PURPOSE: To enable operation of low power consumption without using electromagnet.
CONSTITUTION: An electret film 3 equipping a conductive layer 4 on one side is provided so that a part of the conductive layer 4 touches to the first terminal 1, and that a movable part is formed at the lower part. An opposite electrode 5 is provided facing to the electret film 3, and voltage is applied between the first terminal 1 and the opposite electrode 5 so that an electric potential of the opposite electrode 5 and an electric potential of the electret film 3 become the same polarity. The movable part of the electret film 3 operates due to electric repulsion operated to the electret film 3, then the conductive layer 4 and the second terminal 2 contacts, an energized condition is formed between the first terminal 1 and the second terminal 2.
ITO TAKAYUKI