Michelin Recherche Et Technique S.a.

Compagnie Generale Des Etablissements Michelin

Societe Detechnologie Michelin

Compagnie Generale Des Etablissments Michelin

Richard Audigier

Stéphane Oraison

Fabien Marlier

Mathieu Vandaele

Stéphanie Cambon

Christophe Bessac

Jean-Denis Hidrot

Christelle Chaulet

Chris Boyer

Pascal Falempin

Gilles Douet

Tire for a heavy goods vehicle comprising a tread of total thickness E and total volume V, having a tread surface intended to come into contact with a roadway, at least one cavity or groove that is continuous in a main direction, and delimited by side walls connected by a bottom, a cross section, the points furthest towards the inside of the bottom of each cavity defining a bottom line, wherein each cavity or groove comprises a plurality of open sections open onto the tread surface in the new state and a plurality of closed sections, connected to the open sections being arranged in alternation, each closed section being spaced away from the tread surface by a bridge of rubber, wherein the points on the bottom line of said cavity or groove lie at distances between a minimum distance Dm and a maximum distance DM with respect to the tread surface, the bottom line of each cavity or groove following a wavy geometry of positive amplitude equal to the difference (DM&#x2212;Dm).

Tread including at least one wavy groove, and method for producing same

A tire for a heavy goods vehicle, having a tread having a tread surface provided in the new state with at least one groove delimited by opposing side walls, this groove opening onto the tread surface in a discontinuous manner by way of a plurality of portions that are open towards the exterior of the tread, these open portions having two ends that are extended under the tread surface by channels having inlets connected to the ends of the open portions, these inlets to the channels having a mean surface area S. This tread is such that each open portion on the tread surface is provided at each of its ends with a closure device for partially closing the cross section of the inlets to the channels when the tire is running and for leaving a passage unclosed.

Device for protecting a groove in a tread

Tread for a tire for a heavy goods vehicle of total thickness E and of total volume V, having at least one continuous groove comprising: at least two wearing layers in the thickness of the tread, each having a thickness at most equal to 75% of the total thickness E of the tread, a plurality of external cavities and a plurality of internal cavities positioned radially and entirely on the inside of the tread surface in the new state, each internal cavity being connected to an external cavity by a connecting channel, and having a total voids volume Vc at least equal to 7% and at most equal to 12% of a volume equal to the sum of the total volume V and of the total voids volume, and having an effective voids volume Ve for each wearing layer less than the total voids volume Vc, and satisfying the equation: 0.4 St&#x3c;Ve&#x3c;0.8 St, wherein 0.4 and 0.8 are heights in millimeters and St is the surface delimited by the external contour of the contact patch under static conditions under service load and pressure, and at least the first wearing layer I is made up of a rubber compound based on at least one material having a dynamic Tg higher than &#x2212;40&#xb0; C. and predominantly containing a SBR copolymer of Tg&#x3e;&#x2212;65&#xb0; C.

Tread for heavy goods vehicle tire

Tire tread having at least two wearing layers, provided with at least one continuous groove having in the as new condition a plurality of external cavities opening onto the tread surface and a plurality of internal cavities placed radially and completely inside the tread surface, such that: the difference between the mean lengths of the internal cavities and of the external cavities is at most equal to 20% of the longest mean length, the difference in the mean cross-sectional areas of the internal and external cavities is at most equal to 20% of the largest mean area, each external cavity of a continuous groove being connected to at least two internal cavities of the same groove and having a plurality of incisions opening onto the tread surface, each connecting two consecutive external cavities of the same groove and at least two connecting channels and at least one internal cavity.

Tire tread having improved rigidity

A tire comprising a crown reinforcement which is itself capped radially with a tread, the crown reinforcement containing at least one layer of circumferential reinforcing elements distributed axially at a variable pitch. The layer of circumferential reinforcing elements comprising five parts, these being a central part, two intermediate parts and two axially exterior parts, the pitch in the central part being in the range between 1 and 1.5 times the pitch of the axially exterior parts and the pitch in an intermediate part being in the range between 1.6 and 2 times the pitch of the axially exterior parts.

Tire for heavy vehicles, with a crown reinforcement comprising at least one layer of circumferential reinforcing elements

Portion of a pneumatic tire

Pneumatic tire

Growing community of inventors

St-Laure, France

Richard Audigier