Process and apparatus for manufacturing pneumatic tyres for vehicle wheels

Patent metadata

Field	Value
Publication number	US-10800122-B2
Application number	US-201715643199-A
Country	US
Kind code	B2
Filing date	Jul 6, 2017
Priority date	Apr 29, 2011
Publication date	Oct 13, 2020
Grant date	Oct 13, 2020

Abstract

In a process for building tyres for vehicle wheels, a carcass sleeve is arranged on a shaping drum including two half-drums and two supports. Each support is operatively associated with one of the half-drums and carries a plurality of turning-up levers having free ends positioned close to the respective half-drum. Two annular anchoring structures are disposed around the carcass sleeve and each of the two supports is locked to the respective half-drum by interposing only stiff mechanical elements in mutual contact between the support and the half-drum. The carcass sleeve is shaped in a toroidal conformation, by setting a threaded shaft in rotation and moving the half-drums close to each other. Subsequently, each of the two supports is unlocked from the respective half-drum and the threaded shaft is set in rotation to move each support close to the respective half-drum and lift up the free ends of the turning-up levers until the end flaps of the carcass sleeve are turned up around the annular anchoring structures.

First claim

The invention claimed is:

1. An apparatus for building a tyre for vehicle wheels, comprising:
a shaping drum comprising:
first and second half drums;
a first support, operatively associated with the first half-drum and a second support operatively associated with the second half-drum, each support carrying a plurality of turning-up levers having free ends positioned close to its respective half drum;
a threaded shaft for axially moving the two supports and the two half-drums in mutually approached or mutually spaced relationship and for lifting the free ends of said turning-up levers through rotation of the threaded shaft; and
two mechanical locking and unlocking devices each interposed between one of the half-drums and its associated support and being configured either in an unlocked position, in which the associated support is movable relative to its half-drum, or in a locked position, in which the associated support is fixed relative to its half-drum, wherein each mechanical locking and unlocking device comprises:
a plurality of guide rods each having a first end integral with a respective one of the half-drums and a second end slidably coupled to the support, associated with the respective one of the half-drums, and
a retaining unit mounted on the support, associated with the respective one of the half-drums, comprising a flange with openings for the second ends of the guide rods and actuators for moving the flange between an engaged position and a disengaged position, wherein in the engaged position the mechanical locking and unlocking device is in the locked position and the second ends of the guide rods are locked on its associated support in first portions of the openings to provide only stiff mechanical elements in mutual contact between the respective half-drum and its associated support, and in the disengaged position the mechanical locking and unlocking device is in the unlocked position and the second ends of the guide rods slide through their associated support in second portions of the openings.

2. The apparatus as claimed in claim 1 , wherein the flange of each mechanical locking and unlocking device is movable in rotation on its associated support between the engaged position and the disengaged position.

3. The apparatus as claimed in claim 1 , wherein the shaping drum comprises:
a shaft carrying the two half-drums and the two supports in a slidable manner; and
a spacer mounted on the shaft and interposed between the first half-drum and the second half-drum, wherein each of the half-drums can be hooked to the spacer for locking the half-drums onto the shaft.

4. The apparatus as claimed in claim 3 , wherein the spacer is interchangeable.

5. The apparatus as claimed in claim 1 , wherein each half-drum has an annular retaining seat for housing a respective bead of the tyre being processed.

6. The apparatus as claimed in claim 5 , wherein each half-drum comprises a plurality of axially internal sectors and a plurality of axially external sectors radially movable for delimiting the respective annular retaining seat.

7. The apparatus as claimed in claim 6 , wherein at least one of the guide rods has an inner channel for passage of a working fluid to control radial movement of either the respective plurality of the axially internal sectors or the respective plurality of the axially external sectors.

8. The apparatus as claimed in claim 6 , wherein the axially external sectors comprise rest tailpieces for the free ends of the turning-up levers.

9. The apparatus as claimed in claim 6 , wherein the axially external sectors comprise inclined surfaces for sliding of the free ends of the turning-up levers.

10. The apparatus as claimed in claim 1 , wherein the shaping drum is a second-stage drum and wherein the apparatus comprises:
a first-stage drum for building of a carcass sleeve; and
a transport device operatively acting between the first-stage drum and the second-stage drum for carrying the carcass sleeve from the first-stage drum to the second-stage drum.

11. The apparatus as claimed in claim 1 , wherein said threaded shaft is coupled to two lead screw nuts, one of the nuts being rigidly connected to a respective one of the supports.

12. The apparatus as claimed in claim 6 , wherein at least one of the guide rods has an inner channel for passage of a working fluid to control radial movement of the respective plurality of the axially internal sectors and the respective plurality of the axially external sectors.

Assignees

• Pirelli

Inventors

• Bigogno Mauro
• Portinari Gianni
• Dale' Pietro

Classifications

• B29D30/24 Primary

  Drums · CPC title

• B29D30/08 Primary

  Building tyres · CPC title

• B29D30/245

  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

• B29D2030/3257

  using pressing rollers · CPC title

• B29D30/12 Primary

  Cores · CPC title