SLEEVE FOR A DAMPER, DAMPER, SYSTEM, MANUFACTURING METHOD FOR A SLEEVE, MANUFACTURING METHOD FOR A DAMPER

Abstract

A substantially tubular sleeve is arranged in a damping space of the damper containing a damping fluid and has at least one recess at least in an inner face of the sleeve. The recess defines a flow channel for the damping fluid for adaptation of the flow impedance (F) for the damping fluid at least in a direction along a longitudinal axis (LA) of the sleeve. The sleeve is rigidly and releasably connected to the outer body by a number of contact surfaces on an outer surface of the sleeve and/or has at least one guide surface arranged on an inner surface of the sleeve for guiding the piston over the travel path (H).

Also disclosed is a system for modular assembly of a plurality of dampers, method of manufacture for a sleeve, and a method of production for a damper.

Claims

1-11. (canceled)

12: A substantially tubular sleeve for a damper, in particular a industrial shock absorber, wherein the sleeve is configured to be arranged in a damping space of the damper containing a damping fluid and comprises at least one recess at least in an inner face of the sleeve, wherein the recess defines a flow channel for the damping fluid for adaptation of the flow impedance (F) for the damping fluid at least in a direction along a longitudinal axis (LA) of the sleeve, wherein a width of the recess along the longitudinal axis increases parabolically from one end of the recess to the other end of the recess.

13: The sleeve according to claim 12, wherein the recess a. is modulated along the longitudinal axis (LA) in order to set the flow impedance (F), wherein the recess is preferably i. modulated with respect to a shape and/or surface of a cross-section orthogonally to the longitudinal axis (LA), particularly preferably with respect to a width (B) in a circumferential direction of the sleeve and/or a depth (T) in a radial direction of the sleeve; ii. modulated with respect to a position of the recess in a circumferential direction of the sleeve and/or iii. actively modulated with respect to a surface composition and/or surface morphology with a flow-dynamic effect; b. has a depth (T) in a radial direction of the sleeve which is less than the wall thickness of the sleeve in the same region of the sleeve and/or c. comprises at least one flow-dynamically effective coating.

14: The sleeve according to claim 12, wherein the sleeve a. is designed in its structure, in particular with respect to a wall thickness of the sleeve and/or a material of the sleeve, to provide more savings on material than necessary with respect to the mechanical and/or thermal load-bearing capacity in the damping operation of the damper, wherein preferably on an outer surface of the sleeve a number of contact surfaces are provided for diverting mechanical and/or thermal load into a damper, particularly preferably uniformly distributed over the outer surface of the sleeve; b. comprises a metal, preferably a steel, a plastic and/or a composite material; c. comprises, on an inner surface of the sleeve, at least one coating, preferably for setting a friction behaviour relative to a piston of the damper, and/or d. comprises, on at least one end face of the sleeve, a closure element which closes the interior of the sleeve at one end, preferably in a fluid-tight manner.

15: A damper, in particular an industrial shock absorber, comprising a. a substantially tubular outer body configured to accommodate mechanical and/or thermal loads during operation of the damper; b. a damping space in the outer body configured to accommodate a damping fluid and c. a piston which is guided along a longitudinal axis of the outer body over a travel path (H) in the outer body, wherein the piston divides the damping space into a first fluid chamber and a second fluid chamber; said damper further comprising a substantially tubular sleeve having at least one recess at least in an inner face of the sleeve, wherein the recess defines a flow channel for the damping fluid for adaptation of the flow impedance (F) for the damping fluid at least in a direction along a longitudinal axis (LA) of the sleeve, wherein a width of the recess along the longitudinal axis increases parabolically from one end of the recess to the other end of the recess, said substantially tubular sleeve being arranged in the damping space, wherein the sleeve is rigidly and preferably releasably connected to the outer body by a number of contact surfaces on an outer surface of the sleeve and has at least one guide surface arranged on an inner surface of the sleeve for guiding the piston over the travel path (H).

16: The damper according to claim 15, wherein a volume between the sleeve and the piston forms at least one flow channel connecting the first fluid chamber to the second fluid chamber in a fluid-conducting manner, wherein the flow channel is preferably defined by a recess in an inner surface of the sleeve and/or a groove on an outer surface of the piston.

17: The damper according to claim 16, wherein a. the guide face interacts in a fluid-tight manner with an outer surface of the piston; b. the guide face and/or the outer surface of the piston has a coating for increasing the thermal conductivity, for reducing friction and/or for reducing wear, c. the contact surfaces are connected to the outer body in a thermally conductive manner and/or for mechanical transmission of force, and/or d. the contact surfaces occupy substantially the entire outer surface of the sleeve.

18: A system for modular assembly of a plurality of dampers according to claim 16, which differ with respect to their damping characteristics, wherein a. a number of sleeves which differ in particular with respect to the flow impedance (F) for the damping fluid between the first fluid chamber and the second fluid chamber, and b. a number of further components of the damper, wherein the further components are standardised for each damper of the plurality of different dampers.

19: A method of manufacture for a substantially tubular sleeve for a damper, which sleeve comprises at least one recess at least in an inner face of the sleeve, wherein the recess defines a flow channel for a damping fluid for adaptation of the flow impedance (F) for the damping fluid at least in a direction along a longitudinal axis (LA) of the sleeve, wherein a width of the recess along the longitudinal axis increases parabolically from one end of the recess to the other end of the recess, wherein the method of manufacture comprises at least the introduction of a recess at least into an inner surface of the sleeve.

20: The method of manufacture according to claim 19, wherein a. the introduction takes place by laser cutting, preferably by ultra-short pulse lasers, and/or b. the method of manufacture comprises reworking, preferably deburring and/or surface treatment, at least of the recess.

21: A method of production for a damper, in particular industrial shock absorber, comprising a. a substantially tubular outer body configured to accommodate mechanical and/or thermal loads during operation of the damper; b. a damping space in the outer body configured to accommodate a damping fluid and c. a piston which is guided along a longitudinal axis of the outer body over a travel path (H) in the outer body, wherein the piston divides the damping space into a first fluid chamber and a second fluid chamber; said damper further comprising a substantially tubular sleeve having at least one recess at least in an inner face of the sleeve, wherein the recess defines a flow channel for the damping fluid for adaptation of the flow impedance (F) for the damping fluid at least in a direction along a longitudinal axis (LA) of the sleeve, wherein a width of the recess along the longitudinal axis increases parabolically from one end of the recess to the other end of the recess, arranged in the damping space, wherein the sleeve is rigidly and preferably releasably connected to the outer body by a number of contact surfaces on an outer surface of the sleeve and has at least one guide surface arranged on an inner surface of the sleeve for guiding the piston over the travel path (H), wherein the method of production comprises at least the manufacture of the sleeve and the installation of the sleeve into the outer body.

22: The method of production according to claim 21, wherein the manufacture of the sleeve comprises at least the introduction of a recess at least into an inner surface of the sleeve.

23: The method of production according to claim 21, wherein the method of production comprises selection of a sleeve from a number of sleeves which differ in particular with respect to the flow impedance (F) for the damping fluid between the first fluid chamber and the second fluid chamber.

24: The method of production according to claim 21, further comprising selection of a number of further components of the damper, wherein the further components are standardised for each damper of the plurality of different dampers.

Description

[0042] In the drawings:

[0043] FIG. 1 shows a schematic longitudinal section through a sleeve according to the invention;

[0044] FIG. 2 shows a schematic cross-section through a sleeve according to the invention;

[0045] FIG. 3 shows a schematic longitudinal section through a further sleeve according to the invention;

[0046] FIG. 4 shows a schematic longitudinal section through a damper according to the invention;

[0047] FIG. 5 shows exemplary progressions of the width of a recess of a sleeve according to the invention and a resulting flow impedance and

[0048] FIG. 6 shows a schematic representation of a production method according to the invention.

[0049] FIG. 1 shows a schematic longitudinal section through a sleeve 12 according to the invention. The illustrated sleeve 12 has the shape of a hollow cylinder with a longitudinal axis LA. On an inner surface 12i the sleeve 12 has a recess 20, which together with a piston 19 guided in the sleeve 12 defines a flow channel for a damping fluid between a first fluid chamber 111 of a damping space of a damper 100 and a second fluid chamber 112. The recess-free region of the inner surface 12i forms a guide face 12-19 for guiding the piston 19, and the piston 19 preferably bears on this guide face in a fluid-tight manner. An outer surface 12a of the sleeve 12 can form a contact surface for mechanical and/or thermal connection of the sleeve 12 to an outer body (not illustrated) of the damper 100.

[0050] The illustrated recess 20 is modulated along the longitudinal axis LA for setting the flow impedance for the damping fluid, for example in that a first region of the recess 20 has a first depth T1 orthogonal to the longitudinal axis LA and a second region of the recess has a greater second depth T2. If the piston 19 is located in the region of the first depth T1 (FIG. 1a), as a result a flow channel is defined which has a smaller flow cross-section and thus a higher flow impedance than if the piston 19 is located in the region of the second depth T2 (see FIG. 1b). Consequently the flow impedance for the damping fluid and consequently the damping force of the damper 100 is dependent upon the position of the piston 19 along its travel path inside the sleeve 12.

[0051] FIG. 2 shows a schematic cross-section through a sleeve 12 according to the invention. The sleeve 12, which for example has a hollow cylindrical shape, comprises on an inner surface a recess 20, which together with a piston 19 guided in the sleeve 12 defines a flow channel for a damping fluid. The flow impedance for the damping fluid in the flow channel can be set by the choice of a depth T of the recess 20 in a radial direction of the sleeve 12 and/or a width B of the recess 20 in a circumferential direction of the sleeve 12.

[0052] FIG. 3 shows a schematic longitudinal section through a further sleeve 12 according to the invention. The illustrated sleeve 12 is hollow cylindrical with a longitudinal axis LA and comprises at least one recess 20, which is constructed as a continuous opening from an inner surface 12i to an outer surface 12a of the sleeve 12, so that the depth of the recess 20 corresponds to a wall thickness of the sleeve 12. The sleeve preferably comprises four recesses 20 which are uniformly distributed about the longitudinal axis LA and/or are of the same kind. A width B of the recess in a circumferential direction of the sleeve 12 decreases along the longitudinal axis LA from a first end E1 of the recess 20 to a second end E2 of the recess 20, so that the recess 20 in a wall plane of the sleeve 12 for example describes a parabolic shape.

[0053] FIG. 4 shows a schematic longitudinal section through a damper 100 according to the invention. The illustrated damper 100 comprises a hollow cylindrical outer body 1 with a longitudinal axis of the outer body ALA. The sleeve 12 illustrated in FIG. 3 is arranged in the outer body 1 in such a way that the longitudinal axis of the sleeve 12 coincides with the longitudinal axis of the outer body ALA and an outer surface 12a of the sleeve forms a contact surface 12-1 for mechanical and/or thermal connection to the outer body 1. The sleeve 12 is fixed releasably in the outer body 1 by a closure 2 and a passage 15 for a piston rod 3. The inner space of the sleeve 12 forms the damping space 110 of the damper 100, which can be filled with a damping fluid through a filling valve 9 in the closure 2. In the illustrated example the piston 19 of the damper 100 is located at the first end E1 of the recess 20 of the sleeve 12 in the damping space 110.

[0054] If the piston rod 3 is pressure-loaded, as a result the piston 19 is pushed along its travel path from the first end E1 to the second end E2 of the recess 20. In this case the damping fluid flows from a first fluid chamber 111 in the direction of movement in front of the piston 19 through the flow channel defined by the recess 20 with the outer body 1 and the piston 19 into a second fluid chamber 112 behind the piston 19. The flow impedance occurring in this case for the damping fluid determines the damping force of the damper 100. Since the width B of the illustrated recess 20 decreases from the first end E1 to the second end E2, the flow cross-section of the flow channel also decreases if the piston, on its travel path along the longitudinal axis of the outer body ALA, moves from the first end E1 to the second end E2. Consequently the flow impedance for the damping fluid and the damping force increase over the travel path H if the piston moves from the first end E1 to the second end E2.

[0055] In order that, when the piston rod 3 is relieved of load, the piston 19 can be easily returned into its illustrated initial position, a number of non-return valves 8 can be provided in the piston 19. Due to the non-return valves 8 the damping fluid can flow with low flow impedance from the second fluid chamber 112 into the first fluid chamber 111 while the piston 19 moves from the second end E2 back to the first end E1.

[0056] FIG. 5 shows exemplary progressions of the width B of a recess 20 of a sleeve 12 (FIG. 5a) according to the invention and a flow impedance F (FIG. 5b) resulting therefrom. The sleeve 12 of the damper 100 illustrated in FIG. 4 shows for example a recess 20 having a width B which decreases steadily from a first width B1 at the first end E1 of the recess 20 over the travel path H of the piston to a second width B2 at the second end E2 of the recess 20. Proportionally to the width B, the flow cross-section Q of the flow channel defined by the recess 20 with the piston 19 also decreases if the piston 19 moves along its travel path H from the first end E1 to the second end E2.

[0057] The flow impedance F is inversely proportional to the flow cross-section Q and therefore shows the increasing progression from a first flow impedance F1 to a second flow impedance F2 illustrated in FIG. 5b if the piston 19 moves along its travel path H from the first end E1 to the second end E2. Since the damping force K of the damper 100 is determined by the flow impedance F, the damping force K shows qualitatively the same progression as a function of the travel path H as the flow impedance F. By corresponding configuration of the recess 20 almost any progressions of the damping force K as a function of the travel path can be set.

[0058] FIG. 6 shows a schematic representation of a production method 400 according to the invention for a damper 100 according to the invention. The production method 400 comprises the manufacture 410 of a number of sleeves, in particular different from one another, for example by a method of manufacture 300 according to the invention. The method of manufacture 300 according to the invention comprises the introduction 310 of a recess in the sleeve, which can be followed by reworking 320 of the sleeve, for example deburring, in particular in the region of the recess.

[0059] The illustrated method of production 400 comprises selection 430 of a sleeve from a number of sleeves which differ in particular with respect to the flow impedance for the damping fluid between the first fluid chamber and the second fluid chamber of the damper 100. Next the installation 420 of the sleeve in the outer body of the damper 100 takes place, for example in that the sleeve 12 is inserted into the outer body, in particular with a precise fit, and is fastened there by locking means (not illustrated) such as a closure.

[0060] Features which are illustrated in the context of an example can also be combined differently according to the invention.

LIST OF REFERENCES

[0061] 1 outer body [0062] 2 closure [0063] 3 piston rod [0064] 8 non-return valve [0065] 9 filling valve [0066] 12 pressure sleeve [0067] 12a outer surface [0068] 12b inner surface [0069] 12-1 contact surface [0070] 12-19 guide face [0071] 19 piston [0072] 100 damper [0073] 110 damping space [0074] 111 first fluid chamber [0075] 112 second fluid chamber [0076] 300 method of manufacture [0077] 310 introduction [0078] 320 reworking [0079] 400 method of production [0080] 410 manufacturing [0081] 420 installing [0082] 430 selecting [0083] ALA longitudinal axis of the outer body [0084] B width [0085] B1 first width [0086] B2 second width [0087] E1 first end [0088] E2 second end [0089] F flow impedance [0090] F1 first flow impedance [0091] F2 second flow impedance [0092] H travel path [0093] K damping force [0094] K1 first damping force [0095] K2 second damping force [0096] LA longitudinal axis [0097] Q flow cross-section [0098] Q1 first flow cross-section [0099] Q2 second flow cross-section [0100] T depth [0101] T1 first depth [0102] T2 second depth