Modular bicycle frame and modular series for geometrically similar bicycle frames

Abstract

The invention relates to a modular bicycle frame 1, comprising a plurality of frame elements 4, 7, 8, 9, 10, 30, 31, 32, 33, 34, 35, 64, 65, 66, 67, 68, 69 and housing regions 3, 6, T, wherein frame elements 4, 7, 8 of a first category are provided which at least each have one connection end 12, 13, 14, 15, 16, 17. A connection end 12, 13, 14, 15, 16, 17 of at least one first frame element 4, 7, 8 and at least one connection end 12, 13, 14, 15, 16, 17 of a second frame element 4, 7, 8 are, in the connected state, arranged flush to one another, and these connection ends 12, 13, 14, 15, 16, 17 of the frame elements 4, 7, 8 each have at least one connection contour C1, C2, C3, C4, C5, C6, preferably a form-fit contour, with the proviso that at least one frame element of a second category is provided which is designed as a coupling element 30, 31, 32, 33, 34, 35, 64, 65, 66, 67, 68, 69, wherein the coupling element 30, 31, 32, 33, 34, 35, 64, 65, 66, 67, 68, 69 in turn has at least one connection contour E1, E2, E3, E4, preferably a form-fit contour, which connection contour E1, E2, E3, E4 is designed in some regions to be complementary to the connection contour C1, C2, C3, C4, C5, C6 of the connection end 12, 13, 14, 15, 16, 17 of the first frame element 4, 7, 8 and in some regions to be complementary to the connection contour C1, C2, C3, C4, C5, C6 of the connection end 12, 13, 14, 15, 16, 17 of the second frame element 4, 7, 8.

Description

[0001] Modular bicycle frame and modular series for geometrically similar bicycle frames

[0002] The invention relates to a modular bicycle frame comprising a plurality of frame elements and housing areas, wherein frame elements of a first category are provided, each having at least one connecting end. Furthermore, a modular series for geometrically similar bicycle frames based on the present bicycle frame concept is proposed.

[0003] Bicycle frames are known which are made up of modular frame elements such as tubular elements and coupling elements. The coupling elements, such as sleeves, are provided at nodes in order to indirectly connect the connecting ends of the frame elements to one another. The tubular elements and coupling elements of such bicycle frames are made of metal or plastic. They are joined together using a suitable joining method such as soldering, welding or gluing. In addition, a bicycle frame is known, for example from the publication DE 74 32 809 U, preferably from a fibre-reinforced plastic which is produced using a large forming tool, for example in a monocoque design with a frame element which is made up of half-shell parts. Production in a large forming tool is very complex. This method has an impact, for example, on the...This is disadvantageous when bicycle frames are to be manufactured in different sizes. Several large forming tools result in high costs. In this case, bicycle frames made from frame elements that can be assembled have an advantage.

[0004] A modular bicycle frame is known, for example, from DE 694 18 046 T2. It is made from a thermoplastic material and comprises frame elements (profiles) and so-called connecting housings. The frame elements have connecting ends provided with tenons. The tenons are inserted into the connecting housings. According to this prior art, the assembly and connection of a frame element to the connecting housing is supposed to be ensured by thermal shrinkage of the thermoplastic after shaping during cooling. The production of this known modular bicycle frame is considered to be very complex and rather inflexible.

[0005] The invention is based on the object of proposing a modular bicycle frame which comprises a plurality of frame elements and housing areas which can be connected more easily, whereby the production of a modular series of geometrically similar bicycle frames should be promoted as far as possible.

[0006] According to the invention, the object is achieved in that a connecting end of at least one first frame element and at least one connecting end of a second frame element are arranged in alignment with one another in the connected state, and wherein these connecting ends of the frame elements each have at least one connecting contour, preferably a form-fitting contour, with the proviso that at least one frame element of a second category is provided, which is designed as a coupling element, wherein the coupling element in turn has a connecting contour, preferably as a form-fitting contour, which connecting contour is designed in some areas to be complementary to the connecting contour of the connecting end of the first frame element and in some areas to be complementary to the connecting contour of the connecting end of the second frame element.

[0007] The indexing of the frame elements as "first and second" is always to be understood in a general way; it refers to the spatial-physical relationship of any (first) frame element that is to be connected or is connected to another (second) frame element. The term "aligned" in the sense of the invention means that the connecting ends of two frame elements are abutted against one another or at least arranged close to one another in the abutting direction and are positioned without any significant lateral offset from one another and without any significant angular offset from one another.

[0008] The proposed measure enables two frame elements to be connected without the otherwise conventional joining methods such as soldering, welding or gluing. In principle, an adhesive can also be used, but this is unnecessary for the load-bearing components of the main connection. However, an adhesive can expediently be provided as a securing means to prevent the connection from becoming unintentionally loose, as will be explained below. The connecting contours can in principle be designed as frictional locking contours. However, they are preferably provided as form-locking contours or essentially interact with one another in a form-locking manner, wherein the form-locking effect can be supplemented by a frictional locking effect.

[0009] To assemble two frame elements, their connecting ends are placed against one another in alignment as described above. Both connecting ends have essentially the same cross-section. A form-fitting contour is expediently provided on the outside of each connecting end. To connect the two frame elements, the coupling element, which in turn has a form-fitting contour, is brought into contact with the two adjacent form-fitting contours of the frame elements to be connected. For this purpose, the coupling element is provided with a form-fitting contour which is partially complementary to the form-fitting contour of the first frame element and partially complementary to the form-fitting contour of the second frame element.In this way, the coupling element overlaps the connecting ends of the two frame elements to be connected and thus establishes the mechanical connection between these two frame elements.

[0010] The first frame element is conveniently provided with a top tube element and a steering head housing area.

[0011] The upper frame element and the control head housing area can be combined to form an integrated upper frame element.

[0012] The second frame element is simply provided with a down tube element and a pedal drive housing area.

[0013] It is particularly useful when the down tube element and the pedal drive housing area are combined to form an integrated subframe element.

[0014] The integrated frame elements, such as the upper frame element and the lower frame element, have a reduced component size, which allows the corresponding frame element to be manufactured using a relatively small tool, for example in a primary forming process such as casting or injection molding. The integrated design of the frame element also facilitates production using a 3D

[0015] Printing process. The reduced component size allows the integrated frame element to be produced using a relatively small 3D printer. Such smaller 3D printing devices are available in greater numbers and are cheaper to purchase and operate than large devices that would be suitable for 3D printing a complete bicycle frame. The proposed measure reduces the component size to a reasonable level. Geometry-dependent cost components that arise during the production of the bicycle frame can thus be reduced.

[0016] A third frame element of the first category can be designed as a seat post frame element.

[0017] Of the following frame elements: upper frame element, lower frame element and seat post frame element, at least one frame element is advantageously provided with two connecting ends each, wherein the two connecting ends each have at least one connecting contour, preferably at least one connecting contour is designed as a form-fitting contour.

[0018] At each connecting end, two form-locking contours can be arranged symmetrically on opposite sides, left and right. In relation to the bicycle frame, the form-locking contours are conveniently arranged on the left and right sides of the bicycle frame, respectively.

[0019] For the stability of the bicycle frame, it is useful if the form-fitting contours provided at the connecting ends of the frame elements are provided with toothed elements.

[0020] Two coupling elements can be arranged symmetrically, whereby each coupling element is advantageously provided with a form-fitting contour.

[0021] Preferably, the form-fitting contours of the frame elements are provided with toothed elements. Likewise, the form-fitting contour of each coupling element can be provided with toothed elements. The toothed elements of two frame elements to be connected are complementary to the toothed elements of a coupling element. In the assembled state, the coupling element overlaps the frame elements to be connected, so that the complementary toothed elements are in positive engagement.

[0022] Toothing elements with wedge-shaped cross-sections and interspaced teeth are advantageous. The wedge shape of the teeth offers the significant advantage that the positive connection can be supplemented with a non-positive connection component achieved by wedging.

[0023] The toothing elements of the frame elements can each have at least one longitudinal tooth and at least one transverse tooth, with the transverse tooth preferably crossing the longitudinal tooth orthogonally. Advantageously, two transverse teeth are assigned to the longitudinal tooth in a double-cross pattern and the longitudinal tooth preferably extends parallel to a longitudinal direction of the frame element. During operation, a bicycle frame must withstand tensile and compressive stress, bending and torsion. The arrangement of the teeth in a longitudinal direction and a transverse direction so that they cross each other enables complex forces to be absorbed in the area of ​​a connection between two frame elements. In the case of those toothing elements which are arranged on the coupling element, these can be tooth gaps. The tooth gaps are arranged crosswise in the same double-cross pattern as the teeth on the frame elements.This enables the coupling element, or rather its tooth gaps, to engage with the longitudinal tooth and transverse tooth of the frame element. The position of the connected frame elements relative to one another is thus secured.

[0024] Alternatively, the toothing elements provided on the coupling element can each have at least one longitudinal tooth and at least one transverse tooth. In this case, the appropriate tooth gaps are provided on the frame elements. The position of the connected frame elements relative to one another is also secured in this way.

[0025] The toothing elements proposed here differ from the toothing of a transmission, such as gears or racks, which have to perform a movement, which is why their tooth flanks are designed as surfaces on which a rolling movement has to take place. The toothing elements according to the invention, on the other hand, have tooth flanks that are intended to fulfil a fastening function. For this purpose, at least some of the tooth flanks are wedged together. The tooth flanks are advantageously prepared for this purpose so that they can nestle against one another over a flat surface and form a frictional connection. In this way, in addition to the positive connection between the toothing elements involved, a non-positive component is added, which provides a strong connection between two frame elements and a coupling element, or a pair of coupling elements.

[0026] Advantageously, a means for generating a preload between the coupling element and the associated frame elements is provided. The means for generating a preload can be used to preload the connecting contours, or the connecting contours designed as form-fitting contours. This is particularly helpful when the form-fitting contours are provided with toothed elements that can achieve a force-fitting component for connecting the associated frame elements by wedging the toothed elements.

[0027] The means for generating the preload can comprise at least one screw, by means of which the coupling element can be preloaded against the participating frame elements. Alternatively, a type of tensioning element can be provided, which is arranged through the coupling element or around it in such a way that the participating frame elements can be tensioned together. As a surrounding tensioning element, it can be designed in the manner of a tensioning clamp, pipe clamp, or tensioning belt.

[0028] The connecting ends of the frame elements can each be provided with at least one hole, for example a blind hole, for screwing in the screw. Preferably, the coupling element is provided with at least two through-openings for screws, i.e., with one through-opening for connection to a first frame element and a second through-opening for connection to a second frame element.

[0029] The subframe element is conveniently provided with a swing arm bearing housing area, which serves to support a rear swing arm.

[0030] At least one frame element of a third category may be provided, namely a rear frame element that serves as a rear swing arm. Preferably, two rear frame elements are provided, namely a left rear frame element and a right rear frame element, which are firmly connected to one another and form a rear swing arm. Advantageously, each rear swing arm is mounted on the swing arm bearing housing area.

[0031] For the purpose of mounting a damper element, a support element for the rear swing arm can preferably be arranged on the lower frame element. Furthermore, the support element can be arranged, for example, on the upper frame element.

[0032] Alternatively, for a bicycle frame designed without a sprung rear swing arm (hardtail), a rear frame element can be provided which has at least one connecting end. The rear frame element can be connectable to a modified subframe element and / or a modified seat tube frame element, which in turn is then provided with an additional connecting end for connection to the rear frame element. For the additional connection, an additional rear frame coupling element or a pair of rear frame coupling elements is advantageously provided. Furthermore, the proposed principle, which reduces the component size of frame elements to a reasonable level in order to reduce geometry-dependent cost components, can also be used to produce a bicycle frame which has a different frame shape.For example, a frame shape, or suitable frame elements, can be designed in such a way that a tandem, cargo bike, recumbent bike or a frame shape for a multi-track bicycle, such as a tricycle or a four-wheeled bicycle, can be put together.

[0033] The pedal drive housing area of ​​the subframe element is advantageously designed to accommodate a support motor unit, which is simply provided with a pedal crank. Standard motor-gearbox units with an electric motor can be provided as the support motor unit.

[0034] The subframe element can have a means for receiving an energy storage device, preferably an accumulator for electrical energy. At least one frame element and / or one housing region is expediently made of a plastic selected from the following group of plastics: polyamide, polyacetal / polyoxymethylene, polyethylene, polypropylene, polycarbonate, polyvinyl chloride, polytetrafluoroethylene, acrylonitrile butadiene styrene, polyketone, polyether ketone, polyether ether ketone, polysulfone, polybutylene terephthalate, polyphthalamide, polyphenylene sulfide, polyphenyl sulfone, thermoplastic polyurethane, thermoplastic elastomer.

[0035] The plastic may contain at least one filler in the form of reinforcing particles and / or reinforcing fibers (compound).

[0036] The frame element is preferably manufactured using the injection molding process.

[0037] Furthermore, a modular series for geometrically similar bicycle frames according to the invention is proposed. The modular series comprises frame elements of the first category, which are designed as identical parts, and comprises frame elements of the second category, which are designed as modular parts. The modular parts can be provided in different sizes in order to be able to be joined together with the identical parts to form bicycle frames of different frame sizes. Advantageously, a set of modular parts is put together in each case, which includes all the modular parts required for a specific frame size.

[0038] The modular series can include modular components of the second category in the form of a series of coupling elements with staggered sizes. The design can also be adapted in detail to ensure compatibility with the identical components.

[0039] The module parts of the second category suitably comprise a series of spacer elements with a stepped size or comprise coupling elements with integrated spacer elements which have a stepped size.

[0040] The invention is illustrated below by way of example in a drawing and described in detail with reference to several figures. They show:

[0041] Fig. 1 is a perspective view of the essential components of a first embodiment of the bicycle frame according to the invention,

[0042] Fig. 2 is a perspective view of the right steering head coupling element of the bicycle frame according to Fig. 1,

[0043] Fig. 3 is a side view of the control head coupling element according to Fig. 2,

[0044] Fig. 4 is a perspective view of a right seat tube coupling element of the bicycle frame according to Fig. 1,

[0045] Fig. 5 is a side view of the seat tube coupling element according to Fig. 4,

[0046] Fig. 6 is a perspective view of the essential components of a second embodiment of the bicycle frame according to the invention,

[0047] Fig. 7 is a cross-sectional view of the rear upward connecting end of the subframe element and the downward connecting end of the seat post frame element according to Fig. 6 in the connected state,

[0048] Fig. 8 is a perspective view of the right steering head coupling element of the bicycle frame according to Fig. 6,

[0049] Fig. 9 is a side view of the right steering head coupling element according to Fig. 8,

[0050] Fig. 10 . a side view of the bicycle frame according to Fig. 1 in the assembled state,

[0051] Fig. 11 is a side view of the bicycle frame according to Fig. 6 in the assembled state.

[0052] Fig. 1 shows a first embodiment of the bicycle frame 1 according to the invention. This example is a bicycle frame with a sprung rear swing arm (softtail).

[0053] The bicycle frame 1 has five frame elements that are designed as identical parts. Identical parts, within the meaning of the invention, are those frame elements that can be used to produce a larger bicycle frame than the one shown in Fig. 1. An example of a larger bicycle frame is shown in Fig. 6, which includes the five identical parts.

[0054] A first identical part Gl is a first frame element which combines a top tube element 2 and a steering head housing area 3 to form an upper frame element 4. The upper frame element 4 forms the first identical part Gl. A second identical part G2 is a second frame element which combines a down tube element 5 and a pedal drive housing area 6 to form a lower frame element 7. The lower frame element forms the second identical part G2. A third frame element which is designed as a seat post frame element 8 is provided as the third identical part G3. The first three identical parts Gl, G2 and G3 form frame elements of a first category. The first category means that each of the three frame elements (4, 7, 8) has at least one connecting end. In the present example, all three frame elements of the first category are each provided with two connecting ends.

[0055] The fourth identical part G4 and the fifth identical part G5 form frame elements of a third category. The third category includes frame elements that do not have any connecting ends. The fourth identical part G4 is a frame element that forms a left rear frame element 9, and the fifth identical part G5 is a frame element that forms a right rear frame element 10. The two rear frame elements 9 and 10 are firmly connected to one another in the fully assembled state and form a rear swing arm 11 as already mentioned above.

[0056] The subframe element 7 further comprises a swing arm bearing housing area T for the rear swing arm 11.

[0057] The upper frame element 4 as the first identical part 11 has a front connecting end 12 and a rear connecting end 13. The front connecting end 12 of the upper frame element 4 is provided below its top tube element 2 and arranged such that it is rooted at the steering head housing area 3. The front connecting end 12 has partial contact with the top tube element 2 and another part of the connecting end 12 bends freely downwards, away from the top tube element 2. The rear connecting end 13 of the upper frame element 4 extends in a longitudinal direction L of the top tube element 2.

[0058] The subframe element 7, as the second identical part G2, in turn has a front connecting end 14 and a rear connecting end 15. The front connecting end 14 extends in a longitudinal direction D of the down tube element 5. The rear connecting end 15 of the subframe element 7 extends upwards from the pedal drive housing area 6 toward the position of a seat post (not shown), or to the seat post frame element 8.

[0059] The seat post frame element 8 as the third identical part G3 has an upper connecting end 16 and a lower connecting end 17.

[0060] At the front of the bicycle frame 1, the front connecting end 12 of the upper frame element 4 is provided for connection to the front connecting end 14 of the lower frame element 7.

[0061] In addition, the rear connecting end 13 of the upper frame element 4 is provided for connection to the upper connecting end 16 of the seat post frame element 8. Furthermore, the lower connecting end 17 of the seat post frame element 8 is provided for connection to the rear connecting end 15 of the lower frame element 7.

[0062] In this way, six connecting ends can be joined together in pairs to form three load-bearing main connections of the proposed bicycle frame 1. In order to provide three strong main connections for the proposed bicycle frame 1, the connecting ends of the frame elements involved are each provided with a connecting contour on both the left side of the bicycle frame and the right side of the bicycle frame, which in the present example is designed as a form-fitting contour.

[0063] A front main connection H1 connects the upper frame element 4 to the lower frame element 7. Using the left side of the bicycle frame 1, the functional principle is explained below using the left symmetry side of this front main connection H1 between the upper frame element 4 and the lower frame element 7. The right side of this front main connection H1 functions in a mirror image according to the same principle. The remaining two main connections also function according to the same functional principle.

[0064] The functional principle uses positive-locking toothing elements for the connecting contours. The upper frame element 4 is provided with connecting contours 01 and 02. The lower frame element 7 has connecting contours 03 and 04, and the seat post frame element 8 is provided with connecting contours 05 and 06. All connecting contours (01-06) are preferably designed as positive-locking contours.

[0065] On the left side of the front connecting end 14 of the subframe element 7, a positive-locking contour is provided, which is equipped with toothing elements 19. The toothing elements 19 have teeth 20 with a wedge-shaped cross-section and intervening tooth gaps 21.

[0066] The toothing elements 19 have a longitudinal tooth 22 and two transverse teeth 23 and 24. In the present example, the longitudinal tooth 22 is aligned parallel to the longitudinal direction D of the subframe element 7. The two transverse teeth 23 and 24 cross the longitudinal tooth 22 orthogonally. This results in a double-cross-like shape of the longitudinal and transverse teeth of these toothing elements 19 on the left side of the front connecting end 14 of the subframe element 7.

[0067] The front connecting end 12 of the upper frame element 4 has a connecting contour 03 which has a kinked region 25 which is set flush against the front connecting end 14 of the lower frame element 7; the two opposing connecting ends 12 and 14 are in contact with one another in the present example. The left side of the front connecting end 12 of the upper frame element 4 also has toothing elements which comprise a longitudinal tooth 27 and two transverse teeth 28 and 29. The longitudinal tooth 27 provided on the upper frame element 4 has a kink. The transverse tooth 28 is on that part of the connecting end 12 which is rooted on the steering head housing region 3. The other transverse tooth 29 is located on that bent area 25 of the connecting end 12, which is why the two transverse teeth 28 and 29 are not parallel to each other, but orthogonal to the respective section of the bent longitudinal tooth 27, i.e.arranged orthogonally in front of the bend or behind the bend.

[0068] In order to be able to connect two toothing elements of the frame elements involved, each arranged on the left and two on the right side of the bicycle frame 1, the coupling elements are preferably provided in pairs, i.e. a left coupling element and a mirror-image right coupling element. In the example in Fig. 1, in order to connect the upper frame element 4 to the lower frame element 7, which takes place in the steering head housing area 3, a pair of coupling elements is provided, which are referred to here as a pair of steering head coupling elements 30 and 31. The steering head coupling element 31 has a connecting contour E1 and the steering head coupling element 30 is provided with a mirror-image connecting contour.

[0069] In addition, a pair of seat tube coupling elements 32 and 33 are provided for connecting the rear upward connecting end 15 of the subframe element 7 to the downward connecting end 17 of the seat post frame element 8. The seat tube coupling elements 32 and 33 each have a connecting contour E2 and E3, respectively.

[0070] Furthermore, in this sense, a pair of upper frame

[0071] Coupling elements 34 and 35 are provided, which serve to connect the rear connecting end 13 of the upper frame element 4 to the forward-facing upper connecting end 16 of the seat post frame element 8. The upper frame coupling element 35 has a connecting contour E4 and the upper frame coupling element 34 is provided with a mirror-image connecting contour.

[0072] In the foreground of Fig. 1, left-side toothing elements 36 at the front of the upper frame element 4 and the left-side toothing elements 19 of the lower frame element 7 can be seen. Both left-side toothing elements 19 and 36 can be connected by means of the left steering head coupling element 30.

[0073] The right steering head coupling element 31, in turn, has toothing elements 38. The inside of the right steering head coupling element 31 is visible in Fig. 1 and shown enlarged in Fig. 2. Corresponding mirror-image toothing elements are provided on the right side at the connecting ends 12 and 14 of the upper frame element 4 and the lower frame element 7.

[0074] 2, the tooth gaps of the right-hand control head coupling element 31 are clearly arranged in a double cross-like manner, i.e. a longitudinal tooth gap 39 is crossed by two transverse tooth gaps 40 and 41 respectively. The spatial-physical design of the tooth gaps (39, 40, 41) is complementary to the spatial-physical design of the longitudinal tooth and the two transverse teeth which are provided on the right-hand side at the front connecting end 12 of the upper frame element 4 and the front connecting end 14 of the lower frame element 7. The latter are arranged in mirror image to the longitudinal tooth 22 and the transverse teeth 23 and 24 which are provided on the left-hand side of the connecting ends 12 and 14 of the upper frame element 4 and the lower frame element 7. Fig.2 further shows that the transverse tooth gap at the front connecting end 12 of the upper frame element 4, which faces the control head housing area 3, is arranged at the very end of the longitudinal tooth gap 39, whereby a T-shaped design of the tooth gaps 39 / 40 results in this area of ​​the "double cross".

[0075] The double-cross-like arrangement of the tooth gaps forms intersection points Kl and K2 between the longitudinal tooth gap 39 and the transverse tooth gaps 40 and 41. At the intersection point Kl and K2, respectively, there is a through-opening provided for a screw thread. On an outer surface 42 of the right-hand control head coupling element 31 opposite the toothing elements 38, the through-openings are provided with countersinks, preferably each with a conical countersink 43 (countersunk head) for receiving the head of countersunk screws. Corresponding countersunk holes 44 can be seen on the mirror-image left-hand control head coupling element 30.

[0076] The connecting ends 12 and 14 of the upper frame element 4 and the lower frame element 7 are provided on the left side with screw holes 45, 46, 47, and 48 for the countersunk head screws, and on the right side with symmetrically arranged screw holes. This allows the two symmetrical control head coupling elements (30, 31), or their corresponding toothing elements, to be elastically clamped.

[0077] According to Fig. 1, the countersunk head screws serve as means M1 for generating a preload which presses the steering head coupling element 30 against the connecting ends 12 and 14 of the upper frame element 4 and the lower frame element 7. The toothing elements 38 of the right steering head coupling element 31 are pressed opposite one another in the same way by a means M1 (countersunk head screws) against the toothing elements of the upper frame element 4 and the lower frame element 7. For the seat tube coupling elements 32 and 33, countersunk head screws are provided as means M2 in order to press them against the connecting ends 15 and 17. For the upper frame coupling elements 34 and 35, countersunk head screws are provided as means M3 in order to press them against the connecting ends 13 and 16.

[0078] Fig. 3 shows a side view of the right control head coupling element 31. Its inner side, which is provided with the toothing elements 38, can be seen. This illustration shows that the opposing tooth flanks 39a and 39b of the longitudinal tooth gap 39 are symmetrical in the present example, i.e. the opposing tooth flanks are inclined by the same angular amount. In contrast, the opposing tooth flanks 40a and 40b of the transverse tooth gap 40 are inclined differently, such that the tooth flank 40a, which is closer to the control head housing area 3, has a steeper angle of inclination a1 than the tooth flank 40b, which is further away from the control head housing area 3. The tooth flanks 41a and 41b of the transverse tooth gap 41 are again symmetrical.

[0079] The tooth flanks of the transverse teeth of the front connecting end 12 of the upper frame element 4 are provided with complementary angles of inclination so that those tooth flanks with the steeper angle of inclination can interact with one another. The design is expediently configured such that those complementary tooth flanks which have the steeper angle of inclination are braced against one another in the assembled state. The same applies to tooth flanks of the transverse teeth 23 and 24 which are provided on the front connecting end 14 of the lower frame element 7. In Fig. 3, a transverse tooth gap Q1 is provided with two tooth flanks ZI and Z2 and a transverse tooth gap Q2 with two tooth flanks Z3 and Z4. The tooth flanks ZI and Z3 are each provided with a steeper angle of inclination than the respective opposite tooth flank Z2 or Z4.

[0080] In the assembled state, the tooth flanks of the transverse teeth provided on the front connecting end 14 of the lower frame element 7 and the tooth flanks of the transverse teeth 40 on the front connecting end 12 of the upper frame element 4 are arranged such that those tooth flanks of the two connecting ends which each have the steeper angle of inclination are directed towards one another and, in the clamped state, generate an elastic force which forces the two connecting ends, i.e. the front connecting end 12 of the upper frame element 4 and the front connecting end 14 of the lower frame element 7, towards one another and clamps their end faces against one another. This serves to provide a strong front main connection H1.

[0081] The right steering head coupling element 31 has a contact surface A1 which is adapted to the outer surface of the steering head housing area 3, as well as a contact surface A2 adapted to the top tube element 2.

[0082] Fig. 4 shows a perspective of the right upper frame coupling element 35 of the bicycle frame 1 according to Fig. 1. Essentially an inner side of the right upper frame coupling element 35 can be seen, which comprises a form-fitting contour 49 with toothing elements 50. Associated toothing elements are provided on the rear connecting end of the upper frame element 4 and on the associated connecting end 16 of the seat post frame element 8. In the assembled state, they form a rear main connection H2 of the modular bicycle frame 1. While in the front main connection H1 the longitudinal tooth 27 and the transverse teeth 28 and 29 of the toothing elements 26 are arranged at the relevant connecting ends and the matching tooth gaps are located on the head tube coupling elements 30 and 31, the situation is reversed for the rear main connection H2, i.e.Here, the upper frame coupling elements 34 and 35 are provided with crossed teeth and the tooth gaps are located at the involved connecting ends, i.e. at the rear connecting end 13 of the upper frame element 4 and the upper connecting end 16 of the seat post frame element 8.

[0083] According to Fig. 4, the crossed teeth of the toothing elements 50 of the right upper frame coupling element 35 are arranged in a double cross shape, or two double cross-shaped regions 50a and 50b are provided, i.e. one double cross-shaped region per associated connecting end 13 or 16. In this example, the double cross-like arrangement has two parallel longitudinal teeth 51 and 52, which extend over both regions 50a and 50b and are arranged in the longitudinal direction L of the upper frame element 4. In addition, a transverse tooth 53 or 54 is provided for each region, which crosses both longitudinal teeth 51 and 52. The matching design of the connecting ends 13 and 16 of the upper frame element 4 and the seat post frame element 8 includes complementary tooth gaps.

[0084] The right upper frame coupling element 35 is further provided with a plurality of through-holes (55, 56, 57, 58) each for a screw. The through-holes are preferably provided on an outer side 59 of the upper frame coupling element 35 with a conical countersink 60 (countersink) to accommodate countersunk screws.

[0085] As Fig . 5 shows, unlike the control head

[0086] Coupling elements, the through openings (55, 56, 57, 58) of the right upper frame coupling element 35 are not arranged at crossing points, but are located between the two parallel longitudinal teeth 51 and 52 and away from the transverse teeth 53 and 54, respectively.

[0087] An upwardly directed section 61 of the right upper frame coupling element 35 has two further through-openings 62 and 63 which serve for connection to the associated left upper frame coupling element 34.

[0088] Fig. 6 shows a perspective view of a second exemplary embodiment of the bicycle frame 1 according to the invention, or rather its essential components. The arrangement of the components corresponds to the arrangement shown in Fig. 1. Identical parts (G1, G2, G3, G4, G5) can be seen, which are identical in the exemplary embodiment in Fig. 1. The identical parts are frame elements of the first category and frame elements of the third category, namely the upper frame element 4, the lower frame element 7 and the seat post frame element 8 (first category) as well as the left rear structure element 9 and the right rear structure element 10 (third category), the two rear structure elements (9, 10) forming the rear swing arm 11 when joined together.

[0089] Furthermore, Fig. 6 shows frame elements of the second category, namely coupling elements that are provided with connecting contours in the form of form-fitting contours, specifically coupling elements arranged in pairs in the present example. A pair of steering head coupling elements 64 and 65, a pair of seat tube coupling elements 66 and 67, and a pair of upper frame coupling elements 68 and 69 are provided.

[0090] These coupling elements (64, 65, 66, 67, 68, 69) form the frame elements of the second category. They function according to the same principle as the frame elements of the second category shown in Fig. 1; however, they differ in their size and details of their design. The steering head coupling element 65 has a connecting contour E5 and the steering head coupling element 64 is provided with a mirror-image connecting contour. The seat tube coupling elements 66 and 67 each have a connecting contour E6 and E7 respectively. The upper frame coupling element 69 has a connecting contour E8 and the upper frame coupling element 68 is provided with a mirror-image connecting contour.

[0091] A significant design difference, for example, is that an integrated spacer element 70 is provided on the left seat tube coupling element 66 and an integrated spacer element 71 is provided on the right seat tube coupling element 67. The two spacer elements 70 and 71 keep the upwardly directed rear connecting end 15 of the lower frame element 7 at a distance from the downwardly directed lower connecting end 17 of the seat post frame element 8. In this way, a bicycle frame 1 with a greater frame height RH1 is provided without having to change the essential frame elements, such as the upper frame element 4 and the lower frame element 7 compared to those in Fig. 1. According to the same principle, the upper frame coupling elements 68 and 69 are provided with integrated spacer elements, of which only the spacer element 72 of the right upper frame coupling element 69 can be seen in the perspective of Fig. 6.The upper frame coupling elements 68 and 69 have form-fitting contours with toothing elements, like those upper frame coupling elements 34 and 35 in Fig. 1. On the right upper frame coupling element 69 it can be seen that toothing elements 73 have two parallel longitudinal teeth 74 and 75 and two transverse teeth, a transverse tooth 76 which cooperates with the rear connecting end 13 of the upper frame element 4 and a transverse tooth 77 which cooperates with the upper connecting end 16 of the seat post frame element 8.

[0092] Fig. 7 shows a cross-section through the rear upwardly directed connecting end 15 of the subframe element 7 and the downwardly directed lower connecting end 17 of the seat post frame element 8, which are connected to the pair of seat tube coupling elements 66 and 67. The cross-sectional view shows the cross-sections of transverse teeth 78 and 79 of the connecting end 15 and transverse teeth 80 and 81 of the connecting end 17. The tooth flanks of the transverse teeth also have different angles of inclination there. The tooth flanks of the seat tube coupling elements 66 and 67 are designed to be complementary to this.

[0093] In the sectional view it can be seen that those tooth flanks which each have a steeper inclination angle a1 are in contact with one another, while a gap can be seen between tooth flanks which have a flatter inclination angle a2. The tooth flanks which are in contact are clamped against one another, whereby the desired strong main connection H3 is created. Furthermore, Fig. 7 shows how the spacer elements 70 and 71 of the seat tube coupling elements 66 and 67, which extend between the connecting end 15 of the subframe element 7 and the connecting end 17 of the seat post frame element 8, keep these connecting ends at a distance in order to provide a frame height RH2 > RH1. In the present example, a gap 82 remains between the opposing spacer elements 70 and 71.This ensures that the tooth flanks in contact can always be preloaded against each other; it is avoided that preloading of the tooth flanks is thwarted by contact between the opposing spacer elements 70 and 71.

[0094] In order to provide a frame height > RH2, a further embodiment of a seat tube coupling element pair can be provided, the spacer elements of which create a correspondingly greater distance between the connecting end 15 of the subframe element 7 and that connecting end 17 of the seat post frame element 8.

[0095] Fig. 8 shows a perspective view of the right steering head coupling element 65 of the bicycle frame 1 in Fig. 6. This is a larger modular variant of the right steering head coupling element 31 shown in Fig. 2. As can be seen, a form-fitting contour is provided which has two areas 83 and 84 with toothed elements. Each area comprises tooth gaps in a double-cross arrangement according to the same principle as in the example in Fig. 2. One area 83 interacts with the front connecting end 12 of the upper frame element 4 and the other area 84 interacts with the front connecting end 14 of the lower frame element 7 in the assembled state.

[0096] According to Fig. 9, the two regions 83 and 84 are spaced apart by a distance X2. The distance X2 is greater than a distance XI of the corresponding regions of the toothed elements according to Fig. 3.

[0097] Each area 83 and 84 has a double-cross-shaped tooth gap structure, which is provided for the purpose of positive engagement with the front connecting end 14 of the sub-frame element 7. This requires that area 83 has a double-cross-shaped structure of the tooth gaps, which is identical to the double-cross-shaped structure of the tooth gaps in Fig. 3. Likewise, that area 84 must have an identical double-cross-shaped structure of the tooth gaps, as in Fig. 3, in order to be compatible with the identical parts G1 and G2. For the identically designed double-cross-shaped tooth gaps, reference is therefore made to the reference numerals in Figs. 2 and 3.

[0098] 9, an offset Y is provided between the bending region of the longitudinal tooth gap 39 and the longitudinal tooth gap provided for the connecting end of the subframe element 7, which offset Y serves to increase the size of the bicycle frame 1 or is caused by the increase in size. A spacer element 65a of the right steering head coupling element 65 forms an area spatially and physically enlarged by the distance X and the offset Y. The spacer element 65a is solid in the present example. This promotes a strong front main connection Hl for this size variant of the bicycle frame 1. The enlargement of the bicycle frame by means of the distance X and the offset Y essentially serves to provide a greater frame length RL2 (cf. Fig. 11). In conjunction with a greater frame height RH2, the bicycle frame 1 according to Fig. 6 is created, which is larger than the bicycle frame 1 according to Fig. 1.

[0099] The right-hand steering head coupling element 65 also has a contact surface A3, which is adapted to the outer surface of the steering head housing area 3, as well as a contact surface A4, which is adapted to the top tube element 2. The contact surface A3 is larger than the contact surface A1 according to Figs. 2 and 3. The same applies to the contact surface A4, which is larger than its counterpart, namely the contact surface A2 of Figs. 2 and 3.

[0100] A comparison of the two frame sizes is shown in the side views of Figures 10 and 11. Figure 10 shows a side view of the assembled bicycle frame according to Figure 1 and Figure 11 shows a side view of the assembled larger bicycle frame according to Figure 6. The frame height RH2 and the frame length RL2 are each greater than the frame height RH1 and the frame length RL1 respectively according to Figure 10.

[0101] According to Fig. 11, an abutment element 85 is provided for the purpose of mounting a damper element S1 (shown in dashed lines) for the rear swing arm 11. The abutment element 85 is arranged on the subframe element 7. The abutment element 85 forms a first pivot point P1 for the damper element S1. It is a component of the common part G2. A second pivot point P2 for the damper element S1 is provided on the rear swing arm 11.

[0102] Furthermore, a means 86 for accommodating an accumulator for electrical energy can be provided. In the example of Fig. 11, the means 86 is shown as an alternative embodiment by means of a dashed line on the subframe element 7. It is advantageously used when an electric assist motor unit (not shown) is arranged in the pedal drive housing area 6 of the subframe element 7.

[0103] List of reference symbols

[0104] 1 bicycle frame

[0105] 2 top tube element

[0106] 3 Control head housing area

[0107] 4 upper frame element

[0108] 5 down tube element

[0109] 6 Pedal drive housing area

[0110] 7 Subframe element

[0111] 8 Seat post frame element

[0112] 9 Rear element

[0113] 10 Rear section element

[0114] 11 Rear swing arm

[0115] 12 front connecting end top tube element

[0116] 13 rear connecting end top tube element

[0117] 14 front connecting end of down tube element

[0118] 15 rear connection end (seat post frame ends)

[0119] 17 lower connection end

[0120] 18 Form fit (to 14)

[0121] 19 Gear element (front connection end 14 of 7 )

[0122] 20 teeth

[0123] 21 gaps between teeth

[0124] 22 Longitudinal tooth 23 Transverse tooth

[0125] 24 transverse tooth

[0126] 25 bending area

[0127] 27 Longitudinal tooth

[0128] 28 transverse tooth

[0129] 29 transverse tooth

[0130] 30 Steering head coupling element (left)

[0131] 31 Steering head coupling element (right)

[0132] 32 Seat tube coupling element (left)

[0133] 33 Seat tube coupling element (right)

[0134] 34 Upper frame coupling element (left)

[0135] 35 Upper frame coupling element (right)

[0136] 36 left toothing element (front at 4)

[0137] 38 Gear element (to 31)

[0138] 39 Longitudinal tooth gap (to 31)

[0139] 39a Tooth flank

[0140] 39b Tooth flank

[0141] 40 transverse tooth gap (to 31)

[0142] 40a Tooth flank, steeper

[0143] 40 tooth flank, steeper

[0144] 41 transverse tooth gap (to 31)

[0145] 41a Tooth flank, steeper

[0146] 41b Tooth flank, steeper

[0147] 42 exterior surface

[0148] 43 conical depression

[0149] 44 Conical countersink

[0150] 45 - 48 screw hole

[0151] 49 Form-fitting contour

[0152] 50 gear elements

[0153] 50a double cross-shaped area

[0154] 50b double cross-shaped area

[0155] 51 Longitudinal tooth 52 Longitudinal tooth

[0156] 53 transverse tooth

[0157] 54 transverse tooth

[0158] 55 - 58 through opening

[0159] 59 Outside

[0160] 60 countersink

[0161] Section 61

[0162] 62 through opening

[0163] 63 Through opening

[0164] 64 Steering head coupling element (left)

[0165] 65 Steering head coupling element (right)

[0166] 65a spacer element

[0167] 66 Seat tube coupling element (left)

[0168] 67 Seat tube coupling element (right)

[0169] 68 Upper frame coupling element (left)

[0170] 69 Upper frame coupling element (right)

[0171] 70 integrated spacer element (left)

[0172] 71 integrated spacer element (right)

[0173] 72 integrated spacer element

[0174] 73 Gear element

[0175] 74 Longitudinal tooth

[0176] 75 Longitudinal tooth

[0177] 76 transverse tooth

[0178] 77 transverse tooth

[0179] 78 transverse tooth

[0180] 79 transverse tooth

[0181] 80 transverse tooth

[0182] 81 transverse tooth

[0183] 82 gap

[0184] 83 Area

[0185] 84 Area

[0186] 85 Abutment element 86 Means (for holding an accumulator)

[0187] Gl common part

[0188] G2 common part

[0189] G3 common part

[0190] G4 common part

[0191] G5 common part

[0192] L Longitudinal direction (top tube element)

[0193] D Longitudinal direction (Companies)

[0194] ZI tooth flank

[0195] Z2 tooth flank

[0196] Z3 tooth flank

[0197] Z4 tooth flank

[0198] Ql transverse tooth gap

[0199] Q2 transverse tooth gap

[0200] Al contact surface

[0201] A2 contact surface

[0202] A3 contact surface

[0203] A4 contact surface

[0204] PI articulation point

[0205] P2 articulation point

[0206] S Damper unit al steeper inclination angle a2 flatter inclination angle

[0207] RH1 frame height

[0208] RH2 frame height

[0209] RL1 frame length

[0210] RL2 frame length

[0211] Cl - C 6 connection contour

[0212] El - E8 connection contour

[0213] Ml - M3 means for preload

[0214] T Swing bearing housing area

Claims

Patent claims 1. Modular bicycle frame (1) comprising several frame elements (4, 7, 8, 9, 10, 30, 31, 32, 33, 34, 35, 64, 65, 66, 67, 68, 69) and housing areas (3, 6, 7), wherein frame elements (4, 7, 8) of a first category are provided, each having at least one connecting end (12, 13, 14, 15, 16, 17), characterized in that a connecting end (12, 13, 14, 15, 16, 17) of at least one first frame element (4, 7, 8) and at least one connecting end (12, 13, 14, 15, 16, 17) of a second frame element (4, 7, 8) are aligned with each other in the connected state are arranged, and wherein these connecting ends (12, 13, 14, 15, 16, 17) of the frame elements (4, 7, 8) each have at least one connecting contour (G1, C2, C3, C4, C5, C6), preferably a form-fitting contour, with the proviso that at least one frame element of a second category is provided, which is designed as a coupling element (30, 31, 32, 33, 34, 35, 64, 65, 66, 67, 68, 69),wherein the coupling element (30, 31, 32, 33, 34, 35, 64, 65, 66, 67, 68, 69) in turn, at least one connecting contour (El, E2, E3, E4), preferably a form-fitting contour, which connecting contour (El, E2, E3, E4) is designed to be partially complementary to the connecting contour (Cl, C2, C3, C4, C5, C6) of the connecting end (12, 13, 14, 15, 16, 17) of the first frame element (4, 7, 8) and partially complementary to the connecting contour (Cl, C2, C3, C4, C5, C6) of the connecting end (12, 13, 14, 15, 16, 17) of the second frame element (4, 7, 8).

2. Modular bicycle frame (1) according to claim 1, characterized in that the first frame element is provided with a top tube element (2) and a steering head housing area (3).

3. Modular bicycle frame (1) according to claim 2, characterized in that the top tube element (2) and the steering head housing area (3) are combined to form an integrated top frame element (4).

4. Modular bicycle frame (1) according to one of claims 1 to 3, characterized in that the second frame element is provided with a down tube element (5) and a pedal drive housing area (6).

5. Modular bicycle frame (1) according to claim 4, characterized in that the down tube element (5) and the pedal drive housing area (6) are combined to form an integrated subframe element (7).

6. Modular bicycle frame (1) according to one of claims 1 to 5, characterized in that a third frame element of the first category is designed as a saddle support frame element (8).

7. Modular bicycle frame (1) according to claim 6, characterized in that of the following frame elements: upper frame element (4), lower frame element (7) and seat post frame element (8), at least one frame element is provided with two connecting ends each, and that both connecting ends each have at least one form-fitting contour.

8. Modular bicycle frame (1) according to claim 7, characterized in that at each connecting end (12, 13, 14, 15, 16, 17) two form-fitting contours are arranged symmetrically on the left and right on opposite sides.

9. Modular bicycle frame (1) according to claim 7 or 8, characterized in that the form-fitting contours provided at the connecting ends (12, 13, 14, 15, 16, 17) of the frame elements are provided with toothing elements (19, 36, 50, 73).

10. Modular bicycle frame (1) according to one of claims 1 to 9, characterized in that two coupling elements (30 / 31, 32 / 33, 34 / 35, 64 / 65, 66 / 67, 68 / 69) are arranged symmetrically, and that each coupling element is provided with a connecting contour (E1, E2, E3, E4, E5, E6, E7), preferably a form-fitting contour.

11. Modular bicycle frame (1) according to one of claims 1 to 10, characterized in that the form-fitting contours of the frame elements (4, 7, 8) are provided with toothing elements (19, 36), and that the form-fitting contour of each coupling element ments is provided with toothed elements (50, 73).

12. Modular bicycle frame (1) according to one of claims 9 to 11, characterized in that such toothing elements (19, 36, 50, 73) are provided which have teeth (20, 22, 23, 24, 27, 28, 29, 51, 52, 53, 54, 74, 75, 76, 77, 78, 79, 80, 81) with a wedge-shaped cross-section and intermediate tooth gaps (21, 39, 40, 41, Q1, Q2).

13. Modular bicycle frame (1) according to one of claims 9 to 12, characterized in that the toothing elements (19, 36, 50, 73) of the frame elements (4, 7, 8, 9, 10, 30, 31, 32, 33, 34, 35, 64, 65, 66, 67, 68, 69) each have a longitudinal tooth (22, 27, 51, 74, 75) and at least one transverse tooth (23, 24, 28, 29, 53, 54, 76, 77, 78, 79, 80, 81), and that the transverse tooth preferably crosses the longitudinal tooth orthogonally.

14. Modular bicycle frame (1) according to claim 12 or 13, characterized in that in the case of the toothing elements (50, 73) of the coupling element (30, 31, 32, 33, 34, 35, 64, 65, 66, 67, 68, 69), the tooth gaps (49, 40, 41, Q1, Q2) are arranged in a cross-like manner in order to enable the engagement of the coupling element with the longitudinal tooth (22, 27) and the transverse tooth (23, 24, 28, 29) of the frame element (4, 7, 8).

15. Modular bicycle frame (1) according to one of claims 10 to 14, characterized in that a means (M1, M2, M3) for generating a prestress between the coupling element (30, 31, 32, 33, 34, 35, 64, 65, 66, 67, 68, 69) and the frame elements involved (4, 7, 8) is provided.

16. Modular bicycle frame (1) according to claim 15, characterized in that the means (M1, M2, M3) for generating the preload comprises at least one screw, by means of which the coupling element (30, 31, 32, 33, 34, 35, 64, 65, 66, 67, 68, 69) the frame elements involved can be prestressed.

17. Modular bicycle frame (1) according to claim 16, characterized in that the connecting ends (12, 13, 14, 15, 16, 17) of the frame elements (4, 7, 8) are each provided with at least one hole (45, 46, 47, 48), preferably a blind hole, for screwing in the screw, and in that the coupling element (30, 31, 32, 33, 34, 35, 64, 65, 66, 67, 68, 69) is provided with at least two through-openings (55, 56, 57, 58) for screws, one through-opening (55, 56) for connection to a first frame element (4, 7, 8) and the second through-opening (57, 58) for Connection to a second frame element (4, 7, 8).

18. Modular bicycle frame (1) according to claim 5, characterized in that the subframe element (7) is provided with a swing arm bearing housing area (T) for a rear swing arm (11).

19. Modular bicycle frame (1) according to claim 18, characterized in that at least one frame element of a third category is provided, namely a rear frame element which serves as a rear swing arm (11), or preferably two rear frame elements are provided, namely a left rear frame element (9) and a right rear frame element (10), which are firmly connected to one another and form the rear swing arm (11), and that the respective rear- swing arm is mounted on the swing arm bearing housing area (T).

20. Modular bicycle frame (1) according to claim 19, characterized in that an abutment element (85) is arranged on the subframe element (7) for the purpose of mounting a damper element (S1) for the rear swing arm (11).

21. Modular bicycle frame (1) according to one of claims 5 to 20, characterized in that the pedal drive housing area (6) of the subframe element (7) is adapted to receive an assist motor unit provided with a pedal crank.

22. Modular bicycle frame (1) according to one of claims 5 to 21, characterized in that the subframe element (7) has a means (86) for receiving an energy storage device, preferably an accumulator for electrical energy.

23. Modular bicycle frame (1) according to one of claims 1 to 22, characterized in that at least one frame element (4, 7, 8, 9, 10, 30, 31, 32, 33, 34, 35, 64, 65, 66, 67, 68, 69) and / or a housing region (3, 6, T) is made of a plastic which is selected from the following group of plastics: polyamide, polyacetal / polyoxymethylene, polyethylene, polypropylene, polycarbonate, polyvinyl chloride, polytetrafluoroethylene, acrylonitrile-butadiene-styrene, polyketone, polyetherketone, polyetheretherketone, polysulfone, polybutylene terephthalate, polyphthalamide, polyphenylene sulfide, polyphenylsulf on, thermoplastic polyurethane, thermoplastic elastomer.

24. Modular bicycle frame (1) according to claim 23, characterized in that the plastic contains at least one filler in the form of reinforcing particles and / or reinforcing fibers (compound).

25. Modular bicycle frame (1) according to claim 23 or 24, characterized in that the frame element (4, 7, 8, 9, 10, 30, 31, 32, 33, 34, 35, 64, 65, 66, 67, 68, 69) is manufactured by injection molding.

26. Modular series for geometrically similar bicycle frames (1) according to one of claims 1 to 25, comprising frame elements (4, 7, 8) of the first category, which are designed as identical parts (G1, G2, G3), and comprising frame elements (30 / 31, 32 / 33, 34 / 35, 64 / 65, 66 / 67, 68 / 69) of the second category, which are designed as modular parts.

27. Modular series according to claim 26, characterized in that the module parts of the second category comprise a series of coupling elements as frame elements (30 / 31, 32 / 33, 34 / 35, 64 / 65, 66 / 67, 68 / 69) with stepped sizes.

28. Modular series according to claim 26 or 27, characterized in that the module parts of the second category comprise a series of spacer elements with stepped sizes or of coupling elements (64 / 65, 66 / 67, 68 / 69) with integrated spacer elements (65a, 70, 71, 72).

Images