Abstract: An air-vent system for a carburetor which selectively opens an outer vent of a float chamber to a fuel vapour adsorptive vessel under the control of a control valve which is normally opened by a spring force and is closed by air pressure delivered from an air pump driven by an engine when the engine rotational speed increases beyond a predetermined level.

Abstract: Flow regulating apparatus comprises a turbulent-flow valve with a fluid supply connected at the upstream side thereof. A fixed pressure bias is applied to the fluid upstream of the valve whereby the mass flow rate of fluid through the valve is directly proportional to the pressure differential across the apparatus when these variations are within a selected pressure range. Such flow regulation may be used in a system for introducing a metered amount of liquid fuel into an air stream to provide a combustible air-fuel mixture having a substantially constant air-to-fuel ratio. With this system air is passed through a constricted zone to increase its velocity to sonic, and the area of the constricted zone is varied in correlation with operating demands imposed upon the engine for which the mixture is produced.

Abstract: To provide a carburetor in which the fuel/air proportion in the mixture is maintained substantially constant despite variations in atmospheric pressure, supplementary air is supplied to the induction passage downstream of the throttle valve, in a fixed choke carburetor, or to the mixing chamber in an air valve carburetor, the supply of such supplementary air being controlled in accordance with atmospheric pressure.

Abstract: A fuel-metering system adapted for attachment to an air-intake suction tube, having a throttle passage therein, of an internal combustion engine having an exhaust for waste gases, which system comprises:A. a fuel reservoir having an airspace above the fuel therein,B. structure for measuring the air pressures in the airspace and the suction tube and for metering fuel amounts to be introduced into given amounts of air flowing through the suction tube, in dependence on the air pressures, andC.

Abstract: In a carburetor having an induction passage, a variable venturi in the induction passage, a fuel bowl and means for metering fuel flow from the fuel bowl to the induction passage, the method of compensating for changes in barometric pressure due to either atmospheric or altitude changes is disclosed as applying a vacuum or reduced pressure to the interior of the fuel bowl thereby reducing the fuel pressure which would otherwise exist, and causing a corresponding reduction in the mass rate of fuel flow in relation to the volume rate of air flow generally in accordance with a reduction in ambient pressure.

Abstract: A carburetor provided with a rocking member which will be able to forcibly move a needle valve to a valve closing position through a float when a carburetor body inclines by an angle larger than a predetermined angle from a normal position, in order to prevent the overflow of a fuel caused by continuously flowing into the float chamber from a fuel tank when the carburetor body inclines extremely.

Abstract: A carburetor for minimizing the variation in the ratio of fuel contained in the fuel-air mixture due to fuel evaporation within the float chamber. The carburetor has an air passage providing communication between the float chamber and the air intake pipe at a location upstream of the throttle valve. A further air passage provides communication between the float chamber and the air intake pipe at a location disposed downstream of the throttle valve, which further air passage contains a throttle therein for controlling the flow therethrough.

Abstract: A carburetor has a small air passage connected to the main induction passage by a sonic flow orifice; the small passage being supplied with compressed air at all times at a pressure and volume maintaining sonic flow; a fuel supply line is connected to the orifice for a constant flow of fuel, the rate of flow being varied as a function both of throttle valve position and manifold vacuum level.

Abstract: A float chamber is in communication with the surrounding atmosphere through a valve actuatable in response to a negative pressure in an intake manifold so that when an engine is excessively inclined or upset the valve is closed under the pressure of the fuel in the float chamber. Therefore, the overflow of the fuel into the carburetor barrel may be prevented and a fire in the vehicle avoided.