To secure the smoothness of the float and sink movement of a float in a cutoff valve.
An inner float 80 engages an annular protrusion 84 with the upper end of an engagement arm part 68 after entering the annular protrusion 84 into a through-hole 66 provided to an outer float 60, and integrates with the outer float 60. The engagement arm part 68 extends from an opening side circumference part 72 of a float lower end side to the lower end of the through-hole 66, and makes an end part peripheral wall 69 an inclined plane. Therefore, this engagement arm part 68 is hardly brought into contact with a projection strip 43 guiding the float and sink movement of the float in a valve chamber 42 even if the engagement arm part 68 is deformed to the float peripheral side from the opening side circumference part 72.
NISHI HIROSHI
HORIBA SHOJI
