Patent attributes
A gas pressure regulator of the kind in which a valve member is spring biased to the valve-open position and is moved to the valve-closed position when upstream pressure at an outlet overcomes the spring is arranged such that gas pressure at an inlet end of the valve member 12 does not influence it in the valve-opening direction. In the embodiment of FIGS. 3 and 4 a bottom end of the valve member receives a piston-like plug. Openings in the wall of the valve member are occluded when the valve is closed. In the open position of the valve member pressure is equal all round each opening. In another embodiment of the invention a spool is provided having one enlarged end within the valve member and another outside it. Pressure on the combined surfaces of the end and the end of the valve member is equal to the pressure on the end of the spool.