Abstract: In a fuel gas mixer 1 including a throttle valve 4 provided in an air intake passage 2 connected to an engine for opening and closing the air intake passage 2 and a fuel gas supply passage 6 connected to the air intake passage 2 upstream of the throttle valve 4. A fuel gas control valve 5 is provided in the air intake passage 2 upstream of the connecting part of the fuel gas supply passage 6 for opening and closing the air intake passage 2, and a fuel gas control value controlling means 11 is provided for varying the degree of the opening of the fuel gas control value 5 depending upon the operating state of the engine.

Abstract: In a fuel gas mixer 1 comprising a throttle valve 4 provided in an air intake passage 2 connected to an engine for opening and closing the air intake passage 2 and a fuel gas supply passage 6 connected to the air intake passage 2 upstream of the throttle valve 4. A fuel gas control valve 5 is provided in the air intake passage 2 upstream of the connecting part of the fuel gas supply passage 6 for opening and closing the air intake passage 2, and a fuel gas control valve controlling means 11 is provided for varying the degree of the opening of the fuel gas control valve 5 depending upon the operating state of the engine.

Abstract: A fuel control system for an engine, and particularly one that employs a gaseous fuel and which controls the air-fuel ratio by a feedback control system. The feedback control system is adjusted by a corrective factor that is determined by engine running conditions so as to obtain better control over the desired fuel-air mixture.

Abstract: A gaseous fueled engine and method for controlling the gaseous fuel supply using a feedback control to maintain a stoichiometric mixture under all normal running conditions. The feedback control is discontinued under certain running conditions and control is provided in another method so as to accommodate situations such as starting, conditions when the catalyst associated with the engine is overheated, conditions when the engine is running at wide open throttle to avoid the possibility of catalyst overheating and conditions of rapid deceleration so as to reduce the fuel supply and avoid overly rich exhaust gases when the engine is operating as a pump under extreme deceleration.

Abstract: A feedback control system for a gaseous fuel supplied internal combustion engine wherein the air-fuel ratio is maintained at a stoichiometric ratio by mixing air with the gaseous fuel supply to the charge former. A manually controlled air bleed is incorporated to permit adjustment for deterioration in the system due to age or carbon deposits or the like. In addition, the feedback control position of the air bleed valve is memorized, and the memorized value is utilized for control under some conditions when feedback control would not be appropriate, such as for cold starting when the sensor is not at its operating temperature or upon the resumption of normal control after a fuel shutoff during decell.

Abstract: Several embodiments of engines and systems for fueling engines to reduce the emission of unwanted exhaust gas constituents and to improve the fuel economy of the engine. A catalytic converter is provided in the exhaust system and a gaseous fuel is used at least during starting so as to bring the catalytic converter up to its operating temperature rapidly without necessitating the provision of an enriched fuel/air mixture. An oxygen sensor is employed in the exhaust system and a feedback control system varies the fuel/air ratio of the engine during its running in response to the output of the oxygen sensor. In order to test that the oxygen sensor is at its operating condition before feedback control is initiated, a rich fuel mixture is supplied and this rich fuel mixture is discontinued immediately upon the receipt of a signal from the oxygen sensor indicating that a rich mixture exits. Applications of the principal to both air valve type of carburetors and conventional carburetors are disclosed.

Abstract: Several embodiments of engines and systems for fueling engines to reduce the emission of unwanted exhaust gas constituents and to improve the fuel economy of the engine. A catalytic converter is provided in the exhaust system and a gaseous fuel is used at least during starting so as to bring the catalytic converter up to its operating temperature rapidly without necessitating the provision of an enriched fuel/air mixture. An oxygen sensor is employed in the exhaust system and a feedback control system varies the fuel/air ratio of the engine during its running in response to the output of the oxygen sensor. In order to test that the oxygen sensor is at its operating condition before feedback control is initiated, a rich fuel mixture is supplied and this rich fuel mixture is discontinued immediately upon the receipt of a signal from the oxygen sensor indicating that a rich mixture exits. Applications of the principal to both air valve type of carburetors and conventional carburetors are disclosed.

Abstract: Two embodiments of air/fuel ratio adjusting systems for gaseous-fueled internal combustion engines. In each embodiment, a pressure regulator supplies regulated fuel in gaseous form from a source in which it is stored in a liquid form to a charge former that has a fuel control device such as a needle valve. The air/fuel ratio is maintained constant by mixing atmospheric air with the fuel before the charge former fuel control device under the control of an oxygen sensor in the exhaust system. In one embodiment, an enrichment system is also incorporated for supplying enrichment fuel under acceleration or cold starting conditions.