Abstract: A self-closing filler cap (1) is provided for a fuel tank filler neck, wherein the neck includes a restrictive flap hinged thereto, the filler cap comprising a closure ring (2) for detachable mounting on the filler neck and a closure flap assembly (3) rotatively arranged on the closure ring (2), said closure flap assembly (3) comprising an annular member (12) and a closure flap (15) hinged thereto and a locking ratchet mechanism including at least one detent spring (18) and lugs (7) such that the closure flap assembly (3) is rotatable in one direction only wherein the at least one detent spring (18) and the lugs (7) are provided on the annular member (12) and the closure ring (2) respectively.

Abstract: A self-closing cap for the fuel filler neck of a vehicle is provided which is particularly adapted for use with an automatic gas filling machine. The cap comprises a closure ring having an annular body and screw threads or bayonet lugs for detachably mounting the periphery of the annular body around the open end of the filler neck, and a closure flap assembly formed from a circular member with a nozzle receiving opening, a closure flap spring biased over the opening, and a pivotal mounting connecting the flap over the opening. The closure flap assembly includes a locking ratchet mechanism for securing the circular member over the closure ring in a selected angular position such that the pivotal mounting is substantially 180.degree. opposite from the pivotal connection of the restrictive flap within a filler neck of a vehicle to allow a fuel nozzle from an automatic gas filling machine to be smoothly inserted into and withdrawn from the self-closing cap.

Abstract: A self-closing cap for the fuel filler neck of a vehicle is provided which is particularly adapted for use with an automatic gas filling machine. The cap comprises a closure ring having an annular body and screw threads or bayonet lugs for detachably mounting the periphery of the annular body around the open end of the filler neck, and a closure flap assembly formed from a circular member with a nozzle receiving opening, a closure flap spring biased over the opening, and a pivotal mounting connecting the flap over the opening. The closure flap assembly includes a locking ratchet mechanism for securing the circular member over the closure ring in a selected angular position such that the pivotal mounting is substantially 180.degree. opposite from the pivotal connection of the restrictive flap within a filler neck of a vehicle to allow a fuel nozzle from an automatic gas filling machine to be smoothly inserted into and withdrawn from the self-closing cap.