| 摘要 |
PURPOSE:To rapidly decelerate from a high speed rotation to a low speed rotation by providing a driving circuit which inputs output signals from an absolute value amplifier and an inverter and drives to energize a motor coil CONSTITUTION:When a rotating speed is intended to be decelerated, a control signal Vct1 is abruptly lowered to a '0' level and maintained for a predetermined time. When the signal Vct1 becomes the '0' level through a reference signal, an absolute value amplifier 11 maintains a predetermined level, but the output of an inverter 12 becomes an 'L' level. A driving circuit 25 sequentially reversely energizes coils 37, 38, 39 and supplies a large current in response to the output level of the amplifier 11. Thus, a motor is fully braked, and when the motor is decelerated to the vicinity of a target, the signal Vct1 is gradually raised toward a target value. Thus, the output of the amplifier 11 is gradually lowered to gradually lower a brake force. When the motor becomes a predetermined low speed, it is maintained at a predetermined target value higher than the signal Vct1. |
