Abstract:
An assembly (1) formed of a wheel comprising a rim (3) equipped with an inflation valve (4), a tire (2) mounted on said rim (3) of said wheel, and a foam insert (5) placed inside the volume defined by the internal wall of the tire (2) and the wheel rim (3). The foam insert (5) is disposed in a first compartment (A) in communication with the atmosphere via a duct (36) and isolated in airtight manner by a flexible membrane (51) from the rest of the space (B) inside the tire casing, which space forms a second compartment (B) in communication with the inflation valve (4, 41) and designed to be inflated to the utilisation pressure of the tire. At least one of the edges of the membrane (52a, 52b) forms an airtight joint with the rim (3) along a circular bearing surface (32a, 32b), separate from the rim seats (31a, 31b) designed to receive the beads (21a, 21) of the tire (2), and situated axially inside the space between each of the seats (31a, 31b) and the sidewall of the foam insert (50a, 50b) positioned opposite said seat.
Abstract:
A rubber article, such as a tire, composed of at least two rubber mixes with different composition and properties, the said two mixes having a lap joint characterized in that at least one edge of at least one of the two mixes has an end with an oscillatory trace-line.
Abstract:
A process for cross-linking/expanding at least one cross-linkable, expandable blank, which is intended to form all or part of an elastomeric safety support for a tire in which: the cross-linking consists of curing the expandable or expanded blank in a bath of fluid at excess pressure which is contained in an enclosure, such that the blank interacts with the bath independently of the enclosure, the temperature of the bath having a maximum value of between 110° C. and 210° C. and the absolute pressure of said bath having at least a value equal to or greater than 14 bar, and the expansion consists of curing the cross-linkable or cross-linked blank in the bath, the temperature of the bath having a maximum value of between 110° C. and 210° C., and the absolute pressure of the bath having at least a value equal to or greater than 5 bar and a final pressure-relief value substantially equal to 1 bar, for expanding the blank such that its increase in volume is unlimited with respect to the enclosure.
Abstract:
A safety support for mounting on a rim inside a tire fitted on a vehicle to support a tread of the tire in the event of a loss of inflation pressure. The safety support includes a substantially cylindrical base configured to conform to the rim. The support further includes a crown with a radially outer wall configured to enter into contact with an internal wall of a crown of the tire in the event of a loss of pressure and to leave clearance therebetween at the rated operating pressure of the tire. The safety support further includes an annular body linking the base and the crown of the support. An envelope of the radially outer wall of the support crown is defined, when the support is mounted on the rim, with f being the deflection undergone by the support mounted on the rim under a load Z, the rated load of the tire, the envelope being confined between two cylinders of revolution of radius Rmax and Rmin satisfying the following relationship: 0.2f
Abstract:
A process for cross-linking/expanding at least one cross-linkable, expandable blank, which is intended to form all or part of an elastomeric safety support for a tire in which: the cross-linking consists of curing the expandable or expanded blank in a bath of fluid at excess pressure which is contained in an enclosure, such that the blank interacts with the bath independently of the enclosure, the temperature of the bath having a maximum value of between 110° C. and 210° C. and the absolute pressure of said bath having at least a value equal to or greater than 14 bar, and the expansion consists of curing the cross-linkable or cross-linked blank in the bath, the temperature of the bath having a maximum value of between 110° C. and 210° C., and the absolute pressure of the bath having at least a value equal to or greater than 5 bar and a final pressure-relief value substantially equal to 1 bar, for expanding the blank such that its increase in volume is unlimited with respect to the enclosure.