Method for bringing about a change in a torque transmission state of a freewheel

Abstract

The invention relates to a method for bringing about a change in the torque transmission state of a freewheel (11) of a drive unit (2) for a muscle-powered vehicle. The drive unit (2) has an output element (6) for transmitting torque to a drive wheel of the muscle-powered vehicle. It also has a crank mechanism (4) for driving the output element (6) with the muscle power of the rider. Additionally, it has an electric motor (7) for providing at least temporary electrical assistance to the drive of the output element (6) via the freewheel (11). The method comprises determining (III) a target speed of the electric motor (7) and determining (IV) an actual speed of the electric motor (7). Furthermore, it comprises comparing (V) the determined actual speed with the determined target speed of the electric motor (7).Furthermore, it includes the output (VII) of a torque quantity to the electric machine (7). The output (VII) is based on the comparison (V) and is carried out to bring about the change in the torque transmission state of the freewheel (11).

Description

[0001] The present invention relates to a method for inducing a change in the torque transmission state of a freewheel for a human-powered vehicle. The vehicle can be a bicycle, for example, a pedelec. Furthermore, the present invention relates to a control device configured to carry out such a method, as well as to a drive device having such a control device.

[0002] Drive systems for bicycles with electric assistance, such as pedelecs, often feature a freewheel. The freewheel can connect an electric motor of the drive system to an output of the drive system. If the electric motor is to generate assistive torque, it must be synchronized with the speed of a crankshaft of the drive system, adjusted for gear ratio. This synchronization is called engaging the freewheel. The reverse process is called disengaging the freewheel. This can cause an unpleasant jolt and annoying noise for the rider.

[0003] DE 10 2021 201 405 A1 discloses a method for controlling an electric drive motor of an electrically driven bicycle, which causes the activation of drive assistance provided by the electric drive motor, and a method for controlling an electric drive motor of an electrically driven bicycle, which causes the deactivation of drive assistance provided by the electric drive motor. The electric drive motor is coupled to the drive train of the bicycle by means of a freewheel such that a torque generated by the drive motor leads to drive assistance in the forward direction of travel of the bicycle via the freewheel.

[0004] WO 2012 / 105198 A1 discloses an electric bicycle configured so that no shock occurs when starting in inertial running mode and when a wheel is driven by the motor. The pedaling force exerted on the pedals is detected by a sensor.

[0005] When the speed of an output rotating unit rotated by the rotor of a motor increases to the same speed as the speed of the front wheel, a clutch is engaged and transmits the assisting drive force from the output rotating unit to the front wheel. When the sensor detects a pedaling force greater than or equal to a predetermined magnitude and when the speed of the output rotating unit is greater than or equal to the speed of the front wheel, a control unit rotates the output rotating unit with an acceleration greater than or equal to the predetermined first acceleration. When the speed of the output rotating unit corresponds to an inertial running condition where the speed of the output rotating unit is lower than the speed of the front wheel, the control unit rotates the output rotating unit with a second acceleration lower than the first acceleration, at least when the clutch is engaged.This ensures that the assisting drive force is transferred smoothly from the output rotating unit to the front wheel.

[0006] The object of the present invention is to provide the quickest and most convenient way to apply a freewheel. This object is achieved by the subject matter having the features of the independent patent claims. Advantageous further developments are set out in the subclaims.

[0007] The present invention relates to a method for bringing about a change in the torque transmission state of a freewheel of a drive device for a human-powered vehicle. The freewheel can be a device having an input and an output. If torque is applied to the input in a torque transmission direction, the freewheel can transmit the torque to the output, provided the speed of the input is not lower than the speed of the output. If, however, the input rotates opposite to the torque transmission direction, the freewheel cannot fundamentally transmit any torque to the output. The torque transmission state of the freewheel describes the state of the freewheel in terms of whether or not it can transmit torque from the input to the output.If the torque transmission state of the freewheel is changed, a state for inducing torque transmission can be initiated or dissolved. The drive device can be a device for driving the human-powered vehicle and has an output element, for example a chainring, for transmitting torque from the drive device to a drive wheel of the vehicle. The drive wheel can be a rear wheel of a bicycle. The output element can transmit torque to the drive wheel via an endless circulating element, such as a chain or belt, and thereby set the drive wheel in rotation. The human-powered vehicle can be a two-wheeled vehicle, for example a bicycle. The bicycle can be designed as a pedelec or e-bike.

[0008] The drive device has a crank device for driving the output element using the driver's muscle power. The crank device can have a right and a left crank, which can be connected to one another in a rotationally fixed manner via a shaft. A pedal can be arranged on each crank. The drive device can have a transmission via which the crank device can be mechanically connected to the output element. The transmission can be a continuously variable transmission, for example a continuously variable power-split transmission. Using the pedals, the driver can transmit torque to the drive wheel via the drive device and thus cause the vehicle to move. The drive device further has an electric machine for at least temporarily electrically assisting the drive of the output element via the freewheel. The electric machine can be an electric motor.The electric machine can also function as a generator, for example to recuperate energy. The electric machine can be a brushless DC motor. The electrical assistance can involve the provision of torque via the electric machine, whereby the torque can be combined, for example summed, with the torque of the crank device by the drive device. The electrical assistance for driving the output element is provided via the freewheel. The electric machine can therefore be connected to the output element via the freewheel. An output of the freewheel can therefore be in mechanical operative connection with the crank device, for example in a permanent mechanical operative connection. In addition to the freewheel, other components, for example a gear stage, can be provided in the torque transmission path between the electric machine and the output element.

[0009] The method comprises determining a target speed of the electric machine. The target speed is a targeted speed of a rotating part of the electric machine or of a component that has a clearly defined kinematic relationship with the electric machine. The target speed can be a target speed or a target speed gradient. The target speed can be determined based on a temporal progression of at least one of these variables. The progression can comprise an increasing or decreasing speed and, alternatively or additionally, a speed gradient progression. The progression of the target speed can be determined at the beginning of the method. It can also be determined or adjusted continuously during the method. The progression can essentially follow a sigmoid, quadratic, and / or exponential function.The target speed can be determined based on a measured value and alternatively or additionally based on a calculation.

[0010] The method comprises a step of determining an actual speed variable of the electric machine. The actual speed variable is an actually existing speed variable of a rotating part of the electric machine or a component that has a fixed, kinematic relationship with the electric machine. The actual speed variable can comprise an actual speed and, alternatively or additionally, an actual speed gradient of the electric machine. The actual speed variable can correspond to a speed variable that can be present at an input of the freewheel, wherein this can be translated from the electric machine to the freewheel via a gear or another device. The actual speed variable can be determined via a detection device, for example a speed sensor. The detection device can comprise a speed sensor, which can be arranged on the drive wheel and / or on the electric machine.The method comprises comparing the determined actual speed of the electric machine with the determined target speed of the electric machine. The comparison may comprise determining which value is greater or whether the values ​​are equal. The comparison may comprise subtracting one value from the other value. The comparison may comprise determining an output value of a function, wherein the function may have the target and actual values ​​as input values.

[0011] The method comprises outputting a torque variable to the electric machine based on the comparison to bring about the change in the torque transmission state of the freewheel. The output can be via cable or wirelessly. The torque variable can be a torque. The torque variable can also be a variable that is suitable for influencing a torque, for example a rotational position or a speed of the electric machine. Outputting the torque can also comprise outputting a current intensity that correlates with the torque. Outputting can comprise a pulse width modulation (PWM) method. Outputting can comprise transmitting a signal to a control device of the electric machine, which can control the electric machine based on the received torque variable to adjust the variable based on a controlled variable, for example the current intensity.The change in the torque transmission state of the freewheel can comprise engaging or disengaging the freewheel according to the definition given at the beginning. Engagement of the freewheel can occur when no torque is being transmitted via the freewheel and the electric machine is rotating slower than an output of the freewheel. Engagement can comprise accelerating the electric machine so that the speed of the electric machine is synchronized with the speed of the freewheel output in order to transmit torque via the freewheel. Disengaging the freewheel can be carried out when the freewheel is engaged and comprises decelerating the electric machine so that the speed of the electric machine becomes slower than the speed of the freewheel output. Thus, after disengagement, no torque is transmitted via the freewheel.

[0012] The present method enables the vehicle's freewheel to be engaged or disengaged in a simple manner. The method can provide a smooth, comfortable, and jerk-free transition when engaging and disengaging the freewheel, resulting in a comfortable and safe driving experience for the driver. In one embodiment, the method can be provided only within a predetermined vehicle speed range, which can be between 0 and 25 km / h.

[0013] According to one embodiment, the method comprises detecting a rotational speed variable of the crank device. The detecting can comprise calculating and, alternatively or additionally, measuring. The rotational speed variable of the crank device can comprise a rotational speed, a rotational speed gradient, and, alternatively or additionally, another rotational speed variable of the crank device. The detecting can be carried out using a detecting device, for example, using a rotational speed sensor. Furthermore, in the present embodiment, the target rotational speed variable is determined based on the detected rotational speed variable of the crank device. The target rotational speed variable can be determined based on a temporal progression of the target rotational speed variable. When the freewheel is engaged, the progression can ultimately correspond to the crank rotational speed variable, adjusted for a gear ratio of a potentially present transmission.The target speed of the time profile can have a value of 0 at the end when the freewheel is released. By detecting the speed of the crank mechanism and determining the target speed of the electric machine based on this, synchronization of the electric machine with the crank mechanism is achieved in a particularly simple manner.

[0014] According to one embodiment, the target speed is determined based on a continuous target speed curve. This enables a continuous change in the torque transmission state of the freewheel. The speed curve is designed such that the engagement or disengagement of the freewheel occurs continuously and smoothly. The continuous target speed curve can be determined on a control device and alternatively or additionally stored there. Based on the continuous speed curve, the control device can determine a target speed at any time during the method. The continuous target speed curve can be a continuously differentiable curve that can, for example, run continuously from a target speed of 0 to a target speed, which, adjusted for gear ratio, can correspond to a speed of the crank device, or vice versa.

[0015] According to one embodiment of the method, the comparison comprises determining a deviation between the actual speed variable and the target speed variable. This can comprise subtracting one variable from the other. Furthermore, in this embodiment, the output of the torque variable comprises outputting it by means of a controller. A variable of the electric machine is fed back in order to close a control loop. The fed back variable can be the above-described actual speed variable of the electric machine, which can be designed and detected according to the above explanations. The control can be carried out by the control device. By controlling a torque variable of the electric machine, the goal of smooth and jerk-free engagement and disengagement of the freewheel with particularly high quality is achieved by reducing deviations from a desired target curve.The controller can be a PID, PI, PD, or other controller. In one embodiment, the controller is designed as a PID controller. In this embodiment, the setpoint speed and the actual speed can each be the setpoint and actual speeds.

[0016] According to one embodiment, the method comprises specifying at least one limit value for the torque value. The limit value is a maximum or minimum value which must not be exceeded or undershot by the method. If, for example, the method comes to the conclusion that a torque value above or below the limit value should be output, the value can be limited to the limit value or increased in this embodiment. The method can comprise specifying two limit values, wherein one limit value can be a minimum value and the further limit value a maximum value. In this way, a permissible torque range can be defined. The limit value can be a positive or a negative value. The limit value can be designed in accordance with the above explanations regarding the torque value.

[0017] Furthermore, the step of specifying can comprise reducing the amount of the at least one limit value as the method progresses. A profile of the limit value can be predetermined. The profile can be determined on the basis of a torque, a speed, or a speed gradient. The profile can also be specified using predetermined values. The profile can be determined in an initial step or changed continuously over the course of the method. A maximum and a minimum limit value can be reduced symmetrically as the method progresses. Both limit values ​​can have the same amount and differ only in their sign. If two limit values ​​are specified, both can be positive, both negative, or one positive and one negative.A reduction in magnitude can involve changing the value such that the magnitude of the value decreases as the process progresses, i.e., as time progresses. The limit or limits can be reduced until they reach a value of 0. By specifying and reducing the magnitude of one or more limit values, a smooth transition can be achieved when engaging or disengaging the freewheel. This also allows a smooth transition between a speed-based and a torque-based output, for example, control, of the drive torque.

[0018] According to one embodiment of the method, the step of outputting the torque value comprises setting a pilot torque based on a moment of inertia of the drive device. The pilot torque can be calculated based on the moment of inertia of the drive device, for example based on a calculation model. The pilot torque can be calculated based on a mass moment of inertia of the mass to be accelerated by the electric machine and its change in speed. The pilot torque can be recalculated when the method is carried out or stored in a control device. Several possible profiles of the pilot torque can be stored, and interpolation can take place between these profiles. The pilot torque can be provided in addition to a torque output by a controller.In this way, the pilot torque can be imposed on the torque quantity output to the electric machine. In addition, the torque quantity can have a further component, which can be determined based on the control method described above. In one embodiment, the output torque quantity has only the pilot torque and no further component.

[0019] By outputting the pilot torque, acceleration and deceleration of the electric motor is achieved particularly easily and effectively. This enables particularly convenient engagement and disengagement of the freewheel. The limit value described above can affect the pilot torque.

[0020] According to one embodiment of the method, this comprises receiving a change signal to bring about the change in the torque transmission state of the freewheel. The change signal can be generated by the rider or by the control device. The change signal can be generated by the rider by switching electrical assistance on or off. The change signal can be generated by the control device when the speed of the bicycle falls above or below a limit value and, alternatively or additionally, a change in a riding state is determined. The change signal can be sent whenever the freewheel is to be engaged or disengaged. A change in a riding state can be a change in a surface, an energy storage state, or another change.The control device can generate a change signal if an energy storage device has an energy level below a threshold value. In the present embodiment, the torque value is output upon receipt of the change signal based on the comparison step described above. For example, within the scope of the present embodiment, a control system, such as the speed control described above, can be activated upon receipt of the change signal. Within the scope of this embodiment, the torque value can be output based on torque control if the change signal is not received. Thus, the change signal can be used to switch between speed control and torque control.

[0021] The present invention further relates to a control device for a drive device of a human-powered vehicle. The control device is configured, i.e. specifically prepared, for example programmed, to carry out the method according to one of the embodiments described above. The control device can be provided as part of the drive device or separately from it. The control device can have one or more interfaces. Thus, the control device can communicate with the various components of the drive device to carry out the method, for example via a CAN bus. The control device can have one or more components that can be provided at the same or different locations. The present invention further relates to a drive device for a human-powered vehicle with such a control device.The human-powered vehicle may have an energy storage device, such as a battery, to supply the electric motor with energy. The human-powered vehicle may be configured as a bicycle and include brakes, a saddle, handlebars, a frame, a front and rear wheel, a chain, and other known bicycle components. For an understanding and the advantages of the individual features, reference is made to the above explanations in connection with the method of the present invention. Fig. 1 shows a schematic view of a bicycle designed as a pedelec according to an embodiment of the present invention. Fig. 2 shows schematically a drive device of the Fig. 1 according to an embodiment of the present invention. Fig. 3 shows a flowchart of a method for bringing about a change in a torque transmission state of a freewheel of the drive device from Fig. 2 according to an embodiment of the present invention. Fig. 4 shows schematically a speed curve of an electric machine of the drive device from Fig. 2 when carrying out the Fig. 3 described procedure.

[0022] Fig. 1 shows a schematic representation of a bicycle 1 according to an embodiment of the present invention. Fig. The bicycle 1 shown in Figure 1 has a frame (not further explained) on which a front wheel 10 is mounted as a non-driven wheel and a rear wheel 3 as a drive wheel. The bicycle 1 also has elements (not further explained) that are typical of a bicycle.

[0023] These include, for example, a saddle, a handlebar, a brake system and other attachments, which are not taken into account in the following explanation. Fig. The bicycle 1 shown in Figure 1 is designed as a pedelec and has a drive device 2 mounted in the area of ​​the bottom bracket position of the frame of the bicycle 1. To operate the drive device 2, an energy storage device 9 is provided on the frame of the bicycle 1, in the illustration on the down tube of the frame. This energy storage device is designed as a rechargeable battery. Furthermore, the Fig. 1 has a control device 8 which is also mounted on the frame of the bicycle 1.

[0024] The rear wheel 3, designed as a drive wheel, is coupled to the drive device 2 via a chain (not shown). The drive device 2 has a crank device 4, via which a rider of the bicycle 1 can introduce muscle power into the drive device 2. The drive device 2 further has a Fig. 2, in the form of a chainring, which is mechanically coupled via the chain to a pinion (not shown) of the rear wheel 3. Rotation of the output element 6 is transmitted via the chain to the rear wheel 3, so that the rear wheel 3 can be driven.

[0025] Fig. 2 shows the drive device 2 from Fig. 1 according to an embodiment of the present invention in a schematic view. The drive device 2 corresponds in structure to that shown in Fig. 1 on the bicycle 1 mounted drive device 2. The drive device 2 has an electric machine 7, which is connected to the in the in Fig. 1 shown energy storage device 9. The operation of the electric machine 7 by the electrical energy stored in the energy storage device 9 is determined by the Fig. 1. The control device 8, the energy storage device 9, and the electric machine 7 are thus electrically and, in this case, signal-wise coupled to one another.

[0026] The electric machine 7 serves to transmit a drive torque to the output element 6 of the drive device 2. More precisely, a rotation of an output shaft of the electric machine 7 can be transmitted to the output element 6 via a freewheel 11 with a defined transmission ratio. The electric machine 7 serves in the present embodiment to electrically assist the muscle power introduced into the drive device 2 by the crank device 4. The muscle power introduced into the drive device 2 via the crank device 4 is transmitted to the output element 6 via a transmission device 5. Thus, the drive force of the electric machine 7 and the muscle power introduced via the crank device 4 are combined, in this case summed, by the drive device 2. The thus combined drive force is applied to the Fig. 1 shown rear wheel 3 to drive the same.

[0027] The electric machine 7 is connected to the output element 6 via the freewheel 11. In this case, an input (not shown) of the freewheel 11 is permanently coupled in a rotationally fixed manner to the electric machine 7, and an output (not shown) of the freewheel 11 is permanently coupled to the output element 6. If the electric machine 7 rotates in a first direction, its speed can be equal to or lower than a speed of the output of the freewheel 11. If the speed of the electric machine 7 corresponds to the speed of the output of the freewheel 11, the electric machine 7 is mechanically coupled to the output element 6 via the freewheel 11 in order to transmit torque to the output element 6. If the speed of the electric machine 7 in this direction of rotation is lower than the speed of the output of the freewheel 11, the freewheel rotates freely, so that no torque is transmitted from the electric machine 7 to the output element 6.However, if the electric machine 7 rotates in a direction opposite to the first direction, the freewheel 11 does not transmit any torque to the output element 6, regardless of the speed of the electric machine 7.

[0028] The Fig. The electric machine 7 shown in Figure 2 has a signal output from which the rotational speed of an output shaft of the electric machine 7 can be derived. This signal output is coupled to a signal input of the control device 8. With this signal, the control device 8 is provided with information regarding the current rotational speed of the electric machine 7 at any time. Furthermore, in the present embodiment, the drive device 2 has a rotational speed sensor which detects the rotational speed of the crank device 4 and provides the crank rotational speed to the control device 8. The control device 8 is configured to Fig. 3 described procedures. The steps are explained in relation to the application of the freewheel 11. In Fig. 4 shows how the curves of a target speed and an actual speed of the electric machine 7 are changed over time by the method. A speed is shown along the vertical axis and time is shown along the horizontal axis. The dashed line corresponds to a target speed 20. The target speed 20 is the speed that the electric machine should have at the end of the method. The target speed and the actual speed initially correspond to 0 and the target speed 20 is a positive number. In such an initial state, the freewheel 11 does not transmit any torque. Thus, the electric machine 7 initially provides no assistance. After the method has ended, the freewheel 11 is engaged. During the method, the target speed curve 21 increases continuously until the target speed 20 is reached. The actual speed 22 of the electric machine 7 follows the target speed 21 with a time delay.

[0029] At the beginning of the Fig. 3, a step of receiving I a change signal by the control device 8 for bringing about the change in the torque transmission state of the freewheel 11 is provided. In the Fig. In the case illustrated in Figure 4, a signal for the engagement of the freewheel 11 is received because the driver switches on the assistance of the electric machine 7 while driving or the control device 8 outputs a signal for assistance by the electric machine 7. Receiving I is followed by detecting II a rotational speed variable of the crank device 4, wherein the rotational speed variable in this case is a rotational speed of the crank device 4. The rotational speed of the crank device 4 is detected in the present embodiment via the rotational speed sensor described above. Based on the detected crank speed, the control device 8 determines a target rotational speed variable of the electric machine 7 in a subsequent step III. In the present embodiment, the target rotational speed variable is determined based on the target rotational speed curve 21 stored in the control device 8, which in Fig. 4. The target speed curve 21 describes, as a function of time, a target speed of the electric machine 7, which is 0 at the beginning of the method and continuously increases to the target speed 20.

[0030] Subsequently, in a step of determination IV, an actual speed variable, in this case the speed, of the electric machine 7 is determined. At the beginning of the method, this actual speed is, as in Fig. 4, also 0, increases over time until the target speed 20 is reached. The target and actual speeds of the electric machine 7 are now compared with one another in a step V, wherein the comparison V comprises the determination V.1 of a deviation between the two variables. In this case, the actual speed is subtracted from the target speed. In a specification step VI, a minimum and a maximum torque are specified. These limit values ​​are reduced in magnitude over the time of the method in a step VI.1, in this case reduced in a ramp-like manner, thus providing a smaller range of permissible torques. The ramp-like profiles can be stored on the control device 8. The profiles for the limit values ​​are designed such that they reduce in a ramp-like manner from the start of the method to 0 when the target speed 20 is reached.

[0031] The last step of the flowchart of the Fig. The method illustrated in Figure 3 involves outputting VII of the drive torque to the electric machine 7. This includes determining VII.1 a pilot torque based on a moment of inertia of the components of the drive device 2 to be accelerated by the electric machine 7. In the present case, this moment of inertia of the drive device 2 is multiplied by the speed change of the electric machine 7 to determine the pilot torque. This pilot torque represents a first component of the drive torque output to the electric machine 7.

[0032] In a further aspect of outputting VII of the drive torque, a further component in the drive torque is determined by the control device 8 on the basis of the deviation between the target and actual speed of the electric machine 7 determined in step V.1. The further component is determined in this case by means of a PID controller, which is part of the control device 8. By feeding back the actual speed in the determination step IV, a control loop is closed, thus enabling speed-based control. If the value determined by the PID controller is greater or smaller than the limit values ​​specified in step VI, the value is limited to the respective limit value. The drive torque output by the PID controller is summed with the described pilot control torque. The method then returns to step I. By means of the described method, the Fig. 4 is achieved. As soon as the speeds of the crank device 4 and the electric machine 7 are synchronized, the method ends and no further signal is output in step I to engage the freewheel 11. In this state, the control device 8 switches to torque-based control of the electric machine 7. In the event of the freewheel 11 being released, operation takes place in the opposite manner to the above statements, in which Fig. 4 is moved in the opposite direction from the target speed 20 to the speed 0. Reference symbol 1 bicycle 2 drive device 3 drive wheel 4 Crank device 5 Gear device 6 Output element 7 electric machine 8 Control device 9 Energy storage device 10 front wheel 11 Freewheel 20 Target speed 21 Target speed curve 22 Actual speed curve I Receive change signal II Detecting the speed of the crank mechanism III Determine target speed of electric machine IV Determine actual speed of electric machine V Compare actual speed with target speed V.1 Determine deviation VI Specify limit VI.1 Reduce limit VII Output torque size VII.1 Determining the pre-control moment

Claims

[1] Method for bringing about a change in a torque transmission state of a freewheel (11) of a drive device (2) for a muscle-powered vehicle, wherein the drive device (2) has an output element (6) for transmitting a torque to a drive wheel of the muscle-powered vehicle, a crank device (4) for driving the output element (6) with a muscle power of the driver and an electric machine (7) for at least temporarily electrically assisting the drive of the output element (6) via the freewheel (11), comprising determining (III) a target speed of the electric machine (7), determining (IV) an actual speed of the electric machine (7),comparing (V) the determined actual speed value with the determined target speed value of the electric machine (7) and outputting (VII) a torque value to the electric machine (7) based on the comparison (V) to bring about the change in the torque transmission state of the freewheel (11)., [2] Method according to claim 1, characterized by in that the method comprises detecting (II) a rotational speed variable of the crank device (4), and in that determining (III) the target rotational speed variable of the electric machine (7) comprises determining (III) the target rotational speed variable on the basis of the detected rotational speed variable of the crank device (4). [3] Method according to claim 1 or 2, characterized by that the determination (III) of the target speed variable is carried out based on a continuous target speed variable curve (21) in order to enable a continuous change in the torque transmission state of the freewheel (11). [4] Method according to one of the preceding claims, characterized by in that the comparison (V) comprises a determination (V.1) of a deviation between the actual speed value and the target speed value, and in that the output (VII) of a torque value is carried out by means of a controller. [5] Method according to one of the preceding claims, characterized by that the method comprises specifying (VI) at least one limit value for the torque value. [6] Method according to claim 5, characterized by that the specification (VI) comprises a reduction (VI.1) of the amount of at least one limit value as the method progresses. [7] Method according to one of the preceding claims, characterized by that the outputting (VII) of the torque quantity comprises setting (VII.1) a pilot control torque based on a moment of inertia of the drive device (2). [8] Method according to one of the preceding claims, characterized byin that the method comprises receiving (I) a change signal for bringing about the change in the torque transmission state of the freewheel (11), and in that the output (VII) of the torque variable takes place upon receipt (I) of the change signal based on the comparison (V). [9] Control device (8) for a drive device (2) of a muscle-powered vehicle, which is designed to carry out a method according to one of the preceding claims. [10] Drive device (2) for a muscle-powered vehicle with a control device (8) according to claim 9.

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