WO2023031400A1

WO2023031400A1 - Damping valve device for a vibration damper

Info

Publication number: WO2023031400A1
Application number: PCT/EP2022/074452
Authority: WO
Inventors: Hartmut Rölleke; Jörg Rösseler; Stefan Liehmann; Mathias Balensiefer; Aleksandar Knezevic
Original assignee: Zf Friedrichshafen Ag
Priority date: 2021-09-06
Filing date: 2022-09-02
Publication date: 2023-03-09
Also published as: DE102021209777A1; DE102021209777B4

Abstract

The invention relates to a damping valve device (1) for a vibration damper (3), comprising a valve element (29) which has a variable diameter, which is held by a valve carrier (25) and which, starting from a passage position, assumes a throttle position depending on a flow rate of a damping medium within a throttle point (31) by means of a radial closing movement in the direction of a flow guide surface (33), wherein the valve element (29) comprises at least two legs (71, 73) which are movably mounted about a rotary bearing (75) which is designed independently of the valve carrier (25) guiding the valve element (29), wherein one leg (73) has a first bearing point (77) and the other leg (71) has a second bearing point (79) and these two bearing points (77, 79) form the rotary bearing (75), wherein the bearing point (77) of one leg (73) is formed by a radially slotted through-opening having a lateral surface which is at least partly curved in the pivot direction of the rotary bearing (75), wherein the lateral surface is a guide surface (81) for the bearing point of the other leg (71), wherein an extension (85) of the other leg (71) extending in the circumferential direction engages in the bearing point (77) via a slot (83) in the bearing point (77) and the extension (85) has a curved guide surface (87) which interacts with the guide surface (81) of the other leg (73), wherein the slot (83) has a circumferential angle of less than 180° in the region of the guide surface (87).

Description

Damping valve device for a vibration damper

The invention relates to a damping valve device for a vibration damper according to the preamble of patent claim 1.

DE 10 2016 210 790 A1 discloses a damping valve device that has a valve element with a variable diameter that executes a radial closing movement as a function of a flow rate within a throttle, as a result of which a throttle cross section of the throttle is changed.

The valve element has a transverse slit and is radially elastic. A limiting ring determines the maximum expansion of the valve element and also ensures a return movement of the valve element in the direction of its initial position, in which the maximum passage cross section of the throttle is also present.

In such a damping valve device, the reaction behavior of the valve element to a changing flow situation largely determines the quality of the damping valve device. The reaction speed and the size of the minimum throttle cross section play an important role here.

DE 10 2019 215 558 A1 discloses a throttle point whose valve element is formed by two curved legs which are connected to one another via a pivot bearing. This design of the valve ring offers the advantage that the material for the valve ring can be chosen more freely. On the other hand, such a valve element is significantly more complex in terms of assembly.

The object of the present invention consists in further developing a generic damping valve device with regard to the functional quality.

The object is achieved in that the bearing point of one leg is formed by a radially slotted through opening with a lateral surface that is at least partially curved in the pivoting direction of the pivot bearing, the lateral surface represents a guide surface for the bearing point of the other leg, with an extension of the other leg running in the circumferential direction engaging in the bearing point via a slot in the bearing point and the extension having a curved guide surface which interacts with the guide surface of the other leg, the slot in the Area of the guide surface has a circumferential angle of less than 180 °.

The advantage of the invention is that the two legs form a complete joint without an additional axle component, which is also secured radially and therefore cannot fall apart. It is easy to assemble, particularly because of the spare axle component.

A further advantage is achieved in that a side wall of the slot forms a stop surface for the other leg. Optionally, a stop on the valve carrier side can be dispensed with in order to define a maximum expansion movement of the valve element.

In a further advantageous embodiment, opposite end faces of the legs form a stop for a minimum diameter of the valve element. The faces can have a simple smooth profile. In addition, an optimal sealing function within the valve element is also achieved via this stop.

The two legs are preferably prestressed in the direction of the minimum diameter of the valve element by an annular restoring spring, which is supported on a support contour on the common top side of the legs, with at least the extension of the leg being aligned with the restoring spring without overlap. This spatial arrangement of the return spring relative to the extension simplifies the geometry of the legs in the area of the pivot joint.

Optionally, the pivot bearing can have an elastic stop element, in order to avoid impact noise on the one hand and to be able to use a setting parameter for the operating behavior of the throttle point on the other hand. For example, the stop element can be formed by an elastic insert of the pivot bearing. Depending on the desired damping force characteristic of the throttle point, you can select the insert.

Alternatively, the stop element can be formed by the extension of the leg, for example via a coating.

However, it can also be provided that the extension has at least one elastic partial section, so that the extension can be elastically deformed in the pivoting direction.

In a further advantageous embodiment, a stop contour of one leg and the elastic extension of the other leg form a second pivot bearing.

Another option is for the two legs to have an axial overlap in the region of the pivot bearing, with a first joint section having the extension in the through-opening in a first plane of the pivot bearing and a convexly curved end face of one leg having a complementary concavely curved end face of the other leg are performed. This double joint reduces the axial passage cross section through the valve element in the area of the swivel joint. The extension with the through-opening serves as a sort of radial pull-out protection, so that the two legs do not fall apart so easily during assembly. The overlapping at the two ends of the legs is used for optimum sealing against axial flow through the swivel joint.

It can also be provided that a separate joint element within the valve element has a rotary bearing with an extension at both ends, which engage in the through-opening of the adjacent leg. A significantly larger pivoting angle and possibly a radial offset between the two adjacent legs can be implemented. Optionally, the separate joint element can also form part of the outer lateral surface of the valve element.

The invention is to be explained in more detail on the basis of the following description of the figures.

It shows:

Fig. 1 Sectional view through a vibration damper in the area of the damping valve device

Fig. 2 throttle point according to Fig. 1 as an assembly

Fig. 3 Sectional view through the valve element according to Fig. 2

4 and 5 top view of the valve element according to FIG

6 and 7 alternative variant of the valve element

8 - 11 further alternative variant of the valve element

FIG. 1 shows a damping valve device 1 for a vibration damper 3 of any design, shown only in part. In addition to the damping valve device 1 , the vibration damper 3 includes a first damping valve 5 with a damping valve body designed as a piston 7 which is fastened to a piston rod 9 .

The damping valve body 7 divides a cylinder 11 of the vibration damper into a working chamber 13 on the piston rod side and a working chamber 13 remote from the piston rod; 15, both of which are filled with damping medium. In the damping valve body 7 are passageways 17; 19 are designed for one flow direction on different pitch circles. The design of the passage channels 17; 19 is only to be regarded as an example. An exit side of the passage channels 17; 19 is provided with at least one valve disk 21; 23 at least partially covered.

For example, a valve support 25 of the damping valve device 1 is fixed directly to the piston rod 9 . The valve carrier 25 has a circumferential annular groove 27, in which a variable-diameter valve element 29 is guided. This valve element 29 can move radially and forms a valve body for a throttle point 31 as part of the damping valve device 1 . The valve element 29 forms the throttle point 31 with an inner wall of the cylinder 11 , the inner wall representing a flow guide surface 33 .

The valve element 29 is fitted with a return spring 35, such as. e.g. B. in Fig. 2 is shown enlarged. There is a variable throttle cross section 39 between the flow guide surface 33 and an outer lateral surface 37 of the valve element 29, which generates an additional damping force.

At a piston rod speed in a first operating range, e.g. B. less than 1 m / s, the throttle point 31 is fully open. The damping force is then only from the passage channels 17; 19 in connection with the valve discs 21; 23 generated. When the valve disks 21; 23 lift the valve discs 21; 23 from its valve seat surface 41; 43 off. The lifting movement is carried out by a supporting disc 45; 47 limited.

In a second operating range with a piston rod speed that is greater than the limit speed of the first operating range, i.e. greater than the 1 m/s specified as an example, the valve element 29 changes to a throttle position and performs a closing movement in the direction of the flow guide surface 33. Due to the high flow rate of the damping medium in the throttle point 31 formed as an annular gap, a negative pressure is formed, which leads to a radial expansion of the valve element 29 . However, so that a blockage of the throttle point 31 can never occur, the defined minimum flow cross section z. B. are maintained by the return spring 35. In the present embodiment, the valve carrier 25 has a stop 49 on a cover disk 51 for this purpose; 53 of the valve carrier 25.

FIG. 2 shows a detailed representation of the damping valve device 1 according to FIG. 59 of the cover disks 51 ; 53 and an annular groove base 61 forms a pressure chamber 63, which has at least one Inflow opening 65 and an outflow opening 67 is connected to the working space of the vibration damper 3 . For example, between the two cover disks 51 ; 53 braced an intermediate ring 69, the valve carrier 25 can also be produced from solid material. The pressure chamber 63 causes a force component which is directed radially outward and widens the valve element 29 and which supports the negative pressure situation prevailing in the throttle point 37 . The function designations inflow opening and outflow opening are to be swapped over in the case of an opposite flow of the damping valve device.

3 to 5 show the valve element 29 as an individual component, which has at least two legs 71; 73 includes, which are movably mounted about a pivot bearing 75. The mobility of the legs 71 ; 73 enables the radial expansion movement, as described in connection with FIG.

The rotary bearing 75 is designed independently of the valve carrier 25 guiding the valve element 29, i. H. there is no axle element penetrating the pivot bearing 75 and the valve carrier 25 . If the valve carrier 25 does not have a stop 49, the valve element 29 can be expanded according to the diameter of the intermediate ring and inserted radially into the annular groove 27.

The leg 73 has a first bearing point 77 and the other leg 71 has a second bearing point 79, these two bearing parts 77; 79 form the pivot bearing 75 . The bearing point 77 of the leg 73 is formed by a radially slotted through-opening 80 with a lateral surface that is at least partially curved in the pivoting direction of the rotary bearing 75 . The lateral surface serves as a guide surface 81 for the bearing point 79 of the other leg 71 . The extension 85 has a curved guide surface 87 which cooperates with the guide surface 81 of the other leg 73 . In the area of the guide surface 87, the slot 83 has a circumferential angle of less than 180°. The extension 85 has a circular end at the end, but at least a segment 90 with the curved guide surface 87, the circumferential angle of which is greater than the circumferential angle of the slot 83 plus the pivoting angle of the two legs 71 ; 73. As a result, the two legs 71; 73 locked together via the pivot bearing 75 in the radial direction.

In Fig. 2, the valve carrier 25 has the stop 49 in the area of the cover plate 53. However, it can also be provided that a side wall of the slot 83 in the leg 73 forms a stop surface 89, which limits the pivoting angle, for the other leg 71, as shown in Figs 5 shows.

The minimum diameter of the valve element 29 is present when opposite end faces 91; 93 the leg 71; 73 are in contact, which also form a stop according to Figures 3 and 4.

As can be seen in the top views of the valve element according to FIGS. 4 and 5, the extension 85, starting from the segment 90 at the end, does not extend on a constant pitch circle diameter, but is flared slightly radially outward. As already described, the annular restoring spring 35 is supported on both legs 71; 73 off. For this purpose, the valve element 29 has a support contour 95 on one of the cover sides. At least the extension 85 of the leg 71 is aligned with the return spring 35 without overlapping. In FIG. 3, the pivot axis of the pivot bearing 75 is shown for clarification, which is designed to be clearly offset radially with respect to a receiving groove 97 for the return spring 35.

At a corresponding flow speed within the throttle point 31, the valve element 29 moves within the valve carrier 25, in that the two legs 71; Pivot 73 about the pivot bearing 75 until a stop position is reached. The stop position can be determined by a stop 89 on the valve carrier 25 or between the two legs, in particular in the area of the pivot bearing 75 . The extension 85 and the stop surface 89 of the slot 83 are then used for this.

FIGS. 6 and 7 show a valve element 29 with an additional function, in that the pivot bearing 75 has an elastic stop element 99 . The stop element can be formed by the extension 85 of the leg 71, for example. You can e.g. B. provide that the extension 85 has an elastic coating.

Alternatively, the extension 85 can have at least one elastic partial section 101, so that the extension 85 can be elastically deformed in the pivoting direction, as is shown in FIG. The extension 85 has a thickening 105, z. B. at the opposite end of the segment 90 within the leg 71 . As a result, the extension 85 cannot become detached from the leg 71 . The extension 85 can, for. B. also consist entirely of an elastomeric material.

Optionally, the valve element 29 can be designed in such a way that the stop face 89 of one leg 73 and the elastic extension 85 of the other leg 71 form a second pivot bearing 103 . This shifts the axis of rotation of the legs 71; 73 within the valve element 29 with the effect that the throttle cross section 39 of the throttle point 31 can be adjusted even more precisely to a desired cross section. Furthermore, with this elastic stop function, a counterforce to the compressive force within the pressure chamber 63 can be achieved, so that a linear increase in compressive force leads to a degressive expansion behavior of the valve element 29 .

In the embodiment according to FIG. 7, the operating principle corresponding to FIG. 6 is adopted, but the stop element 99 is formed by an elastic insert of the rotary bearing 75. The radially pronounced thickening 105 on the insert also prevents the elastic insert from being pulled out of the leg 73 .

The design of the damping valve device according to FIG. 8 is based on FIG. 4. The main difference from the variants described above is that the two legs 71; 73 have an axial overlap 119 in the area of the pivot bearing 75 (FIG. 9). In a first plane 107 of the rotary bearing 75, a first joint section with the extension 85 is made in the through-opening 80. This component of the pivot bearing 75 corresponds to the structure of Figures 2 to 7. In addition, pivot bearing 75 has a second joint section of pivot bearing 75 in a second plane 109 with a convexly curved end face 111 of leg 71 and with a complementary concavely curved end face 113 of the other leg 73. Both pivot bearing sections preferably have a common axis of rotation 115.

The extension 85 of the first articulation section is made on a cover face 117, which is part of the axial overlap 119 between the two legs 71; 73 is. Consequently, the slit 83 in the leg 73 is covered in the axial direction. Another advantage of this design is that the curved end faces 111; 113 take over the bearing guidance and the extension 85 within the through-opening 80 only serves to radially secure the two legs 71; 73 against falling apart during assembly is used. Consequently, the extension 85 does not need to be completely rounded within the through opening 80. A simple cross bar which is wider than the slot 83 is sufficient for the desired security function.

During assembly, a simple axial insertion movement of the extension 85 into the through-opening 80 is sufficient. This is already the radial falling apart of the legs 71; 73 prevented. The return spring 35 finally ensures the defined initial seat of the valve element 29 within the annular groove 27.

Figures 10 and 11 show a variant of the valve element 29, in which between the two legs 71; 73 a separate joint element 121 is arranged, which is part of both the first and the second pivot bearing 75: 103. Both pivot bearings 75; 103 are supported by a concave end face 113 on the legs 71; 73 and convex end faces 111 on the separate joint element 121 are formed. Likewise, between the joint element 121 and the two legs 71; 73 an axial overlap 119, so that the two legs 71; 73 rest axially on the separate joint element 121 . The principle of securing against loss via the connection between a respective extension 85 and a through-opening 80 with a radial slot 83 applies to both legs 71; 73 realized. That's why they can legs 71; 73 perform a rotational movement towards one another, but cannot be detached radially from one another.

A functional difference between the versions according to FIGS. 10 and 11 and the variants according to FIGS. 2-9 is that the two legs 71; 73 can not only perform a pivoting movement to each other, but that by the two pivot bearings 75; 103 a limited radial displacement of the two legs 71; 73 to each other is possible.

In the embodiment according to FIG. 10, the radial displaceability between the legs 71; 73 is significantly larger than in the valve element 29 according to FIG. 11, which has a significantly greater distance between the two pivot bearings 75; 103 and additionally has a peripheral area with an outer lateral surface 37 . The separate joint element 121 practically forms a further leg, which also extends radially to the two legs 71; 73 can move.

reference sign

damping valve device

Vibration damper first damping valve

dampening valve body

piston rod

Cylinder working space on the piston rod side working space away from the piston rod passage channels

passage channels

valve disc

valve carrier

ring groove

Valve element A Leg of the valve element

Leg of the valve element

throttle point

flow control surface

return spring outer surface of the valve element

Throttle cross-section of the throttling point

valve seat surface

support washer

attack

cover disk

Shield inner surface of the valve element

ring groove side face

ring groove side face Ring groove base area pressure chamber inflow opening outflow opening intermediate ring leg leg pivot bearing first bearing point second bearing point passage opening guide surface slot extension

Guide surface (extension) Stop surface Segment Front surface Front surface Supporting contour Receiving groove Stop element Elastic section Second rotary bearing Thickening First level Second level Front surface convex Front surface concave Axis of rotation Cover side Axial overlap Joint element

Claims

patent claims

1. Damping valve device (1) for a vibration damper (3), comprising a variable-diameter valve element (29) which is held by a valve carrier (25) and depending on a flow rate of a damping medium within a throttle point (31) starting from a passage position by a radial closing movement in the direction of a flow guide surface (33) assumes a throttling position, the valve element (29) comprising at least two legs (71; 73) which are movably mounted about a pivot bearing (75) which is independent of the valve element ( 29) leading valve support (25), the leg (73) having a first bearing point (77) and the other leg (71) having a second bearing point (79) and these two bearing points (77; 79) the rotary bearing (75) form, characterized in that the bearing point (77) of one leg (73) of a radially slotted through-opening with an at least partially in Schwenkrichtun g of the rotary bearing (75), the lateral surface being a guide surface (81) for the bearing point (79) of the other leg (71), with an extension running in the circumferential direction via a slot (83) of the bearing point (77). (85) of the other leg (71) engages in the bearing point (77) and the extension (85) has a curved guide surface (87) which interacts with the guide surface (81) of the other leg (73), the slot (83 ) in the area of the guide surface (87) has a circumferential angle of less than 180°.

2. Damping valve device according to claim 1, characterized in that a side wall of the slot (83) forms a stop surface (89) for the other leg (71).

3. Damping valve device according to claims 1 or 2, characterized in that opposite end faces (91; 93) of the legs (71; 73) form a stop for a minimum diameter of the valve element (29).

4. Damping valve device according to at least one of claims 1 to 3, characterized in that the two legs (71; 73) by an annular restoring spring (35) on a support contour (95) on the common top side of the Legs (71; 73) are prestressed in the direction of the minimum diameter of the valve element (29), at least the extension (85) of the leg (71) being aligned with the restoring spring (35) without overlapping.

5. damping valve device according to at least one of claims 1 to 4, characterized in that the pivot bearing (75) has an elastic stop element (99).

6. Damping valve device according to claim 5, characterized in that the stop element (99) is formed by an elastic insert of the pivot bearing (75).

7. Damping valve device according to claim 6, characterized in that the stop element (99) is formed by the extension (85) of the leg (71).

8. Damping valve device according to claim 7, characterized in that the extension (85) has at least one elastic section (101), so that the extension (85) is elastically deformable in the pivoting direction.

9. Damping valve device according to claim 5, characterized in that a stop contour (89) of one leg (73) and the elastic extension (85) of the other leg (71) form a second pivot bearing (103).

10. Damping valve device according to at least one of claims 1 to 9, characterized in that the two legs (71; 73) have an axial overlap (119) in the region of the pivot bearing (75), wherein in a first plane (107) of the pivot bearing ( 75) a first joint section with the extension (89) in the through opening (80) and in a second plane (109) a convexly curved end face (111) of one leg (71) with a complementary concavely curved end face (113) of the other leg (73) are executed.

11. Damping valve device according to at least one of claims 1 to 10, characterized in that a separate joint element (121) within the Ventileie- merits (29) has at both ends a pivot bearing (75; 103) with an extension (85) which engages in the through-opening (80) of the adjacent leg (71; 73).

12. Damping valve device according to claim 11, characterized in that the separate joint element (121) forms part of the outer lateral surface (37) of the valve element (29).

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