Work vehicle

Abstract

The present disclosure relates to a work vehicle. The work vehicle of the present disclosure comprises: an electric motor having an annular flange on a side surface on a first side in an axial direction; a vehicle body having an annular plate to which the electric motor is fixed; and an extension member that connects the flange and the plate. The extension member has a cylindrical boss part, and a flange part that extends radially outward from an axial end of the boss part. The plate is disposed on the first side of the flange in the axial direction. The boss part is inserted from the first side in the axial direction into a through-hole formed in the plate, and is fixed to the flange by a first bolt that is fastened to the flange from the first side in the axial direction. The flange part is disposed on the first side of the plate in the axial direction, and is fixed to the plate by a second bolt that is fastened to the plate from the first side in the axial direction.

Description

Work vehicles

[0001] The present disclosure relates to work vehicles.

[0002] Conventionally, a work vehicle equipped with an electric motor and a battery has been known (see Patent Document 1). The work vehicle disclosed in Patent Document 1 has the battery located inside the hood. The work vehicle disclosed in Patent Document 1 is a tractor.

[0003] Japanese Patent Application Laid-Open No. 2022-060655

[0004] A work vehicle according to one aspect of the present disclosure is a work vehicle comprising an electric motor having an annular flange on a side surface on a first axial side, and a body having an annular plate to which the electric motor is fixed, and further comprising an extension member connecting the flange and the plate, the extension member having a cylindrical boss portion and a flange portion extending radially outward from the axial end of the boss portion, the plate being arranged on the first axial side of the flange, the boss portion being inserted into a through hole formed in the plate from the first axial side and fixed to the flange by a first bolt fastened to the flange from the first axial side, and the flange being arranged on the first axial side of the plate and fixed to the plate by a second bolt fastened to the plate from the first axial side.

[0005] The present disclosure makes it possible to suppress distortion that occurs in an electric motor of a work vehicle equipped with an electric motor when the electric motor is fixed to a chassis.

[0006] FIG. 1 is a perspective view showing an embodiment of a work vehicle according to the present disclosure. FIG. 2 is a front view showing the embodiment of a work vehicle according to the present disclosure. FIG. 3 is a rear view showing the embodiment of a work vehicle according to the present disclosure. FIG. 4 is a right side view showing the embodiment of a work vehicle according to the present disclosure. FIG. 5 is a left side view showing the embodiment of a work vehicle according to the present disclosure. FIG. 6 is a plan view showing the embodiment of a work vehicle according to the present disclosure. FIG. 7 is a bottom view showing the embodiment of a work vehicle according to the present disclosure. FIG. 8 is a perspective view showing a part of the work vehicle according to the present disclosure in an exploded state. FIG. 9 is a left side view of the work vehicle with a part removed. FIG. 10 is a perspective view showing a state in which a motor is mounted on a chassis. FIG. 11 is an overall perspective view showing a state in which the motor is fixed to a plate. FIG. 12 is an exploded perspective view showing a state in which the motor is fixed to a plate. FIG. 13 is a cross-sectional view showing a state in which the motor is fixed to a plate. FIG. 14 is a perspective view showing an extension member as viewed from the boss side.

[0007] <Problem to be Solved by the Invention> In recent years, work vehicles that use a fuel cell module to generate electricity using hydrogen as fuel and that use that electricity to drive an electric motor have been considered. In such work vehicles, the electric motor mounted on the vehicle body is fixed to the chassis that constitutes the vehicle body. However, if the flatness of the mounting surface of the chassis for the electric motor is insufficient, distortion may occur in the electric motor fixed to the mounting surface.

[0008] The present disclosure aims to suppress distortion that occurs in an electric motor fixed to a chassis of a work vehicle equipped with an electric motor.

[0009] Effect of the Invention According to the work vehicle of the present disclosure, in a work vehicle equipped with an electric motor, distortion that occurs in the electric motor when the electric motor is fixed to the chassis can be suppressed.

[0010] <Outline of Embodiments of the Present Disclosure> The following lists and describes outlines of embodiments of the present disclosure. (1) A work vehicle according to this embodiment is a work vehicle including an electric motor having an annular flange on a side surface on a first axial direction side, and a vehicle body having an annular plate to which the electric motor is fixed, and further includes an extension member connecting the flange and the plate. The extension member has a cylindrical boss portion and a flange portion extending radially outward from an axial end portion of the boss portion. The plate is disposed on the first axial side of the flange. The boss portion is inserted into a through-hole formed in the plate from the first axial side and is fixed to the flange by a first bolt fastened to the flange from the first axial side. The flange portion is disposed on the first axial side of the plate and is fixed to the plate by a second bolt fastened to the plate from the first axial side.

[0011] According to the work vehicle of this embodiment, in a work vehicle equipped with an electric motor, distortion that occurs in the electric motor when the electric motor is fixed to the chassis can be suppressed.

[0012] (2) In the work vehicle of this embodiment, it is preferable that the flange has an annular convex portion that protrudes radially inward toward a first axial side, and the boss portion is fixed to the convex portion inserted into the through hole from a second axial side. With a work vehicle configured in this manner, the convex portion can be extended by the boss portion, and a spigot joint structure can be formed by the boss portion, the convex portion, and the through hole. This improves the positioning accuracy of the motor relative to the plate. This also reduces distortion of the motor fixed to the plate.

[0013] (3) In the work vehicle of this embodiment, it is preferable that the extension member includes a first bolt hole through which the first bolt is inserted and a second bolt hole through which the second bolt is inserted, and the first bolt hole is formed radially inward relative to the second bolt hole. A work vehicle configured in this manner can suppress axial misalignment of the electric motor and the extension member, thereby suppressing distortion of the electric motor fixed to the plate.

[0014] (4) In the work vehicle of this embodiment, it is preferable that the outer diameter of the flange of the extension member is larger than the outer diameter of the flange. A work vehicle configured in this manner can suppress axial misalignment between the plate and the extension member, thereby suppressing distortion of the electric motor fixed to the plate.

[0015] (5) It is preferable that the work vehicle according to this embodiment further includes a fuel cell module mounted on the vehicle body, and a hydrogen pipe and a hydrogen tank for supplying hydrogen to the fuel cell module. A work vehicle having such a configuration can suppress distortion of the electric motor fixed to the plate in a work vehicle equipped with an electric motor driven by electricity generated by the fuel cell module.

[0016] <Details of the embodiments of the present disclosure> Hereinafter, the details of the embodiments of the present disclosure will be described with reference to the drawings. Note that at least some of the embodiments described below may be combined in any manner.

[0017] [Overall Configuration of Work Vehicle] Fig. 1 is a perspective view showing one embodiment of a work vehicle according to the present disclosure. Figs. 2 to 7 are a front view, a rear view, a side view (left side view), a side view (right side view), a plan view, and a bottom view of the work vehicle shown in Fig. 1. The work vehicle 10 of this embodiment is a vehicle that can be used for agricultural work, and the work vehicle 10 shown in Fig. 1 is a tractor. The work vehicle is not limited to a tractor. For example, the work vehicle according to the present invention may be an agricultural machine, a construction machine, a utility vehicle, or the like other than a tractor.

[0018] The directions of the work vehicle 10 of the present disclosure are defined below. The direction in which the work vehicle 10 moves forward is defined as "front," the direction in which the work vehicle 10 moves backward is defined as "rear," the left side when facing forward is defined as "left," and the right side when facing forward is defined as "right." The left-right direction perpendicular to the fore-aft direction is defined as the vehicle width direction. The direction perpendicular to both the fore-aft direction and the vehicle width direction (left-right direction) is defined as the up-down direction. The up-down direction is also called the height direction. In each figure, an orthogonal three-dimensional coordinate system is shown, with the forward direction indicated by arrow X1 and the backward direction indicated by arrow X2. The left direction is indicated by arrow Y1 and the right direction is indicated by arrow Y2. The up direction is indicated by arrow Z1 and the down direction is indicated by arrow Z2.

[0019] 1 includes a vehicle body 11, a traveling device 12 that supports the vehicle body 11 so that it can travel, a driver's seat 15, a cabin 16, a tank unit 21 having a tank 13 that stores fuel, and a drive device 14 that is powered by the fuel stored in the tank 13. The fuel is hydrogen, and the tank 13 is a hydrogen tank that stores hydrogen gas. The work vehicle 10 of this embodiment is a fuel cell vehicle (FCV) that travels using electricity generated by a fuel cell (fuel cell module) 24 using hydrogen and oxygen.

[0020] The work vehicle 10 has a drive device 14 that includes a fuel cell 24, a battery unit 30, and an electric motor 31. The battery unit 30 has a battery 300 that stores power generated by the fuel cell 24 and supplies the stored power to the motor 31. The work vehicle 10 has a hydrogen gas piping (hydrogen piping) 22 and a filling unit 25 (see FIG. 3 ). The filling unit 25 has a filling port (receptacle) 26 that connects to a filling nozzle of a hydrogen gas supply device (not shown) that is separate from the work vehicle 10. Hydrogen gas is supplied from the filling port 26 and supplied to the tank 13 through the piping 22 (rear piping 22r). The hydrogen gas in the tank 13 is supplied to the fuel cell 24 through the piping 22 (front piping 22f). The specific configurations of the filling unit 25 and the piping 22 will be described later.

[0021] The work vehicle 10 (see FIG. 1) has a mounting frame 17 and a support structure 37. The mounting frame 17 is a frame for mounting the tank unit 21 (tank 13) on the vehicle body 11. The support structure 37 is a component for supporting the battery unit 30 on the vehicle body 11. The work vehicle 10 (see FIG. 7) has an exhaust path 35. The exhaust path 35 exhausts water or water vapor generated by operation of the fuel cell 24 to the outside. The specific configurations of the mounting frame 17, the support structure 37, and the exhaust path 35 will be described later.

[0022] [Vehicle Body 11] The vehicle body 11 has a chassis 41, a hood 34, a cover 111, and a fender 47 that covers the rear wheels 122 from above. The chassis 41 supports the traveling device 12, the drive device 14, and the cabin 16. Figure 8 is an exploded perspective view of a portion of the work vehicle 10 shown in Figure 1. The chassis 41 is located in the center in the vehicle width direction and has a shape that is long in the vehicle front-to-rear direction. The chassis 41 has a front frame 32 that forms the front portion of the chassis 41, and a gear case 33 that forms the rear portion of the chassis 41. The front frame 32 is formed by combining metal frame materials and the like. The gear case 33 has a metal box body. The gear case 33 is connected to the rear portion of the front frame 32, and the gear case 33 and the front frame 32 form the framework of the vehicle body 11.

[0023] The front frame 32 carries the motor 31. The gear case 33 has therein a power transmission mechanism 333 such as a transmission, a clutch, a differential gear, etc. The power transmission mechanism 333 reduces or increases the rotation speed of the output shaft of the motor 31 and outputs the rotation to the traveling device 12 (one or both of the front wheels 121 and the rear wheels 122).

[0024] The power transmission mechanism 333 outputs a portion of the power of the motor 31 to a PTO shaft 334 (see FIG. 3 ). The PTO shaft 334 is an output shaft provided at the rear of the gear case 33. The work vehicle 10 has a coupling device 43 for coupling another device to the rear of the vehicle body 11. The PTO shaft 334 transmits the power of the motor 31 to the other device coupled to the coupling device 43. The other device is a work device (not shown), also called an implement. The work device is operated by the power of the motor 31. The work device is, for example, a tiller.

[0025] Figure 9 is a left side view of the work vehicle 10, showing the hood 34, cover 111, and a portion of the tank case 211 of the tank unit 21 removed. Starting from the front of the vehicle, the first radiator 48, fuel cell 24, and second radiator 49 are mounted on the chassis 41 in this order. As shown in Figures 4 and 9, the hood 34 and cover 111 cover the mounted components located near the front of the vehicle body 11. The hood 34 covers the fuel cell 24 and first radiator 48 from above and on both sides in the vehicle width direction. The cover 111 covers the second radiator 49 located behind the fuel cell 24 from above and on both sides in the vehicle width direction.

[0026] The upper surface 48a of the first radiator 48 is lower than the upper surface 24a of the fuel cell 24. The upper surface 24a of the fuel cell 24 is lower than the upper surface 49a of the second radiator 49. The upper surface 111a of the cover 111 is higher than the upper surface 34a of the hood 34, but lower than the upper end of the steering wheel 151 that is operated by an operator sitting in the driver's seat 15 to steer the vehicle. The upper surface 34a of the hood 34 becomes lower toward the front. This makes it less likely that the field of vision of the operator sitting in the driver's seat 15 will be obstructed.

[0027] [Driver's Seat 15 and Cabin 16] The driver's seat 15 and the cabin 16 are provided on the chassis 41 at a rearward position (see FIG. 1). The cabin 16 has the driver's seat 15 inside. The cabin 16 has front pillars 162 located in front of the driver's seat 15, rear pillars 163 located behind the driver's seat 15, and a roof 164 located above the driver's seat 15. The front pillars 162 are provided on the left front and right front of the driver's seat 15. The rear pillars 163 are provided on the left rear and right rear of the driver's seat 15. The roof 164 is supported by the front pillars 162 and rear pillars 163.

[0028] The cabin 16 has a windshield 165 located in front of the driver's seat 15. The windshield 165 is provided between the left and right front pillars 162. The cabin 16 has openable and closable doors 166 on both sides in the vehicle width direction. The doors 166 are provided between the front pillars 162 and the rear pillars 163.

[0029] A step 167 is provided on one side (left side) of the cabin 16 in the vehicle width direction (see FIG. 5). The step 167 is a member on which an operator places their feet when getting in and out of the cabin 16. A cover 111 and a bonnet 34 are provided in front of the cabin 16. As shown in FIGS. 2 and 6, the dimensions of the cover 111 and the bonnet 34 in the vehicle width direction are each smaller than the dimension of the cabin 16 in the vehicle width direction. The dimension of the bonnet 34 in the vehicle width direction is smaller than the dimension of the cover 111 in the vehicle width direction.

[0030] The work vehicle 10 of this embodiment has a cabin 16, but it does not have to have the cabin 16. The work vehicle 10 may have a canopy or ropes instead of the cabin 16. If the work vehicle 10 does not have a cabin 16, the tank unit 21 is supported by the mounting frame 17 and is located above the driver's seat 15.

[0031] [Traveling device 12] The traveling device 12 has front wheels 121 and rear wheels 122 (see FIG. 6). The front wheels 121 are provided on the left and right sides of the front part of the vehicle body 11. The rear wheels 122 are provided on the left and right sides of the rear part of the vehicle body 11. The maximum dimension in the vehicle width direction of the left and right rear wheels 122 is greater than the maximum dimension in the vehicle width direction of the left and right front wheels 121. The maximum dimension in the vehicle width direction of the left and right rear wheels 122 is the maximum vehicle width dimension of the work vehicle 10. One or both of the front wheels 121 and the rear wheels 122 rotate by the power of the motor 31. One or both of the front wheels 121 and the rear wheels 122 (drive wheels) that rotate by the power of the motor 31 may be crawlers (crawlers).

[0032] [Drive unit 14] As described above, the drive unit 14 is configured to include the fuel cell 24, the battery unit 30, and the motor 31. The fuel cell 24 is located on the chassis 41 near the front of the vehicle body 11 (see FIG. 9). The motor 31 is located behind the fuel cell 24 (see FIG. 8). The battery unit 30 is located near the outer side of the vehicle body 11 in the vehicle width direction (see FIG. 1). The battery unit 30 is attached to the chassis 41 by a support structure 37.

[0033] The fuel cell 24 generates electricity using hydrogen gas to obtain the power to rotate the motor 31. The fuel cell 24 (see FIG. 9 ) has a battery casing 241 in the shape of a substantially rectangular box and a fuel cell stack 242 provided inside the battery casing 241. The fuel cell stack 242 has a plurality of battery cells. Each battery cell has a positive electrode and a negative electrode. A plurality of unit cells are stacked. The power generated by each battery cell is collected and output to the battery unit 30.

[0034] The motor 31 has a rotating rotor and a stator having a plurality of coils. The output shaft of the motor 31 is connected to a power transmission mechanism 333 in a gear case 33 (see FIG. 8). The motor 31 is located behind the fuel cell 24 and below the second radiator 49.

[0035] [Tank Unit 21] The tank unit 21 (see FIG. 9 ) has a tank 13 and a tank case 211 that houses the tank 13. The tank 13 is a substantially cylindrical high-pressure vessel. The tank 13 is made of fiber-reinforced resin reinforced with carbon fiber or glass fiber, or the like. In this embodiment, three tanks 13 are fixed to the tank case 211 with the axial direction of their cylindrical portions parallel to the vehicle width direction. The number of tanks 13 is not limited to three.

[0036] The tank case 211 is a box that can accommodate one or more tanks 13. The tank case 211 has a box shape that completely covers the tanks 13 that it accommodates. The tank case 211 has an opening / closing door 213 (see FIG. 1 ) on one or both sides in the vehicle width direction, and is open in the vehicle width direction. The tank case 211 is installed above the roof 164 with a gap between it and the roof 164 in the vertical direction. The tank case 211 is fixed to the upper frame portion 171 of the mounting frame 17. The tank case 211 is made of metal such as aluminum or steel, and protects the tanks 13 from external thermal and physical influences.

[0037] The tank 13 is located above the cabin 16 (driver's seat 15). This allows for a high degree of freedom in the placement of the fuel cell 24, filling section 25, motor 31, and battery unit 30 in the vehicle body 11. When a conventional work vehicle with an internal combustion engine is modified to have a work vehicle 10 equipped with a fuel cell 24 and motor 31 as in this embodiment, there is no need to significantly change the placement and configuration of the various devices.

[0038] The tank 13 is connected to a rear pipe 22r and a front pipe 22f via a valve unit 212 (see FIG. 9). The rear pipe 22r (see FIG. 3) is a gas inlet pipe connecting the hydrogen gas fill port 26 and the valve unit 212, and guides hydrogen gas introduced into the fill port 26 to the tank 13. The front pipe 22f (see FIG. 2) is a gas outlet pipe connecting the fuel cell 24 and the valve unit 212, and guides hydrogen gas stored in the tank 13 to the fuel cell 24. The tank 13 stores hydrogen gas introduced into the fill port 26 from outside the vehicle and supplies it to the fuel cell 24. The valve unit 212 has an on-off valve, a pressure reducing valve, etc., and adjusts the hydrogen gas stored in the tank 13 to a predetermined flow rate and guides it to the fuel cell 24 through the front pipe 22f.

[0039] [Mounting Frame 17] The mounting frame 17 (see FIG. 1) is a frame structure for mounting the tank 13 on the vehicle body 11. The mounting frame 17 of this embodiment has an upper frame portion 171 that supports the tank 13, and a first front frame portion 172, a second front frame portion 175, and a rear frame portion 173 that serve as frames for supporting the upper frame portion 171. A tank case 211 is attached to the upper frame portion 171. In other words, the upper frame portion 171 supports the tank 13 via the tank case 211. The specific configuration of the mounting frame 17 will be described later.

[0040] A filling section 25 (see FIG. 3) is provided on the rear frame section 173. The filling section 25 has a filling port 26 to which a gas filling nozzle of a hydrogen gas supply device (not shown) installed outside the vehicle is connected when filling the tank 13 with hydrogen gas.

[0041] [Radiator] The work vehicle 10 (see FIGS. 4 and 5) has a cooling system that uses coolant to cool the fuel cell 24, motor 31, boost circuit 80, inverter 81, DC / DC converters 82, 83, etc. As part of the cooling system, the work vehicle 10 has a first radiator 48 and a second radiator 49. As shown in FIG. 9, the first radiator 48 is located in front of the fuel cell 24, and the second radiator 49 is located behind the fuel cell 24.

[0042] The first radiator 48 is a radiator for cooling devices other than the fuel cell 24. The second radiator 49 is a radiator for cooling the fuel cell 24. The first radiator 48 is connected to electrical components (heat-generating components) that require cooling, such as the motor 31, the boost circuit 80, the inverter 81, and the DC / DC converters 82 and 83, via a first cooling flow path (not shown) having a circulation pump. The first radiator 48 cools the coolant supplied through the first cooling flow path by heat exchange with external air. The second radiator 49 is connected to the fuel cell 24 via a second cooling flow path (not shown) having a circulation pump. The second radiator 49 cools the coolant supplied through the second cooling flow path by heat exchange with external air.

[0043] The first radiator 48 has a first fan 481. The second radiator 49 has a second fan 491. The first fan 481 and the second fan 491 rotate to pass air through the first radiator 48 and the second radiator 49, facilitating heat exchange with the coolant.

[0044] [Battery Unit 30] The battery unit 30 stores power to be supplied to the motor 31. The battery unit 30 (see FIG. 9 ) has a battery (battery pack) 300 and a housing 307 that houses the battery 300. The battery 300 temporarily stores the power generated by the fuel cell 24 and outputs the stored power to electrical devices such as the motor 31. The battery 300 is composed of multiple battery cells. The battery 300 is a charge-discharge type secondary battery such as a lithium-ion battery or a lead-acid battery.

[0045] [Electrical System] The work vehicle 10 has a junction box 75. The junction box 75 is an electrical connection box for relaying and distributing the power output from the battery unit 30. The fuel cell 24 is connected to an inverter 81 (see FIG. 5 ) via a boost circuit. The battery unit 30 is connected to the inverter 81 through the junction box 75. The inverter 81 is electrically connected to the motor 31. The inverter 81 converts the DC power output from the boost circuit into three-phase AC power and outputs it to the motor 31.

[0046] The work vehicle 10 has low-voltage electrical equipment that operates at a lower voltage than the motor 31. Power that has been stepped down by a step-down circuit is supplied to the low-voltage electrical equipment through a junction box 75. In the work vehicle 10 of this embodiment, the low-voltage electrical equipment is the battery unit 30, radiators 48, 49, and air conditioning unit 74. The work vehicle 10 has a first DC / DC converter 82 and a second DC / DC converter 83 as the step-down circuit.

[0047] [Regarding motor placement] Figure 10 is a perspective view showing the state in which the motor is mounted on the chassis. As shown in Figure 10, in the work vehicle 10 of the present disclosure, the front frame 32, which is part of the chassis 41, is provided with a plate 410 at its rear end for fixing the rear side of the motor 31. The front frame 32 is provided with an intermediate plate 420 at its middle portion for fixing the front side of the motor 31. In the work vehicle 10, the motor 31 is disposed between the plate 410 and the intermediate plate 420. The motor 31 is mounted on the front frame 32 with its front side fixed to the intermediate plate 420 and its front side fixed to the plate 410.

[0048] [Regarding the Fixed State of the Motor] FIG. 11 is an overall perspective view showing the fixed state of the motor relative to the plate. FIG. 12 is an exploded perspective view showing the fixed state of the motor relative to the plate. FIG. 13 is a cross-sectional view showing the fixed state of the motor relative to the plate. As shown in FIGS. 11 to 13, in the work vehicle 10 of the present disclosure, the motor 31 is fixed to the plate 410 via an extension member 320. In the following description, the center of the rotational shaft of the motor 31 will also be referred to as the central axis C (see FIG. 13). In the following description, with the direction of the central axis C of the motor 31 as the reference, the rear side of the work vehicle 10 (the direction of arrow X2) will also be referred to as the first axial side, and the front side of the work vehicle 10 (the direction of arrow X1) will also be referred to as the second axial side. In the following description, the direction perpendicular to the central axis C will also be referred to as the radial direction.

[0049] [Regarding the Motor] As shown in FIG. 12 , the motor 31 includes a cylindrical case 310 and an annular flange 311 fixed to a first axial end of the case 310. The flange 311 includes a mounting surface 312 that contacts the plate 410 and a protrusion 314 that protrudes radially inward from the mounting surface 312 toward the first axial end. The flange 311 further includes a shaft hole 315 formed radially inward of the protrusion 314. The shaft hole 315 is coaxial with the central axis C and receives a shaft (not shown) that transmits the output of the motor 31 to the power transmission mechanism 333. The motor 31 includes a plurality of (six in this embodiment) bolt holes 313 in the protrusion 314 for fixing the extension member 320 (specifically, the boss portion 321). The bolt hole 313 has a female thread into which a first bolt 431 is threaded.

[0050] [Regarding the Plate] As shown in FIG. 12 , the plate 410 includes an annular plate body 411. The plate body 411 includes a through-hole 412 formed radially inward. The plate 410 is disposed on a first axial side of the flange 311. The through-hole 412 is formed coaxially with the central axis C, and a shaft (not shown) that transmits the output of the motor 31 to the power transmission mechanism 333 is passed through the through-hole 412. The plate 410 is disposed adjacent to the first axial side of the motor 31, with the protrusion 314 inserted into the through-hole 412 and a side surface 414 on the second axial side of the plate body 411 in contact with the mounting surface 312. The plate 410 includes a plurality of bolt holes 413 (four in this embodiment) for fixing the extension member 320. The bolt holes 413 have female threads into which second bolts 432 are threaded.

[0051] [Regarding the Extension Member] Fig. 14 is a perspective view showing the extension member as seen from the boss side. As shown in Figs. 12 and 14, the extension member 320 includes a cylindrical boss portion 321 and a flange portion 322 extending radially outward from the end of the boss portion 321. Note that, in the extension member 320 of this embodiment, the boss portion 321 and the flange portion 322 are configured as separate bodies, but the boss portion 321 and the flange portion 322 may also be configured as a single body.

[0052] In the work vehicle 10, the extension member 320 is used with the boss portion 321 facing the second axial side and the flange portion 322 facing the first axial side. The extension member 320 includes a through hole 323 formed radially inward of the boss portion 321 and the flange portion 322. The extension member 320 is arranged so that the flange portion 322 contacts the first axial side of the plate 410 with the boss portion 321 inserted through the through hole 412 and the front end face of the boss portion 321 in contact with the protrusion 314. The extension member 320 includes a plurality of (six in this embodiment) first bolt holes 324 for fixing the boss portion 321 to the flange 311. The first bolt holes 324 are holes that axially penetrate the boss portion 321 and the flange portion 322, and first bolts 431 are inserted through the first bolt holes 324. The extension member 320 has a plurality of (four in this embodiment) second bolt holes 325 for fixing the flange 322 to the plate 410. The second bolt holes 325 are holes that axially pass through the flange 322, and second bolts 432 are inserted through the second bolt holes 325.

[0053] In the extension member 320, the plurality of first bolt holes 324 are formed radially inward compared to the plurality of second bolt holes 325. The boss portion 321 of the extension member 320 is fixed to the motor 31 (flange 311) at a position closer to the central axis C of the motor 31, thereby making it possible to suppress axial misalignment between the extension member 320 and the motor 31. With a work vehicle 10 configured in this manner, axial misalignment between the motor 31 and the extension member 320 can be suppressed, thereby suppressing distortion of the motor 31 fixed to the plate 410.

[0054] The outer diameter of the boss portion 321 is approximately the same as the inner diameter of the through-hole 412 and the outer diameter of the protrusion 314. In the work vehicle 10 of the present disclosure, the outer diameter dimension A of the flange portion 322 is larger than the outer diameter dimension B of the flange 311 (see FIG. 13 ). The extension member 320 has the flange portion 322 fixed to the plate 410 (plate main body 411) at a position away from the central axis C of the motor 31, which makes it possible to increase the contact area between the flange portion 322 and the plate 410, thereby suppressing axial misalignment between the extension member 320 and the plate 410. With this configuration, the work vehicle 10 of the present disclosure can suppress axial misalignment between the plate 410 and the extension member 320, thereby suppressing distortion of the motor 31 fixed to the plate 410.

[0055] 14 , the extension member 320 further includes an annular protrusion 326 at the end on the second axial side of the boss portion 321. The protrusion 326 is inserted into the shaft hole 315 of the flange 311. By inserting the protrusion 326 into the shaft hole 315, the extension member 320 is positioned with greater precision relative to the motor 31 in the radial direction.

[0056] 11 to 13 , the boss portion 321 of the extension member 320 is fixed to the convex portion 314 of the flange 311 by threading a first bolt 431 inserted into the first bolt hole 324 from the first axial side into the bolt hole 313. The flange portion 322 of the extension member 320 is fixed to the plate 410 (plate main body 411) by threading a second bolt 432 inserted into the second bolt hole 325 from the first axial side into the bolt hole 413. In other words, the boss portion 321 is fixed to the flange 311 (convex portion 314) by inserting the first bolt 431 into the through hole 412 formed in the plate 410 from the first axial side and fastening it to the flange 311 from the first axial side. The flange 322 is disposed on a first axial side of the plate 410 and is fixed to the plate 410 by a second bolt 432 that is fastened to the plate 410 from the first axial side.

[0057] In the work vehicle 10 of the present disclosure, the flange 311 has an annular protrusion 314 that protrudes radially inward toward a first axial side, and a boss portion 321 is fixed to the protrusion 314 that is inserted into the through-hole 412 from a second axial side. The extension member 320 is fixed to an end face on the first axial side of the protrusion 314 and to a side surface 415 on the first axial side of the plate 410. This configuration makes it possible to suppress the force generated when the motor 31 is fixed to the plate 410, specifically, the force that pulls the flange 311 in the axial direction. This makes it possible to suppress distortion of the motor 31 fixed to the plate 410.

[0058] Because the plate 410 is a part of the chassis 41 and a relatively large component, it is difficult to precisely process the side surfaces 414, 415 of the plate 410 to remove welding distortion, etc. If the flange 311 were directly fixed to such a side surface 414, distortion of the side surface 414 would cause distortion in the flange 311. The extension member 320 is a smaller component than the plate 410, and can be easily processed with high precision to remove distortion, etc., and the flatness of the end surface can be easily ensured. Therefore, when the flange 311 and the plate 410 are connected via the extension member 320, the distortion of the plate 410 can be prevented from affecting the flange 311, thereby suppressing distortion that occurs in the flange 311 when the motor 31 is fixed to the plate 410.

[0059] [Regarding the spigot joint structure] The flange 311 and the plate 410 form a spigot joint structure by inserting the protrusion 314 into the through hole 412. The "spigot joint structure" here refers to a structure in which a recess formed on one component is fitted with a protrusion formed on the other component, enabling the components to be firmly combined while being positioned. In the work vehicle 10 disclosed herein, by connecting the boss portion 321 to the protrusion 314, the same effect as extending the protrusion 314 toward the first axial side can be achieved. In the work vehicle 10 disclosed herein, by using the extension member 320, the motor 31, the extension member 320, and the plate 410 can form a spigot joint structure. This can reliably suppress axial misalignment of the motor 31 and the plate 410 and further improve the positioning accuracy of the motor 31 and the plate 410. Furthermore, in the work vehicle 10 disclosed herein, the extension member 320 can axially extend the "spigot joint structure" formed by the through hole 412 and the protrusion 314. For example, if the motor and the plate were fixed directly, it would be necessary to position relatively large parts relative to each other, making the task of attaching the motor to the plate laborious. The work vehicle 10 of the present disclosure can connect the motor 31 and the plate 410 by adjusting the position of the relatively small extension member 320 (without the need to adjust the positions of the motor 31 and the plate 410). Therefore, the work vehicle 10 of the present disclosure can easily attach the motor 31 to the plate 410 by using the extension member 320 to axially extend the "spigot joint structure" formed by the through hole 412 and the protrusion 314.

[0060] The motor 31 shown in this embodiment employs a water-cooling system in which a flow path (jacket) is formed inside the thickness of the case 310. With this type of motor 31, if distortion occurs in the flange 311 when the motor 31 is fixed to the plate 410, a gap will form between the case 310 and the flange 311, and fluid passing through the jacket may leak from the gap. By fixing the motor 31 to the plate 410 via the extension member 320, the work vehicle 10 of the present disclosure can suppress distortion occurring in the flange 311, thereby suppressing leakage of fluid passing through the jacket.

[0061] The above-described embodiments are illustrative in all respects and are not limiting. The scope of the present invention is defined by the claims rather than the above-described embodiments, and includes all modifications within the scope equivalent to the configurations described in the claims.

[0062] REFERENCE SIGNS LIST 10 Work vehicle 11 Vehicle body 13 Tank (hydrogen tank) 22 Pipe (hydrogen pipe) 24 Fuel cell (fuel cell module) 31 Motor (electric motor) 311 Flange 314 Convex portion 320 Extension member 321 Boss portion 322 Flange portion 324 First bolt hole 325 Second bolt hole 410 Plate 412 Through hole 431 First bolt 432 Second bolt A Outer diameter dimension (of flange) B Outer diameter dimension (of flange)

Claims

1. A work vehicle comprising: an electric motor having an annular flange on a side surface on a first axial direction; and a vehicle body having an annular plate to which the electric motor is fixed, further comprising an extension member connecting the flange and the plate, the extension member having a cylindrical boss portion and a flange portion extending radially outward from an axial end portion of the boss portion, the plate being arranged on the first axial side of the flange, the boss portion being inserted into a through hole formed in the plate from the first axial side and fixed to the flange by a first bolt fastened to the flange from the first axial side, and the flange portion being arranged on the first axial side of the plate and fixed to the plate by a second bolt fastened to the plate from the first axial side.

2. A work vehicle as described in claim 1, wherein the flange has an annular convex portion protruding radially inwardly toward a first axial side, and the boss portion is fixed to the convex portion inserted into the through hole from a second axial side.

3. A work vehicle as described in claim 1 or claim 2, wherein the extension member is provided with a first bolt hole through which the first bolt is inserted and a second bolt hole through which the second bolt is inserted, and the first bolt hole is formed radially inward compared to the second bolt hole.

4. A work vehicle as described in claim 1 or claim 2, wherein the extension member has an outer diameter dimension of the flange portion that is larger than the outer diameter dimension of the flange.

5. The work vehicle according to claim 1 or 2, further comprising: a fuel cell module mounted on the vehicle body; and a hydrogen pipe and a hydrogen tank for supplying hydrogen to the fuel cell module.

Images