Electric work vehicle

Abstract

To arrange components for electrification efficiently in an electric work vehicle to achieve downsizing of the electric work vehicle.SOLUTION: An electric work vehicle includes a vehicle body, a travel device, an engine, a cooling unit, a power generator, an electric motor, and an electric power control device. The travel device is attached to the vehicle body. The engine is disposed in the vehicle body. The cooling unit is disposed in the vehicle body and placed rearward of the engine. The power generator is driven by the engine. The electric motor is driven by electric power from the power generator and operates the travel device. The electric power control device includes a converter and / or an inverter. The electric power control device is disposed between the engine and the cooling unit in a vehicle front-back direction and supplies electric power from the power generator to the electric motor.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to an electric work vehicle. [Background technology]

[0002] A work vehicle such as a bulldozer is equipped with an engine and a cooling unit. For example, in the work machine disclosed in Patent Document 1, the engine is disposed in front of the cab and the cooling unit is disposed behind the cab. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4496048 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, work vehicles have become increasingly electric. For example, an electric work vehicle includes an engine, a generator, a power control device, and an electric motor. The generator generates electricity when driven by the engine. The power control device includes, for example, a converter or inverter, and supplies power from the generator to the electric motor. The electric motor is driven by power from the generator to operate the crawler.

[0005] The electric work vehicle described above must be equipped with components for electrification, such as a generator, a power control device, and an electric motor, in addition to an engine and a radiator. However, doing so raises concerns that the vehicle will become larger. An object of the present disclosure is to reduce the size of the electric work vehicle by efficiently arranging the components for electrification in the electric work vehicle. [Means for solving the problem]

[0006] An electric work vehicle according to one aspect of the present disclosure includes a vehicle body, a traveling device, an engine, a cooling unit, a generator, an electric motor, and a power control device. The traveling device is attached to the vehicle body. The engine is disposed on the vehicle body. The cooling unit is disposed on the vehicle body and rearward of the engine. The generator is driven by the engine. The electric motor is driven by power from the generator and operates the traveling device. The power control device includes a converter and / or an inverter. The power control device is disposed between the engine and the cooling unit in the fore-and-aft direction of the vehicle, and supplies power from the generator to the electric motor. [Effects of the Invention]

[0007] According to the present disclosure, components are efficiently arranged in an electric work vehicle, thereby reducing the size of the electric work vehicle. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view of an electric work vehicle according to an embodiment. [Figure 2] FIG. 2 is a schematic diagram showing a drive system of the electric work vehicle. [Figure 3] FIG. 1 is a side view of an electric working machine. [Figure 4] FIG. 1 is a top view of an electric work machine. [Figure 5] FIG. [Figure 6] FIG. 10 is a side view of an electric working machine according to a modified example. [Figure 7] FIG. 10 is a top view of an electric working machine according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] Embodiments of the present disclosure will now be described with reference to the drawings. Fig. 1 is a perspective view showing an electric work vehicle 1 according to an embodiment. The electric work vehicle 1 according to this embodiment is a bulldozer. As shown in Fig. 1, the electric work vehicle 1 includes a vehicle body 2, a work implement 3, and a pair of traveling devices 4A, 4B.

[0010] The vehicle body 2 includes a cab 11 and an engine compartment 12. A driver's seat and operating members such as levers and pedals (not shown) are arranged inside the cab 11. The engine compartment 12 is arranged in front of the cab 11. The upper surface of the engine compartment 12 is inclined forward and downward. The vehicle body 2 also includes a hydraulic oil tank 13 and a fuel tank 14 (see FIG. 5). The hydraulic oil tank 13 and the fuel tank 14 are arranged on the left and right sides of the cab 11, respectively.

[0011] The pair of traveling units 4A, 4B are each attached to the vehicle body 2. The pair of traveling units 4A, 4B are disposed on the left and right sides of the vehicle body 2, respectively. The left traveling unit 4A includes a track frame 15A, a sprocket 16A, and a track 17A. The track frame 15A supports the track 17A. The sprocket 16A is rotatably supported relative to the track frame 15A. When the sprocket 16A is driven, the track 17A operates, thereby causing the electric work vehicle 1 to travel. The right traveling unit 4B is provided symmetrically to the left traveling unit 4A. The configuration of the right traveling unit 4B is the same as that of the left traveling unit 4A, so a detailed description will be omitted.

[0012] The work implement 3 is attached to the vehicle body 2 so as to be operable relative to the vehicle body 2. The work implement 3 includes a blade 18 and work implement actuators 19A, 19B (see FIG. 4). The blade 18 is disposed in front of the vehicle body 2. The work implement actuators 19A, 19B are connected to the blade 18 and the vehicle body 2. The work implement actuators 19A, 19B are hydraulic cylinders. The work implement actuators 19A, 19B operate the blade 18 by extending and retracting using hydraulic pressure.

[0013] FIG. 2 is a schematic diagram showing the drive system of the electric work vehicle 1. As shown in FIG. 2, the electric work vehicle 1 is equipped with an engine 21, a PTO (Power Take Off) 22, a hydraulic pump 23, and a generator 24. The engine 21 is an internal combustion engine such as a diesel engine. The PTO 22 is connected to the engine 21. The PTO 22 distributes driving power from the engine 21 to the generator 24 and the hydraulic pump 23. Note that the PTO 22 may be omitted. In that case, the generator 24 and the hydraulic pump 23 may be connected to each other in series with respect to the engine 21.

[0014] The hydraulic pump 23 is driven by the driving force from the engine 21 to discharge hydraulic oil. The hydraulic pump 23 is connected to the work implement actuators 19A, 19B via a control valve 25. The work implement actuators 19A, 19B are driven by the hydraulic oil from the hydraulic pump 23. As a result, the work implement 3 operates.

[0015] The generator 24 generates electricity by being driven by the driving force from the engine 21. The electric work vehicle 1 is equipped with a power control device 26, a first traveling motor 28A, and a second traveling motor 28B. The first traveling motor 28A and the second traveling motor 28B are electric motors. The power control device 26 supplies electric power from the generator 24 to the first traveling motor 28A and the second traveling motor 28B via the PDU 27.

[0016] The first traveling motor 28A is connected to the sprocket 16A of the left traveling unit 4A. The second traveling motor 28B is connected to the sprocket 16B of the right traveling unit 4B. The first traveling motor 28A is driven by power from the generator 24, thereby operating the left crawler 17A. The second traveling motor 28B is driven by power from the generator 24, thereby operating the right crawler 17B. Note that reducers may be incorporated inside the first traveling motor 28A and the second traveling motor 28B. The first traveling motor 28A and the second traveling motor 28B may be provided in the reversed left-right orientation.

[0017] The power control device 26 includes a converter 31, a first inverter 32A, a second inverter 32B, and a distribution board 27 (hereinafter referred to as PDU). The converter 31 is connected to the generator 24. The converter 31 converts AC current from the generator 24 into DC current. The first inverter 32A and the second inverter 32B are connected to the converter 31 via the PDU 27. The first inverter 32A is connected to the first traveling motor 28A. The first inverter 32A converts the DC current from the converter 31 into AC current of a predetermined voltage or a predetermined frequency and supplies it to the first traveling motor 28A. The second inverter 32B is connected to the second traveling motor 28B. The second inverter 32B converts the DC current from the converter 31 into AC current of a predetermined voltage or a predetermined frequency and supplies it to the second traveling motor 28B.

[0018] The electric work vehicle 1 is equipped with a brake resistor 33. The brake resistor 33 is connected to the power control device 26. When the electric work vehicle 1 decelerates, the brake resistor 33 generates a deceleration force in the first traveling motor 28A and the second traveling motor 28B.

[0019] The electric work vehicle 1 is equipped with a cooling unit 34 and an oil cooler 35. The oil cooler 35 is water-cooled. The cooling unit 34 includes a first cooling device 36, a second cooling device 37, a cooling fan 38, and a fan motor 39. The first cooling device 36 is a water-cooled cooling device for the power control device 26. The first cooling device 36 is, for example, a radiator. The first cooling device 36 is connected to the converter 31, the first inverter 32A, the second inverter 32B, and the oil cooler 35 via a water-cooled circuit 41. A water-cooled pump 42 is connected to the water-cooled circuit 41. The first cooling device 36 cools the cooling water flowing through the converter 31, the first inverter 32A, the second inverter 32B, and the oil cooler 35.

[0020] The second cooling device 37 is a water-cooled cooling device for the engine 21. The second cooling device 37 is, for example, a radiator. The second cooling device 37 is connected to the engine 21 via a water-cooling circuit (not shown). The second cooling device 37 cools the coolant for the engine 21. The cooling fan 38 is connected to a fan motor 39. The fan motor 39 is a hydraulic motor. The fan motor 39 is driven by hydraulic oil from the hydraulic pump 23 to rotate the cooling fan 38. As a result, the cooling fan 38 generates cooling air that passes through the first cooling device 36 and the second cooling device 37.

[0021] The oil cooler 35 is connected to the generator 24, the first travel motor 28A, and the second travel motor 28B via an oil cooling circuit 43. An oil cooling pump 44 is connected to the oil cooling circuit 43. The oil cooler 35 cools the lubricating oil flowing through the generator 24, the first travel motor 28A, and the second travel motor 28B by exchanging heat with the cooling water flowing through the water cooling circuit 41 described above.

[0022] Next, the arrangement of the components of the electric work vehicle 1 will be described. Fig. 3 is a side view of the electric work vehicle 1. Fig. 4 is a top view of the electric work vehicle 1. Fig. 5 is a rear view of the electric work vehicle 1. As shown in Figs. 3 to 5, the engine 21 is disposed in the vehicle body 2. The engine 21 is disposed in the engine compartment 12. The PTO 22, generator 24, and hydraulic pump 23 are disposed behind the engine 21 on the vehicle body 2. The PTO 22, generator 24, and hydraulic pump 23 are disposed below the cab 11.

[0023] The cooling unit 34 is disposed rearward of the engine 21 in the vehicle body 2. The cooling unit 34 is disposed rearward of the cab 11. The PTO 22, the generator 24, and the hydraulic pump 23 are disposed between the engine 21 and the cooling unit 34 in the front-to-rear direction of the vehicle.

[0024] The first travel motor 28A is disposed within the width of the crawler track 17A. Alternatively, at least a portion of the first travel motor 28A may be disposed within the crawler track 17A. At least a portion of the first travel motor 28A is disposed below the cooling unit 34. In a side view of the vehicle, the center axis C1 of the first travel motor 28A is located forward of the rear end 341 of the cooling unit 34. The second travel motor 28B is disposed within the width of the crawler track 17B. Alternatively, at least a portion of the second travel motor 28B may be disposed within the crawler track 17B. The second travel motor 28B is disposed symmetrically with the first travel motor 28A. However, the first travel motor 28A and the second travel motor 28B may be disposed left-right reversely to the above.

[0025] The oil cooler 35 is disposed rearward of the engine 21 in the vehicle body 2. The oil cooler 35 is disposed between the engine 21 and the cooling unit 34 in the vehicle longitudinal direction. The oil cooler 35 is disposed below the cab 11. The brake register 33 is disposed rearward of the engine 21 in the vehicle body 2. The brake register 33 is disposed between the engine 21 and the cooling unit 34 in the vehicle longitudinal direction. The brake register 33 is disposed below the cab 11.

[0026] The power control device 26 is disposed in front of the cooling unit 34 on the vehicle body 2. The power control device 26 is disposed between the engine 21 and the cooling unit 34 in the vehicle longitudinal direction. The power control device 26 is disposed between the generator 24 and the cooling unit 34 in the vehicle longitudinal direction. The power control device 26 may also be disposed between the engine 21 and the traction motors 28A, 28B in the vehicle longitudinal direction.

[0027] The power control device 26 is disposed below the cab 11. The power control device 26 is disposed above the first traveling motor 28A. The power control device 26 is disposed above the oil cooler 35. The power control device 26 is disposed above the brake resistor 33.

[0028] As shown in Fig. 5, the first inverter 32A and the second inverter 32B are arranged side by side in the left-right direction of the vehicle. The converter 31 is arranged above the first inverter 32A and the second inverter 32B. The PDU 27 is arranged above the converter 31. The PDU 27 is arranged between the engine 21 and the cooling unit 34 in the front-rear direction of the vehicle. For ease of understanding, the converter 31, PDU 27, brake register 33, and oil cooler 35 are omitted from Fig. 4.

[0029] As described above, in the electric work vehicle 1 according to this embodiment, the components are arranged efficiently, which allows the electric work vehicle 1 to be made smaller.

[0030] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the gist of the invention.

[0031] The electric work vehicle 1 is not limited to a bulldozer, but may be another vehicle such as a wheel loader. The arrangement of the components of the electric work vehicle 1 is not limited to that in the above embodiment and may be changed. For example, a portion of the first travel motor 28A and the second travel motor 28B may be arranged inside the tracks 17A, 17B, and the other portions of the first travel motor 28A and the second travel motor 28B may be arranged outside the tracks 17A, 17B.

[0032] Fig. 6 is a side view of an electric work vehicle 1 according to a modified example. Fig. 7 is a top view of an electric work vehicle 1 according to a modified example. As shown in Figs. 6 and 7, the first traveling motor 28A and the second traveling motor 28B may be disposed inside the vehicle body 2, rather than inside the tracks 17A, 17B.

[0033] The configuration of the water cooling circuit 41 of the electric work vehicle 1 is not limited to that of the above embodiment and may be modified. The configuration of the oil cooling circuit 43 of the electric work vehicle 1 is not limited to that of the above embodiment and may be modified. [Industrial Applicability]

[0034] According to the present disclosure, components are efficiently arranged in an electric work vehicle, thereby reducing the size of the electric work vehicle. [Explanation of symbols]

[0035] 2: Body, 11: Cab, 12: Engine compartment, 17A, 17B: Tracks, 18: Blade, 21: Engine, 24: Generator, 26: Power control device, 27: Distribution board, 28A: First travel motor, 28B: Second travel motor, 31: Converter, 32A: First inverter, 32B: Second inverter, 33: Brake resistor, 34: Cooling unit, 35: Oil cooler

Claims

1. The car body and a running device attached to the vehicle body; an engine disposed in the vehicle body; a radiator disposed on the vehicle body and positioned rearward of the engine; a generator disposed on the vehicle body and driven by the engine; an electric motor driven by electric power from the generator to operate the traveling device; a power control device including a converter and / or an inverter, disposed between the engine and the radiator in the vehicle longitudinal direction, and configured to supply electric power from the generator to the electric motor; An electric work vehicle equipped with:

2. a cab disposed on the vehicle body; an engine compartment disposed in front of the cab; a blade disposed in front of the engine compartment; Furthermore, the engine is disposed in the engine compartment, The radiator is disposed behind the cab. The electric work vehicle according to claim 1 .

3. The power control device is disposed below the cab. The electric work vehicle according to claim 2 .

4. the traveling device includes a crawler track disposed on a side of the vehicle body, At least a portion of the electric motor is disposed within the track. The electric work vehicle according to claim 1 .

5. The power control device is disposed above the electric motor. The electric work vehicle according to claim 1 .

6. In a side view of the vehicle, a central axis of the electric motor is located forward of a rear end of the radiator. The electric work vehicle according to claim 1 .

7. The electric motor is disposed within the vehicle body. The electric work vehicle according to claim 1 .

8. the power control device is disposed between the engine and the electric motor in the vehicle front-rear direction; The electric work vehicle according to claim 1 .

9. The power control device further includes a distribution board. The electric work vehicle according to claim 1 .

10. The distribution board is disposed above the converter and / or the inverter. The electric work vehicle according to claim 9.

11. The electric motor further includes an oil cooler that cools the lubricating oil of the electric motor. The oil cooler is disposed between the engine and the radiator in the vehicle front-rear direction. The electric work vehicle according to claim 1 .

12. The power control device is disposed above the oil cooler. The electric work vehicle according to claim 11.

13. a brake resistor connected to the power controller; The brake resistor is disposed between the engine and the radiator in the vehicle longitudinal direction. The electric work vehicle according to claim 1 .

14. The power control device is disposed above the brake resistor. The electric work vehicle according to claim 13.

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