Component and assembly for a drive device of an electric bicycle and drive device for an electric bicycle

Abstract

In at least one embodiment, the component (74) has a thread (740) for being screwed to another component (71) with a matching mating thread (710). Furthermore, the component has a receptacle (741) for a clamping element (742). The component also has two sections (743, 744), each forming a portion of the thread. The component is designed such that a force can be exerted on the component via a clamping element held in the receptacle, clamping the two sections against each other.

Description

[0001] A component for a drive unit of an electric bicycle is specified. Furthermore, an assembly for a drive unit of an electric bicycle, a method for assembling a drive unit of an electric bicycle, a drive unit for an electric bicycle, and an electric bicycle are specified.

[0002] Bicycles offer a cost-effective, easy-to-use, and emission-free means of transportation. They have also become widespread as sports and fitness equipment, and certain types have proven particularly suitable for various sporting applications.

[0003] In recent years, enthusiasm for electric bicycles (especially so-called "pedelecs") has grown, despite their relatively high weight and price compared to other bicycles. A key requirement for electric bicycles is providing a reliable and supportive drive system.

[0004] One task to be solved is to provide a component for the drive system of an electric bicycle that contributes to the simple and precise assembly of the drive system. Further tasks to be solved include specifying an assembly with such a component, a method for assembling a corresponding drive system, such a drive system, and an electric bicycle with such a drive system.

[0005] First, the component for a drive device of an electric bicycle is specified.

[0006] In at least one embodiment, the component has a thread for screwing onto another component with a matching mating thread. Furthermore, the component has a receptacle for a clamping element. The component also has two sections, each forming a portion of the thread. The component is designed such that a clamping element held in the receptacle can be used to exert a force on the component, clamping the two sections against each other.

[0007] The present invention is based in particular on the understanding that precise assembly of the drive unit is important for the efficient operation of electric bicycle drive units. Specifically, the individual components of the drive unit should be connected in such a way that, for example, the gear elements of the drive unit are in the correct position and mesh optimally.

[0008] The component described here contributes to the simple yet precise assembly of the drive unit. The screw thread allows the component and the other component to be positioned relative to each other precisely and as desired. By clamping the two sections, each of which forms part of the thread, a locking mechanism can be achieved in any desired relative arrangement of the two components.

[0009] This ensures that the two components remain in the set relative arrangement even after assembly, which benefits the efficient operation of the drive device.

[0010] The component in question is, for example, a housing element or housing part of the drive device. In particular, the component is freely accessible or visible from outside the drive device when it is assembled. For example, the component can be grasped by hand and then screwed to the other component without any tools. The component can be formed in one piece. The component consists, for example, of a metal, especially a light metal such as aluminum or magnesium, or comprises such a material.

[0011] The additional component with the matching mating thread can also be a housing element or housing part of the drive device. This additional component can also be freely accessible from outside the drive device when it is assembled. For example, the additional component can be grasped by hand and then screwed to the component without any tools. This additional component can also be formed in one piece and / or can be made of metal, especially light metals such as aluminum or magnesium.

[0012] The component's thread is, for example, an external thread. Alternatively, it could also be an internal thread. The component is, for example, ring-shaped or cylindrical, particularly hollow. The thread is then located on an outer or inner surface. During tightening, points of the thread move along the surface of a so-called screw cylinder. This is a virtual cylinder. The translational relative movement of the two components during tightening is along, or parallel to, the z-axis of this screw cylinder. The component can be rotationally symmetrical or rotationally symmetrical with respect to the z-axis of the screw cylinder. The z-axis of the screw cylinder is also referred to simply as the "z-axis" in the following. Directions parallel to the z-axis are also referred to as the "z-direction" in the following.

[0013] The receptacle provided in the component is designed to receive a clamping element. This receptacle can be, for example, a slot, a gap, or a hole. It can also be a bore. In particular, the receptacle can be designed to receive an elongated clamping element. This clamping element can be a pin, a screw, a bolt, or a rivet. Alternatively, the clamping element could also be a wedge. For receiving a screw, the receptacle can have an internal thread.

[0014] The two sections of the component each form a section of the thread. Specifically, the two sections are arranged one behind the other in a direction parallel to the z-axis. Each section comprises, for example, at least one, at least two, or at least three thread turns, i.e., complete thread rotations.

[0015] The two sections can be clamped against each other. Two sections are clamped against each other when an internal force within the component attempts to move them relative to each other. Specifically, the two sections are elastically connected, allowing them to be moved relative to each other by the clamping element, with an internal restoring force acting against this relative movement. For example, when clamped against each other using the clamping element, the two sections will move relative to each other by a maximum of 0.5 mm, 0.1 mm, or 0.01 mm. This clamping action can, for example, locally change the thread pitch, which may lead to the bolted connection seizing.

[0016] According to at least one embodiment, the tension between the two sections when the component is screwed together causes the screw connection to jam. For example, in the untensioned, i.e., relaxed, state of the two sections, it is possible to screw the two components together and / or to loosen an existing screw connection between the two components. In the tensioned state of the two sections caused by the tensioning element, a screw connection is jammed, meaning it cannot be loosened, or it is impossible to screw the two components together.

[0017] Alternatively, the component could be designed so that tightening or loosening of a screw connection is only possible after the two sections have been clamped together using the clamping element. Removing and / or loosening the clamping element releases the clamping force, at least partially, thus jamming the screw connection or preventing the two components from being screwed together.

[0018] For example, a thread could be machined into the component during manufacturing. This thread could then be interrupted by a gap. The two sections on either side of the gap could then be plastically deformed relative to each other. In the relaxed state of the two sections relative to each other, it would not be possible to screw the component to another component. Only by clamping the two sections against each other, particularly with the aid of a clamping element held in a fixture, can the original relative arrangement of the two sections be restored—that is, the relative arrangement before the plastic deformation—thus enabling the component to be screwed to the other component. After screwing, the clamping element can then be released or removed, causing the two sections to attempt to return to their relaxed state and thereby jam the screw connection.

[0019] According to at least one embodiment, the component is designed such that the force exerted via the clamping element pushes the two sections away from each other. For example, the two sections are pushed away from each other in a direction parallel to the z-axis.

[0020] Alternatively, it would also be conceivable that the force exerted by the clamping element acts to bring the two sections closer together, for example, to bring them closer together in a direction parallel to the z-axis.

[0021] According to at least one embodiment, the two sections are separated from each other, at least partially, by a gap. The gap can be a groove. The gap extends, for example, circumferentially around the z-axis, or completely around the z-axis. The gap can form a closed loop around the z-axis. However, the gap can also extend only partially, for example, mostly, circumferentially around the z-axis. That is, the gap can lie in the z-direction between the two sections.

[0022] According to at least one embodiment, the gap interrupts the thread. In particular, the gap extends from the surface of the component that encompasses the thread (hereinafter also referred to as the "thread surface") into the component. That is, the opening to the gap is provided in the thread surface of the component.

[0023] The depth of the gap can be perpendicular to the z-axis, and in particular, radial to the z-axis. The gap can penetrate the component completely or terminate within it. The width of the gap, measured, for example, in the z-direction, is greater than the thread pitch. The width of the gap can be at least twice the thread pitch.

[0024] According to at least one embodiment, the two sections are formed integrally. That is, the two sections are part of a single, integrally formed area of ​​the component.

[0025] According to at least one embodiment, the two sections are integrally joined at the bottom of the gap. The bottom of the gap is the deepest part of the gap. In particular, the two sections are integrally joined on one side of the gap opposite the opening. For example, the two sections are integrally joined in a region of the component that is radially further inward along the z-axis than the thread. Alternatively, the opening of the gap could also be radially further inward along the z-axis than the bottom of the gap where the two sections are integrally joined. The bottom of the gap could then extend to the thread and even form part of it.

[0026] In a cross-sectional view, where the section plane for the cross-sectional view includes the z-axis of the screw cylinder, the two sections can be different legs of a "U".

[0027] According to at least one embodiment, the receptacle for the clamping element is a hole, in particular an elongated hole. For example, a longitudinal axis of the hole runs parallel to the z-axis of the screw cylinder. The hole can be recessed radially from the threaded surface of the component with respect to the z-axis. For example, the hole is radially closer to the threaded surface than to the z-axis.

[0028] According to at least one embodiment, the hole is designed to receive a clamping element in the form of a screw or a bolt. In the case of a screw, the surface of the component bounding the hole may have a thread.

[0029] According to at least one embodiment, the receptacle is provided in the first section; in particular, the receptacle is a hole in the first section. For example, the hole extends (especially in the z-direction) through the first section, and in particular, completely through the first section. The receptacle or the hole does not extend through the second section, for example, or even project into the second section.

[0030] According to at least one embodiment, the second section has a stop surface opposite an exit opening of the hole. The stop surface forms, for example, a gap-limiting surface of the second section. The stop surface limits the gap, for example, in the z-direction. The stop surface for the clamping element is, for example, annular and / or flat.

[0031] The exit opening of the recess then borders the gap. In other words, the recess or hole transitions into the gap. The exit opening is located opposite the stop surface, particularly in the z-direction. For example, the longitudinal axis of the hole runs perpendicular to the stop surface.

[0032] According to at least one embodiment, the clamping element is movable along the hole such that one end of the clamping element, for example the end of the screw, protrudes from the exit opening and abuts the stop surface in order to press against the second section and thus clamp the two sections against each other. The movement of the clamping element is, for example, at least partially in the z-direction.

[0033] According to at least one embodiment, the two sections extend around a passage for a pedal shaft. Alternatively or additionally, the thread extends around the passage. In particular, the z-axis of the screw cylinder passes through the passage for the pedal shaft. When the pedal shaft is inserted into the passage, the longitudinal axis or axis of rotation of the pedal shaft can run parallel to the z-axis or even coincide with it.

[0034] The component may have several recesses, which are arranged, for example, around the z-axis or around the feedthrough, and in particular, evenly distributed. For example, at least four or at least six recesses are provided. Each of the recesses is specifically designed to receive a clamping element. All features disclosed in connection with one recess and one clamping element are also disclosed for the other recesses and the associated clamping elements.

[0035] According to at least one embodiment, the hole extends parallel to an insertion direction for the pedal shaft. The insertion direction is, in particular, a direction along or parallel to the z-axis of the screw cylinder.

[0036] Next, the assembly for a drive unit of an electric bicycle is specified.

[0037] In at least one embodiment, the assembly comprises the component according to one of the embodiments described herein. The assembly further comprises a bevel gear that is rotatably mounted relative to the component about an axis of rotation. The thread of the component extends around the axis of rotation, so that when the component is screwed to the other component, the two components rotate relative to each other about the axis of rotation and are displaced in a direction parallel to the axis of rotation. In other words, the z-axis of the screw cylinder defined above runs parallel to or coincides with the axis of rotation.

[0038] Since the assembly includes the component described here, all features disclosed in connection with the component are also disclosed for the assembly and vice versa.

[0039] The bevel gear is, for example, a ring gear. The assembly may also include a bearing for the rotational support of the bevel gear relative to the component. This bearing is typically a radial bearing. A radial bearing is, for example, a rolling bearing, such as a ball bearing. The radial bearing, for example, has an outer ring that abuts the component.

[0040] Furthermore, the assembly can also include a hollow shaft. The bevel gear, for example, runs around this hollow shaft. The hollow shaft forms, for example, the passage for the pedal shaft. The inner ring of the bearing can be adjacent to the hollow shaft. The hollow shaft is coupled to the bevel gear, for example, via a freewheel.

[0041] The hollow shaft can have an interface for a freewheel with the pedal axle. For example, the hollow shaft has an interface for a toothed freewheel. The hollow shaft can also be an output shaft. For example, the hollow shaft has a chainring or chainring spider, or includes an interface for coupling with a chainring or chainring spider.

[0042] The component in question is, in particular, a housing part in which the hollow shaft and / or the bearing and / or the bevel gear are housed.

[0043] Next, the procedure for assembling a drive unit for an electric bicycle will be described.

[0044] In at least one embodiment, the method comprises providing a component according to one of the embodiments described herein. The method further comprises providing another component with a mating thread matching the thread of the component. In a further step, the two components are screwed together via their threads until a desired relative arrangement of the two components is achieved. After screwing, force is applied to the component via a clamping element located in the component's receptacle, thereby clamping the two sections against each other and thus clamping the screw connection between the components.

[0045] Alternatively, force can be applied to the component during the tightening process via a clamping element held in the fixture, thus clamping the two sections against each other. After tightening, the force exerted on the component by the clamping element is reduced or completely removed, thereby locking the bolted joint. With this alternative, the clamping element can, for example, be completely removed from the fixture after tightening.

[0046] According to at least one embodiment, the component is part of an assembly described herein. The further component is part of a further assembly, wherein the further assembly comprises another bevel gear that is rotatably mounted relative to the further component. The two bevel gears are configured to mesh with each other. The desired relative arrangement of the components is one in which the two bevel gears mesh with each other.

[0047] For example, the desired relative arrangement of the components is one in which the two bevel gears are optimally positioned relative to each other. The screw connection allows for very precise adjustment of the relative position between the two bevel gears, and this precise setting can then be maintained by clamping the screw connection using the clamping element.

[0048] Since the component or assembly described herein is used in the procedure described herein, all features disclosed for the component or assembly are also disclosed for the procedure and vice versa.

[0049] The additional bevel gear of the further assembly is, for example, a bevel pinion. The further component is, for example, a housing part in which the further bevel gear is accommodated. The further component can, in particular, be a bottom bracket housing. The further assembly can, for example, include a radial bearing for the rotational support of the further bevel gear. Furthermore, the further assembly can also include other elements, such as a planet carrier for a planetary gear set and associated planet gears, as well as a ring gear of the planetary gear set. The further assembly can also include a thrust bearing for the axial support of the planet carrier. In addition, the further assembly can include a pedal axle. All these elements can be accommodated in the further component and at least partially surrounded by it.

[0050] When joining the two assemblies, the pedal shaft of the second assembly can be pushed through the output shaft of the first assembly.

[0051] According to at least one embodiment of the method, the further assembly is connected to yet another assembly. This step is performed, for example, before the further assembly and the assembly are connected to each other. The yet another assembly comprises, for example, a housing part, such as a motor housing, and an electric motor with a stator, a rotor, and a motor shaft.

[0052] When connecting the two assemblies, the housing parts of the first and second assemblies can be joined together. Furthermore, the motor shaft can be coupled to the planetary gears.

[0053] Next, the drive system for an electric bicycle is described. The drive system can be assembled or manufactured using the method described herein. Therefore, all features disclosed for the method are also disclosed for the drive system, and vice versa.

[0054] In at least one embodiment, the drive device comprises a component according to one of the embodiments described herein. Furthermore, the drive device comprises a bevel gear that is rotatably mounted relative to the component about an axis of rotation. The drive device also comprises another component with a thread and another bevel gear that is rotatably mounted relative to the other component about a further axis of rotation. This further axis of rotation extends transversely, in particular perpendicularly, to the first axis of rotation. The two components are screwed together via the threads, the two bevel gears mesh, and the screw connection between the components is clamped.

[0055] According to at least one embodiment, a clamping element is included in the component's receptacle, clamping the two sections against each other. For example, the drive device or the component comprises at least three, four, or five receptacles, each containing a clamping element, thereby clamping the two sections against each other.

[0056] Next, the electric bicycle is described. The electric bicycle includes a drive device as described here. In particular, during operation of the electric bicycle, the bevel gear and / or the other bevel gear are driven by an electric motor.

[0057] The following sections provide a more detailed explanation of a component, assembly, method, drive device, and electric bicycle described herein, with reference to the drawings and exemplary embodiments. Identical reference numerals indicate identical elements in the individual figures. If elements or components function identically in different figures, their descriptions are not repeated for each subsequent figure. For clarity, elements may not be labeled with corresponding reference numerals in all illustrations.

[0058] They show: Fig. 1 an embodiment of the electric bicycle, Fig. 2 an embodiment of the component, Fig. 3 an embodiment of the drive device, Fig. 4 and Fig. 5 another embodiment of the component, Fig. 6 and Fig. 7 different positions in an embodiment of the method for assembling a drive device, Fig. 8, Fig. 9 and Fig. 11 Examples of different assemblies for a drive device, Fig. 10 and Fig. 12 positions in a further embodiment of the method for assembling a drive device.

[0059] Fig. Figure 1 schematically shows an electric bicycle 200 with a bicycle frame 110, which has a lower frame section 120. This forms a down tube. The lower frame section 120 extends towards a bottom bracket of the electric bicycle 200, the bottom bracket comprising a pedal axle 90. The pedal axle 90 is part of a drive unit 100 installed in the bicycle.

[0060] Fig. Figure 2 shows a first embodiment of component 74 for a drive device. Component 74 is, for example, a housing part for the drive device 100, such as a cover. Component 74 can be made of metal, for example, a single piece of aluminum. Component 74 is hollow and cylindrical. For clarity, only one quarter of component 74 is shown here. In reality, however, component 74 extends completely around the z-axis P.

[0061] On an outer surface, component 74 has a thread 740, which is designed for engagement and screwing with a mating thread of another component. The z-axis of the screw cylinder is the z-axis P shown. This also corresponds, for example, to the axis of symmetry of the hollow cylindrical component 74.

[0062] Component 74 comprises a first section 743 and a second section 744, which are arranged one behind the other in a direction parallel to the z-axis and separated from each other in this direction by a gap 746. The gap 746 is filled with an elastically deformable material, for example, an elastomer. This allows the two sections 743 and 744 to be displaced along the z-axis P and clamped against each other.

[0063] The two sections 743 and 744 each form part of the external thread 740. When component 74 is screwed to the other component, component 74 is rotated about the z-axis P and simultaneously translated along the z-axis P.

[0064] Component 74 has a recess 741 in the form of an elongated hole. The hole 741 extends parallel to the z-axis P through the first section 743, across the gap 746, and into the second section 744. The hole 741 is designed to receive a clamping element in the form of a pin, bolt, or rivet. By pressing in the clamping element, the two sections 743 and 744 can be clamped against each other against the restoring force of the elastic material in the gap. If component 74 is previously screwed to another component, the subsequent clamping action can lock and secure the screw connection between component 74 and the other component.

[0065] As in the Fig. As can be seen in Figure 2, component 74 is also surrounded by a passage 745. The z-axis P extends through this passage 745. The passage is designed, for example, for inserting a pedal shaft. This will be explained in more detail in connection with the following figures.

[0066] Fig. Figure 3 shows an embodiment of the drive device 100 in a cross-sectional view. The drive device 100 comprises a housing 7 with three interconnected components 70, 71, 74 in the form of housing parts 70, 71, 74. Housing part 70 forms a motor housing in which an electric motor 1 is accommodated. Housing part 71 forms a bottom bracket housing in which, among other things, a planetary gear 2 is accommodated. The motor housing 70 and the bottom bracket housing 71 are connected to each other via a sealing sleeve 72. Housing part 74 forms an output-side cover that is screwed onto the bottom bracket housing 71.

[0067] The electric motor 1 comprises a stator 12 and a rotor 11. The electric motor 1 is an internal rotor motor. During operation, the rotor 11 rotates relative to the stator 12, or rather to the housing 7, about an axis of rotation A. The rotor 11 is coupled to a motor shaft 10 and, during operation, also sets the shaft into rotation about the axis of rotation A. The axis of rotation A passes through the motor shaft 10. The motor shaft 10 is made, for example, of stainless steel or case-hardened steel. The electric motor 1 is mounted in the housing 7 by means of motor bearings 16.

[0068] The motor shaft 10 projects axially out of the rotor 11 and into the planet carrier 20 of the planetary gear 2. In the opposite axial direction, a magnet 14 is arranged at the end of the motor shaft 10, spaced apart from the motor shaft 10 by an adapter 15. The adapter 15 is made of aluminum, for example, and is intended to reduce the influence of the steel motor shaft 10 on the magnetic field generated by the magnet 14. The drive device 100 further includes a sensor (not shown) that detects the magnetic field of the magnet 14 and thereby qualitatively and quantitatively determines the position of the motor shaft 10.

[0069] The planetary gear 2, which forms a first gear stage of the drive device 100, comprises the planet carrier 20, three planet gears 21, a sun gear 26 and a ring gear 27. In the Fig. Figure 3 shows a cross-sectional view of a first planet gear 21, namely the one located above the axis of rotation A, while another planet gear 21 is shown in a top view. The planet gears 21 are rotatably mounted on the planet carrier 20. The planet carrier 20 is also rotatably mounted about the axis of rotation A by means of two rolling bearings 4, 5. In this case, the planet carrier 20 has bushings 25 that are inserted through holes in the planet gears 21.

[0070] The sun gear 26 for the planetary gear set 2 is integrated into the motor shaft 10; that is, the motor shaft 10 and the sun gear 26 are formed as a single piece. Specifically, the teeth for the sun gear 26 are formed in the motor shaft 10 by means of a forming process, for example, a rolling process. This means that the teeth for the sun gear 26 are manufactured without milling, as can be seen from the absence of milling marks. The teeth of the sun gear 26 are helical, meaning that the teeth are not parallel, but rather angled to or helically around the axis of rotation A.

[0071] The teeth of the sun gear 26 engage with corresponding helical teeth of the planet gears 21. Rotation of the motor shaft 10 sets the planet gears 21 into rotation, which in turn causes the planet carrier 20 to rotate around the axis of rotation A. The planet gears 21 roll against the stationary ring gear 27. The ring gear 27 is fixed, for example, to the housing 7 and therefore does not rotate relative to the housing 7 during operation.

[0072] The use of a forming process in the manufacturing of the sun gear 26's teeth results in a particularly smooth surface. The teeth of the planet gears 21, for example, are made of plastic. The smooth surface of the sun gear 26 is especially advantageous when using plastic for the planet gears 21, as it minimizes wear. Planet gears made entirely or partially of plastic tolerate larger manufacturing tolerances and are less susceptible to tilting relative to the planet carrier 20.

[0073] In fact, a tilting moment acts on the planet gears 21, which tends to tilt them relative to the planet carrier 20. This tilting moment results largely from the use of helical gearing. However, helical gearing is advantageous with regard to high power transmission and low noise generation.

[0074] To minimize and effectively counteract tilting of the planet gears 21 relative to the planet carrier 20, each planet gear 21 is rotatably mounted on the planet carrier 20 by means of a needle bearing 22. The needle- or cylindrical-shaped rolling elements 24 of the needle bearing 22 roll on the bushings 25 on one side and on sleeves 23 on the other. The bushings 25 and the sleeves 23 are made of metal, for example. The sleeves 23 are part of the planet gears 21 and are encased or overmolded with plastic, with the teeth of the planet gears 21 being formed from this plastic. By reducing the relative tilting between the planet gears 21 and the planet carrier 20 through the use of the needle bearings 22, the wear of the drive device 100 can be reduced and its performance increased.

[0075] The planet carrier 20 has a recess at one axial end facing away from the motor 1. The axis of rotation A passes through this recess. The planet carrier 20 has an internal thread in the area of ​​the recess. A first bevel gear 30, namely a bevel pinion, of a bevel gear stage 3 is screwed into this internal thread. The bevel gear stage 3 forms a second gear stage of the drive device 100. The first bevel gear 30 has a cylindrical section with an external thread and a conical section with external teeth. The cylindrical section is screwed into the recess of the planet carrier 23, thereby fixing the first bevel gear 30 to the planet carrier 23 and making it immovable relative to the planet carrier 20, i.e., rotationally fixed to it. The first bevel gear 30 is precisely aligned relative to the planet carrier 20 by means of a centering collar.The cone-shaped section protrudes axially, away from the electric motor 1, from the planet carrier 20.

[0076] The first bevel gear 30 has a recess that is open towards the electric motor 1 and into which the motor shaft 10 is guided. The motor shaft 10 can rotate freely within this recess. Unlike in the Fig. As shown in Figure 3, the motor shaft 10 could be rotatably mounted within the recess by means of a bearing.

[0077] The section of the motor shaft 10 projecting into the recess of the bevel gear 30 is free of teeth. This section forms, for example, an interface for a so-called "stand-alone" test of the electric motor 1, that is, a test in its uninstalled state.

[0078] In operation, the planet carrier 20 and the first bevel gear 30 rotate together around the axis of rotation A. The bevel gear stage 3 has a second bevel gear 31 in the form of a ring gear. The second bevel gear 31 is mounted to rotate around a pedal axle P, the pedal axle P being perpendicular to the axis of rotation A. Bevel gear stage 3 is therefore a 90° bevel gear stage.

[0079] The second bevel gear 31 is coupled via a freewheel 81 to an output shaft 80 in the form of a hollow shaft. The output shaft 80 is part of an output 8. The output 8 also includes, for example, a chainring and / or a chainring spider (not shown), which are rotationally fixed to the output shaft 80. Alternatively, the output shaft 80 can also simply have an interface for a rotationally fixed coupling with the chainring or the chainring spider.

[0080] A pedal shaft 90 extends through the hollow-shafted output shaft 80. The pedal shaft 90 is coupled to the output shaft 80. Both the pedal shaft 90 and the output shaft 80 are rotatably mounted by radial bearings 60, 61, the so-called main bearings 60, 61. When the rider of the e-bike pedals, the pedal shaft 90 is set into rotation about the pedal axis P, thereby engaging the output shaft 80 via a freewheel mechanism. The electric motor 1 then exerts a torque on the output shaft 80, assisting the rider, via the planetary gear 2 and the bevel gear stage 3. The drive device 100 shown is an orthogonal drive.

[0081] By using a bevel gear stage 3 directly coupled to the planet carrier 20, i.e., without any further, intermediate gear stage, the drive device 100 can be designed to be particularly compact and simultaneously provides an efficient speed reduction from the electric motor 1 to the output 8. However, the direct coupling between the planet carrier 20 and the bevel gear stage 3 also results in the bevel gear stage 3 exerting an axial force, a radial force, and an azimuthal force on the planet carrier 20 during operation of the drive device 100. These forces attempt to push the planet carrier 20 towards the electric motor 1 and simultaneously tilt the planet carrier 20.

[0082] To efficiently absorb the radial forces acting upon it, the planet carrier 20 is mounted in the housing 7 via a large radial bearing 4. The radial bearing 4 has, for example, an inner diameter of 5 cm. The radial bearing 4 is supported by the planet carrier 20.

[0083] The axial forces that occur are absorbed by a thrust bearing 5. In particular, the tilting moment results in a large axial load on the thrust bearing 5. The thrust bearing 5 also has a large diameter. Here, the thrust bearing 5 is arranged at the outer edge or outer circumference of the planet carrier 20, radially as far away as possible from the axis of rotation A. In addition, elongated rolling elements, such as cylinders or cones, are used as the rolling elements 50 of the thrust bearing 5, which distributes the load over a larger area.

[0084] To minimize tilting of the planet carrier 20, the axial play for the planet carrier 20 between the radial bearing 4 and the thrust bearing 5 is selected to be particularly small, for example, a maximum of 0.1 mm. This is achieved, among other things, by a small tolerance chain in the axial direction. The small tolerance chain is implemented as follows: One thrust washer 51 of the thrust bearing 5, against which the rolling elements 52 roll, is arranged in the axial direction directly opposite a support element, namely a radially extending part of the motor housing 70. The other thrust washer 52 of the thrust bearing 5 is arranged in the axial direction directly opposite the planet carrier 20.Furthermore, the inner ring 42 of the radial bearing 4, on which the rolling elements 40 of the radial bearing 4 roll, is arranged axially directly opposite the planet carrier 20, and the outer ring 41 of the radial bearing 4 is arranged axially directly opposite another support element, namely a part of the bottom bracket housing 71. The motor housing 70 and the bottom bracket housing 71 are axially immovably connected to each other. The elements directly opposite each other axially either abut each other or are separated from each other in the axial direction by at most narrow gaps. In particular, the sum of the axial distances between the aforementioned directly opposite elements is less than 0.1 mm.

[0085] With the drive device 100 installed and the motor running, the planet carrier 20 is pressed axially towards the electric motor 1. The planet carrier 20 is then supported axially directly against the thrust washer 52, and the thrust washer 51 is supported axially directly against the motor housing 70. The aforementioned small axial distances ensure that the planet carrier 20 hardly tilts despite the strong tilting moment.

[0086] Another measure to reduce tilting of the planet carrier 20 is to ensure minimal radial play between the planet carrier 20 and the first bevel gear 30. For this purpose, the first bevel gear 30 is rigidly connected to the planet carrier 20. The radial play of the planet carrier 20 is kept low because the radial bearing 4 used for the radial support of the planet carrier 20, which is arranged radially between the planet carrier 20 and the housing 7, has its inner ring 42 in contact with the planet carrier 20 and its outer ring 41 with the housing 7. No intermediate elements are used between the radial bearing 4 and the housing 7, as these could increase the radial play of the planet carrier 20 or the first bevel gear 30. In other words, by using fewer elements in the radial tolerance chain, the radial play of the first bevel gear 30 and the planet carrier 20 is kept low.Tilting the planetary carrier 20 is therefore only possible to a limited extent.

[0087] Overall, the use of the described radial bearing 4 and the described axial bearing 5 helps to counteract tilting of the planet carrier 20 and to efficiently absorb the acting forces. This results in particularly high performance of the drive device 100 with simultaneously low wear.

[0088] Performance is further enhanced by the precise alignment of the bevel gears 30 and 31 relative to each other. This is achieved, firstly, by the previously described low-backlash bearing arrangement of the planet carrier 20 and the first bevel gear 30, and secondly, by the low-backlash bearing arrangement of the second bevel gear 31. For this purpose, the second bevel gear 31 is rigidly connected to the output shaft 80. The output shaft 80, in turn, is rotatably mounted about the axis of rotation P via the radial bearing 60, which is in direct contact with the output shaft 80 on one side and with the cover 74 on the other. The cover 74 is rigidly connected to the bottom bracket shell 71.Here too, to reduce the play of the second bevel gear 31 in the axial direction, parallel to the axis of rotation A, a rotatable bearing of the second bevel gear 31 around the axis of rotation P with few moving elements between the housing 7 and the second bevel gear 31 is implemented.

[0089] The fixed connection between the housing parts 71 and 74 is a screw connection. For this screw connection, the bottom bracket housing 71 and the cover 74 have threads 710 and 740, respectively, which interlock. These threads 710 and 740 extend around the axis of rotation P of the pedal axle 90. The relative arrangement between the housing parts 71 and 74 is secured by means of clamping elements 742. In this case, the clamping elements 742 are screws that are screwed into receptacles 741 of the housing part 74. Specifically, the housing part 74 has two annular sections 743 and 744, which, in the illustrated cross-sectional view, are formed by a U-shaped area of ​​the third housing part 74, i.e., they are spaced apart from each other by a gap parallel to the axis of rotation P. The two sections 743 and 744 each form part of the external thread 740 of the housing part 74.The screwed-in screws 742 push the second section 744 away from the first section 743 with a longitudinal end, causing the screw connection to jam between the housing parts 71, 74 and thus fixing them in their relative arrangement to each other.

[0090] The second bevel gear 31 is restricted in its movement relative to the third housing element 74 in a direction parallel to the axis of rotation P by means of stop surfaces. The screw connection between the housing parts 71 and 74 therefore allows the second bevel gear 31 to be positioned particularly precisely along the axis of rotation P. The tightening of the screw connection then ensures a particularly stable position of the second bevel gear 31 in the direction of the axis of rotation P. Overall, the bevel gears 30 and 31 are thus aligned with particular precision relative to each other, which benefits the performance of the entire drive device 100.

[0091] The one in Fig. 3. Housing part 74 shown could be as in the Fig. 2 described, or as the embodiments of the component described below.

[0092] Fig. Figure 4 shows an embodiment of the component or housing part 74 in a perspective view. Fig. Figure 5 shows part of component 74 of the Fig. Figure 4 shows a sectional view. Here too, component 74 comprises two sections 743 and 744, each forming a portion of the external thread. The two sections 743 and 744 are separated from each other by a gap 746 in a direction parallel to the z-axis P. The gap 746 extends azimuthally around the z-axis P completely. With respect to the z-axis P, the gap 746 extends radially inward from the external thread 740 in the direction of the z-axis P, but does not completely penetrate component 74.

[0093] Component 74 has several recesses 741 for receiving a clamping element each (see Fig. 4) The receptacles 741 are elongated holes extending parallel to the z-axis P. The walls of component 74 that bound the holes 741 each have a thread (see Fig. 5) The holes 741 extend through the first section 743 and transition into the gap 746 at an exit opening. The exit openings are located in a direction parallel to the z-axis P opposite a stop surface. The stop surface is formed by the second section 744.

[0094] In the Fig. 6 is a position in an embodiment of the method for assembling a drive device, for example the drive device 100 of the Fig. 3, shown. Here is component 74 of the Fig. 6 is screwed into another component 71. For this purpose, the other component 71 has a mating thread 710 corresponding to the thread 740. Component 74 is, for example, the cover of the Fig. 3 and at component 71 around the bottom bracket housing of the Fig. 3.

[0095] In the Fig. Figure 7 shows another position in the process. Here, a clamping element 742 in the form of a screw is screwed into the receptacle 741. The screw 742 is screwed in to such an extent that a longitudinal end of the screw 742 protrudes from the exit opening, bridges the gap 746, and abuts the stop surface. By tightening the screw, a force can be exerted on the component 74, which pushes the sections 743 and 744 apart and clamps them against each other. This clamps and secures the screw connection between the two components 71 and 74.

[0096] Fig. Figure 8 shows an embodiment of the further assembly 101 for the drive device of the Fig. 3. Assembly 101 comprises the bottom bracket housing 71, the planet carrier 20, and the first bevel gear 30, which are rotationally fixed to one another and are rotatably mounted by means of the radial bearing 4 supported by the planet carrier 20. Assembly 101 further comprises the planet gears 21, which are rotatably mounted on the planet carrier 20 by means of the needle bearings 22. The axial bearing 5 is located on the side of the planet carrier 20 facing away from the first bevel gear 30. The pedal axle 90 is also inserted through the bottom bracket housing 71. The bottom bracket housing 71 is, for example, made of metal. Here, the bottom bracket housing 71 is formed in one piece and encloses both the pedal axle 90 in the direction around the pedal axis P and the planet carrier 20 in the direction around the axis of rotation A.

[0097] Fig. Figure 9 shows an embodiment of the further assembly 102 for the drive device 100 of the Fig. 3. The assembly 102 comprises the motor housing 70, in which the electric motor 1 with the associated motor shaft 10 is accommodated.

[0098] For the assembly of the drive device 200 of the Fig. 3. First, assembly 102 is plugged together with assembly 101. The resulting device is in Fig. Figure 10 shows the assembly process. During assembly, the motor shaft 10 is pushed through the planet carrier 20 and into the receptacle of the first bevel gear 30. The thrust washer 51 is also positioned axially directly opposite a radially extending section of the motor housing 70. The dimensions of the individual elements are selected such that no or only small air gaps occur in the axial direction between the housing sections, against which the bearings 4 and 5 can be axially supported.

[0099] Fig. Figure 11 shows an embodiment of the assembly 104 for the assembly of the drive device 100 of the Fig. 3. Assembly 104 comprises the previously described component 74 or housing part 74 (see, for example, Fig. 4 and Fig. 5) The clamping elements 742, in the form of screws, are already inserted into the receptacles 741 of component 74, but only to the extent that sections 743 and 744 are not yet clamped against each other. The assembly 104 further comprises the bevel gear 31, the output shaft 80, and the radial bearing 60. The bevel gear 31 and the output shaft 80 are rotatably mounted about the axis of rotation P via the radial bearing 60.

[0100] For the assembly of the drive device, assembly group 104 of the Fig. 11 on the device of the Fig. 10 screwed on (see Fig.12) The pedal shaft 90 is pushed through the opening 745 in the housing part 74. The housing parts 74 and 71 are screwed together until the positioning of the bevel gears 30 and 31 parallel to the axis of rotation P is adjusted as desired. The screws 742 are then tightened, which clamps the sections 743 and 744 against each other and thus secures the screw connection between the housing part 74 and the housing part 71. This fixes the bevel gears 30 and 31 in their relative position parallel to the axis of rotation P. Reference symbol list 1 electric motor 2 planetary gears 3 bevel gear stage 4 radial bearings 5 axial bearings 7 cases 8 Drive 10 Motor shaft 11 Rotor 12 Stator 14 Magnet 15 adapters for magnets 16 engine mounts 20 planetary carriers 21 planetary gear 22 needle bearings 23 Outer sleeve 24 rolling elements 25 Bushing / Bolt 26 sun wheel 27 Ring gear 30 first bevel gear / pinion 31 second bevel gear / ring gear 40 rolling elements 41 Outer ring 42 inner ring 50 rolling elements 51 Thrust washer 52 Thrust washer 60 radial bearings 61 radial bearings 70 Engine housings 71 Bottom bracket shell 72 Sealing sleeve 74 Cover / Component 80 Output shaft 81 Freewheel 90 Pedal shaft 100 drive device 101 Assembly 102 Assembly 104 Assembly 110 bicycle frames 120 down tube 200 electric bicycle 710 thread 740 thread 741 recording 742 Fixing element / screw 743 first section 744 second section 745 Implementation A axis of rotation P Pedal axle / rotation axle 746 gap

Claims

[1] Component (74) for a drive device (100) of an electric bicycle (200), comprising - a thread (740) to be screwed to another component (71) with a matching mating thread (710), - a receptacle (741) for a clamping element (742), - two sections (743, 744) each forming a region of the thread (740), wherein - the component (74) is arranged such that a force can be exerted on the component (74) via a clamping element (742) received in the receptacle (741), which clamps the two sections (743, 744) against each other. [2] Component (74) according to claim 1, wherein - the tension between the two sections (743, 744) in the screwed state of the component (74) leads to a jamming of the screw connection. [3] Component (74) according to claim 1 or 2, wherein - the component (74) is arranged such that the force that can be exerted via the clamping element (742) pushes the two sections (743, 744) away from each other. [4] Component (74) according to one of the preceding claims, wherein - the two sections (743, 744) are separated from each other at least section by a gap (746), - the gap (746) interrupts the thread (740). [5] Component (74) according to claim 4, wherein - the two sections (743, 744) are formed in one piece and are joined in one piece at the bottom of the gap (746). [6] Component (74) according to one of the preceding claims, wherein - the receptacle (741) is a hole through the first section (743) which is designed to receive a clamping element (421) in the form of a screw or bolt, - the second section (744) has a stop surface opposite an exit opening of the hole (741), - the clamping element (742) is movable along the hole (741) such that one end of the clamping element (742) protrudes from the exit opening and abuts the stop surface in order to press against the second section (744) and thus clamp the two sections (744, 744) against each other. [7] Component (74) according to one of the preceding claims, wherein - the two sections (743, 744) and the thread (740) extend around a passage (745) for a pedal shaft (90). [8] Component (74) according to claim 7 with reference to claim 6, - wherein the hole (741) extends parallel to an insertion direction for the pedal shaft (90). [9] Assembly (104) for a drive device (100) of an electric bicycle (200), comprising - the component (74) according to one of the preceding claims, - a bevel gear (31) which is mounted to rotate about an axis of rotation (P) relative to the component (74), - wherein the thread (740) of the component (74) runs around the axis of rotation (P), so that when the component (74) is screwed to the other component (71), the two components (74, 71) are rotated relative to each other around the axis of rotation (P) and are moved parallel to the axis of rotation (P) relative to each other. [10] Method for assembling a drive device (100) of an electric bicycle (200), comprising the steps - Providing a component (74) according to any one of claims 1 to 8; - Providing another component (71) with a mating thread (710) matching the thread (740) of the component (74); - Screwing the two components (71, 74) together via the threads (710, 740) to a desired relative arrangement of the two components (71, 74); wherein - after screwing, force is exerted on the component (74) via a clamping element (742) received in the receptacle (741), thereby clamping the two sections (743, 744) against each other and thus clamping the screw connection between the components (74, 71), or - during screwing, force is exerted on the component (74) via a clamping element (742) received in the receptacle (741), thereby clamping the two sections (743, 744) against each other, and after screwing, the force exerted by the clamping element (742) on the component (74) is at least reduced, thereby clamping the screw connection. [11] Method according to claim 10, wherein - the component (74) is part of an assembly (104) according to claim 9, - the further component (71) is part of a further assembly (101), wherein the further assembly (101) comprises a further bevel gear (30) which is rotatably mounted relative to the further component (71), - the two bevel gears (30, 31) are arranged to mesh with each other, and - the desired relative arrangement of the components (74, 71) is an arrangement in which the two bevel gears (30, 31) mesh together. [12] Drive device (100) for an electric bicycle (200), comprising - a component (74) according to one of claims 1 to 8, - a bevel gear (31) which is mounted to rotate about an axis of rotation (P) relative to the component (74), - another component (71) with a thread (710), - another bevel gear (30) which is mounted to rotate relative to the other component (71) about a further axis of rotation (A) which runs transversely to the axis of rotation (P), - the two components (71, 74) are screwed together via the threads (710, 740), the two bevel gears (30, 31) mesh together and the screw connection between the components (74, 71) is clamped. [13] Drive device (100) according to claim 12, wherein - in the recording (741) a tensioning element (742) is recorded, which tensions the two sections (743, 744) against each other. [14] Electric bicycle (200) with a drive device (100) according to one of claims 12 or 13.

Images