Abstract: There is an apparatus for regulating air flow into a rim mounted pneumatic vehicle tire. The apparatus has an elongated valve housing 1? with an inlet end 1A?, an outlet end 2? and a central portion between the outlet and inlet. The outlet end includes a rim insertion portion 3? configured to fit into an aperture in the tire rim. There is a piston 8? disposed within the housing. The piston includes a valve member 19?. A coil spring 22? acts between the housing and piston so that in use of the apparatus the piston is biased to a open position for passage of air into the tire and is movable against the spring bias under air pressure build-up in the tire to a closed position at which the valve member seals against a valve seat. The piston and spring are located in the central portion of the housing clear of the rim insertion portion. The rim insertion portion is of a reduced size not obstructive to the mounting of the tire.

Abstract: There is an apparatus for regulating air flow into a rim mounted pneumatic vehicle tyre. The apparatus has an elongated valve housing 1′ with an inlet end 1A′, an outlet end 2′ and a central portion between the outlet and inlet. The outlet end includes a rim insertion portion 3′ configured to fit into an aperture in the tyre rim. There is a pistion 8′ disposed within the housing. The piston includes a Valve member 19′. A coil spring 22′ acts between the housing and piston so that in use of the apparatus the piston is biased to a open position for passage of air into the tyre and is movable against the spring bias under air pressure build-up in the tyre to a closed position at which the valve member-seals against a valve seat. The piston and spring are located in the central portion of the housing clear of the rim insertion portion. The rim insertion portion is of a reduced size not obstructive to the mounting of the tyre.