The invention concerns a centrifugal positive blocking brake for shutter drives. The brake includes centrifugal blocks, central spring element, and a drive motor comprising a drive shaft. A turntable is coupled with the drive shaft. The central spring element having a preloaded spring is centrifugally guided in a recess of the turntable. Either side of the spring is connected with a radially movable engaging tab element. Two different radially acting abutments are disposed on the central spring element and are movable towards recess. The engaging tab element has at least one engaging tab pointing radially inwards. The centrifugal block is attached to the engaging tab element. In the de-energized state of the drive motor, the engaging tab elements together with the centrifugal blocks disposed on them engage into detents of a frame-fixed detent disc with at least one engaging tab in a frictionally and positively locking manner. When voltage is applied and the drive motor starts, the engaging tabs disengage, the individual centres of mass of the central spring element, preloaded spring, the engaging tab element, the engaging tab, and two centrifugal block parts are on one symmetry axis. This invention creates a centrifugal positive blocking brake which is small in size and constructively simple and causes locking of the shutter when de-energized.