Cycloid reducer is an application planetary transmission principle, the use of novel cycloidal gear teeth meshing. Full cycloid gearing can be divided into three parts: input part, slow down some of the output section. The input shaft with a dislocation of 180 ° double eccentric, eccentric sleeve fitted in the two called jib roller bearings, forming H organizations, the center hole of two cycloidal rotor arm is the eccentric sleeve bearing raceway, cycloid with a group of ring gear needle arranged by needle teeth meshed to constitute a tooth for a tooth difference in the meshing of the reduction mechanism, (in order to reduce friction, the ratio of the small gear with the needle teeth needle sets of teeth).