| 摘要 |
PURPOSE:To prevent the sticking of cooling water and molten metal on a lens, by providing assist gas guides in nozzles for ejecting an assist gas and irradiating a laser beam and providing a slight space parts between the guides and a nozzle. CONSTITUTION:A nozzle assembly 41 consists of an inside nozzle provided with an ejection port 43 for irradiating a laser beam LB together with an assist gas to the work W, and an outside nozzle provided with a passage 45 and an ejection port 47 for ejecting a coolant. The 1st assist guide part 97 of a funnel shape is internally mounted in the large diameter part in the bore of an inside nozzle body 49 and the 2nd assist guide member 99 of the same shape is internally mounted in the small diameter part in the lower part. Slight space parts 101, 102 are provided between these guide members 97, 99 and the inside nozzle body 49. Since the assist gas is ejected at the flow rate increased by the guides 97, 99, the sticking of the cooling water and molten metal from the cutting part on the lens is prevented and even if some infiltrates the same, the intruded cooling water and molten metal are entrained in the parts 101, 102 and are prevented from intruding upward. |
