オートコリメーション方式深穴形状精度測定システムの開発（第2報）:　装置の試作および評価実験

摘要

穴深さlと穴径dとの比（l/d）が特に大きい深穴加工は切削加工の中でも難しい加工である．また，穴の評価に関しても加工と同様に，評価対象となる穴が深くなるほど測定精度は低下する．一般に穴の真円度，円筒度，真直度などは真円度測定器や三次元測定器で測定される．%The measuring system for evaluating the accuracy of a deep hole is developed by using the autocollimation principle. The system consists of a measuring unit and an optical system for light reception. The measuring unit comprises one laser diode, two mirrors, two quarter-wave plates, one polarizing beam splitter, and a feeler. The system detects the displacement of a feeler on the basis of the autocollimation principle. The optical system for light reception, which receives the laser beam irradiated from the laser diode in the measuring unit, comprises a plano-convex lens and a CCD camera. In this research, the measuring unit is manufactured for trial and its measuring accuracies are examined by using the basic experimental apparatus. As a result, the followings are clarified. The optimum values of the CCD image processing parameters are 60 in threshold and 250 μ s in exposure. The error of measurement by using the measuring unit is ±0.26 urn. Measurement error of its rotational angle is ±0.01° .