US Patent 8704387 Electrical energy generator

An electrical energy generator comprising a housing having a longitudinal axis and opposite ends, an electromagnetically active mass positioned within the housing reciprocally movable along at least a portion of the longitudinal axis, an electrically conductive material within the housing, a body engaged with the electromagnetically active mass, and at least one spring positioned between at least one of an end of the housing and an end of the body, or between an end of the body and the electrically conductive material.