MANUFACTURING METHOD FOR CORE MEMBER

PROBLEM TO BE SOLVED: To provide a manufacturing method for a core member capable of suppressing a winding failure.SOLUTION: A manufacturing method for a core member 25 for a tire comprises: an upward winding step in which a bead wire 22 is wound from one side to the other side in an axial direction while inclining toward outside from radially inside; and a downward winding step in which a bead wire 22 is wound from the other side to the one side in the axial direction while inclining toward inside from radially outside. Tension applied to the bead wire 22 in the downward winding step is smaller than tension applied to the bead wire 22 in the upward winding step. Preferably, downward pressing force with which a tension roller is pressed against the bead wire 22 in the downward winding step is smaller than upward pressing force with which the tension roller is pressed against the bead wire 22 in the upward winding step.SELECTED DRAWING: Figure 4 【課題】巻き崩れを抑制しうるコア部材の製造方法の提供。【解決手段】タイヤのコア部材２５の製造方法は、軸方向一方から他方に向かって半径方向内側から外側向きに傾斜してビードワイヤ２２が巻回される上り巻回工程と、軸方向他方から一方に向かって半径方向外側から内側向きに傾斜してビードワイヤ２２が巻回される下り巻回工程とを備えている。下り巻回工程においてビードワイヤ２２に付加される張力は、上り巻回工程においてビードワイヤ２２に付加される張力より小さい。好ましくは、下り巻回工程でテンションローラがビードワイヤ２２に押し付けられる下り押し付け力が、上り巻回工程でテンションローラがビードワイヤ２２に押し付けられる上り押し付け力より小さい。【選択図】図４