The loss of electric spindle motor generates heat. It can be seen from the basic structure of the motorized spindle that the motor is installed inside the motorized spindle. While ensuring zero transmission and high precision machining accuracy, the main heat sources of the built-in motor stator and rotor loss heating and bearing friction heat generation are unavoidable. In addition, the stress on the end of the spindle during the load will also inevitably affect the heat generation of the non inner ring angular contact ball bearing. The heat generated by the heat source will inevitably lead to the increase of the temperature of the motorized spindle, which will inevitably lead to the thermal deformation of the spindle, which will have a great impact on the processing quality of the machine tool. Therefore, the heat generation mechanism of the motorized spindle is calculated and analyzed, and under this premise, the heat source is controlled to find the measures to reduce the temperature of the motorized spindle.

　　It can be seen from the basic structure of the motorized spindle that the motor is installed inside the motorized spindle. While ensuring zero transmission and high precision machining accuracy, the main heat sources of the built-in motor stator and rotor loss heating and bearing friction heat generation are unavoidable.

　　In addition, the stress on the end of the spindle during the load will also inevitably affect the heat generation of the non inner ring angular contact ball bearing. The heat generated by the heat source will inevitably lead to the increase of the temperature of the motorized spindle, which will inevitably lead to the thermal deformation of the spindle, which will have a great impact on the processing quality of the machine tool.

　　Therefore, it is of great significance to calculate and analyze the heat generation mechanism of the motorized spindle, control the heat source and find out the measures to reduce the temperature of the motorized spindle.

　　In addition to converting the effective input power of the electric spindle into mechanical power, a large part of it is also converted into the heat energy of the built-in motor, that is, the mechanical loss, electrical loss and magnetic loss will generate a lot of heat when the built-in motor is working.