In a method for producing an unvulcanized ring-shaped rubber member a front edge portion of a band-like rubber member conveyed by a conveyor is disposed on an outer circumferential surface of a forming drum, and the forming drum is rotated to wind a length of the band-like rubber member on the outer circumferential surface and a rear edge portion is held by rear edge holding portions arranged side by side in a width direction. Using distribution data on a length of the band-like rubber member in the width direction, an amount of movement of movement portions in a front-rear direction is controlled to adjust the degree of elongation around the held portion of the rear edge portion in the front-rear direction that is held by each of the rear edge holding portions, and the front and rear edge portions are bonded to produce a ring-shaped rubber member.

An apparatus for building tyres for vehicle wheels are described. A substantially cylindrical carcass sleeve, having at least one carcass ply, includes consecutively adjacent strip-like elements laid one after the other around the circumferential extension of a substantially cylindrical deposition surface. Circumferentially consecutive strip-like elements laid one after the other form overlap zones along respective longitudinal edges superimposed on each other. Each overlap zone has, along a longitudinal extension thereof, terminal sections that are laterally opposite with respect to an intermediate section. The intermediate section of each overlap zone has greater width than the width of the terminal sections.

A belt cover layer is formed by spirally winding belt cover materials including a first cover material and a second cover material. When one side in a tire width direction with respect to a tire equatorial plane is defined as a first side and another side is defined as a second side, the first cover material is disposed from a position between a shoulder region on the second side and the tire equatorial plane to a shoulder region on the first side. The second cover material is disposed from a position between the shoulder region (Ash) on the first side and the tire equatorial plane to the shoulder region on the second side. The first cover material and the second cover material have an overlapping portion at a position where positions in the tire width direction become positions identical to one another.

A tyre for vehicle wheels includes a carcass structure with at least one carcass ply formed by strip-like elements consecutively adjacent one after the other along a circumferential extension and having overlap zones along respective longitudinal edges superimposed on each other. Each overlap zone has, along a longitudinal extension thereof, terminal sections that are laterally opposite with respect to an intermediate section. The intermediate section of each overlap zone has an intermediate overlap width greater than a terminal overlap width of the terminal sections.

In a method for producing an unvulcanized ring-shaped rubber member a front edge portion of a band-like rubber member conveyed by a conveyor is disposed on an outer circumferential surface of a forming drum, and the forming drum is rotated to wind a length of the band-like rubber member on the outer circumferential surface and a rear edge portion is held by rear edge holding portions arranged side by side in a width direction. Using distribution data on a length of the band-like rubber member in the width direction, an amount of movement of movement portions in a front-rear direction is controlled to adjust the degree of elongation around the held portion of the rear edge portion in the front-rear direction that is held by each of the rear edge holding portions, and the front and rear edge portions are bonded to produce a ring-shaped rubber member.

A manufacturing method includes the steps of: (A) preparing first and second sheet pieces 20a and 20b made of unvulcanized rubber; and (B) winding a long sheet 26 on a drum 6. The long sheet 26 includes the first and second sheet pieces 20a and 20b, and the second sheet piece 20b has a front edge joined to a rear edge of the first sheet piece 20a. Preferably, the step (B) includes the steps of: (B′1) joining the front edge of the second sheet piece 20b to the rear edge of the first sheet piece 20a to obtain the long sheet 26; and (B′2) feeding the sheet 26 from a servicer 4 to the drum 6 while rotating the drum 6 to wind the sheet 26 on the drum 6.

A manufacturing device for an unvulcanized band-shaped rubber member is provided. A position sensor detects, across a width direction of the band-shaped rubber member, leading and trailing ends of the band-shaped rubber member placed in a flat state on a conveyor, holding portions arranged side by side in the width direction hold at least one of the leading or trailing ends, with movement portions allowing the holding portions to move individually in a front-rear direction, the leading and the trailing ends are held by the leading and trailing end holding mechanisms, respectively, and a control unit controls a displacement of the movement portions in the front-rear direction based on data from the position sensor and a target length to adjust elongation in the front-rear direction at or near a held portion held by each of the holding portions to achieve the target length of the band-shaped rubber member.

An apparatus for building tyres for vehicle wheels are described. A substantially cylindrical carcass sleeve, having at least one carcass ply, includes consecutively adjacent strip-like elements laid one after the other around the circumferential extension of a substantially cylindrical deposition surface. Circumferentially consecutive strip-like elements laid one after the other form overlap zones along respective longitudinal edges superimposed on each other. Each overlap zone has, along a longitudinal extension thereof, terminal sections that are laterally opposite with respect to an intermediate section. The intermediate section of each overlap zone has greater width than the width of the terminal sections.

A process and an apparatus for building tyres and a tyre for vehicle wheels are described. A substantially cylindrical carcass sleeve, having at least one carcass ply, is formed by laying consecutively adjacent strip-like elements one after the other around the circumferential extension of a substantially cylindrical deposition surface. Circumferentially consecutive strip-like elements are laid one after the other to form overlap zones along respective longitudinal edges superimposed on each other. Each overlap zone has, along a longitudinal extension thereof, terminal sections that are laterally opposite with respect to an intermediate section. The intermediate section of each overlap zone has greater width than the width of the terminal sections.

In a method for manufacturing a pneumatic tire, molding of a green tire has an assembly step of bonding an inner liner and an unvulcanized rubber sheet with end portions thereof in a width direction being displaced from each other by 50 mm to 500 mm in the width direction to manufacture a laminate, cutting the laminate to have a constant length corresponding to a width of a drum to manufacture a cut sheet, and a joining step of winding the cut sheet on entire circumference of the drum such that a cut surface thereof extends in a circumferential direction of the drum and the inner liner is disposed on an inner surface side, and joining the end portions of the inner liner and joining the end portions of the unvulcanized rubber sheet such that positions of the joined end portions are displaced by a constant distance.