Compagnie Generale Des Etablissements Michelin

Michelin Recherche Et Technique S.a.

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Michelin Recherche Et Technique

Michelin Recherche Et Techniques S.a.

Gael Roty

Jose Merino Lopez

Bernard Villeneuve

Anthony Gueugneau

Olivier Muhlhoff

Henri Barguet

Pascal Prost

José Merino Lopez

Hervé Ferigo

Jacky Pineau

Richard Cornille

Khotchakorn Pengsaloong

Ludovic Greverie

Nicolas Dautrey

Sophie Gander

Nanae Shimanaka

Philippe Souyri

Thomas Guy

Michel Deboeuf

Tomoya Sakurada

Xavier Marduel

Sabrina Rih

Laurent Maes

Tomotake Uchida

Yasuhiko Futamura

Yuji Kanno

Jean-Pierre Queslel

The rolling resistance of a tire has been improved without degrading industrial performance. The sidewall () consists of two sub-layers. A first sub-layer (FE) of thickness E1 and volume V1 provides the expected protection functions of a sidewall as the outer wall of the tire, and a second sub-layer of the sidewall (FE) of thickness E2 and volume V2 is optimized at low hysteresis to improve rolling resistance. The ratio V1/(V1+V2) of the volumes of the two sub-layers (FE, FE) is less than or equal to 0.3. The elongation at break of the compound of FEis greater than or equal to 200% measured at a temperature of 100° C., and the viscoelastic loss of the compound of FE, Tan(δ)max, is less than or equal to 0.10.

Tire having optimized performance in terms of rolling resistance without impairing the industrial performance

A tire comprises a sealing layer comprising a junction () extending in a main direction (D) forming, with the circumferential direction (Z) of the tire: in a portion (S) of the sealing layer extending axially in radial line with the working layer, an angle (ES) ranging, in absolute value, from 20° to 60°, and in a portion (F) of the sealing layer extending radially in each sidewall, an angle (EF), in absolute value, strictly greater than the angle (ES) of the main direction (D) of the junction () in the portion (S) of the sealing layer extending axially in radial line with the working layer.

Low-noise tire and method for manufacturing same

Drum () for manufacturing a tire blank, comprising a shaft, two flanges () movable in translation along the shaft, and means for supplying compressed air, each flange comprising at least one pneumatic effector (). At least one flange comprises a first, radially internal ring () and a second, radially external ring () movable in rotation around the first ring by means of at least two airtight pivot connections (), the rings and the pivot connections delimiting at least one sealed chamber (), said flange comprising at least one first compressed-air circulation channel (), a first section () of the first channel belonging to the first ring being connected at one of its ends to the sealed chamber, and a second section () of the first channel belonging to the second ring being connected at one of its ends to the sealed chamber.

Drum and method for manufacturing a tire blank

The molding element has a plurality of contacting element delimited by grooves, the molding element having a molding surface for forming a contact face of the contacting element intended to come into contact with ground during rolling and a groove forming rib portion for forming the groove comprising two opposed rib side faces for forming two opposed groove side faces and a rib top face connecting two rib side faces for forming a groove bottom, the groove forming rib portion providing a space opening to at least one of the rib side faces and/or to the rib top face and an insert being received in the space for forming a portion of the groove and a closing device in the groove, the insert comprises at least one notched plate of thickness t, the notched plate includes at least one notch for forming a flexible fence of the closing device.

Molding element for manufacturing a noise reducing tread

The molding element has a plurality of contacting elements delimited by a plurality of grooves and has a molding surface for forming a contact face and a groove forming rib portion for forming the groove. The groove forming rib portion provides a space opening to one of the rib side faces and/or to the rib top face and an insert that is received in the space for forming a portion of the groove and a closing device in the groove. The insert is composed of thin plates stacked with one another. The forming plate assembly also comprises at notched plates of thickness t, and each notched plate includes a notch for forming a flexible fence, and the notched plate has no area overlapping to the notch in the other notched plated adjacent thereto in sectional view in a direction along which the groove forming rib portion extends.

The tread is provided with a plurality of grooves and/or a plurality of incisions. The tread also has rubber layers laminated in a radial orientation. One rubber layer has a cap rubber layer and a base rubber layer. A modulus G* of the rubber composition constituting the base rubber layer is no more than 2 MPa at &#x2212;10&#xb0; C. with imposed shear stress of 0.25 MPa and is at least 0.7 MPa at 40&#xb0; C. with imposed shear stress of 0.70 MPa. A modulus G* of the rubber composition constituting the cap rubber layer is at least 1 MPa higher than the modulus G* of the the base rubber layer at &#x2212;10&#xb0; C. with imposed shear stress of 0.25 MPa and is less than the modulus G* of the rubber composition at 40&#xb0; C. with imposed shear stress of 0.70 MPa.

Tread made from multi compounds

The disclosure is related to a tread for a tire, this tread having a tread surface intended to come into contact with a roadway and comprising at least one groove of width W and depth P delimited by two facing lateral walls, these lateral walls being connected together by a groove bottom. At least one groove has a plurality of closing devices for reducing the running resonance noise generated by this groove, each closing device comprising at least two sets of flexible blades, a first set is connected to the bottom of the groove and is intended to flex around a first axis, and at least one second set connected to a lateral wall delimiting the groove, this second set being intended to flex around a second axis, this second axis being different than the first axis.

Device for attenuating rolling noise for a tire

A pneumatic tire tread that maintains a good level of water drainage performance up to the final stage of wear of a tread part formed with a plurality of flexible fences which are disposed inside at least one main groove extending from the bottom surface of the main groove and obstructing at least 70% of the cross-sectional area of the main groove, the flexible fences comprising an inside portion having a connecting part which is connected to the main groove, and an outside portion which is radially outside a predetermined height Dfrom the bottom surface of the main groove, and the average angle of inclination of the inside portion with respect to a line perpendicular to the surface of the tread part in contact with the road surface is greater than the average angle of inclination of the outside portion.

Tread for pneumatic tire

Tread having a tread surface intended to come into contact with a road surface and comprising at least one groove of width W and of depth P delimited by two walls facing one another, these walls being joined together by a groove bottom, at least one groove comprising at least one closure device for at least partially closing this groove as it passes through the contact patch, each closure device comprising at least one flexible blade of suitable thickness that allows it to flex under the effect of a circulation of liquid, this at least one flexible blade projecting from the bottom of the groove, each flexible blade being delimited by a contact wall intended to come into contact with the road surface and by end walls each facing a wall delimiting the groove and lateral walls, this tread further comprising at least one passage between the bottom of the groove and each blade of the device, this passage being intended to ensure a minimal flow of water when driving on a water-covered road surface.

Noise-reducing device for a tire

A tread for a pneumatic tire in which air column resonance sound is reduced and wear of the groove fences and tread portion are caused to be approximately the same, while drainage performance is maintained, wherein a plurality of groove fences are formed and are installed within at least one circumferential groove, extending from the bottom of the circumferential groove, and block at least 70% of the cross-sectional area of the circumferential groove, and the bending parameter of the groove fences, defined as E&#xb7;I/(h3l) (where E is the modulus at 10% elongation of the material used for the groove fences, I is the second moment of area of the groove fence, h is the height of the groove fence, and l is the width of the groove fence) is at least equal to 250 Pa and at most equal to 350 Pa.

Pneumatic tire tread

Provided is a pneumatic tire capable of yielding excellent water-draining performance, while reducing air column resonance. This pneumatic tire () has a tread () and at least one ply () arranged toward the interior of the tread in the radial direction. The tread has at least one main channel () and a flexible fence () formed inside the main channel. The main channel has a bottom () and opposing first and second wall surfaces (). The flexible fence extends along the width of the main channel so as to block at least 70% of a cross sectional area of the main channel, and is arranged at intervals so that at least one is present in the main channel in the tread footprint when the tire rolls. A plurality of recesses having an opening that opens in the main channel are formed on the bottom, first wall surface and/or second wall surface of the main channel, the flexible fence being connected to the recess and extending into the main channel via the opening of the recess.

Pneumatic tire

A tread for a tire, this tread having a tread surface intended to come into contact with a road surface and comprising at least one groove of width W and of depth P delimited by two walls facing one another, these walls being joined together by a groove bottom, at least one groove comprising at least one flexible device for at least partially closing this groove as it passes through the contact patch, each flexible device comprising at least one blade of a suitable thickness that allows it to flex under the effect of a circulation of liquid, this blade being borne by a wall delimiting the groove, each blade of thickness E being bounded by a bottom wall facing the bottom of the groove, an end wall facing the other wall of the groove and a contact wall intended to come into contact with the road surface and lateral walls spaced apart by a distance equal to the thickness E of the blade, this tread being such that the bottom wall of the blade comprises a first part referred to as connection part and a second part extending the first part up to the end part of the blade, the connection part being offset towards the outside of the tread with respect to the second part of the bottom wall of the blade so as to form a notch.

Resonant-noise suppressor device for tire

A mold for vulcanizing a tire tread comprising a molding surface able to mold a tread surface of the tread of the tire and at least one bar of length L and of width W able to mold a groove in the tread. The bar comprises two lateral faces extending along the length of the bar and projecting from the molding surface and an upper face connecting the said lateral faces. The mold comprises in the bar at least two cavities respectively opening onto the two lateral faces of the bar without opening onto the upper face of this bar. These cavities overlap in the width of the bar. The mold further comprises a first element added into the bar beforehand, this first element separating the two cavities in the length of the bar.

Growing community of inventors

Clermont-Ferrand, France

Gael Roty