PURPOSE: To offer a displacement element of a little power consumption, little heat radiation and capable of holding its displaced state without using a holding device, and a relay device using it by utilizing a ferroelectrics shape-memory ceramic element which is digitally displaced by a phase change from antiferroelectric to ferroelectric phase induced by application of a predetermined electric field and which maintains its ferroelectric phase even after the electric field is cut off.
CONSTITUTION: Shape-memory ceramic elements 1, 2 are formed and silver electrodes 3, 4, 5 are combined to each of the elements, and the two shape-memory ceramic elements are stuck to each other and are held by a holding member 6 whereby a displacement element 10 is manufactured. A voltage of about 500V is applied to only the shape-memory ceramic element 1 via electrodes 4, 5. The shape-memory ceramic element 1 is then digitally displaced in the X direction by a phase change from antiferroelectric to ferroelectric phase. Thereafter, even when the applied voltage is 0, the shape-memory ceramic element 1 will not return to its initial state but maintains its ferroelectric phase and holds its displaced state, and exhibits its shape memory property. In order to convert the shape-memory ceramic element to its initial state, a reverse voltage of about 100V must be applied.
YODA SEI