| 摘要 |
PURPOSE:To obtain easy operation of switching directions of rotation of a brushless motor, by operating gamma-shift for reducing armature reaction with switching output between position detectors, with the position detectors fixed at a constant position. CONSTITUTION:Output signal of position detectors HA-HC are amplified by comparing amplifiers 10-12 and are put into a switching circuit G. In the switching circuit G, linking switches 13-15 select with respect to the output signals HA'-HC' given by the comparing amplifiers 10-12 combinations of HA' HC', HB' HA' and HC' HB'. When normal rotation is required the switches 13-15 are connected so as to have a=HA', b=HB' and c=HC'. When reverse rotation is required the switches 13-15 are changed over so as to have a=HC', b=HA' and c=HB'. Thus with both rotating directions gamma-shift of gamma=30 deg. is effectively provided, and an adverse effect of armature reaction is reduced. |
