Running performance of tandem stages traction drive modified from angular contact ball bearings

Micro-Traction-Drives are made from modified angular-contact ball bearings. It was developed for its small size and transmission of high torque. The structure of a Micro-Traction-Drive is as follows: The traction force is generated by the thrust preload between the inner race and the outer race. The retainer that is connected to the output shaft transmits the driving torque. The retainer is made of copper alloy. Test-runs of the Micro-Traction-Drive have been carried out as the tandem stage type (reduction ratio: 7.3). Results from testing show that a Micro-Traction-Drive has been successfully operated at 20,000 rpm. Furthermore, the output shaft torque, volume of the preload of a Micro-Traction-Drive, and number of balls were examined, resulting in a design manual of the Micro-Traction-Drive.