Improved Fuel Economy and Reliability for Cars
NSK Ltd. (NSK; Headquarters: Tokyo, Japan; President and CEO: Norio Otsuka) announced today that it has developed a high efficiency tapered roller bearing for automotive differential gears and transmissions that has approximately 30% less friction loss. NSK will launch this product in December and is targeting 2 billion yen in annual sales in 2016.
Tapered roller bearings are widely used in automobiles, particularly in locations that require a high level of support rigidity and that must withstand high levels of load. In order to improve fuel economy, the challenge is to find a way to reduce the friction loss of these bearings.
NSK responded to this challenge by leveraging its design knowhow to improve the efficiency of its tapered roller bearings and by utilizing the latest analysis techniques to develop the 4th generation of tapered roller bearing with greater efficiency.
1. Special crowning
By using a barrel shape referred to as special crowing for the guide surface of the inner and outer races, which can sustain a heavier load , and edge load can be reduced to realize less friction while maintaining the same or greater life and additional rigidity as compared to the conventional product.
2. Optimization of the internal design
NSK optimized the internal design by making changes to the number and length of the rollers and contact angle, etc. In doing so, friction loss was reduced by 30% and durability was improved by approximately 1.5 times, thereby making it possible to downsize even further.
NSK’s new tapered roller bearings can be used in a wide range of applications that requires a high level of support rigidity and to withstand heavy loads such as differential gears, manual and automatic transmissions for automobiles.
This bearing reduces friction loss by 30% compared to the conventional bearing, thereby contributing to improved fuel economy and extra life. Moreover, this bearing can also be used in areas that conventionally apply ball bearings.