CN-122029036-A - Method and apparatus for manufacturing layered annular components in the manufacture of tires

Abstract

In the manufacture of tyres for vehicles, one or more layered annular components are obtained by arranging around a central geometric axis (X) a radially external annular layer (7 a) having a toroidal shape, said radially external annular layer having a concave surface directed towards the central geometric axis (X). A radially inner annular layer (7 b) having a toroidal shape is then applied against the radially outer annular layer (7 a), said radially inner annular layer having a convex surface directed away from the central geometric axis (X). The axially opposite end flaps (26) of the radially outer annular layer (7 a) are moved apart from each other before the radially inner annular layer (7 b) is applied.

Inventors

• C. Decorr
• C. Pupi
• S.SANGIOVANNI

Assignees

• 倍耐力轮胎股份公司

Dates

Publication Date

20260512

Application Date

20241018

Priority Date

20231102

Claims (20)

1. 1. A method for manufacturing a layered annular component in the manufacture of a tyre for vehicles, comprising: -arranging around a central geometric axis (X) a radially outer annular layer (7 a) having a toroidal shape with a concave face directed towards said central geometric axis (X); The axially opposite end flaps (26) of the radially outer layer (7 a) are moved apart from each other before the subsequent annular layer is applied internally to the radially outer annular layer (7 a).
2. 2. Method according to claim 1, wherein the subsequent annular layer is a radially inner annular layer (7 b) having a toroidal shape with a convex surface directed away from the central geometrical axis (X).
3. 3. Method according to claim 2, wherein the initial contact between the radially inner annular layer (7 b) and the radially outer annular layer (7 a) occurs near an axial mid-line plane (M) equidistant from the axially opposite end flaps (36) of the radially outer layer (7 a).
4. 4. A method according to claim 2 or 3, wherein the axially opposite end flaps (36) of the radially outer layer (7 a) are moved apart from each other until a mutual second axial distance (L2) of not less than a reference distance (Lx) is reached, which reference distance is detectable between the axially opposite end flaps (37) of the radially inner annular layer (7 b).
5. 5. The method according to claim 4, wherein: The second axial distance (L2) is detectable along a first axial direction (d 1) passing through an axial mid-line plane (M) equidistant from the axially opposite end flaps (36) of the radially outer annular layer (7 a); -said reference distance (Lx) is detectable along a second axial direction (d 2) passing through said axial mid-line plane (M); Wherein a first radial distance (Dr 1) detectable between a radially inner surface of the radially outer annular layer (7 a) and an intersection of the axial mid-line plane (M) and the first axial direction (d 1) is equal to a second radial distance (Dr 2) detectable between a radially outer surface of the radially outer annular layer (7 a) and an intersection of the axial mid-line plane (M) and the second axial direction (d 2).
6. 6. The method according to one or more of claims 2 to 5, further comprising the act of re-approaching the axially opposite end flaps (36) of the radially outer annular layer (7 a) at the end of the application of the radially inner annular layer (7 b).
7. 7. Method according to claim 6, wherein the re-approaching of the axially opposite end flap (36) of the radially outer annular layer (7 a) is performed while the radially inner annular layer (7 b) is positioned against the radially outer annular layer (7 a) at least at an axial mid-line plane (M) substantially equidistant from the end flap itself.
8. 8. Method according to claim 6 or 7, wherein after re-approaching the axially opposite end flaps (36) of the radially outer annular layer (7 a) are in contact with the radially inner annular layer (7 b).
9. 9. The method according to one or more of the preceding claims, wherein arranging said radially outer annular layer (7 a) comprises: -laying said radially outer annular layer (7 a) according to a substantially cylindrical shape around said central geometric axis (X); Expanding a profiling drum (17) within said radially outer annular layer (7 a) so as to toroidally shape said radially outer annular layer (7 a), said profiling drum having a radially outer and axially convex expanding surface (19).
10. 10. The method according to one or more of claims 2 to 9, wherein applying the radially inner annular layer (7 b) comprises: -laying the radially inner annular layer (7 b) according to a substantially cylindrical shape around the central geometric axis (X); expanding a profiling drum (17) within said radially inner annular layer (7 b) so as to toroidally shape said radially inner annular layer (7 b), said profiling drum having a radially outer and axially convex expanding surface (19).
11. 11. A method as claimed in claim 10, wherein the initial contact between the radially inner annular layer (7 b) and the radially outer annular layer (7 a) occurs simultaneously with the copying drum (17) reaching a maximum expansion condition.
12. 12. The method according to one or more of claims 2 to 11, further comprising the act of retaining said radially outer annular layer (7 a) at a radially outer surface thereof during the application of said radially inner annular layer (7 b).
13. 13. An apparatus for manufacturing a layered annular component in the building of a tyre for vehicles, comprising: An annular retaining member (23) having a toroidal shape with a concave face directed towards a central geometric axis (X); -an application device comprising a copying drum (17) having a toroidal shape with a convexity directed away from the central geometric axis (X); wherein the annular retaining member (23) comprises two axially opposite retaining annular portions (27 a), each directed towards the central geometric axis (X); wherein the retaining ring portions (27 a) are movable relative to each other.
14. 14. Apparatus according to claim 13, wherein said retaining ring portion (27 a) is axially movable under command of one or more axial movement actuators (30).
15. 15. Apparatus as claimed in claim 13 or 14, wherein each of said retaining annular portions (27 a) has a suction duct (33) leading to a respective opening distributed and directed towards said central geometric axis (X).
16. 16. The apparatus according to one or more of claims 13 to 15, wherein said annular retaining member (23) comprises a plurality of grip elements (26) distributed circumferentially around said central geometric axis (X).
17. 17. The device according to claim 16, wherein the gripping element (26) is radially movable with respect to the central geometric axis (X).
18. 18. Apparatus as claimed in claim 16 or 17, wherein each of said gripping elements (26) comprises two holding blocks (27) axially side by side with respect to each other, each belonging to one of said holding annular portions (27 a).
19. 19. The apparatus as claimed in claim 18, wherein each of the gripping elements (26) comprises a support element (28) carrying the retention block (27) axially slidable with respect to the respective support element (28).
20. 20. Apparatus according to claim 18 or 19, wherein the holding blocks (27) belonging to each gripping element (26) are interconnected to each other by a threaded rod (29) which can be actuated in rotation by the axial movement actuator (30).

Description

Method and apparatus for manufacturing layered annular components in the manufacture of tires Technical Field The present invention relates to a method for manufacturing a layered annular component in the manufacture of a tyre. The invention also relates to an apparatus for manufacturing a layered annular component in the building of a tyre for vehicles. In the examples described herein, the present invention is employed to manufacture belt structures for motor vehicle tires. However, the invention can also be advantageously used for manufacturing annular tyre components other than belt structures, and not only on tyres for motor vehicles, but also on tyres for cars, trucks and the like. Background A tyre for vehicle wheels generally comprises a carcass structure comprising at least one carcass ply having respective opposite end flaps engaged with respective annular anchoring structures integrated in regions generally identified by the name "beads" having an inner diameter substantially corresponding to the so-called "fitting diameter" of the tyre on a respective mounting rim. The carcass structure is associated with a belt structure, which may comprise one or more belt layers radially superposed with respect to each other and to the carcass ply, having textile, metallic or hybrid reinforcing cords with a crossed orientation and/or an orientation substantially parallel to the circumferential development direction of the tyre (at 0 degrees). A tread band is applied in a radially external position with respect to the belt structure, said tread band also being made of elastomeric material, such as other constituent semifinished products of the tyre. Respective sidewalls made of elastomeric material may also be applied on the lateral surfaces of the carcass structure in axially external positions, each extending from one of the lateral edges of the tread band up to the respective annular anchoring structure to the beads. In "tubeless" tires, an impermeable cover, commonly referred to as a "liner", covers the inner surface of the tire. The terms "radial" and "axial" and the expressions "radially inner/outer" and "axially inner/outer" are used with reference to the radial direction and the axial direction of the tire, respectively, i.e. the direction perpendicular to the rotation axis of the tire and the direction parallel to the rotation axis of the tire. The radial plane of the tyre contains its rotation axis. The terms "circumferential" and "circumferentially" are used instead with reference to the annular stretch of the tyre, with which the stretch that the tyre presents in the rolling direction in the operating condition is clarified. The "rotation axis" of the green tyre refers to the axis corresponding to the rotation axis of the molded and cured tyre when mounted on the respective mounting rim in the operating condition. The term "component" of a tire refers to any part of the tire that is capable of performing its own function, or is part of that part. The term "layered annular component" of a tire refers to a component of a tire comprising a plurality of layers radially opposite with respect to the axis of rotation of the tire, wherein the plurality of layers comprises at least one radially outer annular layer and at least one radially inner annular layer, and wherein each layer comprises at least one matrix of elastomeric material. Preferably, the layered annular component of the tire may be a collection comprising two or more belt layers, and in particular may be a belt structure, or more broadly, a collection comprising two or more layers intended to form part of a green tire, each layer being selected from, for example, a liner, a substrate, one or more carcass plies, one or more belt layers, an under-belt layer, an under-tread layer, sidewalls, sidewall inserts, a tread band, and the like. The term "elastomeric material" is intended to mean a composition comprising at least one elastomeric polymer and at least one reinforcing filler. Preferably, such compositions further comprise additives such as, for example, cross-linking agents and/or plasticizers. Due to the presence of the cross-linking agent, by heating such a material, it can be cross-linked to form the final manufactured product. The term "semifinished product" refers to a prefabricated finished product, i.e. a finished product that is manufactured before the production of the tyre and generally outside the building equipment. The finished product is preferably prefabricated in full width, i.e. with a predetermined dimensional width of the layers of the part for which the semifinished product is suitable to be formed. The semifinished product may be made of elastomeric material only, i.e. comprising only one elastomeric matrix, or the semifinished product may be reinforced with at least one reinforcing cord made of textile material and/or metallic material and/or hybrid material. "Tire for two-wheeled vehicles" (in particular motorcycles)