The structure of CNC machine tools


CNC machine tools are generally composed of input and o […]

CNC machine tools are generally composed of input and output devices, numerical control devices, programmable controllers, servo systems, detection feedback devices and machine tool hosts.

1. Input and output device
The input device can transmit different processing information to the computer. In the early days of the emergence of CNC machine tools, the input device was perforated paper tape, which has now become obsolete; at present, the use of keyboards and disks has greatly facilitated the work of information input.
Output refers to the output of internal working parameters (including the original parameters under normal and ideal working conditions of the machine tool, fault diagnosis parameters, etc.). Generally, these parameters need to be output for record keeping when the machine tool is just working. After working for a period of time, the output will be compared with the original Data comparison and comparison can help determine whether the machine tool works normally.

2. Numerical control device
The numerical control device is the core and leading of the numerical control machine tool, which completes the processing and calculation of all processing data, and finally realizes the command work of the various functions of the numerical control machine tool. It contains microcomputer circuits, various interface circuits, CRT monitors and other hardware and corresponding software.

3. Programmable controller
That is, PLC, which controls the spindle unit, processes the speed commands in the program to control the spindle speed; manages the tool magazine, performs automatic tool exchange, tool selection, cumulative tool usage, tool remaining life, and tool sharpening times, etc. Management; control the spindle forward and reverse rotation and stop, exact stop, cutting fluid switch, chuck clamping loosening, manipulator taking and feeding tools, etc.; also control the external switches of the machine tool (travel switch, pressure switch, temperature control switch, etc.) ; Control the output signal (tool magazine, manipulator, rotary table, etc.).

4. Detection feedback device
Composed of detection elements and corresponding circuits, it mainly detects speed and displacement, and feeds the information back to the numerical control device to realize closed-loop control to ensure the machining accuracy of the numerical control machine tool.

5. Machine tool host
The main body of the CNC machine tool, including the machine body, spindle, feed transmission mechanism and other mechanical parts.