a female screw member includes a female screw part with a female screw , and a projection part projecting in the direction of a center shaft of the female screw and having a working face in the rotating direction centering on the center shaft . the female screw part and projection part are integrally molded with a resin . the projection part has a spiral inclination face spirally inclining by one round from the working face centering on the center shaft of the female screw . the height h of the working face is equal to or smaller than a pitch p of the female screw . using the projection part as a fully opening fixing stopper , a motor operated valve includes a valve main body having a valve seat , the female screw member attached to the valve main body , a motor having a rotator and stator , and a valve shaft . the valve shaft is screwed to a female screw of the female screw member , and is rotated and driven by the rotor , and has a fully opening movable stopper capable of contacting the fully opening fixing stopper .