| 摘要 |
PROBLEM TO BE SOLVED: To provide a laser beam irradiating device in water which can execute the laser beam processing having high quality only by using a small quantity of gas under water atmosphere. SOLUTION: In the laser beam irradiating device in the water for heating and melting the surface of a material to be irradiated by irradiating the surface of the material to be irradiated with the laser beam in the water atmosphere, a mirror cylinder 3 holding a laser beam irradiating means and tightly closing the front surface, a shield gas nozzle 4 arranged so as to cover the front surface of the mirror cylinder 3, a shutter 6 arranged at the tip part of the shield gas nozzle 4 and preventing water leakage into the nozzle, a gas supplying device for supplying the shield gas into the shield gas nozzle 4 through a shield gas pipe 13 and a release 20 for driving to open/close the shutter 6, are integrally provided. Then, at the time of laser beam irradiation, the shield gas is supplied into the shield gas nozzle 4 and also, the shutter 6 is opened, and at the time of no irradiation of the laser beam, the shutter 6 is closed and the water leakage into the shield gas nozzle 4 is prevented. |
