Abstract: In a valve operating control device hysteresis brake particularly for a valve drive of an internal combustion engine, including a hysteresis device rotatable about an axis of rotation so as to be movable along a pole structure of an electromagnet forming a magnetic field effect region in the hysteresis device along the pole structure, a compact and high-performance arrangement is provided for the hysteresis device by an offset in the axial and/or radial direction providing at least two magnetic field effect regions in which the hysteresis device is movably supported.

Abstract: In an adjusting device for a camshaft of an internal combustion engine having a drive element which is driven by a crankshaft of the internal combustion engine, an output element which drives the camshaft of the internal combustion engine, and an actuating element controlled by a brake so as to provide for a relative rotation between the drive element and output element by varying the braking torque effective on the actuating element.