| 摘要 |
PURPOSE:To obtain a driving apparatus which smoothly changes over a driving current given to driving coil and reduces vibrations when a motor is driven by a method wherein a counter electromotive-force detector which detects a counter electromotive force generated in the driving coil so as to be waveform- shaped is provided with a mask-signal generator which generates a signal used to mask a phase. CONSTITUTION:Voltage waveforms U, V, W and output signals P1 to P6 from a mask-signal generator 12 are input to a counter-electromotive-force detector 10, and U1, V1 and W1 are output so as to be inputted to a trapezoidal-wave current composition device 11. The trapezoidal-wave current composition device 11 generates current outputs IPL1 to IPL3, IPU1 to IPU3, and a trapezoidal motor-position signal is obtained. Then, a current distribution circuit 13 sequentially supplies a driving current to driving coils 1 to 3, and a motor is turned. Thereby, since only the signal of the counter electromotive force according to the rotation of the motor can be detected, the driving current which drives the driving coils can be changed over smoothly, and it is possible to reduce vibrations when the motor is turned. |
