A simplified model for wear prediction in helical gears

A simplified model for wear simulation of helical gears is developed. A helical wheel is treated in the model as several thin independent spur gear teeth with a common central axis and gradually turned relative each other a small angle corresponding to the helix angle. The load distribution along a tooth flank varies depending on the stiffness of a tooth. The tooth stiffness is determined with an empirical model developed by Simon [J. Mech., Transm. Automat. Design 110 (1988) 197]. The tooth deformation and the deviation from ideal involute form due to profile modification and wear also influences the load distribution. The wear model used is a modified Archard’s wear model and the basic principle used is the so-called “single point observation principle”, which means that the conditions at individual points on the gear flanks are observed during operation. The pressure in a contact is in this simple model assumed to be constant and equal to the Hertzian mean pressure. The sliding distance, a point on a flank slide against the interacting surface during a working cycle is determined by analytical expressions previously used for spur gears. Simulation results with the simplified model are compared with corresponding results from a previously made simulation with a more extensive model.