Vibration damper with a multi-part outer container pipe

Abstract

Vibration damper with a multi-part outer container tube comprising a valve block to which pipe sections of the container tube are connected at the ends, wherein the valve block comprises at least one adjustable damping valve device connected via a fluid channel to a working chamber of a working cylinder, wherein the valve block has an inlet opening to the fluid channel and an outlet opening in the flow direction to a further working chamber, wherein the inlet opening is framed by a pipe stub of the valve block, and an annular profile of the valve block forms a radial guide for a valve housing separate from the valve block, wherein the annular profile and the pipe stub define an annular space to which the outlet opening is connected.

Description

[0001] The invention relates to a vibration damper with a multi-part outer container tube according to the preamble of claim 1.

[0002] From DE 195 42 293 A1, an adjustable vibration damper with a multi-section container tube is known. The container tube comprises an annular valve block with two manually adjustable damping valve devices. Container tube sections are attached to both ends of the valve block, connected at opposite ends to a piston rod guide and an end cap.

[0003] The valve block is manufactured as a milled part and comprises at least one valve seat surface for a valve body as well as a cylindrical section of a valve housing. The cylindrical section carries a cover that closes the valve housing.

[0004] Furthermore, a separating web is provided on the inside of the valve body, which separates a fluid channel on the piston rod side from a fluid channel further away from the piston rod.

[0005] The vibration damper is designed as a monotube vibration damper, meaning the piston rod-side working chamber is separated from an end-side compensation chamber by an axially movable separating piston. Overall, this vibration damper is a design for special applications, thus justifying its complex construction.

[0006] For application involving a significantly larger number of units, this concept should be optimized with regard to manufacturing costs.

[0007] The problem is solved by framing the inlet opening with a pipe stub, and by providing a ring profile of the valve block with a radial guide for a valve housing separate from the valve block, with the ring profile and the pipe stub defining an annular space to which the outlet opening is connected.

[0008] The valve block essentially forms the base for the valve housing of the damping valve assembly. This spatial limitation simplifies both the design of the damping valve assembly and the manufacturing of the valve block. The valve technology is therefore independent of the design of the valve block.

[0009] In a further advantageous embodiment, the valve block features a flow transition to an external accumulator. The external accumulator simplifies the flow paths within the vibration damper. Furthermore, the damping valve assemblies are hydraulically connected upstream of the external accumulator, independent of the operating direction of the vibration damper, so that the pressure in the compensation chamber does not influence the achievable damping force of the damping valve assembly, as is the case in the aforementioned prior art.

[0010] Another measure for simple and cost-effective manufacturing is that the storage tank is fixed to the container pipe by at least one retaining tab. In the immediate transition area from the external storage tank to the valve block, no weld is necessary that could damage a seal between the two assemblies.

[0011] Preferably, the valve block has at least one connection for an external pump. For this purpose, the valve block has a flat surface. The connection is preferably arranged diametrically opposite the accumulator to allow for unrestricted routing of the hydraulic lines, which perform a compensating movement during the operation of the vibration damper.

[0012] Optionally, the valve block has at least one connection channel between a fluid channel and the line connection. This allows the position of the line connection on the vibration damper to be even better adapted to the installation space requirements for the vibration damper in the vehicle.

[0013] In a further advantageous embodiment, the valve block has at least one blind hole opening for a fastening element of the pipe connection. The blind hole opening eliminates the need for a seal on the valve block for the fastening element.

[0014] According to a further subclaim, a separating sleeve, separate from the valve block, is located on the inside of the valve block and hydraulically separates a flow connection between a fluid channel of the inlet opening and a fluid channel of the outlet opening. The use of a separate separating sleeve simplifies the internal geometry of the valve block.

[0015] In a further advantageous embodiment, the separating sleeve comprises a sleeve as its base body and two axially spaced annular webs, the annular webs having different outer diameters. Due to the different outer diameters, seals arranged in the annular webs and aligned with the valve block do not need to overlap any openings during assembly.

[0016] The following description of the figures will be used to explain the invention in more detail.

[0017] It shows: Fig. 1 Hydraulic circuit diagram for the vibration damper according to the invention Fig. 2 Exterior view of the vibration damper according to the invention Fig. 3 Longitudinal section to Fig. 2 Fig. 4. Detailed presentation of Fig. 3 Fig. 5 Longitudinal section to Fig. 2 in the area of ​​the outer storage Fig. 6 Longitudinal section to Fig. 2 in the area of ​​the line connection Fig. 7 and 8 valve block for Fig. 2 in different views

[0018] The Fig. Figure 1 shows a hydraulic circuit diagram with a vibration damper 1, which has a working cylinder 3 in which a piston rod 5 with a piston 7 separates two working chambers 9 and 11. In the simplest case, the piston 7 is designed as a displacer without any valves. A working chamber 9 on the piston rod side is connected via a first fluid channel 13 to a first damping valve assembly 15, which includes at least one adjustable damping valve 17 and a check valve 19. The check valve 19 is closed when fluid flows in from the working chamber 9 on the piston rod side.

[0019] The check valve 19 and the adjustable damping valve 17 are connected to a second fluid channel 21, which leads on one side to a reservoir 23 external to the vibration damper 1 and on the other side to a second damping valve assembly 25. This second damping valve assembly 25 can be identical in design to the first damping valve assembly 15. A check valve 27 within the second damping valve assembly 25 assumes a closed position when damping medium is displaced from a working chamber 11 remote from the piston rod via a third fluid channel 29 into the second damping valve assembly 25. For the inflow of damping medium from the reservoir 23 into a working chamber 9; 11 that expands during the working movement of the vibration damper 1, the corresponding check valve 19; 27 opens, so that the adjustable damping valves 17; 31 within the respective damping valve assembly 15; 25 only have a single flow direction.

[0020] Optionally, a motor-driven pump 33 is assigned to the vibration damper 1, which preferably has two delivery directions and is hydraulically connected in parallel to the two damping valve assemblies 15; 25 via a fourth fluid channel 35, thus also connecting the two working chambers 9; 11. The pump 33 can be used to actively pump damping medium between the two working chambers 9; 11.

[0021] The Fig. 2 shows the vibration damper 1 after Fig. 1 with a multi-part outer container pipe 37, which includes a valve block 39 to which pipe sections 37A; 37B of the container pipe are connected at the ends. The wall thickness of the valve block 39 is significantly greater than that of the pipe sections 37A; 37B.

[0022] The valve block 39 carries the two adjustable damping valve devices 15 and 25, which in this example are radially almost exactly opposite each other. Furthermore, the external storage device 23 is attached to the valve block 39 by means of at least one retaining tab 41.

[0023] Opposite the storage tank 23, the valve block 39 has at least one line connection 43 for the external pump 33. The line connection 43 is fastened to the tank pipe 37 or the valve block 39 by means of screws 45.

[0024] In the Fig. 3 is the vibration damper 1 according to Fig. 2 shown in a longitudinal section. The piston rod-side working chamber 9 has at least one connection opening 47 in the working cylinder 3 to the first fluid channel 13, which is formed by an annular space between the working cylinder 3, the inside of the container tube 37 or the tube section 37A and a piston rod guide 49. The fluid channel 13 opens into a pipe stub 51 of the valve block 39 ( Fig. 4).

[0025] The working chamber 11, located away from the piston rod, is connected, for example, via at least one connection opening 53 in a base section 55 of the working cylinder 3 to the third fluid channel 29. The third fluid channel 29 is also formed by the annular space between the container tube 37 or the pipe section 37B and the working cylinder 3. The third fluid channel 29 is axially closed by a container tube end 57.

[0026] In the excerpt view of the Fig. 4 to the Fig. Figure 3 shows that the first and third fluid channels 13; 29 are separated by a separating sleeve 59, which is separate from the valve block 39. The separating sleeve 59 rests against the inside of the valve block 39, hydraulically separating a flow connection between the fluid channel 13 and an inlet opening 61 and an outlet opening 63 of the first damping valve assembly 15. The second damping valve assembly has identical inlet and outlet openings 65, 67. The separating sleeve 59 has a sleeve as its base body and two axially spaced annular webs 69; 71. Seals 73; 75 are arranged in the annular webs 69; 71, sealing towards the valve block 39. The separating sleeve 59 is hydraulically tightened and fixed to the outside of the working cylinder 3. The annular webs have at least slightly different outer diameters, so that the seals 73; 75 can be pushed over the outflow openings 63; 67 without contact during the assembly of the separating sleeve 59.

[0027] The two ring webs 69; 71 form an annular groove 77, which functionally constitutes part of the second fluid channel 21 to the external storage 23. Furthermore, the ring webs each form end faces of the first and third fluid channels 13; 29, so that the separating sleeve also separates these two fluid channels 13; 29 from each other.

[0028] The damping valve assemblies each comprise an actuator for a pre-stage valve, which in turn controls the adjustable damping valve 17; 31. Regarding the possible design of the damping valve assemblies, reference is made by way of example to DE 10 2021 202 304 A1, the content of which is to be incorporated into this description. Fig. Figure 4 shows that the inlet opening into the damping valve assembly 15 is framed by a pipe stub 51, and an annular profile 79 of the valve block 39 forms a radial guide for a valve housing 81 separate from the valve block. The annular profile 79 and the pipe stub 51 define an annular space 83 to which the outlet opening 63 is connected. The check valve 19; 27 is also arranged in the annular space 83.

[0029] Additionally, the Fig. 5, that the valve block 39 has a flow transition 85 as part of the second fluid channel 21 to the external storage tank 23. The flow transition 85 is formed by a simple stepped opening in the valve block 39, into which a connecting sleeve 87 of the storage tank 23 engages. The connecting sleeve 87 is fixed only to an outer housing 89 of the storage tank 23, e.g., by means of a weld. This weld can be produced during the manufacture of the storage tank 23, so that no heat transfer to the tank pipe 37 occurs from it. The load-bearing function is performed by at least one retaining tab 41, which is arranged at a considerable distance from a seal within the flow transition 85. In this illustration, it can also be seen that the valve block 39 has at least one blind hole 91 for the screw 45 as a fastening means for the pipe connection 43.The flow transition 85 connects the annular groove 77 inside the separating sleeve 59 with a damping medium volume 93 in the reservoir 23. The damping medium volume 93 in the reservoir 23 is pre-charged by a pressurized gas filling 95 in the reservoir 23 via an axially movable separating piston 97. Alternatively, or in combination with the pressurized gas filling 95, a mechanical spring can also be used.

[0030] The Fig. Figure 6 shows the design of the fourth fluid channel 35 for connecting the pump 33 to the two working chambers 9; 11. The fourth fluid channel 35 is connected to the first and third fluid channels 13; 29. ​​These fluid channels 13; 29 provide the connection to the working chamber 9; 11 on the piston rod side and the working chamber 9; 11 on the remote side.

[0031] In conjunction with the Fig. 7 and Fig.Figure 8 shows that the valve block 39 has a flat surface 97 for the line connection 43. In the flat surface 97, the valve block 39 has at least one connection groove 99; 101 between a connection opening 103; 105 and the line connection 43. The connection grooves 103; 105 bridge the axial installation space for the separating sleeve 59 and form a hydraulic extension of the two fluid channels 13; 29 to the respective line connection 43. Reference sign 1 vibration damper 3 working cylinders 5 piston rod 7 pistons 9 piston rod-side working space 11 working space far from piston rod 13 first fluid channel 15 first damping valve device 17 adjustable damping valve 19 Check valve 21 second fluid channel 23 storage 25 second damping valve device 27 Check valve 29 third fluid channel 31 adjustable damping valve 33 Pump 35 fourth fluid channel 37 Container pipe 37A Pipe section of the tank pipe 37B Pipe section of the tank pipe 39 Valve block 41 Mounting flange 43 Line connection 45 screw 47 Connection opening 49 Piston rod guide 51 pipe fittings 53 Connection opening 55 bottom piece 57 Container pipe bottom 59 Separating sleeve 61 Inlet opening 63 Outlet 65 Inlet opening 67 Outlet 69 Ringsteg 71 Ringsteg 73 Seal 75 Seal 77 Ring groove 79 Ring profile 81 Valve housing 83 Ring space 85 Flow transition 87 Connection sleeve 89 cases 91 Blind hole opening 93 Damping medium volume 95 pressurized gas filling 97 Plan area 99 Connection channel 101 Connection channel 103 Connection opening 105 Connection opening QUOTES INCLUDED IN THE DESCRIPTION

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

[0000] DE 195 42 293 A1

[0002] DE 10 2021 202 304 A1

[0028]

Claims

[1] Vibration damper (1) with a multi-part outer container tube (37; 37A; 37B; 39) comprising a valve block (39) to which pipe sections (37A; 37B) of the container tube (37) are connected at their ends, wherein the valve block (39) comprises at least one adjustable damping valve device (15; 25) which is connected via a fluid channel (13; 29) to a working chamber (9; 11) of a working cylinder (3), wherein the valve block (39) has an inlet opening (61; 65) to the fluid channel (13; 29) and an outlet opening (63; 67) in the flow direction to a further working chamber (9; 11; 23), characterized by , that the inlet opening (61; 65) is framed by a pipe stub (51) of the valve block (39), and an annular profile (79) of the valve block (39) forms a radial guide for a valve housing (81) separate from the valve block (39), wherein the annular profile (79) and the pipe stub (51) define an annular space (83) to which the outlet opening (63; 67) is connected. [2] Vibration damper (1) according to claim 1, characterized by , that the valve block (39) has a flow transition (85) to an external storage tank (23). [3] Vibration damper (1) according to claim 2, characterized by , that the storage unit (23) is fixed to the container tube (37; 37A; 37B; 39) via at least one retaining tab (41). [4] Vibration damper (1) according to any one of claims 1 to 3, characterized by that the valve block (39) has at least one line connection (43) for an external pump (33). [5] Vibration damper (1) according to claim 4, characterized by , that the valve block (39) has a flat surface (97) for the pipe connection (43). [6] Vibration damper (1) according to any one of claims 1 to 5, characterized by , that the valve block (39) has at least one connection channel (99; 101) between one of the fluid channels (13; 29) and the line connection (43). [7] Vibration damper (1) according to any one of claims 4 to 6, characterized by , that the valve block (39) has at least one blind hole opening (91) for a fastening means (45) of the line connection (43). [8] Vibration damper (1) according to any one of claims 1 to 7, characterized by , that on the inside of the valve block (39) a separating sleeve (59) is located, which hydraulically separates a flow connection between a fluid channel (13; 29) of the inlet opening (61; 65) from a fluid channel (21) of the outlet opening (63; 67). [9] Vibration damper (1) according to claim 8, characterized in that the separating sleeve (59) has a sleeve as a base body and two axially spaced ring webs (69; 71), wherein the ring webs (69; 71) have different outer diameters.

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