DE2740821B2 - Bearing of the drive shaft of a bent axis axial piston machine - Google Patents

Description

The invention relates to the mounting of the drive shaft of a bent axis (swivel or inclined drum) Axial piston machine (pump or motor) for hydraulic fluids in a radial bearing arranged on the piston side and a drive side, their cone angle pointing in the same direction to the pistons and their fixed outer rings in a bearing housing are stored, wherein to compensate for the effective axial component of the piston forces acted upon by machine dragging fluid, on the outer ring of a the radial bearing acting counter-pressure pistons are provided.

It is known that the drive shaft of a bent-axis axial piston machine on the piston side via radial bearings that can be loaded obliquely, that is to say via tapered rollers or Support angular contact ball bearings that the force components emanating from the piston both in radial as also record in the axial direction. On the drive side, the drive shaft is mounted in a second roller bearing, which can be designed as a thrust bearing. In the so-called zero arrangement, the piston side and the drive side Radiax bearings used, which are supported by a spacer sleeve against each other in the way installed be that their cone angles point apart on the piston and on the drive (DE-OS 53 630).

However, the piston-side bearing is much stronger than the drive-side bearing from the piston forces loaded and is therefore subject to corresponding wear. To separate the piston-side bearing from the axial To relieve and on components of the piston forces to distribute two thrust bearings working in parallel according to a also known proposal (DE-OS 2112 822) the drive shaft between a piston-side and a drive-side radial bearing in one Tandem arrangement of two aligned bearings, one behind the other, stored for the transmission of the Axial forces on the bearing housing is the drive shaft each mk of the drive pulley and with a shoulder the shaft on the inner rings of the two, with Tandem thrust bearings with different diameters supported To distribute the axial forces on both bearings is the fixed outer ring of the drive-side thrust bearing over the outer ring of the radial bearing on the drive side supported on the housing,

is during the larger diameter Outer ring of the piston-side axial bearing rests on a counter-pressure piston acted upon by machine hydraulic fluid

This drive shaft bearing is of its construction

ago very expensive, because to support the bearing and counter-pressure piston gradations on the drive shaft and are provided in the housing inner wall, which because of the necessary fits a high Require manufacturing effort. It is also disadvantageous that the seals of the counter-pressure piston arranged between the bearings are difficult to access.

It is therefore dt; Object of the invention, a to create spatial arrangement for a drive shaft bearing of the type mentioned, with which the Manufacturing costs are reduced and the accessibility of the counter-pressure piston can be made easier.

This object is achieved with the means specified in the characterizing part of the main claim advantageous embodiment of the invention and a alternative embodiments are the subject of Subclaims.

In the invention, counter-pressure forces are used to compensate for the effective axial component of the piston forces on the stationary outer ring of the exerted on the drive-side bearing and via a spacer sleeve on the inner ring of the piston-side Transferred to the warehouse.

This arrangement results in a very useful, constructive structure for one with little Effort manufacturable drive shaft bearing, in which the drive shaft and the housing inner wall over the entire storage length are continuously cylindrical.

The pressure can be via an annular piston or - like

already known from DE-AS 19 39 084 - via single pistons arranged concentrically to the axis of rotation take place. In this previously known drive shaft bearing, however, the relief pistons slide on one rotating part of the drive shaft, whereby the Flow of low viscose media such as water or HSA fluids (95-97% water, 5-3% lubricant additive) and, at high pressures, in particular result in sealing difficulties that result in the volumetric efficiency of the axial piston machine ne worsen.

According to a further embodiment of the invention, the pressure can also be applied directly Effect of the machine pressure medium on the fixed outer ring of the drive-side bearing be applied. It is essential that the pressure is always exerted from an easily accessible point in the housing cover. In the following the invention is based on the in the

The drawing shows the exemplary embodiments illustrated

F i g. t and Fi g. 2 a transverse and a longitudinal section through the drive shaft bearings of a Schväg-axis axial piston machine with a drive-side Counter pressure piston,

Figure 3 is a longitudinal section of an alternative Extension of the drive shaft bearings,

F i g. 4 shows an excerpt from FIG. 3 in enlarged MaQsUb,

F i g. 5 and 6 show a cross section and a longitudinal section of another alternative embodiment of the drive shaft bearing.

The bent axis axial piston machine is at a use as a pump via a drive shaft 2 mounted in a bearing housing 1 by a drive not shown driven. The drive shaft 2 goes into a drive pulley 3, which is the bearing for a on a central pin 4 mounted pivoting or inclined drum 5 and the piston rod 6 forms the Pistons 7 in cylinder grooves 8 of drum 5 are led. Because of the drum inclination against the axis of rotation of the drive shaft 2 is the pressurized piston 7 with each revolution of the Drive shaft 2 moved up and down once.

The drive shaft 2 is mounted in the bearing housing 1 on the piston side and on the drive side in a radial bearing 9 and 10, which can optionally be designed as tapered roller bearings or as angular contact ball bearings. The cone angles β of the bearings 9 and 10 point in the same direction towards the pistons and their tips lie on the axis of rotation of the drive shaft 2. Both bearings 9 and 10 are supported against one another with their inner rings 11 rotating on the drive shaft 2 by a spacer sleeve 12. The outer rings 13 of the bearings 9 and 10 are fixedly mounted in the bearing housing 1. The bearing housing 1 is closed by a housing cover 14 towards the drive.

The reaction forces emanating from the obliquely guided pistons 7 load the radial axial bearing on the piston 9 with both an axially and a radially directed force component. To the piston side Radiaxlager 9 to partially relieve the axially directed component, is on the stationary Outer ring 13 of the radial bearing 10 on the drive side Counterforce exerted and over the inner ring 11 as well

Transfer the spacer sleeve 12 to the radial bearing 9 on the piston side.

This happens with the in Fi g. 1 and 2 illustrated embodiment through concentric to the axis of rotation of the drive shaft 2 in the drive-side housing cover

ίο 14 evenly distributed over the circumference, pressurizable counter-pressure piston IS, which is under the action of the counterforce on the stationary The outer ring 13 of the radial bearing 10 on the drive side is located. The pressure medium is supplied via a feed channel 16 supplied from the high pressure or pump side

In the embodiment of Figure 3 and 4 is between the outer ring 13 of the radial bearing 10 on the drive side and the housing cover 14 Annular channel 17 is provided, into which the "^ line channel 16 opens from the high pressure side, so that the counterforce generated by the pressure medium directly on the Outer ring 13 of the drive-side radial bearing 10 is exercised. The acted upon by the pressure medium The surface is delimited by sealing rings 18 in the housing cover 14. Further seals 19 are on the Inner wall of the bearing housing 1 is provided. This space-saving design of the counter-pressure device does not require any change in the structural dimensions of conventional bent-axis axial piston machines and can therefore be used with existing series without great effort.

In the embodiment according to FIG. 5 and 6, the counterforce is pressurized The annular piston 20 is applied in the housing cover 14 directly above the outer ring 13 of the drive-side Radialxlagers 10 is arranged The annular piston 20 is angular and lies with the flat Leg 21 on the outer ring 13 of the radial bearing 10 on the drive side and is connected to the steep leg 22 guided on the f ager housing 1 and sealed on both sides.

For this purpose 3 sheets of drawings

Claims (3)

Claims: 27 40 82t 1. Bearing of the drive shaft of a bent axis (swivel or inclined drum) axial piston machine (pump or motor) for hydraulic fluids in one radial bearing arranged on the piston side and one on the drive side, the cone angles of which point in the same direction to the pistons and their fixed outer rings are stored in a bearing housing, to compensate for the effective Axial component of the piston forces acted on by machine hydraulic fluid and acting on the outer ring of one of the radial bearing counter-pressure pistons are provided, characterized in that the counter-pressure pistons (15, 20) against the outer ring (13) of the radial bearing (10) on the drive side and that the inner ring (11) of the piston-side radial bearing (9) through a spacer sleeve pulled onto the drive shaft (2) (12) is supported on the Inuo ^ iring (11) of the drive-side radial bearing (10) 2. Storage of the drive shaft of a bent axis axial piston machine according to claim 1, characterized characterized in that the counter-pressure piston (15, 20) in a cover that closes the bearing housing (1) on the drive side towards the outside! (14) are arranged. 3. Storage of the drive shaft of a bent axis axial piston machine according to claim 1, characterized characterized in that for pressurizing the outer ring (13) of the radial bearing on the drive side (10) an annular channel (17) sealed on all sides is provided between this and the cover (14) of the bearing housing (1)