Emission control valve for gas-fueled engines

摘要

An emission control device for use with stationary or mobile gas-fueled internal combustion engines is described, which is placed in the fuel supply line and operates with full fuel authority. An oxygen sensor measures exhaust oxygen content. The valve internally houses a programmable microprocessor, a pressure transducer and a fuel flow conduit throttled by a balanced poppet valve. Signals to the microprocessor from the oxygen sensor, the pressure transducer indicating outflow gas pressure cause the microprocessor to motivate an actuator to move the valve within the gas stream and thus regulate the outlet pressure and also the gas flow rate to maintain a desired air/fuel ratio to the engine and keep exhaust emissions at an optimum level consistent with the engine operating load requirements and characteristics. Finite incremental control of valve position, preferably assisted by an internal position transducer, permits close control of the exhaust emissions.