阅读说明：本技术 用于减振器的阻尼阀 (Damping valve for shock absorber ) 是由 S·海恩 A·科内泽维奇 J·罗塞勒 于 2019-08-15 设计创作，主要内容包括：一种用于减振器的阻尼阀,其包括带有环形沟槽的阻尼阀体,所述环形沟槽由用于至少一个阀盘的阀座面封边,其中在所述环形沟槽中布置有用于流入的阻尼介质的连接通道的至少一个排出开口,其中,所述环形沟槽具有C形的走向。(A damping valve for a shock absorber, comprising a damping valve body with an annular groove which is edge-sealed by a valve seat for at least one valve disk, wherein at least one outlet opening for a connecting channel for an inflowing damping medium is arranged in the annular groove, wherein the annular groove has a C-shaped course.)

1. Damping valve (1) for a shock absorber, comprising a damping valve body (5) with an annular groove (25) which is sealed by a valve seat surface (27) for at least one valve disk (29), wherein at least one outlet opening of a connecting channel (39) for an inflowing damping medium is arranged in the annular groove (25), characterized in that the annular groove (25) has a C-shaped course.

2. The damper valve according to claim 1, characterized in that the cover plate surface (41) of the damper valve body (5) has, radially outside the annular groove (25), an axial projection (43) with a support surface (45) which is loaded at least during a lifting movement of the valve disk (29) from the valve seat surface (27).

3. The damper valve according to claim 2, wherein the axial spacing of the support surface (45) from the cover plate surface (41) is less than the spacing of the seat surface (27) relative to the same cover plate surface (41).

4. Damping valve according to claim 2, characterized in that the support surface (45) is formed by a support strip (46).

5. The damper valve according to claim 2, characterized in that the support surface (45) is configured on an annular support strip (46) which defines a cavity (53).

6. A damper valve according to claim 5, characterised in that the recess (53) is an annular groove.

7. The damper valve according to claim 6, wherein the cavity (53) and the annular groove form a circular ring.

8. The damper valve according to claim 5, characterized in that a spacer (54) as part of the support strip (46) defines both the cavity (53) and the annular groove section (25).

9. A damper valve according to claim 6, characterised in that the outer support plate strip (55) of the recess (53) and the outer valve seat surface (57) of the annular groove (25) have the same diameter.

10. A damper valve according to claim 6, characterized in that the inner support web (59) of the cavity (53) and the inner valve seat surface (61) of the annular groove (25) have the same diameter.

11. Damping valve according to claim 5, characterized in that an outflow opening (63) to a working chamber (65) is formed in the recess (53), which outflow opening hydraulically connects in parallel a throttle opening (67) from the annular groove (25) into the same working chamber (65) in an outflow direction, wherein the recess (53) is closed off with respect to a working chamber (69) via which damping medium is supplied to the annular groove (25) via a connecting channel (21).

12. Damping valve according to claim 11, characterized in that a flow connection (71) is present between the cavity (53) and the annular groove (25), which flow connection constitutes a throttling cross-section.

Technical Field

The present invention relates to a damping valve for a shock absorber according to the preamble of claim 1.

Background

As is known in the art in accordance with a number of practical applications, a damping valve operates particularly low-noise when the valve disc is defined at a certain point to begin to rise from the valve seat surface. For this purpose, there are numerous valve configurations, such as, for example, an eccentric valve disk assembly, as described in DE 102017002566 a1, or a corrugated valve seat, as described in DE 102010040458 a1, which have different distances in the annular groove from the pressure center. Document JP 3123021B 2 discloses a cloverleaf arrangement of differently dimensioned, segmented valve seats which are formed completely separately from one another on the valve body. The greatest lifting force acts in the region of the greatest seating surface, so that a lifting movement of the valve disk is also carried out in this region.

The clover arrangement has the disadvantage of reducing the size of the face that exerts pressure on the valve disc. In principle, a larger annular groove is advantageous for the opening behavior, since it also provides a larger pressure-exerting surface, which tends to cause a greater opening force on the valve disk. The material strength of the valve disk can be increased because the opening force of the valve disk is in favorable proportion to the closing force of the valve disk due to the operating pressure. The greater material strength results in less stress in the valve disc and thus in a longer service life of the damper valve.

In this case, a damping valve according to DE 102014223086 a is also to be mentioned, in which the valve contact surface has an asymmetrical, elliptical course along the annular groove.

Disclosure of Invention

The object of the invention is to develop a damping valve which on the one hand has a large pressure application surface on the valve disk and on the other hand enables a defined opening point.

This object is achieved in that: the annular groove has a C-shaped course.

An asymmetrical pressure loading of the valve disk is thus achieved, which results in a lifting movement of one side of the valve disk. The lift-off characteristic is thus clearly determined.

In order to even more strongly limit the lifting movement of the valve disk, the cover plate surface of the damping valve body has, radially outside the annular groove, an axial projection with a support surface which is acted upon at least during the lifting movement of the valve disk from the valve seat surface. The support surface forms an inclined edge so that the valve disk can perform a rocking motion when lifted from the valve seat surface.

The opening behavior of the valve disk can be additionally influenced by: the distance between the supporting surface and the cover plate surface is smaller than the distance between the valve seat surface and the same cover plate surface.

Preferably, the support surface is formed by a support strip. The supporting strips form a sufficiently large supporting surface, wherein the supporting strips can also be constructed in sections.

According to an advantageous dependent claim, the support surface is formed on an annular support strip, which defines the recess. The recess is preferably an annular groove in order to achieve a greater length of the support surface.

To make maximum use of the available installation space, the separating webs not only define the recess but also the annular groove section.

To this end, it is helpful for the recess and the annular groove to form a ring.

When manufacturing the damping valve body in a forming method, it is meaningful to avoid transition areas when the outer support web of the recess and the outer valve seating surface of the annular groove have the same diameter.

In addition, it can be provided that the inner support webs of the recess and the inner valve seat surface of the annular groove have the same diameter.

Optionally, an outflow opening to the working chamber is formed in the recess, which outflow opening hydraulically connects in parallel a throttle opening in the outflow direction from the annular groove into the same working chamber, wherein the recess is closed off from the working chamber, via which damping medium is supplied to the annular groove via a connecting channel. A reduced pressure (minderdry) is additionally formed in the recess, which partially exerts a retaining force on the valve disk. Thus, a force pair is provided in the annular groove with an opening force and in the region of the recess with a holding force in order to apply a tilting moment to the valve disk.

In a further advantageous embodiment, a flow connection is present between the recess and the annular groove, which flow connection forms a throttle cross section. The holding force can be varied by the throttle cross section.

Drawings

The invention is explained in detail in the following description of the figures.

FIG. 1 is a view of the installation of a damping valve in a shock absorber;

FIG. 2 is a side view of the damping valve body according to FIG. 1;

FIG. 3 is a top view of the damping valve body;

FIG. 4 is a simplified top view of a damping valve body;

FIG. 5 is a damping valve body having an annular groove and a cavity.

Detailed Description

Fig. 1 shows a sectional illustration of a damping valve 1 for a shock absorber 3. This embodiment describes a particularly simple application, so that such a damping valve 1 can also be considered as a piston valve or can be considered in connection with an adjustable damping valve device.

The damping valve 1 comprises a damping valve body 5 which is clamped between the bottom 7 of the outer cylinder 9 and the inner cylinder 11. For this purpose, the damping valve body 5 has support parts 13, between which radial channels 15 are arranged. Said radial channels 15 connect a storage chamber 17 filled with damping medium with a working chamber 19 inside the cylinder 11.

For this purpose, a connecting channel 21 is formed in the damping valve body 5, the outlet opening 23 of which opens into an annular groove 25. The annular groove 25 is sealed by a valve seat 27 for at least one valve disk 29. The pretension spring 31 exerts a closing force on the valve disk 29 against the valve seat 27. The pretension spring 31 is held by a spring retainer 33 connected to a fastening means 35, for example a fastening rivet. On the radially inner pitch circle of the annular groove 25, a plurality of axial connecting channels 37 are arranged, the outlet openings of which are directed toward the storage chamber 17 and are likewise at least partially covered by at least one valve disk 41.

When the damping medium is pressed into the reservoir chamber 17 by the inner cylinder 11 via the connecting channel 37 in the course of a spring movement of the wheel, not shown, the valve disk 41 then generates a damping force with the outlet opening 37 and thus forms a damping valve.

For the flow of the damping valve body from the reservoir chamber 17 to the annular groove 25, the valve seat 27 together with the valve disk 29 forms an open check valve, which should generally generate as insignificant a damping force as possible. Rather, the valve disk 29 should rise noiselessly and likewise close noiselessly.

Fig. 2 and 3 show the damping valve body 5 in a single part. As can be seen in particular from the plan view according to fig. 3, the annular groove 25 has a C-shaped course around the center of the damping valve body 5. It can also be seen that the connecting channel 21 preferably has an arcuate discharge opening 23 and is arranged in the circumferential direction between the support parts 13 of the damping valve body.

The annular groove 25 has a circumferential angle of more than 180 ° and less than 300 ° on the spring leg. However, if the vibration damper is used as an axial damper, i.e. the vibration damper and the support spring are separate components, the circumferential angle is at most 180 °. The piston rod of the spring leg usually has a larger cross section than the geometric dimensions, so that there is a sufficiently large discharge cross section relative to the annular groove in order to be able to compensate for the piston rod volume discharged by the cylinder by the damping medium flowing in.

From an overview of fig. 2 and 3, it can be seen that the cover plate surface 41 of the damping valve body 5 has an axial projection 43 with a support surface 45 radially outside the annular groove 25. The support surface 45 is loaded at least during the lifting movement of the valve disk 29 from the valve seat surface 27. Various variants are conceivable for the design of the support surface 45. Only the principle is shown here. The diameter of the damping valve body 5 and the circumferential angle of the annular groove 25 substantially determine the position of the support surface 45, which here is formed by the support web 46. The greater the radial distance from the annular groove 25, the smaller the force required for the lifting movement of the valve disk 29 from the valve seat surface 27, since the length of the lever arm of the hydraulic lifting force acting on the valve disk 29 corresponds to the length from the pressure center 47 determined by the annular groove 25 to the inclined edge 49 formed by the support surface 45.

As a further adjustment feature, the distance of the support surface 45 from the cover surface 41 can be used. If this distance is smaller than the distance of the valve seat 27 from the same cover surface, a greater lifting angle of the valve disk relative to the valve seat can be achieved, since the support surface 45 only exerts its effect after a certain lifting angle has been reached. But the inclined edge 49 moves from the support surface 45 to the end edge 41 of the annular groove 25.

In fig. 4, the damping valve body 5 shown in a plan view according to fig. 3 is shown in a simplified form in order to clearly show the displacement of the hydraulic center of pressure 47 onto the valve disk. For an annular groove 25 with a constant width and a circumferential angle of 360 °, the pressure point of the hydraulic pressure is in the center of the damping valve body 5. Ideally, the valve disk 29 performs a parallel lifting movement from the valve seat surface 27. In practice, however, this does not occur, since various influences cause the elastic valve disk 27 to perform a lifting movement at several points simultaneously and to open further without restriction.

The radial displacement of the hydraulic center of pressure 47 onto the valve disk 29 is achieved by the C-shaped annular groove 25. Radius value r for the inner and outer radii of the annular groove 25_a、r_iAnd the circumferential angle α determines the radial displacement, the displacement can then be accurately calculated.

h_A-A＝2/3×(r_a ²+r_a×r_i+r_i ²)/(r_a+r_i)×(sinα/α)

The damping valve 1 according to fig. 5 shows a variant of the embodiment according to fig. 1 to 4. An important difference is that the support surface 45 is formed on an annular support strip which defines the recess 53. The recess 53 is here an annular groove, wherein the recess 53 and the annular groove 25 form a circular ring. The section 54 of the support strip 46 defines not only a cavity but also an annular groove section.

The outer support plate strip 55 of the cavity 53 and the outer valve seating surface 57 of the annular groove 25 have the same diameter. The same principle applies to the inner support strip 59 and the inner valve seat surface 61, which have the same diameter. The two supporting webs 55, 59 have the same axial spacing relative to the cover plate surface 41.

At least one outflow opening 63 leading to a working chamber 65 in the inner cylinder 11 (fig. 1) is formed in the recess 53, which outflow opening hydraulically connects in parallel at least one throttle opening 67 in the outflow direction from the annular groove 25 into the same working chamber 65. As can be seen from fig. 5, the recess 53 does not have an axial connecting channel 21, such as the annular groove 25. The cavity 53 is thus closed off from the working chamber 69, via which damping medium is supplied to the annular groove 25 via the connecting channel 21. In this embodiment, the working chamber 69 is connected with the storage chamber 17.

Between the recess 53 and the annular groove 25 there is a flow connection 71 which constitutes a throttling cross section. For this construction principle, the pressure drop between the annular groove 25, the cavity 53 and the working chamber 65 in the cylinder 11 is used. The key is that less pressure is generated in the cavity 53 than in the annular groove 25. In this way, locally different lifting forces are achieved with conventional valve disks 29 with annular valve seats, which hydraulically produce a lifting force that deviates from the center axis.

When the flow connection 71 between the annular groove 25 and the recess 53 is closed and the outflow opening 63 is also omitted, for the lifting movement of the valve disk 29, an insufficient supply of the damping medium in the recess is caused by the pressure loading in the annular groove 25, i.e. a pressure reduction occurs. In combination with the overpressure in the annular groove 25, the centre of pressure 47 moves significantly radially outwards towards the annular groove. However, if the recess 53 is filled with damping medium by a crescent-shaped cross section on the inner diameter of the recess 53, an excessively abrupt effect of the opening movement of the valve disk 29 may occur. This effect depends significantly on the ratio of the size of the annular groove 25 to the size of the cavity 53.

This effect can be avoided by suitably designing the geometry of the throttling cross-section of the outflow opening 63 and the flow connection 71.

The hydraulic pressure ground displacement follows the following relationship:

h_A-A～1–A² _ZLD/(A² _ZLD+A² _ALD)

wherein A is_ZLDIs a throttling cross section between the annular groove and the concave cavity; a. the_ALDIs the cross section of the outflow opening in the working chamber of the cylinder.

It should also be noted with regard to the design of the damping valve 1 that the throttle cross section 71 between the annular groove 25 and the recess 53 and the cross section of the outflow opening 67 are components of a pre-opening cross section which determines the damping force when the valve disk 29 is still seated on the valve seat 27.

Determining an effective pre-opening cross-section according to the following equation

Where KD is the throttle opening in the outflow direction from the annular groove.

It is entirely suitable that the throttle opening 67 in the outer valve seat surface 57 of the annular groove 25 is configured in the region of maximum spacing from the recess 53 in order to minimize the adhesion effect of the valve disk 29 to the valve seat surface 27.

The two effects produced by the C-shaped annular groove and the throttle cross section of the recess 53 add vectorially and therefore allow a clear determination of the geometry.

List of reference numerals:

1 damping valve

3 vibration damper

5 damping valve body

7 bottom

9 outer cylinder

11 inner cylinder

13 support part

15 radial channel

17 storage chamber

19 working chamber

21 connecting channel

23 discharge opening

25 annular groove

27 seat surface

29 valve disk

31 pre-tightening spring

33 spring retainer

35 fastening rivet

37 connecting channel

39 discharge opening

41 cover plate surface

43 axial projection

45 bearing surface

46 support batten

47 center of pressure

49 inclined edge

51 end edge

54 division sheet

55 outer supporting plate strip

57 outer valve seating surface

59 inner support batten

61 inner valve seat surface

63 outflow opening

65 working chamber

67 throttle opening

69 working chamber

71 flow connection