JPH0479855B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to the configuration of an HST integrated axle drive device used as a variable speed drive device for an axle in a traveling vehicle such as a tractor.

(b) Prior Art Conventionally, the technology of providing an HST transmission attached to a transmission case of an axle is known.

For example, as in US Pat. No. 4,513,834.

However, in this technology, the HST transmission is attached to the outside of the transmission case, and the
Since the HST integrated axle drive system cannot be constructed small and compact, and the direction of the pump shaft of the HST transmission is protruded horizontally forward,
When equipped with a vertical crankshaft engine, there was a problem in that it was difficult to transmit power.

(c) Problems to be Solved by the Invention The present invention solves the above-mentioned conventional problems, and separates the hydraulic pump P and hydraulic motor of the HST transmission into the variable drive case of the axle. The transmission case is configured to be compact by being integrated with the transmission case, and the pump shaft of the hydraulic pump P is a vertical shaft, so that the power is transmitted from the engine E having a vertical crankshaft by the horizontally hung V-belt 5. This made communication possible.

(d) Means for Solving the Problems The objects of the present invention are as described above, and the configuration for achieving the objects will now be explained.

The transmission case that drives the axles 6L and 6R at variable speeds is roughly divided into two on the left and right sides in the direction of travel, and one side is for the axle 6L.
The other is a hydraulic pump case 10 integrally constructed with an axle housing supporting the axle 6R, and a hydraulic motor case 11 integrally constructed with the axle housing of the axle 6R.

(E) Embodiment The object and structure of the present invention are as described above. Next, the structure of the embodiment shown in the attached drawings will be explained.

Fig. 1 is an overall side view of a tractor equipped with an HST integrated axle drive system of the present invention, Fig. 2 is a plan cross-sectional view of the HST integrated axle drive system of the present invention, and Fig. 3 is a line A--A in Fig. 2. A sectional view, FIG. 4 is an enlarged sectional view of the hydraulic pump P, FIG. 5 is an enlarged sectional view of the hydraulic motor M, and FIG. 6 is an overall perspective view of the HST integrated axle drive device.

The overall structure of a tractor equipped with a mower device R in FIG. 1 will be explained.

The aircraft body is supported between front wheels 1, which are driving wheels, and rear wheels 2, which are steering wheels, and an engine E with a vertical crankshaft protruding from the aircraft body is mounted.

An output pulley 3 is fixed to the vertical crankshaft of the engine E. Power is transmitted from the output pulley 3 to an input pulley 4 fixed to a pump shaft 9 of a hydraulic pump P of the HST integrated axle drive system via a V-belt 5 stretched horizontally.

The axles 6L and 6R of the tractor are horizontally protruded left and right, whereas the pump shaft 9 of the hydraulic pump P is arranged vertically parallel to the vertical crankshaft.

The mower device R is a front mower device R as shown in Fig. 1.
It can also be used as a Mitsudmor device R' and can be mounted on the abdomen of a tractor.

Next, the specific configuration of the HST integrated axle drive device will be explained with reference to FIGS. 2 and 3.

In the present invention, the transmission case that supports the axles 6L and 6R and drives the power of the engine E while changing the speed is a flat transmission case arranged horizontally as shown in FIG.

The transmission case is divided into right and left halves in the direction of travel, and one left side in the direction of travel is constructed as a hydraulic pump case 10 that is integrally formed with an axle housing that supports the axle 6L.

The other is constructed in a hydraulic motor case 11 that is integrally constructed with the axle housing of the axle 6R.

And on the hydraulic pump case 10 side, there is an axle 6
The axle housing part that supports L and the hydraulic pump P
In addition, the joint part with the hydraulic motor case 11 side is configured as the joint surface oil passage wall 10b, and the joint surface oil passage wall 10b
An oil passage 10a from the hydraulic pump P to the hydraulic motor M is bored in the portion 0b.

Also, on the side of the hydraulic motor case 11 is an axle 6R.
In addition to the axle housing and the hydraulic motor M section that support the axle housing and the hydraulic motor M section, a gear reduction device is also provided between the motor shaft 24 and the ring gear 7 of the differential gear device.

The case of hydraulic pump P is hydraulic pump case 1.
The pump shaft 9 is integrally constructed with the pump shaft 9 and has an open upper part so that the pump shaft 9 is vertically disposed, and power is transmitted by the pump shaft 9. A swash plate rotation shaft 8 protrudes from the hydraulic pump case 10.
A swash plate 25 inside the hydraulic pump P is rotated by the swash plate rotating shaft 8, so that the hydraulic motor M can be continuously variable in forward, neutral, and reverse directions.

Then, the pressure oil discharged from the hydraulic pump P is transferred to the hydraulic motor M via the oil passage 10a bored in the joint surface oil passage wall 10b in the hydraulic pump case 10.
The rotor 22 is guided in a cylinder formed by the rotor 22.

The rotation of the rotor 22 of the hydraulic motor M is transmitted to a motor shaft 24, from a small diameter gear 13 fixed on the motor shaft 24 to a large diameter gear 14 on a reduction shaft 18.

The other small diameter gear 15 of the reduction shaft 18 meshes with the rig gear 7 of the differential gear device.

The differential gear device does not include a gear case, and a hole in the inner diameter of the ring gear 7 also serves as the gear case. A pinion shaft 1 is attached to the inner diameter of the ring gear 7.
7 is fixed, and opposing pivot holes for the inner ends of the left and right axles 6L, 6R are formed in the center of the pinion shaft 17. The pinions 19 and 20 loosely fitted to the pinion shaft 17 mesh with the differential side gears 21L and 21R, and the axle 6 is connected to the differential side gears 21L and 21R.
The splines at the inner ends of L and 6R are engaged and fitted.

Next, this will be explained with reference to FIGS. 3, 4, and 5.

As shown in FIG. 3, in the present invention, the axes of the hydraulic motor M and the hydraulic pump P are disposed orthogonal to each other. The power transmission direction is bent at 90 degrees in the oil passage 10a that sends pressure oil from the hydraulic pump P to the hydraulic motor M.

The hydraulic pump P has a rotor 27 driven by a pump shaft 9 fitted with a spline, and a piston 26 is fitted into a cylinder hole opened at a constant interval on the rotor 27 so as to be able to protrude and retreat. be.

When the rotor 27 is driven by the rotation of the pump shaft 9, the tip of the protruding portion of the piston 26 is in contact with the swash plate 25, which is rotated by the swash plate rotation shaft 8, so that pressure oil is not discharged. The amount and direction of discharge are changed.

The pressure oil passes through the oil passage 10a of the joint surface oil passage wall 10b and is sent into a cylinder opened in the rotor 22 of the hydraulic motor M.

A fixed swash plate 16 is fixed to the swash plate seat 11a of the hydraulic motor case 11 on the hydraulic motor M side, and the tip of the piston 23 is always in contact with the fixed swash plate 16 of the swash plate seat 11a. Therefore, when the piston 23 is pressed against the inclined surface of the fixed swash plate 16 by pressure, it generates a rotational force that rotates the rotor 22 in the forward and backward directions.

FIG. 6 shows an overall perspective view of the HST integrated axle drive device of the present invention.

(F) Effects of the Invention Since the present invention is configured as described above, it has the following effects.

First, since the hydraulic pump P and the hydraulic motor M are housed in the transmission case that supports, shifts, and drives the axles 6L and 6R, the axle drive device can be configured compactly. Depending on the shape of the tractor, the HST integrated axle drive device can be placed horizontally, vertically, front to back reversed, or placed at the rear wheel. It is something.

Second, when a vertical crankshaft type engine E is installed, it is necessary to change the direction of power transmission from the vertical axis to the horizontal axis of the axles 6L and 6R. The direction of the hydraulic motor M is changed from the hydraulic pump P to the hydraulic motor M, whereas in the case of the present invention, the direction of the
The structure is simple because it can be constructed by bending the oil passage 10a of the joint surface oil passage wall 10b leading to the oil passage 10b by 90 degrees.

Thirdly, without constructing a large case as a transmission case, the hydraulic pump P is housed in the protruding parts of the axle housings of the axles 6L and 6R on one side, and the hydraulic motor M is housed on the other side. , HST is about the size of a conventional axle case.
It was possible to construct an integrated axle drive device.

[Brief explanation of drawings]

Fig. 1 is an overall side view of a tractor equipped with an HST integrated axle drive system of the present invention, Fig. 2 is a plan cross-sectional view of the HST integrated axle drive system of the present invention, and Fig. 3 is a line A--A in Fig. 2. A sectional view, FIG. 4 is an enlarged sectional view of the hydraulic pump P, FIG. 5 is an enlarged sectional view of the hydraulic motor M, and FIG. 6 is an overall perspective view of the HST integrated axle drive device. P...Hydraulic pump, M...Hydraulic motor, E...
... Vertical crankshaft engine, 8 ... Swash plate rotation shaft, 9 ... Pump shaft, 10 ... Hydraulic pump case, 11 ... Hydraulic motor case.

Claims (1)

[Claims] 1 The transmission case that drives the axles 6L and 6R at variable speeds is roughly divided into two on the left and right in the direction of travel, and one side is connected to the axle 6.
An HST integrated axle drive device characterized in that a hydraulic pump case 10 is integrally constructed with an axle housing that supports an axle L, and the other is a hydraulic motor case 11 that is integrally constructed with an axle housing of an axle 6R.