CN206299793U - Pressure cylinder unit, such as a clutch actuator, having a conically shaped support ring - Google Patents

Abstract

The utility model relates to a sealing assembly (1) for a pressure cylinder unit (10). The sealing assembly has a sealing element (2). The sealing element has an annular flange section (3). The flange section is provided with A plurality of sealing lips (5), which point in a common radial direction and each form a sealing surface (4) intended to bear against the pressure piston (11) or the housing (12), and the sealing assembly has a support Ring (6), the support ring is arranged on the flange section (3) supported by the radial side facing away from the sealing surface (4) and spaced radially from the sealing surface (4), wherein the support ring ( 6) In the unloaded state, it is conically formed with a support surface (7) that rests against the flange section (3) during operation; the utility model also relates to a pressure seal with such a sealing assembly (1). A cylinder unit (10), such as a clutch master cylinder.

Description

Pressure cylinder units with conically shaped support rings, such as clutch master cylinders

technical field

The utility model relates to a sealing assembly for a pressure cylinder unit, the sealing assembly is preferably used for actuating a clutch, the sealing assembly has a sealing element, the sealing element has an annular flange section, the flange The section is provided with a plurality of sealing lips, which point in the common radial direction of the sealing element and each form a sealing surface intended to bear against the pressure piston or the housing of the cylinder unit, and the The sealing element has a support ring which is arranged on the collar section supported by a radial side of the sealing element facing away from the sealing surface and spaced radially from the sealing surface. . Furthermore, the invention relates to a pressure cylinder unit per se, which is preferably designed as a clutch master cylinder or clutch slave cylinder and has such a sealing arrangement.

Background technique

Sealing assemblies of this type are sufficiently known from the prior art. Thus, for example, DE 10 2013 200986 A1 discloses a sealing assembly for a piston-cylinder unit having an annular seal with a static sealing lip and a moving sealing lip, which are connected to each other. The seal is received in a receptacle having at least one peripheral wall part and at least one axial wall part, and the seal is radially supported on the peripheral wall part with a static sealing lip in the receptacle. The moving sealing lip rests in a slidable manner against a further wall part adjoining the receptacle, and the axial end of the static sealing lip can rest against the axial wall part. Furthermore, means are provided for reducing twisting of the seal at the axial end region of the static sealing lip and/or at the axial wall.

Sealing assemblies are thus known from the prior art, which are also used in particular in clutch systems. Especially in the field of these pressure cylinder units (often configured as clutch master cylinders (English: "Clutch Master Cylinder"/CMC) it has proven to be disadvantageous that the use of relatively low-value fluid media in the use of these pressure cylinder units may Uncomfortable noise growth occurs due to the sliding of the sealing elements against each other on the corresponding housing or pressure piston. Especially at operating temperatures of approximately 80° C. or above, such movement noises are often generated, which can be detected by The user of the motor vehicle perceives it as uncomfortable. In this case, relatively high friction usually also occurs in the region of the sealing surfaces at the same time.

Utility model content

It is therefore the object of the present invention to eliminate the disadvantages known from the prior art and in particular to provide a sealing arrangement which also ensures that the pressure cylinder unit is as noise-free as possible when using relatively low-value fluid media running.

According to the invention, this object is achieved in that the support ring in the unloaded state (of the seal assembly) is shaped conically (that is, obliquely relative to the axial direction of the seal assembly) so that it bears against the Support surface on the flange section.

As a result, the sealing assembly rests with its flange section on the piston or the housing as uniformly as possible in a sealing manner during operation, during which the sealing assembly is pressed against the pressure piston and the housing with a certain preload. In the radial intermediate cavity between the bodies. The conical configuration of the support ring significantly improves the noise behavior, since in all operating states the area adjoining the sealing lip comes into contact with the housing or the pressure piston.

Further advantageous embodiments are claimed in the dependent claims and explained in detail below.

The collar section functions particularly efficiently if it is also connected to the base body of the sealing element and is elastically deformable in the radial direction.

Furthermore, it is also advantageous in this context if the collar section is formed in one piece with the base material. As a result, the sealing element can be produced overall particularly cost-effectively.

It is also expedient if the flange section is made of an elastic/elastically deformable plastic material, for example an elastomer, which is preferably suitable as sealing medium, since this advantageously influences the sealing effect. The support ring is also advantageously made of an elastic/elastically deformable plastic material, such as an elastomer, a thermoplastic or a thermoset.

It is also advantageous if the flange section is designed with its axial extension larger in the unloaded state than the support ring with its axial extension (in this unloaded state). This prevents the support ring, which is preferably made of a plastic material different from the flange section or the sealing element, from coming into contact with areas on the housing or on the pressure piston. In particular, wear of the support ring material is thereby avoided.

The support ring acts particularly effectively on all numbers of sealing lips if the flange section is supported by the support surface over its entire axial extent in the loaded state of the seal arrangement.

It is also advantageous if the flange section is configured/runned obliquely to the axial direction of the sealing element in the unloaded state, so that the sealing element bears particularly effectively and stably against the pressure piston or the sealing element during operation. Corresponding contact surfaces on the housing.

The sealing is achieved particularly effectively if the supporting surface is configured/curved in such a way that the supporting surface increases in its size/diameter going out from the base body of the sealing element towards the free end of the flange section. .

Furthermore, the present invention also relates to a pressure cylinder unit, which has a housing; a pressure piston of a pressure chamber; and a sealing assembly according to at least one of the previously described embodiments, which is arranged in such a way that the pressure chamber has a aspects) are sealed. As a result, the pressure cylinder unit is also designed particularly efficiently.

In this case, the pressure-cylinder unit is preferably designed as a clutch master cylinder or more preferably as a clutch slave cylinder.

It is also advantageous if the flange section is configured and supported by the support ring in such a way that, depending on the operating temperature of the pressure cylinder unit, the flange section has a number and/or contact force with its sealing lips. It bears variably against the pressure piston or the housing. As a result, the sealing effect can be controlled particularly effectively as a function of the operating temperature of the pressure-cylinder unit.

In this context, it is also expedient if the flange section is configured and supported by the support ring in such a way that the flange section at an operating temperature of the pressure cylinder unit between -60° C. and -30° C. , preferably at an operating temperature of approximately -40°C, only a part of the sealing lips rests sealingly against the pressure piston or the housing via their sealing surfaces, preferably with both sealing surfaces of the two sealing lips, while at least one The further sealing lip (with its sealing surface) is arranged at a distance from the pressure piston or the housing at this operating temperature/operating temperature range.

Furthermore, it is advantageous if the flange section is configured and supported by the support ring in such a way that the flange section at an operating temperature of the pressure cylinder unit between 0° C. and 40° C., preferably at approximately room temperature/approx. At an operating temperature of 15°C, only a part of these sealing lips bears sealingly against the pressure piston or the housing via their sealing surfaces, preferably with both sealing surfaces of the two sealing lips, while at least one other sealing lip ( with its sealing surface) at the operating temperature/range at a distance from the pressure piston or the housing.

It is also advantageous if the flange section is configured and supported by the support ring in such a way that the flange section at an operating temperature of the cylinder unit between +40° C. and +100° C., preferably at approximately 80° C. At an operating temperature of ° C., all sealing lips, preferably three sealing surfaces of three sealing lips, bear sealingly against the pressure piston or the housing via their sealing surfaces. As a result, a particularly low-noise design and temperature-independent sealing behavior can be achieved.

Furthermore, it is useful that the flange section rests with its sealing lip on the inner peripheral surface of the housing in a sealing manner, that is to say fluidically, preferably hydraulically, since in this region the seal works particularly effectively.

In other words, it is thus provided according to the invention that a conical abutment/support surface is provided on a so-called Energizer (support ring) of the seal assembly/primary seal assembly/primary seal and is formed by This conical configuration of the energizer. As a result, the energizer, which presses the sealing lip onto the housing, is configured conically and is modified in such a way that it only rests with the sealing lip on the housing and is no longer connected to another The contact area is snapped.

Description of drawings

Now, explain the utility model in detail below according to accompanying drawing.

The accompanying drawings show:

Figure 1 shows a longitudinal sectional view of a pressure cylinder unit according to the invention according to a preferred embodiment, in which a seal assembly according to the invention is used, wherein the pressure cylinder unit can be particularly well identifying the location of, inter alia, said sealing assembly;

Figure 2 shows a schematic longitudinal section of the seal assembly used in Figure 1, wherein said seal assembly with its sealing element and support ring is shown in an unloaded state in which The seal assembly is not yet inserted between the surfaces of the housing of the pressure cylinder unit and the surfaces of the pressure piston which are schematically indicated in dashed lines;

FIG. 3 shows a longitudinal section through the seal assembly according to FIG. 2, wherein the seal assembly is now in a loaded state, in which state the seal assembly is clamped between the outer peripheral side of the pressure piston and the inside of the housing in the radial intermediate space between them and bears with their flange sections in a sealing manner against the inner peripheral surface of the housing; and

Figures 4-6 show graphs of the extrusion pressure of the sealing surfaces of different sealing lips as a function of operating temperature (Figure 4 at -40°C, Figure 5 at room temperature (RT) and Figure 6 at 80°C) and Different pressure values in the pressure chamber are shown relative to the surroundings.

These figures are only schematic and are only used for the understanding of the present invention. The same elements are provided with the same reference numerals.

detailed description

The structure of the sealing arrangement 1 according to the invention can be seen particularly well in FIG. 3 . The sealing arrangement 1 is here in a loaded state in which it is pressed/squeezed into the radial intermediate space 15 between the housing 12 of the pressure cylinder unit 10 and the pressure piston 11 . The sealing arrangement 1 has, on the one hand, an annular sealing element 2 . The sealing element 2 again has an annular base body 8 . A collar section 3 is integrally formed on the axial end side of the base body 8 in one piece. The collar section 3 also extends continuously annularly along the entire circumference of the base body 8 . The flange section 3 extends substantially in the axial direction away from the base body 8 and is therefore designed as a strip/ring strip protruding from the base body 8 in the axial direction. Furthermore, the sealing element 2 /flange section 3 and the base body 8 are produced from an elastically deformable plastic material.

On a radial side of the flange section 3 , here on the radially outer peripheral side 18 , three sealing lips 5 are formed on the flange section 3 . These sealing lips 5 are each formed as projections, also referred to as projections, which form planar annular sealing surfaces 4 extending outward in the radial direction. In the loaded state of the sealing arrangement 1 according to FIG. 3 , the sealing lip 5 bears either fully or partially sealingly against the inner peripheral surface 14 of the housing 12 , depending on the operating temperature prevailing in the cylinder unit 10 . In this case, however, it must always be ensured that at least one sealing lip 5 with its sealing surface 4 , or that there are two sealing lips 5 with their sealing surfaces 4 , rest against the inner peripheral surface 14 in a hydraulic-tight manner.

In the stated loaded state of the sealing device 1 , a support ring 6 rests flat on the radial side of the flange section 3 facing away from the sealing lip 5 and forms a support surface 7 which faces away from the The radial side of the sealing lip 5 , here radially inwardly, supports the collar section 3 .

Furthermore, FIG. 2 shows the sealing assembly 1 in the unloaded state, wherein the sealing element 2 and the support ring 6 are not pushed into the intermediate space 15 as in FIG. 3 , but are relaxed without External operating loads and pre-clamping forces come into play. The support ring 6 is again trapezoidal in the unloaded state. In particular, the support surface 7 is configured/extends conically. In other words, the support surface 7 of the support ring 6 extends obliquely, ie substantially at approximately 5° to 20°, as viewed in the axial direction of the seal assembly 1 . The flange section 3 also extends obliquely in this unloaded state with respect to the axial direction of the seal arrangement 1 .

The axial extent of the support surface 7 , here even the entire axial extent of the support ring 6 , in this unloaded state is smaller than the axial extent of the flange section 3 in this unloaded state away from the base body 8 . In the loaded state according to FIG. 3 , the support ring 6 and the flange section 3 are again deformed/arranged relative to each other in such a way that the support ring 6 is formed over its entire axial extension/length with its support surface 7 The flange section 3 is supported radially from the inside. Here, the conical extension of the support surface 7 is selected in such a way that the support ring 6 moves away from the base body 8 in the axial direction (in such a direction that the flange section 3 also moves away from the base body 8 extend away) expand/widen/increase in outer diameter.

A particularly suitable temperature-dependent contact of the sealing surface 4 of the individual sealing lip 5 (at a constant pressure in the pressure chamber 13 ) on the housing 12 is achieved by the conical deformation of the support ring 6 in the unloaded state. , this abutment is schematically illustrated in the diagrams in FIGS. 4 to 6 . In this case, the flange section 3 is configured and supported by the support ring 6 in such a way that the flange section 3 operates at an operating temperature of −40° C. (in the first operating state) of the pressure cylinder unit 10 and the pressure Under the pressure of 40 bar in the cavity 13 (Fig. 4; solid line), the sealing surfaces 4 of the two sealing lips 5 (the first sealing lip 5a and the second sealing lip 5b) abut against the housing 12 in a sealing manner, while The other sealing lip 5 (third sealing lip 5 c ) is arranged with its sealing surface 4 at this operating temperature and (in the pressure chamber 13 ) at this pressure at a distance from the housing 12 or is arranged depressurized relative thereto. The friction force occurring between flange section 3 and housing 12 is 19N at these values. At the same time, the flange section 3 is also designed and supported by the support ring 6 in such a way that the flange section 3 has an operating temperature of 15° C. (in the second operating state) and a pressure of the pressure cylinder unit 10 Under the pressure of 40 bar in the chamber 13 (Fig. 5; solid line), the sealing surfaces 4 of the two sealing lips 5 (first and second sealing lips 5a, 5b) are also sealed against the housing 12, while The other sealing lip 5 (third sealing lip 5c) is arranged with its sealing surface 4 at the operating temperature and at the pressure (in the pressure chamber 13) at a distance from the housing 12 or is arranged depressurized relative thereto. . The friction force occurring between flange section 3 and housing 12 is 18N at these values. Furthermore, the flange section 3 is also designed and supported by the support ring 6 in such a way that the flange section 3 operates at 80° C. (in the third operating state) of the cylinder unit 10 At a temperature and a pressure of 40 bar in the pressure chamber 13 (FIG. 6; solid line), all sealing surfaces 4 of the three sealing lips 5 (first, second and third sealing lips 5a to 5c) bear sealingly against the on the housing 12. The friction force occurring between flange section 3 and housing 12 is 23N at these values.

The flange section 3 is also designed and supported by the support ring 6 in such a way that the flange section 3 is at an operating temperature of -40° C. (in the fourth operating state) of the pressure cylinder unit 10 and the pressure chamber 13 at a pressure of 20 bar ( FIG. 4 ; dotted line), and at an operating temperature of 15° C. (in the fifth operating state) of the pressure cylinder unit 10 and at a pressure of 20 bar in the pressure chamber 13 ( FIG. 5 ; dashed line), the sealing face 4 of only one sealing lip 5 (first sealing lip 5a) bears sealingly against the housing 12, while the other sealing lips 5 (second and third sealing lips 5b, 5c) At this operating temperature and this pressure, its sealing surface 4 is arranged at a distance from the housing 12 or is arranged pressure-free relative to the housing. In addition, the flange section 3 is also designed and supported by the support ring 6 in such a way that the flange section 3 has an operating temperature of 80° C. (in the sixth operating state) and a pressure of the pressure cylinder unit 10 At a pressure of 20 bar in the chamber 13 (FIG. 6; dotted line), all sealing surfaces 4 of the three sealing lips 5 (first, second and third sealing lips 5a to 5c) bear sealingly against the housing 12 on.

Again, the flange section 3 is configured and supported by the support ring 6 in such a way that the flange section 3 operates at an operating temperature of -40° C. (in the seventh operating state) of the pressure cylinder unit 10 and At a pressure of 0 bar in the pressure chamber 13 ( FIG. 4 ; dotted line), and at an operating temperature (in the eighth operating state) of the pressure cylinder unit 10 of 15° C. and a pressure of 0 bar in the pressure chamber 13 ( FIG. 5 ; dotted line), the sealing surface 4 of only one sealing lip 5 (first sealing lip 5a) bears sealingly on the housing 12, while the other sealing lip 5 (second and third sealing lip 5b , 5c) with its sealing surface 4 at this operating temperature and this pressure (in the pressure chamber 13 ) is arranged at a distance from the housing 12 or is arranged without pressure relative to the housing. In addition, the flange section 3 is also designed and supported by the support ring 6 in such a way that the flange section 3 has an operating temperature of 80° C. (in the ninth operating state) and a pressure of the pressure cylinder unit 10 At a pressure of 0 bar in the chamber 13 (FIG. 6; dotted line), the sealing surfaces 4 of the two sealing lips 5 (first and second sealing lips 5a, 5b) bear sealingly against the housing 12, The other sealing lip 5 (third sealing lip 5 c ), however, is arranged with its sealing surface 4 at this operating temperature and at this pressure at a distance from the housing 12 or is arranged depressurized relative thereto.

Every other region of the flange section 3 is always arranged spaced apart from the housing 12 in these operating states.

For the sake of completeness it is mentioned that the support ring 6 is likewise produced from an elastically deformable plastic material which is a different material than the material of the sealing element 2 .

The pressure cylinder unit 10 according to the invention as a whole can be seen particularly well in FIG. 1 . In this case, it is a pressure cylinder unit 10 in the form of a clutch master cylinder 9 , the pressure piston 11 of which is movably connected in a customary manner to a clutch pedal of the motor vehicle. A pressure piston 11 is mounted displaceably in the housing 12 in the axial direction of the housing 12 , between which a fluidic, ie hydraulic, pressure chamber 13 is formed in a conventional manner. Several seals are arranged on the pressure piston 11 , wherein a primary seal 16 is formed as the sealing arrangement 1 according to the invention. Furthermore, the pressure piston 11 also has a second seal in the form of a secondary seal 17, wherein not only the primary seal but also the secondary seals 16, 17 have the task of securing the pressure chamber 13 relative to the surrounding environment. Sealed. The sealing arrangement 11 is in turn clamped/pressed into the radial intermediate space 15 between the radially outer side/outer peripheral side of the pressure piston 11 and the inner peripheral surface 14 of the housing 12 in the manner already described. In particular, the sealing element 2 with the support ring 6 is fixed in the axial direction in the pressure piston 11 and rests slidingly with the flange section 3 with its sealing lip 5 on the inner peripheral surface 14 .

In other words, a seal assembly 1 is thus provided which has a support ring 6 also referred to/designed as an "energizer" with a conical profile, so that the plastic seal (primary The extrusion force outside the sealing lip 5 of the seal 16) also further reduces the extrusion force and friction of the sealing lip 5.

List of reference signs

1 seal assembly

2 sealing element

3 Flange section

4 sealing surface

5 sealing lip

5a First sealing lip

5b Second sealing lip

5c Third sealing lip

6 support ring

7 Support surface

8 substrates

9 clutch master cylinder

10 pressure cylinder unit

11 Pressure piston

12 housing

13 pressure chamber

14 inner peripheral surface

15 intermediate cavity

16 Primary seal

17 Secondary seal

18 Peripheral side.

Claims (10)

1. Sealing assembly (1) for a pressure cylinder unit (10), said sealing assembly having a sealing element (2) having an annular flange section (3) which A plurality of sealing lips (5) are provided, which point in a common radial direction and each form a sealing surface (4) intended to bear against a pressure piston (11) or housing (12), And the sealing assembly has a support ring (6), which is supported by a radial side facing away from the sealing surface (4) and is arranged radially spaced apart from the sealing surface (4). On the flange section (3), it is characterized in that the support ring (6) is conically shaped in the unloaded state with a support which bears against the flange section (3) during operation face (7). 2. The sealing assembly (1) according to claim 1, characterized in that the flange section (3) is connected to the base body (8) of the sealing element (2) and is elastically deformable in radial direction . 3 . The sealing arrangement ( 1 ) according to claim 2 , characterized in that the flange section ( 3 ) is formed in one piece with the base body ( 8 ) material. 4 . 4. The sealing assembly (1 ) according to any one of claims 1 to 3, characterized in that the flange section (3) is made of an elastic plastic material. 5. The sealing arrangement (1) according to any one of claims 1 to 3, characterized in that the flange section (3) is configured with respect to its axial extension in the unloaded state larger than the support ring (6) in its axial extension. 6. The sealing assembly (1) according to any one of claims 1 to 3, characterized in that the flange section (3) extends over the entire axial extent of the sealing assembly (1) It is supported by the support surface (7) under the load state. 7. The sealing assembly (1) according to any one of claims 1 to 3, characterized in that the flange section (3) is in the unloaded state relative to the sealing element (2) The axial direction extends obliquely. 8. Pressure cylinder unit (10), which has a housing (12), has a fluid pressure chamber ( 13) with a pressure piston (11) and a sealing assembly (1) according to any one of claims 1 to 7, which is arranged in such a way that the pressure chamber (13) is be sealed. 9. The cylinder unit (10) according to claim 8, characterized in that the flange section (3) is configured and supported by the support ring (6) in such a way that the flange Depending on the operating temperature of the pressure cylinder unit (10), the flange section rests variably against the pressure piston (11) or the housing by means of its sealing lips (5) in number and/or in contact force body (12). 10. The pressure cylinder unit (10) according to claim 8 or 9, characterized in that the flange section (3) rests sealingly against the housing (12) with its sealing lip (5) on the inner peripheral surface (14).