Application of high performance polymer gears in light urban electric vehicle powertrains

Abstract

AbstractThe application of high-performance polymer gears in power transmissions is increasingly gaining focus in current research and industrial practice. The well-known advantages of thermoplastics such as cost-efficient production and low density compete with moderate strength and limited operating temperatures. However, the properties of thermoplastics can be used effectively to address the challenges of more efficient powertrains with higher power density, reduced fuel consumption, and reduced manufacturing costs. This work focuses on the implementation of high-performance polymer gears in the powertrain of a light electric vehicle. For demonstration purposes, a series transmission of a prototype of a light electric vehicle is modified and investigated considering the specific properties of polymers and steel materials. Due to its material properties, the high-performance polymer VESTAKEEP® 5000 G was used for the investigations. Different constructional modifications to the serial transmission as well as modifications of the micro geometry of the gears were applied to improve the load distribution and provide sufficient load carrying capacity to the polymer gears. Assuming usual driving cycles and lifetime, the calculations according to VDI 2736 [1] and RIKOR [2] indicate a sufficient load-carrying capacity for the polymer gears used inside. Under the given assumptions, the use of polymer gears in a powertrain of light electric vehicles appears to be possible.