| 摘要 |
The present invention relates to a processing gas supplying device of a laser processing head capable of preventing damage to a focusing lens by preventing the contamination of the underside of protective glass caused by a reverse inflow of contaminants around the laser processing head such as smoke through a nozzle during a break time from a laser non-processing mode such as after a temporary stop of a laser processing process in the middle of the laser processing process or after a stop of the laser processing process for a predetermined period or a complete finish of the laser processing process to a laser processing mode restarting the laser processing process, remarkably reducing laser processing defects such as a cut, and incredibly increasing a replacement cycle of the protective glass. To achieve this, the present invention, in the processing gas supplying device of the laser processing head enabling the laser processing process by supplying different kinds of multiple processing gases at a constant preset pressure to a lower side of the protective glass of the laser processing head to emit the gases toward an object to be processed through the nozzle with laser beams transmitted through protective glass, includes a contamination prevention gas supply means capable of preventing the contamination of the protective glass by supplying one kind of the processing gas among the multiple processing gases to the lower side of the protectively glass at a supply pressure lower than the preset pressure during the period from the non-processing mode of stopping the laser processing process while in the middle of the loser processing process to the laser processing mode restarting the laser processing process. The processing gas used for the contamination prevention gas of the contamination prevention gas supply means is nitrogen. In addition, the non-processing mode is operated in one case among after the temporary stop of the laser processing process, after the stop of the laser processing process for the predetermined period or the complete finish of the laser processing process. |
