阅读说明：本技术 偏心泵的偏心驱动装置 (Eccentric driving device of eccentric pump ) 是由 E·库尔茨 W·舒勒 于 2020-02-18 设计创作，主要内容包括：本发明涉及一种尤其车辆制动设备的偏心泵(10)的偏心驱动装置,其具有驱动轴(32)和位置固定地布置在该驱动轴上的偏心件(36),借助于该偏心件在驱动轴(32)旋转时可将至少一个泵元件(18、20)置于运动中。根据本发明,偏心件(36)在其背离驱动轴(32)的外侧(40)至少局部地球形地设计。(The invention relates to an eccentric drive of an eccentric pump (10), in particular of a vehicle brake system, having a drive shaft (32) and an eccentric (36) arranged in a stationary manner thereon, by means of which at least one pump element (18, 20) can be set in motion when the drive shaft (32) is rotated. According to the invention, the eccentric (36) is at least partially spherically designed on its outer side (40) facing away from the drive shaft (32).)

1. An eccentric drive of an eccentric pump (10), in particular of a vehicle brake system, having a drive shaft (32) and having an eccentric (36) arranged in a positionally fixed manner thereon, by means of which eccentric at least one pump element (18, 20) can be moved when the drive shaft (32) is rotated, characterized in that the eccentric (36) is at least partially spherical on its outer side (40) facing away from the drive shaft (32).

2. Eccentric drive (10) according to claim 1, characterized in that the eccentric (36) is completely spherical at its outer side (40) facing away from the drive shaft (32).

3. Eccentric drive device (10) according to claim 2, characterized in that the eccentric (36) is provided with a through hole (42) eccentric with respect to the spherical shape to accommodate the drive shaft.

4. Eccentric drive (10) according to claim 3, characterized in that the eccentric (36) is connected in a rotationally fixed manner to the drive shaft (32) at the through-opening (42), in particular is press-fitted onto the drive shaft (32).

5. Eccentric drive (10) according to one of claims 1 to 4, characterized in that the at least partially spherically designed eccentric (36) is surrounded by an eccentric cage (44) which is likewise at least partially spherical at its inner side (46) facing the eccentric (36).

6. Eccentric drive (10) according to claim 5, characterized in that the at least partially spherically designed eccentric (36) is surrounded by an eccentric housing (44) which is likewise at least partially spherical on its inner side (46) facing the eccentric (36).

7. Eccentric drive device (10) according to claim 6, characterized in that the eccentric housing (44) completely surrounds the eccentric (36).

8. Eccentric drive device (10) according to one of claims 1 to 7, characterized in that the eccentric housing (44) is designed arched at its outer side (40) facing away from the eccentric (36) and at its arched portion (50) with at least one flattened portion (52).

9. Eccentric drive (10) according to claim 8, characterized in that the eccentric housing (44) is ring-shaped and is provided at its outer side (40) facing away from the eccentric (36) with two diametrically opposed flattened sections (52).

10. Use of an eccentric drive (10) according to one of claims 1 to 9 on a vehicle brake system, in particular on an eccentric pump (10) of a vehicle brake system.

Technical Field

The invention relates to an eccentric drive of an eccentric pump, in particular of a vehicle brake system, having a drive shaft and an eccentric arranged in a stationary manner on the drive shaft, by means of which at least one pump element can be set in motion when the drive shaft is rotated. The invention also relates to the use of such an eccentric drive in a vehicle brake system.

Background

Eccentric drives of the type mentioned at the outset are used in piston pumps to reciprocate the piston. In the event of a movement of the piston, hydraulic medium can be pumped in the associated pressure chamber. Such piston pumps are used in particular in vehicle brake systems. At this time, the brake fluid as the hydraulic medium is pumped out of or toward the wheel brakes by the piston pump. The eccentric drive comprises a motor, an eccentric and an eccentric bearing surrounding the eccentric. For cost reasons, the known eccentric is supported as a needle bearing. However, such needle bearings have relatively large axial and radial clearances. Undesirable vibration excitations of the piston may occur.

Disclosure of Invention

The object of the invention is to provide an eccentric drive of an eccentric pump which has a high degree of flexibility with a relatively small axial and radial play when the relative piston position changes.

This object is achieved by means of an eccentric drive of an eccentric pump, in particular of a vehicle brake system, having a drive shaft and an eccentric which is arranged in a positionally fixed manner on the drive shaft and by means of which at least one pump element can be set in motion when the drive shaft is rotated. According to the invention, the eccentric is at least partially spherical on its outer side facing away from the drive shaft.

In other words, the core of the invention is the realization of an eccentric bearing that is particularly cost-effective, at the same time low in vibrations and still has positional tolerances, by means of a ball joint and a spherical cap. The piston of the associated eccentric pump can be supported rigidly in the radial direction at the spherical cap. At the same time, the ball enables a certain change in position of the supported piston in the circumferential direction without the radial distance of the contact surface of the piston at the ball being changed in this case. Thus, the piston can be moved slightly in the transverse direction of the piston at the ball-shaped element without the position of the piston being changed accordingly in the longitudinal direction of the piston. The piston is therefore excited to vibrate correspondingly less. At the same time, this solution can also be produced more cost-effectively than a solution with conventional needle bearings.

In this case, it is particularly preferred if the eccentric is completely spherical on its outer side facing away from the drive shaft. A particularly wide surface for position compensation is achieved by this spherical shape in the circumferential direction of the spherical part.

Furthermore, the eccentric according to the invention is preferably provided with a through hole eccentric with respect to the spherical shape to accommodate the drive shaft. The drive shaft can be inserted into the eccentric part through such a through-opening, so that a rotationally fixed connection between the drive shaft and the eccentric part is achieved. The eccentric element is preferably connected to the drive shaft in a rotationally fixed manner, in particular pressed onto the drive shaft, in each case at the through-opening.

The at least partially spherically designed eccentric is preferably surrounded by an eccentric housing, which is likewise at least partially spherically designed on its inner side facing the eccentric. The eccentric housing thus provides a sliding fit with the spherical eccentric, by means of which the eccentric housing can slide along the spherical eccentric. A slide bearing is thus provided, at which one or preferably several pistons of the associated piston pump can be supported on the outside. The at least partially spherically designed eccentric is therefore preferably surrounded by an eccentric cage, which is likewise at least partially spherical on its inner side facing the eccentric.

Furthermore, the eccentric housing preferably completely surrounds the eccentric. Such an eccentric housing offers the possibility of being able to support the piston over its entire circumference. Furthermore, such an eccentric housing encloses the eccentric, so that the eccentric housing cannot undesirably fall off the eccentric, in particular cannot move downward, during operation of the associated eccentric pump.

Furthermore, the eccentric housing is preferably arched on its outer side facing away from the eccentric and is designed with at least one flattened section on its arched section. The flattened section provides a surface, in particular a flat surface, against which an associated piston of the eccentric pump can abut, so that the housing does not significantly change its position in the circumferential direction under the action of the piston. The eccentric housing can be moved further in the circumferential direction, in particular because the flattened section is not acted upon by the piston. The flattened section causes the piston to always abut the center of the flattened section and not move to or beyond the edges of the flattened section.

The eccentric housing is preferably circular and has two diametrically opposite flattened portions on its outer side facing away from the eccentric. The two pistons can therefore be supported exactly opposite one another and advantageously on such an eccentric housing.

The invention also relates to the use of such an eccentric drive according to the invention in a vehicle brake system, in particular in an eccentric pump of a vehicle brake system.

Drawings

Embodiments of the solution according to the invention are further elucidated below with the aid of a schematic drawing. Wherein:

figure 1 shows a cross-section of a part of an eccentric pump with an eccentric drive according to the invention,

FIG. 2 shows a longitudinal section of a part of the eccentric pump according to FIG. 1, and

fig. 3 shows a perspective view of an eccentric of the eccentric drive according to fig. 1 and 2.

Detailed Description

Fig. 1 to 3 show an eccentric pump 10, for which a first piston pump 14 and a second piston pump 16 are arranged in a pump housing 12. The first piston pump 14 has a first pump element 18 in the form of a pump piston, and the second piston pump 16 has a second pump element 20 in the form of a structurally identical pump piston. The pump piston is moved back and forth along the first piston axis 22 and the second piston axis 24 by a predetermined distance in each case in order in this way to build up a pressure in the hydraulic medium present there in the respective first pressure chamber 26 and second pressure chamber 28. In the present case, the medium is brake fluid, and the eccentric pump 10 is provided to suck in brake fluid and to deliver it to a vehicle brake, not shown here, of a vehicle brake system.

The eccentric pump 10 is driven by means of a pump motor 30, which is mounted externally on the pump housing 12. The pump motor 30 projects with a drive shaft 32 into the pump housing 12 between the two piston pumps 14 and 16. Here, the drive shaft 32 rotates about a shaft axis 34. The eccentric 36 is mounted on the drive shaft 32 in a rotationally fixed manner, the eccentric axis 38 of the eccentric being offset from the shaft axis 34.

The eccentric 36 has an outer side 40 which is spherical with respect to the eccentric axis 38. In order to fix the eccentric 36 on the drive shaft 32, the eccentric is provided with a through-opening 42 which is eccentric with respect to the spherical shape and into which the drive shaft 32 is pressed.

An eccentric sleeve 44 is formed over the entire circumference of such an eccentric 36, the inner side 46 of which is likewise of spherical design and rests on the spherical outer side 40 of the eccentric 36 with a sliding fit or as a sliding bearing. The eccentric cam cage 44 surrounds the eccentric cam 36 in this case, so that it can slide along the eccentric cam with little play, i.e. without play.

The eccentric housing 44 has a cylindrical outer side 48 with an associated arcuate portion 50 relative to the eccentric axis 38. At the arched portion 50, two flattened portions 52 are formed on the outside 48 with respect to the eccentric axis 38, which are oriented tangentially or transversely to the radial direction. The two flattened portions 52 are disposed directly opposite each other relative to the eccentric axis 38. An end face end of one of the two pump elements 18, 20 is in contact with each of the two flattened areas 52.

When the drive shaft 32 is rotated by means of the pump motor 30, the eccentric 36 is set in an eccentric rotational movement due to the eccentric offset of the eccentric axis 38 relative to the shaft axis 34. At the same time, the eccentric cage 44 slides on the spherical outer side of the eccentric 36, wherein the eccentric 36 rotates in the interior of the eccentric cage 44. The two pump elements 18, 20 abutting the flattened section 52 prevent the eccentric housing 44 from rotating with the eccentric 36 and are simultaneously set by the eccentric to a reciprocating movement along the piston axes 22, 24 of the pump elements as a result of the eccentric rotation.