Method for operating a pedal-powered vehicle and pedal-powered vehicle

Abstract

The present invention relates to a method (100) for operating a pedal-driven vehicle (200), comprising at least one drive (201) for providing a drive torque for propelling the pedal-driven vehicle (200), a gearshift (202) for providing a variable transmission ratio, and a control unit (203), the method (100) comprising: - Providing (110) an initial drive torque by the drive (201), - Providing (110) switching information for a planned switching operation, the switching information comprising a switching direction indication, in particular by means of the gearshift (202), - Determining (120) a second drive torque depending on the switching information, in particular by the control unit (203), wherein the second drive torque is less than or equal to the first drive torque, and - Controlling (130) the drive (201) such that the drive torque provided by the drive (201) corresponds to the second drive torque, in particular by the control unit.

Description

State of the art

[0001] Pedal-powered vehicles, especially electric bicycles, may be equipped with an additional electric drive designed to assist the rider while pedaling and thus simplify the propulsion of the vehicle for the rider.

[0002] When gear changes are performed in the pedal-driven vehicle to change a gear ratio in a drivetrain of the pedal-driven vehicle, a drive torque provided by the electric drive can have negative effects on components of the gearshift used for gear changes.

[0003] For example, with derailleur gears, it's necessary to shift the chain to a different sprocket when changing gears. During this shift, the chain can be accelerated sharply by the electric drive due to a temporary loss of contact with the sprocket and the resulting lack of load on the drivetrain. When contact between the sprocket and chain is subsequently re-established, this leads to a sudden braking action of the chain. Such a shifting process can damage the components involved and, moreover, reduces the user comfort of the pedal-powered vehicle, as the rider perceives such a shift as jerky. Disclosure of the invention

[0004] The present invention relates to a method for operating a pedal-driven vehicle, a pedal-driven vehicle, a computer program product, a computer-readable medium, and a data carrier signal. Further features and details of the invention will become apparent from the dependent claims, the description, and the drawings. Features and details described in connection with the method according to the invention naturally also apply in connection with the pedal-driven vehicle according to the invention and / or in connection with the computer program product according to the invention and / or in connection with the computer-readable medium according to the invention and / or in connection with the data carrier signal according to the invention, and vice versa, so that the disclosure of the individual aspects of the invention always includes, or allows for, reciprocal reference.

[0005] The invention presented here serves in particular to provide an improved operation of a gearshift of a pedal-driven vehicle with regard to improved user comfort of the pedal-driven vehicle and / or an increased service life of the components involved.

[0006] According to a first aspect, the present invention relates to a method for operating a pedal-driven vehicle, comprising at least one drive for providing a drive torque for propelling the pedal-driven vehicle, a gearshift for providing a variable transmission ratio, and a control unit, the method comprising: - Providing an initial drive torque through the drive, - Providing switching information for a planned switching operation, the switching information including a switching direction indication, in particular through the gearshift, - Determining a second drive torque depending on the switching information, in particular by the control unit, wherein the second drive torque is less than or equal to the first drive torque and - Controlling the drive in such a way that the drive torque provided by the drive corresponds to the second drive torque, in particular by the control unit.

[0007] It is preferably intended that the aforementioned process steps are executed in the specified order. Additionally or alternatively, it is conceivable that at least individual process steps are executed repeatedly, particularly in a loop and / or, at least partially, simultaneously. Additionally or alternatively, the process can be implemented as a computer-implemented method.

[0008] In other words, a method for operating a pedal-driven vehicle is proposed. The pedal-driven vehicle comprises a drive for providing drive torque to propel the vehicle. The drive can preferably be an electric motor and / or be positioned in a central motor arrangement on the pedal-driven vehicle.

[0009] Furthermore, the pedal-driven vehicle comprises a gearshift for providing a variable gear ratio, particularly in a drivetrain of the pedal-driven vehicle, as well as a control unit. With regard to the present invention, the gearshift can particularly preferably be designed as a derailleur gearshift. A different design of the gearshift, e.g., as a hub gear, is also conceivable.

[0010] According to the invention, a first drive torque is provided by the drive, in particular to assist a driver of the pedal-driven vehicle. Furthermore, it is provided that, in particular by the gearshift, shift information for a planned shifting operation is provided, especially to the control unit.

[0011] The shifting information includes at least a shifting direction indication, whereby the shifting direction indication is characteristic of whether the shifting process involves moving to a higher gear, i.e., a higher gear ratio, or to a lower gear, i.e., a lower gear ratio.

[0012] If the transmission is manual, the shift direction can be generated, for example, depending on the action of a specific shift lever. In manual transmissions, it is common for one shift lever to be used for upshifting and another for downshifting, or for a single shift lever to be movable in different directions for upshifting and downshifting. In this way, the shift direction can be clearly determined based on the action of a shift lever. With automatic or semi-automatic transmissions, the shift information can be provided directly by the transmission itself, as information regarding the shift direction, target gear, and other parameters for a future shift is available in advance.

[0013] Furthermore, it is provided that, particularly by the control unit, a second drive torque is generated depending on the switching information, especially at least the switching direction. According to the invention, the second drive torque is less than or equal to the first drive torque. It is further provided that the drive, particularly by the control unit, is controlled in such a way that the second drive torque is provided by the drive.

[0014] A method according to the invention offers the advantage that the drive torque provided by the drive is reduced or maintained depending on the shift direction intended for a planned shifting operation. This prevents mechanical damage to the gearshift during the shifting process and simultaneously maintains the drive torque for the longest possible time and as evenly as possible to support the driver, provided that no damage to the gearshift is to be expected.

[0015] Preferably, in relation to the present invention, the second drive torque can be smaller or selected to be lower when the shift direction indicates an increase in the gear ratio than when the shift direction indicates a reduction in the gear ratio. In other words, the second drive torque can be reduced more significantly compared to the first drive torque when the shift direction indicates an upshift to a higher gear, i.e., towards a higher gear ratio, than when a downshift to a lower gear, i.e., towards a lower gear ratio, occurs.

[0016] Within the scope of the invention, it was recognized that upshifting in derailleur gears results in a brief freewheeling of the chain, as the chain is shifted from a larger sprocket on the cassette to a smaller one. This can lead to strong acceleration of the chain by the drive during the freewheeling phase and a correspondingly jerky deceleration when the chain engages the smaller sprocket. In contrast, downshifting in derailleur gears typically utilizes shift aids, which allow for a potentially temporarily reduced, but still continuous, power transmission. Therefore, advantageously, a higher drive torque can be maintained during downshifting, i.e., a reduction in the gear ratio, without risking damage to the gear system or impairing rider comfort.

[0017] In particular, it may be stipulated that the second drive torque corresponds to the first drive torque if the switching direction is characteristic of a reduction in the transmission ratio. Alternatively, however, it may also be stipulated that the second drive torque is always less than the first drive torque.

[0018] It may be provided with regard to the present invention that the method further comprises: - Determining a time for controlling the drive depending on the switching information, in particular at least the switching direction specification, whereby in particular the control of the drive takes place at the determined time.

[0019] In other words, it can be provided that, in particular by the control unit, a time at which the drive is controlled in such a way that the second drive torque is provided is determined depending on the switching information, in particular at least the switching direction specification, and in particular that the drive is controlled at the determined time.

[0020] Within the scope of the invention, it was recognized that in derailleur gear systems, the actual movement of the chain can be delayed relative to the triggering of the shifting process via a shift lever or relative to the movement of a front derailleur. The extent of this time delay depends on the shifting direction. For example, when shifting up, the chain generally moves faster due to the change to a smaller sprocket than when shifting down, where the chain, especially when using shift ramps, has to be moved to a larger sprocket. However, the drivetrain only needs to be relieved of stress when the chain is actually moving, and not simply when the front derailleur moves.

[0021] It is preferable to have the timing for activating the drive selected later if the switching direction is characteristic of a reduction in the transmission ratio, rather than if it is characteristic of an increase in the transmission ratio. This allows the drive torque provided by the drive to be maintained unchanged for as long as possible, depending on the switching direction.

[0022] The timing for engaging the drive can be determined, for example, based on the minimum number of revolutions of the cassette or a sprocket required for the planned shifting operation before the chain starts to move. This minimum number of revolutions can be specified by the shift information or provided by the gearshift mechanism itself for the planned shifting operation.

[0023] Alternatively, a minimum required number of revolutions can be determined model-based, particularly by the control unit, depending on the switching information, especially a target setting and / or switching direction. Specifically, a functional relationship can be defined which, depending on the switching information as input, provides a minimum required number of revolutions as output.

[0024] Using the minimum number of revolutions required for the sprocket or cassette before the chain starts moving, and knowing the current rotational speed of the cassette or sprocket (which can be measured, for example, by a speed sensor), a time can be determined during which the chain is not yet moving and therefore no reduction in drive torque is necessary. After this time has elapsed, the drive torque can preferably be reduced to the second drive torque value.

[0025] In particular, it is conceivable that the second drive torque, at least if the switching direction specification is characteristic of an increase in the transmission ratio, is a maximum of 80%, preferably a maximum of 70%, particularly preferably a maximum of 60%, or a maximum of 50%, or a maximum of 40% of the first drive torque.

[0026] With regard to the present invention, it may further be provided that the method includes the following: - Detecting driver torque provided by a driver of the pedal-driven vehicle for propulsion of the pedal-driven vehicle, in particular by a detection unit, and - Determining the second drive torque such that the sum of the second drive torque and the driver torque is less than or equal to a total torque limit.

[0027] In other words, it may be provided that, when determining the second drive torque, a driver torque provided by the driver of the pedal-driven vehicle is also taken into account. The driver torque can, for example, be introduced or introduced via a crank mechanism of the pedal-driven vehicle, particularly into a drivetrain of the pedal-driven vehicle. It may be specifically provided that the second drive torque is determined in such a way that the sum of the second drive torque and the driver torque does not exceed a predetermined torque limit.

[0028] The torque limit can preferably be selected such that no mechanical damage to the gearshift or a reduction in user comfort for the driver is to be expected from a torque in the drivetrain corresponding to the torque limit during the planned shifting process. Taking the driver's torque into account can prevent damage to the gearshift even more effectively.

[0029] Within the scope of the invention, it can be provided that the second drive torque is defined as a torque that opposes the rider torque. In other words, it can be provided that the second drive torque is a drive torque that counteracts the rider torque or at least partially compensates for it. This allows the drivetrain, in particular a chain used for torque transmission, to be relieved of stress during the shifting process, and mechanical damage to the gearshift to be avoided even more effectively. In particular, high rider torques can thus be reduced to a level in the drivetrain that is acceptable during the shifting process.Such a procedure can be used particularly in drive variants without a drive freewheel, i.e. in drive variants where the drive torque provided by the drive acts directly on a crank mechanism, via which the driver torque is also introduced.

[0030] With regard to the present invention, it may further be advantageous if the switching information includes a target profile, wherein the target profile is characteristic of a target profile of the planned switching process, and wherein the method further comprises: - Determining the second drive torque and / or the time to activate the drive, additionally depending on the target gear specification.

[0031] A target gear setting should be understood as an indication of the gear into which the transmission is to be shifted. Considering the target gear setting offers the advantage that not only the shift direction is taken into account when determining the second drive torque, but also the target gear itself, and thus the range of available gears in which the transmission is currently shifting.

[0032] A target gear indicator can be provided easily and reliably, especially with automatic or semi-automatic transmissions, since the transmission always knows the current gear and the user interfaces are assigned unambiguous shifting operations. Even with manual transmissions, the target gear indicator can be determined from the current gear and the shift direction, which can be derived from the respective actuation of a specific user interface, particularly a gearshift lever.

[0033] Preferably, it can be provided that, with an increasing gear ratio of the target gear (characterized by the target gear specification), the second drive torque is selected to be lower, particularly increasingly so. In other words, it can be provided that the second drive torque is reduced more significantly compared to the first drive torque the higher the target gear (characterized by the target gear specification) is. This approach has proven advantageous within the scope of the present invention with regard to avoiding mechanical damage to the gearshift mechanism.

[0034] Additionally or alternatively, it can be provided that, with an increasing gear ratio of the target gear (characterized by the target gear specification), the point in time for engaging the drive is selected earlier, and in particular, increasingly earlier. In other words, it can be provided that the higher the target gear (characterized by the target gear specification), the earlier the point in time for engaging the drive is selected. This approach has proven advantageous within the scope of the present invention with regard to avoiding mechanical damage to the gearshift.

[0035] It may be advantageous to provide that the procedure also includes: - Controlling the drive in such a way that the drive torque provided by the drive corresponds again to the first drive torque, in particular by the control unit.

[0036] In other words, it can be provided that, after the second torque has been supplied, particularly after a predetermined period of time, the drive is activated to restore the first drive torque. This activation of the drive can occur, in particular, after a predetermined period of time or at a predetermined time, once the drive torque has been reduced to the second drive torque. This allows the original driver assistance provided by the drive to be restored.

[0037] In particular, the switching information may also include a start time and / or a planned duration for carrying out the planned switching operation. Preferably, in this context, it may be provided that the predetermined time period after which the drive is activated to provide the first drive torque again, or a predetermined time at which the drive is activated to provide the first drive torque again, is determined as a function of the start time and / or the planned duration for carrying out the planned switching operation.

[0038] The planned duration of a gear shift can be determined, in particular, depending on the shift direction and / or the target gear. For example, with derailleur gears, upshifting is relatively quick, as the chain is moved from a larger sprocket to a smaller one on the cassette. Downshifting, on the other hand, takes longer, as the shift only occurs when a shift ramp reaches the correct position on the cassette, which can take up to one full rotation. The presence and number of shift ramps can also vary, depending on the current gear and the target gear being shifted to.

[0039] In particular, a maximum number of revolutions of the cassette or a single sprocket required for a complete shift can be specified. Based on this, and knowing the current rotational speed of the cassette or sprocket (which can be detected, for example, by a speed sensor), a time can be determined after which the shift is reliably completed. This time can then be used as the planned duration of a shift, after which the drive torque can be increased again. Such a maximum required number of revolutions can, for example, be included in the shift information or provided by the gearshift mechanism for the planned shift.

[0040] Alternatively, a maximum required number of revolutions can be determined model-based, particularly by the control unit, depending on the switching information, especially a target setting and / or switching direction. Specifically, a functional relationship can be defined which, depending on the switching information as input, provides a maximum required number of revolutions as output.

[0041] It may also be provided that the method includes detecting the rotational speed of a sprocket cassette of the pedal-driven vehicle, in particular by a detection unit or a speed sensor.

[0042] According to a second aspect, the present invention relates to a pedal-driven vehicle comprising at least one drive for providing drive torque for propelling the pedal-driven vehicle, a gearshift for providing a variable gear ratio, and a control unit. The pedal-driven vehicle is preferably configured to be operated according to a method according to the invention, in particular according to a method according to any one of claims 1 to 7. Preferably, the pedal-driven vehicle can be configured as a bicycle, preferably an electric bicycle or pedelec. With respect to a pedal-driven vehicle, the same advantages arise as those described with respect to a method according to the invention. The pedal-driven vehicle can preferably comprise two wheels, in particular a front wheel and a rear wheel.

[0043] In particular, the transmission may be designed to provide a variable gear ratio, especially in the drivetrain of a pedal-driven vehicle. The gear ratio may be characteristic of the number of revolutions of a drive wheel of the pedal-driven vehicle per revolution of the vehicle's crank mechanism. A high gear ratio, or a high gear, thus characterizes a comparatively high number of revolutions of the drive wheel for each revolution of the crank mechanism. Conversely, a low gear ratio, or a low gear, characterizes a comparatively low number of revolutions of the drive wheel for each revolution of the crank mechanism. In particular, the driver of the pedal-driven vehicle can apply torque to propel the vehicle via the crank mechanism, specifically through pedals.

[0044] In particular, a rear wheel of the pedal-driven vehicle can serve as a drive wheel, which can be driven via a crank mechanism. A functional connection between the drive wheel and the crank mechanism can be established via the gearshift, whereby the gearshift allows for a variable gear ratio between the drive wheel and the crank mechanism.

[0045] The gear system can be designed as a derailleur system or a hub gear system. The present invention has proven particularly advantageous with regard to a derailleur system.

[0046] Additionally or alternatively, the transmission may be designed as an automatic or at least semi-automated transmission. In particular, it may be designed so that gear changes do not need to be manually initiated by the driver, but are automated based on one or more driving parameters. A driving parameter could be, for example, the speed of the pedal-driven vehicle, the pedaling cadence of the driver, the torque applied by the driver to propel the vehicle, or the power applied by the driver to propel the vehicle.

[0047] Within the scope of the invention, it may be provided that at least one detection unit comprises at least one torque sensor for detecting driver torque. The driver torque can, for example, be detected at a crank mechanism of the pedal-driven vehicle, via which the driver torque can be applied.

[0048] Within the scope of the invention, it may be provided that at least one detection unit comprises at least one speed sensor for detecting the speed of a sprocket cassette of the pedal-driven vehicle.

[0049] Within the scope of the invention, it may be provided that at least one gearshift and / or control unit and / or detection unit comprises means for data processing. The means for data processing may include at least one processor and / or working memory and / or non-volatile data storage.

[0050] At least one control unit can be brought into communication and / or signal connection with a gearbox and / or detection unit and / or at least one drive, at least temporarily. This allows data and / or control signals to be exchanged between the respective units or components.

[0051] According to a third aspect, the present invention relates to a computer program product comprising instructions that cause a pedal-driven vehicle according to the invention, in particular a pedal-driven vehicle according to claim 8, to execute a method according to the invention, in particular a method according to the first aspect of the invention. With respect to a computer program product according to the invention, the same advantages arise as those already described with respect to a method and / or a pedal-driven vehicle according to the invention.

[0052] According to a fourth aspect, the present invention relates to a computer-readable medium, in particular a storage medium, wherein a computer program product according to the invention, in particular a computer program product according to claim 9, is stored on the computer-readable medium. With respect to a computer-readable medium according to the invention, the same advantages arise as those already described with respect to a method and / or a pedal-driven vehicle and / or a computer program product according to the invention.

[0053] According to a fifth aspect, the present invention relates to a data carrier signal that transmits a computer program product according to the invention, in particular a computer program product according to claim 9. With regard to a data carrier signal according to the invention, the same advantages arise as those already described with regard to a method according to the invention and / or a pedal-driven vehicle according to the invention and / or a computer program product according to the invention and / or a computer-readable medium according to the invention.

[0054] Further advantages, features, and details of the invention will become apparent from the following description, in which exemplary embodiments of the invention are described in detail with reference to the drawings. The features mentioned in the claims and the description can each be essential to the invention individually or in any combination.

[0055] Each schematically illustrates: Fig. 1 a view of a procedure and Fig. 2 A view of a pedal-powered vehicle.

[0056] The Fig. Figure 1 shows a schematic view of a method 100 for operating a pedal-driven vehicle 200, comprising at least one drive 201 for providing a drive torque for propelling the pedal-driven vehicle 200, a gearshift 202 for providing a variable transmission ratio, and a control unit 203, the method 100 comprising: - Providing 110 of an initial drive torque through the drive 201, - Providing 110 switching information for a planned switching operation, the switching information comprising a switching direction indication, in particular by means of the gearshift 202, - Determine 120 a second drive torque depending on the switching information, in particular by the control unit 203, wherein the second drive torque is less than or equal to the first drive torque and - Controlling 130 of the drive 201 such that the drive torque provided by the drive 201 corresponds to the second drive torque, in particular by the control unit 203.

[0057] Furthermore, it shows Fig. 2 A schematic view of a pedal-driven vehicle 200, comprising at least one drive 201 for providing drive torque for propelling the pedal-driven vehicle 200, a gearshift 202 for providing a variable gear ratio, a control unit 203, and a detection unit 204. The detection unit 204 and the control unit 203 can (as shown here) optionally be integrated in a common unit. Preferably, the pedal-driven vehicle 200 is configured to operate according to a Fig. The procedure described in section 1 is to be operated in 100.

[0058] The preceding explanation of the embodiments describes the present invention solely by way of examples. Naturally, individual features of the embodiments can be freely combined with one another, provided this is technically feasible, without departing from the scope of the present invention.

Claims

[1] Method (100) for operating a pedal-driven vehicle (200), comprising at least a drive (201) for providing a drive torque for propelling the pedal-driven vehicle (200), a gearshift (202) for providing a variable transmission ratio and a control unit (203), the method (100) comprising: - Providing (110) an initial drive torque by the drive (201), - Providing (110) switching information for a planned switching operation, the switching information comprising a switching direction indication, in particular by means of the gearshift (202), - Determining (120) a second drive torque depending on the switching information, in particular by the control unit (203), wherein the second drive torque is less than or equal to the first drive torque and - Controlling (130) the drive (201) such that the drive torque provided by the drive (201) corresponds to the second drive torque, in particular by the control unit (203). [2] Method (100) according to claim 1, characterized by , that the second drive torque is smaller when the switching direction specification is characteristic of an increase in the transmission ratio than when the switching direction specification is characteristic of a reduction in the transmission ratio. [3] Method (100) according to any one of the preceding claims, characterized by , which further includes: - Determining a time for controlling (130) the drive (201) depending on the switching information and controlling (130), wherein the controlling (130) of the drive (201) takes place at the determined time. [4] Method (100) according to claim 3, characterized by, that the time for controlling (130) the drive is chosen later if the switching direction specification is characteristic of a reduction of the transmission ratio than if the switching direction specification is characteristic of an increase of the transmission ratio. [5] Method (100) according to any one of the preceding claims, characterized by , which further includes: - Detecting a driver torque provided by a driver of the pedal-driven vehicle (200) for the propulsion of the pedal-driven vehicle (200), in particular by a detection unit (204), and - Determining the second drive torque such that the sum of the second drive torque and the driver torque is less than or equal to a total torque limit. [6] Method (100) according to any one of the preceding claims, characterized by, that the second drive torque is determined as a torque which is opposite to the driver torque. [7] Method (100) according to any one of the preceding claims, characterized by , that the switching information includes a target profile specification, wherein the target profile specification is characteristic of a target profile of the planned switching operation and wherein the method (100) further includes: - Determining the second drive torque and / or the time to activate (130) the drive (201) in additional dependence on the target gear specification. [8] Method (100) according to claim 7, characterized by , that with an increasing transmission ratio of the target gear characterized by the target gear specification, the second drive torque is chosen to be increasingly lower. [9] Method (100) according to any one of the preceding claims, characterized by , which further includes: - Controlling the drive (201) such that the drive torque provided by the drive corresponds again to the first drive torque, in particular by the control unit (203). [10] Pedal-driven vehicle (200) comprising at least one drive (201) for providing a drive torque for propelling the pedal-driven vehicle (200), a gearshift (202) for providing a variable transmission ratio and a control unit (203), wherein the pedal-driven vehicle (200) is configured to be operated according to a method (100) according to one of the preceding claims. [11] Computer program product comprising instructions that cause a pedal-driven vehicle (200) according to the preceding claim to execute a method (100) according to any one of claims 1 to 9. [12] Computer-readable medium on which a computer program product according to the preceding claim is stored. [13] Data carrier signal which transmits a computer program product according to claim 11.

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