PIEZOELECTRIC DEVICES

摘要

A piezoelectric device comprising a plurality of elements (1) of piezoelectric material operable in shear mode to cause shear between two opposed surfaces of the element. The elements (1) are coupled such that the shear of the elements causes torsion in the device. Several different arrangements for a group of elements (10, 30, 50) to cause such torsion are disclosed. Several devices (20, 40, 60, 70) which utilise the groups of elements as torsional actuators in series are also disclosed. In these devices, the torsional actuators formed by the elements of piezoelectric material operable in shear mode may be replaced by other piezoelectric torsional actuators.