Bicycle wheel and drive shaft

Abstract

The present invention relates to a wheel (1) for a bicycle, comprising a rim element (2) made of a thermoplastic plastic material, a plurality of pressure spoke elements (3) and a hub element (4), the rim element (2) being integrally formed with the pressure spoke elements (3) and the hub element (4) on condition that a hollow wheel body (5) with a sealed wheel wall portion (6) is formed, at least the rim element (2) and the pressure spoke elements (3) being hollow, the integral form of the wheel (1) being produced by rotational molding in an externally heatable rotational molding mold, and further comprising a drive shaft for the wheel.

Description

Technical Field

[0001] The present invention relates to a wheel for a bicycle, comprising a rim element made of a thermoplastic plastic, a plurality of pressure spoke elements and a hub element, provided that the rim element is integrally formed with the pressure spoke elements and the hub element.

Background Art

[0002] A generally well-known bicycle wheel composed of a plurality of parts having a standard rim element and standard spokes obtains its strength from the high tensile load-bearing capacity of the standard spokes. These are installed with pretension and are usually made of steel. However, they bend even under low compressive forces.

[0003] This is different from a wheel having pressure spokes in an initial vehicle having a pressure spoke element with a thicker cross-section, for example, a wooden wheel. In principle, the compressive force introduced by the rim element can be absorbed by the pressure spoke element and transmitted to the hub element. The current integrally formed wheel is provided with pressure spoke elements that receive pressure during operation.

[0004] Compared with steel and aluminum, thermoplastic plastics have lower strength as materials for wheels. Its elastic modulus is lower than that of steel and aluminum. Similarly, the dimensional stability of thermoplastic plastics is also low.

[0005] A well-known wheel made of plastic having pressure spoke elements is a so-called composite wheel. This usually consists of a fiber-reinforced plastic reinforced with, for example, a loose fiber component or a fiber fabric, as in, for example, a carbon wheel. When such a wheel is manufactured, stresses and warping can occur during manufacturing. The manufacture of composite wheels is complex and expensive.

Summary of the Invention

[0006] An object of the present invention is to propose a wheel made of a thermoplastic plastic having a simpler structure and manufacturable with high cost efficiency.

[0007] According to the present invention, the object is achieved in that a hollow wheel body is formed by a sealed wheel wall portion, at least a rim element and a pressure spoke element are formed hollow, and the integral nature of the wheel is generated by rotational molding in a rotatable mold capable of external heating.

[0008] The rim element of the hollow wheel body is adapted to allow a normal type of bicycle tire to be installed. In the sense of the present invention, the normal type includes any tubeless tire or tubeless tire with air pressure applied. Furthermore, types of tires occupied by fillers other than air, such as foams having appropriate elasticity during deformation, are also contemplated. The rim element has two rim sides and one rim recess. It is advantageous to provide a rim flange for increasing the force of the bicycle tire on the rim side.

[0009] Regarding rotational molding, the thermoplastic material is injected into the rotatable mold in powder form and is sealed on all sides for the molding process. The rotatable mold has an inner wall, which forms a negative of the shape to be molded. The rotatable mold is preferably formed as a permanent mold made of metal, preferably aluminum. Regarding the molding process, the rotatable mold is rotatable around at least one axis and is externally heated. The plastic powder melts therein and can be dispersed as a viscous melt over the entire inner wall. Finally, the melt solidifies on the inner wall of the rotatable mold and can be removed as the final hollow body when the rotatable mold is opened thereafter.

[0010] The hollow wheel body of a bicycle wheel is required to have a shape with high dimensional accuracy. The inventor has discovered that it is advantageous for the wheel if the plastic material that has already expanded in the mold during solidification can expand freely inwardly into the hollow rotating mold. In this way, a wheel formed with low distortion can be provided, which has the dimensional accuracy and stability required for a bicycle and has very little warping during and after manufacture. Furthermore, the rotationally molded wheel has no seams due to its integral nature, and its strength is increased.

[0011] It is advantageous for the hollow wheel body to have regions of different wall thicknesses in the wheel wall portion. In this way, the hollow wheel body can be adapted such that the points on the wheel wall portion that are particularly stressed during the riding operation are reinforced by additional material to reduce cracking and breakage at these points.

[0012] The regions of the wheel wall portion provided with different wall thicknesses are generated by different external heat inputs into the rotating mold depending on the region. In the regions that are heated more strongly, the powder melts faster and a greater wall thickness can be built up over the course of the process to provide the required strength. Surprisingly, it has been found that low stresses are also possible for a hollow wheel body having different wall thicknesses in the wheel wall portion, which can provide the required dimensional accuracy.

[0013] It is beneficial if the thermoplastic of the wheel wall portion is selected from one of the following plastics: polypropylene (PP), preferably polyethylene (PE), particularly preferably high-density polyethylene (HDPE). An economic cycle in which these plastics can be recycled and provided in a form prepared for reuse already exists for each of the above-mentioned plastics. For this purpose, these plastics are recovered, for example, from the ocean and from agriculture. These plastics are found in fishing nets, bottom trawl nets, nets for aquaculture, or as net wrapping for bundling straw bales, and further as scaffold nets for protecting users on the road. The direct recovery of the above-mentioned plastics from consumer goods that are returned into the cycle without previously polluting the environment is highly promoted in the proposed wheel.

[0014] When the thermoplastic does not contain fibers, it is very suitable for reuse. In the context of the present invention, not containing fibers may also include thermoplastics that are sufficiently low in fibers to be processed so as to be suitable for rotational molding.

[0015] Furthermore, the basic problem is also achieved when each pressure spoke element extends from the hub element to form a stem-shaped base, the stem-shaped base of at least one pressure spoke element extends in the direction of the rim element away from the hub element and is divided into at least two branch elements, and at least one of the branch elements is connected to the rim element.

[0016] During operation, a vertical stress is applied to the bicycle, and as a result, the wheel tends to become slightly flat when contacting the road surface. At the bottom, a compressive force is applied from the road surface direction into the pressure spoke element by the rim element. The pressure spoke element transmits this compressive force to the hub element as much as possible. When the wheel rotates during the riding operation, it is useful that first one of the branch elements reaches and passes through the rotation lowest point before the trunk-shaped base or its center line passes through the rotation lowest point respectively. Immediately when the center line is located at the rotation lowest point, the branch elements are symmetrically arranged, and as a result, both absorb a part of the compressive force acting from below and merge into the trunk-shaped base.

[0017] The design is calculated by software specifically programmed for this purpose, which takes into account the natural growth process. Thereby, the inventor has discovered that it is useful to give the wheel a structure like a stable tree trunk and branches according to the example of nature. The trunk-shaped base can be arranged radially with respect to the hub element for this purpose. The branch elements simply branch from the trunk-shaped base such that the V-shaped configuration of the branch elements is formed towards the rim element. Furthermore, it has been found that it is advantageous if the V-shaped configuration of the branch elements is symmetrically designed.

[0018] The rim element preferably has a nominal rim diameter in the range of 150 mm to 650 mm. The nominal rim diameter is defined as the diameter measured at the lower corner of the rim recess. Thus, for example, a 10-inch wheel has a nominal rim diameter of 152 mm according to ETRTO (European Tyre and Rim Technical Organization), and a 28-inch wheel generally has a nominal rim diameter of 622 mm according to ETRTO.

[0019] The two branch elements of the pressure spoke element and the trunk-shaped base are joined at a node, and the node is located on the diameter of a circle coaxially arranged with respect to the hub element, and it is preferable that the size of the diameter of the circle is in the range of 0.4 to 0.6 times the outer diameter of the rim element.

[0020] The hub element preferably has a hollow cylindrical hub sleeve.

[0021] Furthermore, the wheel also achieves the basic problem when the hub element has a hollow cylindrical hub sleeve and the inner diameter of the hollow cylindrical hub sleeve is at least the same as the length of the hub sleeve in its axial direction.

[0022] This measure is based on the findings of the inventor, and thereby, a relatively large diameter of the hub sleeve with respect to the diameter of the wheel serves to strengthen the wheel. The pressure spoke elements are short to the extent that the radius of the hub sleeve is enlarged.

[0023] Regarding how large the diameter of the drive shaft for the wheel should be, it is considered to be a reference point for the range of the diameter of the hub sleeve when this drive shaft is also made of plastic.

[0024] After consideration, it is considered that a convenient range for the hollow cylinder diameter of the hub sleeve is in the range of 1.0 to 2.0 with respect to the length of the hub sleeve.

[0025] The inventor started from the hollow cylinder diameter of the hub sleeve in the range of 90 mm to 140 mm for an exemplary 28-inch wheel having an outer diameter of 622 mm, ignoring the length of the hub sleeve.

[0026] Furthermore, it is advantageous if the hollow cylindrical hub sleeve of the hub element is optionally adapted to cooperate with either the drive shaft or the fixed wheel axle.

[0027] It is advantageous that at least one means capable of transmitting torque is provided on the hub element.

[0028] In a simple aspect, the means for transmitting torque comprises a plurality of screw holes distributed around the hub sleeve at the edge of the hub element.

[0029] Means for absorbing torque are advantageously adapted to fasten the drive shaft to the hub element and / or to fasten the brake disk to the hub element. The proposed female thread portion at the edge of the hub element can be arranged on a metal element, and it is convenient if the metal element is integrated into the thermoplastic of the hollow wheel body.

[0030] It is useful if a data storage element, preferably an RFID storage element, is provided on the wheel. Preferably, items of material information and / or data regarding the manufacture of the wheel, in particular the plastic material used, can be stored therein. When the bicycle wheel returns to the economic cycle at the end of its life, the stored items of information can help to process and reuse the plastic as a homogeneous raw material.

[0031] In a preferred embodiment, the proposed wheel is provided with six pressure spoke elements.

[0032] It is advantageous if the wheel has an envelope volume in the range of 3.5 liters to 5 liters, preferably in the range of 3.8 liters to 4.4 liters, particularly preferably in the range of 4 liters to 4.2 liters.

[0033] The envelope volume of the wheel in the sense of the present invention means the volume of the outer surface of the wheel (excluding the bicycle tire), provided that all existing openings are interpreted as closed regions of the surface and are due to the outer surface, for example, any opening for a tube valve is interpreted as a closed region of the surface.

[0034] Furthermore, considering the above envelope volume individually or in combination, it is advantageous if the wheel has a weight in the range of 1.3 kg to 2.2 kg, preferably in the range of 1.6 kg to 1.9 kg, particularly preferably in the range of 1.7 kg to 1.8 kg.

[0035] It is convenient if the wheel has a specific gravity in the range of 0.26 kg / liter to 0.63 kg / liter with respect to its envelope volume.

[0036] The present invention further includes the drive shaft for the wheel proposed above. The drive shaft is advantageously adapted for single-sided attachment to a bicycle frame, preferably for single-sided rear wheel support of a bicycle frame.

[0037] It is advantageous if a gear wheel element cooperating with the drive means of the bicycle is arranged on the drive shaft.

[0038] It is advantageous if the gear wheel element comprises a sprocket for a bicycle chain, a detent washer for a toothed belt or a gear wheel for the drive shaft.

[0039] It is advantageous if the drive shaft comprises two shaft elements arranged in a row and connectable.

[0040] It is preferred that one shaft element is configured as a wheel support shaft element and the other as a support shaft element.

[0041] It is advantageous if both shaft elements are provided with complementary connection means adapted to transmit at least one-way rotational movement between the two shaft elements. The connection means can be complementary screw threads or complementary profiles such as spline shaft profiles and spline hub profiles.

[0042] The gear wheel element is preferably arranged on the wheel support shaft element. The wheel support shaft element may be provided with a support element on which the gear wheel element can be rotationally fixedly installed.

[0043] Furthermore, the gear wheel element can be integrated into the drive shaft, or into one of the shaft elements respectively, preferably into the wheel support shaft element.

[0044] A bicycle component is proposed from the group of wheels and drive shafts, the component wall part comprising an integral hollow body surrounding its cavity, the component wall part of the hollow body being manufactured from a thermoplastic in a closed mold, the component wall part having an integral nature produced by rotational molding in an externally heatable mold designed for rotational molding, with a foam being arranged in the cavity, further conditional on the foam extending as a foam layer throughout the interior of the component wall part or completely filling the cavity.

[0045] Finally, another bicycle component is proposed from the group of wheels and drive shafts. This bicycle component comprises a hollow body integral with a component wall part surrounding its cavity, the component wall part of the hollow body being manufactured from a thermoplastic in a closed mold, with the additional conditions that a foam is arranged in the cavity and the foam extends as a foam layer throughout the interior of the component wall part or completely fills the cavity, having an integral nature produced by rotational molding in an externally heatable mold provided for rotational molding.

[0046] The foaming process is advantageously carried out inside the cavity. The foaming process is preferably carried out when the thermoplastic for rotational molding of the component wall part is in a molten state and the rotational molding of the component wall part is still in progress. The starting material of the foam is injected into the cavity-forming part for foaming there using at least one suitable injection means provided in the mold. The starting material is easily injected into the same opening of the mold as the thermoplastic for the component wall part beforehand. A supply pipe insertable into the mold can be used. It can be inserted deep enough to penetrate the layer of molten thermoplastic already formed inside the mold. The injection of the foam starting material can be easily carried out when the rotational movement of the mold is stopped. The rotational movement of the mold is advantageous not only as a circular movement but also as a complex three-dimensional movement in space. To inject the foam starting material, for example, the component of the complex movement can be stopped so that the supply pipe can then be inserted into the injection means of the mold to inject the remaining foam starting material into the cavity.

[0047] In principle, the foaming process may be a physical process, or the foaming process is based on a chemical reaction. It is advantageous if the starting material of the foam is injected in the form of a granular material using the injection means of the mold until it reaches the cavity forming part. For chemical foaming, the granular material of the starting material can be easily provided together with a foaming agent. The foaming agent is preferably designed to be evaporable through heat input. When the starting material also melts through heat input, the evaporated foaming agent can foam the molten starting material.

Brief Description of the Drawings

[0048]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Best Mode for Carrying Out the Invention

[0049] The present invention will be illustrated hereinafter by way of example in the drawings and will be described in detail with reference to several drawings.

[0050] FIG. 1 shows the wheel 1 according to the present invention in a perspective view. The wheel 1 comprises, as components, a rim element 2, a plurality of pressure spoke elements 3 and a hub element 4. The wheel 1 is integrally formed, as a whole, i.e. with all components, in particular by a thermoplastic plastic. It is formed as a hollow wheel body 5 having a closed wheel wall portion 6. In this example, the rim element 2, the pressure spoke element 3 and further the hub element 4 are hollow so that a common cavity 7 is formed. There is no joint in the wheel wall portion 6. The integral nature of the wheel 1 is produced by rotational molding in an externally heatable rotating mold.

[0051] In particular, the pressure spoke element 3 has a specific structure. Each pressure spoke element 3 extends from a trunk-shaped base 3a, in particular from a hub element 4 having a total of six pressure spoke elements 3. They extend radially in the direction from the hub element 4 towards the rim element 2. Each pressure spoke element 3 is symmetrically divided into two branch elements 3b and 3c, so that as a result a total of twelve branch elements are connected to the rim element 2. The proposed structure follows the example of the nature of a tree with a trunk and branches in order to provide improved stability. The symmetrically arranged branch elements 3b / 3c are arranged in a V-shape relative to each other and are adjacent to the rim element 2 at the two ends of the V-shape.

[0052] The wheel shown here has an envelope volume of 4.1 liters with a tolerance of ±0.1 liter. Its weight ranges from 1.6 kg to 1.9 kg.

[0053] The rim element 2 is adapted to receive a conventional type of bicycle tire, such as a pneumatic tire in the form of a tubed tire or a tubeless pneumatic tire. Bicycle tires having a filling other than air, for example, a foam, may be used. These include a deep rim recess 8 and a hollow chamber rim element having rim sides 9 and 10 each having a rim flange (not shown) for fixing the bicycle tire to the rim cross-section.

[0054] Furthermore, the hub element 4 is formed as a large hollow cylindrical hub sleeve 11, and since its inner diameter D is at least the same as the axial length L of the hub sleeve 11, the hub element 4 exhibits a specific structure of this wheel 1. In this example, the inner diameter D of the hub sleeve is 120 mm and its length L is 77 mm. Thus, the hub sleeve 11 is adapted to optionally receive a drive shaft, preferably made of plastic, or to receive a bearing element for attaching the wheel 1 to a fixed wheel axle, preferably made of plastic. Both the wheel axle and the drive shaft require a larger cross-section than a conventional wheel axle or drive shaft made of steel or aluminum. Therefore, the inner diameter D of the hub sleeve 11 is adapted, in particular, to the diameter required by the drive shaft when it is made of plastic. Furthermore, it is considered that the drive shaft can be adapted to be attached on one side, which is achieved by the fact that the wheel 1 is freely accessible from one side and can be installed like an automobile wheel.

[0055] In this example, the inner diameter D of the hub sleeve 11 is 0.7 times larger than the length L of the hub sleeve 11 in its axial direction.

[0056] Figure 2 shows the wheel 1 according to FIG. 1 in a side view. The stable structure of each pressure spoke element 3 can be clearly confirmed. The six pressure spoke elements 3 are uniformly distributed around the hub element 4 and extend radially outwards, with the pressure spoke elements attached to and extending along their stem-shaped base 3a up to a node 12 where the pressure spoke element branches into two branch elements 3b and 3c. Thus, a total of twelve branch elements merge into the rim element 2. The node, in this example, is located on a circle diameter K which is about half of the nominal rim diameter D F of the wheel.

[0057] An RFID storage element 5a is provided in the hollow wheel body 5 to store items of information regarding the wheel 1, in particular information regarding the plastic material used. When the end of its life cycle brings the bicycle wheel back into an economic material cycle, the items of stored information can serve to process the plastic in order to reuse it as a homogeneous raw material.

[0058] Two adjacent pressure spoke elements 3 form a large through-opening 13 together with a part of the rim element 2 and a part of the hub element 4. A total of six large through-openings 13 occur in the wheel 1. Furthermore, each of the two branch elements 3b and 3c of the pressure spoke element 3 forms a small through-opening 14 together with a part of the rim element 2, thereby also forming six small through-openings over the entire wheel 1. In addition to the structural stability, an aesthetically appealing design of the wheel 1 is provided.

[0059] Figure 3 shows a cross-section along the cutting line III-III. The pressure spoke element 3 is cut perpendicular to its radial extent, and the cutting line is arranged slightly inclined with respect to the longitudinal extent of the branch elements 3b and 3c.

[0060] The pressure spoke element 3 is shown enlarged in FIG. 4. The wall thickness t is shown in the cross-section of the pressure spoke element 3 that is filled with a pattern. The filled cross-section constitutes the cross-sectional area of the pressure spoke element 3 that affects the strength according to the material strength theory. The cross-section is formed in a hexagonal shape as an irregular hexagon with different side lengths. The sides facing the axial direction are formed longer than the sides of the hexagonal cross-section arranged parallel to the rotation direction of the wheel. The so-called area moment of inertia of such a cross-sectional area depends on how large the resistance of this cross-sectional area is against external deformation. The shape of the filled cross-sectional area shown here has been found to be convenient for supporting the static vertical load acting on the wheel 1. Further, the filled cross-sectional area is convenient for transmitting torque. On the one hand, it transmits the driving torque when the wheel 1 has to transmit the torque to the road surface as a driven wheel 1, or, for example, when the disc brake is provided on the hub element 4 and the braking torque is transmitted to the hub element 4 via the rim element 2, it is convenient for transmitting the braking torque.

[0061] FIG. 5 is a cross-sectional view of each part of the wheel 1 along the cutting line V-V shown in FIG. 2. The cut extends through the trunk-shaped base 3a of the pressure spoke element 3 and shows the cross-section of the rim element 2. Further, the nominal rim diameter D F is shown. Further, FIG. 5 shows screw holes 15 and 16 having female screw parts provided as means 17 for absorbing torque. As can be best seen in FIG. 8, they are two of a total of six screw holes uniformly arranged on the edge 18 of the hub element 4 for connecting the wheel 1, for example, to a drive shaft. Alternatively, the brake disc can be fastened to the wheel 1 by these screw holes 15 / 16.

[0062] In this example, the screw holes 15 / 16 are arranged in an annular aluminum element 19 integrated into the thermoplastic plastic of the hollow wheel body 5 by rotational molding.

[0063] Figure 6 shows the drive shaft 20 according to the present invention in cross-section. The drive shaft 20 is adapted for single-sided attachment to a bicycle frame, preferably for supporting a single-sided rear wheel of a bicycle frame. The drive shaft 20 comprises two shaft elements 21 and 22 arranged in a row and connectable to each other. One shaft element 21 is designed as a wheel support shaft element 23, and the other is designed as a support shaft element 24.

[0064] The wheel support shaft element 23 has a cylindrical wheel support surface 25 for supporting the wheel according to the present invention shown by a dashed line in Figure 6. The wheel is positioned on the cylindrical wheel support surface 25 together with the hub sleeve of its hub element. Further, the wheel support shaft element 23 comprises a bearing ledge 26 for a roller bearing, also shown by a dashed line. The roller bearing has an inner ring installable on the bearing ledge 26.

[0065] During operation, the inner ring rotates together with the drive shaft 20 and the wheel 1 drawn by a dashed line. The corresponding outer ring of the roller bearing is fixedly arranged on the bicycle frame in the installed state. Further, in this example, a gear wheel element 27 arranged on the wheel support shaft element 23 of the drive shaft 20 is provided. This is formed as a detent washer and is used for a toothed belt capable of transmitting a driving operation to the drive shaft 20.

[0066] The detent washer 28 is rotationally fixedly connected to the wheel support shaft element 23 and is replaceable. Alternatively, the gear wheel element 27 may be integrated with the wheel support shaft element 23 of the drive shaft 20.

[0067] The flange 29 having the through-hole 30 for the screw is provided between the bearing leg 26 and the wheel support surface 25 of the wheel support shaft element 23. The through-hole 30 serves to fasten the drive shaft 20 to the hub element 4 of the wheel 1, and enables the transmission of torque from the drive shaft 20 into the wheel 1 for driving purposes or in the reverse direction, for example, to achieve a braking effect using a brake disk (not shown). A total of six through-holes 30 are provided in the flange 29, uniformly distributed around the flange 29. The arrangement of the six through-holes 30 coincides with the hole pattern of the six screw holes provided at the edge 18 of the hub element 4 of the wheel 1.

[0068] The support shaft element 24 has a cylindrical bearing seat 31 for a roller bearing. This roller bearing is also shown by a dashed line in Fig. 6. Similarly, it is arranged on the bearing seat 31 of the support shaft element 24 and has an inner ring that rotates together with the drive shaft 20 and the wheel 1 during operation. And the corresponding outer ring of this roller bearing is also fixedly arranged on the bicycle frame in the same way.

[0069] The wheel support shaft element 23 is connected to the support shaft element 24. The two shaft elements have complementary profiles as complementary connection means capable of transmitting torque. The wheel support shaft element 23 is provided with a spline shaft profile 32, and the support shaft element 24 is provided with a hub profile 33 that matches it. Further, each of the wheel support shaft element 23 and the support shaft element 24 is provided with a central through-opening 34 and 35, respectively. In a mutually fitted state, the through-openings 34 and 35 are coaxially arranged and can receive a screw connection part (not shown). The two shaft elements 21 and 22 can be connected to each other and axially fixed by a screw connection part including a pressed-in screw and nut.

[0070] Figure 7 shows the wheel 1 according to the invention in cross-section as in Figure 5, but in the installed state on the drive shaft 20 according to Figure 6. The flange 29 of the wheel support shaft element 23 is fastened to the wheel 1 by means of screws 36 and 37. The screws 36 and 37 are pushed into the through-holes 30 of the flange 29 and screwed into the screw holes 15 and 16 respectively at the edge 18 of the hub element 4, thus enabling torque transmission between the drive shaft 20 and the wheel 1.

[0071] Figure 8 shows an enlarged side view of each part of the wheel 1 together with the installed drive shaft 20. In this side view, the six screws 36 and 37 that fasten the flange 29 of the wheel support shaft element 23 to the hub element 4 are confirmed. The hole pattern is arranged such that screw holes are located at each point of the edge 18 of the hub element 4 where the pressure spoke element 3 extends radially outwards.

[0072] Figure 9 shows the wheel 1 as a cross-sectional view of each part along the cutting line IX-IX marked in Figure 2. The hub element 4 is cut at a point away from the pressure spoke element. This figure shows that the hub element 4 is also designed to be hollow. In addition, the wheel axle is drawn in dashed lines by way of example. The wheel axle is fixedly installed on the bicycle frame or on each of its front forks respectively. Further, two roller bearings comprising an inner ring and an outer ring are also shown in dashed lines.

[0073] In this example, the roller bearings are located on the fixed wheel axle together with their inner rings. In contrast, the outer rings are located within the wheel 1, particularly within the hub sleeve 11 of the hub element 4, and as a result, in this example, the outer rings rotate with the wheel 1.

[0074] Figure 10 shows a diagram of an alternative bicycle component. By way of example, the structure of this alternative bicycle component will be described with reference to the area of the pressure spoke element 3 of the wheel as shown in Figure 4. The component comprises a hollow wheel body 5 which is integrally manufactured and has a component wall portion, here a wheel wall portion 6 surrounding a cavity 7. The wheel wall portion 6 is manufactured from a thermoplastic in a closed mold. The integral nature of the wheel wall portion 6 is produced by rotational molding in an externally heatable mold provided for rotational molding. The alternative of Figure 10 differs from the example of Figure 4 in that in this example a foam 40 (foam filling) filling the cavity 7 is additionally arranged in the hollow wheel body 5.

[0075] The foaming process was carried out inside the cavity while the thermoplastic for the wheel wall portion 6 was in a molten state and rotational molding of the wheel wall portion 6 was still in progress. The starting material of the foam was injected into the mold as a granular material by suitable injection means. The granular material used is foamable by a chemical reaction. For this purpose, it contains a blowing agent. In this example, the blowing agent is designed to evaporate through heat input. Through heat input, the starting material is likewise melted and it then foams by the blowing agent which evaporates.

[0076] Figure 11 shows a further example of an alternative bicycle component. By way of example, for this alternative example too, how the alternative bicycle component is configured and how it is manufactured will be described with reference to the wheel. This example is based on the diagram of the wheel of Figure 5. According to Figure 11, the bicycle component is again formed as a component wall portion, in particular a hollow body integral with the wheel wall portion 6, here as a hollow wheel body 5. The wheel wall portion 6 surrounds the cavity 7. It is manufactured from a thermoplastic in a closed mold. The integral nature of the wheel wall portion 6 is again produced by rotational molding in an externally heatable mold provided for rotational molding.

[0077] The alternative example of FIG. 11 is different from the examples of FIGS. 5 and 10 in that in this example, a foam body (foam layer) 41 that covers the component wall portion of this bicycle component, particularly the wheel wall portion 6, is further disposed inside the hollow wheel body 5 facing the cavity 7 (foam layer). As a result, the cavity 7 of the hollow wheel body 5 decreases, but does not disappear in all regions. However, in region 41a, since the cross-section of the cavity 7 is very small, the layer thickness without leaving a cavity becomes the region in this example, and thus, the foam filler 40 is formed in this region.

Explanation of Reference Numerals

[0078] 1 Wheel 2 Rim Element 3 Pressure Spoke Element 3a Trunk-Shaped Base 3b Branch Element 3c Branch Element 4 Hub Element 5 Hollow Wheel Body 5a RFID Storage Element 6 Wheel Wall Portion 7 Cavity 8 Rim Recess 9 Rim Side Portion 10 Rim Side Portion 11 Hub Sleeve 12 Node 13 Through Opening (Large) 14 Through Opening (Small) 15 Screw Hole 16 Screw Hole 17 Means 18 Edge (Hub Element) 19 Annular Aluminum Element 20 Drive Shaft 21 Shaft Element 22 Shaft Element 23 Wheel Support Shaft Element 24 Support Shaft Element 25 Cylindrical Wheel Support Surface 26 Bearing Ledger 27 Gear Wheel Element 28 Lock Washer 29 flange 30 through-hole 31 bearing seat portion 32 spline shaft profile 33 hub profile 34 through-opening 35 through-opening 36 screw 37 screw 40 foamed filler 41 foamed layer 41a foamed filler D inner diameter L length (hub sleeve) D F Nominal rim diameter K diameter of circle (node)

Claims

1. A wheel (1) for a bicycle, comprising a rim element (2) made of a thermoplastic, a plurality of pressure spoke elements (3) and a hub element (4), wherein the rim element (2) is integrally formed with the pressure spoke elements (3) and the hub element (4) on the condition that, a hollow wheel body (5) is formed by a sealed wheel wall portion (6), at least the rim element (2) and the pressure spoke elements (3) are formed hollow, the wheel (1), wherein the integral nature of the wheel (1) is produced by rotational molding in an externally heatable rotary mold.

2. The wheel (1) according to claim 1, wherein the hollow wheel body (5) has regions of different wall thicknesses (t) of the wheel wall portion (6).

3. The wheel (1) according to claim 2, wherein the regions of the wheel wall portion (6) provided with different wall thicknesses (t) are produced by different external heat inputs to the rotary mold depending on the regions.

4. The wheel (1) according to any one of claims 1 to 3, wherein the thermoplastic of the wheel wall portion (6) is selected from one of polypropylene (PP), preferably polyethylene (PE), particularly preferably high-density polyethylene (HDPE).

5. The wheel (1) according to any one of claims 1 to 4, wherein the thermoplastic does not contain fibers.

6. A wheel (1) for a bicycle, comprising a rim element (2) made of a thermoplastic, a plurality of pressure spoke elements (3) and a hub element (4), wherein the rim element (2) is integrally formed with the pressure spoke elements (3) and the hub element (4) on the condition that, each pressure spoke element (3) extends from the hub element (4) to form a stem-shaped base (3a), the stem-shaped base (3a) of at least one pressure spoke element (3) extends in the direction of the rim element (2) away from the hub element (4) and is divided into at least two branch elements (3b, 3c), the wheel (1), wherein at least one of the branch elements (3b, 3c) is connected to the rim element (2).

7. The wheel (1) according to claim 6, wherein the rim element (2) has a nominal rim diameter in the range of 150 mm to 650 mm.

8. The two branch elements (3b, 3c) of the pressure spoke element (3) and the stem-shaped base (3a) are joined at a node (12), the node (12) being located on the diameter (K) of a coaxial circle with respect to the hub element (4), The size of the diameter (K) of the circle is in the range of 0.4 to 0.6 times the nominal rim diameter (D Ｆ ) of the rim element (2), the wheel (1) according to claim 7. **Claim 9** The hub element (4) has a hollow cylindrical hub sleeve (11), the wheel (1) according to any one of claims 1 to 8. **Claim 10** A wheel (1) for a bicycle, comprising a rim element (2) made of a thermoplastic, a plurality of pressure spoke elements (3) and a hub element (4), provided that the rim element (2) is integrally formed with the pressure spoke elements (3) and the hub element (4), the hub element (4) having a hollow cylindrical hub sleeve (11), the inner diameter (D) of the hollow cylindrical hub sleeve (11) being at least the same as the length (L) of the hub sleeve (11) in its axial direction, the wheel (1). **Claim 11** The range of the inner diameter (D) of the hub sleeve (11) is in the range of 1.0 to 2.0 times the length (L) of the hub sleeve (11), the wheel (1) according to claim 10. **Claim 12** The hollow cylindrical hub sleeve (11) of the hub element (4) is optionally adapted to cooperate with either a drive shaft (20) or a fixed wheel axle, the wheel (1) according to claim 10 or 11. **Claim 13** At least one means (17) capable of transmitting torque is provided on the hub element (4), the wheel (1) according to any one of claims 10 to 12. **Claim 14** The means (17) for transmitting the torque comprises a plurality of threaded holes (15, 16) distributed around the hub sleeve (11) at an edge (18) of the hub element (4), the wheel (1) according to claim 13. **Claim 15** The means (17) for absorbing torque is adapted to fasten a drive shaft (20) to the hub element (4) and / or to fasten a brake disc to the hub element (4), the wheel (1) according to claim 13 or 14. **Claim 16** The threaded holes (15, 16) are arranged in a metal element at the edge (18) of the hub element (4), the metal element being integrated into the thermoplastic of the hollow wheel body (5), the wheel (1) according to claim 14 or 15. **Claim 17** The wheel (1) according to any one of claims 1 to 16, provided with six pressure spoke elements (3).

18. A drive shaft (20) for a wheel (1) according to any one of claims 1 to 17, wherein the drive shaft (20) is adapted for attachment to one side of a bicycle frame, preferably for attachment to one side rear wheel support of a bicycle frame.

19. The drive shaft (20) according to claim 18, in which a gear wheel element (27) capable of cooperating with a drive means of a bicycle is arranged.

20. The drive shaft (20) according to claim 19, wherein the gear wheel element comprises a sprocket for a bicycle chain, a detent washer (18) for a toothed belt or a gear wheel for a drive shaft.

21. The drive shaft (20) according to any one of claims 18 to 20, wherein the drive shaft (20) comprises two shaft elements (23, 24) arranged in a row and connectable.

22. The drive shaft (20) according to claim 21, wherein one shaft element is configured as a wheel support shaft element (23) and the other is configured as a support shaft element (24).

23. The drive shaft (20) according to claim 21 or 22, wherein both shaft elements are provided with complementary connection means (32, 34) adapted to transmit a rotational movement at least between the two shaft elements.

24. The drive shaft (20) according to claim 22 or 23, wherein the gear wheel element (27) is arranged on the wheel support shaft element (23).

25. The drive shaft (20) according to any one of claims 20 to 24, wherein the gear wheel element (27) is integrated.

26. A bicycle component from a group of wheels and drive shafts, comprising an integral hollow body (5) with a component wall part (6) surrounding its cavity (7), the component wall part (6) of the hollow body (5) being manufactured from a thermoplastic plastic within a closed mold, the component wall part (6) having an integral property generated by the rotational molding in an externally heatable mold designed for rotational molding, a foam being disposed within the cavity (7), with the additional condition that the foam extends at least partially as a foam layer (41) across the entire interior of the component wall part (6) or completely fills the cavity (7) as a foam filling (40, 41a) at least in regions.

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