Apparatus and method for controlling valve movements in an internal
combustion engine that has at least one inlet valve (12) and at least one
exhaust valve for controlling the connection between the combustion
chamber in the cylinder and an inlet system and an exhaust system
respectively. A rotatable camshaft is provided that has a cam curve
including a rising ramp (10a) and a falling ramp (10b) that is designed
to interact with a valve mechanism (14) for actuation of the inlet or
exhaust valve (12) under the action of a valve spring (13). The valve
mechanism (14) includes control members (21, 22, 23, 24, 25 and 26) that
allow return movement of the valve mechanism to be controlled during the
closing phase of the inlet valve (12) or the exhaust valve, independently
of the falling ramp (10b) of the cam curve. The control members (21, 22,
23, 24, 25 and 26) are arranged so that the closing of the valve can be
delayed for an adjustable period of time by means of a hydraulically
adjustable force counteracting the closing force of the valve spring.