August 31, 2006

NTN Develops Fixed Constant Velocity Joint (TUJ)
with Super High Operating Angle of 54 Degrees

World's Highest Operating Angle Ever for Automobile Drive shafts

The NTN Corporation (hereafter NTN) has succeeded in developing a fixed type constant velocity joint called a TUJ (Tapered track Undercut-free Joint) for automobile half shafts that has the world's highest maximum operating angle of 54 degrees. This joint will allow four-wheel drive (4WD) and front-wheel drive cars to achieve a large steering angle and a minimum turning radius.

The fixed type CVJ is used on the wheel end side of front-wheel drive and 4WD vehicles. Automotive customers have shown considerable effort to minimize the vehicle turning radius and extending the wheel base, thus driving demand for a fixed CVJ with a higher operating angle. The maximum operating angle in current market applications is 50 degrees for fixed type CVJ until now. NTN has achieved a maximum operating angle of 54 degrees by designing a ball track contour to achieve a longer ball track. CAE analysis was utilized to calculate generated loads to ensure an optimal design that equals the joint strength of existing CVJ products, even at the maximum operating angle

Therefore, NTN succeeded in designing an innovative CVJ with a 54 degree operating angle while still offering identical performance to our current high operating angle joints (UJ: max. operating angle 50 degrees). Expanding the operating angle by 4 degrees allows improvement of the minimum turning radius for typical mid-sized, front-wheel drive vehicles by approximately 70 centimeters (~13%). For the same minimum turning radius conditions, the wheel-base can be increased by about approximately 40 centimeters (~15%).

This new CVJ with its high operating angle effectively reduces the minimum turning radius and so will open up a new market segment targeting front-wheel drive and 4WD vehicles.

[Features]

Compared to conventional high angle fixed constant velocity joints (UJ: maximum operating angle 50 degrees), the NTN's new TUJ joint offers:
1. Maximum operating angle of 54 degrees
2. Identical performance (strength and endurance) and outer race dimensions

[TUJ (Tapered track Undercut-free Joint)]

[Advantages]

World's Highest Operating Angle Fixed CVJ (maximum angle of 54 degrees)

Fixed Constant Velocity Joint (CVJ) operating angle is improved by +4 degrees for typical application of mid-size, front wheel drive vehicles

Benefits -

•	Reduces vehicle minimum turning radius by approx 70 centimeters or 13 percent for an existing vehicle wheel base
•	Increases vehicle wheel base by approx 40 centimeters or 15 percent for the same minimum turning radius as existing product

[How it works]

• Track contour was changed to obtain greater ball track length