The spindle of a CNC lathe can usually take the following three forms:

1. Direct-drive spindle: The direct-drive spindle of CNC lathes is directly driven by the motor without a transmission device. It can achieve high-speed, high-precision processing, and has the advantages of fast response speed and stable rotation speed. CNC lathe direct-drive spindles are usually used where high-speed machining and precision machining are required.

2. Belt drive spindle: The CNC lathe belt drive spindle transmits the power of the motor to the spindle through the belt drive device. It can achieve various speed adjustments and speed changes, is suitable for various processing needs, and is relatively easy to maintain.

3. Gear-driven spindle: The gear-driven spindle of a CNC lathe transmits the power of the motor to the spindle through a gear transmission device. The CNC lathe has high transmission efficiency and stability and is suitable for processing occasions that require high transmission efficiency, such as large Torque machining or heavy duty machining.

The three spindle types of CNC lathes each have their own advantages and disadvantages. Choosing the appropriate spindle type depends on the specific processing needs, workpiece type and processing requirements.