Abstract: A gas pressure regulator includes a throttle valve provided between a gas inlet passage having an orifice formed therein and a pressure sensing chamber pertaining to a gas exit passage, the throttle valve having a sealing plug fluidically drafted upwardly for closing a truncated cone hole of the throttle valve when subject to a surge gas flow of great volume rate due to a gas leakage from a downstream gas line for safety reason, and gravitationally dropping by a gravity of the plug for re-opening the throttle valve for continuous gas supply when just opening a valve of a gas source.

Abstract: A gas pressure regulator includes a throttle valve provided between a gas inlet passage and a pressure sensing chamber pertaining to a gas exit passage, the throttle valve having a sealing plug comprised of a needle and a base float fluidically drafted for closing a truncated cone hole of the throttle valve when subject to a surge gas flow of great volume rate due to a gas leakage from a downstream gas line for safety reason, and upon a simple restoring of the plug for re-opening the throttle valve, a gas stream can be continuously supplied when just opening a valve of a gas source.

Abstract: In a gas pressure regulator a switch valve is provided in a throttle nozzle between an inlet passage and a pressure sensing chamber containing a diaphragm controlling a lever arrangement. The pressure regulator is capable of both pressure reduction and automatic shut off if there is a leak due to gas line damage or other conditions. Preferably a restoring mechanism is provided to reset the regulator after its automatic shut off.