How CNC machines work?

In CNC system a dedicated computer is used to perform all the essential functions as per the executive program stored in the computer memory. The system directs commands to servo drives to drive the servo motor other output devices like relays, solenoids, etc. to initiate the operations such as motor starting stopping, coolant on off, tool changing, pallet changing, etc. and other miscellaneous functions.

Once the system gives, it becomes necessary to ensure that the particular function has been completed. This is done by “Feed Back Devices.” Continuous feedback device like linear scale, encoder, resolver, etc. are used as position feedback of the motor. Some sensors like proximity switch, limit switch, pressure switch, flow switch, and float switch, etc. are used as feedback devices to monitor the different operations. Thus all operations of the CNC machine are monitored continuously with appropriate feedback devices. So that CNC system is called as “Closed Loop” system. In case of failure in any failure feedback, the system generates a “Fault Message.”

The principles of CNC operation.

Movement of X, Y, Z axis are controlled by a motor which supplies either Alternating current or Direct current.

Movement of the machine is done by giving commands.

All the operations are carried out by codes like speed, feed, depth of cut, etc.

For each operation separate code is available.

The warning system is available to save guard the various operations and components.

Types of CNC Controllers.

The main determining factor of CNC machine tools is the accuracy of programming. Programming needs to be done by the system. In the machining industry, the most commonly used systems for CNC machine tools are these: Japan FANUC CNC system, Germany Siemens CNC system, Japan Mitsubishi CNC system, Germany HEIDENHAIN CNC system and so on.