Scroll Parts Automatically Detection System Development Based On Coordinate Measuring Technology

Three-jaw chuck is one type of general machine tool accessories. Its accuracy has a direct influence on the machine tool spindle’s dynamic balance. Three-jaw chuck’s scroll is one of the critical parts to determine the self-centering accuracy. Therefore, it is significant to control its quality. Nowadays, three-jaw chuck is measured by using two typical methods, static discrete or dynamic continuous. However, this existing specified measuring apparatus has following defects,1) high cost,2) low accuracy and3) low efficiency. In this thesis, a novel approach is developed to measure the plane thread error from different specifications scrolls based on coordinate measuring technology by means of general measurement coding. The advantages of this new method are rapid response, high accuracy and batch measurement. The thesis’s contents are shown as following,Depth analysis of scroll’s structure. The measurement scope was determined and corresponding measurement principle and validation plan was developed. Employing geometric principles, the theoretical line of scroll’s plane thread was analyzed based on measured curve modeling. Components’contour degree error evaluation method was also discussed.As per the principles of measurement path safety and path optimization, the components’measurement path was planned based on product CAD model. The following coding key factors were discussed,1) components coordinate system determination,2) starting point determination,3) measurement data processing and preservation, and4) measurement program optimization.As per scroll’s measurement requirements, a general measurement program was developed based on advanced coding language of three-axis software. The automatic measurement for different size of scroll was developed. The general measurement of scroll, including parameters selection, data processing, measurement results chart output and print-out, was achieved. Measurement data processing and MSA. The factors which affect measurement results were analyzed by utilizing testing data. The uncertainty analysis was done for the parameters which affect measurement results. Calculated standard uncertainty and the expanded uncertainty was synthesized.The test results show that this thesis not only contains highly reliable technique, but also meet all the general requirements of different types of scroll by employing the appropriate measurement principles. According to the experimental results, considering the various factors and analysis of error causes improved the quality of the scroll parts direction.