The movement and power between the two parallel shafts are transmitted by the meshing between the chain sprockets. It is a forced transmission with meshing properties. Among them, roller chain transmission is widely used. In chain transmission, according to the chain structure The main differences are roller chain transmission and toothed chain transmission. When chain transmission works, the rollers on the sleeve roll along the sprocket tooth profile, which can reduce the wear of the chain and sprocket tooth.

Parallel more than one single-row chain, a chain connected by a long pin shaft is a multi-row chain. The more rows of the chain, the higher the load-bearing capacity. However, the manufacturing and installation requirements of the chain will be relatively higher. It is good to reduce the service life of multi-row chains, so the number of rows should not exceed 4 rows. When the transmission power is relatively large, two or more double-row chains or three-row chains can be used.

When the number of chain links is even, its shape is the same as that of the chain links. At the joint, the pin and the link plate are fixed with a wire lock pin or a spring card. When the number of chain links is odd, it needs to be added. A transition link.