May 13, 2003

Delivery of Third-generation Hub Bearings with Brake Rotor Commences

Background to Development

In third-generation hub bearings, the wheel and brake rotor are attached to the hub flange. However, large rotation runout of the brake rotor can cause shudder when braking. Although car manufacturers adjust rotation runout during rotor assembly to control shudder, the Third-generation Hub Bearing with Brake Rotor was developed in response to a demand for improved driving comfort and even further reduction of vibrations.

In the Third-generation Hub Bearing with Brake Rotor, the rotor braking surfaces are cut after the rotor has been attached to the third-generation hub bearing. This results in higher running accuracy. Delivery to automotive manufacturers in North America commenced from this year and we expect significant market expansion due to its improved running accuracy and simpler assembly.

Main Product Features

1. Rotation runout and machining error for the rotor installation surface have been eliminated by machining the rotor surface while driving the hub bearing in rotation. Vibration of both rotor surfaces has been reduced to less than 30μm, half that of conventional third-generation hub bearings.
2. The need to adjust rotation runout during rotor assembly has been eliminated by machining the brake rotor after it has been attached to the hub bearing and supplying it as a single unit.

Production and Sales

The Third-generation Hub Bearing with Brake Rotor is being manufactured at the Elgin Plant in Illinois, U.S.A. Our annual sales target is 2 billion yen.