| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce rolling resistance and improve center wear resistance and pass-by noise. <P>SOLUTION: When an intersection between lines extended from a shoulder-side arc 21b and a side-part arc 21d is a reference point P, the following conditions are satisfied: 0.025×β+1.0≤θ≤0.045×β+2.5, wherein θ is an angle between a straight line A connecting the reference point and a center crown CC and a straight line B passing the center crown in a tire width direction, with respect to an aspect ratio β; 10≤Rc/Rs≤50, wherein Rc is a curvature radius Rc of a center-part arc 21a, and Rs is a curvature radius of the shoulder-side arc; 0.2≤L/(TDW/2)≤0.7, wherein L is a reference expansion width from a tire equatorial plane CL to an inner end of the shoulder-side arc in a tire width direction, and TDW is a tread expansion width; 12 [%]≤GR≤25 [%], wherein GR is a groove area ratio in a grounding region of a tread face; and GCR<GSR, wherein GCR is a groove area ratio in a center region of the tread face and GSR is a groove area ratio in a shoulder region of the tread face. <P>COPYRIGHT: (C)2012,JPO&INPIT |
