US Patent No. 10,928,615

LASER PROCESSING DEVICE HAVING APPROACH FUNCTION OF PROCESSING HEAD


Patent No. 10,928,615
Issue Date February 23, 2021
Title Laser Processing Device Having Approach Function Of Processing Head
Inventorship Atsushi Mori, Yamanashi (JP)
Tatsuya Mochizuki, Yamanashi (JP)
Assignee Fanuc Corporation, Yamanashi (JP)

Claim of US Patent No. 10,928,615

1. A laser processing device configured to transmit a laser beam toward a processing head, condense the laser beam by a light condense optical system, and carry out laser processing by vertically irradiating the condensed laser beam to an article to be processed, the laser processing device comprising:a processor configured to:
prior to the laser starting irradiation, set a light condensing point distance between a light condensing point of the laser beam and a surface of the article, so that the light condensing point of the laser beam is separated from the surface of the article when the laser beam starts irradiation, and
after starting irradiation and processing of the surface of the article at the set light condensing point separated from the surface of the article, move the light condensing point from the point separated from a surface of the article to the surface of the article, while irradiating the laser beam and the processing the surface of the article,
wherein the light condensing point distance is computed, prior to the laser starting irradiation, so that an amount of the laser beam reflected by the surface of the article and returned to a laser light source through the light condense optical system is not more than an allowable value when the laser beam starts the irradiation and the processing of the surface of the article;
a movement velocity limiting part configured to limit a movement velocity of the processing head to a predetermined velocity, after the processing head reaches the position corresponding to the light condensing point distance; and
wherein the processor is further configured to move, at a predetermined velocity, the light condensing point from the point separated from a surface of the article to the surface of the article while irradiating the laser beam, the predetermined velocity is set to ensure that the surface of the article is irradiated for a time period required to melt the surface of the workpiece.