Abstract
A hydraulic vibration damper, in particular for a vehicle chassis, includes a cylinder tube for receiving a hydraulic fluid. A piston is axially movable within the cylinder tube along a cylinder tube axis and subdivides the cylinder tube into two working chambers. A piston rod is oriented parallel to the cylinder tube axis and is connected to the piston. At least one valve assembly for damping the piston movement in a direction of actuation is arranged at a fluid leadthrough. A bypass duct includes a sub-duct provided in addition to the fluid leadthrough between the two working chambers. A valve arrangement with continuously adjustable damping force is provided which regulates the throughflow through the fluid leadthrough and the sub-duct. The sub-duct includes a throttling mechanism, having a throttle, and a non-return valve. The throttle and the non-return valve of the sub-duct are arranged in series.
Claims
1.-14. (canceled)
15. A hydraulic vibration damper, in particular for a vehicle chassis, comprising: a cylinder tube shaped and sized to receive a hydraulic fluid, a piston that is axially movable within the cylinder tube along a cylinder tube axis and subdivides the cylinder tube into two working chambers, a piston rod that is oriented parallel to the cylinder tube axis and is connected to the piston, a valve assembly is arranged at a fluid leadthrough and is configured to damp the piston movement in a direction of actuation, a bypass duct that includes a sub-duct is provided in addition to the fluid leadthrough between the two working chambers, and a valve arrangement configured to generate a continuously adjustable damping force is configured to regulate the throughflow through the fluid leadthrough and the sub-duct, wherein the sub-duct comprises a throttling mechanism, the throttling mechanism having a throttle and a non-return valve arranged in series with respect to one another.
16. The hydraulic vibration damper of claim 15, wherein the non-return valve has a blocking direction that points to the side facing away from the throttle.
17. The hydraulic vibration damper of claim 15, wherein the non-return valve blocks the volume flow through the sub-duct of the bypass duct for one of two possible movement directions of the piston.
18. The hydraulic vibration damper of claim 15, wherein the non-return valve is formed in that, in its open position, it is flowed through only by the volume flow which flows through the sub-duct at which it is arranged.
19. The hydraulic vibration damper of claim 15, wherein the non-return valve of the sub-duct comprises a non-return disk, wherein said non-return disk has an initial pressure lower than 150000 Pa.
20. The hydraulic vibration damper of claim 19, wherein the non-return disk has an initial pressure lower than 100000 Pa.
21. The hydraulic vibration damper of claim 15, wherein the valve arrangement comprises an electromagnetically actuable, continuously adjustable control valve.
22. The hydraulic vibration damper of claim 15, wherein the vibration damper comprises a further valve assembly configured to damp the piston movement in a second direction of actuation, which further valve assembly is arranged at a further fluid leadthrough.
23. The hydraulic vibration damper of claim 22, wherein the bypass duct comprises a further sub-duct, wherein a further valve arrangement with continuously adjustable damping force is provided which regulates the throughflow through the further fluid leadthrough and the further sub-duct.
24. The hydraulic vibration damper of claim 23, wherein the further sub-duct comprises a further non-return valve and one further throttling mechanism, which comprises a further throttle, wherein the further throttle and the further non-return valve are arranged in series with respect to one another, wherein the further non-return valve is formed in that, in its open position, it is flowed through only by the volume flow which flows through the further sub-duct at which it is arranged.
25. The hydraulic vibration damper of claim 23, wherein the sub-duct is able to be passed through only during the compression stage, and the further sub-duct is able to be passed through only during the rebound stage, of the piston.
26. The hydraulic vibration damper of claim 23, wherein the further valve arrangement comprises a further electromagnetically actuable, continuously adjustable control valve.
27. The hydraulic vibration damper of claim 24, wherein the non-return valves and identical throttling mechanisms of the sub-duct of the bypass duct and the further sub-duct of the bypass duct are identical.
28. The hydraulic vibration damper of claim 23, wherein the bypass duct, including the components of the two sub-ducts, is arranged in a common housing with a first and a second hydraulic chamber, wherein the first hydraulic chamber connects the bypass duct to the first working chamber of the cylinder tube via a first bore, and the second hydraulic chamber connects the bypass duct to the second working chamber of the cylinder tube via a second bore.
29. The hydraulic vibration chamber as claimed in claim 28, wherein the housing is of cylindrical form.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] FIG. 1 shows a block diagram according to an exemplary embodiment of the present invention. The upwardly pointing arrows indicate the throughflow direction for the compression stage of the piston, and the downwardly pointing arrows indicate the throughflow direction for the rebound stage of the piston.
[0037] FIG. 2 shows a block diagram according to a further exemplary embodiment of the present invention.
EMBODIMENTS OF THE INVENTION
[0038] In the various figures, the same parts are always provided with the same reference signs, and will therefore generally also be referred to or mentioned only once in each case.
[0039] FIG. 1 illustrates a block diagram of the hydraulic flow in a vibration damper 1 according to an exemplary embodiment of the invention. The upwardly pointing arrows indicate the throughflow direction for the compression stage of the piston 11, and the downwardly pointing arrows indicate the throughflow direction for the rebound stage of the piston 11. The piston 11 comprises a piston rod 14 and subdivides the cylinder tube 10 into a first working chamber 12 and a second working chamber 13. The two sub-ducts 30, 40 of the bypass duct 20 are illustrated. Here, the sub-duct 30 comprises a series connection of a non-return valve 31 and a throttle 32, connected in series with said non-return valve 31, as part of a throttling mechanism 36. In this case, the blocking direction of the non-return valve 31 points to the side facing away from the throttle 32. The sub-duct 30 is thus able to be passed through for the compression stage of the piston. During the compression stage, the non-return valve 31 is in this case however flowed through not by the volume flow which flows through the valve assembly 51 of the fluid leadthrough 52 but exclusively by the volume flow which flows through the throttle 32 and which is throttled by said throttle 32. This is achieved in that the non-return valve 31 of the sub-duct 30 and the fluid leadthrough 52 with the valve assembly 51 are connected in parallel with one another. During the rebound stage of the piston, the non-return valve 31 blocks the throughflow through the sub-duct 30. Furthermore, the throughflow guide of the compression stage comprises a valve arrangement with continuously adjustable damping force 16, which comprises a continuously adjustable control valve 17, wherein the continuously adjustable control valve 17 is connected in series with the sub-duct 30 and the fluid leadthrough 52. It is possible by way of said continuously adjustable control valve 17 to continuously adjust the damping of the vibration damper for the compression stage of the piston. Here, the further sub-duct 40 comprises a series connection of a further non-return valve 41 and a further throttle 42, connected in series with said further non-return valve 41, as part of a further throttling mechanism 46. In this case, the blocking direction of the further non-return valve 41 points to the side facing away from the further throttle 42. The further sub-duct 40 is thus able to be passed through for the rebound stage of the piston. During the rebound stage, the further non-return valve 41 is in this case however flowed through not by the volume flow which flows through the further valve assembly 61 of the further fluid leadthrough 62 but exclusively by the volume flow which flows through the further throttle 42 and which is throttled by said further throttle 42. This is achieved in that the further non-return valve 41 of the further sub-duct 40 and the further fluid leadthrough 62 with the further valve assembly 61 are connected in parallel with one another. During the compression stage of the piston, the further non-return valve 41 blocks the throughflow through the further sub-duct 40. Furthermore, the throughflow guide of the rebound stage comprises a further valve arrangement with continuously adjustable damping force 18, which comprises a further continuously adjustable control valve 19, wherein the further continuously adjustable control valve 19 is connected in series with the further sub-duct 40 and the further fluid leadthrough 62. It is possible by way of said further continuously adjustable control valve 19 to continuously adjust the damping of the vibration damper for the rebound stage of the piston. According to the exemplary embodiment illustrated in FIG. 1, the throttle 32 (the throttling mechanism 36), the non-return valve 31, the valve arrangement with continuously adjustable damping force 16, the fluid leadthrough 52 and the valve assembly 51 are arranged in a separate housing, which is preferably of cylindrical form, with the further throttle 42 (the further throttling mechanism 46), the further non-return valve 41, the further valve arrangement with continuously adjustable damping force 18, the further fluid leadthrough 62 and the further valve assembly 61 being arranged in a further separate housing, which is preferably of cylindrical form. It is possible that, instead of the continuously adjustable control valve 17 and the further continuously adjustable control valve 19, control valves with fixed, in particular discrete, adjustment stages are used.
[0040] FIG. 2 illustrates a block diagram of the hydraulic flow in a vibration damper 1 according to a further exemplary embodiment of the invention. The piston 11 comprises a piston rod 14 and subdivides the cylinder tube 10 into a first working chamber 12 and a second working chamber 13. The two sub-ducts 30, 40 of the bypass duct 20 are illustrated. Here, the sub-duct 30 comprises a series connection of a non-return valve 31 and a throttle 32, connected in series with said non-return valve 31, as part of a throttling mechanism 36. In this case, the blocking direction of the non-return valve 31 points to the side facing away from the throttle 32. The sub-duct 30 is thus able to be passed through for the compression stage of the piston. During the compression stage, the non-return valve 31 is in this case however flowed through not by the volume flow which flows through the valve assembly 51 of the fluid leadthrough 52 but exclusively by the volume flow which flows through the throttle 32 and which is throttled by said throttle 32. This is achieved in that the non-return valve 31 of the sub-duct 30 and the fluid leadthrough 52 with the valve assembly 51 are connected in parallel with one another. During the rebound stage of the piston, the non-return valve 31 blocks the throughflow through the sub-duct 30. Furthermore, the throughflow guide of the compression stage comprises a valve arrangement with continuously adjustable damping force 16, which comprises a continuously adjustable control valve 17, wherein the continuously adjustable control valve 17 is connected in series with the sub-duct 30 and the fluid leadthrough 52. It is possible by way of said continuously adjustable control valve 17 to continuously adjust the damping of the vibration damper for the compression stage of the piston. Here, the further sub-duct 40 comprises a series connection of a further non-return valve 41 and a further throttle 42, connected in series with said further non-return valve 41, as part of a further throttling mechanism 46. In this case, the blocking direction of the further non-return valve 41 points to the side facing away from the further throttle 42. The further sub-duct 40 is thus able to be passed through for the rebound stage of the piston. During the rebound stage, the further non-return valve 41 is in this case however flowed through not by the volume flow which flows through the further valve assembly 61 of the further fluid leadthrough 62 but exclusively by the volume flow which flows through the further throttle 42 and which is throttled by said further throttle 42. This is achieved in that the further non-return valve 41 of the further sub-duct 40 and the further fluid leadthrough 62 with the further valve assembly 61 are connected in parallel with one another. During the compression stage of the piston, the further non-return valve 41 blocks the throughflow through the further sub-duct 40. Furthermore, the throughflow guide of the rebound stage comprises a further valve arrangement with continuously adjustable damping force 18, which comprises a further continuously adjustable control valve 19, wherein the further continuously adjustable control valve 19 is connected in series with the further sub-duct 40 and the further fluid leadthrough 62. It is possible by way of said further continuously adjustable control valve 19 to continuously adjust the damping of the vibration damper for the rebound stage of the piston. According to the further exemplary embodiment illustrated in FIG. 2, the throttle 32 (the throttling mechanism 36), the non-return valve 31, the valve arrangement with continuously adjustable damping force 16, the fluid leadthrough 52 and the valve assembly 51 and also the further throttle 42 (the further throttling mechanism 46), the further non-return valve 41, the further valve arrangement with continuously adjustable damping force 18, the further fluid leadthrough 62 and the further valve assembly 61 are arranged in a common housing, which is preferably of cylindrical form. It is possible that, instead of the continuously adjustable control valve 17 and the further continuously adjustable control valve 19, control valves with fixed, in particular discrete, adjustment stages are used.
LIST OF REFERENCE SIGNS
[0041] 1 Hydraulic vibration damper
[0042] 10 Cylinder tube
[0043] 11 Piston
[0044] 12 First working chamber
[0045] 13 Second working chamber
[0046] 14 Piston rod
[0047] 16 Valve arrangement with continuously adjustable damping force
[0048] 17 Continuously adjustable control valve
[0049] 18 Further valve arrangement with continuously adjustable damping force
[0050] 19 Further continuously adjustable control valve
[0051] 20 Bypass duct
[0052] 30 Sub-duct
[0053] 31 Non-return valve
[0054] 32 Throttle
[0055] 33 Non-return disk
[0056] 36 Throttling mechanism
[0057] 40 Further sub-duct
[0058] 41 Further non-return valve
[0059] 42 Further throttle
[0060] 46 Further throttling mechanism
[0061] 51 Valve assembly
[0062] 52 Fluid leadthrough
[0063] 61 Further valve assembly
[0064] 62 Further fluid leadthrough
