摘要:
Equipment for moulding and curing a green tyre includes a curing mould including a first bead moulding ring including a first surface for contacting a radially inner and axially inner surface portion of an annular fixing structure of the green tyre and a first sidewall plate including a second surface for contacting a radially inner and axially outer surface portion of the annular fixing structure. The first bead moulding ring is radially extendable from a contracted operating position to an expanded operating position so as to delimit a portion of the annular fixing structure between the first sidewall plate and the first bead moulding ring, and the first bead moulding ring is translatable towards the first sidewall plate for generating a first squeezing pressure on the annular fixing structure. The equipment further includes an inflatable bladder associated for operation with the curing mould.
摘要:
A green tire is built on a forming drum and then transferred to a bead molding and pre-vulcanization station where each bead of the tire is molded by tightening it between two axially opposite clamping surfaces respectively carried by an axially external annular locating element and an axially internal annular locating element consisting of radially expandable circumferential sectors. The tightened beads can be pre-vulcanized through heat supply by means of electric resistors integrated into the axially external annular locating elements. The tire with the tightened and possibly pre-vulcanized beads is transferred to a molding cavity having an inner wall substantially conforming to the shape of an outer surface of the molded tire to carry out molding and complete vulcanization of the tire.
摘要:
A green tyre is built on a rigid toroidal support externally having a forming surface of a conformation corresponding to the inner conformation of the tyre. The built tyre is removed from the rigid toroidal support and engaged on an expandable toroidal support comprising a bladder. The green tyre engaged on the expandable toroidal support is introduced into a vulcanization mould and submitted to a vulcanization cycle.
摘要:
Apparatus and method for molding a tire (110) with an expandable bead molding ring assembly (250) having a two-stage movement from a retracted and disengaged state, to a radially expanded state, to an expanded and engaged state for molding a tire bead (112b). The two-stage movement is accomplished using a simple assembly of easily manufactured parts, and is driven by a simple continuous downward (axially outward) movement (320) of a hub (209) of a mold press (220). A combination of annular elements with springs converts the hub movement to the desired two-stage movement of segments (254, 256) of a segmented bead molding ring (252). Frustraconical cam surfaces (258, 266) are used to divide axially directed forces (420a, 420b) from the mold press movement (320) into radial force components (410a, 410b) and axial force components (415a, 415b) for causing corresponding radial movements (310) and axial movements (315) during the two stage movement. Spring resistances are balanced, and stopping surfaces are provided in order to control and properly sequence the two-stage movement. The elements of the expandable bead molding ring assembly are preferably assembled with a sidewall mold to form a single unit (280) that is easily maintained and easily switched in and out of the mold press for mold changeover to adapt to different profiles to be molded on beads of different tire constructions.
摘要:
A tyre includes a toroidal ring-shaped carcass structure with at least one carcass ply associated with at least one annular fixing structure, as well as a tread band positioned radially externally with respect to the carcass structure. The annular fixing structure includes a radially inner and axially inner surface and a radially inner and axially outer surface, the surfaces being substantially opposed to each other. The radially inner and axially inner surface and radially inner and axially outer surface are shaped by successive application of a first squeezing pressure produced by a first surface and a second surface of a curing mould that are brought towards each other, as well as a second squeezing pressure produced by bringing the first and second surfaces closer together. The radially inner and axially inner surface and/or radially inner axially outer surface have a shape that includes air evacuation channels.
摘要:
A green tyre is built on a rigid toroidal support externally having a forming surface of a conformation corresponding to an inner conformation of the tyre. The built tyre is removed from the rigid toroidal support and engaged on an expandable toroidal support which includes a bladder. The green tyre engaged on the expandable toroidal support is introduced into a vulcanisation mould and submitted to a vulcanisation cycle.
摘要:
Apparatus and method for molding a tire (110) with a radially expandable bead molding ring (252). When expanded, the bead molding ring has a circumferentially continuous radially outward-facing surface (259) for molding the bead. The bead molding ring comprises a plurality of segments (254, 256), half of the segments being first segments (254) that are complementary to, and circumferentially alternated with second segments (256). The first segments are wedge shaped, having circumferentially lateral faces (255) that converge towards the radially outward-facing bead molding surface of the bead molding ring, the first segment lateral faces being planar and oriented in the axial direction; and the second segments have lateral faces (257) that are complementary to the first segment lateral faces, such that radially outward movement of the first segments (254) causes radially outward movement of the second segments (256). Guide rods (260) restrict first and second segments to radial movement (310) only. The elements of the bead molding ring are preferably combined in a single assembly (280) with the sidewall mold to form a unit that is easily maintained and changed to adapt to different profiles to be molded on beads of different tire constructions. Expansion of the bead molding ring can be driven by a simple wedging action caused by a single frustraconical cam 266.
摘要:
Apparatus and method for molding a tire (110) with a radially expandable bead molding ring (252). When expanded, the bead molding ring has a circumferentially continuous radially outward-facing surface (259) for molding the bead. The bead molding ring comprises a plurality of segments (254, 256), half of the segments being first segments (254) that are complementary to, and circumferentially alternated with second segments (256). The first segments are wedge shaped, having circumferentially lateral faces (255) that converge towards the radially outward-facing bead molding surface of the bead molding ring, the first segment lateral faces being planar and oriented in the axial direction; and the second segments have lateral faces (257) that are complementary to the first segment lateral faces, such that radially outward movement of the first segments (254) causes radially outward movement of the second segments (256). Guide rods (260) restrict first and second segments to radial movement (310) only. The elements of the bead molding ring are preferably combined in a single assembly (280) with the sidewall mold to form a unit that is easily maintained and changed to adapt to different profiles to be molded on beads of different tire constructions. Expansion of the bead molding ring can be driven by a simple wedging action caused by a single frustraconical cam 266.