CNC lathes are generally composed of input and output devices, numerical control devices (CNC), servo unit, drive (or actuator), programmable logic controller (PLC) and electrical control devices, auxiliary devices, lathe body and measuring device composition.

1 CNC lathe input and output devices, is the information exchange between numerical control system and the operator .realizing the man and machine interactive equipment.

2 Numerical control device (CNC device). is the core of the computer numerical control system,

It is composed of hardare and software. It receives the input signal from the device. The signal is through the CNC system software or logic circuit compilation,computing and logic processing, then Lathe Machine outputs various signals and instructions to control the various parts of the lathe.

3 Programmable logic controller (PLC).

CNC lathe is through CNC and PLC to complete the control function. CNC mainly complete digital operations and management ,such as part program editing, interpolation operationss.While PLC mianly complete logic actions. It receives the CNC control code M (auxiliary function), S (spindle speed), T (knife, tool change) and other switch action information,decording switch action information,then converting into the corresponding control signal,such as workpiece clamping, tool replacement, coolant switch and some other auxiliary actions.

4 The servo unit receives the speed and displacement commands from the CNC. These commands are converted and amplified by the servo unit and then converted to the speed, direction and displacement.

5 Drive device converts the command signal amplified by the servo unit into a mechanical movement,drives the table through the mechanical connecting part, makes the table precisely positioning or performs strict relative movement according to the prescribed trajectory,processing the shape, size and accuracy to meet the requirements.

The servo unit and the driving device are referred to as the servo drive system, which is the power unit of lathe machine.The instruction of the computer numerical control device depends on the servo drive system.

The servo drive device includes the spindle drive unit (main control spindle speed)and drive unit (mainly control the speed and position of the feed system). Servo drive system is an important part of CNC lathe

6 CNC lathe machine mechanical components,include main moving parts, feed movement components (table, pallet and its transmission components) and support components (bed, column, etc.), also including cooling, lubrication, indexing and clamping,other functions of the auxiliary device.Machining center machine tools also have magazine tool,automatic tool changer tools.As CNC Lathe Machine,because of high speed, high precision, large cutting volume and continuous processing requirements,

It will has higher requirement in precision, stiffness and vibration.

In addition, in order to ensure the functionof cnclathe machine, there are also some auxiliary systems, such as cooling system, lubrication system, hydraulic system, chip removal system and protection system.