Storage with a gasbag, especially for a vibration damper

Abstract

Storage unit (13) with a gasbag (15; 17) i for a vibration damper (1), comprising a casing (19) arranged in a housing (3) and having several gasbag sections (15; 17; 15a; 15b; 15.1 - 15.5) by means of which the gasbag can be adapted to an outer housing wall of the storage unit (13) in its shape and / or position, wherein the storage unit (13) has at least one form-giving guide body (23; 25; 51; 53; 55) which supports two adjacent gasbag sections (15; 17; 15a; 15b; 15.1 - 15.5) relative to each other, characterized in that the guide body has at least two guide webs (53; 55) which are connected to each other via a support web (57), wherein the support web (57) is attached to the housing wall (3). supported and the guide web (53; 55) has a rolled-up end profile (59) at its end with respect to its radial extent.

Description

[0001] The invention relates to a vibration damper with a gas bag according to the preamble of claim 1.

[0002] From DE 198 35 222 A1, a vibration damper is known whose compensation chamber is pressurized by means of a gas bag. The gas bag preferably consists of a multi-layered casing material that is welded at the edges, thus forming a bag shape. One layer of the casing material is made of a metallic material. This layer is significantly more susceptible to creasing and wrinkling than the plastic layers.

[0003] To achieve a defined gasbag shape, axial connections are preferably used, dividing the gasbag into individual cushions. These axial connections are formed by welds. This allows the gasbag to be easily adapted to curved installation spaces in the area of ​​the connections.

[0004] In the execution according Fig. According to DE 198 35 222 A1, the gasbag is used in a monotube vibration damper. This means the gasbag only rests against the inner wall of the cylinder. If a large storage volume is required, one larger gasbag or several smaller ones would have to be used. An axially larger gasbag would result in poor space utilization. A radially larger gasbag would lead to excessive wrinkling, and multiple gasbags would drastically complicate installation.

[0005] DE 10 2007 058 544 A1 describes a pressure vessel that can also be used in combination with a vibration damper. In the design according to Fig. 2.5 Two gasbags are provided, separated from each other by a cylindrical element. The cylindrical element can provide support for the two gasbags.

[0006] A fundamentally similar structure is known from GB 974 702 A.

[0007] US patent 4,443,926 A discloses a gasbag which can comprise two chambers and is attached, for example, to a working cylinder of the vibration damper on the outside by means of a clamp.

[0008] US patent 3,945,663 A1 discloses a vibration damper that has two gas bags surrounding the working cylinder and also having a common overlap area.

[0009] US Patent 3,123,347 A describes a vibration damper with a gasbag that has axially extending separating ribs, which make it easier to deform the gasbag into a ring shape.

[0010] GB 615 860 A shows a vibration damper comprising two gasbags in an axial row arrangement. A separating disc is inserted between the two gasbags, thereby stabilizing the row arrangement.

[0011] The object of the present invention is to achieve the largest possible volume using a gasbag arrangement.

[0012] According to the invention, the problem is solved by the features of claim 1.

[0013] The major advantage of the invention is that the gasbag can be designed not only as a single layer, as is the case with prior art, but also as a multi-layered system. This allows for significantly better utilization of the storage volume. The guide body simplifies installation and forces the gasbag into a predetermined installation position.

[0014] This ensures that the predetermined installation shape is maintained even when installed in the storage tank. A predetermined installation position has the fundamental advantage that the load on the gasbag can be precisely predetermined, allowing the gasbag to be designed for the specific load case.

[0015] The connection of at least two guide ribs stiffens the entire gasbag assembly.

[0016] Furthermore, a specific bending radius can be defined between two adjacent gasbag sections.

[0017] In another solution, the guide body is formed by a longitudinally slotted tube with a C-shaped cross-section, the inner and / or outer diameter of which forms a guide surface. The longitudinal slot facilitates a spring action of the guide body towards the gasbag. The gasbag is arranged spirally within the guide body. The slot in the tube serves as a transition between the spiral sections.

[0018] The installation of a spiral gasbag is significantly simplified if the guide body has a radially outward-widening reducing ramp for forming the gasbag's spiral shape. The gasbag slides automatically into the next spiral section, as the ends of the gasbag cannot become jammed.

[0019] With regard to minimizing wrinkling, it is advantageous if the gasbag has a greater radial width in the radially outer area of ​​the storage than in the radially inner area of ​​the storage.

[0020] Especially in the case of a storage device in a vibration damper, it is advantageous if the guide body is made of a thermally conductive material, thus promoting heat dissipation from the vibration damper.

[0021] Optionally, the housing wall is formed by a tubular body that has a radial indentation, at least in some areas, which prevents the gasbag from rotating circumferentially. This ensures a constant width of the gasbag, particularly at its ends.

[0022] The following description of the figures will be used to explain the invention in more detail.

[0023] It shows: Fig. 1. Schematic diagram of a storage device in a vibration damper Fig. 2. Variation on Fig. 1 Fig. 3 - 6 sectional views of different gasbag designs

[0024] The Fig. Figure 1 shows, in a highly simplified form, a vibration damper 1 in the design of a single-tube vibration damper. However, the invention is not fundamentally limited to this design. A piston rod 5 with a piston 7 is guided axially within a cylinder 3, the piston 7 separating two working chambers 9; 11 filled with damping medium. Damping valves in the piston 7 are not shown. The vibration damper 1 has an accumulator 13, with the cylinder 3 forming the housing of the accumulator 13. In this case, the accumulator 13 comprises several gas bags 15; 17, which are formed by gas-filled envelopes 19. These envelopes 19 have two preferably multi-layered films, which are welded at the edges. For the specific construction, reference is made to DE 198 35 222 A1. The gas bags are arranged concentrically to each other in a ring shape, as shown in the figure. Fig. 3 is evident. Each gasbag 15; 17 has a filling port 21 through which gas can be introduced into the outer body 19.

[0025] The storage unit 13 further comprises at least one form-defining guide body 23; 25, which supports two adjacent gasbag sections relative to each other. In this embodiment, the guide body 23; 25 is formed by a tube, which is arranged, in particular, between the two gasbags 15, 17. The tube has a circumferentially closed profile. The outer gasbag 15 is also enclosed in a guide body 23, so that a defined spatial shape is provided for the gasbag, independent of the cylinder diameter. The outer guide body 23 also offers the advantage of a defined outer diameter, which in turn simplifies the installation of the gasbag 15 in the cylinder 3 of the vibration damper 1.

[0026] Both gasbags 15, 17 are fixed in a housing of the accumulator 13 and in the cylinder 3, respectively, by means of a retaining bridge 27. The retaining bridge 27 is formed by a disc that has several connections 29; 31 for receiving and filling the gasbags 15; 17. The working chamber 11, located away from the piston rod, is connected via an exemplary central opening 33 to a compensation chamber 35, also filled with damping medium, which extends between the retaining bridge 27 and the bottom of the cylinder 3. The area from the retaining bridge 27 to the bottom of the cylinder 3 forms a complete accumulator that could also be used independently of the cylinder or the vibration damper.

[0027] The retaining bridge 27 is connected to an inner wall 39 of the cylinder 3 via a positive locking connection 36, so that the gasbags 15; 17 cannot float in the damping medium, but always assume a defined position.

[0028] The Fig. Figure 2 shows a modification of the retaining bridge 27 for the gasbags 15 and 17. The connections 29 and 31 in the retaining bridge 27 are connected to a common filling channel system 37, which in turn is aligned with a filling opening 41 in the cylinder 3. The retaining bridge 27 is sealed at each end of its outer surface to the inner wall 39 of the cylinder 3 by ring seals 43. Gas can be introduced into the two shell bodies 19 via a filling device (not shown) through the filling opening 41 and the subsequent filling channel system. Once the intended filling pressure is reached, the filling opening 41 and / or the filling channel system 37 is sealed by a closure piece 45. In this example, the opening 33 between the working chamber 11 and the compensation chamber 35 in the retaining bridge is arranged eccentrically.

[0029] The Fig. Figure 4 shows a modification of the memory according to Fig. 3. In a different configuration, a single gasbag 15 is shown, which is also arranged in a tube as a guide body 25. In this configuration, the tube is designed with a longitudinal slot 47 and has a C-shaped cross-section. This allows the inner and outer diameters to form a guide surface for the gasbag 15, which is arranged spirally in the guide body 25. The longitudinal slot 47 forms the transition between an outer turn 15a and an inner turn 15b of the gasbag 15. In the circumferential direction, a radially outwardly widening reducing chamfer 49 of the guide body 25 separates one end of the gasbag 15 from the transition to the inner turn 15b, thus simplifying the spiral formation of the gasbag 15 during assembly. The reducing chamfer 49, together with the outer guide surface of the guide body 25, forms a funnel shape in the region of the longitudinal slot 47.

[0030] Optionally, another tubular guide body 51 can be arranged within the inner coil 15b of the gasbag 15. From the Fig. It can be further seen from Figure 4 that the gasbag 15 can have a greater width b in the radially outer area or outer coil 15a than in the radially inner area or inner coil 15b. This keeps the ratio of radius of curvature to gasbag width possibly constant, so that the wrinkling is also approximately comparable in all areas of the gasbag.

[0031] The Fig. 5 and Fig. Figure 6 shows a gasbag 15 with a meandering cross-section in a housing or cylinder 3. The guide body is designed as a web that is radially supported against the housing wall of the accumulator 13. In this embodiment, the guide body has at least two guide webs 53; 55, which are connected to each other via a support web 57, the support web 57 being supported against the housing wall. As can be seen from the Fig. 5 and Fig. As can be seen from Figure 6, the U-shaped design of the guide body offers the possibility of forming five gasbag sections 15.1 - 15.5 with two standardized guide bodies in an alternating arrangement.

[0032] The execution according Fig. 6 differs from the Fig. 5 by the fact that the guide web 53; 55 has a rolled-up end profile 59 at its end with respect to its radial extent. This results in a particularly kink-free transition between two gasbag sections 15.1 - 15.2.

[0033] Both in the Fig. 5 as in the Fig. 6 The tubular housing wall has a depression 61 in some areas, by means of which the gasbag 15 is secured against rotation in the circumferential direction. This depression 61 can also be found in the cylinder according to Fig. 1 or Fig. 2.

[0034] For all variants, it can be provided that the guide body is made of a thermally conductive material in order to promote heat dissipation also from the compensation chamber 35. Reference sign 1 vibration damper 3 cylinders 5 piston rod 7 pistons 9 workrooms 11 workrooms 13 storage locations 15 Gasbag 15a outer gasbag coil 15b inner gasbag coil 17 Gasbag 19 Enclosing bodies 21 Filling port 23 guide bodies 25 guide bodies 27 Halt bridge 29 connection 31 connection 33 Opening 35 compensation area 36 Positive locking connection 37 Filling channel system 39 Inner wall 41 Filling opening 43 Ring seal 45 locking piece 47 longitudinal slots 49 Reducing slope 51 Guide bodies 53 Guide bridge 55 Guide bridge 57 Support bridge 59 rolled end profile 61 Indentation

Claims

[1] Accumulator (13) with a gas bag (15; 17) for a vibration damper (1), comprising an enveloping body (19) which is arranged in a housing (3) and has a plurality of gas bag sections (15; 17; 15a; 15b; 15.1 - 15.5), via which the gas bag can be adapted to an outer housing wall of the accumulator (13) in its shape and / or position, wherein the accumulator (13) has at least one shape-forming guide body (23; 25; 51; 53; 55) which supports two adjacent gas bag sections (15; 17; 15a; 15b; 15.1 - 15.5) relative to one another, characterized by in that the guide body has at least two guide webs (53; 55) which are connected to one another via a support web (57), the support web (57) being supported on the housing wall (3) and the guide web (53; 55) having a rolled-up end profile (59) at its end with respect to its radial extent. [2] Accumulator (13) with a gas bag (15; 17) for a vibration damper (1), comprising an enveloping body (19) which is arranged in a housing (3) and has a plurality of gas bag sections (15; 17; 15a; 15b; 15.1 - 15.5), via which the gas bag can be adapted to an outer housing wall of the accumulator (13) in its shape and / or position, characterized by that the guide body (23) is designed as a longitudinally slotted tube with a C-shaped cross-section, the inner and / or outer diameter of which forms a guide surface and is arranged spirally in the guide body (23). [3] Memory according to claim 2, characterized by that the guide body (23) has a radially outwardly widened reducing bevel (49) for the spiral shape formation of the gas bag (15a; 15b). [4] Memory according to at least one of claims 1-3, characterized bythat the gas bag (15a) has a greater radial width in the radially outer region of the accumulator (13) than in the radially inner region (15b) of the accumulator (13). [5] Memory according to one of claims 1-4, characterized by that the guide body (23; 25; 51; 53; 55) consists of a thermally conductive material. [6] Memory according to one of claims 1-5, characterized by that the housing wall is formed by a tubular body (3) which has at least in some regions a radial indentation (61) by means of which the gas bag (15) is secured against rotation in the circumferential direction.

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