The effect of gating and material on measured transmission error and noise of injection molded gears

摘要

The use of plastic gears is expanding in many different markets. Their application is cost -effective when produced on a large scale using a net-shape process such as injection molding. However, variables in the molding process have a direct impact on final gear geometry. In this paper gears molded out of three different polymeric materials using three different gating configurations are used to show the effect of gating on runout, transmission error, and noise. The runout characteristics directly affect long-term transmission error and act to create side banding about the mesh harmonics in the frequency spectrum in both transmission error and noise signals. Additionally, load and speed effects on the gear noise are verified, and gear noise levels for different materials are compared.