Laser machining apparatus

A laser machining apparatus comprising:

• an actuator to change relative positions of a machining head and an object to be machined, the machining head including a focusing system to focus a laser beam emitted from a laser oscillator and irradiate the object to be machined and a machining gas supply device to supply a machining gas to the object to be machined;
• a controlling circuitry to control in machining execution the laser oscillator, the machining head, and the actuator on a basis of a machining parameter, the machining parameter being a laser beam machining-related numeric parameter;
• a machining state observing circuitry to detect, from process light, light intensities in a plurality of predetermined wavelength bands of interest as a plurality of optical sensor signals, the process light being light generated from the object to be machined by laser beam irradiation;
• a feature extracting circuitry to extract at least one of features, the features being obtainable from an index of correlation between the plurality of optical sensor signals and from one of the optical sensor signals;
• and
• a correction quantity calculating circuitry to determine the machining parameter to be corrected as a correction parameter and a correction quantity for the correction parameter on a basis of the at least one of the features, wherein
• the correction quantity calculating circuitry
• includes an evaluating circuitry to determine for at least one of a plurality of machining defect items whether machining is good or bad on the basis of the at least one of the features in obtaining a determination result and
• determines the correction parameter to be corrected and a correction quantity for the correction parameter on a basis of the determination result,
• on the basis of the at least one of the features, the evaluating circuitry determines for at least one of the plurality of machining defect items a boundary value between a good machining range and a bad machining range, the good machining range being a machining parameter range where the determination result is good, the bad machining range being a machining parameter range where the determination result is bad, and
• in cases where the machining parameter corrected on a basis of the correction quantity is included in the bad machining range, the correction quantity calculating circuitry determines a degree of deviation, determines a correction quantity for the machining parameter and corrects the machining parameter during machining when the degree of deviation has gone beyond the boundary value, the degree of deviation being a difference between the machining parameter corrected on the basis of the correction quantity and the boundary value.