Cycloidal gear reducer is a novel transmission device that applies the principle of planetary transmission and adopts the meshing of cycloidal pin teeth. The entire transmission device of the cycloid reducer can be divided into three parts: input part, deceleration part, and output part. A double eccentric sleeve with a displacement of 180° is installed on the input shaft, and two roller bearings called swing arms are installed on the eccentric sleeve to form the H mechanism. The center holes of the two cycloids are the upper swing arm bearings of the eccentric sleeve. In order to reduce the friction, in a reducer with a small speed ratio, the cycloidal gear meshes with a set of circularly arranged needle teeth on the needle gear to form an internal meshing reduction mechanism with a tooth difference of one tooth. , Needle tooth sleeve is attached to the needle tooth).