The most basic components of CNC and lathe machine include six parts: I/O device, CNC device, servo drive device, measurement feedback device, auxiliary device, and machine tool body.
1. I/O device of CNC and lathe machine
The I/O device is used for the input/output of CNC machining or motion control programs, machining and control data, machine parameters, coordinate axis positions, and the status of detection switches. Keyboard and display are the necessary and most basic I/O devices for CNC equipment.
2. CNC device of CNC and lathe machine
The numerical control device is the core of the numerical control system, which consists of I/O interface lines, controllers, arithmetic units and memory. The function of the numerical control device is to compile, calculate and process the data input by the input device through the internal logic circuit or control software, and then output various information and instructions to control each cnc lathing oem part of the machine tool to perform specified actions.
Among these control information and commands, the most basic ones are the commands such as coordinate axis feed speed, feed direction and feed displacement amount generated by interpolation, which are provided to the servo drive device. After being amplified by the driver, the displacement of the coordinate axis is finally controlled. These control information and instructions directly determine the movement path of the tool or coordinate axis.
3. Servo drive device of CNC and lathe machine
Servo drives are usually composed of servo amplifiers (also called drives, servo units) and actuators. In CNC machine tools, AC servo motors are generally used as actuators.
At present, linear motors have been used in advanced high-speed machining machines. In addition, among the CNC machine tools produced in the 20th century, there are also simple CNC machine tools using DC servo motors, and stepping motors are also used as actuators. The servo amplifier must be used in conjunction with the drive motor.
4. Measurement feedback device of CNC and lathe machine
The measurement feedback device is the detection link of the closed-loop (semi-closed-loop) CNC machine tool. Or the actual speed and displacement of the worktable, etc. are detected, and fed back to the servo drive device or numerical control device to compensate the feed speed or the motion error of the actuator, so as to achieve the purpose of improving the accuracy of the motion mechanism. The position where the measuring device detects the signal feedback depends on the structure of the numerical control system.
Servo built-in pulse encoder, tachometer and linear grating are all commonly used detection components. The advanced servo drive device of CNC and lathe machine adopts digital servo drive technology (referred to as digital servo) from professional the cnc parts supplier. The bus connection is used between the servo drive device and the numerical control device. The feedback signal is connected with the servo drive device in most cases. And transmitted to the numerical control device through the bus. Only in a few occasions or when an analog control servo drive (analog servo for short) is used, the feedback device needs to be directly connected to the numerical control device.
5. Auxiliary control mechanism of CNC and lathe machine
Auxiliary control mechanism refers to the control part between the numerical control device, the mechanical parts of the machine tool, and the hydraulic parts. Its main function is to receive the spindle speed, steering and start and stop commands output by the numerical control device, the tool selection and exchange commands, the start and stop commands of the cooling and lubrication devices, the loosening and clamping commands of the workpiece and machine tool components, and the table indexing and other auxiliary aids. The command signal, as well as the state of the detection switch on the machine tool, directly drive the corresponding actuator after necessary compilation, logic judgment, and power amplification, and drive the machine tool mechanical parts, hydraulics and pneumatics and other auxiliary devices to complete the actions specified by the command. It is usually composed of PLC and strong electric control loop. PLC can be integrated with CNC in structure (built-in PLC) or relatively independent (external PLC).
6. The machine body of the CNC and lathe machine
The machine body is the mechanical structure of the cnc and lathe machine. It consists of main drive system, feed drive system, bed, worktable, as well as auxiliary motion device, hydraulic/pneumatic system, lubrication system, cooling device, chip removal, protection system and other parts. In order to meet the requirements of CNC technology, give full play to the performance of the machine tool. Compared with ordinary machine tools, CNC machine tools have undergone great changes in the overall layout, appearance, transmission system structure, tool system and operational performance.