Patent ID: 7862674

Claim:
A forming method for forming an assembly of a bead core and an apex rubber, the assembly comprising the bead core, and the apex rubber arranged on a radially outer peripheral surface of the bead core and having a triangular cross sectional shape, comprising the steps of: using a rotating body comprising a rotating base portion having an assembly forming surface, and a core receiving portion having a receiving surface supporting the radially inner peripheral surface of the bead core, and projecting from said rotating base portion in the axially outward direction of said rotating base portion, the assembly forming surface being constituted by one side surface in an axial direction of the rotating base portion and extending radially outward from the receiving surface; and forming the apex rubber by winding a rubber strip along the assembly forming surface from a base rubber set on the radially outer peripheral surface of the bead core supported on the receiving surface, said rubber strip made of an unvulcanized rubber and having a strip width (Wg) between 5 and 20 mm and a strip thickness (Tg) between 0.5 and 2.0 mm, wherein said base rubber has an L-shaped cross sectional shape provided with a bottom surface brought into contact with the radially outer peripheral surface of the bead core, a rising surface brought into contact with the assembly forming surface so as to be orthogonal to the bottom surface, and a connection surface corresponding to an L-shaped surface joining the bottom surface and the rising surface, a height in the radial direction of the rising surface being equal to or more than 50% of the width (W 2 ) in the tire axial direction of the bottom surface, and wherein the rubber strip is spirally wound to an outer side in the radial direction from the connection surface of the base rubber along the assembly forming surface so as to laminate in a tapered cross sectional shape.