12 it can be seen that the camshaft torques have an approximately sinusoidal profile as a function of the rotational position of the camshaft at fixed angular positions in each case advance torques arise which alternate with retardation torques this is now utilized in a targeted manner for the adjustment of the camshaft in fig5 a switching position for the adjustment of the camshaft is schematically plotted such that the orifice cover 51 of the valve piston 27 is illustrated in a developed view in a plane the first cover part 51 a thus yields a rectangular profile with the inner edge pb and a straight outer edge bt illustrated opposite then is the second cover part 51 b with the inner edge pa and the outer edge at at the outer edge at the valve piston 27 is connected to the restoring spring 31 which presses the valve piston 27 against a magnet 21 not illustrated here also schematically illustrated are the first orifices 41 and the second orifices 43 as they are arranged relative to the orifice cover 51 corresponding to the axial position and rotational position of the valve housing 29 relative to the valve piston 27 the first orifices 41 correspond to a second chamber part b and the second orifices 43 correspond to a first chamber part a the chamber parts a b are divided by a vane 67 which forms an adjustment means 67 and which divides a pressure chamber 69 into the chamber parts a b.