EP2760681A1

EP2760681A1 - Wheel

Info

Publication number: EP2760681A1
Application number: EP12772096.9A
Authority: EP
Inventors: Roman Müller; Thorsten WELTE
Original assignee: BBS Japan Co Ltd
Current assignee: BBS Japan Co Ltd
Priority date: 2011-09-30
Filing date: 2012-09-28
Publication date: 2014-08-06
Also published as: US9340066B2; JP6026543B2; JP2014528375A; DE102011083834A1; US20140246895A1; DE102011083834A9; WO2013045618A1

Abstract

The invention relates to a wheel (1), in particular a partially light-metal wheel and/or a light-metal wheel for motor vehicles, substantially comprising a rim (2) and a wheel spider (3), wherein the wheel spider (3) is made of a carbon-fiber-reinforced plastic. According to the invention, the wheel (1) has a clamping ring (4). The wheel spider (3) can be fastened to the rim (2) by means of the clamping ring (4).

Description

wheel

The invention relates to a wheel, in particular a light metal wheel for motor vehicles. The wheel basically consists of a rim and a wheel star. For the purposes of the invention, light-alloy wheels are understood to mean wheels which at least partially comprise a light metal, but may also comprise other materials, including non-metallic materials, including partial-light metal wheels.

Such wheels are known in the art as multi-piece wheels. Differences in the properties of the materials used pose challenges to the professional world and continue to provide room for improvement. In particular, the connection of the multiple parts of different material is always to improve.

These problems are achieved by a wheel with the characterizing features of claim 1 in combination with the above-mentioned features.

According to the invention, the wheel center consists of a metal or of a metal alloy, in particular of a light metal such as magnesium or aluminum. The rim consists of a carbon fiber reinforced plastic, in particular with a thermoplastic or duromer matrix. The Radstern is fastened by means of a clamping ring on the rim.

By means of such a clamping ring can achieve a defined to receive an operating load sufficient bias between the components to be connected. This proves to be advantageous in compensating for different coefficients of expansion of the carbon fiber reinforced plastic and the metal of the different components. The use of the clamping ring according to the invention leads to high strength of the connection of rim and wheel center. According to an advantageous embodiment, the rim has an inner rim of the rim and an outer rim of a rim, which each transition into a rim inner horn or a rim outer horn. The wheel center is supported axially inwards in a first circumferential contour, wherein the first circumferential contour is formed in the rim outer bed or in an area of the rim which is axially adjacent to the rim outer bed.

The clamping ring can slide on the contact surfaces in the radial direction. The contours of advantageous embodiments are matched in their inclinations and clamping lengths such that no significant change in the preload force occurs during cooling or when heated, and that centering can take place via the bevels.

According to a further advantageous embodiment, the clamping ring has a V-shaped or a U-shaped cross-section. Particularly advantageously, the clamping ring axially in nen a radially outwardly formed collar. The collar is supported axially outwardly in a second circumferential contour of the rim.

According to a further advantageous embodiment, the rim has a radially inward bulging, circumferential belly. The flanks of the abdomen are contours of the rim, in particular the first circumferential contour and the second circumferential contour.

When the vertical orientation of the wheel relative to the vertical, the flanks close particularly advantageously a connection angle, wherein the flanks are formed in particular in a connection area with a corresponding circumferential surface.

Under load - especially when cornering and thus by a side force - a bias of the clamping ring must be so large that the clamping ring remains securely connected to the rim and the wheel center. The inventively designed rim takes on the clamping ring with the proposed belly and its flanks such that in all driving situations of the vehicle, a lifting of the clamping ring of the wheel hub or the rim is avoided. According to a further advantageous embodiment of the clamping ring is connected by means of fastening elements with the rim or the wheel hub, in particular by means of screws screwed into the wheel center. The function of the clamping ring would not be used if the clamping ring were bolted to both the rim and with the wheel center. However, a screwing of the clamping ring for aesthetic reasons, regardless of the function can be quite attractive.

In an untensioned state of the clamping ring, when the not yet screwed clamping ring is in contact with the rim, in a ring region in which the Befestigungselemen- te are arranged, a first gap between the clamping ring and the rim or the wheel center is formed. The first gap is - reaching a tensioned state of the clamping ring - closable by tightening the fasteners.

The clamping ring is therefore biased when it comes to loads from driving situations of the vehicle. The bias results in a compression of a rim base and an expansion of the clamping ring. A deformation of the wheel can be neglected because of its design, cf. Embodiment.

According to a further advantageous embodiment, the wheel center has a plurality of spokes which extend from a hub area in a substantially radial direction. At the end, the spokes open into an outer ring corresponding approximately to an inner diameter of the rim.

According to a further advantageous embodiment, the screws are screwed into radially outer regions of the spokes, in particular in the outer ring facing, reinforced

Mouth areas of the spokes.

According to a further advantageous embodiment, the wheel center radially outward and the rim facing elevations and / or depressions and the rim corresponding to many corresponding to the wheel wells and / or corresponding elevations. According to a further advantageous embodiment, the clamping ring is formed curved radially inward. The clamping ring touches the rim in a row only axially inside with a collar, wherein preferably the clamping ring, the rim axially outside, if any, contacted by a circumferential sealing ring.

It is further particularly preferred that the clamping ring, in particular the collar outside the flank, of the connection region and / or outside the second circumferential contour, in particular in the radial direction, is spaced from the rim by a second gap, preferably in the axially outer region, and / or the wheel center, in particular the outer ring, outside the flank, the connection region and / or outside the first circumferential contour, preferably in the radial direction, from the rim by a third gap, in particular in the axially inner region, spaced.

It is in particular proposed that the second gap and / or the third gap is dimensioned or are such that in an expansion of the clamping ring, in particular of the collar, and / or the wheel, in particular of the outer ring, in the radial direction, in particular one Expansion due to thermal expansion at a predetermined first temperature, direct contact of the clamping ring, in particular of the collar, and / or the hub, in particular the outer ring, with the rim in the area outside the flank, the connection area, the first circumferential contour and / or the second circumferential contour is omitted.

Also, a wheel according to the invention may be characterized in that the connection angle is chosen such that in a thermal compression of the clamping ring, in particular of the collar, and / or the wheel, in particular the outer ring, in the radial direction and / or the axial direction , in particular due to thermal compression at a predetermined second temperature, the clamping ring, in particular the collar, and / or the wheel center, in particular the outer ring, on the flank, the first circumferential contour, the second circumferential contour, in particular in the connection area, under a Vorspan - Lung rests, wherein the bias voltage is preferably below a predetermined maximum voltage and / or above a predetermined minimum voltage, in particular over an entire temperature range between the second temperature and the first temperature.

Finally, it is proposed with the invention that the first temperature is about 120 ° C and / or the second temperature is about -40 ° C.

The invention will be explained in more detail below with reference to the exemplary embodiment illustrated in the figures. It is a classic spoke design with Y-shaped extending spoke webs chosen to illustrate the invention. Alternatively, all types of wheel stars or equivalent wheel elements can be used according to the invention.

The invention will be explained in more detail with reference to figures. Show it:

1 is a perspective view of a wheel that has been cut axially,

2 shows another axial section through an exploded view of the wheel,

Fig. 3 shows the axial section of Fig. 2 by the assembled wheel

Fig. 4 is a perspective view as an exploded view of the wheel and

5 is an enlarged view of an axial section, wherein a region around a clamping ring according to the invention has broken in an untensioned state,

6 is an auxiliary drawing for calculating a connection angle and

Fig. 7 is the enlarged view of Fig. 5, wherein the clamping ring is shown in a tensioned state.

FIGS. 1 to 5 and 7 show an exemplary embodiment of a wheel 1 according to the invention, in the present case a light metal wheel for motor vehicles with a wheel star 3 made of metal. tall and a rim 2 made of carbon fiber reinforced plastic. The Radstern 3 is fixed by means of a clamping ring 4 on the rim 2. In this case, the rim 2 is not injured, since the clamping ring 4 is seated only on the rim 2 and pulls the wheel 3 against the rim 2. By means of the clamping ring 4, a biasing force is applied to the components to be connected. Also, the Radstern 3 sits therefore only on the rim 2. It is advantageously no screwing into the rim 2 instead.

Identical parts are provided with the same reference numerals. For the sake of clarity, not all reference numbers are entered in all figures.

The rim 2 has a rim inner bed 21 and a rim outer bed 22. The area designated as rim interior bed is often also referred to as inner rim shoulder, and the area designated as outer rim bed 22 is often referred to as outer rim shoulder. These can be joined to the rim center safety elements to prevent slippage of the tire in the middle region of the rim. Both the rim inner bed 21 and the rim outer bed 22 merge into a rim inner horn 23 and a rim outer horn 24, respectively. Under axial inside in the sense of the present invention, therefore, the vehicle center longitudinal axis facing direction is to be understood, while under axially outside so the vehicle center longitudinal axis opposite side is to be understood. Thus, at least one first circumferential contour 25 is formed in the rim 2, in which the wheel center 3 can be used with a radially outer and axially inner contact contour. The Radstern 3 is thus added in the rim 2 supported axially inwardly.

The spider 3 has a plurality of spokes 31, which extend from a hub region 32 in a substantially radial direction r. The spokes 31 open radially outward in an approximately an inner diameter of the rim 2 corresponding outer ring 33. The contact contour of the Radsterns 3 to the rim 2 is formed in the present embodiment by means of the outer ring 33. The outer ring 33 has, in addition to the peripheral contact contour circumferentially elevations 28. The elevations 28 are facing the rim 2 and the rim 2 is formed accordingly. The elevations 28 are arranged distributed over the circumference on the outer ring 33. In addition, the outer ring 33 has a recess 29 which is intended to receive a corresponding elevation of the rim 2. The elevations 28 and the recess 29 serve as anti-rotation to accommodate braking and drive torque. The elevations 28 engage in recesses 38, which are formed in accordance with FIG. 2 in the rim 2, a.

The rim 2 has a second circumferential contour 26 radially inward and axially inward. In order to be able to bear against the second circumferential contour 26 axially outward, the clamping ring 4 has a radially outwardly formed collar 41.

The first circumferential contour 25 and the second circumferential contour 26 are flanks 51 of a circumferential bulge 27 bulging radially inward from the rim 2. This area 27 is often also referred to generally as the low-level bed of the rim 2.

The clamping ring 4 is screwed by means of screws 5 in the wheel hub 3 (Fig. 1, Fig. 3) or screwed (Fig. 2, Fig. 4). For this purpose, in radially outer regions of the spokes 31, in reinforced mouth regions 34 of the spokes 31 to the outer ring 33 out, internal thread running. Alternatively, riveting or pinning may also be considered instead of the screw connection. In addition, instead of the pointwise attachment of the clamping ring 4 with the Radstern 3 also a bond can be selected as a fastener, with releasable connections are preferred. The clamping ring 4 is carried out about the belly 27 according to bulbous, wherein the

Clamping ring 4 the belly 27 radially inwardly almost completely spanned. In an axially outer region is aligned radially outward a sealing ring 42 inserted into the clamping ring 4, which rests radially outwardly against the belly 27. The axially outer flank of the abdomen 27 is not encompassed by the clamping ring 4. In the axially outer region of the clamping ring extends distributed over the circumference with tabs radially inward. In the tabs are

Run through openings through which the screws 5 are feasible. Particularly advantageous sink the heads of the screws 5 in the openings of the tabs. In Figures 5 and 7, a tension of rim 2 and star 3 by means of clamping ring 4 by the screws 5 is shown enlarged. The tension is defined by the geometrical shapes of the components and a first gap 6 between clamping ring and star (in the untensioned state, FIG. 5) and a clamping length, wherein the clamping length is predetermined by a belly width 53 of the stomach 27. By means of the screw 5, the first gap 6 can be closed (Fig. 7), resulting in a bias of the clamping ring 4 results.

The prestress results in a compression of the CFRP bed of the rim 2 selected in the exemplary embodiment and an expansion of the clamping ring 4. A deformation of the star 3 can be neglected due to its design.

In order to bring an optimal biasing force into the system takes into account in the embodiment, the first gap 6 between clamping ring 4 and star 3 manufacturing tolerances. In order to minimize the influence of manufacturing tolerances, the system must be as flexible as possible. This also makes the clamping system insensitive to seating. In the tensioned state and under load - especially when cornering and thus by a lateral force - the bias of the screws on the clamping ring must be so large that the first gap 6 remains closed. Lifting between clamping ring 4 and star 3 is not permitted.

As a result of different operating temperatures in a range between -40 ° C and + 120 ° C it comes due to different thermal expansion coefficients of the individual components to different expansion behavior. This has a direct influence on the tension of the components. The components expand radially and axially, or contract. Decisive for the bias is the expansion component in the axial direction.

For the CFRP bed, a very low to nonexistent thermal expansion coefficient can be assumed. It will simplify only the extent of the star 3 and

Considered clamping ring 4. FIG. 6 illustrates a consideration from which it follows that the belly width 53 depends on a connection angle δ, for which reason it is as small as possible should fail. The connection angle δ is shown in FIG. 7, the angle between a vertical and the course of the edge 51 and the contours 25, 26 in a connection region 52 in a vertical orientation of the wheel 1. An advantageous embodiment of the invention proposes a compromise, as ever greater the connection angle δ, the more flexible is the clamping system and thus its unresponsiveness to setting.

The axial expansion under temperature causes a biasing force loss. Since essentially only the star 3 and the clamping ring 4, but not the rim, axially expands a discharge takes place. At cold temperatures, on the other hand, a preload force increase will be observed. The greater a clamping length resulting from the choice of the belly width 53, the higher the preload force drop with increasing temperature.

Advantageously, the components of the bracing system are designed so that at least approximately correspond to axial and radial bracing. In an advantageous embodiment according to the invention, this is achieved by optimally selecting the connection angle δ, the clamping length 53 and the clamping radius 54. In this way, the clamping system is stable with respect to temperature fluctuations with respect to the prestressing force.

This stability of the prestressing force even at different temperatures is achieved in particular according to the invention in the following manner.

On the other hand, due to the coefficient of thermal expansion of the wheel star 3, or of the outer ring 33, and of the clamping ring 4, for example of the collar 41, the result is substantially no heating of the wheel 1. to an expansion of the spider 3 and the clamping ring 4 both in the radial direction r and in an axial direction.

As can be seen in particular from FIG. 7, both the wheel star 3 and the clamping ring 4 outside the connection region 52 or the flanks 51 are separated by a second gap 56 or a third gap 58 in the radial direction

Belly 27 spaced. Due to the thermal radial expansion or expansion of the clamping ring 4 and the Radsterns 3 at higher temperatures, although it comes to a reduction in the gap size of the second gap 56 and the third gap 58, but a direct contact with the belly 27 in the radial direction is avoided.

However, the thermal expansion of the Radsterns 3 and the clamping ring 4 simultaneously leads to an increase in the axial extent of the same. Due to the formation of the connection angle δ in the region of the connection region 52, however, the respective contact point of the wheel star 3 or of the clamping ring 4 with the rim 2 in the region of the flanks 51 will move radially outwards due to a simultaneous radial and axial expansion. However, the biasing force on the attachment portion 52 of the structure 27 will remain substantially the same in this range due to the inclination δ.

Conversely, shrinkage of the spider 3 and the clamping ring 4 due to thermal shrinkage or compression due to a temperature reduction causes the gap size of the second gap 56 and the third gap 58 to increase due to the radial compression. This causes the point of contact between the hub 3, in particular the outer ring 33, or the clamping ring 4, in particular the collar 41, with the flanks 51 in the connection region 52 moves radially inward. Due to the formation of the connection angle δ and connection region 52, however, a bias voltage is substantially maintained by the fact that the migration of the contact point radially inward just the thermal compression of the wheel hub 3 and the clamping ring 4 is compensated in the axial direction.

This ensures that a maximum voltage is not exceeded during thermal compression and that a minimum voltage is not undershot during thermal expansion.

In a particularly preferred embodiment, as already explained above, the sealing ring 42 is arranged in the region of the second gap 56. By means of the sealing ring 42, however, substantially no force in the radial direction on the rim 2, in particular in the region of the abdomen 27, constructed. The elasticity of the sealing ring 42 merely ensures that the sealing ring 42 remains in contact with the belly 27 and thus prevents foreign bodies, such as dirt or water, from penetrating into the region of the second gap 56 and / or the third gap 58 is avoided without the sealing ring 42 opposes a reduction of the gap 56 a resistance.

Finally, as can be seen from FIG. 7, the clamping ring 4 spans a larger axial area of the stomach 27 compared to the wheel center 3. This achieves, in particular, that the thermal expansion or thermal compression of the wheel star 3 or of the clamping ring 4 is compensated such that a substantially constant bias remains. However, it follows at the same time that the clamping ring 4 is arranged in comparison to known from the prior art wheels on the axially inner side of the wheel 1 and not on the axially outer side to provide sufficient clearance for corresponding braking devices within the wheel 1 , At the same time this results in an optically advantageous embodiment of the wheel 1 in a plan view of axially outside. So in this area just the Radstern 3 is arranged. However, this has no opening or screw on the axially outer side, since they are on the axially inner side on which it is connected by means of the screws 5 with the clamping ring 4, respectively.

The features disclosed in the foregoing description, in the claims and in the drawings may, both individually and in any combination, be essential to the invention in its various embodiments.

LIST OF REFERENCE NUMBERS

1 wheel

2 rim

3 wheel star

4 clamping ring

5 screw

6 first gap 21 rim inside bed

22 Felgenßenbett

23 rim inner horn

24 rim outside horn

25 first circumferential contour 26 second circumferential contour

27 belly

28 survey

29 recess 31 spoke

32 hub area

33 outer ring

34 Mouth area 38 deepening

41 collar

42 sealing ring

51 flank

52 connection area

53 belly width

54 Clamping radius 56 second gap 58 third gap r radial direction δ connection angle

Claims

claims

Wheel (1), in particular partial-alloy wheel and / or light-alloy wheel for motor vehicles, comprising essentially a rim (2) and a wheel center (3),

characterized in that

the wheel star (3) comprises a metal or a metal alloy and the rim (2) comprises a carbon fiber reinforced plastic, the wheel (1) has a clamping ring (4) and the wheel star (3) by means of the clamping ring (4) on the rim (2) is fastened.

Wheel (1) according to claim 1,

characterized in that

the rim (2) has a rim inner bed (21) and a rim outer bed (22) which each transition into a rim inner horn (23) or a rim outer rim (24) and the wheel star (3) in a first circumferential contour (25) is supported axially inside, wherein the first circumferential contour (25) in the outer rim bed (22) or in an axially to the Felgenßenbett (22) adjacent region of the rim (2) is formed.

Wheel (1) according to one of claims 1 or 2,

characterized in that

the clamping ring (4) has a substantially V-shaped or U-shaped cross-section.

Wheel (1) according to one of the preceding claims,

characterized in that

the clamping ring (4) axially inside a radially outwardly formed collar (41) which is supported by a second circumferential contour (26) of the rim (2) axially outward.

Wheel (1) according to one of the preceding claims,

characterized in that

the rim (2) has a bulging belly (27) which bulges radially inward, and contours in the rim (2) are formed with flanks (51) of the belly (27) are, in particular the first circumferential contour (25) and the second circumferential contour (26).

6. wheel (1) according to claim 5,

characterized in that

the flanks (51) with vertical alignment of the wheel (1) in a connection region (52) with respect to the vertical include a connection angle (δ).

7. wheel (1) according to one of the preceding claims,

characterized in that

the clamping ring (4), in particular by means of screws (5), with the rim (2) and / or the wheel center (3) is connectable, in particular in the wheel center (3) can be screwed, wherein in an untensioned state of the clamping ring (4) when the clamping ring (4) is in contact with the rim (2), in a ring area in which the screws (5) are optionally arranged, a first gap (6) between the clamping ring (4) and the rim (2 ) or the wheel star (3) is formed, which is closed in a tensioned state of the clamping ring (4), possibly after tightening the screws (5).

8. wheel (1) according to claim 7,

characterized in that

the star wheel (3) has a multiplicity of spokes (31) which extend in a substantially radial direction (r) starting from a hub region (32) and are provided on the end side in an outer ring (33) which corresponds approximately to an inner diameter of the rim (2) ).

9. wheel (1) according to claims 7 and 8,

characterized in that

the screws (5) are screwed into radially outer regions of the spokes (31), in particular in reinforced mouth regions (34) of the spokes (31) to the outer ring (33).

10. wheel (1) according to one of the preceding claims, characterized in that

the wheel center (3) radially outward and the rim (2) facing elevations (28) and / or depressions (29) and the rim (3) corresponding to many the wheel center (2) corresponding depressions (38) and / or corresponding elevations.

Wheel (1) according to one of the preceding claims,

characterized in that

the clamping ring (4) is formed curved radially inward, so that the clamping ring (4) touches the rim (2) only axially inside with a collar (41), wherein preferably the clamping ring (4), the rim (2) axially outside, when at all, with a sealing ring (42) circumferentially touched.

Wheel (1) according to one of the preceding claims,

characterized in that

the clamping ring (4), in particular the collar (41), outside the flank (51), the connection area (52) and / or outside the second circumferential contour (26), in particular in the radial direction (r), of the Rim (2) is spaced apart by a second gap (56), preferably in the axially outer region, and / or the wheel center (3), in particular the outer ring (33), outside the flank (51), of the connection region (52) and / or outside the first circumferential contour (25), preferably in the radial direction (r), from the rim (2) by a third gap (58), in particular in the axially inner region, is spaced apart.

Wheel (1) according to claim 12,

characterized in that

the second gap (56) and / or the third gap (58) is / are dimensioned such that during an expansion of the clamping ring (4), in particular of the collar (41), and / or of the wheel star (3), in particular of Outer ring (33), in the radial direction (r), in particular an expansion due to a thermal expansion at a predetermined first temperature, a direct contact of the clamping ring (4), in particular the collar (41), and / or the Radsterns (3) , in particular of the outer ring (33), with the rim (2) in the region outside the flank (51), the connection region (52), the first th circumferential contour (25) and / or the second circumferential contour (26) is omitted.

14. Wheel (1) according to one of claims 6 to 13,

characterized in that

the connection angle (δ) is selected so that in the radial direction (r) during a thermal compression of the clamping ring (4), in particular of the collar (41), and / or of the wheel star (3), in particular of the outer ring (33) and / or the axial direction, in particular due to a thermal compression at a predetermined second temperature, the clamping ring (4), in particular the collar (41), and / or the wheel center (3), in particular the outer ring (33), on the flank (51), the first circumferential contour (25), the second circumferential contour (26), in particular in the connection region (52), rests under a bias, wherein the bias voltage is preferably below a predetermined maximum voltage and / or above a predetermined minimum voltage , in particular over an entire temperature range between the second temperature and the first temperature.

15. Wheel (1) according to one of claims 13 or 14,

characterized in that

the first temperature is about 120 ° C and / or the second temperature is about -40 ° C.