Explain the principle of the quick return mechanism of the shaper and what is the need of this mechanism?

The quick return mechanism is a feature of a shaper machine that allows the cutting tool to return quickly to its starting position after completing a cutting stroke. This mechanism is typically achieved through the use of a crank and slotted link mechanism, which converts the rotary motion of the machine's drive mechanism into the linear motion needed to move the cutting tool.

The need for a quick return mechanism in a shaper machine is to increase the efficiency and productivity of the machine. Without this mechanism, the cutting tool would have to return to its starting position at the same speed as it moved during the cutting stroke, which would significantly slow down the overall cutting process. By using a quick return mechanism, the cutting tool can return rapidly, allowing for faster cutting speeds and increased productivity.

Overall, the quick return mechanism is essential for ensuring that a shaper machine can operate efficiently and effectively, making it a crucial feature for any machining operation that requires precise and consistent cutting.