The split torque gearbox is a practical solution to the transmission of high torques with the lowest possible weight. In this article, we perform the mathematics necessary to calculate possible solutions for the simultaneous meshing of four wheels on the basis of geometric conditioning factors. These calculations will be illustrated by numerical applications. Finally, particular cases of planetary gearboxes and a gearbox with equal idler pinions are studied, with the conclusion that their application is appropriate in specific conditions.

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