Hub dynamo for e.g. bicycle front wheel, has exciting electric circuit that supplies rotor coil with current from generator electric circuit, and interruptible electrical connection provided between circuits

摘要

The dynamo has a magnetic rotor (12) that comprises of a rotor coil (10) with a weak permanent magnetic core. An exciting electric circuit supplies a rotor coil with current from a generator electric circuit. An interruptible electrical connection (14) is provided between the generator electric circuit and an exciting electric circuit. A switch is provided to establish and interrupt an electrical connection between the electric circuits. An external electronic circuit of the exciting electric circuit is provided such that it controls the output voltage of the hub generator.