NSK has developed a third-gen ultra-high-speed ball bearing for EV motors, which the company says is capable of operating at more than 1.8 million dmN (a measure of bearing rotational performance).
The new bearing is claimed by NSK to be the fastest grease-lubricated deep-groove ball bearing in the world for electric vehicles. It has been developed to extend vehicle range and achieve higher energy economy while enabling the downsizing of components such as electric motors to improve interior space. The lighter components aid in improving range while higher-output motors improve the efficiency of such vehicles.
With the previous iteration of bearings offering 1.4 million dmN, the improvements to the product enable it to be used in components with much higher speeds.
Alongside the 28.5% increase in rotational performance, the bearing features what is claimed to be the world’s first cage design, which leverages the benefits of topology optimization. This enables the optimization of material layout within the design space to maximize the strength and minimize the weight of the bearing by eliminating material that does not contribute to the cage’s durability or rigidity. NSK reduced the development time for the cage by utilizing simulation technology during the R&D stage to verify performance and production.
Produced using a new, high-rigidity resin material, the cage is also said to be more effective at suppressing deformation during high-speed operations than traditionally used materials. The bearing is then filled with a proprietary grease to reduce the chance of lubricant churning and heat generation that might result in component failure.