CNC Machine

CNC : Computer Numerical Control
• Conventionally, an operator decides and adjusts
various machines parameters like feed , depth of
cut etc depending on type of job , and controls
the slide movements by hand. In a CNC Machine
functions and slide movements are controlled by
motors using computer programs.
It was in 1947 when numerical control was born. It began when John
C. Parsons of the Parsons Corporation, Traverse City, Michigan, a manufacturer
of helicopter rotor blades, could not make his templates fast enough. So, he
invented a way of coupling computer equipment with a jig borer. Mr. Parsons
used punched cards to operate his digit Ron system.
1949 was the year of another “Urgent need”. The U.S. Air Material
command realized that parts for its planes and missiles were becoming more
complex. Also, as the designs were constantly being improved, changes in the
drawing were frequently made. Thus, in their search for methods of faster
production, an Air Force study contract was awarded to the Parsons
Corporation. The servo mechanisms laboratory of the Massachusetts Institute
of Technology (MIT) was the subcontractor.
In 1951, MIT took over the complete job, and in 1952, the prototype of
today’s NC machine, a modified Cincinnati Hydrotel Milling Machine, was
successfully demonstrated. The term numerical control was originated at MIT.