Development of a Low-friction Motor using Bearings as Gear Teeth

In some of the areas in robotics, there are strong needs for compact reduction gearbox with high reduction ratios. Increasing the efficiency of such reduction gearboxes requires reducing the losses from the interdentation of the gears that are their principal component. Therefore, this paper proposes a novel gearbox with bearings used as the tooth surfaces. One important point of the proposal is to introduce the bearings only in the first stage of the reduction gearbox for reducing costs and backlash. The theoretical calculations show that a certain amount of friction is reduced by only introducing bearings in the first stage. The experimental results show that the friction was reduced, while there are big individual differences in the effect, owing to the limitation of machining accuracy.