History of NC Machines

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History of NC Machines

Numerical control machining began in the aircraft industry. Engineers wanted to make complex aircraft parts quickly and accurately. In 1947, two aircraft component contractors for the U.S. Air Force, John Parsons and Frank Stulen, perfected the use of three-axis curvature data to control machine tool motion.

In 1951, the government funded the Servomechanisms Lab of the Massachusetts Institute of Technology to design and build the first NC machine. The first prototype of a three-axis vertical milling machine debuted in 1952. Parsons was able to end mill and face mill an aluminum plate. Figure 1 shows an old NC milling machine.

Common CNC Machines[pic 2]

There are many types of CNC machines. The two most common CNC machines in the metalworking industry are:

1. Mills, or machining centers (Figure 1): Generally, the workpiece is held on the table while cutting tools perform their work.

1. Lathes, or turning centers (Figure 2): A workpiece spins as the cutting tools are brought in contact with it. Lathes create symmetrical pieces.

In every CNC use, a programmer plans the best way to cut the workpiece and then codes the movement of the tool. These instructions are interpreted by the computer controller. The controller then ensures that every part is handled in exactly the same manner for both small and large production runs. This process eliminates guesswork and the downtime involved while a human operator decides the best method for machining a part in the middle of production.

Other CNC Machines

Besides mills and lathes, you will find CNC systems in these machines as well:

1. Grinders: There are many different types of grinders, one of which is shown in Figure 1. Grinding is a finishing operation that creates a smoother surface.

1. Punch presses: Punching, or stamping, can apply large forces to sheet metal to create holes or bends. Some punch presses have one tool, as shown in Figure 2. The turret press is a punch press with several available tools, as shown in Figure 3.

1. Welders: There are several types of welding. The welder applies heat and a filler to fasten the pieces together.

You will also find CNC systems in operations that involve robotics, laser cutting, automatic testing machines, drafting systems, electronic assembly systems, and more. As you can see, computers have proven very useful in many aspects of manufacturing.

BEFORE YOU STAR!

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