Geometric Error Modeling and Sensitivity Analysis of CNC Internal Circular Compound Grinding Machine

Abstract

In order to improve the machining accuracy and efficiency of the hole and sleeve parts, it is necessary to improve the overall grinding accuracy of the CNC (Computer Numerical Control) internal cylindrical compound grinding machine more accurately and efficiently. First of all, it is necessary to clarify the degree of influence of each error parameter on the grinding accuracy, and compensate each error according to the different degree of influence. In this paper, modeling calculation analysis is carried out for a certain type of CNC internal cylindrical compound grinding machine. Firstly, based on the theory of multi-body system dynamics, the topological structure of the CNC internal cylindrical compound grinder is established. According to the topological structure, the position, motion matrix and error matrix of the moving parts of the grinder are written. After data processing, the numerical control internal cylindrical compound grinder is calculated. Use this model to derivate each error parameter to obtain the sensitivity expression of each error parameter. After the actual structure parameters of the grinder are brought into the expression, the sensitivity coefficient of each error parameter can be determined by normalization treatment. The key error parameter with larger sensitivity coefficient is the key error parameter. Finally, several error parameters which have the greatest impact on the overall grinding accuracy of the grinder are obtained. This method provides the basis for the improvement of the grinding accuracy of the subsequent grinder, and creates conditions for the improvement of the machining accuracy of sleeve parts.