NASA Goddard Space Flight Center developed gear bearing technology that combines gear and bearing functions into a single unit that significantly improves gear drives for electrical, internal combustion, and turbine motors. The gear bearing design incorporates rifle-true anti-backlash, improved thrust bearing performance, and phase-tuning techniques for superior low-speed reduction. Because it combines gear and bearing functions, it reduces weight, number of parts, size, and cost, while also increasing load capacity and performance.

Photo (left) and line drawings (right) of gear bearings.

The gear bearings provide superior speed reduction in a small package. They form rolling friction systems that function both as gears and bearings, and are compatible with most gear types including spur, helical, elliptical, and bevel gears. These self-synchronized components can be in the form of planets, sun, rings, racks, and segments thereof. The design reduces micro-chatter and eliminates rotational wobble to create smooth and precise control. It offers tighter mesh, more even gear loading, and reduced friction and wear.

Gear bearings eliminate separate bearings, inner races, and carriers, as well as intermediate members between gears and bearings. Load paths go directly from one gear bearing component to another and then to ground. By incorporating helical gear teeth forms (including herringbone), gear bearings provide outstanding thrust bearing performance. They also provide high- and low-speed reduction through the incorporation of phase tuning. Phase tuning allows differentiation in the number of teeth that must be engaged between input and output rings in a planetary gearset, enabling successful reduction ratios of 2:1 to 2,000:1.

NASA is actively seeking licensees to commercialize this technology. For more information, contact the Goddard Strategic Partnerships Office at This email address is being protected from spambots. You need JavaScript enabled to view it. or 301-286-5810. Follow this link here for more information.