A probabilistic approach to the design of gear trains

A probabilistic method is presented for the design of gear trains. By idealizing the gear train as a weakest-link kinematic chain, the design is made with respect to bending strength and surface wear resistance. The structural and the kinematic designs and the gear train are assumed to known. All the parameters affecting the design are considered as random variables. The design criterion is that the overall probability of failure of the gear drive in bending or by surface wear at nay particular speed of the output shaft must be equal to the given probability of failure. The design of a nine-speed lathe gear box has been considered as an example problem.