Expansion chuck

Claim 1

MEANS FOR ATTACHING TO THE INSIDE AND END OF A HOLLOW ROLL CORE COMPRISING AN ARM, AN INSERTABLE CHUNK FOR GRIPPING THE INSIDE OF THE HOLLOW ROLL CORE MOUNTED ON SAID ARM AND PROJECTING OUT OF ONE SIDE THEREOF, SAID CHUNK COMPRISING A RIGID BODY INCLUDING AN END PLATE DISPOSED WITH ONE SIDE THEREOF FACING SAID ARM AND A FRUSTO-CONICAL CENTERING PORTION JOINED TO THE OTHER SIDE OF SAID END PLATE WITH THE LARGER DIAMETER END OF THE CENTERING PORTION NEXT TO SAID END PLATE, SAID END PLATE INCLUDING A MARGINAL PORTION THAT PROJECTS RADIALLY OUTWARDLY FROM SAID CENTERING PORTION, A SUBSTANTIALLY CYLINDRICAL EXPANSIBLE SECTION AXIALLY ALIGNED WITH SAID CENTERING PORTION HAVING A DIAMETER SUBSTANTIALLY THE SAME AS THE DIAMETER OF THE SMALLER DIAMETER END OF SAID CENTERING PORTION, SAID EXPANSIBLE SECTION HAVING STATIONARY ENDS MOUNTED ON SAID CHUNK BODY, SAID EXPANSIBLE SECTION HAVING ONE OF ITS SAID ENDS ADJOINING THE SMALLER DIAMETER END OF SAID CENTERING PORTION, MEANS FOR SHIFTING SAID ARM AND THE CHUNK THEREON IN A DIRECTION PARALLELING THE AXIS OF SAID CENTERING PORTION WHEREBY THE CHUNK MAY BE MOVED INTO A ROLL CORE WITH SAID END PLATE ABUTTING THE END OF THE CORE, AND MEANS FOR CIRCUMFERENTIALLY EXPANDING SAID EXPANSIBLE SECTION BETWEEN THE STATIONARY END THEREOF.