Electric bicycle transmission systems, methods, and devices
First Claim
1. A derailleur-based electronic transmission system for an electric bicycle, the system comprising:
- a wheel;
a driven sprocket set coupled to the wheel via at least a first one-way clutch, the driven sprocket set comprising two or more concentric sprockets of different effective diameters;
a drive chain configured to engage the driven sprocket set;
an electronically controllable derailleur configured to move the drive chain among the two or more sprockets;
a pedal crank configured to cause rotation of the driven sprocket set by providing a user pedal force to the driven sprocket set through at least a second one-way clutch and the drive chain;
a motor configured to cause rotation of the driven sprocket set by providing an electromechanical force to the driven sprocket set through at least a the drive chain; and
an electronic controller configured to, responsive to a determination that a shift should occur at a time when neither the pedal crank nor the motor is causing rotation of the driven sprocket;
operate the motor to rotate the driven sprocket at a rotational speed less than or equal to a current rotational speed of the wheel; and
operate the derailleur to cause the shift to occur while the driven sprocket is being rotated by the motor.
1 Assignment
0 Petitions
Accused Products
Abstract
A derailleur-based electronic transmission system for an electric bicycle comprises a wheel; a driven sprocket set coupled to the wheel via at least a first one-way clutch, the driven sprocket set comprising two or more concentric sprockets of different effective diameters; a drive chain configured to engage the driven sprocket set; an electronically controllable derailleur configured to move the drive chain among the two or more sprockets; a pedal crank configured to cause rotation of the driven sprocket set by providing a user pedal force to the driven sprocket set through at least a second one-way clutch and the drive chain; a motor configured to cause rotation of the driven sprocket set by providing an electromechanical force to the driven sprocket set through at least a the drive chain; and an electronic controller configured to, responsive to a determination that a shift should occur at a time when neither the pedal crank nor the motor is causing rotation of the driven sprocket: operate the motor to rotate the driven sprocket at a rotational speed less than or equal to a current rotational speed of the wheel; and operate the derailleur to cause the shift to occur while the driven sprocket is being rotated by the motor.
81 Citations
20 Claims
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1. A derailleur-based electronic transmission system for an electric bicycle, the system comprising:
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a wheel; a driven sprocket set coupled to the wheel via at least a first one-way clutch, the driven sprocket set comprising two or more concentric sprockets of different effective diameters; a drive chain configured to engage the driven sprocket set; an electronically controllable derailleur configured to move the drive chain among the two or more sprockets; a pedal crank configured to cause rotation of the driven sprocket set by providing a user pedal force to the driven sprocket set through at least a second one-way clutch and the drive chain; a motor configured to cause rotation of the driven sprocket set by providing an electromechanical force to the driven sprocket set through at least a the drive chain; and an electronic controller configured to, responsive to a determination that a shift should occur at a time when neither the pedal crank nor the motor is causing rotation of the driven sprocket; operate the motor to rotate the driven sprocket at a rotational speed less than or equal to a current rotational speed of the wheel; and operate the derailleur to cause the shift to occur while the driven sprocket is being rotated by the motor. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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12. A method of automatically operating a derailleur-based transmission of an electric bicycle, the method comprising:
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determining, by an electric bicycle controller, that a stop event is occurring; determining, by the electric bicycle controller, that a downshift is desirable before the stop event completes; measuring, directly or indirectly, a rotational sprocket set speed and determining that the rotational sprocket set speed is below a threshold speed for effecting the downshift before the stop event completes, the sprocket set comprising two or more concentric sprockets; operating, by the electric bicycle controller, a motor to cause rotation of the sprocket set at a speed equal to or greater than the threshold speed, but equal to or less than a rotational speed of a wheel coupled to the sprocket set; and operating, by the electric bicycle controller, an electronic derailleur to cause the electronic derailleur to shift a chain from a first sprocket of the two or more concentric sprockets to a different sprocket of the two or more concentric sprockets while the motor is causing the sprocket set to rotate. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19)
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20. A computer-readable, non-transitory storage medium having a computer program stored thereon for causing a suitably programmed computer system to process by one or more processors computer-program code by performing a method for automatically operating a derailleur-based transmission of an electric bicycle when the computer program is executed on the suitably programmed computer system, the method comprising:
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determining, using a computer system, that a stop event is occurring; determining, by the computer system, that a downshift is desirable before the stop event completes; measuring, directly or indirectly, a rotational sprocket set speed and determining that the rotational sprocket set speed is below a threshold speed for effecting the downshift before the stop event completes, the sprocket set comprising two or more concentric sprockets; operating, using the computer system, a motor to cause rotation of the sprocket set at a speed equal to or greater than the threshold speed, but equal to or less than a rotational speed of a wheel coupled to the sprocket set; and operating, using the computer system, an electronic derailleur to cause the electronic derailleur to shift a chain from a first sprocket of the two or more concentric sprockets to a different sprocket of the two or more concentric sprockets while the motor is causing the sprocket set to rotate; wherein the computer system comprises a computer processor and electronic memory.
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Specification