Wheel rim and motor vehicle

Abstract

The present invention relates to a wheel rim (1) for a motor vehicle (2) for receiving a tire with through openings (4) arranged on a bolt circle (3) for passing wheel bolts and with a hub opening (5) for receiving a wheel hub. The essential aspect of the invention is that the wheel rim (1) has the following recesses (6, 7, 8), - a first recess (6) seen from the rear of a wheel rim, which extends from the hub opening (5) in a radial direction (10) outwards to near a through opening (4), - a second recess (7) seen from the rear of a wheel rim, which extends conically outwards from a through opening (4) in the radial direction (10), - a third recess (8) seen from the rear of a wheel rim, which extends in the circumferential direction (9) between two adjacent through-holes (4) in the radial direction (10). This significantly reduces the amplitude of an additional axial load acting on the wheel bolts.

Description

[0001] The present invention relates to a wheel rim for a motor vehicle for receiving a tire, according to the preamble of claim 1. The invention also relates to a motor vehicle with at least one such wheel rim.

[0002] DE 100 17 028 A1 discloses a wheel rim for a motor vehicle for accommodating a tire, with through holes arranged on a bolt circle for the passage of wheel bolts and with a hub opening for accommodating a wheel hub. The wheel rim has a recess, viewed from the rear of the wheel rim, which extends circumferentially between two adjacent through holes in the radial direction.

[0003] US Pat. No. 6,517,165 B1 discloses a generic wheel rim comprising a rim base for accommodating a tire and a disk welded to it, in which through-holes for wheel bolts are arranged. To achieve a weight reduction of the wheel rim, continuous recesses are provided in the circumferential direction between the individual through-holes.

[0004] Another wheel rim for a motor vehicle is known from CN 206520417 U, with through holes arranged on a bolt circle for accommodating wheel bolts. Outside the bolt circle, the wheel rim has continuous spokes extending to the rim base.

[0005] From DE 10 2020 205 204 A1, a wheel rim for receiving a tire is known, comprising a wheel disc permanently attached to the wheel rim, and at least one design element attached to the wheel rim and / or the wheel disc, wherein the wheel disc and the design element have common openings for receiving and / or passing through wheel bolts.

[0006] In general, the design characteristics of a wheel rim significantly determine the loads acting on wheel bolts during operation. The wheel bolts are typically subjected to oscillating loads during driving, with the amplitude of an additional axial bolt force acting on the wheel bolts during driving being a particularly important parameter when evaluating wheel rim variants during the development process.

[0007] A disadvantage of wheel rims known from the prior art, for example with cloverleaf-shaped depressions and / or recesses arranged in the circumferential direction between adjacent through openings for receiving wheel bolts, is that these have an unsatisfactory wheel bolt load during driving operation.

[0008] The present invention therefore addresses the problem of providing an improved or at least an alternative embodiment for a wheel rim of the generic type, by means of which, in particular, a wheel bolt load during driving can be reduced.

[0009] This problem is solved according to the invention by the subject matter of independent claim 1. Advantageous embodiments are the subject matter of the dependent claims.

[0010] The present invention is based on the general idea of ​​providing, in a wheel rim for a motor vehicle for accommodating a tire, a wheel rim with through-holes arranged on a bolt circle for the passage of wheel bolts and a central hub opening for accommodating a wheel hub, pocket-like recesses, as viewed from the rear side, which are designed and arranged in such a way that they significantly reduce the wheel bolt loads occurring during driving, in particular the amplitude of an additional axial bolt force. The pocket-like recesses, as viewed from the rear side of the wheel rim, do not represent openings, but merely depressions.According to the invention, the wheel rim has the following recesses: a first recess, viewed from the rear of the wheel rim, which extends radially outwards from the hub opening to close to a through-opening in which the wheel bolt is mounted when mounted on the motor vehicle; a second recess, viewed from the rear of the wheel rim, which extends conically widening radially outwards from a through-opening; and a third recess, viewed from the rear of the wheel rim, which extends circumferentially between two adjacent through-openings in the radial direction, in particular in a slot-like manner. The provision of these three recesses has led to a considerable reduction in the wheel bolt load occurring during driving operation and, in particular, to a considerable reduction in the amplitude of an additional axial bolt force occurring during driving operation.The depth of the individual recesses depends on the geometry of the wheel rim, whereby the aim is to achieve a maximum possible depth at which the operational strength of the wheel rim can still be reliably guaranteed.

[0011] In an advantageous development of the wheel rim according to the invention, an inner contour of at least one first recess is oriented towards an inner contour of an associated through-opening. The inner contour of the associated through-opening is decisively determined by a diameter of the wheel bolts and by an outer contour of a head of the wheel bolts. By orienting the inner contour of the at least one first recess towards the inner contour of the associated through-opening, a comparatively small wall thickness can be achieved between the first recess and the through-opening, which can lead, on the one hand, to a considerable reduction in the additional axial screw force, in particular by 10 to 40%, and, on the other hand, also to a reduction in the weight of the wheel rim, which is of great advantage, particularly in motor vehicles designed as sports cars.A depth of at least one first recess in the axial direction extends almost to the receptacle for a hub cover, whereby a wall thickness can also be significantly reduced here.

[0012] In a particularly preferred embodiment of the wheel rim according to the invention, at least one first recess tapers outwards in the radial direction, in particular at least one first recess tapers conically outwards in the radial direction. The taper can be observed when viewed in the axial direction. Alternatively, it is also conceivable for at least one first recess to have a constant width in the radial direction, which in particular corresponds to a width of the associated through opening in the circumferential direction. What both embodiments of the first recess have in common is that they lead to a significant reduction in the amplitude of an additional axial screw force, whereby the (vibration) load on the wheel bolts during driving can be significantly reduced.

[0013] In a further advantageous embodiment of the wheel rim according to the invention, an outer side of at least one first recess facing the associated through-opening is concavely curved. The concave curvature of at least one outer side of at least one first recess facing the associated through-opening allows a wall thickness between the first recess and the associated through-opening to be reduced, which contributes to a weight reduction of the wheel rim. Furthermore, this allows for a visually extremely appealing design.

[0014] In a further advantageous embodiment, the outer side of at least one first recess facing the associated through-opening is curved with the same radius as the associated through-opening. This allows for a particularly precise and consistently thin wall thickness to be created between the first recess and the through-opening.

[0015] Advantageously, an inner side of at least one second recess facing the associated through-opening is concavely curved, in particular curved with the same radius as the associated through-opening. This also allows a minimal and, in particular, consistent wall thickness to be achieved between the second recess and the associated through-opening, which is sufficient to absorb the loads acting on the wheel rim during driving, but at the same time is reduced to such an extent that both the amplitude of the additional axial bolt force acting on the wheel bolts and the weight are reduced as much as possible.

[0016] In a particularly preferred embodiment of the solution according to the invention, at least one third recess is designed as a slot. Such a slot-like third recess can significantly reduce the amplitude of the additional axial bolt forces acting on the wheel bolts during driving.

[0017] A depth of the third recess is preferably designed to be maximum, i.e. a wall thickness surrounding the slot-like third recess is limited only by conditions of economical production and reliable absorption of loads occurring during driving operation.

[0018] Additionally or alternatively, it can also be provided that at least one third recess tapers outward in the radial direction, in particular conically, when viewed in the axial direction. The taper can be seen in the axial direction when viewed from the rear of the wheel rim. Such a conical taper also enables the reduction in the amplitude of the additional axial loads on the wheel bolts, which is associated with the pocket-like recesses, and can also simplify manufacturing.

[0019] It is advisable for at least one second recess to be as wide in the circumferential direction on its inner side facing the associated through-opening as the through-opening and to widen radially conically outwards at an angle α between 50° and 80°. The width of the inner side of the second recess facing the associated through-opening is particularly design-dependent. This second recess is placed as close as possible to the associated through-opening for manufacturing purposes and with regard to the desired reduction in the amplitude of the additional axial loads acting on the wheel bolts. The only requirement is to ensure a minimum wall thickness between the second recess and the associated through-opening in order to reliably absorb the loads occurring during driving.

[0020] The present invention is further based on the general idea of ​​equipping a motor vehicle with at least one wheel rim described in the previous paragraphs, thereby transferring the advantages described with regard to the wheel rim to the motor vehicle. Specifically, these advantages lie in particular in a significant reduction in the additional axial loads acting on the wheel bolts during driving, compared, for example, to cloverleaf-shaped recesses located circumferentially between two adjacent through-holes. This also allows, for example, the wheel bolts themselves to be thinner and thus lighter and more cost-effective, without this resulting in a reduction in the loads they can absorb.

[0021] Further important features and advantages of the invention emerge from the subclaims, from the drawings and from the associated description of the figures based on the drawings.

[0022] It is understood that the features mentioned above and those to be explained below can be used not only in the respective combination specified, but also in other combinations or on their own, without departing from the scope of the invention defined by the claims. Components mentioned above and to be mentioned below of a higher-level unit, such as a device, apparatus, or arrangement, which are designated separately, may form separate parts or components of this unit or be integral areas or sections of this unit, even if this is shown differently in the drawings.

[0023] Preferred embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description, wherein the same reference numerals refer to the same or similar or functionally identical components.

[0024] They show, schematically, Fig. 1 a view from the rear of a wheel rim of a wheel rim according to the invention with first, second and third recesses according to the invention, Fig. 2 a view from the rear of a wheel rim of a possible embodiment of a first recess according to the invention, Fig. 3 a sectional view along the section plane AA through the corresponding Fig. 2 first depression shown, Fig. 4 a detailed view from the rear of a wheel rim of a second recess according to the invention, Fig. 5 a sectional view along the section plane BB through the second recess corresponding to the Fig. 4, Fig. 6 a sectional view through a third recess according to the invention.

[0025] According to the Fig. 1, a wheel rim 1 according to the invention for a motor vehicle 2 according to the invention for receiving a tire (not shown) has a plurality of through-holes 4 arranged on a bolt circle 3 for passing through wheel bolts (also not shown). Also arranged centrally is a hub opening 5 for receiving a wheel hub (also not shown) of the motor vehicle 2.

[0026] The wheel rim 1 can in particular be made of a light metal alloy, for example of aluminum, or of steel.

[0027] In order to reduce the axial additional loads / forces on the wheel bolts fixing the wheel rim 1 to the motor vehicle 2 during driving, the wheel rim 1 according to the invention has the following recesses 6, 7, 8 (see also the Fig. 2 - 6).

[0028] A first recess 6, seen from the rear side of the wheel rim, which extends radially outwards from the hub opening 5 to close to a through opening 4 (compare in particular also the Fig. 2 and Fig. 3), have a second recess 7, seen from the rear side of the wheel rim, which extends from a through-opening 4 radially outwards (in the radial direction 10 outwards) in a conical manner, as shown in the Fig. 1 and 4 and 5, and a third recess 8, seen from the rear side of the wheel rim, is provided, which extends in the circumferential direction 9 between two adjacent through openings 4, in particular centrally between two adjacent through openings 4, at least approximately in the radial direction 10.

[0029] The recesses 6, 7, 8 are merely blind hole-like or pocket-like recesses and not recesses that completely break through the wheel rim 1.

[0030] In general, in connection with the described first, second or third recesses 6, 7, 8, these are arranged on the wheel rim 1 according to the invention and thus lead to a reduction of an additional axial load occurring during driving and acting on the wheel bolts.

[0031] If you now look at the first depression 6, you can see that this corresponds to the Fig. 1 has a width which is constant in the radial direction 10 and which is at least substantially oriented towards or corresponds to a width of the associated through-opening 4, ie an inner diameter of the associated through-opening 4. Alternatively, it is of course also conceivable that the at least one first recess 6 tapers outwards in the radial direction 10, in particular conically, as is the case according to the Fig. 2. The tapering can be seen when viewed from the rear of the wheel rim in the axial direction. Both designs have in common that they significantly reduce the amplitude of the additional axial force acting on the wheel bolts during driving.

[0032] An outer side 11 of at least one first recess 6 facing the associated through-opening 4 can be concavely curved (compare the Fig. 1 and Fig. 2). The outer side 11 of at least one first recess 6 facing the associated through-opening 4 can in particular be curved with the same radius as an inner contour of the associated through-opening 4. This makes it possible to achieve a particularly thin and at the same time consistent wall thickness between the first recess 6 and the associated through-opening 4. The wall thickness is designed such that it easily withstands the loads occurring during driving, but is also reduced to such an extent that, on the one hand, the weight and, on the other hand, the amplitude of the additional axial loads on the wheel bolts occurring during driving can be reduced.

[0033] Looking at the Fig. 3, it can be seen that an inner contour 12 of at least a first recess 6 is oriented towards an inner contour 13 of the through-opening 4 or runs along this, in particular runs parallel to it, whereby a wall thickness between the first recess 6 and the through-opening 4 can likewise be reduced. The first recess 6 is preferably brought as close as possible to the associated through-opening 4 and is open towards the hub opening 5. A depth T6 of the first recess 6 preferably extends as far as a receptacle 14 for a hub cover (not shown), which covers the wheel hub when the wheel rim 1 is mounted on the motor vehicle 2. As a result, the wall thickness between the first recess 6 and the receptacle 14 can be reduced as much as possible, which contributes to reducing both the weight and the additional axial loads acting on the wheel bolts during driving.

[0034] If one considers the second recesses 7 according to the invention, one can Fig. 1 and Fig. 4 that they have an inner side 15 facing an associated through-opening 4, which is also concavely curved. A curvature of the inner side 15 of at least one second recess 7 facing the associated through-opening 4 can be designed with the same radius as the associated through-opening 4, whereby a minimal and nevertheless constant wall thickness can be achieved between the inner side 15 of the second recess 7 and the associated through-opening 4. In the circumferential direction, a width of the second recess 7 on the inner side 15 can correspond approximately to the width, ie the diameter, of the through-opening 4. A depth T7 of the second recess 7 in the axial direction relative to an axis 16, which according to the Fig. 1, Fig. 2 and Fig. 4 perpendicular to the sheet plane and according to the Fig. 3 and 5 and 6 runs parallel to the plane of the sheet, can be made as deep as possible in order, on the one hand, to reduce the weight of the wheel rim 1 and, on the other hand, to still realize the effects achievable by the invention with regard to reducing the amplitude of the additional axial force acting on the wheel bolts during driving.

[0035] At least one second recess 7 can widen radially conically outwards with an angle α between 50° and 80°, as is the case, for example, according to the Fig. 1 and Fig. 4 is shown.

[0036] Looking at the Fig. 1 and 6, it can be seen that the third depressions 8 shown there are slit-like, in particular slit-like extending in the radial direction 10, wherein additionally or alternatively it can also be provided that at least one third depression 8 tapers outwards in the radial direction 10, in particular conically, as is shown in the Fig. 1. The taper can be seen when viewed from the rear of the wheel rim in the axial direction. A depth T8 is also designed as deep as possible, with limitations imposed only by manufacturing constraints or the loads to be absorbed.

[0037] In general, the recesses 6, 7, 8 provided according to the invention are used on the wheel rim 1 according to the invention and contribute to reducing the additional axial loads acting on the wheel bolts during driving considerably, in particular by 20 - 30%, whereby the wheel rim 1 and / or the wheel bolts can be made thinner, for example, and thus not only in a resource-saving manner, but also more cost-effectively and weight-optimized.

Claims

[1] Wheel rim (1) for a motor vehicle (2) for receiving a tire, - with through holes (4) arranged on a bolt circle (3) for the passage of wheel bolts, - with a hub opening (5) for receiving a wheel hub, characterized by that the wheel rim (1) has subsequent recesses (6, 7, 8), - a first recess (6) seen from the rear of the wheel rim, which extends from the hub opening (5) in the radial direction (10) outwards to close to a through opening (4), - a second recess (7) seen from the rear of the wheel rim, which extends conically outwards from a through opening (4) in the radial direction (10), - a third recess (8) seen from a wheel rim rear side, which extends in the circumferential direction (9) between two adjacent through openings (4) in the radial direction (10). [2] Wheel rim (1) according to claim 1, characterized bythat a depth (T6) of at least one first recess (6) is oriented towards an inner contour (12) of an associated through-opening (4). [3] Wheel rim (1) according to claim 1 or 2, characterized by , - that at least one first recess (6) tapers outwards in the radial direction (10), in particular conically, or - that at least one first recess (6) has a constant width in the radial direction (10) which corresponds at least substantially to a width of the associated through opening (4). [4] Wheel rim (1) according to one of the preceding claims, characterized by that an outer side (11) of at least one first recess (6) facing the associated through opening (4) is concavely curved. [5] Wheel rim (1) according to claim 4, characterized bythat the outer side (11) of at least one first recess (6) facing the associated through-opening (4) is curved with the same radius as the associated through-opening (4). [6] Wheel rim (1) according to one of the preceding claims, characterized by that an inner side (12) of at least one second recess (7) facing the associated through opening (4) is concavely curved. [7] Wheel rim (1) according to claim 6, characterized by that the inner side (12) of at least one second recess (7) facing the associated through-opening (4) is curved with the same radius as the associated through-opening (4). [8] Wheel rim (1) according to one of the preceding claims, characterized by , - that at least one third recess (8) is slot-shaped, and / or - that at least one third recess (8) tapers outwards in the radial direction (10), in particular tapers conically. [9] Wheel rim (1) according to one of the preceding claims, characterized by that at least one second recess (7) on its inner side (15) facing the associated through-opening (4) is as wide in the circumferential direction as the associated through-opening (4) and widens conically outwards at an angle α of 50° ≤ α ≤ 80° in the radial direction (10). [10] Motor vehicle (2) with at least one wheel rim (1) according to one of the preceding claims.

Images