corrugated member

Abstract

The invention relates to a corrugated member for protecting an inside thereof which is variable in length in a working direction. It is formed of an elastic material, has as a basic shape a cylindrical jacket with a cylindrical axis corresponding to the working direction and a jacket surface which is elastic in the working direction and is shaped as a plurality of corrugation sections transverse to the working direction. The corrugation sections have a first corrugation diameter perpendicular to the working direction and a second corrugation diameter different from the first corrugation diameter spaced apart in the working direction and in turn a third corrugation diameter different from the second corrugation diameter spaced apart in the working direction, and a corrugation wall formed integrally thereof. Successive corrugation sections in the working direction have the same inner corrugation diameter but alternating outer corrugation diameters. The corrugation wall of the corrugation sections with the smaller second corrugation diameter is pre-shaped convex, i.e. curved outwards, and the corrugation wall of the adjacent corrugation sections with the larger third corrugation diameter is pre-shaped concave, i.e. curved inwards, at least in the overlapping region between the first and the second corrugation diameter.

Description

Technical Field

[0001] The present invention relates to a corrugated member (Faltenbalg) for protecting a component arranged inside the corrugated member and having a variable length in the working direction. Background Technology

[0002] Corrugated components are used as resilient protective walls, especially around parts of variable length, such as springs in motor vehicles. Corrugated components protect the springs from the penetration of dust and moisture, and also prevent direct contact with the spring's travel.

[0003] The corrugated member is formed of an elastic material (such as a rubber compound) and has a cylindrical sheath as its basic shape, which has a cylindrical axis corresponding to the working direction and a sheath surface.

[0004] The sheath surface is folded here, that is, formed into multiple folds that are substantially transverse to the working direction.

[0005] The corrugated portion has a first corrugated diameter perpendicular to the working direction, a second corrugated diameter spaced apart from the first corrugated diameter in the working direction, and another first corrugated diameter spaced apart from the second corrugated diameter in the working direction, and corrugated walls integrally formed therefrom. In the non-operating position, the two corrugated walls are therefore at an angle defined by the distance between the corrugated diameters, and thus each corrugated portion can be expanded or compressed. The corrugated member is therefore designed to have high elasticity in the working direction corresponding to the expansion or closure of the corrugated portions.

[0006] The corrugated walls here are typically designed as straight surfaces or pre-formed in a curved manner to achieve, for example, a preferred orientation or defined force application. If the corrugated members are subjected to very large compression or additional loads due to rotation of internal components or centrifugal force, the corrugated walls may come into contact with each other and may adhere or bond to each other. Summary of the Invention

[0007] Therefore, the object of the present invention is to provide an improved solution for a corrugated member in which such risk is further minimized, and thus the corrugated member can be permitted even for high compression.

[0008] This objective is achieved by a corrugated member having the features described below. The corrugated member protects a component disposed inside it and whose length is variable in the working direction. The corrugated member is formed of an elastic material and has a cylindrical sheath as its basic shape, the sheath having a cylindrical axis corresponding to the working direction, and a sheath surface shaped as a plurality of pleats transverse to the working direction and thus elastic in the working direction. Each pleat has a first pleat diameter perpendicular to the working direction and a second pleat diameter spaced apart from the first pleat diameter in the working direction, and further a first pleat diameter spaced apart from the second pleat diameter in the working direction, and a pleated wall integrally formed therefrom. Advantageous improvements can also be derived below.

[0009] Therefore, according to the present invention, continuous folded portions in the working direction are provided, each having the same inner fold diameter but different outer fold diameters, and matching each other in shape.

[0010] In addition to the second fold diameter of the folded portion, at least one adjacent folded portion is provided with a third outer fold diameter that is larger than the second fold diameter. Whether the outermost folded portion of the corrugated member as a whole begins or ends on the outside with a folded portion having the second fold diameter or a folded portion having the third fold diameter is irrelevant to the function; that is, what matters is the sequence of at least two folded portions optimized relative to each other in this way.

[0011] The fold wall of a fold portion with a smaller second fold diameter is preformed to be convex, that is, curved outward.

[0012] In contrast, the folded walls of adjacent folds with a larger third fold diameter are pre-formed to be recessed, i.e., bent inwards, at least in the overlapping area between the inner first and second fold diameters. The two folded walls are preferably formed in such a way that, even under maximum compression, the convex folded walls remain non-contacting, or at most have point contact. Therefore, adhesion or bonding of the folded walls can be prevented even under maximum compression and potential rotational loads on the corrugated member.

[0013] In a particularly preferred improvement, the fold wall of the fold portion having a larger third fold diameter is then preformed as convex, that is, outwardly curved, in the outer region between the second and third fold diameters (i.e., outside the overlapping region of the first and second folds). Attached Figure Description

[0014] The invention will now be described in more detail below with reference to exemplary embodiments and the accompanying drawings, in which:

[0015] Figure 1 An overall view of the corrugated member according to the invention, viewed from the outside, is shown.

[0016] Figure 2 It shows the source based on Figure 1 Details of the sheath area,

[0017] Figure 3 The wall of the corrugated member is shown according to Figure 2 A magnified view of the details under no-load conditions.

[0018] Figure 4 The image shows details of the sheath area taken from the corrugated member under maximum compression.

[0019] Figure 5 The uncompressed corrugated component is shown.

[0020] Figure 6 The data under maximum compression is shown. Figure 5 Corrugated components. Detailed Implementation

[0021] Figure 1 A corrugated member is shown, which is used, for example, to protect a component (not shown here) arranged inside the corrugated member and having a variable length in the working direction (Z).

[0022] The corrugated component is made of an elastic material, such as a rubber compound. The corrugated component has a cylindrical sheath as its basic shape, which has a cylindrical axis D0 corresponding to the working direction Z and sheath surfaces arranged rotationally symmetrically with respect to the cylindrical axis.

[0023] In principle, for corrugated components, the sheath surface is typically shaped into multiple pleats 10, 20 that are transverse to the working direction Z, and is therefore elastic in the working direction Z.

[0024] Each pleated portion 10 or 20 has a circular cross-sectional area, a first pleated diameter perpendicular to the working direction Z, a second pleated diameter spaced apart from the first pleated diameter in the working direction and different from the first pleated diameter, and another first pleated diameter spaced apart from the second pleated diameter in the working direction, and thus forming a pleated wall.

[0025] However, the corrugated member proposed here differs from the structural forms previously known from the prior art in two fundamental details: firstly, the corresponding outer fold diameters D2 and D3 are used alternately for the continuous fold portion; secondly, the shape of the fold wall is concave or convex in a manner that coordinates with each other, so that the fold wall can still easily match its shape without surface contact, even under maximum compression.

[0026] Therefore, the continuous corrugated portions 10 and 20 in the working direction Z each have the same inner corrugation diameter D1, but different outer corrugation diameters D2 and D3. That is, in addition to the second corrugation diameter D2 at the corrugated portion 10, at least one adjacent corrugated portion 20 is also provided with a third outer corrugation diameter D3 that is larger than the second corrugation diameter. It is not important here which outer corrugation diameter or which corrugation type terminates at the outer end of the corrugated member in each case.

[0027] The folded walls 13 of the folded portion 10, which has a smaller second fold diameter D2, are each pre-formed as convex, i.e., outwardly curved, as if already formed from... Figure 2 It can be seen from the middle, but from Figure 3 This can be better seen in the diagram. Therefore, the pleated wall 13 is specifically shown as a protrusion, i.e., an outwardly curved shape, on the direct connecting line H13 (shown only in a simplified diagram for clarity). The connecting line H13 depicts an imaginary linear connection between the inner point 11 corresponding to the pleated diameter D1 and the point 14 of the second outer pleated diameter.

[0028] In contrast, the fold wall 23 of the adjacent fold portion 20 has a larger third fold diameter D3 at point 25 on the outer side, and is pre-formed to be concave, i.e., curved inward, at least in the overlapping region (i.e., between the inner first fold diameter and the second fold diameter, or between point 24, the middle of the inner point 12 and the point corresponding to the second fold diameter D2). This can be further illustrated with reference to the connecting line H23 inserted in simplified form. Furthermore, the exemplary embodiments selected herein each show a preferred improvement, according to which the fold wall 26 of the fold portion 20 with the larger third fold diameter D3 is pre-formed to be convex, i.e., curved outward, in the outer region (i.e., between the second fold diameter D2 and the third fold diameter D3, or between points 24 and 25).

[0029] However, in Figure 4 As can be seen, when the corrugated member is under maximum compression, the corrugated wall 13 of the corrugated part 10, which is convexly bent outward, and the corrugated wall 23 of the corrugated part 20, which is concavely bent inward, have mutually coordinated shapes. However, due to the bulging of the concavely bent inward of the corrugated part 20, the corrugated part 10 still does not come into surface contact with the corrugated part 20.

[0030] Therefore, it is possible to realize the corrugated component from the position according to Figure 5 The maximum compression of the extension range Z0 in the non-operating position to the extension range ZF under the action of the force F in the working direction X, which is significantly greater than 50%, preferably about 75%.

Claims

1. A corrugated member for protecting a component disposed inside the corrugated member and having a variable length in the working direction (Z), The corrugated member is formed of an elastic material and has a cylindrical sheath as its basic shape. The cylindrical sheath has a cylindrical axis (D0) corresponding to the working direction, and a sheath surface that is shaped into a plurality of pleats (10, 20) transverse to the working direction (Z) and is therefore elastic in the working direction (Z). Each pleated portion (10, 20) has a first pleated diameter perpendicular to the working direction (Z) (X, Y), a second pleated diameter spaced apart from the first pleated diameter in the working direction, and further a first pleated diameter spaced apart from the second pleated diameter in the working direction. The folded wall formed by this whole Its features are, The continuous folded portions (10, 20) in the working direction (Z) each have the same inner folded diameter (D1), but different outer folded diameters (D2, D3). That is, in addition to the second folded diameter (D2), at least one adjacent folded portion (20) is also provided with a third folded diameter (D3) that is larger than the second folded diameter. The folded wall (13) of the folded portion (10) with a smaller second fold diameter (D2) is preformed as convex, that is, curved outward, in its respective case. The fold wall (23) of the adjacent fold portion (20) with a larger third fold diameter (D3) is preformed to be concave, that is, bent inward, at least in the overlapping area (D1-D2) between the inner fold diameter and the second fold diameter.

2. The corrugated member as claimed in claim 1, wherein, The fold wall (26) of the fold portion (20) with a larger third fold diameter (D3) is preformed as convex in the outer region (D2-D3) between the second fold diameter and the third fold diameter, that is, bent outward.

3. Use of the corrugated member as described in any of the preceding claims for use in pneumatic springs of motor vehicles.

4. The use as described in claim 3, wherein, The pneumatic spring is a pneumatic spring used in the suspension of the steerable wheels of a motor vehicle.

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