Press Release

NSK Develops Ultra High-speed Ball Bearings for Motors and Power Generators in Next Generation Hybrid Vehicles

Reduced friction enables 50% faster, ultra high-speed rotation

Tokyo, Japan, October 15, 2009 – NSK Ltd. (NSK; Headquarters: Tokyo, Japan; President and CEO: Norio Otsuka) has developed ball bearings that enable ultra high-speed rotation by greatly reducing friction. The new product will contribute to better fuel economy in next generation hybrid vehicles by facilitating ultra high-speed rotation in motors and power generators.

Ultra High-speed Ball Bearings for Motors and Power Generators in Next Generation Hybrid Vehicles

Auto manufacturers have a growing need for ultra high-speed rotation technologies to secure output power while they continue scaling down the size and weight of drive motors and power generators in order to improve fuel economy in next-generation hybrid systems.
NSK's new ball bearings, which are for use in motors and power generators in next-generation hybrid vehicles, will deliver ultra high-speed rotation of at least 30,000 revolutions per minute, 50% faster than conventional bearings. The product facilitates miniaturization of next generation hybrid systems while enabling ultra high-speeds in drive motors and power generators.
NSK designed the new product to improve fuel economy in compact to full-size next-generation hybrid vehicles, and expects annual sales of 2 billion yen for this product by 2015.
The new product will be exhibited at the 41st Tokyo Motor Show 2009 to be held at the Makuhari Messe International Convention Complex in the city of Chiba from Wednesday, October 21 to Wednesday November 4*.

* General admission is from Saturday, October 24 to Wednesday, November 4

Product features

Improved lubrication
A plate to control the flow rate of lubricants was installed at the lubricant port of the bearing module. The plate ensures oil is supplied to the inner ring, where lubrication tends to become depleted easily in an environment where tremendous centrifugal force is generated during ultra high-speed rotation, thereby reducing friction-generated heat.
Reduced friction
Optimized ball diameter and groove dimensions inside the bearing module control friction and heat even under ultra high-speed rotation, preventing seizing. Cage vibration is dampened by adjusting the gap between the cage and the balls and inner ring, thereby reducing wear at contact points.
Greater durability
The annular part of the cage was thickened and the cage strength increased to prevent deformation by the centrifugal force applied to the cage during ultra high-speed rotation of the bearings.