Patent ID: 8800515

Claim:
A variable camshaft timing phaser for an internal combustion engine comprising: a housing assembly having an outer circumference for accepting drive force; a rotor assembly coaxially located within the housing for connection to a camshaft, the housing assembly and the rotor assembly defining at least two vanes separating chambers in the housing assembly into advance chambers and retard chambers, wherein at least one of the two vanes is cam torque actuated and defines a cam torque actuated advance chamber and a cam torque actuated retard chamber, and at least an other of the at least two vanes is oil pressure actuated and defines an oil pressure actuated retard chamber and an oil pressure actuated advance chamber; a supply line coupled to a fluid input; at least one exhaust line; a control valve movable between an advance mode, a retard mode, and a holding position, for directing fluid between the cam torque actuated retard chamber and the cam torque actuated advance chamber through an advance line, a common line with a retard check valve and an advance check valve, and a retard line; wherein when the control valve is in the advance mode, fluid is routed from the cam torque retard chamber to the cam torque advance chamber through the advance check valve, and fluid to the cam torque advance chamber is additionally routed to the oil pressure actuated advance chamber and fluid from the oil pressure retard chamber is routed to the at least one exhaust line; wherein when the control valve is in the retard mode, fluid is routed from the cam torque advance chamber to the cam torque retard chamber through the retard check valve, and fluid to the cam torque retard chamber is additionally routed to the oil pressure actuated retard chamber and fluid from the oil pressure advance chamber is routed to the at least one exhaust line; and wherein when the control valve is in the holding position, fluid is blocked from moving between the cam torque actuated advance chamber and the cam torque actuated retard chamber, maintaining the oil pressure actuated vane and the cam torque actuated vane in position through oil pressure.