Abstract

An infinitely variable cam indexer utilizes engine oil pressure to actuate a cam and preferably uses an inlet check valve in the oil source to minimize back flow during a torque reversal. The control system is in the center of the rotor and uses an electromechanical actuator, preferably a variable force solenoid, acting directly on the spool to control oil flow. This design reduces leakage and improves the response of the phaser. There are shorter oil passages as compared to a control system mounted at the cam bearing.