RIM, AND METHOD OF MANUFACTURING A RIM

Abstract

A method of manufacturing a fibrous composite bicycle rim , employs a tool device having a plurality of tool components including two molding devices and one circular device. The two molding devices each have one rim flank contact surface. The circular device includes a rim well contact surface. Tool components are provided, and a first varnish coat is applied to a rim contact surface and is dried. A first fiber layer of the fibrous composite material is applied to the flank contact surface of the molding devices, forming the outer fiber layers of the pertaining rim flanks. At least one first fiber layer of the fibrous composite material is applied to the circular device which forms the rim well. The tool components of are interconnected, and the tool device is closed, is heated up, and the smooth varnish coat firmly bonds with the hardening fibrous composite material.

Claims

1. A method of manufacturing a rim from a fibrous composite material for bicycle wheels equipped with a disk brake, employing a tool device, wherein the tool device comprises: a plurality of tool components, wherein the tool components comprise two molding devices and one circular device, wherein the molding devices each comprise a flank contact surface for forming a lateral rim flank, and the circular device comprises a rim well contact surface, with the following steps: at least part of the tool components is provided, and a first smooth varnish coat is applied to at least one rim contact surface on the tool components; the first smooth varnish coat is dried; a first fiber layer of the fibrous composite material is applied to the flank contact surface of the molding devices, forming the outer fiber layers of at least the greater part of the visible surface of the rim flanks; at least one first fiber layer of the fibrous composite material is applied to the circular device, which forms the rim well; the tool components of the tool device are interconnected, and the tool device is closed/locked; the tool device is heated up, and the varnish coat firmly bonds with the hardening fibrous composite material; and the tool device is cooled down, and the rim is removed, and spoke holes are made.

2. The method according to claim 1, wherein the molding devices with the flank contact surfaces are provided, and a first smooth varnish coat is applied to the flank contact surfaces of the molding devices, forming on the finished rim the outermost surface of at least a major part of the rim flanks, and wherein the circular device is also first provided with at least one smooth varnish coat.

3. The method according to claim 1, wherein at least two or three smooth varnish coats are applied successively, and wherein following application, the varnish coat is first dried respectively hardened.

4. The method according to claim 1, wherein the varnish coats are applied at a temperature of the tool components between 10° C. and 80° C.

5. The method according to claim 1, wherein the total thickness of the resulting smooth varnish coat is thinner than 0.7 mm, and wherein the dry weight of the resulting varnish coat is less than 7 grams, and wherein the weight ratio of the dry weight of the resulting varnish coat to the total weight of the rim is less than 1.5%.

6. The method according to claim 1, wherein at least one varnish is used which is taken from a group of varnishes including 1-pack and 2-pack varnishes, varnish coats based on isophthalic acid and/or neopentyl glycol, polyurethane coating, and varnishes based on acrylic resin.

7. The method according to claim 1, wherein at least one pattern is applied or incorporated by means of at least two spray nozzles, and wherein a type code or a color pattern is incorporated.

8. The method according to claim 1, wherein the tool device for hardening the fibrous composite material and for bonding with the varnish coat is temperature-controlled to a temperature between 100° C. and 150° C.

9. The method according to claim 1, wherein the following steps are carried out additionally: after applying the varnish coat, one molding device of the two molding devices is selected and provided, and the first fiber layer of the fibrous composite material is applied to the flank contact surface of the selected molding device, which, constituting a visible layer, forms at least a major part of the visible surface of the pertaining rim flank; the other of the molding devices is provided, and (at least) one first fiber layer of the fibrous composite material is applied to the flank contact surface of the other of the molding devices, which, constituting a visible layer, forms at least a major part of the visible surface of the other of the rim flanks; at least one first fiber layer of the fibrous composite material is applied to the circular device, which comprises a circumferential rim well contact surface, forming the rim well; and the circular device is placed against one of the molding devices, and the other of the molding devices is placed against it, and the circular device and the molding devices are connected with one another.

10. The method according to claim 9, wherein all of the fiber layer, which in use as intended form the visible outer surfaces as visible layers, are pressed on the molding devices and the circular device of the tool device, to ensure full-surface contact between the fiber layers and the flank contact surfaces, and to prevent flaws on the visible surface.

11. The method according to claim 9, wherein an auxiliary molding part of the tool device matching the selected molding device is connected with the selected molding device, so that the selected molding device together with the auxiliary molding part forms a mold surface for the rim base circling an axis of symmetry of the rim, which is configured in sections on the selected molding device, and in sections, on the auxiliary molding part, and wherein the first fiber layer is not only applied to the flank contact surface of the selected molding device, but also to the rim base region of the auxiliary molding part, to form a continuous first fiber layer in the region of the rim base, and wherein the auxiliary molding part is thereafter removed from the selected molding device, and wherein the two molding devices covered with fiber layers are interconnected, and wherein the first fiber layer applied to the selected molding device, forms the visible layer with the visible surface of the pertaining rim flank in the region of the flank contact surface, and in the rim base region of the auxiliary molding part, forms a reinforcement layer of the rim base but does not form the visible layer with the visible surface of the other of the rim flanks.

12. The method according to claim 11, wherein the two molding devices and the auxiliary molding part each have a mold parting surface running perpendicular to the axis of symmetry of the rim, where they are selectively placed against one another.

13. The method according to claim 1, wherein rim flanges are configured on the two rim flanks, and wherein one rim flange is formed by fiber layers, which are applied to one of the molding devices and to the circular device, and wherein one fiber layer on at least one rim flange is folded over at the radially outwardly edge and is radially folded back inwardly.

14. The method according to claim 1, wherein all the visible surfaces on the finished rim are formed by the two molding devices and the circular device.

15. The method according to claim 1, wherein the tool device loaded with the fiber layers is evacuated, and wherein the tool device is inserted into a pressure device and heated.

16. A rim for at least partially muscle-powered vehicles and in particular bicycles with opposite rim flanks, a rim well and a rim base, where the rim flanks meet in the radially most inwardly point, manufactured from at least one fibrous composite material by way of a method according to any of the preceding claims, and wherein the outer surface that is visible in operation as intended, is at least predominantly formed of a smooth varnish coat, which was inserted into the manufacturing mold prior to inserting the at least one fibrous composite material, and wherein the outer surface visible in operation as intended, does not, at least predominantly, comprise a varnish coat applied after removal from the manufacturing mold.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0091] The figures show in:

[0092] FIG. 1 a schematic illustration of a mountain bike with rims according to the application;

[0093] FIG. 2 a schematic illustration of a racing bicycle with rims according to the application;

[0094] FIG. 3 a schematic total view of a tool device according to the application for manufacturing a rim according to the application;

[0095] FIG. 4 an exploded view of the different components of the tool device according to FIG. 3;

[0096] FIG. 5 a molding device and an auxiliary molding part of the tool device according to FIG. 4;

[0097] FIG. 6 two sectional views of the tool device while manufacturing a rim;

[0098] FIG. 7 a schematic cross-sectional view of a finished rim according to the application;

[0099] FIG. 8 two sectional views of the tool device; and

[0100] FIG. 9 different sectional views while manufacturing the rims according to the application.

DETAILED DESCRIPTION

[0101] The FIGS. 1 and 2 each show a mountain bike respectively racing bicycle 100, each equipped with rims 1 according to the application. The mountain bike respectively racing bicycle 100 is provided with a front wheel 101 and a rear wheel 102, where rims 1 according to the application are employed. The two wheels 101, 102 are provided with spokes 109 connecting the rim 1 with the hubs 110. To this end, the rim 1 is provided with spoke holes 16.

[0102] A bicycle 100 comprises a frame 103, a handlebar 106, a saddle 107, a fork or suspension fork 104 and in the case of the mountain bike, a rear wheel damper 105 may be provided. A pedal crank 112 with pedals serves for driving. Optionally, an electric auxiliary drive may be provided on the pedal crank 112 and/or the wheels. The hubs 110 of the wheels may be attached to the frame by means of a clamping system 49 (for example a through axle or a quick release).

[0103] FIG. 3 shows the tool device 50 in the assembled state with the fiber layers already inserted to manufacture the rim 1, prior to inserting the tool device 50 into a separate pressure device, in which the tool device 50 is also heated to accelerate the hardening of the fibrous composite material. The tool device 50 is substantially configured rotationally symmetrical around an axis of symmetry 11, which at any rate forms an axis of symmetry for the finished rim 1.

[0104] FIG. 4 shows an exploded view of the tool device 50, at the top of which a locking ring 90 is illustrated that is provided with a clamping portion 91 and a screw, not visible. The locking ring 90 may be placed around the further components of the tool device 50, and may serve as a clamping ring. Optionally, this locking ring 90 may be omitted.

[0105] The bottommost component illustrated is a molding device 51, including a flank contact surface 52 which serves to form one of the two rim flanks of the rim 1 manufactured. The molding device 51 shows fasteners 56 and configured or disposed thereat, alignment units 57, to which the molding device 51 with the circular device 80 and the other of the molding devices 61 is fastened by means of appropriate fasteners 56, or to the alignment units 57. The circular device includes alignment units 87, and the other of the molding devices 61 includes alignment units 67.

[0106] As can be seen in FIG. 4, the circular device 80 or ring device 80 consists of a number of annular segments 81-83 extending in the peripheral direction around the central axis of symmetry 11. This allows separate removal of the annular segments.

[0107] FIG. 5 shows a molding device 51 and the pertaining auxiliary molding part 70, which are interconnected to cover the flank contact surface 72 and the rim base regions 54 and 74 with fiber layers of the fibrous composite material. In this way, the region of the rim base is reinforced by one joint, continuous layer.

[0108] The molding device 61 and the auxiliary molding part 70 are interconnected with, respectively placed on top of, one another on the mold parting surfaces 55 and 75.

[0109] FIG. 6 shows two schematic illustrations of the tool device 50 and fiber layers 21-23 and 25 disposed therein. The tool device comprises tool components 50a, 50b and 50c and in the assembled state substantially consists of a first molding device 51, a second molding device 61, and the circular device 80, which in turn consists (in the peripheral direction) of a number of annular segments 81-83 (see FIG. 4) and (in the axial direction) annular segments 85, 86.

[0110] Optionally, the molding devices 51 and 61 may be configured multipart and may for example additionally comprise molding parts 51a and 61a. Preferably, however, each of the molding devices 51 and 61 is configured as one piece. The molding device 51 has a flank contact surface 52 for the rim flank 2 on the left, while the rim flank 3 on the right is formed by a (side wall) flank contact surface 62. The flank contact surfaces 52 respectively 62 are covered with fiber layers 21 respectively 22. Reinforcement layers 25 are also applied in the region of the rim base 4. The rim well 5 is formed by at least one fiber layer 23, which is applied radially inwardly on the circular device 80.

[0111] The two rims 1 illustrated in FIG. 6 are each provided with rim flanges 6, 7, which are configured by fiber layers 21, 23 and 25. The outer surfaces 8 and 9 of the two rim flanks 2, 3, which will later be visible from the outside, are each formed by the first fiber layer 21 placed on the flank contact surface 52 and by the first fiber layer 22 placed on the flank contact surface 62. The visual range of the rim well is formed by the first fiber layer 23 placed on the circular device 80.

[0112] Following manufacturing respectively hardening a first respectively the previous rim, the rim is removed from the tool device 50. Then, the tool device 50 shows e.g. a temperature of 25° C. or 30° C. and may be left open for several minutes to cool down (e.g. 10 to 30 minutes). After cleaning and preparing including application of a primer coat if any, a first varnish layer (coat) is sprayed on (nebulized), preferably at (approximately) room temperature. Following a short hardening period (e.g. 5 to 10 minutes), two further varnish layers (coats) are preferably applied. Optionally, the tool device 50 may be heated up to a temperature of 40° C. or 60° C. or 80° C. However, hardening is also feasible “in air” at room temperature. Hardening may take between 1 minute and 15 minutes, depending on the temperature. Optionally, a (gentle) airflow may be used for assistance.

[0113] Rims are preferably manufactured (in particular only) for use with disk brakes. In particular, only the outer surfaces visible in the subsequent regular operation as intended are varnished. The rim flanks are preferably varnished up to the outside tips of the flanges. Basically, the surface in the region of the rim well may be varnished as well. The surface of the shape may be (slightly) roughened e.g. by way of laser structuring. Anodizing the rim contact surfaces of the tool device may also effect a matte surface of the rim flanks (often desired).

[0114] The varnish layers or coats 52a, 62a are, in particular, applied prior to assembling the tool device 50 from the tool components 50a, 50b and 50c respectively the molding devices 51 and 61 and the circular device 80. For these, varnish coats 52a, 62a are sprayed onto the flank contact surfaces 52, 62 preferably separately, respectively application is done singly. The resulting varnish coats are thin enough so as to be invisible in the scale of the FIG. 6 (which is not true to scale), but they are virtually thin lines. The resulting layer thickness is as a rule less than 0.5 mm. Preferably, several varnish layers are applied and form a varnish coat.

[0115] While the rim 1 is hardening, the varnish coats are transferred from the mold and firmly bond with the fibrous composite material. Thus, the rim 1 is finally removed together with the adherent varnish coat.

[0116] The “visible surfaces” respectively tangible surfaces, which are outside in operation, are formed by the varnish coats which as a rule are at least partially transparent. Thus, all the visible surfaces respectively all the visible layers of the finished rim 1 are provided by the fiber layers 21-23, each of which is applied separately and full-surface on the molding devices 51 and 61, and the circular device 80. This achieves a particularly high surface quality, since air pockets or other flaws can be avoided better than in the prior art.

[0117] To allow to apply pressure from the inside during hardening, a tube 32 (shown schematically only) is as a rule inserted, which can be guided outwardly through what is intended as the valve opening, and on which pressure can be applied after closing the tool device 50, to press each of the fiber layers 21-25 from the inside against the inner walls of the tool device 50. This secures a reliable composite. The tube 32 may be configured elastically, expanding when inflated. It is likewise possible and preferred for the tube 32 to be of sufficient size or matching configuration and with insertion, to be placed full-surface on at least one flank contact surface, and radially from the inside, placed full-surface on the circular device.

[0118] The ring device 80 or circular device may comprise an annular device 80a forming a core 80a (of a less elastic material) and (at least) one ring cover 40a of an elastic material such as a rubber material or a silicon material, disposed in the region of the side walls and the rim flanges and of the rim well, and applying pressure on the rim walls being formed. This may enhance the quality.

[0119] Optionally it is possible, as can be seen on the right in FIG. 6, to insert peripheral rovings or fiber bundles in the intersection of the rim flank with the rim well, to reinforce those regions and configure them still more robust.

[0120] FIG. 7 shows a simplistic illustration of a finished rim 1, which is not illustrated to scale. The rim 1 includes a rim base 4, a rim well 5, and rim flanks 2, 3, on which rim flanges 6, 7 are configured. In the outside region of the rim flanks, the resulting varnish coats 52a, 62a, which were transferred from the manufacturing mold to the rim, are illustrated enlarged and hatched. The varnish coat 52a may consist of a number of varnish layers or varnish coats 33-35 subsequently transferred to the tool components 50a, 50b, which together result in the resulting varnish layer thickness 2a or total varnish coat thickness 2a (on the rim flank 2). Resulting layer thicknesses of the varnish coat between approximately 0.2 mm and 0.7 mm are typical. Most frequently, a resulting layer thickness of approximately 0.3 mm to 0.5 mm is preset. A hollow space or hollow section 10 can be seen in the interior. The rim 1 is manufactured by way of a method according to the application and a tool device according to the application, of at least one fibrous composite material.

[0121] FIG. 8 shows two simplistic illustrations of the tool device 50 with the tool components 50a, 50b and 50c during manufacture. A number of varnish coats or varnish layers 33, 34 and 35 have been subsequently applied to the flank contact surfaces 52 and 62 of the molding devices 51 and 61, all together resulting in a varnish coat 52a on the flank contact surface 52 of the molding device 51. The other of the molding devices 61 in the region of the flank contact surface 62 is likewise coated correspondingly. The circular device 80 or the ring cover 40a of the circular device 80 is optionally also provided with a varnish coat, which is transferred to the walls of the rim during hardening.

[0122] FIG. 9 shows a simplistic illustration of the fiber layers on a tool device 50, wherein the outlines and the positions of the fiber layers 21-23 and 25 are shown intentionally roughly to give an illustrative example of the outlines of each of the fiber layers. It can be seen that the fiber layer 21 was not only placed onto the flank contact surface 52 of the molding device 51, but also onto the rim base region 74 of the auxiliary molding part 70, to later form a reinforcement section 21a in the region of the rim well contact surface 62 of the other of the molding devices 61. Thus, an overlap of each of the fiber layers is enabled from one of the rim flanks to the other of the rim flanks in the region of the rim base.

[0123] Circumferential rovings 29 may be provided in the intersecting region 15 of the rim flanges 6, 7 with the rim well 5 respectively the rim flanks 2, 3 or side walls.

[0124] In the lower region of FIG. 9, one can see the mold parting surfaces (contact areas) 55 and 65 and 75 of the two molding devices 51 and 61 and of the auxiliary molding part 70, where the two molding devices 51 and 61 respectively the auxiliary molding part 70 are joined.

[0125] FIG. 9 illustrates the state after connecting the selected molding device 51 with the auxiliary molding part 70, and placing fiber layers 21 and reinforcement layers 25 thereon. Thereafter, the auxiliary molding part 70 may be removed, and the circular device 80 may be placed against the selected molding device 51.

[0126] Then, a layer structure results which can already be seen in FIG. 6. After removal of the auxiliary molding part 70, the fiber layers 21-23 and 25 of the protruding reinforcement section 21a, and the correspondingly protruding regions of the fiber layers 25 (substantially) retain their shape due to the inherent stiffness of the prepregs 30 used. Thereafter, the other of the molding devices 61 can be placed onto the (selected) molding device 51 and the circular device 80, so that on the whole, a closed rim profile results for the rim 1. Then, in the region of the rim flange 7, the fiber layer 22 placed on the molding device 61 is pressed against the fiber layer 23 on the circular device 80. In the region of the rim base, the fiber layer 22 is pressed against the reinforcement section 21. Then, the tube 32 inflated in the further process in the interior of the hollow space 10 of the rim 1, reliably presses all the layers against one another and outwardly against the molding devices 51 and 62 and the circular device 80.

[0127] The outer surfaces of the finished rim, which are particularly significant for the visual effect, are configured in a high quality, since what are the outside fiber layers 21, 22 and 23 forming the visible layers of the finished rim 1, are each separately pressed full-surface against the corresponding contact surfaces (flank contact surfaces 52, 62 and rim well contact surface 84). The outer varnish coat once again clearly enhances the quality.

[0128] FIG. 9 shows the state after placement of a first fiber layer 21 onto the rim contact surface 52 of the selected molding device 51 and the rim base region 74 of the auxiliary molding part 70. Furthermore, reinforcement layers 25 have been placed, contacting the mold surface 14 for forming of the rim base 4 and assuming the corresponding shape. In the FIG. 9 on the left, the mold parting surfaces (contact surfaces) 55 and 75 of the molding device 51 and of the auxiliary molding part 70 are still in contact with one another.

[0129] In the radially outside region it can be seen that in the region of the rim flange 6, the fiber layer 21 has been folded over, forming a folded-over and radially inwardly extending section 21b for reinforcing the rim flange 6.

[0130] Accordingly, the other of the molding devices 61 is also loaded with fiber layers 22, wherein the fiber layer 22 only extends over the flank contact surface 62. In this spot, a section 22b is likewise folded over in the region of the rim flange 7.

[0131] A wall thickness 43 respectively thickness of a ring cover 40a is drawn in in FIG. 9, approximately corresponding to the wall thickness 6a, 6b in the region of the rim flank 2, 3 or of the rim flange 6, 7 (cf. FIG. 7). The wall thickness 43 may be only half of what is shown, or it may measure 2 mm, 3 mm, 4 mm, or 5 mm or 6 mm.

[0132] The wall thickness 43 lies, in particular, in the range between ⅒ and 10 times the minimum wall thickness 5a of the rim base 5 and/or it may preferably lie between 0.1 mm and 10 mm. In particularly preferred configurations, the thickness 43 lies between 1 mm and 6 mm and particularly preferably e.g. around 4 mm +/- 2 mm.

[0133] Thereafter, the auxiliary molding part 70 is carefully removed, and the other of the molding devices 61 is approached with the mold parting surface 65 to the mold parting surface 55 of the (selected) molding device 51, where they are attached to one another. Preferably, however, this is done after the ring device 80 or circular device 80 (in FIG. 9 illustrated above) has been placed onto the selected molding device 51.

[0134] In all the configurations, the various fiber layers may be placed on top of one another at various angles relative to one another. Thus, in one layer the fibers (warp fibers or weft fibers of a woven material) may be aligned at 30°, 60° or 45° to the peripheral direction of the finished rim. In a layer disposed on top thereof, the corresponding fibers may be aligned at another angle (e.g. another of the angles listed).

[0135] While hardening, the varnish coats 52a and 62a bond with the rim walls, and they can in turn be readily detached in removal from the (metallic) walls 52, 62 of the molding devices.

[0136] On the whole, the invention provides an advantageous method and an advantageous tool device, with which to manufacture rims 1 showing a reproducible, high quality. It is possible to provide a high surface quality of the outwardly visible surfaces, without complex refinishing work. A later, additional application of a varnish coat or the like is not required. This is made possible for example by the fact that the outwardly visible layers of all of the outside surfaces can be pressed immediately and directly on the corresponding varnish coats on the mold surfaces of the tool device.

[0137] The manufacturing method is simple and thus avoids defects, and reduces the reject rate.

[0138] The invention allows manufacturing of high quality rims directly out of the mold, achieving good scratch resistance and weathering resistance. Minor flaws are considerably reduced. This is why subsequent repairs can be dispensed with as a rule. The method according to the application dispenses with the time-consuming and cost-intensive subsequent varnish coating of the components. The visual appearance, haptics, and the mechanical properties, as well as the UV resistance, scratch resistance or chemical resistance can be improved. The film thickness applied can be thin (and thinner), which is ideal for lightweight construction. The surface can be manufactured absent any pinholes. A complex, subsequent surface pretreatment with fillers and primers following the removal of the rim from the manufacturing mold can be dispensed with. Cost reduction ensues from time saved since subsequent and separate later coating is omitted. The adhesion between the component and “varnish” is excellent, and results in high mechanical resistance, high climatic resistance, and a high degree of UV protection for the rim. A saleable surface “out of the mold” can be achieved, requiring virtually no finishing work (grinding/putty/varnish). The result shows a high degree of efficiency and a lower weight due to reduced film thicknesses. The adhesion of the varnish to the rim can be improved. This also results in reduced susceptibility to scratches in the surface and an improved decal adhesion. Moreover, the reproducibility can be improved. The resulting ecobalance is improved as well.

[0139] While a particular embodiment of the present rim, and method of manufacturing a rim have been described herein, it will be appreciated by those skilled in the art that changes and modifications may be made thereto without departing from the invention in its broader aspects and as set forth in the following claims.

List of Reference Numerals

[0140] TABLE-US-00001 1 rim 51a molding unit 2, 3 rim flank, rim side wall 52 flank contact surface 2a varnish coat thickness 52a varnish coat 4 rim base 54 rim base region 5 rim well 55 mold parting surface 5a minimum wall thickness 56 fastener 6, 7 rim flange 57 alignment unit 8, 9 visible surface 61 molding device 10 hollow space 61a molding unit 11 axis of symmetry 62 flank contact surface 14 mold surface for forming the rim base 62a varnish coat 64 rim base region 15 intersecting region 65 mold parting surface 16 spoke hole 67 alignment unit 20 fibrous composite material 70 auxiliary molding part 74 rim base region 21 fiber layer, visible layer 75 mold parting surface 77 alignment unit 21a reinforcement section 80 circular device, ring device 21b folded-over section 22 fiber layer, visible layer 80a annular unit, core 80b material of 80a 22b folded-over section 81-83 annular segments 23 fiber layer, visible layer 84 rim well contact surface 85, 86 annular segments 24 fiber layer 87 alignment unit 25 reinforcement layer 90 locking ring 29 roving 91 clamping portion 30 prepreg 100 bicycle 32 tube 101 wheel, front wheel 33-35 varnish layer 102 wheel, rear wheel 36 resulting varnish coat 103 frame 40 cover 104 fork, suspension fork 40a ring cover 105 rear wheel damper 40b material of 40a 106 handlebar 41 pressing ring 107 saddle 42 pressing ring 109 spoke 43 thickness 110 hub 50 tool device 112 pedal crank 50a-c tool component 51 molding device