This application is a United States National Phase application of International Application PCT/DE2006/000935 and claims the benefit of priority under 35 U.S.C. §119 of German Patent Application DE 10 2005 025 551.5 filed Jun. 1, 2005, the entire contents of which are incorporated herein by reference.
The present invention pertains to a joint and/or bearing arrangement as well as to a motor vehicle with one or more such joint and/or bearing arrangement(s), especially in chassis and/or steering parts.
In joint arrangements that have a fixed pivot consisting of, for example, steel, which is to be held, for example, in wheel carriers, suspension arms or other similar carriers consisting of a softer material, for example, an iron or aluminum casting, which have a mounting opening, it is difficult to achieve a stable and low-tolerance connection of the pivot in the mounting opening without excessively stressing the softer material. It is known that a fixed sleeve can be pressed into the carrier for this purpose. However, this has the drawback that strong forces act on the material surrounding the mounting opening during this pressing in, and these forces may lead to a widening of the mounting opening and, since frequently only a few mm of material are available there, they may excessively weaken the carrier.
Furthermore, it is known that a conical disk can be pressed onto the pivot. The pivot has a parallel-walled section for this, onto which the conical disk is pressed such that a conical section of the pivot can be braced in relation to an oblique surface of the conical disk by an axial pull. The oblique contact surface of the pivot, which is effective for the force transmission to the conical disk, is very small, and, moreover, a weakening arises at the transition from the conical pivot section to the axial section, especially when bending stress develops.
The basic object of the present invention is to achieve an improvement of the holding of the pivot in the mounting opening.
According to the present invention the pivot pin remains free from a weak point in the area of the force transmission and it is also unnecessary to press a sleeve into the mounting opening. The carrier surrounding this opening is therefore stressed only minimally and may be very thin and formed from a relatively soft and lightweight material, for example, also from a light alloy casting. The ring body does not have to be pressed onto the pivot.
Nevertheless, the tapering area may have, at least in a part of its axial extension, a slope angle of 15° to 20° relative to the axis of the pivot and may also make possible a high axial prestress.
Nevertheless, pressing of the ring body onto the pivot or an intimate, self-locking connection is possible when the tapering area is stepped and an axially parallel, cylindrical section or a section of a smaller slope is formed in its direction facing away from the end of the pivot. As a result, the area of the pivot supported on the ring body, especially a conical disk, can nevertheless perform, unaffected, a maximum force transmission to the conical disk. A step on the side facing away from the end of the pivot is thus harmless.
When the tapering area has a variable slope decreasing towards the end of the pivot, especially good supporting can be ensured against bending stress while the axial prestress is high at the same time. The slope may pass over into a cylindrical area that adjoins the end of the pivot and has, for example, parallel walls, without a kink.
Only low requirements are to be imposed on the outer contour of the open or closed ring body. This ring body does not need to be pressed into the carrier of the mounting opening but it may also be held, for example, by bonding or other measures. As a result, different external shapes and outer contour of the ring body are possible as well. For example, this contour may also be parabolic, hyperbolic, conical or truncated cone-shaped.
If the ring body consists of a material that has, e.g., the same strength as the joint pivot, the risk of plastic deformation of one of the two parts is prevented. The acting forces and stresses can be distributed uniformly between these.
Such joint or bearing arrangements can be subjected with the axial prestress both axially and also intensely to bending because of the large two-dimensional support.
For axial prestressing, the pivot may have a thread at the pivot end and can be prestressed in a defined manner by means of a corresponding nut.
A joint arrangement according to the present invention can thus also be used on highly stressed and yet weight-optimized brackets of parts having a greater strength in mounting openings of softer parts, for example, within chassis and/or steering parts of motor vehicles, for example, in the support of parts of the wheel suspension.
Other advantages and features of the present invention appear from exemplary embodiments of the subject of the present invention, which are shown in the drawings and will be described below. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.
In the drawings:
Referring to the drawings in particular, the joint arrangement 1 shown in the first exemplary embodiment according to
Joint and/or bearing arrangements 1, 101, 201, 301, 401 according to the present invention may, however, have a great variety of designs. In any case, they comprise a design of the joint or bearing body 2, 102, 202, 302, 402, which is pivot-shaped at least in some areas and which can be held in a fixed manner in a mounting opening, here a press-in opening 6 of a suspension arm 7, for establishing a connection between an opening 6 in a relatively soft material and a body 2 having a greater strength. The suspension arm 7 consists, for example, of a relatively soft cast or forged aluminum, magnesium or iron material and may have only little material around the opening 6, for example, with a thickness of only 2 to 5 mm, in order to thus keep the dimension and the weight of the assembly unit as low as possible.
Such a joint arrangement 1, 101, 201, 301, 401 may be pressed in axially with a press fit. The joint may be manufactured with diameter tolerances in the range of a few hundredths of one mm, and so may the internal dimension of the opening 6 of the receiving body 7.
For being firmly supported in the opening 6 of the part, which is especially a chassis or steering part 7, the joint body 2 according to
As is apparent from
Towards the pivot end 9, the end 17 of the tapering section 8 may be joined by a narrower and at least partially parallel and hence cylindrical or slightly tapering area 11, which has a sufficiently small diameter to pass through the opening 6 even at its narrowest point and to open into a thread 12 for cooperating with a nut 13 or with another tightening element. The pivot 2 can be axially prestressed hereby. Such a joint and/or bearing arrangement 1 can counteract both radial loads, e.g., in guiding joints, and axial and radial loads, for example, in support joints.
The largest possible contact area is necessary between the tapering area 8 and the ring body 10 for high loads.
A transition 14 is located for this purpose according to the present invention between the tapering section 8 supported at the ring body and the thinner section 11 adjoining the pivot end 9 outside the axial extension of the ring body 10 in the direction of the pivot end 9. As a result, the ring body 10 can have full contact here (see
It becomes clear in the joint arrangement 401 according to
The tapering area 8 supported at the ring body 10 in the mounted position has a slope angle that is uniform here in relation to the axis 15 of the pivot 2, equaling 15° to 20°, in a part 8a, which assumes the entire axial extension of the area 8 in the first exemplary embodiment according to
The smaller the slope angle of area 8, the sooner is also the pressing on of the ring body 10, designed as a conical disk here, made possible, without this ring body 10 being able to slip off from the pivot 2.
Provisions are made herefor for the joint arrangement 101 according to the second exemplary embodiment according to
In addition or as an alternative to the step 16, the tapering area 8 may also have a variable slope decreasing towards the pivot end 9 according to
In the concave embodiment of the joint or bearing arrangement 202 according to
The conditions are exactly the opposite in the embodiment according to
In any case, there must be a sufficiently great slope at least in a partial area of section 8 in order to make it possible to achieve an axial prestressing via the tightening element 13.
The shape of section 8 may therefore be, on the whole, both hyperbolic and parabolic, with or without steps, or another shape is possible as well, but a pivot end-side transition 14 to the further, narrower section 11 is always located outside the supported area 8 at the ring body 10, 110, 210, 310.
The connection between the supported area 8 and the ring body 10, 110, 210, 310 may have various designs; besides pressing on, a bonding may, for example, be possible as well. The connection may also be brought about by sealing 5 alone in case of a mere contact.
The outer contour of the ring body 10, 10a, 110, 210, 310 facing the inner wall of the mounting opening 6 may also have a different shape and be, for example, parabolic, hyperbolic or conical.
The ring body 10, 10a, 110, 210, 310 does not always have to have a rotationally symmetrical design with the pivot axis, but it may also be elliptical or elongated in another manner in the opposite direction in case of a bending stress on the joint or bearing arrangement with a preferential direction of force, e.g., in only one plane in case of a steadily recurring bending, for example, against this stress. The pivot 2, 102, 202, 302, 402 itself may now also have an adapted, for example, elliptical cross section.
Various designs of the outer surfaces 18 of the conical disk 10, 10a, 110, 210, 310, which are directly in contact with the softer component 7, are conceivable as well, and there should be an axial and radial support depending on the requirements. Moreover, a large contact area is helpful here as well in order to avoid excessive punctiform loads on the relatively soft component 7 and to avoid the risk for plastic deformations.
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.
Number | Date | Country | Kind |
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10 2005 025 551.5 | Jun 2005 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/DE06/00935 | 5/31/2006 | WO | 00 | 11/30/2007 |