JPH03153951A - Hst axle driving device - Google Patents

Abstract

PURPOSE:To eliminate aligning process for shafts and facilitate assembly by arranging the axes of an output shaft, gear shaft, and car axles in the same plane, providing possibility of dividing a housing into two pieces about this plane, and installing the shafts to either piece of the housing sections. CONSTITUTION:Axes of the output shaft 18 of a hydraulic motor 4 and the gear shaft 7e of a gear train 7 coupled therewith are arranged in the same plane 10 as the axes of the left and right car axles 5l, 5r to be driven by the mentioned gear train 7 through a differential gear 6. The housing is divided about the plane 10 into pieces 1r, 1f, and the mentioned shafts are arranged at and borne by either piece 1r of this divided housing, which ensures accommodation without unstableness of each shaft on its one side. Then the other housing piece 1f is put over it. This permits easy assembly without requiring alignment of the shafts with one another.

Description

[Detailed description of the invention] <Industrial application field> The invention includes a hydraulic pump and a gear train within the housing.

H that houses the hydraulic motor and differential gear
ST (hydro static transmission)
It relates to an axle drive device.

<Prior art> Conventionally, as this type of HST axle drive device, for example, the fourth
The one shown in the figure is known (Japanese Unexamined Patent Publication No. 64-45
No. 17). This axle drive device has left and right housings 41 (!, 41r) divided into two by a plane perpendicular to the axle.
A variable displacement hydraulic pump 43 and a constant displacement hydraulic motor 44 driven by pressure oil from the hydraulic pump are housed in the left housing 41Q, and are connected by a differential gear 46. Left and right axles 45g
45r is supported by the left and right housings 41 (!, 41r), and a gear train 47 that transmits the rotation of the hydraulic motor 34 to the pinion sleeve 50 of the differential gear 46 is housed in the right housing 41r.

The hydraulic pump 43 and the hydraulic motor 4.1 are connected through oil passages 48a48b provided in the wall of the left housing 4112, respectively. Then, the swash plate rotation shaft 5 of the hydraulic pump 43
4 to adjust the inclination of the swash plate (not shown) so that both axles 4
The rotation speed of the left and right axles 4512.4 when the vehicle turns is increased or decreased by the differential gear 46.
The rotational speed of the 5R is varied to enable smooth turning.

<Problems to be Solved by the Invention> However, in the above conventional axle drive device, the axle 4512.
The output shaft 52 of the hydraulic motor 44, each gear shaft of the gear train 47, and the left and right axles 4 are attached to either the left or right housing 4112 or 41r, which is divided into two by a plane perpendicular to 45r.
512, 45r are supported with their respective axes aligned, and both housings 4112.4'lr are integrally connected from both sides with their axes aligned, so assembly is very time-consuming and complicated. It has the disadvantage of becoming

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an ST axle drive device that can be assembled easily and quickly.

Means for Solving the Problems> In order to achieve the above object, the H9T axle drive device of the present invention includes a hydraulic pump 3. Hydraulic motor 4. Gear train 7 Differential gear 6, pair of axles 5L5r + In the housed HST axle drive, the shaft center of the output shaft 18 of the hydraulic motor 4 and the gear train connected to this output shaft [8] 7 and the pair of axles 50, 5 driven by the gear train 7 via the differential gear 6.
r and the axis thereof are disposed within the same plane 10 and supported by the housing, and the housing is separably joined at the plane lO.
It is characterized by being composed of r.

<Function> 1 (The housing 1f, Ir of the ST axle drive device is divided into two by a plane including the output shaft 18 of the hydraulic motor 4, the gear shaft 7e of the gear train 7, and the axle 5(i, 5r). During assembly, one side of each of the shafts 18.7e, 5f!, and 5r can be accommodated in one of the housings over substantially the entire length without wobbling. By simply stacking one housing on the other, the assembly can be performed easily and quickly without the need for time-consuming and meticulous alignment.

<Example> Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments.

1 and 2 are a front view and a side sectional view showing an example of an HST axle drive device, and this axle drive device is connected to the axial center of the output shaft 18 of the hydraulic motor 4 and to this output shaft 18. The axis of the gear shaft 7e of the gear train 7 to be driven by the gear train 7 and the axes of the left and right axles 512, 5r driven by the gear train 7 via the differential gear 6 are arranged in the same plane IO. The front and rear housings If and lr are separably joined at the plane IO, and the above-mentioned shafts are supported by both housings 1r and 1r. And both the housings lr.

In lr, hydraulic pump 3. Hydraulic motor 4. Gear train 7° differential gear 6 and left and right axles 5g.

Accommodates the base of 5r.

The front and rear housings If and Ir are divided into a right ventricle 25 and a left ventricle 26 by partition walls 24r and 24r that are symmetrically divided in half, and the upper part of the right ventricle 25 also serves as a valve vent. It accommodates an L-shaped manifold 2 (see Figure 3) and fixes it to the front housing l' with four bolts 23.The back surface 2a of the manifold 2
As shown in FIG. 3, cylinder blocks 12 and 15 are rotatably and liquid-tightly attached to the left end face 2b, respectively, and the hydraulic pump 3 and the hydraulic motor 4 are accommodated in a manner perpendicular to each other.

As shown in FIGS. 2 and 3, the hydraulic pump 3 is supported by a bearing 3 with its tip protruding from the rear housing Ir, and has a drive shaft 11 that rotationally drives a cylinder block 12.
and a piston 13,1 fitted in the cylinder block 12.
3. It consists of a movable swash plate 14 that regulates the reciprocating motion of... and increases/decreases the discharge amount.

As shown in FIGS. 1 and 3, the hydraulic motor 4 is fixed to the inner end surface of a support sleeve 28 that fits into holes in the partition walls 24f and 24r, and is controlled by the reciprocating motion of the pistons 16, 16, . The output shaft 18 includes a fixed swash plate 17 that regulates the rotation of the cylinder block 15 and converts it into rotation of the cylinder block 15, and an output shaft 18 that is spline-coupled to the cylinder block 15 and supported by the support sleeve 28 via a bearing 29. As shown in FIG. 3, the manifold 2, which forms the valve plate for the hydraulic pump 3 and the hydraulic motor 4, has a discharge passage 8 that communicates the discharge boat of the pump 3 with the inflow boat of the motor 4, and a suction port of the pump 3. A suction passage 9 is provided which communicates with the discharge port of the motor 4.

On the other hand, the left chamber 26 separated by the partition walls 24r and 24f accommodates the gear train 7 and the differential gear 6 that transmit the rotation of the output shaft 18 of the hydraulic motor 4 to the pinion shaft 20 of the differential gear 6. , supports a left axle 5Q whose base end is connected to the differential gear 6. The right axle 5r, whose base end is connected to the differential gear 6, is supported in the lower part of the right chamber 25. As shown in FIG.
b.

The signal is transmitted to the gear 7d via the gear 7c, causing the pinion shaft 20, whose both ends are supported by a differential case 19 coaxially fixed to the gear 7d, to rotate. and the left and right axles 5, respectively, through the side gears 22L22r that mesh with the left and right axles 5.
The signal is transmitted to f2 and 5r.

The operation of the H8T axle drive system having the above configuration will be described next.

The housing of the HST axle drive is connected to the output shaft 18. of the hydraulic motor 4, as shown in FIG. 1.2. Plane 1 including gear shaft 7e of gear train 7 and left and right axles 5Q, 5r
Since the rear housing 1f and lr are divided into two parts at the point 0, when assembling the device, for example, as shown in FIG.
One side of the outer circumferential surface of 5C and 5r is attached to a support sleeve 28. which is assembled to these shafts. Hydraulic motor 4. Hydraulic pump 3.
Gear train 7. Differentiarynyarugya6. It can be supported and accommodated with bearings etc. without wobbling. Therefore,
After supporting and accommodating each shaft in this way, in the housing 1r,
Overlap the front housing If, and both housings 1f and I
bolt holes 39, 39. r scattered around its outer edge. ...(
By simply inserting bolts into the shafts (see Fig. 1) and connecting them, assembly can be easily and quickly performed without the need for time-consuming alignment of each shaft. Conversely, even if the above-mentioned axles 1B, 7e, 5L5r are supported and accommodated in the front housing r and the rear housing lr is superimposed thereon, the HST axle drive device can be assembled easily and quickly in the same way as described above. can.

In other words, in the conventional example shown in Fig. 4, in which the housing is divided into two parts 419.41r on a vertical plane perpendicular to the axles 45l and 45r, the left and right axles are housed in one of the housings in a shaky state. 45ri.

45r, the output shaft 52 of the hydraulic motor 44, the gear shaft of the gear train, etc., it was necessary to overlap the housings from both sides while aligning them with each other, but with the present invention, there is no need for alignment and assembly is very easy. It becomes easier.

The operation of the axle drive device is no different from that of the conventional example described in FIG. That is, when the movable swash plate 14 is adjusted to a predetermined inclination and the cylinder block 12 of the hydraulic pump 3 is rotated by the engine via the drive shaft l, a predetermined amount of water is discharged by the forward movement of the piston 13 accompanying the rotation. Pressure oil is
Pressure oil accompanying the backward movement of the piston 16 of the hydraulic motor 4 is supplied to the piston 16 of the hydraulic motor 4 through the discharge passage 8 of the manifold 2 to cause it to move forward, while the pressure oil accompanying the backward movement of the piston 16 of the hydraulic motor 4 is supplied to the hydraulic pump The cylinder block 15 of the hydraulic motor 4 is rotated by being sucked in by the reciprocating piston 13 of No. 3. cylinder block 15
The rotation of the output shaft I8 is transmitted to the differential gear 6 via the gear train 7a to 7d, causing the pinion shaft 20 to rotate, and this rotation causes the left, The right axle 5L5r is rotated at a predetermined speed.

In the above embodiment, the hydraulic pump 3 and the hydraulic motor 4 in the first chamber 25 are connected to the oil passage 38a provided in the housing wall of the conventional example.
38b (see FIG. 4), the discharge and suction passages 8.9 of the manifold 2 which also serves as a valve plate fixed in the first chamber 25
, there is no need to provide complex-shaped oil passages 38a and 38b in the wall of the housing lrJ&, and there is an advantage that the housing can be easily made by die-casting without requiring much time and effort in making molds. be.

It goes without saying that the present invention is not limited to the illustrated embodiment.

<Effects of the Invention> As is clear from the above description, the HST axle drive device of the present invention arranges the output shaft of the hydraulic motor, the gear shaft of the gear train, and the axle in the same plane. Since the two housings are separably joined at a flat surface and both housings support each of the above shafts, either of the housings can support and house each of the above shafts together with the members assembled thereon without wobbling. However, by simply superimposing the other housing on top of this, the device can be assembled easily and quickly without the need for time-consuming alignment of each axis.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the HST axle drive device of the present invention, FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1, and FIG. 3 is a sectional view taken along the line [-111] in FIG. , FIG. 4 is a longitudinal sectional view of a conventional axle drive device. l r...Front, rear housing, 3...Hydraulic pump, 4...Hydraulic motor, 5 Q, 5 r...
Left and right axles, 6...Differential gear, 7...
・Gear train, 7e... Gear shaft, 18... Output shaft.

Claims (1)

[Claims] (1) Inside the housing, there is a hydraulic pump (3), a hydraulic motor (4), a gear train (7), and a differential gear (6).
, an HST axle drive system that accommodates a pair of axles (5l, 5r), the axial center of the output shaft (18) of the hydraulic motor (4) and the gear train (7) connected to this output shaft (18). ) and the axes of the pair of axles (5l, 5r) driven by the gear train (7) via the differential gear (6), on the same plane (10). An HST axle drive device, characterized in that the HST axle drive device is comprised of two parts (1f, 1r) disposed within the housing and supported by the housing, and the housing is separably joined at the plane (10).