Patent ID: 7737608

Claim:
An electrically driven actuator apparatus, comprising: an electronically responsive piezoelectric wafer; a support for supporting said piezoelectric wafer while allowing oscillating motion of a midpoint of said piezoelectric wafer; and a biasing element operatively associated with an end of said piezoelectric wafer for applying a compressive pre-load force to said end of said piezoelectric wafer sufficient to deflect said midpoint of said piezoelectric wafer into one of two stable non-linear orientations, and to assist in moving said midpoint between said two stable non-linear positions; and said biasing element associated with said end of said piezoelectric wafer being free to flex in an arcuate path in response to vibration experienced by said piezoelectric wafer, to enhance a sensitivity of the piezoelectric wafer and oscillating motion of said midpoint of said piezoelectric wafer in response to said vibration.