Work vehicle

Abstract

This work vehicle is provided with: an engine 21; a muffler 22 which is disposed adjacent to the engine 21 and discharges exhaust of the engine 21 to the outside; a cooling unit 23 which cools hydraulic oil stored in a hydraulic oil tank 43 while circulating the hydraulic oil by a hydraulic pump 10; and a separation plate 53 which separates the muffler 22 and the cooling unit 23.

Description

Work vehicle

[0001] The present invention relates to a work vehicle equipped with an engine.

[0002] As an example of a work vehicle, there is a work vehicle in which a hydraulic pump is driven by the power of an engine and hydraulic equipment is operated by hydraulic oil from the hydraulic pump (see, for example, Patent Document 1). In this work vehicle, a cooling unit (radiator) for cooling the hydraulic oil supplied to the hydraulic pump or the like is provided behind the engine, and is configured to be cooled by cooling air, and the cooling air is discharged backward.

[0003] Japanese Patent Application Laid-Open No. 2024-4327

[0004] A muffler for discharging the exhaust of the engine to the outside is provided around the engine in a state of being arranged side by side with the engine. In the above conventional configuration, the air around the engine is ventilated toward the rear of the vehicle body. However, since high-temperature exhaust is discharged from the muffler, high-temperature air is supplied to the cooling unit, resulting in a disadvantage that the cooling efficiency in the cooling unit is lowered.

[0005] An object of the present invention is to prevent a decrease in the cooling efficiency of the cooling unit.

[0006] A characteristic configuration of the work vehicle according to the present invention is that it includes an engine, a muffler that is arranged side by side with the engine and discharges the exhaust of the engine to the outside, a cooling unit, and a partition plate that partitions the muffler and the cooling unit.

[0007] According to the present invention, since a partition plate is provided between the muffler and the cooling unit, it is possible to avoid the high-temperature air discharged from the muffler from flowing directly toward the cooling unit. Therefore, it is possible to prevent a decrease in the cooling efficiency in the cooling unit.

[0008] In the present invention, it is preferable that a cooling fan for generating cooling air for the cooling unit is arranged between the cooling unit and the partition plate.

[0009] In this configuration, since there is a cooling fan between the cooling unit and the partition plate, the high-temperature air generated from the muffler does not affect the cooling airflow. Therefore, the cooling fan generates cooling airflow without being affected by the heat from the muffler, and the cooling unit can be efficiently cooled by that cooling airflow.

[0010] In the present invention, it is preferable that the rotating shaft of the cooling fan extends in the direction in which the engine and the cooling unit are aligned.

[0011] According to this configuration, by arranging the engine's output shaft in the direction of alignment between the engine and the cooling unit, the rotation shaft of the cooling fan and the engine's output shaft can be directly connected, and the drive structure can be simplified without the need for complexity such as the use of a belt drive mechanism.

[0012] In the present invention, it is preferable that the cooling fan is provided so that cooling air flows from the cooling unit side to the engine side, and that the partition plate is configured to receive and disperse the cooling air from the cooling fan.

[0013] In this configuration, cooling air is drawn in from the outside of the cooling unit side in the direction of alignment between the engine and the cooling unit, passes through the cooling unit, and is blown toward the partition plate. The cooling air is received and dispersed by the partition plate and released outwards. As a result, the cooling unit can be efficiently cooled by the cool air on the outside of the cooling unit side.

[0014] In the present invention, it is preferable that the muffler has an exhaust port formed therein that discharges exhaust in a direction intersecting the direction in which the engine and the cooling unit are aligned.

[0015] In this configuration, exhaust from the engine is not discharged along the direction in which the engine and cooling unit are aligned, but rather along a direction intersecting that direction. Therefore, the engine and cooling unit are separated by a partition plate, and since the exhaust is discharged in a direction intersecting the direction of alignment, the impact of the exhaust on the cooling unit can be minimized.

[0016] In the present invention, the engine, the partition plate, and the cooling unit are arranged in a manner aligned along the longitudinal direction of the aircraft, and it is preferable that a control unit is provided at one end of the longitudinal side of the aircraft where the cooling unit is located.

[0017] In this configuration, the control panel is located on the outer side of the cooling unit in the direction of alignment between the engine and the cooling unit. Therefore, cooling air is drawn into the area where the control panel is located, preventing the deterioration of the operating environment by avoiding disadvantages such as heated air after cooling being blown onto the driver operating the controls.

[0018] In the present invention, the system comprises a hydraulic pump driven by the engine, a plurality of work devices operated by hydraulic fluid supplied from the hydraulic pump, and a hydraulic fluid tank for storing the hydraulic fluid, and the cooling unit is preferably an oil cooler that cools the hydraulic fluid while circulating the hydraulic fluid stored in the hydraulic fluid tank.

[0019] In this configuration, hydraulic fluid is supplied from the hydraulic fluid tank to the hydraulic equipment by a hydraulic pump. When this supply operation is repeated, the temperature of the hydraulic fluid rises, but the hydraulic fluid stored in the hydraulic fluid tank is circulated to an oil cooler, and the cooling air from a cooling fan is directed onto the oil cooler to cool it. At this time, the oil cooler can efficiently cool the hydraulic fluid without being affected by the high temperature from the muffler.

[0020] This is a side view of the work vehicle. This is a top view of the work vehicle. This is a front view of the work vehicle. This is a side view of the articulating link mechanism. This is a side view showing the main part of the vehicle body. This is a top view showing the main part of the vehicle body. This is a front view showing the main part of the vehicle body. This is a rear view cross-sectional view showing the configuration of the partition plate and the arrangement of the upper part of the vehicle body.

[0021] An embodiment of the work vehicle of the present invention will be described based on the drawings. In the following description, the direction of arrow FW shown in the drawings will be "forward", the direction of arrow BK will be "rear", the direction of arrow RH will be "right", the direction of arrow LH will be "left", the direction of arrow UP will be "up", and the direction of arrow DW will be "down".

[0022] As shown in Figures 1 to 3, the work vehicle of this embodiment is equipped with a vehicle body 1 that is roughly rectangular in plan view and supports the entire vehicle, a plurality of running wheels 2, and an articulated link mechanism 3 that supports the plurality of running wheels 2 on the vehicle body 1 so that each can be raised and lowered individually. A loading platform 4 capable of loading cargo such as containers is provided on the upper part of the vehicle body 1. A steering control unit 5 extends rearward from the rear of the vehicle body 1. The steering control unit 5 is equipped with a steering lever 6 for controlling the movement of the vehicle body. The steering lever 6 is configured as a joystick that can be swung forward, backward, left and right, and allows for easy switching between forward, reverse, and turning movements.

[0023] The running wheels 2 are located at the front and rear on both the left and right sides of the vehicle body 1. In this embodiment, the work vehicle is equipped with four running wheels 2: left front, right front, left rear, and right rear. Each of the four running wheels 2 is individually rotationally driven by a hydraulic motor M, which serves as a working device. Multiple hydraulic cylinders 8 and 9 are provided as working devices that can individually change the posture of the articulated link mechanism 7, and the four running wheels 2 are supported via the articulated link mechanism 7 so that they can be individually raised and lowered relative to the vehicle body 1.

[0024] As shown in Figure 4, the articulated link mechanism 7 includes a base end 14 supported by the vehicle body 1, a first link 15 whose upper end is supported at the lower part of the base end 14 so as to be rotatable around a horizontal axis X1, and a second link 16 whose one end is supported at the lower end of the first link 15 so as to be rotatable around a horizontal axis X2 and whose other end is supported by a running wheel 2.

[0025] A support bracket 17 supporting the running wheel 2 is supported by a boss portion 18 provided at the other end of the second link 16 so as to be able to swing around the vertical axis Y. A hydraulic cylinder 20 for swivel operation as a working device is provided extending from the bracket 19 at one end of the second link 16 to the arm portion 17a provided on the support bracket 17.

[0026] Each of the multiple articulated link mechanisms 7 is provided with multiple hydraulic cylinders 8 and 9 capable of individually changing the orientation of each articulated link mechanism 7. Specifically, there is a first hydraulic cylinder 8 capable of changing the swinging orientation of the first link 15 relative to the vehicle body 1, and a second hydraulic cylinder 9 capable of changing the swinging orientation of the second link 16 relative to the first link 15.

[0027] Auxiliary wheels 2A are rotatably supported at the intermediate bending portion of each of the multiple bending link mechanisms 7. The auxiliary wheels 2A are made of wheels with a smaller diameter than the running wheels 2. The pivot shaft that pivotally connects the first link 15 and the second link 16 is extended so as to protrude outward in the width direction of the vehicle body, and the auxiliary wheels 2A are rotatably supported at the extended protruding portion of the pivot shaft.

[0028] By operating the hydraulic cylinder 20 for swivel, the travel wheels 2 can be rotated around the vertical axis Y relative to the articulated link mechanism 7, thereby enabling a swivel operation.

[0029] The position of each running wheel 2 relative to the vehicle body 1 can be changed by supplying and discharging hydraulic fluid to multiple first hydraulic cylinders 8, multiple second hydraulic cylinders 9, and a slewing hydraulic cylinder 20. Furthermore, the rotational speed of the hydraulic motor M, i.e., the rotational speed of the running wheels 2, can be changed by adjusting the flow rate of the hydraulic fluid corresponding to the hydraulic motor M. A separate hydraulic motor is provided for each of the four running wheels 2, and the rotational speed of the running wheels 2 can be changed independently.

[0030] The upper part of the vehicle body 1 is equipped with a hydraulic control mechanism 12 that individually supplies and discharges hydraulic fluid from the hydraulic pump 10 to each hydraulic device (hydraulic cylinders 8, 9, hydraulic motor M, etc.) and adjusts the flow rate, and an ECU (Electronic Control Unit) 13 that controls the operation of the hydraulic control mechanism 12. The hydraulic control mechanism 12 is equipped with multiple control valves (not shown) for individually supplying and discharging hydraulic fluid and adjusting the flow rate to multiple hydraulic cylinders 8, 9, 20 and multiple hydraulic motors M. Multiple hydraulic cylinders 8, 9, 20 and multiple hydraulic motors M correspond to multiple work devices that are operated by hydraulic fluid supplied from the hydraulic pump 10. The upper side of the vehicle body 1 is covered by a cover body 11.

[0031] The lower part of the vehicle body 1 is equipped with a hydraulic pump 10 that supplies hydraulic fluid to a plurality of hydraulic cylinders 8, 9, 20 and a plurality of hydraulic motors M, an engine 21 that drives the hydraulic pump 10, a muffler 22 that is placed next to the engine 21 and discharges the exhaust of the engine 21 to the outside, an oil cooler 23 that serves as a cooling unit for cooling the hydraulic fluid, and a cooling fan 24 that blows cooling air to the oil cooler 23.

[0032] The vehicle body 1 is entirely supported by a vehicle frame 25. As shown in Figures 5 and 6, the vehicle frame 25 comprises an upper frame portion 26 formed in a rectangular frame shape in plan view, and a lower frame portion 27 formed in a rectangular frame shape in plan view, with the upper frame portion 26 and the lower frame portion 27 being integrally connected by a plurality of upper and lower connecting members 28. The lower frame portion 27 is provided with a plurality of horizontal bars 29 extending in the left-right direction.

[0033] The base ends 14 of each of the four articulated link mechanisms 7 are connected to the side of the vehicle frame 25, and the vehicle body can be supported by the four running wheels via the articulated link mechanisms. The hydraulic control mechanism and the ECU 13 are supported on the vehicle frame 25.

[0034] As shown in Figures 5 and 7, vertical frame members 30 are provided below the vehicle body frame 25. The vertical frame members 30 are provided at two locations in the front-rear direction of the vehicle body frame 25. The vertical frame members 30 are provided so as to extend downward from the vehicle body frame 25 along the vertical direction of the vehicle body.

[0035] The vertical frame members 30 are formed by bending a round pipe into a roughly U-shape when viewed in the front-rear direction, and their upper ends are connected to the vehicle body frame 25. As shown in Figure 5, the front and rear vertical frame members 30 are connected by a plurality of front-rear oriented frame members 31 that extend in the front-rear direction. The front-rear oriented frame members 31 are provided on both the left and right sides, at the lower and upper parts of the vertical frame members 30, respectively. The lower front-rear oriented frame member 31a is made of a straight round pipe, and the upper front-rear oriented frame member 31b is made of an angle material.

[0036] A pair of front-to-rear support members 32 are provided, extending across the lower parts of the front and rear vertical frame members 30. At the front of the vehicle body 1, the engine 21 is mounted and supported by a pair of front-to-rear support members 33, which are supported across the left and right front-to-rear support members 32.

[0037] A hydraulic pump 10 is located on the right side of the engine 21 and is supported by a support member 34 that spans across the left and right front-to-rear support members 32. The output shaft 35 of the engine 21 is positioned to protrude rearward along the front-to-rear direction of the vehicle body. A belt transmission mechanism 39 is provided between the output shaft 35 of the engine 21 and the rotation shaft of the hydraulic pump 10, and is configured to operate the hydraulic pump 10 using the power of the engine 21.

[0038] A muffler 22 is provided alongside the rear of the engine 21. The muffler 22 is cylindrical in shape. The muffler 22 is provided with an exhaust port 40 that discharges exhaust gases in the direction lateral to the vehicle body, which is an example of a direction intersecting the direction in which the engine 21 and the oil cooler 23 are aligned. Above the engine 21 is a fuel tank 41 that stores the fuel supplied to the engine 21. The fuel tank 41 is supported by a bracket 42 that extends from the vehicle body frame 25.

[0039] A hydraulic oil tank 43 for storing hydraulic fluid is provided at the rear of the engine 21 and at the rear of the vehicle body 1. The hydraulic oil tank 43 is supported by left and right front-to-rear support members 32. The hydraulic oil tank 43 is fixed to the left and right front-to-rear support members 32 by a tightening band 44 that is wrapped around it from above. A battery 45 is provided at the rear end of the vehicle body 1 behind the hydraulic oil tank 43.

[0040] The hydraulic pump 10 draws hydraulic fluid stored in the hydraulic fluid tank 43 through the suction pipe 46 and supplies it through the supply pipe 47. The hydraulic fluid supplied through the supply pipe 47 is distributed and supplied to a plurality of control valves in the hydraulic control mechanism 12 through the distributor 48 and branch piping (not shown).

[0041] Any excess hydraulic fluid that is not supplied to the hydraulic control mechanism 12 is returned to the hydraulic fluid tank 43 through the return pipe 49. When the hydraulic fluid is not being used in the hydraulic control mechanism 12, the entire amount of hydraulic fluid from the supply pipe 47 is returned to the hydraulic fluid tank 43.

[0042] As shown in FIGS. 5 and 6, an oil cooler 23 is provided at the front-rear intermediate portion between the muffler 22 and the hydraulic oil tank 43. The oil cooler 23 is used to cool the hydraulic oil stored in the hydraulic oil tank 43. That is, the hydraulic oil is piped and connected to return to the hydraulic oil tank 43 after passing through the oil cooler 23 on the way back to the hydraulic oil tank 43 through the return pipe 49. The hydraulic oil stored in the hydraulic oil tank 43 is cooled when passing through the oil cooler 23 while circulating through the oil cooler 23 by the hydraulic pump 10. Thus, the oil cooler 23 functions as a cooling unit that cools the hydraulic oil while circulating the hydraulic oil stored in the hydraulic oil tank 43.

[0043] The lower end of the oil cooler 23 is supported by a support rod 50 that is erected and supported across the front-rear support bodies 32 on the lower sides of both the left and right sides. The upper end of the oil cooler 23 is supported by a support rod 51 that is erected and supported across the front-rear frame members 31b on the upper sides of both the left and right sides.

[0044] A cooling fan 24 that generates cooling air for the oil cooler 23 is provided at the front-rear intermediate portion between the muffler 22 and the oil cooler 23. The cooling fan 24 is rotationally driven by the power of the engine 21. The output shaft 35 of the engine 21 is provided in a state of protruding rearward while rotating around the front-rear axis. The rotating shaft 52 of the cooling fan 24 is flange-connected to the output shaft 35 so as to rotate integrally on the same axis. Therefore, the rotating shaft 52 of the cooling fan 24 extends along the arrangement direction of the engine 21 and the oil cooler 23.

[0045] A partition plate 53 is provided at the front-rear intermediate portion between the muffler 22 and the cooling fan 24. The partition plate 53 is a plate-like member extending in the vertical and horizontal directions. Since the oil cooler 23 is located on the rear side of the cooling fan 24, the cooling fan 24 is disposed between the oil cooler 23 and the partition plate 53. That is, the partition plate 53 is configured to partition the muffler 22 and the oil cooler 23. As shown in FIG. 8, the partition plate 53 is provided wide over substantially the entire area of the lower body region surrounded by the vertical frame member 30 in the view in the vehicle body front-rear direction. The rotation shaft 52 of the cooling fan 24 is provided in a state of penetrating forward and backward through a circular insertion hole 54 formed in the partition plate 53. The partition plate 53 is composed of two left and right plates divided at the left and right intermediate portions, and an arc-shaped notch (insertion hole 54) for passing the rotation shaft 52 is formed at the butting portion of the left and right divided plates 53a and 53b.

[0046] Similar to the oil cooler 23, the partition plate 53 is supported by support rods 55 whose lower ends are erected and supported across the lower front-rear supports 32 on both the left and right sides, and the upper ends are supported by support rods 56 erected and supported across the upper front-rear frame members 31b on both the left and right sides.

[0047] The rotation direction of the cooling fan 24 is set so that cooling air flows from the oil cooler 23 side toward the engine 21 side, and the partition plate � is configured to receive and disperse the cooling air from the cooling fan 24. That is, the forward ventilation direction is set so that the cooling air ventilates from the rear side of the vehicle body toward the front side of the vehicle body.

[0048] In this way, with the engine 21 located on the front side of the machine body and the oil cooler 23 located on the rear side of the machine body, the engine 21, the partition plate 53, and the oil cooler 23 are provided in a state of being arranged along the front-rear direction of the machine body. Also, since the operation control unit 5 is provided at the rear end of the vehicle body, the operation control unit 5 is provided at one end portion (rear end portion) on the side where the oil cooler 23 exists among both side portions in the front-rear direction of the machine body.

[0049] As shown in Figures 5 and 8, side covers 57 are provided on both the left and right sides of the region where the muffler 22, cooling fan 24, and oil cooler 23 are arranged in the front-to-back direction. The side cover 57 has a frame member 57a surrounding it, and the inner portion enclosed by the frame member 57a is provided with a porous portion 57b made of expanded metal. The exhaust gas from the engine 21 discharged from the muffler 22 is easily discharged laterally outward through the porous portion 57b.

[0050] [Another Embodiment] (1) In the above embodiment, the cooling fan 24 is arranged between the oil cooler 23 and the partition plate 53. However, the configuration is not limited to this, and the cooling fan 24 may be arranged on the opposite side of the partition plate 53, that is, on the rear side of the oil cooler 23.

[0051] (2) In the above embodiment, the rotating shaft 52 of the cooling fan 24 is configured to extend along the direction of alignment between the engine 21 and the oil cooler 23. However, instead of this configuration, the rotating shaft 52 may extend in a direction intersecting the above alignment direction, and the cooling fan 24 may be configured to generate cooling air along a direction intersecting the axis of rotation.

[0052] (3) In the above embodiment, the cooling fan 24 is provided so that cooling air flows from the oil cooler 23 side to the engine 21 side, and the partition plate 53 receives and disperses the cooling air. However, instead of this configuration, the cooling fan 24 may be provided so that cooling air flows from the engine 21 side to the oil cooler 23 side, while the partition plate 53 blocks the high-temperature air from the engine 21 and muffler 22.

[0053] (4) In the above embodiment, the muffler 22 is configured to have an exhaust port 40 that discharges exhaust in a direction intersecting the direction in which the engine 21 and the oil cooler 23 are aligned. However, this configuration can be changed to various configurations, such as a configuration in which the exhaust port of the muffler 22 discharges toward the partition plate 53, or a configuration in which it discharges toward the engine 21.

[0054] (5) In the above embodiment, the muffler 22 is provided in a configuration that is aligned with the rear of the vehicle body relative to the engine 21. However, instead of this configuration, the muffler 22 may be provided in a configuration that is aligned with the front of the vehicle body relative to the engine 21, or in a configuration that is aligned with the left and right sides of the vehicle body relative to the engine 21.

[0055] (6) In the above embodiment, the steering control unit 5 is provided at the rear of the vehicle body, but the steering control unit 5 is not limited to the rear of the vehicle body, but may also be provided at the front of the vehicle body, or on the side of the vehicle body, etc.

[0056] (7) In the above embodiment, an oil cooler 23 was given as an example of a cooling unit, but the cooling unit is not limited to an oil cooler 23, and may be a different type of cooling unit, for example, a cooling device for air conditioning (condenser, etc.), a radiator for engine cooling, etc.

[0057] (8) In the above embodiment, a work vehicle was given as an example of a work vehicle for transporting cargo, in which a plurality of running wheels 2 are individually driven and each is supported so as to be able to change the height individually. However, the work vehicle is not limited to such a configuration, and other different types of work vehicles may also be used.

[0058] This invention can be applied to work vehicles equipped with an engine.

[0059] 5 Control Unit 8, 9, 20 Hydraulic Cylinder (Working Device) 10 Hydraulic Pump 21 Engine 22 Muffler 23 Oil Cooler (Cooling Unit) 24 Cooling Fan 40 Outlet 51 Rotating Shaft 52 Partition Plate M Hydraulic Motor (Working Device)

Claims

1. A work vehicle equipped with an engine, a muffler positioned next to the engine and for discharging the engine's exhaust to the outside, a cooling unit, and a partition plate separating the muffler and the cooling unit.

2. The work vehicle according to claim 1, wherein a cooling fan that generates cooling air for the cooling unit is arranged between the cooling unit and the partition plate.

3. The work vehicle according to claim 2, wherein the rotating shaft of the cooling fan extends in the direction of alignment between the engine and the cooling unit.

4. The work vehicle according to claim 3, wherein the cooling fan is provided so that cooling air flows from the cooling unit side toward the engine side, and the partition plate is configured to receive and disperse the cooling air from the cooling fan.

5. The work vehicle according to any one of claims 1 to 4, wherein the muffler has an exhaust port formed therein that discharges exhaust in a direction intersecting the direction in which the engine and the cooling unit are aligned.

6. The work vehicle according to any one of claims 1 to 5, wherein the engine, the partition plate, and the cooling unit are arranged in a manner aligned along the longitudinal direction of the aircraft, and a control unit is provided at one end of both sides of the aircraft in the longitudinal direction on the side where the cooling unit is located.

7. A work vehicle according to any one of claims 1 to 6, comprising: a hydraulic pump driven by the engine; a plurality of work devices operated by hydraulic fluid supplied from the hydraulic pump; and a hydraulic fluid tank for storing the hydraulic fluid, wherein the cooling unit is an oil cooler that cools the hydraulic fluid while circulating the hydraulic fluid stored in the hydraulic fluid tank.

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