Eccentric gear for a muscle-powered vehicle

Abstract

The invention relates to an eccentric drive (1) for a muscle-powered vehicle (2), comprising an eccentric wheel carrier (3) with several carrier bolts (4) and at least one planetary roller (5, 5.1, 5.2) rotatably arranged on each carrier bolt (4), at least one eccentric wheel (6.1, 6.2) with several drive openings (7) and a central eccentric receiving opening (8), a ring gear toothing (9) and an eccentric shaft (10), wherein each carrier bolt (4) is guided through a drive opening (7) on the at least one eccentric wheel (6.1, 6.2) and the respective planetary roller (5, 5.1, 5.2) comes into contact in the respective drive opening (7), wherein the eccentric shaft (10) engages in the central eccentric receiving opening (8) and the at least one eccentric wheel (6.1, 6.2) engages in the ring gear toothing. (9) proceeds, whereby either the respective carrying opening (7) or the respective planetary roller (5, 5.1, 5.2) is at least partially convex and the other of these two components is at least partially conically tapered, wherein at least one preload spring (11) is arranged on the respective planetary roller (5, 5.1, 5.2) and is configured to load the respective planetary roller (5, 5.1, 5.2) in the direction of the conical tapering.

Description

The invention relates to an eccentric gear for a muscle-powered vehicle. The invention further relates to a muscle-driven vehicle having such an eccentric gear.For example, DE 10 2021 119 145 A1 discloses a drive arrangement for a muscle-driven vehicle, having a generator module for generating electrical energy for a drive module. The generator module has a generator that can be driven by a vehicle user by pedaling force and a transmission device for transmitting the pedaling force to the generator. The drive module is used to generate an electric drive torque, wherein the drive module has an electric motor which can be connected by drive technology to a drive wheel of the vehicle and a further transmission device for transmitting the electric drive torque to the drive wheel. The transmission device of the generator module and the further transmission device of the drive module are each designed essentially identically as an eccentric transmission. The eccentric gear has an eccentric wheel carrier with a plurality of carrier bolts, at least one eccentric wheel with a plurality of driver openings and a central eccentric receiving opening, a ring gear section and an eccentric shaft. In each case, a carrier bolt engages in one of the driver openings, the eccentric shaft engages in the central eccentric receiving opening, and the eccentric wheel runs in the ring gear section.DE 10 2021 129 370 A1 describes an eccentric gearing for a generator module of a vehicle. The eccentric gear comprises an eccentric wheel carrier rotatable about the axially extending main axis. This has a plurality of carrier bolts which are arranged in the same direction as the main axis. The at least one eccentric wheel has a plurality of driver openings, in each of which a carrier bolt engages, on which a planetary sleeve is mounted. The eccentric gear comprises a plurality of guide devices, by means of which the planetary sleeves are axially guided.The object of the present invention is to provide an improved eccentric gear for a muscle-driven vehicle, wherein in particular oscillations and vibrations during operation of the eccentric gear are to be reduced.The object is achieved by the subject matter of claim 1.An eccentric gear according to the invention for a muscle-driven vehicle comprises an eccentric wheel carrier with a plurality of carrier bolts and at least one planetary roller arranged rotatably on the respective carrier bolt, at least one eccentric wheel with a plurality of driver openings and a central eccentric receiving opening, a ring gear toothing and an eccentric shaft, wherein in each case one carrier bolt is guided through in each case one driver opening on the at least one eccentric wheel and the respective planetary roller comes to bear in the respective driver opening, wherein the eccentric shaft engages in the central eccentric receiving opening and the at least one eccentric wheel runs in the ring gear toothing, wherein either the respective driver opening or the respective planetary roller is at least partially designed in a spherical manner and the respective other of these two components is at least partially designed in a conically tapering manner, wherein at least one prestressing spring is arranged on the respective planetary roller and is designed to load the respective planetary roller in the direction of the conical tapering.The respective planetary roller is therefore loaded, in particular pressed, in the direction of the conical taper by the at least one prestressing spring in order, during operation of the eccentric gear mechanism, to ensure permanent contact between the respective planetary roller and the respective driver opening in the respective eccentric wheel and thereby improve the NVH behavior. "NVH" stands for "noise, vibration,", that is to say "noise, vibration, roughness", wherein the NVH behavior collectively describes the audible and / or perceptible vibrations and vibrations on vehicles and machines. By loading the respective planetary roller by means of the prestressing spring and the combination of a spherical and a conical geometry on the contact partners planetary roller and entrainment opening, it can be ensured that, despite manufacturing and assembly tolerances, the contact between the respective planetary roller and the respective entrainment opening permanently exists, so that oscillations and vibrations during operation of the eccentric gearing are reduced or avoided.The conical tapering creates a geometry on the inner circumferential surface of the respective driver opening or on the outer circumferential surface of the respective planetary roller, which geometry has a first diameter and a second diameter, wherein the second diameter is smaller than the first diameter. Thus, a load in the direction of the conical tapering is to be understood as a load in the direction of the second, i.e. the smaller diameter. In particular, this loading takes place in the direction of the conical narrowing substantially parallel to the axis of rotation of the respective planetary roller. In particular, the axis of rotation of the respective planetary roller is formed parallel to the central axis of the eccentric wheel carrier.For example, the respective driver opening is at least partially or completely spherical and the respective planetary roller is at least partially or completely conically tapered. Alternatively, the respective entrainment opening is formed at least partially or completely conically tapering and the respective planetary roller is formed at least partially or completely spherically. A spherical configuration is to be understood as meaning essentially a convex geometry on an inner circumferential surface of the respective driver opening or on an outer circumferential surface of the respective planetary roller.According to a preferred embodiment, an outer circumferential surface of the respective planetary roller is at least partially or completely spherical, wherein the respective entrainment opening is formed as a conical bore in the respective eccentric wheel. Consequently, at least a part or the entire outer circumferential surface or circumferential surface of the respective planetary roller is designed to be spherical, wherein at least a part or the entire inner circumferential surface of the respective entrainment opening is designed to be conical. A conical bore has a frustoconical volume.According to a preferred embodiment, exactly one first and one second planetary roller are arranged on each carrier bolt, wherein the biasing spring is arranged axially between the two planetary rollers on the respective carrier bolt. The biasing spring is supported axially on the two planetary rollers and presses them apart. In particular, the biasing spring between the two planetary rollers is designed as a corrugated spring. The corrugated spring is particularly compact and requires less installation space compared to a helical compression spring.According to a preferred embodiment, the respective first planetary roller on each carrier bolt is arranged in a respective conical entrainment opening on a first eccentric wheel, wherein the respective second planetary roller on each carrier bolt is arranged in a respective conical entrainment opening on a second eccentric wheel, wherein the two eccentric wheels are mounted on the eccentric shaft rotated by 180° with respect to one another. The rotation of the two eccentric wheels takes place with respect to the central axis of the eccentric wheel carrier. In particular, the conicityes of the entrainment openings in the first eccentric wheel are embodied opposite to the conicityes of the entrainment openings in the second eccentric wheel. The entrainment opening is formed so as to taper from the inside to the outside, wherein the prestressing spring presses the planetary rollers apart, that is to say outwards in the direction of the conical taper, that is to say towards the smaller diameter. The inside is where the eccentric wheels are arranged adjacent to one another. Furthermore, in the present case, the prestressing spring is also arranged on the inside between the two planetary rollers.According to an alternative embodiment, exactly one planetary roller is arranged on each carrier bolt, wherein exactly one biasing spring presses the planetary roller into the conical entrainment opening. For this embodiment, significantly larger prestressing springs can be used, since not two planetary rollers are provided for each carrier bolt, but only one planetary roller is provided for each eccentric wheel, so that half of the planetary rollers are used for each eccentric wheel. In particular, the respective prestressing spring is designed as a helical compression spring. Although the helical compression spring requires more installation space than a corrugated spring, it has the advantage of a greater spring stroke.According to a preferred embodiment, the planetary rollers are arranged alternately in the circumferential direction in a respective conical entrainment opening on a first eccentric wheel and in a respective conical entrainment opening on a second eccentric wheel. In the circumferential direction refers to the central axis of the eccentric wheel carrier.According to a preferred embodiment, the conicityes of all the driver openings in the first eccentric wheel have the same orientation, wherein the conicityes of all the driver openings in the second eccentric wheel have the same orientation. All planetary rollers per eccentric wheel are pressed in the same direction by the respective prestressing spring. Alternatively, it is also conceivable that, in the case of an even number of planetary rollers per eccentric wheel, for example in the case of four planetary rollers per eccentric wheel, exactly half of the planetary rollers, that is to say two planetary rollers, are pressed in a first direction and the other half of the planetary rollers, preferably alternately, are pressed in the second direction arranged opposite thereto. The pressure on the respective planetary roller is exerted by the at least one biasing spring.According to a preferred embodiment, the conicityes of the entrainment openings in the first eccentric wheel are embodied opposite to the conicityes of the entrainment openings in the second eccentric wheel. The respective diameter of the conical entrainment openings in the respective eccentric wheel is reduced from the inside to the outside, wherein the inside is where the eccentric wheels are arranged adjacent to one another.A muscle-driven vehicle according to the invention has an eccentric gearing according to the invention. In particular, the muscle-powered vehicle is designed as a bicycle and optionally has a drive machine designed as an electric motor. For example, the electrical energy required for the electric motor for driving can be generated at least partially by means of a generator driven by the driver.Further measures which improve the invention are described in more detail below together with the description of preferred exemplary embodiments of the invention on the basis of the figures. This shows FIG. 1 shows a schematic sectional illustration for illustrating an eccentric gearing according to the invention according to a first embodiment, FIG. 2 shows an enlarged detail of the eccentric gearing according to the invention according to the first embodiment, FIG. 3 shows a schematic perspective illustration of the eccentric gearing according to the invention according to the first embodiment, FIG. 4 shows a further schematic perspective illustration of the eccentric gearing according to the invention according to the first embodiment, FIG. 5 shows a schematic sectional illustration for illustrating an eccentric gearing according to the invention according to a second embodiment, FIG. 6 shows a schematic perspective illustration of the eccentric gearing according to the invention according to the second embodiment, and FIG. 7 shows a schematic illustration of a muscle-driven vehicle having an eccentric gearing according to the invention.FIG. 1 shows an eccentric gear 1 for a muscle-operated vehicle 2 which is illustrated in FIG. 8. The eccentric gear 1 comprises an eccentric wheel carrier 3 with a plurality of carrier pins 4, of which only one carrier pin 4 is shown in the present case, and two planetary rollers 5.1, 5.2 rotatably arranged on the respective carrier pin 4. The planetary rollers 5.1, 5.2 are rotatably mounted on the carrier bolt 4 via respective bearings and axially secured via a disk 14 fixed on the end face by means of screw means 13.Furthermore, the eccentric gear 1 comprises a housing 15, a ring gear toothing 9, an eccentric shaft 10 and two eccentric wheels 6.1, 6.2 each having a plurality of driver openings 7 distributed in the circumferential direction and a respective central eccentric receiving opening 8. The respective eccentric wheel 6.1, 6.2 runs in the ring gear toothing 9. The two eccentric wheels 6.1, 6.2 are mounted on the eccentric shaft 10 rotated by 180° with respect to one another with respect to the central axis 12 of the eccentric wheel carrier 3.A respective carrier bolt 4 is guided through a respective entrainment opening 7 on the first eccentric wheel 6.1 and on the second eccentric wheel 6.2. The respective first planetary roller 5.1 comes to rest in the respective driver opening 7 on the first eccentric wheel 6.1 and the respective second planetary roller 5.2 comes to rest in the respective driver opening 7 on the second eccentric wheel 6.2. In the present case, the respective planetary roller 5.1, 5.2 is designed to be spherical and the respective entrainment opening 7 in the respective eccentric wheel 6.1, 6.2 is designed to be conically tapered. A biasing spring 11 is arranged axially between the two planetary rollers 5.1, 5.2 on the respective carrier bolt 4 and loads the respective planetary roller 5.1, 5.2 in the direction of the conical narrowing in the respective driver opening 7. as a result, during operation of the eccentric gearing 1, a permanent contact between the respective planetary roller 5.1, 5.2 and the respective driver opening 7 in the respective eccentric wheel 6.1, 6.2 is ensured in order to improve the NVH behavior and to eliminate oscillations. In particular, during operation of the eccentric gear 1, a line contact is thereby permanently formed between the respective planetary roller 5.1, 5.2 and the respective driver opening 7 in the respective eccentric wheel 6.1, 6.2.FIG. 2 shows an enlarged detail from FIG. 1. In FIG. 2, the spherical, i.e. convexly shaped, outer circumferential surface of the respective planetary roller 5.1, 5.2 can be clearly seen on account of the enlarged illustration. Furthermore, FIG. 2 shows the entrainment opening 7, which is designed as a conical bore, in the respective eccentric wheel 6.1, 6.2. The respective prestressing spring 11 is designed in a compact manner as a corrugated spring, is arranged on the respective carrier bolt 4 between the two planetary rollers 5.1, 5.2, and presses the two planetary rollers 5.1, 5.2 outwards into the respective driver openings 7 in the first and second eccentric wheels 6.1, 6.2. The conicityes of the entrainment openings 7 in the first eccentric wheel 6.1 are embodied in the opposite direction to the conicityes of the entrainment openings 7 in the second eccentric wheel 6.2, wherein the respective diameter of the conical entrainment openings 7 in the respective eccentric wheel 6.1, 6.2 is reduced from the inside to the outside. The prestressing spring 11 is arranged on the inside between the two eccentric wheels 6.1, 6.2, i.e. in the region of the respectively largest diameter of the respective conical entrainment opening 7.FIG. 3 shows a section of the eccentric gear 1 with an electric machine arranged thereon, wherein in particular the two eccentric wheels 6.1, 6.2 and the eccentric wheel carrier 3 as well as the end faces of the eight carrier pins 4 arranged circumferentially on the eccentric wheel carrier 3 are readily visible. The planetary rollers 5.1, 5.2 arranged in the driver openings 7 are covered by the eccentric wheels 6.1, 6.2 and the eccentric wheel carrier 3. Furthermore, the housing 15 and the ring gear toothing 9 are not shown here.In FIG. 4, the perspective is changed compared to FIG. 3 and the two eccentric wheels 6.1, 6.2 are hidden in order to show the respective first and second planetary rollers 5.1, 5.2 and the respective prestressing spring 11 arranged axially between the two planetary rollers 5.1, 5.2 on the respective carrier bolt 4.FIGS. 5 and 6 show a second exemplary embodiment of the eccentric gearing 1, wherein in the present case exactly one planetary roller 5 is arranged on each carrier pin 4, and wherein exactly one preload spring 11 in each case presses the respective planetary roller 5 into a respective conical entrainment opening 7. It can be seen from FIGS. 5 and 6 that the biasing spring 11 is designed as a helical compression spring. The entrainment openings 7 in the respective eccentric wheel 6.1, 6.2 are formed so as to taper from the inside outwards, wherein the inside is where the eccentric wheels 6.1, 6.2 are arranged adjacent to one another. The conicityes of all the entrainment openings 7 in the first eccentric wheel 6.1 have the same orientation. The conicityes of all the entrainment openings 7 in the second eccentric wheel 6.2 have the same orientation. The planetary rollers 5 are rotatably mounted on the carrier bolt 4 via respective bearings and axially secured via a disk 14 fixed on the end face by means of screw means 13.FIG. 6 shows the eccentric gear 1 according to FIG. 5 in perspective. In the present case, the housing 15, the ring gear toothing 9 and the two eccentric wheels 6.1, 6.2 are omitted in order to show the respective planetary rollers 5 and the respective prestressing spring 11 arranged on the carrier bolt 4. The planetary rollers 5 are arranged alternately in the circumferential direction in a respective conical entrainment opening 7 on the first eccentric wheel 6.1 and in a respective conical entrainment opening 7 on the second eccentric wheel 6.2. The respective planetary roller 5 is pressed by the respective biasing spring 11 in the direction of the smaller diameter of the respective conical entrainment opening 7. The prestressing springs 11 were supported at least indirectly via further components, in particular sleeves or disks, alternately between a respective planetary roller 5 and the eccentric wheel carrier 3 and between the respective planetary roller 5 and the disk 14. Otherwise, the second exemplary embodiment according to FIGS. 5 and 6 corresponds to the first exemplary embodiment according to FIGS. 1 to 4, to which reference is made.FIG. 7 shows a muscle-powered vehicle 2 with an eccentric gearing 1 according to the invention, which is integrated in a drive arrangement 20. The muscle-powered vehicle 2 is designed as a bicycle which is substantially formed from a frame 21 and a front wheel 22 and a rear wheel 23. The drive arrangement 20 serves to drive the rear wheel 23. the rear wheel 23 thus forms a drive wheel of the bicycle, wherein the front wheel 22 remains driveless in the present case. The drive arrangement 20 comprises a generator module 24, a drive module 25 and an energy storage module 26. The generator module 26 is arranged in the region of the bottom bracket and can be driven by a user by bottoming force in order to generate electrical energy for the drive module 25. For this purpose, the generator module 24 has two cranks 27 arranged diametrically with respect to one another, which are set in rotation by pedaling force in order to generate electrical power in the generator module 24. In the present case, only one of the two pedal cranks 27 is shown.The bicycle does not have a mechanical drive connection between the cranks 27 and the drive wheel 23. The generator module 24 is electrically connected to the drive module 25 and the energy storage module 26 only via an electrical line 28 in order to provide the electrical energy required for the drive module 25. The drive module 25 can be designed, for example, as a wheel hub motor integrated into the rear wheel 23, which transmits an electric drive torque to the rear wheel 23. The drive module 25 can be supplied directly by the electrical energy generated by the generator module 24 or indirectly by the electrical energy stored in the energy storage module 26. The generator module 24 has an electric machine designed as a generator and the eccentric gearing 1, which are accommodated jointly in a housing arranged on the frame 21. For a detailed description of the mode of operation, reference is made to the prior art document mentioned at the beginning.List of reference characters1 Eccentric gear 2 muscle-driven vehicle 3 Eccentric wheel carrier 4 Carrier bolt 5 Planetary roller 5.1 First planetary roller 5.2 Second planetary roller 6.1 Eccentric wheel 6.2 Eccentric wheel 7 Entrainment opening 8 Eccentric receiving opening 9 Ring gear toothing 10 Eccentric shaft 11 Preload spring 12 Central axis 13 Screwing means 14 Disk 15 Housing 20 Drive arrangement 21 Frame 22 Front wheel 23 Rear wheel 24 Generator module 25 Drive module 26 Energy storage module 27 Pedal cranks 28 Line

Claims

Eccentric gear (1) for a muscle-driven vehicle (2), comprising an eccentric wheel carrier (3) with a plurality of carrier bolts (4) and at least one planetary roller (5, 5.1, 5.2) arranged rotatably on the respective carrier bolt (4), at least one eccentric wheel (6.1, 6.2) with a plurality of driver openings (7) and a central eccentric receiving opening (8), a ring gear toothing (9) and an eccentric shaft (10), wherein in each case one carrier bolt (4) is guided through in each case one driver opening (7) on the at least one eccentric wheel (6.1, 6.2) and the respective planetary roller (5, 5.1, 5.2) comes to bear in the respective driver opening (7), wherein the eccentric shaft (10) engages in the central eccentric receiving opening (8) and the at least one eccentric wheel (6.1, 6.2) runs in the ring gear toothing (9), wherein either the respective driver opening (7) or the respective planetary roller (5, 5.1, 5.2) is at least partially designed to be spherical, characterized in that the respective other of these two components is designed to be at least partially conically tapered, wherein at least one prestressing spring (11) is arranged on the respective planetary roller (5, 5.1, 5.2) and is designed to load the respective planetary roller (5, 5.1, 5.2) in the direction of the conical taper.Eccentric gear (1) according to Claim 1, characterized in that an outer circumferential surface of the respective planetary roller (5, 5.1, 5.2) is at least partially designed in a spherical manner, the respective entrainment opening (7) being designed as a conical bore in the respective eccentric wheel (6.1, 6.2).Eccentric gear (1) according to one of the preceding claims, characterized in that exactly one first and one second planetary roller (5.1, 5.2) are arranged on each carrier pin (4), wherein the prestressing spring (11) is arranged axially between the two planetary rollers (5.1, 5.2) on the respective carrier pin (4).Eccentric gear (1) according to Claim 1 or 2, characterized in that exactly one planetary roller (5) is arranged on each carrier bolt (4), exactly one prestressing spring (11) pressing the planetary roller (5) into the conical entrainment opening (7).Eccentric gear (1) according to Claim 4, characterized in that the planetary rollers (5) are arranged alternately in the circumferential direction in a respective conical entrainment opening (7) on a first eccentric wheel (6.1) and in a respective conical entrainment opening (7) on a second eccentric wheel (6.2).Eccentric gear (1) according to Claim 5, characterized in that the conicityes of all the driver openings (7) in the first eccentric wheel (6.1) have the same orientation, wherein the conicityes of all the driver openings (7) in the second eccentric wheel (6.2) have the same orientation.Eccentric gear (1) according to Claim 5 or 6, characterized in that the conicityes of the entrainment openings (7) in the first eccentric wheel (6.1) are designed opposite to the conicityes of the entrainment openings (7) in the second eccentric wheel (6.2).Eccentric gear (1) according to one of the preceding claims, characterized in that the respective prestressing spring (11) is designed either as a helical compression spring or as a corrugated spring.Muscle-operated vehicle (2) having an eccentric gearing (1) according to one of the preceding claims.

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