Abstract:As centering small roller jig moving cam theoretical curve equation is complex and difficult to implement CNC machining directly, a numerical method was proposed to solve this CNC machining problem. The structure and working principle of the centering small roller jig were introduced;an equal step sampling calculation numerical solution method of moving cam curve was proposed; then,these samples were interpolated and fitted in accordance with quadratic polynomial curve, and the parameter values were set.At last,the calculated quadratic polynomial curves were compared with the actual theoretical curves.It is found that the validation error is much smaller than conventional processing error produced by the theoretical curve. Analysing the comparison error,refining the sampling step length and piecewise interpolation fitting loop calculation methods were proposed to improve accuracy.The results show that: the moving cam numerical method can effectively solve the difficult process problem of moving cam with better economic benefits.