from that shown in fig1 and 2 in that the longitudinal axis 30 of the bolt 8 which is also the longitudinal axis of the transverse bore in the camshaft 2 which accommodates the bolt and of the bore 12 in the cam is not perpendicular to the axis 13 of the camshaft but instead is slightly oblique this slight angle makes it possible to eliminate the plug in the opening in the base circle 4a which is necessary to allow the seat 11 and the compartment 16 to be formed instead the circle 4a is eccentrically narrowed in one region by a recess 31 at one side to provide an opening for manufacture and for introducing the bolt 8 as the cam surface rotates it will actuate the tappet 6 as desired the bolt 8 illustrated in fig3 and 4 also has a slightly different design with respect to each of its positions and as to how it travels back and forth between them a chamber 32 which is sealed from the atmosphere and pressurized is located at the inner end of the bore 12 in the camshaft 2 which receives the bolt the chamber 32 communicates through longitudinal and transverse channels 33 and 34 in the bolt 8 with the axial hydraulic supply channel 14 in the camshaft 2 although the chamber 32 omits the spring which is included in the embodiment illustrated in fig1.