cogwheels

Cogwheels are cylindrical gears with teeth around their circumference that mesh with another gear to transmit torque and rotate shafts. They vary in size, tooth count, and tooth form depending on the application.

When two cogwheels mesh, torque transmission is determined by the gear ratio, equal to the inverse of the number of teeth on each gear. The direction of rotation reverses. The pitch circle defines spacing, and the module or diametral pitch sets tooth size.

Common types include spur gears with straight teeth; helical gears with angled teeth for smoother operation; bevel gears for intersecting shafts; internal gears where teeth face inward; and rack and pinion, which converts rotary motion to linear motion.

Cogwheels are made from steel, cast iron, bronze, or engineered plastics. Manufacturing methods include hobbing, milling, and gear shaping, as well as casting or forging for blanks. Sizing uses metric module or inch diametral pitch, with standardization by ISO, AGMA, and DIN.

Cogwheels are used in clocks, automobiles, industrial machinery, robotics, and consumer devices. Their efficiency depends on lubrication, material quality, alignment, and backlash control. Regular maintenance includes inspecting wear, noise, and ensuring proper lubrication and adequate cooling.