Mechanical efficiency of a planetary-gear-train type automatic transmission

摘要

Planetary gear trains have the advantage of compactness, light weight, high speed reduction and capability of differential drive, so they are often used in transmission systems. The purpose of this paper is to propose a systematic methodology for the analysis of the mechanical efficiency of a planetary-gear-train type automatic transmission. Based on the Graph theory, a canonical graph representation of the kinematic structure of planetary-gear-train type automatic transmission is presented. Then, the equations of the mechanical efficiency of the planetary-gear-train type automatic transmission have been constructed. The design of an automatic transmission for the automobile is used as an example to illustrate the proposed methodology. The results of the paper provide a powerful tool for the design of the planetary-gear-train type automatic transmissions.