Patent ID: 7475661

Claim:
A camshaft phaser for controllably varying the phase relationship between a crankshaft and a camshaft in an internal combustion engine, comprising a differential bevel gear system having first and second bevel ring gears spaced apart along a first and common rotational axis, and having at least one spider bevel gear rotatable about a second axis orthogonal to said first axis and being meshed with said first and second bevel ring gears to transmit torque therebetween, wherein said second bevel ring gear is an output gear for driving said camshaft, further comprising: a) a sprocket mounted on said first bevel ring gear and drivable by said crankshaft; b) a control gear disposed in meshed relationship with said first and second bevel ring gears; and c) a rotary actuator attached to said control gear for controllably rotating said control gear to change the phase relationship between said first and second bevel ring gears.