The design of NN type planetary gear reducer for servo motor

The servo motor is widely used in the numerical control system, in order to reduce speed and increase torque, reducer with small volume and large transmission ratio is needed.Planetary gear reducer with two internal gear pairs is known as NN type reducer,it has the advantage of small volume and large transmission ratio so that it is a very suitable selection. This paper takes the reducer design with large transmission ratio (100) as an example, introduces the key technique of the design for NN type reducer, such as the choice of the tooth number, the calculation of the internal meshing gear pairs and the design of the balance structure, provides a clear train of thought and some efficient design method.