Which mechanism produces intermittent rotary motion from continuous rotary motion?

• A. Whitworth Mechanism
• B. Scotch Yoke Mechanism
• C. Geneva Mechanism
• D. Elliptical trammel

Answer: (C)

The Geneva Mechanism is designed specifically to convert continuous rotary motion into intermittent rotary motion, making it widely used in applications such as film projectors, clockworks, and other machinery where a precise stop-and-go motion is required. The mechanism involves a drive wheel with a pin that engages sequentially with slots in a Geneva wheel. As the drive wheel rotates, the pin moves through a slot, advancing the Geneva wheel by one increment before it locks in place. This allows for a distinct and controlled movement, creating a series of short, discrete motions from a continuous source of motion. Thus, the Geneva Mechanism is the ideal choice for applications that require a stepwise rotation.

The Whitworth Mechanism and Scotch Yoke Mechanism both facilitate linear motion conversion and have different modes of operation. The Elliptical trammel produces a specific type of curved motion rather than controlling intermittent rotation effectively. Therefore, the Geneva Mechanism stands out as the correct answer for producing intermittent rotary motion from continuous rotary motion.