JPH05193379A - Axle drive device - Google Patents

Abstract

PURPOSE:To narrow a lateral width of a housing small, and compact the device by disposing an output rotation body on the opposite side of a motor installation part, and disposing a pump installation part and an axle input gear almost at a center of the width of a vehicle. CONSTITUTION:A center section 4 is formed in an L-shaped form, an upper surface is set as a pump installation part 4a where a hydraulic pump P is mounted, a side surface is set as a motor installation part 4b where a hydraulic motor M is supported, and the hydraulic motor M and an output rotation body 14 are disposed in an allowance space at an undersurface of the center section 4. The pump installation part 4a and an input gear 17 for axles 1L, 1R are disposed almost at a center of the width of a vehicle. A lateral width of a housing can thus be set small, and it can be compact, thereby a frame width of the vehicle can be narrowed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an arrangement of a hydraulic continuously variable transmission and an output rotary member in a housing of an axle drive unit mounted on a traveling work vehicle.

[0002]

2. Description of the Related Art Conventionally, a technique relating to an axle drive device in which a hydraulic pump, a hydraulic motor and a center section are arranged in a housing has been publicly known. For example,
U.S. Pat. No. 4,932,209 and U.S. Pat. No. 4,986.
As disclosed in Japanese Patent Application No. 073.

[0003]

However, in the above-mentioned prior art, since the arrangement of the hydraulic pump and the hydraulic motor is eccentric in the housing, the width of the housing becomes wider in the direction of the axle. Since the position of the input shaft from the engine is not in the center position of the traveling work vehicle, the position of the differential gear device 21 is also displaced from the center of the machine body,
The problem was that the left and right axles had different lengths. The present invention solves the above-mentioned problems of the prior art.

[0004]

The problems to be solved by the present invention are as described above, and the means for solving the problems will be described below. That is, the center section 4 having a shape in which the pump mounting portion 4a and the motor mounting portion 4b are orthogonal to each other is housed in the housing of the axles 1L and 1R, the hydraulic pump P and the hydraulic motor M are mounted, and the hydraulic pump P is a belt transmission device. In the axle drive device in which the output rotor 14 of the hydraulic motor M is interlockingly coupled to the engine E via the input gear 17 of the axles 1L and 1R, the output rotor 14 is provided on the opposite side of the motor mounting portion 4b. The pump mounting portion 4a and the axle 1 are arranged as well.
The L and 1R input gears 17 are arranged in the housing so as to be arranged substantially at the center in the width direction of the vehicle.

[0005]

[Operation] Next, the operation will be described. Airframe frame 12L / 1
Power is transmitted from the engine E mounted on the 2R to the input shaft 5 via a belt, the hydraulic pump P is driven by the input shaft 5 to discharge pressure oil, and the hydraulic motor M is driven by the pressure oil. The rotation from the output rotating body 14 is transmitted to the axles 1L and 1R via the input gear 17 and the differential gear device 21, and the rear wheels 2
It drives 4/24. In such an operation, the present invention particularly configures the center section 4 in a "" shape, mounts the hydraulic pump P on the upper surface as the pump mounting portion 4a, and supports the hydraulic motor M on the side surface as the motor mounting portion 4b. Since the hydraulic motor M and the output rotary body 14 are arranged in the spare space on the lower surface of the center section 4, the width can be made narrower than that of the conventional axle drive device. Further, the position of the input shaft 5 can be arranged at the center position of the axles 1L and 1R having the same length on the left and right sides.

[0006]

EXAMPLES Next, examples will be described. 1 is a plan view of a traveling work vehicle equipped with an axle drive device of the present invention, FIG. 2 is a side view thereof, and FIG. 3 is a plan view of the axle drive device of the present invention with an upper half half 2 removed 4 is also AA of FIG.
FIG. 5 is a sectional view taken along the arrow BB in FIG. 3, and FIG. 6 is a plan view showing another embodiment of the axle drive device of the present invention.
7 is a sectional view taken along the line CC of FIG. 6, and FIG. 8 is the same as D of FIG.
-D arrow sectional view, FIG. 9 is a perspective view of the center section 4 of the embodiment of FIGS. 3, 4, and 5, and FIG. 10 is FIG. 6, FIG. 7, and FIG.
3 is a perspective view of the center section 4 of the embodiment of FIG.

This will be described with reference to FIGS. 1 and 2. The axle drive device of the present invention is fixed from below to the lower rear part of the body frame 12 of the traveling work vehicle. Also the body frame 12
A vertical type engine E is mounted above the front of the L / 12R. A belt 26 is wound around a pulley 25 fixed to the crank shaft of the engine E, and power is transmitted to a pulley 27 ′ of a counter shaft 29. The counter shaft 29 has an expansion joint 29 'at its lower end and is connected to the input shaft of the mower device MR. The belt 28 is wound around the pulley 27 above the counter shaft 29, so that the input shaft 5
Power is transmitted to the pulley 20 of.

The front wheels 23, 23 of the traveling work vehicle are steering wheels, and the rear wheels 24, 24 are driving wheels. The rotation after shifting by the hydraulic continuously variable transmission inside the axle drive device is transmitted from the differential gear device 21 to the axles 1L and 1R so that the rear wheels 2
Driving 4/24.

Next, the configuration of the first embodiment will be described with reference to FIGS. 3, 4 and 5. The housing is the upper half 2 of the housing
And the lower half 3 of the housing can be separated vertically by a horizontal joint surface on the axis of the axles 1L and 1R. A bearing is sandwiched on the horizontal joint surface of the upper half half 2 and the lower half half 3 to support the axle shafts 1L and 1R and the output shaft 6. Also, as shown in FIG. 5, on the inner surface of the upper half 2 of the hanging,
The mounting surface 2a of the center section 4 is formed on the inner surface above the horizontal joint surface. The extension mounting surface of the pump mounting portion 4a of the center section 4 is fixed to the mounting surface 2a from below.

As shown in FIG. 3, the center section 4 is formed in a "" shape, and has a pump mounting portion 4a on its upper surface and a motor mounting portion 4b on its side surface. A cylinder block 7 constituting the hydraulic pump P is rotatably supported on the pump mounting portion 4a, and the cylinder block 7 and the input shaft 5 are in an engaged state. A plurality of cylinder holes are opened in the cylinder block 7, and a pump piston 34 is fitted in the cylinder hole so that the pump piston 34 can move in and out. The upper end portion of the pump piston 34 contacts the lower surface of the movable swash plate 10 to supply the forward / reverse pressure oil to the hydraulic pump P.
To discharge to the hydraulic motor M through an oil passage forming a closed circuit in the center section 4.

The motor mounting portion 4b of the center section 4
The hydraulic motor M is supported by the portion. A cylinder block 8 constituting the hydraulic motor M is slidably and rotatably supported by the motor mounting portion 4b, and the output shaft 6 and the cylinder block 8 are engaged with each other. A plurality of cylinder holes are opened in the cylinder block 8, and a motor piston 35 is fitted in the cylinder hole so that the motor piston 35 can be retracted and retracted. The right end of the motor piston 35 contacts the fixed swash plate 11, and the pushing force of the motor piston 35 pushed by the pressure oil sent to the cylinder hole is converted into the rotational force of the cylinder block 8. The displacement of the hydraulic motor M is set to be larger than that of the hydraulic pump P so that the hydraulic motor M is decelerated hydraulically.

A brake disc 13 is fixed to the end of the output shaft 6 on the side of the fixed swash plate 11, and the disc pressing cam body integrally formed with the brake lever 19 presses the brake disc 13. This constitutes a braking device for the axle drive device. In the embodiment shown in FIGS. 3, 4 and 5, the output shaft 6 of the hydraulic motor M is projected to the side opposite to the fixed swash plate 11 and penetrates the wall surface of the motor mounting portion 4b of the center section 4, The output rotary body 14 is provided so as to project into the empty space below the pump mounting portion 4a of the center section 4 configured in a "" shape. An input gear 17 of the differential gear device 21 meshes with the output rotary body 14. Power is transmitted to the differential gear device 21 by the input gear 17, and differential rotation is transmitted to the axles 1L and 1R. Figure 9
Discloses a perspective view of the center section 4 for use in the embodiment shown in FIGS. 3, 4 and 5.

Next, the embodiment shown in FIGS. 6, 7, 8 and 10 will be described. The second embodiment is also the same in that the center section 4 is formed in a "" shape. As clearly shown in FIG. 7, the output rotor 14 is not arranged in the space formed below the pump mounting portion 4a of the center section 4, but the cylinder block 8 of the hydraulic motor M is arranged therein. The output shaft 6 penetrates through the motor mounting portion 4b of the center section 4 and projects to the opposite side, and the output rotating body 14 is provided on the projecting portion. The output rotary body 14 does not directly mesh with the input gear 17 of the differential gear device 21 as in the first embodiment, but first, the gear 16 on the counter shaft 15 and the output rotary body 1 are engaged.
4 and the small diameter gear 18 on the counter shaft 15
Is engaged with the input gear 17 of the differential gear device 21. This is because the capacity of the hydraulic motor M and the capacity of the hydraulic pump P are set to be substantially equal.

It is the same in that the center section 4 is attached to the inner surface of the upper half 2 of the housing from below on the mounting surface 2a. As shown in FIG. 10, in the center section 4 of the second embodiment, the motor mounting portion 4b is formed in the vertical portion of the lower surface of the pump mounting portion 4a.

[0015]

Since the present invention is configured as described above, it has the following effects. That is, first, the input shaft 5, which is the pump shaft, is located substantially in the center of the vehicle, and the dead space on the back side of the pump mounting portion 4a is set to the hydraulic motor M.
Alternatively, since it can be used at the place where the output rotary body 14 is installed, the width of the housing in the left-right direction can be narrowed to make it compact, and the frame width of the vehicle can be made narrower. Of.

Secondly, since the position where the input shaft 5 and the differential gear device 21 are arranged can be arranged at the center position on the left and right of the traveling work vehicle, the axles 1L and 1R projecting left and right from the differential gear device 21 can be arranged. Can be the same length,
The left and right axles can share the same parts.

[Brief description of drawings]

FIG. 1 is a plan view of a traveling work vehicle equipped with an axle drive device of the present invention.

FIG. 2 is a side view thereof.

FIG. 3 is a plan view of the axle driving device of the present invention with the upper half half 2 removed.

FIG. 4 is a sectional view taken along line AA of FIG.

FIG. 5 is a sectional view taken along line BB of FIG.

FIG. 6 is a plan view showing another embodiment of the axle driving device of the invention.

7 is a cross-sectional view taken along the line CC of FIG.

FIG. 8 is a sectional view taken along the line DD of FIG.

FIG. 9 is a perspective view of the center section 4 of the embodiment shown in FIGS. 3, 4, and 5;

10 is a perspective view of the center section 4 of the embodiment shown in FIGS. 6, 7, and 8. FIG.

[Explanation of symbols]

 P Hydraulic pump M Hydraulic motor 1L, 1R Axle 2 Upper half of hanging 3 Lower half of hanging 4 Center section 4a Pump mount 4b Motor mount 5 Input shaft 6 Output shaft 7 Cylinder block 8 Cylinder block 14 Output rotor 17 Input gear 21 Differential gear device

Claims (1)

[Claims] 1. A center section 4 having a shape in which a pump mounting portion 4a and a motor mounting portion 4b are orthogonal to each other is housed in a housing of an axle 1L / 1R, and a hydraulic pump P and a hydraulic motor M are mounted, and the hydraulic pump P is a belt. The output rotor 14 of the hydraulic motor M is connected to the engine E via a transmission device.
In the axle drive device in which the above is connected to the input gears 17 of the axles 1L and 1R, the output rotor 14 is arranged on the side opposite to the motor attachment portion 4b, and the pump attachment portion 4a and the input gears 17 of the axles 1L and 1R are An axle drive device characterized in that it is arranged in the housing so as to be arranged substantially at the center in the width direction of the vehicle.