JPH05278482A - Power transmission device for vehicle - Google Patents

Abstract

PURPOSE:To downsize a vehicle provided with a pair of left and right oil hydraulic transmissions. CONSTITUTION:A pair of left and right oil hydraulic transmissions 10, 10 able to drive independently left and right crawlers 1, 1 respectively are arranged close to each other, and transmission input shafts projected inward from the hydraulic transmissions 10, 10 are connected to an engine E through endless belts 13, 13 respectively to simplify the power transmitting channel so as to reduce the whole width of a vehicle. Reduction mechanisms and driving shafts 16 of drive wheels 17 are arranged on the outer end portions of transmission output shafts provided in the inner portion of oil hydraulic transmissions 10, 10 coaxially respectively to reduce the whole height of the vehicle, and outer half portions of the oil hydraulic transmissions 10, 10 are arranged in transfer trajectories of the crawlers 1, 1 respectively, to reduce the whole width of the vehicle more.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a pair of hydraulic transmissions arranged adjacent to each other in the left-right direction of a vehicle body, and the transmission input shafts of the respective hydraulic transmissions are connected to a common drive source through transmission means. The present invention relates to a power transmission device for a vehicle in which a transmission output shaft of a hydraulic transmission is connected to drive shafts of left and right drive wheels, respectively.

[0002]

2. Description of the Related Art Conventionally, as a power transmission device for such a vehicle, for example, US Pat. No. 4,809,796, US Pat. No. 4,819,508, or US Pat.
What is described in the specification of No. 76325 is known.

[0003]

By the way, a power transmission device using the above hydraulic transmission is often mounted on a working vehicle. However, such a working vehicle is designed to efficiently perform work in a narrow space. It is desirable to reduce the vehicle body size as much as possible. However, the one described in the above-mentioned U.S. Pat. No. 4,809,796 has the engine disposed above the left and right hydraulic transmissions,
The engine and both hydraulic transmissions are connected by two endless belts wound around a pulley that rotates around an axis extending in the vertical direction of the vehicle body, and the one described in US Pat. No. 4,819,508 is also the same. The engine arranged above and the two hydraulic transmissions are connected by two endless belts wound around a pulley that rotates around an axis extending in the vehicle front-rear direction. If these layouts are adopted, not only will the engine project upwards and the vehicle height will increase, but it will be difficult to reduce the overall width of the vehicle because the left and right hydraulic transmissions cannot be placed close enough. Is.

On the other hand, in the above-mentioned US Pat. No. 3,773,325, an engine is arranged behind the left and right hydraulic transmissions, and a propeller shaft extending from the engine in the longitudinal direction of the vehicle and both hydraulic transmissions are bevel gears. Connected by. The transmission output shafts of both hydraulic transmissions are connected to the left and right axles arranged at a position lower than that via a reduction mechanism. If this layout is adopted, the engine does not project upward, and the vehicle height can be reduced, but there is a problem that the vehicle height becomes higher because the axle is deviated below the mission output shaft.

The present invention has been made in view of the above circumstances, and an object thereof is to reduce the vehicle body size of a vehicle having a pair of hydraulic transmissions as much as possible.

[0006]

In order to achieve the above object, the present invention has a pair of hydraulic transmissions arranged adjacent to each other in the left-right direction of a vehicle body, and the transmission input shafts of the hydraulic transmissions are used as a common drive source. In a power transmission device of a vehicle, wherein the transmission output shaft of each hydraulic transmission is connected to the drive shafts of the left and right drive wheels, the transmission input shaft and the transmission output shaft of the pair of hydraulic transmissions are connected to each other. The first feature is that each of them extends toward the inside and the outside of the vehicle body, and the reduction means and the drive shaft are sequentially connected to the outer end of each mission output shaft toward the outside of the vehicle body.

In addition to the first feature described above, the present invention also provides
A second feature is that at least a part of the decelerating means is arranged in the movement locus of the crawler wound around the drive wheel.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

1 to 3 show an embodiment of the present invention. FIG. 1 is an overall side view of a carrier, FIG. 2 is a sectional view taken along line 2-2 of FIG. 1, and FIG. 3 is a hydraulic transmission on the right side. FIG.

As shown in FIGS. 1 and 2, a walk-behind carrier V traveling by a pair of left and right crawlers 1, 1.
Two main frames 2 and 2 extending in the longitudinal direction of the vehicle body,
A cross member 3 that connects the main frames 2 and 2 to the central part in the left-right direction, a rear frame 4 made of a bent pipe material that is connected to the rear ends of the main frames 2 and 2, and the rear frame 4 are provided. Two cross members 5 and 6 connected in the left-right direction are provided.

At the rear end of the rear frame 4, an engine E as a driving source for traveling is supported in a state of being biased to the right of the center line of the vehicle body, and a crankshaft 7 of the engine E is supported.
Two drive pulleys 8, 8 are fixedly attached to the. A pair of left and right hydraulic transmissions 10, 10 are adjacently supported by a mission support member 9 fixed to the front portion of the rear frame 4, and a mission input shaft 11, which projects from the hydraulic transmissions 10, 10 to face each other, 1
The driven pulleys 12 and 12 are fixed to 1 respectively. Then, the pair of drive pulleys 8 and 8 and the pair of driven pulleys 1
Endless belt 1 as an endless transmission member between 2 and 12
3,13 are wrapped around. Both endless belts 13 and 13 are arranged so as to be distributed to the left and right of the center line of the vehicle body, and are arranged to rotate in a vertical plane extending in the vehicle front-rear direction.

A pair of left and right driven wheels 15 and 15 are attached to a driven shaft 14 disposed in the left and right directions at the front ends of the main frames 2 and 2.
Is rotatably supported, and between the driven wheels 15 and 15 and the drive wheels 17 and 17 fixed to the drive shafts 16 and 16 protruding outward from the hydraulic transmissions 10 and 10,
The crawlers 1 and 1 are respectively wound around. Further, the front and rear two idle wheel shafts 18, 18; 19, 19 extending outward from the left and right main frames 2, 2 have crawler 1, 1
The free wheels 20, 20; 21, 21 that contact the inner circumference of the lower part of the are rotatably supported.

A cargo bed 24 is supported on the upper portions of the main frames 2 and 2 through front and rear brackets 22, 22; 23 and 23, and a handle 26 is provided at the rear end of the handle pipes 25 and 25 extending rearward and upward from the cargo bed 24. , 26 are mounted.

As shown in FIG. 3, the hydraulic transmission 10 disposed on the right side of the vehicle body is provided with an inner casing 28 and an outer casing 29 which are joined with a partition plate 27 interposed therebetween. Ball bearing 3 provided on the inner casing 28
0 and the partition plate 27, the mission input shaft 11 is rotatably supported, the driven pulley 12 is spline-coupled to the inner end of the mission input shaft 11, and the trochoid pump is a charge pump at the outer end thereof. 31
Is installed. The axial piston pump 32 mounted on the mission input shaft 11 is
A rotor 33 that rotates integrally with the rotor 33, a plurality of cylinders 34 formed in the outer circumference of the rotor 33 in the axial direction, and a plurality of cylinders 34 slidably fitted in the cylinders 34 and urged by a spring 35 in the protruding direction. Piston 36 and this piston 36
And a movable swash plate 37 for guiding the tip of the.

On the other hand, the mission output shaft 3 is provided between the ball bearing 38 provided on the inner casing 28 and the partition plate 27.
9 is supported in parallel with the mission input shaft 11, and a brake 52 is attached to the inner end of the mission output shaft 39. The axial piston motor 40 mounted on the mission output shaft 39 includes a rotor 41 that rotates integrally with the mission output shaft 39, a plurality of cylinders 42 axially formed on the outer circumference of the rotor 41, and a cylinder 42 that slides on the cylinder 42. A plurality of pistons 44 that are movably fitted and urged by a spring 43 in the protruding direction, and a fixed swash plate 45 that guides the tip of the pistons 44 are provided. Then, the axial piston pump 32 and the axial piston motor 4
0 is connected to each other through an oil passage (not shown) formed in the partition plate 27.

The ball bearing 4 is mounted on the outer casing 29.
The drive shaft 16 supported via 6 is disposed coaxially with the mission output shaft 39, and the outer end of the mission output shaft 39 is supported by the drive shaft 16 at the inner end via a needle bearing 47. Carrier 4 integrally formed with drive shaft 16
8, a planetary gear 49 is rotatably supported, and this planetary gear 49 meshes with a ring gear 50 fixed to the inner surface of the outer casing 29 and a pinion 51 fixed to the transmission output shaft 39. The carrier 48, the planetary gear 49, the ring gear 50, and the pinion 51 form a reduction mechanism 53. As is apparent from FIG. 2, the speed reduction mechanism 53 housed in the outer half of the hydraulic transmission 10, 10, that is, inside thereof, is disposed by utilizing the internal space of the movement locus of the crawlers 1, 1. As a result, the entire width of the transport vehicle V is reduced.

The hydraulic transmission 10 arranged on the left side of the vehicle body has the same structure which is plane-symmetrical to the hydraulic transmission 10 arranged on the right side of the vehicle body.
The overlapping description will be omitted.

Next, the operation of the embodiment of the present invention having the above construction will be described.

The driving force of the engine E is the driving pulleys 8, 8 provided on the crankshaft 7, the endless belts 13, 13,
And the transmission input shafts 11, 11 of the left and right hydraulic transmissions 10, 10 via the driven pulleys 12, 12.
Be transmitted to. For example, when the transmission input shaft 11 of the hydraulic transmission 10 on the right side rotates, the axial piston pump 32 provided on the transmission input shaft 11 is rotated.
Operates to discharge pressure oil. That is, when the rotor 33 of the axial piston pump 32 rotates together with the piston 36, the tip end of the piston 36 is guided by the movable swash plate 37.
Reciprocates once in the cylinder 34 for each rotation of the mission input shaft 11, and supplies pressure oil to the axial piston motor 40 via an oil passage (not shown) formed in the partition wall plate 27.

When pressure oil is supplied to the cylinder 42 of the axial piston motor 40, the piston 44 is fixed to the fixed swash plate 45.
The piston 44 is pushed toward the fixed swash plate 45.
The reaction force received from the rotor 41 causes the rotor 41 to rotate together with the mission output shaft 39. At this time, by controlling the tilt angle of the movable swash plate 37 of the axial piston pump 32 to change the amount of discharged oil and the discharge direction thereof, the rotation speed and the rotation direction of the mission output shaft 39 can be arbitrarily adjusted. it can. The rotation of the mission output shaft 39 is the pinion 5
1, the planetary gear 49, and the ring gear 50 are transmitted to the drive shaft 16 via the reduction gear mechanism 53, and the right crawler 1 is driven via the drive wheel 17 fixed to the drive shaft 16.

On the other hand, by the same operation, the left hydraulic transmission 10 can drive the left crawler 1 in any direction at any speed. Therefore, by independently controlling the driving of the left and right crawlers 1 and 1, the carrier V can travel straight ahead and turn.

Now, a pair of endless belts 13 and 13 for transmitting the driving force of the engine E to the left and right hydraulic transmissions 10 and 10 are provided on both hydraulic transmissions 10 and 10.
Between the transmissions 10 and 10, the pair of driven pulleys 12 and 12 and the pair of endless belts 13 and 13 are arranged so as to rotate in a vertical plane extending in the vehicle front-rear direction. It is possible to arrange the vehicles close to each other at a narrow interval as much as possible, and since the left and right reduction mechanisms 53, 53 are arranged by utilizing the inner space of the movement locus of the crawlers 1, 1, the carrier vehicle The entire width of V can be reduced. Further, since the engine E is disposed behind the left and right hydraulic transmissions 10, 10 and the reduction mechanisms 53, 53 and the drive shafts 16, 16 are provided coaxially with the transmission output shafts 39, 39, the vehicle height is minimized. It is possible to limit it. Further, the crankshaft 7 of the engine E, the hydraulic transmissions 10, 10
Mission input shafts 11, 11 and mission output shaft 3
9,39 and the drive shaft 1 of the left and right drive wheels 17,17
Since 6 and 16 are arranged in parallel, the power transmission path can be simplified and the power loss can be reduced.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-mentioned embodiments, and various small design changes can be made.

For example, although the carrier V having the crawlers 1 and 1 is illustrated in the embodiment, the present invention is also applicable to a vehicle having the tires as the driving wheels 17 and 17 without the crawlers 1 and 1. You can Further, the position at which the engine E is provided is not limited to the rear side of the hydraulic transmissions 10, 10 and may be the upper side or the front side. In addition, the left and right hydraulic transmissions 10, 10 are respectively associated with a pair of corresponding drive pulleys 8, 8, endless belts 13, 1.
3 and driven by driven pulleys 12, 12,
The transmission input shafts 11 and 11 of both hydraulic transmissions 10 and 10 are integrally connected to form a common drive pulley 8,
It is also possible to drive by the endless belt 13 and the driven pulley 12. Furthermore, instead of the endless belts 13 and 13, it is possible to use an endless chain or a gear, or to drive with a drive shaft and a bevel gear.

[0025]

As described above, according to the first feature of the present invention, the transmission input shafts of the pair of left and right hydraulic transmissions are arranged toward the inner side of the vehicle body so that they face each other. It is possible to reduce the overall width of the vehicle by simplifying the structure of the transmission means that connects the two transmission input shafts to the common drive source between the pair of hydraulic transmissions. Further, since the speed reducing means and the drive shaft are sequentially connected to the outer end of each mission output shaft toward the outside of the vehicle body, the mission output shaft and the drive shaft can be arranged at the same height to reduce the total height of the vehicle. ..

Further, according to the second aspect of the present invention, since at least a part of the speed reducing means is arranged by utilizing the inner space of the movement locus of the crawler wound around the drive wheels, the overall width of the vehicle is further reduced. Can be made

[Brief description of drawings]

FIG. 1 is an overall side view of a carrier (a sectional view taken along line 1-1 of FIG. 2).

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is an enlarged sectional view of the hydraulic transmission on the right side.

[Explanation of symbols]

 1 Crawler 10 Hydraulic Transmission 13 Endless Belt (Transmission Means) 16 Drive Shaft 17 Drive Wheels 53 Reduction Gear E Engine (Drive Source)

Claims (2)

[Claims] 1. A pair of hydraulic transmissions (10).
Are arranged adjacent to each other in the left-right direction of the vehicle body, and the transmission input shaft (11) of each hydraulic transmission (10) is connected to a common drive source (E) via a transmission means (13). 10) The mission output shaft (39) of the left and right drive wheels (17) drive shaft (16)
In a power transmission device of a vehicle connected to each of the transmissions, the transmission input shaft (11) and the transmission output shaft (39) of the pair of hydraulic transmissions (10) are extended toward the inside and the outside of the vehicle body, respectively. A power transmission device for a vehicle, characterized in that a speed reducer (53) and the drive shaft (16) are sequentially connected to an outer end of a shaft (39) toward the outside of the vehicle body. 2. The vehicle according to claim 1, characterized in that at least a part of the speed reducing means (53) is arranged in a movement locus of the crawler (1) wound around the drive wheel (17). Power transmission device.