CN108700046B

CN108700046B - Eccentric device, in particular for a pump of an ABS system, and pump for an ABS system

Info

Publication number: CN108700046B
Application number: CN201780010613.5A
Authority: CN
Inventors: 加藤慎吾; 大泷良一
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2016-02-15
Filing date: 2017-01-11
Publication date: 2021-09-07
Anticipated expiration: 2037-01-11
Also published as: DE102016202276B3; CN108700046A; KR20180109933A; WO2017140294A1; JP7026626B2; JP2019507297A

Abstract

Radial piston pumps are used in vehicles, for example in ABS systems. In the known design, the pump has a drive shaft with an eccentric section on which a roller bearing is placed, which rotates with its entirety eccentrically about the axis of rotation of the shaft. The object of the invention is to provide an eccentric device with high reliability during operation and a corresponding pump. For this purpose, an eccentric device (1) is proposed, having: a housing; an eccentric shaft section (4) for eccentric rotation about a main axis of rotation H, wherein the eccentric shaft section (4) provides or carries an inner raceway (9); a rolling bearing arrangement (7), wherein the rolling bearing arrangement (7) is arranged on the eccentric shaft section (4) and defines an eccentric axis E, wherein the rolling bearing arrangement (7) has a plurality of rolling bodies (12) and an outer raceway arrangement (8), wherein the outer raceway arrangement (8) provides an outer raceway (10) for the rolling bodies (12), and wherein the rolling bodies (12) roll in a rolling body space (11) on the inner raceway (9) and on the outer raceway (10); the supporting element (17) and the supporting surface (18) serve as supporting partners, wherein the supporting element (17) rests on the supporting surface (18) in a moving manner, wherein the supporting partners jointly form an axial support of the eccentric shaft section (4) on the housing (5), and wherein one of the supporting partners is arranged fixedly relative to the housing and the other supporting partner is supported on the eccentric shaft section (4), wherein the supporting surface (16) is arranged fixedly relative to the housing.

Description

Eccentric device, in particular for a pump of an ABS system, and pump for an ABS system

Technical Field

The invention relates to an eccentric device, comprising: a housing; an eccentric shaft section for eccentric rotation about a main axis of rotation, wherein the eccentric shaft section provides or carries an inner raceway; a rolling bearing arrangement, wherein the rolling bearing arrangement is arranged on the eccentric shaft section and defines an eccentric axis, wherein the rolling bearing arrangement has a plurality of rolling bodies and an outer raceway arrangement, wherein the outer raceway arrangement provides an outer raceway for the rolling bodies, and wherein the rolling bodies roll in a rolling body space on the inner raceway and on the outer raceway; the support element and the support surface serve as support partners, wherein the support element rests on the support surface in a moving manner, wherein the support partners jointly form an axial support of the eccentric shaft section on the housing, and wherein one of the support partners is arranged fixedly with respect to the housing, while the other support partner rests on the eccentric shaft section. The invention also relates to a pump for an ABS system, having such an eccentric device.

Background

Such pumps are used in vehicles, for example in ABS systems and are based on the radial plunger principle. The pump has, in a known manner, a drive shaft with an eccentric section on which a rolling bearing is placed, which rotates with its entirety eccentrically about the axis of rotation of the shaft. The pump has a piston-cylinder device for pumping a fluid, wherein the piston ends rest on the outer circumferential surface of the rolling bearing and are actuated in an oscillating manner by the circumferential surface of the rolling bearing and thus by the eccentric movement of the rolling bearing.

Such a pump is disclosed in document DE 10241306 a1, which is the closest prior art. On the eccentric section of the shaft, a rolling bearing is placed, which is formed by a needle sleeve in which a plurality of needles are arranged in a cage. The needle sleeve is closed at one axial end and forms with this axial end a contact surface for a ball which is arranged securely in the housing of the pump so that the needle sleeve can be supported on the ball during the eccentric movement. On the opposite axial end, the needle sleeve ends in an edge, which is arranged circumferentially as a through-opening for the eccentric section. In the radial direction, the piston end of the working piston is supported on the needle roller sleeve.

Disclosure of Invention

The object of the invention is to provide an eccentric device with high reliability during operation and a corresponding pump.

The subject of the invention is an eccentric device which is preferably suitable for a pump and/or for a pump configuration. The pump is preferably adapted and/or configured for generating hydraulic pressure in an ABS system of a vehicle.

The eccentric device has an eccentric shaft section, wherein the eccentric shaft section is structurally configured such that it rotates eccentrically about a main axis of rotation. Preferably, the eccentric shaft section is arranged eccentrically on the drive shaft, wherein the drive shaft defines a main axis of rotation by rotation thereof. Optionally, the drive shaft forms part of an eccentric device. The eccentric shaft section provides an inner raceway or carries a member with an inner raceway. Particularly preferably, the inner race is arranged on or formed by the base material of the eccentric shaft section.

The eccentric device has a rolling bearing arrangement, wherein the rolling bearing arrangement is in particular designed as a radial rolling bearing arrangement. The rolling bearing arrangement is arranged on the eccentric shaft section and defines an eccentric axis with its axis of rotation. The eccentric axis and the main axis of rotation are arranged offset in parallel to one another, wherein the eccentric axis rotates eccentrically about the main axis of rotation during operation.

The rolling bearing arrangement has a plurality of rolling bodies and an outer race arrangement, wherein the rolling bodies are arranged in the outer race arrangement around an eccentric axis in a rolling body chamber. The rolling bodies are in particular designed as rollers, in particular as needles. In the embodiment designed as a needle roller, the needle roller has an axial longitudinal extent which is greater than three times the diameter. The rolling bodies, in particular the rollers, are preferably arranged in the cage and are particularly preferably guided by the cage. The outer raceway arrangement provides an outer raceway for the rolling elements. The outer race arrangement is preferably designed rotationally symmetrically with respect to the eccentric axis. The rolling bodies roll, in particular roll, on the inner raceway and on the outer raceway. The inner and/or outer raceways are preferably designed as straight cylindrical circumferential surfaces which are arranged coaxially and/or concentrically with respect to the eccentric axis.

The eccentric device has a support element and a support surface, wherein the support element and the support surface each form a support counterpart. The support element rests in a moving manner on the support surface.

In this case, it can be provided that the eccentric device is designed such that the supporting element, as a sliding element, during operation moves only slidingly on the supporting surface as a sliding surface, or the supporting element, as a sliding rolling element, rolls on the supporting surface as a sliding rolling surface and simultaneously slides. Furthermore, it can be provided that the support element is designed as a rolling element which only rolls on a support surface as a rolling surface.

The support surface is preferably flat, in particular planar. The support partners together form an axial support of the eccentric shaft section on the housing. In particular, the support partner forms a transmission link or a transmission chain for transmitting pressure forces between the eccentric shaft section and the housing, more precisely in an axial direction relative to the main axis of rotation and/or the eccentric axis. Stipulating: one of the support partners is supported on the eccentric shaft section for transmitting axial pressure while the other support partner is arranged fixedly relative to the housing.

Within the scope of the invention, it is claimed that the support surface is arranged as a support partner in a fixed manner relative to the housing. This embodiment makes it possible for the load introduced by the supporting element into the supporting surface to be dissipated via the housing and in this way to protect the moving parts of the eccentric device from the load. If this embodiment is compared with the known prior art, it is certain that the following risks exist in the widely known structural forms: the bearing surfaces pivot in a plane perpendicular to the main axis of rotation and/or the eccentric axis due to the pressure load caused by the support elements and in this way introduce stresses into the rolling bearing. In contrast, the support surface is accommodated in a fixed manner relative to the housing and can thus be supported more stably. As a result, the load acting on the rolling bearing is reduced, the wear of the rolling bearing is reduced and the reliability of the eccentric device in operation is therefore improved.

It is particularly preferred that the support element is supported in the radial direction by the outer race arrangement. The radial direction is particularly with reference to the eccentric axis. In particular, an interaction is formed between the support element and the outer race arrangement. On the one hand, the support element is held on the eccentric axis by the outer raceway arrangement so that tilting or shifting is minimized, and on the other hand, the outer raceway arrangement is held in a predetermined position by the support element and/or is held in the correct position.

In a preferred development of the invention, the outer race arrangement is held in the axial direction of the eccentric axis, more precisely in relation to the bearing surface, by the bearing element, preferably in a form-fitting manner (formschlussig). Furthermore, it is thus ensured by the support element that: the outer race means cannot move towards the support surface but is secured in position correctly. The axial positioning or guiding of the outer race arrangement by means of the supporting element therefore likewise increases the service life of the rolling bearing arrangement and thus the reliability of the eccentric device.

Particularly preferably, the support element is designed as a sphere. In this embodiment, it is also particularly preferred that the support surface is of planar or planar design.

The balls can be accommodated in the outer raceway arrangement in a rotationally fixed manner. Alternatively, the ball is mounted so as to be rotatable and/or rollable, so that the ball can be rotated in the outer race arrangement with low friction as a support element rolls on the support surface.

The stop surface, in particular the front surface on the eccentric shaft section on which the ball is supported as a support element, can be of flat design. Alternatively, the surface carries a centering, as for example a deepened portion, in order to define the ball as a support element in this position.

In principle, it can be provided that the support surface is formed by the base material of the housing and is therefore only formed as a preferably planar region of the housing. In a preferred refinement of the invention, the eccentric device has a support plate, wherein the support plate is arranged immovably in the housing or immovably relative to the housing and forms the support surface. This design has following advantage: the housing can be produced from a cost-effective material, such as an aluminum alloy, and nevertheless sufficient wear resistance and mechanical stability can be achieved by the inserted support plates, which are produced, for example, from steel. The support plate may be configured as a plate-shaped member. Alternatively, the support plate is a section of a more complex component arranged fixedly with respect to the housing.

In a preferred embodiment of the invention, the outer race arrangement has a receptacle for the support element. Particularly preferably, the support element can be arranged in a loss-proof manner in the receptacle and/or in the receptacle. Such a receptacle makes the eccentric device easy to assemble, since the support element, in particular the ball, is not inadvertently lost during assembly.

In a particularly preferred embodiment, the receptacle is designed as a snap receptacle into which the support element, in particular a ball, can be snapped. In the snap-in receptacle, the support element, in particular a ball, is held in a form-fitting and/or force-fitting manner.

It is optionally possible for the receptacle to be designed as a bearing, in particular as a sliding bearing and/or a rolling-body bearing, in particular as a ball bearing, for the support element, in particular a ball.

In a very cost-effective production, the outer race device is designed as a sleeve with a sleeve base. The sleeve is particularly preferably produced by deformation technology and is in particular designed as a deep-drawn sleeve. It can be provided that the receptacles, in particular the snap receptacles, are introduced into the sleeve bottom sequentially by a process of deformation and detachment. Particularly preferably, the sleeve base has a through-hole, in particular circular, which has the following diameter in the direction of the eccentric shaft section: the diameter is selected to be smaller than the diameter of the support element, in particular the diameter of the ball, and furthermore has a concave receiving structure which receives the support element, in particular the ball, in a form-fitting manner.

Another subject matter of the invention is a pump for an ABS system, wherein the pump has an eccentric device provided according to the solution of the invention, wherein the eccentric shaft section is in operative connection with a drive shaft of the pump, in particular is coupled in a rotationally fixed manner, and the pump has at least one piston-cylinder unit, wherein the piston ends of the pistons are supported on the outer circumferential surface of a rolling bearing device, so that a rotary motion of the input shaft is converted into an oscillating motion of the pistons via the eccentric shaft section and the rolling bearing device.

Drawings

Further features, advantages and effects of the invention will be obtained from the following description of a preferred embodiment of the invention and from the accompanying drawings. Wherein:

fig. 1 shows a schematic longitudinal section of a pump with an eccentric device as a first embodiment of the invention;

fig. 2 and 3 each show a schematic longitudinal section in a partially enlarged view of a receptacle as an outer race arrangement.

Detailed Description

Fig. 1 shows an eccentric device 1 as a detail of a pump 22 for an ABS system in a schematic longitudinal sectional view. The pump 1 is configured as a radial piston pump and converts a rotary motion introduced via the input shaft 2 into an oscillating motion of two piston rods or pistons 3 in this example. The oscillating movement extends in a radial direction with respect to a main axis of rotation H defined by the rotation of the input shaft 2.

The eccentric shaft portion 4 is arranged on the input shaft 2 and is connected in particular in a rotationally fixed manner to the input shaft 2 or forms an end portion of the input shaft 2. The eccentric shaft section 4 is of circular design in a cross section perpendicular to the main axis of rotation H. The eccentric shaft section 4 defines an eccentric axis E, wherein the eccentric axis E is arranged offset in parallel with respect to the main axis of rotation H of the input shaft 2. The input shaft 2 is rotatably mounted in a housing 5 of the pump 1 via a bearing arrangement 6, which is designed as a ball bearing. A rolling bearing device 7 is arranged on the eccentric shaft section 4.

The rolling bearing arrangement 7 has an outer raceway arrangement 8, which is designed as a sleeve. The eccentric shaft section 4 provides an inner raceway 9 and the outer raceway arrangement 8 provides an outer raceway 10. The inner raceway 9 and the outer raceway 10 are coaxially and concentrically formed with respect to one another and are each embodied as a straight cylindrical circumferential surface. The inner and outer raceways 9, 10 are also oriented coaxially and/or concentrically with respect to the eccentric axis E. In the outer race arrangement 8, a plurality of rolling bodies 12 are arranged in a rolling body space 11, which rolling bodies are designed as rollers, in particular cylindrical rollers, and which roll, in particular roll, on the inner race 9 and the outer race 10. The plunger 3 rests with its free end against the outer circumferential surface 13 of the outer raceway arrangement 8.

The outer race device 8, which is designed as a sleeve, has a sleeve bottom 14 which closes the outer race device 8 on one axial side. Between the end side 15 of the eccentric shaft section 4 and a support plate 16, which is arranged in the housing 5, a support element 17 in the form of a sphere is arranged, wherein the eccentric shaft section 4 is supported with its end side 15 on the support plate 16 via a sphere. More precisely, the ball forms a support element 17 which is supported on a support surface 18 of a support plate 16 as a further support counterpart. The support surface 18 and the end faces are oriented parallel to one another. The sleeve bottom 14 has a through-hole 19 in which the ball is arranged. The ball and/or the through hole 19 is arranged centrally with respect to the eccentric axis E. In the radial direction, the supporting element 17 (which is designed as a ball) is supported on the outer race arrangement 8, so that the outer race arrangement 8 and the supporting element 17 (which is designed as a ball) are centered relative to one another with respect to the eccentric axis E. For example, the housing 5 is constructed from an aluminum alloy and the support plate 16 is realized from a steel material, so that the support is constructed with low or even no wear.

Fig. 2 and 3 show a section of the sleeve bottom 14 in the region of the through-opening 19, one with the support element 17 (fig. 2) and one without the support element 17 (fig. 3). It can be seen that the through-hole 19 forms a receptacle 20 for the support element 17 in the form of a sphere. As can be gathered in particular from fig. 3, the through-opening 19 tapers on the side facing the eccentric shaft section 4 to a diameter D1, wherein the diameter D1 is smaller than the diameter D0 of the ball. In the central region, the receptacle 20 has a diameter D2 or a diameter profile matching the diameter D0 of the ball, so that the ball is held in a snap-fit manner. In other words, the ball can snap into the receptacle 20 and be held there in a loss-proof manner. The diameter D1 is embodied here such that the ball cannot be pushed through the sleeve bottom 14, or the sleeve bottom 14 can be pulled over the ball in the direction of the arrow 21 toward the support surface 18. The sleeve bottom 14 and thus the outer race arrangement 8 are thereby blocked against displacement in the direction of the support plate 16 by means of a ball-and-socket joint.

The receptacle 20 can be formed, for example, rotationally symmetrically in an axial plan view or by a plurality of tongues which run in the radial direction.

List of reference numerals

1 eccentric device

2 input shaft

3 plunger piston

4 eccentric shaft section

5 casing

6 bearing device

7 rolling bearing device

8 outer raceway device

9 inner raceway

10 outer raceway

11 rolling body space

12 rolling element

13 peripheral surface

14 bottom of sleeve

15 end side

16 support plate

17 support element

18 bearing surface

19 through hole

20 accommodating part

21 arrow head

D0, D1, D2 diameters

E eccentric axis

H main axis of rotation

Claims

1. An eccentric device (1) is provided,

is provided with a shell body which is provided with a shell body,

having an eccentric shaft section (4) for eccentric rotation about a main axis of rotation (H), wherein the eccentric shaft section (4) provides or carries an inner raceway (9),

having a rolling bearing arrangement (7), wherein the rolling bearing arrangement (7) is arranged on the eccentric shaft section (4) and defines an eccentric axis (E),

wherein the rolling bearing arrangement (7) has a plurality of rolling bodies (12) and an outer raceway arrangement (8), wherein the outer raceway arrangement (8) provides an outer raceway (10) for the rolling bodies (12), and wherein the rolling bodies (12) roll in a rolling body space (11) on the inner raceway (9) and on the outer raceway (10),

having a supporting element (17) and having a supporting surface (18) as a supporting counterpart, wherein the supporting element (17) rests on the supporting surface (18) in a moving manner, wherein the supporting counterparts jointly form an axial support of the eccentric shaft section (4) on the housing (5), and wherein one of the supporting counterparts is arranged fixedly with respect to the housing and the other supporting counterpart is supported on the eccentric shaft section (4),

it is characterized in that the preparation method is characterized in that,

the support surface (18) is arranged fixedly relative to the housing.

2. Eccentric device (1) according to claim 1, characterized in that the support element (17) is supported in the radial direction by the outer raceway arrangement (8).

3. Eccentric device (1) according to one of the preceding claims, characterized in that the outer raceway arrangement (8) is held in the axial direction relative to the support surface (18) by the support element (17).

4. Eccentric device (1) according to claim 1 or 2, characterized in that the supporting element (17) is configured as a sphere.

5. Eccentric device (1) according to claim 1 or 2, characterized in that the eccentric device (1) has a support plate (16), wherein the support plate (16) is fixedly arranged in the housing (5) or in relation to the housing and forms the support surface (18).

6. Eccentric device (1) according to claim 1 or 2, characterized in that the outer raceway arrangement (8) has a receptacle (20) for the support element (17).

7. Eccentric device (1) according to claim 6, characterized in that the housing (20) is configured as a snap-in housing.

8. Eccentric device (1) according to claim 1 or 2, characterized in that the outer raceway arrangement (8) is configured as a sleeve.

9. Eccentric device (1) according to claim 6, characterized in that the housing (20) is formed into an outer raceway arrangement (8) configured as a sleeve.

10. Pump (22) for an ABS system, characterized by an eccentric device (1) according to one of the preceding claims.