AbstractsEngineering

Face gear drives have found an important application in helicopter transmissions and also other transmission. An efficient and accurate design tool is desired to help in computer aided gear optimum design. This thesis work is part of developing such a design tool, Face Gear Load Distribution Program (LDP). The main contributions of the thesis work include constructing a valid face gear model for stress analysis and load distribution using a thin slice method, as well as conducting gear design optimization.In the thesis, a valid face gear model is established using the thin slice method to estimate compliance of the gear teeth. In order to obtain an accurate estimation for gear compliance, the coupling stiffness between of the adjacent slices is considered based on Borner’s method, in addition to the Boundary Element Method.Load distribution, tooth deflection, root stress, contact stress, flash temperature, and film thickness are analyzed and computed using the modified face gear LDP. The established face gear model is validated through comparing the results of the face gear LDP with those from the Contact Analysis Program Package (CAPP).Macro-geometry and Micro-geometry optimal design are also discussed in the thesis. A gear, active area to gear weight ratio, is defined as the objective to achieve higher load capacity for a lower weight design. Classical micro-geometry modification is used in the design to obtain low transmission error and desirable load distribution. In addition, a design example is given and the design procedure is presented.