What is the function of rotary encoders in CNC milling?

Rotary encoders serve a critical role in CNC milling by providing precise feedback on position and speed. They are devices that convert the angular position or motion of a shaft into an electrical signal that can be read by a controller. By utilizing rotary encoders, the CNC machine can determine exactly where the tool is positioned on the workpiece and monitor the speed at which it is moving.

This feedback is essential for maintaining accuracy and consistency in machining operations. It allows for closed-loop control, where the CNC system can continually adjust its actions based on the actual measurements provided by the encoders. This results in improved precision, as the system can correct any deviations that may occur during machining due to factors like tool wear or material inconsistencies.

In contrast, other options do not relate to the primary functions of rotary encoders in CNC milling. Measuring ambient temperature, controlling coolant flow, and adjusting spindle speed are separate functions that involve different mechanisms or components within the machine. Thus, the precise feedback on position and speed provided by rotary encoders is fundamental to the operation and accuracy of CNC milling machines.