Patent ID: 6990938
Filing Date: 2006-01-31
Classification: F01L

Abstract:
1. A valve operating device for an internal combustion engine, including an intake-side cam follower for contacting an intake valve to open and close the intake valve, an exhaust-side cam follower for contacting an exhaust valve to open and close the exhaust valve, and an intake-side characteristic adjustment mechanism and an exhaust-side characteristic adjustment mechanism for respectively adjusting characteristics of the intake valve and the exhaust valve, wherein each of the characteristic adjustment mechanisms comprises: a cam shaft that rotates together with rotation of a crankshaft of the internal combustion engine; a control cam that rotates together with the cam shaft; a holder rotatably supported on the cam shaft; a driving device that causes the holder to oscillate around the cam shaft; a rocker lever rotatably supported on the holder to be oscillated by the control cam; and a drive cam that is caused to rotate around the cam shaft by oscillation of the holder transmitted via the rocker lever and by oscillation of the rocker lever, to drive the intake-side cam follower or the exhaust-side cam follower; wherein the driving device of each of the intake-side characteristic adjustment mechanism and the exhaust-side characteristic adjustment mechanism is configured to cause the associated holder to oscillate in such a manner that a valve open timing of the intake valve is retarded as a maximum lift amount of the intake valve becomes smaller and the valve close timing of the exhaust valve is advanced as a maximum lift amount of the exhaust valve becomes smaller.