統計製程管制於砂輪再削銳時機之判斷

The Determination of Redressing Timing for Grinding Wheel by Using Statistical Process Control

本文研究統計製程管制圖運用在平面磨床以加速度信號判斷砂輪再削銳時機之可行性。平面磨床研磨加工物件時，砂輪逐漸磨耗，當連續研磨加工時，砂輪表面由正常、堵塞、脫落以致於鈍化，為了檢測出砂輪狀態，掌握其再削銳時機，擷取主軸頭之加速度信號，以時間序列統計參數分析，萃取砂輪狀態之統計特徵參數，再將其統計特徵參數帶入統計製程管制，以管制圖監控統計特徵參數是否超差，當超差開始發生時作為砂輪再削銳時機。

This study explored the feasibility of statistical process control diagramsused in surface grinders in order to accelerate signal determination andtiming for grinding wheel resharpening. When processed pieces are groundon a surface grinder, the grinding wheel gradually wears, and when engagingin continuous grinding processing, the grinding wheel surface changes fromnormal, congestion, chip-off to passivation. To detect the grinding wheelcondition and grasp the timing for resharpening, the acceleration signals ofthe spindle were extracted. Then, the tine series statistical parameters were adopted for the analysis. The extracted statistical characteristic parametersof the grinding wheel condition were extracted, and the statisticalcharacteristics parameters were entered into the statistical process control.Control diagrams were used to monitor whether or not the statisticalcharacteristic parameters were out of tolerance. The time out of tolerancewas the timing for grinding wheel resharpening.