METHOD FOR CONTROLLING A DRIVE DEVICE OF A BICYCLE, DRIVE DEVICE FOR A BICYCLE AND BICYCLE
Patent Information
- Application Number
- DE502021007354
- Authority / Receiving Office
- DE · DE
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2020-07-24
- Filing Date
- 2021-07-13
- Publication Date
- 2025-05-22
- Estimated Expiration
- 2041-07-13
AI Technical Summary
Existing electric bicycle drive systems exhibit indirect driving behavior, leading to low pedal resistance and delayed reaction to changes in pedaling force or speed, resulting in rotor slipping and an unsatisfactory riding experience.
A control procedure for a bicycle drive device that records the speed of the crank axis and adjusts the motor speed of an electric motor to optimize the translation ratio of a planetary gear, ensuring quick adaptation to changes in speed or pedaling force within milliseconds.
This solution provides a direct driving experience with increased pedal resistance and rapid response to pedaling changes, reducing rotor slipping and enhancing the overall riding experience while also reducing maintenance efforts.
Description
[0001] The present invention relates to a method for controlling a drive device of a bicycle, wherein the method comprises detecting a rotational speed of the pedal axle and generating a control motor speed as a function of the detected rotational speed for adjusting a gear ratio of a planetary gear. The invention further comprises a drive device for a bicycle, wherein the drive device has a planetary gear and a control electric motor for generating the control motor speed. The invention further relates to a bicycle with the drive device. State of the art
[0002] DE 10 2016 207 035 A1 discloses an electric bicycle with a planetary gear system located in the bottom bracket in addition to the electric motor. The gear system has a limited number of selectable gear ratios and requires a relatively large installation space.
[0003] Document DE 10 2013 012 160 A1 discloses a continuously variable transmission for a bicycle featuring double-tapered rollers. This transmission exhibits reduced efficiency and requires a relatively large installation space.
[0004] WO 2010 / 092331 A1 discloses a bicycle transmission on the pedal axle, which has a planetary gear. The gear ratio of the planetary gear can be varied by a user by adjusting the power distribution between two electric motors.
[0005] Document EP 2 841 328 B1 discloses a drive unit for a bicycle with a first and a second electric motor and a planetary gear. Document DE 10 2013 012 208 B4 discloses an electric drive system for a human-powered vehicle.
[0006] EP 3 395 663 A1 discloses all features of the preamble of claim 1.
[0007] The devices and methods disclosed in the known prior art documents each result in indirect handling of the bicycle when the user applies pedaling force to the bicycle pedals. In particular, the cyclist perceives the resistance of rotation of the pedal cranks as too low when their pedaling force increases, since the control of the motors is delayed compared to the moment of increased pedaling force on the pedals. In particular, at high rider torques, a perceptible slippage of at least one rotor of at least one of the respective electric motors regularly occurs, since the user's rider torque is not directly supported by the drive wheel or another bicycle component such as the frame or the housing of the drive device.
[0008] Indirect riding feel or indirect riding behavior is therefore understood as a low resistance of the pedals to the application of pedal force by the cyclist and a slow reaction of the drive device to changes in pedal force or to a change in the speed of the pedal axis.
[0009] The object of the present invention is to improve a bicycle transmission that can be switched electrically by means of an electric motor, in particular to produce a more direct riding behavior of the bicycle. Disclosure of the invention
[0010] The above object is achieved according to the invention according to independent claims 1, 13 and 26.
[0011] The invention relates to a method for controlling a drive device of a bicycle according to claim 1.
[0012] The method according to the invention comprises detecting a rotational speed of the pedal axle. The detection of the rotational speed of the pedal axle is particularly configured to detect a change in the rotational speed of the pedal axle, advantageously within a time period of less than or equal to twenty, ten, or five milliseconds, or of less than or equal to one millisecond. For this purpose, the rotational speed of the pedal axle is advantageously detected by means of at least one rotational speed sensor, for example, by means of an incremental encoder or a continuously operating measuring system of the drive device, wherein the rotational speed sensor for detecting the rotational speed of the pedal axle is connected to the pedal axle, in particular by means of a step-up gear stage.Subsequently, a servo motor speed is generated by the servo electric motor as a function of the detected speed of the pedal axle for setting a gear ratio of the planetary gear between the pedal axle and the output pinion, in particular as a function of a currently set servo ratio between the pedal axle and the output pinion or as a function of the currently set gear ratio. When generating the servo motor speed, the servo motor speed of the servo electric motor is adjusted according to the invention within a time period of less than or equal to twenty milliseconds after a change in the detected speed. In other words, the servo motor speed is advantageously adjusted quickly, i.e. within a time period of less than or equal to twenty milliseconds, to a sudden change in the cyclist's pedaling force or a sudden change in the speed of the pedal axle.Preferably, the actuator motor speed is adjusted within a time period of less than or equal to ten milliseconds, within a time period of less than or equal to five milliseconds, or within a time period of less than or equal to one millisecond after a change in the detected speed. This method prevents the rotor of the actuator electric motor from slipping even when a greater pedaling force is suddenly applied to the bicycle pedals or when the speed of the pedal axle changes abruptly, thus creating a direct riding experience for the cyclist.
[0013] Direct riding feel or direct riding behavior refers to the pedals' high resistance to the cyclist's application of pedaling force and the drive system's very rapid response to changes in pedaling force or to changes in the speed of the pedal axis. Furthermore, the gear ratio, which can be adjusted using the servo electric motor, advantageously reduces the maintenance effort required for adjustment and maintenance compared to a conventional derailleur system.
[0014] Furthermore, an actuating ratio between the detected speed of the pedal axle and the actuating motor speed of the actuating electric motor is advantageously adjustable, so that the gear ratio of the planetary gear between the pedal axle and the output pinion can be electrically varied or adjusted. This adjustment of the gear ratio or actuating ratio takes place, in particular, continuously or alternatively, in discrete steps. The method further results in an adjustment of the actuating ratio or a gear ratio that is virtually uninterrupted in the train and switchable under load, resulting in a direct driving feel when switching a gear ratio or a gear. Furthermore, the method advantageously enables an electrical change of a gear ratio, which takes place particularly quietly and virtually wear-free.
[0015] In a particularly preferred embodiment, when generating the actuating motor speed, the actuating ratio between the detected speed of the pedal axle and the actuating motor speed of the actuating electric motor is kept constant for at least a quarter of a revolution of the pedal axle, in particular with a tolerance of less than or equal to twenty percent. This advantageously results in a constant transmission ratio between the pedal axle and the output pinion during this time period, i.e., during at least a quarter of a revolution of the pedal axle. In particular, the set ratio between the detected speed of the pedal axle and the actuating motor speed is kept constant for at least half a revolution of the pedal axle, or particularly preferably for at least one revolution of the pedal axle, in particular with a tolerance of less than or equal to twenty percent.The permissible tolerance or deviation from the constant actuation ratio depends on the ratio between the electric actuator and the first input component of the planetary gear system, in particular on the ratio of the speed reduction gear. This results in a direct riding experience for the cyclist, as the rotor of the electric actuator cannot rotate away from the cyclist's applied cadence for a period longer than one revolution of the pedal axis, and there is a constant resistance of the pedals against the rider's pedaling force. Furthermore, this design results in a riding behavior when the cyclist pedals or pedals that is similar to the riding behavior of conventional bicycles with mechanical derailleurs.
[0016] In one embodiment of the invention, it is provided to detect a cyclist's input regarding a desired gear ratio between the pedal axle and the output pinion. The cyclist's input regarding a desired gear ratio can be made or set, for example, using a twist grip on the bicycle handlebars. Subsequently, the actuating ratio between the detected speed of the pedal axle and the actuating motor speed of the actuating electric motor is adjusted depending on the cyclist's detected input. This advantageously results in a manually switchable gear ratio between the pedal axle and the output pinion or the planetary gear, wherein the gear ratio is switched manually, in particular in discrete steps.
[0017] In a further embodiment of the invention, the actuating ratio between the detected speed of the pedal axle and the actuating motor speed of the actuating electric motor is adapted depending on the detected speed of the pedal axle. In other words, the gear ratio is advantageously changed automatically depending on the detected speed of the pedal axle of the bicycle or the current cadence of the cyclist or the current pedaling frequency of the cyclist. The actuating ratio is adjusted in particular if the detected speed falls below a lower speed threshold or the detected speed exceeds an upper speed threshold. In other words, the advantage results that the gear ratio is adjusted semi-automatically or automatically depending on the current cadence or the current pedaling frequency of the cyclist.Preferably, the gear ratio is increased when the cadence exceeds the upper speed threshold, which is, for example, in a range of 100 to 150 revolutions of the pedal axis per minute, and / or the gear ratio is decreased when the cadence falls below the lower speed threshold, which is, for example, in a range of less than or equal to 70 revolutions of the pedal axis per minute. This automatic adjustment of the actuation ratio or the gear ratio of this further embodiment results in a direct riding experience for the cyclist.
[0018] In a further embodiment of the invention, provision is made for detecting a rider torque at the pedal axle, for example, using a torque sensor. The torque sensor preferably detects an inverse magnetostrictive effect at the pedal axle or at a shaft connected to the pedal axle in a rotationally fixed manner. In this embodiment of the invention, provision is made for adjusting the actuating ratio between the detected speed of the pedal axle and the actuating motor speed of the actuating electric motor depending on the detected rider torque. Since the actuating ratio represents the transmission ratio of the planetary gear between the pedal axle and the output pinion, in this embodiment the transmission ratio or the actuating ratio is advantageously adjusted semi-automatically or automatically depending on the detected rider torque.Preferably, the gear ratio is adjusted when the detected driver torque falls below a lower driver torque threshold or the detected driver torque exceeds an upper driver torque threshold. Particularly preferably, the gear ratio is increased when the detected driver torque falls below a lower driver torque threshold and decreased when the detected driver torque exceeds an upper driver torque threshold. This automatic adjustment of the gear ratio or gear ratio results in a direct riding experience for the cyclist.
[0019] Furthermore, in one embodiment of the invention, it can be provided that a bicycle speed and / or an incline of a route are detected. The actuating ratio between the detected speed of the pedal axle and the actuating motor speed of the actuating electric motor is then adjusted depending on the detected bicycle speed and / or the detected incline of the route. This results in the advantage of a speed- and / or incline-dependent, semi-automatic or automatic adjustment of the actuating ratio or the gear ratio. For example, when the bicycle is traveling downhill on an incline of the route, the gear ratio is automatically shifted to a high gear ratio depending on the current speed of the bicycle.The automatic adjustment of the actuation ratio or the gear ratio of this design results in a direct riding experience for the cyclist, since the cyclist is provided with a resistance adapted to the speed of the bicycle against the application of pedal force, which forces the bicycle to react to the cyclist's pedal force even at high speeds.
[0020] In one embodiment of the invention, if a standstill of the bicycle is detected as a function of a detected speed, a detected position of the bicycle, and / or a detected wheel speed of the bicycle, the actuating ratio is set to a predetermined starting target value. This advantageously sets a gear ratio of the planetary gear between the second input component, or the pedal axle, and the output component, or the output pinion, which creates a direct riding feel when starting a bicycle ride, or whereby the rider's torque is effectively supported by the actuating electric motor when starting a ride from a stationary bicycle.
[0021] It can be provided that, when adjusting the actuating ratio, the actuating ratio is selected from a predefined list of discrete values, with these discrete values each representing different predefined gear ratios. Preferably, the predefined gear ratios between the pedal axle and the output pinion are in a range between 0.5 and 20, particularly preferably in a range between 1 and 10, with the discrete values from the predefined list representing, for example, 3 to 30 gradations within these gear ratio ranges. This design allows the actuating ratio to be adjusted with little computational effort from a control unit, i.e., very quickly, thus enabling a very direct driving behavior.
[0022] In a further development, it can be provided that the actuating ratio is adjusted such that the rotational speed of the pedal axle is continuously regulated to a target rotational value or a target rotational value range, in particular when continuous application of pedal force over several revolutions of the pedal axle is detected, wherein the target rotational value is in the range or the target rotational value range is particularly preferably between 60 and 100 revolutions per minute. In other words, in this further development, the transmission ratio is advantageously continuously changed by adjusting the actuating ratio, so that, regardless of the wind or an incline of the route, a rotational speed of the pedal axle results which advantageously represents the target rotational value, which can be selected in particular by the cyclist via input.Advantageously, the adjustment ratio to the target rotation value or the target rotation value range is continuously determined and adjusted or set after, for example, every half rotation of the pedal axis. This results in a very consistent load for the cyclist. Furthermore, the result is a direct and predictable riding experience.
[0023] In a preferred further development of the method, at least one current pedal crank position is detected. Advantageously, a pedal crank is connected to the pedal spindle at each end of the pedal spindle in a rotationally fixed manner, and the pedal cranks are offset by 180° relative to the pedal spindle. The adjustment of the actuation ratio is then additionally performed depending on the detected current pedal crank position. In particular, the actuation ratio is only adjusted at a time when an angle between the detected current pedal crank position and an upper or lower pedal crank position is within a range of less than or equal to 30°.Particularly preferably, the actuating ratio is only adjusted at a time when the magnitude of the angle between the detected current pedal crank position and the upper or lower pedal crank position is in a range of less than or equal to 10°, in particular in a range of less than or equal to 5°. At other pedal crank positions, the actuating ratio is advantageously not adjusted or kept constant. The course of a pedal force applied by the cyclist during a rotation or revolution of the pedal axis is not uniform; instead, so-called dead points exist for the upper and lower pedal crank positions during the pedal axis rotation, which dead points are characterized by a low pedal force. As a result of this preferred continuation of the method, the actuating ratio is therefore only adjusted when the cyclist applies no or hardly any pedal force and thus does not notice the change in the actuating ratio.By adjusting the ratio depending on the detected current pedal crank position in the upper or lower pedal crank position range, the result is a seamless change in the gear ratio that can be switched under load. This creates a very direct driving experience.
[0024] In a preferred embodiment of the method, a rider torque at the pedal axle is detected in a further step, wherein the rider torque represents the cyclist's pedaling force. Subsequently, a further motor torque is generated at the pedal axle by means of a drive electric motor to assist the cyclist's power as a function of the detected rider torque. The drive electric motor is advantageously connected to the output component of the planetary gear system or to the second input component of the planetary gear system by means of a further speed reduction gear. Alternatively, the drive electric motor is arranged on a front or rear wheel hub of the bicycle, i.e., advantageously spatially separate from the pedal axle.This preferred embodiment of the method results in a multitude of technical advantages, in particular, it results in an electrically assisted bicycle or an electric bicycle that is configured to assist the rider using additional motor torque. For example, in this embodiment, the cyclist can negotiate an incline on a route at a higher speed or cover any distance in a shorter time with reduced effort or without additional physical exertion. Furthermore, the cyclist's power assistance by means of the drive electric motor can be better coordinated or adjusted depending on the set gear ratio, resulting in a more pleasant riding experience, particularly when shifting gear ratios.In particular, in this design, the additional motor torque is generated depending on a change in the gear ratio or the adjustment of the actuating ratio to generate the actuating motor speed of the actuating electric motor, resulting in a particularly desirable riding experience for the cyclist when shifting gears. If the drive electric motor is mounted on a front or rear wheel hub, the required installation space for the drive device on the pedal axle is advantageously reduced, making the drive device less visually noticeable to an observer in the area of the pedal axle.
[0025] Preferably, it can further be provided that an input from the cyclist regarding a desired generator operation or a desired braking operation is made. This input can also represent a desired emergency braking in the event of a detected emergency situation, for example a detected impending impact. Alternatively or additionally, a current charge level of a battery of the bicycle is recorded. Alternatively or additionally, an incline of the route and / or a distance to objects in the vicinity of the bicycle can be recorded, the latter being carried out, for example, by means of a distance sensor, in particular by means of a camera, an ultrasonic sensor, a lidar sensor and / or a radar sensor. In a further step, in this embodiment, a speed of the bicycle is recorded.The actuator electric motor and / or the drive electric motor are then set to a generator operating mode depending on the detected input from the cyclist for generator operation and / or depending on the detected battery charge level and / or depending on the detected gradient of the route and / or depending on the detected distance to objects in the bicycle's vicinity and depending on the detected speed of the bicycle. This embodiment advantageously allows energy to be recovered during a downhill ride and / or the bicycle to be braked. This embodiment also advantageously enables cost-effective and effective automatic braking up to emergency braking of the bicycle, which can be carried out, for example, from the normal operating mode of the method depending on an emergency situation detected based on the detected distance to objects in the surroundings.This design can also be extended to support an anti-lock braking system for the front or rear wheel, as the braking effect can be set to non-lock using the servo electric motor and / or the drive electric motor. When set to generator mode, the pedal axis is specifically fixed. This prevents the pedals or pedal cranks from rotating in generator mode, making riding in generator mode comfortable and / or less prone to injury for the cyclist.
[0026] In a further development of the method, an input from the cyclist for a desired manual operation without electrical assistance is recorded. Alternatively or additionally, a current charge level of a battery module of the bicycle is recorded. Alternatively or additionally, in this development, the current speed of the bicycle is recorded. Subsequently, the first input component of the planetary gear is fixed in a rotationally fixed manner to the housing of the drive unit, in particular by means of a brake disc connected in a rotationally fixed manner to the first input component, depending on the recorded input from the cyclist for a desired manual operation and / or depending on the recorded current charge level of the battery module and / or depending on the recorded speed of the bicycle, in particular by means of a brake.This further extension advantageously results in a direct gear between the pedal axle and the output pinion, allowing the bicycle to be propelled even without the servo electric motor operating. Furthermore, it can be provided to adjust this direct gear when starting a ride or to fix the first input component to the housing, thus advantageously resulting in a very direct riding feel when starting a ride or when the rider's torque is high.
[0027] The invention also relates to a drive device for a bicycle, wherein the drive device comprises a planetary gear, an electric servomotor, and a speed reduction gear. The electric servomotor is connected to a first input component of the planetary gear by means of the speed reduction gear, and a pedal axle is connected to a second input component of the planetary gear in a rotationally fixed or meshing manner. An output component of the planetary gear, different from the input components, is connected to an output pinion of the drive device, in particular in a rotationally fixed manner. Furthermore, a control unit of the drive device is configured to carry out the method according to the invention.Thus, the control unit is advantageously configured to detect the rotational speed of the pedal axle using at least one rotational speed sensor and to control the servo electric motor as a function of the detected rotational speed of the pedal axle to generate a servo motor speed for setting a transmission ratio between the pedal axle and the output pinion, wherein the servo motor speed is adjusted within a period of twenty milliseconds after a change in the detected rotational speed. The output pinion is connected in particular by means of a chain or preferably by means of a toothed belt to the hub of a rear wheel of the bicycle, whereby the drive device is configured to transmit a rider torque applied to the pedal axle to the rear wheel to drive the bicycle. The drive device is advantageously compact or has a small installation space.A further advantage is that the drive system provides the cyclist with a direct riding experience. In other words, the drive system advantageously comprises an electrically switchable planetary gear system, whereby a gear ratio change is electrically controlled and thus occurs particularly quietly and with virtually no wear. Furthermore, an electrically adjustable gear shift system advantageously results, which enables manual, semi-automatic, and / or automatic adjustment of a gear ratio of the planetary gear system between the pedal axle and the output pinion of the drive system.
[0028] Preferably, the control unit is configured to maintain a constant control ratio between the detected rotational speed of the pedal axle and the control motor speed for at least a quarter of a rotation of the pedal axle. In particular, the control ratio is maintained constant for at least half a rotation of the pedal axle, and particularly preferably for at least one rotation of the pedal axle. This design of the drive device enhances the cyclist's direct riding experience while riding.
[0029] In a particularly preferred embodiment of the drive device, the speed sensor has at least one mechanical, optical, inductive and / or electrical incremental encoder or a continuously operating measuring system for detecting the speed of the pedal axle or for detecting a change in speed or angle of the pedal axle. Preferably, the speed sensor, in particular the incremental encoder or the continuously operating measuring system for detecting the speed, is configured to detect a change in an angular velocity for the pedal axle rotation or a change in speed within twenty milliseconds, in particular within ten milliseconds and particularly preferably within one millisecond. This design of the drive device results in reliable, very fast detection of the speed and thus a more direct riding experience for the cyclist.
[0030] In a further development, the incremental encoder or the continuously operating measuring system of the drive device for detecting the speed of the pedal axle is connected to the pedal axle via a high-speed gear stage. This extension allows a change in the speed of the pedal axle to be detected particularly quickly and the speed and / or a change in speed to be detected very precisely, so that the actuator motor speed of the actuator electric motor can be adjusted particularly quickly after a change in the detected speed, thus reliably preventing the rotor of the actuator electric motor from slipping in all riding situations. This results in a particularly direct riding experience for the cyclist.
[0031] In a preferred embodiment of the drive device, the planetary gear is arranged coaxially around the pedal axis. In this preferred embodiment, the pedal axis is connected in a rotationally fixed manner to the planet carrier of the planetary gear. The servo electric motor is connected via the speed reduction gear, meshing with an external toothing of the ring gear of the planetary gear. The sun gear of the planetary gear is further arranged in a rotationally fixed manner on a hollow output shaft running coaxially around the pedal axis. This hollow output shaft is connected in a rotationally fixed manner to the output pinion of the drive device. This design results in a very compact and lightweight drive device.
[0032] In a further embodiment, the control unit is configured to detect a cyclist's input regarding a desired gear ratio between the pedal axle and the output pinion using a gear selection device. The gear selection device is arranged in particular on the handlebars of the bicycle and is connected to the control unit, for example, by means of a cable or wirelessly using a radio protocol, in particular via Bluetooth. The control unit is further configured to adjust the actuating ratio between the detected speed of the pedal axle and the actuating motor speed depending on the cyclist's detected input. This embodiment advantageously configures the control unit to change a gear ratio of the planetary gear according to a detected manual input from the cyclist for a desired gear change.
[0033] In a further embodiment, the control unit is configured to adjust the control ratio between the detected rotational speed of the pedal axle and the control motor speed depending on the detected rotational speed and / or depending on a driver torque on the pedal axle detected by a torque sensor. Preferably, the control unit is configured to adjust the control ratio when the detected rotational speed falls below a lower rotational speed threshold, and / or when the detected driver torque falls below a lower driver torque threshold, and / or when the detected rotational speed exceeds an upper rotational speed threshold, and / or when the detected driver torque exceeds an upper driver torque threshold.This design advantageously results in a semi-automatic or automatic adjustment of the gear ratio or the actuation ratio, which makes the cyclist's ride comfortable and the riding experience very direct.
[0034] In a further advantageous embodiment, the control unit is configured to detect the speed of the bicycle. The control unit detects the speed in particular using a speed sensor. The speed sensor comprises, for example, a reed sensor on the front or rear wheel and / or a position sensor for a global navigation satellite system. Alternatively or additionally, the control unit is configured to detect the gradient of a route, in particular using an inertial measuring unit. Furthermore, in this embodiment, the control unit is configured to adapt the control ratio between the detected rotational speed of the pedal axle and the control motor speed depending on the detected bicycle speed and / or the detected gradient of the route.This design advantageously achieves a semi-automatic or automatic adjustment of the gear ratio or the actuating ratio or improves a semi-automatic or automatic adjustment of the gear ratio or the actuating ratio, making the cyclist's ride particularly comfortable and the riding experience very direct.
[0035] It can further preferably be provided that the control unit of the drive device is configured to detect at least one current pedal crank position. This detection of the pedal crank position takes place in particular by means of a pedal crank position sensor and / or by means of a mechanical, optical, inductive and / or electrical incremental encoder and / or by means of a continuously operating measuring system for detecting an angular change of the pedal axis and / or by means of rotor position sensors of the drive electric motor. The control unit is further configured to adapt the actuation ratio depending on the detected current pedal crank position.In this embodiment of the invention, an adjustment of the actuating ratio takes place in particular only in the area of an upper or lower pedal crank position, so that the cyclist can advantageously hardly perceive the adjustment of the actuating ratio by changing the actuating motor speed due to the reduced pedal force in this area of the upper or lower pedal crank position and thus a direct driving feeling is maintained even when shifting gears or when adjusting the actuating ratio.
[0036] In a preferred development, the drive device has a further drive electric motor. The drive electric motor is connected to the output component of the planetary gear system or to the second input component of the planetary gear system, in particular in each case by means of a further speed reduction gear. A motor freewheel can advantageously be arranged between the drive electric motor and the planetary gear system, wherein the motor freewheel is configured to engage the speed reduction gear so that it can rotate freely relative to the pedal axis if the speed of the pedal axis is less than the drive motor speed of the drive electric motor or if the rotation direction of the pedal axis is negative. Alternatively, the drive electric motor is arranged on a front wheel hub or on a rear wheel hub of the bicycle.In this preferred development, the drive device is further configured, in particular by means of the control unit, to detect a rider torque at the pedal axle using a torque sensor. The drive electric motor is further configured, in particular by means of the control unit or by means of a further control unit of the drive electric motor, to be controlled as a function of the detected rider torque. This preferred development results in an electric bicycle that is advantageously configured to generate an additional motor torque to assist the cyclist. This allows the cyclist, for example, to reduce their manual pedaling force or the rider torque while maintaining a constant bicycle speed, since part of the power from the drive electric motor is generated by the additional motor torque.This preferred continuation of the drive device makes the cyclist’s ride particularly comfortable.
[0037] In a further embodiment of the preferred development of the drive device, the rotor position sensors of the drive electric motor are used as speed sensors for detecting the speed of the pedal axle. In other words, in this embodiment, the at least one speed sensor for detecting the speed of the pedal axle comprises the rotor position sensors of the drive electric motor. Since the drive electric motor advantageously rotates at a fixed speed ratio to the pedal axle and is operated at high revolutions per minute, the rotor position sensors can advantageously detect the speed of the pedal axle very precisely. This results in a very direct riding experience for the cyclist.
[0038] Preferably, the drive device, in particular by means of the control unit, is configured to detect the speed of the bicycle using a speed sensor. In this embodiment, the electric drive motor is also configured to be controlled depending on the detected bicycle speed. This results in the advantages that the starting behavior at the start of a ride and the locking behavior of the drive device at speeds greater than a predetermined maximum speed of the bicycle can be optimized for a direct riding experience.
[0039] Furthermore, in another embodiment, the control unit is configured to detect an input from the cyclist regarding generator operation and / or an incline of the route. The incline is detected in particular by means of an inertial measuring unit. In this embodiment, it is further provided that the control unit is configured to detect a speed of the bicycle using a speed sensor. Furthermore, in this embodiment, the control unit is configured to switch the actuator electric motor and / or the drive electric motor into a generator operating mode or into a braking mode, or to activate the generator operating mode, depending on the detected input from the cyclist regarding generator operation and / or the detected incline of the route and depending on the detected speed of the bicycle.The control unit is particularly configured to fix the pedal axis in the activated generator operating mode, thereby preventing unintentional rotation of the pedal cranks in generator operating mode. This design advantageously allows the drive device to convert kinetic energy of the bicycle and / or the cyclist into electrical power, with the generated electrical power being stored in a battery of the bicycle and resulting in longer power assistance for the cyclist. This design also advantageously enables braking assistance or automatic braking of the bicycle, for example, in an emergency braking situation.
[0040] Furthermore, it can be provided that the control unit is configured to detect an input from the cyclist regarding a desired manual operation without electrical assistance and / or a current charge level of a battery module of the bicycle. The control unit can then further be configured to fix the first input component of the planetary gear, in particular by means of a brake disc connected in a rotationally fixed manner to the first input component, depending on the detected input from the cyclist regarding a desired manual operation and / or depending on the detected current charge level of the battery module, in particular by means of a brake. This design enables direct and effective driving of the rear wheel by means of the drive device without electrical power consumption, even when the charge level of the battery module is low or when energy savings are desired.
[0041] The invention further relates to a bicycle with the drive device according to the invention.
[0042] Further advantages will become apparent from the following description of embodiments with reference to the figures. Figure 1 : Bicycle with a drive device with servo electric motor Figure 2 : Bicycle with drive device with additional drive electric motor Figure 3 : Bicycle with a drive device, wherein a drive electric motor is arranged on the rear wheel hub Figure 4 : Schematic gear structure of a drive device with servo electric motor Figure 5 : Schematic gear structure of a drive device with additional drive electric motor Figure 6 : Flowchart of the method for controlling a drive device
[0043] In Figure 1A bicycle 100 with a drive device 200 having a servo electric motor 210 is shown schematically and in a side view. The bicycle 100 has a front wheel 101 and a rear wheel 102, wherein the rear wheel 102 is driven at the rear wheel hub 103 by means of a connecting element 107, in particular a toothed belt or a chain, and by means of the drive device 200 by the cyclist's pedaling force on the pedals 104. The pedals 104 are connected to pedal cranks 105, which in turn are connected to different ends of a pedal axle 106.The drive device 200 is configured to transmit a rider torque acting on the pedal axle 106 by means of a switchable planetary gear to an output pinion 108, which is in direct engagement with the connecting element 107 for driving the bicycle 100, wherein a gear ratio of the planetary gear is varied, changed, or adjusted by means of the servo electric motor 210. The gear ratio of the planetary gear of the drive device 200 can be selected or adjusted, for example, by means of a gear selection means 230 and / or automatically as a function of the detected rotational speed of the pedal axle 106 and / or a detected rider torque. The gear selection means 230 is preferably arranged on the handlebar 110 of the bicycle 100. The setting of a gear ratio of the planetary gear orA gear is shifted by adjusting or changing a control ratio between the rotational speed of the pedal axle 106 and a generated actuator motor speed of the actuator electric motor 210. In other words, the drive device 200 is configured to electrically control a transmission ratio of the planetary gear by adjusting an actuator motor speed. To supply energy to the drive device 200, in particular to the actuator electric motor 210, a battery module 300 is additionally arranged on the bicycle 100. The electrical consumption of the actuator electric motor 210 is low compared to the electrical consumption of a drive motor of an electric bicycle, which is why the battery module 300 can be comparatively small. The battery module 300 is electrically connected to a control unit of the drive device 200 and the actuator electric motor 210, in particular by means of a cable 310.
[0044] A gear ratio i between two meshing gears is understood as the ratio between a speed n input of a first component or an input component and a speed n output of a second component or an output or output component, see equation (1). In other words, the first component drives the second component with a speed n input and a torque M input, whereby a changed speed n output and a changed torque M output result at the second component depending on the gear ratio i, see equation (1). For two meshing gears, the gear ratio i is generally dependent on the number of teeth Z input of the first component and the number of teeth z output of the second component, see equation (1). i = n Eingang n Ausgang = z Ausgang z Eingang = M Ausgang M Eingang
[0045] In principle, planetary gears can have three rotating components if none of the components is fixed to a housing or frame. Planet gears of the planetary gear are generally arranged between a sun gear and an outer ring gear and on a planet carrier so that they can rotate with respect to engagement with the ring gear and sun gear and are fixed or arranged on the planet carrier so that they cannot rotate with respect to revolution around the sun gear. A generally valid relationship between the speeds of the various components or gears of a planetary gear and the number of teeth of these components is shown in equation (2), where n H is the speed of the ring gear, z H is the number of teeth on the ring gear, n T is the speed of the planet carrier, n S is the speed of the sun gear and z S is the number of teeth on the sun gear.Equation (2) thus reveals the dependence of a respective gear ratio between two different components of the planetary gear on the speed of the other rotating component of the planetary gear, where one of the two different components represents a drive or input and the other represents an output. n S = n T ⋅ 1 + i 0 − n H ⋅ i 0 , i 0 = z H z S
[0046] For example, a gear ratio between the planet carrier as input and the sun gear as output is influenced by the speed of the ring gear, wherein, for example, the speed of the ring gear can be changed by means of the servo electric motor 210 of the drive unit 200 shown above through a generated servo motor speed. For this purpose, the ring gear has, for example, external teeth which, for example, mesh with a speed reduction gear, wherein the speed reduction gear is connected in meshing engagement with the rotor of the servo electric motor. Thus, the gear ratio i between the planet carrier and the sun gear of a planetary gear can be adjusted by changing the servo motor speed of the servo electric motor, which is connected in meshing engagement with the ring gear by means of a speed reduction gear.
[0047] For example, for a desired or selected gear ratio between the pedal axle as the second input component and the sun gear as the output component of 2, equation (3) applies. With a stationary gear ratio of, for example, i 0 = 10, equation (4) applies. Furthermore, for example, there is a speed reduction gear between the servo electric motor and the ring gear as the first input component with a gear ratio of 40. Thus, for the gear ratio between the pedal axle and the sun gear of 2, the motor speed n M depends on the speed of the planet carrier n T which is connected in a rotationally fixed manner to the pedal axle, according to equation (5). In other words, for a fixed gear ratio, the motor speed must be continuously adjusted to the speed of the pedal axle or the cyclist's cadence. In order for the cyclist not to find this disturbing, the motor speed must be adjusted very quickly.To achieve this, the speed of the pedal axis must be measured with high precision, and the control of the electric motor must also be adjusted quickly. n T n S = 2 → n S = n T 2 n H = n T ⋅ 1 + i 0 − 1 2 ⋅ 1 i 0 n H = n T ⋅ 1 , 05 n M n H = 40 → n M = 42 ⋅ n T
[0048] In Figure 2 a bicycle 100 with a drive device 200 with servo electric motor 210 is shown schematically in a side view, wherein the drive device 200 is opposite Figure 1additionally has at least one drive electric motor 240. The drive electric motor 240 is configured to generate an additional motor torque as a function of a detected rider torque and / or as a function of a detected rotational speed of the pedal axis or a detected cadence. Thus, the drive device with the drive electric motor 240 creates an electric bicycle 100 for power assistance of the cyclist with a planetary gear system that can be electrically controlled by means of the servo electric motor 210 as a switchable gearshift. The drive device 200 of Figure 2 has a larger installation space than the drive device due to the additional drive electric motor 240 Figure 1 The drive device 200 from Figure 2 one opposite the drive device Figure 1A preferred embodiment of the invention, since an electric bicycle as bicycle 100 already has a sufficiently large battery module 300 for power assistance to supply energy to the servo electric motor 210, wherein the battery module 300 is electrically connected to the drive device 200, for example, by means of a cable 310. The energy consumption of the servo electric motor 210 for adjusting the gear ratio of the planetary gear of the drive device is low compared to the energy consumption of the drive electric motor 240 for power assistance to the cyclist. Provision can be made for the servo electric motor 210 and the drive electric motor 240 to have a common control unit or separate control units.
[0049] In Figure 3a bicycle with a drive device 200 with servo electric motor 210 is shown schematically in a side view, wherein the drive device 200 has a drive electric motor 240, wherein this drive electric motor 240 is opposite the drive device from Figure 2 is arranged on the rear wheel hub 103 of the bicycle 100. In other words, the drive electric motor is made of Figure 3 a wheel hub motor. The design of the drive device 200 from Figure 3 is visually less conspicuous than the design of the drive device 200 from Figure 2 , as they are located in the mid-engine position like the drive device 200 from Figure 1smaller. To supply power to the drive device 200, in particular to the servo electric motor 210 and the drive electric motor 240, a battery module 300 is arranged on the bicycle 100. The battery module 300 is electrically connected to the control unit of the drive device 200 and to the servo electric motor 210 and / or the drive electric motor 240, for example, by means of a cable 310 each. It can be provided that the drive electric motor 240, designed as a wheel hub motor, has its own separate control unit and / or a separate battery module 300.
[0050] In Figure 41 shows a schematic cross-sectional view of a transmission structure of a drive device 200 with an electric servo motor 210. The drive device has a housing 201. The pedal axis 106 is rotatably fixed to the housing by means of bearings 202, for example ball bearings, and extends through an opening in the housing 201 and through the housing 201. A planetary gear 220 arranged coaxially around the pedal axis 106 is arranged within the housing 201. The output pinion 108 of the drive device 200 is arranged in a rotationally fixed manner on an output hollow shaft 270 arranged coaxially to the pedal axis 106. The output hollow shaft 270 is rotatably fixed to the housing 201 by means of bearings 203 relative to the pedal axis 106 and rotatably fixed to the housing 201 by means of bearings 204 and extends through one of the openings in the housing 201.The output pinion 108 is designed to drive the connecting element 107, in particular the toothed belt or chain, thereby generating a drive for the rear wheel 102 of the bicycle. In this exemplary embodiment, the sun gear 221 of the planetary gear 220 is connected in a rotationally fixed manner to the hollow output shaft 270 as an output component. The planetary gear 220 further comprises, as a first input component, a ring gear 224 with external teeth. The external teeth of the ring gear 224 are connected in engagement to the servo electric motor 210 by means of a speed reduction gear 260. The planet gears 222 mesh or are arranged in engagement with and between the sun gear 221 and the ring gear 224 of the planetary gear 220. The speed reduction gear 260 can be single-stage or multi-stage, for example, as shown in FIG. Figure 4shown, two-stage. The second input component of the planetary gear 220 is the planet carrier in this embodiment. The planet carrier 223 is connected in a rotationally fixed manner to a plurality of planetary gears 222, in particular to three planetary gears 222, and to the pedal axle 106. Furthermore, the drive device 200 has a speed sensor 285. The speed sensor 285 detects the speed of the pedal axle 106, for example, by photoelectric scanning or magnetic scanning. For example, the drive device 200 has a slotted disk 283 for detecting the speed, which is connected to the pedal axle 106 by means of an optional high-drive gear stage 280. The optional high-drive gear stage 280 has the Figure 4illustrated first larger gear 281 and a second smaller gear 282, wherein the slotted disc 283 is connected in a rotationally fixed manner to the second smaller gear 282, so that the disc 283 rotates at a sensor speed that is higher than that of the pedal axle and defined by a fixed gear ratio. In other words, the sensor speed of the disc 283 is proportional to the speed of the pedal axle 106. The speed sensor 285 is thus configured to detect a speed that represents the speed of the pedal axle 106. The speed sensor 285 further comprises, for example, a light-emitting diode and at least two slightly offset photodetectors, wherein the disc 281 is arranged between the light-emitting diode and the photodetectors.The speed sensor 285 is configured to precisely detect the speed of the pedal axle 106. Advantageously, the speed sensor 285 has an accuracy of at least 1000 increments per revolution, preferably at least 2000 increments per revolution, and particularly preferably at least 4000 increments per revolution. The speed sensor 285 can additionally comprise a reed sensor for detecting a complete revolution of the pedal axle 106, wherein, for example, a magnet for detecting the reed signal is arranged on the pedal cranks 105 and / or on the first larger gear 281 and / or on the disc 281. The cyclist's pedaling forces on the pedals, which are rotationally fixedly connected to the pedal cranks 105 and the pedal axle 106, result in a rider torque and a speed of the pedal axle 106.The rotational speed and driving torque are transmitted by means of the planet carrier 223 and the planets 222 to the sun gear 221 of the planetary gear set 220 and finally to the output pinion 108 and the connecting element 107. The transmission ratio between the planet carrier 223 and the sun gear 221 can be electrically adjusted by means of the servo electric motor 210 by generating a servo motor speed as a function of the detected rotational speed of the pedal axle 106, wherein the control ratio between the rotational speed of the pedal axle 106 and the servo motor speed is preferably constant for at least a quarter of a revolution of the pedal axle. In other words, the servo motor speed continuously follows the detected rotational speed of the pedal axle 106, wherein an adjustment of the servo motor speed is carried out within a period of less than or equal to twenty milliseconds (20 ms) after a change in the rotational speed of the pedal axle 106.A signal from the speed sensor 285, which represents the detected speed, is detected by the control unit 250, and the electric actuator 210 is controlled depending on the detected speed of the pedal axle 106. With a gear ratio between the ring gear 224 and the electric actuator 210 of i=48, the electric actuator 210 should advantageously be able to provide a speed of up to 3600 rpm with a torque of up to 3 Nm, so that the driver's torque is sufficiently reliably supported. Furthermore, the drive device 200 includes an optional brake 225, which is configured to fix an optional brake disc 226, wherein the brake disc 226 is connected in a rotationally fixed manner to the ring gear 224 of the planetary gear or to a rotor of the electric actuator 210.For example, the brake 225 can be activated at bicycle speeds less than or equal to a threshold value to establish a direct gear, which provides the cyclist with a very direct riding experience even with high pedaling force when the bicycle is stationary. Alternatively or additionally, the brake can be activated in the event of a low charge level of the battery module to establish a direct gear. When the brake 225 is activated, the servo electric motor 210 is not controlled.
[0051] In Figure 5 is a to Figure 4 A similar structure of a transmission of the drive device 200 with servo electric motor 210 is shown schematically in cross section. The reference numerals in Figure 5 indicate the same components as in Figure 4 . The drive device 200 from Figure 5 has opposite the drive device 200 Figure 4a slightly modified arrangement of the components relative to each other and additionally an input hollow shaft 510, a torque sensor 520 and a drive electric motor 240 as well as a further speed reduction gear 530 and a motor freewheel 540. In the embodiment of Figure 5The pedal axle 106 is connected in a rotationally fixed manner to the input hollow shaft 510. The input hollow shaft 510 comprises two magnetized or magnetizable regions 511. The magnetization of these magnetized or magnetizable regions 511 can be detected by the torque sensor 520, wherein the detected magnetization of the magnetized or magnetizable regions 511 represents the driver torque. In other words, the driver torque is detected at the input hollow shaft 510 by determining an inverse magnetostrictive effect due to torsion of the input hollow shaft 510. The disc 283 is further connected to the input hollow shaft 510 by means of the optional high-drive gear stage 280, or the first larger gear 281 and the second smaller gear 282, in meshing engagement.The speed sensor is configured to detect the speed of the pedal axle by means of the disk 283, since the speed of the disk 283 or the sensor speed represents the speed of the pedal axle 106. The planet carrier 223 of the planetary gear 220 is connected in a rotationally fixed manner to the input hollow shaft 510 as the second input component of the planetary gear 220. The servo electric motor 210 is connected by means of the speed reduction gear 260 in engagement with the external toothing of the ring gear 224 of the planetary gear 220 as the first input component of the planetary gear 220 and drives the latter. The speed reduction gear 260 can be single-stage or multi-stage, for example, as shown in FIG. Figure 5shown, two-stage. The rotation of the planet carrier 223 and the ring gear 224 drives the planet gears 222 and the sun gear 221 of the planetary gear set 220 as the output component of the planetary gear set. The sun gear 221 is arranged on the hollow output shaft 270 in a rotationally fixed manner and is connected to the output pinion 108 in a rotationally fixed manner. The drive electric motor 240 is also connected to this hollow output shaft 270 by means of a further speed reduction gear 530. A further motor torque generated by the drive electric motor 240 is thus summed at the hollow output shaft 270 with the rider torque of the cyclist and the motor torque of the servo electric motor 210, and the resulting torque of the hollow output shaft 270 is transmitted to the output pinion 108 to drive the bicycle. An optional motor freewheel 540 is advantageously arranged between the speed reduction gear 530 and the hollow output shaft 270.Alternatively, the speed reduction gear 530 can be arranged between the input hollow shaft 510 and the drive electric motor 240, so that the drive electric motor 240 is connected to the input hollow shaft 510 or the additional motor torque generated is transmitted to the input hollow shaft 510. The control unit 250 is configured to control the servo electric motor 210 depending on the detected speed of the pedal axle 106 and / or the drive electric motor 240 depending on the detected driver torque.
[0052] In an alternative embodiment of the drive device, not shown, the drive electric motor 240 is arranged as a wheel hub motor on the rear wheel hub 103 of the rear wheel 102 of the bicycle 100 instead of in the area of the pedal axle 106 or on the output hollow shaft. Figure 5In this embodiment, the housing 201 of the drive device 200 does not have a motor freewheel 540, a further speed reduction gear 540, and a drive electric motor 240, since the latter is arranged as a wheel hub motor on the rear wheel hub 103. Consequently, this alternative embodiment of the drive device 200 requires a drive shaft in the area of the pedal axis that is larger than the drive device of Figure 5 smaller installation space.
[0053] Alternatively to the Figure 4 and Figure 5In the examples shown, it may be provided that other components of the planetary gear set represent the first input component and / or the second input component of the planetary gear set and / or the output component. For example, the planet carrier or the sun gear can also be the first input component of the planetary gear set. In this regard, it is only necessary that the first input component, the second input component, and the output component of the planetary gear set differ from one another.
[0054] During generator operation, at least one component of the planetary gear can be fixed, in particular by means of a brake 225 and a brake disc 226. Preferably, either the servo electric motor 210 and / or the drive electric motor 240 is operated in generator mode. For example, the second input component of the planetary gear 220 or the ring gear 224 of the planetary gear 220 or the output component of the planetary gear 220 or the sun gear 221 of the planetary gear 220 is fixed in a rotationally fixed manner to the housing 201 of the drive device 200. Thus, in this example, the drive electric motor 240 can recover the kinetic energy of the bicycle (either as a wheel hub motor or when arranged in the area of the pedal axle, for example, according to Figure 5). Alternatively or additionally, the pedal axis 106 can be fixed in generator mode. Thus, the pedals do not rotate during generator mode of the servo electric motor 210 and / or the drive electric motor 240.
[0055] In Figure 6A flowchart of the method for controlling a drive device 200 is shown as a block diagram. First, in step 610, the rotational speed of the pedal axle 106 is detected. It can advantageously be provided that in step 610 a variable is detected which represents the rotational speed. For example, in step 610 the angular velocity of the pedal axle 106 or a profile of the angular position of the pedal axle 106 is detected. It can further advantageously be provided that in step 610 a rotational speed of a component of the drive device 200 is detected which represents the rotational speed of the pedal axle 106. In particular, in step 610 the rotational speed of a disk 283 is detected which is connected to the pedal axle in a rotationally fixed manner or is connected to the pedal axle by means of a drive shaft 280 in engagement.The rotational speed of the pedal axle 106 is recorded as accurately as possible in step 610. In particular, for example, the disk 283 has greater than or equal to 1000 passes of increments or slots or countable units per revolution of the pedal axle 106. Particularly preferably, the disk 283 has greater than or equal to 2000 passes of increments or greater than or equal to 4000 passes of increments per revolution of the pedal axle 106.
[0056] Optionally, step 620 may detect a cyclist's input regarding a desired gear ratio between the pedal axle and the output pinion. In another optional step 630, the bicycle speed is detected. In a further optional step 631, a gradient of a route is detected. Furthermore, in optional step 632, a driver torque is detected. Preferably, in the further optional step 640, at least one current pedal crank position is detected, wherein the pedal crank position can advantageously be determined or detected as a function of the detected rotational speed.
[0057] In step 650, a servo motor speed is generated by the servo electric motor as a function of the detected speed of the pedal axle to set a gear ratio of the planetary gear between the pedal axle and the output pinion. The servo motor speed is adjusted in step 650 within a time period of less than or equal to twenty milliseconds after a change in the detected speed of the pedal axle. When generating 650 the servo motor speed, a control ratio exists between the detected speed of the pedal axle and the servo motor speed. This control ratio between the detected speed of the pedal axle and the generated control motor speed of the servo electric motor is advantageously kept constant in step 650 for at least a quarter of a revolution of the pedal axle. Preferably, the control ratio z is kept constant for at least half a revolution of the pedal axle.Particularly preferably, the actuating ratio is kept constant at least during one or more revolutions of the pedal axis.
[0058] In an optional step 660, an adjustment of the actuating ratio between the detected speed of the pedal axle and the actuating motor speed of the actuating electric motor is performed. The adjustment 660 of the actuating ratio optionally occurs as a function of the detected input from the cyclist. Alternatively or additionally, the optional adjustment 660 of the actuating ratio occurs, in particular semi-automatically or automatically, as a function of the detected speed of the pedal axle and / or as a function of the detected rider torque and / or as a function of the detected speed of the bicycle and / or as a function of the detected gradient of the bicycle's route. The actuating ratio is advantageously adjusted in step 660 if the detected speed falls below a lower speed threshold and / or if the detected speed exceeds an upper speed threshold.Alternatively or additionally, the adjustment ratio is advantageously adjusted in step 660 if the detected driver torque falls below a lower driver torque threshold and / or if the detected driver torque exceeds an upper driver torque threshold. Alternatively or additionally, the adjustment ratio is advantageously adjusted in step 660 depending on the detected bicycle speed and / or the detected gradient of the route. It can be provided that, if a standstill of the bicycle is detected depending on a detected bicycle speed, the adjustment ratio is adjusted or set to a predetermined starting target value.
[0059] The ratio can, for example, be a value from a predefined list of discrete values or be selected from the predefined list of discrete values. The discrete values each represent different predefined transmission ratios, with the transmission ratios being in particular between 1 and 10; particularly preferably, the transmission ratios are in particular between 0.5 and 20.
[0060] In an optional continuation, the actuating ratio is adjusted in step 660 such that the rotational speed of the pedal axle is continuously controlled to a target rotational value or a target rotational value range. The target rotational value is, for example, 80 revolutions per minute. The target rotational value range is, for example, between 70 and 100 revolutions per minute. In other words, the method is carried out continuously, wherein the actuating motor speed generated in step 650 is controlled by adjusting the actuating ratio in step 660 such that a continuously adjusted transmission ratio of the planetary gear between the pedal axle and the output pinion results, wherein the resulting transmission ratio causes the cyclist's cadence or the rotational speed of the pedal axle to adapt to or approximate a target rotational value, given a constant pedaling force from the cyclist.
[0061] Particularly preferably, the optional adjustment 660 of the actuating ratio is carried out alternatively or additionally as a function of the detected current pedal crank position, in particular only in the range of an upper or lower pedal crank position with respect to the pedal crank rotation or pedal axis rotation. As a result, the actuating ratio is only adjusted when the cyclist hardly notices this, since in the range of the upper or lower pedal crank position the cyclist's force on the pedals is minimal or the force on the pedals on each leg at the upper or lower pedal crank position each has a zero crossing. A range of an upper or lower pedal crank position with respect to the pedal crank rotation or pedal axis rotation can be defined by the angular deviation from the upper or lower pedal crank position, which is, for example, less than or equal to 20 degrees and in particular less than or equal to 10 degrees.
[0062] In an additional optional step 670, a further motor torque is generated as a function of the detected rider torque on the pedal axle by means of the drive electric motor to assist the cyclist.
[0063] Furthermore, in an optional step 680, it may be provided to detect an input from the cyclist regarding generator operation. In a further optional step 681, a distance of the bicycle from objects in the bicycle's surroundings is detected. Furthermore, a setting 682 of the servo electric motor and / or the drive electric motor to a generator operating mode can be carried out depending on the detected input from the cyclist regarding generator operation and / or the detected distance of the bicycle from objects in the bicycle's surroundings and / or the gradient of the route detected in step 631 and depending on the speed of the bicycle detected in step 630. In this optional embodiment of the invention, kinetic energy of the bicycle can therefore be recovered.During step 682, the pedal axle is fixed in particular to the housing of the drive device, for example by means of a brake disc, which is connected in a rotationally fixed manner to the pedal axle, and a brake.
[0064] Furthermore, in an optional step 690, an input from the cyclist regarding a desired manual operation without electrical assistance is recorded. Alternatively or additionally, in optional step 691, a current charge level of a bicycle battery is recorded. Subsequently, in optional step 692, the first input component of the planetary gear is fixed. The fixing takes place, in particular, depending on the recorded input from the cyclist regarding a desired manual operation and / or depending on the recorded current charge level of the battery, in particular by means of a brake disc and a brake connected in a rotationally fixed manner to the first input component.
[0065] The method is preferably performed continuously. It can optionally be paused if the detected speed of the pedal axle falls below a termination threshold. The method is continued, in particular, with the previous adjustment ratio as soon as a speed is detected again on the pedal axle.
Claims
1. Method for controlling a drive device (200) of a bicycle (100), wherein the drive device (200) comprises a planetary gear (220), an actuating electric motor (210) and a speed reduction gear (260), wherein the actuating electric motor (210) is engagingly connected to a first input component (224) of the planetary gear (220) by means of the speed reduction gear (260) and the pedal axle (106) of the bicycle (100) is connected for conjoint rotation or engagingly to a second input component (223) of the planetary gear (220), and an output component (221) of the planetary gear (220) different from the input components (223, 224) is connected, for conjoint rotation, to an output pinion (108) of the drive device (200), said method comprising the following method steps • detection (610) of a speed of the pedal axle (106), and • generation (650) of an actuating motor speed by means of the actuating electric motor (210) based on the detected speed of the pedal axle (106) in order to set a transmission ratio of the planetary gear (220) between the pedal axle (106) and the output pinion (108), wherein the actuating motor speed is adjusted within a time period of less than or equal to twenty milliseconds after a change in the detected speed of the pedal axle (106) and • wherein the planetary gear (220) is arranged coaxially around the pedal axle (106), • the pedal axle (106) is connected for conjoint rotation to the planetary carrier (223) of the planetary gear (220), • the actuating electric motor (210) is connected engagingly to the hollow shaft (224) of the planetary gear (220) by means of the speed reduction gear (260), wherein the hollow shaft (224) additionally has an external toothing, and • the sun gear (221) of the planetary gear (220) is arranged for conjoint rotation on a hollow output shaft (270) running coaxially around the pedal axle (106) and said hollow output shaft (270) is connected for conjoint rotation to the output pinion (108) of the drive device (200), said method being characterized by the following steps: • detection (690) of an input from the cyclist for desired manual operation without electrical assistance, and / or • detection (691) of a current state of charge of a battery module (300) of the bicycle (100), and • fixing (692) of the hollow shaft (224) of the planetary gear (220) by means of a brake disc (226), which is connected for conjoint rotation to the hollow shaft (224), based on the detected input from the cyclist for desired manual operation and / or based on the detected current state of charge of the battery module (300), by means of a brake (225).
2. Method according to Claim 1, wherein, in the generation (650) of the actuating motor speed, an actuating ratio between the detected speed of the pedal axle (106) and the actuating motor speed of the actuating electric motor (210) is kept constant at least over a quarter rotation of the pedal axle (106).
3. Method according to either of Claims 1 and 2, wherein the following steps are carried out • detection (620) of an input from the cyclist for a desired transmission ratio between the pedal axle (106) and the output pinion (108), and • adjustment (660) of the actuating ratio between the detected speed of the pedal axle (106) and the actuating motor speed of the actuating electric motor (210) based on the detected input from the cyclist.
4. Method according to any of the preceding claims, wherein the following step is carried out • adjustment (660) of the actuating ratio between the detected speed of the pedal axle (106) and the actuating motor speed of the actuating electric motor (210) based on the detected speed of the pedal axle (106), wherein the actuating ratio is adjusted in particular i. when the detected speed falls below a lower speed threshold value, and / or ii. when the detected speed exceeds an upper speed threshold value.
5. Method according to any of the preceding claims, wherein the following step is carried out • detection (632) of a torque applied by the cyclist to the pedal axle (106), and • adjustment (660) of the actuating ratio between the detected speed of the pedal axle (106) and the actuating motor speed of the actuating electric motor (210) based on the detected torque applied by the cyclist, wherein the actuating ratio is adjusted in particular i. when the detected torque applied by the cyclist falls below a lower cyclist torque threshold value, and / or ii. when the detected torque applied by the cyclist exceeds an upper cyclist torque threshold value.
6. Method according to any of the preceding claims, wherein the following step is carried out • detection (630) of a velocity of the bicycle (100), and / or • detection (631) of a slope of a route, and • adjustment (660) of the actuating ratio based on the detected bicycle velocity and / or the detected gradient of the route.
7. Method according to any one of the preceding claims, wherein, when a standstill of the bicycle (100) is detected based on a detected velocity of the bicycle (100), the actuating ratio is set to a predetermined starting setpoint value.
8. Method according to any one of the preceding claims, wherein the actuating ratio is selected from a predetermined list containing discrete values, wherein said discrete values each represent different predetermined transmission ratios to one another.
9. Method according to any one of the preceding claims, wherein the actuating ratio is adapted in such a way that the speed of the pedal axle (106) is continuously controlled to a setpoint revolution value or a setpoint revolution value range.
10. Method according to any of the preceding claims, wherein the following steps are carried out • detection (640) of at least one current pedal crank position, and • adjustment (660) of the actuating ratio additionally based on the detected current pedal crank position.
11. Method according to any of the preceding claims, wherein the following steps are additionally carried out • detection (632) of a torque applied by the cyclist to the pedal axle (106), and • generation (670) of a further motor torque based on the detected torque applied by the cyclist to the pedal axle (106) by means of a drive electric motor (240) for force assistance for the cyclist, wherein, in particular by means of a further speed reduction gear (530), the drive electric motor (240) i. is engagingly connected to the output component (221) of the planetary gear (220), or ii. is engagingly connected to the second input component (223) of the planetary gear (220), or iii. is arranged on a front or rear wheel hub of the bicycle (100).
12. Method according to any of the preceding claims, wherein the following steps are additionally carried out • detection (680) of an input from the cyclist for generator operation, and / or • detection (681) of a distance between the bicycle (100) and objects in the surroundings of the bicycle (100), and / or • detection (631) of a gradient of the route, and • detection (630) of a velocity of the bicycle (100), and • setting (682) of the actuating electric motor (210) and / or the drive electric motor in a generator operating mode based on the detected input of the cyclist for the generator operation and / or the detected distance between the bicycle (100) and objects in the surroundings of the bicycle (100) and / or the detected gradient of the route and based on the detected velocity of the bicycle (100), wherein the pedal axle (106) is fixed in particular to a housing (201) of the drive device (200).
13. Drive device (200) for a bicycle (100), wherein the drive device (200) comprises a planetary gear (220), an actuating electric motor (210) and a speed reduction gear (260), wherein the actuating electric motor (210) is connected for conjoint rotation or engagingly by means of the speed reduction gear (260) to a first input component (224) of the planetary gear (220) and a pedal axle (106) is connected for conjoint rotation or engagingly to a second input component (223) of the planetary gear (220) by means of the speed reduction gear, and an output component (221) of the planetary gear (220) different from the input components (223, 224) is connected, for conjoint rotation, to an output opinion (108) of the drive device (200), wherein a controller (250) of the drive device (200) is configured to carry out a method according to one of Claims 1 to 12 such that the controller (250) is configured • to detect a speed of the pedal axle (106) by means of a speed sensor, and • to actuate the actuating electric motor (210) based on the detected speed of the pedal axle (106) to generate an actuating motor speed for setting a transmission ratio between the pedal axle (106) and the output opinion (108), wherein the actuating motor speed is adjusted within a time period of twenty milliseconds after a change in the detected speed of the pedal axle, wherein • the planetary gear (220) is arranged coaxially around the pedal axle (106), • the pedal axle (106) is connected for conjoint rotation to the planetary carrier (223) of the planetary gear (220), • the actuating electric motor (210) is connected engagingly to the hollow shaft (224) of the planetary gear (220) by means of the speed reduction gear (260), wherein the hollow shaft (224) additionally has an external toothing, and • the sun gear (221) of the planetary gear (220) is arranged for conjoint rotation on a hollow output shaft (270) running coaxially around the pedal axle (106) and said hollow output shaft (270) is connected for conjoint rotation to the output pinion (108) of the drive device (200).
14. Drive device (200) according to Claim 13, wherein the controller (250) is configured to maintain a constant actuating ratio between the detected speed of the pedal axle (106) and the actuating motor speed at least over a quarter rotation of the pedal axis (106).
15. Drive device (200) according to either of Claims 13 and 14, wherein the speed sensor (285) comprises a mechanical, optical, inductive and / or electric incremental encoder or a continuously operating measuring system, wherein the speed sensor (285) is configured to identify a change in speed within 20 milliseconds.
16. Drive device (200) according to Claim 15, wherein the speed sensor (285) is connected to the pedal axle (106) by means of a high-driver gear stage (280).
17. Drive device (200) according to any one of Claims 13 to 16, wherein the controller (250) is configured • to detect an input from the cyclist for a desired transmission ratio between the pedal axle (106) and the output pinion (108) by means of a gear selector (230), wherein the gear selector (230) is arranged in particular on the handlebar (110) of the bicycle (100), and • to adjust the actuating ratio between the detected speed of the pedal axle (106) and the actuating motor speed based on the detected input from the cyclist.
18. Drive device (200) according to any one of Claims 13 to 17, wherein the controller (250) is configured • to adjust the actuating ratio between the detected speed of the pedal axis (106) and the actuating motor speed based on the detected speed and / or a detected torque applied by the cyclist to the pedal axis (106), which torque is measured by means of a torque sensor (520), wherein the actuating ratio is adjusted in particular i. when the detected speed falls below a lower speed threshold value, and / or ii. when the detected torque applied by the cyclist falls below a lower cyclist torque threshold value, and / or iii. when the detected speed exceeds an upper speed threshold value, and / or iv. when the detected torque applied by the cyclist exceeds an upper cyclist torque threshold value.
19. Drive device (200) according to any one of Claims 13 to 18, wherein the controller (250) is configured • to detect a velocity of the bicycle (100), in particular by means of a velocity sensor, for example a reed sensor on the front or rear wheel and / or by means of a position sensor for a global navigation satellite system, and / or • to detect a gradient of a route, in particular by means of an inertial measuring unit, and • to adjust the actuating ratio between the detected speed of the pedal axle and the actuating motor speed based on the detected bicycle velocity and / or the detected slop of the route.
20. Drive device (200) according to any one of Claims 13 to 19, wherein the controller (250) is configured • to detect at least one current pedal crank position, in particular by means of a pedal crank position sensor, a mechanical, optical, inductive and / or electric incremental encoder or a continuously operating measuring system for detecting a change in angle of the pedal axis, and • to adjust the actuating ratio based on the detected current pedal crank position.
21. Drive device (200) according to any one of Claims 13 to 20, wherein • the drive device (200) has a further drive electric motor (240), wherein the drive electric motor (240) i. is connected to the output component (221) of the planetary gear, or ii. is connected to the second input component (223) of the planetary gear, or iii. is arranged on a front or rear wheel hub of the bicycle (100), wherein • the drive device (200), in particular the controller (250), is configured to detect a torque applied by the cyclist to the pedal axle by means of a torque sensor (520), and • the drive electric motor (240), in particular by means of the controller (250), is configured to be actuated based on the torque applied by the cyclist.
22. Drive device (200) according to Claim 21, wherein the rotor position sensors of the drive electric motor (240) are used as speed sensor (280) for detecting the speed of the pedal axis (106).
23. Drive device (200) according to either of Claims 21 and 22, wherein • the drive device (200) is configured to detect a velocity of the bicycle by means of a velocity sensor, and • the drive electric motor (240) is configured to be additionally actuated based on the detected bicycle velocity.
24. Drive device (200) according to any one of Claims 14 to 23, wherein the controller (250) is configured • to detect an input from the cyclist for generator operation, and / or • to detect a gradient of the route, in particular by means of an inertial measuring unit, and • to detect a velocity of the bicycle by means of a velocity sensor, and • to switch the actuating electric motor (210) and / or the drive electric motor (240) to a generator operating mode based on the detected input from the cyclist for generator operation and / or the detected gradient of the route and based on the detected velocity of the bicycle (100), wherein the pedal axis (106) in particular is additionally fixed.
25. Drive device (200) according to any one of Claims 14 to 24, wherein the controller (250) is configured • to detect an input from the cyclist for desired manual operation without electrical assistance, and / or • to detect a current state of charge of a battery module (300) of the bicycle (100), and • to fix the first input component (224) of the planetary gear (220), in particular by means of a brake disc (226), which is connected for conjoint rotation to the input component (224), based on the detected input from the cyclist for desired manual operation and / or based on the detected current state of charge of the battery module (300), in particular by means of a brake (225).
26. Bicycle (100) having a drive device (200) according to any one of Claims 13 to 25.