Mould and process for vulcanising tyres for vehicles wheels

A mould for vulcanising tyres for vehicle wheels, comprising:

• at least one sidewall plate on which a moulding surface is defined and contacts an axially external surface of a sidewall of a green tyre,
• a removable insert arranged to be received in a seat which is made in the sidewall plate and open on the moulding surface, wherein the removable insert comprises a main body on which a base surface is defined and contacts a portion of the axially external surface of the sidewall of the green tyre, and
• a retaining member for retaining the removable insert inside the seat,
• wherein the retaining member comprises at least one locking element which is mounted on one out of the removable insert and the sidewall plate and comprises a first contact surface for contacting the other out of the removable insert and the sidewall plate, and wherein the at least one locking element can be moved in an operating direction, which is incident with respect to an insertion direction of the removable insert into the seat, between a locking position, in which the removable insert is retained inside the seat, and a release position, in which the removable insert is free to leave the seat;
• wherein the removable insert comprises a rod which extends in the insertion direction, on the opposite side to the base surface, and the first contact surface engages the removable insert at the rod to retain the removable insert in the seat
• and wherein a first shoulder is defined on the rod, wherein the first shoulder:
• diverges away from the main body;
• inclines with respect to a longitudinal axis of the rod at an angle between 10° and 70°;
• and
• is configured to contact the first contact surface with a force, wherein at least part of the force urges the rod by the first contact surface in a direction parallel to an insertion direction X, towards a free end of the rod, actively forcing the removable insert toward the seat, when the locking element is in the locking position;
• wherein, when the locking element is in the locking position, the locking element is not in contact with a bottom of a circumferential groove that is defined at least partly by the first shoulder.