Patent ID: 7934514

Claim:
A fuel cutoff valve that is mounted on an upper wall of a fuel tank and opens and closes a connecting passage to connect the fuel tank and outside, the fuel cutoff valve comprising: a casing having (i) a valve chamber, which is formed by an upper wall and a side wall (ii) a connecting passage-forming projection, which projects downward from a center portion of the upper wall and is perforated by the connecting passage, which connects to the valve chamber, and (iii) a seal portion located to face the connecting passage and formed on a lower end of the connecting passage-forming projection in an annular configuration; and a float mechanism having (i) a float that is housed within the valve chamber and rises and falls according to a fuel level within the valve chamber, and (ii) a seat member that is installed on an upper portion of the float and has a seat portion formed of flexible material for opening and closing the connecting passage, wherein the float includes a flexural depression-enabling recess situated on the upper portion of the float at a location in opposition to the seal portion for enabling the seat portion to undergo flexural depression when the seat portion is pressed by the seal portion, the casing has a regulating portion formed on an outer circumference of the seal portion, for regulating a level of elastic deformation at which the seat portion elastically deforms into the flexural depression-enabling recess, the regulating portion is configured to abut against the upper surface of the seat portion for regulating the upward movement of the float, when the seat portion of the seat member is elastically deformed and seated on the seal portion, the regulating portion surrounds the seal portion and is configured to contact an outermost peripheral part of the seat portion, and wherein the seat member is fixed to the float mechanism so that the seat member moves vertically together with the float, and wherein the seat member is fitted into a hole formed in a center of the float.