DE102004028044B3 - Bearing arrangement for axial piston pump, comprising toothed outer surface engaging with pinion - Google Patents

Abstract

The arrangement (1) is assembled of four bearing rings (2, 6, 8, 11), each providing a path for the ball elements (4, 7, 9, 12) and rotating around a central axis (3). The third and the fourth bearing ring (8, 11) are arranged in order to form an acute angle with the central axis (3). The second and the third ring (6, 8) are made of a single piece in a wedge shape (13) and provided with outer teeth (14) engaging with complementary teeth located at a pinion.

Description

The The invention relates to a bearing assembly for converting a rotational movement in a translational movement, in particular for an axial piston pump, consisting from a first bearing ring, which is arranged rotatably about a rotation axis is and has a first raceway for rolling elements, a second Bearing ring having a second raceway for the rolling elements, a third Bearing ring with a third raceway for rolling elements, which under a tilt angle is arranged to the rotation axis, a fourth bearing ring, the one fourth career for the Has rolling elements and which is arranged parallel to the third bearing ring, wherein rolling elements, in particular Balls, between first and second campings and between third and fourth bearing ring are arranged, wherein the second bearing ring and the third bearing ring are formed from a single component, wherein at least one of the resulting bearings as angular contact ball bearings is formed and wherein the component at its outer periphery with a toothing is provided.

Bearing arrangements are known in the art. It will be on the DE 90 13 630 U1 , on the DE 102 37 557 A1 and on the DE 198 34 754 A1 pointed. They are used in axial piston pumps, which are needed, for example, for high-pressure cleaners. Such a bearing arrangement is for example from the DE 197 38 813 A1 known. In the case of the axial piston machine disclosed therein, the bearing arrangement mentioned at the beginning is used. The drive of the bearing assembly is not disclosed in detail, but consists in axial piston pumps usually from a planetary gear, which is integrated into the axial piston machines. Thus, although a compact design of the pump is possible, but the drive is correspondingly expensive.

The DE 42 05 859 A1 discloses a similar solution for a swash bearing for use in an axial piston pump. Other solutions for driving a Axialkobenpumpe are from the DE 43 38 896 A1 , of the DE 36 31 408 A1 and the DE 198 34 754 A1 known.

all previously known solutions is common that partially meets the requirements for a stable axial and radial guidance the used bearing elements at the same time simple Drive the bearing assembly can not be accommodated. If purely axial leading Cylindrical roller bearings are used for their concept radial guiding property not very well. Although this can be achieved by the use of angular contact ball bearings be improved, but here is also usually a complicated solution when driving the pump. In this context is also the most high noise level during operation of the bearing assembly.

Of the The invention is therefore based on the invention, a bearing arrangement of the type mentioned so on, that said Disadvantages are avoided, d. H. with a simple drive option The bearing assembly should have a good radial and axial guiding property be given to the bearing assembly. In operation, the bearing assembly should characterized by a low noise. After all is still desired that the production of the bearing assembly in economically possible is.

The L ö s u n g this object by the invention is characterized that the toothing consists of plastic and to the component through an injection molding process is injected.

With This configuration results in the possibility of a particularly simple Drive the bearing assembly by a pinion engages the teeth and thus drives the bearing assembly. A planetary gear is for the Drive not required.

The Smooth running and the axial and radial guidance of the bearing assembly can Cheap be influenced if according to a first training is provided that the raceways of Lageringe at least two over Rolling elements more cooperative Bearing rings are introduced so that the contact angle to the axis of rotation between 30 ° and 45 °.

Prefers is provided that the forming the second and the third bearing ring Component is a sheet metal part.

The Component that forms the second and third bearing ring can continue in its radially outer region have a bent portion. This curved section is preferably formed hook-shaped at least on a part of the circumference.

Of the inventive proposal has the consequence that in a simple manner, ie using a simple manufacturing process, the bearing assembly can be produced, which is in operation by a relative quiet running and due to the simple drive mode excels.

In the drawing, an embodiment of the invention is shown. The single figure shows the radial section through a bearing assembly for on drove an axial piston pump.

The figure shows a bearing arrangement 1 , which is part of an axial piston pump. The bearing assembly has a total of four bearing rings, namely a first bearing ring 2 , a second bearing ring 6 , a third bearing ring 8th and a fourth bearing ring 11 , Every bearing ring 2 . 6 . 8th . 11 each has a career 4 . 7 . 9 respectively. 12 , the contact surfaces for rolling elements in the form of balls 5 and 10 form. The bearing assembly rotates about an axis of rotation 3 , the axis of rotation of the two bearing rings 2 and 6 equivalent. The third and fourth bearing ring 8th respectively. 11 are to the axis of rotation 3 arranged at a tilt angle α, which is typically in the range between 5 ° and 25 °.

When driving the bearing assembly 1 around the axis of rotation 3 This means that the fourth bearing ring 11 at a fixed circumferential point one in the direction of the axis of rotation 3 performs reciprocating axial movement, which serves for the drive of an axial piston, not shown, of the axial piston pump.

The second bearing ring 6 and the third bearing ring 8th are firmly connected, ie both bearing rings are made of a single component 13 produced. In the present case, both bearing rings exist 6 . 8th or the component 13 from a sheet metal part, which in the illustrated side view has a substantially wedge-shaped contour and in which the two raceways 7 and 9 are incorporated.

At the radially outer end, ie at the outer periphery, the component 13 with a toothing 14 Mistake. In this toothing, for example, designed as involute, an unillustrated pinion can engage to the component 13 drive. This then rotates both the second and the third bearing ring 6 . 8th , which results in the wobble, which is required for the drive of the axial piston. The gearing 14 can be carried out both as spur and as helical gearing.

In the exemplary embodiment, this is due to the components 2 . 5 and 6 formed first bearing designed as angular contact ball bearings, wherein the run guess the contact angle β (pressure angle) to the axis of rotation 3 between 30 ° and 45 °. That through the components 9 . 10 and 11 formed second bearing is designed as an axial ball bearing, but this does not necessarily have to be the case.

The component 13 that the two bearing rings 6 and 8th forms, is to attach the gearing 14 placed in a (not shown) injection molding tool, in which on the circumference of the component 13 Plastic melt is injected by a suitable mold so that the desired gearing 14 results. Thus the gearing 14 on the component 13 is firmly attached beyond the material adhesion, the component has 13 in its radially outer region a bent portion 15 extending over at least a certain peripheral area of the outer circumference of the component 13 extends around. The bent section 15 is - as it can be seen in the figure on the right - at least on a part of the circumference formed hook-shaped. The molded plastic compound thus has a positive connection to the component 13 ,

With the proposed embodiment of a bearing assembly can be a Very low-friction implementation of a rotary motion in a translatory Movement take place, as they are used to drive the axial piston of an axial piston pump is required. Both the radial and the axial guiding property the bearing arrangement is very good. Furthermore, there is a relative low noise Running when using the bearing assembly.

The proposed manufacturing process results in a stable bond between the component 13 and the gearing 14 , via which a simple and quiet drive the bearing assembly is possible.

1

bearing arrangement

2

first bearing ring

3

axis of rotation

4

first career

5

Rolling element (ball)

6

second bearing ring

7

second career

8th

third bearing ring

9

third career

10

Rolling element (ball)

11

fourth bearing ring

12

fourth career

13

component

14

gearing

15

curved section

α

tilt angle

β

contact angle

Claims (5)

Bearing arrangement ( 1 ) for converting a rotational movement into a translatory movement, consisting of a first bearing ring ( 2 ), which is about a rotation axis ( 3 ) is rotatably arranged and a first career ( 4 ) for rolling elements ( 5 ), a second bearing ring ( 6 ), who has a second career ( 7 ) for the rolling elements ( 5 ), a third bearing ring ( 8th ) with a third career ( 9 ) for rolling elements ( 10 ), which at a tilt angle (α) to the axis of rotation ( 3 ) is arranged a fourth bearing ring ( 11 ), who has a fourth career ( 12 ) for the rolling elements ( 10 ) and parallel to the third bearing ring ( 8th ) is arranged, wherein rolling elements ( 5 . 10 ) between first and second storage ( 2 . 6 ) and between the third and fourth bearing rings ( 8th . 11 ) are arranged, wherein the second bearing ring ( 6 ) and the third bearing ring ( 8th ) from a single component ( 13 ), at least one of the resulting bearings ( 2 . 5 . 6 ; 8th . 10 . 11 ) is designed as an angular contact ball bearing, wherein the component ( 13 ) at its outer periphery with a toothing ( 14 ) and wherein the toothing is made of plastic and to the component ( 13 ) is injection-molded by an injection molding process. Bearing assembly according to claim 1, characterized in that the raceways ( 4 . 7 . 9 . 12 ) at least two via rolling elements ( 5 . 10 ) cooperating bearing rings ( 2 . 6 ; 8th . 11 ) are introduced so that the contact angle (β) to the axis of rotation ( 3 ) is between 30 ° and 45 °. Bearing arrangement according to claim 1 or 2, characterized in that the second and the third bearing ring ( 6 . 8th ) forming component ( 13 ) is a sheet metal part. Bearing arrangement according to one of claims 1 to 3, characterized in that the component ( 13 ) in its radially outer region a bent portion ( 15 ) having. Bearing arrangement according to claim 4, characterized in that the bent portion ( 15 ) is hook-shaped at least on a part of the circumference.