TRAVEL SPEED CONTROLLER FOR ELECTRICALLY POWERED LIGHT WEIGHT VEHICLE AND ELECTRICALLY POWERED LIGHT WEIGHT VEHICLE

摘要

PURPOSE: To control acceleration of an electric bicycle and prevent run away due to a miss-operation of an accelerator. CONSTITUTION: In an electric bicycle having a motor 33 driven by a battery 43 and a speed controller 73, the speed controller comprises a brake switch 53 outputting a signal in correspond to an operation of a rear brake, a vehicle rotation sensor 51 outputting a pulse in proportion to a rotational speed of rear wheels, and a control circuit 75. The control circuit 75 calculates changes of intervals of the pulse signals coming from the wheel rotation sensor to get an acceleration value, remembers the value, and supply a driving current to the motor corresponding to the remembered acceleration value. The remembered acceleration value is revised when it is calculated that the value is exceeded and the value is eliminated when a signal from the brake switch is input. Thus, a driving speed is automatically controlled by the motor reflecting a driver's physical condition or intention but without relying on an accelerator.