Method and device for diagnosing the quality of a laser welding bead

The invention relates to a method for diagnosing the quality of a laser welding bead made between two plastic parts, which comprises the following steps: a) measuring a set of ultrasound attenuations characterising the laser welding bead by moving an ultrasound sensor along the laser welding bead; b) calculating a weighted width Lp of the laser welding bead from an image showing all the ultrasound attenuations obtained; and c) comparing the weighted width Lp with a predetermined threshold weighted width Ls, the welding bead being considered to be acceptable if Lp is no lower than Ls. The invention also relates to the device implementing the method. 本发明涉及种用于对在两个塑料零件之间产生的激光焊道的质量进行诊断的方法，所述方法包括以下步骤：a)通过沿所述激光焊道移动超声波传感器来测量表征所述激光焊道的组超声波衰减；b)从示出了所获得的所有所述超声波衰减的图像中计算所述激光焊道的加权宽度Lp；以及c)将所述加权宽度Lp与预定阈值加权宽度Ls进行比较，如果Lp不低于Ls，则所述焊道被视为可接受的。本发明还涉及用于实现这种方法的设备。