Development of a deep-hole measuring system by using autocollimation principle (3rd report) - Measurement of roundness, cylindricity and straightness

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 detects the displacement of a feeler on the basis of the autocollimation principle. The optical system for light reception receives the laser beam irradiated from the measuring unit. In this research, the measuring accuracy and repeatability error of the system are evaluated by measuring the roundness, cylindricity and straightness of 110-mm-diameter holes of a ring gage and machined hole. As a result, it is clarified that the accuracies of the roundness, straightness and cylindricity measured by the measuring system correspond well to those by the tester in terms of both shape and value and that the repeatability error of 10 measuring measurements of roundness of machined hole is ± 0.4um.