Abstract:

：Hydrostatic spindles are core components of precision machine tools, which have been widespread used in mechanical engineering. As the main factor of hydrostatic spindle rotational error, the influence of the journal shape error on rotational error has not been revealed clearly. The error models of grinding of the shaft neck are analyzed and simplified. The equilibrium position of the spindle, considering the influence of the roundness error and cylindrical error, is received by use of the moving mesh method. The trajectory of a spindle from the concentric position to forming rotational error is simulated when the concavo or convex of the shape error in turn passed by the position of the minimum oil film thickness. The roundness error causing the spindle to form a rotational error is found, which is concerned with the frequency and amplitude of the journal shape error. The influence of the shape error of the journal on the hydrostatic spindle is revealed finally. The results of theoretical and experimental test are compared. The theoretical value is around 75.2 % of the experience. The results of theoretical calculation and the research method proposed have important theoretical significance and engineering reference value.

Key words: dynamic mesh method, rotational accuracy, shape error, hydrostatic spindle