Abstract: The present invention provides a supplementary pressure regulator that can be used with conventional single or multi-stage pressure regulators. It may also conveniently be used with a novel two stage balanced pressure regulator to form a three-stage vacuum demand pressure regulation system which may be used to regulate the pressure of compressed gases used as fuel in engines, such as natural gas used in natural gas powered vehicles. The pressure regulator of the present invention is a robust, compact, high flow, low droop, low pressure drop, low set-point drift and low creep regulator which is suitable for both OEM and after market use. It is particularly useful in mono-, bi-, and dual fuel engine applications.

Abstract: The present invention provides an improved two-stage pressure regulators for various compressed gases, and more particularly to pressure regulators used for gaseous fuels such as compressed or liquified natural gas. The pressure regulator of the present invention is a robust, compact, high flow, low droop, low pressure drop and low creep regulator which is suitable for both OEM and aftermarket use. It can be used by itself, or with an optional third stage to provide a three stage regulator such as the atmospheric (or zero pressure differential) types commonly used to regulate the fuel pressure for gaseous carburetion systems. It is particularly useful in mono-, bi-, and dual fuel engine applications.