Patent ID: 7759601
Filing Date: 2010-07-20
Classification: B23K

Abstract:
1. An underwater laser processing apparatus, comprising: an optical unit that irradiates a condensed laser beam generated by a laser source and guided by an optical fiber to a certain point of an underwater workpiece; a nozzle having a gas exit for supplying gas to the certain point; and a bush that prevents a reflected laser beam from entering the laser source, wherein the nozzle comprises an area surrounding the gas exit extending to the surface of the workpiece for keeping the supplied gas between the nozzle and the workpiece, wherein the nozzle is formed as a disk having a flat surface area facing and extending along the workpiece and having the gas exit at the center thereof, wherein the nozzle has a circular groove extending in a circumferential direction on the flat surface area facing the workpiece, the groove being in the flat surface area and having a trench shape, and wherein the optical unit comprises a collimator lens that makes parallel the laser beam from the laser source, and a condenser lens that condenses the parallel laser beam.