Abstract: A torsion damping device in a clutch plate is fitted with an interposing element comprising two movable centrifugal plates. According to the invention, the two movable plates are connected to one another by at least one transmission element which is rotatable relative to the plates in such a way that a radial displacement of one of the movable plates causes rotation of the transmission element and a radial displacement in the opposite direction of the other movable plate.

Abstract: The values of a binary frequency error signal are periodically transmitted to the generator to be controlled, through a narrow band channel. A sequence detector circuit records the successive received values of the frequency error signal and as a function of the last two received values, controls a modulated pulse generator circuit in order to form a variable-amplitude correction signal. The amplitude of the correction signal is reduced with each change in the value of the frequency error signal received, whose changes in value reproduce changes of a phase error signal.

Abstract: The comparator comprises a circuit for detecting the sign of the phase-shift of the reference signal relatively to the second signal for a predetermined phase of the latter. It delivers a corresponding binary phase difference signal.A second circuit selects those changes in values of the phase difference signal which occur for a phase of the reference signal comprised in a predetermined phase interval, and are thus surely representative of a change in the sign of the frequency difference.