Apparatus for building a carcass structure of a tyre for vehicle wheels

An apparatus for building a carcass structure of a tyre for a vehicle wheel on a forming support, the carcass structure comprising a carcass ply, and, at an edge of the carcass ply, an annular anchoring structure comprising a substantially circumferential annular insert and a filling insert associated with the substantially circumferential annular insert, comprising:

• a positioning member of the annular anchoring structure on the end edge of the carcass ply, wherein the positioning member is configured to exert a pushing action on a side surface of the annular anchoring structure in order to bring the annular anchoring structure in contact with the end edge of the carcass ply and to press the annular anchoring structure against a shoulder of the forming support opposite to the side surface of the annular anchoring structure;
• a ring having a side surface with a predetermined profile, wherein the predetermined profile of the side surface of the ring is conjugated to a profile of a side surface of the filling insert when pulled down on the end edge of the carcass ply to act on the entire side surface of the filling insert annularly and radially;
• and
• a turning-up member of a turned up end portion of the carcass ply;
• wherein the ring is configured to slide with respect to the positioning member and to act on the filling insert while the positioning member retains the substantially circumferential annular insert in a contact position with the end edge of the carcass ply by continuing to exert the pushing action and before the turning-up member forms the turned up end portion of the carcass ply,
• wherein the side surface of the ring moves only along a direction parallel to an axis of rotation of the forming support.