In an inner mold method, a pull-out force of extracting inner mold segments from a vulcanized tire is reduced. A rigid inner mold 1 is provided with an annular inner mold body 2 having a tire molding surface S. A rigid core 1 is put into a vulcanization mold B for each green tire T formed on the tire molding surface s, whereby the green tire T is vulcanization-molded between the vulcanization mold B and the inner mold body 2. The inner mold body 2 comprises a plurality of inner mold segments 5 divided in the circumferential direction. A coating layer 11 having rubber release property is formed on the tire molding surface S.

Provided is a rigid core for tire formation that limits the rubber stuck between inner mold segments in an inner mold segment while minimizing the occurrence of unevenness in the radial direction between inner mold segments that is caused by thermal expansion. A core main body 2 is divided into: a first inner mold segment 5A in which both circumferential end surfaces 5As are inclined radially inward in a direction in which the circumferential width increases; a second inner mold segment 5B that is arranged in an alternating manner with the inner mold segment 5A and in which both circumferential end surfaces 5Bs are inclined radially inward in a direction in which the circumferential width decreases; and a butting member 6 that is arranged between the first inner mold segment 5A and the second inner mold segment 5B. Young's modulus Ea of the butting member 6 is smaller than Young's modulus Eb of the first and second inner mold segments 5A and 5B.

Provided is a rigid core for tire formation that limits the rubber stuck between inner mold segments in an inner mold segment while minimizing the occurrence of unevenness in the radial direction between inner mold segments that is caused by thermal expansion. A core main body 2 is divided into: a first inner mold segment 5A in which both circumferential end surfaces 5As are inclined radially inward in a direction in which the circumferential width increases; a second inner mold segment 5B that is arranged in an alternating manner with the inner mold segment 5A and in which both circumferential end surfaces 5Bs are inclined radially inward in a direction in which the circumferential width decreases; and a butting member 6 that is arranged between the first inner mold segment 5A and the second inner mold segment 5B. Young's modulus Ea of the butting member 6 is smaller than Young's modulus Eb of the first and second inner mold segments 5A and 5B.

A toroidal forming drum and a process for budding tyres. The toroidal forming drum is expanded within a shaped carcass sleeve for supporting the carcass sleeve against an abutment surface externally provided by the forming drum. An elementary semi--finished product is applied around the shaped carcass sleeve by pressing the elementary semi-finished product toward the abutment surface. The abutment surface has circumferential rows of solid portions alternated with hollow portions. The solid portions, arranged along axially opposite circumferential edges of the abutment surface, have a transverse size between 10% and 60% of a transverse size presented by the solid portions arranged in proximity to an axial centreline plane of the abutment surface.

A toroidal forming drum and a process for budding tyres. The toroidal forming drum is expanded within a shaped carcass sleeve for supporting the carcass sleeve against an abutment surface externally provided by the forming drum. An elementary semi--finished product is applied around the shaped carcass sleeve by pressing the elementary semi-finished product toward the abutment surface. The abutment surface has circumferential rows of solid portions alternated with hollow portions. The solid portions, arranged along axially opposite circumferential edges of the abutment surface, have a transverse size between 10% and 60% of a transverse size presented by the solid portions arranged in proximity to an axial centreline plane of the abutment surface.

The facility comprises a tire-building station that is configured to form an uncured tire on a core. A curing station is configured to cure the assembly formed by the core and the uncured tire so as to obtain a cured annular tire. An extraction station is configured to separate, after the curing operation, the cured tire from the core. The curing station has a first, heating, thermal source which presses against the exchange face of the core for the curing operation and is then dissociated from the core and remains in the curing station in order to leave the exchange face free again when the core and the cured tire are transferred to the extraction station so that a second, refrigerating, thermal source of the extraction station takes the place of the first thermal source in contact with the exchange face of the core so as to cool the core.

The facility comprises a tire-building station that is configured to form an uncured tire on a core. A curing station is configured to cure the assembly formed by the core and the uncured tire so as to obtain a cured annular tire. An extraction station is configured to separate, after the curing operation, the cured tire from the core. The curing station has a first, heating, thermal source which presses against the exchange face of the core for the curing operation and is then dissociated from the core and remains in the curing station in order to leave the exchange face free again when the core and the cured tire are transferred to the extraction station so that a second, refrigerating, thermal source of the extraction station takes the place of the first thermal source in contact with the exchange face of the core so as to cool the core.