To rapidly enable the control of the ground contact state of a pneumatic tire.
In the pneumatic tire, an auxiliary air chamber 26 is formed in both shoulder ribs 28 outside a belt. By changing the pressure of the auxiliary air chamber 26, the ground contact state, in other words, the ground contact pressure, the ground contact length and the ground contact shape can be changed, or the pseudo camber angle can be changed. The auxiliary air chamber 26 is arranged inside a tread 16 outside the belt, and the width AQ of the auxiliary air chamber 26 is set in a range of ≥5% and <50% of the ground contact width TW. Thus, the volume of the pneumatic tire is relatively and sufficiently small with respect to a tire air chamber 11 formed between the pneumatic tire 10 and a rim wheel 12, The internal pressure (the volume) of the auxiliary air chamber 26 can be rapidly changed according to the state of a vehicle even in a traveling mode by taking out/putting in a gas of the small amount.
Kato Kazunori
Katsuichi Nishimoto
Hiroshi Fukuda