The term CNC machine is widely used in the engineering world. The first question is, what is a CNC machine, or rather what does the acronym denotes. The abbreviation CNC stands for “Computer Numerical Control” and can be defined as a numerical control system that allows for the manufacture of machining tools using a dedicated program stored in a microcomputer. It is commonly used in the manufacturers of machine tools. It uses a set of computer instructions that helps mold or shape objects known as blanks into the desired shape required by the manufacturer. It can be used for various metals, wood, plastic, glass, and foam. The CNC machine is a device that contains multiple tools built into a cell that can be used in the manufacture of a three-dimensional object. In other words, it can be defined as a machine controlled by a computer that carries out its operation by a set of programs. The simples ones of the CNC machine can move in two axes while the advanced ones are capable of rotational motion.
The CNC machine was first developed in the 1940s and 1950s. Back then, punch tape was used as its storage technology. John T. Parsons developed the first CNC Machine; then, it was part of an air force research project. This would mark the beginning of CNC machine programming as well as the industrial era. Richard Kegg further developed the idea in 1952. then he built a Cincinnati Hydro-tel 28-inch vertical-spindle contour milling machine. This would later become the point for the future development of CNC machines. The punch tape storage system would later be replaced by analog computing technology, but by the end of the 1960s and early 1970s, digital technologies emerged, which was more efficient. The new CNC machine is still based on some of its ancestors’ components; they require a command function, a motion system, and a feedback system. Modern CNC are electronically controlled, and their outcome is easily predictable.
Parts of a CNC Machine
The following parts are found in the CNC machine:
The bed carries all the load on the CNC machine; they are usually made of hard materials. This is because the tool turrets travel over it.
The headstock is another main component of the CNC machine; besides, it has all the workpieces fixed into it to perform operations. It also has a motor that helps drive the main spindle.
The tailstock is the part of the CNC that provides the grip to any workpiece operating. This support is provided at the end of the CNC machine.
- Tailstock quill
The tailstock quill balances the workpiece between the tailstock and the headstock.
The footswitch is used to open or close the chuck to grip the component, similar to how the quillstock is taken forward and backward when gripping the workpiece.
This part of the CNC Machine is mounted on the main spindle, which gives space for fixing the workpiece.
- Tool Turrets
The tool turrets are where the tools are mounted and used for component machining. They vary in shape and the number of tools that can be used on them.
- Control panel
The control panel is a significant part of the CNC machine and is used to feed programs to the machine. It is similar to the human brain function and can otherwise be referred to as the brain in the CNC machine.
Elements of a CNC Machines
The elements of a CNC machine are
- Servo System
- Tape Reader
- CNC machine
They are sets of codes that tell the machine what to do, and they are of two sets: the G-code and M-code. The G-codes are used to command the machines’ specific movement, while the M-code is used for other commands apart from the axis motion.
The servo system is the element that receives and controls signals from the feedback device and gives output according to it. They are subdivided into three parts: servo motors, ball screws, and feedback devices.
it is a storage device where the programs are stored. Programs stored can be easily modified to fit the operators’ requirements.
It is the central control unit of the CNC machine; its function is to interpret the input language and convert it into machine language to carry out its function.
It is the complete machine that contains all the components.
Types of CNC Machine
There are different types of CNC machines, and they are used for various purposes.
- CNC lathe Machine
- 3-D printer
- CNC milling machine
- CNC- Router Machine
- CNC Laser cutting machine
CNC lathe machine
The lathe machine is used in production, which is a fast, efficient, and accurate machine. It is one of the most advanced types of CNC machines used in our modern-day. It uses a set of programs for its operations; once this program is fed into the computer, it commences operation. They are used for mass production.
The 3-D Printer is used for the printing of buildings with the drawings made by the CAD and CAM processes.
CNC Milling Machine
The milling machine is used to drill workpiece and produce slot. It carries out its operations just like the CNC lathe machine. They are known for accuracy and precision.
They are similar to the lathe and milling machine, but the difference is that it does all the carpenter work manually. The surface job done by this machine is perfect with a smooth finish.
Advantages of CNC Machine
- They help saves labor cost as it requires few workers to operate. The CNC machine majorly carries out the operations.
- The machine can efficiently perform the unit conversion.
- It requires low maintenance, thereby saving cost.
- They are better equipped with producing complex designs accurately within a short time frame.
- It is reliable and can run for the whole day.
- High production capacity.
Disadvantages of the CNC machine
- Computer knowledge is required to operate a CNC machine.
- In the case of machine failure, it requires skilled personnel to fix it.
- It is expensive to install.