Process and apparatus for manufacturing tyres for vehicle wheels

An apparatus for manufacturing tyres for vehicle wheels, each tyre comprising a carcass structure including at least one carcass ply, a tread band at a radially external position to said carcass structure and a belt structure interposed between said carcass structure and tread band, the tyres being manufactured including tyres comprising carcass plies made by laying down an even whole number of strip-like elements and tyres comprising carcass plies made by laying down an odd whole number of strip-like elements, comprising:

• a forming drum having at least one radially external laying surface;
• devices for building at least one carcass ply around said radially external surface, said at least one carcass ply having axially opposite end flaps;
• wherein the devices for building at least one carcass ply around said radially external surface comprise:
• devices for setting the forming drum in rotation around a geometric rotation axis thereof;
• a first laying unit and a second laying unit mounted at mutually opposite portions of the forming drum and adapted to apply a plurality of strip-like elements along the circumferential extension of the forming drum;
• an adjustment device for shifting the first laying unit along an arced adjustment path which lies in a plane orthogonal to the geometric rotation axis, the arced adjustment path being an arc of a circumference coaxial with the geometric rotation axis for applying a single strip-like element;
• a bearing structure adapted to carry the forming drum;
• a first frame installed on the bearing structure above the forming drum and carrying the first laying unit;
• and
• a second frame installed on the bearing structure under the forming drum and carrying the second laying unit, wherein the adjustment device is mounted between the bearing structure and the first frame to shift the first laying unit along said adjustment path and wherein the adjustment device comprises a supporting plate hinged on the bearing structure around a hinge axis coincident with the geometric rotation axis and at least one actuator disposed between the supporting plate and the bearing structure, the first frame being installed on said supporting plate.