Michelin Recherche Et Technique S.a.

Compagnie Generale Des Establissements Michelin - Michelin & Cie

Jos&eacute; Merino Lopez

Pascal Auxerre

Georges Lavialle

Alain Lagnier

Bertrand Garnier De Labareyre

Pascal Falempin

Jean Claude Kaczorwski

A tire with a form ratio H/S between 0.3 and 0.8 has a carcass reinforcement ( ) which is covered radially by a quasi-cylindrical crown reinforcement ( ) and which is tangential at T to a holding circle C. The common tangent at T to the circle C and to the meridian profile of the carcass ( ) makes an angle &agr; of between &plus;20&deg; and &minus;80&deg; with respect to a line parallel to the rotation axis and passing through the tangency point T. In its portion located between the tangency point T and the point E of greatest axial width, the carcass reinforcement ( ) is provided with a reinforcement armature ( ) of circumferentially non-extensible elements. Viewed in meridian cross-section and when the tire is fitted and inflated to the recommended pressure, the carcass ( ) has a meridian profile consisting of four circular arcs configured to improve the endurance of the tire while improving its rolling resistance.

Tire with specified crown reinforcement and carcass profile

A mold for molding a tread, in particular of a tire, having first elements in relief and second elements in relief for cooperating in the molding configuration to form a molding element intended to mold a single cutout opening both on to the running surface of the tread and on to one of the lateral edges of said tread and to define at least one orifice intended to allow the rubber mix to pass during the molding of the tread.

Tread mold

A molding element has an anchoring portion and a molding portion, the anchoring portion being intended to be anchored in a part of a tire tread mold with the molding portion projecting from a molding face of the tire tread mold part. The molding portion of the molding element has at least two extensions, one of these extensions having at least one arm pivotally mounted on the extension. The molding element is characterized in that, in the molding position, at least one arm pivotally mounted on an extension bears on another extension of the same molding element to define at least one orifice passing through the molding element to mold a connecting bridge between opposite walls of a cutout molded by the molding element.

Molding element and mold for molding a cutout in a tread

A tire pattern of a tread intended to be fitted on a tire and including a plurality of elements in relief intended to come into contact with the ground on which the tire fitted with such a tread travels. At least one element in relief having at least one lateral wall undercut relative to the running surface of the tread and provided with at least one incision which opens on to the surface wall of the element in relief and on to at least one undercut lateral wall. So as not to alter the rigidity of said element in relief, in a manner which may be disadvantageous for the performance of a tire fitted with this tread, provision is made that, for levels of wear of the tread between a first depth H and a second depth H , each incision does not cut into the edges or ridges of said element in relief. Also, a mold equipped with molding elements for molding such a tread pattern.

Tread including relief elements having undercut lateral walls and incision that does not cut into ridge

A molding element for a mold for molding a tread, intended to mold in this tread an incision of circular shape around an axis XX&prime;, the main opposing walls of which are connected by a plurality of connecting bridges of rubber mix. This molding element includes two molding parts, each formed by a support extended by at least one molding blade. At least one of the molding parts has a support extended by a blade which is at least partially helical around the axis XX&prime; and mounted freely in rotation around XX&prime; relative to the other molding part. The blades of the molding parts cooperate to define a plurality of orifices intended for molding the connecting bridges. The molding element is characterized in that the molding blades of a first molding part are provided with passages arranged so as to permit the engagement by sliding of the molding blades of the second molding part within the passages to form the molding element in the molding configuration, and in that the support of the second molding part is mounted so as to be mobile in translation relative to the first molding part.

Molding element for tire

A tread is provided with at least one rubber stud of orientation XX&prime; perpendicular or inclined with respect to the tread surface. The rubber stud has a side wall bounded by at least one incision and an outer end wall. The stud is joined to the tread at its base (the rubber stud part located farthest inward on the tread) and by at least one rubber connecting element joining the side wall of said stud to the rest of the tread. The projected length, on the tread surface in new condition and in the direction XX&prime;, of the principal geometrical lines of the surfaces of intersection of all the connecting elements of each rubber stud, represents at least 80 percent of the contour perimeter, measured on the same surface, of each rubber stud. Preferably, the principal geometrical lines bounding the surfaces of intersection of the connecting elements are in the form of helixes around XX&prime;, and the projected length of said lines is equal or close to 100 percent of the perimeter.

Tire tread comprising incisions bounding rubber studs

A molding element designed to mold a cut in a rubber article, such as a tire, and in which the cut has a geometry of rotation on an axis XX&prime;. The molding element has a head extended by a molding part intended to project into the molded surface in order to mold at least one cut in the rubber article. The head is mounted for rotation in a mold member, and the head contains at least one circular cylinder of axis XX&prime; defining the main axis of the molding element, and cooperates with mold member in order to permit a rotation on XX&prime; relative to the mold, when the molding part of the molding element is subjected either to a force acting in direction XX&prime; or to a torque about the same direction XX&prime;.

Growing community of inventors

Riom, France

José Merino Lopez

Growing community of inventors

Riom, France

Jos&eacute; Merino Lopez

José Merino Lopez