Patent ID: 7161278
Filing Date: 2007-01-09
Classification: H02N

Abstract:
1. Piezoelectric actuator, comprising: a body; a peristaltic actuating element, extended in a main motion direction; the peristaltic actuating element in turn comprising: an interaction surface with the body; volumes of piezoelectric material; electrodes for excitation of the volumes of piezoelectric material; means providing normal forces between said body and said peristaltic actuating element; and control means for supplying voltage signals to the electrodes; the volumes of piezoelectric material and the electrodes being arranged to cause the peristaltic actuating element to change a dimension difference between the peristaltic actuating element and the body, the control means being arranged to supply voltage signals causing borders of a peristaltic section within which the dimension change is present to move substantially continuously along the peristaltic actuating element parallel to the main motion direction, the change of the dimension difference between the peristaltic actuating element and the body having a component in a dimension essentially parallel to the main motion direction, and the volumes of piezoelectric material and the electrodes being arranged to further cause the interaction surface within the peristaltic section to be removed from the body to be moved within the peristaltic section simultaneously as the change in dimension difference parallel to the main motion direction.