Patent ID: 10927719

Abstract:
A variable cam timing phaser arrangement is disclosed, comprising: a rotor having at least one vane; a stator co-axially surrounding the rotor, having a recess for receiving the vane of the rotor, wherein the vane divides the recess into a first chamber and a second chamber; and a control assembly for regulating hydraulic fluid flow from the first chamber to the second chamber or vice-versa. The control assembly comprises a central on/off piloted valve allowing or preventing fluid flow along a first unidirectional flow path between the first and second chambers, and a central solenoid valve allowing or preventing fluid flow along a second unidirectional flow path between the first and second chambers in the opposite direction to the first flow path. Also disclosed are an integrated valve unit for use in the variable cam timing phaser arrangement, and a method of controlling the timing of a camshaft.