Vehicle brake system pressure damper

Abstract

The invention relates to a vehicle brake system pressure damper (10) for damping pressure pulses of a hydraulic fluid of a vehicle brake system, having a fluid chamber (32) for accommodating the hydraulic fluid and a damping chamber (34) for accommodating an elastic medium, wherein a partition element (18) for sealing is provided between the fluid chamber (32) and the damping chamber (34), wherein the fluid chamber (32) is defined by a first wall (36) which is located radially inward, and the partition element (18) is seated against the first wall (36) with a sealing flange (38) which is located radially inward.

Description

TECHNICAL FIELD

[0001] The invention relates to a vehicle brake system pressure damper for damping pressure pulses of a hydraulic fluid of an associated vehicle brake system, having a fluid chamber for accommodating the hydraulic fluid and a damping chamber for accommodating an elastic medium, wherein a partitioning element for sealing is provided between the fluid chamber and the damping chamber. BACKGROUND

[0002] Vehicle brake systems, in particular hydraulic brake systems, are used to slow down the driving speed of vehicles such as passenger cars and trucks. During operation of such brake systems various dynamic effects occur, in addition to which pressure pulses arise which lead to oscillations and thus to undesired noises and vibrations. In order to minimize such oscillations, pressure dampers are installed. The pressure dampers comprise a damping chamber in which a hydraulic pressure is applied. The pressure is transmitted via the hydraulic fluid in the pipes.

[0003] Pressure dampers are known which have a pot-shaped or cup-shaped diaphragm, so-called diaphragm dampers. The diaphragm is usually made of an elastomer, that is to say a plastic which is fixed in shape but elastically deformable. The diaphragm separates the damping chamber from the fluid chamber which is supplied with hydraulic fluid under hydraulic pressure. In the usual known manner, a gaseous and thus compressible medium is located in the damping chamber. For reasons of simplifying the overall arrangement, air is usually used as the medium. SUMMARY

[0004] It is an object of the invention to provide a vehicle brake system pressure damper which is manufactured cost-effectively and which is reliable in operation for damping pressure pulses and vibrations in a vehicle brake system.

[0005] According to the inventive approach, a vehicle brake system pressure damper for damping pressure pulses of a hydraulic fluid of an associated vehicle brake system is provided, having a fluid chamber for accommodating the hydraulic fluid and a damping chamber for accommodating an elastic medium, wherein a partitioning element for sealing is provided between the fluid chamber and the damping chamber. Furthermore, in the vehicle brake system pressure damper, the fluid chamber is defined by a first wall which is located radially inward, and the partitioning element bears against the first wall with a sealing flange which is located radially inward.

[0006] With the technical solution according to the application, a support or lip is formed, which is pushed from the inside towards the first wall when the pressure in the fluid chamber increases and in this way has a stronger sealing effect there. This ensures that the separation part cannot be penetrated by hydraulic fluid located in the fluid chamber and under high pressure. Penetration can lead to a leak between the fluid chamber and the damping chamber and in this way is reliably avoided. Here, this technical solution can be implemented in particular in such a way that the separation part does not need to be pre-vulcanized or vulcanized at the first wall. Such vulcanization is a relatively expensive manufacturing step and is avoided according to the application.

[0007] According to an advantageous refinement of the technical solution according to the application, the hydraulic fluid is directed into the fluid chamber according to the inflow direction, wherein the first wall is directed in the direction along the inflow direction and the sealing flange is directed in the direction opposite the inflow direction. The sealing flange according to the application then projects into the fluid chamber in the opposite direction to the inflow of the hydraulic fluid and in this way forms an inner wall surface there, onto which the pressure present in the fluid chamber acts.

[0008] The sealing flange preferably has a radial thickness between a quarter and a half of its axial length, preferably a third of its axial length. Such a sealing flange has a relatively thin wall or is configured in the form of a layer, which can be pressed against the first wall over a large area and easily by the hydraulic pressure in the fluid chamber.

[0009] The first wall is particularly preferably cylindrical, that is to say circular in cross section. This wall surrounds the fluid chamber in the shape of a circular ring, so that almost equally large hydraulic pressures act on all wall sections.

[0010] Furthermore, such a vehicle brake system pressure damper is provided with a radially outer second wall, which is likewise circular in cross section and concentric to the first wall, and the separation part is provided with a second sealing flange, which is arranged radially between the first wall and the second wall. The separation part according to the application is thus additionally held in a sealing manner between the first wall and the second wall and at the same time is held positionally fixed.

[0011] The second wall is particularly preferably formed by a cup-shaped damper housing, which delimits the damping chamber on the outside, and the first wall is formed by an annular sleeve, which is attached to the damper housing on the end side. The sleeve and the damper housing are easily assembled together with one another, wherein the separation part according to the application is easily inserted between them.

[0012] The partitioning component is also preferably configured as a thin-walled elastomer component. Between the fluid chamber and the damping chamber, the elastomer component forms a movable flexible membrane which can reversibly follow pressure changes occurring there. Moreover, the elastomer component can advantageously itself be compressible and thus itself exert a targeted damping effect.

[0013] Alternatively or additionally, the partitioning component is advantageously configured in the shape of a cup and has a cup wall and a cup bottom, wherein the damping chamber substantially radially surrounds the cup wall on the outside. Thus, a relatively large cup wall produces a relatively large effective surface with a relatively small structural space requirement and thus with a correspondingly large damping effect.

[0014] The fluid chamber preferably has an inflow opening for the inflow of hydraulic fluid, the damping chamber is preferably delimited on the outside by a damper housing and the partitioning component is advantageously supported on the damper housing with its partitioning component section which is opposite the inflow opening. When the pressure in the fluid chamber rises and is diverted into the damping chamber, the partitioning component supported on the damper housing is pressed against the damper housing on the one hand at the so-called partitioning component section and on the other hand with its sealing flange according to the invention which is located at the inlet is pressed against the first wall located there. The sealing effect achieved according to the invention is thus further improved.

[0015] It is also a specific object of the application to use such a vehicle brake system pressure damper according to the application to dampen pressure pulses of the hydraulic fluid of the associated vehicle brake system. BRIEF DESCRIPTION OF DRAWINGS

[0016] Embodiments of the technical solution according to the application are explained in more detail below with reference to the attached schematic drawings. The drawings show:

[0017] Figure 1 is a longitudinal sectional view of an embodiment of a vehicle brake system pressure damper according to the application. DETAILED DESCRIPTION

[0018] The diagram shows a vehicle brake system pressure damper 10, in which a cup-shaped or pot-shaped damper housing 12 is constructed with a cylindrical housing wall 14 and a housing bottom 16 which closes the housing wall 14 at an end region. In the damper housing 12 there is also a cup-shaped partition member 18 which is likewise in the form of a thin-walled elastomer component, which is provided with a cylindrical cup wall 20 and a circular cup bottom 22 which closes the cup wall at the region of the housing bottom 16. The cup wall 20 and the cup bottom 22 form a partition member section, wherein the cup bottom 22 is supported in a planar abutment at the centre of the housing bottom 16. Opposite the cup bottom 22, the partition member 18 has a flange region 24, by means of which the partition member 18 is abutted against a sleeve 26. The sleeve 26 is inserted into the damper housing 12 at an end face of the housing wall 14 which is opposite the housing bottom 16 and closes the damper housing 12 there in a fluid-tight manner. In the centre of the sleeve 26 a circular inflow opening 28 is formed, by means of which, as is not shown in detail here, hydraulic fluid can flow in an inflow direction 30 into the interior of the cup wall 20 and further into a cylindrical fluid chamber 32 which is formed by the cup wall. Hydraulic fluid can also leave the fluid chamber again through the inflow opening 28 counter to the inflow direction 30.

[0019] Opposite the inflow direction 30, radially outside the fluid chamber 32 and radially outside the cup wall 20 which delimits the fluid chamber, there is a hollow-cylindrical damping chamber 34. In the damping chamber 34 there is a gas, at present air, so that the damping chamber is compressible and the cup wall 20 of the elastic partition member 18 can be moved or deformed in the radial direction. In this case, the hydraulic fluid in the fluid chamber 32 has a relatively high pressure, which is transmitted by the partition member 18 to the gas which is present in the damping chamber 34. Here, in order to reliably seal the partition member between the fluid chamber 32 and the damping chamber 34 during the service life of the vehicle brake system pressure damper 10, the sleeve 26 is provided with a hollow-cylindrical first wall 36 which is directed in the axial direction to the inflow direction 30, against which the partition member 18 abuts with a sealing flange 38 at the radially inner side. The sealing flange 38 faces away from the inflow direction 30 starting from the cup wall 20 and has a radial thickness 40 which is equal to one third of its axial length 42.

[0020] A second wall 44 which is formed by the housing wall 14 is located radially outside the first wall 36 which is formed by the sleeve 26, between which first and second walls the partition member 18 with a second sealing flange 46 is located. The second sealing flange 46 is clamped here in the radial direction between the first wall 36 and the second wall 44 and is held in this way in a force-transmitting connection and also at its end in a form-fitting connection.

[0021] As the pressure in the fluid chamber 32 increases, the cup wall 20 is radially outwardly compressed by the hydraulic fluid located there, and simultaneously axially outwardly compressed by its end region. This presses the cup bottom 22, supported on the housing bottom 16, against the damper housing 12, and simultaneously compresses the sealing flange 38 and the second sealing flange 46 of the separating member 18 against the flow direction 30, thus axially pressing them towards the sleeve 26. This further improves the sealing effect of the sealing flange 38, which is otherwise pressed radially inward against the first wall 36, and also further improves the sealing effect of the second sealing flange 46.

Claims

1. A vehicle braking system pressure damper (10) for suppressing pressure pulses of hydraulic fluid in a vehicle braking system, the vehicle braking system pressure damper having a fluid chamber (32) for containing hydraulic fluid and a damping chamber (34) for containing an elastic medium, wherein a sealing partition (18) is provided between the fluid chamber (32) and the damping chamber (34). in, The fluid chamber (32) is defined by a radially inwardly cylindrical first wall (36), and the partition member (18) abuts against the first wall (36) with a radially inwardly positioned sealing flange (38). The feature is that it has a second wall (44) located radially outward, which is also cylindrical in cross-section and concentric with the first wall (36), and the partition member (18) has a second sealing flange (46) arranged radially between the first wall (36) and the second wall (44).

2. The vehicle braking system pressure damper according to claim 1, characterized in that, The hydraulic fluid is guided into the fluid chamber (32) according to the inflow direction (30), wherein the first wall (36) points in the direction along the inflow direction (30) and the sealing flange (38) points in the opposite direction to the inflow direction (30).

3. The vehicle braking system pressure damper according to claim 2, characterized in that, The sealing flange (38) has a radial thickness (40) that is between one-quarter and one-half of the axial length (42) of the sealing flange.

4. The vehicle braking system pressure damper according to claim 3, characterized in that, The radial thickness is one-third of the axial length of the sealing flange.

5. The vehicle braking system pressure damper according to claim 1, characterized in that, The second wall (44) is formed by a cup-shaped damper housing (12) that defines the damping chamber (34) on the outside, and the first wall (36) is formed by an annular sleeve (26) fitted on the damper housing (12) at the end.

6. The vehicle braking system pressure damper according to any one of claims 1 to 5, characterized in that, The separating component (18) is a thin-walled elastomeric component.

7. The vehicle braking system pressure damper according to any one of claims 1 to 5, characterized in that, The partition (18) is configured in the shape of a cup and has a cup wall (20) and a cup bottom (22), wherein the damping chamber (34) surrounds the cup wall (20) substantially radially on the outside.

8. The vehicle braking system pressure damper according to any one of claims 1 to 5, characterized in that, The fluid chamber (32) has an inflow opening (28) for hydraulic fluid to flow in, the damping chamber (34) is defined on the outside by a damper housing (12), and the partition member (18) is supported on the damper housing (12) with a partition member section opposite to the inflow opening (28).

9. The application of the vehicle braking system pressure damper (10) according to any one of claims 1 to 8, wherein the application is used to suppress pressure pulses of the hydraulic fluid of the vehicle braking system to which it belongs.

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