Camshaft phase

A method for operating a camshaft phaser for use with an internal combustion engine for controllably varying the phase relationship between a crankshaft and a camshaft in said internal combustion engine, said camshaft phaser comprising a stator having a plurality of lobes and connectable to said crankshaft of said internal combustion engine to provide a fixed ratio of rotation between said stator and said crankshaft;

• a rotor coaxially disposed within said stator, said rotor having a plurality of vanes interspersed with said lobes defining alternating advance chambers and retard chambers, wherein said advance chambers receive pressurized oil in order to change the phase relationship between said crankshaft and said camshaft in an advance direction and said retard chambers receive said pressurized oil in order to change the phase relationship between said camshaft and said crankshaft in a retard direction;
• and a lock pin disposed within one of said rotor and said stator for selective engagement with a lock pin seat for preventing a change in phase relationship between said rotor and said stator at a predetermined aligned position of said rotor relative to said stator;
• and a lock pin oil control valve within said camshaft phaser for 1) selectively directing said pressurized oil to said lock pin for disengaging said lock pin from said lock pin seat, 2) selectively directing said pressurized oil to said lock pin for disengaging said lock pin from said lock pin, and 3) venting said pressurized oil from said lock pin for engaging said lock pin with said lock pin seat, said method comprising:
• selectively supplying said pressurized oil to said lock pin oil control valve from one of said advance chambers;
• and
• selectively supplying said pressurized oil to said lock pin oil control valve from one of said retard chambers.