Patent attributes
A driving device, small in size and light in weight, is to stabilize the position of a surface-deforming element while reducing the effect of gravity thus enabling stable transfer and positioning. The driving device is structured to hold a movable member integrated with a piezoelectric vibrator and a lens by a shaft provided at a tip of a spring extended from an inner surface to center of a passageway. The shaft extends through an opening formed in a protrusion of the movable member. By a tensile force of the spring, the movable member at its outer periphery is pulled radially and held. When applying a voltage with a waveform changing sharply to the piezoelectric vibrator, the movable member flexes maximally upward or downward to have a reduced diameter and an increasing acceleration thereby making a movement. Then, when a frictional force increases, the protrusion is held at a point where the movable member moves. Because of being held by a tensile force, the effect of gravity decreases and hence the movable member is stabilized in position relative to a direction of transfer.
