Bearing arrangement for an adjustment device in a motor vehicle

Abstract

Bearing arrangement for an adjustment device in a motor vehicle, with a base part which has at least one bearing recess, and with a bearing element located within the bearing recess, wherein the bearing recess and the bearing element have different cross-sectional shapes, and wherein the diameter of the bearing element has a section-wise oversize compared to the diameter of the bearing recess, characterized by that either the bearing recess (2a, 2b, 2c) in the base part (1) has a non-circular cross-section and the bearing element (4, 6) has a circular cross-section, or the bearing recess in the base part has a circular cross-section and the bearing element has a non-circular cross-section, and that of the components base part (1) and bearing element (4, 6), the component (1), which has the non-circular cross-section, is made of a softer material than the component (4, 6) with the circular cross-section.

Description

[0001] The invention relates to a bearing arrangement for an adjustment device in a motor vehicle, comprising a base part which has at least one bearing recess, and a bearing element mounted within the bearing recess, wherein the bearing recess and the bearing element have different cross-sectional shapes, and wherein the diameter of the bearing element has a section-wise excess compared to the diameter of the bearing recess.

[0002] Such a bearing arrangement is known from German patent application DE 103 29 237 A1. In the bearing arrangement described in this document, a bearing element extends through a bearing recess in the base part, wherein the cross-section of the bearing element is circular or disk-shaped and accordingly has a circular edge contour. The base part has a bearing recess, which is initially also circular and whose diameter is larger than the diameter of the bearing element. In order to hold the bearing element without play in the bearing recess, at least one deformation area is provided at the edge of the bearing recess, which, due to plastic deformation of the base part, projects radially inwards and acts as a radial support for the bearing element.

[0003] To create these deformation areas, each deformation area on the base part is assigned a weakening area, by means of which the deformation areas are formed, for example by material displacement.

[0004] The resulting deformation of the bearing recess compensates for the bearing play to such an extent that the bearing element is mounted in the recess without rattling. The deformation of the areas can be carried out either before or after the bearing element is inserted into the bearing recess.

[0005] If the bearing recess is formed before the axial insertion of the bearing element, the deformation areas are partially deformed radially outwards again when the bearing element is inserted into the recess, so that a backlash-free fit of the bearing element in the recess is automatically achieved, although a residual elastic preload remains. The bearing recess is thus formed in such a way that the diameter of the bearing element has an interference with the diameter of the bearing recess in the deformation areas.

[0006] A disadvantage of this method is that deforming the bearing recess requires at least one additional manufacturing step to create the deformation areas. Furthermore, a special tool suitable for this purpose is required. Both measures result in additional costs.

[0007] The task therefore arose to produce a storage arrangement in accordance with the general concept in a simpler and more cost-effective manner.

[0008] This problem is solved according to the invention by either having a non-circular cross-section in the base part and a circular cross-section in the bearing element, or having a circular cross-section in the base part and a non-circular cross-section in the bearing element, and by having the component with the non-circular cross-section made of a softer material than the component with the circular cross-section.

[0009] In this context, the term "soft material" means that the material is easily deformable and, according to its colloquial meaning, refers to both elastic and plastic deformability of the material.

[0010] As already explained, it is generally known to clamp a circular bearing element at a few points along its outer contour. However, this has previously involved, for example according to DE 103 29 237 A1, subsequent deformation of a bearing recess that was initially too large, or the insertion of additional bearing components into a circular bearing recess, as in German patent DE 28 38 768 C3 in the form of a floating bushing. Such solutions are complex to assemble and therefore also costly.

[0011] Instead of subsequently modifying an originally circular cross-sectional shape as before, the invention now provides for forming a corresponding cross-sectional shape directly during the manufacture of the base part or the bearing element. For this purpose, only the shape of the stamping or injection mold required for production needs to be designed accordingly.

[0012] This eliminates the manufacturing step for forming deformation areas, as well as the tooling required for this purpose and the production and assembly of additional bearing components.

[0013] In contrast to the designs known from DE 103 29 237 A1, it can also be provided that the bearing recess has a circular cross-section and the bearing element has a cross-sectional shape that deviates from the circular shape.

[0014] Here too, it is intended that the component with the non-circular cross-sectional shape is made of a softer material than the component with the circular cross-sectional shape.

[0015] Advantageous embodiments and further developments of the invention are shown in the exemplary embodiment described below with reference to the drawing. The drawing shows: Fig. 1 a bearing arrangement according to the invention, Fig. 2 a bearing cage as a separate part, Fig. 3 an adjustment device with a bearing arrangement designed according to the invention.

[0016] The Fig. Figure 3 shows a gearshift lever arrangement for a motor vehicle. A gearshift lever 11, which is suitable, for example, for actuating a flasher unit or windshield wiper switch, is gimbal-mounted on a housing 5.

[0017] To form a bearing arrangement for the shift lever 11, a bearing cage 1 is provided, which is pivotably mounted on the housing 5 about a vertical axis. The shift lever 11 itself is pivotable about a horizontal axis by means of bearing elements 4 that engage in bearing recesses (2a, 2b) of the bearing cage 1. Of the two bearing recesses (2a, 2b) that receive the bearing elements 4 of the shift lever 11, one is located in the Fig. 3 only a storage recess 2b is recognizable.

[0018] The bearing cage 1 as a separate part is in the Fig. Figure 2 shows the bearing cage 1 as a one-piece injection-molded part in the form of a substantially cuboid hollow body. The interior of the bearing cage 1 is freely accessible from at least one outer surface. Through this open outer surface, the horizontally arranged bearing elements 4 of the shift lever 11 can be inserted into the bearing cage 1. The bearing elements 4 can be slid along guide sections 3 to bearing recesses (2a, 2b), into which the bearing elements 4 then snap into place.

[0019] To securely hold the shift lever 11 in the bearing recesses (2a, 2b), the axial extension of the bearing elements 4 must be an interference with the distance between the inner surfaces of the walls of the bearing cage 1 in which the bearing recesses (2a, 2b) are located. This requires that the walls of the bearing cage 1 be able to deform flexibly when the bearing elements 4 are inserted until they snap into the bearing recesses (2a, 2b).

[0020] For this purpose, the bearing recesses (2a, 2b) are designed as rings 7, which are connected to the edges 8 of the bearing cage 1 by ribs 9. In particular, the ribs 9 provide sufficient deformability of the bearing cage 1 for the insertion of the bearing elements 4.

[0021] The bearing cage 1 also shows, according to the illustration in the Fig. The bearing cage 1 has two bearing bushings (10a, 10b) molded onto its upper and lower outer surfaces. Unlike the bearing recesses (2a, 2b), which are designed as through holes, the bearing recesses 2c of the bearing bushings (10a, 10b) are designed as blind holes, so that the bearing elements 6 of the housing 5 engage in the bearing bushings (10a, 10b) but do not extend through them. When the bearing cage 1 is mounted onto the bearing elements 6 of the housing 5, the bearing cage 1 is axially compressed in its vertical direction, so that the bearing elements 6 snap into the bearing bushings (10a, 10b). Several clearances 12 molded into the wall of the bearing cage 1 in the vicinity of the bearing bushings (10a, 10b) ensure axial elastic deformation of the bearing cage 1.

[0022] The bearing recesses (2a, 2b, 2c) each have a distinctly non-circular inner edge contour. The shape of such an edge contour is shown in the Fig. 1 particularly clearly recognizable. The Fig. Figure 1 shows a section through the bearing bushing 10a with an inserted bearing element 6, which is attached to the one in the Fig. The housing 5 shown in section 3 is integrally formed with the bearing element. The bearing element 6 has either a circular or, as shown here, a disk-shaped cross-section.

[0023] The inner edge contour of the bearing bushing 10a has three first concave regions a with a constant radius R. Between these first regions a, the inner edge contour of the bearing bushing 10a forms second regions b, which protrude convexly into the interior of the bearing recess 2c. The bearing bushing 10a and the bearing element 6 have a common bearing center P. Before the bearing element 6 is inserted into the bearing bushing 10a, the minimum bearing radius R10 of region b, measured from the bearing center P, is smaller than the radius R6 of the bearing element 6. Therefore, the inserted bearing element 6 has an interference fit (R10 < R6) with the most prominent sections of regions b, thus elastically deforming the contact points B in the radial direction. Furthermore, depending on the material of the bearing bushing 10a, permanent, i.e., plastic, deformation may also occur in the bearing bushing 10a.This results in a surface contact at three contact points B, by which the bearing element 6 is held without play within the bearing recess 2c of the bearing bushing 10a.

[0024] Advantageously, the interference of the bearing element 6 is kept as small as possible, so that unnecessarily high frictional forces of the bearing element 6 in the bearing recess 2c are avoided. However, the interference is at least large enough that, even when taking into account the maximum expected component tolerances of the bearing bushing 10a and the bearing element 6, it does not fall below a specified minimum value.

[0025] The bearing recess 2c and the bearing element 6 can of course also have differently shaped edge contours, which in particular also have more than three points of contact with each other, but three points of contact B appear optimal with regard to a bearing element 6 that is on the one hand precise and on the other hand as frictionless as possible.

[0026] As the Fig. Figure 3 shows that the bearing element 4 of the shift lever 11, visible there, is mounted within the bearing recess 2b in the same way as the bearing element 6 in the bearing bushing 2c, according to the Fig. 1.

[0027] The kinematic reversal of this embodiment, in which a bearing element with a non-circular outer contour rests against the circular edge contour of a bearing recess, is also considered to belong to the scope of the invention.

[0028] As the Fig. As shown in Figure 1, the circumference of the bearing element 6 is held at three contact points B. At these three contact points B, the circular circumference of the bearing element is clamped to the bearing bushing 10a. Since the areas b of the bearing bushing 10a are deformed by the inserted bearing element 6, the contact points B are not point-like or linear in the direction of their axial extent, but each form a contact surface A, albeit a small one. Therefore, when the bearing element 6 is rotated, frictional forces must be applied between these contact surfaces A and the bearing element 6, but these forces are relatively small due to the relatively small contact areas.

[0029] It would be problematic, however, if the protruding second areas b were to press into the material of the bearing element 6. This would create an indentation at each of the three contact points B, which, since they always form at the contact points, would move along the circumference of the bearing element 6 when it rotates. The forces required to move several deformations around the circumference of the bearing element 6 are comparatively high, so that this would effectively lead to the bearing element 6 becoming jammed.

[0030] To achieve backlash-free yet smooth operation of the bearing element, it is essential that the radius of the non-circular component matches the radius of the circular component. This also applies to the previously mentioned kinematic reversal regarding the shapes of the bearing element and bearing bushing. To achieve this, the component with the non-circular contour must be manufactured from a softer material than the component with the circular inner or outer contour.

[0031] It is particularly advantageous to use the bearing arrangement according to the invention in conjunction with a lever mounted thereon, such as the one described in the Fig.3 gearshift lever 11 shown, since the frictional forces caused by the interference fit of the bearing element 4 require only a relatively small additional actuating force due to the leverage effect, which is mostly barely perceptible, and therefore has a less disturbing effect than a gearshift lever 11 bearing with play that is perceived as inaccurate. Reference sign 1 Base part (bearing cage) 2a, 2b, 2c Storage recess 3 guided sections 4 bearing elements (on the gearshift lever) 5 cases 6 bearing elements (on the housing) 7 rings 8 edges 9 ribs 10a, 10b Bearing bushings 11 Gearshift lever 12 releases a first areas b second areas A facility area B Point(s) of contact R radius (of the area a of the bearing bushing) R6 radius (of the bearing element) R10 bearing radius (of the base part) P bearing center

Claims

Bearing arrangement for an adjustment device in a motor vehicle, comprising a base part having at least one bearing recess, and a bearing element mounted within the bearing recess, wherein the bearing recess and the bearing element have different cross-sectional shapes, and wherein the diameter of the bearing element has a section-wise excess compared to the diameter of the bearing recess, characterized in that either the bearing recess (2a, 2b, 2c) in the base part (1) has a non-circular cross-section and the bearing element (4, 6) has a circular cross-section, or the bearing recess in the base part has a circular cross-section and the bearing element has a non-circular cross-section, and that of the components base part (1) and bearing element (4, 6), the component (1) having the non-circular cross-section is made of a softer material than the component (4, 6) with the circular cross-section. Bearing arrangement according to claim 1, characterized in that the base part (1) and the bearing element (4, 6) are produced by an injection molding or stamping process and that the final cross-sectional shapes of the bearing recess (2a, 2b, 2c) of the base part (1) and the bearing element (4, 6) are determined by the injection molding or stamping process. Bearing arrangement according to claim 1, characterized in that the bearing element (6) engages in the bearing recess (2c) or the bearing element (4) extends through the bearing recess (2a, 2b). Bearing arrangement according to claim 3, characterized in that the bearing recess (2a, 2b) is designed as a breakthrough in the base part (1). Bearing arrangement according to claim 3, characterized in that the base part (1) has at least one bearing bushing (10a, 10b) in which the bearing recess (2c) is designed as a blind bore. Bearing arrangement according to claim 1, characterized in that the base part (1) forms a bearing cage. Bearing arrangement according to claim 1, characterized in that the bearing arrangement supports a switching lever (11) for an electrical switch.

Images