in the travel direction of the traveling unit, the tilt of the main body can be kept to a minimum when the transported object is transferred in a left-right (lateral) direction orthogonal to the travel direction.

[0013] In one aspect of the aerial transport vehicle of the present invention, the base may be suspended from the travel unit by means of a pair of suspension members extending downward in a vertical direction from the travel unit, and the base may be able to support the suspension members rotatably about an axis about the extending direction of the suspension members. In this configuration, torsional stress generated between the mounting portion of the suspension members toward the travel unit and the mounting portion toward the base unit can be suppressed.

[0014] Alternatively, in one aspect of the invention, the traveling unit of the aerial transport vehicle has a driving unit that accelerates or brakes the traveling unit by generating magnetic force between it and a magnetic plate disposed on the traveling track. In an aerial transport vehicle with such a driving unit, since the electromagnet (LDM: Linear DC Motor) which is part of the driving unit is disposed with a small gap between it and the magnetic plate, if the traveling unit is lifted upward due to a change in the attitude of the main body, the driving unit may collide with the magnetic plate. In this configuration of the aerial transport vehicle, since the shock absorber that directly contacts the main body and the suspension component connected to the traveling unit are disposed in a manner that do not overlap each other when viewed from above, it is possible to suppress the direct lifting of the traveling unit by a change in the attitude of the main body. As a result, the possibility of the driving unit colliding with the magnetic plate can be reduced.

[0015] In one aspect of the aerial transport vehicle of the present invention, the shock absorber may also include a rubber component and a spring component. In this configuration, since the pressure generated by the shock absorber can be easily adjusted by compressing the spring component, the relative positional relationship between the main body and the traveling unit can be maintained more stably.

[0016] In one aspect of the aerial transport vehicle of the present invention, the support portion may rotatably support the rotating shaft by means of a rubber bushing. According to this configuration, not only can the propagation of vibrations in the rotational direction of the rotating shaft be effectively suppressed, but also the propagation of vibrations in other directions, such as vibrations from the traveling unit, to the transported object can be effectively suppressed.

[0017] Invention Effects

[0018] According to one aspect of the invention, it is possible to suppress the propagation of vibrations from the traveling unit to the conveyed object and to suppress the swaying of the conveyed object. Attached Figure Description

[0019] Figure 1 This is a side view of one implementation of an aerial transport vehicle.

[0020] Figure 2 Viewed from an oblique angle Figure 1 A 3D view of the main frame of the aerial transport vehicle.

[0021] Figure 3 This is a three-dimensional view of the vibration damping unit viewed from an oblique angle.

[0022] Figure 4 This is a side view of the vibration damping unit.

[0023] Figure 5 It is a cross-sectional view of the vibration damping unit cut along the front-to-back direction.

[0024] Figure 6 It is a cross-sectional perspective view showing the internal structure of the shock absorber.

[0025] Figure 7 (A) and Figure 7 (B) are diagrams illustrating the operation of a pressurized shock absorber. Detailed Implementation

[0026] Hereinafter, an embodiment of the aerial transport vehicle 1 will be described with reference to the accompanying drawings. In the description of the drawings, the same reference numerals are used to refer to the same elements, and repeated descriptions are omitted.

[0027] Figure 1 The overhead transport vehicle 1 shown travels along a track R positioned at a height equal to or above the ground level on the ceiling of the cleanroom. The overhead transport vehicle 1 transports items 90 between storage equipment and designated loading ports, for example. Examples of items 90 include containers such as FOUPs (Front Opening Unified Pods) for storing multiple semiconductor wafers and reticule pods for storing glass substrates, as well as general components. These containers have flanges 98 that hold them in place on the overhead transport vehicle 1.

[0028] In the following explanation, for ease of explanation, Figure 1 The left-right direction (X-axis direction) is set as the front-back direction (second direction) of the aerial transport vehicle 1. Figure 1 The vertical direction (Z-axis direction) is set as the vertical direction (vertical direction) of the overhead conveyor 1. Figure 1The depth direction (Y-axis direction) is set as the left-right direction or the width direction (first direction) of the aerial transport vehicle 1. The X-axis direction, Y-axis direction and Z-axis direction are orthogonal to each other.

[0029] like Figure 1 and Figure 2 As shown, the aerial transport vehicle 1 includes a traveling unit 2, a main body 3, and a lifting unit 10. The traveling unit 2 moves the aerial transport vehicle 1 along the travel track R. The traveling unit 2 is disposed within the travel track R.

[0030] The traveling unit 2 has a front traveling body 2A and a rear traveling body 2B. A connecting part 2D provided on the front traveling body 2A and a connecting part 2D provided on the rear traveling body 2B are rotatably connected via a connecting shaft 2E. Each of the front traveling body 2A and the rear traveling body 2B is provided with traveling rollers 2C and 2C, and traveling drive units 2M and 2M. In this embodiment, the traveling drive unit 2M is an LDM (Linear DC Motor) that accelerates or brakes the aerial transport vehicle 1 using magnetic force generated between itself and a magnetic plate P disposed on the upper surface of the traveling track R.

[0031] The main body 3 is suspended and supported on the running gear 2. More specifically, a pair of suspension members 2F, 2F extending vertically downward from the running gear 2 are connected to the vibration damping unit 20 provided on the main frame 4 of the main body 3, thereby suspending and supporting the main body 3 on the running gear 2. It should be noted that the vibration damping unit 20 will be described in detail below. The main body 3 includes a main frame 4, a horizontal drive unit 5, a rotary drive unit 6, a lifting drive unit 7, a lifting unit 10, a pair of covers 8, 8, and a controller 80.

[0032] The horizontal drive unit 5 is fixed to the lower part of the main frame 4. The horizontal drive unit 5 moves the rotary drive unit 6, the lifting drive unit 7, and the lifting unit 10 in the horizontal plane in a direction orthogonal to the extension direction of the travel track R (left-right direction). The rotary drive unit 6 rotates the lifting drive unit 7 and the lifting unit 10 in the horizontal plane. The lifting drive unit 7 raises and lowers the lifting unit 10 by winding and unwinding the four belts 9. It should be noted that the belts 9 in the lifting drive unit 7 can also use suitable lifting components such as wires and ropes.

[0033] The lifting unit 10 is configured to be raised and lowered by the lifting drive unit 7, functioning as a lifting platform in the aerial transport vehicle 1. The lifting unit 10 has a holding device 11 for holding the transported item 90, and is raised and lowered relative to the horizontal drive unit 5, the rotary drive unit 6, and the lifting drive unit 7, which are the main body, by the belt 9. The holding device 11 holds the transported item 90. The holding device 11 includes a pair of arms 12, 12 formed in an L-shape, claws 13, 13 fixed to each arm 12, 12, and an opening and closing mechanism 15 for opening and closing the pair of arms 12, 12.

[0034] The opening and closing mechanism 15 moves a pair of arms 12, 12 in the direction of approaching each other and in the direction of separation. The pair of arms 12, 12 move forward and backward in the back-and-forth direction by the action of the opening and closing mechanism 15. As a result, a pair of claws 13, 13 fixed to the arms 12, 12 open and close.

[0035] In this embodiment, when the pair of claws 13, 13 are in the open state, the height position (lowering) of the holding device 11 (lifting part 10) is adjusted so that the holding surface of the claws 13 is below the lower surface of the flange 98. Furthermore, by closing the pair of claws 13, 13 in this state, the holding surfaces of the claws 13, 13 are positioned below the lower surface of the flange 98. In this state, the lifting part 10 is raised, thereby holding (gripping) the flange 98 by the pair of claws 13, 13, thus supporting the object 90 being transported.

[0036] A pair of covers 8, 8 are arranged at the front and rear of the vehicle in the travel direction, covering the horizontal drive unit 5, the rotary drive unit 6, the lifting drive unit 7, the lifting unit 10, and the holding device 11. When the lifting unit 10 is raised to its raised end, the pair of covers 8, 8 form a space below the holding device 11 to accommodate the transported item 90. Each of the pairs of covers 8, 8 has a fall prevention mechanism 8A and a swing suppression mechanism 8B. When the lifting unit 10 is raised to its raised end, the fall prevention mechanism 8A prevents the transported item 90 held by the holding device 11 from falling. The swing suppression mechanism 8B suppresses the swing of the transported item 90 held by the holding device 11 in the front-rear direction (travel direction) and the left-right direction of the aerial transport vehicle 1 during travel.

[0037] The controller 80 is an electronic control unit composed of a CPU (Central Processing Unit), ROM (Read Only Memory), and RAM (Random Access Memory). The controller 80 controls various actions within the aerial transport vehicle 1. Specifically, the controller 80 controls the traveling unit 2, the horizontal drive unit 5, the rotary drive unit 6, and the lifting drive unit 7. The controller 80 can be configured as software that loads, for example, a program stored in ROM onto RAM and is executed by the CPU. The controller 80 can also be configured as hardware based on electronic circuits. The controller 80 communicates with a higher-level controller (not shown) using a power supply unit (power line) or feeder line of the traveling track R.

[0038] Explanation of vibration damping unit 20. For example... Figures 3-5 As shown, the vibration damping unit 20 includes a pair of support parts 21, 21, a base part 23, and a pair of shock absorbers 30, 30.

[0039] A pair of support portions 21, 21 are spaced apart in the left-right direction and fixed to the upper surface 4a of the main frame 4. The pair of support portions 21, 21 are fixed to the main frame 4, for example, by screws 22 or other components. A rotating shaft 26 extending horizontally in the left-right direction is mounted on the pair of support portions 21, 21. More specifically, each of the pair of support portions 21, 21 has an insertion hole 21a for the rotating shaft 26 to pass through. A cylindrical resin bushing 27 is inserted into the insertion hole 21a, and the rotating shaft 26 is inserted into the resin bushing 27. That is, the rotating shaft 26 is supported by the pair of support portions 21, 21 by means of the resin bushing 27. The rotating shaft 26 is positioned approximately at the center of the main frame 4 in the front-rear direction, but may also be offset forward or backward corresponding to the center of gravity of the main frame 4.

[0040] The base portion 23 is suspended from the running gear 2 by means of a pair of suspension members 2F, 2F. The base portion 23 is a member that extends in the front-rear direction. Through holes 23a, 23a are formed on the base portion 23 for the pair of suspension members 2F, 2F to pass through. Through holes 23a, 23a are formed at both ends of the base portion 23 in the front-rear direction. In addition, a bearing 23b is provided on the inner peripheral surface of the through hole 23a to support the suspension member 2F rotatably about an axis along the extension direction of the suspension member 2F.

[0041] The base portion 23 is configured in a manner that prevents it from rotating relative to the rotation shaft 26. More specifically, the rotation shaft 26 is inserted into a through hole 23c formed in the base portion 23, and the rotation shaft 26 is fixed to the base portion 23 by screws 24A. The base portion 23 is supported in a rotatable state by means of the horizontally extending rotation shaft 26 on a pair of support portions 21, 21. In other words, the pair of support portions 21, 21 rotatably support the rotation shaft 26, which rotates integrally with the base portion 23.

[0042] A pair of shock absorbers 30, 30 are arranged to sandwich the rotating shaft 26 in the front-rear direction and are configured to contact the upper surface 4a of the main frame 4. Furthermore, the shock absorbers 30 are inserted into through holes 23d formed in the base portion 23, and are positioned such that a portion protrudes downwards (towards the upper surface 4a of the main frame 4). The shock absorbers 30 absorb the energy generated when in contact with the upper surface 4a of the main frame 4.

[0043] like Figure 5 and Figure 6As shown, the shock absorber 30 includes a rubber component 31, a spring component 32, a contact portion 33, a receiving portion 34, and a buffer portion 35. The rubber component 31 has elastic force and is formed of a material such as polyurethane rubber. The spring component 32 is arranged to be inserted into the rubber component 31. The elastic force of the spring component 32 can also be greater than the elastic force of the rubber component 31. Thus, if the spring component 32 contracts to a certain extent, the elastic force of the rubber component 31 is added to the contact portion 33. The contact portion 33 is a component that contacts the upper surface 4a of the main frame 4. The lower part of the contact portion 33 that contacts the upper surface 4a of the main frame 4 is formed of a compression-resistant material such as ultra-high molecular weight polyethylene. A flange portion 33a is formed on the upper part of the contact portion 33 to contact the lower ends of the rubber component 31 and the lower ends of the spring component 32. In this embodiment, the spring component 32 is in contact with the contact portion 33 in a compressed state, i.e., a pressurized state. The receiving portion 34 houses the rubber component 31, the spring component 32, and a portion of the contact portion 33. The buffer portion 35 is a resin bushing provided to prevent wear caused by the up-and-down movement of the contact portion 33.

[0044] A cover 28 is provided on the base portion 23, covering the upper opening of the through hole 23d. The cover 28 is fixed to the base portion 23 by screws 28A or the like. An adjusting screw 29 is provided in the center of the cover 28 to adjust the amount of pressure of the shock absorber 30 against the main frame 4 (the amount of protrusion of the contact portion 33 from the base portion 23). The tip of the adjusting screw 29 abuts against the upper surface 34a of the receiving portion 34. The amount of protrusion of the contact portion 33, which protrudes from the lower surface of the base portion 23, can be adjusted by rotating the adjusting screw 29 of the cover 28.

[0045] Explain the effects of the aerial transport vehicle 1 in the above-described embodiment. For example... Figure 4 As shown, in the aerial transport vehicle 1 of the above embodiment, vibrations propagating from the traveling section 2 are absorbed by the base section 23, which is rotatably supported on the main body section 3 (main body frame 4). Furthermore, in the aerial transport vehicle 1 of the above embodiment, even if the traveling section 2 tilts due to climbing over different levels during travel, the main body section 3, whose weight is relatively large compared to the traveling section 2, attempts to maintain its posture due to inertial forces. Additionally, in the aerial transport vehicle 1 of the above embodiment, the relative positional relationship between the main body section 3 and the traveling section 2 is stably maintained by the shock absorber 30. As a result, the propagation of vibrations from the traveling section 2 to the transported object 90 can be suppressed, and the swaying of the transported object 90 can be prevented.

[0046] In the aerial transport vehicle 1 of the above-described embodiment, such as Figure 5As shown, the rotating shaft 26 is arranged to extend in the left-right direction and is positioned at the center of the main body 3 in the travel direction of the traveling section 2. A pair of shock absorbers 30, 30 are provided to clamp the rotating shaft 26 in the travel direction of the traveling section 2. Therefore, when the angle of the traveling section 2 is allowed to change relative to the main body 3, since the angle change is only allowed in the travel direction of the traveling section 2, the tilt of the main body 3 can be kept to a minimum when the transported object 90 is transferred in the left-right (lateral) direction.

[0047] In the aerial transport vehicle 1 of the above embodiment, the suspension members 2F, 2F are rotatably supported on the base portion 23 by means of the bearing 23b about the extending direction of the suspension members 2F, 2F. Therefore, torsional stress generated between the mounting portion of the suspension members 2F toward the traveling part 2 and the mounting portion of the suspension members 2F toward the base portion 23 can be suppressed.

[0048] In the aerial transport vehicle 1 of the above embodiment, since the pair of shock absorbers 30, 30 that are in direct contact with the main body 3 and the pair of suspension components 2F, 2F that are connected to the traveling unit 2 are configured so that they do not overlap when viewed from above, it is possible to suppress the direct lifting of the traveling unit 2 by changes in the attitude of the main body 3. As a result, the possibility of collision between the LDM constituting the traveling drive unit 2M and the magnetic plate P can be reduced.

[0049] In the aerial transport vehicle 1 of the above-described embodiment, such as Figure 6 As shown, the shock absorber 30 has a rubber component 31 and a spring component 32, therefore, the pressure generated by the shock absorber 30 can be easily adjusted by compressing the spring component 32. The shock absorber 30 of this embodiment applies a predetermined pressure. Furthermore, in the aerial transport vehicle 1 of this embodiment, as... Figure 7 As shown in (A), when neither the running gear 2 nor the main body 3 is tilted, the contact portion 33 of the shock absorber 30 contacts the upper surface 4a of the main body frame 4 in a state where the contact portion 33 does not exert any force on the main body frame 4. It should be noted that the protrusion of the contact portion 33 is adjusted by rotating the adjusting screw 29, thereby enabling the contact portion 33 to contact the upper surface 4a of the main body frame 4.

[0050] Here, when the driving unit 2 accelerates forward, such as Figure 7As shown in (B), the base portion 23, in its freely rotating state, experiences a force that causes it to sink forward. However, in the pressurized shock absorber 30, even with this force causing the base portion 23 to sink forward, the spring member 32 and rubber member 31 will not be compressed until a force exceeding a certain limit (i.e., a force exceeding the force applied to the spring member 32 as pressurization) is applied, and the base portion 23 will not tilt relative to the main frame 4. In the shock absorber 30 of the above embodiment, it is configured to withstand the force generated by the assumed acceleration. With this configuration, the attitude of the main frame 4 can be suppressed from changing during the acceleration of the air transport vehicle 1. That is, the swaying of the transported object 90 can be suppressed during the acceleration of the air transport vehicle 1.

[0051] In the aerial transport vehicle 1 of this embodiment, since the shock absorbers 30, 30 in both the front and rear directions are pressurized as described above, therefore, although there is no Figure 7 As shown in diagram (B), the posture of the main frame 4 can be suppressed even when the aerial transport vehicle 1 decelerates. That is, in this embodiment, since it is designed to withstand the pressure generated by the assumed deceleration, the swaying of the transported object 90 during the deceleration of the aerial transport vehicle 1 can be suppressed.

[0052] The above description describes one embodiment, but one aspect of the present invention is not limited to the above embodiment. Various modifications can be made without departing from the spirit of the invention.

[0053] In the aerial transport vehicle 1 of the above embodiment, a pair of support parts 21, 21 support the rotating shaft 26 rotatably by means of resin bushing 27. If the resin bushing 27 is replaced with a rubber bushing made of, for example, nitrile rubber, the torsion of the rubber bushing can not only effectively suppress the propagation of vibration in the rotation direction of the rotating shaft 26, but also effectively suppress the propagation of vibration from other directions, such as vibration from the traveling part 2, to the transported object 90.

[0054] In the above embodiment, an example was described in which the base portion 23 is configured to rotate only in the front-back direction (with the axis extending in the left-right direction as the axis of rotation), but it can also be configured such that the base portion 23 can rotate only in the left-right direction (with the axis extending in the front-back direction as the axis of rotation).

[0055] In the above embodiments and variations, an example was given in which the traveling unit 2 has a front traveling body 2A and a rear traveling body 2B that can rotate with each other, but it can also be formed by a single traveling body.

[0056] In the above embodiments and variations, an example was described where the rotating shaft 26 is supported by a pair of support portions 21, 21 by means of resin bushings 27. Furthermore, the resin bushings 27, 27, inserted into the insertion holes 21a of each of the pair of support portions 21, 21, can also be made of materials with different hardness. For example, by making the left and right resin bushings 27, 27 different from each other, when the center of gravity of the vibration damping unit 20 is different from the center of gravity of the main body 3 when viewed from the Z-axis direction, it is easy to maintain the relative positional relationship (or attitude of the main body 3 relative to the traveler 2) of the main body 3 relative to the traveler 2 when the object to be transported 90 is moved in the left-right (lateral) direction.

[0057] Explanation of reference numerals in the attached figures

[0058] 1…Aerial transport vehicle, 2…Driving section, 2F…Suspension component, 3…Main body, 4…Main frame, 4a…Upper surface, 20…Vibration damping unit, 21…Support section, 23…Base section, 23a…Intercepting hole, 23b…Bearing, 23c…Intercepting hole, 23d…Intercepting hole, 24A…Screw, 26…Rotating shaft, 27…Resin bushing, 28…Cover, 28A…Screw, 29…Adjusting screw, 30…Shock absorber, 31…Rubber component, 32…Spring component, 33…Contact part, 34…Receiving part.

Claims

1. An aerial transport vehicle that suspends and supports the main body of the object being transported on a traveling unit, the aerial transport vehicle being characterized by comprising: The base portion is suspended from the traveling portion; A support portion is provided on the main body portion and rotatably supports the base portion by means of a rotating shaft extending in the horizontal direction; as well as A pair of shock absorbers are disposed on the base portion in a manner that clamps the rotation axis in a second direction orthogonal to both the first direction extending from the rotation axis and the vertical direction, and are configured to contact the main body portion. The shock absorber has a rubber component, a spring component, and a contact portion. The spring component is configured to be inserted into the rubber component. The upper flange of the contact portion contacts the lower ends of the rubber component and the spring component, and the lower portion of the contact portion contacts the upper surface of the main body frame of the main body. When neither the traveling section nor the main body is tilted, the contact section contacts the upper surface of the main frame in a state where the contact section does not exert any force on the main body. The spring component is in a compressed state and contacts the contact portion, thereby applying a specified pressure to the shock absorber.

2. The aerial transport vehicle according to claim 1, characterized in that, The rotating shaft is arranged to extend in a direction orthogonal to both the travel direction and the vertical direction of the traveling unit, and is positioned at the center of the main body in the travel direction of the traveling unit. The pair of shock absorbers are arranged such that they sandwich the rotating shaft in the direction of travel of the vehicle.

3. The aerial transport vehicle according to claim 2, characterized in that, The base portion is suspended from the travel portion by a pair of suspension members extending downward in a vertical direction. The base portion is capable of supporting the suspension component to rotate about an axis with the extension direction of the suspension component as the axis of rotation.

4. The aerial transport vehicle according to claim 3, characterized in that, The traveling unit has a traveling drive unit that accelerates or brakes the traveling unit by means of magnetic force generated between the traveling unit and a magnetic plate disposed on the traveling track. When viewed from above in a vertical direction, the pair of suspension components and the pair of shock absorbers are configured not to overlap.

5. The aerial transport vehicle according to any one of claims 1 to 4, characterized in that, The support portion rotatably supports the rotating shaft with the aid of a rubber bushing.

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