The invention is characterized by a rotary vibration damper (4) which can be at least intermittently switched into or is permanently arranged in the drive power flow from a drive engine (1) to a variable-speed transmission (2) and which has at least one damper mass (5), the at least one damper mass being connected in a rotationally elastic manner to a component which is positioned in the drive power flow and which rotates about an axis of rotation, wherein the rotationally elastic connection is formed by at least one or precisely one leaf spring (7) which, in the stretched state, extends completely or at least partially in the radial direction to the axis of rotation and which bears the damper mass (5) on its radially outer end or in the region of its radially outer end.
