DE102022116701A1 - Drive assembly with eccentric gear for a human-powered vehicle and vehicle with the drive assembly - Google Patents

Abstract

The invention relates to a drive arrangement for a human-powered vehicle, which is compact and is characterized by improved efficiency.

Description

The invention relates to a drive assembly for a human-powered vehicle having the features of the preamble of claim 1. The invention also relates to a vehicle having the drive assembly.

Electric bicycles are known which can be driven without a physical drive connection between the crank and the rear wheel. The driver uses the pedal cranks to drive a generator to generate electricity in order to supply electricity to a drive motor connected to the rear wheel. With such a drive system, the physical drive connection, such as a chain, toothed belt, cardan shaft, etc., can be omitted. In order to increase the speed of the crankshaft and reduce the torque accordingly, conventional gear types, such as single or multi-stage planetary gears, tungsten sets, etc., are usually used in order to be able to use a generator with little torque and a correspondingly small size.

The pamphlet DE 196 00 698 A1 discloses a vehicle that can be operated with muscle power, in particular a bicycle. The bicycle has a generator drivable by a vehicle user to generate electricity, and at least one electric motor for driving the vehicle, which is connected to the generator for transmitting electric power. In particular, between a pedal crank for driving the generator and the generator, a step-up gear is provided for a higher speed, the gear being a planetary gear, which is preferably at least partially accommodated inside the generator.

The U.S. 2014/0 083 245 A1 describes a harmonic reduction gear with clutch function comprising a circular spline shaft, a mounting base, a flexspline and a shaft generator. When a power source drives the shaft generator to rotate in a first direction, a one-way clutch engages to lock the submount, deforming the flexspline and thus rotating the circular keyway in the first direction. When an external force is applied to the output shaft in the first direction, the mounting base is driven through the flexspline so that the one-way clutch disposed thereon is disengaged by a force in a second direction. At this moment, the rotational speed of the wave generator is zero relative to the flexspline, so the wave generator can be driven by the circular spline to rotate along with the flexspline, and the central axis of the wave generator can be driven to rotate as well .

The US 2012/ 0 165 150 A1 and the U.S. 8,646,560 B2 describe a motor unit wherein a controller disposed in the motor housing at one end thereof controls the power supply to the motor in response to a sensed amount of torque to vary the amount of motor motive power provided to the motor shaft. An actuator that couples a torque sensor to a sensor of the controller is disposed in a hollow bore of the motor shaft and is configured to move relative to the controller sensor, causing the sensor to generate a signal indicative of the sensed torque level.

The WO 2016/ 164 486 A1 describes a lightweight, compact electric drive unit with a high reduction ratio. One or more cycloidal gears within a housing have cycloidal gears. Which mesh with gears on the inside of the case.

The DE 10 2010 017 829 A1 describes a motor-gear unit for a bicycle that is attached or flanged directly to a standard bottom bracket shell. The standard bottom bracket housing is arranged between the motor-gear unit and a chainring.

The invention is based on the object of proposing a drive arrangement for a human-powered vehicle which is compact and is characterized by improved efficiency.

This object is achieved by a drive assembly having the features of claim 1 and a vehicle having the features of claim 6. Preferred or advantageous embodiments of the invention result from the dependent claims, the following description and/or the attached figures.

The subject matter of the invention is a drive arrangement which is designed and/or suitable for a human-powered vehicle. In particular, the vehicle is designed as an electric bicycle, also known as an e-bike. In principle, the bicycle can have exactly two wheels. Alternatively, however, the vehicle can also have more than two, in particular three or exactly four wheels.

The drive module preferably includes at least one electric motor, which converts electrical energy into an electrical drive torque. In this case, the electric motor can be and/or is connected in terms of drive technology to at least one drive wheel of the vehicle. The connection can be made via traction means, for example via a chain ring and a chain.

Basically, the drive wheel is designed as a rear wheel of the vehicle. Alternatively, however, the drive wheel can also be designed as a front wheel of the vehicle.

The drive arrangement has a drive module, which is designed to convert electrical energy into mechanical energy and includes an electrical machine and a transmission device.

The vehicle user can preferably vary the size of the electrical power depending on the pedaling force or pedaling frequency. The drive arrangement preferably has a control device which is designed to control the drive torque and/or a drive speed of the drive module as a function of the pedaling force and/or pedaling frequency.

The drive module has a pedal crankshaft. This is designed to be acted upon by the drive power of the electrical machine. For this purpose, a pedal crank is preferably arranged on the end of the pedal crankshaft and is rotatably mounted in the drive module. The pedal crankshaft preferably defines a main axis of rotation of the drive module with its axis of rotation. The crankshaft runs continuously from one crank to the other crank.

The drive module has a transmission device which is designed and/or suitable for converting the torque provided by the electric machine into a pedal force support on the pedal crankshaft. The pedal crankshaft is connected in terms of transmission to the electric machine via the transmission device. In particular, the transmission device is used for stepping down (amount (i)>1), with the speed at the pedal crankshaft being reduced and the torque transmitted thereto being increased.

In the context of the invention, it is proposed that the gear device be designed as an eccentric gear. In particular, the eccentric gear has a gear input, in particular an input element, and a gear output, in particular an output element, with the pedal crankshaft being arranged on the input side and the electric machine on the output side. In particular, a power transmission path for transmitting the torque runs from the electric machine via the eccentric gear to the pedal crankshaft. For this purpose, the pedal crankshaft is guided through the eccentric gear in the axial direction with respect to the main axis of rotation and/or is arranged coaxially with the eccentric gear.

The advantage of the invention is, in particular, that by using an eccentric gear, a particularly low-noise gear with a compact design is proposed. A drive module can thus be implemented which is characterized by a small installation space. In contrast to application-specific planetary gear stages, there are no corresponding development efforts, such as time, costs, risk, etc. Furthermore, eccentric gears allow a continuous shaft in the center, which is a basic requirement for use in bicycles with pedal cranks arranged on both sides.

According to the invention, the eccentric gear has a roller carrier with driver rollers as a first element. The roller carrier is particularly preferably designed as a roller disk. The driver rollers are regularly distributed in the direction of rotation on a common pitch circle around the main axis. The entrainment rollers extend in an axial direction and/or parallel to the main axis. Furthermore, according to the invention, the eccentric gear has at least two cam discs. The cam discs each have driver openings for the driver rollers and a central eccentric receiving opening. The free diameter of the driver openings is larger than the diameter of the driver rollers. In particular, the cam disc is designed as a flat disc. The cam disc has a curved shape on the outer circumference. According to the invention, the eccentric gear also has a ring gear section as a second element. The ring gear section can be designed in one piece or in multiple pieces. During operation, the at least two cam discs run with their outer circumference on the ring gear section. The eccentric gear has an eccentric shaft as an input element. The eccentric shaft has at least one eccentric section, the eccentric section having a circular cross section. The eccentric section engages in the central eccentric receiving opening. A disk bearing device is preferably arranged between the eccentric section and the eccentric receiving opening in order to reduce the friction.

The curved shape of the cam discs and the inner contour of the ring gear section can in principle be of any desired design, as long as they can take over the function of the eccentric gear. However, the eccentric gear is particularly preferably designed as a cycloidal gear, where a cycloid shape is represented by the outer circumference of the at least two cam discs.

In a further specification, it is provided that the drive module has a stator and a rotor, with the eccentric shaft being connected to the rotor in a rotationally fixed manner. When driving, the torque of the rotor is thus applied to the pedal crankshaft via the eccentric gear, so that the rotor is rotated relative to the stator about the main axis of rotation. In particular, the eccentric shaft is positively and/or non-positively and/or cohesively connected to the rotor, preferably at least in a rotationally fixed manner. Alternatively, the eccentric shaft and the rotor can also be formed from a common material section. The eccentric shaft is preferably arranged coaxially and/or concentrically to the rotor in relation to the main axis of rotation. A drive module is therefore proposed which is characterized by a particularly compact design.

In a further specific implementation, it is provided that the eccentric shaft has a hollow shaft section for the passage of the pedal crankshaft, with the pedal crankshaft being rotatably mounted on an inner circumference of the hollow shaft section. In particular, the inner circumference of the hollow shaft section has at least one bearing seat for a bearing device, preferably a roller bearing, via which the pedal crankshaft is rotatably supported on the hollow shaft section. The rotor is preferably mounted in a rotationally fixed manner on an outer circumference of the hollow shaft section.

In a preferred implementation, it is provided that the eccentric gear has a transmission ratio between gear input and gear output of less than 30:1. The eccentric gear preferably has a transmission ratio of between 30:1 and 100:1. The eccentric gear preferably has a transmission ratio of 50:1. In this way, the low torque generated by the electric machine at the transmission input at high speeds is converted into a higher torque at low speeds at the transmission output.

In principle, the driver rollers can be arranged rigidly on the roller carrier. However, it is provided according to the invention that the driver rollers each have a bolt, a roller bearing and a roller sleeve for transmitting the torque to the cam disk or disks. The roller sleeve is preferably designed as a non-cutting part and/or formed part. According to the invention, the bolts are fixed on the roller carrier. According to the invention, a roller bearing is arranged between the bolts and the roller sleeves. In principle, it can be a plain bearing, but the roller bearing is preferably designed as a rolling body bearing. With this configuration, low-noise operation with low friction losses can be achieved in the generator module.

In a preferred implementation of the invention, the eccentric gear has two cam discs offset diametrically and/or oppositely in the disc plane, e.g. by 180° in the direction of rotation. The cam disks are preferably arranged axially adjacent to one another. The cam discs are preferably arranged in contact with one another and/or slide off one another during operation. This implementation reduces transverse forces in the eccentric gear.

In a further specific implementation, it is provided that the drive module has a housing which is designed and/or suitable for accommodating the electrical machine and the eccentric gear. In particular, the electric machine and the eccentric gear are completely accommodated in the housing. The pedal crankshaft is preferably guided in sections through the housing, with the pedal crankshaft being supported radially on the housing via at least one further bearing device, preferably a roller bearing. The housing can be constructed in several parts, preferably in two parts. In particular, the housing has an accommodation space for accommodating the eccentric gear and the electric machine, the eccentric gear and the electric machine being accommodated in the housing in a form-fitting manner in the axial and/or radial direction in relation to the main axis of rotation. The stator is preferably firmly connected to the housing.

In a further specification, it is provided that the eccentric gear, the pedal crankshaft and the electrical machine are arranged coaxially and/or concentrically with respect to the main axis of rotation. An eccentric gear is thus proposed which is characterized by a small axial overall width and at the same time a rotationally symmetrical structure.

In a preferred implementation, the roller carrier forms the output element of the gear device, in particular the eccentric gear. In particular, the roller carrier is non-rotatably connected to the pedal crankshaft. In this configuration, the drive module can be implemented in a particularly compact manner. In this embodiment, the ring gear section is arranged in a rotationally fixed manner. For example, the ring gear section is rotatably fixed in the housing or is formed by the housing.

In a development of the invention, the ring gear section includes a plurality of bolt sections, which are axially aligned and distributed regularly in the direction of rotation. Provision is made for the at least one cam disk to run on the bolt sections. The bolt sections are particularly preferably designed as cylindrical pins, specifically as hardened cylindrical pins, which can be inserted, for example, into bores in one or the housing of the drive module or alternatively into a rotatable carrier as a ring gear section. In this way, the function of the ring gear section can be implemented in a way that optimizes costs and space.

According to the invention, the ring gear section forms the output element in the transmission device. In particular, the roller carrier is arranged rigidly. However, this configuration leads to a somewhat larger design.

According to the invention, the pedal crankshaft has a shaft section and a shaft extension for connection to the pedal crank. The shaft section preferably runs through the electric machine. According to the invention, it is further provided that the shaft section and the shaft extension are detachably connected to one another. In particular, the shaft extension and the shaft section can be plugged into one another. This proposes an intermediate piece between the shaft section and the pedal crank in the form of the shaft extension. In this way, both the interface to the shaft section and the interface to the pedal crank can be designed independently of one another and thus in each case in a functional manner. Furthermore, there is scope for designing the shaft extension so that it can also be functionally adjusted between the interfaces. According to the invention, the output member is designed in one piece with the shaft extension. Thus, the transmission input is designed in one piece with the relevant shaft extension. As a result, an otherwise required, torque-transmitting connection between the shaft extension and the component representing the transmission input is saved. Furthermore, another function is assigned to the shaft extension. For example, the shaft extension is formed in one piece with the roller carrier or with the ring gear section.

In a preferred development, a maximum outside diameter of the shaft extension is greater than a maximum outside diameter of the shaft section in a region of the electrical machine. As an alternative or in addition, the maximum outside diameter of the shaft extension is designed to be larger than a minimum free diameter through the electrical machine. This development is based on the consideration that the outer diameter of the pedal crankshaft is limited by the electrical machine. On the other hand, it is advantageous if the pedal crank acts on the pedal crank shaft over a larger diameter. The at least or exactly two-part design allows the shaft section to be inserted into the generator and pushed through and then connected to the shaft extension, the shaft extension having a larger outer diameter than the shaft section for coupling the pedal crank.

In a preferred implementation of the invention, the shaft section and the shaft extension are positively connected to one another in the direction of rotation. For example, a spline can be used, in particular with teeth running in the axial direction. Alternatively, a polygon connection can be used, in particular with a P3G profile (triangle) or a P4C profile (square). This shaft-hub connection ensures reliable torque transmission. The shaft section and the shaft extension are preferably screwed together in a coaxial direction. A first coaxial axle screw can particularly preferably be used here, which is screwed into the shaft section.

In a preferred development of the invention, the shaft extension has an internal thread for receiving a second coaxial axle bolt for fastening the pedal crank. In particular, the first coaxial axle bolt and the second coaxial axle bolt are arranged one behind the other in the axial direction. This forms a particularly stable pedal crankshaft.

Optionally, the drive arrangement includes the pedal crank or pedal cranks, the pedal crank being slipped onto the shaft extension and being positively connected to the shaft extension in the direction of rotation. Furthermore, the drive arrangement includes the second coaxial axle screw for fastening the pedal crank, which is screwed into the internal thread. A crank bolt, for example an ISIS crank bolt, is preferably used as the second coaxial axle bolt. The shaft extension ensures that sufficient radial space is available for the second coaxial axle bolt.

On the opposite side, the pedal crankshaft has another pedal crank. A further shaft extension is preferably provided here, with the shaft section being formed in one piece with the further shaft extension in one possible embodiment. In this configuration, the shaft section with the one-piece shaft extension from an axial side by the electrical Machine sections are pushed through and then connected to the separate shaft extension. The integrally connected shaft extension is preferably arranged on the side facing away from the transmission, so that the shaft extension and the input element can be designed in one piece on the transmission side. This makes it possible for both shaft extensions to have a larger outside diameter than the shaft section.

In another possible configuration, the further shaft extension is detachably connected to the shaft section. In particular, the further shaft extension is structurally identical or mirror-symmetrical to the shaft extension described above.

Optionally, in addition, the drive module is connected indirectly via an energy storage module to provide the electrical energy.

A further object of the invention relates to a vehicle with the drive arrangement as already described above. In particular, the vehicle is designed as a human-powered vehicle, in particular a bicycle, which is driven by an electric motor. In particular, the vehicle is characterized in that the electrical energy required for the electric motor is provided at least partially by means of the drive module.

• 1 eine schematische Darstellung eines Fahrzeugs mit einer Antriebsanordnung als ein Ausführungsbeispiel der Erfindung;
• 2 eine Schnittdarstellung eines Antriebsmoduls der Antriebsanordnung;
• 3 eine dreidimensionale Darstellung der Getriebeeinrichtung in der 2;
• 4 eine axiale Draufsicht auf die Getriebeeinrichtung in der 2 und 3;
• 5 eine Schnittdarstellung einer alternativen Getriebeeinrichtung der Antriebsanordnung in der 1.

Further features, advantages and effects of the invention result from the following description of a preferred exemplary embodiment of the invention and the attached figures. show:

• 1 a schematic representation of a vehicle with a drive arrangement as an embodiment of the invention;
• 2 a sectional view of a drive module of the drive assembly;
• 3 a three-dimensional representation of the transmission device in the 2 ;
• 4 an axial plan view of the transmission device in FIG 2 and 3 ;
• 5 a sectional view of an alternative transmission device of the drive arrangement in FIG 1 .

Corresponding or identical parts are each provided with the same reference symbols in the figures.

1 shows a muscle-powered vehicle 1 in a highly simplified representation. The vehicle 1 is designed as a bicycle, which is essentially formed from a frame 2 and a front wheel 3 and a rear wheel 4 .

The vehicle 1 has a drive arrangement 5 which is used to drive the rear wheel 4 . The rear wheel 4 thus forms a drive wheel of the vehicle 1, with the front wheel 3 remaining unpowered. Optionally, however, it can also be provided that the front wheel 3 is driven.

The drive arrangement 5 comprises a drive module 6 and an energy storage module 8. The drive module 6 is arranged in the area of the bottom bracket. For this purpose, the drive module 6 has two pedal cranks 9 arranged diametrically opposite one another.

The bicycle has a mechanical drive connection between the pedal cranks 9 and the drive wheel 4 via traction means, not shown here. The energy storage module 8 can be charged from an external power source.

The 2 shows the drive module 6 in a longitudinal section along a main axis of rotation H. The drive module 6 has a pedal crankshaft 14 which defines the main axis of rotation H with its axis of rotation. In an installation situation, the pedal cranks 9 are mounted on the end of the pedal crankshaft 14 .

The drive module 6 has an electric machine 15 and a transmission device 16 which are accommodated together in a housing 17 . The electric machine 15 has a stator 18 and a rotor 19 , the pedal crankshaft 14 being connected to a transmission input and the rotor 19 being connected to a transmission output of the transmission device 16 . The stator 18, on the other hand, is fixed to the housing 17 and thus remains stationary.

The gear device 16 is designed as an eccentric gear 20 . With respect to the main axis of rotation H, the eccentric gear 20 is arranged coaxially with the electric machine 15 and the pedal crankshaft 14 and in the axial direction with a positive fit between the electric machine 15 and the housing 17 . The housing 17 is designed in two parts, with the housing 17 having a housing base body 21 which is closed off in the axial direction by a housing cover 22 . The housing base body 21 and the housing cover 22 each have a central through-opening 23 , 24 which serves to guide the pedal crankshaft 14 through the housing 17 .

The eccentric gear 20 has a roller carrier 25 as an output element, which is arranged in a rotationally fixed manner with the pedal crankshaft 14 . Furthermore, two cam discs 26, 27 are provided, the cam discs 26, 27 having an eccentric mount opening 48 ( 3 ) and a plurality of off-center cam apertures 49 ( 3 ) exhibit. The cam disks 26, 27 are offset by 180° and arranged opposite one another in order to reduce lateral forces during operation. The roller carrier 25 has a plurality of driver rollers 28, the driver rollers 28 engaging in the driver openings 49 of the cam discs 26, 27, so that these are driven in the direction of rotation by the driver rollers 28 and thus by the roller carrier 25.

The eccentric gear 20 has a ring gear section 29, the ring gear section 29 having a plurality of bolt sections 50 running in the axial direction. The bolt sections 50 are in the form of hardened cylinder pins which are pushed into bores in the housing 17 . The outer circumference of the cam discs 26, 27 is formed in a wave shape, which engages in the ring gear section 29 only in sections, namely offset by 180°. In particular, the waveform is formed as a cycloid shape.

An input element of the eccentric gear 20 is designed as a hollow shaft 30, the hollow shaft 30 having two eccentric sections 31, 32, the eccentric sections 31, 32 engaging in the eccentric receiving opening of the cam discs 26, 27 via a disc bearing device 33, 34 in each case. The hollow shaft 30 is connected to the rotor 19 in a torque-proof manner. When the hollow shaft 30 rotates, the pedal crankshaft 14 is also rotated and the rotational movement is reduced to a slower speed. In a preferred implementation, it is provided that the eccentric gear 20 has a transmission ratio between the gear input and the gear output with an amount of less than 30:1. The eccentric gear 20 preferably has a transmission ratio of between 30:1 and 100:1. The eccentric gear 20 preferably has a transmission ratio of 50:1.

In this exemplary embodiment, the pedal crankshaft 14 has three subcomponents, namely a central shaft section 35 and shaft extensions 36, 37, which are placed on the central shaft section 35 at the ends. The shaft section 35 is arranged coaxially with the rotor 19 and in the same axial section as the rotor 19 . In particular, the shaft section 35 protrudes beyond the rotor 19 on both sides in the axial direction. A maximum outer diameter of the shaft section 35 is dimensioned smaller than the free inner diameter of the rotor 19 and/or the hollow shaft 30. The shaft extensions 36, 37 are placed on the shaft section 35 at the ends. For this purpose, the shaft extensions 36, 37 have receptacles 38, 39 into which the respective end of the shaft section 35 is inserted. The receptacles 38, 39 each form, together with the ends of the shaft section 35, a positive shaft-hub connection in the direction of rotation. For example, it can be a polygonal connection or a spline. For the axial attachment and/or securing of the shaft extensions 36, 37, first axle screws 40, 41 are screwed into the shaft section 35, which fix the shaft extensions 36, 37 in the axial direction with the screw heads. The shaft extensions 36 , 37 each have a first interface with the shaft section 35 .

The pedal cranks 9 are placed on the axial outside of the shaft extensions 36, 37 and fastened via a second axle screw 42, 43, which is screwed into an internal thread 12, 13 of the shaft extension 36, 37 and with the screw head in each case the pedal crank 9 in the axial direction fixed. The shaft extensions 36, 37 each have a second interface to the respective pedal crank 9. The first and second axle bolts 40, 42 and 41, 43 are arranged axially one behind the other.

The detachable connection between the shaft extensions 36, 37 and the shaft section 35 means that the shaft extensions 36, 37 can have a larger maximum outer diameter than the shaft section 35 and are nevertheless designed to be suitable for assembly. A further advantage is that the first and the second interface can be designed according to the load without having to take into account the restriction of a maximum outer diameter which has to be pushed through the rotor 19 during assembly. The first and the second interface are arranged axially offset from one another, so that they do not mutually influence one another in the design.

• So weist das Antriebsmodul 6 Lagereinrichtungen 44, 45 auf, wobei die Lagereinrichtungen 44, 45 als Wälzlagereinrichtungen, insbesondere als Kugellagereinrichtung ausgebildet sind. Die Lagereinrichtungen 44, 45 lagern die Tretkurbelwelle 14 relativ zu dem Gehäuse 17 relativ zu einem Gehäuseabschnitt des Gehäuses 17. Dabei sind die Wellenfortsätze 36, 37 jeweils als Lagerpartner der Lagereinrichtungen 44, 45 ausgebildet und tragen jeweils einen Innenring der Lagereinrichtungen 44, 45 an deren Außenumfang. Der jeweilige Außenring ist in dem Gehäuse 17 angeordnet. Dadurch, dass der Außendurchmesser der Wellenfortsätze 36, 37 größer als der Außendurchmesser des Wellenabschnitts 35 ausgebildet ist, können im Durchmesser größere Lagereinrichtungen 44, 45 verwendet werden, so dass gemeinsam mit dem stabilen Verbund aus Wellenabschnitt 35 und Wellenfortsatz 36, 37 eine höhere Steifigkeit der Lagereinrichtungen 44, 45 erreicht werden können.

A further advantage results from the fact that further functions can be implemented on the outer circumference of the shaft extensions 36, 37:

• The drive module 6 has bearing devices 44, 45, with the bearing devices 44, 45 being designed as roller bearing devices, in particular as ball bearing devices. The bearing devices 44, 45 mount the pedal crankshaft 14 relative to the housing 17 relative to a housing section of the housing 17. The shaft extensions 36, 37 are each designed as bearing partners of the bearing devices 44, 45 and each carry an inner ring of the bearing devices 44, 45 on their outer perimeter. The respective outer ring is arranged in the housing 17 . Because the outer diameter of the shaft extensions 36, 37 is larger than the outer diameter of the shaft section 35 is formed, bearing devices 44, 45 with a larger diameter can be used, so that together with the stable combination of shaft section 35 and shaft extension 36, 37, greater rigidity of the bearing devices 44, 45 can be achieved.

In addition, the generator module 6 has sealing devices 46, 47 which seal the pedal crankshaft 14 in relation to the housing 17 at the respective passage openings 23, 24. The sealing devices in 46, 47 run on the shaft extensions 36, 37. The shaft extensions 36, 37 thus form sealing partners in the sealing devices 46, 47. Thus, no seals have to be introduced inside the housing 17.

In the case of the drive module 6 it is also provided that the roller carrier 25 of the eccentric gear 20 is designed in one piece as a gear input/input element with the shaft extension 36 . The shaft extension 36 thus assumes an additional function. This results in the particular advantage that a shaft-hub connection between the pedal crankshaft 14 and the transmission device 16 can be saved.

A conventional pedal crankshaft, as is known from conventional bicycles, cannot be designed with a larger diameter on both sides (e.g. for stable accommodation of pedal cranks with e.g. ISIS teeth), since components arranged so centrally can no longer be attached. If these components were therefore designed to be larger in diameter, the overall outer diameter of the module would also (unnecessarily) increase, which increases installation space, costs and mass.

If, for example, a corresponding DIN toothing is chosen to hold the pedal cranks, which makes do with a smaller diameter so that all components can be attached from the shaft ends, then specially manufactured pedal cranks must be used, which affects the choice of crank lengths, designs, crank -Offset (Q-factor/"stand width") is severely limited or expensive because of the small number of items.

If, instead of the special pedal cranks, only crank adapters are attached to the continuous pedal crankshaft in order to be able to use standard cranks (e.g. ISIS), these can only be designed with a small wall thickness, which leads to losses in stability and causes higher costs due to the additional shaft connection required.

In order to be able to produce a stable pedal crankshaft 14 which has a small diameter in its (axial) center but a larger diameter at each end, it is therefore proposed to design the pedal crankshaft 14 in several parts (e.g. two-part or three-part).

The assembly consists (in the case of a three-piece design as in Fig 2 ) from the shaft section 35 as a central shaft with a small diameter, which has a shaft connection at each of its ends. This can be in the form of a spline or in the form of a P3G polygon connection. A shaft extension 36, 37 is placed on each of these shaft connections and is preferably bolted axially to the shaft section 35 by means of the first axle screw 40, 41. The pedal crankshaft 14 is supported via the shaft extensions 36, 37 and not via the shaft section 35, in order to represent a stable combination and—in favor of rigidity—to be able to use larger bearing devices 44, 45. The sealing devices 46, 47 as housing or cover seals are also provided continuously on the shaft extensions 36, 37, so that no seal inside the housing 17 is required.

Due to the shaft ends leading out of the drive module 6 in one piece (not radially nested as in the case of plugged-on adapters) and designed as the shaft extensions 36, 37 of the pedal crankshaft 14, it is also possible to use standardized ISIS crank bolts as second axle bolts 42, 43, which is the case with plugged-on adapters would not be possible, since too small radial component wall thicknesses would remain. The transmission input/input element driven by the drive shaft can also be made in one piece with the relevant shaft extension 36, 37. As a result, an otherwise required torque-transmitting connection (e.g. spline) between the shaft extension 36 and the component representing the transmission input/input element is saved (costs, installation space, mass).

Since additional components (gear parts/bearings, etc.) can/must be attached to the pedal crankshaft 14 during assembly from only one side, the pedal crankshaft 14 can alternatively only be made in two parts. In this case, the shaft section 35 and one of the two shaft extensions 36, 37 are made together in one piece. This is preferably done on the side of the generator module 6 on which the transmission device 16 is not located, so that on the transmission side the shaft extension 36 and the transmission input/input element can be made in one piece. The pedal crankshaft 14 is mounted relative to the hollow shaft 30 and/or to the rotor 19 via a rotor bearing device 51 which is arranged in the end region of the rotor 19 and as a rolling element layer tion is formed. Furthermore, the pedal crankshaft 14 is mounted against the hollow shaft 30 and/or the eccentric sections 31, 32 via a roller bearing device in the region of the gear device 16.

The 3 shows a schematic, three-dimensional representation of the gear device 16 or the eccentric gear 20, designed as a cycloidal gear. In conjunction with the representations of 2 and 4 , which shows an axial plan view of the same assembly, it can be seen that the driver rollers 28 each have a bolt 52, the bolt 52 being fixed in a roller disk 53 of the roller carrier 25, for example being pressed. A roller sleeve 54 is in each case placed coaxially on the bolt 52 , the roller sleeve 54 being mounted on the bolt 52 via a roller bearing 55 . The roller bearing 55 is designed as a sliding bearing or as a rolling element bearing. The outer diameter of the driver rollers 28 and/or the roller sleeves 54 is larger than the driver openings 49 so that the roller sleeves 54 can run off the inner circumference of the driver openings 49 . The roller disk 53 is formed in one piece with the shaft extension 36, so that a shaft-hub connection is saved here.

In order to further reduce the friction losses in the drive module 6, in particular in the gear mechanism 16 and in particular in the eccentric gear 20, the gear chamber is provided with oil or grease lubrication, with the gear chamber being separated by an intermediate wall 56 and a seal 57 relative to the hollow shaft 30 of a drying room for the generator and the electronics.

The 5 shows a second embodiment of the drive module 6 in the drive assembly 5 of FIG 1 . In the 5 a longitudinal section along the main axis of rotation H is shown, with only the differences to the drive module 6 in FIG 2 is received. In contrast to the drive module 6 in the 2 here the ring gear section 29 forms the input member and/or the gear input into the gear device 16 or the eccentric gear 20. The ring gear section 29 can be used in a manner similar to that in FIG 2 be realized by a plurality of bolt sections 50 arranged in the direction of rotation, embodied in particular as hardened cylindrical pins. In the exemplary embodiment shown, the ring gear section 29 has a carrier 58, the carrier 58 being arranged on the pedal crankshaft 14 in a rotationally fixed manner. However, it is also possible that the carrier 58 with a shaft extension, such as the shaft extension 36 in the 2 is formed in one piece. Furthermore, the pedal crankshaft 14 can also be designed in two or more parts, as in FIG 2 .

Reference List

1

vehicle

2

Frame

3

front wheel

4

rear wheel

5

drive assembly

6

drive module

8th

energy storage module

9

crank

10

Management

11

consumer

12

inner thread

13

inner thread

14

pedal crankshaft

15

electric machine

16

gear mechanism

17

Housing

18

stator

19

rotor

20

eccentric gear

21

housing body

22

housing cover

23

Through hole in the housing cover

24

Through hole in the housing body

25

role carrier

26, 27

cam discs

28

carrier rollers

29

ring gear section

30

hollow shaft

31, 32

eccentric sections

33, 34

disc storage facility

35

wave section

36, 37

corrugated processes

38, 39

Recordings

40, 41

first axle bolt

42, 43

second axle bolt

44, 45

storage facilities

46.47

sealing devices

48

eccentric receiving opening

49

flight openings

50

bolt sections

51

rotor bearing device

52

bolt

53

roller disc

54

reel sleeve

55

roller storage

56

partition

57

poetry

58

carrier

H

main axis of rotation

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 19600698 A1 [0003]
• US 2014/0083245 A1 [0004]
• US 2012/0165150 A1 [0005]
• US8646560B2 [0005]
• WO 2016/164486 A1 [0006]
• DE 102010017829 A1 [0007]

Claims (6)

Drive arrangement (5) for a human-powered vehicle (1) with a drive module (6) for converting electrical energy into mechanical energy, the drive module (6) has an electric machine (15) which applies torque to the pedaling force of a user of a vehicle equipped with the drive arrangement, has a pedal crankshaft (14) which is connected to the electric machine (15) via a gear device (16), the gear device (16) being designed to convert the torque of the electric machine (15) to the pedal crankshaft (14), wherein the electric machine (15) can be and/or is drivingly connected to at least one drive wheel of the vehicle, whereby the gear device (16) is designed as an eccentric gear (20) which has a roller carrier (25) with driver rollers (28) as a first element, at least two cam discs (26, 27) with driver openings (49) and a central eccentric receiving opening (48), the driver rollers (28) engaging in the driver openings (49), a ring gear section (29) as a second organ, the cam discs (26, 27) running on the ring gear section (29) with their outer circumference, and has an eccentric shaft as the output element, the eccentric shaft having at least one eccentric section (31,32), the eccentric section (31,32) engaging in the central eccentric receiving opening (48), the driver rollers (28) each having a bolt (52), a roller bearing (55) and a have roller sleeves (54), the roller sleeves (54) being rotatably arranged on the bolts (52) via the roller bearing (55) and the bolts (52) being fixed in the roller carrier (25), the ring gear section (29) forming the output element in the transmission device (16), wherein the pedal crankshaft (14) has a shaft section (35) and a shaft extension (36,37) for connection to the pedal crank (9), the shaft section (35) and the shaft extension (36,37) being detachably connected to one another and the Shaft extension (36,37) is formed in one piece with the output member. Drive arrangement (5) after claim 1 , characterized in that the eccentric gear (16) has two cam discs (26, 27) offset diametrically and/or in opposite directions. Drive arrangement (5) according to one of the preceding claims, characterized in that the ring gear section (29) is formed by a plurality of bolt sections (50), the at least two cam disks (26, 27) running on the bolt sections (50). Drive arrangement (5) according to one of the preceding claims, characterized in that the drive-related connection between the electric machine (15) and the at least one drive wheel of the vehicle can be implemented or is implemented via a chain ring and traction means. Drive arrangement (5) after claim 4 , characterized in that there is a rigid connection between the pedal crankshaft and the chainring as the output element of the drive module. Vehicle (1) with the drive arrangement (5) according to one of the preceding claims.

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