Patent ID: 6997150

Claim:
A variable camshaft timing phaser for an internal combustion engine having at least one camshaft comprising: a housing having an outer circumference for accepting drive force; a rotor for connection to a camshaft coaxially located within the housing, the housing and the rotor defining at least one vane separating a chamber in the housing into an advance chamber and a retard chamber; a plurality of vanes in the chambers defined by the housing, wherein at least one CTA vane is cam torque actuated and at least one other OPA vane is oil pressure actuated; and a spool valve located along a rotational axis of the phaser and coupled to a source of oil pressure, the advance chamber and the retard chamber defined by the CTA vane and at least the advance chamber defined by the OPA vane, the spool valve having: an advanced position wherein fluid is routed from the retard chamber defined by the CTA vane to the advance chamber defined by the CTA vane and from a supply of oil to the advance chamber of the OPA vane; and a retard position wherein fluid is routed from the advance chamber defined by the CTA vane to the retard chamber defined by the CTA vane.