Summary: | 碩士 === 國立雲林科技大學 === 機械工程系 === 105 === With the advanced development of precision mechanical technology, the requirements of dimensional accuracy of the work-piece are enhanced relatively. Positioning accuracy calibration is a necessary procedure for machine tools before delivery. However, the commercial measuring equipment is not cost-friendly. Therefore, the automatic compensation modules of the positioning error for X-axis and the indexing error for C-axis are constructed by the laser interferometer and the rotary encoder system respectively. Further, the compensation data of the positioning error will be transferred into the controller by connecting the measurement program with the controller. Consequently, the measuring time and the personal errors can be reduced.
Alignment of the optical axis to the linear axis (X, Y and Z) is an important procedure before calibrating the machine tools with the laser interferometer. The purpose of the procedure is to eliminate the cosine error caused by the misalignment. The module of the automatic alignment for the optical axes takes around 106 seconds to reduce the cosine error to 1 nm in the measuring range of 240 mm in the fine-tuning stage. Furthermore, the complex installation process of the laser interferometer and low efficiency of manual operation can be ameliorated.
The inspection system of cross-sectional profile has been constructed in this study. The system is composed of the linear axis (X-axis) and the rotating axis (C-axis) for measuring the cross-sectional profile of dual-axes (X-C) during the synchronized motion under free-loading states. The measurement results indicate that the maximum contour error is reduced to 5.7 μm after the compensation of the positioning error and the measurement results reveal that the calibration is a critical procedure for dimensional accuracy of the work-piece. Hence, the inspection system with the advantages of simple operation and low cost has been developed to improve the machining accuracy of machine tools, and enhancing the competitiveness of precision machinery industry.
Keywords: Automatic alignment of the optical axis、Linear axis、Rotary axis、Automatic compensation、Error measurement of the cross-sectional profile
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