Device with a spring body made of elastomer material and a bearing bushing formed in the spring body

Abstract

Device (1) comprising: - a spring body (2) made of elastomer material (3) and - a bearing bushing (4) formed in the spring body (2), extending along a bushing axis (6) and open at its axial ends (7, 8), - wherein a free passage cross-section (9) of the bearing bushing (4) is bounded by elastomer material (3) around the bushing axis (6), - wherein a stiffening structure (10) is arranged around the bushing axis (6) at one of the axial ends (7, 8) of the bearing bushing (4) and embedded in the elastomer material (3), - wherein at one axial end (7) the stiffening structure (10) encloses a virtual circle (21) around the bushing axis (6) with its inner circumference (12) and is elastically expandable away from the bushing axis (6) by a diameter (11) of the virtual circle enclosed by its inner circumference (12). to enlarge the circle (21), characterized by,- that at one axial end (7) of the bearing bushing (4) the circumferential length of the inner circumference (12) of the unexpanded stiffening structure (10) around the bushing axis (6) is at least 3.5 times as long as the diameter (11) of the virtual circle (21) enclosed by the inner circumference (12) around the bushing axis (6) and - that the stiffening structure (10) extends towards the other axial end (8) of the bearing bushing (4), the diameter (11) of the virtual circle (20) enclosed by its inner circumference (12) increasing towards the other axial end (8) of the bearing bushing (4).

Description

TECHNICAL FIELD OF THE INVENTIONThe invention relates to a device having a spring body made of elastomer material and a bearing bush formed in the spring body and extending along a bush axis and open at its two axial ends, wherein a free passage cross section of the bearing bush around the bush axis is bounded by elastomer material, wherein a stiffening structure is arranged around the bush axis at one of the axial ends of the bearing bush and is embedded in the elastomer material, wherein the stiffening structure encloses a virtual circle around the bush axis with its inner circumference and can be elastically expanded away from the bush axis in order to increase a diameter of the virtual circle enclosed by its inner circumference.The bearing bush is provided for receiving a bearing bolt which has a shank adapted to the free passage cross section of the bearing bush and a head projecting radially beyond the shank. In the mounted state, the bearing bolt protrudes with its head over the one axial end of the bearing bush and the bearing bolt is supported with its head on the bearing bush reinforced by the reinforcing structure. This prevents the bearing bolt from being pulled out of the bearing bush. In order nevertheless to enable simple insertion of the bearing bolt with the head first into the bearing bush, the stiffening structure can be elastically expanded away from the bush axis. The stiffening structure thus allows the head of the bearing bolt to pass through the bearing bush, but returns behind the head into its initial shape which is too narrow for this passage.The further configuration of the spring body made of elastomer material can be very different. The spring body can be, for example, annular, disk-shaped, wave-shaped or bell-shaped or have one or more spring arms.PRIOR ARTAn apparatus having the above features, which correspond to the preamble of independent claim 1, is known from DE 10 2019 000 970 B4. An elastomer element has a connection recess into which a widened end region of a retaining element can be linked, so that a connection region of the elastomer element defining the connection recess intersects the widened end region of the retaining element at least in sections in a linking-in direction. A stiffening structure stiffens the connection region of the elastomer element in order to make it more difficult for the widened end region of the retaining element to be disconnected. The stiffening structure is a stiffening sleeve which is arranged around the connection recess and which has a longitudinal slot which is open at least in a front end of the stiffening sleeve in the attachment direction. The stiffening structure can be configured annularly, hollow cylindrically or substantially hollow frusto-conical, wherein a combination of annular shape, hollow cylindrically shape and hollow frusto-conical shape is also possible. The stiffening structure can be one or more parts. As a result of the one or more slots, the stiffening structure has an elasticity in the radial direction, that is to say orthogonally to the tying-in direction, such that the retaining element can be more easily tied into the elastomer element. The stiffening structure can taper in the attachment direction of the holding element, so that after the attachment of the holding element, the widened end region is undercut by the stiffening structure in the attachment direction. The stiffening structure is encapsulated by the elastomer element by injection molding or vulcanized therein. The region of the elastomer element adjoining the connection receptacle can be provided with one or more grooves, for example, approximately V-shaped or U-shaped depressions, which extend along the tying-in direction. As a result, additional space for elastic deformation of the elastomer element can be provided. The stiffening structure can consist of a plastic, such as a thermosetting plastic or thermoplastic, or of metal. The stiffening structure is arranged in the connection region of the elastomer element so as to surround the connection recess at least in sections.In the device known from DE 10 2019 000 970 B4, the longitudinal slot in the stiffening structure has proven to be disadvantageous because the entire radial expansion of the stiffening structure is thereby converted into an expansion stress of the elastomer material in the region of the longitudinal slot when the retaining element is coupled in. This is associated with a considerable risk of crack formation in the elastomer element in the region of the longitudinal slot.In addition, the formation of a stiffening structure, which is at least partially frustoconical, as is preferred in DE 10 2019 000 970 B4, at least from metal is comparatively complicated and therefore costly.DE 198 05 401 C2 discloses an elastomer spring with a bushing for receiving a bearing bolt. The elastomer spring has a base body forming spring arms and the bushing for receiving the bearing bolt to be supported by the elastomer spring within the base body. The base body is formed integrally with the bushing using elastomer material. Between the bushing and the base body, a band-shaped force transmission ring surrounding the bushing is provided. The force transmission ring is more rigid in cross section than the base body, and the base body is more rigid in cross section than the bushing, so that the bushing acts like a first soft spring, which is connected upstream of the second harder spring of the base body with respect to the bearing bolt. The force transmission ring has apertures and may be an open ring. The force transmission ring is made of hard plastic or metal. The bushing has radially extending recesses, starting from a central passage region, in the elastomer material forming it.DE 199 46 238 C2 discloses an elastic slide bearing having a spring body made of elastomer material and having a slide bushing having a longitudinal axis. The sliding bushing lines a through opening in the spring body provided for receiving a bearing bolt that is displaceable in the direction of the longitudinal axis. When the slide bearing is used, the slide bushing receiving the bearing bolt exerts a compressive prestress on the region of the spring body adjoining it. No chemical bond is present between the sliding bushing and the spring body. Rather, the sliding bushing is undersize with respect to the diameter of the bearing bolt before the bearing bolt is introduced, so that the prestress exerted by the sliding bushing on the adjacent regions of the spring body is increased by introducing the bearing bolt. The slide bushing is wound from a flexible tape material. The sliding bushing has a polygonal or star-shaped free cross section.DE 43 24 000 A1 discloses an elastic slide bearing having a central through opening for receiving a bearing bolt which is round in cross section. The inner surface of the through-opening is formed by a sleeve arranged in a spring body made of elastic material. The central through-opening has a polygonal or star-shaped cross-section. The sleeve is made of a flexible, abrasion-resistant and temperature-stable plastic, in particular polytetrafluoroethylene (PTFE).DE 199 06 548 C1 discloses an elastic bearing for suspending a dynamically stressed functional part, for example the exhaust system of a motor vehicle. The elastic bearing has a loop made of a shaped body made of bent spring steel, the ends of which are permanently connected to one another, and two bushes, which are arranged in the loop and are supported on the shaped body made of spring steel, for a supporting and a fastening element to be supported. Damper arms made of an elastomer material are also provided, which engage the molded body in two regions spaced apart from one another, the distance between these regions changing when relative movements occur between the supporting and the fastening element to be supported. The elastomer material is vulcanized onto the molded body made of bent spring steel and completely covers the latter in order to form a corrosion protection layer.DE 10 2010 052 718 A1 discloses a storage device for a vehicle exhaust system having a fastening device for mounting the storage device on the vehicle side and a fastening device for mounting the storage device on the exhaust gas side. A damping body extends between the fastening devices. The damping body has two curved damping arms which abut each other to achieve a progressive damping characteristic as a result of a compressive load, with an increase in their curvature. The damping body has a reinforcing insert in the form of a textile insert. The textile insert extends along the bulges of the damping arms as well as around the circumference of openings of the fastening devices in the damping body. The textile insert serves to reinforce the bearing device, in particular in the transverse direction. Even if tensile loads act on the bearing device during operation of the vehicle, the reinforcing insert increases the rigidity since it has a very high rigidity during stretching.OBJECT OF THE INVENTIONThe invention is based on the object of providing a device with a spring body made of elastomer material and an open bearing bush formed in the spring body, into which bearing bush a bearing bolt with a projecting head can be inserted with limited insertion resistance without locally heavy stressing of the elastomer material, and which nevertheless secures the bearing bolt with a high extraction resistance in the bearing bush.SOLUTIONThe object of the invention is achieved by a device having the features of independent claim 1. Preferred embodiments of the device according to the invention are defined in the dependent claims.DESCRIPTION OF THE INVENTIONIn a device according to the invention with a spring body made of elastomer material and a bearing bush formed in the spring body and extending along a bush axis and open at its axial ends, a free passage cross section of the bearing bush around the bush axis is bounded by elastomer material. At one of the axial ends of the bearing bush, a stiffening structure is arranged around the bush axis and embedded in the elastomer material. The reinforcing structure encloses a virtual circle around the bushing axis with its inner circumference and is elastically expandable away from the bushing axis in order to increase a diameter of the virtual circle enclosed by its inner circumference. A circumferential length of the inner periphery of the non-widened stiffening structure about the bushing axis is for this purpose at least 3.5 times as long as a diameter of the virtual circle enclosed by the inner periphery about the bushing axis.In the device according to the invention, the stiffening structure is arranged around the bushing axis at least at one of the axial ends of the bearing bushing. The stiffening structure extends from there as far as the other of the two axial ends of the bearing bush. At least at one of the axial ends of the bearing bush, the inner circumference of the stiffening structure deviates considerably from a circle around the bush axis. This is defined in that the circumferential length of the inner periphery is not only π times as long, but at least 3.5 times as long as the diameter of the virtual circle enclosed by the inner periphery around the bush axis. The virtual circle enclosed by the inner circumference is the largest circle around the bushing axis, which touches the inner circumference of the stiffening structure, but does not intersect or exceed it. In the device according to the invention, the stiffening structure can be elastically expanded in that its inner circumference is deformed in the direction of a circle, as a result of which the diameter of the virtual circle enclosed by the inner circumference can increase by more than 10%.Before preferred embodiments of the device according to the invention are explained below, it should be pointed out that the statements made at the beginning under the heading "TECHNICAL FIELD OF THE INVENTION" apply completely to the device according to the invention and are therefore expressly also made to the device according to the invention.The inner periphery of the stiffening structure at the one axial end of the bearing bush preferably deviates from a circle in such a way that the circumferential length of the inner periphery of the non-widened stiffening structure about the bush axis is at least 4 times, preferably at least 5 times and even more preferably at least 6 times as long as the diameter of the virtual circle enclosed by the inner periphery. The more the circumferential length of the inner periphery exceeds π times the minimum free diameter, the greater the potential for increasing the diameter of the virtual circle enclosed by the inner periphery by deforming the inner periphery of the reinforcing structure toward a circle.Specifically, the inner periphery of the stiffening structure at the one axial end of the bearing bush can be oval, three-, four-, five- or hexagonal, rounded three-, four-, five- or hexagonal, star-shaped or rounded star-shaped. With a higher polygon than hexagonal, the excess of the circumferential length decreases more and more compared to π times the diameter of the virtual circle enclosed by the inner circumference. The opposite is true for a star-shaped inner periphery. Here, as the number of serrations increases, the excess of the circumferential length over π times the diameter of the virtual circle encircled by the inner circumference increases.Preferably, the stiffening structure extends around the bushing axis closed at the one axial end of the bearing bushing, i.e. it has no interruptions, in particular no longitudinal slots, there. However, the stiffening structure can also then have openings closed at the edges, in order, for example, to improve its embedding and integration into the elastomer material of the spring body.It has already been mentioned that the stiffening structure extends towards the other axial end of the bearing bush. In this case, the diameter of the virtual circle enclosed by the inner periphery of the stiffening structure increases towards the other axial end of the bearing bush. This can be achieved in particular by the inner periphery of the stiffening structure approaching the circular shape towards the other axial end of the bearing bush. In this case, the circumferential length of the stiffening structure between the two axial ends of the bearing bush preferably remains constant. The diameter of the virtual circle enclosed by the inner circumference of the stiffening structure, which diameter increases from one end to the other end, then results exclusively from the fact that it is maximum in the case of a circular shape of the inner circumference and any deviation of the inner circumference from the circular shape is reduced. The stiffening structure can thus be produced from a tubular section in the form of a cylindrical jacket section by the tubular section being deformed or compressed at its one end, which is then arranged in the region of the one axial end of the bearing bush. In the simplest case, it is compressed from two opposite directions into an oval shape. In this way, the stiffening structure can be brought in a simple manner from a simple and cost-effective basic shape into the shape which it has in the device according to the invention.The stiffening structure may also have a plurality of planar plates which are arranged consecutively along its inner periphery. These plates are connected to one another by the elastomer material of the spring body to form the elastically expandable stiffening structure. Due to the configuration of planar platelets, the inner periphery of the stiffening structure also here clearly deviates from a circular shape.The flat plates can be set at an angle to the bushing axis of the bearing bushing, namely in such a way that they extend away from the bushing axis from one of the axial ends to the other of the axial ends of the bearing bushing and thus form an inlet for an oversized head of a bearing bolt. The angle of incidence of the plates with respect to the bearing bush is in each case greater than 2°, preferably greater than 5°, and it can also be greater than 10°, wherein a full angle of > 4°, preferably >10° or > 20° results between plates lying opposite one another across the bush axis.The stiffening structure or the plates of the stiffening structure can be formed from a sufficiently elastically deformable metal or a plastic, which must likewise be elastically deformable and which can be, in particular, a fiber-reinforced plastic.Advantageous further developments of the invention are evident from the patent claims, the description and the drawings.The advantages of features and combinations of a plurality of features mentioned in the description are merely exemplary and can be applied alternatively or cumulatively without the advantages necessarily having to be achieved by embodiments according to the invention.With regard to the disclosure content-not the scope of protection-of the original application documents and of the patent the following applies: Further features can be taken from the drawings-in particular the geometries shown and the relative dimensions of a plurality of components with respect to one another and their relative arrangement and operative connection. The combination of features of different embodiments of the invention or of features of different patent claims is likewise possible deviating from the selected relations of the patent claims and is hereby excited. This also relates to features which are illustrated in separate drawings or are mentioned in the description thereof. These features can also be combined with features of different patent claims. Features listed in the patent claims can likewise be omitted for further embodiments of the invention, but this does not apply to the independent patent claims of the issued patent.The features mentioned in the patent claims and the description should be understood in terms of their number such that exactly this number or a greater number than the mentioned number is present, without the need for explicit use of the adverb "at least". Thus, if, for example, a bearing bush is mentioned, this is to be understood such that exactly one bearing bush, two bearing bushes or more bearing bushes are present. The features mentioned in the patent claims can be supplemented by further features or be the only features that the subject matter of the respective patent claim has.The reference numerals included in the claims do not represent a limitation on the scope of the subject matter protected by the claims. They are intended merely to make the claims more readily understood.BRIEF DESCRIPTION OF THE FIGURESThe invention is explained and described in more detail below with reference to preferred exemplary embodiments shown in the figures. FIG. 1 is a longitudinal section through a device according to the invention along a bushing axis. FIG. 2 shows an oval first end face, which is axially aligned with respect to the bushing axis, of a stiffening structure of the device according to FIG. 1 at its one axial end. FIG. 3 shows a circular second end face, which is aligned axially with respect to the bushing axis, of the stiffening structure according to FIG. 2 at its other axial end. FIG. 4 is a side view of the stiffening structure according to FIGS. 2 and 3. FIG. 5 shows the axially oriented first end face of a further stiffening structure, which is modified in relation to FIG. 2, at its one axial end. FIG. 6 shows the axially aligned rounded-off square first end face of a further stiffening structure at its one axial end. FIG. 7 shows the axially aligned triangular first end face of a further stiffening structure at its one axial end. FIG. 8 shows the axially aligned star-shaped first end face of a further stiffening structure at its one axial end. FIG. 9 is a longitudinal section through a further embodiment of the device according to the invention with a stiffening structure having flat plates, and FIG. 10 is an axial top view of the plates of the stiffening structure of the device according to FIG. 9 at one axial end thereof.DESCRIPTION OF THE FIGURESOf a device 1 according to the invention, the parts thereof essential for the present invention are shown in FIG. 1. The device 1 has a spring body 2 made of elastomer material 3. A bearing bush 4 for a bearing bolt 5 is formed in the spring body 2. The bearing bush 4 extends along a bush axis 6 through the spring body 2 and is open at its axial ends 7 and 8. A free passage cross section 9 of the bearing bush 4 which is circular here is bounded around the bush axis 6 by elastomer material 3. At the one axial end 7 of the bearing bush 4, a stiffening structure 10 is embedded in the elastomer material 3. The stiffening structure 10 extends here as far as the other axial end 8 of the bearing bush 4. the stiffening structure 10 is completely sheathed by the elastomer material 3, so that it ends practically shortly before the axial ends 7 and 8. With its inner periphery 12, the stiffening structure encloses virtual circles around the bushing axis 6. The virtual circle enclosed by the inner periphery 12 at the one axial end 7 has a smallest diameter 11 of all these circles. By elastic deformation of the stiffening structure 10, this diameter 11 of the virtual circle enclosed by the inner periphery 12 at the one axial end 7 can be elastically expanded in an insertion direction 13 when the bearing bolt 5 is inserted, in order to allow a radially oversized head 14 of the bearing bolt 5 to pass through the bearing bush 4. After the head 14 has passed through, the stiffening structure 10 returns to its initial shape and then secures the bearing bolt 5 against undesired extraction from the bearing bush 4. The present embodiment of the bearing bolt 5 abuts on the other axial end 8 of the bearing bush 4 via a radial collar 15. At the other axial end 8, too, the bearing bush 4 is reinforced by the reinforcing structure 10, even if the diameter of the circle enclosed by its inner periphery 12 is larger here. Specifically, the stiffening structure 10 according to FIG. 1 has an oval cross section in a region 16 at the one axial end 7, as shown in FIG. 2, and a circular cross section of its inner periphery 12 in a region 17 at the other axial end 8, as shown in FIG. 3.FIG. 2 is a view opposite to the insertion direction 13 onto an end face 18 of the stiffening structure 10 at the one axial end 7. the diameter 11 of the virtual circle 21 enclosed by the inner circumference 12 of the stiffening structure 10 at the one axial end 7 around the bushing axis 6 is here somewhat less than 1 / 6 of a circumferential length of the inner circumference 12 deformed oval transversely to the bushing axis 5.FIG. 3 shows the other end face 19 of the same stiffening structure 10. the inner periphery 12 is circular here and has the same peripheral length as in FIG. 2. the diameter 20 of the circular inner periphery 12 is twice as large as the virtual circle 21 enclosed by the oval inner periphery 12 of the stiffening structure 10 at the one axial end 7 about the bushing axis 6 according to FIG. 2.The side view of the stiffening structure 10 according to FIG. 4 illustrates that the stiffening structure 10 is drawn in from its circular shape according to FIG. 3 in its region 17 down to the oval shape at its end face 18 according to FIG. 2, wherein the diameter 20 of the virtual circle 21 enclosed by its inner periphery 12 is reduced down to the diameter 11. The stiffening structure 10 can be formed, for example, by simply compressing a tubular section in the form of a cylinder jacket section at the one axial end 7.FIG. 5 shows the end face 18 at the axial end 7 according to FIG. 1 of another embodiment of the stiffening structure 10. This realizes a modification of the oval end face 18 according to FIG. 2.FIG. 6 shows the end face 18 at the axial end 7 according to FIG. 1 of another embodiment of the stiffening structure 10, which is likewise closed around the bushing axis 6. The end face 18 is rounded square here, i.e. it has the shape of a regular square with rounded corners. The diameter 11 of the virtual circle 21 enclosed by its inner periphery 12 can be enlarged by elastically bending the sides of the square outwards. The end face 19 of the stiffening structure 10 according to FIG. 6 at the other axial end 8 according to FIG. 1 can be exactly circular, as is illustrated in FIG. 3.FIG. 7 shows the end face 18 at the axial end 7 according to FIG. 1 of a further embodiment of the stiffening structure 10 in the form of a triangle. Here, the diameter 11 of the virtual circle 21 enclosed by its inner periphery 12 is not a distance from portions of the inner periphery 12 opposite one another across the bush axis 6, but the diameter 11 of the largest circle 21 around the bush axis 6 within the triangle.FIG. 8 shows the end face 18 of an embodiment of the stiffening structure 10 with a star-shaped inner periphery 12 at the axial end 7 according to FIG. 1. Specifically, it is an eight-fold rotationally symmetrical eight-tooth star. In such a star shape, the circumferential length of the inner periphery 12 is particularly long about the bushing axis 6 compared to the diameter 11 of the circle 21 enclosed by the inner periphery 12 of the stiffening structure 10 at the axial end 7. In the embodiments of the stiffening structure 10 according to FIGS. 7 and 8, too, its end face 19 at the other axial end 8 can be circular, as is illustrated in FIG. 3.FIG. 9 shows an embodiment of the device 1 in a longitudinal section through the bearing bush 4 with inserted bearing bolt 5, in which the stiffening structure 10 is formed from individual planar platelets 22, which are set at flat angles of attack 23 to the bush axis 6, such that their distance in the insertion direction 13 decreases until it defines, at the axial end 7 of the bearing bush 4, the diameter 11 of the circle 21 enclosed by the inner circumference 12 of the stiffening structure 10 about the bush axis 6. The plates 22 are elastically connected to each other by the elastomeric material 3 and may also be elastically deformable.As viewed from the axial end 7 along the bushing axis 6, FIG. 10 shows end faces 24 of the plates 22 and in the process the arrangement of the plates 22 relative to the here circular free passage cross section 9 of the bearing bushing 4. It can have, for example, an oval or polygonal shape. In addition, both a circular and an oval or polygonal or otherwise shaped free passage cross section 9 can be provided with grooves, grooves or the like in the elastomer material 3 running along the bushing axis 6, as is fundamentally known from the prior art. This applies not only to the embodiment of the stiffening structure 10 according to FIGS. 9 and 10, but to all embodiments of the stiffening structure 10 disclosed here.LIST OF REFERENCE CHARACTERS1 Device 2 Spring body 3 Elastomer material 4 Bearing bush 5 Bearing bolt 6 Bush axis 7 Axial end 8 Axial end 9 Free passage cross section 10 Stiffening structure 11 Diameter 12 Inner periphery 13 Insertion direction 14 Head 15 Radial collar 16 Region 17 Region 18 End face 19 End face 20 Diameter 21 Virtual circle 22 Platelets 23 Angle of attack 24 End face

Claims

Device (1) having - a spring body (2) made of elastomer material (3) and - a bearing bush (4) which is formed in the spring body (2) and extends along a bush axis (6) and is open at its axial ends (7, 8), - a free passage cross section (9) of the bearing bush (4) around the bush axis (6) being bounded by elastomer material (3), - a stiffening structure (10) being arranged around the bush axis (6) and being embedded in the elastomer material (3) at one of the axial ends (7, 8) of the bearing bush (4), - the stiffening structure (10) including a virtual circle (21) around the bush axis (6) with its inner circumference (12) at the one axial end (7), and being elastically expandable away from the bush axis (6), A method for increasing a diameter (11) of the virtual circle (21) enclosed by its inner periphery (12), characterized - in that at the one axial end (7) of the bearing bush (4) a circumferential length of the inner periphery (12) of the non-widened stiffening structure (10) about the bush axis (6) is at least 3.5 times as long as the diameter (11) of the virtual circle (21) enclosed by the inner periphery (12) about the bush axis (6) and - in that the stiffening structure (10) extends towards the other axial end (8) of the bearing bush (4), wherein the diameter (11) of the virtual circle (20) enclosed by its inner periphery (12) increases towards the other axial end (8) of the bearing bush (4).Device (1) according to claim 1, characterised in that at the one axial end (7) of the bearing bush (4) the circumferential length of the inner periphery (12) of the non-widened stiffening structure (10) about the bush axis (6) is at least 4 times and preferably at least 5 times as long as the diameter (11) of the virtual circle (21) enclosed by the inner periphery (12) about the bush axis (6).Device (1) according to one of the preceding claims, characterized in that the inner periphery (12) of the non-widened stiffening structure (10) at the one axial end (7) of the bearing bush (4) is - oval or - three-, four-, five- or hexagonal or - rounded three-, four-, five- or hexagonal or - star-shaped or - rounded star-shaped.Device (1) according to one of the preceding claims, characterized in that the stiffening structure (10) runs around the bush axis (6) closed at the one axial end (7) of the bearing bush (4).Device (1) according to one of the preceding claims, characterized in that the stiffening structure (10) has apertures closed at the edges.Device (1) according to one of the preceding claims, characterized in that the inner periphery (12) of the stiffening structure (10) approaches a circular shape towards the other axial end (8) of the bearing bush (4).Device (1) according to one of the preceding claims, characterized in that the stiffening structure (10) has a plurality of planar plates (22) which follow one another along its inner periphery (12).Device (1) according to claim 7, characterised in that the plates are set at an angle of incidence (23) > 2°, preferably at an angle of incidence (23) > 5°, relative to the bushing axis (6).Device (1) according to one of the preceding claims, characterized in that the stiffening structure (10) is formed from metal or a plastic, in particular a fibre-reinforced plastic.

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