To completely prevent air from leaking out from a conduit tube, which protects an electrical wire connecting an electrical equipment and a power source, and to easily and reliably electrically connect the electrical equipment and the power source in an air shelter. A pump and a motor are covered with a cover body, and an electrical wire that connects an explosion proof connector and a power source is not protected with a flexible conduit tube in the inside of the cover body, and protected with the flexible conduit tube only on the outer side of a conduit tube connector arranged on a side wall of a base.