Mechanisms Summary Notes

Summary of types of Mechanisms Mechanism Type Function of Mechanism Common Applications Rack and Pinion Conversion of Motion: Changes rotary motion to linear motion and vice versa. Car steering, tripod stands Ratchet and Pawl Control of Motion: Allows rotation in one direction while preventing it in the other. Fishing reels, winches Screw Conversion of Motion: Changes rotary motion into linear motion. Adjustable spanners, glue sticks Spring Loaded Control of Motion: Resists compressive, tensile, and torque forces. Retractable pens, trampolines Worm Gear Control of Motion: Controls speed and direction of rotation. Small electric motors, Venetian blinds Cranks Transmission of Motion: Transfers rotary motion to other components. Bicycle pedals, pencil sharpeners Crank & Slider Conversion of Motion: Changes rotary to reciprocal motion or vice versa. Car engines Cams Conversion of Motion: Changes circular motion to reciprocating or oscillating motion. Cam timers in car engines, automata toys Four Bar Linkage Conversion of Motion: Changes one type of motion to another based on link lengths. Pop-up books, car windscreen wipers Closed-Loop System Control of Motion: Uses feedback to control speed, direction, distance, and force. Thermostats, automatic doors

Summary of Motion Conversion Input Motion Output Motion Mechanism Linear Linear Simple Pulley, Compound Pulley Linear Reciprocating Levers Linear Rotary Rack and Pinion Linear Oscillating - Reciprocating Linear Levers Reciprocating Reciprocating Springs (for damping) Reciprocating Rotary Crank and Slider Reciprocating Oscillating - Rotary Linear Screw Mechanism, Rack and Pinion Rotary Reciprocating Crank and Slider Rotary Rotary Spur Gear, Bevel Gear, Step Pulley Rotary Oscillating Cam and Follower Oscillating Linear - Oscillating Reciprocating - Oscillating Rotary - Oscillating Oscillating Springs (for damping)