Valve stem with auxiliary port
A valve stem may comprise an auxiliary port. Devices such as an air pressure gauge, a tire pressure monitoring system sensor, temperature gauges and one-way valves may be mounted to the auxiliary port. A valve stem with auxiliary port may be used in an automatic tire inflation system. A sleeve may be translatably mounted to the valve stem to cover and uncover the auxiliary port.
1. A valve comprising:
a stem having a longitudinal axis and a fluid channel formed along said longitudinal axis, the stem comprising:
a base end configured for mounting to a wheel;
a post end; and
an auxiliary port disposed between the base end and the post end, the auxiliary port being in fluid communication with the fluid channel;
a sleeve translatably disposed about the stem so as to allow closing and opening of the auxiliary port;
a first seal disposed for sealing engagement between the stem and the sleeve, the first seal being disposed about the stem between the auxiliary port and the post end;
a lock ring disposed between the first seal and the post end;
a second seal disposed for sealing engagement between the stem and the sleeve, the second seal being disposed about the stem between the auxiliary port and the base end;
a spring disposed about the stem between the second seal and the base end, the spring engaging the sleeve so as to urge the sleeve against the lock ring;
wherein when the sleeve is urged against the lock ring, the auxiliary port is closed to prevent fluid from flowing therethrough, and the first and second seals sealingly engage the stem and sleeve; and
wherein the sleeve may be forcibly translated against spring pressure along the stem away from the lock ring so as to open the auxiliary port and allow fluid to flow therethrough.
2. The valve of claim 1 further comprising a bellows having a first end and a second end, the first end of the bellows being sealed to the sleeve and the second end of the bellows being sealed to the stem between the spring and the base end.
3. The valve of claim 1 , wherein the post end and the base end of the stem are threadably joined.