Abstract: A gas cylinder valve with minimum wetted area has a one-piece valving assembly comprising a valve member, a non-perforated diaphragm member and a valve stem, the latter including a threaded stud and a stem shaft threaded on to the stud. The threaded stud, diaphragm member and valve member are fused together by a YAG laser weld applied through a central, blind bore in the valve member. Another through weld is applied around the peripheral edge of the threaded stud. A rim on the stem shaft clamps the diaphragm outside the peripheral weld through a pair of washers which absorb the torsional load. A helical compression spring bears on a valve stem shaft shoulder outside the wetted area to bias the valve open. A resilient bushing supported by a metal cup backs up the diaphragm member.

Abstract: A refueling check valve assembly which provides for rapid, efficient, and safe refueling of compressed natural gas powered vehicles is provided and includes a receptacle adapted to mate with a fuel supply nozzle and a valve body having first and second gas flow passages therethrough. The respective first ends of the first and second gas flow passages communicate with the receptacle, while the respective second ends of the first and second gas flow passages are adapted to communicate with a fuel storage vessel, typically through a fuel supply line. A check valve is positioned in the first gas flow passage of the valve body and is normally biased into a closed position to prevent the flow of gas through the first gas flow passage. The check valve opens in response to a flow of fuel under pressure, permitting the flow of gas to the fuel storage vessel. A by-pass valve is also provided in the second gas flow passage in the valve body for depressurizing the fuel system prior to servicing.