| 摘要 |
PURPOSE:To prevent an maldistribution of the ground pressure of a tread land part at the acting time of side force. CONSTITUTION:Tread land parts 22 divided by main grooves 14 and lug grooves 20 are divided and separated in central parts 26 and outer circumferential parts 28 by narrow grooves 24. The ground contact area of central parts 26 is set at 50 percent of the ground contact area of outer circumferential parts 28. Central parts 26 are projected from outer circumferential parts 28 in the form of large spherical surface, and the projecting dimension from outer circumferential parts 28 is set to 0.2mm at central parts. The dimensions of narrow grooves 24 are set to 3mm deep and 0.5mm wide. When tread land parts 22 make contact with a road surface, the ground pressure acting upon tread land parts 22 becomes high in the vicinity of central parts 26 and low in the vicinity of outer circumferential parts 28. When side force acts upon the tire, the ground pressure on the end parts of tread ground parts 22 on the side wherefrom the side force comes in rises, and by shift of the ground pressure closer to that in the vicinity of central parts 26, the ground pressure of tread land parts 22 is nearly equalized. |
