JPH06211060A - Hst-integrated axle driving device - Google Patents

Abstract

PURPOSE:To prevent the outer face of an axle case from being soiled without the decrease of operating oil even in the case of pressure oil leaking by enclosing the hydraulic pump and hydraulic motor of an HST driving device inside of a half-divided axle case, and allow the position of a pump shaft to be changed in relation to the axle case since only the pump case and the hydraulic pump can be replaced. CONSTITUTION:An axle case 11 supporting axles 6L, 6R protrusively is formed of a center plate 10 and half-divided axle cases 11L, 11R respectively fitted to both side faces of the center plate 10. A hydraulic pump and a hydraulic motor with a motor shaft 24 connected to a mechanical reduction gear are assembled to the side face of the center plate 10, and an oil passage for communicating the inlet-outlet port of the hydraulic pump with the inlet-outlet port of the hydraulic motor is bored in the center plate 10. The half-divided axle case 11L is fitted in such a way as to cover the hydraulic pump and hydraulic motor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an HST used as a speed change drive device for an axle in a traveling vehicle such as a tractor.
The present invention relates to the structure of an integrated axle drive device.

[0002]

2. Description of the Related Art Conventionally, a technique in which an HST transmission is provided by being attached to a transmission drive case for an axle has been known. For example, West German Patent Application Publication No. 2052
No. 084 and U.S. Pat. No. 4,513,834. However, West German Patent Application Publication No. 205208
In the specification of No. 4, two hydraulic motors are arranged, but the position of the hydraulic pump is not clear. In addition, the mission case is set to 2 by the center plate 10.
The divided structure is not disclosed. Further, in the specification of US Pat. No. 4,513,834, the HST transmission is attached to the outside of the mission case, and
Since the ST-integrated axle drive cannot be made compact and compact, and the direction of the pump shaft of the HST transmission is projected horizontally forward, when a vertical crankshaft type engine is installed, The problem is that it becomes difficult to transmit power.

[0003]

DISCLOSURE OF THE INVENTION The present invention is complicated because it is not necessary to drill an oil passage connecting the hydraulic pump P and the hydraulic motor M in the half-split axle cases 11L and 11R obtained by dividing the axle case 11. It is possible to concentrate hydraulic-related parts that need to be machined only on the center plate 10. Also, both the hydraulic pump P and the hydraulic motor M, which cause leakage of pressure oil, have the same half split axle case 11L. Since it is inside the half-split axle case 11L even if pressure oil leaks, the hydraulic oil does not decrease, and it leaks into the half-split axle case 11L and 11R. In this case, the outer surface of the axle case 11 is not contaminated and only the pump case 12 and the hydraulic pump P can be replaced. Therefore, the position of the pump shaft can be changed with respect to the axle case. It than is configured to allow.

[0004]

The object of the present invention is as described above. Next, the structure for achieving the object will be described.
That is, the axle case 11 that projects and supports the axles 6L and 6R.
The center plate 10 and the center plate 10
Half axle case 11L attached to both sides of
11R, which is attached to one side surface of the center plate 10 has a half axle case 11R, and the axles 6L, 6
A differential gear device for differentially connecting R and a gear reduction device are arranged, and a hydraulic motor M having a motor shaft 24 connected to the gear reduction device on the other side surface of the center plate 10 and a hydraulic motor M. Hydraulic pump P that supplies pressure oil
And an oil passage for connecting the inlet / outlet port of the hydraulic pump P and the inlet / outlet port of the hydraulic motor M to form a closed circuit are bored in the center plate 10.

A half-split axle case 11L on the other side of the center plate 10 is attached so as to cover the hydraulic pump P and the hydraulic motor M.

A half-split axle case 11L on the other side of the center plate 10 is attached so as to cover only the hydraulic motor M, and the hydraulic pump P is attached to the pump case 1.
It is covered by 2.

[0007]

[Operation] Next, the operation will be described. That is, it is not necessary to drill an oil passage connecting the hydraulic pump P and the hydraulic motor M in the half-split axle cases 11L and 11R, which are obtained by dividing the axle case 11, and there are no hydraulic-related parts that require complicated machining. It is possible to concentrate only on the center plate 10. Also,
Since the hydraulic pump P and the hydraulic motor M, which leak pressure oil, can be housed inside the same half-split case 11L, even if the pressure oil leaks, the half-split case 1
Since it is inside 1 L, the hydraulic oil does not decrease. Further, when the inside of the half-split axle cases 11L and 11R leaks, the outer surface of the axle case 11 is not contaminated. Further, since only the pump case 12 and the hydraulic pump P can be replaced, the position of the pump shaft can be changed with respect to the axle case.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The object and structure of the present invention are as described above. Next, the structure of the embodiment shown in the accompanying drawings will be described. FIG. 1 is an overall side view of a tractor equipped with the HST-integrated axle drive device of the present invention, FIG. 2 is a plan sectional view of the HST-integrated axle drive device of the present invention, and FIG. 3 is a hydraulic pump P of a half-split axle case. FIG. 4 is a rear sectional view of a portion of the hydraulic pump P, and FIG. 5 is an HS sectional view of the embodiment of FIG.
FIG. 6 is an overall perspective view of the T-integrated axle drive device, and FIG. 6 is an overall perspective view of the HST-integrated axle drive device of the embodiment of FIG.

The overall structure of the tractor equipped with the mower device R will be described with reference to FIG. Front wheel 1 that is the driving wheel
An engine E having a vertical crankshaft projecting thereon is mounted between the rear wheels 2 which are steering wheels. An output pulley 3 is fixed to the vertical crankshaft of the engine E. Power is transmitted to the input pulley 4 fixed to the pump shaft 9 of the hydraulic pump P of the HST-integrated axle drive device via the V belt 5 stretched horizontally from the output pulley 3.

The axles 6L and 6R of the tractor are projected horizontally to the left and right, whereas the pump shaft 9 of the hydraulic pump P is arranged vertically in parallel with the vertical crankshaft. The mower device R can be used as the front mower device R as shown in FIG. 1, or can be attached to the abdomen of the tractor as the mid mower device R ′.

Next, a specific structure of the HST-integrated type axle drive device in the embodiment of FIG. 2 will be described. The axle case 11 is roughly divided into left and right in the traveling direction into a half case,
One half-split axle case is a left half-split axle case 11L that supports the axle 6L and the hydraulic motor M, and the other half-split axle case is the right that houses the differential gear device and the gear reduction device in the portion that supports the axle 6R. A half axle case 11R is formed by joining the two with the center plate 10 sandwiched at the center.

Then, the axle case 11 is bulged in the front-rear horizontal direction at the portion where the differential gear device is arranged,
The gear reduction device is housed in this portion.
Further, an essential part of the present invention is that the hydraulic motor M is fitted on the outer circumference of the axle 6L inside the left half-split axle case 11L. The hydraulic motor M is formed concentrically with the axle 6L, and a cylindrical motor shaft 24 is loosely fitted to the outer periphery of the axle 6L, and a spline formed on the outer periphery of the motor shaft 24 is provided with an inner periphery of the rotor 22. The spline is engaged and fitted.

The swash plate 2 is also attached to the left half axle case 11L.
5 also constitutes the swash plate seat 11a, and the tip of the piston 23 inserted in the cylinder hole of the rotor 22 contacts the fixed swash plate 16. Then, the piston 23 is sequentially projected by the pressure oil sent from the hydraulic pump P, and the pressing surface of the fixed swash plate 16 is pushed, whereby a rotational force is generated in the rotor 22. The rotational force is transmitted to the motor shaft 24 configured as a cylinder shaft, and the motor shaft 24 penetrates through the center plate 10 and the right half split axle case 1
The power is transmitted to the gear reduction device by being projected into 1R.

The rotor 22 of the hydraulic motor M is in contact with the center plate 10, and the center plate 1
Through the oil passage 10a bored in the hydraulic motor M
The pressure oil sent to the side is guided into the cylinder hole of the rotor 22. The hydraulic pump P is shown in FIG.
In the embodiment, the center plate 10 sandwiched between the left half-split axle case 11L and the right half-split axle case 11R.
The left half axle case 11L is attached to the side surface of the hydraulic pump case 12 in a state where the left half axle case 11L is not extended.

The pressure oil discharged from the hydraulic pump P in the hydraulic pump case 12 is supplied from the oil passage a of the hydraulic pump case 12 to the left half split axle case 11L and the right half split axle case 1.
Oil passage 10 of center plate 10 sandwiched between 1R
Oil is sent to the cylinder hole of the hydraulic motor M via a. Since it is the vertical crankshaft type engine E, the pump shaft 9 needs to be arranged vertically, and conversely, the axles 6L and 6R are projected horizontally, so that the motor shaft 24 is arranged horizontally. The power transmission in the orthogonal state between the hydraulic motor M and the oil passage 1 and the oil passage 1 is performed.
It is simply constructed by bending the portion 0a by 90 degrees.

Power is transmitted to the hydraulic pump P by a pump shaft 9. Then, the swash plate rotating shaft 8 is provided so as to project from the hydraulic pump case 12, and the swash plate 25 inside the hydraulic pump P is rotated by the swash plate rotating shaft 8 to move the hydraulic motor M forward, neutral, or reverse. It is possible to continuously change gears. Further, the rotation of the rotor 22 of the hydraulic motor M causes the rotation of the motor shaft 24.
Is transmitted to the Deagiff device through the gear reduction device described above. The gear reduction device includes the motor shaft 24
The small-diameter gear 13 fixed on the top is transmitted to the large-diameter gear 14 on the reduction shaft 18.

Another small-diameter gear 15 of the reduction shaft 18 is constituted by meshing with the ring gear 7 of the differential gear device, and as a whole, decelerates from the motor shaft 24 on the axle 6L to the reduction shaft 18, and The power transmission is configured to return to the differential gear device on the axle 6R. The diff gear device does not have a gear case, and the inner diameter hole of the ring gear 7 also serves as a gear case. The pinion shaft 17 is fixed to the inner diameter of the ring gear 7, and the center portion of the pinion shaft 17 forms opposing pivot support holes at the inner ends of the left and right axles 6L and 6R.
The pinions 19 and 20 loosely fitted to the pinion shaft 17 mesh with the differential side gears 21L and 21R, and the splines at the inner ends of the axles 6L and 6R are engaged and fitted into the differential side gears 21L and 21R.

Next, the embodiment shown in FIG. 3 will be described. In this embodiment, the hydraulic pump P attached to the center plate 10 is not covered with another hydraulic pump case 12, but the left half split axle case 11L is extended so as to serve as a hydraulic pump case. -ing In the case of this embodiment as well, the center plate 10 is arranged, and the same point that pressure oil is sent from the hydraulic pump P to the hydraulic motor M via the oil passage 10a inside the center plate 10. is there.

Next, the structure of the hydraulic pump P will be described with reference to FIG. The hydraulic pump P is spline-fitted with a rotor 27 driven by a pump shaft 9.
The piston 26 is fitted in the cylinder hole that is opened at a certain interval above and is capable of projecting and retracting. When the rotor 27 is driven by the rotation of the pump shaft 9,
Since the tip of the protruding portion of the piston 26 is in contact with the swash plate 25 rotated by the swash plate rotation shaft 8, the pressure oil is discharged by changing the discharge amount and the discharge direction. 5 and 6, there is shown an overall perspective view of the HST-integrated axle drive device of the embodiment shown in FIGS.

[0020]

Since the present invention is constructed as described above, it has the following effects. That is, as in claim 1,
Left and right half-split axle cases 11L. 1 in which axle cases 11 projecting and supporting the axles 6L and 6R are attached to the center plate 10 and both side surfaces of the center plate 10, respectively.
The right half split axle case 11R, which is configured by 1R and is attached to one side surface of the center plate 10, has the axles 6L and 6L.
A differential gear device for differentially connecting R and a gear reduction device are arranged, and a hydraulic motor M having a motor shaft 24 connected to the gear reduction device on the other side surface of the center plate 10 and a hydraulic motor M. Hydraulic pump P that supplies pressure oil
The axle case 11 is divided because the center plate 10 is provided with an oil passage for connecting the inlet / outlet port of the hydraulic pump P and the inlet / outlet port of the hydraulic motor M to form a closed circuit. A hydraulic pump P and a hydraulic motor M are provided in the half-axle cases 11L and 11R.
It was not necessary to drill an oil passage for connecting the above, and hydraulic-related parts requiring complicated processing could be concentrated only on the center plate 10.

Since the half-split axle case 11L on the other side surface of the center plate 10 is mounted so as to cover the hydraulic pump P and the hydraulic motor M as in claim 2, the hydraulic pump causes leakage of pressure oil. Both P and hydraulic motor M can be housed inside the same half-split axle case 11L, so that even if pressure oil leaks, half split axle case 11
Since it is inside L, the hydraulic oil does not decrease. Further, when the inside of the half-split axle cases 11L and 11R leaks, the outer surface of the axle case 11 is not contaminated.

As described in claim 3, the half-split axle case 11L on the other side surface of the center plate 10 is connected to the hydraulic motor M.
Since only the pump case 12 and the hydraulic pump P can be replaced, the position of the pump shaft is changed with respect to the axle case. You can do it.

[Brief description of drawings]

FIG. 1 is an overall side view of a tractor equipped with an HST-integrated axle drive device of the present invention.

FIG. 2 is a plan sectional view of an HST-integrated axle drive device of the present invention.

FIG. 3 is a plan sectional view of an embodiment in which a hydraulic pump P is arranged inside a half axle case.

FIG. 4 is a rear sectional view of a hydraulic pump P.

5 is an overall perspective view of the HST-integrated axle drive device of the embodiment of FIG.

6 is an overall perspective view of an HST-integrated axle drive device of the embodiment of FIG.

[Explanation of symbols]

 P hydraulic pump M hydraulic motor E vertical crankshaft type engine 8 swash plate rotating shaft 9 pump shaft 10 center plate 11 axle case 11L left axle case 11R right axle case 12 hydraulic pump case

Claims (3)

[Claims] 1. A half-split axle case 1 in which an axle case 11 projectingly supporting the axles 6L and 6R is attached to a center plate 10 and both side surfaces of the center plate 10.
Axle 6 is installed inside a half-split axle case 11R that is composed of 1L and 11R and is attached to one side surface of the center plate 10.
A differential gear device for differentially connecting L and 6R and a gear reduction device are arranged, and a hydraulic motor M having a motor shaft 24 connected to the gear reduction device on the other side surface of the center plate 10, and the hydraulic motor. A hydraulic pump P for supplying pressure oil to M is assembled, and an oil passage for communicating the inlet / outlet port of the hydraulic pump P and the inlet / outlet port of the hydraulic motor M to form a closed circuit is bored in the center plate 10. HST integrated axle drive device characterized by: 2. An HST-integrated type axle drive device, characterized in that a half axle case 11L on the other side surface of the center plate 10 according to claim 1 is attached so as to cover the hydraulic pump P and the hydraulic motor M. . 3. The hydraulic motor M is attached to the half axle case 11L on the other side surface of the center plate 10 according to claim 1.
H is characterized in that the hydraulic pump P is mounted so as to cover only it, and the hydraulic pump P is covered by the pump case 12.
ST integrated axle drive.