Shock absorber, piston rod and method for fixing working piston on piston rod

Abstract

The invention discloses a shock absorber, a piston rod and a method for fixing a working piston on the piston rod. A shock absorber for a vehicle includes a damper tube at least partially filled with a damping liquid, a piston rod movable back and forth in the damper tube, and a working piston movable together with the piston rod, by which an inner space of the damper tube is divided into a piston rod-side working space and a working space remote from the piston rod, the shock absorber has at least one wedge element and at least one support element, and the piston rod has at least one wedge element recess for partially receiving the at least one wedge element, in which the at least one wedge element is arranged in a supported state, the at least one support element is connected to the working piston in such a way that the at least one support element supports the working piston relative to the piston rod by means of the at least one wedge element arranged in the at least one wedge element recess.

Description

[0001] This application is a divisional application of Chinese invention patent application No. 201810975553.7, filed on August 24, 2018, entitled "Shock absorber, piston rod and method for fixing a working piston on a piston rod". Technical Field

[0002] The invention relates to a shock absorber for a vehicle, a piston rod and a method for fastening a working piston to a piston rod of a shock absorber. Background Art

[0003] Shock absorbers of this design are known in numerous embodiments from the prior art.

[0004] DE 101 38 322 A1 has disclosed a shock absorber having a working piston which is attached to a piston rod by a threaded connection.

[0005] In the case of the embodiments known from the prior art, the problem is that, due to the required strength and continuous load performance, weight and material savings for the piston rod part and its working piston attachment are not possible or are possible only to a very limited extent. In particular, high component weights are associated with lower shock absorber performance and higher costs (such as material and / or processing costs).

[0006] The object of the present invention is therefore to provide an improved shock absorber and piston rod which avoid the above-mentioned disadvantages. In particular, an improved piston rod is provided by the improved shock absorber, which improved piston rod arrangement allows a secure and as stress-free as possible attachment to the working piston with the same or lower component weight and improved shock absorber performance, while maintaining the same or lower component weight. In addition, a simple, less error-prone, more secure method for fixing the working piston to the piston rod of the shock absorber is provided. In addition, a method with low manufacturing costs is provided. Summary of the invention

[0007] This object is achieved by means of a shock absorber according to the invention, a piston rod according to the invention and a method according to the invention for fastening a working piston to a piston rod of a shock absorber.

[0008] The subject of the present invention is a shock absorber for a vehicle, which includes a damping tube, which is at least partially filled with a damping fluid, a piston rod capable of moving back and forth in the damping tube, and a working piston capable of moving together with the piston rod, the inner space of the damping tube being divided into a piston rod side working space and a working space away from the piston rod by the working piston, the shock absorber having at least one wedge element and at least one supporting element, and the piston rod having at least one wedge element groove for partially receiving the at least one wedge element, the at least one wedge element being arranged in the at least one wedge element groove in a supported state, and the at least one supporting element being connected to the working piston in such a way that the at least one supporting element supports the working piston relative to the piston rod by means of the at least one wedge element arranged in the at least one wedge element groove.

[0009] A further subject matter of the invention is a piston rod for a shock absorber according to the invention, which piston rod has at least one wedge element recess for partially receiving at least one wedge element according to the invention.

[0010] Another subject matter of the present invention is a method for fastening a working piston to a piston rod of a shock absorber according to the invention, in particular for a vehicle, comprising the following steps:

[0011] a) providing at least one wedge-shaped element,

[0012] b) providing at least one supporting element,

[0013] c) providing a piston rod having at least one wedge element groove for partially receiving the at least one wedge element provided in step a),

[0014] d) providing a working piston having at least one passage opening for guiding through the piston rod provided in step c),

[0015] e) introducing the piston rod provided in step d) through the passage opening of the working piston provided in step d) and arranging the working piston on the side of at least one wedge element groove of the introduced piston rod, axially to the piston rod, the working piston being arranged in such a way that the working piston does not cover the wedge element groove,

[0016] f) arranging the at least one wedge element provided in step a) in the at least one wedge element groove of the piston rod introduced in step e),

[0017] g) arranging the at least one supporting element provided in step b) on the other side of the at least one wedge-shaped element groove of the piston rod (3) introduced in step e), the other side being axially relative to the piston rod, and

[0018] h) supporting the supporting element arranged in step g) via the working piston arranged in step e) via at least one wedge element arranged in step f) relative to the piston rod introduced in step e) in at least one wedge element groove of the piston rod (3) introduced in step e).

[0019] The invention can be embodied as a shock absorber, a piston rod and a method for fastening a working piston to a piston rod of a shock absorber.

[0020] Compared to conventional shock absorbers, the shock absorber according to the invention has the advantage of lower component weight, in particular a lower weight of the piston rod at the same or increased strength and continuous load performance. In addition, a secure attachment to the working piston that is as stress-free as possible can be achieved at the same or lower component weight. In addition, in the event of an overload of the piston rod according to the invention, the latter is more inclined to bend than to break. In addition, there is the possibility of increasing the size of the working piston area for a shock absorber of the same or reduced size. In addition, the reduced piston rod diameter of the piston rod according to the invention is associated with less friction due to the smaller contact area. In addition, the production cost of the piston rod is lower.

[0021] Compared with conventional piston rods, the piston rod according to the present invention has the advantage of lower piston rod weight while maintaining the same or improved strength and continuous load performance. In addition, the manufacturing cost of the piston rod is lower.

[0022] Compared with conventional methods, the method according to the present invention for fixing a working piston on a piston rod of a shock absorber, in particular for a vehicle, has the advantages of being simpler and more secure.

[0023] In the context of the present invention, support is understood to mean, in particular, at least a non-positive connection which fastens the working piston to the piston rod, which fastening can be released again and / or adjusted. This connection is also presented by way of example as a positive connection.

[0024] In another embodiment of the present invention, at least one wedge-shaped element groove for receiving at least one wedge-shaped element cooperates with the at least one wedge-shaped element in a supported state.

[0025] In the context of the present invention, a fit is understood to mean at least a transition fit, in particular an interference fit. For example, two wedge-shaped elements are used.

[0026] According to another embodiment of the invention, at least one wedge-shaped element groove for receiving the at least one wedge-shaped element and a side of the at least one wedge-shaped element to be received in the at least one wedge-shaped element groove have at least one geometrically concave shape.

[0027] According to another embodiment of the invention, on the side facing the piston rod, at least one wedge-shaped element has at least one geometrically convex shape for being received in at least one concave shape of a wedge-shaped element groove.

[0028] According to another embodiment of the present invention, at least one wedge-shaped element is configured as a geometric hollow conical segment, and at least one supporting element is configured as a geometric funnel shape, and the geometric hollow conical segment of at least one wedge-shaped element is arranged in a supported state in the geometric funnel shape of the supporting element and is configured as a clamping fit.

[0029] According to another embodiment of the invention, the at least one wedge element is selected from the group consisting of a collet, a wedge, a clamping bushing, a jaw, a chuck, a clamping sleeve, a half shell or a combination thereof.

[0030] According to another embodiment of the invention, at least one supporting element is selected from the group comprising a collet nut, a threaded nut, in particular an externally threaded nut, a threaded liner, a liner with an external thread, a counter washer, a stop nut, a locking nut or a combination thereof.

[0031] In another embodiment of the present invention, the order of steps a) to d) is arbitrary. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The shock absorber according to the invention and the piston rod according to the invention will be described using the accompanying drawings, in which:

[0033] Figure 1 The longitudinal section of a shock absorber according to one exemplary embodiment of the invention is schematically shown in the supported state in the region of the working piston. DETAILED DESCRIPTION

[0034] Figure 11 is a longitudinal section along the longitudinal axis L (illustrated using dashed lines) of a shock absorber 1 according to one embodiment of the invention having a damping tube 2, a piston rod 3 and a working piston 4 arranged on the piston rod 3 in the region of a working piston 4. The working piston 4 divides the interior space of the damping tube 2 into a piston rod-side working space 5 and a working space 6 remote from the piston rod. The piston rod 3 has at least one wedge element groove (shown as two wedge element grooves 9, 9') for partially receiving at least one wedge element (shown as two wedge elements 7, 7'). In the supported state shown, the wedge elements 7, 7' are arranged in the wedge element grooves 9, 9', and at least one support element 8 is connected to the working piston 4 in such a way that the at least one support element 8 supports the working piston 4 relative to the piston rod 3 via the wedge elements 7, 7' arranged in the wedge element grooves 9, 9'. In the exemplary embodiment shown, for the purpose of support, a support element 8 with an external thread is screwed into an internal thread that matches the external thread and is arranged in the working piston 4. As the screwing action increases, the working piston 4 is supported more firmly relative to the piston rod 3 by the wedging action between the geometric funnel shape of the support element shown and the wedge elements 7, 7' arranged in the wedge element grooves 9, 9'.

[0035] Industrial Applicability

[0036] Shock absorbers, piston rods and methods for fastening a working piston to a piston rod of a shock absorber of the type described above are used in the production of vehicles, in particular chassis of motor vehicles, motorcycles, bicycles, snowmobiles and electric vehicles.

[0037] Reference numerals list

[0038] 1 Shock absorber

[0039] 2 Damping tube

[0040] 3 Piston rod

[0041] 4 Working piston

[0042] 5 Working space on piston rod side

[0043] 6 Working space away from piston rod

[0044] 7, 7' wedge element

[0045] 8 Support elements

[0046] 9, 9' wedge-shaped element groove

[0047] L Longitudinal axis of the shock absorber

Claims

1. A shock absorber (1) for a vehicle, comprising: A damping tube (2) is at least partially filled with a damping fluid, a piston rod (3) can move back and forth in the damping tube (2), a working piston (4) can also move together with the piston rod (3), and the internal space of the damping tube (2) is divided into a piston rod side working space (5) and a working space (6) away from the piston rod by the working piston (4), It is characterized in that The shock absorber (1) has at least one wedge element (7, 7') and at least one supporting element (8), and the piston rod (3) has at least one wedge element groove (9, 9') for partially receiving the at least one wedge element (7, 7'), the at least one wedge element (7, 7') being arranged in the at least one wedge element groove (9, 9') in a supported state, and the at least one wedge element groove (9, 9') having a geometrically concave shape so that the piston rod has a reduced piston rod diameter; and the at least one supporting element (8) is connected to the working piston (4) in such a way that the at least one supporting element (8) supports the working piston (4) relative to the piston rod (3) via the at least one wedge-shaped element (7, 7') arranged in the at least one wedge-shaped element recess (9, 9'); The outer diameter of the at least one wedge-shaped element (7, 7') increases from the working space (6) away from the piston rod to the working space (5) on the piston rod side; The working piston (4) does not cover the wedge-shaped element recess (9, 9').

2. The shock absorber (1) according to claim 1, characterized in that The at least one wedge-shaped element groove (9, 9') for receiving the at least one wedge-shaped element (7, 7') cooperates with the at least one wedge-shaped element (7, 7') in a supported state.

3. The shock absorber (1) according to claim 1 or 2, characterized in that: The at least one wedge-shaped element groove (9, 9') for receiving the at least one wedge-shaped element (7, 7') and the side of the at least one wedge-shaped element (7, 7') to be received in the at least one wedge-shaped element groove (9, 9') have at least one geometric concave shape.

4. The shock absorber (1) according to claim 3, characterized in that On the side facing the piston rod, the at least one wedge-shaped element (7, 7') has at least one geometrically convex shape for being received in the at least one concave shape of the wedge-shaped element groove (9, 9').

5. The shock absorber (1) according to any one of claims 1 to 2, characterized in that The at least one wedge-shaped element (7, 7') is configured as a geometric hollow conical segment, and the at least one supporting element (8) is configured as a geometric funnel shape, and the geometric hollow conical segment of the at least one wedge-shaped element (7, 7') is arranged in a supported state in the geometric funnel shape of the supporting element (8) and is configured as a clamping fit.

6. The shock absorber (1) according to any one of claims 1 to 2, characterized in that The at least one wedge-shaped element (7, 7') is selected from the group consisting of a collet, a wedge, a clamping bushing, a jaw, a chuck, a clamping sleeve, a half shell or a combination thereof.

7. The shock absorber (1) according to any one of claims 1 to 2, characterized in that The at least one supporting element (8) is selected from the group consisting of a collet nut, an externally threaded nut, a liner with an external thread, a stop nut, a locking nut or a combination thereof.

8. A piston rod (3) for a shock absorber (1) according to any one of claims 1 to 7, characterized in that: The piston rod (3) has at least one wedge element recess (9, 9') for partially receiving at least one wedge element (7, 7') according to any one of claims 1 to 7.

9. A method for fastening a working piston (4) to a piston rod (3) of a shock absorber (1), in particular for a vehicle, according to any one of claims 1 to 7, the method comprising the following steps: a) providing at least one wedge-shaped element (7, 7'), b) providing at least one supporting element (8), c) providing a piston rod (3) having at least one wedge-shaped element groove (9, 9') for partially receiving the at least one wedge-shaped element (7, 7') provided in step a), d) providing a working piston (4) having at least one passage opening for guiding through the piston rod (3) provided in step c), e) introducing the piston rod (3) provided in step c) through the passage opening of the working piston (4) provided in step d) and arranging the working piston (4) on the side of the at least one wedge-shaped element groove (9, 9') of the introduced piston rod (3) axially to the piston rod (3), the working piston (4) being arranged in such a way that the working piston (4) does not cover the wedge-shaped element groove (9, 9'), f) arranging the at least one wedge-shaped element (7, 7') provided in step a) in the at least one wedge-shaped element groove (9, 9') of the piston rod (3) introduced in step e), g) arranging the at least one supporting element (8) provided in step b) on the other side of the at least one wedge-shaped element groove (9, 9') of the piston rod (3) introduced in step e), axially to the piston rod (3), and h) supporting the supporting element (8) arranged in step g) via the working piston (4) arranged in step e) via the at least one wedge element (7, 7') arranged in step f) in the at least one wedge element groove (9, 9') of the piston rod (3) introduced in step e).

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