Patent ID: 7208061
Filing Date: 2007-04-24
Classification: B29D

Abstract:
1. A method for producing a raw tire comprising: a grasping step for grasping a tread ring including a belt ply and a tread rubber by a grasping tool comprising a plurality of segments and provided in an annular base body which is able to move concentrically with a former in the axial direction of the tire, a step for forming a cylindrical raw tire base body by assembling tire members including a carcass ply on the former, a positioning step for positioning the grasped tread ring with respect to the raw tire base body on the former by relative movement between the annular base body and the former, an expanding step for pushing and pasting the raw tire base body to and against a central portion of the grasped tread ring by expanding the raw tire base body on the former from its cylindrical shape into its toroidal shape by applying an internal pressure to the cylindrical raw tire base body, and a pasting step for pasting the inner peripheral surface of the tread ring to the outer peripheral surface of the toroidal raw tire base body by expanding annular rubber tube bodies extending in the circumferential direction of the tire which are disposed on each side of the grasping tool by application of an internal pressure to the rubber tube bodies, thereby pushing down shoulder side portions of the tread ring so as to paste the tread ring to the toroidal raw tire base body by direct contact with the expanded annular rubber tube bodies, wherein each of the annular rubber tube bodies is attached to the annular base body with play so as to be able to deviate in position, and each of the annular rubber tube bodies has a substantially circular cross section having a diameter of 25 to 100% of the tread width of the tread ring when an inner pressure of 1 atm is applied thereto.