MRO Magazine

NSK develops the world’s thinnest microactuator pivot ball bearing assembly

Ann Arbor, MI -- NSK Corporation has developed the world's thinnest microactuator pivot ball bearing assembly. At j...


September 26, 2006
By MRO Magazine

Ann Arbor, MI — NSK Corporation has developed the world’s thinnest microactuator pivot ball bearing assembly. At just 1.83 mm in height, it is a full 25% thinner than its predecessor and is designed for use as the support mechanism of the head that reads and writes information on discs in an ultra-thin 2.5 mm hard disk drive (HDD). Thinner than a flash memory-type media CF card, the ultra-thin 2.5 mm HDD possesses a larger storage capacity.

Reducing the thickness of the assembly was not the only requirement. It also needed to offer improved impact resistance and reduced friction. A critical component of NSK’s success lay in the design and manufacture of the bearing cage itself. By moulding the cage from resin reinforced with nano-scale fibres, it was possible to create a cage wall that was a mere 0.1 mm thick. With the cage wall reduced to such an incredibly thin layer without sacrificing its structural integrity, engineers were able to maximize the steel ball size in the bearing, which improved impact resistance by 25%.

Furthermore, the advanced cage design and materials, in conjunction with advances in process and assembly technology, also translated into lower torque and reduced friction when compared to a conventional steel cage.

“We are very excited by this latest development,” observed Tom Rouse, president of NSK. “It not only offers the disc drive industry tremendous advantages, it also underscores NSK’s position as an innovation and technology leader.”


Headquartered in Tokyo, Japan, NSK Limited is a world-class producer and innovator of motion and control products. It is the world’s second largest bearing manufacturer, employs over 20,000 people worldwide, has more than 47 global manufacturing facilities and over 100 sales operations, operates 13 technology centres and produces and distributes over 100,000 different types of bearings, linear motion and automotive component products.

For more information, contact NSK Canada, Mississauga, Ont.