US 11,912,070 B2
Tyre for vehicle wheels
Alfredo Balini, Milan (IT); and Stefano Bizzi, Milan (IT)
Assigned to PIRELLI TYRE S.p.A., Milan (IT)
Appl. No. 16/471,698
Filed by PIRELLI TYRE S.p.A., Milan (IT)
PCT Filed Dec. 22, 2017, PCT No. PCT/IB2017/058342
§ 371(c)(1), (2) Date Jun. 20, 2019,
PCT Pub. No. WO2018/122713, PCT Pub. Date Jul. 5, 2018.
Claims priority of application No. 102016000130965 (IT), filed on Dec. 27, 2016.
Prior Publication US 2019/0315161 A1, Oct. 17, 2019
Int. Cl. B60C 11/12 (2006.01); B60C 11/03 (2006.01)
CPC B60C 11/1218 (2013.01) [B60C 11/0304 (2013.01); B60C 11/0306 (2013.01); B60C 11/1281 (2013.01); B60C 2011/0341 (2013.01); B60C 2011/1209 (2013.01)] 25 Claims
OG exemplary drawing
 
1. A tyre for vehicle wheels, comprising a tread band comprising:
circumferential grooves,
circumferential ribs defined by the circumferential grooves, and
a plurality of sipes extending, on the circumferential ribs, from a radially outer surface of the tread band towards a radially inner portion of the tread band;
wherein the sipes extend along a predetermined trajectory and comprise, in any cross section perpendicular to the predetermined trajectory:
a main portion having a first radial dimension (H′) and a first transversal dimension (T, T′) substantially constant along a radial direction, and a top portion arranged in a radially outer position with respect to the main portion, the top portion extending up to the radially outer surface of the tread band and having, at the radially outer surface of the tread band, a second transversal dimension (W) greater than the first transversal dimension (T, T′);
wherein the sipe further comprises opposite side wall portions extending parallel to one another and that, in any cross section perpendicular to the predetermined trajectory, define the main portion, wherein each of the opposite side wall portions comprises:
first side wall parts extending along a longitudinal direction parallel to the predetermined trajectory, and
second side wall parts that deviate from the longitudinal direction, each of the second side wall parts arranged, along the longitudinal direction, between two successive first side wall parts and defining, in the respective side wall of the sipe, a deformation that defines two mutually interlocking portions in the tread band;
wherein the deformation extends only in the main portion of the sipe and not in the top portion of the sipe,
wherein each of the second side wall parts comprises a first portion and two opposite second portions arranged on opposite sides with respect to the first portion; and
wherein a ratio of the second transversal dimension (W) to the first transversal dimension (T) in a cross section of the sipe taken at the first side wall parts is equal to the ratio of the second transversal dimension (W) to the first transversal dimension (T) in a first cross section of the sipe taken at the first portions of the second side wall parts and smaller than the ratio of the second transversal dimension (W) to the first transversal dimension (T′) in a second cross section of the sipe taken at the second portions of the second side wall parts.
 
25. A tyre for vehicle wheels, comprising a tread band comprising:
circumferential grooves,
circumferential ribs defined by the circumferential grooves, and
a plurality of sipes extending, on the circumferential ribs, from a radially outer surface of the tread band towards a radially inner portion of the tread band;
wherein the sipes extend along a predetermined trajectory and comprise, in any cross section perpendicular to the predetermined trajectory:
a main portion having a first radial dimension (H′) and a first transversal dimension (T, T′) substantially constant along a radial direction, and a top portion arranged in a radially outer position with respect to the main portion, the top portion extending up to the radially outer surface of the tread band and having, at the radially outer surface of the tread band, a second transversal dimension (W) greater than the first transversal dimension (T, T′);
wherein the sipe further comprises opposite side wall portions extending parallel to one another and that, in any cross section perpendicular to the predetermined trajectory, define the main portion, wherein each of the opposite side wall portions comprises:
first side wall parts extending along a longitudinal direction parallel to the predetermined trajectory, and
second side wall parts that deviate from the longitudinal direction, each of the second side wall parts arranged, along the longitudinal direction, between two successive first side wall parts and defining, in the respective side wall of the sipe, a deformation that defines two mutually interlocking portions in the tread band;
wherein the deformation extends only in the main portion of the sipe and not in the top portion of the sipe;
wherein the deformation comprises two opposite first side faces connected through two opposite second side faces, wherein the two opposite second side faces join one to the other at a linear edge (V1) that extends parallel to the predetermined trajectory, wherein the two opposite first side faces are triangle-shaped and the two opposite second side faces are trapezium-shaped.