Gearbox Configuration Analysis

In the design of any new gearbox a conflict arises as to whether the gearbox should have an epicyclic or parallel shaft output stage. A method is derived which enables the relative merits of the two systems to be compared and the weight of each accurately predicted in the design stage. The method shows the actual relationship between the various gear design variables and the gear weight. A new factor called the configuration factor is identified which dominates the prediction of gearbox weight. It is shown how this factor is used to assess gearbox designs and identifies three features common to any low-weight gearbox. Finally combining these features in a semi- skeletal case results in an Advanced Engineering Gearbox, with a weight of only 62% of the current comparable gearbox.