A study on the design of asymmetric spur gears in gear pump applications

Abstract

This paper presents a study on the design of spur gears with asymmetric teeth in external gear pump applications. A model is generated for asymmetric gears and the instantaneous flowrate equation is derived. The process of generating the gear model and the flowrate calculations are automated with a computer program developed in this study. Using the data from the model, tooth contact and root bending stresses are evaluated during a mesh cycle by finite element analyses. Seventeen different spur gear pair designs are tested for different drive side pressure angle, coast side pressure angle and profile shift coefficients. The effects of these parameters on tooth contact stress, bending stress, flowrate and flowrate fluctuation have been investigated for a specific gear pump.