Abstract: A valve operating device of an internal combustion engine, capable of varying the lift, the opening and closing angle of the intake valves. What makes it unique is that the camshaft is not fixed to the cylinder head, but it oscillates around a shaft, and by means of this oscillation, the valve lift and duration are changed. A command shaft changes the angular position of the camshaft holders and thus the camshaft position. The camshaft is driven by the crankshaft and rotates inside the camshaft holder. The cams drive intermediate arms. Rocker arms are driven by the intermediate arms and, in turn, drive the valves.