Method for producing a bicycle frame, injection mould and bicycle frame

Abstract

The invention relates to a method for producing a bicycle frame (210) from a thermoplastic material preferably reinforced with high-tensile fibres, wherein the method comprises the injection moulding of the bicycle frame (210) as a one-piece moulded part into a multi-part injection mould (100), and at least some of the frame tubes, preferably at least all of the frame tubes of the main frame, are moulded as continuous hollow profile sections, which are closed at least over a partial length, using a plurality of movable mould parts of the injection mould (100), in particular using a plurality of movable mould sliders, which can be moved from a demoulding position into a functional position within a moulded-part cavity (111) of the injection mould (100) and from the functional position into the demoulding position. The invention further relates to an injection mould (100) and to a bicycle frame (210) made of thermoplastic material.

Description

[0001] Method for manufacturing a bicycle frame, injection mold and bicycle frame

[0002] The invention relates to a method for manufacturing a bicycle frame from a thermoplastic material preferably reinforced with tensile fibers, wherein the method comprises injection molding the bicycle frame as a one-piece molded part into a multi-part injection molding tool.

[0003] The invention further relates to an injection molding tool, which is preferably designed for carrying out the method.

[0004] The invention relates to a bicycle frame made of a thermoplastic material preferably reinforced with tensile-strength fibers, as a one-piece injection-molded bicycle frame.

[0005] It is known in the art to manufacture bicycle parts, especially bicycle frames, from fiber-reinforced composite materials. In the course of weight optimization for bicycles, composite components made of carbon fiber are particularly widespread. Thermosetting plastics, especially epoxy resin, are predominantly used as matrix materials. Such bicycle frames are characterized by a particularly favorable stiffness-to-weight ratio. However, they have the disadvantage that the epoxy resin-based plastic can easily break, for example, in a fall. Furthermore, the recyclability of such frames or other components based on epoxy resin is less guaranteed. The fibers used in the manufacture of carbon fiber frames are generally bonded together as woven or non-woven fabrics according to a predetermined cut and placed manually into a mold.An epoxy resin-based plastic is typically introduced into the closed mold in such a way that the resin penetrates the fiber fabric or woven material. The component is then cured by applying heat. This manufacturing process is complex and requires a high degree of manual labor, both before the component is formed and in the form of the necessary finishing work.

[0006] It is also known in the art to manufacture bicycle parts, and in particular bicycle frames, from fiber-reinforced thermoplastic. Thermoplastics are easier to recycle than thermosetting plastics and can be molded, for example, by injection molding. The production of injection-molded frame components has the disadvantage that they must be designed in such a way that they can be easily removed from the injection mold. Therefore, known frames made of injection-molded thermoplastic are generally assembled from multiple parts.

[0007] In principle, thermoplastic structural components can also be produced as hollow profiles by extrusion blow molding or using fluid injection technology. These methods have the disadvantage that the structures produced do not have a defined wall thickness and, in particular, no smooth inner contour.

[0008] German patent DE 10 2016 015 538 A discloses a method for manufacturing a bicycle frame from several modules, each produced by injection molding using fluid injection technology. Fluid injection technology offers a process-wise advantageous way to form the individual components as hollow bodies with optimized weight. However, as mentioned above, such a method has the disadvantage that the components do not have a constant and defined wall thickness and, in particular, a consistently smooth surface within the cavities. This is not advantageous for various reasons. For example, it results in mass differences between components in a series.

[0009] The invention is therefore based on the objective of providing a method of the type mentioned at the outset, with which one-piece injection-molded bicycle frames made of thermoplastic material can be mass-produced while achieving a particularly favorable stiffness-to-weight ratio with respect to the bicycle frame.

[0010] The invention further aims to provide an injection molding tool suitable for carrying out the process, as well as a correspondingly production-optimized bicycle frame made of thermoplastic material.

[0011] The problem is solved by the features of the independent claims. Advantageous embodiments of the invention are described in the dependent claims.

[0012] A first aspect of the invention relates to a method for manufacturing a bicycle frame from a thermoplastic material preferably reinforced with tensile fibers, wherein the method comprises injection molding the bicycle frame as a one-piece molded part or one-piece article in a multi-part injection mold and at least some of the frame tubes, preferably at least all frame tubes of the main frame, are formed as continuous hollow profile sections closed at least over a partial length, using a plurality of movable mold parts of the injection mold, in particular using a plurality of movable mold slides, each of which is movable from a demolding position to a functional position within an article cavity of the injection mold and from the functional position to the demolding position.

[0013] In the context of the invention, a functional position of a mold slide or other movable tool part refers to the position in which the thermoplastic material is injected into the closed part cavity. After the injection-molded part has been formed, the movable tool parts are moved to a position outside the part cavity to ensure the part can be demolded. This position is hereinafter referred to as the demolding position. In the context of the present invention, a part cavity is defined as the cavity within the injection mold that forms the part, i.e., that is designed as a negative of the part. Consequently, gates, distributors, or the like are not part of the part cavity.

[0014] A main frame of a bicycle according to the present invention is that part of the bicycle frame which includes at least a seat tube, a bottom bracket shell or a motor housing, depending on whether the bicycle is designed as an e-bike or as a bicycle without a motor, a down tube and a head tube. The main frame may further include a top tube which is connected to the head tube and the seat tube. According to one embodiment, the main frame of the bicycle frame according to the invention may include a top tube, whereas in another embodiment, the main frame may be designed without a top tube. A rear triangle is also an integral component of the bicycle frame according to the invention. A rear triangle within the meaning of the present invention refers to the seat stays and the chain stays of the bicycle frame.The term "chainstays" encompasses the corresponding structurally load-bearing elements of the bicycle frame, even in bicycles that, for example, include a belt drive. Generally, a fork is also considered a component of a bicycle frame; however, it is not the subject of the present application and is not manufactured using the same tooling as the other components of the bicycle frame.

[0015] The method according to the present invention preferably comprises the one-piece production of the bicycle frame without the use of inserts. Inserts in this sense are understood to be semi-finished components lost in the injection mold, particularly made of thermoplastic or other materials. A particular aspect of the method according to the present invention is that preferably all frame tubes of the main frame are formed as continuous hollow profile sections, closed at least over a partial length, and these are formed according to the invention exclusively by means of movable mold slides. The method according to the invention does not require fluid injection technology and does not require lost cores. The product manufactured according to the method...The bicycle frame produced according to the method comprises frame tubes as hollow profile sections with a defined wall thickness and a defined and preferably smooth-walled inner contour.

[0016] A particular advantage of the method according to the invention is that particularly light and stable bicycle frames with a favorable weight-to-stiffness ratio and defined cross-sections and cavities can be produced by plastic injection molding.

[0017] "At least over a partial length" means, in the context of the present invention, that at least some frame tubes may have openings for the passage of cables, wires or the like, or in the form of battery compartments and / or a battery compartment cover, so that the frame tubes do not have a fully enclosed frame cross-section in the relevant areas.

[0018] The cross-section of the frame tubes can be round, oval, square, or in the shape of any other desired contour.

[0019] The method for manufacturing the bicycle frame according to the invention comprises injection molding of a thermoplastic material, preferably a polyolefin.

[0020] The thermoplastic material can generally be selected from a group of plastics including PA (polyamide), PP (polypropylene), PPA (polyphthalamide), PS (polystyrene), PE (polyethylene), ABS (acrylonitrile butadiene styrene), PC (polycarbonate), POM (polyoxymethylene), PEK (polyetherketone ketone), PEEK (polyetheretherketone), PA6 (polyamide 6), PA6.1 (polyamide 6.1), PA 12 (polyamide 12), HPPA (high-performance recycled polyamide), PARA (polyarylamide), PBT (polybutylene terephthalate), and PK (polyketones).

[0021] The method according to the invention particularly preferably comprises the injection molding of a polyamide, more preferably of polyamide 6 (PA6) or a blend of PA66+PA6I / 6T as the matrix material, wherein the injected thermoplastic material can be filled with short fibers made of a tensile-strength material. For the purposes of this application, short fibers are understood to be fibers with a length greater than 0 mm and less than 50 mm, whereas long fibers are tensile-strength fibers that can have a length greater than 50 mm up to an infinite length. The tensile-strength fibers can comprise carbon fibers, aramid fibers, glass fibers, or basalt fibers.

[0022] The article cavity of the injection molding tool used according to the invention corresponds to a negative of the complete bicycle frame without fork, so that the method according to the invention is particularly suitable for producing bicycle frames from thermoplastic material in series production.

[0023] A preferred variant of the method is characterized in that at least one frame tube is formed by means of at least two forming slides that interact in a functional position within the part cavity of the injection mold. In this way, it is possible to form relatively long frame tubes. Forming a single long cavity of a frame tube using at least two interacting forming slides facilitates the transferability of the forming slides from their functional position to a demolding position. Furthermore, this makes it possible to form frame tubes with an internal cross-section that varies along their length. This can be advantageous, for example, in the area of ​​a seat tube, in order to form a section of the seat tube with a cylindrical internal cross-section.

[0024] As is well known, mold slides without draft angles can only be pulled out of the molded article by applying relatively high forces, so this circumstance limits the length of the cavity to be formed with a uniform internal cross-section.

[0025] Preferably, at least one frame tube is molded with two first and second forming slides cooperating as a first slide pair, wherein the first and second forming slides of the first slide pair, in their functional position within the part cavity of the injection mold, interlock at their ends leading into the functional position in the feed direction or abut each other with a parting contour. Such a parting contour within the meaning of the invention can be a parting plane in which the leading ends of the forming slides abut each other in the functional position. However, a parting contour can also be formed by mutually offset or jagged surfaces.

[0026] In a particularly advantageous embodiment of the method according to the invention, it can be provided that, for example, the first forming slide of the first pair of slides has a contour that facilitates demolding, preferably with draft angles, and that the second forming slide of the first pair of slides has a cylindrical contour. This makes it possible, for example, to produce an inner contour of a seat tube that has a cylindrical inner cross-section at least in an area intended for mounting a seat post, whereas the frame tube designed as a seat tube can open accordingly towards a bottom bracket housing or a motor bearing housing. Accordingly, in the embodiment of the method described above, it can be provided that a seat tube of the bicycle frame is formed with the first pair of slides.In this case, it is advantageous if the first forming slide of the first slide pair is used to mold a bottom bracket housing or a motor bearing housing of the bicycle frame.

[0027] In a preferred and advantageous embodiment of the method according to the invention, at least one frame tube, preferably at least one further frame tube, is molded using two first and second forming slides that cooperate as a second pair of slides. Preferably, a first forming slide of the second pair of slides is held or captured in its functional position by a second forming slide of the second pair of slides, which extends at an angle to the first forming slide, preferably at an end leading into the functional position in the feed direction. The angle between the second forming slide of the second pair of slides and the first forming slide of the second pair of slides is preferably greater than 90° and less than 180°.With this variant of the process, it is possible to mold relatively long article cavities, since the cooperating form slides of the second slide pair stabilize in the functional position.

[0028] For example, it can be provided that the second forming slide of the second pair of slides molds a first short tube section of the bicycle frame in the article cavity, preferably as the head tube of the bicycle frame, that the second forming slide of the second pair of slides is moved into the functional position first, that the first forming slide of the second pair of slides molds a second long tube section of the bicycle frame, preferably as the down tube of the bicycle frame, that the first forming slide of the second pair of slides is moved into the functional position after the second forming slide, and that the first forming slide of the second pair of slides is caught at its end leading in the feed direction by the second forming slide of the second pair of slides.

[0029] In an advantageous and expedient embodiment of the method according to the invention, it can be provided that the first forming slide of the second pair of slides engages positively in the second forming slide of the second slide pass at an end leading in the feed direction, preferably immersing itself in a catch opening of the second forming slide of the second pair of slides.

[0030] In an advantageous embodiment, the method may include forming a down tube of the bicycle frame with at least two profile chambers parallel in the direction of extension, preferably using a double-slide forming die. The double-slide may, for example, comprise a first elongated core that forms a main chamber of the down tube. Parallel to this, a further core may extend, forming a closed second chamber of the down tube.

[0031] In a suitable variant of the process, it can further be provided that at least two form slides interpenetrate each other in a functional position within the part cavity. This "slide-by-slide" concept makes it possible, within a limited installation space of the injection mold, whose dimensions are essentially determined by the dimensions of the main mold that defines the part cavity of the main frame, to mold the part to be formed using a large number of form slides.

[0032] In this variant of the method according to the invention, it is advantageous if the first forming slide of the second pair of slides is moved into its functional position through the first forming slide of the first pair of slides. It is practical and expedient to first move the second forming slide into its functional position and then move the first forming slide of the second pair of slides into its functional position through the first forming slide of the first pair of slides.

[0033] In an advantageous embodiment of the method according to the invention, it can be provided that a rear section of the bicycle frame is formed with seat stays and chain stays, which are essentially injection-molded as solid profiles with guide grooves for cables and / or hoses formed within them. The guide grooves can, for example, also be formed with movable mold components or slides / slide jaws that can be relocated at a corresponding position in the mold.

[0034] The process is preferably characterized in that the thermoplastic material is filled with tensile-strength short fibers, which are preferably selected from a group of fibers comprising carbon fibers, glass fibers, aramid fibers, Kevlar fibers and basalt fibers.

[0035] Preferably, additionally or alternatively, wound, laid and / or woven tensile-strength long fibers are introduced at least in partial areas into the article cavity, which are overmolded with the thermoplastic matrix material, preferably with a polyamide, wherein the tensile-strength long fibers are selected from a group of fibers comprising carbon fibers, glass fibers, aramid fibers, Kevlar fibers and basalt fibers.

[0036] The method according to the invention can include introducing tensile-strength continuous fibers in the form of tapes (UD tape) or in the form of prepregs with a thermoplastic matrix into the injection molding tool before closing the complementary molded parts forming the article cavity.

[0037] The process can further include introducing the fiber reinforcement described above into the part cavity in a load-optimized manner with respect to the bicycle frame to be manufactured. Load-optimized means that the fiber reinforcement is introduced into the tool in such a way that the fibers are aligned in the direction of the main load direction of the bicycle frame to be manufactured.

[0038] A second aspect of the invention relates to an injection mold comprising at least one main mold with an article cavity that corresponds at least to the contour of a main frame of a bicycle and at least one first pair of slides with cooperating first and second form slides, wherein the first and second form slides of the first pair of slides are designed to interlock in a functional position within the article cavity of the injection mold at their ends leading into the functional position in the feed direction or to abut each other with a parting contour.

[0039] A main tool within the meaning of the invention is understood to be that part of the injection molding tool which comprises the essential part of the article cavity.

[0040] The injection molding tool according to the invention is preferably designed to carry out the method described above.

[0041] In an advantageous embodiment of the injection mold according to the invention, it is provided that the mold has at least a second pair of slides for forming the main frame of the bicycle, wherein the second pair of slides comprises at least a first and a second mold slide, which are configured such that the first mold slide is held in the functional position by the second mold slide, which preferably extends at an angle to the first mold slide, preferably at an end leading into the functional position in the feed direction. The first and the second mold slide can extend at an angle of greater than 0° and less than 180° to each other.

[0042] Another aspect of the present application, which is also eligible for protection in itself, relates to a bicycle frame made of a thermoplastic material preferably reinforced with tensile fibers, as a one-piece injection-molded bicycle frame comprising several frame tubes, which are at least partially designed as continuous hollow profiles, closed at least over a partial length and largely smooth-walled on the inside, with a defined wall thickness and a defined profile cross-section, wherein the frame tubes are connected to each other freely and with a uniform material.

[0043] Preferably, the frame tubes have a smooth and uniform inner surface over at least a substantial portion of their length. The surface preferably has a roughness depth corresponding to the surface finish of the part cavity produced by electroresistive machining of the part cavity. The surface finish according to standard VDI 3400 can range from 12 to 45, which corresponds to a surface roughness Ra between 0.4 and 18 µm.

[0044] In a preferred embodiment of the bicycle frame according to the invention, the frame tubes are selected from a group of frame parts comprising a top tube, a down tube, a seat tube, chainstays and seat stays, wherein the bicycle frame has at least one main frame comprising at least one seat tube and a down tube and a bottom bracket housing or motor bearing housing connecting these in one piece and a one-piece molded rear triangle, and the rear triangle of the bicycle frame is designed with seat stays and chainstays which are essentially injection-molded as solid profiles with guide grooves formed in them for cables and / or hoses.

[0045] The bicycle frame according to the invention is preferably designed as a bicycle frame for an electric bicycle. In one variant, this frame can be designed with a top tube connecting the seat tube and the head tube. The top tube can have an open hollow profile cross-section over at least a portion of its length, for example as a U-profile open downwards towards the bottom bracket housing or motor bearing housing, which can also be formed, for example, during the manufacture of the bicycle frame using a corresponding slide.

[0046] In one embodiment of the bicycle frame according to the invention, it is designed entirely without a top tube.

[0047] The down tube of the bicycle frame according to the invention is preferably designed with a battery compartment for receiving an electric battery or accumulator. For this purpose, the down tube of the bicycle frame can be provided with a first hollow profile section that is completely closed, and a second hollow profile section that is not completely closed, for example, a U-profile, which forms a battery compartment and can be closed with a battery compartment cover. It should be noted here that the terms accumulator and battery are used synonymously within the scope of this application.

[0048] The bicycle frame according to the invention is preferably manufactured according to the method described above.

[0049] The invention is explained below with reference to and based on an exemplary embodiment shown in the drawings.

[0050] They show:

[0051] Figure 1 shows a schematic view of a first variant of the main tool of an injection molding tool according to the invention,

[0052] Figure 2 shows a schematic view of the arrangement of the moving parts of the injection mold without the main mold.

[0053] Figure 3 shows a schematic view of the injection mold according to the invention, including the movable mold parts.

[0054] Figure 4 shows an enlarged view of the second pair of sliders in the functional position,

[0055] Figure 5 shows a schematic perspective representation of a first variant of a bicycle frame according to the invention and

[0056] Figure 6 shows a schematic representation of a second variant of a main tool for manufacturing a second variant of the bicycle frame according to the invention. The method according to the invention comprises manufacturing a bicycle frame 210 from a fiber-reinforced, injection-molded thermoplastic using an injection mold 100 with a plurality of movable mold parts. The method is explained below essentially with reference to the injection mold 100 shown in the drawings.

[0057] The injection mold 100 comprises a base mold 110, which forms the majority of an article cavity 111. The base mold 110 can, for example, comprise at least two mold halves, which define the negative of the article to be molded, in this case the bicycle frame 210.

[0058] Figure 1 shows a schematic view of the main tool 110 with the part cavity 111 and without the movable mold parts. The part cavity 111 shown in Figure 1 forms a main frame and the rear triangle 211 of the bicycle frame 210 according to a first embodiment. The bicycle frame 210 according to an embodiment is shown in perspective in Figure 5. The bicycle frame 210 is designed as a mountain bike frame for an electric bicycle.

[0059] The main frame comprises a seat tube 212, a top tube 213 extending between the seat tube 212 and a head tube 214, and a down tube 215 connected to a motor mount housing 216. The down tube 215 is designed to accommodate a battery, which is inserted from below through the motor mount housing 216 into the frame profile of the down tube 215.

[0060] The motor bearing housing 216 is connected in one piece to a lower part of the head tube 214, the down tube 215, and the chainstays 217 of the rear triangle 211. The rear triangle 211 of the bicycle frame 210 also includes seat stays 218, which are designed as injection-molded solid profiles and have integrated cable guides 219 in the form of grooves on their underside facing away from the user of the bicycle frame 210.

[0061] The seat tube 212, the down tube 215, and the head tube 214 are each designed as continuous hollow profiles, with the down tube 215, in the embodiment according to Figure 5, comprising a fully enclosed profile cross-section with a first profile chamber 220 and a second profile chamber 221 extending parallel to it. The first profile chamber 220 is designed to accommodate a battery.

[0062] As can be readily seen from the perspective view in Figure 5, the down tube 215 has a downwardly open, U-shaped profile cross-section over a portion of its length. The bicycle frame 210 according to the invention is manufactured entirely in one piece from an injection-molded thermoplastic material in an injection mold 100, to which reference is made below. The following description of the manufacturing process is given sequentially with reference to individual frame tubes of the first variant of the bicycle frame 210 according to the invention, beginning with the main frame.

[0063] The seat tube 212 of the bicycle frame 210 and the motor mount housing 216 are injection-molded as continuous hollow profiles, the inner cross-section of which is molded via a first pair of slides. The first pair of slides comprises a first forming slide 121, which defines the inner contour of the motor mount housing 216 and the lower part of the seat tube 212 adjacent to the motor mount housing 16.

[0064] Figure 2 shows the first forming slide 121 and the second forming slide 122 in their functional position, in which they collide at a parting contour 123. The parting contour 123 is formed by stepped end faces of the leading ends of the first and second forming slides 121 and 122, respectively, which interlock in their functional position. The first lower forming slide 121 is designed to facilitate demolding with draft angles and is conical in the area of ​​a section leading in the feed direction, whereas the contour of the second upper forming slide 122 is cylindrical and consequently defines a cylindrical inner cross-section of the seat tube 212 in its upper region.

[0065] The U-shaped cross-section of the top tube 213 is formed using a top tube slide 160.

[0066] The head tube 214 and the down tube 215 are formed using a second pair of slides, which, as can be seen particularly in the enlarged view in Figure 4, interlock positively in their functional position. The second pair of slides comprises a first forming slide 131 and a second forming slide 132, wherein the first forming slide 131 is held in its functional position at its end by the second forming slide 132.

[0067] In order to ensure a compact arrangement of all movable mold parts and an interaction of these mold parts for the purpose of forming the injection-molded article, the first mold slide 121 of the first slide pair and the first mold slide 131 of the second slide pair are designed such that the first mold slide 131 of the second slide pair passes through or penetrates the first mold slide 121 of the first slide pair and can be moved through the first mold slide 121 of the first slide pair into its functional position, in which it interacts with the second mold slide 132 of the second slide pair.

[0068] In the method according to the invention, the second forming slide 132 of the second pair of slides is first moved into its functional position, then the first forming slide 131 of the second pair of slides is advanced through the first forming slide 121 of the first pair of slides into its functional position, where it engages in a window-like recess 133 of the second forming slide 132 in a form-fitting manner.

[0069] As can be seen in particular from the enlarged illustration in Figure 4, the first forming slide 131 of the second pair of slides is designed as a double slide with two forming cores extending parallel and at a distance from each other, with which the first and second profile chambers 220, 221 of the lower tube 215 are formed.

[0070] To form a steering bearing seat, a steering bearing slide 180 is further provided, which can be designed in such a way that it can center the second forming slide 132 of the second slide pair 130 in the functional position.

[0071] Finally, a rear triangle slider 170 is provided for the formation of the rear triangle 211 of the bicycle frame 210, 220, which forms a partial contour of the chainstays 217 and the seatstays 218 on each side.

[0072] The groove-shaped cable guides 219 are each formed by forming jaws 190 that can be displaced transversely to the chainstays 218, of which only one is visible in the illustration. A corresponding cable guide 219 is formed in each of the chainstays 218. Figure 6 shows a variant of the main tool 110, which is configured for forming a bicycle frame 210 according to a second embodiment. This variant of the main tool 110 is configured to mold a bicycle frame 210 without a top tube and with a down tube 215 that is open at the top. In this variant of the bicycle frame according to the invention, a battery compartment cover is provided on a user-facing side of the down tube 215.

[0073] Reference numeral list Injection mold Main mold Part cavity First mold slide of the first slide pair Second mold slide of the first slide pair Parting contour First slide of the second slide pair Second mold slide of the second slide pair Window-like recess First core Second core Top tube slide Rear triangle slide Headset slide Displaceable mold jaws Bicycle frame Rear triangle Seat tube Top tube Head tube Down tube Motor mount housing Chainstays Seat stays Cable guides 220 First profile chamber

[0074] 221 second profile chamber

Claims

Claims 1. Method for manufacturing a bicycle frame (210) from a thermoplastic material preferably reinforced with tensile fibers, wherein the method comprises injection molding the bicycle frame (210) as a one-piece molded part in a multi-part injection mold (100) and forming at least some of the frame tubes, preferably at least all frame tubes of the main frame as continuous hollow profile sections closed at least over a partial length using a plurality of movable mold parts of the injection mold (100), in particular using a plurality of movable mold slides which are movable from a demolding position to a functional position within a part cavity (111) of the injection mold (100) and from the functional position to the demolding position.

2. Method according to claim 1, characterized in that at least one frame tube is formed by means of at least two forming slides cooperating in a functional position in the article cavity (111) of the injection molding tool (100).

3. Method according to one of claims 1 or 2, characterized in that at least one frame tube is molded with two first and second forming slides (121, 122) cooperating as a first slide pair, wherein the first and second forming slides (121, 122) of the first slide pair interlock at their ends leading into the functional position in the feed direction within the article cavity (111) of the injection molding tool (100) or bear against each other with a parting contour (123).

4. Method according to claim 3, characterized in that the first forming slide (121) of the first pair of slides has a demolding-favorable contour, preferably with demolding slopes, and that the second forming slide (122) of the first pair of slides has a cylindrical contour.

5. Method according to one of claims 3 or 4, characterized in that a seat tube (212) of the bicycle frame (210) is molded with the first pair of sliders.

6. Method according to one of claims 3 to 5, characterized in that a bottom bracket housing or a motor bearing housing (216) of the bicycle frame (210) is molded using the first forming slide (121) of the first pair of slides.

7. Method according to one of claims 1 to 3, characterized in that at least one frame tube is molded with two first and second forming slides (131, 132) cooperating as a second slide pair, wherein a first forming slide (131) of the second slide pair is angled at an angle to the The first form slide (131) extending to the form slide (132) of the second pair of slides is held in the functional position, preferably at an end leading into the functional position in the feed direction.

8. Method according to claim 7, characterized in that the second forming slide (132) of the second pair of slides forms a first short tube section of the bicycle frame (210) in the article cavity (111), preferably as the head tube (214) of the bicycle frame (210), that the second forming slide (132) of the second pair of slides is moved into the functional position first, that the first forming slide (131) of the second pair of slides forms a second long tube section of the bicycle frame (211), preferably as the down tube (215) of the bicycle frame (210), that the first forming slide (131) of the second pair of slides is advanced into the functional position after the second forming slide (132), and that the first forming slide (131) of the second pair of slides at its feed-directed end from the second form slide (132) of the second pair of valves is captured.

9. Method according to one of claims 7 or 8, characterized in that the first forming slide (131) of the second pair of slides engages in the functional position at an end leading in the feed direction in a form-fitting manner into the second forming slide (132) of the second pair of slides, preferably immersing itself in a catch opening of the first forming slide of the second pair of slides.

10. Method according to one of claims 7 to 9, characterized in that a down tube (215) of the bicycle frame (210) has at least two sections arranged in The extension direction is formed by parallel profile chambers (220,221) using a first forming slide (131) of the second slide pair designed as a double slide.

11. Method according to any one of claims 1 to 10, characterized in that at least two form slides (121, 131) are in a functional position within the penetrate the article cavity.

12. Method according to claim 11, characterized in that the first forming slide (131) of the second pair of slides is moved into the functional position through the first forming slide (121) of the first pair of slides.

13. Method according to one of claims 1 to 12, characterized in that a rear structure (211) of the bicycle frame (211) is formed with seat stays (218) and chain stays (217) which are essentially injection molded as solid profiles with guide grooves formed in them for cables and / or lines.

14. Method according to any one of claims 1 to 13, characterized in that the thermoplastic polymer is filled with tensile-strength short fibers, which are preferably selected from a group of fibers comprising carbon fibers, glass fibers, aramid fibers, Kevlar fibers and basalt fibers.

15. Method according to one of claims 1 to 14, characterized in that wound, laid and / or woven tensile-strength long fibers are introduced at least in partial areas into the article cavity (111), which is lined with a thermoplastic matrix material, preferably overmolded with a polyamide, wherein the tensile long fibers are selected from a group of fibers comprising carbon fibers, glass fibers, aramid fibers, Kevlar fibers and basalt fibers.

16. Injection mold (100) preferably for carrying out the method according to one of claims 1 to 15, comprising at least one main mold (110) with at least one part cavity (111) which corresponds at least to the contour of a main frame of a bicycle and at least one first pair of slides with cooperating first and second form slides (121, 122) wherein the first and second form slides (121, 122) of the first pair of slides are configured to interlock in a functional position within the part cavity (111) of the injection mold (100) at their ends leading in the feed direction into the functional position or to bear against each other with a parting contour (123).

17. Injection mold (100) according to claim 16 with at least one second pair of slides for forming the main frame of the bicycle, comprising at least one first and one second mold slide (131, 132) which are designed such that the first mold slide (131) is held in the functional position, preferably at an end leading into the functional position in the feed direction, by the second mold slide (132) which preferably extends at an angle to the first mold slide.

18. Bicycle frame made of a thermoplastic material, preferably reinforced with tensile fibers, as a one-piece injection-molded bicycle frame (210) which is preferably manufactured according to the method with the features of one of claims 1 to 15, comprising several frame tubes which are at least partially designed as continuous hollow profiles, closed at least over a partial length and largely smooth-walled on the inside, with a defined wall thickness and a defined profile cross-section, wherein the frame tubes are connected to each other without fasteners and with a uniform material.

19. Bicycle frame according to claim 18 characterized in that the frame tubes are selected from a group of frame parts comprising a top tube (213), a down tube (215), a seat tube (212), chainstays (217) and seat stays (218), wherein the bicycle frame (210) has at least one main frame comprising at least one seat tube (212) and a down tube (215) and a bottom bracket housing or motor bearing housing (216) connecting these in one piece and a one-piece molded rear triangle (211), the rear triangle (211) of the bicycle frame being designed with seat stays (218) and chainstays (218) which are essentially injection molded as solid profiles with guide grooves (219) formed in them for cables and / or hoses.

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