Patent ID: 7188613

Claim:
A cut off valve that is to be attached to an upper portion of a fuel tank and opens and closes a connection conduit for connecting an inside of the tank to outside of the tank according to a fuel level in the fuel tank, the cut off valve comprising: a casing including (i) a first valve chamber that is connected to the inside of the fuel tank, (ii) a second valve chamber that is connected to the first valve chamber, (iii) a first connection conduit that connects the first valve chamber and the second valve chamber, and (iv) a second connection conduit that connects the second valve chamber to the outside; a first valve mechanism, housed within the first valve chamber, that closes the first connection conduit when the fuel level rises to reach a first liquid level; a second valve mechanism, housed in the second valve chamber, that closes the second connection conduit when the fuel level reaches a second liquid level that is higher than the first liquid level; and a restriction path, disposed between the first valve chamber and the second valve chamber, that reduces the flow from the first valve chamber to the second valve chamber so as to increase the pressure within the fuel tank when the first valve mechanism closes the first connect conduit.