Work vehicle

Abstract

This invention achieves a compact duct piping structure by improving a structure for taking in cooling air from a cooling device into a housing for housing a cooling target device.　A work vehicle 1 comprises: a cooling device (51); a first cooling target device (50) and a second cooling target device (37) that are cooled by cooling air discharged from the cooling device (51); a first cooling housing (24) that houses the first cooling target device (50); and a second cooling housing (36) that houses the second cooling target device (37). The first cooling housing (24) is provided with an intake (24h) for taking in air discharged from the second cooling housing (36) after cooling the second cooling target device (37).

Description

Work vehicles

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

[0002] In recent years, agricultural work using work vehicles has been shifting from a manual operation performed by a worker in the vehicle to a remote-controlled operation where the worker remotely controls the vehicle using a terminal device, or an autonomous operation where the vehicle is driven by GPS along a route set in the field, in which the work vehicle is driven unmanned.

[0003] Therefore, it is conceivable that the form of the vehicle will change from a conventional tractor type with a driver's seat to a form that is more convenient for carrying out the intended work, such as agricultural work. For example, it is conceivable to use an unmanned work vehicle consisting of a body and left and right running structures with wheels etc. arranged on both the left and right sides of the body, and to perform agricultural work by placing the body across a ridge and arranging the left and right running structures on both the left and right sides of the ridge.

[0004] Furthermore, in a work vehicle of this type, it is conceivable to arrange a battery in the vehicle body as a driving power source for the work equipment etc. connected to the vehicle body, and to arrange another battery in the running structure as a driving power source for the electric motor for driving the wheels.

[0005] For example, as disclosed in Patent Document 1, a technique is known in which a battery pack mounted on a work vehicle or the like is cooled by an air-cooling system.

[0006] Japanese Patent Publication "Patent No. 6091844"

[0007] In the above-mentioned unmanned work vehicle, when batteries are mounted separately on the vehicle body and the traveling structure, and when considering a configuration in which air from an air conditioning unit is sent as cooling air to the cases that house each battery, the duct structure is important in configuring such an air-cooling system.

[0008] In order to realize this duct structure, various issues must be resolved, such as how to efficiently send cooling air to battery cases that are distributed throughout the vehicle body and running structures as described above, as well as creating a compact piping structure that takes into account the space available for arranging other equipment.The duct structure disclosed in Patent Document 1 has a simple configuration that circulates cooling air between the battery case and the air conditioner, and does not take into account the placement of the battery pack inside the work vehicle.

[0009] Furthermore, in order to achieve compact duct piping and shortened ducts, it is possible to devise a cooling air passage structure in the case that houses the battery, but the battery case structure shown in Patent Document 1 does not represent a technical solution in this regard.

[0010] A work vehicle according to one embodiment of the present invention comprises a cooling device, a first cooling target device and a second cooling target device that are 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, and the first cooling housing is provided with an intake port for taking in air discharged from the second cooling housing after cooling the second cooling target device.

[0011] The first cooling housing may be formed with a cooling air passage for blowing cooling air from the cooling device onto the first cooling target device, and an exhaust air passage for discharging the air after cooling the first cooling target device to the cooling device. The air from the second cooling housing introduced into the first cooling housing through the intake port may be merged with the air in the exhaust air passage.

[0012] A first air guide device that guides air from the cooling air passage to the exhaust air passage, and a second air guide device that guides air from the intake port to the exhaust air passage may be provided within the first cooling housing.

[0013] A partition plate may be provided above the first cooling target device within the first cooling housing, and the space below the partition plate within the first cooling housing may be the cooling air passage, and the space above the partition plate may be the exhaust air passage.

[0014] A vertical communication passage may be provided within the first cooling housing along an end of the partition plate, connecting the outlet of the cooling air passage with the inlet of the exhaust air passage. A first air guide device may be provided at the outlet of the cooling air passage to guide air from the cooling air passage to a lower part of the communication passage. The intake port and a second air guide device may be provided above the communication passage to guide the air introduced from the intake port to the inlet of the exhaust air passage.

[0015] The first air guiding device and the second air guiding device may be fans.

[0016] At least one of the first target device and the second target device may be a battery.

[0017] The work vehicle may include a vehicle body and a running structure provided on the side of the vehicle body, and the cooling device and the first cooling housing may be arranged on the vehicle body, and the second cooling housing may be arranged on the running structure.

[0018] According to the present invention, by providing an intake port in the first cooling housing for taking in air from the second cooling housing, the duct from the second cooling housing can be shortened to the intake port of the first cooling housing without extending to the cooling device, and the air after cooling the first cooling target device and the air after cooling the second cooling target device can be merged and discharged in the first cooling housing.By shortening the duct, etc., it is possible to ensure a large amount of free space for arranging other equipment.

[0019] 1 is a perspective view of a work vehicle according to a first embodiment. FIG. 2 is a plan view of a work vehicle according to the first embodiment. FIG. 3 is a left side view of a work vehicle according to the first embodiment. FIG. 4 is a right side view of a work vehicle according to the first embodiment. FIG. 5 is a front view of a work vehicle according to the first embodiment. FIG. 6 is a rear view of a work vehicle according to the first embodiment. FIG. 7 is a left side cross-sectional view of a work vehicle according to the first embodiment. FIG. 8 is a perspective view of a work vehicle according to the first embodiment with the vehicle body raised. FIG. 9 is a plan view of a work vehicle according to the first embodiment with the vehicle body extended to the right. FIG. 10 is a schematic side view showing the internal structure of a center battery case employed in the work vehicle according to the first embodiment. FIG. 11 is a schematic developed view of a side battery case employed in the work vehicle according to the first embodiment. FIG. 12 is a block diagram showing a water-cooling circuit structure within the vehicle body employed in the work vehicle according to the first embodiment. FIG. 13 is a block diagram showing a water-cooling circuit structure in a traveling structure employed in the work vehicle according to the first embodiment. FIG. 14 is a block diagram showing a control system structure of a work vehicle. FIG. 15 is a schematic side view showing the internal structure of a center battery case employed in a work vehicle according to a second embodiment. FIG. 16 is a plan view of a work vehicle according to the second embodiment. FIG. 17 is a schematic side view showing a first modified example of a center battery case employed in a work vehicle according to the second embodiment. Fig. 1 is a schematic side view showing a second modified example of a center battery case employed in a work vehicle according to a second embodiment. Fig. 2 is a schematic side view showing the internal structure of a center battery case employed in a work vehicle according to a third embodiment. Fig. 3 is a plan view of a work vehicle according to a third embodiment. Fig. 4 is a schematic plan view showing a first temperature adjustment circuit structure in a work vehicle. Fig. 5 is a schematic plan view showing a second temperature adjustment circuit structure in a work vehicle. Fig. 6 is a schematic plan view showing a third temperature adjustment circuit structure in a work vehicle.

[0020] A preferred embodiment of a work vehicle 1 according to the present invention will now be described. Figures 1 to 14 are diagrams showing one embodiment (first embodiment) of a work vehicle 1. Figure 1 is a perspective view of the work vehicle 1. Figure 2 is a plan view of the work vehicle 1. Figure 3 is a left side view of the work vehicle 1. Figure 4 is a right side view of the work vehicle 1. Figure 5 is a front view of the work vehicle 1. Figure 6 is a rear view of the work vehicle 1. Figure 7 is a side cross-sectional view of the work vehicle 1.

[0021] Fig. 8 is a perspective view of the work vehicle 1 with the body 2 raised. Fig. 9 is a plan view of the work vehicle 1 with the right portion of the 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 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.

[0022] In the following description, the direction indicated by the arrow X1 in FIG. 1 is referred to as the forward direction, the direction indicated by the arrow X2 is referred to as the backward direction, the direction indicated by the arrow Y1 is referred to as the left direction, the direction indicated by the arrow Y2 is referred to as the right direction, the direction indicated by the arrow Z1 is referred to as the upward direction, and the direction indicated by the arrow Z2 is referred to as the downward direction.

[0023] Examples of work performed by the work vehicle 1 include, but are not limited to, agricultural work, industrial (civil engineering, construction, etc.) work, and transportation work. In a preferred embodiment of the present invention, the work performed by the work vehicle 1 is agricultural work (farm work). Below, an example will be described in which the work performed by the work vehicle 1 is farm work. In this case, the work vehicle 1 is an agricultural work vehicle.

[0024] The basic structure of a work vehicle 1 will be described with reference to Figures 1 to 7, 14, etc. The work vehicle 1 comprises 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.

[0025] The vehicle body 2 is provided with a PTO shaft 65 (see Figure 14) at its rear end or the like for transmitting driving force to a work implement connected to the work vehicle 1, and can also be fitted with a coupling device 60 (see Figure 14) for connecting the work implement to the work vehicle 1.

[0026] The structure of the connecting device 60 can be variously considered depending on the type of work device (implement), but a typical structure is a three-point link mechanism having a pair of left and right lower links and one top link.

[0027] The working device can be coupled to a portion (for example, the front end) of the body 2 of the work vehicle 1 other than the rear end, and can receive driving force from the work vehicle 1. Alternatively, the work vehicle 1 can be provided with the working device mounted on the body 2, for example, without being provided with a coupling device.

[0028] The configuration of the vehicle body 2 arranged between the left traveling structure 3L and the right traveling structure 3R and the various devices provided on the vehicle body 2 will be described.

[0029] The vehicle body 2 has a vehicle body frame structure 20 , a center battery case (front body case) 24 and a PTO case (rear body case) 26 supported by the vehicle body frame structure 20 .

[0030] The body frame structure 20 has a body center frame 21, a left body side frame 22L disposed on the left side of the body center frame 21, and a right body side frame 22R disposed on the right side of the body center frame 21. Hereinafter, each of the left body side frame 22L and the right body side frame 22R may be referred to as a body side frame 22.

[0031] A flat support member 23 (see FIG. 2, etc.) is fixed to the lower portion of the vehicle body center frame 21 from the front end to the midpoint in the front-rear direction, and a rectangular parallelepiped center battery case 24 hangs down from the support member 23. The upper end of the center battery case 24 is engaged with the support member 23 so as to be movable in the front-rear direction.

[0032] A situation detection device 10 and a positioning device 11 are provided on the upper part of the support member 23 or the vehicle body central frame 21 to detect the situation around the work vehicle 1 (presence or absence of obstacles, the growth rate of crops growing in the ridges, the width of the ridges, etc.).

[0033] In this embodiment shown in Figures 1 to 6, the extension portions 43a of the ducts 43L and 43R are suspended on the vehicle body central frame 21 as described below, and as shown in Figure 1, etc., a stay 10d that spans these is provided on the vehicle body central frame 21, and the situation detection device 10 and the positioning device 11 are provided on the stay 10d.

[0034] The situation detection device 10 and the positioning device 11 may be mounted on the vehicle body 2 (vehicle body central frame 21) without interfering with ducts or the like, and the mounting structure to the vehicle body 2 is not limited.

[0035] For example, in another embodiment (second embodiment) shown in Figure 16 and described below, there is no extension portion 43a of the ducts 43L, 43R on the vehicle body central frame 21, so the situation detection device 10 is attached directly to the support member 23 provided directly below the upper part of the vehicle body central frame 21 without using the stay 10d.

[0036] Each vehicle body side frame 22 is connected to the vehicle body center frame 21 so as to be movable relative to the vehicle body center frame 21 in the left-right direction. A pair of width-changing cylinders 8A, 8B extending in the left-right direction is provided on the upper part of the vehicle body center frame 21 as a vehicle body deformation device (actuator) 80 (see FIG. 14 ) for changing the left-right width of the vehicle body 2, i.e., for deforming the vehicle body 2. Hereinafter, each of the pair of width-changing cylinders 8A, 8B may be referred to as a width-changing cylinder 8.

[0037] The width-adjusting cylinder 8A extends and retracts 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-adjusting cylinder 8A is attached to the upper part of the vehicle body center frame 21, and the piston rod extends leftward from the cylinder body, with the tip of the piston rod attached to the upper part of the left vehicle body side frame 22L.

[0038] The width-adjusting cylinder 8B extends and retracts to change the distance between the vehicle center frame 21 and the right vehicle side frame 22R. The cylinder body of the width-adjusting cylinder 8B is attached to the upper part of the vehicle center frame 21 in front of or behind (in this embodiment, in front of) the cylinder body of the width-adjusting cylinder 8A, and the piston rod extends rightward from the cylinder body, with the tip of the piston rod attached to the upper part of the right vehicle side frame 22R.

[0039] In this way, the extension and contraction of each width changing cylinder 8 causes the vehicle side frames 22 to move forward and backward relative to the vehicle center frame 21, changing the left-right width of the vehicle body 2 as described above, and deforming the vehicle body 2.

[0040] For example, as shown in Figure 9, by extending the piston rod of the width-changing cylinder 8B, the right vehicle body side frame 22R moves away from the vehicle body center frame 21 to the right, and the vehicle body 2 is deformed so that the right part of the vehicle body 2 expands.

[0041] As a result, the right running structure 3R connected to the right vehicle side frame 22R also moves to the right together with the right vehicle side frame 22R, and the vehicle width, which is the distance between the left running structure 3L and the right running structure 3R in the left-right direction and the distance between the corresponding left and right wheels 5, increases.

[0042] 9, when the piston rod of the width changing cylinder 8A is extended, the left body side frame 22L and the left running structure 3L move leftward away from the body center frame 21, and the body 2 is deformed so that the left portion of the body 2 expands. This also makes it possible to change the vehicle width.

[0043] For deformation of the vehicle body 2 in the direction of increasing the vehicle width, both the width changing cylinders 8A, 8B may be extended or retracted to move both the left and right vehicle body side frames 22L, 22R. Also, the extension and retraction of the width changing cylinders 8A, 8B may be synchronized.

[0044] The width-changing cylinder 8, which serves as a body deformation device for changing the left-right width of the body 2, may be a cylinder of any structure, such as a hydraulic cylinder, an air cylinder, or an electric cylinder, as long as it functions as the body deformation device 80.

[0045] Furthermore, the body deformation device 80 does not have to have a structure with a cylinder such as the width change cylinder 8, as long as it has the function of changing the left and right width of the body 2, and may have a structure such that the body side frame 22 moves forward and backward relative to the body center frame 21 by rotating a screw rod with a motor, for example.

[0046] As for the vehicle body 2 as a whole, the left vehicle body side frame 22L of the vehicle body frame structure 20 is connected to the left running frame 30L of the left running structure 3L, and the right vehicle body side frame 22R is connected to the right running frame 30R of the right running structure 3R via multiple mast structures 31 (see Figure 1, etc.) arranged between the vehicle body 2 (each vehicle body side frame 22) and each running structure 3 (each running frame 30), so that they can move up and down relative to the left and right running structures 3.

[0047] As shown in Figures 2, 6, etc., the work vehicle 1 is equipped with a pair of left and right body lifting cylinders 9, i.e., a left body lifting cylinder 9L and a right body lifting cylinder 9R, as actuators (hydraulic actuators) for raising and lowering the body 2, i.e., as body movement devices 90 (see Figure 14) for moving the body 2 relative to the left and right running structures 3.

[0048] The cylinder bottoms, which are the upper ends of each body lift cylinder 9 (left body lift cylinder 9L, right body lift cylinder 9R), are connected to the upper parts of the body side frames 22 (left body side frames 22L, right body side frames 22R). Meanwhile, the piston rod heads, which are the lower ends of each body lift cylinder 9, are supported by brackets or the like that protrude inward from the vehicle-inner ends of the traveling frames 30 (left traveling frames 30L, right traveling frames 30R).

[0049] Under normal circumstances, the piston rods of the left body lift cylinder 9L and the right body lift cylinder 9R are retracted, and the body 2 is located at the lowest position in its vertical movement range, as shown in Figures 1, 3 to 6, etc. The left body lift cylinder 9L and the right body lift cylinder 9R simultaneously extend their piston rods with the same stroke, causing the entire body 2 to rise, as shown in Figure 8. More specifically, as the piston rods of the left body lift cylinder 9L and the right body lift cylinder 9R extend, the body 2 moves upward relative to the left and right traveling structures 3 while being guided by the mast structure 31.

[0050] It is also conceivable that the left and right tilt of the vehicle body 2 can be adjusted by differentially extending and retracting the left body lifting cylinder 9L and the right body lifting cylinder 9R. For example, if the ground tilts downward and left and the left running structure 3L becomes lower than the right running structure 3R, causing the vehicle body 2 to tilt downward and left, it is conceivable that by extending only the left body lifting cylinder 9L, the left part of the vehicle body 2 can be moved upward relative to the left running structure 3L, thereby keeping the vehicle body 2 horizontal in the left and right directions.

[0051] The body lifting cylinders 9 do not have to be a pair on the left and right, and there are no restrictions on the number or location within the body 2. The actuator that moves the body 2 up and down does not have to be an extendable actuator like the body lifting cylinders 9, and may be configured to move the body 2 up and down by the rotation of an electric motor, for example.

[0052] In this embodiment, as described above, the width-changing cylinder 8, which is the body deformation device 80, and the body lifting cylinder 9, which is the body movement device 90, are hydraulic actuators, and as shown in Figure 14, the control device 15 controls the respective control valves in the control valve unit 27, thereby controlling the extension and contraction movements.

[0053] In addition, the width change cylinder 8 and the vehicle body lifting cylinder 9 described in Figure 14 refer to the width change cylinders 8A and 8B and the vehicle body lifting cylinders 9L and 9R, respectively, and the control device 15 can individually control the extension and contraction movements of these.

[0054] 2, 5, 7, etc., a battery (center battery) 50 is housed in the center battery case 24. In consideration of the weight balance of this heavy center battery 50 within the entire work vehicle 1, or for other reasons (for example, in relation to the layout of equipment within the vehicle body 2), the center battery case 24 is movable in the fore-and-aft direction relative to the vehicle body center frame 21 (vehicle body frame structure 20). In other words, the vehicle body 2 is also deformed when the center battery case 24 moves fore-and-aft relative to the vehicle body center frame 21.

[0055] Note that a battery movement actuator 81, such as a hydraulic cylinder, may be provided as a vehicle body deformation device 80 (see FIG. 14 ) to move the center battery case 24 forward or backward relative to the vehicle body center frame 21. Alternatively, without providing such a vehicle body deformation device, an operator may directly push or pull the center battery case 24 with their hands to move it forward or backward relative to the vehicle body center frame 21.

[0056] An air conditioning unit (air temperature adjustment device) 51 is provided in front of the center battery case 24, and a radiator 52 is provided immediately in front of the air conditioning unit 51. The radiator 52 is located at the front end of the vehicle body 2, and nothing is provided in front of the radiator 52 on the vehicle body 2. The front side of the radiator 52 is not blocked by other components, so the radiator 52 can efficiently take in outside air and achieve good heat exchange efficiency. A radiator fan 52a is provided behind the radiator 52. In other words, an air-cooling device and a water-cooling device are provided immediately in front of the center battery case 24.

[0057] The air conditioning unit 51 and the radiator fan 52a can be operated using 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 results of a temperature detection device 18 provided in the work vehicle 1, for example.

[0058] 10, the center battery case 24 is connected to the air conditioning unit 51 without a duct, and the cooling air discharged from the air conditioning 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 returned to the air conditioning unit 51. The structure of this center battery case 24 will be described in detail later in relation to the duct piping between the air conditioning unit 51 and the side battery cases 36 described below.

[0059] As shown in Figure 7 and other figures, the PTO case 26 is supported by the vehicle body center frame 21 behind the center battery case 24. A PTO shaft 65 (see Figure 14) for transmitting power to a working device connected to the PTO case 26 and the like is journaled on the PTO case 26 and protrudes rearward from the rear end of the PTO case 26, which serves as the rear end of the vehicle body 2, for example.

[0060] 12 are provided as electrical equipment inside or outside the PTO case 26. The work electric unit E1 and the hydraulic electric unit E2 are an electrical equipment unit for controlling the drive of the PTO shaft 65, and have an electric motor 54 as a work prime mover and an inverter 53 for controlling the output of the electric motor 54.

[0061] The hydraulic system electric unit E2 is an electrical equipment unit for controlling the drive of a hydraulic pump 57 for supplying hydraulic oil to hydraulic actuators provided on the work vehicle 1, including the width change cylinder 8 and vehicle body lifting cylinder 9 provided on the vehicle body 2, the lift cylinder 61 and attitude adjustment cylinder 63 (see Figure 14) provided on the coupling device 60, and the steering cylinder 35 provided on the traveling structure 3, and has an electric motor 56 as a hydraulic system prime mover and an inverter 55 (see Figure 12) for controlling the output of the electric motor 56.

[0062] As shown in FIGS. 6 and 7, an electric motor 56 and an inverter 55 as the hydraulic electric unit E2 are disposed below the PTO case 26, and a hydraulic pump 57 is connected to the electric motor 56.

[0063] The electric motor 54 of the work system electric unit E1 is driven by power obtained from the center battery 50 and / or the side battery 37, and the output drives the PTO shaft 65. The inverter 53 converts the direct current from the center battery 50 into alternating current, and applies the alternating current to the electric motor 54 at a set voltage and / or frequency.

[0064] As shown in FIG. 14, the voltage and / or frequency setting value of the inverter 53 is controlled by the control device 15, thereby controlling the output rotation speed and / or torque of the electric motor 54, and thereby controlling the rotation speed and / or torque of the PTO shaft 65.

[0065] A transmission mechanism for transmitting the output of the electric motor 54 to the PTO shaft 65 may be provided within the PTO case 26. This transmission mechanism may have a gear, an endless belt, or another structure. This transmission mechanism may also be a stepped or continuously variable transmission. Furthermore, this transmission mechanism may be provided with a clutch, a braking device, or the like.

[0066] The electric motor 56 of the hydraulic electric unit E2 is driven by power obtained from the center battery 50 and / or the side battery 37, and the output drives the hydraulic pump 57. The inverter 55 converts the direct current from the center battery 50 into alternating current, and applies the alternating current to the electric motor 56 at a set voltage and / or frequency.

[0067] As shown in FIG. 14 , the set value of the voltage and / or frequency of the inverter 55 is controlled by the control device 15, whereby the output rotation speed and / or torque of the electric motor 56 is controlled, and thereby the rotation speed and / or torque of the hydraulic pump 57 is controlled.

[0068] Assuming that the coupling device 60 is a three-point link mechanism, the left and right lower links of the coupling device 60 are connected to the left and right lift arms, and the left and right lower links move up and down in response to the up and down movement of the left and right lift arms due to the extension and contraction of the left and right lift cylinders 61. As a result, the working device attached to the left and right lower links and the top link of the coupling device 60 moves up and down (raise and lower).

[0069] Furthermore, 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 extending and retracting the attitude adjustment cylinder 63, the tilt angle in the left-right direction of the working implement attached to the connecting device 60 can be adjusted.

[0070] With this configuration, even if the working implement during agricultural work begins to tilt left or right due to the slope of the field, the working implement can be kept horizontal in the left-right direction by adjusting the distance between the lift arm and the lower link by extending and retracting the posture adjustment cylinder 63, and good ridges that do not slope left or right can be formed in the work marks of the working implement, which is, for example, a ridge-forming device.

[0071] As described above, a working device can be connected to the coupling device 60 attached to the PTO case 26 or the like. Furthermore, the working device connected to the vehicle body 2 via the coupling device 60 can receive driving force from the PTO shaft 65 (see FIG. 14 ) protruding from the PTO case 26.

[0072] Examples of the work device include, but are not limited to, a device for performing agricultural work (farm work), a device for performing civil engineering work, a device for performing construction work, a device for performing transportation work, etc. In the embodiment shown below, the work device is a device for performing agricultural work.

[0073] Examples of working equipment for agricultural work include a spraying device for spreading fertilizer, chemicals, and other such materials, a sowing device for sowing seeds, a tilling device for tilling the soil, a tilling device (plow) for tilling the soil, a weeding device for weeding, a soil-piling device for piling up soil, etc. However, the type of working equipment is not particularly limited as long as it is an equipment for performing agricultural work.

[0074] Furthermore, if the working device is an electric working device, instead of being driven by power extracted from the PTO shaft 65, it may be driven by power extracted from the center battery 50 and / or the side battery 37 via a power line to the outside of the vehicle body 2.

[0075] The working implement may be connected to the work vehicle 1 while being disposed to the side or front of the vehicle body. Furthermore, when the working implement is disposed in front of the work vehicle 1, for example, the coupling device 60 may be attached to the center battery case 24, for example, and the working implement disposed in front of the work vehicle 1 may be coupled to the work vehicle 1 via the coupling device 60 thus attached to the front of the vehicle body 2.

[0076] Furthermore, in addition to or instead of the PTO shaft 65 provided at the rear of the vehicle body 2, a front PTO shaft may be provided facing forward from the center battery case 24, and the front PTO shaft may drive a working implement at the front of the work vehicle 1. Note that an example of such a front-mounted agricultural working implement is a combine unit that combines the reaping section, threshing section, sorting section, etc. of a combine harvester.

[0077] Furthermore, the coupling device 60 may be detachable from the PTO case 26, etc. Furthermore, it is also conceivable that a mounting portion to which the coupling device 60 can be attached may be provided in a location on the vehicle body 2 other than the PTO case 26, such as the center battery case 24, so that the working equipment can be connected to the work vehicle 1 at the front of the vehicle body 2.

[0078] Furthermore, the working device may be mounted on, for example, the upper part of the body frame structure 20 of the body 2 of the work vehicle 1 without using the coupling device 60. In this case, the PTO shaft that transmits driving force to the working device may be provided so as to protrude upward from the upper part of the body frame structure 20 (for example, the body central frame 21).

[0079] As described above, the work vehicle 1 is equipped with hydraulic actuators such as the width change cylinder 8 and the vehicle body lifting cylinder 9 provided on the vehicle body 2, and further the steering cylinder 35 provided on the traveling structure 3. Furthermore, the coupling device 60 attached to the vehicle body 2 may be equipped with hydraulic actuators such as the lift cylinder 61 and attitude adjustment cylinder 63 described above.

[0080] To control the operation of these hydraulic actuators, one or more control valve units 27 are attached to the outside of the PTO case 26. Each control valve unit 27 incorporates a control valve that controls the flow of hydraulic oil between the hydraulic pump 57 and the hydraulic actuator that is the subject of hydraulic control, and is also provided with ports for fluidly connecting the control valve to the hydraulic pump 57, the hydraulic actuator, etc. via oil pipes, etc.

[0081] Note that control valves that hydraulically control different hydraulic actuators may be combined to form one control valve unit 27. Furthermore, the control valve may be provided inside the PTO case 26, rather than just outside the PTO case 26 as described above.

[0082] Furthermore, when the control valve of the control valve unit 27 is an electromagnetic valve, the control valve unit 27 may be electrically connected to the control device 15 or the like by an electric wire or the like.

[0083] In addition, instead of the battery 50, an internal combustion engine (engine) may be placed inside the center battery case 24, etc., and the engine output may be used to drive the hydraulic pump 57 for operating the hydraulic actuator described above, and the engine output may be transmitted to the PTO shaft 65 to drive the PTO shaft 65.

[0084] As described above, the vehicle body 2 can be "deformed" by the center battery case 24 moving in the longitudinal direction relative to the vehicle body center frame 21 and by the left and right vehicle body side frames 22 moving in the lateral direction relative to the vehicle body center frame 21. The width changing cylinder 8 functions as a vehicle body deformation device (actuator) that deforms the vehicle body 2.

[0085] The vehicle body 2 is also capable of "moving" up and down relative to the left and right traveling structures 3L, 3R. The vehicle body lifting cylinder 9 functions as a vehicle body moving device (actuator) that moves the vehicle body 2.

[0086] As described above, the shape of the work vehicle 1 made up of the vehicle body 2 and the left and right traveling structures 3L, 3R changes as the vehicle body 2 itself deforms and the entire vehicle body 2 moves up and down relative to the left and right traveling structures 3L, 3R. This shape of the work vehicle 1 will be referred to as the "vehicle shape."

[0087] 14 , a vehicle body deformation device 80 including the width changing cylinder 8, the battery moving actuator 81, etc., and a vehicle body movement device 90 including the vehicle body lifting / lowering cylinder 9, etc., are collectively referred to as a vehicle shape changing device 100. A control device 15 controls each device included in the vehicle shape changing device 100.

[0088] As described above, in addition to the width change cylinder 8, battery movement actuator 81, and vehicle body lifting cylinder 9 included in the vehicle shape change device 100, the lift cylinder 61, attitude adjustment cylinder 63, etc. included in the coupling device 60 are all hydraulic actuators, and operate using hydraulic oil discharged from the hydraulic pump 57 driven by the electric motor 56 of the hydraulic system electric unit E2.

[0089] As described above, in the front portion of the vehicle body 2, an air conditioning unit 51 included in the air-cooling device 110 (see FIG. 14) and a radiator 52 (with radiator fan 52a) included in the water-cooling device 120 (see FIG. 14) are disposed immediately in front of the center battery case 24. Of these, the circulation circuit (duct) structure of the cooling air from the air conditioning unit 51 will be described in detail later, and here, the circulation circuit structure 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, 12, and 13.

[0090] A radiator 52 is arranged at the front of the vehicle body 2 so as to extend in the left-right and up-down directions, and the wind generated by the rotation of a radiator fan 52a arranged immediately behind the radiator 52 is blown onto the radiator 52, thereby promoting heat exchange (cooling) in the radiator 52.

[0091] A pair of electric cooling water pumps 58A, 58B and a reservoir tank 59 (see FIGS. 5, 7, etc.) are provided in the space behind the radiator 52 and below the air conditioning unit 51 within the vehicle body 2.

[0092] The electric cooling water pump 58A supplies cooling water drawn from a reservoir tank 59 to the inverter 53 and electric motor 54 of the working electric unit E1 to cool them, and the electric cooling water pump 58B supplies cooling water drawn from the reservoir tank 59 to the inverter 55 and electric motor 56 of the hydraulic electric unit E2 to cool them.

[0093] It should be noted that either of the pair of electric cooling water pumps 58 shown in FIG. 5 etc. may be the electric cooling water pump 58A for the working electric unit E1, and either may be the electric cooling water pump 58B for the hydraulic electric unit E2.

[0094] The radiator 52 is a cooling device (air-cooling device) that cools the cooling water discharged from the electric cooling water pumps 58A, 58B and circulated within the running structure 3. The radiator fan 52a is driven by electric power obtained from the center battery 50 and / or the side battery 37, and promotes heat exchange of the cooling water in the radiator 52.

[0095] In this way, as shown in FIG. 12, a water-cooled cooling (temperature adjustment) circuit R1 is configured in the vehicle body 2, with cooling water passages provided for circulating cooling water among the radiator 52 (radiator fan 52a), electric cooling water pumps 58A, 58B, working electric unit E1, hydraulic electric unit E2, etc.

[0096] That is, the water-cooled cooling (temperature adjustment) circuit R1 includes a circuit for supplying cooling water to the working electric unit E1 (electric motor 54, etc.) and a circuit for supplying cooling water to the hydraulic electric unit E2 (electric motor 56, etc.) as parallel circuits, and electric cooling water pumps 58A, 58B are provided as pumps that individually discharge cooling water to each cooling water supply circuit, so that cooling water can be efficiently supplied to each of the equipment to be cooled (i.e., each of the working electric unit E1 and the hydraulic electric unit E2), and the flow of each cooling water can be individually controlled.

[0097] 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 consists of a front wheel unit 4F supported at the front of the traveling frame 30 and a rear wheel unit 4R supported at the rear of the traveling frame 30.

[0098] Each wheel unit 4 has one wheel 5 and a wheel drive case 32 that supports an 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.

[0099] The front wheels 5F and the rear wheels 5R have approximately the same diameter. Alternatively, the front wheels 5F and the rear wheels 5R may have different diameters. Furthermore, at least one of the front wheels 5F and the rear wheels 5R may be used as a drive wheel (drive sprocket) of the crawler-type traveling device.

[0100] Furthermore, the running frame 30 of the left running structure 3L is the left running frame 30L, the front wheel unit 4F supported at the front of the left running frame 30L is the left front wheel unit 4FL having the left front wheel 5FL, and the rear wheel unit 4R supported at the rear of the left running frame 30L is the left rear wheel unit 4RL that supports the left rear wheel 5RL.

[0101] On the other hand, the running frame 30 of the right running structure 3R is the right running frame 30R, the front wheel unit 4F supported at the front of the right running frame 30R is the right front wheel unit 4FR that supports the right front wheel 5FR, and the rear wheel unit 4R supported at the rear of the right running frame 30R is the right rear wheel unit 4RR that supports the right rear wheel 5RR.

[0102] The upper part of the wheel drive case 32 of each wheel unit 4 houses the travel motor 7, a gear mechanism that transmits the output of the travel motor 7, and the like, and a rotating cylinder part 32a shown in Figures 5, 6, etc. extends vertically downward from the upper part. The rotating cylinder part 32a is connected to the upper part of the wheel drive case 32 so as to be rotatable relative to the upper part.

[0103] A vertical transmission shaft having an axis extending in the up-down (vertical) direction is supported within the rotating cylinder 32a so as to be rotatable about the axis. The central axes (axles) 5a of the wheels 5 are inserted into and supported at the lower end of the rotating cylinder 32a. In other words, the axles 5a protrude outward on the left and right from the bottom of the rotating cylinder 32a of the wheel drive case 32, and the wheels 5 provided around the axles 5a are disposed on the left and right outer sides of the rotating cylinder 32a.

[0104] A transmission mechanism having a bevel gear, an endless belt, etc., which links the output shaft of the travel motor 7 with the upper part of the transmission shaft on the vertical axis of the rotating cylinder 32a, is housed in the upper part of the wheel drive case 32. Furthermore, a transmission mechanism having a bevel gear, etc., which links the lower part of the vertical transmission shaft in the rotating cylinder 32a with the axle 5a of the wheels 5, is housed in the lower part of the rotating cylinder 32a.

[0105] In addition, since the running frame 30 supports the wheel drive case 32 that supports the axle 5a of the wheel 5, it will be described hereinafter as the running frame 30 supporting the axle 5a.

[0106] With the above-described configuration, the output of the travel motor 7 is transmitted to the wheels 5 via a transmission mechanism such as a bevel gear mechanism within the wheel drive case 32, thereby driving the wheels 5. That is, the left front wheel 5FL, the right front wheel 5FR, the left rear wheel 5RL, and the right rear wheel 5RR are each a drive wheel driven by the output of its own travel motor 7.

[0107] Hereinafter, the traveling motor 7 of the front wheel unit 4F in each traveling structure 3 may be referred to as a front traveling motor 7F, and the traveling motor 7 of the rear wheel unit 4R may be referred to as a rear traveling motor 7R.

[0108] In addition, the driving motor 7 of the left front wheel unit 4FL in the left running structure 3L may be referred to as the left front driving motor 7FL, the driving motor 7 of the left rear wheel unit 4RL may be referred to as the left rear driving motor 7RL, and the driving motor 7 of the right front wheel unit 4FR in the right running structure 3R may be referred to as the right front driving motor 7FR, and the driving motor 7 of the right rear wheel unit 4RR may be referred to as the right rear driving motor 7RR.

[0109] The upper part of the wheel drive case 32, which houses the travel motor 33 etc., is attached and fixed to the travel frame 30, while the rotating cylinder part 32a is freely rotatable around an axis in the vertical direction relative to the upper part.

[0110] A steering gear mechanism 34 is mounted on the exterior of the wheel drive case 32 to rotate the rotating cylinder portion 32a relative 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.

[0111] 14 and other figures, when the steering cylinder 35 extends and retracts in response to a command from the control device 15, the arm rotates, which activates the steering gear mechanism 34, causing the rotating cylinder portion 32a of each wheel drive case 32 to rotate about its vertical axis while supporting the wheel 5. In other words, the wheel 5 is not only a drive wheel driven by the traveling motor 7 as described above, but also a steering wheel that can rotate left and right relative to the traveling frame 30, i.e., whose angle in the left and right direction can be changed.

[0112] Each of the travel motors 7 is an electric motor, and the travel motors 7 of the front wheel unit 4F and the rear wheel unit 4R are driven by power obtained from the side battery 37 and / or the center battery 50. The travel structure 3 is also provided with an inverter 6 for controlling the output of the travel motor 7. As shown in Figure 14, the inverter 6 is controlled by a control device 15, which controls the output rotation speed and output rotation direction of the corresponding travel motor 7.

[0113] Note that the block diagram in Figure 14 only shows the combination of the traction motor 7 and inverter 6 for one wheel unit 4, 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, thereby individually controlling the rotation speed and direction of each wheel 5.

[0114] The traveling frame 30 of each traveling structure 3 supports a side battery 37, a front inverter 6F for the front traveling motor 7F of the front wheel unit 4F, and a rear inverter 6R for the rear traveling motor 7R of the rear wheel unit 4R.

[0115] 1 etc., the side battery 37 is housed in a side battery case 36 supported by the traveling frame 30 between the front wheels 5F and the rear wheels 5R. The traveling frame 30 supports a front inverter 6F for the front traveling motor 7F just in front of the side battery case 36, and a rear inverter 6R for the rear traveling motor 7R just behind the side battery case 36.

[0116] Hereinafter, the side battery 37 supported by the left running frame 30L of the left running structure 3L will be referred to as the left side battery 37L, the front inverter 6F supported by the left running frame 30L will be referred to as the left front inverter 6FL, and the rear inverter 6R supported by the left running frame 30L will be referred to as the left rear inverter 6RL.

[0117] In addition, the side battery 37 supported by the right running frame 30R of the right running structure 3R will be referred to as the right side battery 37R, the front inverter 6F supported by the right running frame 30R will be referred to as the right front inverter 6FR, and the rear inverter 6R supported by the right running frame 30R will be referred to as the right rear inverter 6RR.

[0118] In addition, 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 the front traveling system electric unit E3F (see Figure 13), while 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 the rear traveling system electric unit E3R (see Figure 13).

[0119] Furthermore, the combination of the left front inverter 6FL and the left front traveling motor 7FL in the left traveling structure 3L will be referred to as the left front traveling system electric unit E3FL, the combination of the left rear inverter 6RL and the left rear traveling motor 7RL will be referred to as the left rear traveling system electric unit E3RL, and the combination of the right front inverter 6FR and the right front traveling motor 7FR in the right traveling structure 3R will be referred to as the right front traveling system electric unit E3FR, and the combination of the right rear inverter 6RR and the right rear traveling motor 7RR will be referred to as the right rear traveling system electric unit E3RR (see Figure 21).

[0120] As with the traction motor 7 and inverter 6 described above, the block diagram of Figure 14 shows only one steering cylinder 35, but this steering cylinder 35 means one provided for each wheel unit 4, and the control device 15 controls the control valve for the steering cylinder 35 for each individual wheel unit 4, thereby individually controlling the steering angle (left and right turning angle) of each wheel 5.

[0121] Each steering cylinder 35 may be configured as an air cylinder, a water cylinder, or the like other than a hydraulic cylinder. Furthermore, the actuator that steers the wheels 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, in addition to such a telescopic actuator.

[0122] A radiator 71, a radiator fan 71a, a pair of electric cooling water pumps 72A and 72B, and a reservoir tank (a tank for storing cooling water) 73 are provided at the front of each traveling frame 30.

[0123] As shown in FIG. 13, the electric cooling water pump 72A supplies cooling water drawn in from a reservoir tank 73 to the front travel motor 7F and front inverter 6F (front traveling system electric unit E3F) of the front wheel unit 4F to cool them, and the electric cooling water pump 72B supplies cooling water drawn in from the reservoir tank 73 to the rear travel motor 7R and rear inverter 6R (rear traveling system electric unit E3R) of the rear wheel unit 4R to cool them.

[0124] In addition, either of the pair of electric cooling water pumps 72 provided at the front of each traveling frame 30 shown in Figure 1 etc. may be the electric cooling water pump 72A for the front traveling system electric unit E3F, and either may be the electric cooling water pump 72B for the rear traveling system electric unit E3R.

[0125] The radiator 71 is a cooling device (air-cooling device) that cools the cooling water discharged from the electric cooling water pumps 72A, 72B and circulated within the running structure 3. The radiator fan 71a is driven by electric power obtained from the side battery 37 and / or the center battery 50, and promotes heat exchange of the cooling water in the radiator 71.

[0126] 2 and other figures, the front end of the running frame 30 is inclined rearward from the left-right inner side to the left-right outer side in a plan view, and the radiator 71 is arranged to extend in the vertical direction along the front end of the running frame 30, and is also arranged inclined parallel to the inclined front end of the running frame 30 in a plan view, as shown in Fig. 2 and other figures. In other words, the radiator 71 is arranged inclined so that the front end is closer to the left-right inner side and the rear end is closer to the left-right outer side.

[0127] In this way, nothing is placed in front of the radiator 71, which is located at the front end of the running frame 30 (running structure 3). Therefore, the front surface of the radiator 71 is not blocked by other members, allowing the radiator 71 to efficiently take in outside air and improve heat exchange efficiency.

[0128] The radiator 71 is disposed in a tilted manner as described above in plan view, above and in front of the front wheels 5F, so as to face the upper front part of the contact (tread) surface of the front wheels 5F. In this way, the radiator 71 is disposed in the front part of the running frame 30 so as to fit within the limited left-right width of the running frame 30 without protruding from the left and right ends of the running frame 30 (the end on the vehicle body 2 side and the end opposite the vehicle body 2).

[0129] Furthermore, as shown in Figures 2, 5, 6, etc., the left and right outer end faces of the running frame 30 are approximately flush with the left and right outer end faces of the wheels 5 (front wheels 5F and rear wheels 5R) supported by the running frame 30, so the radiator 71 does not protrude from the left and right outer ends of the wheels 5.

[0130] As shown in Figure 9, in each traveling structure 3, a water-cooled cooling (temperature adjustment) circuit R2 is configured, which is provided with cooling water passages for circulating cooling water between the radiator 71, electric cooling water pumps 72A, 72B, front traveling system electric unit E3F, rear traveling system electric unit E3R, etc.

[0131] That is, the water-cooled cooling (temperature adjustment) circuit R2 is equipped with a cooling water supply circuit to the front traveling system electric unit E3F (front traveling motor 7F, etc.) and a cooling water supply circuit to the rear traveling system electric unit E3R (rear traveling motor 7R, etc.) as parallel circuits, and a pair of electric cooling water pumps 72 are provided as pumps that discharge cooling water individually to these parallel cooling water supply circuits, so that cooling water can be efficiently supplied to each of the equipment to be cooled (i.e., each of the front traveling system electric unit E3F (front traveling motor 7F, etc.) and the rear traveling system electric unit E3R (rear traveling motor 7R, etc.)), and the flow of each cooling water can be individually controlled.

[0132] The water-cooled cooling (temperature control) circuit R2 provided in the left running structure 3L may be referred to as the left water-cooled cooling (temperature control) circuit R2L, and the water-cooled cooling (temperature control) circuit R2 provided in the right running structure 3R may be referred to as the right water-cooled cooling (temperature control) circuit R2R.

[0133] Next, a first embodiment of the air-cooling system for the work vehicle 1 will be described with reference to Figures 1 to 11. As described above, the work vehicle 1 is provided with an air conditioning unit 51 at the front of the vehicle body 2.

[0134] The air conditioning unit 51 has a compressor, a heat exchanger, an outlet, an air intake 51a, etc., and cools the air compressed by the compressor in the heat exchanger, discharges the air from the outlet as cooled air, and collects the air after cooling each device to be cooled at the air intake 51a.

[0135] The work vehicle 1 is equipped with a center battery 50 provided in the vehicle body 2 and side batteries 37 provided on the left and right running structures 3, which are devices to be cooled by cooling air discharged from an air conditioning unit 51, which is an air-cooled cooling device.

[0136] That is, the cooling air from the air conditioning unit 51 provided in the vehicle body 2 is distributed and supplied to the equipment to be cooled that is located in three locations: the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R.

[0137] The duct structure in the air-cooling system according to the first embodiment shown in Figures 1 to 11 constitutes a cooling air circulation circuit that supplies and recovers cooling air from the air conditioning unit 51 to each device to be cooled.

[0138] First, in this embodiment, the center battery case 24 that houses the center battery 50 has a cooling air inlet 24a at the bottom of the front end and a cooling air outlet 24b at the top of the front end, as shown in Figure 10. An outlet manifold 41a is interposed between an outlet provided at the rear of the air conditioning unit 51 and the cooling air inlet 24a at the front end of the center battery case 24.

[0139] The center battery case 24 has a horizontal partition plate 24e extending in the front-to-rear direction inside, and the space below the partition plate 24e is a cooling air passage 24c for directing cooling air toward the center battery 50, which is the equipment to be cooled, and the space above the partition plate 24e is an exhaust air passage 24d for sending the air, after cooling the center battery 50, to the cooling air outlet 24b.

[0140] The partition plate 24e is positioned higher than approximately half the height of the center battery case 24 in the vertical direction, and the vertical width of the cooling air passage 24c is greater than the vertical width of the exhaust air passage 24d. In other words, a relatively large volume of space can be secured within the center battery case 24 for directing cooling air toward the center battery 50.

[0141] The partition plate 24e also provides thermal insulation between the exhaust air passage 24d and the cooling passage 24c. Specifically, the partition plate 24e is made of a heat insulating material or is provided with a heat insulating material, so that the temperature of the heated air passing through the exhaust air passage 24d is not transferred to the cooling air passage 24c.

[0142] Within the center battery case 24, a vertically extending partition plate 24f is connected to the rear end of the partition plate 24e, and the partition plates 24e, 24f are arranged in an inverted L-shape when viewed from the left side. The space behind the partition plate 24f is a communication passage 24g. Thus, the rear portions of the cooling air passage 24c and the exhaust air passage 24d are in communication with each other via the vertically extending communication passage 24g.

[0143] The cooling air, which has been temperature-adjusted by the air conditioning 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 through the cooling air inlet 24a is directed toward the center battery 50 as it flows rearward in the cooling air passage 24c, and cools the center battery 50.

[0144] In the cooling air passage 24c, the cooling air that has cooled the center battery 50 is instead heated by the center battery 50 and becomes hotter than when it was introduced into the cooling air passage 24c from the cooling air inlet 24a. The cooling air thus heated moves upward in the connecting passage 24g and flows into the exhaust passage 24d above the cooling air passage 24c.

[0145] Furthermore, the cooling air that has cooled the center battery 50 flows forward in the exhaust passage 24d and is discharged to the front of the center battery case 24 through the cooling air outlet 24b at the front end of the center battery case 24.

[0146] As shown in Figures 3 and 10, an air conditioning case 40 that houses an air conditioning unit 51 is provided immediately in front of the center battery case 24, and the air intake 51a of the air conditioning unit 51 opens toward the space of the air conditioning room 40a inside the air conditioning case 40.

[0147] The cooling air discharged from the cooling air outlet 24b to the outside of the center battery case 24 is drawn (returned) into the air conditioning unit 51 via the space within the air conditioning compartment 40a and the air intake port 51a.

[0148] The air conditioning unit 51 may be provided with an intake manifold (see intake manifold 51b in FIG. 19) communicating with the air intake port 51a, and a duct may be provided from the cooling air outlet 24b to the intake manifold.

[0149] A fan 45 is disposed within the center battery case 24 below the vertical partition plate 24f at a location where the rear end of the cooling air passage 24c communicates with the lower portion of the communication passage 24g.

[0150] The fan 45 is configured to suck air from the front cooling air passage 24c and discharge it to the rear communication passage 24g.

[0151] That is, the fan 45 sucks in the air that flows 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 connecting passage 24g, thereby generating rearward-directed cooling air within the cooling air passage 24c.

[0152] Furthermore, the fan 45 exhausts air rearward, thereby generating an upward airflow in the communication passage 24g and a forward airflow in the exhaust passage 24d.

[0153] In this way, the fan 45 smooths the flow of cooling air from the cooling air inlet 24a to the cooling air outlet 24b within the center battery case 24.

[0154] Next, a configuration for circulating cooling air between the air conditioning unit 51 and the side battery cases 36L, 36R of the left and right running structures 3L, 3R will be described.

[0155] The work vehicle 1 includes a vehicle body 2, a cooling device provided in the vehicle body 2, at least one device to be cooled by 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 and a second end that face each other in a first direction, and a middle portion between the first end and the second end in the first direction, the air conditioning unit 51 is provided at the first end of the vehicle body 2, and among the plurality of ducts, the duct extending from the air conditioning unit 51 to the device to be cooled has a first extension portion that extends in the first direction in a range from the first end to the middle portion, and has a second extension portion that extends in a direction different from the first direction at the middle portion.

[0156] In this embodiment, the cooling device is an air conditioning unit 51 that is an air temperature adjustment device (air conditioner), but it may be a fan or a heat pump that uses engine heat as long as it blows out cooling air to cool the equipment to be cooled.

[0157] In addition, in this embodiment, the equipment to be cooled is a battery (a center battery 50 provided in the vehicle body 2 and a side battery 37 provided in each running structure 3), but any equipment that can be cooled by cooling air can be used, and hydraulic equipment such as hydraulic pumps and electrical equipment such as electric motors can also be used as the equipment to be cooled.

[0158] Furthermore, it is sufficient that at least one cooling target device is cooled by a plurality of ducts. In this embodiment, for example, the plurality of ducts corresponds to the outward duct 42 and the return duct 43 described below that are used to cool the side battery 37 provided on one of the left and right running structures 3. In addition, the plurality of ducts also corresponds to the pair of left and right outward ducts 42L and 42R described below that are used to cool the left and right side batteries 37L and 37R.

[0159] The vehicle body 2 has a first end and a second end that face each other in a first direction, and a middle portion between the first end and the second end in the first direction, and the cooling device is provided at the first end of the vehicle body 2. In this embodiment, the first direction is the front-rear direction, and the first end is the front end, and the second end is the rear end, but this is not limited thereto, and the first end may be the rear end and the second end may be the front end, or the first direction may be, for example, the left-right direction, and the first end and the second end may be the left end and the right end. Furthermore, the first direction may be an oblique direction.

[0160] Furthermore, among the multiple ducts mentioned above, the duct extending from the cooling device (air conditioning unit 51) to the equipment to be cooled has a first extension portion extending in the first direction in the range from the first end to the midpoint, and has a second extension portion extending in a direction different from the first direction in the midpoint of the vehicle body 2.

[0161] In this embodiment, the intermediate portion of the vehicle body 2, which is the second extension portion (extension portion 42b described below in this embodiment) extending in a direction different from the first direction, is located in a position corresponding to the side battery case 36, which is located in a position approximately midway between the front and rear of the running structure 3 in the longitudinal direction, but is not limited to this. For example, if the side battery case 36 is located near the rear end of the running structure 3, the intermediate portion of the vehicle body 2 where the second extension portion is provided may be defined as being near the rear end of the vehicle body 2. Alternatively, the side battery case 36 may remain located approximately midway between the front and rear of the running structure 3, and the intermediate portion of the vehicle body 2 where the second extension portion is provided may be located rearward of the side battery case 36 and near the rear end of the vehicle body 2.

[0162] In addition, in this 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, but this portion is not limited to extending in such a direction and may also extend in the up-down direction.Furthermore, if the first direction is a direction other than the front-to-back direction, this direction may also be defined as the front-to-back direction.

[0163] Below, we will explain the structure of an air-cooling system in which the equipment to be cooled by the cooling air discharged from an air conditioning unit 51 as a cooling device is the center battery 50 provided on the vehicle body 2 and the side batteries 37 provided on the left and right running structures 3L, 3R. We will mainly explain the air-cooling system related to the first embodiment shown in Figures 1 to 11, etc., but also explain the structure common to the second embodiment shown in Figures 15 to 18 and the third embodiment shown in Figures 19 to 20.

[0164] First, we will explain the cooling air circulation structure between the air conditioning unit 51 and the side battery 37. As shown in Figure 10 and other figures, an outlet manifold 41b that protrudes above the vehicle body 2 (vehicle body center frame 21) is provided on the upper part of the air conditioning unit 51 as an outlet for cooling air from the air conditioning unit 51 to the side battery case 36.

[0165] In order to supply the cooling air discharged from the air conditioning unit 51 to the side battery 37, an outward duct 42 extends from the air conditioning unit 51 to the side battery 37. In other words, of the multiple ducts that circulate the cooling air between the cooling device (air conditioning unit 51) and the equipment to be cooled (side battery 37), the outward duct 42 corresponds to the duct that extends from the cooling device (air conditioning unit 51) to the equipment to be cooled (side battery 37).

[0166] Specifically, the outward duct 42 extends from the discharge manifold 41b located at the front end of the vehicle body 2 to the cooling air inlet 36a (see Figure 11) of the side battery case 36, which is a housing that houses the side battery 37, and is piped so that it passes through the upper part of the vehicle body 2 (the upper part of the vehicle body side frame 22) in the range from the front end (an example of the first end) of the vehicle body 2 to the midway between the front and rear.

[0167] On the vehicle body side frames 22 (upper part of the vehicle body 2), the outbound duct 42 has a first extension portion 42a that extends in the front-to-rear direction (an example of a first direction) along the vehicle body side frames 22 to a midpoint between the front and rear of the vehicle body 2. The outbound duct 42 also bends at a midpoint between the front and rear of the vehicle body 2 on the vehicle body side frames 22, and extends left and right outward from the vehicle body 2 towards the running structures 3 that are on the left and right outer sides. In other words, the outbound duct 42 has this bent portion as the rear end of the extension portion 42a, and has an extension portion (second extension portion) 42b that extends from the rear end of the extension portion 42a in a left-right direction that is different from the front-to-rear direction.

[0168] The above-described configuration of the outward duct 42 is the same in the second embodiment shown in FIGS. 15 to 18 and the third embodiment shown in FIGS. 19 and 20.

[0169] Meanwhile, a return duct 43 extends from the side battery 37 to return the cooling air that has cooled the side battery 37 to the air conditioning unit 51. Specifically, the return duct 43 extends from the cooling air outlet 36b (see FIG. 11 ) of the side battery case 36, which is the housing that houses the side battery 37.

[0170] 19 and 20 , the return duct 43 extends to the vicinity of the air intake 51a of the air conditioning unit 51 and returns the cooling air after cooling the side battery 37 of the traveling structure 3 to the air conditioning unit 51 in the vehicle body 2. That is, in this embodiment, the return duct 43 corresponds to the duct that extends from the cooling device (air conditioning unit 51) to the cooled device (side battery 37) among multiple ducts that circulate cooling air between the cooling device (air conditioning unit 51) and the cooled device (side battery 37).

[0171] For this reason, in this embodiment (first embodiment) and third embodiment, the return duct 43 first has an extension portion 43b that extends in a left-right direction different from the front-rear direction (first direction) from the side battery case 36 provided on the traveling structure 3 toward the vehicle body 2 on the left and right inner sides thereof. This extension portion 43b is disposed parallel to the extension portion (second extension portion) 42b of the outward duct 42 that also extends in the left-right direction.

[0172] Furthermore, in this embodiment (first embodiment) and 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 conditioning case 40, and returns cooled air from the outlet end to the air intake port 51a via the air conditioning chamber 40a inside the air conditioning case 40. In the upper part of the vehicle body 2, the return duct 43 has an extension portion (first extension portion) 43a that extends in the front-to-rear direction from the front end (first end) of the vehicle body 2 to the midpoint between the front and rear, and this extension portion 43a and the extension portion (first extension portion) 42a of the outward duct 42 are arranged in parallel.

[0173] In the second embodiment shown in Figures 15 and 16 and described later, the return duct 43 does not extend to the air conditioning unit 51, but is connected to the center battery case 24, and the air that has cooled the side battery 37 is merged with the air that has cooled the center battery 50 before being returned to the air intake 51a of the air conditioning unit 51.

[0174] That is, in the second embodiment, the return duct 43 is connected to the center battery case 24 supported by the vehicle body 2, and therefore has a left-right extension portion 43b, but does not have a front-rear extension portion (first extension portion) 43a which is arranged on the upper part of the vehicle body 2.

[0175] On the other hand, in the second embodiment, the outward duct 42 extends from the discharge manifold 41b to the cooling air inlet 36a of the side battery case 36, as in the first embodiment, and has an extension portion 42a in the fore-and-aft direction at the top of the vehicle body 2, and an extension portion 42b in the left-and-right direction from the vehicle body 2 to the running structure 3, as in the first embodiment.

[0176] That is, as a structure common to the first embodiment and the second embodiment, of the outbound duct 42 and the return duct 43, at least the outbound duct 42 has an extension portion (first extension portion) 42a extending in the fore-and-aft direction (first direction) as described above, and further has an extension portion 42b extending in a left-right direction different from the fore-and-aft direction at a midpoint between the fore and aft of the vehicle body 2. Furthermore, the return duct 43 has at least an extension portion 43b extending in a left-right direction different from the fore-and-aft direction in which the extension portion 42a of the outbound duct 42 extends, and the extension portion 43b is disposed parallel to the extension portion (second extension portion) 42b of the outbound duct 42 extending in the left-right direction.

[0177] Here, the side battery case 36 will be described. As shown in Fig. 11 , the side battery case 36 of each traveling structure 3 has a cooling air inlet 36a at the bottom of its front end face 36f and a cooling air outlet 36b at the top of its rear end face 36r. In Fig. 11 , "36s" indicates the left and right outer surfaces of the side battery case 36 between the front end face 36f and the rear end face 36r.

[0178] The cooling air inlet 36a connected to the outward duct 42 is provided at the bottom of the side battery case 36, and the cooling air outlet 36b connected to the return duct 43 is provided at the top of the side battery case 36. This is to ensure that the cooled air can be efficiently discharged from the side battery case 36 so that the heated air after cooling the side battery 37 inside the side battery case 36 does not heat the cooling air before cooling.

[0179] Furthermore, one of the cooling air inlet 36a and the cooling air outlet 36b is positioned closer to the inside on the left or right, and the other closer to the outside on the left or right, so that the cooling air flows diagonally from the cooling air inlet 36a at the front end to the cooling air outlet 36b at the rear end within the side battery case 36 in a plan view, thereby maximizing the cooling effect of the side battery 37.

[0180] The layout of the cooling air inlets 36a connected to the outward ducts 42 and the cooling air outlets 36b connected to the return ducts 43 in the side battery cases 36 is not limited to the layout shown in Fig. 11. For example, at least one of the cooling air inlets 36a and the cooling air outlets 36b may be provided on the left or right outer surface 36s or the left or right inner surface opposite thereto.

[0181] In this embodiment, taking into consideration the routing of the ducts, the cooling air inlet 36a and the outward duct 42 connected thereto are positioned closer to the inside on the left and right, and the cooling air outlet 36b and the return duct 43 connected thereto are positioned closer to the outside on the left and right. The side battery case 36 in Figure 11 is a left-side battery case 36L, as the cooling air inlet 36a is positioned closer to the right and the cooling air outlet 36b is positioned closer to the left.

[0182] As shown in FIG. 2 etc., a front inverter 6F is provided along the front end surface 36f of the side battery case 36 on the left and right outside of the forward duct 42 connected to the cooling air inlet 36a of the side battery case 36, and a rear inverter 6R is provided along the rear end surface 36r of the side battery case 36 on the left and right inside of the return duct 43 connected to the cooling air outlet 36b of the side battery case 36.

[0183] The side battery 37, which is the equipment to be cooled, includes a left side battery 37L, which is the left equipment to be cooled and arranged on the left running structure 3L, and a right side battery 37R, which is the right equipment to be cooled d and arranged on the right running structure 3R.

[0184] Corresponding to this, as a structure common to the first to third embodiments, the multiple ducts that circulate cooling air between the air conditioning unit 51 (cooling device) and the left and right side batteries 37L, 37R (equipment to be cooled) include a left outgoing duct 42L that extends to the left side battery 37L and a right outgoing duct 42R that extends to the right side battery 37R in order to supply the cooling air discharged from the air conditioning unit 51 to the left and right side batteries 37L, 37R, and a left return duct 43L that extends from the left side battery 37L and a right return duct 43R that extends from the right side battery 37R in order to return the cooling air to the air conditioning unit 51 after cooling the left and right side batteries 37L, 37R.

[0185] Among these outbound ducts 42L, 42R and return ducts 43L, 43R, at least the left outbound duct 42L and the right outbound duct 42R extend from the air conditioning unit 51 to the left-side battery 37L and the right-side battery 37R, respectively, and are ducts having an extension portion (first extension portion) 42a extending in the front-rear direction (first direction) in the range from the front end (first end) to the front-rear midpoint (midpoint). In addition, the extension portion (second extension portion) 42b of the left outbound duct 42L extending in a left-right direction different from the front-rear direction (first direction) and the extension portion (second extension portion) 42b of the right outbound duct 42R extending in a left-right direction different from the front-rear direction (first direction) extend in opposite left-right directions relative to the vehicle body 2.

[0186] The left return duct 43L and the right return duct 43R each have an extension portion 43b that extends in a left-right direction different from the fore-and-aft direction (first direction), and the extension portion 43b of the left return duct 43L that extends in a left-right direction different from the fore-and-aft direction (first direction) and the extension portion 43b of the right return duct 43R that extends in a left-right direction different from the fore-and-aft direction (first direction) extend in opposite left-right directions relative to the vehicle body 2.

[0187] Below, we will explain in detail the specific piping routes of the outbound duct 42 and the return duct 43 in the first embodiment shown in Figures 1 to 10, etc., and the layout of multiple ducts consisting of left and right outbound ducts 42L, 42R and left and right return ducts 43L, 43R.

[0188] An outgoing duct 42 is piped from the discharge manifold 41b to the cooling air inlet 36a of the side battery case 36 of each traveling structure 3, passing through the upper part of the vehicle body 2 (the upper part of the vehicle body side frame 22).

[0189] That is, the left outgoing duct 42L is piped from the left portion of the discharge manifold 41b to the cooling air inlet 36a of the left-side battery case 36L of the left traveling structure 3L, passing through the upper left portion of the vehicle body 2 (above the left vehicle body side frame 22L). On the other hand, the right outgoing duct 42R is piped from the right portion of the discharge manifold 41b to the cooling air inlet 36a of the right-side battery case 36R of the right traveling structure 3R, passing through the upper right portion of the vehicle body 2 (above the right vehicle body side frame 22R).

[0190] In addition, a return duct 43 is piped from the cooling air outlet 36b of the side battery case 36 of each running structure 3 to the upper end of the air conditioner case 40, passing through the upper part of the vehicle body 2 (the upper part of the vehicle body central frame 21).

[0191] That is, the left return duct 43L is piped 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, passing through the upper left part of the vehicle body 2 (upper left part of the vehicle body center frame 21). On the other hand, the right return duct 43R is piped 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, passing through the upper right part of the vehicle body 2 (upper right part of the vehicle body center frame 21).

[0192] As can be seen from the plan view of FIG. 9, the plates 42L, 42R, 43L, and 43R have extending portions 42a and 43a that extend linearly in the front-rear direction.

[0193] These extensions 42a, 43a are piped parallel to each other in the fore-and-aft direction in the upper part of the vehicle body 2, from the front of the vehicle body 2 to a position that is midway between the front and rear (a position that corresponds in the fore-and-aft direction to the side battery cases 36 (and further to the front ends of the side battery cases 36) on the left and right running structures 3).

[0194] Regarding the left-right arrangement of the extension portions 42a, 43a of ducts 42L, 42R, 43L, 43R, the extension portion 43a of the left return duct 43L and the extension portion 43a of the right return duct 43R are arranged parallel to each other on the left and right sides at the top of the vehicle body center frame 21, and the extension portion 42a of the left outward duct 42L is arranged on the left vehicle body side frame 22L to the left of the extension portion 43a of the left return duct 43L, and the extension portion 42a of the right outward duct 42R is arranged on the right vehicle body side frame 22R to the right of the right return duct 43R.

[0195] The left outbound duct 42L extends upward and to the left from its front end connected to the discharge manifold 41b arranged on the vehicle center frame 21, bends rearward above the left vehicle side frame 22L, and then extends a longitudinal extension portion 42a above the left vehicle side frame 22L.

[0196] Furthermore, in the fore-and-aft direction, the left outbound duct 42L bends at approximately a right angle in a plan view from a fore-and-aft extension portion 42a located on the left body side frame 22L at a position slightly forward of the front end of the left side battery case 36L of the left running structure 3L, extends a left-right extension portion 42b to the left, crosses over to the left running frame 30L, bends at a position just forward of the left side battery case 36L, extends downward, and is connected to the cooling air inlet 36a at the front end of the left side battery case 36L.

[0197] The right outbound duct 42R extends upward to the upper right from its front end connected to the discharge manifold 41b arranged on the vehicle center frame 21, bends rearward above the right vehicle side frame 22R, and then extends a longitudinal extension portion 42a above the right vehicle side frame 22R.

[0198] Furthermore, in the fore-and-aft direction, the right outbound duct 42R bends at approximately a right angle in a plan view from a fore-and-aft extension portion 42a located on the right body side frame 22R at a position slightly forward of the front end of the right side battery case 36R of the right running structure 3R, extends to the right via a left-right extension portion 42b, crosses over to the right running frame 30R, bends at a position just in front of the right side battery case 36R, extends downward, and is connected to the cooling air inlet 36a at the front end of the right side battery case 36R.

[0199] The left return duct 43L bends at approximately a right angle in a plan view from a longitudinal extension portion 43a arranged on the vehicle body central frame 21 at a position slightly rearward of the front end of the left side battery case 36L of the left running structure 3L, extends to the left via a left-right extension portion 43b, crosses over the left vehicle body side frame 22L and reaches the left running frame 30L, bends further and extends rearward above the left side battery case 36L, bends again behind 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.

[0200] The right return duct 43R bends at approximately a right angle in a plan view from a longitudinal extension portion 43a arranged on the vehicle body central frame 21 at a position slightly rearward of the front end of the right side battery case 36R of the right running structure 3R, extends to the left via a lateral extension portion 43b, crosses over the right vehicle body side frame 22R and reaches the right running frame 30R, bends further and extends rearward above the right side battery case 36R, bends again behind 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.

[0201] The work vehicle 1 shown in Figures 1 to 10 has a structure that allows the "vehicle shape" to be changed, and is provided with a duct that can expand and contract in response to such "changes in vehicle shape."

[0202] The ducts 42, 43 serving as the cooling air passages described above are extendable ducts of this kind. Note that other extendable ducts are also possible; for example, if the work vehicle 1 is equipped with an engine as a prime mover, the intake pipe or exhaust pipe of the engine may be used as such extendable ducts. Furthermore, any cooling medium may be circulated through the ducts, and in addition to the air serving as the cooling air described above, a refrigerant gas or the like may also be considered.

[0203] Here, "changing the vehicle shape" can be considered to mean the relative movement of "a first section and a second section linked to be able to move relative to each other" provided on the work vehicle 1, but is not limited to this form. For example, if any section of the work vehicle (such as a cover covering the frame) is made of a material that has plasticity, stretchability, elasticity, or the like, and the section itself deforms due to its physical properties, or if any section of the work vehicle (such as a roof member covering a passenger seat when the vehicle is equipped with a passenger seat) is detachable, and the vehicle shape is changed based on the attachment or detachment of the section, these could also be considered "changing the vehicle shape."

[0204] Furthermore, in the above-described structure, the "first part and second part connected to each other so that they can move relative to each other" refers to the center battery case (front main body case) 24 and the body frame structure 20 (body center frame 21, etc.) which are connected to each other so that they can move relative to each other in the fore-and-aft direction, the body center frame 21 and body side frames 22 (left body side frame 22L, right body side frame 22R) which are connected to each other so that they can move relative to each other in the left-right direction, and the body 2 (body side frame 22) and running structure 3 (running frame 30) which are connected to each other so that they can move relative to each other in the up-and-down direction.

[0205] However, the "first part and second part linked to be able to move relative to each other" are not limited to the above. For example, if a work implement such as a rotary tiller is connected to the vehicle body 2 via a three-point linkage type coupling device 60, the vehicle body 2 and the work implement move relative to each other in the vertical direction due to the extension and contraction of a lift cylinder 61 provided on the coupling device 60, and such a vehicle body 2 and work implement can also be considered the "first part" and the "second part." Furthermore, the shape of the work vehicle 1 changes depending on whether the coupling device 60 or the work implement is attached. In this way, the "first part" and the "second part" can be any part of the work vehicle 1 that is linked to be able to move relative to each other.

[0206] Furthermore, when the "change in vehicle shape" is "relative movement between a first part and a second part that are linked so that they can move relative to each other," a "duct that can expand and contract in response to a change in vehicle shape" can be considered to be "a duct that extends across the first part and the second part that are linked so that they can move relative to each other, and has an expansion / contraction section that can expand and contract in response to the relative movement between the first part and the second part."

[0207] It is also conceivable that one of the aforementioned "first portion and second portion linked to be able to move relative to each other" is the first portion of the vehicle body 2 and the other is the second portion of the vehicle body 2, and that the aforementioned expansion and contraction portion is provided in a portion of the duct that is disposed between the first and second portions of the vehicle body 2. Alternatively, it is conceivable that one of the first portion and the second portion is the vehicle body 2, and the other is the traveling structure 3.

[0208] In the above-described structure, the "portion disposed between the first and second portions of the vehicle body 2" may be a portion disposed between the discharge manifold 41b (movable 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 (the left vehicle body side frame 22L, the right vehicle body side frame 22R), but is not limited to these. For example, the vehicle body center frame 21 may be divided into a front portion and a rear portion, and these front and rear portions may be connected to each other so as to be movable relative to each other in the fore-and-aft direction, and an expansion / contraction portion may be provided in the corresponding portion of a duct extending between the front and rear portions.

[0209] Furthermore, the duct only needs to have at least one expandable section in the section disposed between the first and second sections of the car body 2, or in the section disposed between the car body 2 and the running structure 3, and multiple expandable sections may be provided in that section. Furthermore, such expandable sections are not limited to those provided in series in that section, and for example, the duct may be U-shaped, with multiple sections disposed between the first and second sections of the car body 2, or multiple sections disposed between the car body 2 and the running structure 3, and in such cases, an expandable section may be provided in each of the multiple sections.

[0210] The outward duct 42 and the return duct 43 described above, and the return duct 44 in the third embodiment described below, correspond to the ducts having the expansion and contraction sections described above. The structure of the expansion and contraction sections of each duct will be described in detail below.

[0211] As shown in Figure 2 etc., the front ends of the ducts 42, 43 extend forward from the front end of the upper part of the body frame structure 20, bend downward from the extensions 42a, 43a, and are connected to the discharge manifold 41b provided in the air conditioning unit 51 and the air conditioning case 40 (or intake manifold).

[0212] The air conditioner case 40 is connected to 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 longitudinal direction relative to the body frame structure 20, the air conditioner case 40 and the discharge manifold 41b also move integrally with the center battery case 24.

[0213] The ducts 42, 43 have telescopic sections 42c, 43c that can be extended and contracted in the fore-and-aft direction at their longitudinal extension sections 42a, 43a, respectively. As shown in Figure 8, when the battery movement actuator 81 is actuated or the like, the air conditioning case 40 that houses the air conditioning unit 51 and the discharge manifold 41b together with the center battery case 24 move in the fore-and-aft direction relative to the body frame structure 20, and the telescopic sections 42c, 43c extend and contract in response to this movement.

[0214] That is, the ducts 42, 43 extend over the discharge manifold 41b and the air conditioner case 40 (first portion), which are linked to the body frame structure 20 (second portion) so as to be movable relative to each other in the fore-and-aft direction, and have telescopic portions 42c, 43c that can expand and contract in accordance with the relative movement in the fore-and-aft direction. That is, the outbound duct 42 has the telescopic portion 42c that can expand and contract in the fore-and-aft direction in a portion of the fore-and-aft direction that is located between the discharge manifold 41b (first portion of the body 2) and the body frame structure 20 (second portion of the body 2), and the return duct 43 has the telescopic portion 43c that can expand and contract in the fore-and-aft direction in a portion of the fore-and-aft direction that is located between the air conditioner case 40 (first portion of the body 2) and the body frame structure 20 (second portion of the body 2).

[0215] The outward duct 42 has a front end connected to the discharge manifold 41b, which is forward of the longitudinal extension 42a, extending upward and outward on the left and right sides, and is bridged from the vehicle body center frame 21 to the vehicle body side frames 22. Note that the discharge manifold 41b is a part that can move relative to the vehicle body side frames 22 as one unit 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, and the front end of the outward duct 42 that bridges between the discharge manifold 41b and the vehicle body side frames 22 is therefore bridged between the vehicle body center frame 21 and the vehicle body side frames 22.

[0216] On the other hand, the return duct 43 has an extension portion 43 a extending in the front-rear direction, which is bent at the rear end to form an extension portion 43 b extending in the left-right direction, and which spans from the vehicle body center frame 21 to the vehicle body side frame 22 .

[0217] In this way, the ducts 42, 43 extend in the left-right direction and have telescopic sections 42d, 43d that can be extended and contracted in the left-right direction at the sections that span from the vehicle body center frame 21 to the vehicle body side frames 22. As can be seen in Figure 9, when the vehicle body side frames 22 move in the left-right direction relative to the vehicle body center frame 21 due to operation of the width changing cylinder 8, etc., the telescopic sections 42d, 43d extend and contract in response to this movement.

[0218] In other words, the ducts 42, 43 extend across the vehicle body central frame 21 (first portion) and the vehicle body side frame 22 (second portion), which are connected to each other so that they can move relative to each other in the left-right direction, and are ducts that have extension / contraction sections 42d, 43d in the left-right portion located between the vehicle body central frame 21 (first portion of the vehicle body 2) and the vehicle body side frame 22 (second portion of the vehicle body 2) that can expand and contract in accordance with the relative movement in the left-right direction.

[0219] The ducts 42, 43 extend further outward to the left and right from the expansion / contraction sections 42d, 43d on the vehicle side frames 22, are bridged to the running structures 3 on the left and right outer sides of the vehicle body 2, and are connected to the side battery cases 36. The ducts 42, 43 are bridged over the upper part of the running frame 30, then bend and extend downward to the cooling air inlet 36a and cooling air outlet 36b, and have expansion / contraction sections 42e, 43e that can expand and contract in the vertical direction. As can be seen in Figure 8, when the vehicle body 2 moves up and down relative to the running structures 3 due to operation of the vehicle body lifting cylinder 9, etc., the expansion / contraction sections 42e, 43e expand and contract in response to the movement.

[0220] In other words, ducts 42, 43 extend across the vehicle body 2 (first part) and the running structure 3 (second part) arranged on the left and right sides of the vehicle body 2, which are connected to each other so that they can move relative to each other in the vertical direction, and are ducts having extension and contraction sections 42e, 43e in the vertical part arranged between the vehicle body 2 and the running structure 3 that can expand and contract in accordance with the relative movement in the vertical direction.

[0221] In addition, the work vehicle 1 is equipped with a running structure 3 provided on the side of the vehicle body 2, the vehicle body 2 being movable relative to the running structure 3, and the ducts 42, 43 have multiple expansion and contraction sections provided in a section located between the first and second sections of the vehicle body 2 and in a section located between the vehicle body 2 and the running structure 3.

[0222] In other words, the outbound duct 42 is a duct having multiple expansion and contraction sections 42c, 42e provided in a section arranged between the discharge manifold 41b (first section) of the vehicle body 2 and the vehicle body frame structure 20 (second section), and in a section arranged between the vehicle body 2 and the running structure 3, and also having multiple expansion and contraction sections 42d, 42e provided in a section arranged between the vehicle body central frame 21 (first section) and the vehicle body side frame 22 (second section), and in a section arranged between the vehicle body 2 and the running structure 3.

[0223] In addition, the return duct 43 is a duct having multiple expansion and contraction sections 43c, 43e in the fore-and-aft section located between the air conditioning case 40 (first section) of the vehicle body 2 and the vehicle body frame structure 20 (second section), and in the section located between the vehicle body 2 and the running structure 3, and also having multiple expansion and contraction sections 43d, 43e in the section located between the vehicle body central frame 21 (first section) and the vehicle body side frame 22 (second section) and in the section located between the vehicle body 2 and the running structure 3.

[0224] As described above, the ducts 42, 43 may have a plurality of expansion / contraction sections in the section disposed between the first section and the second section of the vehicle body 2, or may have a plurality of such sections, each with an expansion / contraction section. The same applies to the section disposed between the vehicle body 2 and the running structure 3.

[0225] Furthermore, when the work vehicle 1 is equipped with a cooling device provided in the first part or the second part, and equipment to be cooled that is provided on the running structure 3 and cooled by a cooling medium supplied by the cooling device, the ducts having multiple expansion sections provided in the part located between the first part and the second part of the body 2 and the part located between the body 2 and the running structure 3 may be extended between the cooling device and the equipment to be cooled as a passage for the cooling medium.

[0226] In this embodiment, as described above, the ducts 42, 43 having multiple expansion and contraction sections are extended between the air conditioning unit 51 provided in the air conditioning case 40 corresponding to the first or second part of the vehicle body 2 and the side battery 37 provided on the running structure 3.

[0227] In addition, the vehicle body 2 has a third part that is movable relative to the second part, and the ducts 42, 43 have multiple expansion and contraction sections in a part that is located between the first part and the second part of the vehicle body 2 and in a part that is located between the second part and the third part of the vehicle body 2.

[0228] The outbound duct 42 is a duct having multiple expansion and contraction sections 42c, 42d in a front-to-rear portion located above the vehicle side frame 22 and in a left-to-right portion located between the discharge manifold 41b and the vehicle side frame 22.

[0229] On the other hand, the return duct 43 is a duct having multiple expansion and contraction sections 43c, 43d provided in a section arranged between the air conditioning case 40 (first section) of the vehicle body 2 and the vehicle body central frame 21 (second section), which is part of the vehicle body frame structure 20, and in a section arranged between the vehicle body central frame 21 (second section) and the vehicle body side frame 22 (third section).

[0230] As described above, the ducts 42, 43 may have a plurality of expansion / contraction sections in the section disposed between the first section and the second section of the vehicle body 2, or may have a plurality of such sections, each with an expansion / contraction section. The same applies to the section disposed between the second section and the third section.

[0231] In addition, in this embodiment, the vehicle body 2 has three parts, the first to third parts, that are linked together to be able to move relatively, but it is sufficient that there are at least three parts that correspond to these first to third parts, and the above structure can be applied even if there are four or more parts. Therefore, the expansion / contraction parts provided in such parts of the vehicle body 2 are not limited to two, such as the expansion / contraction parts 42c and 42d or the expansion / contraction parts 43d and 43d, like the ducts 42 and 43, and may be provided according to the number of corresponding parts.

[0232] In addition, when the work vehicle 1 is equipped with a running structure 3 provided on the side of the body 2, an air conditioning unit 51 (cooling device) provided in an air conditioning case 40 (first part of the body 2), and a side battery 37 (equipment to be cooled) arranged on the running structure 3 and cooled by the cooling medium supplied by the air conditioning unit 51, the return duct 43 extends in the fore-and-aft direction from the air conditioning unit 51 to the body center frame 21 (second part of the body 2) as a passage for the cooling medium, bends at the body center frame 21, extends in the left-right direction from the body center frame 21 to the body side frame 22 (third part of the body 2), and extends in the up-and-down direction from the body side frame 22 to the side battery 37.

[0233] As can be seen in Figure 2 and other figures, the first extension 43a of the return duct 43 on the vehicle body center frame 21 is piped immediately next to the left and right inner sides of the vehicle body side frame 22, so the outgoing duct 42 extends immediately from the discharge manifold 41b upward and outward to the left and right of the vehicle body side frame 22, and has a left-right expandable section 42d at this outward extension, and the first front-rear extension 42a is piped immediately next to the left and right outer sides of the first extension 43a of the return duct 43. Since the outgoing duct 42 has an expandable section 42c at this first extension 42a, the front-rear expandable section 42c is located rearward of the left-right expandable section 42d. The outgoing duct 42 bends behind the front-rear expandable section 42c to extend a second left-right extension 42b toward the running structure 3, and has a vertical expandable section 42e in the portion spanning the running structure 3.

[0234] 2 (at the middle of the vehicle body center frame 21), the first extension 42a of the outgoing duct 42 can also be arranged above the vehicle body center frame 21, on the left and right inner side of the vehicle body side frames 22. In this case, similar to the piping route of the ingoing duct 43 described above, the outgoing duct 42 as a passage for the cooling medium can be arranged along a route that extends in the front-rear direction from the air conditioning 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, extends in the left-right direction from the vehicle body center frame 21 to the vehicle body side frames 22 (the third part of the vehicle body 2), and then extends in the up-down direction from the vehicle body side frames 22 to the side battery 37.

[0235] As described above, the ducts 42, 43 have expandable and contractible sections 42c to 42e, 43c to 43e, and therefore can maintain a piping state without being separated between the air conditioning unit 51 and the side battery case 36 regardless of deformation of the vehicle body 2 or relative movement between the vehicle body 2 and the running structure 3.

[0236] Thus, in the work vehicle 1, a single duct 42, 43 has multiple sections that span across separate parts that are linked to be able to move relative to each other (for example, the vehicle body 2 and the running structure 3, the vehicle body central frame 21 and the vehicle body side frames 22, etc.), and these multiple sections have extensions. In this embodiment, each duct 42, 43 has three sections that span across separate parts that are linked to be able to move relative to each other, and has three extensions 42c to 42e, 43c to 43e corresponding to these, but this is not limited to this, and the number of extensions of each duct may be more than three or less than three.

[0237] Furthermore, the direction of extension and contraction of each extension section corresponds to the relative movement direction of the different sections across which the duct is spanned, as described above, and in this embodiment, the relative movement directions of the sections across which the three sections are spanned are different, and of each of ducts 42, 43, extension sections 42c, 43c extend in the front-to-rear direction, extension sections 42d, 43d extend in the left-to-right direction, and extension sections 42e, 43e extend in the up-to-down direction, making one duct extendable in various directions. However, the extension and contraction directions of multiple extension sections in one duct are not limited to these, and for example, multiple extension sections in one duct may be extendable in the same direction.

[0238] In other words, when each duct has multiple extension sections, the number of extension sections and the extension direction of the extension sections are determined according to the type of structure that changes the vehicle shape of the work vehicle 1 described above, and also according to the route that each duct takes to extend in accordance with the cooling device (in this embodiment, the air conditioning unit 51) and the equipment to be cooled (in this embodiment, the side battery 37), and are not limited to the above-mentioned embodiment.

[0239] Instead of the telescopic structure described above, it is also possible to configure the ducts 42, 43, which are made of a flexible material, so that they are pre-flexed in preparation for deformation of the car body 2 and relative movement between the car body 2 and the running structure 3, so that as the car body 2 rises, for example, the bent portions change to a straight, extended state.However, in this case, when the car body 2 is not raised, the ducts 42, 43 must be given a flexure that causes them to bulge significantly from the car body 2, which makes it difficult to achieve compact piping.

[0240] In this regard, in the case of the ducts 42, 43 according to this embodiment, when the vehicle body 2 is not raised, the extension / contraction sections 42e, 43e are not bent but are in a contracted state, so that they are kept in line with the vehicle body side frame 22 and the running frame 30, thereby enabling compact piping to be achieved.

[0241] The expansion / contraction sections 42c to 42e, 43c to 43e of the ducts 42, 43 may be formed, for example, from bellows hoses, but are not limited to this and may be formed from any material as long as they are structured to be expandable and contractible in response to the relative movement between the center battery case 24 and the body frame structure 20, the relative movement between the body central frame 21 and the body side frame 22, and / or the relative movement between the body 2 and the running structure 3 as described above.

[0242] Furthermore, various considerations can be given to the range and / or extent of the stretchable portion to be provided in the portion of each duct where the stretchable portion should be provided. For example, when providing the stretchable portion 43d in the left-right extending portion 43b of the return duct 43, which is stretchable in the left-right direction in response to the relative movement between the vehicle body center frame 21 and the vehicle body side frame 22, the stretchable portion 43d may be divided into left-right outer portions and left-right inner portions, and a non-stretchable portion of the return duct 43 may be interposed between these two stretchable portions. This shortens the axial length of each portion of the stretchable portion 43d, making it possible to use a short bellows hose in each portion.

[0243] Next, a second embodiment of the air-cooling system for the work vehicle 1 will be described with reference to Figures 15 and 16. Note that a description of the same configuration as in the first embodiment will be omitted. Furthermore, members and parts denoted with the same reference numerals as those used in the first embodiment have the same configuration or function as the corresponding members and parts in the first embodiment.

[0244] The air-cooling system shown in Figures 15 and 16 is an embodiment of an air-cooling system that is applied to a work vehicle 1 that includes a cooling device, first and second equipment to be cooled by cooling air discharged from the cooling device, a first cooling housing that houses the first equipment to be cooled, and a second cooling housing that houses the second equipment to be cooled, and that has a structure in which the first cooling housing is provided with an intake port for taking in air that is discharged from the second cooling housing after cooling the second equipment to be cooled.

[0245] That is, in this embodiment, the cooling device is an air conditioning unit 51, the first cooling target equipment is a center battery 50, the first cooling housing is a center battery case 24, the second cooling target equipment is a side battery 37, the second cooling housing is a side battery case 36, and the center battery case 24 is provided with an intake 24h for taking in air discharged from the side battery case 36.

[0246] However, as described above in the explanation of the duct structure, various cooling devices and cooled equipment are possible. Furthermore, there are no limitations on which of the multiple cooled equipment in the work vehicle 1 is the first cooled equipment and which is the second cooled equipment. For example, the side battery 37 may be the first cooled equipment and the center battery 50 may be the second cooled equipment, and an intake port for taking in air discharged from the center battery case 24 may be provided in the side battery case 36 that houses the side battery 37.

[0247] Alternatively, one of the first cooling target device and the second cooling target device may be the left-side battery 37L and 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 and the other may be the right-side battery case 36R.

[0248] Alternatively, the first device to be cooled and / or the second device to be cooled may be something other than a battery.

[0249] In this embodiment, a cooling air passage 24c is formed within the center battery case 24 (first cooling housing) to direct cooling air from the air conditioning unit 51 (cooling device) onto the center battery 50 (first cooling target device), and an exhaust air passage 24d is formed to discharge the air after cooling the center battery 50 into the air conditioning unit 51, and air from the side battery case 36 (second cooling housing) introduced into the center battery case 24 through the intake 24h is merged with the air in the exhaust air passage 24d.

[0250] Also provided within center battery case 24 (first cooling housing) are a first air guide device that guides air from cooling air passage 24c to exhaust air passage 24d, and a second air guide device that guides air from intake 24h to exhaust air passage 24d. In this embodiment, the first air guide device is fan 45, and the second air guide device is fan 46, but they are not limited to such fans and may be guide members such as simple plates or ribs integrally molded on the housing.

[0251] Furthermore, within the center battery case 24 (first cooling housing), a partition plate is provided above the first cooling target equipment, and the space below the partition plate 24e within the center battery case 24 is the cooling air passage 24c, and the space above the partition plate 24e is the exhaust air passage 24d.

[0252] Within the center battery case 24 (first cooling housing), a vertical communication passage 24g is provided along the end of the partition plate 24e, connecting the outlet of the cooling air passage 24c with the entrance of the exhaust air passage 24d, and a fan 45 (first air guide device) is provided at the exit of the cooling air passage 24c to guide air from the cooling air passage 24c to the bottom of the communication passage 24g, and an intake 24h and a fan 46 (second air guide device) are provided at the top of the communication passage 24g to guide the air introduced through the intake 24h to the entrance of the exhaust air passage 24d.

[0253] In the air-cooled system according to the second embodiment, the return ducts 43 (left return duct 43L and right return duct 43R) for returning the cooling air to the air conditioning unit 51 after cooling the side battery 37 are structured so that the cooling air is returned into the center battery case 24 rather than directly to the air conditioning unit 51 (intake manifold 76), and are therefore shorter than those in the first embodiment.

[0254] 15, an intake 24h is provided at the top 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 24h. Note that a pair of intakes 24h may be provided, and the outlet ends of the left return duct 43L and the right return duct 43R may be connected to the respective intakes 24h, or a single intake 24h may be provided, and the left return duct 43L and the right return duct 43R may be joined together and then connected to the intake 24h.

[0255] The intake 24h faces the upper part of the communication passage 24g inside the center battery case 24, i.e., the entrance of the exhaust passage 24d, and is configured so that the air flows from the intake 24h to the exhaust passage 24d in a straight horizontal direction, allowing the air to flow smoothly from the intake 24h to the exhaust passage 24d.

[0256] In this way, the cooling air (air) after cooling the left and right side batteries 37L, 37R passes from the left and right side battery cases 36L, 36R through the left and right return ducts 43L, 43R and is introduced into the center battery case 24 through the intake 24h, where it merges with the cooling air (air) after cooling the center battery 50 that has entered the connecting passage 24g from the cooling air passage 24c and rises, and is discharged from the cooling air outlet 24b via the exhaust passage 24d and returned to the air intake 51a of the air conditioning unit 51.

[0257] Furthermore, within the center battery case 24, the exhaust air passage 24d may be divided (separated) into a passage for air from the intake 24h and a passage for air from the cooling air passage 24c, and the air that passes through these passages may merge after leaving the cooling air outlet 24b and be drawn into the air intake 51a.

[0258] To divide the exhaust passage 24d, for example, a parallel partition plate may be provided above the partition plate 24e to divide the exhaust passage 24d into two upper and lower passages, the rear end of this partition plate may be connected to the rear end wall of the center battery case 24, and an intake 24h may be provided in the rear end wall of the center battery case 24 above this partition plate.

[0259] In this way, the partition plate provided above partition plate 24e completely separates the air from intake 24h after cooling the side battery 37 from the air from cooling air passage 24c after cooling the center battery 50, and the air from exhaust passage 24d after cooling the side battery 37 passes through a passage above the partition plate, while the air from exhaust passage 24d after cooling the center battery 50 passes through a passage below the partition plate and is discharged into the air-conditioning compartment 40a through cooling air outlet 24b.

[0260] Alternatively, the exhaust air passage 24d may be divided into left and right passages, one of which is connected to the intake port 24h to serve as a passage for air after cooling the side battery 37, and the other is connected to the cooling air passage 24c to serve as a passage for air after cooling the center battery 50.

[0261] In addition, in the second embodiment, the outlet ends of the left return duct 43L and the right return duct 43R are connected to the rear end of the center battery case 24, so as can be seen in Figure 16, the longitudinal extension portions 43a of the left return duct 43L and the right return duct 43R that were bridged over the vehicle center frame 21 in the first embodiment are omitted.

[0262] That is, in the first embodiment, the extensions 42a, 43a of the four ducts 42L, 42R, 43L, 43R are piped in parallel at the top of the body frame structure 20, whereas in the second embodiment, only the extensions 42a of the two ducts 42L, 42R are piped in parallel at the top of the body frame structure 20 (left and right body side frames 22L, 22R).

[0263] That is, in the second embodiment shown in FIGS. 15 and 16, the return duct 43 is a duct that extends from the air conditioning unit 51 (cooling device) to the side battery 37 (equipment to be cooled) and has an extension portion (first extension portion) 43a that extends in the front-rear direction (the first direction), and the extension portion (first extension portion) 42a of the outward duct 42 and the extension portion (first extension portion) 43a of the return duct 43 are arranged in parallel, but the vehicle body 2 has an air A center battery 50 (second cooling target equipment) is provided which is cooled by cooling air from the air conditioning unit 51, and an exhaust passage 24d is formed within the center battery case 24, which is a housing that houses the center battery 50 (second cooling target equipment), for discharging the cooling air after cooling the center battery 50 to the air conditioning unit 51, and the return duct 43 is connected to the center battery case 24 and communicates with the exhaust passage 24d within the center battery case 24.

[0264] The reduction in the number of ducts in this way ensures that space is available for arranging equipment other than the ducts above the vehicle body frame structure 20. For example, while in the first embodiment it was necessary to attach the situation detection device 10 via stays 10d that straddled the extensions 43a of the return ducts 43L, 43R, in the second embodiment, a large area not covered by ducts is secured on the upper end surface of the support member 23 provided directly below the vehicle body center frame 21 between the extensions 42a of the left and right outgoing ducts 42L, 42R piped on the left and right vehicle body side frames 22L, 22R, so that the situation detection device 10 can be attached directly to the upper end surface of the support member 23 without providing a stay for straddling the ducts.

[0265] Furthermore, in this embodiment, in addition to the fan 45 provided in the first embodiment, a fan 46 is provided inside the center battery case 24 at an upper portion of the communication passage 24g, facing the intake 24h. The position of this fan 46 corresponds to the position through which the linear horizontal airflow from the intake 24h to the exhaust passage 24d passes. In other words, the fan 46 is positioned to promote the linear horizontal airflow from the intake 24h to the exhaust passage 24d.

[0266] The fan 46 draws in air that has flowed into the center battery case 24 through the intake 24h and discharges it to the upper part of the communication passage 24g and the rear end of the exhaust passage 24d, thereby generating a forward airflow from the intake 24h to the exhaust passage 24d. As a result, the cooling air from the intake 24h merges with the flow of cooling air from the cooling air passage 24c and is guided to the cooling air outlet 24b.

[0267] In the first embodiment, the outlet end of the return duct 43 was connected to the air conditioning case 40, and it was therefore preferable to have an air conditioning case 40 that houses the air conditioning unit 51, but 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 conditioning case 40, and various variations can be considered regarding the relative positions of the center battery case 24 and the air conditioning unit 51.

[0268] 17 , the air conditioning case 40 separate from the center battery case 24 may be eliminated, and an air conditioning unit 51 may be provided inside the center battery case 24. In this case, there is no cooling air outlet 24b for discharging air that has passed through the exhaust passage 24d from the center battery case 24 to the outside, and the air that has passed through the exhaust passage 24d is taken in by an air intake 51a of the air conditioning unit 51 inside the center battery case 24.

[0269] 18, the air conditioning unit 51 may be disposed outside the center battery case 24, the air conditioning case 40 may be omitted, and the air intake 51a of the air conditioning unit 51 may be directed toward 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 intake 51a of the air conditioning unit 51.

[0270] The center battery case 24 illustrated in Figures 10, 15, 17, and 18 described above is configured so that, in addition to the cooling air passage 24c for directing cooling air onto the center battery 50, which is the equipment to be cooled, an exhaust air passage 24d is provided inside for discharging the cooling air after cooling the center battery 50.

[0271] This center battery case 24 may be replaced with a center battery case 24 that does not have the exhaust passage 24d (or the partition plate 24e that forms the exhaust passage 24d), as shown in FIG. 19, for example.

[0272] An air-cooling system according to a third embodiment having a center battery case 24 shown in FIG. 19 and an air-cooling duct structure shown in FIG. 20 will now be described.

[0273] That is, the center battery case 24 in FIG. 19 has a cooling air inlet 24a at the front end that is connected to the discharge manifold 41a, and a cooling air outlet 24b at the rear end of the center battery case 24.

[0274] The center battery case 24 does not have any passages, such as the exhaust air passage 24d, that allow the cooling air to flow in a different direction from the cooling air that enters through the cooling air inlet 24a and flows rearward. Instead, the air that flows into the center battery case 24 through the cooling air inlet 24a at the front end of the center battery case 24 flows entirely rearward throughout almost the entire interior of the center battery case 24 and is discharged from the cooling air outlet 24b at the rear end of the center battery case 24.

[0275] A return duct 44 is provided outside the center battery case 24 to return the cooling air that has cooled the center battery 50 inside the center battery case 24 to the air intake port 51 a of the air conditioning unit 51 .

[0276] 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 over the upper part of the vehicle body 2 above the center battery case 24 so as to extend in the front-to-rear direction. That is, as shown in Figure 20, the return duct 44 has an extension 44a that extends in the front-to-rear direction parallel to the extensions 42a, 43a of the ducts 42, 43 from the front of the vehicle body 2 to a midpoint in the front-to-rear direction corresponding to the rear end of the center battery case 24.

[0277] When the center battery case 24 and return duct 44 shown in Figures 19 and 20 are applied to the first embodiment, for example, which has return ducts 43L, 43R extending to the air conditioning case 40 that houses the air conditioning unit 51, it is preferable to position the extension portion 44a of the return duct 44 between the left return duct 43L and the right return duct 43R on the vehicle center frame 21.

[0278] In addition, the front end of the return duct 44 from the center battery case 24 is connected to the upper end of the air conditioner case 40, similar to the front ends of the return ducts 43L, 43R from the side battery case 36, and is configured to exhaust air into the space within the air conditioner case 40.

[0279] Alternatively, as shown in Figure 19, an intake manifold 51b communicating with the air intake port 51a may be provided in the front of the air conditioning unit 51, and the front ends (outlet ends) of the return ducts 43L, 43R, and 44 may be connected to the intake manifold 51b.

[0280] Furthermore, as shown in Figure 20, it is preferable to provide an expansion / contraction section 44c between the front end of the return duct 44 and the front end of the extension section 44a on the vehicle body center frame 21, which is capable of expanding and contracting in response to the forward and backward movement of the center battery case 24, similar to the expansion / contraction section 43c of the return duct 43.

[0281] That is, in the third embodiment, the vehicle body 2 is provided with a center battery 50 that is cooled by cooling air from an air conditioning unit 51 (cooling device) in addition to the side battery 37, and at least one duct 44 extending from the air conditioning unit 51 (cooling device) to the center battery 50 has an extension portion (first extension portion) 44a that extends in the fore-and-aft direction (first direction) in the range from the front end (first end) of the vehicle body 2 to the fore-and-aft midpoint (midpoint).

[0282] In the work vehicle 1, various circuit structures may be applied to supply the temperature adjustment medium discharged from the temperature adjustment device to the equipment to be temperature adjusted.

[0283] The temperature adjustment device may be an air conditioning unit (air temperature adjustment device) 51 as the air cooling device 110 (see FIG. 14) or a radiator 52 as the water cooling device 120 (see FIG. 14), or may be a heater, etc. The temperature adjustment medium may be air, water, a refrigerant gas, etc.

[0284] Possible temperature adjustment target equipment includes batteries such as the aforementioned center battery 50 and side battery 37, electrical equipment such as the aforementioned working system electric unit E1, hydraulic system electric unit E2, and 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.

[0285] When a battery is a device to be temperature-regulated, the medium for temperature regulation may be air as cooling wind, and the battery may be cooled by an air-cooling device 110 such as an air conditioning unit 51. The battery may also be cooled by coolant generated by the heat exchange action of a radiator 52, which is a water-cooling device 120.

[0286] When electrical equipment such as an electric motor or inverter is the equipment to be temperature-adjusted, cooling water can be considered as a medium for temperature adjustment, and it is possible to cool the equipment using cooling water generated by a radiator 52 as a water-cooling device 120.

[0287] Furthermore, when hydraulic equipment such as a hydraulic pump 57 or various hydraulic actuators is the equipment to be temperature-regulated, it is conceivable to form fins or the like on the case that houses such hydraulic equipment and cool the case with cooling air from the air conditioning unit 51 as the air-cooling device 110, or to form a water jacket on the case and send cooling water from the radiator 52 as the water-cooling device 120 into the water jacket to cool the case.

[0288] Alternatively, it is also possible to use, for example, an air conditioning unit 51 as an air-cooling device or a radiator 52 as a water-cooling device as an oil cooler that cools the hydraulic oil supplied to hydraulic pump 57 and hydraulic actuators, and the lubricating oil supplied to each part of work vehicle 1. Alternatively, a temperature adjustment device as an oil cooler may be provided separately from air conditioning unit 51 and radiator 52.

[0289] In addition, when a heater is used as a temperature control device, the temperature control medium may be hot water heated by the heater, and for example, if the work vehicle 1 is used in a low-temperature area where the lubricating efficiency of lubricating oil, etc. is reduced, the hot water may be circulated within the work vehicle 1 to warm the lubricating oil.

[0290] Furthermore, when the vehicle structure consists of a vehicle body 2 and left and right running structures 3L, 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 for the structure of the temperature adjustment system for supplying the temperature adjustment medium generated by the temperature adjustment device to the temperature adjustment target equipment D1, D2L, D2R provided on the vehicle body 2, the left running structure 3L, and the right running structure 3R, respectively.

[0291] 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, 3R provided on the left and right sides of the vehicle body 2. A first device D1 and a first adjustment device T1 that adjusts the temperature of the first device D1 are arranged in the vehicle body 2, a second device D2L (or D2R) and a second adjustment device T2L (or T2R) that adjusts the temperature of the second device D2L (or D2R) are arranged in one of the left and right traveling structures 3L, 3R, and a third device D2R (or D2L) and a third adjustment device T2R (or T2L) that adjusts the temperature of the third device D2R (or D2L) are arranged in the other of the left and right traveling structures 3L, 3R.

[0292] In other words, the temperature control system TS1 is an independent temperature control system in which the vehicle body 2, left running structure 3L, and right running structure 3R each have their own independent temperature control devices T1, T2L, and T2R, and their own independent temperature control circuits C1, C2L, and C2R as closed circuits.

[0293] The first device D1, the second device D2L (or D2R), and the third device D2R (or D2L) to be temperature-controlled in this stand-alone temperature control system TS1 may be various and are not limited to a single device.

[0294] For example, the first device D1 is a working 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 which is a hydraulic device for controlling a hydraulic actuator equipped on the vehicle body 2. The first device D1 may also include a hydraulic electric unit E2 (inverter 55 and electric motor 56) for driving the hydraulic pump 57.

[0295] Also, for example, the second device D2L (or D2R) and the third device D2R (or D2L) are each a traveling motor 7 (7F, 7R) that drives the wheels 5 (front wheels 5F, rear wheels 5R) of the traveling structures 3L, 3R.

[0296] Furthermore, various types of the first adjustment device T1, the second adjustment device T2L (or T2R), and the third adjustment device T2R (or T2L) in this stand-alone temperature adjustment system TS1 are possible, and there are no limitations on the device structure. Note that it is preferable that the devices correspond to the first device D1, the second device D2L (or D2R), and the third device D2R (or D2L), which are the temperature adjustment targets, respectively.

[0297] 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, etc.

[0298] Furthermore, the first adjusting device T1, the second adjusting device T2L (or T2R), and the third adjusting device T2R (or T2R) may be provided at any position on the vehicle body 2 and the left and right running structures 3L, 3R.

[0299] In addition, in a work vehicle 1 that employs an independent temperature control system TS1, the vehicle body 2 is provided with a first adjustment circuit C1 that circulates a temperature control medium between the first adjustment device T1 and the first equipment D1, one of the running structures 3L (or 3R) is provided with a second adjustment circuit C2L (or C2R) that circulates a temperature control medium between the second adjustment device T2L (or T2R) and the second equipment D2L (or D2R), and the other running structure 3R (or 3L) is provided with a third adjustment circuit C2R (or C2L) that circulates a temperature control medium between the third adjustment device T2R (or T2L) and the third equipment D2R (or D2L).

[0300] Various types of the first adjustment circuit C1, the second adjustment circuit C2L (or C2R), and the third adjustment circuit C2R (or C2L) are possible, and there are no limitations on the device structure. It is preferable that the devices correspond to the first device D1, the second device D2L (or D2R), and the third device D2R (or D2L), which are the targets of temperature adjustment, respectively.

[0301] 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) may include 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 tank for storing coolant and a pump for discharging coolant.

[0302] In the work vehicle 1 described above, the water-cooled cooling (temperature adjustment) system shown in FIG. 12 is made up of a water-cooled cooling (temperature adjustment) circuit R1 for cooling the working electric unit E1 and a water-cooled cooling (temperature adjustment) circuit R2 for cooling the hydraulic electric unit E2 inside the vehicle body 2, and a water-cooled cooling (temperature adjustment) circuit R3F for cooling the front traveling electric unit E3F and a water-cooled cooling (temperature adjustment) circuit R3R for cooling the rear traveling electric unit E3R, which are provided for each traveling structure 3. This water-cooled cooling (temperature adjustment) system is one example of an application of the independent temperature adjustment system TS1.

[0303] In the embodiment equipped with the water-cooled cooling (temperature adjustment) circuits R1, R2, R3L, R3R shown in Figures 12 and 13 described above, the first device D1 is a working system electric unit E1 and / or a hydraulic pump 57, etc., and the second device D2L (or D2R) and the third device D2R (or D2L) are travel motors 7 (7F, 7R), and accordingly, the first adjustment device T1, the second adjustment device T2L (or T2R), and the third adjustment device T2R (or T2L) are all radiators (radiators 52, 71).

[0304] The first adjustment device T1 includes a radiator 52 and a radiator fan 52a, the second adjustment device T2L (or T2R) and the third adjustment device T2R (or T2L) each include a radiator 71 and a radiator fan 71a, the first adjustment circuit C1 includes a reservoir (for storing coolant) tank 59 and an electric coolant (for discharging coolant) pump 58, and the second adjustment circuit C2L (or C2R) and the third adjustment circuit C2R (or C2L) each include a reservoir (for storing coolant) tank 73 and an electric coolant (for discharging coolant) pump 72.

[0305] As shown in Figures 1 to 6, the left and right running structures 3L and 3R each have wheels 5, and the second adjustment device T2L (or T2R) and the third adjustment device T2R (or T2L) are each arranged to face the contact surfaces of the wheels 5 of the running structures 3L and 3R.

[0306] Furthermore, the second adjusting device T2L (or T2R) and the third adjusting device T2R (or T2L) are radiators 71, and are each inclined with respect to the front-to-rear direction in front of the wheel 5 (front wheel 5F).

[0307] Note that Figure 21 shows an example of application of the independent temperature adjustment system TS1 in which a radiator 52 and a radiator fan 52a are applied to the temperature adjustment device T1 in the vehicle body 2, an electric motor 54 etc. as the working electric unit E1 and an electric motor 56 etc. as the hydraulic electric unit E2 are applied to the temperature adjustment target equipment D1, a water-cooled cooling (temperature adjustment) circuit R1 is applied to the temperature adjustment circuit C1, a radiator 71 and a radiator fan 71a are applied to the temperature adjustment devices T2L, T2R in the left and right running structures 3L, 3R, traveling electric units E3 (E3FL, E3FR, E3RL, E3RR), i.e., a front traveling motor 7F and a rear traveling motor 7R etc., are applied to the temperature adjustment target equipment D2L, D2R, and water-cooled cooling (temperature adjustment) circuits R2L, R2R are applied to the temperature adjustment circuits C2L, C2R.

[0308] The temperature adjustment system TS2 shown in Figure 22 has a temperature adjustment device T3 provided in either the vehicle body 2, the left running structure 3L, or the right running structure 3R (in this embodiment, it is provided in the vehicle body 2, but it may be provided in either), and a temperature adjustment circuit C3 for supplying temperature adjustment medium from the temperature adjustment device T3 to temperature adjustment target devices D1, D2L, and D2R provided in the vehicle body 2, the left running structure 3L, and the right running structure 3R.

[0309] The temperature adjustment circuit C3 has branch circuits that branch out to the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R. Within the vehicle body 2, a branch temperature adjustment circuit C3a is provided for supplying temperature adjustment medium from the temperature adjustment device T3 to the temperature adjustment target device D1 provided in the vehicle body 2, within the left traveling structure 3L, a branch temperature adjustment circuit C3b is provided for supplying temperature adjustment medium from the temperature adjustment device T3 to the temperature adjustment target device D2L provided in the left traveling structure 3L, and within the right traveling structure 3R, a branch temperature adjustment circuit C3c is provided for supplying temperature adjustment medium from the temperature adjustment device T3 to the temperature adjustment target device D2R provided in the right traveling structure 3R.

[0310] The cooling medium (similar to the temperature adjustment system TS1, various types are possible) discharged from the temperature adjustment device T3 passes through a common medium supply passage C3d, then branches off to branch temperature adjustment circuits C3a, C3b, and C3c, and as it circulates around each branch temperature adjustment circuit C3a, C3b, and C3c, it cools each of the temperature adjustment target devices D1, D2L, and D2R (sequentially if there are multiple devices), and eventually returns to the junction with the common medium return passage C3e, and the joined medium passes through the medium return passage C3e and is returned to the temperature adjustment device T3, where it is again subjected to temperature adjustment.

[0311] In other words, the temperature control system TS2 is a branched temperature control system that has a temperature control circuit C3 that consists of branch temperature control circuits C3a, C3b, and C3c branching from a single temperature control device T3 to the temperature control target devices D1, D2L, and D2R that are provided in the vehicle body 2, the left running structure 3L, and the right running structure 3R, respectively.

[0312] The temperature adjustment circuit C3 in the temperature adjustment system TS2 in Figure 22 is structured so that it branches into branch temperature adjustment circuits C3a, C3b, and C3c after passing through a common medium supply passage C3d extending from the outlet of the temperature adjustment device T3, but this is not limited to this, and it may also be structured so that it branches into branch temperature adjustment circuits C3a, C3b, and C3c immediately from the outlet of the temperature adjustment device T3.

[0313] Also, in Figure 22, the position where the temperature control circuit C3 branches off from the common medium supply passage C3d into the branch temperature control circuits C3a, C3b, and C3c is the rear of the vehicle body 2, but this is not limited to this, and the branch temperature control circuits C3a, C3b, and C3c may be branched off from the common medium supply passage C3d at any position on the work vehicle 1.

[0314] Furthermore, the temperature adjustment circuit C3 in the temperature adjustment system TS2 of Figure 22 is configured so that the medium that has circulated through the branch temperature adjustment circuits C3a, C3b, and C3c is collected (merged) in a common medium return passage C3e extending from the intake port of the temperature adjustment device T3, and then returned to the intake port of the temperature adjustment device T3, but this is not limited to this, and the medium outlet of each branch temperature adjustment circuit C3a, C3b, and C3c may be directly connected to the intake port of the temperature adjustment device T3.

[0315] Also, in Figure 22, the location where the temperature control circuit C3 collects the cooling (temperature control) medium circulating through the branch temperature control circuits C3a, C3b, and C3c and merges it into a common medium return passage C3e is the rear of the vehicle body 2, but this is not limited to this, and the branch temperature control circuits C3a, C3b, and C3c may be merged into the common cooling (temperature control) medium return passage C3e at any location on the work vehicle 1.

[0316] 22 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 one of the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R, temperature-adjusted devices D1, D2L, and D2R that are temperature-adjusted by the temperature adjustment device T3 and include 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, and a temperature adjustment circuit C3 that sends a temperature-adjusted medium from the temperature adjustment device T3 to the temperature-adjusted devices D1, D2L, and D2R. The temperature adjustment circuit C3 branches off from the temperature adjustment device T3 and is connected to the first device D1, the second device D2L, and the third device D2R, respectively.

[0317] The first device D1, the second device D2L (or D2R), and the third device D2R (or D2L) to be temperature-controlled in this branch-type temperature control system TS2 may be various and are not limited to a single device.

[0318] For example, in the work vehicle 1 shown in Figures 1 to 14, 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 may be considered as the first equipment 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 traveling motor 7R) may be considered as the second equipment D2L and / or D2R.

[0319] The adjusting device T3 in this branch-type temperature adjustment system TS2 may be of various types and is not limited in structure, but is preferably a device compatible with the first device D1, the second device D2L (or D2R), and the third device D2R (or D2L), which are temperature adjustment target devices.

[0320] For example, if at least one of the first device D1, the second device D2L (or D2R), and the third device D2R (or D2L) as the devices to be cooled is a battery, the adjustment device T3 may be an air temperature adjustment device, and the battery may be cooled by the cooling air discharged from it, or the adjustment device T3 may be a radiator and a radiator fan, and the battery may be cooled by the cooling water generated by the heat exchange between the radiator and the radiator fan.

[0321] In addition, when a water-cooled branched temperature control system TS2 is constructed in a work vehicle 1 with the adjustment device T3 as a radiator and radiator fan, the radiator as the adjustment device T3 may be the radiator 52 and radiator fan 52a of the vehicle body 2, or may be the radiator 71 and radiator fan 71a provided in either the left running structure 3L or the right running structure 3R.

[0322] Furthermore, the positions of the radiator and radiator fan as the adjustment device T3 are not limited to the positions of the radiators 52, 71 and radiator fans 52a, 71a as shown in Figures 1 to 9, etc., but may be other positions suitable for circulating cooling water between the first device D1, the second device D2L (or D2R), and the third device D2R (or D2L).

[0323] Furthermore, the capacity (size) of the radiator serving as the adjustment device T3 is not limited and may be larger than those of the adjustment devices T1, T2L, and T2R in the independent temperature adjustment system TS1, taking into consideration the supply of cooling water to the first device D1, the second device D2L (or D2R), and the third device D2R (or D2L).

[0324] In addition, the temperature adjustment circuit C3 in the branched temperature adjustment system TS2 includes a first temperature adjustment circuit C3a that circulates a temperature adjustment medium between the temperature adjustment device T3 and the first device D1, a second temperature adjustment circuit C3b that circulates a 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 a temperature adjustment medium between the temperature adjustment device T3 and the third device D2R (or D2L).

[0325] As described above, when the branched temperature adjustment system TS2 applied to the work vehicle 1 is a water-cooled system with the adjustment device T3 as a radiator, it is preferable that the first temperature adjustment circuit C3a, which supplies cooling water to the work system electric unit E1 (electric motor 54, etc.) and the hydraulic system electric unit E2 (electric motor 56, etc.) as the first equipment D1, be provided with a pair of cooling water discharge pumps 58 for discharging cooling water to each of the work system electric unit E1 (electric motor 54, etc.) and the hydraulic system electric unit E2 (electric motor 56, etc.), and at least one cooling water storage (reservoir) tank 59.

[0326] In this case, it is preferable that each of the second and third devices D2L and D2R, for example, 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 (front traveling motor 7F, etc.) and the rear traveling system electric unit E3R (rear traveling motor 7R, etc.), be provided with a pair of cooling water discharge pumps 72 for discharging cooling water to the front traveling system electric unit E3F (front traveling motor 7F, etc.) and the rear traveling system electric unit E3R (rear traveling motor 7R, etc.), respectively, and at least one cooling water storage (reservoir) tank 73.

[0327] In addition, an air-cooled cooling (temperature control) system in the aforementioned work vehicle 1 that supplies cooling air from a single air conditioning unit 51 to the center battery 50 in the vehicle body 2 and to the side batteries 37 provided on each of the left and right running structures 3 is one example of an application of the branch-type temperature control system TS2.

[0328] In the air-cooling system according to the first embodiment described above, the cooling air passage 24c and the exhaust air passage 24d within the center battery case 24 shown in FIG. 10 correspond to the first temperature adjustment circuit C3a that circulates air between the air conditioning 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 correspond to the second temperature adjustment circuit C3b (or the third temperature adjustment circuit C3c) that circulates air between the air conditioning unit 51 and the left side battery case 36L that is the second device D2L, and 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 conditioning unit 51 and the right side battery case 36R that is the third device D2R.

[0329] In the air-cooled system according to the first embodiment, the air outlet (discharge manifolds 41a, 41b) of the air conditioning unit 51 immediately branches into the cooling air passage 24c, the left outgoing duct 42L, and the right outgoing duct 42R, which correspond to the passage portions to the first to third devices of the first to third temperature adjustment circuits C3a, C3b, and C3c, respectively, and the exhaust air passage 24d, the left return duct 43L, and the right return duct 43R, which correspond to the passage portions from the first to third devices of the first to third temperature adjustment circuits C3a, C3b, and C3c, respectively, remain separate from each other (do not merge), and their terminal ends are directly connected to the air conditioning unit 51 (or the air conditioning case 40 that houses it).

[0330] However, even in the air-cooling system of the first embodiment, common medium paths (merging paths) C3d and C3e, which are paths that combine the temperature adjustment circuits C3a, C3b, and C3c, which are branch circuits, may be provided, as shown in Fig. 22. Furthermore, with regard to the integration (merging) of such medium paths, it is not necessary to combine all three temperature adjustment circuits C3a, C3b, and C3d, and only two of them may be combined.

[0331] For example, the outgoing ducts 42L, 42R shown in Figure 2 etc. (corresponding to the passage portions leading 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 outgoing duct so as to correspond to a common cooling (temperature adjustment) medium passage (junction passage) C3d in the range from the air conditioning 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 point where it bends to the second extension portion 42b).

[0332] In addition, the return ducts 43L and 43R shown in Figure 2 etc. (corresponding to the passage portion of the medium after passing through the second device and the third device in the second temperature control circuit C3b and the third temperature control 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 conditioning unit 51 (air intake port 51a) to the rear end of the first extension section 43a (the point where it bends to the extension section 43b).

[0333] In addition, in the air-cooled system of the second embodiment shown in Figures 15 and 16, the exhaust passage 24d in the center battery case 24 is a passage that integrates a connecting passage 24g corresponding to the passage after passing through the first device D1 of the first temperature adjustment circuit C3a, and return ducts 43L, 43R corresponding to the passage 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, and corresponds to the medium return passage D3e shown in Figure 22.

[0334] As mentioned above, the exhaust air passage 24d may be divided into an air passage from the intake 24h and an air passage from the cooling air passage 24c. In this case, the first temperature adjustment circuit C3a consisting of the cooling air passage 24c and the connecting passage 24g is provided up to the air intake 51a of the air conditioning unit 51 while remaining separate from the second temperature adjustment circuit C3b and the third temperature adjustment circuit C3c, while the passages after passing through the second equipment D2L (or D2R) and the third equipment D2R (or D2L), which are the return ducts 43L, 43R, are integrated (merged) into the passage portion of the divided exhaust air passage 24d that is connected to the intake 24h.

[0335] The temperature adjustment system TS3 shown in Figure 23 is provided with a temperature adjustment device T4 in either the vehicle body 2, the left running structure 3L, or the right running structure 3R (in this embodiment, it is provided in the vehicle body 2, but it may be provided in either), and the temperature adjustment medium from the temperature adjustment device T4 circulates through the temperature adjustment target equipment D1 of the vehicle body 2, the temperature adjustment target equipment D2L of the left running structure 3L, and the temperature adjustment target equipment D2R of the right running structure 3R in sequence (in this embodiment, the order is temperature adjustment target equipment D2R of the right running structure 3R, temperature adjustment target equipment D1 of the vehicle body 2, and temperature adjustment target equipment D2L of the left running structure 3L, but any order is acceptable), forming a temperature adjustment circuit C4 which is a single circulation circuit that connects the temperature adjustment target equipment D1, D2L, and D2R in series throughout the entire work vehicle 1.

[0336] 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) using 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 satellites, and detects the position of the vehicle body 2 (for example, latitude and longitude) based on the satellite signals.

[0337] The positioning device 11 has a receiving device 12 and an inertial measurement unit (IMU) 13. The receiving device 12 has an antenna and the like and is a device that receives satellite signals transmitted from positioning satellites, and is attached to the vehicle body 2. The inertial measurement unit 13 has 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 be detected by installing multiple positioning devices 11.

[0338] 14 , the work vehicle 1 is equipped with a communication device 14. The communication device 14 includes a communication circuit for communicating via an on-board network and a wireless communication circuit for wireless communication. The wireless communication circuit can communicate directly or indirectly wirelessly with external devices using communication standards such as IEEE 802.11 series Wi-Fi (Wireless Fidelity, registered trademark), BLE (Bluetooth (registered trademark) Low Energy), LPWA (Low Power Wide Area), and LPWAN (Low-Power Wide-Area Network).

[0339] As another example, the communication device 14 may be provided with a communication circuit capable of wirelessly communicating with an external device via, for example, a mobile phone communication network or a data communication network. The external device may be, for example, a personal computer, a smartphone, a tablet computer, a PDA, or a server.

[0340] As shown in Figures 1 to 6, the work vehicle 1 is equipped with at least one situation detection device 10 that detects the situation around the work vehicle 1 so that, for example, the work vehicle 1 can start moving only after checking that the surroundings are safe.

[0341] The situation detection device 10 includes a camera (image capture device) 10a, a sensor 10b, and a calculation unit 10c (see FIG. 14). In this embodiment, the situation detection device 10 includes both the camera 10a and the sensor 10b, but may include only one of them.

[0342] The camera 10a is configured by 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.

[0343] Camera 10a captures images of the surroundings of work vehicle 1 and generates image signals. Calculation unit 10c is made up of a computer or the like that includes a signal processing circuit that processes the generated image signals. The signal processing circuit detects the state of the object (presence or absence of the object, the position of the object, the type of object, the size of the object, etc.) based on the image signals output from camera 10a.

[0344] The sensor 10b is an optical sensor, and is configured, for example, by a LiDAR (Light Detection And Ranging) sensor.

[0345] A LIDAR (laser sensor) emits pulsed measurement light (laser light) millions of times per second from a light source such as a laser diode, and scans the measurement light horizontally or vertically by reflecting it off a rotating mirror, projecting it onto a predetermined detection range (sensing range).

[0346] The LIDAR then receives the measurement light reflected by the object with a light receiving element. The signal processing circuit of the calculation unit 10c detects the state of the object (presence / absence of the object, position of the object, type of the object, size of the object, etc.) based on the light receiving signal output from the LIDAR light receiving element.

[0347] The signal processing circuit detects the distance to the target based on the time from when the LIDAR emits the measurement light to when it receives the reflected light (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.

[0348] As described above, the optical sensor 10b may be supplemented with, for example, an acoustic sensor to enhance detection accuracy.

[0349] The ultrasonic sensor is, for example, composed of an airborne ultrasonic sensor such as a sonar. The airborne ultrasonic sensor transmits measurement waves (ultrasound waves) within a predetermined detection range using a transmitter, and receives the reflected waves from an object using a receiver. A signal processing circuit detects the state of the object (presence or absence of the object, its position, type, size, etc.) based on the signal output from the receiver.

[0350] The signal processing circuit detects the distance to the target based on the time from when the airborne ultrasonic sensor emits a measurement wave until when it receives the reflected wave (TOF (Time of Flight) method). Note that the method for detecting distance using an ultrasonic sensor may be a method other than the TOF method.

[0351] 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). As the situation around the work vehicle 1, the situation detection device 10 detects obstacle information indicating whether there are any obstacles or people in the vicinity of the work vehicle 1 that may come into contact with the work vehicle 1.

[0352] The situation detection device 10 detects road information, which is information about roads on which the left and right traveling structures 3 can travel, as the situation around the work vehicle 1. More specifically, it detects road information, which is a value related to the road on which the traveling structures 3 can travel. The situation detection device 10 detects, for example, the width of the traveling road as the road information.

[0353] The width of the travel path detected by the situation detection device 10 is the width of an object that the work vehicle 1 is attempting to straddle between the left traveling structure 3L and the right traveling structure 3R. The situation detection device 10 detects, as the width of the travel path, for example, the width of a ridge on the ground or the width of an obstacle on the ground that obstructs travel.

[0354] Furthermore, the situation detection device 10 detects, for example, the height of the road as road information. The height of the road detected by the situation detection device 10 is the height of an object that the vehicle body 2 is attempting to cross between the left traveling structure 3L and the right traveling structure 3R. The situation detection device 10 detects, for example, the height of ridges on the ground, the height of obstacles on the ground that obstruct traveling, etc. as the height of the road.

[0355] Examples of obstacles that impede travel include grooves or holes formed in 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 crops planted on the ground as the height of the obstacle.

[0356] The height of the crop detected by the situation detection device 10 is the height from the ground where the wheels 5 of the traveling structure 3 touch the ground to the top of the crop. For example, if the crop is planted in ridges, the wheels 5 of the traveling structure 3 touch the ground between the ridges rather than on the ridges, and therefore the height of the crop detected by the situation detection device 10 is "the height of the crop itself + the height of the ridges."

[0357] The situation detection device 10 may detect the inclination of the ground in the left-right direction 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. For this reason, the situation detection device 10 may be mounted on each of the left traveling frame 30L and the right traveling frame 30R.

[0358] In this case, for example, an inclination sensor that detects the inclination of the work vehicle 1 (vehicle body 2) in the left-right direction can be used as the situation detection device 10. Alternatively, a camera 10a can be used as the situation detection device 10, and the calculation unit 10c can be configured to detect the inclination of the ground in the left-right direction based on an image captured by the camera 10a.

[0359] Furthermore, the work vehicle 1 is equipped with a detection device that detects the state of the work vehicle 1 itself in addition to the situation detection device 10 that detects the situation around the work vehicle 1 .

[0360] 14 shows, as detection devices for detecting the state of the work vehicle 1 itself, a distance detection device 16 that detects the left-right distance between the left traveling structure 3L and the right traveling structure 3R, which corresponds 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 contact points of the wheels 5 to the lowest part of the vehicle body 2. In addition, it is conceivable that the work vehicle 1 may be equipped with 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 wheels 5, etc.

[0361] 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 a calculation unit (CPU, etc.) and a storage unit (RAM, ROM, etc.). The storage unit may include an external memory provided outside the control device 15. The control device 15 is connected to the various devices and mechanisms shown in Fig. 14 via an in-vehicle LAN (on-board network) such as a CAN (Controller Area Network) or a communication line.

[0362] The control device 15 controls the operations of various devices and mechanisms communicably connected to the control device 15 by the calculation unit executing various control programs stored in the storage unit.

[0363] 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, and the functions of these control units are realized by the calculation unit executing a predetermined control program stored in the memory unit.

[0364] 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-type automatic driving control.

[0365] In line-type automatic driving control, the automatic driving control unit 15A controls the output control inverter 6 of the travel motor 7 of each wheel unit 4 to control the rotation speed of the corresponding wheel 5 so that the work vehicle 1 (car body 2) moves along a predetermined planned driving line, and also 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.

[0366] In autonomous automatic driving control, the automatic driving control unit 15A sets the direction of travel (steering direction) and vehicle speed (velocity) of the vehicle body 2 based on the results of detection of the position of the work vehicle 1 (vehicle body 2) by the positioning device 11, and controls the output control inverter 6 of the driving motor 7 of each wheel unit 4 to control the rotation speed of the corresponding wheel 5 so that the set steering angle (direction) and vehicle speed are achieved, and also controls the control valve unit 27 (control valve) 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.

[0367] Note that the line-type automatic driving control and the autonomous-type automatic driving control may be switchable using a switch or the like. Also, the automatic driving control unit 15A may be configured to be able to execute either the line-type automatic driving control or the autonomous-type automatic driving control. Note that the configuration of the automatic driving control unit 15A is not limited to the configuration described above.

[0368] Furthermore, the automatic driving control unit 15A determines, based on obstacle information obtained by sensing (detecting objects) the surroundings of the work vehicle 1 using the situation detection device 10, whether or not to start the work vehicle 1 that is stopped, whether or not to stop the work vehicle 1 that is moving, whether or not to steer to change the direction of travel, whether or not to stop the drive of the work equipment that is working, and / or whether or not to raise the work equipment, etc., and controls the output control inverter 6 and steering cylinder 35 of the travel motor 7 in the traveling structure 3, the output control inverter 53 of the electric motor 54 in the work system electric unit E1, the output control inverter 55 of the electric motor 56 in the hydraulic system electric unit E2, etc. to realize the determined state.

[0369] As described above, the work vehicle 1 can perform automatic driving (unmanned driving) without an operator on board because the control device 15 includes the automatic driving control unit 15A. Therefore, the work vehicle 1 in the illustrated embodiment does not have a driver's seat where an operator sits.

[0370] However, the work vehicle 1 may be a vehicle that an operator rides in and that performs automatic driving. Alternatively, the work vehicle 1 may be a vehicle that an operator rides in and drives to perform driving. When the work vehicle 1 is a vehicle that an operator rides in, the vehicle body 2 is provided with a driver's seat.

[0371] The distance change control unit 15B of the control device 15 controls the control valve unit 27 (control valve) for controlling the extension and contraction of the width change cylinder 8A and / or width change cylinder 8B as a body deformation device based on information regarding the width of the running path contained in the road information obtained by detection by the situation detection device 10, information regarding the distance between the left running structure 3L and the right running structure 3R detected by the distance detection device 16, etc., so that the distance between the left running structure 3L and the right running structure 3R corresponds to the detected width of the running path, i.e., so that the left and right wheels 5 are correctly positioned between the furrows.

[0372] The height change control section 15C of the control device 15 controls the control valve unit 27 (control valve) for controlling the extension and contraction of the body lifting cylinder 9 as a body moving device based on information regarding the height of the driving path contained in the road information obtained by detection by the situation detection device 10 and information regarding the vehicle height detected by the vehicle height detection device 17, so that the vehicle height, which is the vertical distance from the contact point of the wheels 5 to the bottom end of the body 2, corresponds to the detected height of the driving path, i.e., so that the body 2 straddles crops, etc. growing on the driving path.

[0373] In addition, the height change control unit 15C of the control device 15 controls the control valve unit 27 (control valve) for controlling the extension and contraction of the left body lifting cylinder 9L and the right body lifting cylinder 9R as body moving devices, in order to adjust the difference in the piston rod extension amounts of the left body lifting cylinder 9L and the right body lifting cylinder 9R, so as to adjust the left and right tilt of the body 2, based on information regarding the left and right inclination of the ground obtained by detection by the situation detection device 10.

[0374] In addition, the position change control unit 15D of the control device 15 may measure the slip ratio of the front wheels 5F and rear wheels 5R, for example, from the detection results of a rotation speed detection device that detects the rotation speed of the wheels 5, and if the slip ratio of the front wheels 5F is high, for example, it may cause an external device to display a warning via the communication device 14 to move the center battery case 24 forward.

[0375] Furthermore, if the work vehicle 1 is equipped with a battery movement actuator 81 (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 movement actuator 81 to move the center battery case 24 (if the battery movement actuator 81 is a hydraulic actuator, it controls the corresponding control valve).

[0376] Furthermore, the work vehicle 1 is equipped with one or more temperature detection devices 18, and the control device 15 controls the output of the air-cooling (air-conditioning) device 110, such as the air conditioning unit 51, and the water-cooling device 120, such as the radiator fans 52a, 71a, based on the detection results of the temperature detection devices 18, thereby effectively cooling (adjusting the temperature) the center battery 50 and the left and right side batteries 37L, 37R, etc., which are to be cooled (temperature regulated), electrical equipment such as the work system electric unit E1, hydraulic system electric unit E2, and traveling system electric unit E3 (E3F, E3R), and hydraulic equipment such as the control valve unit 27.

[0377] The functions and effects of each of the components of the work vehicle 1 described above will be described below.

[0378] (Item A1) A vehicle includes a vehicle body 2, a cooling device (air conditioning unit 51) provided in the vehicle body 2, at least one device to be cooled (battery 37, 50) cooled by cooling air discharged from the cooling device (air conditioning unit 51), and a plurality of ducts 42, 43, 44 for circulating cooling air between the cooling device (air conditioning unit 51) and the device to be cooled, wherein the vehicle body 2 has a first end and a second end (front end and rear end) facing each other in a first direction (front-rear direction), and a middle portion (front-rear middle portion) between the first end and the second end in the first direction. , the cooling device (air conditioning unit 51) is provided at the first end (front end) of the vehicle body 2, and of the plurality of ducts 42, 43, 44, the ducts 42, 43 extending from the cooling device (air conditioning unit 51) to the equipment to be cooled have first extension portions 42a, 43a extending in the first direction (front-rear direction) in the range from the first end (front end) to the midway portion (front-rear midway portion), and have second extension portions 42b extending in a direction different from the first direction (front-rear direction) at the midway portion (front-rear midway portion).

[0379] With the above configuration, the ducts 42, 43 that branch out to the left and right running structures 3L, 3R are arranged in a state where they are converged at the first extension portions 42a, 43a, resulting in compact piping that looks good and also allows for ample space to be secured for the arrangement of equipment arranged in the surrounding area.

[0380] (Item A2) The work vehicle 1 according to Item A1, wherein the first extensions 42a, 43a are arranged on an upper portion of the vehicle body 2 (vehicle body frame structure 20).

[0381] With the above configuration, the first extensions 42a, 43a of the duct 42 can be piped together at the top of the car body 2, which is convenient for maintenance and also allows for ample space to be secured for arranging other equipment in the middle and lower parts of the car body 2.

[0382] (Item A3) The work vehicle 1 described in Item A1 or A2, wherein the plurality of ducts 42, 43, 44 include an outgoing duct 42 extending to the equipment to be cooled (battery 37) in order to supply cooling air discharged from the cooling device (air conditioning unit 51) to the equipment to be cooled (battery 37), and return ducts 43, 44 extending from the equipment to be cooled (battery 37, 50) in order to return the cooling air that has cooled the equipment to the cooling device (air conditioning unit 51), and at least the outgoing duct 42 of the outgoing duct 42 and the return ducts 43, 44 is a duct that has the first extension portion 42 a.

[0383] With the above-described configuration, the first extending portion 42a of the outward duct 42 is arranged in a converged state, thereby realizing compact piping.

[0384] (Item A4) The work vehicle 1 described in Item A3, wherein the return duct 43 has an extension portion 43b that extends in a direction different from the first direction (front-to-rear direction), and the extension portion is arranged parallel to the second extension portion 42b that extends in a direction different from the first direction (front-to-rear direction) of the outward duct 42.

[0385] With the above configuration, the extending portions of the outgoing duct 42 and the return duct 43 in a direction different from the first direction can be arranged in a compact and visually neat manner.

[0386] (Item A5) The work vehicle 1 described in Item A3 or A4, wherein the outward duct 42 is connected to a lower part of a housing (side battery case 36) that houses the equipment to be cooled (side battery 37), and the return duct 43 is connected to an upper part of the housing (side battery case 36).

[0387] With the above configuration, inside the housing (side battery case 36), the cooling air that flows in from the bottom of the housing connected to the outward duct 42 becomes hot enough to cool the equipment to be cooled (side battery 37), rises, and can be efficiently discharged to the return duct 43 connected to the top of the housing.

[0388] (Item A6) The work vehicle 1 according to item A5, wherein the equipment to be cooled is a battery (side battery) 37.

[0389] With the above configuration, the battery 37, which tends to become hot inside the work vehicle 1, can be effectively cooled.

[0390] (Item A7) The work vehicle 1 described in any one of Items A3 to A6, wherein the return duct 43 is a duct that extends from the cooling device (air conditioning unit 51) to the equipment to be cooled (battery 50) and has the first extension portion 43a that extends in the first direction (front-to-rear direction), and the first extension portion 42a of the outward duct 42 and the first extension portion 43a of the return duct 43 are arranged in parallel.

[0391] With the above configuration, the return duct 43 is extended all the way to the cooling device (air conditioning unit 51), but the first extension portion 43a is arranged parallel to the first extension portion 42a of the outward duct 42, thereby realizing a compact piping structure that also looks good.

[0392] (Item A8) The work vehicle 1 described in Item A7, wherein the vehicle body 2 is provided with a second cooling target device (center battery 50) that is cooled by cooling air from the cooling device (air conditioning unit 51) separate from the cooling target device (side battery 37), and at least one duct 44 extending from the cooling device (air conditioning unit 51) to the second cooling target device (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 (front end) of the vehicle body 2 to the midpoint (front-rear midpoint).

[0393] With the above configuration, the duct 44 connected to the second device to be cooled (battery 50) also has the first extension portion 44a, and can be secured in a state where it is converged together with the other ducts 42, 43.

[0394] (Item A9) The work vehicle 1 described in any of Items A3 to A6, wherein the vehicle body 2 is provided with a second cooling target device (battery 50) that is cooled by cooling air from the cooling device (air conditioning unit 51) separate from the cooling target device (battery 37), a housing (center battery case 24) that houses the second cooling target device (battery 50) has an exhaust air passage 24d formed therein for discharging the cooling air that has cooled 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 air passage 24d within the housing (center battery case 24).

[0395] With the above configuration, the return duct 43 for returning the cooling air to the cooling device (air conditioning unit 51) after cooling the second cooling target device (battery 50) can be shortened, and it is also possible to eliminate the first extension portion 43a, thereby ensuring ample space for arranging other devices, such as on the top of the vehicle body 2.

[0396] (Item A10) The work vehicle according to Item A9, wherein the second cooling target device is a battery (center battery) 50.

[0397] With the above configuration, the battery 50, which tends to become hot inside the work vehicle 1, can be effectively cooled.

[0398] (Item A11) The work vehicle 1 described in any one of items A1 to A10, which includes a left traveling structure 3L provided on the left side of the vehicle body 2 and a right traveling structure 3R provided on the right side of the vehicle body 2, and the cooled equipment (side battery 37) includes a left cooled equipment (left side battery 37L) arranged on the left traveling structure 3L and a right cooled equipment (right side battery 37R) arranged on the right traveling structure 3R.

[0399] With the above configuration, the structure of item A1 etc. can be applied to the duct structure for supplying cooling air from the cooling device (air conditioning unit 51) to the equipment to be cooled (side battery 37) arranged on both the left and right sides of the vehicle body 2.

[0400] (Item A12) The plurality of ducts 42, 43 include a left outgoing duct 42L extending to the left cooling target device (left battery 37L) and a right outgoing duct 42R extending to the right cooling target device (right battery 37R) in order to supply cooled air discharged from the cooling device (air conditioning unit 51) to the cooling target device (battery 37), and a left return duct 43L extending from the left cooling target device (left battery 37L) and a right return duct 43R extending from the right cooling target device (right battery 37R) in order to return the cooled air after cooling the cooling target device (battery 37) to the cooling device (air conditioning unit 51), and at least the left outgoing duct 42L and the right outgoing duct 42R extend from the cooling device (air conditioning unit 51) to the left cooling target device (left battery 37L) and the right cooling target device (right battery 37R), respectively. The left outgoing duct 42L and the right outgoing duct 42R are ducts each having the first extension portion 42a extending in the first direction (front-rear direction) in a range from the first end portion (front end portion) to the midway portion (front-rear midway portion), and the second extension portion 42b of the left outgoing duct 42L extending in a direction different from the first direction (front-rear direction) and the second extension portion 42b of the right outgoing duct 42R extending in a direction different from the first direction (front-rear direction) extend in opposite left and right directions 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 portion 43b that extends in a direction different from the first direction (front-to-back direction), and the extension portion 43b of the left return duct 43L that extends in a direction different from the first direction (front-to-back direction) and the extension portion 43b of the right return duct 43R that extends in a direction different from the first direction (front-to-back direction) extend in opposite left and right directions relative to the vehicle body 2.

[0401] With the above configuration, the outbound duct 42 and the inbound duct 43 that circulate cooling air between the left and right cooling target devices (batteries 37) located on both the left and right sides of the vehicle body 2 and the cooling device (air conditioning unit 51) can be piped compactly.

[0402] (Item A13) The work vehicle 1 according to any one of Items A1 to A12, wherein the first direction is a front-to-rear direction of the vehicle body 2, and the direction different from the first direction (front-to-rear direction) is a left-to-right direction of the vehicle body 2.

[0403] With the above configuration, the first extension portions 42a, 43a of the multiple ducts 42, 43 can be arranged in a concentrated state by extending in the fore-and-aft direction of the vehicle body 2, while by having extension portions 42b, 43b that extend in the left-and-right direction, the ducts can be piped and connected compactly to the equipment to be cooled (battery 37).

[0404] (Item A14) The work vehicle 1 according to Item A13, wherein the first end is a front end of the vehicle body 2.

[0405] With the above configuration, the cooling device (air conditioning unit) 51 is arranged at the front end of the vehicle body 2 where it is easy to take in outside air to generate cooling air, thereby increasing the efficiency of generating cooling air by the cooling device (air conditioning unit 51).

[0406] (Item B1) A work vehicle 1 including a cooling device (air conditioning unit 51), a first cooling target device (center battery 50) and a second cooling target device (side battery 37) that are cooled by cooling air discharged from the cooling device (air conditioning unit 51), a first cooling housing (center battery case 24) that houses the first cooling target device (center battery 50), and a second cooling housing (side battery case 36) that houses the second cooling target device (side battery 37), wherein an intake 24h is provided in the first cooling housing (center battery case 24) for taking in air that is discharged from the second cooling housing (side battery case 36) after cooling the second cooling target device (side battery 37).

[0407] With the above configuration, it is possible to shorten the return duct 43 for sending air from the second cooling housing (side battery case 36) after cooling the second cooling target equipment (side battery 37), which contributes to making the piping structure of ducts and the like in the work vehicle 1 more compact and improving the freedom of layout of equipment.

[0408] (Item B2) The work vehicle 1 described in Item B1, wherein a cooling air passage 24c for directing cooling air from the cooling device (air conditioning unit 51) toward the first cooling target device (center battery 50) and an exhaust air passage 24d for discharging the air that has cooled the first cooling target device (center battery 50) to the cooling device (air conditioning unit 51) are formed within the first cooling housing (center battery case 24), and the air from the second cooling housing (side battery case 36) that is introduced into the first cooling housing (center battery case 24) through the intake 24h is merged with the air in the exhaust air passage 24d.

[0409] With the above configuration, the exhaust routes for the air after cooling the first cooling target device (center battery 50) and the air after cooling the second cooling target device (side battery 37) are unified into the exhaust passage 24d, thereby contributing to a reduction in the number of pipes for exhausting the air.

[0410] (Item B3) The work vehicle 1 described in Item B2, in which a first air guide device (fan 45) that guides air from the cooling air passage 24c to the exhaust air passage 24d, and a second air guide device (fan 46) that guides air from the intake 24h to the exhaust air passage 24d are provided within the first cooling housing (center battery case 24).

[0411] With the above-described 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, which contributes to improving the cooling efficiency.

[0412] (Item B4) The work vehicle 1 described in Item B2 or B3, wherein a partition plate 24e is provided above the first cooling target device (center battery case 24) within the first cooling housing (center battery case 24), and the space below the partition plate 24e within 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.

[0413] With the above-described configuration, the partition plate 24e reliably forms the exhaust air passage 24d above the cooling air passage 24c.

[0414] (Item B5) The work vehicle 1 described in Item B4, in which a vertical communication passage 24g that connects the outlet of the cooling air passage 24c and the inlet of the exhaust air passage 24d is provided along an end of the partition plate 24e within the first cooling housing (center battery case 24), a first air guide device (fan 45) that guides air from the cooling air passage 24c to a lower part of the communication passage 24g is provided at the outlet of the cooling air passage 24c, and the intake 24h and a second air guide device (fan 46) that guides the air introduced from the intake 24h to the inlet of the exhaust air passage 24d are provided at an upper part of the communication passage 24g.

[0415] With the above-described configuration, the tendency of the warmed air after cooling to rise is utilized, and the cooled air can be smoothly guided to the exhaust air passage 24d formed above the cooling air passage 24c.

[0416] (Item B6) The work vehicle 1 according to any one of Items B3 to B5, wherein the first air guiding device and the second air guiding device are fans 45, 46.

[0417] With the above configuration, the air suction effect and air blowing effect of the fans 45, 46 can reliably realize air flow within the first cooling housing (center battery case 24).

[0418] (Item B7) The work vehicle 1 according to any one of Items B1 to B6, wherein at least one of the first cooling target device and the second cooling target device is a battery 37, 50.

[0419] With the above-described configuration, the batteries 37, 50, which require temperature management to enable the electrical equipment and the like to operate properly, can be reliably cooled even within the work vehicle 1.

[0420] (Item B8) The work vehicle 1 according to any one of Items B1 to B7, comprising a vehicle body 2 and a running structure 3 provided on the side of the vehicle body 2, wherein the cooling device (air conditioning unit 51) and the first cooling housing (center battery case 24) are disposed on the vehicle body 2, and the second cooling housing (side battery case 36) is disposed on the running structure 3.

[0421] With the above configuration, the effect of unifying the exhaust route as described above can also be achieved for the first cooling housing (center battery case 24) and the second cooling housing (side battery case 36) that are distributed between the vehicle body 2 and the running structure 3.

[0422] (Item C1) A work vehicle equipped with ducts 42, 43, 44 that can expand and contract in response to changes in the shape of the vehicle.

[0423] With the above configuration, even in a work vehicle with a special structure in which the vehicle shape can be changed, the duct can expand and contract when the vehicle shape is changed, thereby maintaining the connection between devices via the duct.

[0424] (Item C2) The work vehicle 1 described in Item C1 includes a first section and a second section that are linked to be able to move relative to each other, and the ducts 42, 43, 44 extend across the first section and the second section and have extension / contraction sections 42c, 42d, 42e, 43c, 43d, 43e, 44c that can expand and contract in response to the relative movement between the first section and the second section.

[0425] With the above configuration, by arranging the expansion / contraction sections 42c, 42d, 42e, 43c, 43d, 43e, and 44c in locations where the expansion / contraction effect is greatest, the functionality of the installed duct can be reliably maintained.

[0426] (Item C3) The work vehicle 1 according to Item C2, wherein one of the first portion and the second portion is the vehicle body 2, and the other is a traveling structure 3 disposed on the left or right side of the vehicle body 2.

[0427] With the above configuration, the ducts 42, 43 that connect the devices arranged on the vehicle body 2 and the left and right running structures 3 can be structured to have expandable and contractible sections 42e, 43e.

[0428] (Item C4) The work vehicle 1 according to Item C3, wherein the vehicle body 2 is movable in an up-down direction relative to the traveling structure 3, and the ducts 42, 43 have the extension / contraction sections 42 e, 43 e in vertical portions that are disposed between the vehicle body 2 and the traveling structure 3.

[0429] With the above configuration, the extension / contraction sections 42e, 43e extend and contract in the vertical direction in response to the vehicle body 2 rising, etc., changing its vertical position relative to the running structure 3, and the ducts 42, 43 can maintain their function as ducts that are passageways for the cooling medium.

[0430] (Item C5) The work vehicle 1 described in Item C4 includes a cooling device (air conditioning unit 51) provided on the vehicle body 2, and a cooled device (battery 37) provided on the traveling structure 3 and cooled by a cooling medium supplied from the cooling device (air conditioning unit 51), and the ducts 42, 43 extend between the cooling device (air conditioning unit 51) and the cooled device (battery 37) as a passage for the cooling medium.

[0431] With the above configuration, even when the cooling device (air conditioning unit 51) and the equipment to be cooled (battery 37) are separately located on the vehicle body 2 and the running structure 3, the two are securely connected by ducts 42 and 43 having expandable and contractible sections 42c, 42d, 42e, 43c, 43d, and 43e.

[0432] (Item C6) The work vehicle 1 according to any one of Items C2 to C5, wherein one of the first portion and the second portion is a first part of the vehicle body 2 and the other is a second part of the vehicle body 2, and the ducts 42, 43 have the extensions 42c, 42d, 43c, 43d in parts that are disposed between the first part and the second part of the vehicle body 2.

[0433] With the above configuration, even if the first part and the second part move relative to each other and the vehicle body 2 is deformed, the expansion and contraction sections 42c, 42d, 43c, and 43d can expand and contract, allowing the ducts 42 and 43 to maintain their function as ducts that are passageways for the cooling medium.

[0434] (Item C7) The work vehicle 1 described in Item C6, wherein the first portion (center battery case 24, air conditioning case 40, discharge manifold 41 b) of the vehicle body 2 and the second portion (body frame structure 20) are movable relative to each other in the front-to-rear direction, and the ducts 42, 43, 44 have the extension / contraction portions 42 c, 43 c, 44 c in portions in the front-to-rear direction that are located between the first portion (center battery case 24, air conditioning case 40, discharge manifold 41 b) of the vehicle body 2 and the second portion (body frame structure 20).

[0435] With the above configuration, even when the first part (center battery case 24, air conditioner case 40, discharge manifold 41b) and the second part (body frame structure 20) of the vehicle body 2 move relative to each other in the fore-and-aft direction, the expansion and contraction sections 42c, 43c, 44c expand and contract in the fore-and-aft direction, allowing the ducts 42, 43, 44 to maintain their function as ducts that are passageways for the cooling medium.

[0436] (Item C8) The work vehicle 1 described in Item C6 or C7, wherein the first portion (vehicle body central frame 21) and the second portion (vehicle body side frame 22) of the vehicle body 2 are capable of relative movement in the left-right direction, and the ducts 42, 43 have the extension portions 42d, 43d in left-right portions that are located between the first portion (vehicle body central frame 21) and the second portion (vehicle body side frame 22) of the vehicle body 2.

[0437] With the above configuration, even when the first part (vehicle body central 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 expansion and contraction sections 42d, 43d expand and contract in the left-right direction, allowing the ducts 42, 43 to maintain their function as ducts that are passages for the cooling medium.

[0438] (Item C9) The work vehicle 1 according to any one of Items C6 to C8, further comprising a traveling structure 3 provided on a side of the vehicle body 2, the vehicle body 2 being movable relative to the traveling structure 3, and the ducts 42, 43 having the plurality of extensions 42c, 42d, 42e, 43c, 43d, 43e provided in a portion disposed between the first portion and the second portion of the vehicle body 2 and a portion disposed between the vehicle body 2 and the traveling structure 3.

[0439] With the above configuration, when there is relative movement between the first and second parts of the car body 2, and when there is relative movement between the car body 2 and the running structure 3, the expansion and contraction sections 42c, 42d, and 42e provided in the corresponding parts expand and contract, so that the duct 42 can maintain its function as a duct for passing the cooling medium.

[0440] (Item C10) The work vehicle 1 described in Item C9, which includes a cooling device (air conditioning unit 51) provided in the first part or the second part of the vehicle body 2, and a cooled device (battery 37) provided in the traveling structure 3 and cooled by a cooling medium supplied by the cooling device (air conditioning unit 51), and in which the duct 42 extends between the cooling device (air conditioning unit 51) and the cooled device (battery 37) as a passage for the cooling medium.

[0441] With the above configuration, even when the cooling device (air conditioning unit 51) and the equipment to be cooled (battery 37) are separately located on the vehicle body 2 and the running structure 3, the two are securely connected by a duct 42 having expandable and contractible sections 42c, 42d, and 42e.

[0442] (Item C11) The work vehicle 1 described in any of Items C6 to C10, wherein the vehicle body 2 has a third portion that is movable relative to the second portion, and the ducts 42, 43 have the plurality of extension / contraction portions 42c, 42d, 43c, 43d provided in a portion (a portion where extension / contraction portions 42c, 43c are provided) that is located between the first portion (center battery case 24, air conditioner case 40, discharge manifold 41b) of the vehicle body 2 and the second portion (vehicle body central frame 21) and the third portion (vehicle body side frame 22).

[0443] With the above configuration, when the first and second parts of the vehicle body 2 move relative to each other, and when the second and third parts of the vehicle body 2 move relative to each other, the expansion and contraction sections 42c, 42d, 43c, and 43d provided in the corresponding parts expand and contract, so that the ducts 42 and 43 can maintain their function as ducts for passing the cooling medium.

[0444] (Item C12) The work vehicle 1 described in Item C11, wherein the first portion (center battery case 24, air conditioning case 40, discharge manifold 41 b) of the vehicle body 2 and the second portion (vehicle body frame structure 20) are relatively movable in the front-to-rear direction, the second portion (vehicle body central frame 21) and the third portion (vehicle body side frame 22) of the vehicle body 2 are relatively movable in the left-to-right direction, and the ducts 42, 43 have the multiple expansion and contraction portions 42 c, 42 d, 42 e, 43 c, 43 d, 43 e provided in a front-to-rear portion that is located between the first portion (center battery case 24, air conditioning case 40, discharge manifold 41 b) of the vehicle body 2 and the second portion (vehicle body frame structure 20) and in a left-to-right portion that is located between the second portion (vehicle body central frame 21) and the third portion (vehicle body side frame 22) of the vehicle body 2.

[0445] With the above configuration, when the first and second parts of the vehicle body 2 move relative to each other in the longitudinal direction, and when the second and third parts of the vehicle body 2 move relative to each other in the lateral direction, the expansion and contraction sections 42c, 42d, 43c, and 43d provided in the corresponding parts expand and contract, so that the ducts 42 and 43 can maintain their function as ducts for passage of the cooling medium.

[0446] (Item C13) The work vehicle 1 according to Item C12, further comprising: a traveling structure 3 provided on a side of the vehicle body 2; a cooling device (air conditioning unit 51) provided in the first portion (center battery case 24, air conditioning case 40, discharge manifold 41 b) of the vehicle body 2; and a cooled device (battery 37) that is disposed on the traveling structure 3 and is cooled by a cooling medium supplied from the cooling device (air conditioning unit 51), wherein the ducts 42, 43 serve as passages for the cooling medium, extending in the front-to-rear direction from the cooling device (air conditioning unit 51) to the second portion (vehicle body center frame 21) of the vehicle body 2, bending at the second portion (vehicle body center frame 21) of the vehicle body 2, extending in the left-to-right direction from the second portion (vehicle body center frame 21) to the third portion (vehicle body side frame 22), and extending in the up-and-down direction from the third portion (vehicle body side frame 22) of the vehicle body 2 to the cooled device (battery 37).

[0447] With the above configuration, the duct 42 is arranged along an excellent route to connect the cooling device (air conditioning unit 51) on the vehicle body 2 with the equipment to be cooled (battery 37) on the running structure 3, and to achieve a compact and efficient piping structure within the work vehicle 1. Such duct 43 is provided with the aforementioned expansion and contraction sections 42c, 42d, 42e, 43c, 43d, and 43e, so that the duct 43 can maintain its function as a duct that is a passage for a cooling medium by expanding and contracting the expansion and contraction sections 42c, 42d, 42e, 43c, 43d, and 43e in response to the relative movement between the first and second sections of the vehicle body 2, the relative movement between the second and third sections, or the relative movement between the vehicle body 2 and the running structure 3.

[0448] (Item D1) A vehicle includes a vehicle body 2 and left and right traveling structures 3L, 3R provided on the left and right sides of the vehicle body 2, and the vehicle body 2 is provided with a first device D1 (a working electric unit E1, a hydraulic electric unit E2) and a first adjusting device T1 (a radiator 52) that adjusts the temperature of the first device D1 (the working electric unit E1, the hydraulic electric unit E2). One of the left and right traveling structures 3L, 3R (the left traveling structure 3L) is provided with a second device D2L (a left front traveling system electric unit E2). The work vehicle 1 is provided with a second adjustment device T2L (radiator 71) that adjusts the temperature of the second equipment D2L, and a third equipment D2R (right front running system electric unit E3FR, right rear running system electric unit E3RR) and a third adjustment device T2R (radiator 71) that adjusts the temperature of the third equipment D2R arranged on the other of the left and right running structures 3L, 3R (right running structure 3R).

[0449] With the above configuration, in a work vehicle 1 in which the body 2 and the left and right running structures 3 are provided with the equipment D1, D2L, D2R (working system electric unit E1, hydraulic system electric unit E2, left front running system electric unit E3FL, left rear running system electric unit E3RL, right front running system electric unit E3FR, right rear running system electric unit E3RR) that is to be temperature regulated, the body 2 and each running structure 3 are provided with their own adjusting devices T1, T2L, T2R (radiators 52, 71), so the temperature regulation effect of each device can be improved, and even if some kind of trouble occurs with the temperature regulation function of one device, the devices provided in other parts (body 2 or running structures 3) will not be affected. Furthermore, even when the car body 2 and the left and right running structures 3L, 3R are separated, adjustment devices for adjusting the temperature of each piece of equipment are provided in each of the car body 2 and the left and right running structures 3L, 3R, so the number of connections required for piping, etc. for sending temperature adjustment medium to adjust the temperature of each piece of equipment between the car body 2 and the left and right running structures 3L, 3R can be reduced, improving maintainability, etc.

[0450] (Item D2) The work vehicle 1 according to 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.

[0451] With the above configuration, the water-cooling effect of the radiators 52, 71 can be reliably applied to the corresponding equipment D1, D2L, D2R (working electric unit E1, hydraulic electric unit E2, left front traveling electric unit E3FL, left rear traveling electric unit E3RL, right front traveling electric unit E3FR, right rear traveling electric unit E3RR).

[0452] (Item D3) The work vehicle 1 according to Item D2, wherein the first adjustment device is a radiator 52 and is disposed at the front of the vehicle body 2.

[0453] With the above-described configuration, the radiator 52 is disposed at a position where it is easy to take in air for heat exchange, thereby enhancing the temperature adjustment effect.

[0454] (Item D4) The work vehicle 1 described in any one of Items D1 to D3, wherein the vehicle body 2 is provided with a first adjustment circuit C1 (R1) that circulates a temperature adjustment medium between the first adjustment device T1 (radiator 52) and the first equipment D1 (work 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) that circulates a temperature adjustment medium between the second adjustment device T2L (radiator 71) and the second equipment D2L (left traveling system electric unit E2L), and the other traveling structure 3 (right traveling structure 3R) is provided with a third adjustment circuit C2R (R2R) that circulates a temperature adjustment medium between the third adjustment device T2R (radiator 71) and the third equipment D2R (right traveling system electric unit E2R). (Item D4) The work vehicle 1 described in any one of Items D1 to D3, wherein the vehicle body 2 is provided with a first adjustment circuit C1 (R1) that circulates a temperature adjustment medium between the first adjustment device T1 (radiator 52) and the first equipment D1 (work 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) that circulates a temperature adjustment medium between the second adjustment device T2L (radiator 71) and the second equipment D2L (left traveling system electric unit E2L).

[0455] With the above configuration, adjustment circuits C1, C2L, C2R are configured to circulate a temperature adjustment medium between the adjustment devices T1, T2L, T2R and the equipment D1, D2L, D2R provided separately in each of the vehicle body 2 and the left and right running structures 3L, 3R, so that even if a problem occurs in one of the circuits, it will not affect the other circuits, making it easy to maintain the temperature adjustment effect of each device within the work vehicle 1. Furthermore, when separating and connecting the vehicle body 2 and the left and right running structures 3L, 3R, it is possible to avoid the trouble of separating and connecting piping between the adjustment circuits C1, C2L, C2R, resulting in excellent maintainability.

[0456] (Item D5) The work vehicle 1 described in Item D4, wherein at least one of the first adjustment device T1, the second adjustment device T2L, and the third adjustment device T2R includes a radiator 52, 71 and a radiator fan 52a, 71a, and the first adjustment circuit R1 (C1), the second adjustment circuit R2L (C2L), or the third adjustment circuit R2R (R2R) connected to the radiator 52, 71 includes a cooling water storage tank 59, 73 and a cooling water discharge pump 58, 72.

[0457] With the above configuration, at least one of the vehicle body 2 and the left and right running structures 2L, 3R is provided with a water-cooled cooling (temperature adjustment) circuit R1, R2L, R2R (C1, C2L, C2R) including a radiator or the like.

[0458] (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 conditioning unit 51).

[0459] With the above-described configuration, the air temperature adjusting device (air conditioning unit 51) can provide an air-cooled cooling (temperature adjusting) effect to at least one of the vehicle body 2 and the left and right running structures 2L, 3R.

[0460] (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.

[0461] With the above-described configuration, it is possible to adjust the temperature of the equipment provided on at least one of the vehicle body 2 and the left and right running structures 2L, 3R by supplying hot water heated by a heater, for example.

[0462] (Item D8) A work vehicle 1 described in any one of Items D1 to D6, wherein the left and right running structures 3 each have a wheel 5, and the second adjustment device T2L (radiator 71) and the third adjustment device T2R (radiator 71) are each positioned to face the contact surfaces of the wheels 5 of the running structures 3.

[0463] With the above configuration, the adjustment device (radiator 71) can be positioned on the running structure 3, which has a limited left-right width, so as not to extend beyond the left-right width of the contact surface of the wheels 5 as much as possible.

[0464] (Item D9) The work vehicle 1 according to item D8, wherein the second adjustment device T2L and the third adjustment device T2R are radiators 71, and are each inclined with respect to the front-to-rear direction in front of the wheels 5.

[0465] With the above configuration, the radiator 71 has a fairly large width in the left-right direction when placed facing each other in the fore-and-aft direction, but by tilting it relative to the fore-and-aft direction, it is mounted on the running structure 3 so that it fits within the left-and-right width of the contact surface of the wheel 5 as described above.

[0466] (Item D10) The work vehicle 1 described in any one of Items D1 to D9, wherein the first device D1 is electrical equipment (work system electric unit E1) for driving and controlling a work implement connected to the vehicle body 2 and / or hydraulic equipment (hydraulic pump 57) for controlling hydraulic actuators (width change cylinder 8, vehicle body lifting cylinder 9) equipped on the vehicle body 2.

[0467] With the above configuration, the first adjustment device T1 (air conditioning unit 51, radiator 52, etc.) can provide temperature adjustment to electrical equipment and hydraulic equipment in the vehicle body 2 that particularly require temperature adjustment (cooling).

[0468] (Item D11) The work vehicle 1 according to items D1 to D10, wherein the second device D2L and the third device D2R are each a traveling motor 7 that drives the wheels 5 of the traveling structure 3.

[0469] With the above configuration, the travel motor 7, which is the main driving device in the travel structure 3, can be subjected to temperature adjustment by the second adjustment device T2L and the third adjustment device T2R (radiator 71, etc.).

[0470] (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 on any one of the vehicle body 2, the left traveling structure 3L, and the right traveling structure 3R; temperature adjustment target devices whose temperature is adjusted by the temperature adjustment device T3 (radiator 52), the temperature adjustment target devices including a first device D1 arranged on the vehicle body 2, a second device D2L arranged on the left traveling structure 3L, and a third device D2R arranged on the right traveling structure 3R; 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, wherein the temperature adjustment circuit C3 branches off from the temperature adjustment device T3 (radiator 52) and is connected to the first device D1, the second device D2L, and the third device D2R, respectively.

[0471] With the above configuration, temperature-adjusted medium can be supplied from a single temperature adjustment device T3 (radiator 52) via a branched temperature adjustment circuit C3 to multiple temperature-adjusted devices provided on the vehicle body 2 and the left and right running structures 3L, 3R, and by sharing the temperature adjustment device T3, the number of parts and costs can be reduced.

[0472] (Item E2) The work vehicle described in Item E1, wherein 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 (radiator 52, 71) and the first equipment D1, a second temperature adjustment circuit (branch circulation circuit) C3b that circulates a temperature adjustment medium between the temperature adjustment device T3 (radiator 52, 71) and the second equipment D2L, and a third temperature adjustment circuit (branch circulation circuit) C3c that circulates a temperature adjustment medium between the temperature adjustment device T3 (radiator 52, 71) and the third equipment D2R.

[0473] With the above configuration, a temperature control medium circulation circuit is formed in which the temperature control medium is circulated between multiple devices, for example, around the front running system electric unit E3F (front running motor 7F) and the rear running system electric unit E3R (rear running motor 7R) in each of the vehicle body 2, left running structure 3L, and right running structure 3R, and then returned to the common temperature control device T3 (radiators 52, 71).

[0474] (Item E3) The work vehicle 1 according to item E1 or E2, wherein the temperature adjustment device T3 is a radiator 52, 71.

[0475] With the above configuration, the water cooling effect of the radiators 52, 71 can be reliably imparted to the devices D1, D2L, D2R provided on the vehicle body 2 and the left and right running structures 3L, 3R.

[0476] (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 a radiator 52, 71.

[0477] With the above-described configuration, it is possible to reliably cool the batteries 50, 37, which require temperature management in order to enable the electrical equipment and the like to operate properly, even in the work vehicle 1.

[0478] (Item E5) The work vehicle 1 described in item E3 or E4, wherein at least one of the first device D1, the second device D2L, and the third device D2R is an electrical device (work system electric unit E1, hydraulic system electric unit E2, traveling system electric units E3FL, E3FR, E3RL, E3RR) cooled by cooling water from radiators 52, 71.

[0479] With the above configuration, the second adjustment device T2L and the third adjustment device T2R (radiator 71, etc.) can exert a temperature adjustment effect on the traveling motor 7, which is an electrical device that particularly requires temperature adjustment (cooling) among the traveling structure 3.

[0480] (Item E6) The work vehicle 1 according to any one of items E1 to E5, wherein the temperature adjustment device T3 is an air temperature adjustment device (air conditioning unit 51).

[0481] With the above configuration, the air temperature adjustment device (air conditioning unit 51) can provide an air-cooled cooling (temperature adjustment) effect to the temperature adjustment target devices D1, D2L, and D2R installed on the vehicle body 2 and the left and right running structures 2L and 3R.

[0482] (Item E7) The work vehicle 1 according to Item E6, wherein at least one of the first device D1, the second device D2, and the third device D3 is a battery 50 cooled by cooling air from an air temperature adjustment device (air conditioning unit 51).

[0483] With the above configuration, an air-cooled cooling (temperature adjustment) effect can be exerted by the air temperature adjustment device (air conditioning unit 51) on the temperature adjustment target equipment D1, D2L or D2R installed on the vehicle body 2 and any of the left and right running structures 2L, 3R.

[0484] (Item E8) The work vehicle 1 according to item E1 or E2, wherein the temperature adjustment device T3 is a heater.

[0485] With the above configuration, a temperature-adjusted refrigerant such as hot water whose temperature has been adjusted by a heater can be supplied to the temperature-adjusted devices D1, D2L, and D2R provided on the vehicle body 2 and the left and right running structures 2L and 3R.

[0486] Although the embodiments of the present invention have been described above, the embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims.

[0487] REFERENCE SIGNS LIST 1 Work vehicle 2 Vehicle body 3 Travel structure 3L Left travel structure 3R Right travel structure 24 Center battery case 24c Cooling air passage 24d Exhaust air passage 24e Partition plate 24g Communication passage 24h Intake 36 Side battery case 37 Side battery 43 Return duct 50 Center battery 51 Air conditioning unit

Claims

1. A work vehicle comprising 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 for housing the first cooling target device, and a second cooling housing for housing the second cooling target device, wherein the first cooling housing is provided with an intake port for taking in air discharged from the second cooling housing after cooling the second cooling target device.

2. In the first cooling housing, a cooling air passage for directing cooling air from the cooling device to the first cooling target device and an exhaust air passage for discharging air after cooling the first cooling target device to the cooling device are formed, and the air from the second cooling housing introduced into the first cooling housing through the intake port merges with the air in the exhaust air passage. The work vehicle according to claim 1.

3. In the first cooling housing, a first air guiding device for guiding air from the cooling air passage to the exhaust air passage and a second air guiding device for guiding air from the intake port to the exhaust air passage are provided. The work vehicle according to claim 2.

4. In the first cooling housing, a partition plate is provided above the first cooling target device, and a space below the partition plate in the first cooling housing is the cooling air passage, and a space above the partition plate is the exhaust air passage. The work vehicle according to claim 2.

5. In the first cooling housing, a vertical communication passage communicating the outlet of the cooling air passage and the inlet of the exhaust air passage is provided along the end of the partition plate. At the outlet of the cooling air passage, a first air guiding device for guiding air from the cooling air passage to the lower part of the communication passage is provided, and at the upper part of the communication passage, the intake port and a second air guiding device for guiding air introduced from the intake port to the inlet of the exhaust air passage are provided. The work vehicle according to claim 4.

6. The first air guiding device and the second air guiding device are fans. The work vehicle according to claim 3 or 5.

7. At least one of the first cooling target device and the second cooling target device is a battery. The work vehicle according to claim 1.

8. A work vehicle comprising a vehicle body and a traveling structure provided on the side of the vehicle body, wherein the cooling device and the first cooling housing are arranged on the vehicle body, and the second cooling housing is arranged on the traveling structure. The work vehicle according to claim 1, 2 or 7.

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