Abstract: A camshaft phaser includes a stator having a plurality of lobes and a rotor coaxially disposed within the stator and having a plurality of vanes interspersed with the lobes defining a plurality of alternating advance chambers and retard chambers such that a phasing valve supplies and vents oil to and from the advance and retard chambers. A first check valve allows oil to flow from only one of the retard chambers to only one of the advance chambers when a first diverter valve permits communication between the one of the advance chambers and the first check valve and a second check valve allows oil to flow from the one of the advance chambers to the one of the retard chambers when a second diverter valve permits communication between the one of the retard chambers and the second check valve.

Abstract: A camshaft phaser includes a stator; a rotor defining an advance chamber and a retard chamber with the stator; a valve spool that is rotatable about an axis and defining a supply chamber and a vent chamber with the rotor; an actuator which rotates the valve spool to change the position of the rotor relative to the stator by 1) supplying oil from the supply chamber to the advance chamber and venting oil from the retard chamber to the vent chamber and 2) supplying oil from the supply chamber to the retard chamber and venting oil from the advance chamber to the vent chamber; and a check valve which is displaceable axially between an open position which allows oil to flow from the vent chamber to the supply chamber and a closed position which prevents oil from flowing from the supply chamber to the vent chamber.

Abstract: A camshaft phaser includes an input member; an output member defining an advance chamber and a retard chamber with the input member; a valve spool moveable between an advance position and a retard position and having a valve spool bore with a phasing volume and a venting volume defined therein such that the phasing volume is fluidly segregated from the venting volume; and a phasing check valve within the valve spool. The advance position allows oil to flow through the phasing check valve and through the phasing volume from the advance chamber to the retard chamber while preventing oil from flowing from the retard chamber to the advance chamber and the retard position allows oil to flow through the check valve and through the phasing volume from the retard chamber to the advance chamber while preventing oil from flowing from the advance chamber to the retard chamber.

Abstract: A camshaft phaser includes an input member; an output member defining an advance chamber and a retard chamber with the input member; a valve spool moveable between an advance position and a retard position. The valve spool has a phasing volume and a venting volume defined therein such that the phasing volume is fluidly segregated from the venting volume. The valve spool also has a passage providing fluid communication between the phasing volume and the exterior of the valve spool. Oil is supplied to the advance chamber from the phasing volume through the passage in order to retard the timing of a camshaft and oil is supplied to the retard chamber from the phasing volume through the passage in order to advance the timing of the camshaft.

Abstract: A camshaft phaser includes a stator; a rotor defining an advance chamber and a retard chamber with the stator; a valve spool that is rotatable about an axis and defining a supply chamber and a vent chamber with the rotor; an actuator which rotates the valve spool to change the position of the rotor relative to the stator by 1) supplying oil from the supply chamber to the advance chamber and venting oil from the retard chamber to the vent chamber and 2) supplying oil from the supply chamber to the retard chamber and venting oil from the advance chamber to the vent chamber; and a check valve which is displaceable axially between an open position which allows oil to flow from the vent chamber to the supply chamber and a closed position which prevents oil from flowing from the supply chamber to the vent chamber.

Abstract: A camshaft phaser includes an input member; an output member defining an advance chamber and a retard chamber with the input member; a valve spool coaxially disposed within the output member such that the valve spool is rotatable relative to the output member and the input member, the valve spool defining a supply chamber and a vent chamber with the output member; an actuator which rotates the valve spool in order to change the position of the output member relative to the input member by supplying pressurized oil from the supply chamber to one of the advance chamber and the retard chamber and venting oil to the vent chamber from the other of the supply chamber and the advance chamber; and a check valve which allows oil to flow from the vent chamber to the supply chamber and prevents oil from flowing from the supply chamber to the vent chamber.

Abstract: A camshaft phaser includes an input member; an output member defining an advance chamber and a retard chamber with the input member; a valve spool coaxially disposed within the output member such that the valve spool is rotatable relative to the output member and the input member, the valve spool defining a supply chamber and a vent chamber with the output member; an actuator which rotates the valve spool in order to change the position of the output member relative to the input member by supplying pressurized oil from the supply chamber to one of the advance chamber and the retard chamber and venting oil to the vent chamber from the other of the supply chamber and the advance chamber; and a check valve which allows oil to flow from the vent chamber to the supply chamber and prevents oil from flowing from the supply chamber to the vent chamber.

Abstract: A camshaft phaser includes an input member; an output member defining an advance chamber and a retard chamber with the input member; a valve spool moveable between an advance position and a retard position. The valve spool has a phasing volume and a venting volume defined therein such that the phasing volume is fluidly segregated from the venting volume. The valve spool also has a passage providing fluid communication between the phasing volume and the exterior of the valve spool. Oil is supplied to the advance chamber from the phasing volume through the passage in order to retard the timing of a camshaft and oil is supplied to the retard chamber from the phasing volume through the passage in order to advance the timing of the camshaft.

Abstract: A camshaft phaser includes an input member; an output member defining an advance chamber and a retard chamber with the input member; a valve spool moveable between an advance position and a retard position and having a valve spool bore with a phasing volume and a venting volume defined therein such that the phasing volume is fluidly segregated from the venting volume; and a phasing check valve within the valve spool. The advance position allows oil to flow through the phasing check valve and through the phasing volume from the advance chamber to the retard chamber while preventing oil from flowing from the retard chamber to the advance chamber and the retard position allows oil to flow through the check valve and through the phasing volume from the retard chamber to the advance chamber while preventing oil from flowing from the advance chamber to the retard chamber.

Abstract: A camshaft phaser includes a stator having a plurality of lobes and a rotor coaxially disposed within the stator and having a plurality of vanes interspersed with the lobes defining a plurality of alternating advance chambers and retard chambers such that a phasing valve supplies and vents oil to and from the advance and retard chambers. A first check valve allows oil to flow from only one of the retard chambers to only one of the advance chambers when a first diverter valve permits communication between the one of the advance chambers and the first check valve and a second check valve allows oil to flow from the one of the advance chambers to the one of the retard chambers when a second diverter valve permits communication between the one of the retard chambers and the second check valve.

Abstract: A camshaft phaser is provided for varying the phase relationship between a crankshaft and a camshaft in an engine. The camshaft phaser includes a stator having lobes. A rotor is disposed within the stator includes vanes interspersed with the stator lobes to define alternating advance and retard chambers. A lock pin is provided for selective engagement with a lock pin seat for preventing relative rotation between the rotor and the stator. Pressurized oil disengages the lock pin from the seat while oil is vented for engaging the lock pin with the seat. A phase relationship control valve is coaxial with the rotor and controls the flow of oil into and out of the chambers. A lock pin control valve is coaxial with the phase relationship control valve and controls the flow of oil to and from the lock pin. The control valves are operational independent of each other.

Abstract: A camshaft phaser for controllably varying the phase relationship between a crankshaft and a camshaft in an internal combustion engine includes stator having a plurality of lobes. A rotor is coaxially disposed within the stator and has a plurality of vanes interspersed with the lobes defining alternating advance chambers and retard chambers. A lock pin is disposed within the rotor for selective engagement with a lock pin seat for preventing a change in phase relationship between the rotor and the stator. A lock pin oil control valve is located within the camshaft phaser for 1) selectively receiving the pressurized oil from one of the advance chambers and directing the pressurized oil to the lock pin and 2) selectively receiving the pressurized oil from one of the retard chambers and directing the pressurized oil to the lock pin for disengaging the lock pin from the lock pin.

Abstract: A camshaft phaser for controllably varying the phase relationship between a crankshaft and a camshaft in an internal combustion engine includes stator having a plurality of lobes. A rotor is coaxially disposed within the stator and has a plurality of vanes interspersed with the lobes defining alternating advance chambers and retard chambers. A lock pin is disposed within the rotor for selective engagement with a lock pin seat for preventing a change in phase relationship between the rotor and the stator. A lock pin oil control valve is located within the camshaft phaser for 1) selectively receiving the pressurized oil from one of the advance chambers and directing the pressurized oil to the lock pin and 2) selectively receiving the pressurized oil from one of the retard chambers and directing the pressurized oil to the lock pin for disengaging the lock pin from the lock pin.

Abstract: A camshaft phaser is provided for varying the phase relationship between a crankshaft and a camshaft in an engine. The camshaft phaser includes a stator having lobes. A rotor disposed within the stator and rotatable between a full retard position to a full retard position includes vanes interspersed with the stator lobes to define alternating advance and retard chambers. A lock pin selectively engages a lock pin seat for preventing a change in phase relationship between the rotor and the stator at a predetermined aligned position between the full advance and full retard positions. A counterbalancing member is located within one of the advance chambers or the retard chambers, attached to a vane to thereby apply a torque between the rotor and the stator only when the rotor is between the predetermined aligned position and one of the full retard position and the full advance position.

Abstract: A camshaft phaser for controllably varying the phase relationship between a crankshaft and a camshaft in an internal combustion engine is attached to the camshaft with a camshaft phaser attachment bolt. The camshaft phaser attachment bolt includes a stepped bore for communicating pressurized oil from the internal combustion engine to a valve spool and is defined by a larger diameter bore, a smaller diameter bore, and a shoulder between the larger diameter bore and the smaller diameter bore. A check valve assembly includes a check valve body axially moveable within the larger diameter bore. The check valve body includes a plurality of azimuthally spaced guiding walls, a plurality of clearance walls separating the guiding walls, and a seating surface at one end of the guiding walls and the clearance walls for selectively seating with the shoulder to prevent fluid communication between the larger diameter bore and the smaller diameter bore.

Abstract: A camshaft phaser includes a stator having lobes and a rotor disposed within the stator having vanes interspersed with the lobes. A lock pin disposed within one of the rotor and the stator selectively engages a seat for preventing relative rotation between the rotor and the stator when the lock pin is engaged with the seat. A bolt extends coaxially through the rotor and the stator to attach the camshaft phaser to a camshaft. A valve spool in the bolt controls the flow of oil to and from the lock pin. The bolt includes a supply drilling extending therethrough to supply pressurized oil to the valve spool.

Abstract: A camshaft phaser is provided for varying the phase relationship between a crankshaft and a camshaft in an engine. The camshaft phaser includes a stator having lobes. A rotor is disposed within the stator includes vanes interspersed with the stator lobes to define alternating advance and retard chambers. A lock pin is provided for selective engagement with a lock pin seat for preventing relative rotation between the rotor and the stator. Pressurized oil disengages the lock pin from the seat while oil is vented for engaging the lock pin with the seat. A phase relationship control valve is coaxial with the rotor and controls the flow of oil into and out of the chambers. A lock pin control valve is coaxial with the phase relationship control valve and controls the flow of oil to and from the lock pin. The control valves are operational independent of each other.

Abstract: A camshaft phaser is provided for varying the phase relationship between a crankshaft and a camshaft in an engine. The camshaft phaser includes a stator having lobes. A rotor is disposed within the stator includes vanes interspersed with the stator lobes to define alternating advance and retard chambers. A lock pin is provided for selective engagement with a lock pin seat for preventing relative rotation between the rotor and the stator. Pressurized oil disengages the lock pin from the seat while oil is vented for engaging the lock pin with the seat. A phase relationship control valve is coaxial with the rotor and controls the flow of oil into and out of the chambers. A lock pin control valve is coaxial with the phase relationship control valve and controls the flow of oil to and from the lock pin. The control valves are operational independent of each other.

Abstract: A camshaft phaser is provided for varying the phase relationship between a crankshaft and a camshaft in an engine. The camshaft phaser includes a stator having lobes. A rotor disposed within the stator includes vanes interspersed with the stator lobes to define alternating advance and retard chambers. A lock pin is provided for selective engagement with a lock pin seat for preventing relative rotation between the rotor and stator. Pressurized oil disengages the lock pin from the seat while oil is vented for engaging the lock pin with the seat. A phase relationship control valve is located coaxially within the rotor to control the flow of oil into and out of the chambers. A lock pin oil passage communicates oil to and from the lock pin based on input from a lock pin control valve located outside of the camshaft phaser. The control valves are operational independent of each other.

Abstract: A camshaft phaser attachment system is provided for attaching a camshaft phaser to a camshaft of an internal combustion engine. The camshaft phaser attachment system includes a camshaft phaser for controllably varying the phase relationship between a crankshaft and the camshaft. The camshaft phaser attachment system also includes a camshaft phaser installation tool having a handle with a head sized to be inserted through an opening of a cover of the camshaft phaser. A plurality of notches formed on a rotor of the camshaft phaser interfit with a plurality of tangs of the head. The head includes a recess on the periphery to provide clearance relative to a bias spring capture flange extending radially inward from the opening. The head also includes a central passage extending through the head to allow a tightening tool to tighten a bolt used to hold the camshaft phaser to the camshaft.