METHOD FOR MANUFACTURING A BICYCLE RIM AND BICYCLE RIM

Abstract

A method for making a bicycle rim, having a rim body with at least one integrated cavity . The cavity is enclosed by a component wall. The rim body extends in a rim plane over 360 transverse to its rotational axis.

The cavity forms a chamber in the rim body. A plurality of component walls have two lateral rim flanks, a radial inner rim base and a radial outer rim well, which limit the chamber. A rim body support structure is formed by a fibre structure. A fibre bundle is attached to a carrier layer and passed reciprocally on the carrier layer to form a basic fibre layer of the fibre structure. The fibre structure is draped in a tool mould. A filling unit is placed in the tool mould so that the filling unit keeps the volume free for the cavity and the cavity is surrounded by the component wall.

Claims

1. A method for producing a bicycle rim comprising a rim body with at least one cavity integrated within it, wherein the rim body extends in a rim plane over a circumference of 360 transverse to its rotational axis, and wherein the cavity forms a hollow chamber in the rim body,; the method comprising: wherein a plurality of component walls are formed, wherein the component walls comprise two lateral rim flanks, a radial inner rim base and a radial outer rim well, which delimit the hollow chamber;; wherein a support structure of the rim body is formed by at least one fibre structure; wherein for the production of the fibre structure a fibre bundle is attached to a carrier layer with thread elements and is passed back and forth on the carrier layer to form a basic fibre layer of the fibre structure; and wherein at least one fibre structure is draped in a tool mould, and wherein one filling unit is placed in the tool mould so that the filling unit keeps the volume free for the cavity and is surrounded by the component wall.

2. The method according to claim 1, wherein at least one fibre structure extends over a considerable proportion of the circumference transversely to the rotational axis of the rim body and over at least one quarter.

3. The method according to claim 1, wherein a fibre structure forms a substantial part of at least one rim flank, and a further fibre structure forms the rim well.

4. The method according to claim 3, wherein a different fibre structure forms a substantial part of the other rim flank.

5. A method according to claim 1, wherein rim flanges are formed radially outwards, wherein a rim flange is formed by the fibre structure forming the rim flank and the further fibre structure, wherein the fibre structure forming the rim flank at the radial outer end radially covers or surrounds the further fibre structure radially outwards.

6. The method according to claim 1, wherein the fibre structures forming the rim flanks each have the same outer diameter and different inner diameters and wherein the fibre structures forming the rim flanks are each formed in a circular ring.

7. The method according to claim 1, wherein a fibre structure is applied to the rim base.

8. The method according to claim 1, wherein in the case of at least one fibre structure with the fibre bundle is deposited and fastened at least in sections on the basic fibre layer at least one further fibre layer in order to apply and fasten a flat further fibre layer on the base fibre layer, so that the fibre structure is more strongly developed at defined sections than in other areas.

9. The method according to claim 1, wherein the fibre bundle is sewn or embroidered with a thread element on the carrier layer or a fibre layer of the fibre structure and wherein at least one filament element consists of a thermoplastic material and wherein the fibre bundle comprises at least two fibres and wherein the fibre bundle comprises reinforcing fibres.

10. The method according to claim 1, wherein the fibre bundle comprises fibres of matrix material and wherein the fibres are melted from the matrix material to form together with the reinforcing fibres at least a part of the component body.

11. The method according to claim 1, wherein the carrier layer is removed after the fibre structure has been produced.

12. The method according to claim 1, wherein the fibre structures are pre-formed in three dimensions and secured in their three-dimensional shape with a fibre binder and then inserted into the tool mould.

13. The method according to claim 1, wherein the tool parts of the tool mould are closed, and matrix material is injected.

14. The method according to claim 1, wherein the thread element is retained in the component body or wherein the thread element is at least partially melted during the completion of the component body.

15. A bicycle rim with a rim body at least one integrated cavity; wherein the rim body extends in a rim plane over a circumference of 360 transverse to its rotational axis,; wherein the cavity forms a hollow chamber in the rim body;; wherein a plurality of component walls are comprised, wherein the component walls comprise two lateral rim flanks, a radial inner rim base and a radial outer rim well, which limit the hollow chamber, wherein the cavity is enclosed all around by at least one surrounding component wall;; wherein a support structure of the component body is formed by at least one fibre structure; and wherein the fibre structure comprises a fibre bundle which is guided back and forth within the fibre structure and fastened (to each other) with thread elements, wherein the rim body consists at least partially of a fibre composite, wherein the fibres of the fibre composite are embroidered onto a carrier layer.

Description

[0062] The figures show:

[0063] FIG. 1 a schematic illustration of a mountain bike with bicycle rims according to the invention;

[0064] FIG. 2 a schematic illustration of a racing bike with bicycle rims according to the invention;

[0065] FIGS. 3a-3d schematic sections through a tool mould in the production of bicycle rims;

[0066] FIGS. 4a-5d schematic perspective illustrations of fibre structures in the production of bicycle rims;

[0067] FIG. 5 a machine for the production of a fibre structure for the bicycle rims according to the invention; and

[0068] FIGS. 6a-6d fibre structures produced by the machine in accordance with FIG. 5.

[0069] FIGS. 1 and 2 depict bicycles 200, each of which has two bicycle rims 50 according to the invention. The mountain bike or road bike or gravel wheel 200 each has handlebars 60, a front wheel 101 and a rear wheel 102, each of which has bicycle rims 50 according to the invention. On the rear wheel 102 there is a sprocket device 111. The two wheels 101, 102 each have spokes 109. Conventional rim brakes or other brakes such as disc brakes can also be provided.

[0070] A bicycle 200 has a frame 103 that includes frame components 70. The bicycle 200 has a saddle 107, a fork or suspension fork 104 and, in the case of the mountain bike, a rear-wheel shock absorber 105 can be provided. A pedal crank 112 with pedals serves as the drive. If necessary, an electric auxiliary drive may be provided on the pedal crank 112 and/or the wheels where applicable.

[0071] In FIGS. 3a to 3d, various bicycle rims 50 can be seen as bicycle components 100 when manufactured in a tool mould 40. The bicycle rims 50 each have a single-piece rim body 1.

[0072] FIG. 3a shows a simple and very favourable design, in which two tool mould halves 41 and 42 are used for the tool shape 40, which are used to shape the rim flanks 54, 55, the rim base 56 and the rim flanges 58. Tool parts 43 can be used to shape the rim well 57.

[0073] FIG. 3a shows a cover 44 made of a more elastic material, which rests against the rim flanges 58 and the rim well 57. The cover 44, for example, is made of silicone and is inserted into the tool. The cover 44 allows for better production of the rim flanges 58. During production, it is important that the outer fibre structures 11, 12 cover or even surround the fibre structure 13 at the radial outer end of the rim flanges 58. In particular, the end 11a, 12a of the respective fiber structure 11, 12 is folded over and extends over or better or or an even larger proportion of a radial height of the rim flange radially back inwards. This protects the radial outer end of the fibre structure 13. In addition, the free ends 11a, 12a are also protected and are not directly exposed to impacts on the rim flange. This results in significantly better protection of the rim even in the event of strong impacts or high loads.

[0074] The fatigue strength is positively influenced if the fibre structures 11 and 12 surround the fibre structure 13 at the radial outer end (in the horn) and is extended around the fibre layer 13. The failure behaviour (damage pattern in the case of impact) is also positively influenced in this way. The bicycle rim is safer. This applies to all types of rims. To ensure that the rim flanges are optimally manufactured and compressed, the use of a more elastic cover in the form of a silicone ring, for example, is very favourable.

[0075] FIG. 3a (above) shows a variant in which the ends 11a, 12a extend back almost over the entire height of the rim flange. FIG. 3a (below) shows a variant in which the fiber structures 11, 12 extend radially inwards again over only part of the height. In both variants, the ends of the fibre structures are taken up in a protected manner.

[0076] Preferably, the fibre structures 11, 12 form the visible layers of the rim flanks.

[0077] FIG. 3a shows an enlarged variant above, which has two separate ring covers 44a, 44b, especially in the form of silicone rings, in order to optimally design and compress the rim flanges 58.

[0078] However, it is also possible that the use of silicone rings or other covers 44 or such inserts as is shown in FIGS. 3c and 3d, where a cover 44 is not drawn, is dispensed with. Preferably, one cover 44 (or two 44a, 44b) is used. Accordingly, then also in FIGS. 3c and 3d.

[0079] In a particularly simple and favourable embodiment, as shown in FIG. 3b, only three individual separate fibre structures 11, 12 and 13 are used to produce the bicycle rim 50. The fibre structures 11, 12 and 14 are produced in an adapted manner according to the method in accordance with FIGS. 6a, 6b, 6c and 6d. The finished fibre structures 11, 12 and 13 are placed in the tool mould 40 before it is sealed. Here, the fibre structure 11 forms the right rim flank 55, while the fibre structure 12 forms the left rim flank 54. In principle, a reverse embodiment is also possible, in which the fibre structure 12 forms the right rim flank 55 and the fibre structure 11 forms the left rim flank 54.

[0080] The fibre structures 11 and 12 are each formed in a circular ring, and each have the same outer diameter 11b. This outer diameter 11b is determined by the diameter of the rim flanges 58. The inner diameter 11a, 12a of the two fibre structures 11, 12 differs here, since the fibre structure 12 extends radially inwards not only to the central rim level 52, but also forms an overlap beyond it, and the other rim flank and fibre structure 11 overlap to reinforce the rim base 56.

[0081] FIG. 3c shows a cross-section, wherein it can be seen that the fibre structure 13 completely formed the rim well 57 and parts of the rim flanges 58.

[0082] The central rim level 52 is drawn. The same applies to the rotational axis 53, which forms a symmetry axis of the rim. The rim rotates around the rotational axis 53 in the intended normal operation. The rotational axis 53 is a symmetry axis of the rim, around which it extends in a rotationally symmetrical manner.

[0083] Inside the bicycle rim 50, a cavity 2 can be seen, which forms a hollow chamber 3 here. For example, when making the rim, a tube or core is placed inside the tool mould 40 as a filling unit 45 to fill the cavity 2 to be produced.

[0084] The cavity 2 is surrounded by the component walls 4, namely the rim flanks 54, 55, the rim base 56 and the rim well 57.

[0085] In the exemplary embodiment in accordance with FIG. 3a, three fibre structures 11, 12 and 13 were used for production. In the exemplary embodiment in accordance with FIG. 3c, a fourth fibre structure 14 is used, which serves to form and reinforce the rim base 56. In this case, it is not absolutely necessary for the fibre structures 11, 12 to extend radially inwards towards the rim base 56. In this exemplary embodiment as well, only very few fibre structures are used, since the fibre structures extend completely over the circumference around the rotational axis 53.

[0086] FIG. 3d shows another exemplary embodiment, wherein, for example, a fibre structure 11 is used here, which forms the rim flanks and the rim base. Furthermore, the fibre structure 11 also contributes to the stability of the rim well 57. A fibre structure 13 also contributes to the formation of the rim well 57. On the sides, two fibre structures 14 are drawn here to reinforce the rim flanges 58. A total of four fibre structures can be sufficient to produce the entire bicycle rim 50. Process reliability is significantly increased by the (very strongly) reduced number of fibre pieces to be (manually) inserted into the tool mould.

[0087] With reference to FIGS. 4a to 4d, vividly perspective representations of the fibre structures 11 to 14 used in the production of different bicycle rims 50 are shown as bicycle components 100. In FIG. 4a, only two different fibre structures 11 and 13 are used, wherein fibre structure 11 contributes to the formation of the rim flanks 54, 55 of the rim base 56. The fibre structure 13 contributes to the reinforcement of the rim flanges and the formation of the rim well 57. It can be seen that individual defined sections 24 serve as reinforcement sections, where an additional fibre layer has been applied to the base fibre layer or at least a lower fibre layer. Through the targeted application of the fibre bundle 15 or the fibre bundle 15 and the targeted three-dimensional structure of the fibre structures 11 to 14, a corresponding locally targeted reinforcement of the component body 1 can be carried out in each case.

[0088] Basically, a fibre bundle 15 extends completely through a respective fibre structure 11, 12, 13 or 14.

[0089] FIG. 4b shows a variant in which separate fibre structures 11, 12 are used for the two rim flanks. An additional fibre structure 13 is used to form the rim well 57.

[0090] FIG. 4c shows a variant in which two fibre structures 11 and 12 are provided for the formation of the rim flanks 54 and 55, while a fibre structure 13 is used to reinforce and form the rim well 57. In the lateral areas and also in the radial inner area, reinforcement sections 24 (defined sections) can be seen here, while there are also areas 25 that have a lower number of fibre layers than in reinforcement sections 24.

[0091] Finally, FIG. 4d shows a variant of a bicycle rim 50, in which the support structure 5 is formed by a fibre structure 11 and a fibre structure 13. The fibre structure 11 provides the two rim flanks 54 and 55 and the rim base 56, while the fibre structure 13 forms the rim well 57 and contributes to the stability of the rim flanges 58. Certain defined sections 24 have at least one additional fibre layer 22, while other areas 25 are not reinforced.

[0092] FIG. 5 shows a schematic view of a machine 90 for the prefabrication of fibre structures 11 to 14 (compare FIGS. 4a to 4d), wherein a fibre bundle 15 is unwound and fed from a roll. The machine 90 has a three-dimensionally movable machine head 91 (in x, y and z directions) and is controlled by an integrated and/or external control system 92. The fibre bundle 15 is specifically positioned and placed on a carrier layer 20 that is not visible in FIG. 3 (compare FIG. 4a) and attached there by means of a thread element 19.

[0093] In simple cases, the fibre bundle 15 can be attached to the carrier layer 20 by sewing and/or embroidery. A single thread element 19 can be used or an upper thread and a lower thread can be used as thread element 19.

[0094] FIGS. 6a to 6d show views of different fibre structures 11 to 14, which illustrate the principle.

[0095] In the case of the control system of machine 90, which is controlled in particular by computer technology, the head of the machine is positioned in such a way that fibre bundle 19 is positioned and moved in a targeted manner on the carrier layer 20.

[0096] The escaping fibre bundle 15 is attached to the carrier layer 20 with the thread element 19 or the thread elements 19, wherein the fibre bundle 15 is moved back and forth and in particular criss-cross over the carrier layer 20. In the process, the fibre bundle 15 is attached to the carrier layer 20. However, the fibre bundle 20 is also attached to itself at the intersecting points.

[0097] Overall, almost the entire (intended area of) carrier layer 20 is preferably covered with fibre bundle 15, resulting in a first fibre layer or base fibre layer 21, as FIG. 6b shows. A further fibre layer 22 is placed on top of it, wherein the individual fibres 16 (compare FIG. 4d) regularly extend in a single piece and completely through the base fibre layer 21 and the further fibre layer 22.

[0098] However, it is also possible that after the basic fibre layer 21 has been deposited, a separate or different fibre bundle 15 is used to deposit and attach another fibre layer 22 to the base fibre layer 21.

[0099] It is possible that the further fibre layer 22 with the thread elements 19 is attached directly and only on the first or basic fibre layer 21. However, it is also possible that the second fibre layer 22 is (also) attached to or to the carrier layer 20.

[0100] In all embodiments and embodiments, the carrier layer 20 is preferably thinner than a (minimal) diameter of a fibre bundle 15. In particular, a thickness of the carrier layer 20 is less than a quarter or even 1/10 of a (maximum) diameter of a fibre bundle 15. In all embodiments, a fibre bundle 15 can be circular, oval or square, square, rather flat or square with rounded corners, for example.

[0101] FIG. 6c shows a somewhat more complex fibre structure 11, in which two or also three fibre layers are deposited and attached to the substrate material or the carrier layer 20. Overall, the fibre structure 11 forms a support structure 5 for the bicycle component 100.

[0102] FIG. 6d shows a schematic cross-section through a support structure 5 or a fibre structure 11, 12, 13, 14, wherein the thin carrier layer 20 consisting of a fleece layer 20a and/or a film 20b with the base fibre layer 21 placed on it and the further fibre layer 22 positioned on it can be seen in the cross-section. Purely schematically, the fibre bundles 15 with the individual fibres 16 contained in them can be recognized. The individual fibres 16 can each be formed as reinforcing fibre 17 and/or as matrix fibre 18. Matrix fibres 18 are integrated especially when the bicycle component 101 uses thermoplastic matrix material. Then at least part of the required matrix material can be provided by fibre bundle 15.

[0103] FIG. 6d shows a strongly schematic cross-section of a finished product to show the principle. In this case, individual thermoplastic matrix fibres 18 and thermoplastic filament elements 19 may be dissolved and contained in the matrix material 6 and may no longer be easily or not at all visible to the naked eye in the section where applicable.

[0104] Overall, an favourable bicycle rim 50 is produced, which includes a one-piece rim body 1 with a hollow chamber 3, wherein only a small number (<15 and especially less than 9) fibre structures are used to reliably produce a lightweight and stable bicycle rim.

TABLE-US-00001 Reference list: 1 rim body 2 cavity 3 hollow chambers 4 component wall 5 support structure 6 matrix material 11 fibre structure, rim flank structure 11a inner diameter 11b outer diameter 12 fibre structure, rim flank structure 12a inner diameter 12b end 13 fibre structure, rim well structure 13a length 14 fibre structure, rim base structure 15 fibre bundle, fibre roving 16 individual fibres 17 reinforcement fibre 18 matrix fibre 19 thread elements, thread 20 carrier layer, carrier material, (underlay) 20a fleece layer 20b film 21 basic fibre layer 22 additional fibre layer 24 defined section, reinforcement section 25 region (not reinforced) 40 tool mould 41 tool part 42 tool part 43 tool part 44 cover 44a ring cover 45 filling unit, core, tube 50 bicycle rim 52 rim plane 53 rotational axes 54, 55 rim sidewall (11, 12) 56 rim base (e.g., 14) 57 rim well (13) 58 rim flanges 60 handlebars 70 frame components 90 machines 91 machine head 92 control system 100 bicycle components 101 wheel, front wheel 102 wheel, rear wheel 103 frame 104 fork, suspension fork 105 rear-wheel shock absorber 107 saddle 109 spoke 111 sprocket device 112 pedal crank 200 bicycle