Pulleys can transmit power from one shaft to another to realize the operation of mechanical equipment. For example, automobile engines transmit power to generators, air-conditioning compressors and other equipment through pulleys to enable them to work normally. The pulley can adjust the transmission ratio by changing the size and number of tires, so as to realize the adjustment of the speed.

Spur gear is a kind of gear transmission mode, which consists of a pair of meshing gear teeth, both ends of the plane parallel and the gear teeth are arranged in a straight line.

Sprocket is a mechanical transmission device, mainly used to transmit power and rotary motion. It is composed of multiple gears, each gear has a certain number of teeth, and the teeth transmit motion through meshing. Sprockets are usually made of metal materials, which have high strength and wear resistance.

Tooth type: XL, L, H, XH.HTD, T, AT, straight edge tooth, involute