Variable cam phaser for internal combustion engine.

摘要

A variable cam phaser (VCP) (18) is disclosed in various modifications. The VCP includes a piston (70) responsive to pressure in a fluid chamber (76) having an inlet orifice (130) and a plurality of outlets including a first outlet (146) and a plurality of second outlets (148, 150, 152). A valve slide (136) is movable to cover said second outlets one after another to pressurize the fluid chamber to displace the piston against a return spring (80). Outer and inner splined slides (56, 58) are drivingly mated with an internal helical spline (40) of a cylindrical body (3) secured to a sprocket (20) and an external helical spline (46) of a stub shaft (42) secured to a camshaft (12). The splined slides (56, 58) are disposed between the piston (70) and the return spring (80). Thus, movement of the piston and splined slides assembly in response to pressurization or depressurization of the fluid chamber advances or retards the valve timing or phase angle of the camshaft rel;ative to the sprocket (20).