Silicon retainer ring integration in micro-turbine with thrust ball bearing support mechanism

This work demonstrates the first integration of a microfabricated silicon retainer ring packaged within a silicon micro turbine (SMT) employing a thrust micro ball bearing. Retainer rings, common in macro-scale ball bearings, provide uniform spacing between the balls and reduce the number of balls required for stable operation. Previous work on integrated silicon retainer rings for radial micro ball bearings has shown stable operation, and microfabricated thrust ball bearings have been demonstrated as viable support systems for micro-pumps and -motors. In this work several retainer ring designs are implemented within thrust-oriented ball bearings, showing stable and repeatable operation in testing for over 500,000 revolutions.