Influence of the depth of relief on the meshing stiffness, load sharing, and transmission error of spur gears with wear

Abstract

In power transmission gears, the geometry of the contact surfaces influences the mesh stiffness and transmission error, which is source of dynamic load, noise, and vibration. Modifications in the geometry of the profiles, such as the tip relief to avoid the mesh-in impact or the wear that inevitably occurs in the sliding contact between friction surfaces, have therefore influence on the dynamic behaviour of the transmission. This paper presents a study of the influence of the depth of relief on the transmission error of spur gears with wear. The evolution of the peak-to-peak amplitude of transmission error, which determines the induced dynamic load, with the number of wear cycles, is analysed. The analysis considers depths of relief greater and smaller than the adjusted value for the elimination of the mesh-in impact, as well as symmetrical reliefs (at the beginning and end of contact) and asymmetrical (only at the end of contact), applied to standard and a high contact ratio spur gears.

The case of symmetric relief with optimal length of relief for minimum amplitude of transmission error is specifically analysed and the optimal depth of relief for minimum amplitude after a certain number of wear cycles is studied