Process and apparatus for building tyres

Patent metadata

Field	Value
Publication number	US-2017190130-A1
Application number	US-201715463431-A
Country	US
Kind code	A1
Filing date	Mar 20, 2017
Priority date	May 28, 2008
Publication date	Jul 6, 2017
Grant date	—

Abstract

A carcass ply is applied around an outer surface of a building drum according to an application diameter larger than the fitting diameter of a tyre. Coaxially engaged around each of the end flaps is an annular anchoring structure defining the fitting diameter. A pair of sidewalls is manufactured by laying of a continuous elongated element in the form of approached coils on the carcass sleeve. An outer sleeve, including at least one belt structure possibly associated with a tread band, is coaxially centered around the carcass sleeve. 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

1 . An apparatus for building a tyre, comprising:
a building drum comprising two axially approachable halves and having an outer circumferential surface defining an application diameter; devices for applying at least one carcass ply having axially opposite end flaps around an outer circumferential surface of the building drum; devices for engaging an annular anchoring structure with a fitting diameter smaller than said application diameter coaxially around each of the end flaps of said at least one carcass ply, so as to make a carcass sleeve; devices for forming at least one pair of sidewalls around the carcass sleeve, by laying of at least one first continuous elongated element in the form of approached coils; at least one pair of auxiliary support members, each having at least one circumferential rest surface extending in a continuation of the outer circumferential surface of the building drum to support at least the axially opposite end flaps of said at least one carcass ply, being removably engaged with the building drum, and being in axially approached relationship with a respective half of the building drum, wherein each auxiliary support member is removably engaged with the building drum at least at a connecting member carried by the building drum, wherein each connecting member is in the form of a cylindrical sleeve; and at least one pair of auxiliary shaping members capable of being removably engaged with the building drum by a fastening device operatively carried by a flanged element of each auxiliary shaping member, each auxiliary shaping member being capable of being connected at least to a respective one of said connecting members in place of each auxiliary support member, the fastening device comprising a guide sleeve internally defining an engagement seat capable of slidably engaging on a cylindrical surface of the cylindrical sleeve of the respective one of said connecting members, each auxiliary shaping member having a continuous circumferential extension to hermetically seal the carcass sleeve at the annular anchoring structures thereby facilitating radial expansion of the sleeve itself through inflation during the shaping and maintenance of the inflated state following the shaping.

2 . The apparatus as claimed in claim 1 , further comprising devices for disengaging said auxiliary support members from the building drum.

3 . The apparatus as claimed in claim 1 , wherein the building drum further comprises a central section capable of slidably engaging said halves and defining a central section of said outer circumferential surface.

4 . An apparatus as claimed in claim 1 , wherein each auxiliary shaping member comprises at least one flanged element capable of being removably fastened in axially approached relationship with a respective half of the building drum, and carrying at least one sealing ring designed to act against a respective circumferential abutment edge carried by the building drum.

5 . The apparatus as claimed in claim 4 , wherein each auxiliary shaping member further comprises thrust devices capable of operating between the flanged element and the sealing ring to push the sealing ring toward the circumferential abutment edge.

6 . The apparatus as claimed in claim 1 , wherein each auxiliary shaping member comprises a plurality of sealing rings which are respectively concentric and have respective different diameters.

7 . The apparatus as claimed in claim 1 , further comprising devices designed to locate an outer sleeve comprising a belt structure at a coaxially centered position around the carcass sleeve formed on the building drum.

8 . The apparatus as claimed in claim 7 , further comprising at least one auxiliary drum as well as devices for forming said outer sleeve by laying of elementary components on the auxiliary drum.

9 . The apparatus as claimed in claim 7 , further comprising devices for forming a tread band by laying of at least one second continuous elongated element into coils disposed in approached relationship at a radially external position around the belt structure.

10 . The apparatus as claimed in claim 9 , wherein the devices for forming the tread band comprise members for forming axially opposite end portions of the tread band by laying of at least one third continuous elongated element.

11 . The apparatus as claimed in claim 10 , wherein said third continuous elongated element has a same composition as that of said at least one first continuous elongated element used for manufacture of respective sidewalls.

12 . The apparatus as claimed in claim 1 , wherein devices for making said at least one carcass ply carry out laying of elementary components on the building drum.

13 . The apparatus as claimed in claim 1 , wherein devices for making said at least one carcass ply carry out laying of a plurality of strip-like elements disposed in succession along a circumferential extension of the outer circumferential surface of the building drum.

Assignees

• Pirelli

Inventors

• Marchini Maurizio
• Lo Presti Gaetano
• Mancini Gianni
• Misani Pierangelo

Classifications

• B29D2030/726

  Decorating or marking the sidewalls before tyre vulcanization · CPC title

• B29D2030/2614

  Bladders associated with the building drum, e.g. bladders used for the toroidal expansion, bladders for turning-up the plies · CPC title

• B29D30/32

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

• 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

• B29D30/26

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