Research On The System Of Rapid Measuring And Evaluating NC Machine Tool Error

With the development of industry, the traditional machine tools can hardly respond to the request of modern production. Fortunately, because of their special characteristics, CNC machine tools can suit these requirements. As a result, market demand on CNC machine tools increases. However during the process of producing and using the CNC machine tools, a simple, convenient, efficient and low-cost system of error-detecting, precision evaluation and error-compensation for the CNC machine tools becomes very important. To meet this requirement, a system has been designed and this paper will report the development of the system, and the research work that has been conducted.In the respect of the fast measurement of error, a set of easy fixing test accessory is designed in order to improve it. Thus it can reduce the time of measurement to a great extent. In addition the paper analyses NC machine tools feed to measuring the influence of the result.In the respect of precision evaluation, the software developed by the author is put into use. The software which integrates many precision evaluation criterions can make corresponding evaluation on the precision of the CNC machine tools, and can get evaluation parameter index and ocular evaluation table according to the standard that users select. And these offer a basis for analyzing error sources and improving their precision.In the respect of error compensation, this paper adopts four kinds of models of error compensation---cubic polynomial model, fit multinomial model and spline model. The corresponding compensation test has been done, and a comparative analysis of the result of compensation has been made. In addition, this system can follow the producer's selection of CNC system, and can automatically create error-compensation data file that is used for error compensation. Thus, fast error-compensation by CNC machine tools can be realized.This paper adopts two kinds of measuring instruments--linear grating and association micrometer with space gauge. Tests on the machine tools furnished with Huazhong I CNC system indicate that, through error-compensation, orient error can be reduced by 85%, and the reverse interval can be reduced by 90%. Compared with laser interferometer, efficiency can be raised by 3 times, and the price is its 5%...