Abstract: The present invention is directed to open nozzle unit fuel injectors for injecting a metered quantity of fuel into the cylinder of an internal combustion engine, as synchronously controlled by a drive train, wherein the unit fuel injector comprises a body with an axial bore and a plunger assembly movable therein between a retracted position and an advanced position. The plunger includes a major diameter section, slidably movable in the axial bore to open and close a fuel supply orifice and a minor diameter section which extends in a bore of a cup portion of the injector body. The cup portion has an internal surface including plural diameter portions connected by an annular step.

Abstract: A unit fuel injector is disclosed to be used in a fuel injection system of an internal combustion engine wherein each unit injector is operated independently from one another and in synchronization with the internal combustion engine. Specifically, the unit injector in accordance with the present invention includes a reciprocating plunger assembly within the unit injector that controls fuel metering as well as fuel injection, and a valve device positioned between a minor diameter plunger section and a cup of the unit injector so as to permit fuel flow in one direction for fuel injection and to restrict flow of gases in the opposite direction. The valve device effectively reduces carbon build-up on the injector surfaces and increases injector longevity while reducing maintenance. Moreover, fuel metering is accurately controlled without substantial carboning flow losses.

Abstract: An improved, simplified pressure/time dependent fuel injector assembly for injecting fuel intermittently into a combustion chamber of an internal combustion engine. The injector assembly includes a unitary or single-piece injector body which has at least one groove-like channel on the exterior surface thereof. The channel is closed and sealed by a sleeve which is press-fit about that portion of the injector body on which the channel lies. For reciprocation within the injector body, there is provided an injector-plunger assembly which includes a top stop mechanism for adjustably setting the distance traveled by the plunger assembly during the reciprocatory movement thereof.

Abstract: A system is provided for controlling fuel flow within an internal combustion engine having a plurality of cylinders. The system includes a fuel source; a fuel pump responsive to the engine speed; and a multimode adjustable control valve connected to the fuel pump and a predetermined number of first cylinders. The control valve, when in a first mode, substantially shutting off fuel flow to the first cylinders, except for a minimal amount of fuel leakage from the valve to the first cylinders for lubricating purposes. When in a second mode, the control valve allows substantial fuel flow to the first cylinders. The control valve assumes its first mode when the operating temperature is below a predetermined amount and/or the engine is operating under a predetermined load.

Abstract: A diaphragm operated, air fuel control system for controlling the rate of fuel flow to an internal combustion engine in response to intake manifold pressure is disclosed wherein the transient response of the diaphragm operator is attenuated by a fuel filled control chamber. An attenuator assembly connected with the control chamber causes fuel to be supplied to the chamber at a rate which is greater than the rate at which fuel may be discharged from the control chamber. In one embodiment the chamber is formed on the side of the diaphragm operator which is opposite to the side to which intake manifold pressure is supplied. In another embodiment the control chamber is formed to receive one end of a plunger valve connected with the diaphragm operator.

Abstract: An air fuel ratio control for an I.C. engine fuel supply system is disclosed including a diaphragm operator for a fuel flow modulating valve responsive to engine intake manifold pressure as sensed through an air line connecting the diaphragm operator with the intake manifold and a drain line for returning to the engine fuel tank all fuel which may leak into the diaphragm operator due to seal rupture. The disclosed system further including a specially designed flow restrictor in the air line to prevent engine fuel tank pressurization and reverse fuel flow into the engine's intake manifold should the diaphragm operator rupture. The flow restrictor includes a control orifice which is sufficiently large to allow proper control by the diaphragm operator but yet not so large as to allow fuel tank pressurization should the diaphram rupture. In one embodiment the flow restrictor includes a check valve designed to close only upon improper fuel flow from the air fuel control to the intake manifold.