Method of building carcass band and stitcher apparatus

A method of forming a carcass band for forming a tire, comprising:

• pasting a carcass ply sheet onto a rubber sheet member that is wound around a building drum;
• then,
• pressing the carcass ply sheet from its outer periphery using a stitcher apparatus comprising
• a plurality of pressure-bond rollers having elasticity and a cylindrical shape, each of which having a roller axis tangential to a circle line that is concentric to and larger than the building drum,
• a plurality of supporting mechanisms for advancing and retreating each supporting one of the pressure-bond rollers so as to be movable in diametrical direction, wherein the pressure-bond rollers are arrayed, in a plurality of rows, throughout an entire range of the circle line by a constant pitch in circumferential direction, and the supporting mechanisms comprises a plurality of air cylinders capable of permitting displacement in diametrical direction following recessed and projected shape of a pressed surface,
• wherein the building drum is placed inside of the circle line, and the building drum is moved in axial direction relative to the pressure-bond rollers inside a circular array of the pressure-bond rollers during the pressing step, and
• wherein, when the building drum is moved in the axial direction relative to the pressure-bond rollers, the pressure-bond rollers are moved inward in a diameter direction such that the inscribed circle diameter of the pressure-bond rollers in the circular array is made to be smaller than the outer diameter of the carcass ply sheet on the building drum, and whole periphery of the carcass ply sheet is pressed to be bonded simultaneously by the pressure-bond rollers with a preset pressure,
• wherein the carcass ply sheet is pressed by the pressure-bond rollers to pressure-bond from a center portion in a width direction over to a side end by moving the building drum relative to the pressure-bond rollers of the stitcher apparatus starting from a vicinity of a center portion to the side in the axial direction,
• wherein the pressure-bond rollers of respective rows are advanced inward in the drum diameter direction, in a state that positions of the pressure-bond rollers are arranged in the drum peripheral direction such that at least portions of the pressure-bond rollers of contiguous rows overlap each other in the drum axial direction, while the pressure-bond rollers are not spaced apart by intervals in the drum peripheral direction as a whole,
• wherein each of the pressure-bond rollers are axially supported by a bracket provided at a front end portion of an output shaft of the air cylinder, and capable of being independently shifted, and
• retracting the pressure-bond rollers in a non-pressing operation state, so that an interval between the rollers in the peripheral direction of the drum is larger than a roller width.