Functional decomposition and reliability modeling technology study of CNC machine

Along with the social development, CNC machine tool is becoming more and more complex in its structure, while its reliability is becoming more and more important in the market. Since CNC machine tool functional reliability is more significant than its mechanical structural reliability, and the whole machine tool system’s functional reliability is guaranteed by every meta-action’s reliability, a new functional decomposition analysis method based on “Function—Motion—Action” (FMA) structure is put forward to support the reliability modeling of CNC machine tool. Firstly, the functional decomposition method is introduced, and the system decomposing process is obtained, then the unit functions and motion mechanisms of machine tool are analyzed. Secondly, the reliability evaluation model of machine tool based on meta-action is built, and the reliability evaluation models of every decomposing layer are listed. Finally, the gear grinding machine YK7236A is taken as an example to illustrate the validity and feasibility of this method.