Gearboxes used in electric vehicles are not only designed for high speeds and high torques – they are also very compact. This is not only true for the automotive sector, but also – and above all – for innovative types of applications such as e-bikes. These small but high-power and electrically driven gearboxes inspire design engineers to come up with more creative solutions. In many cases, they comprise small components with interfering contours, which pose new challenges for production. When it comes to the hard finishing of the gear teeth, the process-related potential goes hand in hand with high production costs. The most economical option is probably generating grinding. However, not all generating grinding machines are suitable for the production of the compact components. This article outlines the relevant demands and demonstrates possible solutions.
Gearbox performance, reliability, total cost of ownership (energy cost), overall impact on the environment, and anticipation of additional future regulations are top-of-mind issues in the industry. Optimization of the bearing set can significantly improve gearbox performance.
This method of testing large gearboxes or, indeed, any power transmission element, had numerous advantages and offers the possibility of large savings in time, energy, and plant, if the overall situation is conducive to its use. This usually requires that several such units need to be tested, and that they can be conveniently connected to each to each other in such a way as to form a closed-loop drive train. No power sink is required, and the drive input system has only to make up power losses. The level of circulating power is controlled by the torque, which is applied statically during rotation, and the drive speed. Principles, advantage, and limitations are described, together with recent experiences in the only known large-scale usage of this technique in Australia.