Valve opening control device

Abstract

A valve opening control device for use with an internal combustion engine having cam-operated cylinder valves comprises a cam-like member having a cylindrical surface concentric with a shaft about which the member rotates and a cam-like section extending tangentially therefrom. The control device shaft is positioned parallel to and adjacent a rocker arm shaft or otherwise perpendicular to the axis of travel of the cylinder valve and/or the plane defined by such axis of travel and the plane of travel of a cylinder valve rocker arm for such valve. The valve opening control device transmits an opening force from the rotating engine camshaft for a distance which is progressively proportional to the distance the valve lifter travels in response to the rotating engine camshaft. The amount of rotational displacement of the control device is regulated by a hydraulic valve lifter, the effective length thereof being regulated by fluid pressure such that a higher fluid pressure increases the effective length thereof, causing the cylinder valve to be open through a larger degree of camshaft rotation and for a greater maximum distance. This fluid pressure is regulated indirectly by the relative position of the engine throttle, so that higher throttle settings increase the fluid pressure to the hydraulic valve lifter to cause the cylinder valve to be open a greater distance and for a longer period of time.