光学透镜注射成型过程的在线声发射信号监测

Online AE Signals Monitoring in Injection Molding of Optical Lens

基于声发射技术与信号小波包分解,采集成型过程的声发射信号,分析注射成型工艺如注射速度、注射压力、模具温度等对于声发射信号的影响以及有无流动缺陷时声发射信号的区别。实验结果显示,随着注射速度升高或者模具温度的降低,信号能量明显升高。另外注射速度、注射压力和模具温度共同影响信号在375-500k Hz频段能谱系数。缺陷检测实验也表明当375-500k Hz频段能谱系数大于0.1时,二次透镜表面存在缺陷。注射成型过程的声发射信号尤其是375-500k Hz频段信号完全能够反映出工艺参数变化和成型过程熔体流动情况,并且能够实现成型流动缺陷的在线监测。

The acoustic emission technique is used to capture the acoustic emission signals during injection molding under different process parameters. The signals are processed by using the wavelet packet decomposition to analyze the impacts of injection molding process parameters such as injection speed, injection pressure, mold temperature on the AE signals. The Experimental results show that the signal energy is significantly higher. In addition the injection speed, the injection pressure and the mold temperature effect signal 375-500kHz band spectrum coefficient together which can be used to monitoring the flow of melt. Defect detection experiments also show that when the 375-500kHz band spectrum coefficient is greater than 0.1,some defects occur on the surface of second lens. The acoustic emission signals of injection molding process and process parameters are inseparable, and the AE signals can fully reflect the molding process especially the signal of 375-500kHz band. It is easy to achieve the online monitoring of defects during the flow process based on acoustic emission technology.