Step-up or reduction gear series using internally meshing planetary gear structure

摘要

A series of transmission gears use an internally meshing planetary gear structure. The structure has a first shaft, eccentric bodies provided on the first shaft, and external gears mounted on the eccentric bodies through bearings. An internal gear internally meshes with the external gears, and a second shaft is connected to the external gears through means for transmitting only the rotational component of the external gears. The series includes a group of sub-series of the transmission gears, including transmission gears which are different from each other in a speed change ratio within a range from a low speed change ratio to a high speed change ratio, and which are the same in the mating dimension for installation to a mating machine. The transmission gears in the same sub-series include a type of transmission gears of a low angular backlash type which do not reduce the angular backlash. Each type of transmission gear has a same speed change ratio, a same mating dimension, and a same transmission capacity.