Laser spot welding monitoring method and monitoring device

Abstract

The invention relates to a laser spot welding monitoring method and a monitoring device, wherein the laser spot welding monitoring method comprises the following steps: in the laser spot welding process, radiation signals of a molten bath are collected; the band-pass filtration is performed for the collected radiation signals to obtain band-pass signals; low-frequency direct-current components and high-frequency noise components in the radiation signals are removed; the fast Fourier transformation and the normalized power spectral transformation are performed for the band-pass signals to obtain molten bath characteristic signals; if the molten bath characteristic signals include spot welding characteristic frequency peaks, spot welding successful signals are output; and otherwise, spot welding unsuccessful signals are output. The laser spot welding monitoring method and the monitoring device can analyze the spot welding quality and determine if the laser power in the spot welding process is proper, have quick analysis speed and low cost, and can be preferably compatible with an existing laser spot welding technology. 本发明涉及一种激光点焊监测方法及监测装置，其中激光点焊监测方法包括以下步骤：在激光点焊的过程中，收集熔池的辐射信号；对收集的辐射信号进行带通过滤，获得带通信号；以去除辐射信号中的低频直流成分和高频噪声成分；对带通信号进行快速傅立叶转换和归一化功率谱转换，获得熔池特征信号；若熔池特征信号中包括点焊特征频率峰，则输出点焊成功信号；否则输出点焊失败信号。实施本发明的激光点焊监测方法及监测装置，能够分析出点焊的质量和点焊过程中激光的功率是否合适，分析的速度快，成本低，且能够很好的与现有的激光点焊技术相兼容。