US Patent 7165573 Compressed natural gas pressure regulator

A pressure-reducing regulator comprising a regulator body having an inlet port, an outlet port, and a flow path. A valve element is moved relative to a valve seat by a diaphragm assembly to control gas flow along the flow path. The regulator comprises one or more of: (a) a coalescing filter mounted in the inlet port, (b) the diaphragm assembly coupled to the valve element via a resilient member, (c) a diaphragm chamber comprising a non-constant depth in the regulator body along its diameter, (d) an aspirator tube extending into the outlet port from a passage between the diaphragm chamber and the outlet port, or (e) the valve seat comprising an inner seat and a protective covering over the inner seat.