Stair chain

The utility model discloses a stair chain contains link in a plurality of, is connected through a pair of outer chain plate between the link in two, and the link contains a pair of gyro wheel in every, is equipped with a pivot on every gyro wheel, is connected through a pair of inner plate between two pivots, still is equipped with a metal sleeve in the gyro wheel, and the metal sleeve cup joints in the pivot, still is equipped with a pair of retaining ring in the pivot, the retaining ring is located between gyro wheel and the inner plate. The utility model discloses a stair chain is formed through outer chain plate built -up connection by interior link, chains the pivot that contains two gyro wheels and match with it in every, has set up a metal sleeve between gyro wheel and pivot, still is equipped with a pair of retaining ring between gyro wheel and the inner plate to reduce the body wearing and tearing of gyro wheel greatly, prolonged stair chain's life. 本实用新型公开了种梯级链条，包含多个内链结，两个内链结间通过对外链板相连接，每个内链结包含对滚轮，每个