A tire building drum is rotatably mounted on a central drive shaft and includes a center portion. A center mechanism for the drum is disposed in the center portion and includes a hub that seats on and is secured to the central drive shaft. An axially-extending piston seats on and extends circumferentially about the hub. A cylinder cooperates with the hub and the piston to form a pneumatic chamber. A plurality of links are connected to the piston and a plurality of segment bars are disposed about the circumference of the center mechanism. Each one of the segment bars is connected to selected links and seats between a lip of the cylinder and a distal end plate. When compressed air is introduced into the pneumatic chamber, the piston moves in an axial direction, actuating movement of the links and in turn actuating radial movement of the segment bars.

In a process for building tyres for vehicle wheels, a carcass sleeve is arranged on a shaping drum including two half-drums and two supports. Each support is operatively associated with one of the half-drums and carries a plurality of turning-up levers having free ends positioned close to the respective half-drum. Two annular anchoring structures are disposed around the carcass sleeve and each of the two supports is locked to the respective half-drum by interposing only stiff mechanical elements in mutual contact between the support and the half-drum. The carcass sleeve is shaped in a toroidal conformation, by setting a threaded shaft in rotation and moving the half-drums close to each other. Subsequently, each of the two supports is unlocked from the respective half-drum and the threaded shaft is set in rotation to move each support close to the respective half-drum and lift up the free ends of the turning-up levers until the end flaps of the carcass sleeve are turned up around the annular anchoring structures.

A process and a drum for looping annular anchoring structures in a process for building tyres for vehicle wheels includes: depositing a loop on a drum including a radially expandable/contractible intermediate annular portion and, in a position axially adjacent to the opposite axial ends of said intermediate annular portion, a pair of radially expandable/contractible lateral annular portions; associating an annular anchoring structure with a radially outer annular surface portion of the loop defined at the intermediate annular portion; and turning up each of opposite end edges of the loop on the annular anchoring structure through the lateral annular portions as a result of a thrusting stress imparted by a respective lateral annular portion of said pair of lateral annular portions because of a synchronous radial movement and a synchronous axial displacement of a respective plurality of circumferentially adjacent first angular sectors.

A method in accordance with the present invention manufactures a tire with a biaxial monolayer belt component (MBC). The method comprises the steps of: winding a cord continuously about a first drum according to a pre-defined pattern to create a mesh of cords defining a single belt/overlay structure; adjusting the structure to a predetermined position on the first drum by laser lights; applying a tread component to the structure; transferring the structure and tread component to a second drum; applying the structure and tread component to a carcass component on the second drum; reducing pressure of the carcass component by a predetermined amount; and stitching the structure and tread component to the carcass component.

A process and an apparatus for building tyres, wherein, in the process, a carcass sleeve including at least one carcass ply and a pair of annular anchoring structures is transferred to a shaping drum including flange elements that are each engageable with one of said annular anchoring structures. The carcass sleeve is shaped according to a toroidal configuration by means of mutual axial approaching of the flange elements. Before shaping, annular grip elements respectively carried by the flange elements are radially expanded, each inside one of the annular anchoring structures, in order to engage the carcass sleeve. The annular anchoring structures are moved axially apart from each other before engaging the carcass sleeve by means of the annular grip elements.

A tire comprises a sealing layer comprising a junction (21) extending in a main direction (D4) forming, with the circumferential direction (Z) of the tire: in a portion (15S) of the sealing layer extending axially in radial line with the working layer, an angle (ES) ranging, in absolute value, from 20 to 60, and in a portion (15F) of the sealing layer extending radially in each sidewall, an angle (EF), in absolute value, strictly greater than the angle (ES) of the main direction (D4) of the junction (21) in the portion (15S) of the sealing layer extending axially in radial line with the working layer.