INTERNAL COMBUSTION ENGINE CAMSHAFT PHASESHIFT CONTROL SYSTEM

摘要

FMC 0143 PUS -25-89-363/89-364 A modular control mechanism for shifting the phase of a camshaft relative to a crankshaft in an internal combustion engine, accomplished by shifting the angular position of the camshaft relative to the crankshaft. The mechanism comprising two hydraulic cylindrical housings attached to either the camshaft flange or the camshaft driving sprocket, and plungers within the cylindrical housings attached to the other flange to form a rotational hydraulic coupling. The hydraulic cylinders providing a pair of cavities which vary in displacement as the two flanges are rotated relative to one another. A control apparatus regulating the flow of fluid between the hydraulic cylindrical housings, thus controlling the phase shift between the crankshaft and camshaft. The control device using the energy produced by the reaction torque pulses on the camshaft, and resultant pressure pulses in the cavities, thus creating a self-actuating system. The control apparatus consisting of one of three alternate means for precisely controlling the flow of fluid, thus allowing for a modulated selfactuating mechanism. One such preferred embodiment consisting of a pair of check valves which can be actuated through an axially adjustable helical cam lobe which is coupled to it.