Method and plant for manufacturing a belt structure, a belt package, and a crown structure for a vehicle tire

A plant for manufacturing a belt structure for a vehicle tire, comprising:

• an extrusion apparatus to form, in substantially continuous manner, a sheet of rubber-coated fabric;
• first conveying means to transport the sheet along a predetermined conveying direction;
• a first device for cutting the sheet along a first cutting direction forming a first predetermined angle with respect to the predetermined conveying direction to form multiple strips;
• a second device for preparing, from the multiple strips, a plurality of first and second half-strips by cutting each strip into two parts along a predetermined cutting direction;
• second conveying means for transporting the first and second half-strips along respective conveying directions;
• a third device for butt splicing the first half-strips to each other and the second half-strips to each other to form substantially continuous belt strips on the second conveying means;
• a fourth device for cutting the substantially continuous belt strips into portions;
• and
• at least one assembly drum adapted to support the belt-strip portions;
• wherein the sheet incorporates reinforcing cords substantially parallel to one another,
• wherein the multiple strips comprise a first predetermined length extending along the predetermined conveying direction,
• wherein the half-strips comprise a second predetermined length,
• wherein the half-strips are aligned along the respective conveying directions,
• wherein each half-strip incorporates reinforcing cords substantially parallel to one another, and
• wherein the belt-strip portions comprise respective predetermined lengths.

A method for manufacturing a belt package for a vehicle tire, comprising:

• preparing, in a substantially continuous manner, a plurality of strips along a predetermined conveying direction;
• preparing, in a substantially continuous manner, a plurality of half-strips by cutting each of the strips along a predetermined cutting direction;
• butt splicing, in a substantially continuous manner, respective half-strips to form belt strips;
• moving, in a substantially continuous manner, the belt strips toward at least one assembly drum;
• superposing, on the at least one assembly drum, portions of each of the belt strips to form a belt structure;
• transferring the belt structure to a separate assembly drum;
• and
• coaxially forming on the belt structure, supported by the separate assembly drum, a layer of rubber mixture comprising a plurality of circumferentially oriented reinforcing cords;
• wherein each strip comprises a first predetermined length extending along the predetermined conveying direction,
• wherein the half-strips comprise a second predetermined length,
• wherein the half-strips are aligned along respective conveying directions,
• wherein each half-strip incorporates reinforcing cords substantially parallel to one another,
• wherein the belt strips extend along the respective conveying directions,
• wherein the belt-strip portions comprise respective predetermined lengths,
• wherein the belt structure comprises radially superposed belt-strip portions,
• wherein reinforcing cords in each belt-strip portion are substantially parallel to one another,
• wherein, relative to an equatorial plane of the belt structure, the reinforcing cords in a first belt-strip portion are inclined in an opposite direction with respect to the reinforcing cords in a radially adjacent belt-strip portion, and
• wherein the layer of rubber mixture comprises a width substantially equal to a width of the belt structure.

A plant for manufacturing a belt package for a vehicle tire, comprising:

• a first extrusion apparatus to form, in a substantially continuous manner, a sheet of rubber-coated fabric;
• first conveying means to transport the sheet along a predetermined conveying direction;
• a first device for cutting the sheet along a first cutting direction forming a first predetermined angle with respect to the predetermined conveying direction to form multiple strips;
• a second device for preparing, from the multiple strips, a plurality of first and second half-strips by cutting each strip into two parts along a predetermined cutting direction;
• second conveying means for transporting the first and second half-strips along respective conveying directions;
• a third device for butt splicing the first half-strips to each other and the second half-strips to each other to form substantially continuous belt strips on the second conveying means;
• a fourth device for cutting the substantially continuous belt strips into portions;
• at least one assembly drum adapted to support the belt-strip portions;
• a second extrusion apparatus to form, in a substantially continuous manner, a ribbon or tape of rubber mixture incorporating a plurality of reinforcing cords substantially parallel to one another;
• means for cutting the ribbon or tape of rubber mixture into portions having predetermined length;
• a separate assembly drum;
• and
• a device for transferring a belt structure comprising at least two of the belt-strip portions toward the separate assembly drum;
• wherein the sheet of rubber-coated fabric incorporates reinforcing cords substantially parallel to one another,
• wherein the multiple strips comprise a first predetermined length extending along the predetermined conveying direction,
• wherein the half-strips comprise a second predetermined length,
• wherein the half-strips are aligned along the respective conveying directions,
• wherein each half-strip incorporates reinforcing cords substantially parallel to one another, and
• wherein the belt-strip portions comprise respective predetermined lengths.

A method for manufacturing a crown structure for a vehicle tire, comprising:

• preparing, in a substantially continuous manner, a plurality of strips along a predetermined conveying direction;
• preparing, in a substantially continuous manner, a plurality of half-strips by cutting each of the strips along a predetermined cutting direction;
• butt splicing, in a substantially continuous manner, respective half-strips to form belt strips;
• moving, in a substantially continuous manner, the belt strips toward at least one assembly drum;
• superposing, on the at least one assembly drum, portions of each of the belt strips to form a belt structure;
• transferring the belt structure to a separate assembly drum;
• coaxially forming on the belt structure, supported by the separate assembly drum, a layer of rubber mixture comprising a plurality of circumferentially oriented reinforcing cords;
• providing, in a substantially continuous manner, a tread by cutting a substantially continuous tread sheet of rubber mixture into portions having predetermined length;
• and
• coaxially applying the tread on the layer of rubber mixture;
• wherein each strip comprises a first predetermined length extending along the predetermined conveying direction,
• wherein the half-strips comprise a second predetermined length,
• wherein the half-strips are aligned along respective conveying directions,
• wherein each half-strip incorporates reinforcing cords substantially parallel to one another,
• wherein the belt strips extend along the respective conveying directions,
• wherein the belt-strip portions comprise respective predetermined lengths,
• wherein the belt structure comprises radially superposed belt-strip portions,
• wherein reinforcing cords in each belt-strip portion are substantially parallel to one another,
• wherein, relative to an equatorial plane of the belt structure, the reinforcing cords in a first belt-strip portion are inclined in an opposite direction with respect to the reinforcing cords in a radially adjacent belt-strip portion, and
• wherein the layer of rubber mixture comprises a width substantially equal to a width of the belt structure.

A plant for manufacturing a crown structure for a vehicle tire, comprising:

• a first extrusion apparatus to form, in a substantially continuous manner, a sheet of rubber-coated fabric;
• first conveying means to transport the sheet along a predetermined conveying direction;
• a first device for cutting the sheet along a first cutting direction forming a first predetermined angle with respect to the predetermined conveying direction to form multiple strips;
• a second device for preparing, from the multiple strips, a plurality of first and second half-strips by cutting each strip into two parts along a predetermined cutting direction;
• second conveying means for transporting the first and second half-strips along respective conveying directions;
• a third device for butt splicing the first half-strips to each other and the second half-strips to each other to form substantially continuous belt strips on the second conveying means;
• a fourth device for cutting the substantially continuous belt strips into portions;
• at least one assembly drum adapted to support the belt-strip portions;
• a second extrusion apparatus to form, in a substantially continuous manner, a ribbon or tape of rubber mixture incorporating a plurality of reinforcing cords substantially parallel to one another;
• first means for cutting the ribbon or tape of rubber mixture into portions having predetermined length;
• a separate assembly drum;
• a device for transferring a belt structure comprising at least two of the belt-strip portions toward the separate assembly drum;
• a third extrusion apparatus to form, in a substantially continuous manner, a continuous tread sheet of rubber mixture;
• third conveying means for transferring the continuous tread sheet of rubber mixture toward the separate assembly drum;
• and
• second means for cutting the continuous tread sheet of rubber mixture into portions having predetermined length to form a tread;
• wherein the sheet of rubber-coated fabric incorporates reinforcing cords substantially parallel to one another,
• wherein the multiple strips comprise a first predetermined length extending along the predetermined conveying direction,
• wherein the half-strips comprise a second predetermined length,
• wherein the half-strips are aligned along the respective conveying directions,
• wherein each half-strip incorporates reinforcing cords substantially parallel to one another, and
• wherein the belt-strip portions comprise respective predetermined lengths.