Patent ID: 8893677

Claim:
A variable cam timing system including a phaser for an internal combustion engine including a housing assembly with an outer circumference for accepting drive force and a rotor assembly coaxially located within the housing for connection to a camshaft, having a plurality of vanes, wherein the housing assembly and the rotor assembly define at least one chamber separated by a vane into an advance chamber with an advance wall and a retard chamber with a retard wall, the vane within the chamber acting to shift relative angular position of the housing assembly and the rotor assembly when fluid is supplied to the advance chamber or the retard chamber, the system comprising: a control valve for directing fluid from a fluid input to and from the advance chamber and the retard chamber through an advance line, a retard line, a supply line coupled to the fluid input, and at least one exhaust line, and the control valve being movable between a detent mode and an oil pressure actuated mode comprising: an advance mode in which fluid is routed from the fluid input to the advance chamber and fluid is routed from the retard chamber to the exhaust lines, a retard mode in which fluid is routed from the fluid input to the retard chamber and fluid is routed from the advance chamber to the exhaust lines, a holding position in which fluid is routed to the advance chamber and the retard chamber and a retard locking mode in which the vane is adjacent to the advance wall; a first lock pin slidably located in the rotor assembly, the first lock pin being moveable within the rotor assembly from a locked position in which an end portion of the first lock pin engages a first recess of the housing assembly, to an unlocked position in which the end portion does not engage the first recess of the housing assembly, the first recess in fluid communication with the supply line; and a second lock pin slidably located in the rotor assembly, the second lock pin being moveable within the rotor assembly from a locked position in which an end portion of the second lock pin engages a second recess of the housing assembly, to an unlocked position in which the end portion does not engage the second recess of the housing assembly, the second recess in fluid communication with the advance chamber; wherein when the control valve is in the retard locking mode, fluid to the second recess flows to the advance chamber and the second lock pin engages the second recess of the housing assembly, locking the relative angular position of the housing assembly and the rotor assembly; and wherein when the control valve is in the detent mode, the control valve blocks the at least one exhaust line, retaining fluid within the advance chamber and retard chamber and blocks the supply line to the first recess, such that the first lock pin engages the first recess of the housing assembly, locking the relative angular position of the housing assembly and the rotor assembly.