CNC, short for Computer numerical control, is a kind of automatic machine tool controlled by program.
The control system can logically process the program with control code or other symbol instructions, through the computer to decode it, so that the machine tool to perform the specified action, through the cutting tool to process the blank material into semi-finished parts. Virtual CNC, an intelligent reverse simulation system for CNC machining, is a set of software that simulates the actual CNC controller and machine tool through the reverse post-processor and virtual machine tool, and checks the CNC machining process at the computer end. And it according to the machine, tool, blank and fixture information, to simulate machining CNC program, and can identify the error in the process of processing.
Numerical control (English name: NumericalControl for short :NC) technology refers to the use of numbers, characters and symbols composed of digital instructions to achieve one or more mechanical equipment action control technology. Numerical control generally uses general or special computer to achieve digital program control, so numerical control is also called computer numerical control (CNC), referred to as CNC, generally known as CNC abroad.
The control unit of a CNC machine tool
The operation and monitoring of NC machine tools are all completed in this NC unit, which is the brain of NC machine tools. Compared with ordinary machine tools, CNC machine tools have the following characteristics:
● High processing precision, with stable processing quality;
● Can carry out multi-coordinate linkage, can process the shape of complex parts;
● Machining parts change, generally only need to change the numerical control program, can save production preparation time;
● Machine itself of high precision, rigidity, can choose favorable processing amount, high productivity (generally 3~5 times of ordinary machine tools);
● Higher requirements for the quality of operators and higher technical requirements for maintenance personnel.
CNC machine tool composition structure
● Main Machine
It is the subject of CNC machine tools, including machine body, column, spindle, feed mechanism and other mechanical parts. It is a mechanical part used to complete all kinds of machining.
● Numerical control device
It is the core of CNC machine tools, including hardware (printed circuit board, CRT display, key box, paper tape reader, etc.) and the corresponding software, which is used to input the digital part program, and complete the input information storage, data transformation, interpolation operation and realize various control functions.
● Driving device
It is the driving part of the CNC machine tool executive mechanism, including the spindle drive unit, feed unit, spindle motor and feed motor, etc. He realizes spindle and feed drive by electrical or electro-hydraulic servo system under the control of numerical control device. When several feed linkage, can complete the positioning, straight line, plane curve and space curve processing.
● Auxiliary device
The necessary supporting parts of the exponential control machine to ensure the operation of the CNC machine, such as cooling, chip removal, lubrication, lighting, monitoring, etc. It includes hydraulic and pneumatic devices, chip removal devices, exchange table, CNC turntable and CNC indexing head, but also includes cutting tools and monitoring and testing devices.
Programming and other ancillary equipment
It can be used to program and store parts outside the machine. Since Massachusetts Institute of Technology developed the world's first numerical control machine tool in 1952, numerical control machine tools in the manufacturing industry, especially in the automobile, aerospace, and military industry has been widely used, numerical control technology in both hardware and software, there has been rapid development.
More impressive is the processing center
Summary of the basic knowledge of CNC machine tools
Machining center is a kind of highly automatic multi-function CNC machine tool with tool library and automatic tool changing device. The workpiece in the machining center after a clamping, can be more than two surfaces to complete a variety of processes of processing, and a variety of tool change or tool selection function, so that the production efficiency is greatly improved.
Machining center according to its processing process is divided into boring and milling and turning two categories, according to the number of control shafts can be divided into three axis, four axis and five axis machining center.