Disc wheel

Abstract

Disc wheel (01) comprising a hub (02), an inner skeleton (03) surrounding the hub (02) with at least two spokes (04) and at least one cover (07), characterized in that the inner skeleton (03) is at least partially made of a fiber composite material.

Description

[0001] The invention relates to a disc wheel.

[0002] Disc wheels are well known in the art. Disc wheels have a closed surface on the flanks, which in conventional wheels is formed by the spokes. This surface serves to reduce air resistance and turbulence while driving. This generally reduces the power required under otherwise identical driving conditions, allowing for faster driving speeds.

[0003] Two designs in particular have become established. On the one hand, it is known to attach covers made of solid plastic to classic wheels with wire spokes as hubcaps. An example of this is known from EP 2 674 304 A1.

[0004] On the other hand, it is known to design the disc wheel as a single-piece disc with the rim made of fiber composite material, dispensing with spokes. The disc itself assumes the supporting function of the spokes. Such a wheel is known, for example, from EP 0 362 509 A1.

[0005] In general, disc wheels have the disadvantage compared to conventional road wheels in that they are significantly heavier due to their flat design. While disc wheels, in which the disc itself assumes the load-bearing function, are already lighter than the first design with a hub cap, the discs still need to be made more solid to assume the load-bearing function. Consequently, their weight remains comparatively high compared to conventional road wheels. Furthermore, repairs to such road wheels are impossible due to their flat, load-bearing design. Damage always weakens the integrity of the load-bearing part of the disc wheel, posing a permanent risk of breakage during use. A damaged disc wheel of this design should therefore always be replaced completely.Another problem with disc wheels with a load-bearing disc is their reduced elasticity, which reduces shock absorption. This increases the stress on the disc wheels and reduces ride comfort.

[0006] There is therefore a great need for a disc wheel that is as light and stable as possible, with particular emphasis on simple, quick, and effective repair options while maintaining maximum safety. Furthermore, the disc wheel should be cost-effective to manufacture. The invention therefore sets itself the task of providing a disc wheel that overcomes the aforementioned difficulties.

[0007] This problem is solved in a surprisingly simple but effective manner by a disc wheel according to the teaching of independent claim 1.

[0008] According to the invention, a disc wheel comprising a hub, an inner skeleton surrounding the hub with at least two spokes, and at least one facing is proposed. The disc wheel according to the invention is characterized in that the inner skeleton is made at least partially of a fiber composite material. Preferably, the inner skeleton is made entirely of a fiber composite material.

[0009] The basic idea of ​​the invention is to reduce the weight of the disc wheel by using an internal skeleton made of a fiber composite material. Skeletons or spoke systems made of a fiber composite material are lighter than the weight of the spokes on conventional wheels with wire spokes. The use of spokes achieves greater comfort and lower stress due to their better elasticity. However, with a fiber composite material, the well-known problem of weakening due to delamination occurs. During delamination, the outermost layers of the fiber composite material are partially separated, with the initial cause usually being damage caused by an external influence and / or impact. This damage continues until it weakens or even completely destroys the wheel. This disadvantage is remedied by the veneer, which performs a dual function.On the one hand, it reduces drag and turbulence, and on the other, it protects the inner skeleton from damage. The protection also allows the inner skeleton to be made thinner and lighter. Since the cladding performs little or no load-bearing function, it can be made thin and thus lightweight.

[0010] Repairing the veneer after damage is easy, as it doesn't perform a load-bearing function, so weakening it is irrelevant. In cases of excessive damage, the veneer can simply be replaced. The internal skeleton can still be used.

[0011] A disc wheel is characterized by its closed surface. This closed surface is created by a cover arranged as a cover. The cover is fixed, meaning it does not move relative to the wheel.

[0012] To ensure the disc wheel can roll properly during driving, it includes a hub located centrally within the disc wheel. The hub includes and / or encloses an axle that either rotates together with the hub and the disc wheel relative to the vehicle on which the disc wheel is mounted during driving. Alternatively, the axle is fixed relative to the vehicle, with the hub and the disc wheel rotating around the axle during intended use.

[0013] The inner skeleton, or rather the cladding, is arranged around the hub. The inner skeleton assumes the load-bearing function, meaning it transfers the weight of the rider and the usual parts of the vehicle, as well as any other load, at least partially to the ground via the hub, the rim, and the tire.

[0014] To distribute the weight, the inner skeleton comprises at least two spokes, with the spokes preferably being evenly distributed around the circumference. This means they always have the same angle to the adjacent spoke. The spokes extend radially outwards from the hub to a rim. The rim accommodates a tire that ultimately comes into contact with the ground. It is conceivable for the spokes to be twisted in or against the circumferential direction to enable a tangential component of engagement with the hub and / or the rim. The inclined position enables better torque transmission. In principle, the inner skeleton can be made of any fiber composite material. However, carbon fiber and / or carbon fiber reinforced plastic (CFRP) have proven particularly suitable. These fiber composite materials are particularly stable and at the same time particularly light.They are therefore highly suitable for the requirements of the inner skeleton. The inner skeleton is preferably manufactured using a lamination process, an additive manufacturing process, in particular a 3D printing process, and / or an injection molding process. The spokes are preferably tubular or rod-shaped. They can also be flat and have an oval cross-section.

[0015] As already explained above, the cover serves, on the one hand, to reduce air resistance and turbulence at the impeller, and, on the other hand, to protect the inner skeleton from impacts. For this purpose, the cover is designed as a thin, flat, or substantially conical disc. Preferably, the cover comprises a central recess through which a portion of the hub extends. More preferably, the cover comprises at least one further recess.

[0016] Basically, it is irrelevant what type of vehicle the disc wheel is used for, but it is particularly preferred for a bicycle, in particular a triathlon bike, a trike, a cargo bike, a trailer, in particular a trailer for a bicycle, a carriage or a wheelchair.

[0017] The term "disk wheel" refers to an impeller with at least one closed surface spanned in the radial and circumferential directions. Preferably, the disc wheel comprises two closed surfaces spanned in the radial and circumferential directions.

[0018] The term "internal skeleton" refers to a component that, when used as intended, is at least partially, preferably completely, shielded from the environment by another component or components, in particular one or more facings. The internal skeleton is further characterized by its design with struts known as spokes for dissipating forces.

[0019] The term “fiber composite material” refers to a composite material consisting of fibers known from the state of the art embedded in a matrix. The fibers are preferably in at least two, three, four, five, six, seven, eight, nine, ten, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100 or more layers arranged one above the other. They can essentially run parallel or in different directions, although in the latter case they are usually interwoven into fabrics.It has been recognized as essential that the at least two layers of the fiber composite material remain fully bonded and do not delaminate during intended use. The term "delamination" is defined by those skilled in the art as the partial or complete separation of the layers of the fiber composite material from one another.

[0020] The term "intended use of the disc wheel" refers to the use of the disc wheel equipped with a tire when installed on the vehicle. This includes, in particular, driving and / or standing the vehicle on any type of surface, in particular on flat, uneven, straight, uneven, paved, and / or unpaved surfaces. During intended use, the disc wheel may be exposed to external influences and / or impacts. Within the scope of the invention, it has been recognized that the internal skeleton of the disc wheel according to the invention is protected against external influences and / or impacts due to the structural design and the arrangement of the cover.

[0021] The term "impact" refers to an impact on the disc wheel during its intended use, particularly impacts caused by a jump, such as a sports jump, an obstacle, or rolling over uneven surfaces in the roadway, such as stones, rocks, roots, and / or other vegetation, or edges and / or bumps caused by road construction. This can occur, in particular, when driving on a flat, uneven, paved, unpaved, fully or partially developed and / or asphalted road or path, and / or off-road.

[0022] The term "external influence" refers to a force acting on the disc wheel due to intended use and / or improper use, for example, when not installed in the vehicle. This includes, but is not limited to, a fall, an accident, a collision, especially with one or more other vehicles, vandalism, an impact, improper maintenance, and / or improper repair.

[0023] By means of the invention, it is possible to provide a lightweight and stable disc wheel in a cost-effective manner, which offers a simple, quick and good possibility for repair while maintaining the highest level of safety.

[0024] Advantageous further developments of the invention, which can be implemented individually or in combination with one another, are presented in the subclaims.

[0025] It is conceivable that the inner skeleton comprises a rim. The rim is preferably formed integrally, in particular in one piece, even more preferably monolithically, with the inner skeleton. A disc wheel requires a rim to accommodate a tire. If the rim is designed integrally with the inner skeleton, a further weight reduction can be achieved, since, in particular, connecting means that connect the rim to the inner skeleton can be eliminated. Particularly preferably, the rim is made at least partially, more preferably entirely, from a fiber composite material. This also makes the rim lightweight and stable.

[0026] The term “integral” refers to the connection between the inner skeleton and the rim during the manufacture of the inner skeleton and / or the rim.

[0027] The term "one-piece" refers to the ability to be manufactured in a single production process as a structural unit, such as, in particular, but by no means exclusively, in a single manufacturing process for a fiber composite material. In particular, the subsequent attachment of additional separate components is not necessary. Subsequent corrective work, such as filing, is not considered a separate manufacturing process.

[0028] The term "monolithic" refers to a component that consists of a single piece of material, is designed to be continuous and seamless. In particular, a monolithic component is made of a homogeneous material, i.e., a single material, in this case, a single fiber composite material.

[0029] In a further development, it is conceivable for the internal skeleton to be designed as a single piece, particularly monolithic. A single piece, particularly monolithic, construction can further reduce weight and simplify production, as production takes place in just a few steps and the weight of the fasteners connecting the parts can be eliminated.

[0030] Furthermore, it is conceivable for the inner skeleton to enclose at least one hollow space. The fiber composite material can be designed as a hollow body, it being known to those skilled in the art that such hollow bodies have high stability with comparatively low weight. The cavity can extend into one or more of the spokes and / or around the hub. It can be designed as a continuous space, or several cavities can be arranged in the inner skeleton. In addition, a cavity can extend into the rim, described elsewhere, so that the rim is designed as a hollow chamber rim. The cavity in the rim can be connected to one or more cavities in the spoke. This brings about a further reduction in weight while otherwise maintaining the same stability of the inner skeleton according to the invention.

[0031] It is advantageous if the cladding is also made of a fiber composite material. As described elsewhere, fiber composite materials are both stable and lightweight. Since the cladding has little or no load-bearing function, damage to the fiber composite material is significantly less critical in the cladding than in the internal skeleton. Therefore, any damage to the cladding can also be easily repaired, as stability is not critical at this point. Preferably, the internal skeleton and cladding are made of the same fiber composite material. The use of fiber composite materials for the cladding leads to a further reduction in weight.

[0032] Furthermore, it is conceivable for the inner skeleton to comprise between three and ten spokes. More preferably, the spokes are evenly distributed around the circumference of the disc wheel. The inner skeleton most preferably comprises six spokes. If the inner skeleton comprises more spokes, they can be designed to be slimmer and more delicate. However, an increase in the number of spokes also means an increase in weight. The even distribution also allows for better concentricity of the disc wheel with more spokes, while at the same time providing pleasant shock absorption. For the basic functionality of the disc wheel, it has been shown that at least two spokes are necessary. A number of three to ten spokes has proven to be a good compromise between the concentricity of the disc wheel and the desired weight reduction, ride comfort, and reduced load.

[0033] In a further development, it is conceivable that the inner skeleton and the hub are connected by a material-to-metal connection. A material-to-metal connection guarantees a long-lasting, yet slip-free and surface-to-surface connection between the two components. The hub's job is to rotate around an axis that is fixed to the bicycle frame, or to rotate with the axis in relation to the vehicle. Since fiber composite materials have poor abrasion properties, the hub is often made of a different material, particularly metal. Therefore, a connection must be created between the inner skeleton and the hub. The surface-to-surface design of the material-to-metal connection allows forces to be transferred particularly well and efficiently from the disc wheel to the vehicle. Furthermore, if an adhesive is used for the material-to-metal connection, the adhesive can be used as a damping agent between the inner skeleton and the hub.Additionally or alternatively, it is conceivable to form the connection in a form-fitting manner using coordinated contours. The coordinated contours are particularly preferably star-shaped.

[0034] In a further development of the invention, it is conceivable for the inner skeleton and the cover to be detachably connected to one another. This allows for easy repair of the cover when disassembled or by replacing it. If the cover is damaged, it can be easily detached from the inner skeleton. Furthermore, it is ensured that the inner skeleton and / or the hub are easily accessible. In particular, if the inner skeleton is designed with a rim, as described elsewhere, the detachable connection facilitates repair of a tire that is clamped to the rim. Tire damage is common, especially when cycling, so a simple repair option is particularly advantageous.

[0035] The term "detachable" refers to a joint that can be separated, possibly with the aid of tools and / or solvents, without damaging the components being joined—in this case, the internal skeleton and the veneer. Any elements forming the joint may be irreversibly damaged during separation.

[0036] Particularly preferably, the inner skeleton and the veneer are connected by means of an adhesive connection which can be released by solvents known to the person skilled in the art, an adhesive tape, a Velcro fastener, a magnetic connection and / or screws.

[0037] Alternatively, it is conceivable that the inner skeleton and the veneer are permanently bonded together. This offers the advantage of a very durable and permanent connection, ensuring high integrity and strength of the disc wheel. In particular, it is conceivable that the inner skeleton and the veneer are bonded using a one-component or two-component adhesive.

[0038] Furthermore, it is conceivable for the disc wheel to comprise at least two facings. The two facings are placed on the inner skeleton of the disc wheel from both sides in an axial direction. They thus enclose the inner skeleton from both sides, providing optimal protection. It is also conceivable to achieve this effect with additional facings, each arranged on one of the sides and together forming a closed surface. The use of multiple facings enables the targeted replacement of individual parts while retaining the remaining components if one facing is damaged. The disc wheel particularly preferably comprises at least 3, 4, 5, 6, 7, 8, 9 or 10 facings.

[0039] It is also conceivable that the weight of the facing or facings is between 15% and 35% of the total weight of the disc wheel, preferably between 20% and 30%, and more preferably between 25% and 30%. The aforementioned measures make it possible to reduce the weight of the disc wheel. It has been shown that, taking these measures and the embodiments described elsewhere into account, the total weight of the facing or facings falls within a range of 15% to 35% of the total weight. This allows for optimal weight reduction.

[0040] Furthermore, it is conceivable that the weight of the inner skeleton is between 65% and 85% of the total weight of the disc wheel, preferably between 70% and 80%, and more preferably between 70% and 75%. The aforementioned measures make it possible to reduce the weight of the disc wheel. It has been shown that, by observing these measures and the embodiments described elsewhere, the weight of the inner skeleton falls within a range of 15% to 35% of the total weight. This allows for optimal weight reduction.

[0041] Furthermore, it is conceivable that the weight of the disc wheel is a maximum of 1,000 g, based on a 28-inch disc wheel. If at least the embodiment according to the invention is used, and in addition some or all of the embodiments presented in the subclaims, where possible, it is possible for the disc wheel to weigh a maximum of 1,000 g. Further preferably, the disc wheel weighs, based on a disc wheel with a size of 28 inches, a maximum of 990 g, 980 g, 970 g, 960 g, 950 g, 940 g, 930 g, 920 g, 910 g, 900 g, 890 g, 880 g, 870 g, 860 g, 850 g, 840 g, 830 g, 820 g, 810 g, 800 g, 790 g, 780 g, 770 g, 760 g, 750 g, 740 g, 730 g, 720 g, 710 g, 700 g, 690 g, 680 g, 670 g, 660 g, 650 g, 640 g, 630 g, 620g, 610g, 600g, 590g, 580g, 570g, 560g, 550g, 540g, 530g, 520g, 510g or 500g.

[0042] Further details, features, and advantages of the invention will become apparent from the following description of the preferred embodiment in conjunction with the subclaims. The respective features can be implemented individually or in combination with one another. The invention is not limited to the exemplary embodiment. The exemplary embodiment is illustrated schematically in the figures. The same reference numerals in the individual figures denote the same elements.

[0043] In detail: Fig. 1 is a perspective view of a first embodiment of a disc wheel according to the invention; Fig. 2 a perspective view of the first embodiment of the disc wheel according to the invention, without one of the facings; Fig. 3 a first perspective sectional view of the first embodiment of the disc wheel according to the invention, without one of the facings; and Fig. 4 a second perspective sectional view of a disc wheel according to the invention.

[0044] Fig. 1 shows a perspective view of a first embodiment of a disc wheel 01 according to the invention. The disc wheel comprises a hub 02 by means of which the disc wheel 01 can be attached to a vehicle (not shown), in particular to a vehicle axle (not shown). Furthermore, the disc wheel 01 comprises an inner skeleton 03, which is covered by two facings 07. The facings 07 are located opposite one another on axially opposite sides of the inner skeleton 03 of the disc wheel 01. The Fig. 1 The cover 07 shown in the front includes a recess 08 in addition to the recess for the hub 02. The covers 07 completely cover and enclose the inner skeleton 03. The inner skeleton 03 is thus protected from external influences. The covers 07 are designed as flat and thin discs.

[0045] Fig. 2 shows a perspective view of the first embodiment of the disc wheel 01 according to the invention, without the Fig. 1 first facing 07 shown in the front. The Fig. 1 and the Fig. The second cover 07 shown at the rear in Figure 2 is still visible. This reveals the inner skeleton 03. The inner skeleton 03 has six spokes 04 that engage the hub 02 with a tangential component. The inner skeleton 03 is made of a fiber composite material. The inner skeleton 03 further comprises a rim 05, which is monolithic with the inner skeleton 03. The rim 05 serves to accommodate a tire (not shown). During intended use, weight is transferred via the hub 02 to the spokes 04 and then to the rim 05, with the weight from the rim 05 being transferred to the ground via the tire (not shown).

[0046] Fig. 3 shows a first perspective sectional view of the first embodiment of the disc wheel 01 according to the invention, without the Fig. 1 front shown first facing 07. The second facing 07 is in the Fig. 3. The sectional plane of the sectional view extends in the radial and axial direction. It can be seen that the inner skeleton 04 comprises two cavities 06. The first cavity 06 extends around the part of the inner skeleton 03 that accommodates the hub (not shown) and in the spokes 04. The second cavity 06 extends within the rim 05. The cavities 06 allow the inner skeleton 03 to be designed to be light, yet stable. The inner skeleton 03 is therefore suitable for transmitting forces, in particular weight forces and / or frictional resistance forces, which arise in particular from airflow, from the vehicle to a tire (not shown). Fig. 3 clearly shows that the cover 07 protects the inner skeleton 03 from lateral interference. Another function of the cover 07 is to reduce and / or prevent turbulence and driving resistance on the disc wheel 01.

[0047] Fig. 4 shows a second perspective sectional view of the first embodiment of a disc wheel 01 according to the invention. The sectional plane extends in the radial direction and in the circumferential direction. Fig. 4, the two cavities 06 are particularly clearly visible. The first cavity extends into the spokes 04, and the second cavity 06 extends within the rim 05. The cover 07 covers the inner skeleton 03. The sectional view reveals only one of the two covers 07, which are arranged on both sides of the inner skeleton 03 in the axial direction. List of reference symbols 01 Disc wheel 02 Hub 03 Internal skeleton 04 Spoke 05 Rim 06 Cavity 07 Veneer 08 Recess QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 2 674 304 A1

[0003] EP 0 362 509 A1

[0004]

Claims

[1] Disc wheel (01) comprising a hub (02), an inner skeleton (03) surrounding the hub (02) with at least two spokes (04) and at least one cover (07), characterized by that the inner skeleton (03) is at least partially made of a fiber composite material. [2] Disc wheel (01) according to claim 1, characterized by that the inner skeleton (03) comprises a rim (05). [3] Disc wheel (01) according to claim 1 or 2, characterized by that the inner skeleton (03) is designed in one piece, in particular monolithic. [4] Disc wheel (01) according to one of the preceding claims, characterized by that the inner skeleton (03) encloses at least one cavity (06). [5] Disc wheel (01) according to one of the preceding claims, characterized by that the veneer (07) is made of a fiber composite material. [6] Disc wheel (01) according to one of the preceding claims, characterized bythat the inner skeleton (03) comprises between three and ten spokes (04). [7] Disc wheel (01) according to one of the preceding claims, characterized by that the inner skeleton (03) and the hub (02) are connected by a material connection. [8] Disc wheel (01) according to one of the preceding claims, characterized by that the inner skeleton (03) and the veneer (07) are detachably connected to each other. [9] Disc wheel (01) according to claim 8, characterized by that the inner skeleton (03) and the veneer (07) are connected by means of an adhesive connection, an adhesive tape, a Velcro fastener, a magnetic connection and / or screws. [10] Disc wheel (01) according to one of claims 1 to 7, characterized by that the inner skeleton (03) and the veneer (07) are inseparably connected to each other. [11] Disc wheel (01) according to claim 10, characterized bythat the inner skeleton (03) and the veneer (07) are connected by means of a one-component adhesive or a two-component adhesive. [12] Disc wheel (01) according to one of the preceding claims, characterized by that the disc wheel (01) comprises at least two facings (07). [13] Disc wheel (01) according to one of the preceding claims, characterized by that the weight of the facing (07) or facings (07) is between 15% and 35% of the total weight of the disc wheel (01). [14] Disc wheel (01) according to one of the preceding claims, characterized by that the weight of the inner skeleton (03) is between 65% and 85% of the total weight of the disc wheel (01). [15] Disc wheel (01) according to one of the preceding claims, characterized by that the weight of the disc wheel (01) is a maximum of 1,000 g.

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