Abstract: A stop valve for closing a nozzle in a fluid passage comprising: a valve shaft movable in the axial direction relative to the nozzle; a solenoid attached to an end of the shaft for moving the shaft in the axial direction; an auxiliary valve consisting of a secondary valve body disposed around the shaft and a supporting part extending in the axial direction of the valve shaft and engaged with a part of the valve shaft through a spring for carrying the secondary valve body at one end and a spring-engaging portion at the other end and for moving together with the valve shaft in the axial direction; a main valve body disposed around the valve shaft between the spring-engaging portion and the secondary valve body and formed with a central aperture to be opened or closed by the secondary valve body, the main valve body being pressed against the secondary valve body by a contracted spring disposed between the spring-engaging portion of the supporting part of the auxiliary valve and the main valve body so that the ma