Goods transport vehicle

Abstract

To realize an article carrying vehicle capable of appropriately placing an article in a loading place by preventing the article from tilting with respect to an appropriate posture, while making it possible to suppress vibrations transmitted to the article to a small degree.SOLUTION: An article carrying vehicle comprising a travelling body, a holding device 23 for holding an article 6, and an elevating / lowering device for elevating / lowering the holding device 23 with respect to the travelling body, that is installed in the travelling body is an article carrying vehicle whose holding device 23 comprises a connection part 31 connected to the elevating / lowering device, and an article support part 51 for supporting the article 6. The holding device 23 comprises an elastic support mechanism 36 for supporting the article support part 51 with respect to the connection part 31 in a state of exhibiting elasticity in an upward-downward direction Z, that is provided between the article support part 51 and the connection part 31; and a guide mechanism 37 for guiding movement in the upward-downward direction Z of the article support part 51 with respect to the connection part 31. The guide mechanism 37 allows parallel translation in the upward-downward direction Z of the article support part 51 with respect to the connection part 31, and regulates oscillation of the article support part 51 with respect to the connection part 31.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an article transport vehicle that includes a running body that runs along a travel path, a holding device that holds articles, and a lifting device mounted on the running body that raises and lowers the holding device relative to the running body. [Background technology]

[0002] A conventional article transport vehicle of this type is disclosed in JP 2016-094263 A (Patent Document 1). In the following description of the background art, the reference numerals in parentheses refer to those in Patent Document 1.

[0003] The article transport vehicle (1) disclosed in Patent Document 1 includes a traveling section (16) that travels along a travel path on a traveling rail (2), a support mechanism (23) that is supported by the traveling section (16) and that suspends and supports an article (transported object 6), and a lifting support section (17) that supports the support mechanism (23) so that it can move up and down. The support mechanism (23) includes a lifting body (31), a guide support section (35), and a buffer body (36) that is elastically deformable in the vertical direction and is located between the lifting body (31) and the guide support section (35) to receive the load of the guide support section (35). This makes it possible to reduce vibrations transmitted to the article (6) when the traveling section (16) travels and when the lifting body (31) moves up and down. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2016-094263 A Summary of the Invention [Problem to be solved by the invention]

[0005] The article transport vehicle (1) disclosed in Patent Document 1 rotates and drives the reel (28) and unwinds the take-up belt (24a) to transfer an article (6) to a support stand (4) on the floor surface, thereby lowering the support mechanism (23) together with the article (6). Generally, the support stand (4) is provided with a positioning mechanism such as a positioning pin for positioning the article (6), so in order to properly transfer the article (6) to the support stand (4), it is necessary to lower the article (6) to the support stand (4) in a proper posture.

[0006] However, in the article transport vehicle (1) disclosed in Patent Document 1, since the guide support part (35) is supported on the lifting body (31) via the buffer body (36), when an uneven load acts on the guide support part (35), the guide support part (35) may tilt with respect to the lifting body (31). For example, when the center of gravity of the article (6) is unevenly positioned, the amount of deformation of the buffer body (36) may be uneven, causing the guide support part (35) to tilt with respect to the lifting body (31), and the article (6) may assume an inclined position with respect to the proper position. In this way, when the article (6) descends to the support platform (4) in an inclined position with respect to the proper position, the article (6) may not be properly transferred to the support platform (4). On the other hand, if the elastic modulus of the buffer body (36) is increased in order to prevent the article (6) from assuming an inclined position, it becomes difficult to properly suppress the vibration transmitted to the article (6).

[0007] Therefore, it is desirable to realize an article transport vehicle that can minimize vibrations transmitted to articles while preventing the articles from tilting relative to the correct posture, thereby allowing the articles to be placed appropriately in the placement location. [Means for solving the problem]

[0008] In view of the above, a characteristic configuration of an article transport vehicle includes a running body that runs along a running path, a holding device that holds an article, and a lifting device that is mounted on the running body and raises and lowers the holding device relative to the running body, the holding device having a connecting portion connected to the lifting device, an article support portion that contacts the article and supports the article, A gripping and guiding mechanism;an article transport vehicle comprising: the holding device comprising: an elastic support mechanism provided between the article support part and the connecting part for supporting the article support part in a state in which the article support part is elastically supported in the vertical direction relative to the connecting part; and a guide mechanism for guiding the vertical movement of the article support part relative to the connecting part, the guide mechanism being configured to permit parallel movement of the article support part relative to the connecting part in the vertical direction and to restrict swinging of the article support part relative to the connecting part. The article support section includes a pair of gripping sections, the direction in which the pair of gripping sections are aligned is defined as an alignment direction, the pair of gripping sections are arranged at a distance from each other in the alignment direction, and are configured to move toward and away from each other along the alignment direction, the guide mechanism includes a first guide mechanism and a second guide mechanism arranged at a distance from each other in the alignment direction to correspond to the pair of gripping sections, the gripping guide mechanism is supported by the connecting section and is configured to guide movement of the pair of gripping sections in the alignment direction, one of the pair of gripping sections is a first gripping section and the other of the pair of gripping sections is a second gripping section, the elastic support mechanism includes a first elastic support mechanism corresponding to the first gripping section and a second elastic support mechanism corresponding to the second gripping section, the first gripping section is supported by the gripping guide mechanism via the first guide mechanism and the first elastic support mechanism, and the second gripping section is supported by the gripping guide mechanism via the second guide mechanism and the second elastic support mechanism. The point is that...

[0009] According to this configuration, since an elastic support mechanism is provided between the article support part and the connecting part, the elastic support mechanism can attenuate vibrations of the running body caused by the running of the running body, vibrations of the holding device caused by the lifting device being raised and lowered, etc. Therefore, the vibrations transmitted to the articles can be reduced. In addition, according to this configuration, since the guide mechanism is configured to restrict the swinging of the article support part relative to the connecting part, it is possible to restrict the article support part from tilting relative to the connecting part. Therefore, even if an uneven load acts on the article support part due to, for example, an uneven center of gravity of the article, it is possible to restrict the article support part and the article supported by the article support part from tilting relative to the connecting part. Therefore, when the holding device is lowered by the lifting device to place the article on the placement location, it is possible to avoid a situation in which the article cannot be placed properly because the posture of the article is tilted from the correct posture. Meanwhile, the guide mechanism allows the article support part to move in parallel in the vertical direction relative to the connecting part. Therefore, the effect of the elastic support mechanism to reduce the vertical vibration acting on the article support part and the article supported by the article support part is not hindered by the guide mechanism. Thus, with this configuration, it is possible to minimize vibrations transmitted to the article, while preventing the article from tilting relative to the correct posture, thereby enabling the article to be properly placed on the placement location.

[0010] Further, in view of the above, a characteristic configuration of another article transport vehicle is an article transport vehicle comprising a running body that runs along a running path, a holding device that holds an article, and a lifting device that is mounted on the running body and raises and lowers the holding device relative to the running body, wherein the holding device comprises a connecting portion connected to the lifting device, an article support portion that contacts the article to support the article, and a gripping guide mechanism, wherein the holding device comprises: an elastic support mechanism that is provided between the article support portion and the connecting portion and supports the article support portion in a state in which the article support portion has elasticity in the vertical direction relative to the connecting portion; and a guide mechanism that guides the vertical movement of the article support portion relative to the connecting portion, wherein the guide mechanism is configured to allow parallel movement of the article support portion in the vertical direction relative to the connecting portion and to restrict swinging of the article support portion relative to the connecting portion, and the article support portion comprises a pair of the direction in which the pair of gripping parts are lined up is defined as an arrangement direction, the pair of gripping parts are arranged at a distance from each other in the arrangement direction, the guide mechanism is configured to guide the up-down movement of each of the pair of gripping parts relative to the connecting part, the guide mechanism includes a first guide mechanism and a second guide mechanism arranged at a distance from each other in the arrangement direction to correspond to the pair of gripping parts, one of the pair of gripping parts is a first gripping part and the other of the pair of gripping parts is a second gripping part, a placement area of ​​the first guide mechanism in the arrangement direction overlaps with a placement area of ​​a portion of the first gripping part below the connecting part in the arrangement direction, and a placement area of ​​the second guide mechanism in the arrangement direction overlaps with a placement area of ​​a portion of the second gripping part below the connecting part in the arrangement direction. [Brief description of the drawings]

[0011] [Figure 1] Side view of the goods transport facility [Diagram 2] Side view of overhead transport vehicle [Diagram 3] FIG. 1 is a vertical sectional side view of a holding device in which a pair of transported object support parts are positioned at a supporting position; [Figure 4] Plan view of the holding device [Diagram 5] 1 is a side view of an article transport vehicle in a traveling state in which an article support unit is tilted in the traveling direction; [Figure 6] A side view of the item being properly placed on the placement site. [Figure 7] A side view of an article being transferred to a placement location in an inclined state. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] 1. Embodiment DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which an article transport vehicle according to the present invention is applied to an article transport facility will be described below with reference to the drawings. As shown in FIG. 1, the article transport facility includes an article transport vehicle 1 configured as a ceiling transport vehicle capable of traveling along a traveling rail 2 arranged on the ceiling side, a processing device 3 for processing a substrate housed in an article 6, and a placement location 4 such as a support table installed on the floor surface adjacent to the processing device 3. Here, the support table is an example of the placement location 4 for the article 6 by the article transport vehicle 1. Thus, in this embodiment, the travel path of the article transport vehicle 1 is configured by the traveling rail 2. The article 6 transported by the article transport vehicle 1 is a transport container that contains an item, specifically, a FOUP (Front Opening Unify Pod) that contains a plurality of semiconductor substrates as the item.

[0013] The placement locations 4, such as support platforms on which the articles 6 are placed, are installed below the travel path of the article transport vehicle 1, and a plurality of placement locations 4 are installed along the travel direction X of the article transport vehicle 1. The article transport vehicle 1 transports the articles 6 and lowers the articles 6 using the lifting device 24 to place the articles 6 on the placement locations 4. The article transport vehicle 1 also receives the articles 6 from the placement locations 4, lifts them using the lifting device 24, and transports the articles 6 to another destination. In this embodiment, the delivery of the articles 6 between the article transport vehicle 1 and the placement locations 4 is referred to as transfer, and such an operation is referred to as a transfer operation. In this embodiment, the placement surface 4a on which the articles 6 are placed at the placement locations 4 is provided with an engagement protrusion P for positioning the articles 6. In this example, three engagement protrusions P are arranged on the placement surface 4a in such a positional relationship that they are located at the apexes of a triangle. In this example, after a FOUP as an article 6 is placed on a support table as a placement location 4, a semiconductor substrate is removed from the FOUP by a processing device 3 and subjected to a predetermined processing. Then, the FOUP containing the semiconductor substrate after the processing is completed is received by the article transport vehicle 1 and transported to a destination such as another processing device 3.

[0014] [Goods] As shown in FIG. 2, an article 6 according to this embodiment includes a main body portion 7 that houses a plurality of substrates, and a flange portion 9 provided on an upper portion of the article 6 above the main body portion 7. The article 6 also includes a lid 5 (see FIG. 6) that closes an opening for inserting and removing a substrate, which is formed on the front surface of the main body 7. The lid 5 is provided so as to be freely attached and detached to the main body 7. In the following description, when viewed in the up-down direction along the up-down direction Z, the direction perpendicular to the lid 5 from the center of the article 6 is defined as the front-rear direction of the article, and the direction perpendicular to the front-rear direction of the article is defined as the left-right direction of the article.

[0015] In this embodiment, the weight per unit volume of the lid 5 is larger than that of the other parts of the article 6 (FOUP). Therefore, when the main body 7 is empty and does not contain a semiconductor substrate, the center of gravity of the article 6 is biased toward the lid 5 side in the front-rear direction of the article. When the main body 7 contains a semiconductor substrate and the overall weight of the article 6 increases, the proportion of the weight of the lid 5 in the weight decreases. Therefore, the position of the center of gravity moves toward the opposite side to the lid 5 side in the front-rear direction of the article so as to approach the center of the article 6. In addition, the article 6 is configured so that the weight is uniform in the left-right direction of the article. Therefore, even when the article 6 is empty or contains a semiconductor substrate, the center of gravity of the article 6 is not biased in the left-right direction of the article.

[0016] The flange portion 9 and the main body portion 7 are connected via an article connecting portion 8. The article connecting portion 8 is formed so as to protrude upward from the main body portion 7. The flange portion 9 is attached to an upper portion of the article connecting portion 8 and is formed in a plate shape protruding from the article connecting portion 8 in the article front-rear direction and the article left-right direction. An insertion space 12 is formed by recesses in the article front-rear direction and the article left-right direction formed between the upper surface of the main body portion 7 and the lower surface of the flange portion 9. A pair of gripping portions 50, which will be described later, is inserted into this insertion space 12, whereby the article 6 is gripped by the pair of gripping portions 50.

[0017] As shown in FIG. 6, the article 6 has an engagement recess B provided on the bottom 11. The engagement recess B is for positioning the article 6 at the placement location 4 by engaging with the engagement protrusion P provided on the placement surface 4a of the placement location 4. In this embodiment, three engagement recesses B are arranged in a positional relationship such that they are located at the apexes of a triangle on the bottom surface 11a, which is the downward surface of the bottom 11. The positional relationship of the three engagement recesses B corresponds to the positional relationship of the three engagement protrusions P of the placement location 4. Each engagement recess B is a recessed groove recessed upward from the bottom surface 11a. In this example, two of the three engagement recesses B are provided close to the front end of the article 6 and spaced apart in the left-right direction of the article. One of the three engagement recesses B is provided close to the rear end of the article 6 and in the middle between the two engagement recesses B in the left-right direction. In this embodiment, as shown in FIG. 6, when the item 6 is placed on the placement location 4 by being lowered by the lifting device 24 described later, the engagement recess B engages with a positioning engagement protrusion P provided on the placement location 4.

[0018] [Goods transport vehicle] Next, the article transport vehicle 1 will be described. Here, the direction along the travel direction of the article transport vehicle 1 will be referred to as the travel direction X, and the direction perpendicular to the travel direction X when viewed from above and below will be referred to as the width direction Y. In this embodiment, the article 6 is supported with its left-right direction oriented along the travel direction X of the article transport vehicle 1. Therefore, in the following description, the left-right direction of the article 6 will be referred to as the travel direction X, and the front-rear direction of the article 6 will be referred to as the width direction Y, based on the state in which the article 6 is held by the holding device 23.

[0019] 1 and 2, the article transport vehicle 1 includes a running body 16 that travels along a travel path, a holding device 23 that holds an article 6, and a lifting device 24 that is mounted on the running body 16 and raises and lowers the holding device 23 relative to the running body 16. The article transport vehicle 1 further includes a cover portion 25 that covers the upper side of the article 6 supported by the holding device 23 and both sides in the traveling direction X when the holding device 23 is positioned near the upper limit of the lifting range of the lifting device 24.

[0020] 2, the running body 16 includes a drive wheel 20 that is rotationally driven by a traveling motor 19 and rolls on the upper surface of the running rail 2, and a rotatable guide wheel 21 that abuts against the side surface of the running rail 2. The drive wheel 20 is rotationally driven by the traveling motor 19, and the guide wheel 21 abuts against and is guided by the side surface of the running rail 2. As a result, the running body 16 is guided by the running rail 2 and runs along the travel route.

[0021] The lifting device 24 includes a winding body 28 that winds the winding belt 24a, and a lifting motor 29 that rotates the winding body 28. The holding device 23 is connected to the tip of the winding belt 24a. The lifting device 24 lifts and lowers the holding device 23 relative to the traveling body 16 by using the lifting motor 29 to rotate the winding body 28 in the forward direction to pay out the winding belt 24a and to rotate the winding body 28 in the reverse direction to take up the winding belt 24a.

[0022] [Holding device] Next, the holding device 23 of the article transport vehicle 1 will be described. As shown in Figs. 3 to 5, the holding device 23 of the article transport vehicle 1 includes a connecting portion 31 connected to the lifting device 24, and an article support portion 51 that contacts the article 6 and supports the article 6. In this embodiment, the connecting portion 31 is connected to the tip of the winding belt 24a. Therefore, the connecting portion 31 is raised and lowered by the lifting device 24. The connecting portion 31 includes a support body 31a that supports an elastic support mechanism 36 and a guide mechanism 37, which will be described later, and a box-shaped housing 31b that is attached to the support body 31a and covers the elastic support mechanism 36 and the guide mechanism 37. In this embodiment, the holding device 23 includes a gripping drive mechanism 30 that drives a pair of gripping portions 50 that constitute the article support portion 51 in a direction that moves them closer to and away from each other. This gripping drive mechanism 30 is also supported by the support body 31a and is housed inside the housing 31b.

[0023] First, a description will be given of the grip drive mechanism 30. The grip drive mechanism 30 includes a grip guide mechanism 38, a grip drive source 33, and a grip transmission mechanism 39. In this embodiment, the grip drive source 33 is a grip drive motor constituted by an electric motor.

[0024] The gripping guide mechanism 38 is a mechanism for guiding the movement of the pair of gripping parts 50 in the direction toward and away from each other. In this embodiment, the direction toward and away from the pair of gripping parts 50 is parallel to the traveling direction X. In this example, the gripping guide mechanism 38 is provided corresponding to each of the pair of gripping parts 50, and includes an interlocking member 42 interlocked with the movement of each of the pair of gripping parts 50 in the direction toward and away from each other, and a guide rail 40 for guiding the movement of the pair of interlocking members 42 in the direction toward and away from each other. Here, as shown in FIG. 4, a plurality of guide rails 40 are supported by the support body 31a so as to be aligned along the traveling direction X. In this embodiment, a pair of guide rails 40 is arranged for one interlocking member 42 at a distance in the width direction Y. Therefore, in this embodiment, the gripping guide mechanism 38 includes four guide rails 40 corresponding to the pair of interlocking members 42. 3 and 4, a guided member 41 that is guided in the running direction X along the guide rail 40 is attached to each of the interlocking members 42 at a portion that is guided by each guide rail 40. The guided member 41 is engaged with the guide rail 40 in a state that is freely movable along the guide rail 40.

[0025] As described above, the interlocking members 42 are provided corresponding to each of the pair of gripping portions 50. Each interlocking member 42 is configured to connect the grip transmission mechanism 39 and the guide mechanism 37. The interlocking members 42 and the gripping portions 50 are connected via the guide mechanism 37. In this embodiment, as described later, the guide mechanisms 37 corresponding to each of the pair of gripping portions 50 each include a pair of linear guide mechanisms 37a. Therefore, the interlocking members 42 connect the grip transmission mechanism 39 and the pair of linear guide mechanisms 37a.

[0026] Specifically, the interlocking member 42 includes a pair of interlocking fixing parts 42a fixed to each of a pair of linear guide mechanisms 37a supporting the same gripping part 50, an interlocking main body part 42b connecting the pair of interlocking fixing parts 42a to each other, and an interlocking connection part 42c provided on the interlocking main body part 42b and connected to the grip transmission mechanism 39. In this example, the interlocking main body part 42b is formed in a long plate shape that is long in the width direction Y. The interlocking main body part 42b is fixed to two guided members 41 arranged at a distance in the width direction Y. The interlocking main body part 42b is also connected to a pair of interlocking fixing parts 42a arranged at a distance in the width direction Y. In this example, each of the pair of interlocking fixing parts 42a is arranged so as to overlap with the guided member 41 when viewed in the up-down direction Z. In this way, the interlocking main body part 42b connects the pair of guided members 41 to each other and also connects the pair of interlocking fixing parts 42a to each other. The pair of interlocking fixing parts 42a are formed to have a larger dimension in the vertical direction Z than the interlocking main body part 42b. The linear guide mechanism 37a is attached to a surface of each of the pair of interlocking fixing parts 42a that faces a direction perpendicular to the vertical direction Z. The interlocking connection part 42c is a part that is connected to the grip transmission mechanism 39 described later. In this embodiment, the nut part 35 that constitutes the grip transmission mechanism 39 is attached to the interlocking connection part 42c. Here, the interlocking connection part 42c is provided in the center part in the width direction Y of the interlocking main body part 42b. In the illustrated example, the interlocking connection part 42c is formed in a block shape that holds the nut part 35 therein. In this embodiment, the interlocking connection parts 42c provided on each of the pair of interlocking members 42 are arranged apart from each other in the running direction X.

[0027] The grip transmission mechanism 39 is a mechanism that transmits the power of the grip drive source 33 to each of the pair of gripping parts 50, and moves the pair of gripping parts 50 in directions to move them closer to and away from each other. In this embodiment, the grip transmission mechanism 39 includes a ball screw 34 and a nut part 35 that screws into the ball screw 34.

[0028] The ball screw 34 is connected to a gripping drive motor serving as the gripping drive source 33. The ball screw 34 is driven by the gripping drive source 33 to rotate about its axis. In this embodiment, as shown in FIG. 4, the ball screw 34 is disposed so that its axis is aligned with the running direction X. In this example, the ball screw 34 is disposed in the center of the support 31a in the width direction Y. A male thread is formed on the outer circumferential surface of the ball screw 34. In this example, the male screw is formed so that the spiral direction is opposite on one side and the other side with respect to the center in the direction along the axis of the ball screw 34 (traveling direction X). Also, one end of the ball screw 34 on the side in the direction along the axis of the ball screw 34 (traveling direction X) is connected to the grip drive source 33. Specifically, one end of the ball screw 34 in the axial direction is connected to the output shaft of a grip drive motor.

[0029] The nut portion 35 is a cylindrical member having a female thread formed on its inner circumferential surface so as to be screwed into a male thread formed on the outer circumferential surface of the ball screw 34. Therefore, the axial direction of the nut portion 35 is also arranged along the running direction X, similar to the ball screw 34. In this embodiment, as described above, the nut portion 35 is attached to the interlocking connection portion 42c of the interlocking member 42. That is, the nut portion 35 is attached to each of a pair of interlocking connection portions 42c arranged at a distance from each other in the running direction X. Then, one nut portion 35 and the other nut portion 35 are screwed into portions of the ball screw 34 in which the male threads are oriented in different directions. Therefore, when the ball screw 34 rotates in a first direction, the pair of nut portions 35 approach each other, and when the ball screw 34 rotates in a second direction opposite to the first direction, the pair of nut portions 35 move away from each other. In conjunction with the approaching and separating movement of the pair of nut portions 35, the pair of interlocking members 42 and the pair of gripping portions 50 move toward and away from each other.

[0030] As shown in FIG. 4, the article support section 51 includes a pair of gripping sections 50, which are arranged apart from each other in the travel direction X. The article support section 51 is configured to grip a flange portion 9 of an article 6 with the pair of gripping sections 50. In this embodiment, each of the pair of gripping sections 50 is supported by the interlocking member 42 via an elastic support mechanism 36 and a guide mechanism 37, which will be described later. As shown in FIG. 3, each of the pair of gripping sections 50 includes a gripping claw portion 50a that is a portion that contacts the flange portion 9, a supported portion 50b that is supported by the elastic support mechanism 36 and the guide mechanism 37, and a gripping connecting portion 50c that connects the gripping claw portion 50a and the supported portion 50b. In this example, as shown in FIG. 6, the gripping claw portion 50a is formed in a long plate shape extending in the width direction Y. Also, as shown in FIG. 4 and FIG. 5, the supported portion 50b is formed to extend in the width direction Y. The gripping connecting parts 50c are provided at both ends of the gripping claw parts 50a and the supported parts 50b in the width direction Y, respectively, and connect the gripping claw parts 50a and the supported parts 50b. Thus, in this example, the gripping part 50 has a pair of gripping connecting parts 50c. The pair of gripping parts 50 have the same configuration as each other, except that they are oriented symmetrically.

[0031] The gripping claw portion 50a is disposed below the connecting portion 31. The supported portion 50b is accommodated inside the connecting portion 31. The gripping connecting portion 50c is disposed so as to protrude from inside the connecting portion 31 downward from the connecting portion 31 so as to connect the gripping claw portion 50a and the supported portion 50b. In this example, as shown in Figs. 3 and 4, the gripping connecting portion 50c extends in the up-down direction Z through a through hole 43 formed in the support body 31a of the connecting portion 31. As described above, each of the pair of gripping portions 50 includes a pair of gripping connecting portions 50c. Therefore, the support body 31a has four through holes 43 formed at intervals in the running direction X and the width direction Y, and one gripping connecting portion 50c is inserted into each through hole 43.

[0032] As shown in FIG. 3 and FIG. 6, the pair of gripping parts 50 grip the flange part 9 with the gripping claw parts 50a disposed in the insertion space 12 formed below the flange part 9. More specifically, the pair of gripping claw parts 50a abut against the flange part 9 from below, thereby supporting the flange part 9 from below. Here, as described above, each of the pair of gripping parts 50 is supported by the interlocking member 42 via the elastic support mechanism 36 and the guide mechanism 37 described later. Then, the pair of interlocking members 42 are driven by the grip driving mechanism 30 in the direction approaching and separating in the running direction X, so that the pair of gripping parts 50 are also driven in the direction approaching and separating. As a result, the interval between the pair of gripping parts 50 changes to a gripping interval and a release interval. The gripping interval is the interval when the pair of gripping parts 50 are close to each other. In this gripping interval state, the interval between the pair of gripping claw parts 50a in the running direction X becomes narrower than the width of the flange part 9 in the running direction X. The release interval is the interval when the pair of gripping portions 50 are separated from each other. In this release interval state, the interval between the pair of gripping claw portions 50a in the running direction X becomes wider than the width of the flange portion 9 in the running direction X.

[0033] Therefore, by changing the pair of gripping parts 50 from the release interval to the gripping interval, the flange portion 9 can be gripped and the article 6 can be held by the holding device 23. Also, by changing the pair of gripping parts 50 from the gripping interval to the release interval, the gripping of the flange portion 9 can be released and the holding of the article 6 by the holding device 23 can be released.

[0034] As shown in Figs. 3 to 5, the holding device 23 includes an elastic support mechanism 36 that is provided between the article support part 51 and the connecting part 31 and elastically supports the article support part 51 in the up-down direction Z relative to the connecting part 31. As described above, in this embodiment, the article support part 51 includes a pair of grip parts 50. Therefore, the elastic support mechanism 36 is configured to elastically support each of the pair of grip parts 50 relative to the connecting part 31. As described above, the pair of grip parts 50 are configured to be guided in the movement in the direction of approaching and separating from each other (here, the traveling direction X) by the grip guide mechanism 38. Therefore, each of the pair of grip parts 50 is supported by the interlocking member 42 that constitutes the grip guide mechanism 38 via the elastic support mechanism 36 and the guide mechanism 37. Therefore, in this embodiment, the elastic support mechanism 36 is configured to support the grip part 50 in an elastic state in the up-down direction Z relative to the interlocking member 42. More specifically, the elastic support mechanism 36 is provided between the interlocking body part 42b and the supported part 50b of the grip part 50 in the vertical direction Z. In the illustrated example, the supported part 50b is arranged above the interlocking body part 42b. Therefore, the elastic support mechanism 36 elastically supports the supported part 50b from below. In this example, the elastic support mechanism 36 includes an elastic body 36a having elasticity in the vertical direction Z. In the illustrated example, the elastic body 36a is a compression coil spring. The lower end of the elastic body 36a is held by the interlocking body part 42b, and the upper end of the elastic body 36a is held by the supported part 50b. That is, the interlocking body part 42b and the supported part 50b each include a holding part that holds the elastic body 36a. The elastic body 36a is arranged in a compressed state and sandwiched between the interlocking body part 42b and the supported part 50b.

[0035] In this embodiment, the elastic support mechanism 36 includes a pair of elastic bodies 36a arranged spaced apart in the width direction Y for each of the pair of gripping portions 50. As shown in Fig. 4, the pair of elastic bodies 36a corresponding to one gripping portion 50 are arranged spaced apart in the width direction Y. Also, in this embodiment, in each of the pair of gripping portions 50, the pair of elastic bodies 36a are arranged more inward in the width direction Y than the pair of guide rails 40.

[0036] Furthermore, in this embodiment, the elastic support mechanism 36 supports the pair of gripping parts 50 so that the pair of gripping parts 50 move up and down independently of each other. As described above, the elastic support mechanism 36 is provided corresponding to each of the pair of gripping parts 50, and is configured to elastically support each of the pair of gripping parts 50 with respect to the connecting part 31. Therefore, one of the pair of gripping parts 50 is supported by one of the pair of elastic support mechanisms 36 in a state in which it has elasticity in the up-down direction Z with respect to the connecting part 31, and the other of the pair of gripping parts 50 is supported by the other of the pair of elastic support mechanisms 36 in a state in which it has elasticity in the up-down direction Z with respect to the connecting part 31. As a result, the pair of gripping parts 50 are supported by the elastic support mechanism 36 so that they move up and down independently of each other.

[0037] As shown in FIG. 3 and FIG. 4, the holding device 23 includes a guide mechanism 37 that guides the movement of the article support part 51 in the up-down direction Z relative to the connecting part 31. The guide mechanism 37 is configured to allow the article support part 51 to move in parallel in the up-down direction Z relative to the connecting part 31, and to restrict the swinging of the article support part 51 relative to the connecting part 31. As described above, in this embodiment, the article support part 51 includes a pair of gripping parts 50. Therefore, the guide mechanism 37 is configured to allow each of the pair of gripping parts 50 to move in parallel in the up-down direction Z relative to the connecting part 31. In addition, the guide mechanism 37 is configured to restrict the swinging of each of the pair of gripping parts 50 in the width direction Y and the travel direction X relative to the connecting part 31. Therefore, in this embodiment, the guide mechanism 37 connects the gripping parts 50 and the interlocking member 42 in a state in which each of the pair of gripping parts 50 can move in parallel in the up-down direction Z relative to the corresponding interlocking member 42.

[0038] Here, the term "parallel movement" refers to the movement of the article support part 51 (in this embodiment, each of the pair of gripping parts 50) relative to the connecting part 31 while the first and second reference axes remain parallel, where the article support part 51 is not supporting the article 6 and the holding device 23 is in an ideal positional relationship with respect to the horizontal plane as a reference posture, a virtual axis serving as a reference for the connecting part 31 that is parallel to the vertical direction Z in the reference posture as a first reference axis, and a virtual axis serving as a reference for the article support part 51 that is parallel to the vertical direction Z in the reference posture as a second reference axis. In addition, the term "swing" refers to the movement of the article support part 51 (in this embodiment, each of the pair of gripping parts 50) relative to the connecting part 31 such that the second reference axis is tilted with respect to the first reference axis. The guide mechanism 37 is configured to restrict the swinging of the article support part 51 with respect to the connecting part 31, and therefore the article support part 51 is restricted from tilting with respect to the connecting part 31.

[0039] In this embodiment, as shown in FIG. 3 and FIG. 4, the guide mechanism 37 is configured to guide the movement of each of the pair of gripping parts 50 in the vertical direction Z relative to the connecting part 31. Here, the guide mechanism 37 is configured to guide the pair of gripping parts 50 so that the pair of gripping parts 50 move up and down independently of each other. For such guidance, the guide mechanism 37 includes a linear guide mechanism 37a. In this embodiment, the guide mechanism 37 includes linear guide mechanisms 37a arranged at a plurality of locations spaced apart from each other in a direction along the horizontal plane. Specifically, as shown in FIG. 3 to FIG. 5, the guide mechanism 37 includes four linear guide mechanisms 37a as a whole. Each linear guide mechanism 37a includes a guide body 37b fixed to the connecting part 31 and a moving body 37c fixed to the article support part 51 and moving along the guide body 37b. The guide body 37b is arranged so that the moving body 37c moves along the vertical direction Z. That is, the guide body 37b is arranged along the vertical direction Z. Here, the guide body 37b is a member that guides the moving body 37c so that it moves linearly, and in this example, is formed in a rail shape. The moving body 37c is engaged with the guide body 37b so that it moves linearly along the guide body 37b. In this example, the linear guide mechanism 37a is a linear guide.

[0040] In this embodiment, the guide body 37b is fixed to the interlocking member 42. Moreover, the movable body 37c is fixed to the gripping unit 50. As described above, the movable body 37c is guided to move in the vertical direction Z along the guide body 37b, and the gripping unit 50 is guided to move in the vertical direction Z relative to the interlocking member 42. That is, the gripping unit 50 is permitted to move parallel to the interlocking member 42 in the vertical direction Z. Meanwhile, the movable body 37c guided by the guide body 37b cannot move in any direction other than the vertical direction Z, and therefore the swinging of the gripping unit 50 in the width direction Y and the running direction X relative to the interlocking member 42 is restricted.

[0041] In addition, in this embodiment, the guide mechanism 37 includes a pair of linear guide mechanisms 37a arranged at a distance in the width direction Y for each of the pair of gripping parts 50. As shown in FIG. 4, the pair of linear guide mechanisms 37a corresponding to one gripping part 50 are arranged at a distance in the width direction Y. In this example, the pair of linear guide mechanisms 37a are attached to each of a pair of interlocking fixing parts 42a provided at both ends of the interlocking main body part 42b in the width direction Y. More specifically, the guide bodies 37b of the pair of linear guide mechanisms 37a are fixed to the interlocking fixing parts 42a. In this manner, the pair of linear guide mechanisms 37a are connected by the interlocking member 42. In addition, the pair of linear guide mechanisms 37a are arranged at positions overlapping the interlocking main body part 42b and the guided member 41 when viewed in the up-down direction Z. Furthermore, in this embodiment, the pair of linear guide mechanisms 37a are attached to the supported part 50b of the gripping part 50. More specifically, the moving bodies 37c of the pair of linear motion guide mechanisms 37a are fixed to the supported portions 50b. As a result, the gripping portion 50 is guided by the pair of linear motion guide mechanisms 37a so as to move parallel to the interlocking member 42 in the up-down direction Z.

[0042] The pair of gripping parts 50 are independent of each other. That is, as shown in Figs. 3 to 5, the pair of gripping parts 50 are supported by different elastic support mechanisms 36 and guided by different guide mechanisms 37. This allows the pair of gripping parts 50 to move in the up-down direction Z independently of each other with respect to the connecting part 31. Therefore, for example, as shown in Fig. 5, the positions of the pair of gripping parts 50 in the up-down direction Z may be different from each other.

[0043] In this way, the pair of gripping parts 50 are arranged apart from each other in the traveling direction X and move up and down independently, so that the swinging of the article 6 in the traveling direction X is permitted even though the above-mentioned guide mechanism 37 is provided. Generally, a load in the traveling direction X is often applied to the article 6 being transported by the article transport vehicle 1 due to acceleration / deceleration of the article transport vehicle 1. However, according to the configuration of this embodiment, the pair of gripping parts 50 move up and down independently from each other, so that the effect of the elastic support mechanism 36 to reduce the vibration in the direction in which the article 6 swings in the traveling direction X is not hindered by the guide mechanism 37. Meanwhile, even in the configuration of this embodiment, the guide mechanism 37 is configured to guide the movement of each of the pair of gripping parts 50 in the up-down direction Z relative to the connecting part 31, and is configured to restrict the swinging of each of the pair of gripping parts 50 relative to the connecting part 31, particularly the swinging in the width direction Y. Therefore, even if a load biased in the width direction Y acts on the pair of gripping parts 50 due to, for example, a bias in the width direction Y of the center of gravity of the article 6, the pair of gripping parts 50 can be prevented from tilting in the width direction Y with respect to the connecting part 31. Therefore, the article 6 supported by the pair of gripping parts 50 can be prevented from tilting in the width direction Y with respect to the connecting part 31. In this embodiment, the article 6 is a FOUP that contains multiple semiconductor substrates, and the lid body 5 (see FIG. 6) is transported by the article transport vehicle 1 in a state in which it is disposed on one side of the article 6 in the width direction Y. In the FOUP, the weight per unit volume of the lid body 5 is larger than that of other parts, and the position of the center of gravity in the width direction Y of the entire article 6 varies depending on the number of semiconductor substrates contained therein. However, according to the configuration of this embodiment, it is possible to prevent the article 6 from tilting in the width direction Y due to such a variation in the center of gravity.

[0044] In this embodiment, as shown in FIG. 4, in each of the pair of gripping parts 50, the pair of linear motion guide mechanisms 37a are disposed outside the pair of elastic bodies 36a in the width direction Y. Here, due to the principle of leverage, the load acting on the gripping portion 50 due to the swinging of the article 6 in the width direction Y is generally greater on the inside in the width direction Y than on the outside in the width direction Y. Therefore, the load acting on the linear guide mechanisms 37a can be reduced by arranging the pair of linear guide mechanisms 37a on the outside in the width direction Y of the pair of elastic bodies 36a, rather than arranging the pair of linear guide mechanisms 37a on the inside in the width direction Y of the pair of elastic bodies 36a. In this case, a relatively large load acts on the pair of elastic bodies 36a, but since the elastic bodies 36a generally have a simpler structure and higher strength than the linear guide mechanisms 37a and are easier to secure, no major problems are likely to occur.

[0045] [Item transfer operation] Next, an operation will be described in which the article 6 held by the holding device 23 is lowered by the lifting device 24 and placed (transferred) on the placement location 4 directly below.

[0046] Here, the position of the holding device 23 with respect to the running body 16 in a state where the article 6 is housed in the cover portion 25 is referred to as the running position (see FIG. 2). The lifting device 24 unwinds the winding belt 24a by the rotational drive of the lifting motor 29, and lowers the holding device 23 from the running position to the transfer position (see FIG. 6). By lowering the holding device 23 to the transfer position, the article 6 held by the holding device 23 is placed on the placement location 4. In this way, the transfer position is a position lower than the running position, and is the position of the holding device 23 with respect to the running body 16 in a state where the article 6 held by the holding device 23 is placed on the placement surface 4a of the placement location 4. With the holding device 23 in the transfer position and the article 6 placed on the placement surface 4a, the gripping drive mechanism 30 switches the distance between the pair of gripping parts 50 from a gripping distance for gripping the article 6 to a release distance for releasing the grip of the article 6. In this manner, the article 6 is transferred to the placement location 4. As described above, in this example, a plurality of engagement protrusions P for positioning are provided on the placement surface 4a of the placement location 4. Also, an engagement recess B for engaging with the engagement protrusions P is provided on the bottom surface 11a of the article 6. Then, when the holding device 23 is lowered to the transfer position with the article 6 in the proper posture, the engagement recess B of the article 6 is engaged with the engagement protrusion P of the placement location 4, and the article 6 is properly placed on the placement surface 4a of the placement location 4. In the following, the proper posture is defined as the posture of the article 6 that allows the engaging recess B of the article 6 to properly engage with the engaging protrusion P of the placement location 4 when the holding device 23 is lowered to the transfer position. In this embodiment, the placement surface 4a of the placement location 4 is disposed along a horizontal plane, and when the posture of the article 6 is in the proper posture, the bottom surface 11a of the article 6 is in a posture along the horizontal plane.

[0047] As a comparative example, a transfer operation will be described in which the holding device 23 does not include the linear motion guide mechanism 37a. In this case, the pair of gripping parts 50 are not restricted from swinging relative to the connecting part 31. Therefore, when the center of gravity of the article 6 is biased in the width direction Y, a biased load acts on the pair of gripping parts 50, and the pair of gripping parts 50 and the article 6 gripped thereby are tilted in the width direction Y with respect to the connecting part 31. For example, as in this embodiment, when the article 6 is a FOUP that stores a plurality of semiconductor substrates and the lid body 5 (see FIG. 7) is disposed on one side of the article 6 in the width direction Y, the weight per unit volume of the lid body 5 is larger than that of the other parts, so that the position of the center of gravity in the width direction Y of the entire article 6 varies depending on the number of semiconductor substrates stored therein. Specifically, as the number of semiconductor substrates decreases, the center of gravity of the article 6 is biased toward the lid body 5 in the width direction Y. When the holding device 23 does not include the linear guide mechanism 37a as in this comparative example, the pair of gripping parts 50 are elastically supported by the elastic support mechanism 36. Therefore, if the center of gravity of the article 6 is biased, it is not possible to prevent the pair of gripping parts 50 from tilting together with the article 6 to the side to which the center of gravity is biased, and the article 6 will tilt in the width direction Y with respect to the correct posture. When the holding device 23 is lowered to the transfer position with the article 6 tilted with respect to the correct posture in this way, the bottom surface 11a of the article 6 will be in a posture tilted with respect to the placement surface 4a, as shown in FIG. 7, for example. Therefore, there are cases in which the engaging recess B of the article 6 cannot properly engage with the engaging protrusion P of the placement location 4. In such a case, the article 6 cannot be properly placed on the placement location 4, and a transfer failure may occur.

[0048] In contrast, when the holding device 23 is provided with the linear guide mechanism 37a as in the present embodiment, the pair of gripping parts 50 as the article support part 51 are allowed to move in parallel in the vertical direction Z relative to the connecting part 31, and are restricted from swinging relative to the connecting part 31. Therefore, each of the pair of gripping parts 50 is elastically supported by the elastic support mechanism 36 in a state in which it is only allowed to move in parallel in the vertical direction Z. As described above, each of the pair of gripping parts 50 is formed to extend in the width direction Y, and supports the flange part 9 of the article 6 in a position along the width direction Y. Therefore, the article 6 is restricted from swinging in the width direction Y relative to the pair of gripping parts 50. As a result, even if a biased load acts on the pair of gripping parts 50 due to the center of gravity of the article 6 being biased in the width direction Y as described above, the position of each of the pair of gripping parts 50 relative to the connecting part 31 is maintained, and the article 6 is restricted from tilting relative to the connecting part 31. Therefore, when the lifting device 24 lowers the holding device 23 to the transfer position to place the article 6 on the placement location 4, the posture of the article 6 can be prevented from tilting with respect to the proper posture. By lowering the holding device 23 to the transfer position while maintaining the article 6 in the proper posture in this manner, the engaging recess B provided on the bottom surface 11a of the article 6 can be properly engaged with the engaging protrusion P provided on the placement surface 4a of the placement location 4, as shown in Fig. 6. In other words, the article 6 can be properly placed on the placement location 4 regardless of the deviation of the center of gravity of the article 6 in the width direction Y.

[0049] 2. Other embodiments Next, other embodiments of the article transport vehicle will be described.

[0050] (1) In the above embodiment, the elastic body 36a constituting the elastic support mechanism 36 provided between the item support part 51 and the connecting part 31 is a compression coil spring. However, the configuration of the elastic body 36a is not limited to this. By changing the arrangement of the elastic body 36a in the elastic support mechanism 36, other types of springs such as a tension coil spring may be used. In addition, for example, synthetic rubber or synthetic resin having elasticity may be used.

[0051] (2) In the above embodiment, the article support unit 51 includes a pair of gripping units 50, and the pair of gripping units 50 are arranged at a distance from each other in the travel direction X. However, the configuration of the article support unit 51 is not limited to this. For example, the pair of gripping units 50 may be arranged at a distance from each other in the width direction Y. This configuration is suitable for cases where the center of gravity of the article 6 is biased in the travel direction X and where a load in the width direction Y acts on the article 6 during transportation. Also, for example, the article support unit 51 may include a fork inserted into the insertion space 12 of the flange portion 9 instead of the pair of gripping units 50. Alternatively, the article support unit 51 may include a placement unit for placing and supporting the article 6 on a placement surface instead of the pair of gripping units 50. In these configurations, the entire integrally constructed item support part 51 is elastically supported by the elastic support mechanism 36 and is guided by the guide mechanism 37 so as to allow parallel movement in the vertical direction Z relative to the connecting part 31 while restricting oscillation relative to the connecting part 31 (oscillation in both the running direction X and the width direction Y).

[0052] (3) In the above embodiment, a configuration has been described as an example in which the pair of linear motion guide mechanisms 37a are disposed on the outer side of the pair of elastic bodies 36a in the width direction Y. However, the present invention is not limited to such a configuration, and for example, the pair of linear motion guide mechanisms 37a may be disposed on the inner side of the pair of elastic bodies 36a in the width direction Y.

[0053] (4) In the above embodiment, the pair of guide bodies 37b is fixed to the interlocking fixing portion 42a, and the pair of moving bodies 37c is fixed to the supported portion 50b. However, the present invention is not limited to this configuration, and for example, the pair of guide bodies 37b may be fixed to the supported portion 50b, and the pair of moving bodies 37c may be fixed to the interlocking fixing portion 42a.

[0054] (5) In the above embodiment, a linear guide is used as an example of the linear guide mechanism 37a constituting the guide mechanism 37. However, the configuration of the linear guide mechanism 37a is not limited to this. For example, various known linear guide mechanisms such as a ball spline, a linear bush, etc. may be used.

[0055] (6) In the above embodiment, as shown in FIG. 4, the guide mechanism 37 includes two linear guide mechanisms 37a for each of the pair of grippers 50, that is, four linear guide mechanisms 37a in total. However, the configuration of guide mechanism 37 is not limited to this. For example, three or more linear motion guide mechanisms 37a may be provided for one gripping part 50. Also, only one linear motion guide mechanism 37a may be provided for one gripping part 50. Furthermore, when article support part 51 is configured integrally, one or more linear motion guide mechanisms 37a may be provided for the integral article support part 51.

[0056] (7) In the above embodiment, an example has been described in which the article 6 has a flange portion 9 and an engaging recess B, and the placement location 4 has an engaging protrusion P that engages with the engaging recess B. However, the present invention is not limited to this configuration, and may be configured, for example, such that the article 6 does not have the engaging recess B, and the placement location 4 does not have the engaging protrusion P. Even in such a configuration, the configuration of the above embodiment prevents the article 6 from being placed in an inclined position relative to the placement surface 4a of the placement location 4, thereby allowing the article 6 to be properly placed on the placement location 4.

[0057] (8) The configurations disclosed in the above-described embodiments can be applied in combination with configurations disclosed in other embodiments, as long as no contradiction occurs. As for other configurations, the embodiments disclosed in this specification are merely examples in all respects. Therefore, various modifications can be made as appropriate within the scope of the present disclosure.

[0058] 3. Overview of the above embodiment The above-described article transport vehicle will now be outlined.

[0059] The article transport vehicle comprises a running body that runs along a travel path, a holding device that holds an article, and a lifting device mounted on the running body and raising and lowering the holding device relative to the running body, wherein the holding device comprises a connecting portion connected to the lifting device, and an article support portion that contacts the article and supports the article, and the holding device comprises an elastic support mechanism that is provided between the article support portion and the connecting portion and supports the article support portion in a vertically elastic state relative to the connecting portion, and a guide mechanism that guides the vertical movement of the article support portion relative to the connecting portion, and the guide mechanism is configured to allow parallel movement of the article support portion in the vertical direction relative to the connecting portion and to regulate the swinging of the article support portion relative to the connecting portion.

[0060] According to this configuration, since an elastic support mechanism is provided between the article support part and the connecting part, the elastic support mechanism can attenuate vibrations of the running body caused by the running of the running body, vibrations of the holding device caused by the lifting device being raised and lowered, etc. Therefore, the vibrations transmitted to the articles can be reduced. In addition, according to this configuration, since the guide mechanism is configured to restrict the swinging of the article support part relative to the connecting part, it is possible to restrict the article support part from tilting relative to the connecting part. Therefore, even if an uneven load acts on the article support part due to, for example, an uneven center of gravity of the article, it is possible to restrict the article support part and the article supported by the article support part from tilting relative to the connecting part. Therefore, when the holding device is lowered by the lifting device to place the article on the placement location, it is possible to avoid a situation in which the article cannot be placed properly because the posture of the article is tilted from the correct posture. Meanwhile, the guide mechanism allows the article support part to move in parallel in the vertical direction relative to the connecting part. Therefore, the effect of the elastic support mechanism to reduce the vertical vibration acting on the article support part and the article supported by the article support part is not hindered by the guide mechanism. Thus, with this configuration, it is possible to minimize vibrations transmitted to the article, while preventing the article from tilting relative to the correct posture, thereby enabling the article to be properly placed on the placement location.

[0061] Here, it is preferable that the item support portion comprises a pair of gripping portions which are arranged at a distance from each other in the running direction which is the direction along the running path, the elastic support mechanism supports the pair of gripping portions so that the pair of gripping portions move up and down independently of each other, and the guide mechanism is configured to guide the up and down movement of each of the pair of gripping portions relative to the connecting portion.

[0062] Generally, a load in the running direction is applied to an article being transported by an article transport vehicle due to acceleration and deceleration of the article transport vehicle. According to this configuration, the pair of gripping parts are arranged apart from each other in the running direction and are supported by the elastic support mechanism so as to move up and down independently, so that even in a configuration with the above-mentioned guide mechanism, the article is allowed to swing in the running direction. Therefore, the effect of the elastic support mechanism to reduce the vibration in the direction in which the article swings in the running direction is not hindered by the guide mechanism. On the other hand, even in this configuration, the guide mechanism is configured to guide the vertical movement of each of the pair of gripping parts relative to the connecting part, with the direction perpendicular to the running direction when viewed in the up-down direction being the width direction, and is configured to restrict the swinging of each of the pair of gripping parts relative to the connecting part. Therefore, even if a load biased in the width direction acts on the article support part due to, for example, a bias in the width direction of the center of gravity of the article, the article support part can be restricted from tilting in the width direction relative to the connecting part. Therefore, the article supported by the article support part can be restricted from tilting in the width direction relative to the connecting part. This configuration is suitable for cases where the center of gravity of the article is often biased in the width direction.

[0063] Furthermore, with a direction perpendicular to the running direction when viewed in the up-down direction along the up-down direction being defined as a width direction, it is preferable that the elastic support mechanism includes a pair of elastic bodies arranged at a distance in the width direction for each of the pair of gripping portions, and the guide mechanism includes a pair of linear guide mechanisms arranged at a distance in the width direction for each of the pair of gripping portions, and that in each of the pair of gripping portions, the pair of linear guide mechanisms are arranged outside the pair of elastic bodies in the width direction.

[0064] According to this configuration, the load acting on the linear guide mechanism can be made smaller than when the pair of linear guide mechanisms are disposed on the inner side in the width direction of the pair of elastic bodies, making it easier to avoid an increase in size and cost of the linear guide mechanism.

[0065] It is also preferable that the guide mechanism comprises linear guide mechanisms arranged at multiple locations spaced apart from each other in a direction along a horizontal plane, each of the linear guide mechanisms comprising a guide body fixed to one of the connecting portion and the item support portion, and a moving body fixed to the other of the connecting portion and the item support portion and moving along the guide body, and that the guide body is arranged so that the moving body moves along the vertical direction.

[0066] According to this configuration, since the linear guide mechanisms are arranged at multiple locations spaced apart from each other in a direction along the horizontal plane, it is easy to keep the load acting on each linear guide mechanism relatively small. In addition, the linear guide mechanisms arranged at multiple locations make it easy to stably support the article support unit.

[0067] It is also preferable that the item is a container having a flange portion provided at the top and an engagement recess provided at the bottom, and when the item is lowered by the lifting device and placed on a placement location, the engagement recess engages with a positioning engagement protrusion provided at the placement location, and the item support portion is configured to grasp the flange portion with a pair of gripping portions.

[0068] According to this configuration, when the article is placed on the placement location, the engaging recess engages with the engaging protrusion, so that the container can be appropriately placed at an appropriate position on the placement location. Also, the article support part can appropriately hold the article in a suspended state by gripping the flange part with the pair of gripping parts. [Industrial Applicability]

[0069] The technology disclosed herein can be used in an article transport vehicle that travels along a travel path. [Explanation of symbols]

[0070] 1: Ceiling transport vehicle (goods transport vehicle) 6: Goods 9: Flange part 11: Bottom 23: Holding device 24: Lifting device 31:Connection part 32: Article support part 50: Grip part 36: Elastic support mechanism 36a: Elastic body 37: Guiding mechanism 37a: Linear guide mechanism B: Engagement recess P: Engagement protrusion X: Traveling direction Y: Width direction Z: Vertical direction

Claims

1. The present invention comprises a running body that runs along a running path, a holding device that holds an article, and a lifting device that is mounted on the running body and lifts and lowers the holding device relative to the running body, The holding device is an article transport vehicle including a connecting portion connected to the lifting device, an article support portion that contacts the article to support the article, and a gripping guide mechanism, the holding device comprises: an elastic support mechanism provided between the article support portion and the connecting portion, which supports the article support portion in a vertically elastic state relative to the connecting portion; and a guide mechanism which guides the vertical movement of the article support portion relative to the connecting portion, the guide mechanism is configured to allow translation of the article support part relative to the connecting part in the up-down direction and to restrict swinging of the article support part relative to the connecting part, The article support portion includes a pair of gripping portions, The direction in which the pair of gripping portions are arranged is defined as an arrangement direction, The pair of gripping portions are disposed spaced apart from each other in the arrangement direction and are configured to move toward and away from each other along the arrangement direction, the guide mechanism includes a first guide mechanism and a second guide mechanism that are spaced apart from each other in the arrangement direction so as to correspond to the pair of gripping portions, the gripping guide mechanism is supported by the connecting portion and configured to guide movement of the pair of gripping portions in the arrangement direction, One of the pair of gripping portions is a first gripping portion, and the other of the pair of gripping portions is a second gripping portion, the elastic support mechanism includes a first elastic support mechanism corresponding to the first gripping portion and a second elastic support mechanism corresponding to the second gripping portion, the first gripping portion is supported by the gripping guide mechanism via the first guide mechanism and the first elastic support mechanism, The second gripping portion is supported by the gripping guide mechanism via the second guide mechanism and the second elastic support mechanism.

2. The arrangement direction is the same as the traveling direction, which is a direction along the traveling path, the elastic support mechanism supports the pair of gripping portions so that the pair of gripping portions can move up and down independently of each other, The article transport vehicle according to claim 1 , wherein the guide mechanism is configured to guide the vertical movement of each of the pair of grippers relative to the connecting portion.

3. The direction perpendicular to the running direction when viewed in the vertical direction is defined as the width direction, The elastic support mechanism includes a pair of elastic bodies arranged spaced apart in the width direction for each of the pair of gripping portions, The guide mechanism includes a pair of linear guide mechanisms arranged spaced apart in the width direction for each of the pair of gripping portions, 3. The article transport vehicle according to claim 2, wherein in each of the pair of gripping portions, the pair of linear motion guide mechanisms are disposed outboard of the pair of elastic bodies in the width direction.

4. the guide mechanism includes linear motion guide mechanisms arranged at a plurality of locations spaced apart from one another in a direction along a horizontal plane, each of the linear motion guide mechanisms includes a guide body fixed to one of the connecting portion and the article support portion, and a movable body fixed to the other of the connecting portion and the article support portion and movable along the guide body; The article transport vehicle according to claim 1 , wherein the guide body is disposed so that the movable body moves along the vertical direction.

5. The article is a container having a flange portion provided on an upper portion and an engagement recess portion provided on a bottom portion, When the lifting device is lowered and placed on a placement location, the engagement recess is engaged with a positioning engagement protrusion provided on the placement location, The article transport vehicle according to claim 1 , wherein the article support portion is configured to grip the flange portion with a pair of the gripping portions.

6. An article transport vehicle as described in any one of claims 1 to 5, wherein the gripping guide mechanism moves the first gripping portion, the first guide mechanism, and the first elastic support mechanism integrally along the alignment direction, and moves the second gripping portion, the second guide mechanism, and the second elastic support mechanism integrally along the alignment direction.

7. The present invention comprises a running body that runs along a running path, a holding device that holds an article, and a lifting device that is mounted on the running body and lifts and lowers the holding device relative to the running body, The holding device is an article transport vehicle including a connecting portion connected to the lifting device, an article support portion that contacts the article to support the article, and a gripping guide mechanism, the holding device comprises: an elastic support mechanism provided between the article support portion and the connecting portion, which supports the article support portion in a vertically elastic state relative to the connecting portion; and a guide mechanism which guides the vertical movement of the article support portion relative to the connecting portion, the guide mechanism is configured to allow translation of the article support part relative to the connecting part in the up-down direction and to restrict swinging of the article support part relative to the connecting part, The article support portion includes a pair of gripping portions, The direction in which the pair of gripping portions are arranged is defined as an arrangement direction, The pair of gripping portions are disposed spaced apart from each other in the arrangement direction, the guide mechanism is configured to guide the vertical movement of each of the pair of gripping portions relative to the connecting portion, the guide mechanism includes a first guide mechanism and a second guide mechanism that are spaced apart from each other in the arrangement direction so as to correspond to the pair of gripping portions, One of the pair of gripping portions is a first gripping portion, and the other of the pair of gripping portions is a second gripping portion, an arrangement area of ​​the first guide mechanism in the arrangement direction overlaps with an arrangement area of ​​a portion of the first gripping portion that is lower than the connecting portion in the arrangement direction; An article transport vehicle, wherein the placement area of ​​the second guide mechanism in the arrangement direction overlaps with the placement area of ​​a portion of the second gripping portion below the connecting portion in the arrangement direction.

8. The elastic support mechanism includes a first elastic support mechanism corresponding to the first gripping portion and a second elastic support mechanism corresponding to the second gripping portion, an arrangement area of ​​the first guide mechanism in the arrangement direction further overlaps with an arrangement area of ​​the first elastic support mechanism in the arrangement direction; The article transport vehicle according to claim 7 , wherein an arrangement area of ​​the second guide mechanism in the arrangement direction further overlaps an arrangement area of ​​the second elastic support mechanism in the arrangement direction.

Images