Abstract

A phaser for maintaining an angular relationship between a crank shaft and a cam shaft or among more than one cam shafts is provided. The phaser includes a rotor having a plurality of vanes integral to the rotor and protruding from the rotor body. The plurality of vanes is disposed to oscillate within their respective chambers formed by the rotor and a housing, thereby maintaining the angular relationship. The phaser also includes a shoulder integral to the rotor and interposed between one of the pluralities of vanes and the rotor body, thereby ensuring that the rotor face is always covering a locking pin hole regardless of vane position. The phaser further includes an inlet check valve located within the phaser structure or in very close proximity to the phaser, thereby reducing control fluid leakage.