DISPOSITIF DE CHANGEMENT RAPIDE DE MANDRIN

L'INVENTION EST RELATIVE A UN DISPOSITIF DE CHANGEMENT RAPIDE DE MANDRIN 20 POUR BROCHE CYLINDRIQUE CREUSE 10 DE MACHINE-OUTIL.LE SUPPORT DE MORS 70 COMPORTE DES EVIDEMENTS RADIAUX TELS QU'UNE GORGE 72 DANS LESQUELS DES ELEMENTS D'ACCOUPLEMENT TELS QUE DES BILLES 50 SONT MAINTENUS, EN POSITION D'ACCOUPLEMENT, PAR UN MANCHON COULISSANT 58. CE MANCHON PRESENTE UNE GORGE INTERIEURE 60 QUI SERT D'ESPACE D'ECHAPPEMENT POUR LES ELEMENTS D'ACCOUPLEMENT LORSQU'IL EST DEPLACE AXIALEMENT, SOUS L'ACTION D'UN PISTON 36 CONTRE LA FORCE D'UN RESSORT 56 PAR L'INTERMEDIAIRE DE LA DOUILLE MOTRICE 32.LES MANOEUVRES SONT AINSI RENDUES RAPIDES, ET LA PARTIE HYDRAULIQUE PEUT ETRE PLACEE A DISTANCE DU MANDRIN. A quick-change mount for chucks is incorporated into a rotatable hollow spindle (10) of a machine tool and comprises servo-actuated drive sleeve (32) for power transmission to clamp the chuck (20) to the spindle flange (12). Slidable within the drive sleeve is a servodriven clamping sleeve (46) adapted for having fitted thereto the clamping jaw carrier (70) of the chuck. The clamping sleeve includes an annular series of holes (52) for guiding radially movable coupling element (50), which in order to get into coupling condition are displaced partially into a circumferential groove (72) of the clamping jaw carrier by means of a shifting sleeve (58), and in order to bring about the release condition are enabled to leave said groove for an annular recess (60) of the shifting sleeve (58). The shifting sleeve is spring biased into the condition to bring about the coupling position, from which it can be released by means of a catch member (64), when the fixation of the chuck is removed (FIG. 1).