Adjustable damping valve device

Abstract

Adjustable damping valve device (3; 5), comprising a main stage valve (61) with a main stage valve body (59) whose closing force is adjustable on a valve seat surface (65), wherein the valve seat surface (65) is formed by a hydraulically fixed pre-valve (69) which has damping channels and at least one valve disc (67), and is arranged spatially and hydraulically in series with a main stage valve (61), characterized in that the valve seat surface (65) of the main stage valve (61) is formed by the elastic valve disc (67) of the pre-valve (69).

Description

[0001] The invention relates to an adjustable damping valve device according to the preamble of claim 1.

[0002] From DE 10 2015 200 348 A1, an adjustable damping valve assembly is known which, in addition to a main stage valve, also has a fixed pilot valve. The pilot valve, with its damping channels and valve discs, is part of a valve ring that forms a valve seat surface of the main stage valve. Functionally, the pilot valve and the main stage valve form a hydraulic series connection.

[0003] The valve ring is a comparatively complex component which, in addition to the sub-functions already described, also serves to fix a housing insert of the main stage valve.

[0004] DE 10 2014 224 021 A1 describes a damping valve device with a similar hydraulic design. The design difference lies in the fact that a main stage valve body is supported on a valve element of the upstream valve. The valve element is formed by a rigid control ring that rests on a flat surface of the upstream valve and, when flow originates from a lower working chamber, lifts off this flat surface, thereby opening pressure ports of the upstream valve.

[0005] DE 10 2012 210 685 A1 also relates to an adjustable damping valve device. In this design, the main stage valve body is supported on a housing insert via a valve disc. The valve disc is fixedly connected to the main stage valve body and has a recess at its edge, which forms a pre-opening cross-section that is thus hydraulically parallel to the main stage valve.

[0006] Within the annular valve seat of a pull valve, a constant pre-opening cross-section is provided, which is permanently open regardless of the switching state of the main stage valve. This pre-opening cross-section thus also influences a damping force characteristic at maximum closing force of an actuator on the main stage valve body.

[0007] This valve design requires a very precisely machined flat surface and precise manufacturing of the control ring, especially the valve bridges and contact surfaces. Otherwise, undefined leakage will occur within the damping valve assembly.

[0008] The object of the present invention is to realize a damping valve device with a pre-valve in which the manufacturing effort is reduced compared to the prior art.

[0009] The problem is solved by having the valve seat surface of the main stage valve be formed by an elastic valve disc of the pilot valve.

[0010] This solution offers several advantages. Firstly, it features a very compact axial design. Secondly, the valve disc provides a highly precise yet easily manufactured component for the valve seat. Previous grinding or other calibration steps are no longer necessary. Additionally, the elastic valve disc prevents a clunking noise during the closing movement of the main stage valve.

[0011] According to a further advantageous embodiment, a flow connection to the main stage valve is hydraulically connected in parallel to a flow path to the upstream valve. This eliminates any dependencies, for example, regarding the volume flows between the two valves, which would otherwise need to be considered when dimensioning at least one of the valves.

[0012] Another significant advantage is that a flow path with a pre-opening cross-section of the flow connection to the main stage valve is hydraulically connected in parallel. This allows the main stage valve to effectively block the flow of the damping medium in its closed position. It is not mandatory but is available as an option.

[0013] According to an advantageous dependent claim, the effective size of the pre-opening cross-section is adjustable via at least one valve disc of the pre-valve. With an adjustable pre-opening cross-section, the response behavior of the vibration damper to excitation can be set separately from the damping force behavior to faster excitations.

[0014] Because the valve disc for the main stage valve determines the pre-opening cross-section, the pre-opening cross-section can be adjusted continuously and with a single adjustment mechanism, especially when the valve disc is adjusted via the closing force on the main stage valve body.

[0015] Furthermore, it is provided that a valve disc of the pre-valve has a stop surface for the valve disc that determines the pre-opening cross-section. This implements the entire function of the adjustable pre-opening cross-section within the pre-valve, allowing this function to be tested even before the damping valve assembly is installed.

[0016] To simplify the overall design of the pre-valve, the main stage valve body at least indirectly forms a stop for the lifting movement of the valve disc of the pre-valve.

[0017] Preferably, the closing force on the main stage valve is adjustable by means of a pre-stage valve that influences the pressure in a control chamber, wherein a pressurized area of ​​the control chamber is formed by the valve disc of the pre-stage valve. This simplifies the design complexity of the control chamber.

[0018] Optionally, the valve disc of the upstream valve, which forms the control chamber, can be force-transmittingly connected to a valve disc of the upstream valve, which determines the damping force of the upstream valve. Force-transmitting means that a deformation of the valve disc, acting as the valve seat surface of the main stage valve, is transferred to the valve disc of the upstream valve to achieve a closing force component for the upstream valve. Preferably, a spring element is used as the force transmission means, so that relative movement between the valve disc for the main stage valve and the original valve disc of the upstream valve is possible.

[0019] To make optimal use of the available installation space, the valve discs of the pilot valve are held by a bolt-shaped fastening element, which provides the flow connection to the main stage valve. Preferably, a hollow rivet is used as the fastening element, so that no machining of the fastening element for the flow connection is necessary.

[0020] According to an advantageous dependent claim, a section of the flow path of the pre-opening cross-section is formed by at least one valve disc, which is spatially arranged between the valve disc of the pre-valve and the valve disc for the main stage valve. The closing behavior in the flow path of the pre-opening cross-section can be adjusted by the number and diameter ratios of the valve discs.

[0021] Additionally, a section of the flow path of the upstream opening cross-section can be formed by a fastening element holding the valve discs of the upstream valve. This design of the flow path requires no modifications to the valve disc of the upstream valve.

[0022] Particularly when the valve disc of the upstream valve is subjected to only a low load, the pre-opening cross-section is formed by an opening in the valve disc of the upstream valve, whereby the valve disc interacts with at least one spacer disc to the valve disc of the main stage valve. The spacer disc is selected in its diameter dimensions such that the pre-opening cross-section is never blocked by the spacer disc.

[0023] The invention will be explained in more detail with reference to the following description of the figures.

[0024] It shows: Fig. 1 vibration damper with an adjustable damping valve device Fig. 2 Sectional view through the damping valve assembly according to Fig. 1 Fig. 3 Detailed view of the main stage valve according to Fig. 2 Fig. 4 - 6 valve discs of the main stage valve as individual parts Fig. 7 Closed pre-opening cross-section according to Fig. 2 Fig. 8 Alternative variant to the execution according to Fig. 2 - 7

[0025] The Fig. Figure 1 shows an adjustable vibration damper 1 with an adjustable damping valve assembly 3; 5 for each direction of movement of a piston 7 on a piston rod 9. Both adjustable damping valves 3; 5 are connected via a fluid connection 11; 13 to a working chamber 15; 17. In principle, however, the invention can also be used with a vibration damper with an adjustable damping valve for different directions of movement of the piston.

[0026] The piston 7 divides a cylinder 19, completely filled with damping medium, into a working chamber 15; 17 on the piston rod side and a working chamber 15; 17 on the remote side. A compensating chamber 21 serves to compensate for the volume of damping medium displaced by the piston rod 7. The compensating chamber 21 extends completely concentrically to the cylinder 19 and is radially bounded by an outer reservoir tube. The reservoir tube serves as a support for the two adjustable damping valves 3; 5.

[0027] In addition to the cylinder 19, the vibration damper 1 has an intermediate tube 23; 25, each connected to one of the working chambers 15; 17 and one of the adjustable damping valves 3; 5. For this purpose, a connection opening 27 is provided for the first intermediate tube 23 in the piston rod-side working chamber 15, which leads to the first fluid connection 11 and the first adjustable damping valve assembly 3. The working chamber 17 furthest from the piston rod also has such a connection opening 29 to the second fluid connection 13. The fluid connections 11; 13 are each formed by the intermediate tubes 23; 25 and the sections of the cylinder 19 enclosed by the intermediate tubes 23; 25. During a retraction movement, the damping medium displaced from the working space 17 farther from the piston rod is conveyed via the fluid connection 13 and via a connection opening 31 into the damping valve device and flows via at least one outlet opening 33 into the compensation chamber 21.For the extension movement, the fluid connection 13 with a connection opening 35 is available, so that the damping medium is supplied to the damping valve device 3, through which it also flows through the outlet opening into the compensation chamber 21.

[0028] In the Fig. Figure 2 shows the adjustable damping valve assembly 3 as a separate unit. An actuator 41, in the form of an electromagnetic drive, is arranged in a damping valve housing 39. The actuator 41 has a solenoid coil 43, which exerts an actuating force on an axially movable valve armature 45 in conjunction with a valve body 47 that is movable relative to it. A spring arrangement 49 on both sides of the valve armature 45 biases the valve armature 45 into a predetermined position relative to an axially fixed, cup-shaped housing insert 51. Depending on the predetermined position, the valve body 47 can engage in a drain opening 53 of the housing insert or, independently of any energization of the solenoid coil 43, rest under bias on a valve seat surface 55. The valve body 47 and the drain opening 53 form a pre-stage valve 57.

[0029] An axially movable main stage valve body 59 of a main stage valve 61 is mounted in the housing insert 51. A hydraulic closing force on the main stage valve 61 is adjustable via the hydraulic pressure within a control chamber 63. This adjustable closing force ensures that the main stage valve body 59 rests against a valve seat surface 65. The valve seat surface 65 is formed by an elastic valve disc 67 of a pre-valve 63, which is spatially arranged in series with a main stage valve 61. Fig. 3) A pressurized area of ​​the control chamber 63 is formed by the valve disc 67 of the pre-valve 69. The control chamber 63 thus extends axially between the valve disc 67 and the inside of the housing insert 51. In the main stage valve body 59, there is a connecting opening 71 between an interior space 73 of the main stage valve body 59 and an intermediate space 75 between the housing insert 51 and a rear side of the main stage valve body 59. The hydraulically effective cross-section of the intermediate space 75 is larger than the cross-section of the interior space 73. Therefore, a resultant closing force always acts on the main stage valve body 59.

[0030] The pre-valve 69 has a valve ring 77 with a connecting nozzle 79 that projects into the fluid connection 11; 13 of the respective intermediate pipe. The valve ring 77 has a spoke profile 81 with a central hub in which a bolt-shaped fastening element 83 is arranged. The fastening element 81 secures all valve discs of the pre-valve to the valve ring 77. (see Fig. 3) Between the spokes lies a flow path 85 extending from the connecting nozzle 79 to a valve seat surface 87 of the valve ring 77. At least one valve disc 89 is clamped onto the valve seat surface 87, which at least partially closes an outlet cross-section of the flow path 85.

[0031] The valve disc 89, which determines the damping force of the pre-valve 69 and is hereinafter referred to as the pre-valve disc 89, and the valve disc 67, which forms the valve seat surface 65 of the main stage valve 61 and is hereinafter referred to as the valve seat disc 67, are arranged parallel to the valve seat surface 87. An axial distance exists between the two valve discs 67 and 89 as shown by the Fig. Figure 3 shows that this distance is determined in this embodiment by two labyrinth discs 91; 93, which define a pre-opening cross-section within the damping valve assembly. Fig. 5 and Fig. 6) A first labyrinth disc 91 has a closed circumferential ring with radially inwardly directed guide webs 95. Trapezoidal transition cross-sections 97 exist between the guide webs 95. The second labyrinth disc 93 is placed on this first labyrinth disc 91 and has a closed inner ring 99 on which radially outwardly directed connecting webs 101 form C-shaped circumferential webs 103. This creates C-shaped transition cross-sections 105 separated by the connecting webs, with radial flow grooves 107. The valve seat disc 67 now rests on the second labyrinth disc 93. The circumferential width of the flow groove 107 and the material thickness of the second labyrinth disc 93 determine an effective pre-opening cross-section 109. Fig. 3) The open cross-sections in the two labyrinth discs are dimensioned such that axial flow transfer between the two labyrinth discs is ensured, regardless of the rotational arrangement of the two discs 91; 93. The effective size of the pre-opening cross-section 109 is set via the valve disc 67 of the pre-valve, here via the valve seat disc, in that the valve seat disc 67 is elastically deformable in the direction of the pre-valve disc 89.

[0032] In the valve ring 77, a flow connection 111 to the main stage valve 61 is hydraulically connected in parallel to the flow path 85 to the pilot valve 69. The flow connection 111 forms a connection between the control chamber 63 of the main stage valve 61 and the connection port 79. Preferably, the flow connection 111 is implemented in the mounting element 83. The flow path, on the other hand, leads from the connection port 79 to the pilot valve disc 89.

[0033] Furthermore, a flow path 113 is hydraulically connected in parallel to the pre-opening cross-section 109 of the flow connection 111 to the main stage valve 61. Fig. 3) A section of the flow path 113 of the pre-opening cross-section 109 is formed by the fastening element 83, which holds the valve discs 67, 91, 93, and 89 of the pre-valve 69. For this purpose, a constriction is incorporated on the outside of the fastening element 83, which is in axial overlap with the flow path 85 to the valve disc 89. The flow path 113 to the pre-opening cross-section 109 and the flow path 85 to the valve disc 89 of the pre-valve 67 are separated by a support sleeve 115, which is axially supported on the valve ring 77 and on which all the valve discs 67, 91, 93, and 89 held by the fastening element are supported.

[0034] When flow approaches the damping valve assembly 3 via the connection port 79, three volume flows become effective. Assuming a de-energized solenoid coil 43, the main stage valve body 59 is pre-tensioned only by the spring force of the spring assembly 49 on the valve seat disc 67. This setting depends on the desired damping valve characteristic. Regardless of this, the maximum opened pre-opening cross-section 109 is available as a throttling point or for generating damping force.

[0035] Simultaneously, a portion of the volume flow passes through the spoke profile 81 of the valve ring 77 and rests against the pre-valve disc 89. Depending on the pressure level, the pre-valve disc 89 lifts off its valve seat surface 87 of the valve ring 77, making the pre-valve 69 dominant for the damping force characteristic. The main stage valve body 59 can, at least indirectly, act as a stop for the lifting movement of the valve disc 89 of the pre-valve 69. The stop effect is then determined solely by the spring rate of the valve seat disc 67 and the effective force of the spring assembly 49.

[0036] A portion of the flow passes through the flow connection 111 of the fastening element 83 and the control chamber 63 to the fully opened pre-stage valve 57. Even at a relatively low pressure level in the control chamber, the main stage valve body 59 lifts off the valve seat surface 65, thus releasing the main stage valve 61. Consequently, the damping force is determined by the superposition of the pre-stage valve and the main stage valve.

[0037] In the event of maximum current flow to the solenoid coil 43, the pre-stage valve 57 reduces the effective cross-section of the drain opening 53. This increases the hydraulic closing force on the main stage valve 61, and the valve seat disc 69 is elastically deformed in the direction of the pre-valve disc 89. This minimizes or blocks the effective pre-opening cross-section. The adjustment travel of the valve seat disc 69 is limited by the pre-valve disc 89 having a stop surface 121 for the valve disc 67, which determines the pre-opening cross-section. Fig. 7)

[0038] Furthermore, an increased closing force for the pre-valve 69 is set via the contact of the valve seat disc 67 with the pre-valve disc 89. This changes the entire damping force characteristic of the damping valve assembly towards a higher damping force.

[0039] In the Fig. 8 is based on the damping valve device according to the Fig.Figures 2 to 7 illustrate an embodiment in which the valve disc 67 forming the control chamber, i.e., the valve seat disc of the main stage valve 61, is force-transmittingly connected to the pilot valve disc 89. For this purpose, a spring element 117, e.g., a wave spring, is inserted, for example, into the existing free space between the two valve discs 67 and 89, which can, for example, center itself on one or more spacer discs 119. The pilot opening cross-section 109 is formed differently from an opening within the pilot valve disc 89, with the opening being arranged radially outside the at least one spacer disc 119 on a partial circle. The flow path 113 along the fastening means 83 can thus be omitted.

[0040] In this design, any change in the preload of the valve seat disc 67 is translated into a change in the closing force of the pre-valve disc 89. Thus, the damping valve assembly 3 has two adjustable damping valves 61 and 69, which are hydraulically connected in parallel but can be adjusted via a common actuator 41. The dependence of the pre-valve 69 on the main stage valve 61 can be influenced by selecting the spring element 117. Reference sign 1 vibration damper 3 Damping valve device 5 Damping valve device 7 pistons 9 Piston rod 11 Fluid connection 13 Fluid connection 15 piston rod-side working space 17 working space far from piston rod 19 cylinders 21 Compensation area 22 Container pipe 23 first intermediate pipe 25 second intermediate pipe 27 Connection opening 29 Connection opening 31 Connection opening 33 Exit opening 35 Connection opening 37 Exit opening 39 Damping valve housing 41 Actuator 43 Magnetic coil 45 Valve anchors 47 Valve bodies 49 Spring arrangement 51 Housing insert 53 Drain opening 55 Valve seat area 57 Pre-stage valve 59 Main stage valve bodies 61 Main stage valve 63 Control room 65 Valve seat area 67 Valve disc, valve seat disc 69 Pre-valve 71 Connecting opening 73 Interior 75 space 77 Valve ring 79 connection pieces 81 spoke profile 83 Fastening element 85 Flow path 87 Valve seat surface 89 Valve disc, pre-valve disc 91 Labyrinth disc 93 Labyrinth disc 95 Leading platform 97 Cross-section 99 inner ring 101 Connecting bridge 103 Circumferential bridge 105 Cross-section 107 Flow groove 109 Pre-opening cross-section 111 Flow connection 113 Flow path 115 Support sleeve 117 Spring element 119 Spacer 121 Stop surface

Claims

[1] Adjustable damping valve device (3; 5), comprising a main stage valve (61) with a main stage valve body (59), the closing force of which is adjustable on a valve seat surface (65), wherein the valve seat surface (65) is formed by a hydraulically fixed pre-valve (69) which has damping channels and at least one valve disc (67), and is arranged spatially and hydraulically in series with a main stage valve (61), characterized by that the valve seat surface (65) of the main stage valve (61) is formed by the elastic valve disc (67) of the pre-valve (69). [2] Damping valve device according to claim 1, characterized by that a flow connection (111) to the main stage valve (61) is hydraulically connected in parallel to a flow path (85) to the pre-valve (69). [3] Damping valve device according to claim 2, characterized bythat a flow path (113) with a pre-opening cross-section (109) of the flow connection to the main stage valve (111) is hydraulically connected in parallel. [4] Damping valve device according to claim 3, characterized by that the effective size of the pre-opening cross-section (109) is adjustable via at least the valve disc (67) of the pre-valve (69). [5] Damping valve device according to claim 4, characterized by that the valve disc (67) for the main stage valve (61) determines the effective pre-opening cross-section (109). [6] Damping valve device according to claim 4, characterized by that a valve disc (89) of the pre-valve (69) has a stop surface (121) for the valve disc (67) determining the pre-opening cross-section (109). [7] Damping valve device according to one of claims 1 to 6, characterized bythat the main stage valve body (59) at least indirectly forms a stop for the lifting movement of the valve disc (89) of the pre-valve (69). [8] Damping valve device according to at least one of claims 1 to 7, characterized by that the valve disc (67) is adjusted via the closing force on the main stage valve body (59). [9] Damping valve body according to claim 8, characterized by that the closing force on the main stage valve (61) is adjustable by means of a pre-stage valve (69) influencing the pressure in a control chamber (63), wherein a pressurized surface of the control chamber (63) is formed by the valve disc (67) of the pre-valve (69). [10] Damping valve according to claim 9, characterized by that the valve disc (67) of the pre-valve (69) forming the control chamber (63) is connected to the valve disc (89) of the pre-valve (69) in a force-transmitting manner, which determines the damping force of the pre-valve (69). [11] Damping valve device according to at least one of claims 1 to 10, characterized by that the valve discs (67; 89; 91; 93) of the pre-valve (69) are held by a bolt-shaped fastening element (83), wherein the fastening element (83) has the flow connection (111) to the main stage valve (61). [12] Damping valve device according to at least one of claims 1 to 11, characterized by that a section of the flow path (113) of the pre-opening cross-section (109) is formed by at least one valve disc (91; 93) which is spatially arranged between the valve disc (89) of the pre-valve (69) and the valve disc (67) for the main stage valve (59). [13] Damping valve device according to claim 12, characterized by that a section of the flow path (113) of the pre-opening cross-section (109) is formed by a fastening means (83) holding the valve discs (67; 89; 91; 93) of the pre-valve (69). [14] Damping valve body according to claim 3, characterized by that the pre-opening cross-section (109) is formed by an opening of the valve disc (89) of the pre-valve (69), wherein the valve disc (89) cooperates with at least one spacer disc (119) to the valve disc (67) of the main stage valve (59).

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