gearwheels

Gearwheels, also known as gears, are toothed wheels that engage with others to transmit torque and motion. They are fundamental components in mechanical systems, used to alter speed, direction, or torque of a rotating shaft. Gears work by meshing their teeth, where the teeth of one gear catch the teeth of another, causing the second gear to rotate. The ratio of the number of teeth on two meshing gears determines the speed and torque ratio between them. A smaller gear driving a larger gear will result in a lower speed but higher torque at the larger gear, and vice versa.

There are several common types of gearwheels, each suited for different applications. Spur gears are the simplest, with teeth cut parallel to the axis of rotation. Bevel gears are used to transmit motion between shafts that intersect at an angle, often 90 degrees. Worm gears consist of a screw-like shaft (worm) that meshes with a toothed wheel (worm wheel), providing significant speed reduction and high torque multiplication. Helical gears have teeth cut at an angle to the axis, allowing for smoother and quieter operation than spur gears, and can transmit motion between parallel shafts. Rack and pinion gears convert rotational motion to linear motion, with a toothed wheel (pinion) engaging with a linear toothed bar (rack).

The design and manufacturing of gearwheels require precision to ensure proper engagement and minimize wear. Materials used can range from metals like steel and brass to plastics and composites, depending on the required strength, durability, and operating environment. Gears are ubiquitous in machinery, found in everything from clocks and automotive transmissions to industrial equipment and robotics.