Patent ID: 6382149
Filing Date: 2002-05-07
Classification: F01L

Abstract:
Valve timing gear for an internal-combustion engine,comprising a timing cam of a camshaft acting by a tilting segment in a tappet in a timing manner upon a lifting valve, the tilting segment being constructed with a contact path acted upon by the timing cam and arranged in a movably guided manner by a circular-arc section concentric to the axis of rotation of the camshaft in the tappet such that, by a control device, during each valve lift, an engagement of the contact path with flanks of the rotating timing cam determining an opening and closing phase of the lifting valve and being achieved by a swivelling movement of the tilting segment which is forcibly controlled in the same direction and/or in the opposite direction relative to the rotating direction of the timing cam, wherein the control device comprises a slider rocker which is guided in the valve lifting direction by way of a first sliding hinge joint arranged on the engine section side and another sliding hinge joint provided on the tilting segment side, and which has a control opening which is penetrated with clearance by a timing-cam-free section of the camshaft, and an element, which can be operated in a controlled manner, of an adjusting device being arranged in/on the camshaft while rotating with the camshaft, is applied to the circumference of the control opening such that the slider rocker being adjustable in the valve lifting direction by the control opening eccentrically to the axis of rotation of the camshaft, while the camshaft is rotating, carries out for each valve lift a periodic rocking movement which forcibly controls the tilting segment and takes place transversely to the valve lifting direction with a superimposition with a sliding movement caused in the valve lifting direction.