VARIABLE VALVE DRIVE WITH A ROCKER ARM

The invention relates to a variable valve train for a lift valve, in particular for a charge exchange valve of an internal combustion engine, which can be periodically moved between a closed and an open position indirectly by a cam via a rocker arm. The variable valve train (1) comprises a camshaft (3) having at least one first cam (3) and at least one second cam (4, 5) arranged offset in the longitudinal direction of the camshaft (3), wherein the at least one first cam (3) and the at least one second cam (4, 5) are designed differently in their cam contour. The valve train (1) further comprises a rocker arm (10) pivotably supported about a rocker arm axis (2), which is assigned to the at least one first cam (3) at its camshaft-side end (11) via a pressure roller (13) and is in operative connection with at least one lift valve at its valve-side end (12), as well as a roller lever (20) which is assigned to the at least one second cam (4, 5) at its camshaft-side end (21) and is pivotably hinged to the rocker arm (10) about the rocker arm axis (2) at its other end. The variable valve train (1) further comprises a switchable hydraulic locking device (30), by means of which the rocker arm (10) and the roller lever (20) are rigidly locked together upon activation or deactivation and both follow the movement of the at least one second cam (4, 5).