Abstract: In a variable phased valve lifter of an internal combustion engine, two or more roller lifter are allowed to move along constraining faces of a constraining mechanism in a first direction, and the constraining mechanism is allowed to move freely in a second direction. As the roller lifters move through their parallel arcuate paths, the engaging surface(s) of the roller lifters will engage with the constraining face(s) of the constraining mechanism, and each roller lifter will prevent the other from rotating about its longitudinal axis. The roller lifter is thus prevented from rotating about its longitudinal axis as it moves in arcuate fashion in cooperation with the constraining mechanism.

Abstract: In a variable phased valve lifter of an internal combustion engine, a roller lifter is allowed to move along a constraining face of a constraining mechanism in a first direction, and the constraining mechanism is allowed to move freely in a second direction. As the roller lifter moves through its arcuate path, the flat surface(s) of the roller lifter will slide across the constraining face(s) of the constraining mechanism, and end members of the constraining mechanism slide fore-and-aft in at least one stationary block. The roller lifter is thus prevented from rotating about its longitudinal axis as it moves in arcuate fashion in cooperation with the constraining mechanism.

Abstract: In a variable phased valve lifter of an internal combustion engine, a roller lifter is allowed to move along a constraining member of a constraining mechanism, and the constraining mechanism is allowed to move freely in a direction substantially parallel to a line perpendicular to the flat surface machined onto the roller lifter. As the roller lifter moves through its arcuate path, the parallel flat surface(s) of the roller lifter will slide across the constraining member(s) of the constraining mechanism, and end members of the constraining mechanism slide fore-and-aft within stationary blocks. The roller lifter is thus prevented from rotating about its longitudinal axis as it moves in arcuate fashion in cooperation with the constraining mechanism, maintaining line contact between the roller and cam lobe of the camshaft.

Abstract: In a variable phased valve lifter of an internal combustion engine, a roller lifter is allowed to move along a constraining member of a constraining mechanism, and the constraining mechanism is allowed to move freely in a direction substantially parallel to a line perpendicular to the flat surface machined onto the roller lifter. As the roller lifter moves through its arcuate path, the parallel flat surface(s) of the roller lifter will slide across the constraining member(s) of the constraining mechanism, and end members of the constraining mechanism slide fore-and-aft within stationary blocks. The roller lifter is thus prevented from rotating about its longitudinal axis as it moves in arcuate fashion in cooperation with the constraining mechanism, maintaining line contact between the roller and cam lobe of the camshaft.