Abstract: A fuel tank cap for use in a motor vehicle including a cap body having a path communicating the interior of a fuel tank with the atmosphere and having incorporated therein a sensor valve unit. The sensor valve unit includes a valve housing having an upper wall with a first through-opening therein open to the path for communication with the atmosphere, a peripheral wall with a second through-opening at a predetermined position which is open to the housing interior and communicates with the fuel tank interior, an upright funnel shaped bottom wall, a weight ball movably positioned on the bottom wall, and a valve body resting on the weight ball so as to be moved upwards for closing the first through-opening when the weight ball rolls over the bottom wall and thereby carries out an upward movement.

Abstract: A device for capping a supplying opening of a fuel-tank of a motor vehicle or the like, comprises a capping outer casing of T-shaped cross section, and cylinder-lock means centrally mounted inside the outer casing for holding and releasing a locking condition, wherein although a distance frictionally driven by respective projections mounted on a rotary member against resilient force is fully, automatically relaxed to permit respective locking bars to be projected for locking and thus, the device is locked when a key fitted in cylinder-lock means is left in a free condition, the key fitted is arranged to be not detachable from cylinder-lock means without further manual actuation thereof in the same direction of the free returning direction thereof.

Abstract: Motor vehicle fuel tank cap of the air bleeder type which includes passages permitting external air to enter a fuel tank and so maintain air pressure in the tank at a level permitting correct feed of fuel to the motor vehicle engine and which includes an attitude-sensor valve unit which when the motor vehicle becomes inclined more than a certain amount with respect to the vertical closes the air passages, whereby leakage of fuel to the exterior of the fuel tank is prevented and risk of accident is avoided.