Abstract: In order to deeply discuss the internal heat transfer and heat dissipation mechanism of permanent magnetism synchronous motorized spindle, the heat generation of its builtin permanent magnetism motor and bearing was theoretically analyzed, and the heat generation of the bearing and motor inside the spindle was quantitatively calculated. According to the knowledge of modern heat transfer, the definite solution condition of temperature field was determined. The thermal characteristics of the motorized spindle were analyzed in Ansys, and the influence of temperature field on the stress, strain and displacement of the structure was solved by thermal structural coupling analysis. The results indicate that there is a big temperature discrepancy in each component of motorized spindle, the temperature rise between the bearing end and the spindle front end is serious, and the temperature difference between stator and rotor is huge, and the temperature increase tendency of the interior components of the spindle is no distinction. Hence the steps to perfect the thermal characteristics of motorized spindle were put forward, such as strengthening the heat dissipation of the parts with severe temperature rise and reducing the heat generation of the bearing.

Key words: motorized spindle; thermal characteristics; finite element analysis; temperature field analysis