| 摘要 |
PROBLEM TO BE SOLVED: To make an effective driving of an oscillatory wave motor, etc., by shifting timings of switching directions of first frequency voltage and second frequency voltage of a driving means. SOLUTION: An A and an A' phase of a switching circuit are 180 deg. out of phase. The B-phase and B'-phase outputs lags A-phase and A'-phase switching pulses by 90 deg. when a dir signal is L0 and lead by 90 deg. when the dir signal is Hi. While A-phase and A'-phase waves are in a <11> state, FET's 1, 4 are turned ON and current flows as indicated by <11>. When the A phase and A'-phase waves comes to a <12> state, FET's 2, 4 are turned ON and electric charge of a piezoelectric element is discharged and thereby current flows as indicatd by <12>. When the A-phase and A'-phase waves becomes a <13> state, FET's 2, 4 are turned ON and current flows as indicated by <13>. In a state of <14>, FET's 2, 4 are turned on and electric charge is discharged and thereby current flows reversely to the <12>. As a result, unnecessary power consumption is lessened and an oscillator can be driven stably. |
