Vibration damper for a vehicle with a damping valve device

Abstract

The present invention relates to a vibration damper (10) for a vehicle, comprising an outer tube (12) and an inner tube (14) arranged coaxially thereto, wherein a compensation chamber (16) for receiving hydraulic fluid is formed between the outer tube (12) and the inner tube (14), and a working piston (18) connected to a piston rod (20) and arranged to be movable back and forth within the inner tube (14), wherein the interior of the inner tube (14) is divided by the working piston (18) into a first working chamber (22) and a second working chamber (24), wherein a central tube (26) is arranged coaxially to the inner tube (14) and within the compensation chamber (16), wherein a damping valve device (54) is attached to the central tube (26), wherein the damping valve device (54) has a housing (28) extending into the compensation chamber (16).

Description

[0001] The invention relates to a vibration damper for a vehicle with a damping valve device having a housing.

[0002] Multi-tube vibration dampers typically do not have a separate gas chamber, so the hydraulic oil and gas are not hermetically separated. Piston rod movements or accelerations of the hydraulic fluid within the vibration damper lead to relatively strong fluctuations in the hydraulic oil level.

[0003] This often leads to a "rupture" of the hydraulic oil column, causing the hydraulic oil and gas to foam up, mixing to such an extent that the oil-gas mixture enters one of the working chambers and / or the valves. In such a case, the function of the vibration damper is severely limited, and the required damping characteristic is no longer achieved. Especially with multi-tube vibration dampers, it is common practice to use elements such as spiral elements in the piston rod-side end area of ​​the vibration damper to prevent foaming.

[0004] For example, DE 11 2019 006 471 T5 describes a vibration damper with a spiral element. However, the installation of the spiral element within the vibration damper is problematic.

[0005] Based on this, it is the object of the present invention to provide a vibration damper for a vehicle in which foaming of the hydraulic fluid is reliably minimized or prevented.

[0006] This object is achieved according to the invention by a device having the features of independent device claim 1. Advantageous further developments emerge from the dependent claims.

[0007] According to a first aspect, a vibration damper for a vehicle comprises an outer tube and an inner tube arranged coaxially thereto, wherein a compensation chamber for receiving hydraulic fluid is formed between the outer tube and the inner tube, and a working piston connected to a piston rod, which is arranged to be movable back and forth within the inner tube, wherein the interior of the inner tube is divided by the working piston into a first working chamber and a second working chamber. A central tube is arranged coaxially to the inner tube and within the compensation chamber, wherein a damping valve device is attached to the central tube. The damping valve device has a housing that extends into the compensation chamber. The housing preferably effects a flow deflection that occurs in such a way that foaming of the hydraulic fluid is reliably minimized.Furthermore, using the damping valve device housing to direct the hydraulic fluid flow within the compensation chamber offers a particularly compact and cost-effective solution. Furthermore, a housing extending into the compensation chamber simplifies the positioning of the damping valve device on the outer tube. A separate component for flow guidance is therefore unnecessary.

[0008] The damping valve device preferably comprises a solenoid valve, wherein the valve position can be adjusted in particular via a coil. The housing of the damping valve device preferably forms the outer surface of the damping valve device at least partially or completely. The housing in particular encloses the interior of the damping valve device at least partially or completely and is preferably arranged at least partially outside the outer tube and extends, for example, in the radial direction of the outer tube. Preferably, the housing is tubular and has, for example, a plurality of different outer diameters. Optionally, the housing has a constant cross-section. The damping valve device has, for example, a cover section that is attached to the housing and has, for example, a power connection for supplying power to the coil.The cover section is particularly attached to the radially outer end of the damping valve device and is preferably connected to the housing, either permanently or detachably, by means of a force-locking and / or positive connection. Optionally, the cover section and the housing are formed integrally or in one piece.

[0009] In the following, the terms "bottom" and "top" refer to the directions when the vibration damper is used as intended, where, for example, the closure assembly and piston rod are located at the top, and the base piece and bottom valve are located at the bottom within the vibration damper. The rebound direction refers to the direction of movement during the rebound stage, with the piston rod moving out of the damper tube, and the compression direction refers to the direction of movement during the compression stage, with the piston rod moving into the damper tube.

[0010] The vibration damper is preferably a multi-tube vibration damper, wherein the compensation chamber is partially filled with a gas, in particular at the upper end. Within the compensation chamber, a central tube is preferably arranged coaxially to the inner tube and the outer tube and in particular fastened to the inner tube. The compensation chamber is in particular designed as an annular chamber and is delimited by the outer tube and the central tube or the inner tube. The outer tube preferably forms at least partially the housing of the vibration damper. The inner surface of the inner tube is preferably designed as a guide for the working piston. The working piston preferably has a valve device through which the first and second working chambers are connected to one another.

[0011] An annular space is preferably formed between the central tube and the inner tube. The inner tube has, in particular, at least one passage opening that fluidically connects the first, piston rod-side working chamber to the annular space, wherein the passage opening is formed in the first working chamber.

[0012] The vibration damper has, in particular, a closure assembly designed and arranged to fluidically seal the interior of the outer tube on the piston rod side. The piston rod-side end of the inner tube is preferably attached to the closure assembly. Opposite the closure assembly, at the end remote from the piston rod, the interior of the outer tube is preferably fluidically sealed by means of a base piece. A base valve is arranged on the base piece, in particular, and is attached to the end of the inner tube remote from the piston rod. The second working chamber is preferably fluidically connected to the compensation chamber via the base valve. The base valve is preferably a check valve through which flow can occur in both directions or only in one direction.For example, the bottom valve is designed as a check valve in the pulling direction, when the piston moves out of the inner tube, and as a detection-generating valve in the pushing direction, when the piston moves into the inner tube.

[0013] One central tube is preferably arranged coaxially with and between the inner tube and the outer tube. The central tube has, for example, a length that corresponds approximately to 40% to 90%, in particular 50% to 80%, of the length of the inner tube 14.

[0014] The central tube is preferably attached to the inner tube via a central tube attachment. The central tube is preferably attached to the inner tube via at least one, in particular via a first and a second, central tube attachment. At least one central tube attachment is arranged at the end of the central tube remote from the piston rod, with a further central tube attachment being arranged, for example, at the end of the central tube closest to the piston rod. The central tube attachment is preferably formed in the central tube. The central tube attachment preferably comprises two constrictions extending radially inwardly around the circumference, with the diameter of the central tube being reduced in the region of the constrictions such that the central tube bears against the inner tube.An annular widening of the central tube is formed between the two constrictions, wherein in the region of the widening the diameter of the central tube is expanded to the previous diameter outside the constriction. The widening is preferably designed such that it forms a closed annular space between the central tube and the inner tube. Within the annular space, for example, a sealing element, in particular a sealing ring, is arranged, which bears against the inner tube and the central tube and forms a fluid-tight seal between them. The central tube attachment preferably represents a seal of the central tube, in particular of the tube element, against the inner tube. The central tube attachment is designed in particular such that it prevents movement of the tube element in the radial direction relative to the inner tube. In the axial direction, the central tube attachment preferably does not fix the tube element to the inner tube.In particular, the center tube is fixed in the axial direction and in the circumferential direction by mounting the damping valve device on the flange area of ​​the center tube.

[0015] The vibration damper preferably has at least one damping valve device, and the central tube in particular has a flange region for attaching the damping valve device to the central tube. The flange region forms a receptacle for the damping valve device; in particular, the flange region forms a fluid inlet and / or fluid outlet of the damping valve device. In particular, the flange region connects the annular space to the damping valve device. The outer tube of the vibration damper preferably has an opening aligned with the flange region for receiving the damping valve device, such that the damping valve device is fluidly connected to the compensation space. The flange region is, for example, formed integrally with the central tube and preferably has a circular cross-section.The preferably tubular flange region extends radially outward from the center tube toward the outer tube. Optionally, the vibration damper has two damping valve devices. For example, the vibration damper has two center tubes, with each damping valve device attached to a respective center tube. It is also conceivable for one of the damping valve devices to be attached to the outer tube via an adapter arranged within the inner tube.

[0016] In particular, a gas volume is accommodated in the upper area of ​​the compensation chamber adjacent to the closure assembly. The vibration damper preferably has precisely one damping valve device, which is designed and configured to dampen the piston rod movement in the tensile and / or compressive directions. The damping valve device can optionally be flowed through in two different flow directions. It is also conceivable for hydraulic fluid to flow through the compensation chamber and the damping valve device exclusively in one direction.

[0017] According to a first embodiment, the outer tube has at least one or precisely one opening through which the housing extends. The housing preferably extends radially from outside the outer tube into the latter. The opening is preferably round, in particular circular or elliptical. In particular, the opening is arranged in alignment with the flange region of the central tube. The diameter of the opening preferably corresponds to the outer diameter of the housing. For example, the vibration damper has two damping valve devices, each with a housing, wherein the outer tube comprises two openings, through which a housing of a respective damping valve device extends.

[0018] According to a further embodiment, the housing rests fluid-tight with its outer surface against the inner surface of the opening of the outer tube, preferably along its entire circumference. This enables easy positioning of the damping valve device on the outer tube.

[0019] According to a further embodiment, the housing has a collar region formed at the end of the housing pointing toward the central tube. The collar region is preferably formed integrally or in one piece with the housing. The collar region preferably extends in the radial direction of the outer tube and forms the front end of the housing. The collar region preferably extends radially from the opening into the compensation chamber. For example, the collar region is arranged entirely within the compensation chamber and in particular the opening of the outer tube.

[0020] According to a further embodiment, a gap is formed between the central tube and the housing, in particular the collar region, through which gap hydraulic fluid can flow. The housing, in particular the collar region, is preferably arranged at a distance from the inner tube and does not rest against it. The gap is in particular annular, wherein the ring diameter is smaller at the section of the collar region pointing in the tensile direction, in particular in the direction of the closure assembly, than at the section of the collar region pointing in the compression direction, in particular in the direction of the base valve. Over the circumference of the collar region, the gap preferably has a varying ring diameter. The ring diameter of the gap preferably decreases in the tensile direction Z, in particular from the base piece-side end of the collar region towards the closure assembly-side end of the collar region, for example constantly.

[0021] According to a further embodiment, the collar region has a recess. The recess preferably forms an outlet for discharging hydraulic fluid from the damping valve device into the compensation chamber. For example, the collar region has a plurality of recesses, which preferably point toward the base valve.

[0022] According to a further embodiment, the recess extends from the end of the collar region facing toward the central tube to the opening of the outer tube. The recess preferably extends from the end of the collar region, preferably from the end of the collar region facing toward the central tube, in a radial direction, preferably toward the outer tube. In particular, the recess extends exactly to the opening in the outer tube and, for example, terminates with it.

[0023] According to a further embodiment, the recess is formed in the region of the collar area facing in the pressure direction, in particular in the direction of the base valve. The recess is formed in particular in the region of the collar area facing downwards, in the direction of the base valve. The recess in the collar area ensures a downward flow deflection in the pressure direction, in particular in the direction of the base valve within the compensation chamber. As a result, the hydraulic fluid is directed downwards and around the center tube after exiting the damping valve device. According to the inventor's discovery, this ensures a calming flow and comparatively low foaming of the hydraulic fluid.

[0024] According to a further embodiment, the recess at least partially forms the gap. The recess enlarges the gap and thus ensures targeted flow guidance.

[0025] According to a further embodiment, the gap formed by the recess has an annular diameter that corresponds to the annular diameter of the compensation chamber. This exposes the entire annular diameter of the compensation chamber to hydraulic fluid, so that the hydraulic fluid flows largely through the gap formed by the recess.

[0026] According to a further embodiment, the recess forms an outlet for discharging hydraulic fluid from the damping valve device, in particular into the compensation chamber.

[0027] According to a further embodiment, the central tube has a flange region to which the damping valve device is fastened. The flange region of the central tube is also referred to as a chimney and is fastened to the damping valve device. The flange region preferably extends in the radial direction of the central tube and is in particular formed integrally or in one piece with it. The damping valve device preferably comprises a tubular inlet for admitting and / or discharging hydraulic fluid into or out of the damping valve device. The inlet is arranged, for example, within the flange region and preferably rests with its outer surface against the inner surface of the flange region, in particular in a fluid-tight manner. The inlet is preferably detachably connected to the flange region, in particular by means of a force-fitting and / or form-fitting connection.

[0028] The damping valve device further comprises, for example, a valve body that interacts with valve discs, for example. The valve body is, for example, formed integrally or in one piece with the inlet. In particular, the housing has a radially inward-facing projection against which the valve body is supported and, in particular, abuts against it. This simplifies the positioning of the damping valve device during assembly on the outer tube. Description of the drawings

[0029] The invention is explained in more detail below using several embodiments with reference to the accompanying figures. Fig. 1 shows a schematic representation of a vibration damper in a longitudinal sectional view according to an embodiment. Fig. 2 shows a schematic representation of a damping valve device in a longitudinal sectional view according to a further embodiment.

[0030] Fig. 1 shows a vibration damper 10, wherein the vibration damper 10 is a multi-tube vibration damper, for example a two-tube vibration damper. The vibration damper 10 has an outer tube 12, which forms an outer surface, in particular a housing, of the vibration damper 10. An inner tube 14 is arranged within the outer tube 12 coaxially therewith. Between the outer tube 12 and the inner tube 14, a compensation chamber 16 is formed, which is preferably at least partially filled with a hydraulic fluid. The compensation chamber 16 is preferably partially filled with a gas.

[0031] Within the inner tube 14, a working piston 18 connected to a piston rod 20 is arranged such that it is movable within the inner tube 14, wherein the inner tube is preferably designed as a guide for the working piston 18. The working piston 18 preferably has a valve device which is Fig. 1 is not shown in detail. The working piston 18 divides the interior of the inner tube 14 into a first working chamber 22, which is arranged on the piston rod side, and a second working chamber 24, which is arranged remote from the piston rod. Within the compensation chamber 16, a central tube 26 is arranged coaxially with and between the inner tube 14 and the outer tube 12.

[0032] The interior of the outer tube 12 is fluidically sealed on the piston rod side by means of a sealing package 34. Opposite the sealing package 34, at the end remote from the piston rod, the interior of the outer tube 12 is fluidically sealed by means of a base piece 36. A base valve 38, for example, is arranged on the base piece 36 and is attached in particular to the end of the inner tube 14 remote from the piston rod. The base valve 38 is preferably a check valve through which flow can occur in both directions or only in one direction. For example, the base valve 38 is designed as a check valve in the pulling direction, during a piston movement out of the inner tube 14, and as a signal-generating valve in the pushing direction, during a piston movement into the inner tube. The second working chamber 24 is preferably fluidically connected to the compensation chamber 16 via the base valve 38.The piston rod-side end of the inner tube 14 is preferably attached to the closure package 34.

[0033] The center tube 26, for example, has a length that corresponds approximately to 50 to 80% of the length of the inner tube 14. The center tube 26 is attached in particular to the inner tube 14 via a first and a second center tube attachment 40, 42. The first center tube attachment 40 is arranged at the end of the center tube 26 closest to the piston rod, and the second center tube attachment 42 is arranged at the end of the center tube 26 remote from the piston rod. Preferably, the center tube 26 is attached directly to the inner tube 14. The center tube attachment 40, 42 preferably comprises two radially inwardly circumferentially extending constrictions 44a,b, wherein in the region of the constrictions 44a,b, the diameter of the center tube 26 is reduced such that the center tube 26 bears against the inner tube 14.The axially inward, first constriction 44a is followed by a particularly annular widening 46 of the inner tube 14, wherein in the region of the widening 46 the diameter of the central tube 26 is expanded to the previous diameter outside the constriction 44. The widening 46 is followed in the axially outward direction by the second constriction 44b and forms the end of the central tube 26. With the exception of the central tube attachment 40, 42, the central tube 26 preferably has a constant diameter and cross-section. The widening 46 is preferably designed such that it forms a closed annular space between the central tube 26 and the inner tube 14. Within the annular space, for example, a sealing element, in particular a sealing ring, is arranged, which rests against the inner tube 14 and the central tube 26 and forms a fluid-tight seal between them.Preferably, the first and second center tube attachments 40, 42 each have an annular space with a sealing ring. The widened portion 46 and constricted portions 44a,b are preferably formed in the center tube.

[0034] An annular space 13 is formed between the central tube 26 and the inner tube 14. At least one passage opening 17 is formed in the inner tube 14, which fluidically connects the first working chamber 22 to the annular space 13. The passage opening 17 is formed in the first working chamber 22.

[0035] The central tube 26 is preferably formed from a metal. For example, the central tube 26 has a flange region 52 for attaching a damping valve device 54 to the central tube 26. The flange region 52 is, for example, formed integrally with the central tube 26 and preferably has a circular cross-section. The preferably tubular flange region 52 extends radially outward from the central tube 26, toward the outer tube 12. The flange region 52 forms a receptacle for the damping valve device 54; in particular, the flange region 52 forms a fluid inlet and / or fluid outlet of the damping valve device 54. The flange region 52 connects the annular space 13 to the damping valve device 54.The outer tube 12 preferably has an opening 48 aligned with the flange region 52 for receiving the damping valve device 54, so that the damping valve device 54 is fluidly connected to the compensation chamber 16.

[0036] For example, a pull stop 50 is attached to the piston rod 20, which limits a movement of the working piston 18 in the pulling direction Z.

[0037] The hydraulic fluid can preferably flow through the compensation chamber 16 in two or only one flow direction. In the compression stage of the vibration damper 10, when the working piston 18 retracts into the inner cylinder 14, a flow in the tension direction from bottom to top, for example, occurs in the compensation chamber. This flow direction in the compensation chamber 16 preferably points from the base valve 38 towards the closure assembly 34. In the rebound stage of the vibration damper 10, with a piston rod movement in the tension direction Z, the flow direction in the compensation chamber 16 points, for example, from top to bottom, in particular from the closure assembly 34 towards the base valve 38. The damping valve device 54 can optionally be flowed through in two different flow directions. For example, the compensation chamber 16 and the damping valve device 54 can only be flowed through in one direction by hydraulic fluid.For example, the vibration damper 10 has precisely one damping valve device 54, which is designed and configured to dampen the piston rod movement in the pulling direction Z and / or in the pushing direction D. It is also conceivable for the vibration damper to have two damping valve devices, each designed and configured to dampen the piston rod movement in the pulling direction Z and / or in the pushing direction D. In particular, a gas volume is accommodated in the upper region of the compensation chamber 16 adjacent to the closure package 34.

[0038] Fig.2 shows the damping valve device 54 in a detailed view. The damping valve device 54 is, for example, a solenoid valve, wherein the valve position can be adjusted in particular via a coil. The damping valve device 54 preferably has a housing 28 which forms an outer surface of the damping valve device 54. The housing 28 encloses the interior of the damping valve device 54, in particular at least partially or completely. The housing 28 is preferably arranged at least partially outside the outer tube 12 and extends, for example, in the radial direction of the outer tube 12. The housing 28 is preferably tubular and, for example, has a plurality of different outer diameters. It is also conceivable for the housing 28 to have a constant cross-section.The damping valve device 54 has, for example, a cover section 30 that is attached to the housing 28 and, for example, has a power connection for supplying power to the coil. The cover section 30 is attached in particular to the radially outer end of the damping valve device 54 and is preferably fixedly or detachably connected to the housing 28 by means of a force-locking and / or positive connection. For example, the cover section 30 and the housing 28 are formed integrally or in one piece.

[0039] The housing 28 preferably extends radially from outside the outer tube 12 into the outer tube 12. In particular, the housing 28 extends through the opening 48 in the outer tube 12 into the outer tube. The opening 48 is preferably round, in particular circular or elliptical.

[0040] The outer surface of the housing 28 preferably bears fluid-tight against the inner surface of the opening 48 of the outer tube 12. The housing 28 preferably has a collar region 32, which is formed on the end of the housing 28 pointing in the direction of the central tube 26 and is preferably formed integrally or in one piece with the housing 28. The collar region 32 preferably extends in the radial direction of the outer tube 12 and forms the front end of the housing 28. The collar region 32 preferably extends from the opening 48 in the radial direction into the compensation chamber 16. For example, the collar region 32 is arranged entirely within the compensation chamber 16 and in particular the opening 48 of the outer tube 12. The housing 28, in particular the collar region 32, is preferably arranged at a distance from the inner tube 14 and does not bear against it.Preferably, a gap 56 through which hydraulic fluid can flow is formed between the central tube 26 and the housing 28, in particular in the collar region 32. The gap 56 is in particular annular, wherein the ring diameter is smaller at the section of the collar region 32 facing in the direction of the closure assembly 34 than at the section of the collar region 32 facing in the direction of the base valve 38. Over the circumference of the collar region 32, the gap 56 preferably has a varying ring diameter. Preferably, the ring diameter of the gap 56 decreases in the pulling direction Z, in particular from the base piece-side end of the collar region 32 towards the closure assembly-side end of the collar region 32, for example, constantly.

[0041] The collar region 32 preferably has at least one or more recesses 58. The recess 58 extends, for example, from the front end of the collar region 32 pointing in the direction of the central tube 26 in the radial direction, in particular in the direction of the outer tube 12. In particular, the recess 58 extends exactly as far as the opening 48 in the outer tube 12 and, for example, terminates therein. The recess 58 is formed in particular in the region of the collar region 32 pointing downwards, in the direction of the base valve 38. Preferably, the recess 58 at least partially forms the gap 56. The gap 56 formed by the recess 58 preferably has an annular diameter that corresponds to the annular diameter of the compensation chamber 16. The collar region 32 has, for example, a plurality of recesses that are arranged such that they point in the direction of the base valve 38.Preferably, the recess 58 forms an outlet for discharging hydraulic fluid from the damping valve device 54, in particular into the compensation chamber 16.

[0042] The central tube 26 has, for example, a flange region 52, which is also referred to as a chimney and is fastened to the damping valve device 54. The flange region 52 preferably extends in the radial direction of the central tube 26 and is in particular formed integrally or in one piece with it. The damping valve device 54 preferably comprises a tubular inlet 60 for admitting and / or discharging hydraulic fluid into the damping valve device 54. The inlet 60 is arranged, for example, within the flange region 52 and preferably rests with its outer surface against the inner surface of the flange region 52, in particular in a fluid-tight manner. A sealing element, such as a sealing ring, is arranged, for example, between the outer surface of the inlet 60 and the inner surface of the flange region 52. The inlet 60 is preferably detachably connected to the flange region 52, in particular by means of a force-fitting and / or form-fitting connection.

[0043] The damping valve device 54 further comprises, for example, a valve body 62, which preferably interacts with valve discs (not shown). The valve body 62 is, for example, formed integrally or in one piece with the inlet 60. In particular, the housing 28 has a radially inwardly facing projection against which the valve body 62 is supported and, in particular, bears against it.

[0044] During operation of the vibration damper 10, it is operated, for example, in the compression stage with a piston rod movement in the compression direction D or in the rebound stage with a piston rod movement in the tension direction Z. For example, in the compression stage and in the rebound stage, the hydraulic fluid flows from the annular space between the center tube 26 and the inner tube 14 and then through the inlet 60 into the damping valve device 54. The hydraulic fluid flows through the outlet formed by the recess from the damping valve device 54 into the compensation chamber 16. The collar region 32 preferably serves as a flow guide element, through which a flow deflection in the compression direction D, in particular in the direction of the base valve 38, occurs. Preferably, only a comparatively small portion of the hydraulic flow flows through the gap 56 in the tension direction Z, in particular in the direction of the closure assembly 34.This flow redirection reliably minimizes foaming of the hydraulic fluid. Preferably, the damping valve device 54 is mounted in a region of the outer tube 12 in which the outer tube 12, in particular the compensation chamber 16, is filled exclusively with hydraulic oil and not with gas. List of reference symbols 10 vibration dampers 12 Outer tube 13 Annular space 14 inner tube 16 Compensation room 17 Passage opening 18 working pistons 20 piston rod 22 first, piston rod side working chamber 24 second working chamber remote from the piston rod 26 center tube 28 housings 30 lid section 32 collar area 34 closure package 36 base piece 38 bottom valve 40 Center tube attachment 42 Center tube attachment 44a, b Constrictions 46 Widening 48 Opening 50 pull stop 52 flange area 54 Damping valve device 56 gap 58 recess 60 entrance 62 valve bodies QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 11 2019 006 471 T5

[0004]

Claims

[1] Vibration damper (10), for a vehicle, comprising: - an outer tube (12) and an inner tube (14) arranged coaxially to it, wherein a compensation chamber (16) for receiving hydraulic fluid is formed between the outer tube (12) and the inner tube (14), and - a working piston (18) connected to a piston rod (20), which is arranged to be movable back and forth inside the inner tube (14), wherein the interior of the inner tube (14) is divided by the working piston (18) into a first working chamber (22) and a second working chamber (24), - wherein a central tube (26) is arranged coaxially to the inner tube (14) and within the compensation space (16), - wherein a damping valve device (54) is attached to the central tube (26) - characterized by , that - the damping valve device (54) has a housing (28) which extends into the compensation chamber (16). [2] Vibration damper (10) according to claim 1, wherein the outer tube (12) has an opening (48) through which the housing (28) extends. [3] Vibration damper (10) according to claim 2, wherein the housing (28) is fluid-tight against the inner surface of the opening (48) of the outer tube (12) with its outer surface. [4] Vibration damper (10) according to one of the preceding claims, wherein the housing (28) has a collar area (32) which is formed at the end of the housing (28) pointing towards the central tube (26). [5] Vibration damper (10) according to claim 4, wherein a gap (56) is formed between the central tube (26) and the housing (28), through which hydraulic fluid can flow. [6] Vibration damper (10) according to claim 4 or 5, wherein the collar area (32) has a recess (58). [7] Vibration damper (10) according to claim 6, wherein the recess (58) extends from the end of the collar area (32) pointing towards the central tube (26) to the opening (48) of the outer tube (12). [8] Vibration damper (10) according to claim 6 or 7, wherein the recess (58) is formed on the area of ​​the collar region (32) that points in the direction of pressure (D). [9] Vibration damper (10) according to one of claims 5 to 8, wherein the recess (58) at least partially forms the gap (56). [10] Vibration damper (10) according to claim 9, wherein the gap (56) formed by the recess (58) has a ring diameter corresponding to the ring diameter of the compensation space (16). [11] Vibration damper (10) according to one of claims 6 to 10, wherein the recess (58) forms an outlet for releasing hydraulic fluid from the damping valve assembly (54). [12] Vibration damper (10) according to one of the preceding claims, wherein the central tube (26) has a flange area (52) to which the damping valve device (54) is attached.

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