Rao Jianhua

Department of Mechanical and

Electronic Engineering,

China University of Geosciences,

Wuhan 430074, China

Cao Weiqing

Liu Hongzhao

Department of Mechanical and

Instrument Engineering,

Xi’an University of Technology,

Xi’an 710048, China

Wang Dianhong

Department of Mechanical and

Electronic Engineering,

China University of Geosciences,

Wuhan 430074 China

Abstract: According to the characteristics of gear trains, tri-color-graph is introduced to describe to the structure. Further more tri-color-tree is proposed to describe structure characteristics of gear trains. Concepts, such as parent array, leaf couple array, and leaf couple parent array, are defined to express digitally the structure of gear trains. A new method of type synthesis of gear trains is presented. The key of the method is to develop the higher class of gear trains by adding basic structure chain to the original train. This method is effective and is easy to perform with computer.