The electric spindle is a new technology that combines the machine tool spindle and the spindle motor in the field of CNC machine tools in recent years.The main shaft is a set of components, including the electric spindle itself and its accessories: electric spindle, high frequency inverter, oil mist lubricator, cooling device, built-in encoder, tool changer, etc.The spindle motor and the machine tool spindle are combined into a transmission structure, so that the spindle components are relatively independent from the transmission system and the overall structure of the machine tool. The characteristics are high speed, high precision, low noise, and the inner ring with a lock. The structure is more suitable for spray lubrication