振動発電素子

摘要

In a vibration power generator, an electret group is provided on a movable member while an electrode group is provided on a fixed member. The vibration power generator generates power by displacement between the movable member and the fixed member in a relative movement direction in response to an external vibration. The electret group and the electrode group are accommodated in a casing unit. A first support relatively movably supports the movable member with respect to a bottom surface of the casing unit so as to define a gap between the electret group and the electrode group. A second support supports the movable member such that the movable member is relatively movable with respect to a lateral inner wall surface of the casing unit. The lateral inner wall surface defines the relative movement direction together with the bottom surface of the casing unit. The movable member is biased toward the lateral inner wall surface of the casing unit to retain a state in which the movable member is supported by the second support during the relative movement. Therefore, a deviation between an array of electrets and an array of electrodes is maximally decreased in the vibration power generator that generates the power by relatively moving the electrets and the electrodes while the electrets and the electrodes are opposed to each other.