Motorcycle wheel

Abstract

The present invention relates to a motorcycle wheel (1) with a rotation axis (2) with a wheel center (3) made of fiber-reinforced material and a circumferential rim (4). The wheel center (3) comprises a hub (5) and a plurality of spokes (6) extending from the hub (5) to the circumferential rim (4), and a shell-like mounting structure (7) for mounting of a break disc to the wheel center (3). The mounting structure (7) comprises an outer wall (9) encompassing at least partially an inner space (8) and has a star-like cross-section when viewed in the direction of the rotation axis (2) with at least three star tips (11) extending in outward direction.

Description

[0001] Motorcycle wheel

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to a motorcycle wheel.

[0004] BACKGROUND OF THE INVENTION Motorcycle wheels play a critical role in the overall dynamic performance of a motorcycle. Specifically, their weight has a direct influence on handling, suspension response, and the overall maneuverability and riding experience.

[0005] To address weight concerns, traditional steel wheels have given way to modern alternatives made from lightweight alloys or even fiber-reinforced materials. Next to weight reduction, wheel designs also focus on providing adequate torsional stiffness. In addition, the lightweight structure should provide solid mounting points, often standardized in position, for the wheel itself or other accessories such as the brake disc. However, these requirements often conflict with lightweight design objectives. An example of a motorcycle wheel is given in W02018073005A1 , published in 2018 on behalf of the same applicant, which discloses a motorcycle wheel having a wheel center made of a fiber-reinforced composite material. Here, separate flange rings are interconnected on both sides to a tubular middle section of the wheel center to attach the wheel and provide further mounting points. It is an object of the invention to provide a light motorcycle wheel with a good torsional stiffness.

[0006] SUMMARY OF THE INVENTION

[0007] The present invention relates to a motorcycle wheel with superior performance I weight ratio compared to wheels known from the prior art. This is achieved by an improved shell-like structure especially in the region of the wheel center. The technology of the motorcycle wheel according to the invention may be implemented as a front wheel with a break disc on only one side or opposite to each other on both sides of the wheel or as a back wheel with a drive gear on one side and a break disc on the opposite side.

[0008] The motorcycle wheel has a wheel center and a circumferential rim. The rim extends around a rotation axis (also: axis of rotation) of the motorcycle wheel. The wheel center comprises a hub and a plurality of spokes extending from the hub to the circumferential rim. At the outer end of the spokes, the spokes may be interconnected to the rim or formed integrally with the same. In context of this disclosure, interconnected is understood as directly connected or indirectly connected via at least one further part of the motorcycle wheel. At an inner end of the spokes the spokes can be formed integrally with the hub.

[0009] To provide a light structure, at least the wheel center is made (at least partially or fully) of fiber-reinforced material. However, also the rim may be made of fiber- reinforced material. The fiber-reinforced material may thereby be arranged as a shell like structure. Advantageously, the fiber-reinforced material comprises layered fiber plies embedded in a matrix material, such as resin. These layers form the shell like structure, if present. For a particular strong but light structure, the fiber-reinforced material may comprise at least one stitched fiber structure. Such stitched fiber structures can e.g. be manufactured by multi-axial warp knitting or by TFP (Tailored Fibre Placement) and are particularly advantageous to provide out-of-plane stiffness and strength and significantly improve three-dimensional stress conditions. The stitched fiber structure may be embedded in the same matrix material as the layered fiber plies. The stitched fiber structure can thereby comprise a three-dimensional network of fiber strands. If appropriate, unidirectional fiber strands can be integrated into the stitched fiber structure. The use of plies and / or stitched fiber structures thus provide an overall stronger structure in comparison to e.g. wheels made of disconnected short fibers embedded in plastic material.

[0010] The wheel according to the invention further comprises a mounting structure for mounting of a break disc to the wheel center with screw holes arranged on the mounting structure to receive fastening bolts for fastening of the break disc. Preferably, the mounting structure is an integral part of the wheel center made. Therefore, the mounting structure is advantageously (at least partially or fully) made of fiber-reinforced material. In contrast to conventional wheels, where the mounting structure is usually integrated into a metal insert that spans and covers a larger area of the wheel center, an integral design of the mounting structure within the fiber-reinforced material results in a much lighter wheel design. The mounting structure according to the present disclosure comprises an outer wall extending, in particular integrally, from the spokes and / or the hub in the direction of the axis of rotation and merging into an end face of the mounting structure. The extension of the mounting structure from the spokes and / or the hub allows for sufficient space for e.g. brake pads arranged between the spokes and the break disc. In a mounted position of the break disc, the end face is oriented towards the brake disc, which is preferably arranged on the end face. The outer wall adjacent to the end face preferably has a rotationally symmetric design with respect to the axis of rotation of the wheel. Under rotationally symmetric design is understood that the shape of the outer wall coincides with itself after a rotation with an angle less than 360°. Such a design allows for an easy mounting of the break disc. The outer wall merges at a proximal end - with respect to a central plane of the wheel - into the hub and / or the spokes. The central plane is thereby perpendicular to the axis of rotation and located at the center of the wheel. At a distal end of the outer wall, the outer wall merges into the end face (wherein the proximal end of the outer wall is closer to the central plane than the distal end). The end face may be three- dimensionally shaped, e.g. in that it is not flat and comprises itself protrusions and depressions or stiffening ribs. Depending on the application, a central portion of the mounting structure may have a greater distance from the central plane of the wheel center than a radially outer portion of the end face.

[0011] A cross-section of the outer wall of the mounting structure is preferably star-like when viewed in the direction of the axis of rotation with at least three star tips extending in outward direction. Thereby, the screw holes for fastening of the break disc are advantageously arranged in the outer region of the star tips. This placement and structural design of the outer wall allows for an arrangement of the screw holes at a greater distance from the axis of rotation while providing good structural stiffness. In contrast, when screw holes in conventional metal inserts are placed at a similarly greater distance from the axis of rotation, the greater distance inevitably adds unnecessary weight to the wheel.

[0012] Next to the outer wall, also the end face can be star-like. Thus, a mounted break disc is only partially arranged next to the end face as the break disc is exposed between the star tips to a cooling space allowing for an improved air circulation around the break discs and thus resulting in a better cooling of the same.

[0013] For better structural stiffness, the outer wall may be rounded around the star tips and / or the transitional portions between adjacent star tips. Advantageously, the star tips of the mounting structure are aligned with the spokes of the wheel center. E.g. if the spokes extend in the radial direction in a respective extension direction of a spoke, the star tip arranged on that spoke may point in said extension direction. The star tips are preferably arranged at the center of the respective spokes if viewed from the direction of the axis of rotation. If the spokes are curved in the radial direction, other arrangements of the star-like structure are possible. Depending on the application, the number of star tips can be identical to the number of spokes. Hence, depending on the wheel design, the mounting structure may feature e.g. five or six star tips.

[0014] For a lightweight design, the motorcycle wheel preferably comprises an inner space. The inner space may be hollow or filled at least partially with a filler material, such as e.g. foam or a honeycomb structure. Preferably, the mounting structure encompasses at least partially the inner space. To form the inner space, the mounting structure may be shell-like with a comparably thin wall thickness. The shell of the mounting structure may thereby comprise fiber-reinforced material, in particular multiple layers of fiber plies embedded in a matrix material. Preferably, a cross section of the inner space within the mounting structure increases in the direction of the axis of rotation and towards the central plane of the wheel center. Advantageously, the inner space further extends at least partially from the mounting structure into the hub and optionally from the hub into the spokes. However, the inner space can also extend from the mounting structure directly into the spokes.

[0015] Due to the complex geometry, the inner space is preferably designed such that it can be manufactured by a resolvable core. Therefore, cross sections of respective parts of the inner space of the mounting structure and / or the hub and / or the spokes preferably widen towards transition areas between the hub and the spokes and / or between the mounting structure and the hub and / or between the mounting structure and the spokes. Such a designs allows for an easy removal of the core with as little core residue as possible.

[0016] To provide solid mounting points for the fastening bolts, the screw holes may be arranged in fastening inserts of the motorcycle wheel. Using fastening inserts can further prevents corrosion between the fiber-reinforced material and the fastening bolts. The respective fastening inserts are thereby each located in the radial direction a distance apart from the central axis and spaced apart from each other. The fastening inserts can each comprise a bushing that forms the respective screw hole. The bushing may thereby extend over the whole length of the outer wall of the mounting structure in direction of the axis of rotation. The outer wall may circumvent the bushing at least partially. Hereby, the outer wall can be spaced a distance apart from the bushing. Hence, parts of the inner space may be arranged in the radial direction between the bushing and the outer wall. Alternatively, the bushing may be circumvented by the outer wall (with no inner space arranged between the bushing and the outer wall). Furthermore, the outer wall may form at least partially a dome around said bushing, as explained in more detail below.

[0017] Depending on the application, an outer side of the bushing may be at least partially conically shaped. Hereby the outer circumference of the conically shaped bushing may decline towards the central place of the wheel center. Alternatively, also a hollow cylindrical bushing is possible. Furthermore, the fastening insert may comprise a collar abutting (with a backside of the collar) against the end face of the mounting structure to prevent slipping of the fastening insert into the inner space. On the circumference of the busing and next to the collar, a groove may be present into which the fiber strands and / or the stitched fiber structure engages. For fastening of the break disc, the fastening inserts may further feature, in particular on a front side of the collar, an attachment interface circumventing the screw holes. Advantageously, the attachment interface is spaced a distance apart from the end face of the mounting structure. The fastening insets can be made at least partially from a solitary material, such as metal or ceramic. Alternatively or in addition, a heat insulating material may be used.

[0018] Depending on the embodiment, the fastening inserts and in particular, the respective bushings of the fastening inserts can extend into the inner space. Hence, the inner space circumvents the bushing at least over a part of a length of the bushing. In some applications, the inner space may thereby circumvent the bushing over the majority of the length of the bushing, over even over more than 75% of the length of the bushing.

[0019] Depending on the application, the wheel center may have a central opening arranged in the mounting structure. The central opening can at least partially accommodate at least one central insert. The at least one central insert serves to receive an axle of the motorcycle wheel. Thus, the central insert may comprise a through opening extending through the respective central insert. Furthermore, the at least one central insert may comprise a bearing seat for a bearing for the axle of the motorcycle wheel. The bearing seat may be arranged in the through opening. The at least one central insert can further comprise an outer flange part. The outer flange part preferably abuts (with a backside of said flange part) against the respective end face of the mounting structure. Furthermore, the at least one central insert may comprise an inner flange part, as explained in more detail below. In direction of the axis of rotation, the inner flange part can hereby be arranged closer to the central plane of the wheel than the bearing seat. There may further be a shoulder of the central insert arranged in direction of the axis of rotation between the bearing seat and the inner flange part to act as an axial stop for the bearing.

[0020] Depending on the application, the motorcycle wheel can comprise two central inserts each arranged at least partially within the central opening. The respective central inserts can hereby be arranged opposite each other with respect to the hub. Advantageously, the two central inserts are connected with each other either directly or indirectly. This connection serves for a more stable force transmission in particular during manufacturing, more particular during pressing of the bearing into the bearing seat. A very stable setup is achieved if the two central inserts are directly or indirectly connected with each other in addition to one or multiple fastening inserts being connected with each other through the inner space, as explained in more detail below. In case of a direct connection of the two central inserts, the inserts may be clamped to each other to avoid noise during use. Alternatively or in addition, also other connections such as screw connections and / or adhesive can be used. In case of an indirect connection of the two central inserts (first and second central insert), the (first and second) central inserts can be connected to each other via a connection element. The connection element may be clamped to the respective central inserts to avoid noise during use. Alternatively or in addition, also other connections such as screw connections and / or adhesive can be used.

[0021] The connection element may be arranged in the direction of the axis of rotation between the respective central inserts. Hence, the connection element extends through the wheel and in particular through the inner space. In radial direction, the connection element can thus be circumvented partially or fully by the inner space. Preferably the connection element is circumvented at least over 80% of its length (in direction of the axis of rotation) by the inner space.

[0022] Depending on the application, the connection element may at least partially have a hollow cylindrical shape in direction of the axis of rotation. Thereby the respective central insert can be arranged with the inner flange part within a respective end of the connection element. Hence, the first central insert may be arranged with the inner flange part within a first end of the connection element and / or the second central insert may be arranged with the inner flange part within a second end of the connection element. Alternatively, the first or second end of the connection element can be received in the through opening. If applicable, the first and / or second end of the connection element received in the through opening of one of the central inserts may serve as the shoulder to act as an axial stop for the bearing.

[0023] Depending on the application, a groove may be present on the circumference of the central insert. In particular the groove may be arranged next to the outer flange part. The fiber strands and / or the stitched fiber structure may further engage into said groove of the central insert. On the outer flange part, further attachment points for mounting an axle of the motorcycle wheel may be present. Preferably, the attachment interface, as described above, is closer to the central plane than a front face of said outer flange part. The distance of the attachment interface to the end face serves to make the mounted brake disc more accessible. Furthermore, the central insert can also extend into the inner space and / or be at least partially circumvented by the inner space. If the inner space is designed such that it can be manufactured by a resolvable core, the resolved core material can be removed through the central opening. In case of star-like outer wall and / or end face, an outer contour of the star tips of the outer wall essentially extends tangential from the central opening.

[0024] For further structural stiffness, one or multiple stiffening ribs may be arranged on the end face. One stiffening rib can e.g. be arranged circumventing the central opening and / or the outer flange part of the central insert. Alternatively or in addition the star tips may by framed by the stiffening ribs arranged on the end face. These stiffening ribs may extend tangential from the central opening. Additional stiffening ribs may frame transitional regions of the end face between adjacent star tips. Depending on the design, the height of the stiffening ribs can vary. Preferably, the stiffing ribs around the start tips decline in height towards the respective start tips.

[0025] Depending on the application, the fiber-reinforced material of the mounting structure may comprises fiber strands, in particular unidirectional fiber strands, circumventing at least partially or fully the central opening and / or the fastening openings. The respective fiber strands may be arranged in a stitched fiber structure. The stitched fiber structure can thus at least partially circumvent the central opening and / or the screw holes, respectively the fastening openings (e.g. in the respective grooves if present). Preferably, the stitched fiber structure comprises loops, each loop circumventing at least partially a respective fastening opening. The loops are interconnected to the part of the stitched fiber structure circumventing partially of fully the central opening. Depending on the application, the stitched fiber structure, respectively the fiber strands may be arranged on or in a walling of the mounting structure formed by layered fiber plies of the reinforced fiber material. E.g., the stitched fiber structure and / or the fiber strands may be arranged on an inner side or an outer side of the (layered) walling. If the stiffening ribs (as described above) are present, the fiber strands may be arranged aligned to said stiffening ribs.

[0026] Depending on the application, the fastening inserts may be connected to each other through a cover. The cover can be attached, in particular glued, to at least parts of the end face. Preferably, the cover fully covers the end face and may even extend around the corners of the end face to cover the distal end of the outer wall. Hence, the bushings of the fastening inserts extend from a backside of the cover and in direction of the axis of rotation. The cover can also be made from same solitary material as the fastening inserts. The cover may e.g. be forged. In case a cover is used, it may be advantageous that a shell-like mounting structure also comprises domes circumventing partially or fully the bushings.

[0027] A preferred variation of the motorcycle wheel comprises a shell-like mounting structure for mounting of a break disc to the wheel center with screw holes arranged in the outer region of the star tips to receive in a mounted position a fastening bolt. The outer wall of said mounting structure encompasses the inner space and has a star-like cross-section when viewed in the direction of the axis of rotation with at least three star tips extending in outward direction.

[0028] Depending on the application, the motorcycle wheel may comprise two mounting structures (according to the variation as outlined above) arranged opposite of each other with respect to the hub. This is in particular advantageous, if the motorcycle wheel is a front wheel. The two mounting structures may be mirrored at the central plane but be identical in design. However, also different designs of the two mounting structures may be chosen. Preferably, the two mounting structures (first and the second mounting structure) are both star-like, wherein the outer walls are aligned to each other. Alternatively or in addition, the fastening inserts as well as the center inserts arranged on the first side and the second side are advantageously arranged coaxially to each other.

[0029] A stable structure may be achieved, if the fastening inserts arranged on the first and second mounting structure are aligned coaxially and interconnected to each other, in particular through the inner space. Hereby the (first) fastening inserts from a first side of the wheel center may comprise an outer thread and the (second) fastening inserts from an opposite second side of the wheel center may comprise an inner thread designed to engage with the respective outer threads (or vice versa). For mounting the (first and / or second) fastening inserts with respect to each other, the (first and / or second) fastening inserts may have tool interface. The tool interface can e.g. be located at a base of the screw hole for inserting a tool and / or on the outer circumference of the bushing. Also, for the interconnected fastening inserts, the outer side of the respective bushings may be shaped conically, as explained above. Alternatively or in addition to the screw interconnection, the first and second fastening inserts may be adhered to each other, in particular in the region of the screw interconnection.

[0030] Alternatively, the coaxial fastening inserts may each be interconnected by a spacer. The spacer may be a bushing with one or two inner threads designed to engage with respective threads on the coaxial fastening inserts. In an alternative embodiment the respective fastening insert may be extend through the wheel center featuring on both ends a screw hole for attaching a break disc on both sides. Also, the screw interconnections of the spacer to the respective fasting inserts may be strengthened by using a further adhesive.

[0031] Depending on the application, it may be advantageous, if the mounting structure comprises domes extending at least partially around the respective fastening inserts and extending from the inner side of the mounting structure in the direction of the axis of rotation. The inner side of the mounting structure is hereby opposite of the end face with respect to the shell-like wall of the mounting structure. The domes can extend from the inner side of the mounting structure into the inner space to each accommodate at least partially or fully one of the fastening inserts. In the mounted position, the domes can circumvent partially or fully the respective fastening inserts. The domes thereby offer further stability to the mounting structure. The domes may also be shell-like. The domes may be cylindrical or feature at least one conical section, with the smallest diameter being located in the central plane of the wheel center. Alternatively, or in addition, the outer wall of the mounting structure may circumvent the fastening insert and in particular the bushing at least partially forming parts of the dome. Thus, the dome circumvents and abuts against the fastening insert and in particular the bushing at least partially in the direction of the axis of rotation. Equivalently, a further (central) dome may be arranged at least partially around the central insert(s). If two coaxial and interconnected fastening inserts are used with respective domes circumventing the interconnected fastening insets fully, the first and second mounting structures are thus interconnected to each other by said domes extending through the inner space and adding further stiffness to the structure.

[0032] As stated above, also the hub and / or the spokes may be shell-like encompassing partly the inner space. The shell-like hub may thereby comprise multiple hub wall segments, wherein each hub wall segment connects two adjacent spokes with each other. Depending on the design, the hub wall may also circumvent the rotational axis featuring per spoke a mouth into the inner space of the respective spokes. The respective hub wall or hub wall segments may merge into the outer wall of the mounting structure. It is to be understood that both the foregoing general description and the following detailed description present embodiments and are intended to provide an overview or framework for understanding the nature and character of the disclosure. The accompanying drawings are included to provide a further understanding and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments, and together with the description serve to explain the principles and operation of the concepts disclosed.

[0033] BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The herein described invention will be more fully understood from the detailed description given herein below and the accompanying drawings that should not be considered limiting to the invention described in the appended claims. The drawings are showing:

[0035] Fig. 1 A first variation of the motorcycle wheel according to the invention in a partially sectionized and perspective view; Fig. 2 The wheel according to Figure 1 in a front view.

[0036] Fig. 3 A sectionized view A - A according to Figure 2 illustrating the fastening inserts.

[0037] Fig. 4 A first variation of an alternative setup of the fastening inserts;

[0038] Fig. 5 A second variation of an alternative setup of the fastening inserts; Fig. 6 A second variation of the motorcycle wheel according to the invention in a perspective view;

[0039] Fig. 7 A third variation of the motorcycle wheel according to the invention in a perspective and partially sectionized view;

[0040] Fig. 8 A detail of the variation of the motorcycle wheel according to Fig. 7 in a sectionized view;

[0041] Fig. 9 A fourth variation of the motorcycle wheel according to the invention in a sectionized view.

[0042] DESCRIPTION OF THE EMBODIMENTS

[0043] Reference will now be made in detail to certain embodiments, examples of which are illustrated in the accompanying drawings, in which some, but not all features are shown. Indeed, embodiments disclosed herein may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Whenever possible, reference numbers will be used to refer to like components or parts.

[0044] Figure 1 - Figure 3 show a first variation of a motorcycle wheel 1 according to the invention. The motorcycle wheel 1 comprises a wheel center 3 and a circumferential rim 4 extending around a rotational axis 2. The wheel center 3 comprises a hub 5 and a plurality of spokes 6 extending from the hub 5 to the circumferential rim 4. The wheel center 3 further comprises a mounting structure 7 arranged on the hub 5 and the spokes 6. Preferably, the wheel center 3 and the rim 4 are connected integrally and both comprise fiber-reinforced material.

[0045] The mounting structure 7 is shell-like and encompasses at least partly an inner space 8 of the motorcycle wheel 1 . The inner space 8 further extends into the hub 5 and into the spokes 6. Therefore, also the spokes 6 and the hub 5 can thus be designed shell like, as shown. The mounting structure 7 comprises an outer wall 9 extending around the rotational axis 2. Hereby, the outer wall 9 merges at a proximal end into the hub 5 and the spokes 6 and at the distal end into the end face 10. The outer wall 9 has a star-like cross-section when viewed in the direction of the rotation axis 2 with at least three star tips 11 extending in outward direction. In the shown variation, five star tips 11 are present. Respectively, the end face 10 is also star-like when viewed in the direction of the axis of rotation 2.

[0046] A central opening 18 as well as multiple fastening openings 14 are arranged in the end face 10. The fastening openings 14 are preferably arranged in the outer region of the star tips 11 . Furthermore, multiple stiffening ribs 20 may be located on the end face 10. Wherein the central opening 18 serves to receive a central insert 17, the fastening openings 14 each serve to receive a fastening insert 13 to attach the break disc. The central insert 17 and / or a bushing 15 of the respective fastening inserts 13 extend in the direction of the axis of rotation 2. The central insert 18 further comprises an outer flange part 28 abutting against the end face 10. Furthermore, the fastening insert each comprises a collar 16 to abut against the end face 10. The bushings 15 further circumvent a screw hole12 to receive a fastening bolt in a mounted position. The bushings 15 may be conically shaped, as can be seen in Figure 1 and Figure 3. Hereby the outer circumference of the conically shaped bushing 15 declines towards a central plane 27 of the wheel center 3.

[0047] However, depending on the application, other designs of the fastening inserts 13 are possible, as shown in Figure 4 and Figure 5. If e.g. two mounting structures on opposite sides of the wheel center 3 are present, the fastening inserts 13a arranged in the first mounting structure and fastening inserts arranged in the second mounting structure 13b may be aligned coaxially with respect to each other. Furthermore, the coaxial fastening inserts 13a, 13b can be interconnected to each other, as it is illustrated in Figure 4. Hereby the fastening inserts 13a from one side of the wheel center 3 each comprise an outer thread 22 and the fastening inserts 13b from the opposite side of the wheel center 3 each comprise an inner thread 23 designed to engage with the respective outer threads 22 (or vice versa). In an alternative embodiment illustrated in Figure 5, the respective fastening inserts 13 may be extend through the wheel center 3 featuring on both ends a screw hole 12 for attaching a break disc. In each variation, the shell-like mounting structure 7 may extend around the respective fastening inserts 13. Hence, for the variations shown in Figure 4 and Figure 5, the first and second mounting structures 7a, 7b can be interconnected to each other by domes 26 circumventing the fastening inserts 13. However, also variations are possible, where the domes only partially circumvent the respective fastening inserts 13 (with the domes not interconnecting the first and second mounting structures 7a, 7b). Figure 6 shows a second variation of a motorcycle wheel 1 according to the invention. The second variation differs from the first variation in that the fastening inserts 13 (of one side of wheel center 3) are connected to each other by a cover 25. The cover 25 is attached to the end face 10 of the mounting structure 7 and covers the end face 10 and preferably the distal end of the outer wall 9. Furthermore, for each screw hole, the fastening inserts may comprise collar with an attachment interface extending beyond an outer face of the cover. The cover 25 further features a central cut out, such that the central opening 18 of the wheel center 3 is assessable. Furthermore, the shell-like mounting structure 7 may also comprises shell-like domes 26 circumventing partially or fully the fastening inserts 13 interconnected by the cover 25.

[0048] Figure 7 and Figure 8 illustrate a third variation of a motorcycle wheel 1 according to the invention. The motorcycle wheel 1 comprises a wheel center 3 and a circumferential rim 4 extending around a axis of rotation 2. The wheel center 3 comprises a hub 5 and a plurality of spokes 6 extending from the hub 5 to the circumferential rim 4. The wheel center 3 further comprises a mounting structure 7 arranged on the hub 5 and the spokes 6. Preferably, the wheel center 3 and the rim 4 are connected integrally and both comprise fiber-reinforced material.

[0049] The mounting structure 7 is again shell-like and encompasses at least partly an inner space 8 of the motorcycle wheel 1 . The inner space 8 also extends into the hub 5 and into the spokes 6. Therefore, also the spokes 6 and the hub 5 can thus be designed shell like, as shown. The mounting structure 7 comprises an outer wall 9 extending around the rotational axis 2. Hereby, the outer wall 9 merges at a proximal end into the hub 5 and the spokes 6 and at the distal end into the end face. The outer wall 9 has a star-like cross-section when viewed in the direction of the rotation axis 2 with at least three star tips 11 extending in outward direction. A central opening 18 as well as multiple fastening openings are arranged in the end face.

[0050] The fastening openings each serve to receive a fastening insert 13 to attach the break disc. The fastening openings are preferably arranged in the outer region of the star tips 11 . Stiffening ribs 20 may be located on the end face. A bushing 15 of the respective fastening inserts 13 extends in the direction of the axis of rotation 2. Furthermore, the fastening insert 13 each comprises a collar 16 to abut against the end face 10. The bushings 15 further each circumvent a screw hole 12 to receive a fastening bolt in a mounted position. Depending on the application, two mounting structures 7 on opposite sides of the wheel center 3 can be present. Hereby, the fastening inserts 13 in the first and second mounting structure 7 can be arranged coaxially and interconnected with each other, as explained in context with Figure 4. In the variation according to Figure 8, the domes 26 however only partially circumvent the respective fastening inserts 13. Hence, the domes 26 do not interconnect the first and second mounting structures 7a, 7b. The respective domes 26 extend from the end face 10 of the mounting structure 7 into the inner space 8. In the shown variation, inner space remains partially between the respective domes 26 and the outer wall 9. However, this region may also be filled with fiber reinforced material.

[0051] The central opening 18 serves to receive at least one central insert 17. In the shown variation, two central inserts 17 are arranged within the central opening 18 opposite each other with respect to the hub 5. The respective central inserts 18 further each comprises an outer flange part 28 abutting against the respective mounting structures 7 arranged on both sides of the wheel 1 . The central inserts 17 further both extend at least partially in the direction of the axis of rotation 2. Depending on the application the central insert 17 may extend at least partially into the inner space and / or may be circumvented by a central dome 26. The central inserts may further be directly connected to each other or, as shown, indirectly connected to each other via a connection element 29. The connection element 29 is hereby interconnected with a first end to the first central inserts 17 and with the second end to the second central insert 17. For the interconnection the respective first or second end of the connecting element 29 may be received on a respective inner flange part of the central insert 17 (as shown) or received in a respective though opening of the central insert 17.

[0052] Figure 9 illustrates a fourth variation of a motorcycle wheel 1 according to the invention in a sectionized view (only upper half of the wheel displayed). The setup of the motorcycle wheel 1 is essentially the same as the variation of the motorcycle wheel 1 as explained with respect to Figure 8. However, as can be seen the individual geometry of the hub 5 and the spokes 6 as well as the circumferential rim 4 is slightly different. In the shown variation, the domes 26 around the fastening inserts 13 are further formed partially by the outer wall 9 of the mounting structure 7. Furthermore, a wedge-like central dome 26 of fiber reinforced material is arranged around the central insert 17 to stabilize and mount the same. The respective domes 26 around the fastening inserts 13 and the central dome 26 both extend from the end face 10 of the mounting structure 7 into the inner space

[0053] 8. The shell-like mounting structures 7 of the respective variations can comprise multiple layers of fiber plies embedded into a matrix material forming a layered walling. Depending on the application, the fiber-reinforced material of the shelllike mounting structure 7 may further comprises fiber strands 21 , in particular unidirectional fiber strands. Preferably, the fiber strands 21 circumvent at least partially the central opening 18 and / or at least partially one fastening opening 14. Such a setup can be seen e.g. in Figure 1 or Figure 6 in a perspective view or in Figure 3 or Figure 9 in a sectionized view. Such a setup of the fiber strands is, however, possible for all of the shown embodiments. As shown, the fiber strands 21 can be arranged along an inner side 24 of the layered walling, facing the inner space 8. The fiber strands 21 extend tangentially from the central opening 18 towards the respective fastening openings 14. Hence, the fiber strands 21 frame the star-like geometry of the mounting structure 7. However, also other placements, e.g. in the stiffening ribs are possible. The shown fiber strands 21 may by stitched together to form a stitched fiber structure 19, as explained above.

[0054] Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the scope of the invention.

[0055] DESIGNATIONS

[0056] Motorcycle wheel 16 Collar

[0057] Rotational axis 17 Central insert

[0058] Wheel center 18 Central opening

[0059] Circumferential rim 19 Stitched fiber structure

[0060] Hub 20 Stiffening ribs

[0061] Spoke 21 Fiber strands

[0062] Mounting structure 22 Outer thread

[0063] Inner space 23 Inner Thread

[0064] Outer wall 24 Inner side

[0065] End face 25 Cover

[0066] Star tips 26 Dome

[0067] Screw holes 27 Central plane

[0068] Fastening inserts 28 Outer flange part

[0069] Fastening opening 29 Connection element Bushing

Claims

PATENT CLAIMS1. Motorcycle wheel (1 ) with a wheel center (3) made of fiber-reinforced material and a circumferential rim (4), a. the wheel center (3) comprising a hub (5) and a plurality of spokes (6) extending from the hub (5) to the circumferential rim (4), and a shell-like mounting structure (7) for mounting of a break disc to the wheel center (3), the mounting structure (7) comprising an outer wall (9) encompassing at least partially an inner space (8) and having a star-like cross-section when viewed in the direction of a rotation axis (2) of the motorcycle wheel (1 ) with at least three star tips (11 ) extending in outward direction, wherein b. screw holes (12) are arranged in the region of the star tips (11 ) to each receive a fastening bolt.

2. Motorcycle wheel (1 ) according to claim 1 , wherein the shell-like mounting structure (7) has a star shaped end face (10) when seen in the direction of the rotation axis (2) of the wheel.

3. Motorcycle wheel (1 ) according to claim 2, wherein fastening inserts (13) for fastening the break disc are arranged within the end face (10).

4. Motorcycle wheel (1 ) according to claim 3, wherein the fastening inserts (13) each comprise a bushing (15) circumventing the respective screw holes5. Motorcycle wheel (1 ) according to claim 4, wherein the fastening inserts (13) and in particular the respective bushings (15) of the fastening inserts (13) extend into the inner space (8).

6. Motorcycle wheel (1 ) according to claim 4 or 5, wherein an outer side of the respective bushing (15) is at least partly conical.

7. Motorcycle wheel (1 ) according to any one of the claims 3 to 6, wherein the fastening inserts (13) extend through the wheel center (3) in direction of the axis of rotation (2).

8. Motorcycle wheel (1 ) according to any of the claims 3 to 7, wherein the fastening inserts (13) are connected to each other through a cover (25) attached to at least parts of the end face (10).

9. Motorcycle wheel (1 ) according to claim 8, wherein the fastening inserts (13) and / or the cover (25) are made from a solitary material.

10. Motorcycle wheel (1 ) according to any one of the preceding claims, wherein the star tips (11 ) of the mounting structure (7) are aligned with the spokes (6) of the wheel center (3).

11. Motorcycle wheel (1 ) according to any one of the preceding claims, wherein a central opening (18) of the wheel center (3) is arranged in the mounting structure (7) accommodating at least partially a central insert (17) extending into the inner space (8).

12. Motorcycle wheel (1 ) according to claim 11 , wherein the inner space (8) is designed such that it can be manufactured by applying layers of fiber plies on a core made from a resolvable material which can be removed through the central opening (18) after curing of a matrix material encompassing the fiber plies.

13. Motorcycle wheel (1 ) according to claim 11 or 12, wherein an outer contour of the star tips (11 ), when seen in the direction of the rotation axis, extends essentially tangential from the central opening (18).

14. Motorcycle wheel (1 ) according to any of the claims 11 to 13, wherein the motorcycle wheel (1 ) comprises two central inserts (17) arranged at least partially within the central opening (18) and opposite each other with respect to the hub (5).

15. Motorcycle wheel (1 ) according to claim 14, wherein the two central inserts (17) are connected directly with each other or indirectly via a connection element (29) extending through the wheel (1 ) and in particular through the inner space (8).

16. Motorcycle wheel (1 ) according to any one of the preceding claims, wherein the inner space (8) further extends at least partially into the spokes (6) and / or the hub (5).

17. Motorcycle wheel (1 ) according to any one of the preceding claims, wherein a cross section of the inner space (8) of the mounting structure (7) increasesin the direction of the rotation axis (2) and towards a central plane (27) of the wheel center (3).

18. Motorcycle wheel (1 ) according to any one of the preceding claims, wherein the fiber-reinforced material comprises fiber strands (21 ), in particular uni- directional fiber strands, circumventing at least partially an / the central opening (18) and / or at least partially one fastening opening (14).

19. Motorcycle wheel (1 ) according to claim 18, wherein the fiber strands (21 ) of the fiber-reinforced material are arranged in a stitched fiber structure (19).

20. Motorcycle wheel (1 ) according to any one of the preceding claims, wherein the motorcycle wheel (1 ) comprises two mounting structures (7) arranged opposite each other with respect to the hub (5) and each extending in direction of the rotational axis (2) outwards from the hub (5) and / or the spokes (6).

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