Abstract: An inner diameter of a filler tube is formed smaller than that of a filler neck of a tank main body. Hence, a clearance is thus difficult to be created between inner peripheral surface of the filler tube and the fuel stream which flows through the filler tube upon supply of fuel, and also leakage of vapor fuel from a fuel filler port can be avoided. In addition, a cylindrical insert whose inner diameter is formed to be substantially equal to its of the filler tube is provided in a neck portion of the filler hose. Accordingly, there exists no portion where the inner diameter is largely changed in the filler neck portion, whereby generation of turbulent flow of the supplied fuel and reduction in a flow rate can be suppressed to their maximum and thus fuel supply performance can be enhanced.

Abstract: A canister structure for absorbing fuel vapor in the fuel tank and supplying the fuel vapor into the engine together with purge air is provided. The canister structure includes a canister body filled up with absorbents for absorbing the fuel vapor, a purge pipe connected to the canister body for introducing the purge air into the canister body and a separator for removing moisture contained in the purge air. To the separator, the purge pipe is connected downwardly. The separator is provided on the bottom side with an air inlet of which diameter is larger than that of the purge pipe. With the above-mentioned arrangement, since the separator is so formed as to have a diameter larger than that of the purge pipe, it is possible to reduce a flowing speed of the purge air by means of the separator, so that moisture contained in the purge air can be trapped and eliminated by the separator certainly.

Abstract: The fuel tank system comprises a tank body for containing fuel therein, a canister for disposing said fuel component, a filler tube connected with the tank body and forming a channel for supplying fuel to the tank body, a vent side check valve having a first chamber and a second chamber separated by a diaphragm, a signal tube connecting the first chamber of the vent side check valve with the upper part of the filler tube, a vent side tube for connecting the tank body with the canister via the second chamber of the vent side check valve and for introducing a gaseous body containing fuel component in the tank body to the canister via the second chamber when filling fuel, and an orifice for the signal tube, provided on the upper part of the signal tube on the filler tube side and having such an inside diameter and a length that may prevent the fuel permeation into the signal tube side from the filler tube side.