Electric spindle heat pipe cooling system based on high speed machine tool

3. Cooling system design of high speed electric spindle using heat pipe cooling technology

The spindle cooling system using heat pipe technology not only cools the shaft housing, but also increases the cooling of the high speed spindle core as shown in Figure 3. By fitting the heat pipe into the housing and the shaft core of the electric spindle for the electric spindle, the front end bearing, the motor stator and the rear end bearing are all set as the evaporation section, and the heat pipe part which exposes the rear end cover is set as the condensation end. A cooling air conditioner is installed on the machine tool, and by pressurizing, cold air flows in from the inlet of the rear end cover, and finally flows out from the outlet and is circulated to the cooling air conditioner for cooling. When the machine is working, once the heat is generated at the evaporation end, it will quickly pass through the steam inside the heat pipe to the condensation section, and when the cold air is encountered at the condensation end, the heat will be quickly taken away to ensure the constant temperature state of the electric spindle. The efficient heat pipe heat conduction technology can quickly take away the heat on the spindle motor and the spindle bearing, which can effectively control the temperature rise, minimize the machining accuracy error caused by the thermal expansion of the spindle, and also improve the shaft itself and the spindle bearing. Service life.

Figure 3 Cooling design of the electric spindle using heat pipe technology

4, the conclusion

The use of high-speed electric spindle heat pipe cooling technology can effectively reduce the machining accuracy error caused by the thermal expansion of the shaft. In the case that the machine tool spindle can withstand, the spindle speed can be further improved, and the machining efficiency of the machine tool is higher. At the same time, it can also alleviate the thermal expansion of the electric spindle bearing and improve the service life of the bearing. The rotational speed of the domestic CNC machine tool spindle has not been improved, and the main reason is the internal heat dissipation problem at high speed. The electric spindle heat pipe cooling technology can effectively solve the internal heat dissipation problem of the high speed electric spindle.