A crank handle is a fundamental mechanical device prevalent in engineering, consisting of an arm attached at a right angle to a rotating shaft. When the handle is turned, it induces the shaft to rotate, translating manual labor into rotational motion. This mechanism is employed in diverse engineering applications, from operating hand drills to adjusting components on lathes, and in marine environments where they may be used for boat winches or for manually operating certain valves and equipment on ships.
These handles can be constructed from a variety of materials, including stainless steel, steel, and glass-reinforced plastic, each offering distinct advantages based on the specific application and environment. The crank handle's design facilitates the application of leverage, efficiently producing circular motion to drive other machinery components.