| 摘要 |
PURPOSE:To increase lateral rigidity of a pneumatic tire by forming a tire mold forming cavity in a shape expanded as going downward such that a radius at a part close to a tread forming surface is greater than the radius of curvature of a metal mold in the vicinity of the maximum width of a side wall forming surface and vulcanizing the tire in such a way that the radius becomes greater than the radius on the beat part side but smaller on the tread side. CONSTITUTION:This pneumatic tire is formed/vulcanized by means of the tire forming cavity of a tire vulcanizing metal mold whose shape is expanded as going downward, from a position where the sidewall forming surface of a toroidal tire forming cavity coming from a tread to a bead forming surface via a side wall, in such a manner that a ratio Rm2/Rm1, wherein Rme is a metal mold radius of curvature in an area below the side wall forming surface and Rm1 is a metal mold radius of curvature in an area above the side wall forming surface is larger than 1.1 but smaller than 1.5. In addition, under such condition that the specified maximum internal pressure is applied by 80%, the tire radius of curvature R12 in an area below the side wall part on more bead part side from the maximum width position of the side wall part is larger than Rm2 and the tire radius of curvature P11 in an area above the tread part side is smaller than Rm1.
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