A controllable filling fluid coupling has outlets at the radially outer part of its working circuit periphery for the removal of a cooling flow of working liquid fed into the working circuit when the input is shut down and the output is rotated by the load which is driven from another source of power. The outlets have collecting scoops which face into the vortex which is set up under these conditions. Under normal driving conditions, the liquid in the vortex travels in the opposite direction, i.e. from the input member to the output member at the outer periphery and is not intercepted by the collecting scoops.