Patent attributes
A rod is sawtooth-like vibrated by cyclically applying, to a piezoelectric element, voltage values which are stepwise and sequentially increased or decreased, so that a moving unit is driven along the rod in one direction or the opposite direction. The sequentially increased or decreased voltage values are generated by controlling of turning “on” or “off” of a plurality of switching elements, which are disposed in a circuit arrangement, wherein the piezoelectric element, and 1st and 2nd capacitors are arranged between a positive power supply and a negative power supply. When the 1st capacitor has a parallel positional relationship with the piezoelectric element and the 2nd capacitor serially connected, a switching element serially connected to the 1st capacitor is opened. When the 2nd capacitor has a parallel positional relationship with the piezoelectric element and the 1st capacitor serially connected, a switching element serially connected to the 2nd capacitor is opened.
