Patent DE-102011004236-A1 (DE)
Title: Cutting device for cylindrical workpiece for cutting hollow cylindrical workpiece of metal in several metal rings by laser beam, which is applied by laser beam source, comprises retaining element having side wall, and pressure element
Inventor: NAKAJIMA KATSUYUKI
IPC: B23K26/38
Filed: 2011-02-16
Abstract: The cutting device (10) for a cylindrical workpiece for cutting a hollow cylindrical workpiece of a metal in several metal rings by a laser beam, which is applied by a laser beam source, comprises a retaining element having side wall, which is inserted in a through-hole of the cylindrical workpiece, where the retaining element serves as cooling device for cooling the workpiece and the side wall of the retaining element is displaceable towards an inner wall of the through-hole of the cylindrical workpiece and displaceable away from the inner wall of the through-hole of the workpiece. The cutting device (10) for a cylindrical workpiece for cutting a hollow cylindrical workpiece of a metal in several metal rings by a laser beam, which is applied by a laser beam source, comprises a retaining element having side wall, which is inserted in a through-hole of the cylindrical workpiece, where the retaining element serves as cooling device for cooling the cylindrical workpiece and the side wall of the retaining element is displaceable towards an inner wall of the through-hole of the cylindrical workpiece and displaceable away from the inner wall of the through-hole of the cylindrical workpiece. When the side wall of the retaining element is inserted in the through-hole of the cylindrical workpiece, the side wall is displaceable towards the inner wall of the through-hole and the inner wall presses, so that the cylindrical workpiece is deformed in a circular mold. The cylindrical workpiece, which is deformed in the circular mold, is cut by the laser beam. The cutting device further comprises a pressure element (80), which is inserted in an interior of the retaining element and has a first cam (88) on an inner wall of the element, where the first cam is tapered, so that a diameter of the cam progressively decreases in a longitudinal direction of the cam. A diameter of the pressure element is formed to be increased or to be decreased. The cutting device has a diameter changing element, which has a second cam for contacting with the first cam, where the diameter changing element is displaceable in directions along a longitudinal direction of the pressure element and is inserted into and separated from the interior of the retaining element in these directions. When the diameter changing element is displaceable in the directions, the second cam is contacted with the first cam to press the first cam, so that the diameter of the pressure element is increased to push the retaining element from the interior. The retaining element is displaced towards the inner wall of the through-hole of the workpiece. When the diameter changing element is displaced in the direction, i which it is separated from the interior of the pressure element, the first cam is relieved by a pressure by the second cam to reduce the diameter of the pressure element in a direction, in which it is separated from the retaining element. The retaining element is displaced in a direction away from the inner wall of the through-hole of the workpiece. The cutting device includes coolant channels, which extend in a circumferential direction along the side wall of the retaining element and through which the coolant flows. The laser beam source stops at a position of one of the coolant channels and the laser beam radiates at the position to cut the cylindrical workpiece. The cutting device has a suction unit for sucking the coolant, which flows out through a cut section when the cylindrical workpiece is cut, and a transfer agent delivery unit for delivering a transfer agent, which transfers the coolant to the suction unit, where the coolant is leaked through the cut section. The laser beam source cuts the workpiece from downstream to upstream in a direction, in which the coolant is supplied.