Abstract:

The detection of filling-to-packing switchover point during injection molding plays a crucial role in ensuring the quality of the molded parts.Traditional detection methods, such as using predetermined screw cushioning or checking injection time have the disadvantages of depending on human experience and failure of adaptation to process parameter variations.This study presents a filling-to-packing detection method using the theory of singularity detection based on wavelet transform modulus maxima, according to the jump feature at filling-to-packing point.It adopted the pressure profile of a previous batch to obtain wavelet decomposition scale and switching threshold etc., and then used sliding window to conduct on-line detection of switch point.The experimental results indicated that the innovative switchover method yielded a more uniform product mass than any traditional methods.

Key words:

注射保压切换, 模腔压力, 小波变换, 奇异性检测

摘要： 针对注塑成型过程的关键步骤——注射保压切换，提出一种基于小波变换的切换点检测方法。它采用小波分析模极大值信号奇异性检测思想，根据模腔压力在注射保压切换时发生突变的特征，先利用以往批次生产的模腔压力信号，获取小波分解尺度、转换域值等信息，再使用滑动窗口法，实现切换点的在线检测。实验证明，在工艺参数变化的情况下，使用该方法生产出的制品，在重量上，较传统方法具有更好的一致性。

关键词:

注射保压切换, 模腔压力, 小波变换, 奇异性检测