Master cylinder with guide sleeve for a sealing lip of the snifter system

Patent metadata

Field	Value
Publication number	US-10273981-B2
Application number	US-201515329085-A
Country	US
Kind code	B2
Filing date	Jul 24, 2015
Priority date	Aug 6, 2014
Publication date	Apr 30, 2019
Grant date	Apr 30, 2019

Abstract

The invention relates to a master cylinder for an actuating device of a clutch or a brake of a motor vehicle, including a cylinder housing having a pressure cylinder section, as well as a piston mounted movable relative to the cylinder housing, wherein the piston is arranged inside the pressure cylinder section in an actuation state in order to control a fluid pressure in a fluidically sealed pressure chamber by a sealing device on the piston side, and is arranged in a pressureless state such that the pressure cylinder section is fluidically connected to a retention system, wherein a seal of the sealing device is configured, and attached to the piston, such that it rests on a seal protection area of a stop element at least in a parking position in the pressureless state; as well as a method for mounting such a master cylinder.

First claim

The invention claimed is:

1. A master cylinder for an actuating device of a clutch or a brake of a motor vehicle, comprising a cylinder housing with a pressure cylinder section, a piston supported in a manner displaceable in reference to the cylinder housing, a sealing device connected to the piston, with the piston in an actuated state being arranged inside the pressure cylinder section in order to control a fluidic pressure in a pressure chamber sealed fluidically by the piston via the sealing device, and arranged in a pressureless state such that the pressure cylinder section is fluidically connected to a retention system, the sealing device having a seal that is embodied and fastened to the piston such that at least in a parking position, in the pressureless state, the seal contacts a seal protecting section of a stop element connected to the cylinder housing.

2. The master cylinder according to claim 1 , wherein the stop element is a part that is separate from the cylinder housing.

3. The master cylinder according to claim 1 , wherein the stop element is a cold formed part.

4. The master cylinder according to claim 1 , wherein the seal protecting section is formed at an interior circumferential side of the stop element, with an interior circumferential area that comprises, in proximity to the seal protection area, a first diameter remaining constant along the circumference.

5. The master cylinder according to claim 4 , wherein the first diameter of the seal protecting section is greater than a second diameter of the pressure cylinder section.

6. The master cylinder according to claim 5 , wherein the cylinder housing comprises a transitional section, in an axial direction conically expanding from the stop element away from the pressure cylinder section and comprises several radial grooves connected to the retention system.

7. The master cylinder section according to claim 1 , wherein the seal is annular with a sealing lip of the seal being embodied such that it contacts the seal protecting section as well as the pressure cylinder section.

8. The master cylinder according to claim 1 , wherein the stop element comprises a clamp-shaped holding section at a radial exterior side, which in an operating state is inserted in a receptacle of the cylinder housing in a radially fixed, but axially displaceable fashion.

9. The master cylinder according to claim 1 , wherein the stop element is pre-stressed by a disk spring in a direction of the pressure cylinder section.

10. A method for the assembly of the master cylinder according to claim 1 , comprising the following successively performed steps:
a) inserting the piston into the stop element such that the seal is inserted into the stop element at the seal protecting section.
b) inserting the stop element with the piston into a receptacle in the cylinder housing until it contacts a contact area of the stop element at a counter stop area of the cylinder housing, and
c) fastening at least one lid element to the cylinder housing with simultaneously an axial pre-stressing of the stop element in a direction of the pressure cylinder section.

Assignees

• Schaeffler Technologies Ag

Inventors

• Malitourne Jerome
• Man Laszlo

Classifications

• F16D2300/08

  Details or arrangements of sealings not provided for in group F16D3/84 · CPC title

• F16D25/088

  the line of action of the fluid-actuated members being distinctly separate from the axis of rotation · CPC title

• F16D2025/081

  Hydraulic devices that initiate movement of pistons in secondary cylinders for actuating clutches, i.e. primary cylinders · CPC title

• F15B7/08 Primary

  Input units; Master units · CPC title

• F16D25/12

  Details not specific to one of the before-mentioned types · CPC title