Method for manufacturing tire
A method for manufacturing a tire includes forming a belt layer by bonding strip materials adjacent in the circumferential direction on the molding surface located on the outer circumferential side of the rigid core. Along the profile in the width direction of an outer circumferential surface of the rigid core, the rigid core is moved so that the molding surface is brought close to the strip material to be bonded, and the strip material is bonded to the molding surface extending in the longitudinal direction while rotating the rigid core in a direction in which the circumferential angle of the rigid core with respect to the longitudinal direction of the strip material changes, so that variation in the bonding margin, due to the position of the rigid core in the width direction, between strip materials that have been adjacently bonded to the molding surface in the circumferential direction is reduced.
1. A method for manufacturing a tire, comprising
sequentially bonding a large number of strip materials on a molding surface located on an outer circumferential side of a rigid core having an outer circumferential surface with a profile in which a circumferential length changes at a position in a width direction in a manner of extending the strip materials in a width direction of the rigid core at an inclined direction with respect to a circumferential direction of the rigid core, and arranging and bonding the strip materials in the circumferential direction, so that a belt layer is formed by bonding together the strip materials that are adjacently bonded in the circumferential direction;
forming a green tire having the belt layer; and
vulcanizing the green tire, wherein,
the profile of the rigid core is asymmetrical with respect to a center in the width direction,
the rigid core is relatively moved along the profile that is preliminarily known so that the molding surface is brought close to the strip material to be bonded to the molding surface,
the strip materials to be bonded are extended in the longitudinal direction and bonded to the molding surface while relatively turning the rigid core in a direction in which a circumferential angle with respect to the longitudinal direction of the strip materials to be bonded changes, so that variation in bonding margin, due to the position in the width of the rigid core, between the strip materials to be bonded adjacent to each other in the circumferential direction is reduced, and
after bonding the central portion in the longitudinal direction of the strip material to be bonded to the molding surface at a central portion of the rigid core in the width direction, the strip material to be bonded is bonded to the molding surface from the central portion in the longitudinal direction to one end in the longitudinal direction, then the strip material to be bonded is bonded to the molding surface from the central portion in the longitudinal direction to the other end in the longitudinal direction.
2. The method for manufacturing a tire according to claim 1 , wherein movement in the width direction of a portion of the strip material to be bonded in close proximity to that bonded to the molding surface is regulated by a guide which is disposed on both sides of the strip material in the width direction.