Patent ID: 8212175

Claim:
A computer-program that can be loaded directly into the memory of a computer and comprises portions of software code for implementing a method for controlling the quality of a laser-welding process of laser welds of semifinished products constituted by elements of sheet metal of different thickness and/or properties, said method comprising the steps of: detecting a radiation produced in the welding area and issuing signals indicating said radiation, acquiring and processing said signals indicating said radiation, making a division into temporal blocks of said signals indicating said radiation, calculating for each block a block-mean value and comparing each of said block-mean values with a value that is a function of the mean of the acquired signal indicating the radiation, identifying blocks characteristic for the mean on the basis of said operation of comparison, and calculating for each block a value of block standard deviation and comparing each of said values of block standard deviation with a value that is a function of a reference standard deviation, identifying blocks characteristic for the standard deviation on the basis of said operation of comparison, wherein the method comprises a procedure of classification of the quality of a parametric type that envisages supplying a plurality of input values, said procedure comprising the operations of: supplying input values comprising values of block mean and values of block standard deviation corresponding to said blocks characteristic for the mean for identifying defects and/or porosities; and supplying input values comprising values of block standard deviation corresponding to said blocks characteristic for the standard deviation for identifying insufficient penetration, wherein, prior to said procedure of classification, the method comprises an operation of selecting characteristic blocks for the mean corresponding to characteristic blocks for the standard deviation as combined-characteristic blocks, and wherein the method envisages arranging said block-mean values and values of block standard deviation as respective dimensions in a map with at least three dimensions that comprises, as a third dimension, a block temporal length, when the computer-program is run on the computer.