Improvements in a variable valve timing system for an internal combustion engine

摘要

The invention relates to improvements in variable valve timing for an internal combustion engine. Specifically, the end design of a valve lifter or valve stem that provides a fine contact point with a variable profile cam that can enable its movement across the cam in order to provide a greater range of valve timing. In addition, the system provides a camshaft and camshaft journal system which allows for axial movement of a cam shaft on the basis of engine rpm and which allows for advancing or retarding a camshaft system on the basis of engine rpm.