Patent ID: 8487207

Claim:
An apparatus for cutting a hollow cylindrical workpiece of metal with a laser beam to produce a plurality of metal rings, comprising: a rotatable workpiece holder for holding the hollow cylindrical workpiece thereon, the rotatable workpiece holder having a side wall insertable in a through hole of the hollow cylindrical workpiece and functioning as a chiller for cooling the hollow cylindrical workpiece when the side wall is inserted in the through hole of the hollow cylindrical workpiece, the workpiece holder having a coolant passage defined longitudinally therein for passing a coolant therethrough along the side wall and a plurality of branch passageways which extend from the coolant passage to an outer surface of the side wall; whereby the coolant cools the hollow cylindrical workpiece to be cut by the laser beam when the coolant flows from the coolant passage through the branch passageways between the outer surface of the side wall and an inner circumferential surface of the hollow cylindrical workpiece.