| 摘要 |
PURPOSE:To perform a complete sparkless commutation in a DC electric machine by providing two commutators and interposing a diode so that currents respectively flow from one commutator to an armature coil and from the other commutator to an armature coil. CONSTITUTION:A commutator 4 which is formed of commutator pieces 41 and interpiece insulators 42, and a commutator 4'' which is formed of commutator piece 41'' and interpiece insulators 42'' are provided. Diodes 61, 61'' are interposed between armature coil group 3 (only coil segments #3, #3' are indicated) and the commutator pieces 41, 41''. Thus, currents respectively flow from the armature coil group 3 to the commutator 4 and from the commutator 4'' to the armature coil group 3. The commutator 4 is connected via a brush (not shown) to the negative side of a power source, and the commutator 4'' is connected via a brush to the positive side of the power source. In case of a generator, the connection is performed in reverse direction. Since the circulating currents forcibly become zero before the end of the rectification, it becomes sparkless. |
