Pirelli Pneumatici S.p.a.

Pirelli Coordinamento Pneumatici S.p.a.

Alberto Carra

Luigi Campana

Fabio Montanaro

A method for reducing tire microsliding includes defining a rotation point and rotating a cross section profile about it. A cross section of a radially-external reference profile of a tread band includes a first rectilinear segment near at least one circumferential rib of a first shoulder portion. The first rectilinear segment extends axially outward beyond a corresponding shoulder edge point. A cross section profile of the at least one circumferential rib of the first shoulder portion includes a second rectilinear segment. The rotation point is on the first rectilinear segment, either the corresponding shoulder edge point itself or axially outward of it. The cross section profile of the first rectilinear segment is rotated to define the cross section profile of the second rectilinear segment, so that an axially-inner end of the second rectilinear segment is closer to the carcass structure than an axially-inner end of the first rectilinear segment.

Tyre for medium/heavy transport vehicles

Method of manufacturing tire including rotating rectilinear segment

A tyre for vehicles includes a carcass structure, a belt structure, and a tread. The tread includes a row of central blocks and a row of intermediate blocks arranged on each side of an equatorial plane of the tyre between a central longitudinal groove formed astride the equatorial plane and a pair of longitudinal lateral grooves. The blocks of the central rows are separated from the blocks of the intermediate rows by circumferential sipes and are circumferentially staggered by a first predetermined quantity relative to the blocks of the intermediate rows. Also, the blocks of the central rows arranged on a first side of the equatorial plane of the tyre are circumferentially staggered by a second predetermined quantity relative to the blocks of the central rows on a second side of the equatorial plane of the tyre.

Tire and tread thereof

A vehicle wheel tyre includes a carcass structure, a belt structure, and a tread. The tread includes four circumferential grooves and a plurality of transverse grooves that define at least five circumferential rows of blocks, each block approximating a polygon. The longitudinal sides of the blocks are inclined in the same direction at a predetermined angle to the equatorial plane of the tyre. The blocks of each row are circumferentially staggered relative to the blocks of the next row. The blocks of the central row include stiffening means. Profiles of the front sides of the blocks of the central row are the same as the profiles of the rear of the blocks of the central row rotated through 180&deg;. The blocks of the shoulder rows are elastically linked to the blocks of the intermediate rows.

Motor vehicle tire, particularly for lorries and the like

A tire ( ) having low rolling resistance, in particular for driving wheels of heavy vehicles, comprises a tread ( ) provided with a plurality of transversal grooves ( ) pitchwise spaced from one another and extending in a direction substantially perpendicular to the rolling direction of the tire (D). The grooves ( ) have a reduced depth and are provided with respective slits ( ), extending from a bottom portion ( ) thereof; as such, they contribute to impart to the tire ( ) both the desired low rolling resistance and an adequate traction characteristics during straightaway running.

Tire having low rolling resistance, in particular for driving wheels of heavy vehicles

A tire tread band for medium/heavy duty motor-vehicles having circumferential grooves confining three pairs of respectively center, intermediate and shoulder ribs. Respective tread blocks are defined along the center and intermediate ribs and they are confined by transverse cuts. The center cuts impart a cusp-shaped end conformation and a hollow-shaped end conformation to the respective blocks, and the shapes of said end portions mutually match. The intermediate cuts run in the linear extension of the center cuts to give the respective blocks a rhomboidal configuration. The tire can be alternately associated with a driving axle or a driven axle, by merely reversing its direction of rotation, so that the following results are selectively achieved: an increase in the traction capability by the intermediate blocks or an increase in the directional capability as a result of the mutual wedging between the center blocks at the ground-contacting area.

Growing community of inventors

Milan, Italy

Alberto Carra