Matthew W Mawhinney

US Patent:

20020127070, Sep 12, 2002

Filed:

Mar 7, 2001

Appl. No.:

09/800618

Inventors:

Matthew Mawhinney - New Castle PA, US

International Classification:

B23B047/24
B23B051/04

US Classification:

408/139000, 408/204000

Abstract:

Driving engagement is obtained between an arbor held in a machine tool and a collet holder that supports a drill bit by locking balls that are secured in engagement with drive surfaces by a locking ring. A nose cone is adjustably attached to the front of the locking ring and when the nose cone bottoms out on the workpiece, continued movement of the drill bit assembly relative to the nose cone assembly causes the locking ring to allow the locking balls to disengage the collet holder after ″ additional travel. Inner and outer springs reposition the clutch mechanism in its initial position for subsequent drilling operations.