Patent ID: 6693852
Filing Date: 2004-02-17
Classification: G04C

Abstract:
An electronic device, comprising:a mechanical energy source; a generator having two terminals, and configured to be driven by the mechanical energy source, to generate induced electrical power, and to provide electrical energy; and a rotation controller configured to be driven by the electrical energy, and to control a rotation period of the generator, the rotation controller including a switch that is able to selectively connect the terminals of the generator in the form of a closed loop, a chopping signal generator configured to generate a chopping signal that is applied to the switch for brake control of the generator, and a brake controller configured to control the chopping signal generator, and thereby control a braking force applied to the generator, by selectively switching between at least three brake control modes, including a high-power brake control mode in which an effective braking force is large, a mid-power brake control mode in which the effective braking force is less than the effective braking force of the high-power brake control mode, and a low-power brake control mode in which the effective braking force is less than the effective braking force of the mid-power brake control; wherein the mid-power brake control mode is performed in a first transitional period during which the low-power brake control mode is switched to the high-power brake control mode, or in a second transitional period during which the high-power brake control mode is switched to the low-power brake control mode, or in both the first and second transitional periods.