Wälzlager - 2012-01-30
NSK Ltd. 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.
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 extreme high speed rotation over 30,000 revolutions per minute, 50% faster than conventional bearings. The product facilitates miniaturisation of next generation hybrid systems while enabling these high speeds in drive motors and power generators.
1. 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.
2. Reduced friction
Optimised 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, balls and inner ring, thereby reducing wear at contact points.
3. Greater durability
The annular part of the cage was thickened and the cage strengthened to prevent deformation by the centrifugal force applied to the cage during extreme high-speed rotation of the bearings.