Work vehicle

By positioning inverter devices on either side of the vehicle width below the floor, the work vehicle addresses maintenance challenges with increased ground clearance and reduced size, ensuring efficient power conversion and easy access for maintenance.

JP7770255B2Active Publication Date: 2025-11-14KUBOTA CORP
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Patent Information

Application Number
JP2022090762
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2022-06-03
Publication Date
2025-11-14
Estimated Expiration
2042-06-03

AI Technical Summary

Technical Problem

Existing work vehicles face challenges in maintaining inverter devices due to their large size and the need for easy access, which is hindered by limited ground clearance and complex layout configurations.

Method used

The work vehicle design incorporates two inverter devices positioned on either side of the vehicle width, below the floor, allowing for increased ground clearance without raising the floor height, facilitating easy maintenance from the lateral side, and utilizing two electric motors connected to these inverter devices for efficient power conversion.

Benefits of technology

This configuration enables easier maintenance of inverter devices by increasing ground clearance and reducing the overall size, while maintaining power conversion functionality, and allows for flexible layout options.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

To enable an inverter device to be provided in a state that enables easy maintenance and increase a minimum ground clearance of the inverter device without increasing a ground clearance of a floor part of an operation part in a service vehicle including an electric motor connected to a travel power transmission device which transmits power to rear travel devices.SOLUTION: A service vehicle includes two inverter devices 21A, 21B connected to electric motors 17, 18. One 21A of the inverter devices is provided between front wheels and rear travel devices and in a portion located at one side as seen in a vehicle body lateral width direction relative to a travel power transmission device 15 of a space located below a floor part 11 of an operation part. The other inverter device 21B is provided between the front wheels and the rear travel devices and in a portion located at the other side as seen in the vehicle body lateral width direction relative to the travel power transmission device 15 of the space located below the floor part 11 of the operation part.SELECTED DRAWING: Figure 4
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Description

[Technical Field]

[0001] The present invention relates to a work vehicle having a running body supported by front wheels and a rear running device, and the running body is provided with a driver's section having a floor section for riding on. [Background technology]

[0002] As shown in Patent Document 1, some of the above-mentioned work vehicles are equipped with a traveling power transmission device (continuously variable transmission, forward / rear switching device, gear transmission device) that transmits power to the rear traveling device (rear wheels), and an electric motor (motor generator) connected to the traveling power transmission device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-65349 Summary of the Invention [Problem to be solved by the invention]

[0004] The above-mentioned work vehicles generally include an inverter device connected to the electric motor, and therefore it is desirable that the inverter device be easy to maintain.

[0005] The present invention provides a work vehicle in which the minimum ground clearance of an inverter device is increased without increasing the height of the floor above the ground, and the inverter device can be installed in a state where maintenance is easy. [Means for solving the problem]

[0006] The work vehicle according to the present invention comprises: A running body supported by front wheels and a rear running device is provided, The traveling vehicle body is provided with a driver's section having a floor section for riding, a traveling power transmission device that transmits power to the rear traveling device, and an electric motor connected to the traveling power transmission device, and is provided with two inverter devices connected to the electric motor, one of the two inverter devices is provided in a space between the front wheels and the rear traveling device and located below the floor, at a location located on one side of the traveling power transmission device in the vehicle width direction, and the other of the two inverter devices is provided in a space between the front wheels and the rear traveling device and located below the floor, at a location located on the other side of the traveling power transmission device in the vehicle width direction. In a plan view, the two inverter devices overlap with the floor portion, and a step for getting on and off is provided on the lateral outer side of the driving section, and the inverter device is provided in the center of the vehicle width direction from the step for getting on and off. are.

[0007] According to this configuration, the maintenance for the inverter device is passed from the lateral outer side of the vehicle body between the front wheels and the rear traveling device. Tena Since two inverter devices are used, the vertical length of each inverter device can be shortened while still providing the necessary power conversion function compared to when a single inverter device is used. Since the inverter devices with a short vertical length are distributed to both sides of the traveling power transmission device and installed below the floor, the minimum ground clearance of each inverter device can be increased without increasing the ground clearance of the floor compared to when a single inverter device with a long vertical length is installed below the floor. In other words, the minimum ground clearance of the inverter device can be increased without increasing the height of the floor portion above the ground, and the inverter device can be installed in a state where maintenance is easy. In addition, inverter devices used in work vehicles tend to be large in size because they can handle large amounts of power, but dividing them into two can sometimes result in a smaller overall size. This also allows for greater freedom in layout.

[0008] In the present invention, it is preferable that the traveling power transmission device includes a transmission case and a transmission provided inside the transmission case.

[0009] According to this configuration, hmmThe drive speed of the rear traveling device can be changed by the transmission, so that even when different tasks are being performed, the vehicle can travel at a speed appropriate to the task.

[0010] In the present invention, It is preferable that two electric motors are provided, one of the two electric motors is connected to one of the two inverter devices, and the other of the two electric motors is connected to the other of the two inverter devices.

[0011] According to this configuration, it is easy to prevent the connection structure connecting one electric motor to one inverter device and the connection structure connecting the other electric motor to the other inverter device from intersecting.

[0012] In the present invention, It is preferable that two electric motors are provided, and that the two electric motors and the two inverter devices are provided inside the transmission case with the two electric motors and the two inverter devices positioned at the same position in the fore-and-aft direction of the vehicle body.

[0013] According to this configuration, the inverter device is located near the electric motor, making it easy to connect the electric motor and the inverter device.

[0014] In the present invention, The two electric motors are preferably arranged side by side in a direction along the width direction of the vehicle body.

[0015] According to this configuration, the inverter devices located on both sides of the transmission case are located close to the electric motor, making it easy to connect the electric motor and the inverter devices.

[0016] In the present invention, It is preferable that a first support member is provided between a first inverter device of the two inverter devices and the transmission case, supporting the first inverter device, and a second support member is provided between a second inverter device of the two inverter devices and the transmission case, supporting the second inverter device.

[0017] According to this configuration, the first inverter device is supported by the highly rigid transmission case via the first support member, and the second inverter device is supported via the second support member, so that the first inverter device and the second inverter device can be firmly supported so as to be less likely to rattle. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 2 is a side view showing the left side of the tractor. [Figure 2] FIG. 2 is a side view showing the right side of the tractor. [Figure 3] FIG. 2 is a schematic diagram of a driving power transmission device. [Figure 4] FIG. 2 is a front view showing the installation of the inverter device. [Figure 5] FIG. 2 is a side view showing the installation of the inverter device on the left side of the vehicle body. [Figure 6] FIG. 2 is a side view showing the installation of the inverter device on the right side of the vehicle body. DETAILED DESCRIPTION OF THE INVENTION

[0019] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described with reference to the accompanying drawings. In the following description, with respect to the traveling body of a tractor (an example of a "work vehicle"), the direction of arrow F shown in Figures 1, 2, etc. will be referred to as the "front of the body," the direction of arrow B shown in Figures 1, 2, etc. will be referred to as the "rear of the body," the direction of arrow U shown in Figures 1, 2, etc. will be referred to as the "upper side of the body," and the direction of arrow D shown in Figures 1, 2, etc. will be referred to as the "lower side of the body." The direction of L shown on the front side of Figure 1, the back side of Figure 2, and Figure 4 will be referred to as the "left side of the body," and the direction of R shown on the back side of Figure 1, the front side of Figure 2, and Figure 4 will be referred to as the "right side of the body." The left-right direction of the body is the width direction of the body.

[0020] [Overall configuration of the tractor] As shown in FIGS. 1 and 2 , the tractor includes a traveling body 3 supported by a pair of left and right drivable front wheels 1 and a pair of left and right drivable rear wheels 2 serving as rear traveling devices. The traveling body 3 has a body frame 4 that is composed of an engine 5 provided at the front of the traveling body 3, a transmission case 13 whose front portion is connected to the rear of the engine 5, and a front frame 14 connected to the bottom of the engine 5. A driving unit 6 having the engine 5 is provided at the front of the traveling body 3. A driver's unit 9 is provided at the rear of the traveling body 3. A link mechanism (not shown) that connects a work implement such as a rotary tiller (not shown) so that it can be raised and lowered is provided at the rear of the transmission case 13, and a power takeoff shaft 12 that extracts and transmits power from the engine 5 to the connected work implement. In this embodiment, the rear wheels 2 serve as rear traveling devices, but a mini-crawler type traveling device can also be used as the rear traveling device.

[0021] [Operation department] 1 and 2, the driver's section 9 is provided with a driver's seat 7, a floor section 11 (see FIG. 4) provided in front of and below the driver's seat 7 for boarding, a steering wheel 8 for steering the front wheels 1, and a driver's cabin 10 that covers the boarding space. The floor section 11 is supported by the driver's cabin 10. As shown in FIG. 4, an upwardly extending bulge 11a is provided in the center of the floor section 11 in the vehicle width direction (a portion located above the transmission case 13).

[0022] The driver's cabin 10 is supported on the vehicle body frame 4 via front buffer materials 10a (see FIGS. 1 and 2) and rear buffer materials 10b (see FIGS. 1 and 2), which reduce the transmission of vibrations caused by driving and the like to the driver's cabin 10. Specifically, the front left and right locations of the lower frame 10c of the driver's cabin 10 are connected to the front of the transmission case 13 via the front buffer materials 10a, and the rear left and right locations of the lower frame 10c are connected to the rear of the transmission case 13 via the rear buffer materials 10b.

[0023] 1 and 2, two upper and lower steps 50 for boarding and alighting used for getting on and off the driver's section 9 are provided on each of the outer right and left sides of the driver's section 9. In a side view of the vehicle body, the upper step 50a of the two upper and lower steps 50 is located below the boarding / alighting entrance 9a of the driver's section 9, and the lower step 50b of the two upper and lower steps 50 is offset toward the front of the vehicle body with respect to the upper step 50a.

[0024] [Motor unit] 1 and 2, the motor section 6 has an engine compartment 52 formed by an engine bonnet 51. The engine 5 is mounted at the rear of the engine compartment 52. An exhaust gas treatment device 53 that purifies the exhaust gas from the engine 5 is mounted above the rear of the engine 5. In the exhaust gas treatment device 53, urea water is injected as a reducing agent supplied from a reducing agent tank (not shown) into the exhaust gas introduced from the engine 5, causing hydrolysis, thereby purifying the exhaust gas by reducing nitrogen oxides contained in the exhaust gas. The purified exhaust gas is discharged from an exhaust pipe 53a connected to the exhaust gas treatment device 53.

[0025] [Traveling power transmission device] 1 and 2, a driving power transmission device 15 that transmits power from the engine 5 to the front wheels 1 and rear wheels 2 includes a transmission case 13 whose front portion is connected to the rear portion of the engine 5. The transmission case 13 is aligned with the engine 5 in the longitudinal direction of the vehicle body and extends in the longitudinal direction of the vehicle body at the center in the lateral width direction of the vehicle body. The engine 5 and the transmission case 13 are connected by connecting a flywheel housing (not shown) that is provided at the rear of the engine 5 and that houses a flywheel 5a (see FIG. 3) to a clutch housing (not shown) that is provided at the front of the transmission case 13.

[0026] As shown in FIG. 3, the transmission case 13 houses a hybrid transmission 16 as a transmission that changes the speed of power from the engine 5 and outputs it to the front wheels 1 and the rear wheels 2.

[0027] [Hybrid Transmission] 3, the hybrid transmission 16 is provided with an input shaft 23 that is provided in the front part of the transmission case 13 and receives power from the output shaft 5b of the engine 5, an electric transmission unit 16A that is located adjacent to the rear of the engine 5, and a gear transmission unit 16B that is located rearward of the electric transmission unit 16A. The axis of the input shaft 23 and the axis of the output shaft 5b are aligned on the same axis.

[0028] As shown in FIG. 3 , the electric transmission section 16A is housed in an electric transmission chamber 28 formed in the front part of the transmission case 13. The gear transmission section 16B is housed in a gear transmission chamber 29 formed in the rear part of the transmission case 13. The electric transmission chamber 28 is formed by the peripheral wall of the transmission case 13, a front wall 13a provided inside the front end of the transmission case 13, and a blocking wall 13b provided inside the middle part of the transmission case 13. The gear transmission chamber 29 is formed by the peripheral wall of the transmission case 13, a rear wall 13c located at the rear end of the transmission case 13, and the blocking wall 13b. The electric transmission chamber 28 and the gear transmission chamber 29 are adjacent to each other with the blocking wall 13b sandwiched between them. The electric transmission chamber 28 and the gear transmission chamber 29 are separated from each other by the blocking wall 13b to prevent communication between them.

[0029] [Electric Transmission] As shown in FIG. 3 , the electric transmission unit 16A is provided between the engine 5 and the gear transmission unit 16B. The electric transmission unit 16A is equipped with motor generators 17, 18 as two electric motors. In this embodiment, as shown in FIG. 4 , the two motor generators 17, 18 are arranged in the vehicle width direction with the rotational axes of each motor generator 17, 18 aligned along the vehicle front-rear direction and the rotational axes of the two motor generators 17, 18 aligned along the vehicle width direction. Compared to when the two motor generators are aligned along the vehicle front-rear direction, motor generators having a longer length along the vehicle front-rear direction can be used as each motor generator 17, 18. In this embodiment, the two motor generators 17, 18 have the same outer diameter. In this embodiment, the two motor generators 17, 18 are aligned along the vehicle width direction. However, they may also be aligned along the vehicle up-down direction or slanted downward to the left or right as viewed in the vehicle front-rear direction.

[0030] [Gear Transmission Section] 3, the gear transmission unit 16B is provided on the opposite side of the electric transmission unit 16A from the side on which the engine 5 is located. The gear transmission unit 16B is located adjacent to and behind the electric transmission unit 16A.

[0031] 3, the gear transmission unit 16B has a gear transmission mechanism 30. The gear transmission mechanism 30 is provided with a transmission mechanism input shaft 99, a gear transmission mechanism 98, a low-speed planetary transmission unit 100, a low-speed clutch 100C, a high-speed planetary transmission unit 110, a high-speed clutch 110C, a forward / reverse switching device 25, an auxiliary transmission device 26, a rear wheel differential mechanism 19, a front wheel transmission device 20, and a gear interlocking mechanism 27.

[0032] In the following description, one of the two motor generators 17 and 18 will be referred to as a first motor generator 17 and the other of the two motor generators 17 and 18 will be referred to as a second motor generator 18. The power transmission mechanism input shaft 99 is provided behind the input shaft 23 of the transmission case 13 and is coaxial with the input shaft 23. The power transmission mechanism input shaft 99 and the input shaft 23 are connected, and the power of the input shaft 23 is transmitted to the power transmission mechanism input shaft 99. The gear transmission mechanism 98 is provided between the power transmission mechanism input shaft 99 and the rotor support shaft 17b of the first motor generator 17, and is configured to transmit the power of the input shaft 23 to the first motor generator 17.

[0033] As shown in Fig. 3, the low-speed planetary transmission unit 100 includes a sun gear 101, planetary gears 102, an internal gear 103, and a carrier 104. The low-speed planetary transmission unit 100 is provided behind the second motor generator 18, with the rotational axis of the sun gear 101 and the rotor support shaft 18b of the second motor generator 18 positioned on the same axis. The internal gear 103 and the power transmission mechanism input shaft 99 are connected via a gear interlocking mechanism 105. The sun gear 101 is provided with a first input shaft 136, which is connected to the rotor support shaft 18b of the second motor generator 18.

[0034] In the low-speed planetary transmission unit 100, the power of the input shaft 23 is transmitted to the internal gear 103 to drive the internal gear 103, the driving force of the second motor generator 18 is transmitted to the sun gear 101 to drive the sun gear 101, the power from the engine 5 and the driving force of the second motor generator 18 are combined to produce a low-speed combined power, and the low-speed combined power is output from the carrier 104.

[0035] The low-speed clutch 100C is provided between the output section of the low-speed planetary transmission unit 100 and the input shaft 25a of the forward / reverse switching device 25, and is configured so that when switched to an engaged state (on state), it transmits the low-speed combined power output by the low-speed planetary transmission unit 100 to the forward / reverse switching device 25, and when switched to a disengaged state (off state), it cuts off the power transmission from the low-speed planetary transmission unit 100 to the forward / reverse switching device 25.

[0036] 3, the high-speed planetary transmission unit 110 includes a sun gear 111, planetary gears 112, an internal gear 113, and a carrier 114. The high-speed planetary transmission unit 110 is provided behind the first motor-generator 17, with the rotational axis of the sun gear 111 and the rotor support shaft 17b of the first motor-generator 17 positioned on the same axis. The carrier 114 is connected to the power train input shaft 99 via a gear interlocking mechanism 115. The sun gear 111 is provided with a second input shaft 137, and the second input shaft 137 is connected to the rotor support shaft 18b of the second motor-generator 18 via a gear interlocking mechanism 116 and the first input shaft 136.

[0037] In the high-speed planetary transmission unit 110, the power of the input shaft 23 is transmitted to the carrier 114 to drive the planetary gear 112, the driving force of the second motor-generator 18 is transmitted to the sun gear 111 to drive the sun gear 111, the engine power from the input shaft 23 and the driving force of the second motor-generator 18 are combined to produce a high-speed combined power, which is output from the internal gear 113. The high-speed combined power is a higher-speed combined power than the low-speed combined power produced by the low-speed planetary transmission unit 100.

[0038] The high-speed clutch 110C is provided between the output section of the high-speed planetary transmission section 110 and the input shaft 25a of the forward / reverse switching device 25, and is configured so that when switched to an engaged state (on state), it transmits the high-speed combined power output by the high-speed planetary transmission section 110 to the forward / reverse switching device 25, and when switched to a disengaged state (off state), it cuts off the power transmission from the high-speed planetary transmission section 110 to the forward / reverse switching device 25.

[0039] As shown in Fig. 3, the forward / reverse switching device 25 includes an input shaft 25a located rearward of the power train input shaft 99, and an output shaft 25b aligned parallel to the input shaft 25a. The input shaft 25a and the power train input shaft 99 are located on the same axis. A forward clutch 25c and a reverse clutch 25d are provided on the input shaft 25a. A forward gear mechanism 25e is provided between the forward clutch 25c and the output shaft 25b. A reverse gear mechanism 25f is provided between the reverse clutch 25d and the output shaft 25b.

[0040] In the forward / reverse switching device 25, the outputs of the low-speed clutch 100C and the high-speed clutch 110C are input to the input shaft 25a. When the forward clutch 25c is switched on, the power of the input shaft 25a is switched to forward power by the forward gear mechanism 25e and the forward clutch 25c, transmitted to the output shaft 25b, and output from the output shaft 25b. When the reverse clutch 25d is switched on, the power of the input shaft 25a is switched to reverse power by the reverse gear mechanism 25f and the reverse clutch 25d, transmitted to the output shaft 25b, and output from the output shaft 25b.

[0041] As shown in Fig. 3, the auxiliary transmission 26 includes an input shaft 26a connected to the output shaft 25b of the forward / reverse switching device 25, and an output shaft 26b provided rearward of the input shaft 26a. The input shaft 26a and the output shaft 26b are positioned on the same axis. A high-speed clutch 26c is provided between the rear portion of the input shaft 26a and the front portion of the output shaft 26b. A low-speed gear mechanism 26f and a low-speed clutch 26d are provided between the input shaft 26a and the rear portion of the output shaft 26b.

[0042] In the auxiliary transmission 26, the output of the forward / reverse switching device 25 is input to the input shaft 26a. When the high-speed clutch 26c is switched to the engaged position, the power of the input shaft 26a is transmitted to the output shaft 26b via the high-speed clutch 26c without being changed in speed, and high-speed power is output from the output shaft 26b. When the low-speed clutch 26d is switched to the engaged position, the power of the input shaft 26a is changed in speed to low-speed power by the low-speed gear mechanism 26f and the low-speed clutch 26d, transmitted to the output shaft 26b, and output from the output shaft 26b. The low-speed power is slower than the high-speed power that is output when the high-speed clutch 26c is switched to the engaged position.

[0043] 3, the rear wheel differential mechanism 19 includes an input shaft 19a to which the output of the auxiliary transmission 26 is input. The input shaft 19a is connected to the rear portion of the output shaft 26b of the auxiliary transmission 26. The gear interlocking mechanism 27 is provided across the output shaft 26b of the auxiliary transmission 26 and the input shaft 20a of the front wheel transmission 20, and is configured to transmit the power of the output shaft 26b of the auxiliary transmission 26 to the input shaft 20a of the front wheel transmission 20.

[0044] As shown in Fig. 3, the front wheel transmission 20 includes an input shaft 20a connected to the gear interlocking mechanism 27, and an output shaft 20e arranged parallel to the input shaft 20a. A constant speed clutch 20b and an increasing speed clutch 20c are provided on the input shaft 20a. A constant speed gear mechanism 20d is provided between the constant speed clutch 20b and the output shaft 20e. A increasing speed gear mechanism 20f is provided between the increasing speed clutch 20c and the output shaft 20e.

[0045] In the front wheel transmission 20, the output of the auxiliary transmission 26 is transmitted to the input shaft 20a by the gear interlocking mechanism 27. When the constant speed clutch 20b is switched to the engaged position, the power of the input shaft 20a is changed to constant speed power by the constant speed clutch 20b and the constant speed gear mechanism 20d, transmitted to the output shaft 20e, and output from the output shaft 20e. The constant speed power is power that drives the front wheels 1 at the same speed as the rear wheels 2. When the speed-up clutch 20c is switched to the engaged position, the power of the input shaft 20a is changed to increased speed power by the speed-up clutch 20c and the speed-up gear mechanism 20f, transmitted to the output shaft 20e, and output from the output shaft 20e. The increased speed power is power that drives the front wheels 1 at a higher speed than the rear wheels 2. The power of the output shaft 20e of the front wheel transmission 20 is transmitted to the front wheel differential mechanism 39 via the rotating shaft 38.

[0046] In the traveling power transmission device 15, when the front wheels 1 and the rear wheels 2 are driven, the power of the engine 5 and the driving force of the second motor generator 18 are transmitted to the front wheels 1 and the rear wheels 2.

[0047] That is, the power (engine power) from the engine 5 transmitted to the input shaft 23 and the driving force (motor power) of the second motor generator 18 are combined into a low-speed combined power by the low-speed planetary transmission unit 100. The power (engine power) from the engine 5 transmitted to the input shaft 23 and the driving force (motor power) of the second motor generator 18 are combined into a high-speed combined power by the high-speed planetary transmission unit 110. By switching the low-speed clutch 100C to an engaged state and the high-speed clutch 110C to a disengaged state, the low-speed combined power from the low-speed planetary transmission unit 100 is transmitted to the input shaft 25a of the forward / reverse switching device 25, and then from the output shaft 25b of the forward / reverse switching device 25 to the auxiliary transmission 26, and then from the auxiliary transmission 26 via the gear interlocking mechanism 27 to the rear wheel differential mechanism 19 and the front wheel transmission 20. By switching the high-speed clutch 110C to the engaged state and the low-speed clutch 100C to the disengaged state, the high-speed combined power from the high-speed planetary transmission section 110 is transmitted to the input shaft 25a of the forward / reverse travel switching device 25, then transmitted from the output shaft 25b of the forward / reverse travel switching device 25 to the auxiliary transmission 26, and then transmitted from the auxiliary transmission 26 to the rear wheel differential mechanism 19 and the front wheel transmission 20.

[0048] In the traveling power transmission device 15, when the front wheels 1 and rear wheels 2 are driven, power from the engine 5 transmitted to the input shaft 23 is input to the first motor generator 17 via the transmission mechanism input shaft 99 and the gear transmission mechanism 98, driving the first motor generator 17 to generate electricity, and the generated electricity can be supplied to the second motor generator 18 for driving. The supply of electricity to the second motor generator 18 is performed either via the battery 22, with the generated electricity being charged into the battery 22, or without the battery 22, with the generated electricity not being charged into the battery 22.

[0049] As shown in FIG. 3 , a clutch 45 is provided between the output shaft 5b and the input shaft 23. The clutch 45 is configured to be switched between an engaged state (ON state) and a disengaged state (OFF state) by a hydraulic solenoid valve or the like. When switched to the engaged state, the clutch 45 transmits power from the engine 5 to the electric transmission unit 16A and the geared transmission unit 16B, switching the hybrid transmission 16 to a hybrid mode in which the front wheels 1 and the rear wheels 2 are driven by the power of the engine 5 and the driving force of the second motor generator 18 and electricity is generated by the first motor generator 17. When switched to the disengaged state, the clutch 45 cuts off the power transmission from the engine 5 to the electric transmission unit 16A and the geared transmission unit 16B, switching the hybrid transmission 16 to an electric mode in which the front wheels 1 and the rear wheels 2 are driven only by the driving force of the second motor generator 18. A dry clutch may be used as the clutch 45.

[0050] As shown in FIG. 3, a trochoid pump 81 is provided on the input shaft 23 to supply lubricating oil to the first motor generator 17, the second motor generator 18, and the gear transmission mechanism 30.

[0051] [Work power transmission device] 1 and 2, the power take-off shaft 12 is supported at the rear of the transmission case 13. As shown in FIG. 2, a work power transmission device 40 that transmits the power of the engine 5 to the power take-off shaft 12 is housed in the transmission case 13.

[0052] 3, the work power transmission device 40 includes a power train input shaft 99 connected to the input shaft 23, a rotating shaft 41 that is provided rearward of the power train input shaft 99 and extends in the longitudinal direction of the vehicle body with its front portion connected to the rear portion of the power train input shaft 99, a work clutch 42 connected to the rear portion of the rotating shaft 41, and a power take-off shaft speed change device 43 that changes the speed of the output of the work clutch 42 and transmits it to the power take-off shaft 12. The axis of the rotating shaft 41 and the axis of the input shaft 23 are aligned on the same axis. The input shaft 23 and the rotating shaft 41 are interlocked and connected together directly or via a joint.

[0053] In the work power transmission device 40, the power of the input shaft 23 is transmitted to the rotating shaft 41, and then transmitted from the rotating shaft 41 to the power take-off shaft 12 via the work clutch 42 and the power take-off shaft speed change device 43. The work clutch 42 switches between an ON state in which power from the engine 5 is transmitted to the power take-off shaft 12, and a OFF state in which power transmission from the engine 5 to the power take-off shaft 12 is cut off.

[0054] [Motor generators, inverter devices] 4, the first motor generator 17 and the second motor generator 18 are arranged side by side in the width direction of the vehicle body inside the transmission case 13. The first motor generator 17 is arranged to the left of the second motor generator 18. However, the first motor generator 17 and the second motor generator 18 may also be arranged in the front-to-rear direction of the vehicle body.

[0055] As shown in Fig. 3, two inverter devices 21A, 21B are arranged. The first inverter device 21A is connected to the first motor generator 17, and the second inverter device 21B is connected to the second motor generator 18. The same battery 22 is connected to the first inverter device 21A and the second inverter device 21B. The first inverter device 21A converts AC power from the first motor generator 17 into DC power and supplies it to the battery 22. The second inverter device 21B converts DC power from the battery 22 into AC power and supplies it to the second motor generator 18. It is possible to provide batteries 22 that are connected separately to the first inverter device 21A and the second inverter device 21B.

[0056] 1, 2, 4, 5, and 6, the first inverter unit 21A is provided in a space between the front wheels 1 and the rear wheels 2 and below the floor 11 of the driver's section 9, at a location on the left side of the vehicle body with respect to the running power transmission device 15, and the second inverter unit 21B is provided in a space between the front wheels 1 and the rear wheels 2 and below the floor 11 of the driver's section 9, at a location on the right side of the vehicle body with respect to the running power transmission device 15. Maintenance of each of the first inverter unit 21A and the second inverter unit 21B is possible from the outer lateral side of the vehicle body via between the front wheels 1 and the rear wheels 2. In this embodiment, the first inverter device 21A is provided at a location located on the left side of the vehicle body relative to the running power transmission device 15, and the second inverter device 21B is provided at a location located on the right side of the vehicle body relative to the running power transmission device 15. However, instead of this, it is possible to provide the first inverter device 21A at a location located on the right side of the vehicle body relative to the running power transmission device 15, and the second inverter device 21B at a location located on the left side of the vehicle body relative to the running power transmission device 15. In this embodiment, a connection structure is adopted in which the inverter device 21A on the left side of the vehicle body of the two inverter devices 21A, 21B is connected to the motor generator 17 on the left side of the vehicle body of the two motor generators 17, 18, and the inverter device 21B on the right side of the vehicle body of the two inverter devices 21A, 21B is connected to the motor generator 18 on the right side of the vehicle body of the two motor generators 17, 18. However, it is also possible to adopt a connection structure in which the inverter device 21A on the left side of the vehicle body of the two inverter devices 21A, 21B is connected to the motor generator 18 on the right side of the vehicle body of the two motor generators 17, 18, and the inverter device 21B on the right side of the vehicle body of the two inverter devices 21A, 21B is connected to the motor generator 17 on the left side of the vehicle body of the two motor generators 17, 18.

[0057] 1 and 2, the first inverter device 21A, the second inverter device 21B, the first motor generator 17, and the second motor generator 18 are provided at the same position in the longitudinal direction of the vehicle body. The first inverter device 21A is located near the first motor generator 17, and the second inverter device 21B is located near the second motor generator 18.

[0058] 4, the first inverter device 21A is supported by a first support member 54 provided between the first inverter device 21A and the transmission case 13, and is supported on the transmission case 13 via the first support member 54. The second inverter device 21B is supported by a second support member 55 provided between the second inverter device 21B and the transmission case 13, and is supported on the transmission case 13 via the second support member 55.

[0059] [Another Example] (1) In the above embodiment, an example in which two motor generators (electric motors) 17, 18 are provided is shown, but only one motor generator or three or more motor generators (electric motors) may be provided.

[0060] (2) In the above embodiment, the traveling power transmission device 15 includes the transmission case 13 and the hybrid transmission 16 provided inside the transmission case 13, but the present invention is not limited to this, and the traveling power transmission device may include only a rotating shaft that transmits power to the rear wheels 2. In addition, in the present embodiment, the present invention is not limited to this, and the traveling power transmission device may include a transmission that does not include an engine and transmits only the driving force of an electric motor to the rear wheels 2.

[0061] (3) In the above embodiment, an example is shown in which power is transmitted to the front wheels 1 and the rear wheels 2, but power may not be transmitted to the front wheels 1 and may be transmitted only to the rear wheels 2.

[0062] (4) In the above embodiment, the rear wheels 2 are provided as the rear traveling device, but a mini crawler traveling device may be provided as the rear traveling device.

[0063] (5) In the above embodiment, the two motor generators 17, 18 have the same outer diameter. However, the two motor generators 17, 18 may have different outer diameters.

[0064] (6) In the above embodiment, an example is shown in which both the first and second inverter devices 21A, 21B and both the first and second motor generators 17, 18 are located at the same position in the fore-and-aft direction of the vehicle body, but they may also be located at different positions in the fore-and-aft direction of the vehicle body. [Industrial Applicability]

[0065] The present invention can be applied to a work vehicle equipped with an electric motor connected to a transmission that outputs power toward the rear wheels (rear traveling device). [Explanation of symbols]

[0066] 1 front wheel 2 Rear wheels (rear running gear) 9 Driving Department 11 Floor 13 Mission case 15. Driving power transmission device 16 Transmission (Hybrid Transmission) 17 Electric motor (first motor generator) 18 Electric motor (second motor generator) 21A inverter device 21B Inverter device 50 Steps for boarding and alighting 54 First support member 55 Second support member

Claims

1. A running body supported by front wheels and a rear running device is provided, The traveling vehicle body is provided with a driving section having a floor section for riding, a traveling power transmission device that transmits power to the rear traveling device, and an electric motor connected to the traveling power transmission device, two inverter devices connected to the electric motor; One of the two inverter devices is provided in a space between the front wheels and the rear traveling device and below the floor, at a location located on one side of the traveling power transmission device in the vehicle body width direction, the other of the two inverter devices is provided in a space between the front wheels and the rear traveling device and below the floor, at a location on the other side of the traveling power transmission device in the vehicle body width direction, In a plan view, the two inverter devices overlap with the floor portion, A step for getting on and off is provided on the outer side of the driver's section, The two inverter devices are provided at a center portion of the vehicle body in a width direction relative to the boarding / exiting step.

2. 2. The work vehicle according to claim 1, wherein the traveling power transmission device comprises a transmission case and a transmission provided inside the transmission case.

3. Two electric motors are provided, one of the two electric motors is connected to one of the two inverter devices; 3. The work vehicle according to claim 1, wherein the other of the two electric motors is connected to the other of the two inverter devices.

4. Two electric motors are provided, 3. The work vehicle according to claim 2, wherein the two electric motors and the two inverter devices are disposed in the same position in the longitudinal direction of the vehicle body, and the two electric motors are provided inside the transmission case.

5. 5. The work vehicle according to claim 4, wherein the two electric motors are arranged in a direction parallel to the width of the vehicle body.

6. a first support member is provided between a first inverter device of the two inverter devices and the transmission case, and supports the first inverter device; 6. The work vehicle according to claim 4, further comprising a second support member disposed between a second inverter device of the two inverter devices and the transmission case, for supporting the second inverter device.

Citation Information

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