Main frame, front fork and bicycle frame equipped with the same

Abstract

The present invention relates to a main frame (1) for a bicycle having a saddle and front and rear wheels arranged in a row, the main frame being manufactured in a closed mold from a thermoplastic resin, the main frame being in the form of a single-piece hollow article (2) having a frame wall portion (3) surrounding its cavity, the frame wall portion (3) of the hollow article (2) consisting of a single piece manufactured by rotational molding in a rotatable mold that can be heated from the outside. The present invention also relates to a front fork and a bicycle frame comprising the main frame and the front fork.

Description

Technical Field

[0001] The present invention relates to a bicycle frame for a bicycle having a saddle and front and rear wheels arranged on a single running track, and relates to its main components, in particular the main frame and the front fork.

Background Art

[0002] First, the present invention relates to a main frame manufactured from a thermoplastic in a closed mold. Second, the present invention relates to a front fork manufactured from a thermoplastic in a closed mold.

[0003] Furthermore, the present invention relates to a main frame for a bicycle having a saddle and front and rear wheels arranged on a single running track and manufactured from a thermoplastic. The main support and the one-sided rear wheel support are integrally formed, and the rear wheel support is designed as a hollow body on condition that the rear wheel support forms a closed housing for the drive means and that a rear wheel receiver is provided on the rear wheel support.

[0004] The present invention further relates to a front fork integrally formed from a thermoplastic for a bicycle having a saddle and provided with front and rear wheels arranged on a single running track. The front fork comprises a fork leg provided on one side and having an upper end and a lower end, or two such fork legs arranged symmetrically. Receiving openings are provided at the lower end of the fork leg or at both lower ends of the two fork legs, and the receiving openings are adapted to hold the front axle.

[0005] Compared with steel and aluminum, the strength of thermoplastic plastics is low as a material for bicycle frames. Its elastic modulus is lower than that of steel and aluminum. Similarly, the dimensional stability of plastics is also low. As is well known from Patent Document 1, this must be taken into account in the construction of the main frame and front fork from plastics.

[0006] The prior art has already proposed a bicycle frame made of thermoplastic plastic, which comprises a main frame and a front fork manufactured by an injection molding method, so-called thermoplastic injection molding. The well-known injection-molded main frame is provided with a rear wheel support having reinforcing ribs, and the front fork is reinforced by longitudinal ribs. In this prior art, the low strength of the plastic will be compensated by this reinforcement design.

[0007] The design of the main frame with ribs and the front fork with longitudinal ribs is considered to be complicated, and the achievable strength characteristics are considered to be insufficient.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Summary of the Invention

[0009] The object of the present invention is to develop a bicycle frame so as to provide a main frame and / or a front fork with a simple design both spatially and physically, which can give the strength and durability required for the bicycle frame and the above main components.

[0010] According to the present invention, this problem is achieved by the main frame of claim 1, which is designed as an integral hollow body having a frame wall portion surrounding a cavity, and the frame wall portion of the hollow body has an integral nature and is produced by rotational molding in an externally heatable rotating mold.

[0011] Regarding rotational molding, the thermoplastic material is injected into the rotating mold in powder form and is sealed all around for the molding process. The rotating mold has an inner wall, which forms a negative of the shape to be molded. It is advantageous if the rotating mold is formed as a permanent mold, usually made of metal, preferably aluminum. For the molding process, the rotating mold is rotatable about at least one axis and is externally heated. The plastic powder melts therein and can be dispersed over the entire inner wall in a viscous state as a melt. Finally, the melt solidifies on the inner wall of the rotating mold and can then be removed as the final hollow body when the rotating mold is opened.

[0012] For the main frame of a single-track bicycle, a shape with high dimensional accuracy is required. The inventor has discovered that it is advantageous for the main frame of a bicycle if the plastic material that is already expanding in the mold during solidification can expand freely in the hollow rotating mold. In this way, a main frame molded with low distortion can be provided, which has the dimensional accuracy required for a single-track bicycle and has less warping than an injection-molded main frame. The injection-molded main frame accumulates stresses that lead to warping because it cannot expand at all in the injection mold. Furthermore, the rotationally molded main frame has no joints due to its integral nature and has increased strength.

[0013] It is advantageous if the hollow body has regions of different wall thicknesses of the frame wall portion. In this way, the main frame can be adapted without inner ribs such that the points on the frame wall portion of the main frame that are particularly stressed during the riding operation can be reinforced by additional material to reduce cracks and breakages at these points.

[0014] It is advantageous if regions of different wall thicknesses of the frame wall are produced by different external heat inputs into the rotary die depending on the region. In the regions that are heated more strongly, the powder melts faster and can build up a greater wall thickness over the course of the process to provide the required strength. Surprisingly, it has been found that low stresses are possible even for main frames having different wall thicknesses of the frame wall, which can provide the required dimensional accuracy.

[0015] By means of the rotary die, separate components during the molding process that are connected to the hollow body can also be integrated into the molding process in an adhesive and / or positive locking manner. These can be metal components, for example rods, screws, rings or tubes, which can complement and reinforce the main frame.

[0016] It is beneficial if the thermoplastic of the frame wall is selected from one of the following plastics: polypropylene (PP), preferably polyethylene (PE), particularly preferably high density polyethylene (HDPE). Economic cycles in which these plastics can be recycled and provided in a form prepared for reuse already exist for each of the above-mentioned plastics. For this purpose, these plastics are recovered, for example, from the ocean and from agriculture. These plastics are found in fishing nets, bottom trawls, aquaculture nets, or as net wrapping for bundling straw bales, and further as scaffolding nets for protecting users on the road. The direct recovery of the above-mentioned plastics from consumer goods that are returned into the cycle without previously polluting the environment is highly promoted in the case of the proposed bicycle frame and its main components.

[0017] If the thermoplastic does not contain fibers, it is very suitable for reuse. In the context of the present invention, this can also include thermoplastics as long as they are sufficiently low in fibers to be processed for suitability for rotational molding.

[0018] Furthermore, if the main frame includes a sealed housing for the drive means, as defined in claim 6, the main support also achieves the potential problems in the case where the main support has opposing frame wall portions and is designed to be overall hollow and integrated with the rear wheel support. Compared with the main frame known from German Patent Invention No. 3804342, the proposed main support does not require ribs and is instead designed as a hollow body having overall opposing frame wall portions. This design is achieved by various manufacturing methods. These include shaping tools that can also process thermoplastic plastics or methods mainly for shaping, such as by 3D printing. The overall design of the main support, which is a hollow body and integrated with the hollow rear wheel support, is considered to be the present invention.

[0019] The rear wheel receiver is preferably formed as two coaxial bearing openings, and the coaxial bearing openings are arranged in the opposing frame wall portions of the rear wheel support. The bearing openings of the rear wheel support are located on the left side in the riding direction of the main frame, and the rear wheel is arranged in a rideable state of the bicycle. The said side of the rear wheel support is referred to as the wheel side, and the opposite side of the rear wheel support is referred to as the drive side. The bearing openings are preferably adapted to receive a shaft bearing for the rear wheel shaft. The bearing openings provided on the wheel side and / or the drive side are preferably formed in a hollow cylindrical shape and have an arrangement surface for bearing elements in the axial direction. The diameter of the hollow cylindrical bearing opening is preferably in the range of 40 mm to 130 mm. It is advantageous that the diameter of the hollow cylindrical bearing opening is larger on the wheel side than on the drive side of the rear wheel support.

[0020] The main frame having a sealed housing for the drive means is also considered to be particularly beneficial when the frame wall portion of the hollow body has an integral nature and is produced by rotational molding in an externally heatable rotating mold, as described above.

[0021] Furthermore, this hollow body may also have regions of different wall thicknesses in the frame wall portion. This can be achieved by rotational molding or, for example, by 3D printing.

[0022] As described above, thermoplastic plastics such as polypropylene (PP), preferably polyethylene (PE), and particularly preferably high-density polyethylene (HDPE) can be selected for this purpose. An economic cycle suitable for rotational molding or 3D printing, which allows these plastics to be recycled and provided in a form ready for reuse, already exists for each of the above-mentioned plastics. As described above, if the thermoplastic plastic does not contain fibers, it is also very suitable for reuse. In the context of the present invention, this also means low-fiber plastics if they are processable and suitable for rotational molding or 3D printing.

[0023] When rotational molding is provided, regions of different wall thicknesses in the frame wall portion can also be generated here, as described above, by different external heat inputs to the rotational mold depending on the region.

[0024] It is advantageous if a coaxial bearing opening for receiving the pedal drive is provided in the opposing wall portion region of the main support.

[0025] It is convenient if one of the bearing openings for the pedal drive also serves as a maintenance opening for the rear wheel support formed as a sealed housing for the drive means.

[0026] A further advantage can be that the main support is formed as a trapezoidal structure comprising a top tube element, a down tube element, a seat tube element, and a head tube element. Since the main support is hollow as a whole, all of the above tube elements of the trapezoidal structure form the hollow region of the main support.

[0027] A further improvement defines that the trapezoidal structure has a reinforcing bridge element arranged between the top tube element and the down tube element.

[0028] The seat tube element may have an upper seat tube extension that protrudes beyond the top tube element.

[0029] The rear wheel support has a triangular structure. This structure includes the aforementioned seat tube element as well as an upper support element and a lower support element. Thus, the seat tube element is an integral component of both the main support and the rear wheel support, and it practically forms the boundary between the main support and the rear wheel support.

[0030] In this embodiment of the main frame, the left side in the riding direction of the main frame is referred to as the wheel side, the right side is referred to as the drive side, and it is also referred to as the rear wheel support. In the latter case, the rear wheel is arranged to be attached to one of the wheel sides in the rideable state of the finished bicycle.

[0031] When the lower support element of the rear wheel support is designed as a housing for the drive means, it converges with the seat tube element at the front end of the lower support element. This area is adapted to receive the aforementioned pedal drive. There is space for a bottom bracket, a bottom bracket gearbox or a bottom bracket drive that may include an electric motor.

[0032] A reinforcing bridge element extending from the top tube element to the seat tube extension may be additionally provided. The bridge element reinforces the main frame. The seat tube extension is supported. Furthermore, the bridge element serves as a design element and may also function as a grip element for lifting the bicycle as needed and making it easily transportable.

[0033] It is advantageous for the main frame to have an envelope volume in the range of 18 liters to 22 liters, preferably in the range of 19 liters to 21 liters, and particularly preferably in the range of 20 liters to 20.5 liters.

[0034] The envelope volume of the main frame in the sense of the present invention means the volume of the outer surface of the main frame on the condition that all existing openings are interpreted as closed regions of the surface and are due to the outer surface. In particular, this means that the outer surface defining the envelope volume includes the openings of the rear wheel receiver, the area of the pedal drive receiver, and the openings of the areas of the head tube element and the seat tube element.

[0035] Furthermore, when looking at the above envelope volume individually or in combination, it is advantageous for the main frame to have a weight in the range of 3.5 kg to 5.5 kg, preferably in the range of 4.0 kg to 5.0 kg, particularly preferably in the range of 4.5 kg to 4.9 kg.

[0036] It is convenient for the main frame to have a specific gravity in the range of 0.16 kg / liter to 0.32 kg / liter with respect to its envelope volume.

[0037] The plastics proposed for the main frame, for example, polyethylene (PE or HDPE), have relatively low strength, hardness and rigidity. For other technical products, such polyethylenes are often reinforced by reinforcing fillers such as fibers. For the sake of recyclability, the present invention eliminates fiber reinforcement and selects homogeneous plastics. In order to give strength to the bicycle frame, the solution means is a main frame designed with an increased hollow body. Its volume is very large compared to well-known bicycle frames made of steel or aluminum, and furthermore, it is larger than the volume of a bicycle frame / main frame made of fiber-reinforced plastic. When the strength is further increased, a foam may be at least partially provided in the inner volume part of the hollow body.

[0038] It is convenient for the foam to be generated by foaming within the inner volume part of the hollow body.

[0039] The main frame is preferably adapted to have no cracks or breakage after an impact test with a drop weight of 22.5 kg from a drop height of 180 mm in accordance with the requirements of DIN-ISO 4210-6:2015, Chapter 4.1 and DIN-ISO 4210-2:2015, Chapter 4.8.2 for city and trekking bicycles.

[0040] The main frame is further preferably adapted to have no cracks or breakage after 100,000 test cycles after a dynamic test with a pedal force F of 1000 N in accordance with the requirements of DIN-ISO 4210-6:2015, Chapter 4.3 and DIN-ISO 4210-2:2015, Chapter 4.8.4 for city and trekking bicycles. 1

[0041] The main frame is capable of being adapted to have no cracks or breakage after 100,000 test cycles after a dynamic test with a horizontal force F of 450 N in the riding direction and a horizontal force F of 450 N in the direction opposite to the riding direction in accordance with the requirements of DIN-ISO 4210-6:2015, Chapter 4.4 and DIN-ISO 4210-2:2015, Chapter 4.8.5 with an exchange fork installed. 2 and a horizontal force F of 450 N in the direction opposite to the riding direction 3

[0042] Furthermore, the main frame is capable of being adapted to have no cracks or breakage after 50,000 test cycles after a dynamic test with a vertical force F of 1000 N in accordance with the requirements of DIN-ISO 4210-6:2015, Chapter 4.5 and DIN-ISO 4210-2:2015, Chapter 4.8.6. 4

[0043] ​​​It is particularly useful if a data storage element, preferably an RFID storage element, is provided on the main frame in order to store items of material information and / or data relating to the manufacture of the main frame, in particular relating to the plastic materials used. When the bicycle returns to the economic cycle at the end of its life, the stored items of information can serve to process and recycle the plastic as a homogeneous raw material.

[0044] Each main frame is adaptable to operate the rear wheel by means of a drive means designed as a traction mechanism having a tight strand and a slack strand, for example a bicycle chain or a toothed belt. In case such a drive means requires a specific tension in the tight strand and / or the slack strand, the main frame is provided with means for applying tension. The means may be a tensioning element or simply a measure on the main frame for fastening the tensioning element.

[0045] To achieve the object, the front fork is used when formed as a hollow fork body having a fork wall portion, and the fork wall portion of the hollow fork body has an integral nature produced by rotational molding in an externally heatable rotating mold.

[0046] The front fork is advantageously formed such that the hollow fork body has regions of different wall thicknesses of the fork wall portion.

[0047] There is a further advantageous effect when regions of different wall thicknesses of the fork wall portion are produced on the front fork by different external heat inputs into the rotating mold depending on the region.

[0048] The advantageous effects of the production by different wall thicknesses of the fork wall portion and the targeted heat input correspond in principle to the above-mentioned advantageous effects of the rotationally molded main frame when the main frame has different wall thicknesses of the frame wall portion. These advantageous effects are referred to and they apply equally to the front fork.

[0049] Furthermore, when the front fork has a fork leg provided on one side or has two symmetrically arranged fork legs, a fork bridge region to which an upward-facing fork arm is attached on one side or two symmetrically arranged upward-facing fork arms are attached is formed at the upper end of the fork leg, thereby achieving the object.

[0050] It is advantageous that a fork shaft that can be rotatably and fixedly connected as a metal tube and can be replaced is provided in the fork bridge region at the center of the fork bridge. Alternatively, the fork shaft can be arranged in a rotary die in order to be connected to a hollow fork body as an integral component of the front fork.

[0051] It is useful that the fork arm has an upper end and the upper end of the fork arm is connected to a handlebar element.

[0052] It is advantageous that the handlebar element is integrally formed as part of the hollow fork body.

[0053] The handlebar element may further have a left handlebar split body and a right handlebar split body that are divided in the center and each of which is connected to a corresponding left or right fork arm. The splitting of the handlebar element simplifies the installation of the front fork. For this purpose, it is advantageous that the fork arms are formed so as to be elastically expanded away from each other. Thereby, the handlebar split bodies can be moved sufficiently away from each other so that the front fork or its fork shaft can be inserted into the headset of the bicycle frame. Thereafter, the fork arms rebound and return to be fixed.

[0054] It is advantageous if the connection system is provided for fixation. It is beneficial if the handlebar split body is designed as part of the connection system. For this purpose, each of the handlebar split bodies is provided with upward and downward conical pieces. It is convenient if these two conical pieces belonging to one handlebar split body are integrally formed with the handlebar split body. It is convenient if the conical pieces of the two handlebar split bodies form a double conical element when they are fitted to each other. Thereby, the double conical element is divided in a vertical plane and has one double conical surface positioned on each handlebar split body. The double conical surface is preferably an integral component of the hollow fork body.

[0055] Furthermore, it is useful if a lower cup-shaped clamping element is provided. It is placed on the fork shaft and preferably has a conical inner surface. The inner surface is preferably adapted to be in close contact with the downward conical pieces of the two handlebar split bodies when the handlebar split bodies are fitted to each other at the center to form the above-mentioned double conical element.

[0056] Similarly, a cover-shaped upper clamping element may be provided. Advantageously, it can seal the free end of the fork shaft. In a simple form, a conical inner surface is also provided. The inner surface is preferably adapted to be in close contact with the upward conical pieces of the two handlebar split bodies when the handlebar split bodies are fitted to each other at the center.

[0057] The upper clamping element may further be provided with a through opening for an adjustment screw that can project into the fork shaft and be screwed into a nut element, as is generally the case with an Ahead headset.

[0058] By means of the adjustment screw, on the one hand, the handlebar split body is accurately fixed and, at the same time, connected to the fork shaft. Furthermore, the axial play of the headset can be adjusted by the adjustment screw.

[0059] Therefore, the proposed connection system is adapted to be able to perform both the connection of two handlebar split bodies using a single adjustment screw and its fastening to the fork shaft. Furthermore, it is useful if the receiving opening of the fork leg provided for holding the front axle forms a downwardly open dropout into which the front axle can be inserted from the side.

[0060] It is advantageous if a closing element is provided that can close the downwardly open dropout.

[0061] The closing element can be a separate component from the hollow fork body. Therefore, it is possible to use a different plastic material for the closing element and a manufacturing method different from that used for the hollow fork body.

[0062] Preferably, at least one connecting means for fastening the closing element to the fork leg is provided, as a result of which the front axle can be fixed. The fixing can be carried out in the manner of a positive lock and / or a force fit. In a simple embodiment, the dropout and the closing element have the shape of a semi-cylindrical shell, with a clamping slot remaining therebetween. And the closing element can be fastened to the dropout by means of screws as the connecting means. For this purpose, it is advantageous if at least one screw insertion part, preferably two screw insertion parts, is provided in the region of the dropout in the hollow fork body. Correspondingly, at least one push-through opening or two push-through openings for the screws are provided in the closing element. In this way, a receiving opening capable of generating a clamping action for fixing the axle element is formed.

[0063] It is particularly advantageous if the front fork has an envelope volume in the range of 3.5 liters to 6.5 liters, preferably in the range of 4.5 liters to 5.5 liters, and particularly preferably in the range of 4.7 liters to 5.3 liters.

[0064] The envelope volume of the front fork in the sense of the present invention means the volume of the outer surface of the front fork, provided that all existing openings are interpreted as closed regions of the surface and are due to the outer surface of the front fork, similar to the definition of the envelope volume of the main frame.

[0065] Furthermore, when looking at the above envelope volumes individually or in combination, it is advantageous for the front fork to have a weight in the range of 1.9 kg to 3.7 kg, preferably 2.4 kg to 3.2 kg, and particularly preferably 2.7 kg to 2.9 kg.

[0066] The front fork preferably has a specific gravity in the range of 0.29 kg / liter to 1 kg / liter with respect to its envelope volume.

[0067] A further advantage of this front fork can also be seen when the integral nature of the hollow fork body is produced by rotational molding in an externally heatable rotating mold.

[0068] The hollow fork body can have regions with different wall thicknesses of the fork wall.

[0069] Regions with different wall thicknesses of the fork wall can be produced by different external heat inputs into the rotating mold depending on the region.

[0070] Regarding this front fork, the advantageous effects of the generation by different wall thicknesses of the fork wall and the targeted heat input generally correspond to the above advantageous effects when the main frame has different wall thicknesses of the frame wall due to rotational molding.

[0071] It is very advantageous for the front axle to be positioned on the front fork as a structural component.

[0072] The front axle may comprise two cup-shaped or two hollow cylindrical axle elements, each axle element having a bearing seat for a wheel bearing and an engagement region for connection to the dropout of the fork leg. The bearing seat and the engagement region are arranged circumferentially. The engagement region has a cylindrical or polygonal cross-section, provided that the unit consisting of the dropout and the closure element has a matching hollow cylindrical or hollow polygonal cross-section. The front axle is arranged rotationally fixed relative to the remainder of the front fork. In the installed state, the front axle constitutes a structural reinforcement of the front fork.

[0073] In a simple embodiment, the two axle elements of the front axle can be interconnected in a row to provide an axle connection. Each axle element has a connection end. The axle connection can be produced by the connection ends.

[0074] It is advantageous if the connection ends of the two axle elements are formed such that the axle connection can be produced by a screw connection.

[0075] The screw connection has a separate screw and a separate nut, or an internal thread part is integrated into one of the axle elements and is capable of cooperating with the screw.

[0076] The screw connection is preferably provided by a connection end formed as an external thread part on the cylindrical outer surface of one of the axle elements, and the connection end of the other axle element is formed as a matching internal thread part. By this embodiment, the axle elements can be designed as hollow cylinders. Thereby, weight reduction is made possible. Furthermore, the hollow embodiment represents an attractive design element.

[0077] The front fork may be provided with a data storage element, preferably an RFID storage element, in order to store items of material information and / or data regarding the treatment of the plastic material preferably used for the front fork, similar to the main frame.

[0078] The plastic proposed for the front fork corresponds to that for the main frame. For example, in the case of polyethylene (PE or HDPE), they have relatively low strength, hardness and rigidity because they do not have reinforcing fillers such as fibers for recyclability, and instead homogeneous plastics are used. To give strength to the bicycle frame, the solution is also to design the front fork as a large hollow fork body. Its volume is very large compared to the volume of a well-known front fork made of steel or aluminum, and furthermore, it is larger than the volume of a front fork made of fiber-reinforced plastic, for example, a front fork made of carbon.

[0079] The present invention further comprises a bicycle frame for a bicycle having a saddle and front and rear wheels on a running track, and comprises the main frame according to any one of claims 1 to 25 and the front fork according to any one of claims 26 to 46.

[0080] It is advantageous for the front fork to have two fork legs. Thereby, a bicycle frame is provided in which a single-sided rear wheel support for the rear wheel is combined with a two-sided bearing for the front wheel.

[0081] In the bicycle frame, the main frame and the front fork constitute a unit in the installed state. When the unit is subjected to an impact test, in the case of a 200 mm drop height according to the requirements of DIN-ISO 4210-6:2015, Chapter 4.2 and DIN-ISO 4210-2:2015, Chapter 4.8.3 for city and trekking bicycles, a partial weight, in particular a 50 kg weight M for the seat tube element 1 , a 10 kg weight M for the test steering head 2 and a 30 kg weight M for the test bottom bracket 3 even after an impact test with a total drop weight of 90 kg consisting of, there are no cracks or damages in the unit.

[0082] Accordingly, the bicycle frames proposed herein, as well as the main frame and / or front fork respectively, are configured to be used in the economic cycle. For this purpose, the materials used to manufacture the main frame and / or front fork are thermoplastic plastics that are easily recyclable. Plastics are easily recyclable if deposited homogeneously. By being homogeneous, the pre-reuse treatment is facilitated and the circular economy is simplified. Thus, an old bicycle frame can, for example, be used as a raw material for manufacturing a new bicycle frame.

[0083] The proposed main frame and / or front fork promote the use of recyclable thermoplastic plastics. The proposed solution includes already using recycled plastics for the first manufacture.

[0084] Finally, other bicycle components are proposed from the group of the main frame, front fork and wheels. This bicycle component comprises a one-piece hollow body having a component wall portion surrounding its cavity, and the component wall portion of the hollow body is manufactured from thermoplastic plastic in a closed mold, with the additional condition that a foam is arranged in the cavity and the foam extends at least partially as a foam layer throughout the interior of the component wall portion or preferably completely fills the cavity, and has an integral property generated by rotational molding in an externally heatable mold provided for rotational molding.

[0085] The foaming process is advantageously carried out inside the cavity. The foaming process is preferably carried out when the thermoplastic for the rotational molding of the component wall is in a molten state and the rotational molding of the component wall is still in progress. The starting material of the foam is injected into the cavity forming part for foaming there using at least one suitable injection means provided in the mold. The starting material is easily injected into the same opening of the mold as the thermoplastic for the component wall in advance. A supply pipe insertable into the mold can be used. It can be inserted deep enough to penetrate the layer of molten thermoplastic already formed inside the mold. The injection of the foaming starting material can be easily carried out when the rotational movement of the mold is stopped. The rotational movement of the mold is advantageous not only in a circular movement but also in a complex three-dimensional movement in space. In order to inject the foaming starting material, for example, the components of the complex movement can be stopped so that the supply pipe can then be inserted into the injection means of the mold to inject the remaining foaming starting material into the cavity.

[0086] In principle, the foaming process may be a physical process or the foaming process is based on a chemical reaction. It is convenient if the starting material of the foam is injected in the form of a granular material using the injection means of the mold until it reaches the cavity forming part. For chemical foaming, the granular material of the starting material can be easily provided together with a foaming agent. The foaming agent is preferably designed to be evaporable through heat input. When the starting material also melts through heat input, the evaporated foaming agent can foam the molten starting material.

Brief Description of the Drawings

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Embodiments for Carrying Out the Invention

[0088] The present invention will be hereinafter illustrated by way of example in the drawings and will be described in detail with reference to several drawings.

[0089] FIG. 1 shows an embodiment of a main frame 1 according to the present invention for a bicycle ridden in an upright position having a saddle and front and rear wheels. These wheels are arranged on the same running track. The illustrated main frame 1 is manufactured as a hollow body 2 having a frame wall portion 3 surrounding a cavity. The hollow body 2 is integrally formed or is its frame wall portion 3. The integral main frame 1 is manufactured by rotational molding in an externally heatable rotating mold from a fiber-free thermoplastic, here homogeneously recycled high density polyethylene (HDPE). The frame wall portion 3 is provided with a data storage element 3c in which items of material information and / or data regarding the manufacture of the main frame, preferably information regarding the plastic material specifically used, are stored.

[0090] In order to provide the strength required for a bicycle frame, the main frame 1 is designed as a large hollow body 2. Its external volume is very large compared to the external volume of a well-known main frame made of steel, aluminum or carbon.

[0091] The main frame 1 includes a main support 4 and a single-sided rear wheel support 5 to which the rear wheel can be attached on only one side.

[0092] The structure of the main support 4 is a region T having a large wall thickness of the frame wall portion 3 1 , T 2 and T 3It has. Further, according to FIG. 1, it is formed in a trapezoidal shape. A top tube element 6, a down tube element 7, a seat tube element 8 and a head tube element 9 are provided. All of these tube elements of the trapezoidal structure are large and hollow, forming the region of the hollow main support 4. The down tube element 7 and the seat tube element 8 converge at the lower node 10 and form a pedal drive receiver 11 in the form of a closed pedal drive housing 12 there.

[0093] The head tube element 9 is arranged in front in the riding direction. It is adapted to receive a headset that cooperates with a fork shaft. The head tube element 9 is designed as a hollow cylinder. It is designed to receive a headset. The headset, for example, means a so-called front headset having a lower bearing arranged at the lower part of the head tube element 9, an upper bearing arranged at the upper part of the head tube element 9, and a tension device having an adjustment element for the fork shaft. The bearing play in the upper and lower bearings of the front headset can be adjusted by the tension device. Generally, the terms "lower part" and "upper part" in this description always refer to the main components of the bicycle frame when the bicycle is in an upright position, such as during the riding operation when the bicycle with the main components of the bicycle frame provided is moving straight forward.

[0094] The rear wheel support 5 has a triangular structure 13. This includes the aforementioned seat tube element 8 and upper support element 14 and lower support element 15. The seat tube element 8 practically forms the boundary between the main support 4 and the rear wheel support 5. The left side in the riding direction of the rear wheel support 5 is called the wheel side W, and the right side in the riding direction of the rear wheel support 5 is called the drive side D. The rear wheel is arranged on the wheel side W in the rideable state of the bicycle having this main frame.

[0095] The lower support element 15 of the rear wheel support 5 is designed as a housing 16 for the drive means. At the front end 15a of the lower support element 15, it converges with the downtube element 7 and the seat tube element 8 at the lower node 10. The area of the lower node 10 is designed as the aforementioned pedal drive housing 12. There is space in the pedal drive housing 12 for the bottom bracket, and furthermore, this space is alternatively sufficient for the bottom bracket gearbox. Alternatively, it is also possible to accommodate a bottom bracket drive which may include an electric motor.

[0096] The upper support element 14 of the rear wheel support 5 converges with the seat tube element 8 and the top tube element 6 of the main support 4 at the upper node 17. In the rear region 5a of the rear wheel support 5, the upper support element 14 and the lower support element 15 converge at the rear node 18, where the rear wheel carrier 19 is formed. The rear wheel carrier 19 is designed in the form of a bearing opening. The bearing opening 20 is provided on the wheel side W, and the bearing opening 21 is provided on the drive side D. The bearing openings 20 / 21 are adapted to receive a shaft bearing for a drive shaft (not shown) which rotates relative to the rear wheel support 5 and to which the rear wheel can be fastened. Alternatively, the bearing openings 20 and 21 are adapted to receive a rear axle (not shown) which is fixedly arranged relative to the rear wheel support 5, and as a result, the rear wheel attached to the rear axle rotates. The rear axle can be a standard rear axle.

[0097] Furthermore, the trapezoidal structure of the main support 4 is provided with a reinforcing hollow bridge element 22 arranged between the top tube element 6 and the downtube element 7. The bridge element 22 is arranged approximately parallel to and in the vicinity of the head tube element 9 according to FIG. 1. A polygonal open area 23 is provided between the bridge element 22 and the head tube element 9. The bridge element 22 thus formed reinforces the main support 4 of the main frame 1.

[0098] Furthermore, the sheet tube element 8 is provided with an upper sheet tube extension 24 that protrudes upward from the top tube element 6. A reinforcing hollow bridge element 25 that extends to the top tube element 6 is provided for the sheet tube extension 24. In this way, the sheet tube extension 24 is supported. Furthermore, the bridge element 25 serves as a grip element 26 for lifting the bicycle as needed and making it easily transportable.

[0099] Furthermore, FIG. 1 shows that a large maintenance opening 27 that enables access to a housing 16 for drive means that can be hermetically received in a lower support element 15 of the rear wheel support 5 for maintenance and installation purposes is provided on the drive side D in the region of the pedal drive housing 12.

[0100] FIG. 2 shows a view of the right side of the main frame 1, i.e., the drive side D. The pedal drive housing 12, where the large maintenance opening 27 is sealed here by a maintenance cover 28, is identified. The maintenance cover 28 is for a part where a bearing opening 29 is provided to receive a bearing element, for example, a crank arm.

[0101] On the left side of the main support 4, the pedal drive housing 12 may not have a maintenance cover, and here only a bearing opening 30 for the crank arm is provided so as to be most clearly distinguishable in FIG. 7. To provide stable bearing openings 29 and 30, the region T of the frame wall portion 3 1 is formed by reinforcement. The region T of the frame wall portion 3 that forms the head tube element 9 2 is likewise formed by reinforcement.

[0102] Figure 3 is a view of the main frame 1 from the back. It is identified that the rear wheel receiver 19 of the rear wheel support 5 protrudes most to the side of the drive side D (to the right side). This helps to provide sufficient space between the bearing opening 21 on the drive side D and the bearing opening 20 on the wheel side W in order to absorb the force / moment introduced into the rear wheel support 5 by the rear wheel arranged on one side. To enable the provision of stable bearing openings 20 and 21, the region T of the frame wall portion 3 3 is reinforced and formed.

[0103] Figure 4 is a top view of the main frame 1 according to FIG. 1, showing the position of the center line M of the main support 4. This center line M coincides with the running track on which the wheels of the bicycle are to be arranged. In the region of the rear wheel support 5, especially on the right side in the riding direction of the running track, its asymmetric one-sided position is shown. The frame wall portion 3 of the main frame 1 has two frame wall portions 3a and 3b facing each other. Also in the top view, it is identified that on the drive side D, the rear wheel receiver 19 of the rear wheel support protrudes most to the side of the drive side D. Further, it is shown that the pedal drive housing 12 is in line with the lower support element 15 of the rear wheel support 5. Further, the top view provides a view of the upper opening 31 of the head tube element 9 and the upper opening 32 of the seat tube element 8.

[0104] Figure 5 shows a cross-sectional view along the cutting line V-V of FIG. 2, particularly through the rear wheel receiver 19 of the rear wheel support 5 in the direction marked in the figure. Corresponding to this, two bearing openings are provided with the bearing opening 20 on the wheel side W. The second bearing opening 21 is arranged coaxially with the bearing opening 20, particularly on the opposite drive side D of the rear wheel support 5. The bearing openings 20 / 21 are adapted to receive a shaft bearing for a rear wheel shaft (not shown). The bearing openings are formed in a hollow cylindrical shape to receive the shaft bearing. In the axial direction, the bearing opening 20 has an inner positioning surface 33 that serves as an axial positioning surface for the bearing element. The cylindrical inner surface 33a serves as a seat that functions as a bearing element. The diameter of the bearing opening 20 and the quality of the inner surface 33a must be designed to match the desired bearing element, that is, within the specified tolerance range. The inner surface 33a can be a plastic surface. By means of a rotational molding method, a high-precision fitting bearing opening with a plastic surface can be manufactured. Alternatively, a metal ring prefabricated in a mode of high-precision fitting may be integrated during rotational molding. Alternatively, a high-precision fitting integrated aluminum ring 34 is shown by a dotted line in the region of the inner surface 33a. The aluminum ring 34 is connected to the plastic of the rear wheel support by adhesion and / or positive locking.

[0105] The bearing opening 21 arranged on the wheel side W has an inner positioning surface 35 and a cylindrical inner surface 35a. The dotted line in the region of the inner surface 35a shows an alternative example of an integrated high-precision fitting aluminum ring 36. The aluminum ring 36 is also connected to the plastic of the rear wheel support 5 by adhesion and / or positive locking.

[0106] The bearing opening 20 has a larger diameter than the bearing opening 20 provided on the drive side D. This is advantageous when the drive means arranged in the sealed housing 16 is arranged closer to the wheel side W, where greater forces are expected.

[0107] The diameters of the hollow cylindrical bearing openings 20 and 21 are preferably in the range of 40 mm to 130 mm. In this example, the bearing opening 20 on the wheel side has a diameter of 120 mm, and the bearing opening 21 arranged on the drive side D has a diameter of 90 mm.

[0108] FIG. 6 also shows a cross-sectional view taken along the cutting line V-V of FIG. 2, and the rear wheel support 19 together with the rear wheel 100 shown by a dashed line is shown using this cross-sectional view. In this example, a fixed solid rear axle 101 is provided. The single-sided rear wheel support 5 corresponds to that shown in FIG. 5, that is, it has bearing openings 20 and 21. A cylindrical disk element 102 provided with a through-opening 102a for the rear axle 101 is arranged in the bearing opening 21. The rear wheel 100 has a hub sleeve 103 that forms externally a seat 103a for the roller bearing 104, particularly for the inner ring of the roller bearing 104. The corresponding outer ring of the roller bearing 104 is installed in the rear wheel support 5, particularly in the bearing opening 20 of the rear wheel support 5. The hub sleeve 103 further has a hollow cylindrical inner space 105 that provides a space for the roller bearing 106 and for the freewheel element 107. A roller bearing 106 that needs to be axially preloaded is formed. The preload is provided by the rear axle 101 having screw ends 101a and 101b for applying preload to the screw ends 101a and 101b by the axle nuts 108 and 109.

[0109] A sprocket 112, which is part of the bicycle drive, is attached to the rear axle 101 by two roller bearings 110 and 111. In the installed state, the sprocket 112 cooperates with a bicycle chain (not shown) as a driving means, and the driving means is arranged within the rear wheel support 5. The rear wheel support 5 serves as a sealed housing 16 for the driving means and the sprocket 112.

[0110] As a result, the freewheel element 107 is connected between the sprocket 112 and the hub sleeve 103, enabling the transmission of the rotational movement only in one rotational direction of the rear wheel and allowing the transmission of torque.

[0111] In the example of FIG. 6, the rear wheel may be provided with, for example, a normal gear hub having a fixed axle. The axle may be a solid axle or, alternatively, a hollow axle.

[0112] FIG. 7 shows a cross-sectional view through the pedal drive receiver 11 of the main frame 1 along the cutting line VII-VII shown in FIG. 2. The pedal drive receiver 11 has a maintenance opening 27 on the drive side D that is adapted to receive a maintenance cover 28. The maintenance cover 28 preferably has a bearing opening 29 for a sliding bearing element 120 for attaching a crank arm (not shown). The sliding bearing element 120 has a diameter of 30 mm in this example. On the opposite side, the pedal drive receiver 11 has a bearing opening 30 for a bearing element (not shown) for the crank arm, preferably further capable of receiving a sliding bearing element. The maintenance opening 27 for the maintenance cover 28 is provided with a diameter of 120 mm in this example.

[0113] FIG. 8 also shows a cross-sectional view through the pedal drive receiver 11 of the main frame 1 along the cutting line VII-VII shown in FIG. 2. This is an alternative design of the pedal drive receiver 11 and differs in the modified bearing openings 121 and 122. Both of the bearing openings 121 and 122 have a large cross-section. They are both provided with a diameter of 120 mm in this example. The large bearing openings are, for example, for receiving roller bearings, and their inner ring and / or outer ring are manufactured from plastic. This embodiment enables, for example, the reception of a pedal drive for a pedal drive with a bottom bracket gearbox or a bottom bracket drive having an electric motor.

[0114] The main frame illustrated using FIGS. 1 to 4 has an envelope volume of 20.25 liters with a tolerance of ±0.25 liters. Its weight is 4.75 kg with a tolerance of ±0.2 kg.

[0115] FIG. 9 is a perspective view of a front fork 40 according to the present invention. The front fork is designed for a bicycle having a saddle and ridden in an upright position. The bicycle is provided with a front wheel and a rear wheel disposed on a running track.

[0116] The front fork 40 has a stable fork bridge region 41. Two fork legs 42 and 43 are symmetrically arranged in the fork bridge region and are directed downward. Further, a fork arm 44 or 45 extending to and connected to an integrated handlebar element 46 is attached to each fork leg at the upper part. A fork shaft 47 illustrated by a dashed line is provided at the center of the fork bridge. In this example, the fork shaft 47 is a metal tube rotatably and fixedly connected to the fork bridge region 41.

[0117] The handlebar element 46 is divided in the center and is clearly distinguishable. It has a left - hand handlebar split body 48 and a right - hand handlebar split body 49, each of which is connected to a corresponding fork arm. The division serves for easy installation of the front fork 40. The fork arms 44 and 45 are formed such that the handlebar split bodies 48 and 49 can be elastically spread apart from each other so that they can move sufficiently away from each other, thereby enabling the fork shaft 47 of the front fork to be inserted into the headset of the bicycle frame. Thereafter, the fork arms rebound and return and are finally fixed by a connection system shown in FIG. 11 and best shown in FIG. 17.

[0118] The proposed front fork 40 is manufactured from a thermoplastic in a closed rotary mold. It forms a hollow fork body 50 having fork wall portions 51. The hollow fork body 50 is integral and has no seams in its fork wall portions 51. In this example, as described above, only the fork shaft 47 is later inserted and connected into the fork bridge region 41 of the hollow fork body 50. The integral nature is produced by rotational molding in an externally heatable rotary mold, in particular from a fiber-free thermoplastic, here homogeneously recycled high density polyethylene (HDPE). The later inserted fork shaft 47 may alternatively be placed within the rotary mold so as to be connected to the thermoplastic of the hollow fork body 50 during the rotational molding process. In this way, the metal tube of the fork shaft is also later provided as an integral component of the front fork.

[0119] The fork arm 44 is provided with a dropout 52, and the fork arm 45 is provided with a dropout 53 for receiving the front axle. The front axle is a large diameter special front axle as indicated by the dropouts 52 and 53. The dropouts are formed to open downward, and as will be further described below, separate closing elements are provided for each dropout 52 / 53.

[0120] The fork leg 42 is further provided with fastening elements 54 that can be used, for example, to install a brake assembly, particularly for a brake caliper of a disc brake.

[0121] The hollow fork body 50 has regions of different wall thicknesses in the fork wall portions 51. The thicker wall regions of the fork wall portions 51 are produced by the heat input from the outside to the rotary mold, which is higher in those regions. In this example, the lower regions 42a and 43a of the fork legs 42 and 43 are provided with thicker wall fork wall portions.

[0122] The fork wall portion 51 is provided with a data storage element 51a that stores items of material information and / or data related to the manufacture of the front fork 40, preferably information regarding the plastic material specifically used.

[0123] The front fork 40 according to FIG. 10 has an envelope volume of 5 liters with a tolerance of ±0.15 liters, including the closing elements 55 and 57. Its weight is in the range of 2.4 kg to 3.2 kg with a tolerance of ±0.1 kg.

[0124] FIG. 10 shows a side view of the front fork 40. The closing element 55 is installed in the dropout 53 of the fork leg 43. The closing element 55 complements the dropout 53 and forms a receiving opening 56 for holding a special front axle together with it. Connecting means 55a and 57a in the form of screws (not shown) are provided for fastening the closing elements 55 and 57 to the fork legs 42 and 43 respectively. For the purpose of installation, the front axle can be inserted from the side or below and fixed to the closing element 55.

[0125] In this example, the closing element 55 provides a clamp connection that fixes the front axle to the dropout in a rotationally fixed manner. Instead of a clamp connection with a friction locking action, a positive locking (formschlussige) design may be provided to achieve the fixation by rotationally fixing the front axle within the receiving opening of the fork leg.

[0126] To provide the fixation in this example, screws are provided as the connecting means. Accordingly, the dropout is provided with an internal thread portion, and correspondingly, the closing element has a through-opening for the screw.

[0127] Figure 11 shows a cross-section along the cutting line XI-XI of Figure 9, and the fork shaft 47 is shown in the figure of Figure 11. The fork shaft 47 is held at the lower part of the fork bridge region 41 and held at the upper part by the connection system described above, which will be described in detail with reference to Figure 16. Further, Figure 11 shows a closing element 57 belonging to the dropout 52 of the fork leg 42, which results in forming a receiving opening 58 for the front axle.

[0128] As shown in Figure 12, a special front axle 59 is positioned on the front fork 40. The front axle 59 is a structurally important component for the proposed front fork 40. For a front fork 40 having a hollow fork body 50 made of homogeneous plastic, it is beneficial to provide the front axle 59 as a supplementary rigid component. Thereby, the strength of the front fork 40 can be significantly improved.

[0129] As shown in Figure 13, the front axle 59 comprises two cup-shaped and two hollow cylindrical axle elements 60 and 61. The two axle elements of the front axle are arranged in a row and connected to each other. For this purpose, connection ends 60a and 61a are respectively provided. The connection end 60a of the axle element 60 is provided with a male thread portion 62, and the connection end 61a of the axle element 61 has a matching female thread portion 63, and they are screwed together.

[0130] The axle element 60 has a bearing seat portion 64 for a wheel bearing. Further, the axle element 60 is provided with a cylindrical meshing region 65 for the purpose of connection to the dropout 52 of the fork leg 42. The meshing region 65 comprises side bars 65a and 65b as best distinguishable in Figure 14. The bars 65a and 65b have a mutual spacing corresponding to the thickness of the fork leg 42.

[0131] The fork leg 42 is fixed between the bars 65a and 65b. Similarly, the axle element 61 is provided with a bearing seat 66 for a wheel bearing, and the axle element 61 has an engagement region 67 for the purpose of connecting to the dropout 53 of the fork leg 43. The engagement region 67 is also provided with bars 67a and 67b. The bars also fix the fork leg 43 in the axial direction of the front axle 59.

[0132] The bearing seats 64 / 66 and the engagement regions 65 / 67 are arranged around the axle elements 60 / 61. In this example, the engagement regions 65 / 67 have a cylindrical cross-section and are clamped in the respective receiving openings 56 and 58 of the fork legs. In this way, the front axle 59 is arranged to be rotationally fixed with respect to the front fork 40 and serves as a structural stiffening element of the front fork 40.

[0133] FIG. 15 shows an alternative design of the dropout of the front fork for a standard axle. The fork legs 42 and 43 correspond to those in FIG. 14. Adapter elements 56a or 58a are arranged in each of the receiving openings 56 and 58 respectively. The adapter elements 56a and 58a are identical components. Each of them has a central opening 56b and 58b adapted to receive a standard axle. The central openings 56b / 58b are both slots. Thereby, the alignment of the front wheel at the center between the fork legs 42 and 43 can be adjusted.

[0134] FIG. 16 shows a detailed view along the cutting line XVI-XVI in FIG. 12. The handlebar split body 48 of the split handlebar element 46 and the fork arm 44 supporting this handlebar split body 48 are identified. In order to enable the front fork 40 to be installed on the headset element of the main frame, the fork arms 44 / 45 having the handlebar split bodies 48 / 49 located therein are spread apart from each other and rebound to return to the installed state. Thereafter, the handlebar split bodies are fixed to each other and fixed to the fork shaft 47 by a connection system 68.

[0135] The proposed connection system 68 is adapted to effect both the connection of the two handlebar split bodies 48 and 49 and its fastening to the fork shaft 47 by means of a single screw. It comprises a double - cone element 69 which is split in a vertical plane and forms two double - cone surfaces 70 and 71. The double - cone surface 70 is positioned on the handlebar split body 48 and the double - cone surface 71 is positioned on the handlebar split body 49. In this example, the double - cone surfaces 70 and 71 are integral components of the hollow fork body 50.

[0136] The double - cone surface 70 comprises an upward - facing conical piece 70a and a downward - facing conical piece 70b, and the double - cone surface 71 comprises an upward - facing conical piece 71a and a downward - facing conical piece 71b.

[0137] Furthermore, a lower cup - shaped clamping element 72 is provided which is arranged on the fork shaft 47. The inner surface 73 of the clamping element 72 is conical and abuts against the downward - facing conical pieces 70b and 71b of the two handlebar split bodies 48 / 49 in order to fix them.

[0138] Similarly, a cover - like upper clamping element 74 is provided for sealing the free end of the fork shaft 47. It has a conical inner surface 75. The inner surface 75 abuts against the upward - facing conical pieces 70a and 71a in order to fix them or to fix the split handlebar split bodies 48 / 49.

[0139] The upper clamping element 74 is provided with a through - opening 76 for an adjusting screw 77. The adjusting screw 77 projects into the fork shaft 47 and is screwed into a nut element 78 which can be fixed within the hollow cylindrical fork shaft 47 in a friction - locking manner. In this example, it is a nut 79 with a claw which can be fixed by an elastic claw 80.

[0140] By means of the adjusting screw 77, the handlebar split bodies 48 and 49 are accurately fixed and at the same time connected to the fork shaft 47. Furthermore, the axial play of the headset can be adjusted by the adjusting screw 77.

[0141] FIG. 17 shows a bicycle frame 81 including a main frame 1 and a front fork 40.

[0142] FIG. 18 shows a perspective view of an alternative bicycle component. By way of example, how the alternative bicycle component is configured and manufactured will be described with reference to the front fork. The example of the alternative bicycle component is based on the front fork of FIG. 9. According to FIG. 18, the bicycle component is designed as an integral hollow body, here as a hollow fork body 50 having a component wall portion surrounding the cavity thereof, here a fork wall portion 51. The fork wall portion 51 is manufactured from a thermoplastic plastic within a closed mold. The integral nature of the fork wall portion 51 is produced by rotational molding in an externally heatable mold provided for rotational molding. The alternative of FIG. 18 differs from the example of FIG. 9 in that a foam 125 filling the cavity in this example is further disposed within the hollow fork body 50.

[0143] The foaming process was carried out inside the cavity while the rotational molding of the fork wall portion 51 was still in progress with the thermoplastic plastic for the fork wall portion 51 in a molten state. The starting material of the foam was injected into the mold as a granular material by suitable injection means. The granular material used is foamable by a chemical reaction. For this purpose, it contains a blowing agent. In this example, the blowing agent is designed to evaporate through heat input. Through the heat input, the starting material is likewise melted and it then foams by the blowing agent that evaporates.

[0144] Figure 19 shows another example of an alternative bicycle component. By way of example, how the alternative bicycle component is configured and manufactured will also be described with reference to the front fork. This example is based on the drawing of the front fork in Figure 10. According to Figure 19, the bicycle component is again formed as an integral hollow body, here as a hollow fork body 50 having a component wall portion, particularly a fork wall portion 51. The fork wall portion 51 surrounds a cavity. It is manufactured from a thermoplastic in a closed mold. The integral nature of the fork wall portion 51 is again produced by rotational molding in an externally heatable mold for rotational molding.

[0145] The alternative example of Figure 19 differs from the examples of Figures 10 and 18 in that in this example, a foam 126 that coats the component wall portion of this bicycle component, particularly the fork wall portion 51, is further disposed within the hollow fork body 50 on its inside facing the cavity. Thereby, the cavity of the hollow fork body 50 is reduced but not eliminated.

Description of Reference Numerals

[0146] 1 Main frame 2 Hollow body 3 Frame wall portion 3a Frame wall portion 3b Frame wall portion 3c Data storage element 4 Main support 5 Rear wheel support 5a Rear region 6 Top tube element 7 Down tube element 8 Seat tube element 9 Head tube element 10 Lower node 11 Pedal drive receiver 12 Pedal drive housing 13 Triangular structure 14 Upper support element 15 Lower support element 15a Front end 16 Housing (Drive means) 17 Upper node 18 Rear node 19 Rear wheel receiver 20 Bearing opening 21 Bearing opening 22 Bridge element 23 Open area 24 Seat tube extension 25 Bridge element (Intermediate element) 26 Grip element 27 Maintenance opening 28 Maintenance cover 29 Bearing opening 30 Bearing opening 31 Upper opening (Head tube element) 32 Upper opening (Seat tube element) 33 Inner positioning surface (Bearing opening 20) 33a Cylindrical inner surface 34 Aluminum ring 35 Inner positioning surface (Bearing opening 21) 35a Cylindrical inner surface 36 Aluminum ring 40 Front fork 41 Fork bridge area 42 Left fork leg 42a Thick-walled area (Fork wall) 43 Right fork leg 43a Thick-walled area (Fork wall) 44 Left fork arm 45 Right fork arm 46 Handlebar element 47 Fork shaft 48 Left handlebar split body 49 Right handlebar split body 50 Hollow fork body 51 Fork wall 51a Data storage element 52 Dropout 53 Dropout 54 Fastening element 55 Closing element 55a Connecting means 56 Receiving opening 56a Adapter element 56b Central opening 57 Closing element 57a Connecting means 58 Receiving opening 58a Adapter element 58b Central opening 59 Front axle 60 Axle element 60a Connection end 61 Axle element 61a Connection end 62 Male thread part 63 Female thread part 64 Bearing seat part 65 Engaging region 65a Bar 65b Bar 66 Bearing seat part 67 Engaging region 67a Bar 67b Bar 68 Connection system 69 Double cone element 70 Double cone surface 70a Upper cone piece 70b Lower cone piece 71 Double cone surface 71a Upper cone piece 71b Lower cone piece 72 (Lower side) clamp element 73 Inner surface (lower side clamp element) 74 (Upper side) clamp element 75 Inner surface (upper side clamp element) 76 Through opening 77 Adjusting screw 78 Nut element 79 Nut with claw 80 Claw 81 Bicycle frame 100 Rear wheel 101 Rear axle 101a Threaded end 101b Screw end 102 Disc element 102a Through opening 103 Hub sleeve 103a Seating portion 104 Roller bearing 105 Hollow cylindrical internal space 106 Roller bearing 107 Freewheel element 108 Axle nut 109 Axle nut 110 Roller bearing 111 Roller bearing 112 Sprocket 120 Plain bearing element 121 Bearing opening 122 Bearing opening 125 Foam (foam filling material) 126 Foam layer D Driving side W Wheel side M Center line

Claims

1. A main frame (1) manufactured from thermoplastic in a sealed mold for a bicycle having a saddle and front and rear wheels arranged in a single trajectory, It is designed as a single hollow body (2) having a frame wall (3) surrounding the cavity, The frame wall portion (3) of the hollow body (2) is a main frame (1) having an integral nature, produced by rotational molding in a rotary mold that can be heated externally.

2. The main frame (1) according to claim 1, wherein the hollow body (2) has regions of different wall thicknesses in the frame wall portion (3).

3. The main frame (1) according to claim 2, wherein the regions of the frame wall portion (3) with different wall thicknesses are generated by different heat inputs from the outside into the rotating mold depending on the region.

4. The main frame (1) according to claim 1, wherein the thermoplastic of the frame wall portion (3) is selected from one of the following plastics: polypropylene (PP), polyethylene (PE), and high-density polyethylene (HDPE).

5. The main frame (1) according to claim 1, wherein the thermoplastic plastic is fiber-free.

6. A main frame (1) made of thermoplastic plastic for a bicycle having a saddle and front and rear wheels positioned along a single trajectory, The main support (4) and the one-sided rear wheel support (5) are integrally formed, the rear wheel support (5) is designed as a hollow body (2), the rear wheel support (5) forms a sealed housing (16) for the drive means, and the rear wheel support (5) includes a rear wheel receiver (19). The main support (4) is a main frame (1) which is designed to be hollow overall, having opposing frame wall portions (3a, 3b), and is designed to be integrated with the rear wheel support (5).

7. The rear wheel support (19) is formed as two coaxial bearing openings (20, 21), The main frame (1) according to claim 6, wherein the coaxial bearing openings (20, 21) are located on the opposing frame walls (3a, 3b) of the rear wheel support (5).

8. The main frame (1) according to claim 7, wherein the frame wall portion (3) of the hollow body (2) has an integral property produced by rotational molding in an externally heatable rotary mold.

9. The main frame (1) according to claim 8, wherein the hollow body (2) has regions of different wall thicknesses in the frame wall portion (3).

10. The main frame (1) according to claim 7, wherein the regions of the frame wall portion (3) with different wall thicknesses are generated by different heat inputs from the outside into the rotating mold depending on the region.

11. The main frame (1) according to claim 1, wherein at least a portion of the internal volume of the hollow body (2) is provided with foam.

12. A front fork (40) manufactured from thermoplastic in a sealed mold for a bicycle having a saddle and front and rear wheels arranged in a single trajectory, wherein at least one fork leg (42, 43) is provided, It is formed as a hollow fork body (50) having a fork wall portion (51), The fork wall portion (51) of the hollow fork body (50) is a front fork (40) which has an integral nature, produced by rotational molding in a rotary mold that can be heated externally.

13. The front fork (40) according to claim 12, wherein the hollow fork body (50) has regions of different wall thicknesses in the fork wall portion (51).

14. The front fork (40) according to claim 13, wherein the regions of the fork wall (51) with different wall thicknesses are generated by different heat inputs from the outside into the rotating mold depending on the region.

15. A front fork (40) made of thermoplastic plastic for a bicycle having a saddle and equipped with a front wheel and a rear wheel positioned in a single trajectory, The vehicle comprises either a fork leg (42, 43) provided on one side and having an upper and lower end, or two such fork legs (42, 43) arranged symmetrically, with receiving openings (56, 58) provided at the lower end of the fork leg or the lower end of the two fork legs (42, 43), and the receiving openings (56, 58) are adapted to hold the front axle (59), A front fork (40) in which an upward-facing fork arm (44, 45) is attached to one side, or a fork bridge region (41) is formed at the upper end of the fork leg (42, 43) to which two upward-facing, symmetrically arranged fork arms (44, 45) are attached.

16. The front fork (40) according to claim 15, wherein the fork arms (44, 45) have upper ends, and the upper ends of the fork arms (44, 45) are connected to a handlebar element (46).

17. Formed as a hollow fork body (50) having a fork wall portion (51), The front fork (40) according to claim 16, wherein the handlebar element (46) is integrally formed as part of the hollow fork body (50).

18. The front fork (40) according to claim 15, wherein the receiving openings (56, 58) of the fork legs (42, 43) provided for holding the front axle (59) form downward open dropouts (52, 53) into which the front axle (59) can be inserted from the side.

19. The front fork (40) according to claim 18, further comprising closing elements (55, 57) that allow the downward open dropouts (52, 53) to be closed.

20. Formed as a hollow fork body (50) having a fork wall portion (51), The front fork (40) according to claim 15, wherein the integral properties of the hollow fork body (50) are produced by rotational molding in an externally heatable rotary mold.

21. The front fork (40) according to claim 20, wherein the hollow fork body (50) has regions of different wall thicknesses in the fork wall portion (51).

22. The front fork (40) according to claim 21, wherein the regions of the fork wall (51) with different wall thicknesses are generated by different heat inputs from the outside into the rotating mold depending on the region.

23. The front fork (40) according to claim 15, wherein the front axle (59) is positioned as a structural component.

24. The front axle (59) comprises two cup-shaped or two hollow cylindrical axle elements (60, 61), Each axle element (60, 61) has a bearing seat (64) for the wheel bearing and a meshing area (65) for the purpose of connecting to the dropouts (52, 53) of the fork legs (42, 43). The front fork (40) according to claim 23, wherein the meshing region (65) has a cylindrical or polygonal cross-section, provided that the unit consisting of the dropouts (52, 53) and closing elements (55, 57) has a matching hollow cylindrical or hollow polygonal cross-section.

25. The two axle elements (60, 61) are interconnectable in a line to form an axle connection, Each axle element (60, 61) has a connecting end (60a, 61a), The axle connection portion can be generated by the connection ends (60a, 61a) of the front fork (40) according to claim 24.

26. A bicycle frame (81) for a bicycle having a saddle and a front wheel and a rear wheel in a single trajectory, comprising a main frame (1) as described in claim 1 and a front fork (40) in which at least one fork leg (42, 43) is formed as a hollow fork body (50) having a fork wall portion (51), and the fork wall portion (51) of the hollow fork body (50) is integrally formed by rotational molding in an externally heatable rotary mold.

27. The bicycle frame according to claim 26, wherein the front fork (40) has two fork legs (42, 43).

28. A bicycle component comprising a group of mainframe, front fork and wheel, comprising a single hollow body (50) having a component wall (51) surrounding a cavity, wherein the component wall (51) of the hollow body (50) is manufactured from thermoplastic in a sealed mold, and the component wall (51) has an integral nature produced by rotational molding in an externally heated mold designed for rotational molding, with the additional condition that a foam is placed in the cavity and the foam extends at least partially as a foam layer (126) throughout the entire interior of the component wall (51) or completely fills the cavity as a foam filler (125).

29. A method for manufacturing a main frame (1) for a bicycle in which the front wheel and rear wheel are arranged in a single trajectory, A thermoplastic material is placed into a rotating mold having the inverse shape of the main frame, Closing the aforementioned rotating mold, Heating the rotating mold from the outside while rotating it around at least one axis, Solidifying the aforementioned main frame, Opening the rotary mold and removing the main frame from the rotary mold, Includes, The main frame is designed as an integrated hollow body (2) having a frame wall portion (3) surrounding its cavity, and the frame wall portion (3) of the hollow body (2) has an integrated structure, in this method.

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