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EP-4735274-A1 - TYRE

EP4735274A1EP 4735274 A1EP4735274 A1EP 4735274A1EP-4735274-A1

Abstract

The present invention relates to a tyre comprising a plurality of lateral grooves (23), two sidewalls comprising a series of projections (28) alternating with voids (29), each of the projections comprising an upper face (281) spaced away from the sidewall (26) and at least three lateral faces (282) extending from the sidewall to the upper face (281) and, with an imaginary straight line indicating a centre of the void being inclined by an angle A, the lateral face (282) extending substantially parallel to the outer axial end of the tread being situated so as to completely cross an imaginary extension of the lateral groove (23), and the lateral faces (282) of circumferentially adjacent projections (28) having an overlap in the radial direction. The circumferential width wp of each projection (28) is at least equal to 150% of the width W of the corresponding lateral groove (23) and at most equal to 110 mm.

Inventors

  • IMAIZUMI, TAKASHI
  • SUGAWARA, TAKASHI

Assignees

  • COMPAGNIE GENERALE DES ETABLISSEMENTS MICHELIN

Dates

Publication Date
20260506
Application Date
20240530

Claims (7)

  1. 1. A tire (1) for a rolling assembly comprising a rim and a tire, the tire (1) comprising a tread (2) intended to come into contact with the ground during rolling via a contact face (25) and comprising two outer axial ends, the tread (2) comprising a plurality of lateral grooves (3) of width W opening onto both the contact face (25) and one of the two outer axial ends of the tread (2) and extending generally in the axial direction of the tire (1), the tread (2) being connected, via two sidewalls (6), to two bead regions intended to be fitted onto the rim, at least one sidewall (6) comprising, on its outer surface, a series of projections (8) each having a circumferential width wp and a radial length Ip, alternating circumferentially with voids (9) of a circumferential width wv, each of the projections (8) being spaced radially inwardly from the outer axial end of the tread (2) by a radial distance D, each of the projections (8) having an upper face (81) spaced from the sidewall surface (6) by a minimum height hpm which is greater than a height of any character and/or design molded on the sidewall (6) other than the projections (8) and by a maximum height hpx, at least three side faces (82) extending from the sidewall surface (6) to the upper face (81), one of the at least three side faces (82) located radially closest to the tread (2) extending substantially parallel to the respective one of the two outer axial ends of the tread (2), an imaginary straight line indicating a center of the void (9) being inclined at an angle A to the radial direction, the tire being characterized in that the side face (82) of the projection (8) located radially closest to the tread (2) of the tread (2) extending substantially parallel to the respective one of the two outer axial ends of the tread (2) is located so as to completely intersect an imaginary extension VEL of at least one of the plurality of lateral grooves (3), in that the lateral faces (82) of circumferentially adjacent projections (8) forming the void (9) have an overlap in the radial direction, and in that the circumferential width wp is at least equal to 150% of the width W of the corresponding lateral groove (3) and at most equal to 110 mm.
  2. 2. A tire according to the preceding claim, in which the maximum height hpx of the projection (8) is between 1.0 mm and 8.0 mm inclusive.
  3. 3. A tyre according to any preceding claim, wherein the angle A of the imaginary straight line indicating the centre of the void (9) is between 15° and 75° inclusive.
  4. 4. A tire according to any one of the preceding claims, in which the radial distance D is at least equal to 2.0 mm and at most equal to 7.0 mm.
  5. 5. A tire according to any one of the preceding claims, in which the radial length Ip of the projection (8) is at least equal to 20 mm and at most equal to 70 mm.
  6. 6. A tire according to any preceding claim, wherein the circumferential width wv of the void (9) is at least 5.0 mm and at most 15.0 mm, and wherein a degree of circumferential overlap between two circumferentially adjacent projections (8) is at least 4% and at most 15% of the circumferential width wp of the projection (8).
  7. 7. A tire according to any one of the preceding claims, in which the projection (8) comprises an extension portion (83) extending radially inwards from the lateral face (82) oriented radially inwards.

Description

Pneumatic [001] The present invention relates to a pneumatic tire. The invention relates, in particular, to a tire sidewall portion design intended to improve endurance performance, with an aesthetically appealing design, while maintaining comfort performance. [002] In recent years, there has been an increase in the number of TTL (recreational off-road) vehicles. A TTL tire is often intended to be driven primarily on paved roads, but must also have an appropriate level of off-road performance. A tire is known to have projections on a sidewall portion that does not normally come into contact with the ground except when traveling off-road, thereby providing adequate off-road performance. The projections also make the tire aesthetically appealing. [003] Document JP2004291936 discloses a pneumatic tire comprising a pair of bead wires, a carcass wrapped around the bead wires and formed into a toroidal shape, belt layers provided on the outside, in a radial direction of the tire, of a crown portion of the carcass, and a tread rubber provided on the outside, in the radial direction of the tire, relative to the belt layers, wherein a plurality of projections having a height of 5 mm or more are provided on a shoulder portion in a spaced manner in a peripheral direction of the tire R, and the area of a lower surface of the projection is such that it is at least twice the area of an upper surface of the projection. [004] Document JP2004291937 discloses a pneumatic tire comprising a pair of bead cores, a carcass, belt layers and a tread rubber, a plurality of protrusions having a height of 5 mm or more being provided on a shoulder portion spaced apart in a peripheral direction of the tire R, one or a plurality of ribs connecting the protrusions being provided between adjacent protrusions, the height of the rib being 50 to 100% of the height of the protrusion, the length, in a radial direction of the tire A, being increased from an upper surface of the rib to a lower surface, and the total sum of the lengths, in the radial direction of the tire A, of the lower surfaces of the ribs between adjacent protrusions being such that it is at least 40% of the length, in the radial direction of the tire A, of an upper surface of the protrusion. [005] Document US20190315164 discloses a tire comprising a projection on a shoulder portion. The projection includes a side wall projecting from a surface of the shoulder portion, and an upper wall provided at a distal end of the side wall. The side wall includes portions facing each other in a circumferential direction of the tire. Each of the portions is inclined in the circumferential direction of the tire such that a projection height which is a distance of the projection relative to the surface of the shoulder portion gradually decreases from the upper wall toward the surface of the shoulder portion. An inclination angle of each of the portions in the circumferential direction of the tire relative to the surface of the shoulder portion gradually decreases from the inside to the outside in the radial direction of the tire. [006] Document US20190193477 discloses a pneumatic tire comprising a pair of bead portions, a pair of sidewall portions, a tread portion, a plurality of lug grooves extending from a shoulder region of the tread portion to a shoulder region of the sidewall portion, and a block defined by the plurality of lug grooves, the block comprising a shoulder block formed in the shoulder portion and a shoulder block formed in the shoulder portion, at least some of the plurality of lug grooves terminating at a connecting portion connecting each pair of shoulder blocks, the connecting portion being provided on an inner side, in the tire diametrical direction, of a point corresponding to 50% of the length, in the tire diametrical direction, of the shoulder block from an upper end point of the shoulder block, a platform or projection being formed at the location where the shoulder block shoulder has the maximum raised height at the tire diametric location of the connecting part. [007] Document US20210170805 discloses a pneumatic tire comprising a first platform portion which is formed on a sidewall portion, protrudes toward an outer side in a tire width direction, and extends in a tire circumferential direction over the entire circumference of the tire, and a plurality of second platform portions which are formed in a central portion, in a tire radial direction, of the first platform portion, protrude toward an outer side in the tire width direction, extend in the tire circumferential direction, and are mutually spaced apart in the tire circumferential direction. [008] Document US20190077198 discloses a tire comprising a sidewall region extending in a radial direction of the tire, the sidewall region comprising a plurality of protruding regions that protrude in a width direction of the tire, one dimension, in a circumferential direction of the tire, and the sidewall region comprisi