Work vehicles

Abstract

The present invention provides a work vehicle in which the assembly of electrical wiring and cooling water piping is easy, and the electrical wiring and cooling water piping are compactly arranged around the motor. [Solution] The work vehicle comprises a vehicle body, a running structure that supports the vehicle body so that it can move, a motor that drives equipment mounted on the vehicle body or the running structure, a connection box attached to the motor, electrical wiring housed inside the connection box that supplies power to the power connection terminals of the motor, and cooling water piping housed inside the connection box that guides cooling water to the cooling water inlet and outlet of the motor.

Description

Technical Field

[0001] The present disclosure relates to a work vehicle.

Background Art

[0002] Non-Patent Document 1 describes a motor that uses water as a cooling method. A motor cooled by water (hereinafter sometimes referred to as a "water-cooled motor") can be cooled more efficiently than a normal air-cooled motor, so it is used under high-temperature environments and high-load operating conditions. Due to efficient cooling, the motor itself can be miniaturized.

Prior Art Documents

Non-Patent Documents

[0003]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the case of a water-cooled motor, electrical wiring is connected to the connection terminals of the motor, and a cooling water pipe is connected to the cooling water inlet and outlet of the motor. For this reason, the assembly has been complicated. In addition, since a space for arranging electrical wiring and a cooling water pipe around the motor is required, it has been difficult to achieve a compact layout.

[0005] In view of the above problems, an object of the present disclosure is to provide a work vehicle in which the assembly of electrical wiring and a cooling water pipe is easy, and the electrical wiring and the cooling water pipe are arranged compactly around the motor.

Means for Solving the Problems

[0006] A work vehicle according to one aspect of the present disclosure comprises a vehicle body, a running structure that supports the vehicle body so as to be able to move, a motor that drives equipment mounted on the vehicle body or the running structure, a connection box attached to the motor, electrical wiring housed in the connection box that supplies power to the power connection terminals of the motor, and cooling water piping housed in the connection box that guides cooling water to the cooling water inlet and outlet of the motor. [Effects of the Invention]

[0007] According to this disclosure, the assembly of electrical wiring and cooling water piping can be easily performed, and the placement of electrical wiring and cooling water piping around the motor can be made compact. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a perspective view showing one form of implementation using a work vehicle. [Figure 2] Figure 2 is a perspective view of the work vehicle. [Figure 3] Figure 3 is a plan view of the work vehicle shown in Figure 2. [Figure 4] Figure 4 is a left side view of the work vehicle shown in Figure 2. [Figure 5] Figure 5 is a right side view of the work vehicle shown in Figure 2. [Figure 6] Figure 6 is a diagram showing the configuration of the work vehicle. [Figure 7] Figure 7 is a schematic diagram showing a deformed work vehicle. [Figure 8] Figure 8 is a schematic diagram showing a deformed work vehicle. [Figure 9] Figure 9 is a schematic diagram showing a deformed work vehicle. [Figure 10] Figure 10 is a schematic diagram showing a deformed work vehicle. [Figure 11] Figure 11 is a perspective view showing an overview of the running gear. [Figure 12] Figure 12 is a side view of the connection box with the lid removed.

Mode for Carrying Out the Invention

[0009] <Summary of Embodiments of the Present Disclosure> The summary of the embodiments of the present disclosure will be listed and described below.

[0010] (1) A work vehicle according to one aspect of the present disclosure includes a vehicle body, a traveling structure that supports the vehicle body so as to be capable of traveling, a motor that drives equipment mounted on the vehicle body or the traveling structure, a connection box attached to the motor, electrical wiring that is installed inside the connection box and sends power to the power connection terminals of the motor, and cooling water piping that is installed inside the connection box and guides cooling water to the cooling water inlet and outlet of the motor.

[0011] Thereby, the assembly of the electrical wiring and the cooling water piping can be facilitated, and the arrangement of the electrical wiring and the cooling water piping on the motor can be made compact.

[0012] (2) In the work vehicle according to (1) above, the electrical wiring and the cooling water piping may be introduced into the motor from the side opposite to the output side of the motor.

[0013] Thereby, the connection box and the motor will be located on the same axis, enabling a compact arrangement.

[0014] (3) In the work vehicle according to (1) above, the motor and the connection box are provided on the traveling structure, the motor is located closer to the vehicle body center side than the connection box, and at least a part of the connection box may overlap the motor in a side view of the vehicle body.

[0015] Thereby, the connection box will be located in a direction outside the vehicle body rather than the motor, making it easier for an operator to approach the connection box and facilitating the assembly and maintenance of wiring and the like.

[0016] (4) In the work vehicle according to any one of (1) to (3) above, the connection box may have a hole that opens at the bottom.

[0017] When there is a leak of cooling water, the water drops from the hole, so it is possible to easily detect the leak of cooling water. Also, since the leaked cooling water does not accumulate in the connection box, it is possible to suppress electric leakage in the electrical system.

[0018] (5) In the work vehicle according to any one of (1) to (4) above, the connection box has a mounting plate attached to the motor, and a first side wall and a second side wall that intersect the mounting plate, and the electrical wiring penetrates the first side wall, and the cooling water pipe may penetrate the second side wall different from the first side wall.

[0019] Since the electrical wiring and the cooling water pipe are introduced into the connection box from different side surfaces, the connection box can be configured more compactly than when they are introduced into the connection box from the same side surface.

[0020] (6) In the work vehicle according to any one of (1) to (5) above, a signal wiring of a sensor for detecting the state of the motor may be further installed inside the connection box.

[0021] Thereby, the work vehicle can perform motor control according to the state of the motor.

[0022] <Details of Embodiment of Invention> Hereinafter, details of an embodiment of the invention will be described with reference to the drawings. Note that at least a part of the embodiments described below may be arbitrarily combined.

[0023] [1-1. Overall Configuration of Work Vehicle] Figures 1 and 2 are perspective views showing one embodiment of a work vehicle. This work vehicle 10 has an exterior member 9, and Figure 2 shows the exterior member 9 removed. The exterior member 9 is attached to the frames 20 and 21 of the work vehicle 10. The exterior member 9 protects the various components of the work vehicle 10 and enhances its aesthetic appearance. Figures 3, 4, and 5 are a top view, left side view, and right side view of the work vehicle 10 shown in Figure 2. Figure 6 is a diagram showing the configuration of the work vehicle 10.

[0024] The work vehicle 10 has a running gear 12 and travels on fields and roads. In the case of the work vehicle 10 of this embodiment, the direction pointed to by arrow X1 in each figure is the basic direction of travel and is defined as "forward". In each figure, the direction pointed to by arrow X2 is the opposite direction of the basic direction of travel and is defined as "rear". In each figure, the direction pointed to by arrow Y1 is defined as "left", the direction pointed to by arrow Y2 is defined as "right", the direction pointed to by arrow Z1 is defined as "up", and the direction pointed to by arrow Z2 is defined as "down".

[0025] The work vehicle 10 is capable of moving straight in both forward and backward directions, as well as turning left (left turn) and turning right (right turn), thanks to its running gear 12. The running gear 12 is located at four locations on the front, rear, left, and right sides of the vehicle body 11, and each running gear 12 has wheels 25. The work vehicle 10 has a hydraulic motor, which allows the direction of the wheels 25 (the direction in which the wheels 25 roll) to be changed within a 360-degree range. Therefore, the work vehicle 10, which can move forward and backward, can move in a straight line in all 360 degrees. Note that an electric motor may be used instead of the hydraulic motor. Alternatively, the work vehicle 10 may be able to change the direction of the wheels 25 from the basic direction of travel within a range of 0 to 90 degrees, for example, by a hydraulic cylinder. When the direction of the wheels 25 changes by 90 degrees from the basic direction of travel, its rolling direction becomes either left or right. The work vehicle 10 can also move straight in either the left or right direction. Furthermore, the work vehicle 10 may be able to change the direction of its wheels 25 within a range of 0 to -90 degrees using the hydraulic cylinder, from its initial state in the basic direction of travel. Since the direction of the wheels 25 can be changed within a range of 0 to 90 degrees and within a range of 0 to -90 degrees from its initial state in the basic direction of travel, and since it is possible to move forward and backward, the work vehicle 10 can move in a straight line in all 360 degrees.

[0026] The work vehicle 10 connects to the work machine 19 via a coupling device 15. Figures 1, 2, 4, and 5 show the work machine 19 as a dashed line. The work machine 19 has a configuration and functions for performing various tasks. The tasks performed by the work machine 19 include, but are not limited to, agricultural work, industrial work (civil engineering, construction, etc.), and transportation work. The work vehicle 10 travels together with the work machine 19, while the work machine 19 performs its tasks.

[0027] In this embodiment, the work performed by the implement 19 is agricultural work. The implement 19 is, for example, a spraying device for applying fertilizer or chemicals to a field, a seeding device for sowing seeds, a tilling device for cultivating the soil, a tilling device for tilling the soil, a weeding device for weeding, a soil mounding device for mounding soil, etc. The implement 19 is replaced according to the required work.

[0028] The components of the work vehicle 10 will now be described. The work vehicle 10 has one vehicle body 11 and four running gears 12 for moving the vehicle body 11. The work vehicle 10 in this embodiment has a coupling device 15 attached to the vehicle body 11. The coupling device 15 is a device for connecting a work machine 19 to the vehicle body 11. The coupling device 15 has a lifting mechanism 70 for raising and lowering the work machine 19. The specific configuration of the coupling device 15 will be described later.

[0029] The coupling device 15 allows the work equipment 19 to be detached. The work vehicle 10 allows the coupling device 15 to be detached. If the work equipment 19 is not needed for the work vehicle 10, the work equipment 19 is detached from the coupling device 15. Furthermore, the coupling device 15 may be detached from the vehicle body 11. The work vehicle 10 can run with the coupling device 15 attached, even if the work equipment 19 has been detached, and the work vehicle 10 can also run with both the coupling device 15 and the work equipment 19 detached from the vehicle body 11.

[0030] The vehicle body 11 has a central frame 20 and a pair of side frames 21, 21 located on the left and right sides of the central frame 20. The left side frame 21 may be described as "21L" and the right side frame 21 as "21R". The running gear 12, including the wheels 25, is mounted on the side frames 21. Each of the pair of side frames 21, 21 is displaceable relative to the central frame 20, and the work vehicle 10 can be deformed according to the work content or usage conditions such as the shape of the road surface.

[0031] Figures 7, 8, 9, and 10 are schematic diagrams showing a deformed work vehicle 10. As shown in Figures 7 and 8, the central frame 20 and the left side frame 21L and the right side frame 21R are relatively displaceable in the left-right and up-down directions. The left side frame 21L and the right side frame 21R are independently displaceable. The work vehicle 10 has displacement actuators 13 that allow the central frame 20 and the side frames 21L and 21R to be displaced relatively in the left-right and up-down directions.

[0032] The work vehicle 10 has left and right actuators 131 and up and down actuators 132 as displacement actuators 13. The left and right actuators 131 (see Figure 7) extend and retract, displacing the side frames 21L and 21R, respectively, in the left and right directions relative to the central frame 20. As a result, the work vehicle 10 changes the distance between the left and right wheels 25 according to the width of the furrows in the field, for example, and travels accordingly.

[0033] The vertical actuator 132 (see Figure 8) extends and retracts, displacing the central frame 20 vertically relative to the side frames 21L and 21R. The central frame 20 becomes higher than the side frames 21L and 21R. As a result, the work vehicle 10 changes the position of the central frame 20 vertically according to the height of the furrows in the field, for example, and travels while straddling the furrows.

[0034] The central frame 20 and the side frames 21L and 21R each only need to be displaceable in at least one of the left-right and up-down directions relative to each other. To this end, the work vehicle 10 only needs to have displacement actuators 13 in the direction that allows the side frames 21L and 21R to be displaced.

[0035] The longitudinal deformation of the vehicle body 11 occurs within the central frame 20. That is, as shown in Figure 10, the central frame 20 mounts the battery 16 (first battery 16A) and the case 205 that houses the battery 16. The case 205 can be displaced in the longitudinal direction by the longitudinal actuators 133. The battery 16 (first battery 16A) is heavy. As the battery 16 (first battery 16A) is displaced in the longitudinal direction within the central frame 20, the vehicle body 11 deforms, and its center of gravity can be changed. For example, when the work vehicle 10 travels on an inclined surface, it changes its center of gravity depending on its posture or depending on the work machine 19 it is connected to.

[0036] As another example of the deformation of the work vehicle 10 in the longitudinal direction (see Figure 9), the work vehicle 10 may have a longitudinal actuator 133 as a displacement actuator 13, and the longitudinal actuator 133 may extend and retract to relatively displace the central frame 20 and the side frames 21L and 21R, respectively, in the longitudinal direction. By displacing the central frame 20 in the longitudinal direction, the center of gravity of the vehicle body 11 can be changed.

[0037] Thus, in the configurations shown in Figures 7 and 8, the central frame 20 and the side frames 21L and 21R are each displaceable relative to each other in at least one of the left-right and up-down directions. The displacement actuator 13 displaces the central frame 20 and the side frames 21L and 21R relative to each other in at least one of the left-right and up-down directions. As shown in Figure 10, the central frame 20 has a case 205 that houses the battery 16 (first battery 16A). The case 205 is housed in the central frame 20 and is displaceable in the front-rear direction. The displacement actuator 13 displaces the case 205 in the front-rear direction within the central frame 20.

[0038] Each of the above-described forms of work vehicle 10 deforms its vehicle body 11 according to, for example, the shape of the road surface it is traveling on. The work vehicle 10 can operate with the work machine 19 while traveling with the vehicle body 11 deformed.

[0039] The work vehicle 10 (see Figures 2 to 5) has four running gears 12 located on the front, rear, left, and right sides of the vehicle body 11. The running gears 12 are attached to each of the left and right side frames 21. The left front running gear 12 may be described as "12LF", the right front running gear 12 as "12RF", the left rear running gear 12 as "12LR", and the right rear running gear 12 as "12RR".

[0040] Each running gear 12 has wheels 25, a motor 26 for driving, a reduction gear 27, and a power transmission unit 28 including gears and shafts. The rotational force of the motor 26 is reduced by the reduction gear 27, and the reduced power is transmitted to the wheels 25 through the power transmission unit 28, causing the wheels 25 to rotate. As a result, the work vehicle 10 moves.

[0041] The left front running gear 12LF and the left rear running gear 12LR are mounted on the left side frame 21L, and together they constitute the left running unit UL. The left running unit UL (hereinafter referred to as the left running unit UL) includes the left second battery 16L, a sub-junction box 24L, and inverters 31 connected to the two running motors 26, respectively, which are mounted on the side frame 21L. The right front running gear 12RF and the right rear running gear 12RR are mounted on the right side frame 21R, and together they constitute the right running unit UR. The right running unit UR (hereinafter referred to as the right running unit UR) includes the right second battery 16R mounted on the side frame 21R, the sub-junction box 24R, and inverters 31 connected to the two running motors 26, one at the front and one at the rear. The left running unit UL and the right running unit UR correspond to the "running structure". The running device 12 has wheels 25, a motor 26 for running, a reduction gear 27, and a power transmission unit 28 including gears and shafts, so the motor 26 is a motor that drives the equipment (wheels 25, reduction gear 27, power transmission unit 28) mounted on the running structure. The central frame 20 houses the first battery 16A, the hydraulic unit 17, and the main junction box 24A, among other components, and together these constitute the central unit UC. The central unit UC corresponds to the "vehicle body." Therefore, the running structure supports the vehicle body in a way that allows it to move. In this embodiment, as described above (see Figure 9), the case 205 housing the first battery 16A is displaced in the front-rear direction within the central frame 20. In contrast, the hydraulic unit 17 and other equipment, including the main junction box 24A, are not displaced in the front-rear direction.

[0042] The work vehicle 10 has steering actuators 29 that change the rolling direction of each of the four wheels 25 of the running gear 12 (see Figure 3). In this embodiment, the running gear 12 is supported by the side frame 21 and is capable of swinging around its vertical axis. The steering actuator 29 is mounted between the side frame 21 and the running gear 12. The steering actuator 29 changes the orientation of the running gear 12 by extending and retracting. This changes the rolling direction of the wheels 25, and thus changes the direction of travel of the work vehicle 10.

[0043] The work vehicle 10 includes a control device 14, a battery 16, a hydraulic unit 17, and a cooling unit 23. The control device 14 controls the operation of each piece of equipment in the work vehicle 10, including the travel device 12 (motor 26), displacement actuator 13, steering actuator 29, hydraulic unit 17, and cooling unit 23.

[0044] Battery 16 is a rechargeable battery that can be discharged and recharged. Battery 16 supplies power to each piece of equipment in the work vehicle 10. In this embodiment (see Figure 6), the work vehicle 10 has one first battery 16A and two second batteries 16L and 16R. The first battery 16A is mounted on the central frame 20. One second battery 16L is mounted on the left side frame 21L, and the other second battery 16R is mounted on the right side frame 21R.

[0045] In this embodiment, the displacement actuator 13 and the steering actuator 29 are composed of hydraulic cylinders. The hydraulic unit 17 generates hydraulic pressure to extend and retract the hydraulic cylinders. The hydraulic unit 17 includes a tank for storing hydraulic fluid, a hydraulic pump, a motor 171 for driving the hydraulic pump, various valves, and hydraulic piping. The hydraulic unit 17 is mounted at the rear of the central frame 20. Therefore, the motor 171 is a motor that drives equipment mounted on the vehicle body.

[0046] The coupling device 15 (see Figure 4) has a hydraulic cylinder 73 as an actuator for raising and lowering the work equipment 19. The hydraulic unit 17 of the vehicle body 11 has hydraulic piping for supplying hydraulic pressure to the coupling device 15 (hydraulic cylinder 73). Furthermore, when the work equipment 19 is operated hydraulically, the hydraulic unit 17 has hydraulic piping for supplying hydraulic pressure to the work equipment 19. These hydraulic pipes are connected to a vehicle-side coupling of the vehicle body 11. The vehicle-side coupling is provided at the rear of the vehicle body 11 (central frame 20) and at the lower fixing portion 41.

[0047] When the coupling device 15 is attached to the fixing part 41 of the vehicle body 11, the coupling of the coupling device 15 is connected to the vehicle-side coupling. The hydraulic piping of the coupling device 15 is connected to this coupling, and hydraulic fluid from the hydraulic unit 17 is supplied through the hydraulic piping to the hydraulic cylinder 73 of the coupling device 15 and the hydraulic equipment of the work machine 19.

[0048] The cooling unit 23 (see Figure 3) includes a first cooling unit 231 for cooling the battery 16 (16A, 16L, 16R), a second cooling unit 232 for cooling the motor 171 that drives the hydraulic pump of the hydraulic unit 17, and a third cooling unit 233 for cooling the motor 26 of the traveling device 12. Each cooling unit has a heat exchanger or the like for cooling the cooling medium.

[0049] The first cooling unit 231 and the second cooling unit 232 are mounted on the central frame 20 and are located in front of the first battery 16A. The third cooling unit 233 is mounted on the front of each of the side frames 21L and 21R. In this embodiment, the first cooling unit 231 is air-cooled, while the second cooling unit 232 and the third cooling unit 233 are water-cooled.

[0050] The work vehicle 10 (see Figure 6) has a junction box 24 and inverters 31 connected to each motor. In this embodiment, the junction box 24 has a main junction box 24A and sub-junction boxes 24L and 24R. The main junction box 24A is mounted on the central frame 20. The sub-junction boxes 24L and 24R are mounted on the side frames 21L and 21R. Each inverter 31 receives power from the main junction box 24A or the sub-junction boxes 24L and 24R and outputs a predetermined amount of power to each motor.

[0051] The work vehicle 10 has a charging port 32, a DC-DC converter 33, and an OBC / DC-DC converter 34. The DC-DC converter 33 transforms (steps down or steps up) the power supplied from the battery 16A to supply to other electrical equipment such as the control device 14. The OBC / DC-DC converter 34 includes an onboard charger and a DC-DC converter. The OBC / DC-DC converter 34 is connected to the charging port 32. The charging port 32 is mounted on the vehicle body 11 and is connected to an external power source located at a charging station or the like. The OBC / DC-DC converter 34 converts the power supplied from the charging port 32 into power to charge the battery 16A.

[0052] [1-2. Details of the drive motor] Figure 11 is a perspective view showing an overview of the travel device 12. The case where the travel motor 26 is a water-cooled motor will be explained in detail based on Figure 11. A connection box 110 is attached to the motor 26. The connection box 110 includes a connection box body 111 and a lid 112. If the motor 171 that drives the hydraulic pump is a water-cooled motor, the motor 171 has a similar configuration. The following explanation will use the case where motor 26 is a water-cooled motor as an example to describe each configuration.

[0053] <motor> Motor 26 is a motor for operating the work vehicle 10. The work vehicle 10 is an electric vehicle for performing agricultural work. Therefore, it is desirable that motor 26 meets the following requirements. (1) The motor output must be sufficient for agricultural work. (2) Some agricultural tasks cannot be performed at a specific time, for example, if harvesting is not done at the optimal time, the yield and quality will decrease. For this reason, the reliability of the motor is important. Water-cooled motors are used to meet these requirements.

[0054] Water-cooled motors have the following characteristics: (1) By using a water cooling system, the cooling efficiency is higher compared to air cooling. Therefore, the size and weight of the motor can be reduced. (2) Water-cooled motors are suitable for applications requiring high output because they are less likely to generate heat during operation under high load. (3) Because the water cooling system cools the motor and prevents heat buildup, water-cooled motors have higher reliability than air-cooled motors.

[0055] A water-cooled motor, like a conventional motor, includes a stator, rotor, shaft, and bearings in its basic configuration. The stator is the fixed coil part that generates a magnetic field. The rotor is the rotating part that rotates through magnetic interaction with the stator. The shaft is the output shaft of the motor, connected to the rotor, and outputs mechanical power to the outside. The bearings support the shaft. A water-cooled motor has a cylindrical shape, and the shaft is exposed to the outside from one end face. When power is supplied to the stator, the rotor rotates due to the magnetic interaction between the stator and rotor. The generated rotational motion is output from the shaft connected to the rotor.

[0056] The water-cooled motor further comprises a configuration (not shown) for cooling the motor. This configuration includes cooling pipes (not shown) for guiding cooling water to cool the motor. The cooling pipes are arranged to be wound around the stator or to circulate inside the stator. The cooling pipes may be made of any material that conducts heat well and is not corrosive to the cooling water, such as copper, aluminum, or their alloys. The cooling water may be water, for example, but may contain various additives such as antifreeze to prevent freezing. The cooling water circulating around the stator removes heat from the stator. The cooling water is cooled by heat exchange with the outside air by a heat dissipation unit provided separately from the motor.

[0057] <Connection Box> Figure 12 is a side view of the connection box 110 with the lid 112 removed. The connection box 110 houses electrical wiring 122 that supplies power to the power connection terminal 121 of the motor 26, and cooling water piping 124 that guides cooling water to the cooling water inlet / outlet 123 of the motor 26. Specifically, the connection box 110 includes a connection box body 111 and a lid 112, and has a D-shape in side view, for example. The connection box body 111 has a mounting plate 125 and a side wall 126. The mounting plate 125 is a plate that is attached to the motor 26. The side wall 126 intersects with the mounting plate 125, for example, at a right angle. The side wall 126 includes a first side wall 126a and a second side wall 126b that is different from the first side wall 126a. The first side wall 126a and the second side wall 126b include flat portions. For example, the first side wall 126a is perpendicular to the X1 and X2 directions (vertical plane). The second side wall 126b, unlike the first side wall 126b, is perpendicular to the Z1 and Z2 directions (horizontal plane). As a result, the first side wall 126a and the second side wall 126b are perpendicular to each other and are different planes. Although this example was explained using the case where the first side wall 126a and the second side wall 126b are perpendicular, the first side wall 126a and the second side wall 126b may intersect at any angle, except that they are on the same plane.

[0058] The lead wires 127, cooling pipes, and signal wires 128 pass through the area where the mounting plate 125 and the motor 26 overlap and are led into the connection box 110. The lead wire 127 is for supplying power to the motor 26. The lead wire 127 is connected to the power connection terminal 121 provided inside the connection box body 111. Then the electrical wire 122 is connected to the power connection terminal 121. The electrical wire 122 is the wiring that carries power and is housed inside the connection box 110. The electrical wire 122 penetrates the first side wall 126a and is connected to the inverter 31. The electrical wire 122 may also penetrate the first side wall 126a via a through terminal.

[0059] The cooling pipe is a pipe that guides the cooling water that cools the stator of the motor 26. The end of the cooling pipe that is drawn into the connection box 110 is an inlet and outlet for the cooling water that cools the motor 26. Hereinafter, this inlet and outlet will be referred to as the cooling water inlet and outlet 123. The cooling water piping 124 is connected to the cooling water inlet and outlet 123. The cooling water piping 124 is housed inside the connection box 110 and guides the cooling water to the cooling water inlet and outlet 123. The cooling water piping 124 penetrates the second side wall 126b and is connected to the third cooling unit 233. As a result, the electrical wiring 122 penetrates the first side wall 126a, and the cooling water piping 124 penetrates the second side wall 126b, which is different from the first side wall 126a. As a result, the electrical wiring 122 and the cooling water piping 124 are introduced into the connection box 110 from different side walls, allowing the connection box 110 to be configured more compactly than if they were introduced into the connection box 110 from the same side wall. The cooling water piping 124 may also pass through the second side wall 126b via a through-pipe 129 that penetrates the second side wall 126b.

[0060] Cooling water flows in from one of the cooling water inlets and outlets 123, is guided by the cooling pipe, circulates around the stator, removes heat from the stator, and flows out from the other of the cooling water inlets and outlets 123. The outflowing cooling water is then guided by the other of the cooling water piping 124 and flows into the third cooling unit 233. The third cooling unit 233 is a heat exchanger that performs heat exchange between the cooling water and the outside air. The cooling water that flows into the third cooling unit 233 is cooled by heat exchange with the outside air and flows out of the third cooling unit 233. The cooling water that flows out of the third cooling unit 233 is guided by the other of the cooling water piping 124 and flows back into one of the cooling water inlets and outlets 123. A water pump (not shown) installed in the middle of the cooling water piping 124 circulates the cooling water. As a result, the heat generated by the motor 26 is dissipated from the third cooling unit 233.

[0061] As explained above, the connection box 110 attached to the motor 26 houses the electrical wiring 122 and the cooling water piping 124. This ensures that the connection points between the electrical wiring 122 and the motor 26, and between the cooling water piping 124 and the motor 26, are pre-installed within the connection box 110. By mounting the motor 26 with the connection box 110 on the UL and UR travel units, the assembly of the electrical wiring 122 and cooling water piping 124 can be simplified. Furthermore, the arrangement of the electrical wiring 122 and cooling water piping 124 on the motor 26 can be made more compact. The same effect can be achieved by providing the connection box 110 described above on the motor 171 that drives the hydraulic pump.

[0062] The connection box 110 may also contain internal signal wiring 128 for a sensor that detects the state of the motor 26. The signal wiring 128 is the wiring for a sensor that detects the state of the motor 26, such as its temperature and rotational speed. The signal wiring 128 passes through the side wall 126 and is connected to, for example, an inverter 31. The inverter 31 operates the motor 26 based on the temperature and rotational speed of the motor 26 indicated by the signal on the signal wiring 128. The signal wiring 128 may also pass through the side wall 126 via a connection connector that passes through the side wall 126. This allows the work vehicle 10 to perform motor control according to the state of the motor 26. A motor 171 equipped with the connection box 110 will have a similar effect.

[0063] The connection box 110 is located on the opposite side of the motor 26's output. Specifically, since the reduction gear 27 is connected to the output shaft of the motor 26, the opposite side of the motor 26's output is the side opposite the motor 26 to the side where the reduction gear 27 is located. As a result, the electrical wiring and cooling water piping housed in the connection box 110 are introduced to the motor 26 from the opposite side of its output. That is, if the electrical wiring and cooling water piping enter from the left side of the work vehicle 10, the output shaft of the motor 26 will output from the right side, and if the electrical wiring and cooling water piping enter from the right side of the work vehicle 10, the output shaft of the motor 26 will output from the left side. As a result, both the connection box 110 and the motor 26 are located on the same axis passing through the motor 26's output shaft, enabling a compact arrangement. The motor 171, which is equipped with the connection box 110, also exhibits a similar effect.

[0064] The motors 26 provided in the left travel unit UL and the right travel unit UR are located closer to the center of the central unit UC than the connection box 110. As a result, the connection box 110 is located further outward from the central unit UC than the motors 26, making it easier for workers to access the connection box 110 and facilitating assembly and maintenance of wiring, etc. Furthermore, at least a portion of the connection box 110 overlaps with the motors 26 in a side view of the central unit UC. This allows the motor 26's lead wiring 127, cooling pipes, and signal wiring 128 to pass through the overlapping portion of the motors 26 and the connection box 110.

[0065] Returning to Figure 11, the connection box 110 may have an opening 114 at its bottom. The opening 114 is for draining water from the cooling box. The opening 114 may be located at the bottom of the lid 112, as shown in Figure 11, or on the bottom surface (Z2 side) of the connection box 110. If there is a coolant leak, the water will drip out of the opening 114, allowing the user to easily detect the leak. Also, since leaked coolant will not accumulate inside the connection box, electrical leakage in the electrical system is suppressed. Furthermore, the connection box 110 may have an opening 115 at its top. Since the opening 115 is located at the top of the connection box 110, if a problem occurs inside the connection box, a fiberscope can be inserted from the top of the connection box 110 without opening the lid. This allows the user to easily inspect the inside. Also, even if there is a leak, air can flow in through the opening 115, allowing the leaked water to be quickly discharged from the opening below. Furthermore, a motor 171 equipped with a connection box 110 also produces a similar effect.

[0066] The embodiments disclosed herein are illustrative in all respects and not restrictive. The scope of the present invention is not limited to the embodiments described above, and includes all modifications within the scope equivalent to the configurations described in the claims. [Explanation of Symbols]

[0067] 9 Exterior components 10 Work vehicles 11. Vehicle body 12, 12LF, 12LR, 12RF, 12RR running gear 13 Displacement actuator 14 Control device 15. Coupling device 16. Battery 16A First Battery, 16L Second Battery 17 Hydraulic unit 19 Work equipment 20. Central frame; 21, 21L, 21R. Side frames. 23 Cooling unit 24 Junction box 24A Main Junction Box 24L, 24R Subjunction Box 25 wheels 26 motors 27 Reducer 28 Power transmission section 29 Steering actuator 31 Inverter 32 Charging ports 33,34 Converter 41 Fixed part 70 Lifting mechanism 73 Hydraulic cylinder 88 Coupling 110 Connection box 111 Connection box body 112 Lid 114 Hole 115 Hole 121 Power connection terminal 122 Electrical wiring 123 Coolant inlet / outlet 124 Cooling water piping 125 Mounting plate 126 Side wall 126a 1st side wall 126b Second side wall 127 Outlet wiring 128 Signal wiring 129 Through-piping 131 Left / Right Actuator 132 Up / Down Actuator 133 Front and rear actuators 171 Motor 205 Case 231 First Cooling Unit 232 Second cooling unit 233 Third cooling unit UC Central Unit, UL, UR Running Unit

Claims

1. The car body and, A running structure that supports the aforementioned vehicle body so that it can move, A motor that drives equipment mounted on the vehicle body or the running structure, A connection box attached to the motor, The connection box contains electrical wiring that supplies power to the power connection terminals of the motor, The connection box contains a cooling water pipe that guides cooling water to the cooling water inlet and outlet of the motor, A work vehicle equipped with the following features.

2. The electrical wiring and the cooling water piping are introduced to the motor from the opposite side of the motor's output. The work vehicle according to claim 1.

3. The motor and the connection box are provided on the travel structure. The motor is located closer to the center of the vehicle body than the connection box. At least a portion of the aforementioned connection box overlaps the motor in a side view of the vehicle body. The work vehicle according to claim 1.

4. The aforementioned connection box has an opening at the bottom, The work vehicle according to claim 1.

5. The connection box has a mounting plate attached to the motor, and a first side wall and a second side wall that intersect with the mounting plate. The electrical wiring penetrates the first side wall, The cooling water piping penetrates the second side wall, which is different from the first side wall. The work vehicle according to claim 1.

6. The aforementioned connection box also contains signal wiring for a sensor that detects the status of the motor. The work vehicle according to claim 1.

Images