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US 11,440,618 B2Granted
Electric assist system and electric assist vehicle
AssigneeYamaha Hatsudoki Kabushiki Kaisha
InventorMitsuharu Hasumi
Life of this patent
Estimating the term…
Abstract
An electric assist system for an electric assist vehicle includes a crankshaft rotatable by human power of a rider applied to a pedal, an electric motor that generates an assist power that assists the human power of the rider, a controller that controls a magnitude of the assist power to be generated by the electric motor, and an acceleration sensor that outputs a signal in accordance with an acceleration in a traveling direction of the electric assist vehicle. The controller changes the magnitude of the assist power to be generated by the electric motor in accordance with a change in the acceleration that is associated with an operation of the rider rotating the pedal.
Claims19
An electric assist system for an electric assist vehicle including a pedal, the electric assist system comprising:
- a crankshaft that is rotatable by human power of a rider applied to the pedal;
- an electric motor that generates an assist power to assist the human power of the rider;
- a controller configured or programmed to control a magnitude of the assist power to be generated by the electric motor;
- an acceleration sensor that outputs a signal in accordance with an acceleration in a traveling direction of the electric assist vehicle;
- and
- a torque sensor that outputs a signal in accordance with a torque generated at the crankshaft;
- wherein
- the controller is configured or programmed to change the magnitude of the assist power to be generated by the electric motor in accordance with a change in the acceleration that is associated with an operation of the rider rotating the pedal;
- the torque generated at the crankshaft by the human power of the rider applied to the pedal changes in accordance with a rotation of the crankshaft;
- the controller is configured or programmed to change the magnitude of the assist power to be generated by the electric motor in accordance with a change in the acceleration that is associated with a change in the torque;
- a magnitude of the torque generated at the crankshaft by the human power of the rider applied to the pedal increases and decreases in accordance with the rotation of the crankshaft;
- and
- the controller is configured or programmed to change the magnitude of the assist power to be generated by the electric motor in accordance with a change in the acceleration between an adjacent ridge and trough of the torque that increases and decreases.
10 more elements
An electric assist system for an electric assist vehicle including a pedal, the electric assist system comprising:
- a crankshaft that is rotatable by human power of a rider applied to the pedal;
- an electric motor that generates an assist power to assist the human power of the rider;
- a controller configured or programmed to control a magnitude of the assist power to be generated by the electric motor;
- an acceleration sensor that outputs a signal in accordance with an acceleration in a traveling direction of the electric assist vehicle;
- and
- a torque sensor that outputs a signal in accordance with a torque generated at the crankshaft;
- wherein
- the controller is configured or programmed to change the magnitude of the assist power to be generated by the electric motor in accordance with a change in the acceleration that is associated with an operation of the rider rotating the pedal;
- the torque generated at the crankshaft by the human power of the rider applied to the pedal changes in accordance with a rotation of the crankshaft;
- the controller is configured or programmed to change the magnitude of the assist power to be generated by the electric motor in accordance with a change in the acceleration that is associated with a change in the torque;
- a magnitude of the torque generated at the crankshaft by the human power of the rider applied to the pedal increases and decreases in accordance with the rotation of the crankshaft;
- the controller is configured or programmed to determine a difference between a maximum value and a minimum value of the acceleration between an adjacent ridge and trough of the torque that increases and decreases;
- and
- the controller is configured or programmed to change the magnitude of the assist power to be generated by the electric motor in accordance with the difference between the maximum value and the minimum value of the acceleration.
11 more elements
An electric assist system for an electric assist vehicle including a pedal, the electric assist system comprising:
- a crankshaft that is rotatable by human power of a rider applied to the pedal;
- an electric motor that generates an assist power to assist the human power of the rider;
- a controller configured or programmed to control a magnitude of the assist power to be generated by the electric motor;
- an acceleration sensor that outputs a signal in accordance with an acceleration in a traveling direction of the electric assist vehicle;
- and
- a sensor that detects a rotation of the crankshaft;
- wherein
- the controller is configured or programmed to change the magnitude of the assist power to be generated by the electric motor in accordance with a change in the acceleration that is associated with an operation of the rider rotating the pedal;
- and
- the controller is configured or programmed to change the magnitude of the assist power to be generated by the electric motor in accordance with a change in the acceleration during a half rotation of the crankshaft.
7 more elements
An electric assist system for an electric assist vehicle including a pedal, the electric assist system comprising:
- a crankshaft that is rotatable by human power of a rider applied to the pedal;
- an electric motor that generates an assist power to assist the human power of the rider;
- a controller configured or programmed to control a magnitude of the assist power to be generated by the electric motor;
- an acceleration sensor that outputs a signal in accordance with an acceleration in a traveling direction of the electric assist vehicle;
- a sensor that detects a rotation of the crankshaft;
- and
- a sensor that detects a running speed of the electric assist vehicle;
- wherein
- the controller is configured or programmed to change the magnitude of the assist power to be generated by the electric motor in accordance with a change in the acceleration that is associated with an operation of the rider rotating the pedal;
- the controller is configured or programmed to determine whether or not conditions are fulfilled that:
- a number of rotations of the crankshaft is a predetermined number or larger;
- the running speed of the electric assist vehicle is a predetermined speed or higher;
- and
- the acceleration is of a predetermined value or larger;
- and
- when it is determined that the conditions are fulfilled, the controller is configured or programmed to decrease the assist power to be generated by the electric motor.
13 more elements
An electric assist system for an electric assist vehicle including a pedal, the electric assist system comprising:
- a crankshaft that is rotatable by human power of a rider applied to the pedal;
- an electric motor that generates an assist power to assist the human power of the rider;
- a controller configured or programmed to control a magnitude of the assist power to be generated by the electric motor;
- an acceleration sensor that outputs a signal in accordance with an acceleration in a traveling direction of the electric assist vehicle;
- a sensor that detects a rotation of the crankshaft;
- and
- a sensor that detects a running speed of the electric assist vehicle;
- wherein
- the controller is configured or programmed to change the magnitude of the assist power to be generated by the electric motor in accordance with a change in the acceleration that is associated with an operation of the rider rotating the pedal;
- the controller is configured or programmed to determine whether or not conditions are fulfilled that:
- a number of rotations of the crankshaft is a predetermined number or larger;
- the running speed of the electric assist vehicle is a predetermined speed or higher;
- and
- the acceleration is a first predetermined value or larger, and then becomes a value smaller than a second predetermined value which is smaller than the first predetermined value;
- and
- when it is determined that the conditions are fulfilled, the controller is configured or programmed to decrease the assist power to be generated by the electric motor.
13 more elements
An electric assist system for an electric assist vehicle including a pedal, the electric assist system comprising:
- a crankshaft that is rotatable by human power of a rider applied to the pedal;
- an electric motor that generates an assist power to assist the human power of the rider;
- a controller configured or programmed to control a magnitude of the assist power to be generated by the electric motor;
- an acceleration sensor that outputs a signal in accordance with an acceleration in a traveling direction of the electric assist vehicle;
- a sensor that detects a rotation of the crankshaft;
- and
- a sensor that detects a running speed of the electric assist vehicle;
- wherein
- the controller is configured or programmed to change the magnitude of the assist power to be generated by the electric motor in accordance with a change in the acceleration that is associated with an operation of the rider rotating the pedal;
- the controller is configured or programmed to determine whether or not a condition is fulfilled that:
- a predetermined time period has elapsed in a state in which a number of rotations of the crankshaft is a predetermined number or larger;
- the running speed of the electric assist vehicle is a predetermined speed or higher;
- or
- the acceleration is a predetermined value or larger;
- and
- when it is determined that the condition is fulfilled, the controller is configured or programmed to decrease the assist power to be generated by the electric motor.
13 more elements
Dependencies are inferred from the claim text.