Abstract: A reflected beam detector detects a reflected beam reflected from a sheet metal when the sheet metal is irradiated with a laser beam so that the sheet metal is cut. A processing state determination unit is provided with a standard deviation value calculation unit and a quality determination unit. The standard deviation value calculation unit calculates, in a predetermined calculation cycle, a standard deviation value of a reflected beam detection value at a monitoring wavelength from among reflected beam detection values in a predetermined wavelength band output from the reflected beam detector. The quality determination unit determines whether or not a burning defect has occurred in which a cut surface of the sheet metal is excessively melted based on a comparison result of comparing, with a first threshold value, the standard deviation value calculated by the standard deviation value calculation unit.

Abstract: A laser cutting nozzle includes an inner nozzle and an outer nozzle. The inner nozzle exhibits a tube shape having a through hole on an axis and having a diameter decreasing on a first end portion side and includes a notch extending in the axis direction along an outer peripheral surface on a second end portion side. The outer nozzle is fitted to the outer peripheral surface of the inner nozzle and includes a vent passage including the notch and communicating between the first end portion and the second end portion in the axis direction. A minimum flow cross-sectional area of the vent passage matches an opening area of the notch in an end surface on the second end portion side.

Abstract: (1) A shape of a distal end face of a nozzle of a laser processing head of a laser processing machine is image-captured by a camera, (2) a position of the center of a nozzle hole is calculated based on the shape of the distal end face, (3) a test beam is irradiated from the nozzle hole, (4) the shape of the distal end face of the nozzle is image-captured while the test beam is being irradiated to calculate a position of the test beam, (5) a positional error between the center of the nozzle hole and the test beam are calculated, and (6) a beam path adjusting mechanism that adjusts an incident angle of the test beam onto a condenser lens in the laser processing head is controlled based on the positional error to make the center of the nozzle hole and the test beam coincident with each other.

Abstract: A laser cutting nozzle includes an inner nozzle and an outer nozzle. The inner nozzle exhibits a tube shape having a through hole on an axis and having a diameter decreasing on a first end portion side and includes a notch extending in the axis direction along an outer peripheral surface on a second end portion side. The outer nozzle is fitted to the outer peripheral surface of the inner nozzle and includes a vent passage including the notch and communicating between the first end portion and the second end portion in the axis direction. A minimum flow cross-sectional area of the vent passage matches an opening area of the notch in an end surface on the second end portion side.