| 摘要 |
PURPOSE:To attain smooth conversion from starting to synchronized operation of a synchronous motor by a method wherein widths and the setting angles in the circumferential direction of brushes, and the developing angle of a slip ring are made to have a fixed relation, and the rotating angle of a rotor to send an electric current to one side out of two coil segments is enlarged. CONSTITUTION:An armature coil 10 consisting of the two coil segments 10a, 10b is provided to a permanent magnet of four poles, while a converting circuit consisting of the slip ring 14 consisting of slip ring segments 14a, 14b, the brushes 12a-12d, and commutators 16a, 16b is provided. When starting operation is to be performed, an AC electric power source 18 applied with full-wave rectification is fed alternately to the respective coil segments 10a, 10b, and when synchronized operation is to be performed, the AC electric power source 18 is fed directly to the whole of the coils through switches 20a, 20b. The circumferential angles of the slip ring segments 14a, 14b are made as a little smaller than 180 deg., the brushes 12a, 12b are arranged approaching the brush 12c side, or width of the circular arc of the brush 12c is enlarged, and the rotating angle of the rotor to send the electric current to the coil segment 10a is made larger than the other side. |
