Process and apparatus for manufacturing tyres

Patent metadata

Field	Value
Publication number	US-9630369-B2
Application number	US-44939807-A
Country	US
Kind code	B2
Filing date	Feb 15, 2007
Priority date	Feb 15, 2007
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

A carcass ply is applied around an outer surface of a building drum, according to an application diameter greater than the fitting diameter of the tire. An annular anchoring structure defining the fitting diameter is coaxially engaged around each of the end flaps. An outer sleeve including at least one belt structure possibly associated with a tread band is disposed at a coaxially centered position around the carcass sleeve applied onto the building drum. Through axial approaching of two halves forming the building drum, the carcass sleeve is shaped into a toroidal configuration to determine application of same against a radially internal surface of the outer sleeve.

First claim

The invention claimed is:

1. A process for manufacturing tyres, the process comprising the steps of:
applying at least one carcass ply according to an application diameter around at least one outer surface of a building drum, said at least one carcass ply having axially opposite end flaps;
coaxially engaging around each of the end flaps, an annular anchoring structure defining a fitting diameter smaller than said application diameter so as to make a carcass sleeve;
positioning an outer sleeve comprising at least one belt structure at a coaxially centered position around said carcass sleeve applied onto said building drum;
shaping said carcass sleeve from the application diameter into a toroidal configuration to apply said carcass sleeve against a radially internal surface of said outer sleeve; and
after coaxially engaging said annular anchoring structures and before shaping said carcass sleeve, axially approaching locking members towards said annular anchoring structures, removably fastening said locking members to the building drum, and then moving a circumferentially continuous annular thrust ring carried by each of said locking members in an axial direction into direct contact with an elastically deformable annular element carried by each of said locking members to deform the annular element from a rest condition to a radially expanded condition against each of the annular anchoring structures,
wherein the locking members do not engage the annular anchoring structures when coaxially engaging the annular anchoring structures around the end flaps,
wherein the annular anchoring structures are locked relative to the building drum during the shaping step by said locking members,
wherein said locking members are disengaged from the building drum after shaping said carcass sleeve, and
wherein the at least one outer surface of the building drum has a same diameter when the at least one carcass ply is applied, when the annular anchoring structures are coaxially engaged around the end flaps, and when the locking members are engaged to the building drum.

2. The process as claimed in claim 1 , wherein application of said at least one carcass ply comprises a step of applying a plurality of strip-like elements disposed in succession along a circumferential extension of the outer surface of the building drum.

3. A process as claimed in claim 1 , wherein application of said at least one carcass ply comprises a step of circumferentially winding a manufactured article in the form of a continuous strip around the outer surface of the building drum.

4. The process as claimed in claim 1 , wherein said application diameter is greater than or equal to about 102% of the fitting diameter.

5. The process as claimed in claim 4 , wherein application of said at least one carcass ply comprises a step of applying a plurality of strip-like elements disposed in succession along a circumferential extension of the outer surface of the building drum, and wherein said strip-like elements applied onto said building drum have at least one longitudinal axis parallel to an axis of the building drum.

6. The process as claimed in claim 4 , wherein application of said at least one carcass ply comprises a step of applying a plurality of strip-like elements disposed in succession along a circumferential extension of the outer surface of the building drum, and wherein said strip-like elements applied onto said building drum form an angle different from zero between a longitudinal axis thereof and an axis of the building drum.

7. A process as claimed in claim 1 , wherein said application diameter is smaller than or equal to about 120% of the fitting diameter.

8. A process as claimed in claim 1 , wherein said application diameter is greater than or equal to about 105% of the fitting diameter.

9. The process as claimed in claim 1 , wherein said application diameter is smaller than or equal to about 115% of the fitting diameter.

10. The process as claimed in claim 1 , wherein the application diameter is greater than or equal to about 30% of an inner diameter of the outer sleeve.

11. The process as claimed in claim 1 , wherein the application diameter is smaller than or equal to about 90% of an inner diameter of the outer sleeve.

12. The process as claimed in claim 1 , wherein the application diameter is greater than or equal to about 50% of an inner diameter of the outer sleeve.

13. The process as claimed in claim 1 , wherein the application diameter is smaller than or equal to about 80% of an inner diameter of the outer sleeve.

14. The process as claimed in claim 1 , wherein a difference between the application diameter and the fitting diameter is greater than or equal to about 2% of a difference between an inner diameter of the outer sleeve and the fitting diameter.

15. The process as claimed in claim 1 , wherein a difference between the application diameter and the fitting diameter is smaller than or equal to about 70% of a difference between an inner diameter of the outer sleeve and the fitting diameter.

16. The process as claimed in claim 1 , wherein a difference between the application diameter and the fitting diameter is smaller than or equal to about 50% of a difference between an inner diameter of the outer sleeve and the fitting diameter.

17. The process as claimed in claim 1 , wherein during application of said at least one carcass ply onto the building drum, the end flaps of said at least one carcass ply axially project from opposite ends of the outer surface of the building drum.

18. The process as claimed in claim 1 , wherein during application of said at least one carcass ply onto the building drum, the end flaps of said at least one carcass ply are supported on respective rest surfaces extending in a continuation of the outer surface of the building drum.

19. The process as claimed in claim 1 , wherein before the step of applying said at least one carcass ply onto the building drum, application of at least one first component of the carcass sleeve is carried out at the building drum.

20. The process as claimed in claim 19 , wherein said at least one first component is at least partly applied onto respective rest surfaces extending in axially opposite directions in the continuation of the outer surface of the building drum.

21. The process as claimed in claim 1 , further comprising the step of folding down toward a geometric axis of the building drum, the axially-opposite end flaps of the at least one carcass ply applied around the building drum.

22. The process as claimed in claim 21 , wherein:
during application of said at least one carcass ply onto the building drum, the end flaps of said at least one carcass ply are supported on respective rest surfaces extending in a continuation of the outer surface of the building drum; and
the process further comprises the step of removing the rest surfaces before folding down the end flaps of said at least one carcass ply.

23. The process as claimed in claim 1 , wherein the step of engaging each annular anchoring structure comprises:
coaxially fitting the annular anchoring structure around a respective end flap of said at least one carcass ply; and
turning up the end flap of said at least one carcass ply around the respective annular anchoring structure.

24. The process as claimed in claim 1 , wherein the shaping step comprises:
axially approaching the annular anchoring structures; and
radially expanding the carcass sle

Assignees

• Mancini Gianni
• Lo Presti Gaetano
• Pirelli

Inventors

• Mancini Gianni
• Lo Presti Gaetano

Classifications

• B29D30/245 Primary

  Drums for the single stage building process, i.e. the building-up of the cylindrical carcass and the toroidal expansion of it are realised on the same drum (expansion to a toroidal shape B29D30/36) · CPC title

• B29D2030/202

  the building drums being movable, i.e. not permanently connected to a fixed frame · CPC title

• B29D30/26

  Accessories or details, e.g. membranes, transfer rings · CPC title

• B29D30/32 Primary

  Fitting the bead-rings or bead-cores; Folding the textile layers around the rings or cores · CPC title

• B29D2030/3214

  Locking the beads on the drum; details of the drum in the bead locking areas, e.g. drum shoulders · CPC title