<P>UNE MACHINE A USINER LES ENTRE-LAMES DE COLLECTEUR DE MOTEUR ELECTRIQUE COMPREND UN CHARIOT PORTE-OUTIL 19 DEPLACABLE SUR UN EQUIPAGE PORTE-OUTIL DANS LE SENS TANGENTIEL AU ROTOR PAR UN MOTEUR ELECTRIQUE 20. CE MOTEUR EST COMMANDE PAR UNE BOUCLE D'ASSERVISSEMENT DONT L'ELEMENT D'ENTREE EST UN DETECTEUR ELECTRO-OPTIQUE 24 MONTE SUR LE CHARIOT 19 ET ENTRAINE DE FACON A VISER L'ENTRE-LAME.</P>
The machine is based on a milling tool (23) mounted on a mobile gantry (19) which runs along the length of commutator gaps (17) parallel to the rotor axis. The rotation of the drill head is produced by a motor (15) linked to the tool via a flexible drive shaft (22) with universal joints. The milling tool assembly and driving motor are mounted on a mobile beam (10) which can be moved along sliding tracks (12,14) in perpendicular directions. Another motor (20), which is fixed with respect to the tool assembly, works in a servo-mechanism loop which includes an optical position-detector (23) fixed to the tool assembly to move the tool head. The milling tool is able to position itself correctly in the gap since the detector which is of the differential type, is able to distinguish, from the reflective properties, the position of the copper commutator surface (11) and the mica spaces.