QUADRUPLE-JAWED SELF-CENTERING CHUCK WITH CUNEIFORM BARS

摘要

The invention relates to devices for centering and securing parts for machining onto lathes and other machines. The disclosed chuck comprises a body having gripping jaws with oblique operating surfaces, and a device for resetting said jaws. The chuck further comprises cuneiform bars and a device for moving them, said device having nuts with right and left threads and a lead screw mounted in the body so as to permit its axial rotation. The chuck is further equipped with a clamp to guide the lead screw. The device for resetting the jaws has a maximum of two stops, which may be two pivoting stops with an excentric end protrusion. The common operating element for the jaws is formed from articulated sections of two cylindrical cogged wheels which operate in conjunction with an oblique, rack-type cog on the cuneiform bars.