JTEKT
|
|
April 04, 2006
Development of tapered roller bearing with world's lowest friction torque
～Friction torque one-fifth that of conventional tapered roller bearings, lower than that of ball bearings～
|
|
In response to social demands for energy conservation and improved fuel efficiency, JTEKT Corporation has developed an original high-performance tapered roller bearing having 80% less rotational torque and 40% less size than conventional tapered roller bearings while also featuring long life and high rigidity.
Tapered roller bearings are preferred over ball bearings for application in such equipment as general industrial machinery, railway stock, automobiles, and construction equipment because of their superior rigidity and service life; however, their rotational torque is higher, and the growing social need for energy conservation has made reduction thereof a task of vital importance.
Utilizing design technology developed in-house and backed by testing as well all types of bearing-related theory, JTEKT, through optimizing such bearing internal dimensions as roller diameter and length as well as number of rollers, has succeeded in developing a tapered roller bearing with extremely low torque as well as both long life and high rigidity. Also, by clarifying the influence of bearing internal lubricant flow on torque and developing a new structure that optimally controls lubricant amount and flow, we were able to reduce agitation resistance significantly. Moreover, by means of original life-prolonging heat-treatment technology that optimizes bearing surface hardness and material microstructure, we were able to achieve a compact structure.
Through combining these innovative element technologies, JTEKT has succeeded in developing the Low Friction-Torque 3rd-Generation Tapered Roller Bearing (“LFT-III”), which shatters conventional concepts by possessing rotational torque lower even than that of double-row ball bearings. Additionally, we already have begun efforts to develop technology to further reduce rotational torque and expect to achieve a level of rotational torque 90% lower than that of conventional tapered roller bearings.
The LFT-III will enable vehicle differentials and drivetrains to be more compact and lightweight and have less friction loss, and they will contribute significantly to improvement of fuel efficiency (calculations indicate 2% fuel efficiency improvement and 3~5 g/km reduction of CO2 emissions). We plan to begin mass-production of LFT-III as automobile differential and drive pinion bearings at the end of 2007 and aim to achieve annual sales of six billion yen by 2010.
Our LFT-III was selected by the Japanese Society of Tribologists to receive a technology award for 2005. This award will be conferred at a ceremony to be held May 16. |
| |
| 【Product photo】 |
 |
 |
| |
|
| 【Conventional tapered roller bearing】 |
【LFT-III】 |
 |
 |
| |
|
| 【Performance】 |
|
| Bearing type |
Conventional bearing |
LFT-III |
Ball bearing |
| Structure |
 |
 |
 |
| Boundary dimensions(mm) |
ID45×OD115
×Width45 |
ID45×OD108
×Width32.5 |
ID45×OD135
×Width55 |
| Torque |
1 |
0.2 |
0.3 |
| Life |
In clean lubricant |
1 |
1 |
1 |
| In contaminated lubricant |
1 |
1 |
1 |
| Rigidity |
1 |
1 |
1 |
| Ease of assembly |
1 |
1 |
0.3 |
| Size |
1 |
0.6 |
1.8 |
| Mass(kg) |
2.5 |
1.4 |
4.1 |
|
|
|
|
|
COPYRIGHT 2006-2012 JTEKT CORPORATION. All Rights Reserved.
