| 摘要 |
PURPOSE:To prevent more than needed increasing of a cutting width and to enable precision cutting by efficiently cooling the periphery of a cutting part. CONSTITUTION:A nozzle body 1 is made into double structures consisting of an inside cylinder la and an outside cylinder 1b. This inside cylinder 1a is internally provided with a condenser lens 2 and an assist gas is supplied into the inside cylinder la. This assist gas is blown from an aperture 1c of the inside cylinder 1a to the cutting part 3a of a work 3 and a cooling gas is supplied between the inside cylinder 1a and the outside cylinder 1b so that the cooling gas is blown concentrically with the cooling gas to the circumference of the cutting part 3a from the aperture 1d of the outside cylinder 1b. Since the periphery of the cutting part is efficiently cooled by the cooling gas, the more than needed increasing of the cutting width by an oxidation reaction is prevented. |
