NSK Ltd. (NSK; Headquarters: Tokyo, Japan; President and CEO: Toshihiro Uchiyama) today announced that it has developed a new bearing with high-speed capability and excellent sealing performance for use in automotive belt idlers and tensioner pulleys.
By improving the traditional seal, the new product delivers both durability at high speeds and excellent sealing performance. This product contributes to greater automobile reliability in markets with harsh driving environments. NSK is targeting 1 billion yen in global sales of this product in 2020.
Idler: |
This part enables universal adjustment for the wrap angle and layout of the front engine accessory drive (FEAD) belt. |
Tensioner: |
This part keeps the constant tension in the FEAD belt. |
In recent years across the globe, automotive engines have become more compact to increase fuel efficiency. To meet this trend, bearings for idlers and tensioners are required to support high-speed revolutions to work with smaller pulleys.
On the other hand, the demand for automobiles is increasing in developing markets. Often the conditions in these regions are severe for automobiles, where a great deal of water and dust can enter the engine compartment. The idler and tensioner pulleys are located in the front of the engine compartment. Because of this, bearings for idlers and tensioners must have excellent sealing performance.
Traditional high-speed seals were designed with a shape that reduced the effects of the centrifugal force. However, their highly rigid shape caused significant reaction force fluctuations, which could generate gaps in the seal lip.
By designing a flexible seal lip on the traditional high-performance seal, NSK enhanced follow-ability and improved seal performance. However, the high-speed revolutions caused significant reaction force fluctuations, raising concerns about seal lip damage.
NSK has now developed a new bearing with excellent sealing performance and high-speed capability for idler and tensioner applications by optimizing the shape of the seal lip.