| 摘要 |
<p>An irregular-wear proof radialply tire is, for eliminating the irregular wearing at its shoulder portions, provided with a tread (5) comprising central portions (7) (7) each limited in a zone defined by W/2-0.365H (wherein W is a width, H is a height of the tire under its nominal inflation pressure) from the center line (1) of the tire, and shoulder portions (8) (8) which are each jointed to its associated central portion and liable to be subjected to the irregular wearing, said shoulder portions are formed with thick gum portions (9) (9) which are gradually thickened toward the shoulder edges. A mold (M) for fabricating the tire of this kind is provided with a tread-forming inner wall portion (5M) which is composed of two curved surfaces, one of which is a central zone-forming portion (7M) and another of which is a shoulder-forming portion (8M), the radius of the latter being larger than that of the former. A distance d between two curved surfaces each described along the radii, at the point of W/2 - O.2H (wherein W and H are the same as above) apart from the center line (1M) of the mold, is defined by; 0.4x 10-2H d 1.5 x 10-2H (wherein H is the same as above). The central portion (7) may be provided with continuous grooves extended along its circumferential direction. </p> |
