PURPOSE: To enable automatic assemble by temporarily fixing a coil spring onto a cover plate in a state that the spring is deflected by a definite quantity in advance so as to be formed into an unit.

CONSTITUTION: While an energizing coil spring 7 is interposed between hook sections 12a and 12b provided for a cover plate 12 in a state that it is deflected to a definite dimension in advance, respective parts are incorporated in a box shaped base 1 in a state that no force pushing a sliding body is exerted by the coil spring 7, the coil spring 7 is then released from the hook section 12b with an actuating lever 14 operated while the cover plate 12 is being completely fixed, normal automatic reset type slide switch operation can thereby be performed. This thereby prevents the parts from coming out by the force of the energizing coil spring 7 when the respective parts are incorporated in the box shaped case 1, thereby facilitating the incorporation of the respective parts in the switch case so that the respective parts can also be automatically assembled.