| 摘要 |
PURPOSE:To perform reliable start/stop of such as video tape recorder, by respondind drive system quickly to the instruction for large speed reduction transfer or reverse rotation command and bringing the motor to commanded speed without substantial delay. CONSTITUTION:Saw-tooth wave generator 28 in motor servo circuit 12 provides signal e which is obtained by controlling saw-tooth peak level corresponding with signal a having frequency corresponding with the rotation of motor 10 with the output from speed command means 14 to motor 10. When reduced level of peak level of output e from saw-tooth wave generator 28 exceeds over predetermined level during speed reduction command, circuit 48 produces control signal h. Logic 22 selects exciting direction of motor from brake signal h, signal O specifying rotating direction of motor and rotating direction command signal j and provides signal p to motor exciting direction switching circuit 24. |
