Patent ID: 7686030

Claim:
A cut valve which is installed on a fuel tank and is adapted to shut off a vent passage between the interior of the fuel tank and the outside when a fuel level in the fuel tank has risen, comprising: a housing including: a cover having a lead-out pipe connectable to an external pipe; a tubular body provided with a ceiling portion connected to a lower side of the cover and having a vent hole communicating with the lead-out pipe; and a bottom portion closing a lower surface of the tubular body; and a float valve which is slidably accommodated in the housing and is adapted to open or close the vent hole by coming into contact with and moving away from a valve seat provided at a peripheral edge of the vent hole in the ceiling portion, said float valve comprising ribs formed along an axial direction on an outer periphery of the float valve and projecting upwardly of an upper surface of the float valve, said ribs comprising projecting portions, wherein the ceiling portion of the tubular body is formed to have: the valve seat that defines the vent hole; a protruding portion that is formed radially outward from the valve seat to protrude toward the float valve; and a recessed portion that is formed of radially outward from the protruding portion, said projecting portions being configured to insert into said recessed portion, wherein a radial width of the protruding portion is wider than that of the recessed portion, wherein a size of said projecting portions in an upward direction from the upper surface of the float valve is larger than an interval between the upper surface of the float valve and the protruding portion of the tubular body in a state in which the float valve has floated up to close the vent hole, wherein both of the upper surface of the float valve and a lower surface of the protruding portion are formed in a substantially planar-shape, and wherein, in a state where the float valve has floated up to close the vent hole, the upper surface of the float valve and the lower surface of the protruding portion are substantially in parallel with each other, and further comprising an annular rib extending upright from said ceiling portion of said tubular body, said annular rib surrounding said valve seat.