Work vehicle

Abstract

To arrange a duct used for cooling of a device etc. according to a vehicle configuration when a work vehicle capable of changing a vehicle shape is formed.SOLUTION: A work vehicle 1 includes a duct 42 which may extend or contract according to a change of a vehicle shape and further includes a first portion and a second portion which are linked so as to be movable relative to each other. The duct 42 extends over the first portion and the second portion and has extensible parts 42c, 42d, 42e which may extend or contract in response to relative movement between the first portion and the second portion. One of the first portion and the second portion is a vehicle body 2 and the other is traveling structures 3 which are disposed at left and right sides of the vehicle body 2.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present invention relates to a work vehicle for performing work such as agricultural work.

Background Art

[0002] In recent years, regarding agricultural work and the like using work vehicles, the work form has shifted from a manual operation form in which an operator gets into the vehicle to a remote control type work form in which the operator remotely controls the vehicle using a terminal device or the like, or an autonomous driving type work form in which the vehicle is driven along a route set in the field by GPS. That is, the work form is shifting to a form in which the work vehicle runs unmanned.

[0003] Therefore, regarding the form of the vehicle as well, it is conceivable to change from the conventional tractor type equipped with a driver's seat to a more convenient form for performing the intended work such as agricultural work. For example, using an unmanned work vehicle composed of a vehicle body and left and right traveling structures having wheels and the like arranged on both left and right sides of the vehicle body, the vehicle body is arranged in a state of being bridged over ridges, and the left and right traveling structures are arranged on both left and right sides of the ridges to perform agricultural work.

[0004] Further, in such a work vehicle, it is conceivable to configure the vehicle shape to be changeable, such that the width of the vehicle body can be changed according to the width of the ridge, and the vehicle body can be moved up and down according to the height of the crops growing on the ridge. On the other hand, it is also conceivable to pipe ducts and the like for cooling equipment provided at various parts of such a work vehicle.

[0005] Here, for example, Patent Document 1 discloses a duct having a telescopic bellows portion, and Patent Documents 2 and 3 disclose embodiments in which a duct having a structure with such a telescopic portion is applied to a vehicle.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

[0007] In the driverless work vehicle having the configuration as described above, when providing a circuit for equipment cooling, it is required to provide a duct having a structure corresponding to a change in the vehicle shape. The embodiments shown in Patent Documents 2 and 3 described above correspond to a seat that can move back and forth with respect to the vehicle body, and do not correspond to a change in the vehicle shape. [Means for Solving the Problems]

[0008] The work vehicle according to an embodiment of the present invention includes a duct that can expand and contract corresponding to a change in the vehicle shape.

[0009] The work vehicle includes a first part and a second part that are linked to be relatively movable with respect to each other, and the duct extends across the first part and the second part, and may have an expansion and contraction part that can expand and contract according to the relative movement between the first part and the second part.

[0010] One of the first part and the second part is the vehicle body, and the other may be a traveling structure disposed on the left and right sides of the vehicle body.

[0011] The vehicle body is movable in the vertical direction with respect to the traveling structure, and the duct may have the expansion and contraction part in a vertical part disposed between the vehicle body and the traveling structure.

[0012] ​The work vehicle includes a cooling device provided on the vehicle body and a device to be cooled provided on the traveling structure and cooled by a cooling medium supplied from the cooling device. The duct may extend between the cooling device and the device to be cooled as a passage for the cooling medium.

[0013] One of the first part and the second part is a first part of the vehicle body, and the other is a second part of the vehicle body. The duct may have the telescopic part at a portion disposed between the first part and the second part of the vehicle body.

[0014] The first part and the second part of the vehicle body are relatively movable in the front-rear direction. The duct may have the telescopic part at a front-rear direction portion disposed between the first part and the second part of the vehicle body.

[0015] The first part and the second part of the vehicle body are relatively movable in the left-right direction. The duct may have the telescopic part at a left-right direction portion disposed between the first part and the second part of the vehicle body.

[0016] The work vehicle includes a traveling structure provided on a side of the vehicle body, the vehicle body is relatively movable with respect to the traveling structure, and the duct may be provided with a plurality of the telescopic parts at a portion disposed between the first part and the second part of the vehicle body and at a portion disposed between the vehicle body and the traveling structure.

[0017] The work vehicle includes a cooling device provided on the first part or the second part of the vehicle body and a device to be cooled provided on the traveling structure and cooled by a cooling medium supplied from the cooling device. The duct may extend between the cooling device and the device to be cooled as a passage for the cooling medium.

[0018] The vehicle body has a third part that is relatively movable with respect to the second part, and the duct may be provided with the plurality of telescopic parts in a part disposed between the first part and the second part of the vehicle body and in a part disposed between the second part and the third part of the vehicle body.

[0019] The first part and the second part of the vehicle body are relatively movable in the front-rear direction, the second part and the third part of the vehicle body are relatively movable in the left-right direction, and the duct may be provided with the plurality of telescopic parts in a front-rear direction part disposed between the first part and the second part of the vehicle body and in a left-right direction part disposed between the second part and the third part of the vehicle body.

[0020] The work vehicle includes a traveling structure provided on the side of the vehicle body, a cooling device provided on the first part of the vehicle body, and a device to be cooled that is disposed on the traveling structure and cooled by a cooling medium supplied from the cooling device. The duct extends in the front-rear direction from the cooling device to the second part of the vehicle body, bends at the second part of the vehicle body, extends in the left-right direction from the second part to the third part, and may extend in the vertical direction from the third part of the vehicle body to the device to be cooled.

Advantages of the Invention

[0021] According to the present invention, even in a work vehicle with a special structure in which the vehicle shape changes, when the shape changes, the duct expands and contracts, so that the connection between devices by the duct can be maintained.

Brief Description of the Drawings

[0022]

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Embodiments for Carrying Out the Invention

[0023] Hereinafter, a preferred embodiment of the work vehicle 1 according to the present invention will be described. FIGS. 1 to 14 are diagrams showing an embodiment (first embodiment) of the work vehicle 1. FIG. 1 is a perspective view of the work vehicle 1. FIG. 2 is a plan view of the work vehicle 1. FIG. 3 is a left side view of the work vehicle 1. FIG. 4 is a right side view of the work vehicle 1. FIG. 5 is a front view of the work vehicle 1. FIG. 6 is a rear view of the work vehicle 1. FIG. 7 is a side sectional view of the work vehicle 1.

[0024] FIG. 8 is a perspective view of the work vehicle 1 with the vehicle body 2 raised. FIG. 9 is a plan view of the work vehicle 1 with the right part of the vehicle body 2 expanded. FIG. 10 is a schematic diagram showing the structure of the center battery case 24. FIG. 11 is a schematic diagram showing the structure of the side battery case 36. FIG. 12 is a block diagram showing the water cooling circuit R1 in the vehicle body 2. FIG. 13 is a block diagram showing the water cooling circuit R2 in the traveling structure 3. FIG. 14 is a block diagram showing the control system structure of the work vehicle 1.

[0025] In the following description, the direction pointed by the arrow X1 in FIG. 1 is the front, the direction pointed by the arrow X2 is the rear, the direction pointed by the arrow Y1 is the left, the direction pointed by the arrow Y2 is the right, the direction pointed by the arrow Z1 is the upper, and the direction pointed by the arrow Z2 is the lower.

[0026] Examples of the work performed by the work vehicle 1 include, but are not limited to, work related to agriculture, work related to industry (such as civil engineering and construction), work related to transportation, etc. In the case of a preferred embodiment of the present invention, the work performed by the work vehicle 1 is work related to agriculture (farming work). Hereinafter, the case where the work performed by the work vehicle 1 is farming work will be described as an example. In this case, the work vehicle 1 is an agricultural work vehicle.

[0027] With reference to FIGS. 1 to 7, FIG. 14, etc., the basic structure of the work vehicle 1 will be described. The work vehicle 1 includes a vehicle body 2, a left traveling structure 3L disposed on the left side of the vehicle body 2, and a right traveling structure 3R disposed on the right side of the vehicle body 2. Hereinafter, each of the left traveling structure 3L and the right traveling structure 3R may be referred to as a traveling structure 3.

[0028] The vehicle body 2 is provided with a PTO shaft 65 (see FIG. 14) for transmitting driving force to a work device (implement) connected to the work vehicle 1 at its rear end portion or the like, and a connection device 60 (see FIG. 14) for connecting the work device to the work vehicle 1 can be mounted.

[0029] Regarding the structure of the connection device 60, various structures can be considered according to the type of the work device (implement) and the like. A typical structure is a three-point link mechanism having a pair of left and right lower links and one top link.

[0030] Note that the work device can also be connected to a portion other than the rear end portion (for example, the front end portion) of the vehicle body 2 of the work vehicle 1 and receive driving force from the work vehicle 1. Alternatively, the work vehicle 1 may be provided without a connection device and may include a work device in a state of being mounted on the vehicle body 2, for example.

[0031] The configuration of the vehicle body 2 disposed between the left traveling structure 3L and the right traveling structure 3R and various devices provided on the vehicle body 2 will be described.

[0032] The vehicle body 2 has a vehicle body frame structure 20, a center battery case (front main body case) 24 supported by the vehicle body frame structure 20, and a PTO case (rear main body case) 26.

[0033] The vehicle body frame structure 20 has a vehicle body center frame 21, a left vehicle body side frame 22L disposed on the left side of the vehicle body center frame 21, and a right vehicle body side frame 22R disposed on the right side of the vehicle body center frame 21. Hereinafter, each of the left vehicle body side frame 22L and the right vehicle body side frame 22R may be referred to as the vehicle body side frame 22.

[0034] A flat plate-shaped support member 23 (see FIG. 2 etc.) is fixedly provided at the lower part of the portion from the front end to the middle part in the front-rear direction of the vehicle body center frame 21, and a rectangular parallelepiped center battery case 24 is suspended from the support member 23. The upper end portion of the center battery case 24 is engaged with the support member 23 so as to be movable in the front-rear direction.

[0035] A situation detection device 10 and a positioning device 11 for detecting the situation around the work vehicle 1 (such as the presence or absence of obstacles, the growth degree of crops growing in the ridges, the width of the ridges, etc.) are provided on the upper part of the support member 23 or the vehicle body center frame 21.

[0036] In the present embodiment shown in FIGS. 1 to 6, as will be described later, since the extension portions 43a of the ducts 43L and 43R are spanned on the vehicle body center frame 21, as shown in FIG. 1 etc., a stay 10d straddling these is provided on the vehicle body center frame 21, and the situation detection device 10 and the positioning device 11 are provided on the stay 10d.

[0037] The situation detection device 10 and the positioning device 11 may be provided on the vehicle body 2 (vehicle body center frame 21) without interfering with ducts or the like, and the attachment structure to the vehicle body 2 is not limited.

[0038] ​For example, in another embodiment (the second embodiment) described later and shown in FIG. 16, since there are no extension portions 43a of the ducts 43L and 43R on the vehicle body center frame 21, the situation detection device 10 is directly attached to a support member 23 provided immediately below the upper part of the vehicle body center frame 21 without passing through the stay 10d.

[0039] Each vehicle body side frame 22 is connected to the vehicle body center frame 21 so as to be relatively movable in the left - right direction. On the upper part of the vehicle body center frame 21, a pair of width - changing cylinders 8A and 8B extending in the left - right direction are provided as a vehicle body deforming device (actuator) 80 (see FIG. 14) for changing the left - right width of the vehicle body 2, that is, for deforming the vehicle body 2. Hereinafter, each of the pair of width - changing cylinders 8A and 8B may be referred to as a width - changing cylinder 8.

[0040] The width - changing cylinder 8A expands and contracts to change the distance between the vehicle body center frame 21 and the left vehicle body side frame 22L. The cylinder body of the width - changing cylinder 8A is attached to the upper part of the vehicle body center frame 21, the piston rod extends leftward from the cylinder body, and the tip of the piston rod is attached to the upper part of the left vehicle body side frame 22L.

[0041] The width - changing cylinder 8B expands and contracts to change the distance between the vehicle body center frame 21 and the right vehicle body side frame 22R. The cylinder body of the width - changing cylinder 8B is attached to the upper part of the vehicle body center frame 21 in front of or behind (in this embodiment, in front of) the cylinder body of the width - changing cylinder 8A. The piston rod extends rightward from the cylinder body, and the tip of the piston rod is attached to the upper part of the right vehicle body side frame 22R.

[0042] In this way, by the expansion and contraction movement of each width - changing cylinder 8, the vehicle body side frame 22 moves forward and backward with respect to the vehicle body center frame 21, and the left - right width of the vehicle body 2 is changed as described above, and the vehicle body 2 is deformed.

[0043] For example, as shown in FIG. 9, by extending the piston rod of the width-changing cylinder 8B, the right body side frame 22R moves away from the body center frame 21 to the right, and the body 2 deforms such that the right part of the body 2 expands.

[0044] Along with this, the right traveling structure 3R connected to the right body side frame 22R also moves to the right together with the right body side frame 22R, and the lateral distance between the left traveling structure 3L and the right traveling structure 3R, and thus the vehicle width, which is the distance between the left and right wheels 5 corresponding thereto, increases.

[0045] On the other hand, referring to FIG. 9, if the piston rod of the width-changing cylinder 8A is extended, the left body side frame 22L and the left traveling structure 3L move away from the body center frame 21 to the left, and the body 2 deforms such that the left part of the body 2 expands. Also by this, the vehicle width can be changed.

[0046] Regarding the deformation of the body 2 in the direction of expanding the vehicle width, both the width-changing cylinders 8A and 8B may be extended or contracted to move both the left and right body side frames 22L and 22R. Also, the expansion and contraction movements of the width-changing cylinders 8A and 8B may be synchronized.

[0047] Note that the width-changing cylinder 8 as the body deformation device for changing the left and right width of the body 2 may be a cylinder of any structure as long as it functions as the body deformation device 80, such as a hydraulic cylinder, an air cylinder, an electric cylinder, etc.

[0048] Also, as long as the body deformation device 80 has a function of changing the left and right width of the body 2, it does not necessarily have a structure having a cylinder such as the width-changing cylinder 8. For example, it may have a structure in which a screw rod is rotated by a motor to move the body side frame 22 forward and backward with respect to the body center frame 21.

[0049] As for the entire vehicle body 2, the left vehicle body side frame 22L of the vehicle body frame structure 20 is connected to the left traveling frame 30L of the left traveling structure 3L, and the right vehicle body side frame 22R is connected to the right traveling frame 30R of the right traveling structure 3R via a plurality of mast structures 31 (see FIG. 1 etc.) arranged between the vehicle body 2 (each vehicle body side frame 22) and each traveling structure 3 (each traveling frame 30) so as to be relatively vertically movable. Thus, the vehicle body 2 can move (lift) vertically with respect to the left and right traveling structures 3.

[0050] As shown in FIGS. 2, 6 etc., the work vehicle 1 is provided with a pair of left and right vehicle body lifting cylinders 9, that is, a left vehicle body lifting cylinder 9L and a right vehicle body lifting cylinder 9R, as an actuator (hydraulic actuator) for lifting the vehicle body 2, that is, as a vehicle body moving device 90 (see FIG. 14) for relatively moving the vehicle body 2 with respect to the left and right traveling structures 3.

[0051] The cylinder bottom, which is the upper end of each vehicle body lifting cylinder 9 (left vehicle body lifting cylinder 9L, right vehicle body lifting cylinder 9R), is connected to the upper part of the vehicle body side frame 22 (left vehicle body side frame 22L, right vehicle body side frame 22R). On the other hand, the piston rod head, which is the lower end of each vehicle body lifting cylinder 9, is supported by a bracket or the like that protrudes inward of the vehicle from the inner side end of the traveling frame 30 (left traveling frame 30L, right traveling frame 30R) inside the vehicle.

[0052] Normally, the piston rods of the left vehicle body lifting cylinder 9L and the right vehicle body lifting cylinder 9R are contracted, and the vehicle body 2 is arranged at the lowest position in its vertical movement range as shown in FIGS. 1, 3 to 6 etc. When the left vehicle body lifting cylinder 9L and the right vehicle body lifting cylinder 9R simultaneously extend the piston rods with the same stroke, as shown in FIG. 8, the entire vehicle body 2 rises. Specifically, due to the extension movement of the piston rods of the left vehicle body lifting cylinder 9L and the right vehicle body lifting cylinder 9R, the vehicle body 2 moves upward with respect to the left and right traveling structures 3 while being guided by the mast structure 31.

[0053] Incidentally, it is also conceivable to adjust the left - right inclination of the vehicle body 2 by differentially expanding and contracting the left vehicle - body lifting cylinder 9L and the right vehicle - body lifting cylinder 9R. For example, when the left - hand traveling structure 3L becomes lower than the right - hand traveling structure 3R due to the inclination of the ground to the lower - left, and the vehicle body 2 inclines to the lower - left, it is conceivable to extend only the left vehicle - body lifting cylinder 9L, and move the left part of the vehicle body 2 relatively upward with respect to the left - hand traveling structure 3L, thereby horizontally holding the vehicle body 2 in the left - right direction.

[0054] Incidentally, the vehicle - body lifting cylinders 9 do not necessarily have to be a pair on the left and right, and are not limited in terms of quantity or the position within the vehicle body 2. Also, as an actuator for moving the vehicle body 2 in the up - down direction, it does not have to be a telescopic actuator such as the vehicle - body lifting cylinder 9. For example, it may be configured to move the vehicle body 2 in the up - down direction by the rotation of an electric motor.

[0055] Incidentally, in the present embodiment, as described above, the width - changing cylinder 8 which is the vehicle - body deformation device 80 and the vehicle - body lifting cylinder 9 which is the vehicle - body moving device 90 are hydraulic actuators. As shown in FIG. 14, the expansion and contraction movements are controlled by the control device 15 controlling the respective control valves in the control valve unit 27.

[0056] Incidentally, the width - changing cylinder 8 and the vehicle - body lifting cylinder 9 described in FIG. 14 respectively mean each of the width - changing cylinders 8A, 8B and each of the vehicle - body lifting cylinders 9L, 9R, and the control device 15 can control these expansion and contraction movements individually.

[0057] As shown in FIGS. 2, 5, 7, etc., a battery (center battery) 50 is housed in the center battery case 24. Considering the weight balance of the entire work vehicle 1 with the heavy center battery 50, or for other reasons (for example, in relation to the layout of the equipment in the vehicle body 2), the center battery case 24 is movable relative to the vehicle body center frame 21 (vehicle body frame structure 20) in the front-rear direction. That is, the vehicle body 2 also deforms when the center battery case 24 moves back and forth relative to the vehicle body center frame 21.

[0058] In order to move the center battery case 24 back and forth relative to the vehicle body center frame 21, for example, a battery moving actuator 81, which is a hydraulic cylinder, may be provided as a vehicle body deforming device 80 (see FIG. 14). Alternatively, without providing such a vehicle body deforming device, an operator may directly push or pull the center battery case 24 by hand to move it back and forth relative to the vehicle body center frame 21.

[0059] An air conditioner unit (air temperature adjusting device) 51 is provided in front of the center battery case 24, and a radiator 52 is provided immediately in front of the air conditioner unit 51. The radiator 52 is arranged at the front end of the vehicle body 2, and nothing is arranged in front of the radiator 52 in the vehicle body 2. The front surface of the radiator 52 is not shielded by other members, and the radiator 52 can efficiently take in outside air and improve the heat exchange efficiency. A radiator fan 52a is provided at the rear of the radiator 52. That is, an air cooling device and a water cooling device are provided immediately in front of the center battery case 24.

[0060] The air conditioner unit 51 and the radiator fan 52a can be operated with the electric power supplied from the center battery 50 and / or the side battery 37, and as shown in FIG. 14, the output is controlled by the control device 15 based on the detection result of, for example, the temperature detection device 18 provided in the work vehicle 1.

[0061] As shown in FIG. 10, the center battery case 24 is connected to the air conditioner unit 51 without passing through a duct, and the cooling air discharged from the air conditioner unit 51 is introduced into the center battery case 24 to cool the center battery 50, and the cooling air after cooling the center battery 50 is configured to return to the air conditioner unit 51. The structure of this center battery case 24 will be described in detail later in relation to the piping of the duct between the air conditioner unit 51 and the side battery case 36 described later.

[0062] As shown in FIG. 7 and the like, at the rear of the center battery case 24, the PTO case 26 is supported by the vehicle body center frame 21. A PTO shaft 65 (see FIG. 14) for transmitting power to a working device connected to the PTO case 26 and the like is pivotally supported on the PTO case 26, and protrudes rearward, for example, from the rear end of the PTO case 26 as the rear end of the vehicle body 2.

[0063] Inside or outside the PTO case 26, a working system electric unit E1 and a hydraulic system electric unit E2 as electrical equipment shown in FIG. 12 are provided. The working system electric unit E1 is an electric component unit for driving and controlling the PTO shaft 65, and has an electric motor 54 as a working system prime mover and an inverter 53 for controlling the output of the electric motor 54.

[0064] The hydraulic system electric unit E2 is an electric component unit for driving and controlling a hydraulic pump 57 for supplying hydraulic oil to hydraulic actuators provided in the work vehicle 1, including the aforementioned width change cylinder 8 and vehicle body lift cylinder 9 provided in the vehicle body 2, the lift cylinder 61 and attitude adjustment cylinder 63 (see FIG. 14) provided in the connecting device 60, and the steering cylinder 35 provided in the traveling structure 3. It has an electric motor 56 as a hydraulic system prime mover and an inverter 55 (see FIG. 12) for controlling the output of the electric motor 56.

[0065] ​As shown in FIGS. 6 and 7, the electric motor 56 and the inverter 55 as the hydraulic system electric unit E2 are arranged below the PTO case 26, and the hydraulic pump 57 is connected to the electric motor 56.

[0066] The electric motor 54 of the working system electric unit E1 obtains power from the center battery 50 and / or the side battery 37 and is driven, and drives the PTO shaft 65 with its output. The inverter 53 converts the direct current from the center battery 50 into an alternating current, and applies the alternating current to the electric motor 54 at a set voltage and / or frequency.

[0067] As shown in FIG. 14, by controlling the set values of the voltage and / or frequency of the inverter 53 by the control device 15, the output rotational speed and / or torque of the electric motor 54 are controlled, whereby the rotational speed and / or torque of the PTO shaft 65 are controlled.

[0068] Note that a transmission mechanism for transmitting the output of the electric motor 54 to the PTO shaft 65 may be provided in the PTO case 26. This transmission mechanism may have gears, endless belts, or other structures. Further, this transmission mechanism may be a stepped or stepless speed change mechanism. Furthermore, a clutch, a braking device, etc. may be provided in this transmission mechanism.

[0069] The electric motor 56 of the hydraulic system electric unit E2 obtains power from the center battery 50 and / or the side battery 37 and is driven, and drives the hydraulic pump 57 with its output. The inverter 55 converts the direct current from the center battery 50 into an alternating current, and applies the alternating current to the electric motor 56 at a set voltage and / or frequency.

[0070] As shown in FIG. 14, by controlling the set values of the voltage and / or frequency of the inverter 55 by the control device 15, the output rotational speed and / or torque of the electric motor 56 are controlled, whereby the rotational speed and / or torque of the hydraulic pump 57 are controlled.

[0071] Assuming that the connecting device 60 is a three-point link mechanism, the left and right lower links of the connecting device 60 are connected to the left and right lift arms. As the left and right lift cylinders 61 expand and contract, the left and right lift arms move up and down, and the left and right lower links move up and down following the movement of the left and right lift arms. As a result, the working device mounted on the left and right lower links and the top link of the connecting device 60 moves up and down (lifts and lowers).

[0072] Also, by adjusting the difference between the distance between the left lift arm and the left lower link and the distance between the right lift arm and the right lower link by the expansion and contraction of the posture adjustment cylinder 63, the inclination angle of the working device mounted on the connecting device 60 in the left-right direction is adjusted.

[0073] With this configuration, for example, even if the working device during agricultural work is about to tilt left and right due to the slope of the field, by adjusting the distance between the lift arm and the lower link by the expansion and contraction of the posture adjustment cylinder 63, the working device is maintained in a horizontal state in the left-right direction. For example, in the working track of a working device such as a ridging device a good ridge without inclination in the left-right direction can be formed.

[0074] As described above, the connecting device 60 mounted on the PTO case 26 etc. can connect a working device. Further, the working device connected to the vehicle body 2 via the connecting device 60 can receive a driving force from the PTO shaft 65 (see FIG. 14) protruding from the PTO case 26.

[0075] Examples of the working device include devices for performing agricultural work, devices for performing civil engineering work, devices for performing construction work, and devices for performing transportation-related work, etc., but are not limited to these working devices. In the case of the embodiment shown below, the working device is a device for performing agricultural work.

[0076] Examples of work devices for performing agricultural work include a spraying device for spraying substances such as fertilizers and chemicals, a seeding device for sowing seeds, a tilling device for tilling the soil, a plowing device (plow) for plowing the soil, a weeding device for weeding, a soil heaping device for heaping soil, etc. However, the work device only needs to be a device for performing agricultural work, and its type is not particularly limited.

[0077] When the work device is an electric work device, instead of being driven by the power taken out from the PTO shaft 65, it may be driven by the power taken out to the outside of the vehicle body 2 via a power line from the center battery 50 and / or the side battery 37.

[0078] The work device may be connected to the work vehicle 1 while being arranged on the side or front of the vehicle body. Also, for example, when the work device is arranged in front of the work vehicle 1, the connecting device 60 may be mounted on, for example, the center battery case 24, and the work device arranged in front of the work vehicle 1 through the connecting device 60 thus mounted on the front part of the vehicle body 2 may be connected to the work vehicle 1.

[0079] In addition to or instead of the PTO shaft 65 provided at the rear part of the vehicle body 2, for example, a front PTO shaft may be provided forward from the center battery case 24, and the work device in front of the work vehicle 1 may be driven by the front PTO shaft. Examples of such a front-mounted type work device for agricultural work (implement) include a combine unit formed by combining a harvesting unit, a threshing unit, a sorting unit, etc. of a combine.

[0080] Also, the connecting device 60 may be detachable from the PTO case 26 or the like. It is also conceivable to provide an attachment part on a part of the vehicle body 2 other than the PTO case 26, for example, the center battery case 24, so that the work device can be connected to the work vehicle 1 in front of the vehicle body 2.

[0081] Furthermore, the working device may be mounted on the upper part of the vehicle body frame structure 20 in the vehicle body 2 of the work vehicle 1, for example, without passing through the connecting device 60. In this case, a PTO shaft for transmitting driving force to the working device may be provided so as to project upward from the upper part of the vehicle body frame structure 20 (for example, the vehicle body center frame 21).

[0082] The work vehicle 1 includes hydraulic actuators such as the width change cylinder 8 provided on the vehicle body 2, the vehicle body lift cylinder 9, and the steering cylinder 35 provided on the traveling structure 3 as described above. In some cases, the connecting device 60 attached to the vehicle body 2 may also include hydraulic actuators such as the lift cylinder 61 and the attitude adjustment cylinder 63 described above.

[0083] For the operation control of these hydraulic actuators, one or more control valve units 27 are attached to the outside of the PTO case 26 or the like. Each control valve unit 27 incorporates a control valve for controlling the flow of hydraulic oil between the hydraulic pump 57 and the hydraulic actuator to be hydraulically controlled respectively, and also has ports for fluidly connecting the control valve to the hydraulic pump 57, the hydraulic actuator, etc. via oil pipes or the like. It has a control valve, and also has ports for fluidly connecting the control valve to the hydraulic pump 57, the hydraulic actuator, etc. via oil pipes or the like.

[0084] Note that one control valve unit 27 may be configured by combining control valves for different hydraulic actuators to be hydraulically controlled. Also, not only outside the PTO case 26 as described above, but a control valve may be provided inside the PTO case 26.

[0085] Furthermore, when the control valve of the control valve unit 27 is an electromagnetic valve or the like, the control valve unit 27 may be electrically connected to the control device 15 or the like by an electric wire or the like.

[0086] Note that instead of the battery 50, an internal combustion engine (engine) may be arranged inside the center battery case 24 or the like, and the hydraulic pump 57 for operating the above-described hydraulic actuator may be driven by the engine output, and the PTO shaft 65 may be driven by transmitting the engine output to the PTO shaft 65.

[0087] As described above, the vehicle body 2 can be "deformed" by the center battery case 24 moving in the front-rear direction with respect to the vehicle body center frame 21 and each of the left and right vehicle body side frames 22 moving in the left-right direction with respect to the vehicle body center frame 21. The width change cylinder 8 functions as a vehicle body deformation device (actuator) for deforming the vehicle body 2.

[0088] Also, the vehicle body 2 can "move" in the vertical direction relative to the left and right traveling structures 3L and 3R. The vehicle body lifting cylinder 9 functions as a vehicle body moving device (actuator) for moving the vehicle body 2.

[0089] As described above, by the vehicle body 2 itself deforming or the entire vehicle body 2 moving vertically relative to the left and right traveling structures 3L and 3R, the shape of the work vehicle 1 composed of the vehicle body 2 and the left and right traveling structures 3L and 3R changes. The shape of this work vehicle 1 shall be referred to as the "vehicle shape".

[0090] As shown in FIG. 14, the vehicle body deformation device 80 including the width change cylinder 8, the battery moving actuator 81, etc., and the vehicle body moving device 90 including the vehicle body lifting cylinder 9, etc., are collectively referred to as the vehicle shape changing device 100. The control device 15 controls each device included in the vehicle shape changing device 100.

[0091] As described above, in addition to the width change cylinder 8, the battery moving actuator 81, and the vehicle body lifting cylinder 9 included in the vehicle shape changing device 100, the lift cylinder 61, the attitude adjustment cylinder 63, etc. included in the connecting device 60 are all hydraulic actuators and are actuated by the hydraulic oil discharged by the hydraulic pump 57 driven by the electric motor 56 of the hydraulic system electric unit E2.

[0092] Now, as described above, in the front part of the vehicle body 2, in front of the center battery case 24, the air conditioner unit 51 included in the air cooling device 110 (see FIG. 14) and the radiator 52 (with a radiator fan 52a) included in the water cooling device 120 (see FIG. 14) are arranged. Among these, the structure of the cooling air circulation circuit (duct) from the air conditioner unit 51 will be described in detail later. Here, the structure of the circulation circuit of the cooling water cooled by the radiator 52, which is configured within the vehicle body 2, will be described with reference to FIGS. 1 to 8, FIG. 12, and FIG. 13.

[0093] At the front part of the vehicle body 2, the radiator 52 is arranged so as to extend in the left - right direction and the up - down direction. The air generated by the rotation of the radiator fan 52a arranged immediately behind the radiator 52 is blown onto the radiator 52, and it is configured to promote heat exchange (cooling) in the radiator 52.

[0094] In the space within the vehicle body 2, behind the radiator 52 and below the air conditioner unit 51, a pair of electric cooling water pumps 58A, 58B, and a reservoir tank 59 (see FIGS. 5, 7, etc.) are provided.

[0095] The electric cooling water pump 58A sucks the cooling water from the reservoir tank 59 and supplies it to the inverter 53 and the electric motor 54 of the working system electric unit E1 to cool them. The electric cooling water pump 58B sucks the cooling water from the reservoir tank 59 and supplies it to the inverter 55 and the electric motor 56 of the hydraulic system electric unit E2 to cool them.

[0096] Note that either of the pair of electric cooling water pumps 58 shown in FIG. 5 etc. can be used as the electric cooling water pump 58A for the working system electric unit E1, and either can be used as the electric cooling water pump 58B for the hydraulic system electric unit E2.

[0097] The radiator 52 is a cooling device (air-cooling device) that cools the cooling water discharged from the electric cooling water pumps 58A and 58B and circulated in the traveling structure 3. The radiator fan 52a is driven by obtaining power from the center battery 50 and / or the side battery 37, and promotes the heat exchange of the cooling water in the radiator 52.

[0098] Thus, as shown in FIG. 12, a water-cooled cooling (temperature adjustment) circuit R1 is configured in the vehicle body 2 to provide a cooling water passage for circulating the cooling water among the radiator 52 (radiator fan 52a), the electric cooling water pumps 58A and 58B, the working system electric unit E1, the hydraulic system electric unit E2, and the like.

[0099] That is, the water-cooled cooling (temperature adjustment) circuit R1 includes, as a parallel circuit, a circuit for supplying cooling water to the working system electric unit E1 (such as the electric motor 54) and a circuit for supplying cooling water to the hydraulic system electric unit E2 (such as the electric motor 56). The electric cooling water pumps 58A and 58B are provided as pumps that individually discharge the cooling water into their respective cooling water supply circuits. Therefore, the cooling water can be efficiently supplied to each cooling target device (that is, each of the working system electric unit E1 and the hydraulic system electric unit E2), and the flow of each cooling water can be individually controlled.

[0100] Next, the structure of the traveling structure 3 will be described. Each traveling structure 3 has a traveling frame 30 and a pair of wheel units 4. The pair of wheel units 4 includes a front wheel unit 4F supported at the front part of the traveling frame 30 and a rear wheel unit 4R supported at the rear part of the traveling frame 30.

[0101] Each wheel unit 4 has one wheel 5 and a wheel drive case 32 that supports the axle 5a, which is the central axis of the wheel 5. The wheel 5 of the front wheel unit 4F is the front wheel 5F, and the wheel 5 of the rear wheel unit 4R is the rear wheel 5R.

[0102] Incidentally, the front wheels 5F and the rear wheels 5R have substantially the same diameter. Alternatively, the front wheels 5F and the rear wheels 5R may have different diameters. Further, at least one of the front wheels 5F and the rear wheels 5R may be a drive wheel (drive sprocket) of the crawler-type traveling device.

[0103] Furthermore, the traveling frame 30 of the left traveling structure 3L is the left traveling frame 30L. The front wheel unit 4F supported at the front portion of the left traveling frame 30L is the left front wheel unit 4FL having the left front wheel 5FL. The rear wheel unit 4R supported at the rear portion of the left traveling frame 30L is the left rear wheel unit 4RL that pivotally supports the left rear wheel 5RL.

[0104] On the other hand, the traveling frame 30 of the right traveling structure 3R is the right traveling frame 30R. The front wheel unit 4F supported at the front portion of the right traveling frame 30R is the right front wheel unit 4FR that pivotally supports the right front wheel 5FR. The rear wheel unit 4R supported at the rear portion of the right traveling frame 30R is the right rear wheel unit 4RR that pivotally supports the right rear wheel 5RR. On the other hand, the traveling frame 30 of the right traveling structure 3R is the right traveling frame 30R, and the front wheel unit 4F supported at the front part of the right traveling frame 30R is the right front wheel unit 4FR that pivotally supports the right front wheel 5FR, and the rear wheel unit 4R supported at the rear part of the right traveling frame 30R is the right rear wheel unit 4RR that pivotally supports the right rear wheel 5RR.

[0105] On the upper part of the wheel drive case 32 of each wheel unit 4, a traveling motor 7 and a gear mechanism or the like for transmitting the output of the traveling motor 7 are housed. From the upper part, a rotating cylinder portion 32a shown in FIGS. 5, 6, etc. extends vertically downward. The rotating cylinder portion 32a is connected to the upper part of the wheel drive case 32 so as to be relatively rotatable.

[0106] Inside the rotating cylinder portion 32a, a vertical transmission shaft having an axial center in the vertical (up and down) direction is rotatably supported around the axial center. The central axis (axle) 5a of the wheel 5 is inserted and supported at the lower end portion of the rotating cylinder portion 32a. In other words, the axle 5a protrudes outward to the left and right from the lower part of the rotating cylinder portion 32a of the wheel drive case 32, and the wheel 5 provided around the axle 5a is disposed on the left and right outer sides of the rotating cylinder portion 32a.

[0107] In addition, inside the upper part of the wheel drive case 32, a transmission mechanism having a bevel gear, an endless belt, or the like that interlocks and links the output shaft of the traveling motor 7 and the upper part of the transmission shaft on the vertical axis of the rotating cylinder part 32a is housed. Further, inside the lower part of the rotating cylinder part 32a, a transmission mechanism having a bevel gear or the like that interlocks and links the lower part of the vertical transmission shaft inside the rotating cylinder part 32a and the axle 5a of the wheel 5 is housed.

[0108] Hereinafter, it is assumed that the traveling frame 30 supports the wheel drive case 32 that supports the axle 5a of the wheel 5, and thus, it may be described that the traveling frame 30 supports the axle 5a.

[0109] With the above configuration, inside the wheel drive case 32, the output of the traveling motor 7 is transmitted to the wheel 5 via a transmission mechanism such as a bevel gear mechanism, and thereby the wheel 5 is driven. That is, the left front wheel 5FL, the right front wheel 5FR, the left rear wheel 5RL, and the right rear wheel 5RR are drive wheels driven by the output of the traveling motor 7 each has individually.

[0110] Hereinafter, it is assumed that the traveling motor 7 of the front wheel unit 4F in each traveling structure 3 may be referred to as the front traveling motor 7F, and the traveling motor 7 of the rear wheel unit 4R may be referred to as the rear traveling motor 7R.

[0111] Also, the traveling motor 7 of the left front wheel unit 4FL in the left traveling structure 3L may be referred to as the left front traveling motor 7FL, and the traveling motor 7 of the left rear wheel unit 4RL may be referred to as the left rear traveling motor 7RL. The traveling motor 7 of the right front wheel unit 4FR in the right traveling structure 3R may be referred to as the right front traveling motor 7FR, and the traveling motor 7 of the right rear wheel unit 4RR may be referred to as the right rear traveling motor 7RR.

[0112] The upper part of the wheel drive case 32 that houses the traveling motor 33 and the like is attached and fixed to the traveling frame 30. On the other hand, with respect to the upper part, the rotating cylinder part 32a is rotatable around the vertical axis.

[0113] The wheel drive case 32 is externally provided with a steering gear mechanism 34 for relatively rotating the rotating cylinder portion 32a with respect to the upper portion of the wheel drive case 32. The steering gear mechanism 34 is provided with an arm, and a steering cylinder 35 is interposed between the arm and the traveling frame 30.

[0114] Referring to FIG. 14 and the like, when the steering cylinder 35 expands and contracts according to a command from the control device 15 or the like, the arm rotates, and thereby the steering gear mechanism 34 operates, and each wheel drive case 32's rotating cylinder portion 32a rotates about its vertical axis while supporting the wheel 5. That is, the wheel 5 is a drive wheel driven by the traveling motor 7 as described above, and is a steering wheel that can rotate relative to the traveling frame 30 in the left-right direction, that is, can change the angle in the left-right direction.

[0115] Each traveling motor 7 is an electric motor, and the traveling motors 7 of the front wheel unit 4F and the rear wheel unit 4R are driven by obtaining electric power from the side battery 37 and / or the center battery 50. Further, an inverter 6 for output control of the traveling motor 7 is provided in the traveling structure 3. As shown in FIG. 14, the inverter 6 is controlled by the control device 15 to control the output rotation speed and output rotation direction of the corresponding traveling motor 7.

[0116] In the block diagram of FIG. 14, only the combination of the traveling motor 7 and the inverter 6 for one wheel unit 4 is shown, but the wheel unit 4 here represents each of the four wheel units 4FL, 4FR, 4RL, and 4RR, and the control device 15 controls the inverter 6 for each individual wheel unit 4 to individually control the rotation speed and rotation direction of each wheel 5.

[0117] The traveling frame 30 of each traveling structure 3 supports the side battery 37, the front inverter 6F for the front traveling motor 7F of the front wheel unit 4F, and the rear inverter 6R for the rear traveling motor 7R of the rear wheel unit 4R.

[0118] As shown in FIG. 1 and the like, the side battery 37 is housed in a side battery case 36 supported by a traveling frame 30 between the front wheels 5F and the rear wheels 5R. By the traveling frame 30, a front inverter 6F for the front traveling motor 7F is supported immediately in front of the side battery case 36, and a rear inverter 6R for the rear traveling motor 7R is supported immediately behind the side battery case 36.

[0119] Hereinafter, the side battery 37 supported by the left traveling frame 30L of the left traveling structure 3L may be referred to as the left side battery 37L, the front inverter 6F supported by the left traveling frame 30L may be referred to as the left front inverter 6FL, and the rear inverter 6R supported by the left traveling frame 30L may be referred to as the left rear inverter 6RL.

[0120] Also, the side battery 37 supported by the right traveling frame 30R of the right traveling structure 3R may be referred to as the right side battery 37R, the front inverter 6F supported by the right traveling frame 30R may be referred to as the right front inverter 6FR, and the rear inverter 6R supported by the right traveling frame 30R may be referred to as the right rear inverter 6RR.

[0121] Also, in each traveling structure 3, the front traveling motor 7F and the front inverter 6F are electrically connected, and the combination of the front traveling motor 7F and the front inverter 6F may be referred to as a front traveling system electric unit E3F (see FIG. 13). On the other hand, the rear traveling motor 7R and the rear inverter 6R are electrically connected, and the combination of the rear traveling motor 7R and the rear inverter 6R may be referred to as a rear traveling system electric unit E3R (see FIG. 13).

[0122] Furthermore, the combination of the left front inverter 6FL and the left front drive motor 7FL in the left traveling structure 3L is referred to as the left front traveling system electric unit E3FL, and the combination of the left rear inverter 6RL and the left rear drive motor 7RL is referred to as the left rear traveling system electric unit E3RL. Similarly, the combination of the right front inverter 6FR and the right front drive motor 7FR in the right traveling structure 3R is referred to as the right front traveling system electric unit E3FR, and the combination of the right rear inverter 6RR and the right rear drive motor 7RR is referred to as the right rear traveling system electric unit E3RR (see Fig. 21).

[0123] Note that, similar to the aforementioned drive motor 7 and inverter 6, only one steering cylinder 35 is shown in the block diagram of Fig. 14. However, this steering cylinder 35 means the one provided in each wheel unit 4. The control device 15 individually controls the steering angle (left and right turning angles) of each wheel 5 by controlling the control valve for the steering cylinder 35 of each wheel unit 4.

[0124] Each steering cylinder 35 may be configured with something other than a hydraulic cylinder, such as an air cylinder or a water pressure cylinder. In addition to such a telescopic actuator, the actuator for steering the wheel 5 may be configured to rotate the rotating cylinder portion 32a by outputting a rotational force, such as an electric motor or a hydraulic motor.

[0125] At the front of each traveling frame 30, a radiator 71, a radiator fan 71a, a pair of electric cooling water pumps 72A and 72B, and a reservoir tank (cooling water storage tank) 73 are provided.

[0126] As shown in Fig. 13, the electric cooling water pump 72A sucks the cooling water from the reservoir tank 73 and supplies it to the front drive motor 7F and the front inverter 6F (front traveling system electric unit E3F) of the front wheel unit 4F to cool them. The electric cooling water pump 72B sucks the cooling water from the reservoir tank 73 and supplies it to the rear drive motor 7R and the rear inverter 6R (rear traveling system electric unit E3R) of the rear wheel unit 4R to cool them.

[0127] Note that, regarding the pair of electric cooling water pumps 72 provided at the front portion of each traveling frame 30 shown in FIG. 1 etc., either one may be used as the electric cooling water pump 72A for the front traveling system electric unit E3F, and either one may be used as the electric cooling water pump 72B for the rear traveling system electric unit E3R.

[0128] The radiator 71 is a cooling device (air cooling device) that cools the cooling water discharged from the electric cooling water pumps 72A and 72B and circulated within the traveling structure 3. The radiator fan 71a is driven by obtaining power from the side battery 37 and / or the center battery 50, and promotes the heat exchange of the cooling water in the radiator 71.

[0129] Note that, as shown in FIG. 2 etc., the front end portion of the traveling frame 30 is inclined rearward from the left and right inner sides to the left and right outer sides in plan view, the radiator 71 is arranged to extend in the vertical direction along the front end portion of the traveling frame 30, and, as shown in FIG. 2 etc., in plan view, it is arranged in an inclined shape parallel to the front end portion of the inclined traveling frame 30. That is, the radiator 71 is arranged in an inclined shape such that the front end is closer to the left and right inner sides and the rear end is closer to the left and right outer sides.

[0130] Thus, nothing is arranged in front of the radiator 71 arranged at the front end portion of the traveling frame 30 (traveling structure 3). For this reason, the front surface of the radiator 71 is not shielded by other members, the radiator 71 can efficiently take in outside air, and the heat exchange efficiency can be made good.

[0131] Also, the radiator 71 is arranged in an inclined shape as described above in plan view so as to face the upper front portion of the grounding (tread) surface of the front wheel 5F above the front of the front wheel 5F. In this way, the radiator 71 is arranged within the limited left and right width of the traveling frame 30 without protruding from the left and right ends (the end on the vehicle body 2 side and the end on the side opposite to the vehicle body 2) of the traveling frame 30 at the front portion of the traveling frame 30.

[0132] Further, as shown in FIGS. 2, 5, 6, etc., the left and right outer end faces of the traveling frame 30 are substantially flush with the left and right outer end faces of the wheels 5 (front wheels 5F and rear wheels 5R) supported by the traveling frame 30. Therefore, the radiator 71 does not protrude beyond the left and right outer ends of the wheels 5.

[0133] Thus, as shown in FIG. 9, in each traveling structure 3, a water-cooled cooling (temperature adjustment) circuit R2 is configured by providing a cooling water passage for circulating cooling water among the radiator 71, electric cooling water pumps 72A and 72B, the front traveling system electric unit E3F, the rear traveling system electric unit E3R, and the like.

[0134] That is, the water-cooled cooling (temperature adjustment) circuit R2 includes, as a parallel circuit, a cooling water supply circuit for the front traveling system electric unit E3F (such as the front traveling motor 7F) and a cooling water supply circuit for the rear traveling system electric unit E3R (such as the rear traveling motor 7R). Since a pair of electric cooling water pumps 72 are provided as pumps for individually discharging cooling water into these parallel cooling water supply circuits, cooling water can be efficiently supplied to each cooling target device (that is, each of the front traveling system electric unit E3F (such as the front traveling motor 7F) and the rear traveling system electric unit E3R (such as the rear traveling motor 7R)), and the flow of each cooling water can be individually controlled.

[0135] Note that the water-cooled cooling (temperature adjustment) circuit R2 provided in the left traveling structure 3L may be referred to as the left water-cooled cooling (temperature adjustment) circuit R2L, and the water-cooled cooling (temperature adjustment) circuit R2 provided in the right traveling structure 3R may be referred to as the right water-cooled cooling (temperature adjustment) circuit R2R.

[0136] Next, a first embodiment regarding the air-cooling system in the work vehicle 1 will be described with reference to FIGS. 1 to 11, etc. As described above, the work vehicle 1 is provided with an air-conditioning unit 51 at the front part of the vehicle body 2.

[0137] The air conditioner unit 51 has a compressor, a heat exchanger, a discharge port, an air intake port 51a, etc. The air compressed by the compressor is cooled by the heat exchanger, and the air is discharged from the discharge port as cooling air, and the air after cooling each equipment to be cooled is collected at the air intake port 51a.

[0138] The work vehicle 1 includes, as equipment to be cooled by the cooling air discharged from the air conditioner unit 51 as an air-cooled cooling device, a center battery 50 provided on the vehicle body 2, side batteries 37 provided on the left and right traveling structures 3, and the like.

[0139] That is, the cooling air from the air conditioner unit 51 provided on the vehicle body 2 is distributed and supplied to the equipment to be cooled arranged at three positions of the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R.

[0140] The duct structure in the air-cooling system according to the first embodiment shown in FIGS. 1 to 11 and the like constitutes a cooling air circulation circuit for supplying and collecting the cooling air from such an air conditioner unit 51 to each equipment to be cooled.

[0141] First, in the present embodiment, the center battery case 24 for housing the center battery 50 has a cooling air inlet 24a at the lower part of the front end and a cooling air outlet 24b at the upper part of the front end as shown in FIG. 10. A discharge manifold 41a is provided between the discharge port provided at the rear part of the air conditioner unit 51 and the cooling air inlet 24a at the front end of the center battery case 24.

[0142] The center battery case 24 has a horizontally plate-shaped partition plate 24e extending in the front-rear direction inside. The space below the partition plate 24e is used as a cooling air passage 24c for applying air as cooling air to the center battery 50 as the equipment to be cooled and allowing it to pass through. The space above the partition plate 24e is used as an exhaust air passage 24d for sending the air after cooling the center battery 50 to the cooling air outlet 24b.

[0143] The partition plate 24e is arranged at a position higher than approximately half of the height of the center battery case 24 in the vertical direction, and the vertical width of the cooling air passage 24c is larger than the vertical width of the exhaust air passage 24d. That is, within the center battery case 24, a relatively large volume of space for applying cooling air to the center battery 50 can be ensured.

[0144] Also, the partition plate 24e insulates between the exhaust air passage 24d and the cooling passage 24c. Specifically, the partition plate 24e is formed of a heat-insulating material or provided with a heat-insulating material, so that the temperature of the warmed air passing through the exhaust air passage 24d is not transmitted to the cooling air passage 24c.

[0145] Within the center battery case 24, a partition plate 24f extending in the vertical direction is connected to the rear end of the partition plate 24e, and the partition plates 24e and 24f are arranged in an inverted L shape when viewed from the left side. The space behind the partition plate 24f is defined as a communication passage 24g. In this way, the rear part of the cooling air passage 24c and the rear part of the exhaust air passage 24d communicate with each other via the vertical communication passage 24g.

[0146] The cooling air adjusted in temperature by the air conditioner unit 51 and discharged from the discharge manifold 41a is introduced into the center battery case 24 through the cooling air inlet 24a at the front end of the center battery case 24 without passing through a duct. The cooling air introduced from the cooling air inlet 24a flows backward in the cooling air passage 24c and is applied to the center battery 50 on the way to cool the center battery 50.

[0147] In the cooling air passage 24c, after cooling the center battery 50, the cooling air is conversely warmed by the center battery 50 and becomes hotter than when it was introduced from the cooling air inlet 24a into the cooling air passage 24c. The thus heated cooling air moves upward in the communication passage 24g and flows into the exhaust air passage 24d above the cooling air passage 24c.

[0148] Furthermore, the cooling air after cooling the center battery 50 flows forward within the exhaust passage 24d and is discharged forward of the center battery case 24 from the cooling air outlet 24b at the front end of the center battery case 24.

[0149] As shown in FIG. 3, FIG. 10, etc., an air conditioner case 40 for housing the air conditioner unit 51 is provided immediately in front of the center battery case 24, and the air intake port 51a of the air conditioner unit 51 is open toward the space in the air conditioner chamber 40a within the air conditioner case 40.

[0150] The cooling air discharged from the cooling air outlet 24b to the outside of the center battery case 24 is sucked into (returned to) the air conditioner unit 51 through the space in the air conditioner chamber 40a and the air intake port 51a.

[0151] Note that an intake manifold (refer to the intake manifold 51b in FIG. 19) communicating with the air intake port 51a may be provided in the air conditioner unit 51, and a duct from the cooling air outlet 24b to the intake manifold may be provided.

[0152] Also, within the center battery case 24, a fan 45 is disposed at a location where the rear end of the cooling air passage 24c and the lower portion of the communication passage 24g communicate below the vertical partition plate 24f.

[0153] The fan 45 is configured to suck air within the front cooling air passage 24c and discharge it to the rear communication passage 24g.

[0154] That is, the fan 45 sucks the air that has flowed into the cooling air passage 24c from the cooling air inlet 24a at the rear end of the cooling air passage 24c and guides it to the communication passage 24g, thereby causing a rearward cooling air flow within the cooling air passage 24c.

[0155] Also, the fan 45 causes an upward air flow within the communication passage 24g and a forward air flow within the exhaust passage 24d by exhausting air rearward.

[0156] In this way, the fan 45 smooths the flow of the cooling air from the cooling air inlet 24a to the cooling air outlet 24b within the center battery case 24.

[0157] Next, a configuration for cooling air circulation between the air conditioner unit 51 and the side battery cases 36L and 36R of the left and right traveling structures 3L and 3R will be described.

[0158] The work vehicle 1 includes a vehicle body 2, a cooling device provided on the vehicle body 2, at least one device to be cooled by the cooling air discharged from the cooling device, and a plurality of ducts for circulating the cooling air between the cooling device and the device to be cooled. The vehicle body 2 has a first end portion and a second end portion facing each other in a first direction, and an intermediate portion between the first end portion and the second end portion in the first direction. The air conditioner unit 51 is provided at the first end portion of the vehicle body 2. Among the plurality of ducts, the duct extending from the air conditioner unit 51 to the device to be cooled has a first extension portion extending in the first direction in the range from the first end portion to the intermediate portion, and a second extension portion extending in a direction different from the first direction at the intermediate portion.

[0159] In the present embodiment, the cooling device is the air conditioner unit 51 which is an air temperature adjustment device (air conditioner), but any device that discharges cooling air for cooling the device to be cooled may be used, such as a fan. Also, a heat pump type device using engine heat or the like may be used.

[0160] Further, as the device to be cooled, in the present embodiment, it is the battery (the center battery 50 provided in the vehicle body 2 and the side batteries 37 provided in each traveling structure 3), but any device that can be cooled by the cooling air may be used, and hydraulic devices such as hydraulic pumps or electrical devices such as electric motors may also be used as the device to be cooled.

[0161] Moreover, a structure in which at least one device to be cooled is cooled by a plurality of ducts may be used. In the present embodiment, for example, the forward duct 42 and the return duct 43 described later, which are used to cool the side battery 37 provided in one of the left and right traveling structures 3, correspond to the plurality of ducts. Also, the pair of left and right forward ducts 42L and 42R described later, which are used to cool the left and right side batteries 37L and 37R, also correspond to the plurality of ducts.

[0162] The vehicle body 2 has a first end portion and a second end portion that face each other in a first direction, and an intermediate portion that is between the first end portion and the second end portion in the first direction. The cooling device is provided at the first end portion of the vehicle body 2. In the present embodiment, the first direction is the front-rear direction, the first end portion is the front end portion, and the second end portion is the rear end portion. However, the present invention is not limited to this. The first end portion may be the rear end portion and the second end portion may be the front end portion, or the first direction may be, for example, the left-right direction, and the first end portion and the second end portion may be the left end portion and the right end portion. Furthermore, the first direction may be an oblique direction.

[0163] Among the plurality of ducts described above, the duct that extends from the cooling device (air conditioner unit 51) to the device to be cooled has a first extension portion that extends in the first direction in the range from the first end portion to the intermediate portion, and has a second extension portion that extends in a direction different from the first direction at the intermediate portion of the vehicle body 2.

[0164] In the second extension portion (the extension portion 42b described later in the present embodiment) that extends in a direction different from the first direction In the present embodiment, the intermediate portion of a certain vehicle body 2 is set as a position corresponding to the side battery case 36 disposed at a substantially middle position in the front-rear direction of the traveling structure 3 in the front-rear direction. However, the present invention is not limited to this. For example, when the side battery case 36 is disposed at a position closer to the rear end portion of the traveling structure 3, the intermediate portion of the vehicle body 2 where the second extension portion is provided may be defined as a position closer to the rear end of the vehicle body 2. Alternatively, even if the side battery case 36 remains disposed at a substantially middle position in the front-rear direction of the traveling structure 3, the intermediate portion of the vehicle body 2 where the second extension portion is provided may be set as a position closer to the rear end of the vehicle body 2, which is behind the side battery case 36.

[0165] Also, in the present embodiment, the direction in which the second extension portion extends in a direction different from the first direction is defined as the left - right direction. However, this portion is not limited to extending in such a direction and may extend in the up - down direction. Also, if the first direction is a direction other than the front - rear direction, it is conceivable to define that direction as the front - rear direction.

[0166] Hereinafter, with respect to the structure of an air - cooling system in which the equipment to be cooled by the cooling air discharged from the air - conditioner unit 51 as a cooling device is the center battery 50 provided in the vehicle body 2 and the side batteries 37 provided in the left and right traveling structures 3L and 3R, while explaining the air - cooling system according to the first embodiment shown in FIGS. 1 to 11 and the like, the structures common to the second embodiment in FIGS. 15 to 18 and the third embodiment in FIGS. 19 to 20 will also be described.

[0167] First, the cooling - air circulation structure between the air - conditioner unit 51 and the side battery 37 will be described. As shown in FIG. 10 and the like, as a discharge port of the cooling air from the air - conditioner unit 51 to the side - battery case 36, a discharge manifold 41b that protrudes above the vehicle body 2 (the vehicle - body center frame 21) is provided above the air - conditioner unit 51.

[0168] In order to supply the cooling air discharged from the air - conditioner unit 51 to the side battery 37, an upstream duct 42 extends from the air - conditioner unit 51 to the side battery 37. That is, the upstream duct 42 corresponds to the duct that extends from the cooling device (air - conditioner unit 51) to the equipment to be cooled (side battery 37) among the plurality of ducts that allow the cooling air to flow between the cooling device (air - conditioner unit 51) and the equipment to be cooled (side battery 37).

[0169] Incidentally, the forward duct 42 is specifically extended from the discharge manifold 41b disposed at the front end of the vehicle body 2 to the cooling air inlet 36a (see FIG. 11) of the side battery case 36 which is a housing for accommodating the side battery 37. In the range from the front end of the vehicle body 2 (an example of the first end) to the middle part in the front-rear direction, it is piped so as to pass through the upper part of the vehicle body 2 (the upper part of the vehicle body side frame 22).

[0170] On the upper part of the vehicle body side frame 22 (the upper part of the vehicle body 2), the forward duct 42 has a first extension part 42a extending in the front-rear direction (an example of the first direction) along the vehicle body side frame 22 to the middle part in the front-rear direction of the vehicle body 2. Further, the forward duct 42 bends at the middle part in the front-rear direction of the vehicle body 2 on the vehicle body side frame 22 and extends outward to the left and right toward the traveling structure 3 outside the vehicle body 2 in the left-right direction. That is, the forward duct 42 has an extension part (second extension part) 42b extending in the left-right direction different from the front-rear direction with the bent part as the rear end of the extension part 42a.

[0171] The configuration of the forward duct 42 described above is the same in the second embodiment shown in FIGS. 15 to 18 and also in the third embodiment shown in FIGS. 19 and 20.

[0172] On the other hand, a return duct 43 is extended from the side battery 37 in order to return the cooling air after cooling the side battery 37 to the air conditioner unit 51. Specifically, the return duct 4 3 is extended from the cooling air outlet 36b (see FIG. 11) of the side battery case 36 which is a housing for accommodating the side battery 37.

[0173] In the present embodiment (the first embodiment) and the third embodiment shown in FIGS. 19 and 20, the return duct 43 extends to the vicinity of the air inlet 51a of the air conditioner unit 51, and has a structure that returns the cooling air after cooling the side battery 37 in the traveling structure 3 to the air conditioner unit 51 in the vehicle body 2. That is, in the present embodiment, the return duct 43 corresponds to a duct that extends from the cooling device (air conditioner unit 51) to the device to be cooled (side battery 37) among a plurality of ducts through which the cooling air circulates between the cooling device (air conditioner unit 51) and the device to be cooled (side battery 37).

[0174] Therefore, in the present embodiment (the first embodiment) and the third embodiment, the return duct 43 first has an extension portion 43b that extends in the left-right direction (different from the front-rear direction (the first direction)) from the side battery case 36 provided in the traveling structure 3 toward the vehicle body 2 on the left and right inner sides thereof. This extension portion 43b is arranged in parallel with the extension portion (the second extension portion) 42b of the forward duct 42 that also extends in the left-right direction.

[0175] Furthermore, in the present embodiment (the first embodiment) and the third embodiment, the return duct 43 passes through the upper part of the vehicle body 2 (the upper part of the vehicle body center frame 21), connects its outlet end to the upper end of the air conditioner case 40, and returns the cooled air from the outlet end to the air inlet 51a through the air conditioner chamber 40a in the air conditioner case 40. In the upper part of the vehicle body 2, the return duct 43 has an extension portion (the first extension portion) 43a that extends in the front-rear direction in the range from the front end portion (the first end portion) of the vehicle body 2 to the midpoint in the front-rear direction, and this extension portion 43a and the extension portion (the first extension portion) 42a of the forward duct 42 are arranged in parallel.

[0176] Note that in the second embodiment described later shown in FIGS. 15 and 16, etc., the return duct 43 does not extend to the air conditioner unit 51, but is connected to the center battery case 24, and the air after cooling the side battery 37 is merged with the air after cooling the center battery 50 and then returned to the air inlet 51a of the air conditioner unit 51.

[0177] That is, in the second embodiment, since the return duct 43 is connected to the center battery case 24 supported by the vehicle body 2, although it has a lateral extension 43b, it does not have a longitudinal extension (first extension) 43a that is disposed above the vehicle body 2.

[0178] On the other hand, in the second embodiment, the supply duct 42 extends from the discharge manifold 41b to the cooling air inlet 36a of the side battery case 36 in the same manner as in the first embodiment, has a longitudinal extension 42a above the vehicle body 2, and has a lateral extension 42b from the vehicle body 2 to the traveling structure 3, without any change in this regard.

[0179] That is, as a structure common to the first and second embodiments, at least the supply duct 42 among the supply duct 42 and the return duct 43 has a longitudinal extension (first extension) 42a extending in the longitudinal direction (first direction) as described above, and further has a lateral extension 42b extending in a lateral direction different from the longitudinal direction at a midpoint in the longitudinal direction of the vehicle body 2. The return duct 43 has at least a lateral extension 43b extending in a lateral direction different from the longitudinal direction in which the extension 42a of the supply duct 42 extends, and the extension 43b is arranged in parallel with the lateral extension (second extension) 42b of the supply duct 42 extending in the lateral direction.

[0180] Here, the side battery case 36 will be described. As shown in FIG. 11, in the side battery case 36 of each traveling structure 3, a cooling air inlet 36a is provided at the lower part of the front end face 36f, and a cooling air outlet 36b is provided at the upper part of the rear end face 36r. In addition, in FIG. 11, "36s" indicates the left and right outer surfaces between the front end face 36f and the rear end face 36r of the side battery case 36.

[0181] The cooling air inlet 36a connected to the forward duct 42 is provided at the lower part of the side battery case 36, and the cooling air outlet 36b connected to the return duct 43 is provided at the upper part of the side battery case 36. This is to ensure that the warmed air after cooling the side battery 37 inside the side battery case 36 does not warm the cooling air before cooling, and to enable the efficient discharge of the cooled air from the side battery case 36.

[0182] Furthermore, one of the cooling air inlet 36a and the cooling air outlet 36b is arranged closer to the left and right inner sides, and the other is arranged closer to the left and right outer sides, so that the flow of the cooling air forms a diagonal line in the left and right directions in a plan view from the front-end cooling air inlet 36a to the rear-end cooling air outlet 36b inside the side battery case 36, maximizing the cooling effect of the side battery 37.

[0183] Note that the layout of the cooling air inlet 36a connected to the forward duct 42 and the cooling air outlet 36b connected to the return duct 43 in the side battery case 36 is not limited to the layout shown in FIG. 11. For example, at least one of the cooling air inlet 36a and the cooling air outlet 36b may be provided on the left and right outer surfaces 36s or the opposite left and right inner surfaces.

[0184] In this embodiment, considering the routing of the ducts and the like, the cooling air inlet 36a and the forward duct 42 connected thereto are arranged closer to the left and right inner sides, and the cooling air outlet 36b and the return duct 43 connected thereto are arranged closer to the left and right outer sides. The side battery case 36 in FIG. 11 has the cooling air inlet 36a arranged on the right side and the cooling air outlet 36b arranged on the left side, so it is the left side battery case 36L.

[0185] Note that, as shown in FIG. 2 and the like, the front inverter 6F is provided along the front end face 36f of the side battery case 36 on the left and right outer sides of the forward duct 42 connected to the cooling air inlet 36a of the side battery case 36, and the rear inverter 6R is provided along the rear end face 36r of the side battery case 36 on the left and right inner sides of the return duct 43 connected to the cooling air outlet 36b of the side battery case 36.

[0186] Note that the side battery 37, which is the equipment to be cooled, includes a left side battery 37L, which is a left equipment to be cooled arranged on the left traveling structure 3L, and a right side battery 37R, which is a right equipment to be cooled arranged on the right traveling structure 3R.

[0187] Correspondingly, as a structure common to the first to third embodiments, a plurality of ducts for circulating cooling air between the air conditioner unit 51 (cooling device) and the left and right side batteries 37L, 37R (equipment to be cooled) include a left forward duct 42L extending to the left side battery 37L and a right forward duct 42R extending to the right side battery 37R for supplying the cooling air discharged from the air conditioner unit 51 to the left and right side batteries 37L, 37R, and a left return duct 43L extending from the left side battery 37L and a right return duct 43R extending from the right side battery 37R for returning the cooling air after cooling the left and right side batteries 37L, 37R to the air conditioner unit 51.

[0188] Among these forward ducts 42L, 42R and return ducts 43L, 43R, at least the left forward duct 42L and the right forward duct 42R extend from the air conditioner unit 51 to the left side battery 37L and the right side battery 37R respectively, and are ducts having an extension part (first extension part) 42a extending in the front-rear direction (first direction) in the range from the front end part (first end part) to the front-rear middle part (middle part). Further, an extension part (second extension part) 42b extending in the left-right direction different from the front-rear direction (first direction) of the left forward duct 42L and the front... The extension part (second extension part) 42b extending in the left - right direction different from the rear direction (first direction) extends in directions opposite to each other with respect to the vehicle body 2.

[0189] The left return duct 43L and the right return duct 43R each have an extension part 43b extending in the left - right direction different from the front - rear direction (first direction), and the extension part 43b of the left return duct 43L extending in the left - right direction different from the front - rear direction (first direction) and the extension part 43b of the right return duct 43R extending in the left - right direction different from the front - rear direction (first direction) extend in directions opposite to each other with respect to the vehicle body 2.

[0190] Hereinafter, the specific piping routes of the forward duct 42 and the return duct 43 in the first embodiment shown in FIGS. 1 to 10 etc., and the layout of a plurality of ducts including the left and right forward ducts 42L, 42R and the left and right return ducts 43L, 43R will be described in detail.

[0191] The forward duct 42 is piped so as to pass through the upper part of the vehicle body 2 (the upper part of the vehicle - body side frame 22) from the discharge manifold 41b to the cooling air inlet 36a of the side battery case 36 of each traveling structure 3.

[0192] That is, the left forward duct 42L is piped so as to pass through the upper left part of the vehicle body 2 (the upper part of the left vehicle - body side frame 22L) from the left part of the discharge manifold 41b to the cooling air inlet 36a of the left side battery case 36L of the left traveling structure 3L. On the other hand, the right forward duct 42R is piped so as to pass through the upper right part of the vehicle body 2 (the upper part of the right vehicle - body side frame 22R) from the right part of the discharge manifold 41b to the cooling air inlet 36a of the right side battery case 36R of the right traveling structure 3R.

[0193] Also, the return duct 43 is piped so as to pass through the upper part of the vehicle body 2 (the upper part of the vehicle - body center frame 21) from the cooling air outlet 36b of the side battery case 36 of each traveling structure 3 to the upper end of the air - conditioner case 40.

[0194] That is, the left return duct 43L is piped so as to pass through the upper left part of the vehicle body 2 (the upper left part of the vehicle body center frame 21) from the cooling air outlet 36b of the left side battery case 36L of the left traveling structure 3L to the left part of the upper end of the air conditioner case 40. On the other hand, the right return duct 43R is piped so as to pass through the upper right part of the vehicle body 2 (the upper right part of the vehicle body center frame 21) from the cooling air outlet 36b of the right side battery case 36R of the right traveling structure 3R to the right part of the upper end of the air conditioner case 40.

[0195] As can be seen in the plan view of FIG. 9 and the like, 42L, 42R, 43L, and 43R have extending portions 42a and 43a that extend linearly in the front-rear direction.

[0196] These extending portions 42a and 43a are piped in parallel with each other in the front-rear direction within the range from the front part of the vehicle body 2 to the position that becomes the midpoint in the front-rear direction (in the front-rear direction, the position corresponding to the side battery case 36 (more precisely, the front end of the side battery case 36) in the left and right traveling structures 3) at the upper part of the vehicle body 2.

[0197] Regarding the arrangement in the left-right direction of the extending portions 42a and 43a of the ducts 42L, 42R, 43L, and 43R, the extending portion 43a of the left return duct 43L and the extending portion 43a of the right return duct 43R are juxtaposed in parallel left and right at the upper part of the vehicle body center frame 21. On the left side of the extending portion 43a of the left return duct 43L, the extending portion 42a of the left forward duct 42L is arranged on the left vehicle body side frame 22L, and on the right side of the extending portion 43a of the right return duct 43R, the extending portion 42a of the right forward duct 42R is arranged on the right vehicle body side frame 22R.

[0198] The left forward duct 42L extends obliquely upward from the front end connected to the discharge manifold 41b arranged on the vehicle body center frame 21, bends rearward above the left vehicle body side frame 22L, and from there, extends the extending portion 42a in the front-rear direction above the left vehicle body side frame 22L.

[0199] Furthermore, the left return duct 42L is disposed on the left body side frame 22L at a position slightly forward in the front-rear direction from the front end of the left side battery case 36L of the left traveling structure 3L. It bends substantially at a right angle in plan view from the front-rear extending portion 42a and extends the left-right extending portion 42b to the left, crosses over to the left traveling frame 30L, bends at a position directly in front of the left side battery case 36L and extends downward, and is connected to the cooling air inlet 36a at the front end of the left side battery case 36L.

[0200] The right return duct 42R extends from the front end connected to the discharge manifold 41b disposed on the vehicle body center frame 21 diagonally upward to the right, bends rearward above the right body side frame 22R, and from there, extends the front-rear extending portion 42a above the right body side frame 22R.

[0201] Furthermore, the right return duct 42R is disposed on the right body side frame 22R at a position slightly forward in the front-rear direction from the front end of the right side battery case 36R of the right traveling structure 3R. It bends substantially at a right angle in plan view from the front-rear extending portion 42a and extends the left-right extending portion 42b to the right, crosses over to the right traveling frame 30R, bends at a position directly in front of the right side battery case 36R and extends downward, and is connected to the cooling air inlet 36a at the front end of the right side battery case 36R.

[0202] The left return duct 43L is disposed on the vehicle body center frame 21 at a position slightly rearward in the front-rear direction from the front end of the left side battery case 36L of the left traveling structure 3L. It bends substantially at a right angle in plan view from the front-rear extending portion 43a and extends the left-right extending portion 43b to the left, crosses over the left body side frame 22L and reaches the left traveling frame 30L, further bends, extends rearward above the left side battery case 36L, bends again at the rear of the left side battery case 36L and extends downward, and is connected to the cooling air outlet 36b at the rear end of the left side battery case 36L.

[0203] The right return duct 43R is disposed on the vehicle body center frame 21 at a position slightly rearward of the front end of the right side battery case 36R of the right traveling structure 3R in the front-rear direction. It bends substantially at a right angle in plan view from the front-rear extending portion 43a and extends leftward as a left-right extending portion 43b, crosses over the right vehicle side frame 22R to the right traveling frame 30R, further bends, extends rearward above the right side battery case 36R, bends again at the rear of the right side battery case 36R and extends downward, and is connected to the cooling air outlet 36b at the rear end of the right side battery case 36R.

[0204] Now, the work vehicle 1 shown in FIGS. 1 to 10 etc. has a structure capable of changing the "vehicle shape", and is provided with a duct that can expand and contract in response to such a "change in vehicle shape".

[0205] The ducts 42 and 43 as the above-described cooling air passages are such expandable and contractible ducts. Note that other expandable and contractible ducts are also conceivable. For example, when the work vehicle 1 is equipped with an engine as a prime mover, the intake pipe or exhaust pipe of the engine etc. may be such an expandable and contractible duct. Also, what is circulated through the duct may be a cooling medium, and in addition to the air as the cooling air as described above, a refrigerant gas etc. is also conceivable.

[0206] Here, the "change in vehicle shape" is considered to be the relative movement of the "first part and the second part that are linked to be relatively movable to each other" provided in the work vehicle 1, but it is not limited to such a form. For example, any part of the work vehicle (for example, a cover covering the frame etc.) is made of a material having plasticity, stretchability or elasticity etc., and the part itself deforms due to its physical properties, or any part of the work vehicle (for example, a roof member covering the boarding seat when the work vehicle is provided with a boarding seat etc.) is detachable, and changing the vehicle shape based on the attachment and detachment of the part etc. may also fall under the "change in vehicle shape".

[0207] ​Also, the "first part and the second part that are linked so as to be relatively movable with respect to each other" in the above-described structure corresponds to the center battery case (front main body case) 24 and the vehicle body frame structure 20 (such as the vehicle body center frame 21) that are linked so as to be relatively movable in the front-rear direction with respect to each other, the vehicle body center frame 21 and the vehicle body side frame 22 (left vehicle body side frame 22L, right vehicle body side frame 22R) that are linked so as to be relatively movable in the left-right direction with respect to each other, and the vehicle body 2 (vehicle body side frame 22) and the traveling structure 3 (traveling frame 30) that are linked so as to be relatively movable in the up-down direction with respect to each other.

[0208] However, the "first part and the second part that are linked so as to be relatively movable with respect to each other" are not limited to the above. For example, when a working device such as a rotary tiller is connected to the vehicle body 2 via a three-point link type connecting device 60, the vehicle body 2 and the working device relatively move in the up-down direction by the expansion and contraction movement of the lift cylinder 61 provided in the connecting device 60, and such a vehicle body 2 and the working device may also correspond to the "first part" and the "second part". Also, the shape of the working vehicle 1 changes depending on whether the connecting device 60 and the working device are mounted or not. Thus, the "first part" and the "second part" may be any part in the working vehicle 1 as long as they are parts that are linked so as to be relatively movable with respect to each other.

[0209] Also, when the "change in the vehicle shape" is the "relative movement of the first part and the second part that are linked so as to be relatively movable with respect to each other", the "duct that can expand and contract in response to the change in the vehicle shape" is considered to be a "duct that extends across the first part and the second part that are linked so as to be relatively movable with respect to each other and has an expansion and contraction part that can expand and contract in response to the relative movement of the first part and the second part".

[0210] Also, it is conceivable to provide the above-described expansion and contraction part in the part of the duct that is disposed between the first part and the second part of the vehicle body 2, with one of the aforementioned "first part and the second part that are linked so as to be relatively movable with respect to each other" being the first part of the vehicle body 2 and the other being the second part of the vehicle body 2. Alternatively, it is conceivable that one of the first part and the second part is the vehicle body 2 and the other is the traveling structure 3.

[0211] As the "portion disposed between the first portion and the second portion of the vehicle body 2", in the above-described structure, it may be, but is not limited to, a portion disposed between the discharge manifold 41b (which can move integrally with the center battery case 24) and the air conditioner case 40 of the vehicle body 2 and the vehicle body frame structure 20 (such as the vehicle body center frame 21), or a portion disposed between the vehicle body center frame 21 and the vehicle body side frames 22 (left vehicle body side frame 22L and right vehicle body side frame 22R). For example, the vehicle body center frame 21 may be divided into a front portion and a rear portion, these front and rear portions may be linked to be relatively movable in the front-rear direction, and a telescopic portion may be provided in the corresponding portion of a duct extending across the front and rear portions.

[0212] Further, the duct may have at least one telescopic portion in a portion disposed between the first portion and the second portion of the vehicle body 2, or in a portion disposed between the vehicle body 2 and the traveling structure 3, and a plurality of telescopic portions may be provided in the portion. Also, such telescopic portions are not limited to a plurality of them provided in series in the portion. For example, the duct may be in a U-turn shape, and there may be a plurality of portions disposed between the first portion and the second portion of the vehicle body 2, or a plurality of portions interposed between the vehicle body 2 and the traveling structure 3. In such a case, telescopic portions may be provided in each of the plurality of portions. Each of them may be provided with a telescopic portion.

[0213] The above-described forward duct 42 and return duct 43, and the return duct 44 in the third embodiment described later correspond to the ducts having the telescopic portions described above. Hereinafter, the structure of the telescopic portions of each duct will be described in detail.

[0214] As shown in FIG. 2 and the like, the front end portions of the ducts 42 and 43 piped extend forward from the front end of the upper portion of the vehicle body frame structure 20, bend from the extending portions 42a and 43a and extend downward, and are connected to the discharge manifold 41b and the air conditioner case 40 (or intake manifold) provided in the air conditioner unit 51.

[0215] The air conditioner case 40 is continuously provided with the center battery case 24, and the discharge manifold 41b is connected to the air conditioner case 40. When the center battery case 24 moves in the front-rear direction with respect to the vehicle body frame structure 20, the air conditioner case 40 and the discharge manifold 41b also move integrally with the center battery case 24.

[0216] The ducts 42 and 43 each have telescopic portions 42c and 43c that can expand and contract in the front-rear direction in the front-rear extending portions 42a and 43a. As shown in FIG. 8, due to the operation of the battery movement actuator 81 or the like, when the air conditioner case 40 that houses the air conditioner unit 51 and the discharge manifold 41b move in the front-rear direction relative to the vehicle body frame structure 20 together with the center battery case 24, the telescopic portions 42c and 43c expand and contract in response to the movement.

[0217] That is, the ducts 42 and 43 extend across the discharge manifold 41b and the air conditioner case 40 (the first part), which are linked to be relatively movable in the front-rear direction with respect to each other, and the vehicle body frame structure 20 (the second part), and are ducts having telescopic portions 42c and 43c that can expand and contract in response to the relative movement in the front-rear direction. That is, the supply duct 42 has a telescopic portion 42c that can expand and contract in the front-rear direction in the front-rear direction portion disposed between the discharge manifold 41b (the first part of the vehicle body 2) and the vehicle body frame structure 20 (the second part of the vehicle body), and the return duct 43 has a telescopic portion 43c that can expand and contract in the front-rear direction in the front-rear direction portion disposed between the air conditioner case 40 (the first part of the vehicle body 2) and the vehicle body frame structure 20 (the second part of the vehicle body 2).

[0218] The forward duct 42 has a front end connected to the discharge manifold 41b, which is located in front of the front-to-rear extending portion 42a, extending upward and outward to the left and right, and spanning from the vehicle body center frame 21 to the vehicle body side frame 22. Note that the discharge manifold 41b is a part that can move relative to the vehicle body side frame 22 integrally with the vehicle body center frame 21 as long as it does not move relative to the vehicle body frame structure 20 together with the center battery case 24. The front end of the forward duct 42 spanning across the discharge manifold 41b and the vehicle body side frame 22 will span across the vehicle body center frame 21 and the vehicle body side frame 22.

[0219] On the other hand, the return duct 43 has an extending portion 43b that bends at the rear end of the front-to-rear extending portion 43a and extends in the left-right direction, spanning from the vehicle body center frame 21 to the vehicle body side frame 22.

[0220] In this way, the ducts 42 and 43 have telescopic portions 42d and 43d that are stretchable in the left-right direction at the portions that extend in the left-right direction and span from the vehicle body center frame 21 to the vehicle body side frame 22. As can be seen in FIG. 9, when the vehicle body side frame 22 moves relative to the vehicle body center frame 21 in the left-right direction due to the operation of the width change cylinder 8 or the like, the telescopic portions 42d and 43d expand and contract accordingly.

[0221] That is, the ducts 42 and 43 extend across the vehicle body center frame 21 (the first part) and the vehicle body side frame 22 (the second part) that are linked to be relatively movable in the left-right direction with respect to each other, and have telescopic portions 42d and 43d that are stretchable in response to the relative movement in the left-right direction at the left-right direction portion disposed between the vehicle body center frame 21 (the first part of the vehicle body 2) and the vehicle body side frame 22 (the second part of the vehicle body 2).

[0222] The ducts 42 and 43 extend further outward to the left and right from the telescopic portions 42d and 43d on the side frame 22 of the vehicle body, and are bridged to the traveling structures 3 on the left and right outer sides of the vehicle body 2 and connected to the side battery case 36. After being bridged over the upper part of the traveling frame 30, the ducts 42 and 43 are bent and have telescopic portions 42e and 43e that can expand and contract in the vertical direction in the portions extending downward to the cooling air inlet 36a and the cooling air outlet 36b. As can be seen in FIG. 8, when the vehicle body 2 moves vertically relative to the traveling structure 3 due to the operation of the vehicle body lifting cylinder 9 or the like, the telescopic portions 42e and 43e expand and contract accordingly.

[0223] That is, the ducts 42 and 43 extend across the vehicle body 2 (the first part) and the traveling structures 3 (the second part) arranged on the left and right sides of the vehicle body 2, which are linked to be relatively movable in the vertical direction with respect to each other. The ducts have telescopic portions 42e and 43e that can expand and contract in response to the relative movement in the vertical direction in the vertical portions arranged between the vehicle body 2 and the traveling structure 3.

[0224] In addition, the work vehicle 1 includes a traveling structure 3 provided on the side of the vehicle body 2. The vehicle body 2 is relatively movable with respect to the traveling structure 3. The ducts 42 and 43 are provided with a plurality of telescopic portions in the portions arranged between the first part and the second part of the vehicle body 2 and in the portions arranged between the vehicle body 2 and the traveling structure 3.

[0225] That is, the forward duct 42 is a duct provided with a plurality of telescopic portions 42c and 42e in the portion arranged between the discharge manifold 41b (the first part) of the vehicle body 2 and the vehicle body frame structure 20 (the second part) and in the portion arranged between the vehicle body 2 and the traveling structure 3. Also, it is a duct provided with a plurality of telescopic portions 42d and 42e in the portion arranged between the vehicle body center frame 21 (the first part) and the vehicle body side frame 22 (the second part) and in the portion arranged between the vehicle body 2 and the traveling structure 3.

[0226] Further, the return duct 43 is a duct provided with a plurality of expansion joints 43c, 43e, with the expansion joint 43c provided in the front-rear direction portion disposed between the air conditioner case 40 (first part) of the vehicle body 2 and the vehicle body frame structure 20 (second part), and the expansion joints 43d, 43e provided in the portion disposed between the vehicle body 2 and the traveling structure 3. Also, the return duct 43 is a duct provided with a plurality of expansion joints 43d, 43e in the portion disposed between the vehicle body center frame 21 (first part) and the vehicle body side frame 22 (second part), and the portion disposed between the vehicle body 2 and the traveling structure 3.

[0227] As described above, the ducts 42, 43 may have a plurality of expansion joints in the portion disposed between the first part and the second part of the vehicle body 2, or may have a plurality of such portions, each having an expansion joint. The same applies to the portion disposed between the vehicle body 2 and the traveling structure 3.

[0228] Also, when the work vehicle 1 includes a cooling device provided in the first part or the second part, and a device to be cooled provided in the traveling structure 3 and cooled by a cooling medium supplied from the cooling device, the duct provided with a plurality of expansion joints in the portion disposed between the first part and the second part of the vehicle body 2 and the portion disposed between the vehicle body 2 and the traveling structure 3 may extend between the cooling device and the device to be cooled as a passage for the cooling medium.

[0229] In this embodiment, the ducts 42, 43 having a plurality of expansion joints as described above extend between the air conditioner unit 51 provided in the air conditioner case 40 corresponding to the first part or the second part of the vehicle body 2 and the side battery 37 provided in the traveling structure 3. 1 part or the second part and the side battery 37 provided in the traveling structure 3.

[0230] Also, the vehicle body 2 has a third part that is relatively movable with respect to the second part, and the ducts 42, 43 are provided with a plurality of expansion joints in the portion disposed between the first part and the second part of the vehicle body 2 and the portion disposed between the second part and the third part of the vehicle body 2.

[0231] Incidentally, the forward duct 42 is a duct provided with a plurality of expansion and contraction parts 42c and 42d in a front - rear direction part arranged above the vehicle body side frame 22 and a left - right direction part arranged between the discharge manifold 41b and the vehicle body side frame 22.

[0232] On the other hand, the return duct 43 is a duct provided with a plurality of expansion and contraction parts 43c and 43d in a part arranged between the air - conditioner case 40 (first part) of the vehicle body 2 and the vehicle body center frame 21 (second part) which is a part of the vehicle body frame structure 20, and a part arranged between the vehicle body center frame 21 (second part) and the vehicle body side frame 22 (third part).

[0233] As described above, the ducts 42 and 43 may have a plurality of expansion and contraction parts in the part arranged between the first part and the second part of the vehicle body 2, or may have a plurality of such parts, and each of these parts may have an expansion and contraction part. The same applies to the part arranged between the second part and the third part.

[0234] Also, in the present embodiment, in the vehicle body 2, the parts that are relatively movably linked are three parts, namely the first to third parts. However, it is sufficient that there are at least three parts corresponding to such first to third parts, and even if there are four or more, the above - mentioned structure can be applied. Therefore, the expansion and contraction parts provided in such parts of the vehicle body 2 are not limited to two, such as the expansion and contraction parts 42c and 42d or the expansion and contraction parts 43d and 43d like the ducts 42 and 43, and may be provided according to the number of the corresponding parts.

[0235] Further, in the case where the work vehicle 1 includes a traveling structure 3 provided on the side of the vehicle body 2, an air conditioner unit 51 (cooling device) provided in an air conditioner case 40 (the first part of the vehicle body 2), and a side battery 37 (device to be cooled) disposed in the traveling structure 3 and cooled by a cooling medium supplied from the air conditioner unit 51, the return duct 43 extends in the front-rear direction from the air conditioner unit 51 to the vehicle body center frame 21 (the second part of the vehicle body 2) as a passage for the cooling medium, bends at the vehicle body center frame 21, extends in the left-right direction from the vehicle body center frame 21 to the vehicle body side frame 22 (the third part of the vehicle body 2), and extends in the vertical direction from the vehicle body side frame 22 to the side battery 37.

[0236] As can be seen in FIG. 2 and the like, since the first extension 43a of the return duct 43 on the vehicle body center frame 21 is piped immediately laterally inside the left and right of the vehicle body side frame 22, the supply duct 42 extends immediately upward to the outside of the vehicle body side frame 22 from the discharge manifold 41b, has a telescopic part 42d in the left-right direction at this outward extension part in the left-right direction, and the first extension 42a in the front-rear direction is piped immediately laterally outside the first extension 43a of the return duct 43. Since the supply duct 42 has a telescopic part 42c at this first extension 42a, the telescopic part 42c in the front-rear direction is behind the telescopic part 42d in the left-right direction. The supply duct 42 bends behind the telescopic part 42c in the front-rear direction and extends a second extension 42b in the left-right direction to the traveling structure 3, and has a telescopic part 42e in the vertical direction at the part extending across the traveling structure 3.

[0237] However, if the first extension 43a of the return duct 43 is moved closer to the inside in the left-right direction (the middle part in the left-right direction of the vehicle body center frame 21) than the position shown in FIG. 2, the first extension 42a of the supply duct 42 is also piped above the vehicle body center frame 21, inside the left and right of the vehicle body side frame 22. This is possible. In this case, similar to the piping route of the return duct 43 described above, the supply duct 42 as a passage for the cooling medium extends in the longitudinal direction from the air conditioner unit 51 to the vehicle body center frame 21 (the second part of the vehicle body 2), bends at the vehicle body center frame 21, and extends in the lateral direction from the vehicle body center frame 21 to the vehicle body side frame 22 (the third part of the vehicle body 2), and can be piped along a route that extends in the vertical direction from the vehicle body side frame 22 to the side battery 37.

[0238] As described above, the ducts 42 and 43 have expandable and contractible portions 42c to 42e and 43c to 43e, so that they can maintain a piped state without being disconnected between the air conditioner unit 51 and the side battery case 36 regardless of the deformation of the vehicle body 2 or the relative movement between the vehicle body 2 and the traveling structure 3.

[0239] In this way, in the work vehicle 1, a single duct 42 or 43 has a plurality of portions that span across separately positioned parts (such as the vehicle body 2 and the traveling structure 3, the vehicle body center frame 21 and the vehicle body side frame 22, etc.) that are relatively movable and linked, and these plurality of portions are provided with expandable and contractible portions. In the present embodiment, each duct 42 and 43 has three portions that span across separately positioned parts that are relatively movable and linked, and correspondingly has three expandable and contractible portions 42c to 42e and 43c to 43e. However, the present invention is not limited to this, and the number of expandable and contractible portions of each duct may exceed three or be less than three.

[0240] Also, the expansion and contraction direction of each expandable and contractible portion corresponds to the relative movement direction of the separately positioned parts across which the duct is spanned as described above. In the present embodiment, the relative movement directions of the parts across which the above three portions are spanned are different, and the expandable and contractible portions 42c and 43c of each duct 42 and 43 expand and contract in the longitudinal direction, the expandable and contractible portions 42d and 43d expand and contract in the lateral direction, and the expandable and contractible portions 42e and 43e expand and contract in the vertical direction, so that a single duct can expand and contract in various directions. However, the expansion and contraction directions of the plurality of expandable and contractible portions in a single duct are not limited to this, and for example, the plurality of expandable and contractible portions in a single duct may be able to expand and contract in the same direction.

[0241] That is, when each duct has a plurality of expansion / contraction parts, the number of the expansion / contraction parts and the expansion / contraction direction of the expansion / contraction parts correspond to what kind of structure is the structure for changing the vehicle shape of the above-described work vehicle 1, and also correspond to how each duct extends in a route corresponding to a cooling device (in this embodiment, the air conditioner unit 51) and a device to be cooled (in this embodiment, the side battery 37), and is not limited to the above-described embodiment.

[0242] In addition, instead of the expansion / contraction structure as described above, in preparation for the deformation of the vehicle body 2 and the relative movement between the vehicle body 2 and the traveling structure 3, the ducts 42 and 43 made of a flexible material are pre-bent, and for example, as the vehicle body 2 rises, the bent part is changed to a state of extending linearly. However, in this case, when the vehicle body 2 is not rising, the ducts 42 and 43 must be bent so as to bulge greatly from the vehicle body 2, and it is difficult to realize a compact piping.

[0243] In this regard, in the case of the ducts 42 and 43 according to the present embodiment, when the vehicle body 2 is not rising, the expansion / contraction parts 42e and 43e are not bent but are in a contracted state, so that the state along the vehicle body side frame 22 and the traveling frame 30 is maintained, and a compact piping can be realized.

[0244] The expansion / contraction parts 42c to 42e and 43c to 43e of the ducts 42 and 43 may be configured by, for example, a bellows hose, but are not limited thereto, and correspond to the relative movement between the center battery case 24 and the vehicle body frame structure 20, the relative movement between the vehicle body center frame 21 and the vehicle body side frame 22, and / or the relative movement between the vehicle body 2 and the traveling structure 3 as described above. As long as it has a structure that can expand and contract, it may be composed of any member.

[0245] Also, various considerations can be made regarding in which range and / or to what extent a telescopic part should be provided among the parts in each duct where the telescopic part should be provided. For example, when providing a telescopic part 43d that can expand and contract in the left-right direction corresponding to the relative movement between the vehicle body center frame 21 and the vehicle body side frame 22 in the left-right extending part 43b of the return duct 43, this telescopic part 43d is divided into a left-right outer part and a left-right inner part, and between these two parts serving as the telescopic part, a non-telescopic part of the return duct 43 may be interposed. Thereby, the axial length of each part as the telescopic part 43d becomes shorter, and it becomes possible to apply a short bellows hose to each of these parts.

[0246] Next, a second embodiment of the air-cooling system in the work vehicle 1 will be described with reference to FIGS. 15 to 16 and the like. Note that the description of the same configuration as that of the first embodiment will be omitted. Also, members and parts denoted by the same reference numerals as those used in the first embodiment have the same configuration or function as the corresponding members and parts of the first embodiment.

[0247] The air-cooling system shown in FIGS. 15 and 16 is applied to a work vehicle 1 including a cooling device, a first cooling target device and a second cooling target device cooled by cooling air discharged from the cooling device, a first cooling housing that houses the first cooling target device, and a second cooling housing that houses the second cooling target device. This is an embodiment of an air-cooling system having a structure in which an intake port for taking in air discharged from the second cooling housing after cooling the second cooling target device is provided in the first cooling housing.

[0248] That is, in this embodiment, the cooling device is an air-conditioning unit 51, the first cooling target device is a center battery 50, the first cooling housing is a center battery case 24, the second cooling target device is a side battery 37, the second cooling housing is a side battery case 36, and an intake port 24h for taking in air discharged from the side battery case 36 is provided in the center battery case 24.

[0249] However, as described in the above explanation of the duct structure, various types of cooling devices and equipment to be cooled are conceivable. Also, there are no restrictions on which of the multiple pieces of equipment to be cooled in the work vehicle 1 is designated as the first equipment to be cooled and which is designated as the second equipment to be cooled. For example, the side battery 37 may be designated as the first equipment to be cooled, the center battery 50 may be designated as the second equipment to be cooled, and an intake port may be provided in the side battery case 36 that houses the side battery 37 to take in the air discharged from the center battery case 24.

[0250] Alternatively, one of the first equipment to be cooled and the second equipment to be cooled may be the left side battery 37L, the other may be the right side battery 37R, and one of the first cooling housing and the second cooling housing may be the left side battery case 36L, the other may be the right side battery case 36R.

[0251] Alternatively, the first equipment to be cooled and / or the second equipment to be cooled may be something other than a battery.

[0252] In the present embodiment, inside the center battery case 24 (the first cooling housing), a cooling air passage 24c for directing the cooling air from the air conditioner unit 51 (the cooling device) onto the center battery 50 (the first equipment to be cooled) and an exhaust air passage 24d for discharging the air after cooling the center battery 50 to the air conditioner unit 51 are formed. The air from the side battery case 36 (the second cooling housing) introduced into the center battery case 24 through the intake port 24h merges with the air in the exhaust air passage 24d.

[0253] Also, inside the center battery case 24 (the first cooling housing), a first air guiding device for guiding air from the cooling air passage 24c to the exhaust air passage 24d and a second air guiding device for guiding air from the intake port 24h to the exhaust air passage 24d are provided. In the present embodiment, the first air guiding device is the fan 45 and the second air guiding device is the fan 46, but it is not limited to such fans. For example, simple plate materials or guide members such as ribs integrally formed with the housing may also be used.

[0254] Also, inside the center battery case 24 (first cooling housing), a partition plate is provided above the first equipment to be cooled. The space below the partition plate 24e in the center battery case 24 is the cooling air passage 24c, and the space above the partition plate 24e is the exhaust passage 24d.

[0255] Inside the center battery case 24 (first cooling housing), along the end of the partition plate 24e, a vertical communication passage 24g that connects the outlet of the cooling air passage 24c and the inlet of the exhaust passage 24d is provided. At the outlet of the cooling air passage 24c, a fan 45 (first air guiding device) that guides air from the cooling air passage 24c to the lower part of the communication passage 24g is provided. At the upper part of the communication passage 24g, an intake port 24h and a fan 46 (second air guiding device) that guides the air introduced from the intake port 24h to the inlet of the exhaust passage 24d are provided.

[0256] In the air-cooling system according to the second embodiment, the return duct 43 (left return duct 43L and right return duct 43R) for returning the cooling air after cooling the side battery 37 to the air conditioner unit 51 does not directly return the cooling air to the air conditioner unit 51 (suction manifold 76), but instead returns it into the center battery case 24, and is shorter compared to that of the first embodiment.

[0257] That is, as shown in FIG. 15, an intake port 24h is provided at the upper part of the rear end of the center battery case 24, and the outlet ends of the left return duct 43L and the right return duct 43R are connected to the intake port 24h. Note that a pair of intake ports 24h may be provided and the outlet ends of the left return duct 43L and the right return duct 43R may be respectively connected to the respective intake ports 24h, or the intake port 24h may be one, and the left return duct 43L and the right return duct 43R may be merged and then connected to the intake port 24h.

[0258] The air intake 24h faces the upper part of the communication passage 24g in the center battery case 24, that is, the inlet of the exhaust passage 24d. The air flow from the air intake 24h to the exhaust passage 24d is a linear horizontal flow, and the air is configured to flow smoothly from the air intake 24h to the exhaust passage 24d.

[0259] In this way, the cooling air (air) after cooling the left and right side batteries 37L and 37R is introduced from the left and right side battery cases 36L and 36R into the center battery case 24 through the left and right return ducts 43L and 43R, where it merges with the cooling air (air) after cooling the center battery 50 that has entered the communication passage 24g from the cooling air passage 24c and risen. Then, it is discharged from the cooling air outlet 24b through the exhaust passage 24d and returned to the air suction inlet 51a of the air conditioner unit 51.

[0260] In the center battery case 24, the exhaust passage 24d may be divided (separated) into a passage for air from the air intake 24h and a passage for air from the cooling air passage 24c, and the air passing through these passages may merge after exiting the cooling air outlet 24b and be inhaled into the air suction inlet 51a.

[0261] Regarding the division of the exhaust passage 24d, for example, a parallel partition plate may be provided above the partition plate 24e so as to divide the exhaust passage 24d into two upper and lower passages, and the rear end of this partition plate is connected to the rear end wall of the center battery case 24. The air intake 24h may be provided on the rear end wall of the center battery case 24 above this partition plate.

[0262] With the partition plate provided above the partition plate 24e in this way, the air after cooling the side battery 37 from the air intake 24h and the air after cooling the center battery 50 from the cooling air passage 24c are completely separated. The air after cooling the side battery 37 passes through the passage above the partition plate in the exhaust passage 24d, and the air after cooling the center battery 50 passes through the passage below the partition plate in the exhaust passage 24d and is discharged into the air conditioner chamber 40a from the cooling air outlet 24b.

[0263] Alternatively, the exhaust passage 24d may be divided into left and right passages, with one of the passages communicating with the intake port 24h to serve as a passage for the air after cooling the side battery 37, and the other passage communicating with the cooling air passage 24c to serve as a passage for the air after cooling the center battery 50.

[0264] Further, in the second embodiment, since the outlet ends of the left return duct 43L and the right return duct 43R are connected to the rear end portion of the center battery case 24, as can be seen in FIG. 16, in the first embodiment, the longitudinally extending portions 43a of the left return duct 43L and the right return duct 43R that were spanned on the vehicle body center frame 21 are omitted.

[0265] That is, in the first embodiment, the longitudinally extending portions 42a and 43a of the four ducts 42L, 42R, 43L, and 43R were piped in parallel on the upper portion of the vehicle body frame structure 20, whereas in the second embodiment, only the longitudinally extending portions 42a of the two ducts 42L and 42R are piped in parallel on the upper portion of the vehicle body frame structure 20 (the left and right vehicle body side frames 22L and 22R).

[0266] That is, in the second embodiment shown in FIGS. 15 and 16, the return duct 43 is a duct having a longitudinally extending portion (first longitudinally extending portion) 43a that extends from the air conditioner unit 51 (cooling device) to the side battery 37 (device to be cooled) and extends in the longitudinal direction (the first direction), and the longitudinally extending portion (first longitudinally extending portion) 42a of the supply duct 42 and the longitudinally extending portion (first longitudinally extending portion) 43a of the return duct 43 are arranged in parallel. However, in the vehicle body 2, a center battery 50 (second device to be cooled) that is cooled by the cooling air from the air conditioner unit 51 is provided separately from the side battery 37 (device to be cooled), and an exhaust passage 24d for discharging the cooling air after cooling the center battery 50 to the air conditioner unit 51 is formed in a center battery case 24 that is a housing for housing the center battery 50 (second device to be cooled). The return duct 43 is connected to the center battery case 24 and communicates with the exhaust passage 24d in the center battery case 24.

[0267] As the ducts are reduced in this way, a space for arranging devices other than the ducts is secured above the vehicle body frame structure 20. For example, in the first embodiment, it was necessary to attach the situation detection device 10 via the stay 10d straddling the extension portions 43a of the return ducts 43L and 43R. In the second embodiment, however, between the extension portions 42a of the left and right forward ducts 42L and 42R piped on the left and right vehicle body side frame members 22L and 22R, a wide area not covered by the ducts is secured on the upper end surface of the support member 23 provided directly below the vehicle body center frame 21. Therefore, the situation detection device 10 can be directly attached to the upper end surface of the support member 23 without providing a stay for straddling the ducts.

[0268] Also, in the present embodiment, inside the center battery case 24, in addition to the fan 45 provided in the first embodiment, a fan 46 is arranged at a position facing the intake port 24h above the communication passage 24g. The position of this fan 46 corresponds to the position through which the aforementioned linear horizontal air flow from the intake port 24h to the exhaust passage 24d passes. That is, the fan 46 is arranged so as to promote the linear horizontal air flow from the intake port 24h to the exhaust passage 24d.

[0269] The fan 46 sucks the air flowing into the center battery case 24 from the intake port 24h and discharges it to the upper part of the communication passage 24g and the rear end part of the exhaust passage 24d, thereby causing a forward airflow from the intake port 24h to the exhaust passage 24d. Thereby, the cooling air from the intake port 24h is made to merge with the flow of the cooling air from the cooling air passage 24c and guided to the cooling air outlet 24b.

[0270] In the first embodiment, since the outlet end of the return duct 43 was connected to the air conditioner case 40, it was preferable to have an air conditioner case 40 for housing the air conditioner unit 51. However, in the second embodiment, the outlet end of the return duct 43 is connected to the center battery case 24. Therefore, it is not always necessary to provide the air conditioner case 40, and various variations can be considered regarding the arrangement relationship between the center battery case 24 and the air conditioner unit 51.

[0271] For example, as shown in FIG. 17, an air conditioner case 40 different from the center battery case 24 may be discarded, and the air conditioner unit 51 may be provided in the center battery case 24. In this case, there is no cooling air outlet 24b for discharging the air that has passed through the exhaust passage 24d to the outside from the center battery case 24, and the air that has passed through the exhaust passage 24d is taken into the air inlet 51a of the air conditioner unit 51 inside the center battery case 24.

[0272] Also, as shown in FIG. 18, the air conditioner unit 51 may be arranged outside the center battery case 24, the air conditioner case 40 may be discarded, and the air inlet 51a of the air conditioner unit 51 may be directed to the outside air. In this case, the air that has passed through the exhaust passage 24d is discharged from the cooling air outlet 24b of the center battery case 24, mixed with the outside air, and taken into the air inlet 51a of the air conditioner unit 51.

[0273] Note that the center battery case 24 illustrated in FIGS. 10, 15, 17, and 18 described above has a configuration in which, inside, an exhaust passage 24d for discharging the cooling air after cooling the center battery 50 is provided separately from the cooling air passage 24c for blowing the cooling air against the center battery 50 as the equipment to be cooled.

[0274] Such a center battery case 24 may be replaced with, for example, a center battery case 24 having a configuration without an exhaust passage 24d (partition plate 24e constituting the same) as shown in FIG. 19.

[0275] Hereinafter, an air cooling system according to a third embodiment having the center battery case 24 shown in FIG. 19 and the air cooling duct structure shown in FIG. 20 will be described.

[0276] That is, the center battery case 24 in FIG. 19 is provided with a cooling air inlet 24a connected to the discharge manifold 41a at the front end, while the cooling air outlet 24b is provided at the rear end of the center battery case 24.

[0277] Inside the center battery case 24, there is no passage for a flow in a direction different from the cooling air that enters from the cooling air inlet 24a and flows rearward, such as the exhaust passage 24d. The air that flows into the center battery case 24 from the cooling air inlet 24a at the front end of the center battery case 24 flows backward in the entire amount over almost the entire area inside the center battery case 24 and is discharged from the cooling air outlet 24b at the rear end of the center battery case 24.

[0278] And, in order to return the cooling air after cooling the center battery 50 inside the center battery case 24 to the air suction inlet 51a of the air conditioner unit 51, outside the center battery case 24 a return duct 44 is provided.

[0279] The inlet end of the return duct 44 is connected to the cooling air outlet 24b at the rear end of the center battery case 24. Most of the return duct 44 is bridged so as to extend in the front-rear direction above the center battery case 24 and on the upper part of the vehicle body 2. That is, as shown in FIG. 20, the return duct 44 has an extension part 44a that extends in the front-rear direction in parallel with the extension parts 42a, 43a of the ducts 42, 43 from the front part of the vehicle body 2 to the front-rear middle part corresponding to the rear end part of the center battery case 24.

[0280] When applying the center battery case 24 and the return duct 44 shown in FIGS. 19 and 20 to the first embodiment having return ducts 43L, 43R that extend to, for example, the air conditioner case 40 that houses the air conditioner unit 51, it is preferable to arrange the extension part 44a of the return duct 44 between the left return duct 43L and the right return duct 43R on the vehicle body center frame 21.

[0281] Also, the front end part of the return duct 44 from the center battery case 24 is connected to the upper end part of the air conditioner case 40, similarly to the front end parts of the return ducts 43L, 43R from the side battery cases 36, and has a structure for discharging air into the space inside the air conditioner case 40.

[0282] Alternatively, as shown in FIG. 19, an intake manifold 51b communicating with the air intake port 51a may be provided at the front portion of the air conditioner unit 51, and the front ends (outlet ends) of the return ducts 43L, 43R, and 44 may be connected to the intake manifold 51b.

[0283] Also, as shown in FIG. 20, between the front end portion of the return duct 44 and the front end of the extension portion 44a on the vehicle body center frame 21, similar to the expansion and contraction portion 43c of the return duct 43, it is preferable to provide an expansion and contraction portion 44c that can expand and contract corresponding to the forward and backward movement of the center battery case 24.

[0284] That is, in the third embodiment, a center battery 50 cooled by the cooling air from the air conditioner unit 51 (cooling device) is provided on the vehicle body 2 separately from the side battery 37, and at least one duct 44 extending from the air conditioner unit 51 (cooling device) to the center battery 50 has an extension portion (first extension portion) 44a extending in the front-rear direction (first direction) in the range from the front end portion (first end portion) to the front-rear middle portion (middle portion) of the vehicle body 2.

[0285] Now, in the work vehicle 1, various forms of circuit structures for supplying the temperature-adjusting medium discharged from the temperature-adjusting device to the temperature-adjusting target equipment can be considered.

[0286] As the temperature-adjusting device, in addition to the air conditioner unit (air temperature-adjusting device) 51 as the above-described air-cooling device 110 (see FIG. 14) and the radiator 52 as the water-cooling device 120 (see FIG. 14), a heater or the like can be considered. As the temperature-adjusting medium, air, water, refrigerant gas, etc. can be considered.

[0287] As the temperature-adjusting target equipment, batteries such as the above-described center battery 50 and side battery 37, electrical equipment such as the above-described work system electric unit E1, hydraulic system electric unit E2, traveling system electric unit E3 (front traveling system electric unit E3F, rear traveling system electric unit E3R), and hydraulic equipment such as the control valve unit 27 can be considered.

[0288] When the battery is the device to be temperature-adjusted, as the medium for temperature adjustment, air as cooling air can be considered, and it can be cooled by an air-cooling device 110 such as an air conditioner unit 51. Note that the battery can also be cooled by the cooling water generated by the heat exchange action of the radiator 52 which is a water-cooling device 120.

[0289] When electrical equipment such as an electric motor or an inverter is the device to be temperature-adjusted, as the medium for temperature adjustment, cooling water can be considered, and it can be cooled by the cooling water generated by the radiator 52 as a water-cooling device 120.

[0290] Also, when hydraulic equipment such as a hydraulic pump 57 or various hydraulic actuators is the device to be temperature-adjusted, fins or the like are formed on the case housing such hydraulic equipment, and the case is cooled by the cooling air from the air conditioner unit 51 as the air-cooling device 110, or a water jacket is formed on the case, and the cooling water from the radiator 52 as the water-cooling device 120 is sent into the water jacket to cool the case, etc. can be considered.

[0291] Or, as an oil cooler for cooling the hydraulic oil supplied to the hydraulic pump 57 or the hydraulic actuator, or the lubricating oil replenished to each part of the work vehicle 1, for example, the air conditioner unit 51 as an air-cooling device or the radiator 52 as a water-cooling device, etc. can be used. Or, a temperature adjustment device as an oil cooler may be provided separately from the air conditioner unit 51 or the radiator 52.

[0292] Note that when a heater is used as the temperature adjustment device, as the medium for temperature adjustment, warm water heated by the heater, etc. can be considered. For example, when the place where the work vehicle 1 is used is a low-temperature area and the lubricating efficiency of lubricating oil, etc. decreases, circulating the warm water in the work vehicle 1 to warm the lubricating oil, etc. can be considered.

[0293] And when the vehicle structure is composed of a vehicle body 2 and left and right traveling structures 3L and 3R arranged on both the left and right sides of the vehicle body 2 as in the work vehicle 1 of the present application, several patterns can be considered as the structure of a temperature adjustment system for supplying the temperature adjustment medium generated by the temperature adjustment device to the temperature adjustment target devices D1, D2L, and D2R provided in the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R, respectively.

[0294] First, the temperature adjustment system TS1 shown in FIG. 21 will be described. The work vehicle 1 to which this temperature adjustment system TS1 is applied includes a vehicle body 2 and left and right traveling structures 3L and 3R provided on the left and right sides of the vehicle body 2. In the vehicle body 2, a first device D1 and a first adjustment device T1 for adjusting the temperature of the first device D1 are arranged. In one of the left and right traveling structures 3L and 3R, a second device D2L (or D2R) and a second adjustment device T2L (or T2R) for adjusting the temperature of the second device D2L (or D2R) are arranged. In the other of the left and right traveling structures 3L and 3R, a third device D2R (or D2L) and a third adjustment device T2R (or T2L) for adjusting the temperature of the third device D2R (or D2L) are arranged.

[0295] That is, the temperature adjustment system TS1 is an independent type temperature adjustment system in which each of the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R is provided with independent temperature adjustment devices T1, T2L, and T2R and temperature adjustment circuits C1, C2L, and C2R as independent closed circuits.

[0296] Regarding the first device D1, the second device D2L (or D2R), and the third device D2R (or D2L) that are the temperature adjustment targets in this independent type temperature adjustment system TS1, various things can be considered and are not limited. Also, each is not limited to a single device and may be composed of a plurality of devices.

[0297] For example, the first device D1 is a working system electric unit E1 (inverter 53 and electric motor 54), which is an electrical device for driving and controlling a working device connected to the vehicle body 2, and / or a hydraulic pump 57 or the like as a hydraulic device for controlling a hydraulic actuator equipped on the vehicle body 2. Further, the first device D1 may include a hydraulic system electric unit E2 (inverter 55 and electric motor 56) for driving the hydraulic pump 57.

[0298] Also, for example, the second device D2L (or D2R) and the third device D2R (or D2L) are traveling motors 7 (7F, 7R) for driving the wheels 5 (front wheels 5F, rear wheels 5R) of the respective traveling structures 3L, 3R.

[0299] Moreover, as the first adjustment device T1, the second adjustment device T2L (or T2R), and the third adjustment device T2R (or T2L) in this independent type temperature adjustment system TS1, various ones can be considered, and the device structure is not limited. Note that it is preferably a device corresponding to each of the first device D1, the second device D2L (or D2R), and the third device D2R (or D2L) which are the respective temperature adjustment targets.

[0300] For example, it is conceivable that at least one of the first adjustment device T1, the second adjustment device T2L (or T2R), and the third adjustment device T2R (or T2L) is a radiator for water cooling (water temperature adjustment), an air temperature adjustment device for air cooling (air temperature adjustment), or a heater for water temperature adjustment or the like.

[0301] Also, the first adjustment device T1, the second adjustment device T2L (or T2R), and the third adjustment device T2R (or T2L) may be provided at any position among the vehicle body 2 and the respective left and right traveling structures 3L, 3R.

[0302] Also, in the work vehicle 1 adopting the independent temperature adjustment system TS1, a first adjustment circuit C1 for circulating a temperature adjustment medium between the first adjustment device T1 and the first device D1 is provided in the vehicle body 2. On one traveling structure 3L (or 3R), a second adjustment circuit C2L (or C2R) for circulating a temperature adjustment medium between the second adjustment device T2L (or T2R) and the second device D2L (or D2R) is provided. On the other traveling structure 3R (or 3L), a third adjustment circuit C2R (or C2L) for circulating a temperature adjustment medium between the third adjustment device T2R (or T2L) and the third device D2R (or D2L) is provided.

[0303] As the first adjustment circuit C1, the second adjustment circuit C2L (or C2R), and the third adjustment circuit C2R (or C2L), various types are conceivable, and the device structure is not limited. Note that it is preferably a device corresponding to each temperature adjustment target, namely the first device D1, the second device D2L (or D2R), and the third device D2R (or D2L).

[0304] For example, at least one of the first adjustment device T1, the second adjustment device T2L (or T2R), and the third adjustment device T2R (or T2L) includes a radiator and a radiator fan, and the first adjustment circuit C1, the second adjustment circuit C2L (or C2R), and the third adjustment circuit C2R (or C2L) connected to the radiator may include a cooling water storage tank and a cooling water discharge pump.

[0305] The water-cooled cooling (temperature adjustment) system including the water-cooled cooling (temperature adjustment) circuit R1 for cooling the work system electric unit E1 in the vehicle body 2 and the water-cooled cooling (temperature adjustment) circuit R2 for cooling the hydraulic system electric unit E2 shown in FIG. 12, and the water-cooled cooling (temperature adjustment) circuits R3F for cooling the front traveling system electric unit E3F and R3R for cooling the rear traveling system electric unit E3R provided for each traveling structure 3 shown in FIG. 13 in the above-described work vehicle 1 is an application example of the independent temperature adjustment system TS1.

[0306] In the embodiment provided with the water-cooled cooling (temperature adjustment) circuits R1, R2, R3L, and R3R shown in FIGS. 12 and 13 above, the first device D1 is the working system electric unit E1 and / or the hydraulic pump such as 57, and corresponding to the second device D2L (or D2R) and the third device D2R (or D2L) being the traveling motors 7 (7F, 7R), all of the first adjustment device T1, the second adjustment device T2L (or T2R), and the third adjustment device T2R (or T2L) are radiators (radiators 52, 71).

[0307] The first adjustment device T1 includes the radiator 52 and the radiator fan 52a, the second adjustment device T2L (or T2R), and the third adjustment device T2R (or T2L) each include the radiator 71 and the radiator fan 71a, the first adjustment circuit C1 includes the reservoir (for storing cooling water) tank 59 and the electric cooling water (for discharging cooling water) pump 58, and the second adjustment circuit C2L (or C2R) and the third adjustment circuit C2R (or C2L) each include the reservoir (for storing cooling water) tank 73 and the electric cooling water (for discharging cooling water) pump 72.

[0308] As shown in FIGS. 1 to 6 etc., the left and right traveling structures 3L, 3R each have wheels 5, and the second adjustment device T2L (or T2R) and the third adjustment device T2R (or T2L) are each arranged so as to face the ground contact surface of the wheels 5 of the traveling structures 3L, 3R.

[0309] Furthermore, the second adjustment device T2L (or T2R) and the third adjustment device T2R (or T2L) are radiators 71, and each is inclined in the front-rear direction in front of the wheel 5 (front wheel 5F).

[0310] In addition, in Fig. 21, a radiator 52 and a radiator fan 52a are provided for the temperature adjustment device T1 in the vehicle body 2, an electric motor 54 etc. as a working system electric unit E1 and an electric motor 56 etc. as a hydraulic system electric unit E2 are provided for the temperature adjustment target device D1, a water-cooled cooling (temperature adjustment) circuit R1 is provided for the temperature adjustment circuit C1, a radiator 71 and a radiator fan 71a are provided for the temperature adjustment devices T2L, T2R in the left and right traveling structures 3L, 3R, and a traveling system electric unit E3 (E3FL, E3FR, E3RL, E3RR), that is, a front traveling motor 7F and a rear traveling motor 7R etc. are provided for the temperature adjustment target devices D2L, D2R. The application example of the independent type temperature adjustment system TS1 is shown when water-cooled cooling (temperature adjustment) circuits R2L, R2R are applied to the temperature adjustment circuits C2L, C2R.

[0311] The temperature adjustment system TS2 shown in Fig. 22 has a temperature adjustment device T3 provided in any one of the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R (in this embodiment, it is provided in the vehicle body 2, but it may be provided in any one). A temperature adjustment circuit C3 is provided for supplying the temperature adjustment medium from the temperature adjustment device T3 to the temperature adjustment target devices D1, D2L, D2R provided in the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R.

[0312] The temperature adjustment circuit C3 has a branch circuit that branches into the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R. Inside the vehicle body 2, a branch temperature adjustment circuit C3a is provided for supplying the temperature adjustment medium from the temperature adjustment device T3 to the temperature adjustment target device D1 provided in the vehicle body 2. Inside the left traveling structure 3L, a branch temperature adjustment circuit C3b is provided for supplying the temperature adjustment medium from the temperature adjustment device T3 to the temperature adjustment target device D2L provided in the left traveling structure 3L. Inside the right traveling structure 3R, a branch temperature adjustment circuit C3c is provided for supplying the temperature adjustment medium from the temperature adjustment device T3 to the temperature adjustment target device D2R provided in the right traveling structure 3R.

[0313] The cooling medium discharged from the temperature adjustment device T3 (various types are conceivable, similar to the temperature adjustment system TS1) passes through the common medium supply passage C3d and then branches into the branch temperature adjustment circuits C3a, C3b, and C3c. While circulating around each of the branch temperature adjustment circuits C3a, C3b, and C3c, it cools the respective temperature adjustment target devices D1, D2L, and D2R (sequentially if there are multiple devices). Eventually, it returns to the confluence point to the common medium return passage C3e, and the confluent medium passes through the medium return passage C3e and is returned to the temperature adjustment device T3 to undergo the temperature adjustment effect again. This is the flow that undergoes the temperature adjustment effect.

[0314] That is, the temperature adjustment system TS2 is a branched type temperature adjustment system provided with a temperature adjustment circuit C3 that branches the branch temperature adjustment circuits C3a, C3b, and C3c from one temperature adjustment device T3 to the temperature adjustment target devices D1, D2L, and D2R provided in the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R respectively.

[0315] In addition, in the temperature adjustment circuit C3 of the temperature adjustment system TS2 in FIG. 22, it is structured to branch into the branch temperature adjustment circuits C3a, C3b, and C3c via the common medium supply passage C3d extending from the discharge port of the temperature adjustment device T3. However, it is not limited to this, and it may also be structured to branch directly into the branch temperature adjustment circuits C3a, C3b, and C3c from the discharge port of the temperature adjustment device T3.

[0316] Also, in FIG. 22, the position where the temperature adjustment circuit C3 branches from the common medium supply passage C3d into the branch temperature adjustment circuits C3a, C3b, and C3c is at the rear part of the vehicle body 2. However, it is not limited to this, and it may be branched from the common medium supply passage C3d into the branch temperature adjustment circuits C3a, C3b, and C3c at any position of the work vehicle 1.

[0317] In addition, the temperature adjustment circuit C3 in the temperature adjustment system TS2 of FIG. 22 has a structure in which the media flowing through the branch temperature adjustment circuits C3a, C3b, and C3c are collected (merged) in a common media return passage C3e extending from the suction port of the temperature adjustment device T3 and then returned to the suction port of the temperature adjustment device T3. However, the present invention is not limited to this, and the media outlets of the respective branch temperature adjustment circuits C3a, C3b, and C3c may be directly connected to the suction port of the temperature adjustment device T3.

[0318] Also, in FIG. 22, the position where the temperature adjustment circuit C3 collects the cooling (temperature adjustment) media flowing through the branch temperature adjustment circuits C3a, C3b, and C3c and merges them into the common media return passage C3e is at the rear part of the vehicle body 2. However, the present invention is not limited to this, and the branch temperature adjustment circuits C3a, C3b, and C3c may be merged into the common cooling (temperature adjustment) media return passage C3e at any position of the work vehicle 1.

[0319] That is, the work vehicle 1 to which the branch-type temperature adjustment system TS2 of FIG. 22 is applied includes a vehicle body 2, a left traveling structure 3L provided on the left side of the vehicle body 2, a right traveling structure 3R provided on the right side of the vehicle body 2, a temperature adjustment device T3 disposed on any one of the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R, and devices whose temperatures are adjusted by the temperature adjustment device T3, including a first device D1 disposed on the vehicle body 2, a second device D2L disposed on the left traveling structure 3L, and a third device D2R disposed on the right traveling structure 3R, which are temperature adjustment target devices D1, D2L, D2R, and a temperature adjustment circuit C3 that sends a temperature adjustment medium from the temperature adjustment device T3 to the temperature adjustment target devices D1, D2L, D2R. The temperature adjustment circuit C3 branches from the temperature adjustment device T3 and is connected to the first device D1, the second device D2L, and the third device D2R, respectively.

[0320] Regarding the first device D1, the second device D2L (or D2R), and the third device D2R (or D2L) that are temperature adjustment targets in this branch-type temperature adjustment system TS2, various things can be considered and are not limited. Also, each is not limited to a single device and may be composed of a plurality of devices.

[0321] For example, in the work vehicle 1 shown in FIGS. 1 to 14, etc., the center battery 50, the work system electric unit E1 (inverter 53 and electric motor 54), the work system electric unit E1 (inverter 55 and electric motor 56), and / or hydraulic equipment such as the hydraulic pump 57, etc. can be considered as the first device D1, and the side battery 37, the front traveling system electric unit E3F (inverter 6F and traveling motor 7F), and / or the rear traveling system electric unit E3R (inverter 6R and the traveling motor 7R) can be considered as the second devices D2L and / or D2R.

[0322] Also, as the adjustment device T3 in this branched type temperature adjustment system TS2, various ones can be considered and the device structure is not limited. Note that it is preferably a device corresponding to the first device D1, the second device D2L (or D2R), and the third device D2R (or D2L) which are the temperature adjustment target devices.

[0323] For example, when at least one of the first device D1, the second device D2L (or D2R), and the third device D2R (or D2L) as the cooling target device is a battery, the adjustment device T3 can be an air temperature adjustment device and the battery can be cooled by the cooling air discharged therefrom, or the adjustment device T3 can be a radiator and a radiator fan, and the battery can be cooled by the cooling water generated by the heat exchange of the radiator and the radiator fan.

[0324] Note that when constructing a water-cooled branched type temperature adjustment system TS2 in the work vehicle 1 with the adjustment device T3 as a radiator and a radiator fan, the radiator as the adjustment device T3 can be the radiator 52 and the radiator fan 52a of the vehicle body 2, or can be the radiator 71 and the radiator fan 71a provided on either one of the left traveling structure 3L and the right traveling structure 3R.

[0325] Also, the positions of the radiator and the radiator fan as the adjustment device T3 are not limited to the positions of the radiators 52 and 71 and the radiator fans 52a and 71a as shown in FIGS. 1 to 9 and the like, and may be other positions suitable for circulating the cooling water among the first device D1, the second device D2L (or D2R), and the third device D2R (or D2L).

[0326] Also, regarding the capacity (size) of the radiator as the adjustment device T3, in consideration of supplying the cooling water to the first device D1, the second device D2L (or D2R), and the third device D2R (or D2L), it may be larger than each of the adjustment devices T1, T2L, and T2R in the independent temperature adjustment system TS1 and is not limited.

[0327] Also, the temperature adjustment circuit C3 in the branched temperature adjustment system TS2 includes a first temperature adjustment circuit C3a that circulates the temperature adjustment medium between the temperature adjustment device T3 and the first device D1, a second temperature adjustment circuit C3b that circulates the temperature adjustment medium between the temperature adjustment device T3 and the second device D2L (or D2R), and a third temperature adjustment circuit C3c that circulates the temperature adjustment medium between the temperature adjustment device T3 and the third device D2R (or D2L).

[0328] As described above, when the branched temperature adjustment system TS2 applied to the work vehicle 1 is a water-cooling system using the radiator as the adjustment device T3, the first temperature adjustment circuit C3a that supplies the cooling water to, for example, the working system electric unit E1 (such as the electric motor 54) and the hydraulic system electric unit E2 (such as the electric motor 56) as the first device D1 is preferably provided with a pair of cooling water discharge pumps 58 for discharging the cooling water to each of the working system electric unit E1 (such as the electric motor 54) and the hydraulic system electric unit E2 (such as the electric motor 56), and at least one cooling water storage (reservoir) tank 59.

[0329] Also, in this case, as each of the second device and the third devices D2L and D2R, for example, in each of the second temperature adjustment circuit C3b and the third temperature adjustment circuit C3c that supply cooling water to the front traveling system electric unit E3F (such as the front traveling motor 7F) and the rear traveling system electric unit E3R (such as the rear traveling motor 7R), a pair of cooling water discharge pumps 72 for discharging cooling water to each of the front traveling system electric unit E3F (such as the front traveling motor 7F) and the rear traveling system electric unit E3R (such as the rear traveling motor 7R), and at least one cooling water storage (reservoir) tank 73 are preferably provided.

[0330] In addition, the air-cooled cooling (temperature adjustment) system that supplies the cooling air from one air conditioner unit 51 to the center battery 50 in the vehicle body 2 and the side batteries 37 provided for each of the left and right traveling structures 3 in the above-described work vehicle 1 is one application example of the branched type temperature adjustment system TS2.

[0331] The cooling air passage 24c and the exhaust passage 24d in the center battery case 24 shown in FIG. 10 in the air-cooling system according to the above-described first embodiment correspond to the first temperature adjustment circuit C3a that circulates air between the air conditioner unit 51 and the center battery 50 as the first device D1. The left forward duct 42L, the left side battery case 36L, and the left return duct 43L shown in FIGS. 1 to 10 and the like correspond to the second temperature adjustment circuit C3b (or the third temperature adjustment circuit C3c) that circulates air between the air conditioner unit 51 and the left side battery case 36L as the second device D2L. The right forward duct 42R, the right side battery case 36R, and the right return duct 43R correspond to the third temperature adjustment circuit C3c (or the second temperature adjustment circuit C3b) that circulates air between the air conditioner unit 51 and the right side battery case 36R as the third device D2R.

[0332] Note that, in the air-cooling system according to this first embodiment, the cooling air passages 24c, the left forward duct 42L, and the right forward duct 42R corresponding to the passage portions from the air outlets (discharge manifolds 41a and 41b) of the air conditioner unit 51 to the first to third devices of the first to third temperature adjustment circuits C3a, C3b, and C3c respectively branch off immediately from the air outlets. Further, the exhaust passages 24d, the left return duct 43L, and the right return duct 43R corresponding to the passage portions from the first to third devices of the first to third temperature adjustment circuits C3a, C3b, and C3c remain separated from each other (without merging), and their terminal ends are directly connected to the air conditioner unit 51 (such as the air conditioner case 40 that houses the unit).

[0333] However, even in the air-cooling system of the first embodiment, as shown in FIG. 22, common medium passages (confluence passages) C3d and C3e, which are passages integrating the temperature adjustment circuits C3a, C3b, and C3c that are branch circuits, may be provided. Further, regarding the integration (confluence) of such medium passages, it is not necessary to integrate all three temperature adjustment circuits C3a, C3b, and C3d, and any two of them may be integrated instead.

[0334] For example, the forward ducts 42L and 42R shown in FIG. 2 etc. (corresponding to the passage portions up to the second device D2L (or D2R) and the third device D2R (or D2L) in the second temperature adjustment circuit C3b and the third temperature adjustment circuit C3c) may be integrated into a single forward duct so as to correspond to a common cooling (temperature adjustment) medium passage (confluence passage) C3d in the range from the air conditioner unit 51 (discharge manifold 41b) at the front end of the vehicle body 2 to the rear end of the first extension portion 42a (the location where it bends to the second extension portion 42b).

[0335] Also, the return ducts 43L and 43R shown in FIG. 2 etc. (corresponding to the passage portions of the medium after passing through the second and third devices in the second temperature adjustment circuit C3b and the third temperature adjustment circuit C3c) may be integrated into a single return duct so as to correspond to a common medium return passage (confluence passage) C3e in the range from the air conditioner unit 51 (air suction port 51a) to the rear end of the first extension portion 43a (the location where it bends to the extension portion 43b).

[0336] Also, in the air-cooling system according to the second embodiment shown in FIGS. 15 and 16, the exhaust passage 24d in the center battery case 24 corresponds to the communication passage 24g corresponding to the passage after passing through the first device D1 of the first temperature adjustment circuit C3a, and the return ducts 43L and 43R corresponding to the passages after passing through the second device D2L (or D2R) and the third device D2R (or D2L) of the second temperature adjustment circuit C3b and the third temperature adjustment circuit C3c are integrated passages, which corresponds to the medium return passage D3e shown in FIG. 22. It corresponds to.

[0337] As described above, the exhaust passage 24d may be divided into the passage of air from the intake port 24h and the passage of air from the cooling air passage 24c. In this case, the first temperature adjustment circuit C3a including the cooling air passage 24c and the communication passage 24g is provided up to the air intake port 51a of the air conditioner unit 51 while being separated from the second temperature adjustment circuit C3b and the third temperature adjustment circuit C3c. On the other hand, the passages after passing through the second device D2L (or D2R) and the third device D2R (or D2L), which are the return ducts 43L and 43R, are integrated (merged) into the passage portion of the divided exhaust passage 24d that communicates with the intake port 24h.

[0338] The temperature adjustment system TS3 shown in FIG. 23 is provided with a temperature adjustment device T4 on any one of the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R (in this embodiment, it is provided on the vehicle body 2, but it may be provided on any of them). The temperature adjustment medium from the temperature adjustment device T4 sequentially circulates through the temperature adjustment target device D1 of the vehicle body 2, the temperature adjustment target device D2L of the left traveling structure 3L, and the temperature adjustment target device D2R of the right traveling structure 3R (in this embodiment, it is in the order of the temperature adjustment target device D2R of the right traveling structure 3R, the temperature adjustment target device D1 of the vehicle body 2, and the temperature adjustment target device D2L of the left traveling structure 3L, but any order may be used). The temperature adjustment circuit C4 is configured as a single circulation circuit that connects the temperature adjustment target devices D1, D2L, and D2R in series throughout the work vehicle 1.

[0339] Next, the configuration of the control system in the work vehicle 1 will be described with reference to FIG. 14. As shown in FIG. 14, the work vehicle 1 is equipped with a positioning device 11. The positioning device 11 can detect the position of the vehicle body 2 (positioning information including latitude and longitude) by a satellite positioning system (positioning satellite) such as D-GPS, GPS, GLONASS, Beidou, Galileo, or Michibiki. That is, the positioning device 11 receives satellite signals (position of the positioning satellite, transmission time, correction information, etc.) transmitted from the positioning satellite and detects the position of the vehicle body 2 (for example, latitude and longitude) based on the satellite signals.

[0340] The positioning device 11 includes a receiving device 12 and an inertial measurement unit (IMU) 13. The receiving device 12 is a device that has an antenna or the like and receives satellite signals transmitted from the positioning satellite, and is attached to the vehicle body 2. The inertial measurement unit 13 includes an acceleration sensor that detects acceleration, a gyro sensor that detects angular velocity, and the like. The inertial measurement unit 13 is attached to the vehicle body 2. The inertial measurement unit 13 can detect the roll angle, pitch angle, yaw angle, etc. of the vehicle body 2. Note that the yaw angle may also be detected by installing a plurality of positioning devices 11.

[0341] As shown in FIG. 14, the work vehicle 1 is equipped with a communication device 14. The communication device 14 includes a communication circuit for performing communication via an in-vehicle network and a wireless communication circuit for performing wireless communication. The wireless communication circuit can communicate wirelessly directly or indirectly with an external device by a communication standard such as Wi-Fi (Wireless Fidelity, registered trademark) of the IEEE802.11 series, BLE (Bluetooth (registered trademark) Low Energy), LPWA (Low Power, Wide Area), LPWAN (Low-Power Wide-Area Network), etc.

[0342] As another example, for instance, a communication circuit capable of wireless communication with an external device may be provided in the communication device 14 via a mobile phone communication network, a data communication network, or the like. The external device is, for example, a personal computer, a smartphone, a tablet computer, a PDA, or a server, etc.

[0343] As shown in FIGS. 1 to 6 and the like, the work vehicle 1 includes at least one situation detection device 10 that detects the situation around the work vehicle 1 so that, for example, it starts after confirming the surrounding safety.

[0344] The situation detection device 10 has a camera (imaging device) 10a, a sensor 10b, and a calculation unit 10c (see FIG. 14). In the case of this embodiment, the situation detection device 10 includes both the camera 10a and the sensor 10b, but it may include only one of them.

[0345] The camera 10a is composed of, for example, a CCD camera equipped with a CCD (Charge Coupled Devices) image sensor, a CMOS camera equipped with a CMOS (Complementary Metal Oxide Semiconductor) image sensor, or the like.

[0346] The camera 10a images the surroundings of the work vehicle 1 and generates an image signal. The calculation unit 10c is composed of a computer or the like including a signal processing circuit that processes the generated image signal. The signal processing circuit detects the state of the object (such as the presence or absence of the object, the position of the object, the type of the object, the size of the object, etc.) based on the image signal output from the camera 10a.

[0347] The sensor 10b is an optical sensor and is composed of, for example, a LiDAR (Light Detection And Ranging).

[0348] The lidar (laser sensor) irradiates pulsed measurement light (laser light) millions of times per second from a light source such as a laser diode, and scans horizontally or vertically by reflecting the measurement light with a rotating mirror, and projects it onto a predetermined detection range (sensing range).

[0349] Then, the lidar receives the reflected light of the measurement light by the object with a light receiving element. The signal processing circuit of the calculation unit 10c detects the state of the object (presence or absence of the object, position of the object, type of the object, size of the object, etc.) based on the light reception signal output from the light receiving element of the lidar.

[0350] Also, the signal processing circuit detects the distance to the object based on the time from when the measurement light is irradiated by the lidar until the reflected light is received (TOF (Time of Flight) method). Note that the method for detecting the distance by the lidar may be a method other than the TOF method.

[0351] As described above, the optical sensor 10b may be provided with, for example, an auxiliary acoustic sensor to improve the detection accuracy.

[0352] The acoustic sensor is composed of, for example, an airborne ultrasonic sensor such as a sonar. The airborne ultrasonic sensor transmits a measurement wave (ultrasonic wave) to a predetermined detection range by a transmitter, and receives the reflected wave of the measurement wave reflected by the object with a receiver. The signal processing circuit detects the state of the object (presence or absence of the object, position of the object, type of the object, size of the object, etc.) based on the signal output from the receiver.

[0353] Also, the signal processing circuit detects the distance to the object based on the time from when the measurement wave is transmitted by the airborne ultrasonic sensor until the reflected wave is received (TOF (Time of Flight) method). Note that the method for detecting the distance by the acoustic sensor may be a method other than the TOF method.

[0354] The situation detection device 10 detects the situation around the work vehicle 1 (the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R). The situation detection device 10 detects, as the situation around the work vehicle 1, obstacle information indicating whether there are any obstacles or people in the vicinity of the work vehicle 1 that may come into contact.

[0355] The situation detection device 10 detects, as the situation around the work vehicle 1, road information which is information about the road on which the left and right traveling structures 3 can travel. Specifically, it detects road information which is a value related to the road on which the traveling structure 3 can travel. The situation detection device 10 detects, as road information, for example, the width of the traveling road.

[0356] The width of the traveling road detected by the situation detection device 10 is the width of the object that the work vehicle 1 attempts to straddle and travel between the left traveling structure 3L and the right traveling structure 3R. The situation detection device 10 detects, as the width of the traveling road, for example, the width of the ridges provided on the ground, or the width of the obstacles existing on the ground that impede travel.

[0357] Also, the situation detection device 10 detects, as road information, for example, the height of the traveling road. The height of the traveling road detected by the situation detection device 10 is the height of the object that the vehicle body 2 attempts to straddle and travel between the left traveling structure 3L and the right traveling structure 3R. The situation detection device 10 detects, as the height of the traveling road, for example, the height of the ridges provided on the ground, or the height of the obstacles existing on the ground that impede travel.

[0358] The obstacles that impede travel are, for example, grooves or holes formed on the ground, crops planted on the ground, obstacles on the ground (for example, stones or artificial installations), etc. Typically, the situation detection device 10 can detect the height of the crops planted on the ground as the height of the obstacle.

[0359] The height of the crop detected by the situation detection device 10 is the height from the ground where the wheel 5 of the traveling structure 3 touches the ground to the upper end of the crop. For example, when the crop is planted in ridges, since the wheel 5 of the traveling structure 3 touches the ground between the ridges rather than on the ridges, the height of the crop detected by the situation detection device 10 is "the height of the crop itself + the height of the ridge".

[0360] The situation detection device 10 may detect the inclination in the left - right direction of the ground as the situation around the work vehicle 1. In this case, the situation detection device 10 can detect the height of the ground on which the left traveling structure 3L travels and the height of the ground on which the right traveling structure 3R travels as the situation around the work vehicle 1. Therefore, the situation detection device 10 may be mounted on each of the left traveling frame 30L and the right traveling frame 30R.

[0361] Also, in this case, as the situation detection device 10, for example, an inclination sensor that detects the inclination in the left - right direction of the work vehicle 1 (vehicle body 2) can be used. Also, a camera 10a may be used as the situation detection device 10, and the calculation unit 10c may be configured to detect the inclination in the left - right direction of the ground based on the image captured by the camera 10a.

[0362] Furthermore, in addition to the situation detection device 10 that detects the situation around the work vehicle 1, the work vehicle 1 is provided with a detection device that detects the state of the work vehicle 1 itself.

[0363] In FIG. 14, as a detection device that detects the state of the work vehicle 1 itself, a distance detection device 16 that detects the left - right direction distance between the left traveling structure 3L and the right traveling structure 3R corresponding to the vehicle width, which is the distance between the left and right wheels 5, and a vehicle height detection device 17 that detects the vehicle height, which is the vertical distance from the ground contact point of the wheel 5 to the lowest part of the vehicle body 2, are illustrated. In addition, it is conceivable that a rotation speed detection device that detects the rotation speed of the electric motor 54, a rotation speed detection device that detects the rotation speed of the wheel 5, etc. are provided.

[0364] As shown in FIG. 14, the control device 15 provided in the work vehicle 1 is a device that performs various controls of the work vehicle 1. The control device 15 includes an arithmetic unit (such as a CPU) and a storage unit (such as a RAM and a ROM). The storage unit may include an external memory provided outside the control device 15. The control device 15 is connected to various devices and mechanisms shown in FIG. 14 via an in-vehicle LAN (in-vehicle network) such as a CAN (Controller Area Network) or a communication line.

[0365] The control device 15 controls the operations of various devices and mechanisms communicably connected to the control device 15 by the arithmetic unit executing various control programs stored in the storage unit.

[0366] The control device 15 has control units such as an automatic driving control unit 15A, a distance change control unit 15B, a height change control unit 15C, and a position change control unit 15D. The functions of these control units are realized by the arithmetic unit executing a predetermined control program stored in the storage unit.

[0367] The automatic driving control unit 15A of the control device 15 controls the automatic driving of the work vehicle 1. The automatic driving control unit 15A is capable of executing line-type automatic driving control and autonomous automatic driving control.

[0368] In the line-type automatic driving control, the automatic driving control unit 15A controls the inverter 6 for output control of the traveling motor 7 of each wheel unit 4 so that the work vehicle 1 (vehicle body 2) moves along a preset planned traveling line, controls the rotational speed of the corresponding wheel 5, and controls each control valve in the control valve unit 27 for controlling the extension amount of the steering cylinder 35 of each wheel unit 4 to control the direction (steering angle) of the corresponding wheel 5.

[0369] In the autonomous automatic driving control, based on the result of detecting the position of the work vehicle 1 (vehicle body 2) by the positioning device 11, the automatic driving control unit 15A performs settings such as the traveling direction (steering direction) and vehicle speed (speed) of the vehicle body 2, and controls the inverter 6 for output control of the traveling motor 7 of each wheel unit 4 so as to achieve the set steering angle (direction) and vehicle speed, thereby controlling the rotational speed of the corresponding wheel 5. Also, the control valve unit 27 (control valve) for controlling the extension amount of the steering cylinder 35 of each wheel unit 4 is controlled to control the direction (steering angle) of the corresponding wheel 5.

[0370] Note that the line-type automatic driving control and the autonomous automatic driving control may be switchable by a switch or the like. Also, the automatic driving control unit 15A may be configured to be capable of executing either one of the line-type automatic driving control and the autonomous automatic driving control. Note that the configuration of the automatic driving control unit 15A is not limited to the above-described configuration.

[0371] Furthermore, based on the obstacle information obtained by the situation detection device 10 sensing (detecting an object) the surroundings of the work vehicle 1, the automatic driving control unit 15A determines whether the stopped work vehicle 1 should start, whether the traveling work vehicle 1 should stop, or whether it should steer to change the traveling direction, or whether the drive of the working device during work should be stopped, and / or whether the working device should be raised, etc., and controls the inverter 6 for output control of the traveling motor 7 in the traveling structure 3, the steering cylinder 35, the inverter 53 for output control of the electric motor 54 in the working system electric unit E1, the inverter 55 for output control of the electric motor 56 in the hydraulic system electric unit E2, etc. to realize the determined state.

[0372] As described above, since the control device 15 of the work vehicle 1 includes the automatic driving control unit 15A, the work vehicle 1 can perform automatic driving (driverless driving) without the operator boarding. Therefore, the work vehicle 1 of the illustrated embodiment does not have a driver's seat for the operator to sit on.

[0373] However, the work vehicle 1 may be a vehicle on which an operator rides and performs automatic driving. Alternatively, the work vehicle 1 may be a vehicle on which an operator rides and drives to perform driving. When the work vehicle 1 is a vehicle on which an operator rides, a driver's seat is provided on the vehicle body 2.

[0374] Based on information regarding the width of the traveling road included in the road information acquired by the detection of the situation detection device 10, information regarding the distance between the left traveling structure 3L and the right traveling structure 3R detected by the distance detection device 16, etc., the distance change control unit 15B of the control device 15 makes the distance between the left traveling structure 3L and the right traveling structure 3R correspond to the width of the traveling road where the distance is detected, that is, so that the left and right wheels 5 are correctly arranged in the furrow, the control valve unit 27 (control valve) for controlling the expansion and contraction of the width change cylinder 8A and / or Or the width change cylinder 8B is controlled.

[0375] Based on information regarding the height of the traveling road included in the road information acquired by the detection of the situation detection device 10, information regarding the vehicle height detected by the vehicle height detection device 17, etc., the height change control unit 15C of the control device 15 makes the vehicle height, which is the vertical distance from the ground contact point of the wheel 5 to the bottom end of the vehicle body 2, correspond to the height of the detected traveling road, that is, so that the vehicle body 2 straddles crops growing on the traveling road, the control valve unit 27 (control valve) for controlling the expansion and contraction of the vehicle body lifting cylinder 9 as the vehicle body moving device is controlled.

[0376] Further, based on information regarding the left - right inclination of the ground acquired by the detection of the situation detection device 10, etc., the height change control unit 15C of the control device 15 adjusts the left - right inclination of the vehicle body 2. To adjust the difference in the piston rod extension amounts of the left vehicle body lifting cylinder 9L and the right vehicle body lifting cylinder 9R as the vehicle body moving device, the control valve unit 27 (control valve) for controlling the expansion and contraction of the left vehicle body lifting cylinder 9L and the right vehicle body lifting cylinder 9R is controlled.

[0377] Further, the position change control unit 15D of the control device 15 measures the slip ratios of the front wheels 5F and the rear wheels 5R from, for example, the detection results of a rotational speed detection device that detects the rotational speed of the wheels 5. For example, if the slip ratio of the front wheels 5F is high, it is conceivable to cause an external device to display a warning to move the center battery case 24 forward via the communication device 14.

[0378] Also, when the work vehicle 1 is provided with a battery moving actuator 81 (vehicle body deformation device 80) for moving the center battery case 24 back and forth as shown in FIG. 14, the position change control unit 15D operates the battery moving actuator 81 to move the center battery case 24 (when the battery moving actuator 81 is a hydraulic actuator, the corresponding control valve is controlled).

[0379] Furthermore, the work vehicle 1 is provided with one or more temperature detection devices 18, and the control device 15 effectively cools (temperature-adjusts) the center battery 50, the left and right side batteries 37L, 37R, etc. as cooling (temperature-adjustment) targets, the work system electric unit E1, the hydraulic system electric unit E2, and the traveling system electric units E3 (E3F, E3R), etc. of electrical equipment, and hydraulic equipment such as the control valve unit 27 by controlling the outputs of the air conditioner unit 51 which is an air-cooling (air-conditioning) device 110, the radiator fans 52a, 71a, etc. which are water-cooling devices 120 based on the detection results of the temperature detection devices 18.

[0380] The actions or effects of each component of the work vehicle 1 described above will be described below.

[0381] (Item A1) The work vehicle 1 includes a vehicle body 2, a cooling device (air conditioner unit 51) provided on the vehicle body 2, at least one device to be cooled (batteries 37, 50) cooled by cooling air discharged from the cooling device (air conditioner unit 51), and a plurality of ducts 42, 43, 44 for allowing the cooling air to flow between the cooling device (air conditioner unit 51) and the device to be cooled. The vehicle body 2 has a first end portion and a second end portion (front end portion and rear end portion) facing each other in a first direction (front-rear direction), and an intermediate portion (front-rear intermediate portion) between the first end portion and the second end portion in the first direction. The cooling device (air conditioner unit 51) is provided at the first end portion (front end portion) of the vehicle body 2. Among the plurality of ducts 42, 43, 44, the ducts 42, 43 extending from the cooling device (air conditioner unit 51) to the device to be cooled have first extension portions 42a, 43a extending in the first direction (front-rear direction) in a range from the first end portion (front end portion) to the intermediate portion (front-rear intermediate portion), and have a second extension portion 42b extending in a direction different from the first direction (front-rear direction) at the intermediate portion (front-rear intermediate portion).

[0382] With the above configuration, the ducts 42, 43 branched to the left and right traveling structures 3L, 3R are arranged in a state where they converge at the first extension portions 42a, 43a, so that the piping is compact, looks good, and a wide arrangement space for the devices arranged around can be secured.

[0383] (Item A2) The work vehicle 1 according to Item A1, wherein the first extension portions 42a, 43a are arranged above the vehicle body 2 (vehicle body frame structure 20).

[0384] With the above configuration, the first extension portions 42a, 43a of the duct 42 can be piped together above the vehicle body 2, which is convenient for maintenance, and a wide arrangement space for other devices in the middle and lower parts of the vehicle body 2 can be secured.

[0385] (Item A3) The plurality of ducts 42, 43, 44 include a supply duct 42 extending to the device to be cooled (battery 37) for supplying the cooling air discharged from the cooling device (air conditioner unit 51) to the device to be cooled (battery 37), and a return duct 43, 44 extending from the device to be cooled (battery 37, 50) for returning the cooling air after cooling the device to be cooled (battery 37, 50) to the cooling device (air conditioner unit 51). At least the supply duct 42 of the supply duct 42 and the return ducts 43, 44 is a duct having the first extension portion 42a. The work vehicle 1 according to item A1 or A2.

[0386] With the above configuration, the first extension portion 42a of the supply duct 42 can be piped in a converged state, and a compact piping can be realized.

[0387] (Item A4) The return duct 43 has an extension portion 43b extending in a direction different from the first direction (front-rear direction), and the extension portion is arranged parallel to the second extension portion 42b extending in a direction different from the first direction (front-rear direction) of the supply duct 42. The work vehicle 1 according to item A3.

[0388] With the above configuration, the extension portions of the supply duct 42 and the return duct 43 in directions different from the first direction can be piped in a compact and visually clean state.

[0389] (Item A5) The supply duct 42 is connected to the lower part of the housing (side battery case 36) that houses the device to be cooled (side battery 37), and the return duct 43 is connected to the upper part of the housing (side battery case 36). The work vehicle 1 according to item A3 or A4.

[0390] With the above configuration, inside the housing (side battery case 36), the cooling air flowing in from the lower part of the housing connected to the supply duct 42 becomes hot enough to cool the device to be cooled (side battery 37) and rises, and can be efficiently discharged to the return duct 43 connected to the upper part of the housing.

[0391] (Item A6) The work vehicle 1 described in Item A5, wherein the device to be cooled is the battery (side battery) 37.

[0392] With the above configuration, the battery 37, which tends to become hot in the work vehicle 1, can be effectively cooled .

[0393] (Item A7) The return duct 43 is a duct having a first extension portion 43a that extends from the cooling device (air conditioner unit 51) to the device to be cooled (battery 50) and extends in the first direction (front-rear direction). The work vehicle 1 according to any one of Items A3 to A6, wherein the first extension portion 42a of the supply duct 42 and the first extension portion 43a of the return duct 43 are arranged in parallel.

[0394] With the above configuration, although the return duct 43 extends to the cooling device (air conditioner unit 51), the first extension portion 43a is arranged in parallel with the first extension portion 42a of the supply duct 42, so that a compact piping structure can be realized and it looks good.

[0395] (Item A8) A second device to be cooled (center battery 50) that is cooled by the cooling air from the cooling device (air conditioner unit 51) is provided on the vehicle body 2 separately from the device to be cooled (side battery 37). At least one duct 44 that extends from the cooling device (air conditioner unit 51) to the second device to be cooled (center battery 50) has a first extension portion 44a that extends in the first direction (front-rear direction) in a range from the first end portion (front end portion) to the middle portion (midpoint in the front-rear direction) of the vehicle body 2. The work vehicle 1 according to Item A7.

[0396] With the above configuration, the duct 44 connected to the second device to be cooled (battery 50) also has a first extension portion 44a, and a converged state can be ensured together with the other ducts 42 and 43.

[0397] (Item A9) The work vehicle 1 described in any of items A3 to A6, wherein a second cooling target device (battery 50) that is cooled by cooling air from the cooling device (air conditioning unit 51) is provided in the vehicle body 2, separate from the cooling target device (battery 37), and an exhaust passage 24d is formed in a housing (center battery case 24) that houses the second cooling target device (battery 50) for discharging the cooling air after cooling the second cooling target device (battery 50) to the cooling device (air conditioning unit 51), and the return duct 43 is connected to the housing (center battery case 24) and communicates with the exhaust passage 24d in the housing (center battery case 24).

[0398] With the above configuration, the return duct 43 for returning the cooling air after cooling the second cooling target device (battery 50) to the cooling device (air conditioning unit 51) can be shortened, and it is also possible to eliminate the first extension portion 43a, thereby ensuring ample space for arranging other devices, for example, on the upper part of the vehicle body 2.

[0399] (Item A10) The work vehicle according to item A9, wherein the second cooling target device is a battery (center battery) 50.

[0400] With the above-mentioned configuration, the battery 50, which tends to become hot inside the work vehicle 1, can be effectively cooled.

[0401] (Item A11) The vehicle includes a left running structure 3L provided on the left side of the vehicle body 2 and a right running structure 3R provided on the right side of the vehicle body 2, and the cooling target device (side battery 37) is A work vehicle 1 described in any of items A1 to A10, including a left cooled equipment (left side battery 37L) arranged on the row structure 3L and a right cooled equipment (right side battery 37R) arranged on the right traveling structure 3R.

[0402] With the above configuration, the structure of item A1 or the like can be applied to the duct structure for supplying the cooling air from the cooling device (air conditioner unit 51) to the equipment to be cooled (side battery 37) arranged on both the left and right sides of the vehicle body 2.

[0403] (Item A12) The plurality of ducts 42 and 43 include a left forward duct 42L extending to the left equipment to be cooled (left battery 37L) and a right forward duct 42R extending to the right equipment to be cooled (right battery 37R) for supplying the cooling air discharged from the cooling device (air conditioner unit 51) to the equipment to be cooled (battery 37), and a left return duct 43L extending from the left equipment to be cooled (left battery 37L) and a right return duct 43R extending from the right equipment to be cooled (right battery 37R) for returning the cooling air after cooling the equipment to be cooled (battery 37) to the cooling device (air conditioner unit 51). At least the left forward duct 42L and the right forward duct 42R extend from the cooling device (air conditioner unit 51) to each of the left equipment to be cooled (left battery 37L) and the right equipment to be cooled (right battery 37R), and are ducts having a first extension 42a extending in the first direction (front-rear direction) in the range from the first end (front end) to the middle part (midway part in the front-rear direction). The second extension 42b extending in a direction different from the first direction (front-rear direction) of the left forward duct 42L and the second extension 42b extending in a direction different from the first direction (front-rear direction) of the right forward duct 42R extend in directions opposite to each other with respect to the vehicle body 2. The left return duct 43L and the right return duct 43R each have an extension 43b extending in a direction different from the first direction (front-rear direction), and the extension 43b extending in a direction different from the first direction (front-rear direction) of the left return duct 43L and the extension 43b extending in a direction different from the first direction (front-rear direction) of the right return duct 43R extend in directions opposite to each other with respect to the vehicle body 2. The work vehicle 1 according to item A11.

[0404] With the above configuration, the forward duct 42 and the return duct 43 for circulating the cooling air between the left and right cooling target devices (battery 37) arranged on both left and right sides of the vehicle body 2 and the cooling device (air conditioner unit 51) can be piped compactly.

[0405] (Item A13) The first direction is the front-rear direction of the vehicle body 2, and the direction different from the first direction (front-rear direction) is the left-right direction of the vehicle body 2. The work vehicle 1 described in any one of Items A1 to A12.

[0406] With the above configuration, the first extension portions 42a and 43a of the plurality of ducts 42 and 43 can be arranged in a converged state by extending in the front-rear direction of the vehicle body 2. On the other hand, by having the extension portions 42b and 43b extending in the left-right direction, it is possible to pipe and connect to the cooling target device (battery 37) compactly.

[0407] (Item A14) The first end portion is the front end portion of the vehicle body 2. The work vehicle 1 described in Item A13.

[0408] With the above configuration, the cooling device (air conditioner unit) 51 is arranged at the front end portion of the vehicle body 2 where it is easy to take in outside air for generating cooling air, and the generation efficiency of the cooling air by the cooling device (air conditioner unit 51) can be improved.

[0409] (Item B1) A cooling device (air conditioner unit 51), a first equipment to be cooled (center battery 50) and a second equipment to be cooled (side battery 37) which are cooled by the cooling air discharged from the cooling device (air conditioner unit 51), a first cooling housing (center battery case 24) for housing the first equipment to be cooled (center battery 50), and a second cooling housing (side battery case 36) for housing the second equipment to be cooled (side battery 37). An intake port 24h is provided in the first cooling housing (center battery case 24) for taking in the air discharged from the second cooling housing (side battery case 36) after cooling the second equipment to be cooled (side battery 37). The work vehicle 1 is equipped with these components.

[0410] With the above configuration, the return duct 43 for sending the air after cooling the second equipment to be cooled (side battery 37) from the second cooling housing (side battery case 36) can be shortened, which contributes to the compactification of the piping structure such as ducts in the work vehicle 1 and the improvement of the freedom of the layout of the equipment.

[0411] (Item B2) In the first cooling housing (center battery case 24), a cooling air passage 24c for directing the cooling air from the cooling device (air conditioner unit 51) to the first equipment to be cooled (center battery 50) and an exhaust air passage 24d for discharging the air after cooling the first equipment to be cooled (center battery 50) to the cooling device (air conditioner unit 51) are formed. The air from the second cooling housing (side battery case 36) introduced into the first cooling housing (center battery case 24) through the intake port 24h merges with the air in the exhaust air passage 24d. The work vehicle 1 described in Item B1 is equipped with these components.

[0412] With the above configuration, the discharge routes of the air after cooling the first equipment to be cooled (center battery 50) and the air after cooling the second equipment to be cooled (side battery 37) are unified into one exhaust air passage 24d, which contributes to the reduction of the number of pipes for discharging the air.

[0413] (Item B3) In the first cooling housing (center battery case 24), a first air guiding device (fan 45) that guides air from the cooling air passage 24c to the exhaust air passage 24d and a second air guiding device (fan 46) that guides air from the intake port 24h to the exhaust air passage 24d are provided. The work vehicle 1 according to item B2.

[0414] With the above configuration, the air from the cooling air passage 24c and the air from the intake port 24h are reliably guided to the exhaust air passage 24d, contributing to an improvement in cooling efficiency and the like.

[0415] (Item B4) In the first cooling housing (center battery case 24), a partition plate 24e is provided above the first cooling target device (center battery case 24). The space below the partition plate 24e in the first cooling housing (center battery case 24) is the cooling air passage 24c, and the space above the partition plate 24e is the exhaust air passage 24d. The work vehicle 1 according to item B2 or B3.

[0416] With the above configuration, the partition plate 24e surely forms the exhaust air passage 24d above the cooling air passage 24c.

[0417] (Item B5) In the first cooling housing (center battery case 24), a vertical communication passage 24g that communicates the outlet of the cooling air passage 24c and the inlet of the exhaust air passage 24d is provided along the end of the partition plate 24e. At the outlet of the cooling air passage 24c, a first air guiding device (fan 45) that guides air from the cooling air passage 24c to the lower part of the communication passage 24g is provided. At the upper part of the communication passage 24g, a second air guiding device (fan 46) that guides the intake port 24h and the air introduced from the intake port 24h to the inlet of the exhaust air passage 24d is provided. The work vehicle 1 according to item B4. With the above configuration, by utilizing the tendency of the warmed air after cooling to rise, the cooled air can be smoothly guided to the exhaust air passage 24d formed above the cooling air passage 24c.

[0418] With the above configuration, by utilizing the tendency of the warmed air after cooling to rise, the cooled air can be smoothly guided to the exhaust air passage 24d formed above the cooling air passage 24c.

[0419] (Item B6) The first air guiding device and the second air guiding device are fans 45 and 46, and the work vehicle 1 described in any one of Items B3 to B5.

[0420] With the above configuration, due to the air suction effect and the air blowing effect of the fans 45 and 46, the air flow in the first cooling housing (center battery case 24) can be surely realized.

[0421] (Item B7) At least one of the first cooling target device and the second cooling target device is a battery 37 or 50, and the work vehicle 1 described in any one of Items B1 to B6.

[0422] With the above configuration, among the work vehicles 1, the batteries 37 and 50 that require temperature management to enable the electrical equipment and the like to operate well can be surely cooled.

[0423] (Item B8) The work vehicle 1 includes a vehicle body 2 and a traveling structure 3 provided on the side of the vehicle body 2, the cooling device (air conditioner unit 51) and the first cooling housing (center battery case 24) are arranged on the vehicle body 2, and the second cooling housing (side battery case 36) is arranged on the traveling structure 3, and is described in any one of Items B1 to B7.

[0424] With the above configuration, for the first cooling housing (center battery case 24) and the second cooling housing (side battery case 36) that are dispersedly arranged on the vehicle body 2 and the traveling structure 3, the effect of unifying the discharge routes as described above can also be achieved.

[0425] (Item C1) A work vehicle equipped with ducts 42, 43, and 44 that can expand and contract in response to changes in the vehicle shape.

[0426] With the above configuration, even in a work vehicle with a special structure in which the vehicle shape changes, when the shape changes, the ducts expand and contract, so that the connection between the devices by the ducts can be maintained.

[0427] (Item C2) The work vehicle 1 according to Item C1, comprising a first part and a second part that are linked to be relatively movable with respect to each other, wherein the ducts 42, 43, 44 extend across the first part and the second part, and have expansion and contraction parts 42c, 42d, 42e, 43c, 43d, 43e, 44c that can expand and contract according to the relative movement between the first part and the second part.

[0428] With the above configuration, by arranging the expansion and contraction parts 42c, 42d, 42e, 43c, 43d, 43e, 44c at locations where the effect of the expansion and contraction is high, the function of the piped ducts can be reliably maintained.

[0429] (Item C3) One of the first part and the second part is the vehicle body 2, and the other is the traveling structure 3 arranged on the left and right sides of the vehicle body 2. The work vehicle 1 according to Item C2. The work vehicle 1 according to Item C2, wherein the traveling structure 3 is arranged on the left and right sides of the vehicle body 2.

[0430] With the above configuration, the ducts 42, 43 that connect the devices arranged on the vehicle body 2 and the left and right traveling structures 3 respectively can be of a structure having expansion and contraction parts 42e, 43e that can expand and contract.

[0431] (Item C4) The vehicle body 2 is movable in the vertical direction with respect to the traveling structure 3, and the ducts 42, 43 have the expansion and contraction parts 42e, 43e in the vertical part arranged between the vehicle body 2 and the traveling structure 3. The work vehicle 1 according to Item C3.

[0432] With the above configuration, in response to the vehicle body 2 rising or the like and changing the vertical position with respect to the traveling structure 3, the expansion and contraction parts 42e, 43e expand and contract in the vertical direction, and the ducts 42, 43 can maintain the function as ducts that are passages for the cooling medium.

[0433] (Item C5) The work vehicle 1 according to item C4, comprising a cooling device (air conditioner unit 51) provided on the vehicle body 2 and a device to be cooled (battery 37) provided on the traveling structure 3 and cooled by a cooling medium supplied from the cooling device (air conditioner unit 51), wherein the ducts 42 and 43 extend between the cooling device (air conditioner unit 51) and the device to be cooled (battery 37) as passages for the cooling medium.

[0434] With the above configuration, even when the cooling device (air conditioner unit 51) and the device to be cooled (battery 37) are separately arranged on the vehicle body 2 and the traveling structure 3, they are surely connected by the ducts 42 and 43 having expandable and contractible portions 42c, 42d, 42e, 43c, 43d, and 43e.

[0435] (Item C6) One of the first part and the second part is the first part of the vehicle body 2, and the other is the second part of the vehicle body 2. The ducts 42 and 43 have the expandable and contractible portions 42c, 42d, 43c, and 43d at a portion disposed between the first part and the second part of the vehicle body 2. The work vehicle 1 according to any one of items C2 to C5.

[0436] With the above configuration, even when the first part and the second part move relative to each other and the vehicle body 2 is deformed, the expandable and contractible portions 42c, 42d, 43c, and 43d expand and contract, so that the ducts 42 and 43 can maintain their function as ducts for the cooling medium.

[0437] (Item C7) The first part (center battery case 24, air conditioner case 40, discharge manifold 41b) of the vehicle body 2 and the second part (vehicle body frame structure 20) are relatively movable in the front-rear direction, and the ducts 42, 43, 44 have the telescopic parts 42c, 43c, 44c in the front-rear direction part arranged between the first part (center battery case 24, air conditioner case 40, discharge manifold 41b) of the vehicle body 2 and the second part (vehicle body frame structure 20). The work vehicle 1 described in item C6.

[0438] With the above configuration, even when the first part (center battery case 24, air conditioner case 40, discharge manifold 41b) and the second part (vehicle body frame structure 20) of the vehicle body 2 move relative to each other in the front-rear direction, the telescopic parts 42c, 43c, 44c expand and contract in the front-rear direction, so that the ducts 42, 43, 44 can maintain their function as ducts for the passage of the cooling medium.

[0439] (Item C8) The first part (vehicle body center frame 21) and the second part (vehicle body side frame 22) of the vehicle body 2 are relatively movable in the left-right direction, and the ducts 42, 43 have the telescopic parts 42d, 43d in the left-right direction part arranged between the first part (vehicle body center frame 21) of the vehicle body 2 and the second part (vehicle body side frame 22). The work vehicle 1 described in item C6 or C7.

[0440] With the above configuration, even when the first part (vehicle body center frame 21) and the second part (vehicle body side frame 22) of the vehicle body 2 move relative to each other in the left-right direction, the telescopic parts 42d, 43d expand and contract in the left-right direction, so that the ducts 42, 43 can maintain their function as ducts for the passage of the cooling medium.

[0441] (Item C9) The work vehicle 1 according to any one of items C6 to C8, comprising a traveling structure 3 provided on the side of the vehicle body 2, the vehicle body 2 being relatively movable with respect to the traveling structure 3, and the ducts 42 and 43 being provided with a plurality of the telescopic portions 42c, 42d, 42e, 43c, 43d, and 43e in a portion disposed between the first portion and the second portion of the vehicle body 2 and in a portion disposed between the vehicle body 2 and the traveling structure 3.

[0442] With the above configuration, when the first part and the second part of the vehicle body 2 move relative to each other, and when the vehicle body 2 and the traveling structure 3 move relative to each other, the telescopic portions 42c, 42d, and 42e provided in the corresponding parts expand and contract respectively. Therefore, the duct 42 can maintain its function as a duct for the passage of the cooling medium.

[0443] (Item C10) The work vehicle 1 according to item C9, comprising a cooling device (air conditioner unit 51) provided in the first part or the second part of the vehicle body 2, and a device to be cooled (battery 37) provided in the traveling structure 3 and cooled by a cooling medium supplied from the cooling device (air conditioner unit 51), and the duct 42 extending between the cooling device (air conditioner unit 51) and the device to be cooled (battery 37) as a passage for the cooling medium.

[0444] With the above configuration, even when the cooling device (air conditioner unit 51) and the device to be cooled (battery 37) are separately arranged on the vehicle body 2 and the traveling structure 3, the two are surely connected by the duct 42 having the telescopic portions 42c, 42d, and 42e that can expand and contract.

[0445] (Item C11) The vehicle body 2 has a third part that is relatively movable with respect to the second part, and the ducts 42 and 43 have a plurality of the telescopic parts 42c, 42d, 43c, and 43d. The telescopic parts 42c, 42d, 43c, and 43d are provided in a part (a part where the telescopic parts 42c and 43c are provided) disposed between the first part (the center battery case 24, the air conditioner case 40, and the discharge manifold 41b) of the vehicle body 2 and the second part (the vehicle body center frame 21), and a part disposed between the second part (the vehicle body center frame 21) of the vehicle body 2 and the third part (the vehicle body side frame 22). The work vehicle 1 according to any one of Items C6 to C10.

[0446] With the above configuration, when the first part and the second part of the vehicle body 2 move relative to each other, and when the second part and the third part of the vehicle body 2 move relative to each other, the telescopic parts 42c, 42d, 43c, and 43d provided in the corresponding parts expand and contract respectively. Therefore, the ducts 42 and 43 can maintain their function as ducts for the passage of the cooling medium.

[0447] (Item C12) The first part (the center battery case 24, the air conditioner case 40, and the discharge manifold 41b) of the vehicle body 2 and the second part (the vehicle body frame structure 20) are relatively movable in the front-rear direction, and the second part (the vehicle body center frame 21) of the vehicle body 2 and the third part (the vehicle body side frame 22) are relatively movable in the left-right direction. The ducts 42 and 43 have a plurality of the telescopic parts 42c, 42d, 42e, 43c, 43d, and 43e. The telescopic parts 42c, 42d, 42e, 43c, 43d, and 43e are provided in a front-rear direction part disposed between the first part (the center battery case 24, the air conditioner case 40, and the discharge manifold 41b) of the vehicle body 2 and the second part (the vehicle body frame structure 20), and a left-right direction part disposed between the second part (the vehicle body center frame 21) of the vehicle body 2 and the third part (the vehicle body side frame 22). The work vehicle 1 according to Item C11.

[0448] With the above configuration, even when there is relative movement in the longitudinal direction between the first part and the second part of the vehicle body 2, and even when there is relative movement in the lateral direction between the second part and the third part of the vehicle body 2, the telescopic parts 42c, 42d, 43c, and 43d provided in the corresponding parts expand and contract respectively. Therefore, the ducts 42 and 43 can retain their function as ducts for the passage of the cooling medium.

[0449] (Item C13) A traveling structure 3 provided on the side of the vehicle body 2, a cooling device (air conditioner unit 51) provided in the first part (center battery case 24, air conditioner case 40, discharge manifold 41b) of the vehicle body 2, and a cooling target device (battery 37) disposed on the traveling structure 3 and cooled by a cooling medium supplied from the cooling device (air conditioner unit 51). The ducts 42 and 43 extend longitudinally as passages for the cooling medium from the cooling device (air conditioner unit 51) to the second part (vehicle body center frame 21) of the vehicle body 2, bend at the second part (vehicle body center frame 21) of the vehicle body 2, and extend laterally from the second part (vehicle body center frame 21) to the third part (vehicle body side frame 22), and extend vertically from the third part (vehicle body side frame 22) of the vehicle body 2 to the cooling target device (battery 37). The work vehicle 1 according to Item C12.

[0450] With the above configuration, the cooling device (air conditioner unit 51) on the vehicle body 2 and the cooling target device (battery 37) on the traveling structure 3 are connected, and the duct 42 is routed in a good route to achieve a compact and efficient piping structure in the work vehicle 1. By providing the aforementioned telescopic parts 42c, 42d, 42e, 43c, 43d, and 43e in such a duct 43, due to the expansion and contraction of the telescopic parts 42c, 42d, 42e, 43c, 43d, and 43e corresponding to the relative movement between the first part and the second part of the vehicle body 2, the relative movement between the second part and the third part, or the relative movement between the vehicle body 2 and the traveling structure 3, the duct 43 can retain its function as a duct for the passage of the cooling medium.

[0451] (Item D1) The work vehicle 1 includes a vehicle body 2, and left and right traveling structures 3L and 3R provided on the left and right sides of the vehicle body 2. In the vehicle body 2, a first device D1 (a working system electric unit E1, a hydraulic system electric unit E2) and a first adjusting device T1 (a radiator 52) for adjusting the temperature of the first device D1 (the working system electric unit E1, the hydraulic system electric unit E2) are arranged. In one of the left and right traveling structures 3L and 3R (the left traveling structure 3L), a second device D2L (a left front traveling system electric unit E3FL, a left rear traveling system electric unit E3RL) and a second adjusting device T2L (a radiator 71) for adjusting the temperature of the second device D2L are arranged. In the other of the left and right traveling structures 3L and 3R (the right traveling structure 3R), a third device D2R (a right front traveling system electric unit E3FR, a right rear traveling system electric unit E3RR) and a third adjusting device T2R (a radiator 71) for adjusting the temperature of the third device D2R are arranged.

[0452] With the above configuration, in the work vehicle 1 in a state where devices D1, D 2L, D2R (the working system electric unit E1, the hydraulic system electric unit E2, the left front traveling system electric unit E3FL, the left rear traveling system electric unit E3RL, the right front traveling system electric unit E3FR, the right rear traveling system electric unit E3RR) that are temperature adjustment targets are provided in both the vehicle body 2 and the left and right traveling structures 3, adjusting devices T1, T2L, T2R (radiators 52, 71) are provided in both the vehicle body 2 and each traveling structure 3, so the temperature adjustment effect of each device can be enhanced. Even if some trouble occurs in the temperature adjustment action for a certain device, the devices provided in other parts (the vehicle body 2 or the traveling structure 3) can be free from its influence. Also, even when the vehicle body 2 and the left and right traveling structures 3L and 3R are in a separated state, since the adjusting devices for temperature adjustment of each device are provided in each of the vehicle body 2 and the left and right traveling structures 3L and 3R, the connection points for piping etc. for sending the temperature adjustment medium for temperature adjustment of each device between the vehicle body 2 and the left and right traveling structures 3L and 3R can be reduced, improving maintainability etc.

[0453] (Item D2) The work vehicle 1 described in item D1, wherein at least one of the first adjustment device T1, the second adjustment device T2L, and the third adjustment device T2R is a radiator 52, 71.

[0454] With the above configuration, the water cooling effect by the radiators 52, 71 can be surely imparted to the corresponding devices D1, D2L, D2R (working system electric unit E1, hydraulic system electric unit E2, left front traveling system electric unit E3FL, left rear traveling system electric unit E3RL, right front traveling system electric unit E3FR, right rear traveling system electric unit E3RR).

[0455] (Item D3) The first adjustment device is a radiator 52, and the work vehicle 1 described in item D2, which is disposed at the front portion of the vehicle body 2.

[0456] With the above configuration, the radiator 52 is disposed at a position where it is easy to take in air for heat exchange, and the temperature adjustment effect can be enhanced.

[0457] (Item D4) The vehicle body 2 is provided with a first adjustment circuit C1 (R1) for circulating a temperature adjustment medium between the first adjustment device T1 (radiator 52) and the first device D1 (working system electric unit E1, hydraulic system electric unit E2). The one traveling structure 3 (left traveling structure 3L) is provided with a second adjustment circuit C2L (R2L) for circulating a temperature adjustment medium between the second adjustment device T2L (radiator 71) and the second device D2L (left front traveling system electric unit E2L). The other traveling structure 3 (right traveling structure 3R) is provided with a third adjustment circuit C2R (R2R) for circulating a temperature adjustment medium between the third adjustment device T2R (radiator 71) and the third device D2R (right front traveling system electric unit E2R). The work vehicle 1 according to any one of items D1 to D3.

[0458] With the above configuration, adjustment circuits C1, C2L, and C2R are formed to circulate a temperature adjustment medium between the adjustment devices T1, T2L, and T2R and the devices D1, D2L, and D2R, which are provided separately in the vehicle body 2 and the left and right traveling structures 3L and 3R, respectively. Even if there is a trouble in any one of the circuits, it is possible to avoid affecting other circuits, and it is easy to maintain the temperature adjustment effect of each device in the work vehicle 1. Further, when separating and connecting between the vehicle body 2 and the left and right traveling structures 3L and 3R, it is possible to save the labor of separating and connecting pipes between the adjustment circuits C1, C2L, and C2R, and the maintainability is excellent.

[0459] (Item D5) Among the first adjustment device T1, the second adjustment device T2L, and the third adjustment device T2R At least one includes radiators 52 and 71 and radiator fans 52a and 71a, and the first adjustment circuit R1 (C1), the second adjustment circuit R2L (C2L), or the third adjustment circuit R2R (R2R) connected to the radiators 52 and 71 includes a cooling water storage tank 59 and 73 and a cooling water discharge pump 58 and 72. The work vehicle 1 described in Item D4.

[0460] With the above configuration, a water-cooled cooling (temperature adjustment) circuit R1, R2L, R2R (C1, C2L, C2R) including a radiator or the like is formed in at least one of the vehicle body 2 and the left and right traveling structures 2L and 3R.

[0461] (Item D6) The work vehicle 1 according to any one of Items D1 to D5, wherein at least one of the first adjustment device T1, the second adjustment device T2L, and the third adjustment device T2R is an air temperature adjustment device (air conditioner unit 51).

[0462] With the above configuration, an air-cooled cooling (temperature adjustment) action by an air temperature adjustment device (air conditioner unit 51) can be exerted on at least one of the vehicle body 2 and the left and right traveling structures 2L and 3R.

[0463] (Item D7) The work vehicle 1 according to any one of items D1 to D6, wherein at least one of the first adjustment device T1, the second adjustment device T2L, and the third adjustment device T2R is a heater.

[0464] With the above configuration, it is possible to exert a temperature adjustment effect on the equipment provided in at least one of the vehicle body 2 and the left and right traveling structures 2L and 3R, for example, by supplying warm water heated by a heater.

[0465] (Item D8) The left and right traveling structures 3 each have wheels 5, and the second adjustment device T2L (radiator 71) and the third adjustment device T2R (radiator 71) are respectively arranged so as to face the ground contact surface of the wheels 5 of the traveling structure 3. The work vehicle 1 according to any one of items D1 to D6.

[0466] With the above configuration, the adjustment device (radiator 71) can be arranged on the traveling structure 3 with a limited left - right width so as not to protrude as much as possible from the range within the left - right width of the ground contact surface of the wheels 5.

[0467] (Item D9) The second adjustment device T2L and the third adjustment device T2R are radiators 71, and each is inclined with respect to the front - rear direction in front of the wheel 5. The work vehicle 1 according to item D8.

[0468] With the above configuration, when the radiator 71 is arranged in a posture facing directly in the front - rear direction, it has a considerably large width in the left - right direction. By inclining it with respect to the front - rear direction, it is provided on the traveling structure 3 so as to be within the left - right width of the ground contact surface of the wheel 5 as described above in the left - right direction.

[0469] (Item D10) The first device D1 is an electrical device (working system electric unit E1) for driving and controlling a working device connected to the vehicle body 2 and / or a hydraulic device (hydraulic pump 57) for controlling a hydraulic actuator (width - changing cylinder 8, vehicle - body lifting cylinder 9) equipped on the vehicle body 2. The work vehicle 1 according to any one of items D1 to D9.

[0470] With the above configuration, among the components of the vehicle body 2, temperature adjustment (cooling) is particularly required for electrical equipment and hydraulic equipment. The temperature adjustment action by the first adjustment device T1 (such as the air conditioner unit 51 and the radiator 52) can be exerted on these devices.

[0471] (Item D11) The second device D2L and the third device D2R are each a traveling motor 7 that drives the wheel 5 of the traveling structure 3 in the work vehicle 1 described in Items D1 to D10.

[0472] With the above configuration, the temperature adjustment action by the second adjustment device T2L and the third adjustment device T2R (such as the radiator 71) can be exerted on the traveling motor 7, which is the main drive device in the traveling structure 3.

[0473] (Item E1) A work vehicle 1 comprising a vehicle body 2, a left traveling structure 3L provided on the left side of the vehicle body 2, a right traveling structure 3R provided on the right side of the vehicle body 2, a temperature adjustment device T3 (radiator 52) arranged in any one of the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R, temperature adjustment target devices including a first device D1 arranged in the vehicle body 2, a second device D2L arranged in the left traveling structure 3L, and a third device D2R arranged in the right traveling structure 3R, which are devices temperature-adjusted by the temperature adjustment device T3 (radiator 52), and a temperature adjustment circuit C3 that sends a temperature adjustment medium from the temperature adjustment device T3 (radiator 52) to the temperature adjustment target devices. The temperature adjustment circuit C3 branches from the temperature adjustment device T3 (radiator 52) and is respectively connected to the first device D1, the second device D2L, and the third device D2R.

[0474] With the above configuration, a temperature adjustment medium from one temperature adjustment device T3 (radiator 52) can be supplied to a plurality of temperature adjustment target devices provided in the vehicle body 2 and the left and right traveling structures 3L, 3R via the branched temperature adjustment circuit C3. By sharing the temperature adjustment device T3, the effect of reducing the number of parts and cost can be obtained.

[0475] (Item E2) The temperature adjustment circuit C3 includes a first temperature adjustment circuit (branch circulation circuit) C3a that circulates a temperature adjustment medium between the temperature adjustment device T3 (radiators 52, 71) and the first device D1, a second temperature adjustment circuit (branch circulation circuit) C3b that circulates a temperature adjustment medium between the temperature adjustment device T3 (radiators 52, 71) and the second device D2L, and a third temperature adjustment circuit (branch circulation circuit) C3c that circulates a temperature adjustment medium between the temperature adjustment device T3 (radiators 52, 71) and the third device D2R. The work vehicle according to item E1, which is provided with these components.

[0476] With the above configuration, among the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R, for example, in each traveling structure 3, a temperature adjustment medium is circulated among a plurality of devices so as to surround the front traveling system electric unit E3F (front traveling motor 7F) and the rear traveling system electric unit E3R (rear traveling motor 7R), and a circulation circuit of the temperature adjustment medium that returns to a common temperature adjustment device T3 (radiators 52, 71) is configured.

[0477] (Item E3) The work vehicle 1 according to item E1 or E2, wherein the temperature adjustment device T3 is radiators 52, 71.

[0478] With the above configuration, the water cooling action by the radiators 52, 71 can be surely applied to the devices D1, D2L, D2R provided in the vehicle body 2 and the left and right traveling structures 3L, 3R.

[0479] (Item E4) The work vehicle 1 according to item E3, wherein at least one of the first device D1, the second device D2L, and the third device D2R is a battery 50, 37 cooled by cooling water from the radiators 52, 71.

[0480] With the above configuration, among the work vehicle 1, the batteries 50, 37 that require temperature management in order to enable good operation of electrical equipment and the like can be surely cooled.

[0481] (Item E5) Among the first device D1, the second device D2L, and the third device D2R, at least one is an electrical equipment (working system electric unit E1, hydraulic system electric unit E2, traveling system electric units E3FL, E3FR, E3RL, E3RR) cooled by the cooling water from the radiators 52 and 71, and the work vehicle 1 according to Item E3 or E4.

[0482] With the above configuration, the temperature adjustment action by the second adjustment device T2L and the third adjustment device T2R (radiator 71, etc.) can be exerted on the traveling motor 7, which is an electrical equipment that particularly requires temperature adjustment (cooling) among the traveling structures 3.

[0483] (Item E6) The temperature adjustment device T3 is an air temperature adjustment device (air conditioner unit 51), and the work vehicle 1 according to any one of Items E1 to E5.

[0484] With the above configuration, an air-cooling type cooling (temperature adjustment) action by the air temperature adjustment device (air conditioner unit 51) can be exerted on the temperature adjustment target devices D1, D2L, and D2R provided on the vehicle body 2 and the left and right traveling structures 2L and 3R.

[0485] (Item E7) Among the first device D1, the second device D2, and the third device D3, at least one is a battery 50 cooled by the cooling air from the air temperature adjustment device (air conditioner unit 51), and the work vehicle 1 according to Item E6.

[0486] With the above configuration, an air-cooling type cooling (temperature adjustment) action by the air temperature adjustment device (air conditioner unit 51) can be exerted on the temperature adjustment target devices D1, D2L, or D2R provided on any one of the vehicle body 2 and the left and right traveling structures 2L and 3R.

[0487] (Item E8) The temperature adjustment device T3 is a heater, and the work vehicle 1 according to Item E1 or E2.

[0488] With the above configuration, it is possible to supply a temperature-adjusting refrigerant such as warm water whose temperature is adjusted by a heater to the temperature-adjusting target devices D1, D2L, and D2R provided in the vehicle body 2 and the left and right traveling structures 2L and 3R.

[0489] As described above, the embodiments of the present invention have been described. However, the embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The scope of the present invention is shown not by the above description but by the claims, and it is intended that all modifications within the meaning and scope equivalent to the claims are included.

Explanation of Reference Numerals

[0490] 1 Work vehicle 2 Vehicle body 3 Traveling structure 3L Left traveling structure 3R Right traveling structure 21 Vehicle body center frame 22 Vehicle body side frame 22L Left vehicle body side frame 22R Right vehicle body side frame 36 Side battery case 37 Side battery 42 Forward duct 42c Expansion / contraction part 42d Expansion / contraction part 42e Expansion / contraction part 43 Return duct 43c Expansion / contraction part 43d Expansion / contraction part 43e Expansion / contraction part 51 Air conditioner unit

Claims

1. A work vehicle equipped with a duct that can expand and contract in response to changes in the vehicle shape.

2. Comprising a first part and a second part that are linked to be relatively movable with respect to each other, The duct according to claim 1, wherein the duct extends across the first part and the second part, and has an expansion and contraction part that can expand and contract in response to relative movement between the first part and the second part.

3. The work vehicle according to claim 2, wherein one of the first part and the second part is the vehicle body, and the other is a traveling structure disposed on the left and right sides of the vehicle body.

4. The vehicle body is movable in the vertical direction with respect to the traveling structure, The work vehicle according to claim 3, wherein the duct has the expansion and contraction part in a vertical part disposed between the vehicle body and the traveling structure.

5. A cooling device provided on the vehicle body, A cooling target device provided on the traveling structure and cooled by a cooling medium supplied from the cooling device, Comprising, The work vehicle according to claim 4, wherein the duct extends between the cooling device and the cooling target device as a passage for the cooling medium.

6. One of the first part and the second part is a first part of the vehicle body, and the other is a second part of the vehicle body, The work vehicle according to claim 2, wherein the duct has the expansion and contraction part in a part disposed between the first part and the second part of the vehicle body.

7. The first part and the second part of the vehicle body are relatively movable in the front-rear direction, The work vehicle according to claim 6, wherein the duct has the expansion and contraction part in a front-rear part disposed between the first part and the second part of the vehicle body.

8. The first part and the second part of the vehicle body are relatively movable in the left-right direction, The work vehicle according to claim 6, wherein the duct has the expansion and contraction part in a left-right part disposed between the first part and the second part of the vehicle body.

9. Comprising a traveling structure provided on the side of the vehicle body, The vehicle body is relatively movable with respect to the traveling structure, The work vehicle according to claim 6, wherein the duct is provided with a plurality of the expansion and contraction parts in a part disposed between the first part and the second part of the vehicle body and in a part disposed between the vehicle body and the traveling structure.

10. A cooling device provided on the first part or the second part of the vehicle body, A cooling target device provided on the traveling structure and cooled by a cooling medium supplied from the cooling device, comprising: The work vehicle according to claim 9, wherein the duct extends between the cooling device and the cooling target device as a passage for the cooling medium.

11. The vehicle body has a third portion that is relatively movable with respect to the second portion, The work vehicle according to claim 6, wherein the duct is provided with the plurality of telescopic portions at a portion disposed between the first portion and the second portion of the vehicle body and at a portion disposed between the second portion and the third portion of the vehicle body.

12. The first portion and the second portion of the vehicle body are relatively movable in the front-rear direction, The second portion and the third portion of the vehicle body are relatively movable in the left-right direction, The work vehicle according to claim 11, wherein the duct is provided with the plurality of telescopic portions at a front-rear direction portion disposed between the first portion and the second portion of the vehicle body and at a left-right direction portion disposed between the second portion and the third portion of the vehicle body.

13. A traveling structure provided on the side of the vehicle body, A cooling device provided on the first portion of the vehicle body, A cooling target device disposed on the traveling structure and cooled by a cooling medium supplied from the cooling device, comprising: The work vehicle according to claim 12, wherein the duct extends in the front-rear direction from the cooling device to the second portion of the vehicle body as a passage for the cooling medium, bends at the second portion of the vehicle body, extends in the left-right direction from the second portion to the third portion, and extends in the vertical direction from the third portion of the vehicle body to the cooling target device.

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