Explain working principle of CNC Machine.

Explain working principle of CNC Machine.
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Working principle of CNC Machine: In CNC machine, tape reader or any other input media is used for entry of part program. In CNC, entire program is first feed to the inbuilt computer memory. Once the program is stored, the machine cycle is then executed by the program. Software with control algorithms converts part program instruction into actions by the machine tool. This is done by generating pulses for each axis from the controller. Each pulse produces one small unit of motion (SUM). The slide travel is thus decided by the number of pulses. In a closed loop system, the pulses are feed to reference. The feedback device also send signal to the reference. These two signals are compared and necessary action is controlled.

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In case of Computer Numerical Control (CNC) machine tools, a dedicated computer is used to perform all the basic NC functions. The complete part programme to produce a component is input and stored in the computer memory and the information for each operation is fed to the machine tools, i.e. motors, etc. the part programmes can be stored in the memory of the computer and used in future.

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