Abstract: A rotating fluid coupling of the type which has a primary coupling half and a secondary coupling half which together form a working chamber which is filled with working fluid. A control device which is arranged on the secondary coupling half is used to regulate the rotary take-off drive speed of the coupling by comparing an operating value, such as the centrifugal force which is a result of the rotating drive speed, with a variable command value and when the operating value differs from the command value initiates adjustment of the rotary drive speed. A fluid container on the secondary coupling half revolves with the secondary coupling half. A stationary supply line for control fluid to the fluid container is provided with a permanent outlet opening at a distance from the axis of rotation of the fluid coupling.