EP2396216A1

EP2396216A1 - Wheel drive

Info

Publication number: EP2396216A1
Application number: EP10703405A
Authority: EP
Inventors: Rudolf Frei
Original assignee: Individual
Current assignee: FIDRIVE SWISS AG
Priority date: 2009-02-16
Filing date: 2010-02-01
Publication date: 2011-12-21
Also published as: WO2010091524A1; CN102317143A; CH700460A2

Abstract

The invention relates to a wheel drive (1), comprising a wheel axle (4), a hub housing (6) which is rotatably mounted on the wheel axle (4) by way of first pivot bearings (5), and a driving motor (8) which is arranged in the hub housing (6) and by which the hub housing (6) can be caused to perform a rotational movement about the wheel axle (4), wherein the wheel drive (1) should be mounted to the axle bracket (2) of a light vehicle. At least at a face end, the wheel axle (4) comprises a central hollow region, into which a tensioning element (9) can be inserted. In the mounted state of the wheel drive, the tensioning element (9) protrudes from the hollow region in the longitudinal direction of the wheel axle (4) over the end of the wheel axle (4) to the outside, and at the protruding end a tensioner pressing surface (10) is configured, which can be pressed inward in the longitudinal direction of the wheel axle (4) and enables the axle bracket (2) to be pressed against a face pressing surface (11) of the wheel axle (4) that rests against the axle bracket (2). Said wheel drive (1) has a simple design and a light weight. It can be easily and quickly fastened to and removed from the axle bracket of a light vehicle.

Description

Wheel Drive

The invention relates to a wheel drive according to the preamble of claim 1.

The present invention relates to wheel drives in which the drive for a wheel is arranged directly in a hub shell on the wheel. Such wheel drives are particularly suitable for light vehicles such as bicycles and they generate a rotational movement between the wheel axle and the hub shell. For this purpose, a torque must be achieved between the wheel axle and the hub shell of a drive motor. The hub shell is rotatably mounted on the wheel axle with first pivot bearings on the wheel axle.

When a transmission is interposed between the drive motor and the hub shell, for example, a low-speed high-torque wheel drive can be provided with a high-torque, low-torque drive motor. The high-speed rotating motor part is preferably mounted rotatably on the wheel axle with at least one second rotary bearing. There are wheel drives with a planetary gear in which arranged between a arranged on the rotating motor part sprocket and connected to the hub shell sprocket transmission gears, wherein the transmission gears are rotatably mounted on a arranged on the wheel axle gear part.

The hub shell is rigidly connected to the rolling surface of the wheel. The diameter of the rolling surface, the type of drive motor and the type of transmission are selected according to the desired drive behavior and matched to each other. DE 602 09 510 T2 shows a wheel drive with a non-shiftable transmission. Wheel drives with shiftable transmissions are known, for example, from DE 100 56 597 A1 and DE 692 11 558 T2.

The drive motor of the wheel drive is preferably an electric motor. It would also be possible to use an internal combustion engine or a hydraulic drive. To supply power to the motor used, at least one supply line must be routed into the hub shell. If control signals are also transmitted to or from the engine, appropriate control lines or control Links. For an electric motor, the number of connections required for the supply and, if necessary, for the control depends on the selected motor type. In an internal combustion engine, the fuel must be supplied and at least one gas cable must be provided.

The wheel axle is attached to an axle bracket of the light vehicle. In a bicycle, the axle holder is designed as a fork. In order for the light vehicle to be set in motion by the wheel drive, the axle must be firmly connected to the axle mount. According to the known solutions, for example according to DE 602 09 510 T2, the cylindrical outer surface of the wheel axle is provided at both ends with a thread, but which is interrupted along the circumference in two mutually remote areas of parallel Achsaussenflächen. These axle outer surfaces are introduced as narrowed end regions in a form-fitting manner into slot-shaped openings of adaptation members, wherein the adjustment members are fastened to the fork of a bicycle. With screwed onto the broken threads of the wheel axle nuts, the wheel axle is clamped to the fork or its adjustment members. The broken threads can be damaged, making it difficult to tighten or loosen the nuts. In addition, a desired tightening torque of the nuts must be checked only with precision tools.

The high torques in the only slightly spaced parallel Achsaussenflächen the wheel axle, which act due to the wheel drive from the axis of the slots of the fork, can lead to wear in the form of positive connection. If the wear is sufficiently large, it can lead to a spin of the axle in the slots of the fork, which is connected to a twisting of the lines or the cable feed. For standard slot forks, the radius at the inner end of a slot matches the slot width. The outer diameter of the wheel axle is greater than the slot width due to the narrowed end portions. Therefore, the axis can not be fully applied to the curvature of the inner slot end of the fork. If the wheel axle something of the inner

Slot end is spaced, so it is closer to the open end of the fork slot, where the torque generated by the torque easier to widen the slot.

In order to allow the supply of lines to the drive motor, the wheel axle according to DE 602 09 510 T2 is tubular, wherein the lines on a Front side of the wheel axle axially out of this exit. Because the cables are guided outwards in the wheel axle, they pass outwards inside a first pivot bearing. The cables are routed in a cable to a connector. Since the plug has a larger diameter than the wheel axle, the nuts and washers must be strung on the cable before attaching the plug. This assembly is complex and error-prone. In addition, the laterally projecting cable is at risk. If the bike falls sideways or strikes an obstacle, the cable is likely to be injured.

In an embodiment in which the lines are not centrally outwards, but they must still be performed in the fixed inner part of a first pivot bearing to the outside. For this purpose, the diameter of the first pivot bearing is increased in known solutions and this is placed on an intermediate piece. The intermediate piece is fixedly connected to the wheel axle and comprises a passage in the axial direction for the lateral addition of leads. The intermediate piece and the larger bearing lead at least on one side to a larger and more complex design and more weight, which is undesirable. The outgoing lines are susceptible to injury.

The inventive task is now to find a simple and lightweight wheel drive, which can be easily and quickly attached to the axle holder of a vehicle, especially at fork slots, and solved. In particular, even at high torques wear and a spinning of the wheel axle should be prevented. Another object is that the lines are guided injury-safe.

The main object is achieved by a drive hub with the features of claim 1. The dependent claims describe alternative or advantageous embodiments, which solve the other objects.

In the solution of the problem has been recognized that the wheel axle should have a central hollow area at least at a front end of the wheel axle, which is kept free of lines and in which a clamping element can be used. To fasten the wheel drive to an axle bracket, a clamping element is inserted into the at least one central hollow area. The clamping element is in the mounted state of the wheel drive from the hollow area in the longitudinal direction of the wheel axle the end of the wheel axle outwards, or away from the wheel axle, and includes at the free end in the longitudinal direction of the wheel axle against the inside, and against the wheel axis out, compressible tensioner pressing surface. When the wheel drive is mounted on an axle bracket, the tensioner pressing surface abuts the axle bracket on the outside and presses it against an axle-mounted end-pressing surface of the wheel axle. The clamping element extends outside the wheel axle through a passage, in particular a slot, the axle holder.

The wheel axle is preferably designed as a hollow axle and the tensioning element as a quick-release, wherein the quick-release comprises a rod-shaped part which can be inserted into the hollow axle and tensioner pressing surfaces pressable against the inside at both ends in the bar direction. The clamping or pressing is preferably achieved via a pivotable lever with eccentric arrangement, wherein the clamping can optionally also be achieved with a screw device. When tightening the wheel drive on a Achshalterung or fork with two spaced legs, the tensioner pressing surfaces are outside of the axle bracket. Inside the legs of the Achshalterung lie forehead pressing surfaces of the hollow wheel axle. The tensioned clamping element thus firmly presses the wheel axle between the legs of the axle holder which are present on both sides. The clamping element extends outside the wheel axle through bushings, in particular slots, the axle holder. This solution is simple and the required parts can be mounted and replaced with little effort. At both lateral end regions of the wheel axle, the hub shell is rotatably mounted on the wheel axle via first rotary bearings. The wheel drive is mounted on the axle bracket of a light vehicle.

In order to be able to absorb the high torques between the wheel axle and the axle brackets in a torsion-free manner, positive engagements are formed between the axle brackets and the end press surfaces of the hollow wheel axle resting thereon. In the common with forks slots the wheel axle comprises two each on one end face on the end-pressing surface in the slots of the fork projecting engagement elements. The engagement elements are located radially outside the tensioning element relative to the center of the wheel axle. As a result, they can already absorb higher torques without wear than the parallel axis outer surfaces known from the prior art, which are indeed formed radially within the axle diameter. The engagement elements can radially outward far enough extend, as is necessary for the safe torque absorption. Because the slots of bicycle forks can by default have two different orientations, it is advantageous if the engagement elements can be fastened in two different circumferential positions on the end-pressing surfaces. Preferably, the end-pressing surfaces are radially expanded over the outer diameter of the wheel axle, so that the best possible support of the end-pressing surfaces is ensured at the Achs- holders.

According to a preferred embodiment, the end-pressing surfaces are formed on plug-in end parts of the wheel axle. So that the torques are transmitted from the middle part of the hollow wheel axle to the inserted end parts substantially free of play, the mated parts in the mutual contact area comprise form-fitting adapted engagement shapes, such as gears, which extend in the circumferential direction about the center of the wheel axle. In order to avoid the occurrence of play, for example, a hard chromium steel is used for the middle part of the wheel axle and an anticorrudal softer material, in particular an aluminum alloy, is used for the end parts.

One of the two end parts preferably comprises a cable guide, which takes over the lines guided from the wheel drive at a cable channel of the central part of the hollow wheel axle and radially away relative to the wheel axis, for example, to a connector which is arranged on the end part with the cable guide. The termination part with the cable guide preferably comprises a watertight plug. In this embodiment, the termination part with the cable guide the cable and the plug a unit that greatly facilitates mounting and dismounting because the secondary lines are not connected during the work. With a simple plug-in or pull-out handle, the secondary lines can be connected or disconnected.

Because the terminating part connects to the inside of the assigned axle mount, the cable is extremely well protected against damage, even if the radially leading cable guide is slightly away from the axle mount and out to the outside. Because the cable guide is located at the end of the wheel axle, the tensioner can be removed without it remaining in contact with the cable. If in the hollow axle a cable duct parallel to the longitudinal direction tion is formed, lines can be led out laterally within the first pivot bearing from the hub shell laterally without an intermediate piece between the wheel axle and the first pivot bearing is used. It can be used a first pivot bearing whose inner diameter corresponds to the outer diameter of the wheel axle, which allows a small and lightweight design.

The preferred electric drive motor includes a stator with the windings. The stator is arranged torsion-proof on the wheel axle and is held on the drive axle via a form-locking rotation lock. The twist lock comprises grooves on the wheel axle and on the stator in the longitudinal direction of the wheel axle and a common wedge inserted in the latter. The rotating motor part comprises the windings facing permanent magnets. It goes without saying that the rotating part may optionally comprise windings, in which case rotary feeders are necessary, which leads to a more complicated construction. The rotating motor part is rotatably mounted on the wheel axle via at least one second rotary bearing and comprises an outer sprocket surrounding the wheel axle. A planetary gear comprises in addition to the outer ring gear a rotatably fixed to the wheel axle arranged gear part and rotatably mounted transmission gears. The hub shell comprises an inner ring gear of the planetary gear. The rotation of the outer sprocket is transmitted via the transmission gears on the inner sprocket.

In order to provide a low-noise wheel drive, a floating bearing is selected between the wheel axle and the transmission part and elastic bearing elements are used in the bearings of the transmission gears. A positive torsion protection comprises on the wheel axle and on the gear part at least one pair of grooves in the longitudinal direction of the wheel axle and inserted into this each a common wedge. It goes without saying that instead of an inserted wedge on the gear part or optionally on the wheel axle, a tooth or a tooth trace can be formed.

A particularly advantageous embodiment of the wheel drive is designed so that all components can be inserted one after the other, on and in the middle part of the wheel axle. In order to bring the pivot bearings simply to the correct position, the middle part of the wheel axle comprises two cylindrical sections and a radially projecting stop for a second pivot bearing therebetween. In the preferred embodiment tion two standard ball bearings are pushed together with the rotor of the drive motor on the middle part of the wheel axle and arranged side by side at the stop. Subsequently, a wedge is inserted in the groove of the torsion protection of the stator and the stator pushed onto the middle part of the wheel axle until it is in the desired position on the rotor at the wheel axle. It goes without saying that instead of an inserted wedge on the stator or optionally on the wheel axle, a tooth or a tooth trace can be formed. When placing the cable with the lines through the axial cable channel is led to the outside. Subsequently, a first partial housing of the hub housing with a first pivot bearing is partially pushed onto the middle part of the wheel axle in the stator.

From the opposite end of the middle part of the wheel axle, the transmission part with the transmission gears and a wedge between the wheel axle and the transmission part is attached. Subsequently, a second housing part of the hub shell with a second pivot bearing can be partly placed on the middle part of the wheel axle. The two housing parts are connected to each other, in particular screwed together.

Subsequently, end parts of the wheel axle are attached to both sides of the middle part, whereby their teeth are inserted into one another under the first pivot bearings. The terminating part with the continuing cable guide is arranged at the stator or at the exiting cable so that the cable passes from the axial channel section of the middle part of the wheel axle into the radially leading away channel section of the terminating part. At the two end parts of the engagement elements are attached, which protrude for the usual Achshalterungen or forks with slots preferably from the end-pressing surfaces of the wheel axle.

The closed hub shell and the fully assembled wheel axle form a wheel drive in which all parts are plugged together and the housing was screwed without the need for fixing on the axis more fasteners were needed. The assembly is thus easy and it is only a minimum number of parts needed. At the wheel drive, the remaining parts of a wheel, preferably in the form of spokes and a rim, and optionally a brake disc are mounted. Subsequently, the wheel can be mounted with the wheel drive on a fork, in which the wheel axle is inserted into the mounting area of the fork and a quick release is inserted through the central cavity of the wheel axle. By clamping the quick release, the tensioner pressing surfaces on both sides of the outside of legs of the fork and these pressed against the inside of the legs of the fork abutting end-pressing surfaces of the wheel axle.

Advantageously, the end part is designed in two or more parts, so that in the case of a break the simple interchangeability of the part is ensured. This is particularly advantageous in the case of carbon as a material for the final part. Particularly advantageous is the formation of a predetermined breaking point in order to be able to predetermine the location of the break and thus to facilitate the replacement of the part further. Furthermore, it is advantageous to make the cable in the interior of the closure part so that it is releasably formed in the event of breakage of the broken part and is designed easily and quickly fastened to a new end part. Thus, advantageously only the broken part has to be replaced.

The drawings illustrate the invention with reference to an embodiment to which it is not limited. It shows

1 shows a longitudinal section through a wheel drive with a schematically drawn fork,

2 shows a longitudinal section through a wheel axle which has a central hollow area only at the two ends,

3a and 3c are views of the two end faces of a hollow wheel axle, Figs. 3b and 3d are longitudinal views of a hollow wheel axle, Figs. 4a and 4b are views of a termination cable management, and

Fig. 4c front and side view of an engagement member which can be fixed in two different positions on the end part with cable guide according to Fig. 4b.

Fig. 1 shows a wheel drive 1 which is complained to a schematically illustrated fork 2 of the front wheel of a bicycle. The fork 2 comprises at the two free ends the slots 3 for mounting a wheel. The wheel drive 1 comprises a three-part wheel axle 4, which is composed of a middle part 4a and a first and a second end part 4b and 4c. A two-part hub shell 6 is rotatably mounted on the wheel axle 4 via first pivot bearings 5, the two partial housings 6 a and 6 b being connected to one another via a thread 7. In the hub shell, a drive motor 8 is arranged, with which the hub shell 6 can be set about the wheel axle 4 in rotary motion.

In the illustrated embodiment, the wheel axle 4 is formed as a hollow axle, in which the central hollow portion extends through the entire wheel axle 4. In the assembled state, a clamping element 9 is arranged in the central cavity of the wheel axle 4, which extends through the entire central cavity and protrudes on both sides over the ends of the wheel axle 4 and at both free ends depending on a pressable in the longitudinal direction of the wheel axle 4 against inside tensioner pressing surface 10 includes. The tensioner pressing surfaces 10 abut on both sides on the outside at the free ends of the fork 2, wherein the clamping element 9 is guided through the two slots 3. At both lateral ends of the wheel axle 4 end-pressing surfaces 11 are formed which are arranged on the inside of the fork 2.

The clamping element 9 shown is designed as a quick release and includes a pivotable lever 12 with eccentric 13. In order to adjust the voltage or the distance between the tensioner pressing surfaces 10 something, the clamping element 9 comprises at least at one point between two parts of the clamping element 9 a thread. The eccentric assembly 13 presses the tensioner pressing surfaces 10 against the inside during clamping with the lever so that the end pressing surfaces 11 are clamped between the free ends of the fork 2. The clamping element 9 has in the assembled state of the wheel drive 1 between the tensioner pressing surfaces 10 and the end-pressing surfaces 11 a cylindrical portion, wherein the diameter of the cylindrical portion is adapted to the width of the slots of the Ga- at 2.

It goes without saying that instead of a quick release another clamping element, such as a threaded rod with two nuts, could be used, but then the assembly would be less easy. The wheel drive 1 comprises at both end-pressing surfaces 11 of the wheel axle 4, an engagement member 14 which ensures a positive engagement with the fork 2, preferably at slots of the fork 2, in the mounted state of the wheel drive 1, wherein the engagement elements 14 relative to the center of the wheel axle 4 radially outside the cylindrical portions of the clamping element 9 between the tensioner pressing surfaces 10 and the end-pressing surfaces 11 are arranged.

Now, if the first and the second end part 4b and 4c due to the engagement elements 14 rotatably connected to the fork 2, must also be formed between the end parts 4b, 4c and the middle part 4a of the wheel axle a rotation, so that the entire wheel axle 4th Turn firmly on the fork 2 is mounted. For this purpose, the adjoining regions of the middle part 4a and each end part 4b, 4c have mating engagement ends which preferably comprise gearing 15, which extend in the circumferential direction around the center of the wheel axle 4. The first pivot bearings 5 surround the mated engagement ends, thereby increasing the stability of the connections of the middle part 4a to the end parts 4b, 4c.

Because the rotation assurance yes serves that the torque of the drive motor 8 leads to a rotation of the hub shell 6 about the wheel axle 4, a part of the drive motor 8 (stator) must be rotatably connected to the wheel axle 4. In the illustrated simple embodiment, this is achieved in that in the middle part of the wheel axle 4 and in a stator 16 mutually associated grooves 17 are formed and a radially extending over both grooves 17 wedge 18 is inserted therein.

The drive motor is an electric motor with a wound stator 24 which is fixedly connected to the stator 16. The rotating motor part 25 is rotatably mounted with two second pivot bearings 26 on the wheel axle 4 and comprises a Radach- se 4 enclosing outer sprocket 27 which engages in transfer gears 28 of a planetary gear. The Übertagungszahnräder 28 are rotatably mounted on a rotationally fixed on the wheel axle 4 arranged gear part 29. The hub shell 6 includes an inner ring gear 30, wherein the rotation of the outer ring gear 27 is transmitted via the transmission gears 28 on the inner ring gear 30 and thus on the hub shell 6. Between the wheel axle 4 and the transmission part 29 a floating bearing and a positive rotation assurance is formed. The anti-rotation device illustrated comprises grooves 17 on the wheel axle 4 and on the transmission part 29 in the longitudinal direction of the wheel axle 4 and a common wedge 18 inserted therein. For low-noise mounting of the transfer gears 28, third rotary bearings 31 are mounted on retaining bolts 33 via elastic support elements 32.

In the middle part 4a of the wheel axle 4, an axial cable channel 19 is formed to the second end part 4c. In the second cable part 4c, a further cable guide with a further axial channel section 20 and a channel section 21 leading radially away relative to the wheel axle 4 adjoin the axial cable channel 19. At the free end of the cable guide of the second end part 4c, a receiving area 22 is formed, to which a plug 23 is attached.

The hub shell 6 includes fasteners 34 for securing spokes, not shown. If necessary, a brake disk 35 is attached to the hub shell 6.

FIG. 2 shows a wheel axle 4, which comprises a central hollow area with an internal thread at both front ends. To fasten the wheel axle 4 to an axle bracket, clamping elements 9 are screwed into the internal threads of the hollow areas. The clamping elements 9 are in the mounted state of the wheel drive 1 from the hollow areas in the longitudinal direction of the wheel axle 4 via the end of the wheel axle 4 to the outside. At the protruding end, the clamping elements comprise, in the longitudinal direction of the wheel axle, compressible clamping surfaces 10 which can be pressed inwards and which press the axle holder, not shown, against abutting end pressing surfaces 11 of the wheel axle 4. The engagement elements 14 ensure the desired anti-rotation. It goes without saying that the wheel axle 4 can also be connected to the axle mount only at one end, in which case the wheel axle 4 only comprises a hollow area on this side and only one tensioning element 9 is used.

3a to 3d show a particularly advantageous designed central part 4a of the wheel axle 4. The axial cable channel 19 and provided for the anti-rotation grooves 17 and the teeth 15 are clearly visible. In order to fix the stator 16 at the desired position along the wheel axis, is a circumferential groove 36th provided, which holds the stator 16 with a Seeger used in the circumferential groove 36 at the desired location. In order to accurately position the second pivot bearing 26 a stop surface 37 is formed. The narrowed ends 38 can be inserted into the end elements 4b and 4c and reinforce the connections to them.

FIGS. 4 a and 4 b show a second end element 4 c with a push-on connection 42, which is adapted to the narrowed end 38 and has a toothing 15. When attaching, make sure that the free area 43 is aligned correctly with the fork. In the receiving area 22, a plug 23 can be fixed with grub screws 44.

FIG. 4c shows the engagement element 14 which is fastened to the end pressing surface 11 by a screw 39, wherein the end pressing surface 11 preferably comprises at least two different fixing means for fastening the engagement element 14 and each fixing device preferably has a stop surface 40 for aligning the engagement element Engagement element 14 and a connecting device, in particular a bore 41 with an internal thread comprises. These two alignment options ensure that the cable guide of the second end element 4c extends in a desired alignment with the fork both for bicycle forks according to IS2000 and for older forks. The two common orientation are mutually rotated by 40 °.

Claims

claims

1. Wheel drive (1) with a wheel axle (4), one on the wheel axle (4) via first rotary bearing (5) rotatably mounted hub shell (6) and in the hub housing (6) arranged drive motor (8), with which the Hub housing (6) about the wheel axle (4) can be set in rotary motion, wherein the wheel drive (1) to be mounted on the Achshalterung (2) of a light vehicle, characterized in that the wheel axle (4) at least at one end end of a central Hollow area comprises, in which a clamping element (9) is used, the clamping element (9) in the assembled state of the wheel drive from the hollow area in the longitudinal direction of the wheel axle (4) beyond the end of the wheel axle (4) projects outwardly and at the projecting end in The tensioner pressing surface (10), the axle holder (2) to a on the axle holder (2) abutment end-pressing surface (1 1) of the wheel axle (4) presses.

2. Wheel drive (1) according to claim 1, characterized in that the wheel axle (4) is designed as a hollow axle, the central hollow portion extends along the entire wheel axle (4), the clamping element (9) in the mounted state of the wheel drive (1 extends through the entire central cavity and protrudes on both sides over the ends of the wheel axle (4) and at both free ends each in the longitudinal direction of the wheel axle (4) against internally compressible tensioner pressing surface (10), wherein the tensioner pressing surfaces (10 ) abut in the assembled state on both sides of the outside of legs of the axle bracket (2) and this on the inside of the legs of the axle bracket (2) adjacent end-pressing surfaces (11)

Press wheel axle (4).

3. wheel drive (1) according to claim 1 or 2, characterized in that the clamping element (9) comprises a pivotable lever (12) with eccentric (13), the eccentric assembly (13) during clamping with the lever (12) the associated tensioner Pressing surface (10) presses against the inside and preferably the clamping element (9) in the assembled state of the wheel drive (1) between the tensioner pressing surfaces (11) and the end-pressing surfaces (11) has a cylindrical portion, wherein the diameter of the cylindrical portion adapted to a passage of the axle holder (2).

4. wheel drive (1) according to one of claims 1 to 3, characterized in that the wheel drive (1) at least one end-pressing surface (11), but preferably at both end-pressing surfaces (1 1), the hollow wheel axle (4 ) comprises an engagement element (14) in the assembled state of the wheel drive (1) a positive engagement on the axle holder (2), preferably on a

Slit of Achshalterung (2), guaranteed, wherein the engagement element (14) relative to the center of the wheel axle (4) radially outside the clamping element (9) is arranged.

5. Wheel drive (1) according to claim 4, characterized in that the engagement element (14) on the end-pressing surface (1 1) is fixed and preferably projecting outwardly therefrom, wherein the end-pressing surface (1 1) preferably at least two various fixing means (39, 40, 41) for fixing the engagement member (14), and each fixing means (39, 40, 41) preferably comprises a stopper surface (40) for aligning the engagement member

(14) and a connecting device, in particular a bore with an internal thread, comprises.

6. wheel drive (1) according to one of claims 1 to 5, characterized in that the wheel axle (4) has a central part (4a) and two at the middle part (4a) attachable end parts (4b, 4c), each with a forehead Pressing surfaces (1 1), wherein the adjoining areas of the central part (4a) and each end part (4b, 4c) have adapted to each other engaging ends, preferably toothings (15) extending in the circumferential direction about the center of the wheel axle (4) ,

7. wheel drive (1) according to claim 6, characterized in that the middle part (4a) of the wheel axle (4) an axial cable channel (19) to one of the subsequent end parts (4c) and this subsequent end part (4c) a weiterfüh- rende Cable guide with an axial channel portion (20) and a relative to the wheel axle (4) radially away leading channel portion (21) and at the free end of the cable guide of the closure part (4c) preferably a receiving area (22) and a plug held therein (23).

8. Wheel drive according to claim 6 or 7, characterized in that the first pivot bearing (5) enclose the mating engagement ends.

9. Wheel drive according to one of claims 1 to 8, characterized in that the drive motor (8) comprises a stator which is arranged rotationally fixed on the wheel axle (4), wherein preferably a positive Verdrehungssicherung- tion is formed, which at the wheel axle ( 4) and on the stator in particular

Pairs of grooves (17) in the longitudinal direction of the wheel axle (4) and inserted in this each comprises a common wedge (18).

10. Wheel drive (1) according to one of claims 1 to 9, characterized in that the drive motor (8) has a rotationally fixed to the wheel axle (4) connected to the stator and a rotating motor part (25) and a planetary gear (27, 28, 30 ), wherein the rotating motor part (25) with at least one second pivot bearing (26) is rotatably mounted on the wheel axle (4) and the wheel axle (4) enclosing outer sprocket (27), the planetary gear (27, 28, 30) has a rotationally fixed on the wheel axle (4) arranged gear part

(29) and rotatably mounted Überertagungszahnräder (28), the hub shell (6) comprises an inner sprocket (30) and the rotation of the outer sprocket (27) via the Übertagungszahnräder (28) on the inner sprocket (30) is transmitted.

11. wheel drive (1) according to claim 10, characterized in that between the wheel axle (4) and the transmission part (29) a floating bearing and a positive rotation lock is formed, the bearing of the transmission gears (28) comprises elastic support members (32) and the twist lock preferably on the wheel axle (4) and on the gear part (29)