Effect of teeth modifications and gear-paired materials on vibration and acoustic characteristics of polymer gears

Abstract

Polymer gears (PGs) are increasingly replacing metal gears due to their benefits, such as reduced noise and vibration and no need for lubrication. However, they can suffer from heat accumulation, potentially leading to failure or shortened lifespan. Recent studies have focused on modifying polymer gear teeth to enhance durability and mitigate temperature-related failure. PG is favored in noise and vibration-sensitive applications, making it crucial to study how tooth modifications affect noise and vibration. By examining noise and vibration in PG, engineers can optimize gear designs to minimize unwanted noise and vibrations, improving product performance and user satisfaction. This study investigates the impact of teeth modifications, specifically polymer pinion with hole and polymer pinion with steel pin (PPSP), on vibration and acoustics compared to unmodified gears. These modified and unmodified gears are paired with polymer and metal gears, resulting in six combinations of gear pairs tested across various speeds and torque levels. The results show that PG paired with PP exhibits lower vibration and noise levels than when paired with metal gears. Among the modified gear pairs, the C-type gear pair (PPSP/PG) demonstrates the least vibration and noise, while the E-type gear pair (PPSP/SG) exhibits the highest. At maximum speed and torque, the C-type gear pair records an RMS value of 5.792 and a sound pressure level of 87.67 dBA. These findings can provide insights into optimizing gear performance through teeth modifications and benefiting the development of reliable and quieter gear systems. © 2023, The Author(s), under exclusive licence to The Brazilian Society of Mechanical Sciences and Engineering.