Article Transport Vehicle

An article transport vehicle includes a body, a wheel held by the body, a motor that drives the wheel, and a driver unit that controls the motor. The driver unit is disposed to extend in a front-back direction of the body in an upright posture. The body is provided, in a bottom section thereof, with an air guide path configured to guide travel-generated wind to a cooling surface.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Japanese Patent Application No. 2023-025519 filed Feb. 21, 2023, the disclosure of which is hereby incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an article transport vehicle.

2. Description of Related Art

In facilities where articles stored, sorted and the like, for example, article transport vehicles that transport articles are utilized. An example of such an article transport vehicle is disclosed in JP 2021-181362A (Patent Document 1).

The article transport vehicle (unmanned transport vehicle1) of Patent Document 1 includes a body (base10), wheels (wheels12), and a motor (motor) for driving the wheels, and, although not explicitly shown, is considered to include a driver unit. The driver unit often includes a plurality of semiconductor elements, and requires cooling due to heat generated during operation. Also, it is preferable that the driver unit is installed in relation to other constituent components in such a manner as to facilitate downsizing of the article transport vehicle as a whole. In this regard, Patent Document 1 does not particularly disclose how the driver unit is installed or the way in which the driver unit is efficiently cooled.

SUMMARY OF THE INVENTION

In view of the above, it is desirable to realize an article transport vehicle that is readily downsized as a whole and is able to efficiently cool the driver unit.

An article transport vehicle according to the present disclosure is:

An article transport vehicle for transporting an article, including:a body;a wheel held by the body;a motor configured to drive the wheel; anda driver unit configured to control the motor,wherein the driver unit is disposed to extend vertically and in a front-back direction of the body,in the driver unit, at least one surface facing in a width direction orthogonal to the front-back direction as viewed in an up-down direction is a cooling surface, andthe body is provided, in a bottom section thereof, with an air guide path configured to guide travel-generated wind to the cooling surface.

According to this configuration, disposing the driver unit to extend in the front-back direction of the body in an upright posture facilitates both securing a large internal space in the body and downsizing of the article transport vehicle as a whole. Given that the surfaces of the driver unit disposed in an upright posture to extend in the front-back direction of the body that face in the width direction have the largest area, cooling efficiency can be enhanced by using at least one of these surfaces as the cooling surface. Furthermore, the driver unit can be cooled more efficiently, by directing travel-generated wind through the air guide path to the cooling surface, when the article transport vehicle is travelling. These factors enable an article transport vehicle to be realized that is readily downsized as a whole and is able to efficiently cool the driver unit.

Further features and advantages of the technology according to the present disclosure will become apparent from the following description of exemplary and non-limiting embodiments which will be described with reference to the drawings.

DESCRIPTION OF THE INVENTION

An embodiment of an article transport vehicle will be described with reference to the drawings. An article transport vehicle1of the present embodiment is used for transporting articles A in a facility (hereinafter referred to as “logistics facility”) where the articles A are stored, sorted, and the like, for example.

As shown inFIG.1, the article transport vehicle1includes a body2and a transfer device9that is mounted on the body2and transfers the articles A. The body2travels on a travel surface F (seeFIG.2). The travel surface F is, for example, a floor surface of the logistics facility. Hereinafter, the direction in which the article transport vehicle1(body2) advances when traveling will be referred to as the “front-back direction X”, a normal direction of the travel surface F will be referred to as the “up-down direction Z”, and a direction perpendicular to the front-back direction X as viewed in the up-down direction Z will be referred to as the “width direction Y”. Also, the forward direction side, which is one side in the front-back direction X, may be referred to as the “front side”, and the opposite side thereto may be referred to as the “back side”.

The transfer device9includes a transfer tray91. The transfer device9is switchable between a horizontal posture in which the transfer tray91is disposed horizontally along the upper surface of the body2(seeFIG.1) and an inclined posture in which the transfer tray91is inclined with respect to the upper surface of the body2(seeFIG.2). The transfer device9is able to place an article A on the transfer tray91in the horizontal posture. Also, as shown inFIG.2, the transfer device9is able to slidingly transfer the article A from the transfer tray91, by changing the transfer tray91from the horizontal posture to the inclined posture.

The article transport vehicle1is able to travel to a destination within the logistics facility with an article A placed on the transfer tray91in the horizontal posture, and to transport and deliver the article A to the destination with the transfer tray91in the inclined posture. Note that, as the destination within the logistics facility, an article input section T that inputs articles A sorted by shipping destination, such as shown inFIG.2, for example, is given as an example.

Note that the article transport vehicle1of the present embodiment is an unmanned transport vehicle capable of unmanned travel. The article transport vehicle1includes a reading device7, and is capable of unmanned travel while grasping its own position, due to the reading device7sequentially reading position information recorded in a plurality of position information storage sections B provided intermittently on the travel surface F. Examples of the position information storage sections B include barcodes such as one-dimensional codes and two-dimensional codes, RFID (Radio Frequency Identification) tags, and the like. As the reading device7, a barcode reader, a tag reader, or the like is utilized, according to the type of location information storage section B.

FIG.3is an exploded perspective view showing the structure of the body2, out of the body2and the transfer device9constituting the article transport vehicle1(illustration of the transfer device9is omitted). As shown inFIG.3, the body2has a main body20and a cover29that is detachably attached to the main body20from above. Apart from the body2having the main body20and the cover29, the article transport vehicle1includes a travel drive section4, a control device5, a power supply device6, and a cable8, as also shown inFIGS.5and6.

The main body20includes a base21capable of supporting the travel drive section4, the control device5, the power supply device6, and the cable8. The base21is formed in a rectangular shape (in this example, a rectangular shape approximating a square in which portions of the four corners are chamfered) as viewed in the up-down direction. The base21has a flat bottom section22and a central ridge section23that rises upward from the bottom section22in a central portion thereof in the front-back direction X. Note that, on the back surface (lower surface) side of the central ridge section23, there is a space recessed upward from a bottom surface22aof the bottom section22, as shown inFIG.4, with this space constituting a wheel housing space23a.

In the present embodiment, a travel drive support space Sd is constituted by the wheel housing space23aon the back surface side of the central ridge section23of the base21. Also, a control device support space Sc is constituted by a space on the front side, which is one side in the front-back direction X relative to the central ridge section23on the base21. Also, a power supply device support space Sp is constituted by a space on the back side, which is the opposite side in the front-back direction X relative to the central ridge section23on the base21.

As shown inFIGS.4and5, the travel drive section4is disposed in the travel drive support space Sd (wheel housing space23a). The travel drive section4is thereby held by a central portion of the body2in the front-back direction X. Here, in the present embodiment, the travel drive section4includes a pair of wheels41and a pair of travel motors42for driving the wheels41. The pair of wheels41are separated from each other in the width direction Y. The pair of travel motors42are each disposed on the same axis as the corresponding wheel41so as to be adjacent thereto in the width direction Y, and are coupled so as to rotate as one with the corresponding wheel41. In the present embodiment, the travel motors42correspond to a “motor”.

The wheel housing space23aof the present embodiment is divided in two in the width direction Y, by an atrium-like window section25formed in a central portion of the base21in the width direction Y. A first set of a wheel41and a travel motor42is disposed in one of the two wheel housing spaces23a,and a second set of a wheel41and a travel motor42is disposed in the other of the two wheel housing spaces23a.That is, a first wheel41A and a first travel motor42A are disposed in one of the two wheel housing spaces23a,and a second wheel41B and a second travel motor42B are disposed in the other of the two wheel housing spaces23a.

Note that, in the window section25formed in the base21, the reading device7is supported in such a manner as to be disposed facing the bottom surface22aside (travel surface F side) of the bottom section22. The reading device7is disposed between the first wheel41A and the second wheel41B of the body2in the width direction Y, and, more specifically, is disposed between the first travel motor42A and the second travel motor42B in the width direction Y.

In the present embodiment, at the end portions on the base21in the front-back direction X are formed recessed sections22bthat are separated from each other in the width direction Y and recessed in a round hole shape. In at least one of the recessed sections22bis disposed an auxiliary wheel44.FIG.4shows an example in which auxiliary wheels44are disposed in only two recessed sections22blocated diagonally, out of the four recessed sections22b,but auxiliary wheels44may, for example, be disposed in all four of the recessed sections22b.

As shown inFIG.3, in the present embodiment, on the front side, which is one side in the front-back direction X relative to the central ridge section23of the base21, is formed an extended ridge section24that rises upward from the bottom section22in the same manner as the central ridge section23. The extended ridge section24is provided on each side of the base21in the width direction Y. Also, the extended ridge sections24are integrally provided continuously with the central ridge section23in the front-back direction X. In other words, portions on both sides of the central ridge section23in the width direction Y are extended on the front side, which is one side in the front-back direction X, with these extended portions being the extended ridge sections24. The extended ridge sections24are provided in the control device support space Sc.

Note that, on the back surface (lower surface) side of the extended ridge sections24, there are spaces that are recessed upward from the bottom surface22aof the bottom section22, as shown inFIG.4, with these spaces constituting recessed spaces24a.These recessed spaces24aare integrally formed continuously with the wheel housing spaces23ain the front-back direction X. Unlike the wheel housing spaces23a,constituent components of the article transport vehicle1are not disposed in the recessed spaces24a.The recessed spaces24aconstitute part of an air passageway30through which wind that is generated by travel of the article transport vehicle1passes.

As shown inFIGS.3and5, the control device5is disposed in the control device support space Sc. The control device5is thereby supported on the front side of the body2, which is one side in the front-back direction X relative to the travel drive section4. Here, the control device5is a constituent component for controlling the travel motors42, and, in the present embodiment, includes at least a driver unit51and a control board52(omitted inFIG.3).

The driver unit51is a unit for rotationally driving the travel motor42and has a driver circuit that includes a semiconductor element. In the present embodiment, a pair of driver units51is also provided in correspondence with the pair of travel motors42. That is, a first driver unit corresponding to the first travel motor42A and a second driver unit corresponding to the second travel motor42B are provided as the driver units51.

The driver units51are each formed in a rectangular parallelepiped shape. The driver units51of the present embodiment are each formed in a flat rectangular parallelepiped shape in which the length of one of the three sides extending orthogonally to each other from each vertex is significantly shorter (e.g., less than ⅓) compared to the length of the other two sides. The surface constituted by the two long sides of the driver unit51has the largest area, and there are two such surfaces having the largest area that oppose each other. In the present embodiment, the two surfaces having the largest area and facing in opposite directions to each other will be referred to as a first surface51aand a second surface51b.

As shown inFIG.3, the flat rectangular parallelepiped driver units51are disposed to extend in the front-back direction X of the body2in an upright posture. Here, “upright posture” means a posture in which the length (height) in the up-down direction Z is longer than at least one of the length in the front-back direction X and the length in the width direction Y. In other words, “upright posture” means a posture in which the first surface51aand the second surface51b,which are the two surfaces having the largest area and facing in opposite directions each other, face in the width direction Y (posture in which the first and second surfaces51aand51bextend in the up-down direction Z and the front-back direction X). In the present embodiment, the driver units51are fixed to the base21in an upright posture in which the longest side extends in the front-back direction X.

Also, the driver units51are respectively fixed to the extended ridge sections24of the base21. In the present embodiment, one of the two surfaces (first surface51aand second surface51b) of each driver unit51that face in the width direction Y is a cooling surface51c(second surface51bin the example inFIG.3). The cooling surface51cof the driver units51is a surface to be cooled in order to protect the built-in semiconductor elements. As shown inFIG.7, uneven structures for promoting heat dissipation such as fins or pins, for example, are preferably formed on the cooling surface51c.

In the lateral surface (inner lateral surface24B; seeFIG.5) of each extended ridge section24of the base21that faces inward in the width direction Y (toward the center of the body2in the width direction Y) is formed a rectangular opening section35such as shown inFIG.7. The driver units51are respectively fixed to the extended ridge sections24so as to cover the opening sections35. The driver units51are respectively fixed to the inner lateral surfaces24B of the extended ridge sections24, such that the cooling surfaces51cface the recessed spaces24athrough the opening sections35.

Also, in the present embodiment, as shown inFIG.7, in a lower end portion on the front side of the base21(bottom section22) of the main body20in the front-back direction X is formed a lower opening31that is open in the front-back direction X. This lower opening31communicates with a diameter expansion section32whose height in the up-down direction Z gradually increases toward the back side in the front-back direction X, and further communicates with the recessed space24adescribed above via this diameter expansion section32.

When the article transport vehicle1travels forward, wind acts on the article transport vehicle I due to the relative movement thereof. This wind will be referred to as “travel-generated wind” in the present embodiment. This travel-generated wind is directed from the lower opening31through the diameter expansion section32to the recessed space24a.The travel-generated wind then reaches the cooling surface51cof the driver unit51exposed through the opening section35in the recessed space24a,and cools the driver unit51through heat exchange with the cooling surface51c.After cooling the driver unit51, the travel-generated wind passes from the recessed space24avia the wheel housing spaces23ato outside of the body2.

In the present embodiment, the air passageway30through which the travel-generated wind

passes is constituted by a space that extends from the lower opening31to the recessed space24avia the diameter expansion section32, and further extends to the wheel housing space23a.The air passageway30is disposed such that at least one (both in this example) of the travel drive section4and the power supply device6overlaps with the disposition region thereof in the width direction Y.

The control board52controls the travel motor42by controlling operation of the semiconductor elements included in the driver units51. The control board52is constituted by mounting various electronic components on an insulated board. As shown inFIG.5, the control board52is disposed in the control device support space Sc at a position on the front side, which is one side in the front-back direction X. Since the control device support space Sc is located on the front side of the body2in the front-back direction X, the control board52is disposed near the front end of the entirety of the body2in the front-back direction X. Also, the control board52spans substantially the entire control device support space Sc in the width direction Y.

As can be seen fromFIGS.3and6, the control device5is disposed at a position overlapping with the travel drive section4as viewed in the front-back direction X. In the present embodiment, the driver units51constituting the control device5entirely overlap with the travel drive section4as viewed in the front-back direction X. Part of the control board52(specifically, roughly half thereof in the up-down direction Z) overlaps with the travel drive section4as viewed in the front-back direction X.

In the present embodiment, a transfer drive section92is disposed in the control device support space Sc, in addition to the control device5. The transfer drive section92is thereby supported on the front side of the body2, which is one side in the front-back direction X relative to the travel drive section4, similarly to the control device5. The transfer drive section92is thus supported by a portion of the body2on the control device5side relative to the travel drive section4. Here, the transfer drive section92is a configuration for controlling the posture change of the transfer tray91as part of the transfer device9, and, in the present embodiment, includes at least a tilting mechanism93and a transfer motor94.

In the present embodiment, the tilting mechanism93is constituted by a tilt lever that includes a link mechanism. The tilting mechanism93is fixed to the transfer tray91, and is coupled to the transfer motor94. The transfer motor94switches the transfer tray91between the horizontal posture and the inclined posture via the tilting mechanism93, by driving rotationally. Note that the control board52described above also controls operation of the transfer motor94.

In the present embodiment, as shown inFIG.5, the tilting mechanism93is disposed on the back side of the control device support space Sc in the front-back direction X. The tilting mechanism93is disposed adjacent to the travel drive section4on the front side relative thereto in the front-back direction X. Also, the transfer motor94is disposed in a central portion of the control device support space Sc in the width direction Y. The transfer motor94is disposed over at least half of the region occupied by the control device support space Sc in the front-back direction X.

As can be seen fromFIG.6, the transfer motor94overlaps with the travel drive section4as viewed in the front-back direction X. In the present embodiment, part of the transfer motor94(specifically, roughly half thereof in the up-down direction Z) overlaps with the travel drive section4as viewed in the front-back direction X. All or most of the tilting mechanism93is disposed upward of the travel drive section4.

As shown inFIGS.3and5, the power supply device6is disposed in the power supply device support space Sp. The power supply device6is thereby supported on the back side of the body2, which is the opposite side in the front-back direction X relative to the travel drive section4. Here, the power supply device6is a constituent component for supplying power to at least the travel motors42, and, in the present embodiment, also supplies power to the transfer motor94and the reading device7. A secondary battery such as a lithium-ion battery, an electrolytic capacitor, an electric double layer capacitor, or the like, for example, can be used as the power supply device6.

The power supply device6is disposed on the front side of the power supply device support space Sp in the front-back direction X. The power supply device6is disposed adjacent to the travel drive section4on the back side relative thereto in the front-back direction X. The power supply device6is a disposed over at least half of the region occupied by the power supply device support space Sp in the front-back direction X. Also, the power supply device6is disposed over substantially the entire region of the power supply device support space Sp in the width direction Y.

In the present embodiment, in the power supply device support space Sp is disposed a power receiving section65, in addition to the power supply device6. The power receiving section65is thereby supported on the back side of the body2, which is the opposite side in the front-back direction X relative to the travel drive section4, similarly to the power supply device6. The power receiving section65is thus supported by a portion of the body2on the power supply device6side relative to the travel drive section4. Here, the power receiving section65is a constituent component for receiving power during charging of the power supply device6. The power receiving section65may, for example, be a connector in the case where charging of the power supply device6is performed by cable through a power line, or a power receiving coil in the case charging of the power supply device6is performed contactlessly.

The power receiving section65is disposed near the back end of the power supply device support space Sp in the front-back direction X. Since the power supply device support space Sp is located on the back side of the body2in the front-back direction X, the power receiving section65is disposed at the back end of the entirety of the body2in the front-back direction X. Also, the power receiving section65is disposed in a central portion of the power supply device support space Sp in the width direction Y.

As can be seen fromFIG.6, the power supply device6overlaps with the travel drive section4as viewed in the front-back direction X. In the present embodiment, part of the power supply device6(specifically, roughly half thereof in the up-down direction Z) overlaps with the travel drive section4as viewed in the front-back direction X. The power receiving section65also overlaps with the travel drive section4as viewed in the front-back direction X. In the present embodiment, part of the power receiving section65(specifically, roughly half thereof in the up-down direction Z) overlaps with the travel drive section4as viewed in the front-back direction X.

In the present embodiment, the driver units51, the tilting mechanism93, the transfer motor94, the power supply device6, the power receiving section65, and the reading device7that are supported by the main body20are all disposed to fit within the region occupied by the control board52in the up-down direction Z. Therefore, a neat and compact rectangular parallelepiped body2is realized in which the dimensions in the up-down direction Z are kept small.

Also, focusing on the disposition of relatively heavy components, the pair of travel motors42are disposed in a central portion in the front-back direction X, the transfer motor94is disposed on the front side relative thereto, and the power supply device6is disposed on the back side, which is the opposite side thereto, as shown inFIG.5. Adopting such a disposition configuration optimizes the weight balance of the body2in the front-back direction X.

The cable8electrically connects at least the control device5and the power supply device6. In the present embodiment, a plurality of cables8are provided, with another cable8electrically connecting the control device5and the reading device7. The cables8are disposed in a wiring space Sw provided to extend across the travel drive section4in the front-back direction X. Here, the wiring space Sw being provided to “extend across the travel drive section4in the front-back direction X” means that the wiring space Sw passes beyond the region occupied by the travel drive section4at a position overlapping with the travel drive section4as viewed in the up-down direction Z and extends to both sides thereof in the front-back direction X. In the present embodiment, the wiring space Sw extends across the travel drive section4in the front-back direction X from above the travel drive section4.

In the present embodiment, the wiring space Sw is disposed lower than whichever of the uppermost part of the control device5(here, the uppermost part of the control board52) and the uppermost part of the power supply device6is higher. Here, the wiring space Sw is disposed lower than both the uppermost part of the control device5and the uppermost part of the power supply device6.

In the present embodiment, a region including at least the upper surfaces of both end portions of the central ridge section23of the base21in the width direction Y and the upper surfaces of the extended ridge sections24is part of the wiring space Sw. In the present embodiment, the wiring space Sw includes a region toward the center (reading device7side) of the central ridge section23in the width direction Y and a region on the outer side of the power supply device6(outer edge side of the base21) in the width direction Y. The wiring space Sw is accessible from above with the cover29removed from the main body20, as shown inFIG.3. With such a configuration, the operator is able to easily operate the cables8from above, during maintenance and the like, for example.

As shown inFIGS.3and5, in the wiring space Sw is provided a cable holding section26for holding the cables8. In the present embodiment, the cable holding section26is provided at both end portions of the central ridge section23of the base21in the width direction Y. Two cable holding sections26are provided on each side in the width direction Y so as to be separated from each other in the front-back direction X.

As shown inFIGS.8and9, the cable holding section26of the present embodiment includes a pair of clamp arms27extending upward and disposed opposing each other in the width direction Y. The cable holding section26holds the cable8with the cable8housed between the pair of clamp arms27.

In the present embodiment, the pair of clamp arms27are provided at upper end portions thereof with protruding pieces27A that protrude inward (face each other). The protruding pieces27A can be latched onto the uppermost cable8housed between the pair of clamp arms27, and prevent the cable8from disengaging upward.

Other Embodiments

(1) In the above embodiment, a configuration in which the cables8are disposed in the wiring space Sw provided so as to extend across the travel drive section4in the front-back direction X is described as an example. However, the disclosure is not limited to such a configuration, and the wiring space Sw may be provided so as to pass on the outer side of the travel drive section4in the width direction Y, for example, and not extend across the travel drive section4, and the cables8may be disposed in that wiring space Sw.

(2) In the above embodiment, a configuration in which the cables8is disposed above the travel drive section4is described as an example. However, the disclosure is not limited to such a configuration, and the cables8may be disposed below the travel drive section4. Such a configuration can be suitably applied in the case where, for example, the outer diameter of the travel motors42is significantly smaller than the outer diameter of the wheels41.

(3) In the above embodiment, a configuration in which the travel drive section4, the control device5, and the power supply device6overlap each other as viewed in the front-back direction X is described as an example. However, the disclosure is not limited to such a configuration, and a configuration may be adopted in which at least one of the travel drive section4, the control device5, and the power supply device6does not overlap with the others thereof as viewed in the front-back direction X.

(4) In the above embodiment, a configuration in which the wiring space Sw is accessible from above with the cover29removed from the body20is described as an example. However, the disclosure is not limited to such a configuration, and, for example, a configuration may be adopted in which the wiring space Sw is only accessible from the side (outer side in the width direction Y) with the cover29removed from the main body20. Such a configuration can be suitably applied in the case where, for example, the cables8are disposed below the travel drive section4.

(5) In the above embodiment, a configuration in which the cable holding section26includes a pair of clamp arms27is described as an example. However, the disclosure is not limited to such a configuration, and the cable holding section26may be constituted by a band, clip, tape, or the like, for example, as long as the cables8can be held without issue.

(6) In the above embodiment, a configuration in which the transfer drive section92is supported by a portion on the control device5side relative to the travel drive section4in the front-back direction X is described as an example. However, the disclosure is not limited to such a configuration, and the transfer drive section92may be supported in the same region in the front-back direction X as the travel drive section4, for example. Alternatively, the transfer drive section92may be supported by a portion on the power supply device6side relative to the travel drive section4in the front-back direction X.

(7) In the above embodiment, a configuration in which the power receiving section65is supported by a portion on the power supply device6side relative to the travel drive section4in the front-back direction X is described as an example. However, the disclosure is not limited to such a configuration, and the power receiving section65may be supported by the same region in the front-back direction X as the travel drive section4, for example. Alternatively, the power receiving section65may be supported by a portion on the control device5side relative to the travel drive section4in the front-back direction X.

(8) In the above embodiment, a configuration in which the reading device7is disposed between the pair of wheels41in the width direction Y in the same region in the front-back direction X as the wheels41is described as an example. However, the disclosure is not limited to such a configuration, and the reading device7may be disposed in a different region in the front-back direction X from the wheels41, such as in a portion on the control device5side relative to the travel drive section4or in a portion on the power supply device6side relative to the travel drive section4, for example.

(9) In the above embodiment, a configuration in which the driver units51are formed in a rectangular parallelepiped shape is described as an example. However, the disclosure is not limited to such a configuration, and the driver units51may be formed in other shapes such as trapezoidal, triangular, and semicircular, for example, as viewed in the width direction Y, as long as the driver units51can at least be disposed in an upright posture.

(10) In the above embodiment, the opening section35is formed in the inner lateral surface24B of the extended ridge section24, and the driver unit51is fixed such that the cooling surface51cfaces the recessed space24athrough the opening section35. However, the disclosure is not limited to such a configuration, and a configuration may be adopted in which the opening section35is not formed in the inner lateral surface24B of the extended ridge section24. In such a case, the driver unit51may be fixed such that the cooling surface51cis in intimate contact with the inner lateral surface24B of the extended ridge section24, and the driver unit51may be cooled via the inner lateral surface24B of the extended ridge section24.

(11) In the above embodiment, a configuration in which the recessed space24aand the wheel housing space23aare integrally formed continuously in the front-back direction X is described as an example. However, the disclosure is not limited to such a configuration, and the recessed space24aand the wheel housing space23amay be formed independently of each other discontinuously. In such a case, the air passageway30is constituted by a space from the lower opening31to the recessed space24avia the diameter expansion section32, and does not include the wheel housing space23a.

(12) In the above embodiment, a configuration in which travel-generated wind flowing through the air passageway30reaches the recessed space24afrom the lower opening31via the diameter expansion section32, and further passes through to the wheel housing space23a,assuming that the article transport vehicle1is moving forward, is described as an example. However, the disclosure is not limited to such a configuration, and the article transport vehicle1may travel in reverse. In such a case, travel-generated wind flowing through the air passageway30will reach the recessed space24afrom the wheel housing space23a,and further pass through to the lower opening31via the diameter expansion section32.

(13) In the above embodiment, the article transport vehicle1may include a configuration (flow promoting section) for promoting the flow of travel-generated wind through the air passageway30. Examples of such a flow promoting section include an impeller that rotates as one with the wheels.

(14) The configurations disclosed in each of the above-described embodiments (including the above embodiment and other embodiments; this similar applies below) can also be applied in combination with configurations disclosed in other embodiments as long as no inconsistencies arise. With respect also to other configurations, the embodiments disclosed herein are exemplary in all respects and can be modified as appropriate without departing from the spirit of the disclosure.

Summary of the Embodiments

In summarizing the above, the article transport vehicle according to the present disclosure preferably includes the following configurations.

An article transport vehicle for transporting an article, including:a body;a wheel held by the body;a motor configured to drive the wheel; anda driver unit configured to control the motor,wherein the driver unit is disposed to extend vertically and in a front-back direction of the body,in the driver unit, at least one surface facing in a width direction orthogonal to the front-back direction as viewed in an up-down direction is a cooling surface, andthe body is provided, in a bottom section thereof, with an air guide path configured to guide travel-generated wind to the cooling surface.

According to this configuration, disposing the driver unit to extend in the front-back direction of the body in an upright posture facilitates both securing a large internal space in the body and downsizing of the article transport vehicle as a whole. Given that the surfaces of the driver unit disposed in an upright posture to extend in the front-back direction of the body that face in the width direction have the largest area, cooling efficiency can be enhanced by using at least one of these surfaces as the cooling surface. Furthermore, the driver unit can be cooled more efficiently, by directing travel-generated wind through the air guide path to the cooling surface, when the article transport vehicle is travelling. These factors enable an article transport vehicle to be realized that is readily downsized as a whole and is able to efficiently cool the driver unit.

As one mode, preferably the body has a recessed space recessed upward from a bottom surface, andthe air guide path includes the recessed space.

According to this configuration, an air guide path that guides travel-generated wind to the cooling surface of the driver unit disposed in an upright posture can be appropriately constituted, by forming a recessed space that is recessed upward from the bottom surface in the body and utilizing this recessed space.

As one mode, preferably the body has an opening section communicating with the recessed space, andthe driver unit is disposed in such a manner that the cooling surface faces the recessed space through the opening section.

According to this configuration, the driver unit can be efficiently cooled, by travel-generated wind directed to the recessed space from the opening section formed in the body.

As one mode, preferably the wheel is disposed in a wheel housing space recessed upward from the bottom surface in the bottom section of the body, andthe recessed space and the wheel housing space are continuous in the front-back direction.

According to this configuration, the recessed space constituting the air guide path can be appropriately formed, by utilizing the wheel housing space that is recessed upward from the bottom surface of the body. Accordingly, further downsizing of the article transport vehicle can be achieved.

As one mode, preferably the driver unit has a rectangular parallelepiped shape.

According to this configuration, the installation density of the driver unit itself can be enhanced, and an even larger internal space can be secured in the body. Therefore, it is possible to realize an article transport vehicle that is even more readily downsized as the whole.

The article transport vehicle according to the present disclosure need only achieve at least one of the above-described effects.