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 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 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 spring acts in tension and 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 spring acts in tension and 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.