Abstract: An electric commutator motor comprising a housing and a shaft which is solidly connected to a rotor. The housing comprises a stator and supply brushes which can be connected to an electric power source. The rotor is solidly connected to a commutator with bars, and comprises a set of wound turns, the ends of which are connected to two successive bars of the commutator. The housing comprises at least one additional brush which is positioned close to at least one of the supply brushes, known as the monitor brush, at a distance less than the width of a bar. The additional brush and the monitor brush are of the same thickness and are disposed symmetrically in relation to a diametrical plane of the rotor. The additional brush is connected electrically to a means for counting the pulses generated directly on the additional brush when the monitor brush leaves a bar of the commutator.