Adjustable damping valve device for shock absorber

Abstract

The invention relates to an adjustable damping valve arrangement for a shock absorber, comprising a damping valve housing in which a pilot valve for hydraulically controlling a main stage valve is arranged, said damping valve housing being hydraulically connected to a working chamber on the piston rod side of a working cylinder of the shock absorber and to a working chamber remote from the piston rod, wherein the damping valve device has at least four check valves for rectifying the control volume flow of the pilot valve, the check valves each releasing the control volume flow from one of the working chambers to the pilot valve and the check valves each releasing the control volume flow from the pilot valve to one of the two working chambers, the damping valve housing comprises a valve housing ring having a channel system for the outflow of the control volume flow from the pilot valve to at least one of the two working chambers, the two check valves switched to the outflow of the control volume flow having a common check valve ring as a stationary valve body, said check valve ring being separate from the valve housing ring.

Description

Technical Field

[0001] The invention relates to an adjustable damping valve arrangement for a shock absorber according to the preamble of patent claim 1 . Background Art

[0002] Document DE 44 18 972 A1 relates to an adjustable damping valve arrangement comprising a valve housing located on the piston rod of a shock absorber. The functional advantage of this damping valve arrangement lies in the fact that a single pilot valve is used to actuate the main stage valve when fluid flows in from both the working chamber on the piston rod side and the working chamber remote from the piston rod.

[0003] To this end, the damping valve arrangement has a total of four non-return valves, which serve to rectify the volume flow from the piston rod-side working chamber and the working chamber remote from the piston rod to the pilot valve, and to discharge fluid from the return flow chamber of the pilot valve to both working chambers. The non-return valves that switch to inflow are located on or within the main stage valve body.

[0004] The check valves that switch the flow out of the return chamber are each arranged on the end face of the valve housing ring. Within the valve housing ring, the mainstage valve body slides in a tubular valve housing, which also forms the longitudinal section for the return flow of the electromagnetic actuator. This results in an overall complex valve design, which was abandoned according to DE 198 22 448 A1 in favor of a simpler damping valve arrangement, which only performs a pilot valve function when the flow originates from the working chamber on the piston rod side. Summary of the Invention

[0005] The object of the present invention is to provide a damping valve arrangement having a pilot valve which is effective for both operating directions of the shock absorber, wherein the structural design of the damping valve arrangement is simplified compared to the prior art.

[0006] This object is achieved in that the two check valves switched to control the outflow of the volume flow have a common check valve ring as a stationary valve body, which is independent of the valve housing ring.

[0007] The check valve ring simplifies the assembly boundaries, thereby enabling a simpler and more robust design of the key components of the damping valve device. Furthermore, the two check valves that control the outflow of the volume flow can be arranged close to the pilot valve, so that the damping medium encounters only a small throttling resistance before reaching the two check valves.

[0008] In another advantageous embodiment, the check valve ring is axially supported on the valve housing ring. On the valve housing ring.

[0009] According to advantageous dependent claims, the non-return valve ring is centered relative to the valve housing ring.

[0010] For simple flow guidance of the damping medium from the pilot valve, the non-return valve ring has an annular groove which in turn has a connection opening to the channel system in the valve housing ring.

[0011] In addition, the check valve ring has an annular interface channel leading to the return flow chamber of the pilot valve. During assembly, there is no need to pay attention to the position orientation of the assembly of the check valve ring in the circumferential direction.

[0012] As a further measure for simple flow guidance, the connecting channel is connected to the annular groove via at least one radial channel. Due to the open channel guidance in the non-return valve ring, the non-return valve ring can be designed very simply as a sintered component.

[0013] In order to ensure a simple design of the non-return valve, the non-return valve ring is equipped on both sides with at least one non-return valve disk.

[0014] Preferably, at least one non-return valve disk is centered relative to the valve housing ring. This allows the non-return valve disk to have a larger cross-section than if the non-return valve disk were centered relative to the non-return valve ring. Furthermore, the geometry of the non-return valve ring is simplified, as no centering area is required.

[0015] Preferably, the non-return valve ring comprises a cover ring, by which the non-return valve ring is axially fixed in the damping valve housing. This allows the internal geometry of the damping valve housing to be kept simple.

[0016] The cover ring also serves for the flow guidance, wherein the cover ring has at least one connecting channel for forming a connection between the return flow chamber of the pilot valve and a connecting channel in the non-return valve ring.

[0017] Like the check valve body, the cover ring is also centered relative to the valve housing ring.

[0018] In order to prevent misalignment of the components forming the non-return valve, the valve housing ring has a centering projection at least for the non-return valve ring, with which the cover ring and the non-return valve disk can also be centered.

[0019] Compared to the prior art, the simplified valve housing ring offers the possibility of forming the housing of the main stage valve with the valve housing ring, wherein the main stage valve body is guided in a sealed and axially displaceable manner within the valve housing ring. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be described in more detail with reference to the following drawings.

[0021] in:

[0022] Figure 1 and Figure 2A cross section of a damping valve arrangement is shown;

[0023] Figure 3 Shown Figure 1 Detailed view of the main stage valve body;

[0024] Figure 4 Shown Figure 1 and Figure 2 The check valve ring as an independent component;

[0025] Figure 5 Shown Figure 1 and Figure 2 The check valve disc as an independent component;

[0026] Figure 6 Shown Figure 1 and Figure 2 Detailed view of the check valve assembly; and

[0027] Figure 7 and Figure 8 Shown Figure 6 The cover ring is a separate component. DETAILED DESCRIPTION

[0028] Figure 1 and Figure 2 The figures show cross-sections of an adjustable damping valve arrangement 1 for a shock absorber 3 in different planes. In this exemplary embodiment, the damping valve arrangement 1 is shown located in a damping valve housing 5 on an axially displaceable piston rod 7 in a working cylinder 9 of the shock absorber 1. However, the damping valve housing 5 and therefore the damping valve arrangement 1 can also be arranged spatially outside the shock absorber 1 and hydraulically connected, for example, via a line connection or a hose connection.

[0029] The damping valve arrangement 1 comprises an electromagnetic actuator 11 having a solenoid coil 13 and an armature 15 , which acts on the front side on a pilot valve body 17 of a pilot valve 19 . The force of the solenoid coil 13 acts in opposition to at least one return spring 21 .

[0030] The pilot valve 19 serves for hydraulically controlling a main stage valve 23 , via which a working chamber 25 on the piston rod side and a working chamber 27 remote from the piston rod are connected to one another in the working cylinder 9 . Figure 1The radial connecting channel 29 in the valve housing ring 31, a component of the damping valve housing 5, is shown. This connecting channel connects the piston rod-side working chamber 25 to the main stage valve 23. Passive damping valves 33 and 35 are arranged between the working chamber 27 remote from the piston rod and the main stage valve 23 for each flow direction of the damping valve arrangement 1. Both passive damping valves 33 and 35 are selectively operable. Regardless of the working direction of the piston rod 7 in the shock absorber 3, the damping force-determining volume flow of the damping medium in the working cylinder 9 is discharged via the connecting channel 29, the main stage valve 23, and the two passive damping valves 33 and 35. Furthermore, a sealing piston 36, as a functional section of the damping valve housing 5, ensures the spatial separation of the two working chambers 25 and 27.

[0031] The main stage valve 23 includes a main stage valve body 37 and a main stage valve seat surface 39 (see Figure 3 ), the main-stage valve seat surface is formed by the valve ring 41 within the valve housing ring 31. Functionally, the main-stage valve body 37 consists of two parts. The first functional section forms the closing body 37A, which, together with the main-stage valve seat surface 39, determines the throttling cross section of the main-stage valve 23. The second functional section is formed by the separating piston 37B, which is firmly connected to the closing body 37A and thus performs a synchronous displacement movement. The main-stage valve body 37 is guided axially displaceably within the stepped opening 43 of the valve housing ring 31. The separating piston 37B seals against the inner circumferential surface 43A of the stepped opening 43. The separating piston 37B, a portion of the circumferential surface 43A, and the bottom 43B of the stepped opening 43 form a first control chamber 45. This first control chamber 45 is connected to the radial connection channel 29 via at least one first throttling channel 47. Due to the throttling function of the throttling channel 47, a pressure drop occurs between the pressure in the connection channel 29 and the pressure in the first control chamber 45.

[0032] The separating piston 37B has a valve pin 49 pointing toward the pilot valve 19 and having a pilot valve seat surface 51 for the pilot valve body 17 at its end. The valve pin 49 is hollow and has at least one radial connection opening 53 leading to an axial channel 55 as part of the first control chamber 45. This first control chamber has a second throttle channel 59 in the intermediate wall 57 in the flow direction to the pilot valve 19. A second control chamber 61 associated with the main stage valve body extends between the intermediate wall 57 and the pilot valve 19. The radial connection opening can be designed as a throttle valve, so that a pressure difference can be established between the first control chamber and the second control chamber of the main stage valve body 37.

[0033] At least one axial channel 63 extends within the closing body 37A of the mainstage valve body 37. This axial channel, which, if necessary, has a throttling function similar to the first throttle channel 47, connects a connecting chamber 65 of the damping valve arrangement 1 with the first control chamber 45 and with the second control chamber 61. The at least one axial channel 63 opens into the axial channel 55 of the valve pin 49. Both the first throttle channel 47 and the axial channel 63 between the connecting chamber 65 and the first control chamber 45 are equipped with non-return valves 67, 69, which open in the direction of inflow into the first control chamber 45. This prevents a hydraulic short-circuit of the pilot valve 19 via the first control chamber 45.

[0034] The lifting distance of the pilot valve body 17 from the pilot valve seat surface 51 determines the throttle cross section, which in turn determines the pressure levels in the first control chamber 45 and the second control chamber 61. The pressures in the two control chambers 45 and 61 multiplied by the axial pressure-bearing area on the separating piston 37B yield the effective closing force acting on the main stage valve body 37. Given a predetermined operating motion of the shock absorber 3, this effective closing force determines the damping force of the shock absorber 3.

[0035] The damping medium passing through the pilot valve 19 reaches the return chamber 71 of the pilot valve between the bottom of the valve housing ring 31 and the actuator 11, which is connected to a non-return valve assembly 73, which comprises a non-return valve ring 75, which is equipped with at least one non-return valve disk 77 on both sides; 79 ( Figure 5 ). The check valve ring 75 is a replaceable component that is independent of the valve housing ring 31. The check valve discs 77; 79 on both sides are combined with the check valve ring 75 to form two check valves 81; 83 to control the control volume flow flowing out of the pilot valve 19 to the two working chambers 25; 27 of the working cylinder 9. Along the flow direction from the check valve assembly 73 to the working chamber 25 on the piston rod side, the damping valve housing 5 has at least one connecting opening 85 that is radial in this example. In order to connect the pilot valve 19 to the working chamber 27 away from the piston rod, the valve housing ring 31 has a channel system 87 leading to the interface chamber 65. When the fluid flows from one of the two working chambers 25; 27 into the check valve assembly 73, the check valve 81; 83 that is directly flowed through, that is, bypassing the pilot valve 19, is closed.

[0036] The check valve ring 75 is centered on the valve housing ring 31 via its central through-opening 89. Figure 4As shown, the non-return valve ring 75 has an annular groove 91 pointing toward the return chamber 71 and including an axial connection opening 93 leading to the channel system 87 in the valve housing ring 31. The annular groove 91 is radially delimited by two annular support surfaces 95 and 97 for the non-return valve disk 77. The inner support surface 97 is interrupted by at least one radial channel 99, which connects the annular groove 91 to a radially inner connection channel 101. The connection channel 101 is directly connected to the return chamber 71 of the pilot valve 19.

[0037] Furthermore, the two non-return valve disks 77; 79 are preferably centered on the valve housing ring 31. In principle, it is also conceivable that at least one valve disk 77; 79 is centered on the non-return valve ring 75. The non-return valve disk 77; 79 preferably has a Figure 5 The basic design shown has an inner centering web 103 which allows an unimpeded flow of damping medium from the return chamber 71 into the connecting channel 101 .

[0038] The lifting movement of the non-return valve disk 79 for the channel system 87 in the valve housing ring 31 is limited by the valve housing ring 31. For the lifting movement of the non-return valve disk 77 on the upper side of the non-return valve ring 75, a cover ring 103 is used, which also fixes the non-return valve ring 75 axially in the damping valve housing 5. Figure 7 、 Figure 8 The cover ring 103 is shown as a separate component. It also has at least one connecting channel 107 at a central through-opening 105, which serves to connect the return flow chamber 71 of the pilot valve 19 to the connection channel 101 in the non-return valve ring 75. The cover ring 103 is also centered on the valve housing ring 31. For this purpose, the valve housing ring has a central centering projection 109, relative to which the non-return valve ring 75 and the non-return valve disk 77 are also centered. The support surface 111 of the cover ring 103 serves to limit the lifting movement of the non-return valve disk 77.

[0039] When fluid flows into the damping valve arrangement 1 due to compression in the working chamber 27 remote from the piston rod, the damping medium flows through the passive damping valve 35 and ensures that the mainstage valve body 37 is pressurized within the pressure-bearing surface defined by the mainstage valve seat surface 39 in the connecting chamber 65. The control volume flows via the axial channel 63 and the open check valve 69 to the first control chamber 45 and further via the connecting opening 53 to the second control chamber 61. The pressure in both control chambers 45 and 61 exerts a hydraulic closing force on the mainstage valve body 37. The control volume flows via the pilot valve 19 and the check valve disk 77, which is lifted from the check valve ring 75, and through the connecting opening 85 into the working chamber 25 on the piston rod side.

[0040] Damping medium acting on the non-return valve 83 via the channel system 87 in the valve housing ring 31 closes the non-return valve 83. Under this inflow of the damping valve arrangement 1, the non-return valve 67 in the separating piston 37B of the main stage valve body 37 is also closed.

[0041] When fluid begins to flow from the piston-rod-side working chamber 25 toward the damping valve arrangement 1, the displaced damping medium is applied to the annular surface of the main-stage valve body 37, which extends radially outside the main-stage valve seat surface 39 of the main-stage valve 23 and within the circumferential surface 43A of the valve housing ring 31. This pressure also creates a lifting force on the main-stage valve body. Simultaneously, the first control chamber 45 is hydraulically pressurized in parallel via the first throttle channel 47, which also generates a pressure increase in the second control chamber 61. This pressure increase, together with the pressure increase in the first control chamber 45, creates a closing force on the main-stage valve body 37. The control volume flow flowing into the return chamber 71 via the pilot valve 19 then also reaches the connection channel 101, enters the annular groove 91 via at least one radial channel 99, and can then flow through the connection opening 93 connected to the channel system 87 into the connection chamber 65. From there, it can flow through the passive damping valve 33 into the working chamber 27 distal to the piston rod. Here, the check valve 81 pointing toward the piston rod-side working chamber 25 is also closed by the reverse flow from the piston rod-side working chamber 25 , so that the control volume flow is rectified by the pilot valve 19 by using a total of four check valves 67 ; 69 ; 81 ; 83 .

[0042] List of reference numerals:

[0043] 1 Adjustable damping valve device

[0044] 3 shock absorbers

[0045] 5 Damping valve housing

[0046] 7 Piston rod

[0047] 9 working cylinders

[0048] 11 Actuator

[0049] 13 Excitation coil

[0050] 15 Armature

[0051] 17 Pilot valve body

[0052] 19 Pilot valve

[0053] 21 Return spring

[0054] 23 Main stage valve

[0055] 25 Working chamber on the piston rod side

[0056] 27 Working chamber away from the piston rod

[0057] 29 radial interface channels

[0058] 31 Valve housing ring

[0059] 33 Passive Damping Valve

[0060] 35 Passive Damping Valve

[0061] 37 Main stage valve body

[0062] 37A Main stage valve body closure

[0063] 37B Main stage valve body release piston

[0064] 39 Main stage valve seat surface

[0065] 41 valve ring

[0066] 43 Stepped opening of valve housing ring

[0067] 43A Side surface of stepped opening

[0068] 43B stepped opening bottom

[0069] 45 First control chamber

[0070] 47 First throttle channel

[0071] 49 valve pin

[0072] 51 Pilot valve seat surface

[0073] 53 interface opening

[0074] 55 Axial channel

[0075] 57 Middle wall

[0076] 59 Second throttle channel

[0077] 61 Second control chamber

[0078] 63 Axial channel

[0079] 65 Interface chamber

[0080] 67 Check valve

[0081] 69 Check valve

[0082] 71 Reflow Chamber

[0083] 73 Check valve assembly

[0084] 75 Check valve ring

[0085] 77 Check valve disc

[0086] 79 Check valve disc

[0087] 81 Check valve

[0088] 83 Check valve

[0089] 85 connection opening

[0090] 87-channel system

[0091] 89 through opening

[0092] 91 Annular groove

[0093] 93 interface opening

[0094] 95 support surface

[0095] 97 Support surface

[0096] 99 radial channels

[0097] 101 interface channel

[0098] 103 Cover Ring

[0099] 105 through opening

[0100] 107 Axial connecting channel

[0101] 109 Centering protrusion

[0102] 111Support surface.

Claims

1. An adjustable damping valve arrangement (1) for a shock absorber (3), comprising a damping valve housing (5), in which a pilot valve (19) for hydraulically controlling a main stage valve (23) is arranged, wherein: The damping valve housing (5) is hydraulically connected to a working chamber (25) on the piston rod side and a working chamber (27) remote from the piston rod of a working cylinder (9) of the shock absorber (3), wherein the damping valve device (1) has at least four non-return valves (67; 69; 81; 83) for rectifying the control volume flow of the pilot valve (19), wherein the non-return valves (67; 69) respectively release the control volume flow from one of the working chambers (25; 27) to the pilot valve (19), and the non-return valves (81; 83) A control volume flow is released from the pilot valve (19) to one of the two working chambers (25; 27), respectively, wherein the damping valve housing (5) includes a valve housing ring (31), which has a channel system (87) for allowing the control volume flow to flow out of the pilot valve (19) to one of the two working chambers (25; 27), characterized in that the two check valves (81; 83) switched to control volume flow outflow have a common check valve ring (75) independent of the valve housing ring (31) as a fixed valve body.

2. The adjustable damping valve device (1) according to claim 1, characterized in that: The check valve ring (75) is axially supported on the valve housing ring (31).

3. The adjustable damping valve device (1) according to claim 1 or 2, characterized in that: The non-return valve ring (75) is centered relative to the valve housing ring (31).

4. The adjustable damping valve arrangement (1) according to at least one of claims 1 to 3, characterized in that The non-return valve ring (75) has an annular groove (91) with a connection opening (93) to the channel system (87) in the valve housing ring (31).

5. The adjustable damping valve arrangement (1) according to at least one of claims 1 to 4, characterized in that The check valve ring (75) has an annular connection channel (101) leading to the return flow chamber (71) of the pilot valve (19).

6. The adjustable damping valve device (1) according to claim 5, characterized in that: The interface channel (101) is connected to the annular groove (91) via at least one radial channel (99).

7. The adjustable damping valve arrangement (1) according to at least one of claims 1 to 6, characterized in that The non-return valve ring (75) is equipped on both sides with at least one non-return valve disk (77; 79).

8. The adjustable damping valve device (1) according to claim 7, characterized in that: The at least one non-return valve disk (77; 79) is centered relative to the valve housing ring (31).

9. The adjustable damping valve arrangement (1) according to at least one of claims 1 to 8, characterized in that The check valve ring (75) comprises a cover ring (103), and the check valve ring (75) is axially fixed in the damping valve housing (5) by the cover ring.

10. The adjustable damping valve device (1) according to claim 9, characterized in that: The cover ring (103) has at least one connecting channel (107) for forming a connection between the return chamber (71) of the pilot valve (19) and the interface channel (101) in the check valve ring (75).

11. The adjustable damping valve device (1) according to claim 9 or 10, characterized in that: The cover ring (103) is centered relative to the valve housing ring (31).

12. The adjustable damping valve arrangement (1) according to at least one of claims 1 to 11, characterized in that The valve housing ring (31) has a centering projection (109) at least for the non-return valve ring (75).

13. The adjustable damping valve arrangement (1) according to at least one of claims 1 to 12, characterized in that The valve housing ring (31) forms the housing of the main stage valve (23), wherein the main stage valve body (37) is guided in the valve housing ring (31) in a sealed and axially displaceable manner.

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