Patent ID: 7432637

Claim:
A piezoelectric drive device, comprising: a case; and a drive unit body movable relative to the case, wherein the drive unit body includes: a displacement expanding plate; a biasing unit; and a piezoelectric element attached to the displacement expanding plate, the displacement expanding plate includes: a body adapted to rotate or slide relative to the case, the body biased by the biasing unit; and a displacement expanding portion expanding a displacement when the piezoelectric element is expanded due to a voltage application, the displacement expanding portion being displaced relative to the body in a direction perpendicular to an expanding direction of the piezoelectric element, in a state where no voltage is applied to the piezoelectric element, a first driven object is moved by the body that is biased by the biasing unit, when the voltage is applied to the piezoelectric element, a second driven object is moved by the displacement expanding portion, and when the voltage is further applied to the piezoelectric element in a state where the second driven object abuts on an object such that the displacement of the displacement expanding portion is expanded, the body and the first driven object are moved against a biasing force of the biasing unit in a direction opposite to a biasing direction of the biasing unit.