Abstract
Tire inventions are classified to three categories; change of material, change of construction, change of manufacturing. The steel belted radial tire is one of the examples where three changes occurred at the same time. Since steel belted radial tire enabled us to design sidewall and crown independently, the design freedoms were increased. This is related with the concept of function separation. In order to satisfy the demands of customer, we cannot solve them by only tire design anymore. Hence, vehicle, road and tire industries related with the mobility need to solve them together by following function separation principle. This approach requires the fine-tuned integration which is the strength of Japanese industry. For example, the rolling resistance will be improved by a tire with a new construction and higher inner pressure. The deteriorated riding comfort will be compensated by the suspension, and the deteriorated brake distance will be improved by ITS (Intelligent Transport Systems).
