Multi-spindle chucking machine

A machine tool comprising:

• a frame;
• a plurality of spindles each rotatable about an axis and each including a chuck at a first end of the spindle, a driven clutch member at a second end of the spindle, and means intermediate said ends for operating the chuck to respectively engage or release a workpiece to be machined;
• a carrier supporting said spindles in axially parallel postions with said chuck and driven clutch member accessible at respective first and second ends of the carrier and said chuck operating means accessible between said ends;
• means supporting the carrier for turning about a longitudinal axis parallel to said spindle axes;
• means for indexing the carrier about said longitudinal axis to move the spindles between defined stations;
• locking means acting between the frame and carrier and operable to lock the carrier with respect to the frame in each of a plurality of defined angular positions and precisely locate the spindles at said stations;
• the carrier support mans, indexing means and locking means permitting access to said chuck operating means of all of the spindles when the spindles are at said defined stations;
• and,
• spindle drive means supported by said frame adjacent said second end of the carrier and including a number of individual spindle drive mtors each disposed in a fixed position aligned with one of said stations, and, in association with each said motor, clutch means including a driving clutch member co-operable with a said driven clutch member of a spindle at a relevant said station, said clutch means being operable to drivingly couple each spindle drive motor to the relevant one of said spindles by engagement of said clutch members when the carrier has been indexed to bring that spindle to a said station at which a machining operation is to be performed, and being disengageable to permit indexing of the carrier.