| 摘要 |
PURPOSE:To improve stability of operation, by a method wherein a contour line on a meridional section of a tread molding surface is established by a specific general formula not having an inflection point. CONSTITUTION:A vulcanizing mold 1 is provided with a mold main body 3, which is provided with a recessed part 2 holding a green tire Ta, and at the time of vulcanization, the green tire to be held into the recessed part 2 is expanded by filling inner pressure, through which a tire T possessing an outside form fitting to an inner wall surface s of the recessed part 2 is formed. Then a contour line 5 in a meridional surface of a tread molding surface Sa molding a tread surface 21 of the tire T is established by a formula (aj is a coefficient) in coordinates where x and y axes are decided respectively in a tire axis direction outward and radial direction inward from a tire equatorial point. Since a curve y not having an inflection point indicated by the sum total of a 2i degree function (i=1,...n) is used like this, formation of a change point of a curvature in a state of a difference in level is removable. Therefore, in the tire formed by making use of the vulcanizing mold having the contour line like this, stable function of operation is improvable drastically. |
