Determination of Optimum Gear Ratios of Two-Stage Bevel Helical Gearboxes for Getting Minimum Gearbox Volume

The gear ratio is a main important factor that affects the size, the mass, the volume, and the cost of a gearbox. Therefore, in calculating and designing gearboxes, the determination of optimum gear ratios is of great interest. This paper introduces a study on determining optimum gear ratios of a two-stage bevel helical gearbox. To find the optimal gear ratios, a problem of optimizing the gearbox for getting the minimum gearbox volume was conducted. In this work, the influence of the input parameters, including the total gearbox ratio, the coefficient of the face width of the bevel and the helical gear sets, the allowable contact stress and the output torque and their interactions on the output, is evaluated. A simulation experiment was designed and conducted with the help of the Minitab R19 software. From the results of the work, regression models to find the optimum gear ratios were proposed.