Abstract: Apparatus for metering the quantity of air supplied to at least one fuel system in a carburetor for an internal combustion engine. The carburetor has at least one air passageway therein through which air is drawn into the engine. Fuel is supplied to the carburetor through the fuel system and mixed with air as it passes through the carburetor and the carburetor has a conduit through which air is introduced into the fuel system. The apparatus comprises a chamber having an air inlet in communication with the air passageway of the carburetor and a plurality of air outlets in communication with the conduit. An electrically operated valve selectively opens and closes each air outlet and electrical current is selectively supplied to each valve whereby one or more of the air outlets may be opened thereby to supply air from the passageway to the conduit and to control the quantity of air flowing to the fuel system.

Abstract: A combustible mixture of air and minute fuel droplets is produced for supply to the cylinders of an internal combustion engine. The engine includes a carburetor having a main air passageway in it, and an intake manifold interposed between the engine and the carburetor. The intake manifold includes at least one wall defining a plurality of fluid passageways operatively connected to the carburetor and to the combustion chambers of the engine. A throttle structure is mounted in the intake manifold. The combustible mixture is formed by introducing liquid fuel into a stream of intake air and uniformly distributing the fuel in the air by passing the air and fuel mixture through a constriction to increase the velocity of the mixture to sonic speed. The constriction occurs at the throttle structure in the manifold. The area of constriction and the amount of the fuel entering the air stream are adjustable for correlation with engine demand.

Abstract: An internal combustion engine is provided with an improved throttle structure. The engine includes a carburetor having an air passageway in it, and an intake manifold interposed between the engine and the carburetor, the carburetor being attached to the intake manifold by any convenient method. The intake manifold includes at least one wall defining a plurality of fluid passageways operatively connected to the carburetor and to the combustion chambers of the engine. In the preferred form of the invention, a cylindrical tube has an axial length chosen so that a first end of the tube extends into the carburetor while a second end extends into the intake manifold. The second end of the tube and the intake manifold define the throttle valve for the engine. The tube is mounted for movement between at least a first closed position where the second tube end is adjacent the wall of the manifold and a second open position where the second tube end is remote from the wall of the intake manifold.

Abstract: A combustible mixture of air and minute fuel droplets is produced for supply to the cylinders of an internal combustion engine. The engine includes a carburetor having a main air passageway in it, and an intake manifold interposed between the engine and the carburetor. The intake manifold includes at least one wall defining a plurality of fluid passageways operatively connected to the carburetor and to the combustion chambers of the engine. A throttle structure is mounted in the intake manifold. The combustible mixture is formed by introducing liquid fuel into a stream of intake air and uniformly distributing the fuel in the air by passing the air and fuel mixture through a constriction to increase the velocity of the mixture to sonic speed. The constriction occurs at the throttle structure in the manifold. The area of the constriction and the amount of fuel entering the air stream are adjustable for correlation with engine demand.

Abstract: A multiple stage carburetor has a linkage releasably connecting the secondary throttle for rotation with the primary throttle to open the second stage. A latch member for the linkage is movable between latched and unlatched positions and only when the latch member is in a latched position is the linkage connected for rotation of the secondary throttle. A diaphragm unit operated from a vacuum line to the intake manifold moves the latch member between latched and unlatched positions. A bimetallic element independent of the choke valve controls an air bleed to the vacuum line and is positioned to sense the normal operating temperature of the engine for movement of the latch member to latched position and subsequent opening of the second stage when such temperature is reached.

Abstract: A carburetor for an internal combustion engine has an idle or low speed system in which air is bled into the idle fuel passage. An air bleed valve member controls the amount of air flow through an air bleed port for the idle fuel passage and a diaphragm operated control is connected to the air bleed valve member to control the movement of the valve member. The diaphragm operated control has an air chamber on one side of the diaphragm and a vacuum chamber on the other side of the diaphragm with a restricted opening between the air and vacuum chambers. Upon a rapid engine deceleration to an idle position, the air bleed valve member is moved to a position to provide maximum air flow to the idle fuel passage for a limited period of time until the pressure is equalized between the vacuum chamber and the air chamber through the restricted opening.