Device combustion engine

Abstract

A device for controlling valve movements in an internal combustion engine includes a rotating camshaft having a cam curve, the camshaft being designed, via a rocker arm, to interact with a valve mechanism for operating the inlet or exhaust valve by a valve spring. The valve mechanism includes timing gear which allows the return movement of the valve mechanism to be controlled during the closing phase of the inlet valve or exhaust valve, independently of the cam curve. A resilient element is arranged between the rocker arm and a fixed point in such a way that the rocker arm continuously follows the cam curve as the camshaft rotates. The force of the valve spring is adjusted to the moving mass of the valve mechanism and to forces counteracting the valve closure. The force exerted by the resilient element are adjusted to the mass of the rocker arm for the purpose of minimizing the energy losses of the valve mechanism. Respective central contact points between the rocker arm shaft and the rocker arm during the period when the rocker arm and the valve mechanism are separated or not separated are displaced in relation to one another in order to ensure lubrication of the rocker arm shaft.