| 摘要 |
PROBLEM TO BE SOLVED: To considerably suppress generation of a pinch cut, while suppressing an increase of weight. SOLUTION: This run-flat tire includes a side reinforcing rubber layer 9 arranged in an inside face of a carcass 6 and a sidewall part to have a substantially crescent shape in cross section. A bead part 4 is provided with a rim protector 11 projecting to the tire shaft direction outside to cover the tire radial direction outside of a rim flange JF and extending in a tire peripheral direction. In a meridian cross section of a regular state, a carcass maximum width point M of the carcass 6 is located at the tire shaft direction inside by 0.5 to 4.0 mm from a rim separation point F which is the outermost tire shaft direction outside point where the rim protector 11 is in contact with the rim flange JF, in a run-flat state in which internal pressure is made zero and regular load is loaded. An aramid fiber cord is used for a carcass cord. A twist coefficient T (T=N×√ä(0.125×D/2)/ρ}×10<SP>-3</SP>) of the aramid fiber cord is in the range of 0.5 to 0.7, wherein N is the first-twist number (times/10 cm), D is total display dicitex (fineness), andρis a specific gravity of a cord material. COPYRIGHT: (C)2010,JPO&INPIT |
