Tire

Patent metadata

Field	Value
Publication number	US-2024123767-A1
Application number	US-202318379172-A
Country	US
Kind code	A1
Filing date	Oct 12, 2023
Priority date	Oct 14, 2022
Publication date	Apr 18, 2024
Grant date	—

Abstract

A tire includes a tread. The tread can include a cap portion and a base portion. The cap portion can include an outer cap portion on an outer side in a width direction of a vehicle when the tire is mounted to the vehicle, and an inner cap portion on an inner side in the width direction of the vehicle when the tire is mounted to the vehicle. A 300% modulus of the inner cap portion can be not less than 5.0 MPa. A 300% modulus of the outer cap portion can be higher than the 300% modulus of the inner cap portion, and can be not greater than 9.0 MPa. A first shoulder land portion can include a boundary between the outer cap portion and the inner cap portion.

First claim

What is claimed is:

1 . A tire comprising a tread extending in a circumferential direction and having an outer circumferential surface that is a tread surface, wherein
the tread has a plurality of circumferential grooves aligned in an axial direction and dividing the tread into a plurality of land portions, the plurality of circumferential grooves include a first shoulder circumferential groove on an outer side in a width direction of a vehicle when the tire is mounted to a vehicle, and a second shoulder circumferential groove on an inner side in the width direction of the vehicle when the tire is mounted to the vehicle, the land portion outward of the first shoulder circumferential groove in the axial direction is a first shoulder land portion, the land portion outward of the second shoulder circumferential groove in the axial direction is a second shoulder land portion, the tread includes a cap portion to come into contact with a road surface, and a base portion radially inward of the cap portion and covered with the cap portion, the cap portion includes an outer cap portion on the outer side in the width direction of the vehicle, and an inner cap portion on the inner side in the width direction, a 300% modulus of the inner cap portion is not less than 5.0 MPa, a 300% modulus of the outer cap portion is higher than the 300% modulus of the inner cap portion, and is not greater than 9.0 MPa, and the first shoulder land portion includes a first boundary between the outer cap portion and the inner cap portion.

2 . The tire according to claim 1 , wherein
a first end, on the tread surface side, of the first boundary between the outer cap portion and the inner cap portion is a first boundary end, a second end, on the base portion side, of the first boundary is a second boundary end, the first shoulder circumferential groove includes a groove bottom, an outer groove wall on an outer side in the axial direction, and an inner groove wall on an inner side in the axial direction, a second boundary between the groove bottom and the outer groove wall is a reference position of the first shoulder circumferential groove, a distance in the axial direction from the reference position of the first shoulder circumferential groove to the first boundary end is not less than 3 mm, and a ratio of the distance in the axial direction to a ground-contact width of the first shoulder land portion is not greater than 20%.

3 . The tire according to claim 1 , wherein, in a meridian cross-section of the tire, a distance in the axial direction from an equator plane to the first boundary between the outer cap portion and the inner cap portion gradually increases from the first boundary end toward the second boundary end.

4 . The tire according to claim 3 , wherein, in the meridian cross-section of the tire, an angle formed between a straight line passing through the first boundary end and the second boundary end and a tangent line tangent to the tread surface at the first boundary end is not less than 5 degrees and not greater than 80 degrees.

5 . The tire according to claim 1 , wherein the 300% modulus of the outer cap portion is not less than 8.0 MPa.

6 . The tire according to claim 1 , wherein the 300% modulus of the inner cap portion is not greater than 7.0 MPa.

7 . The tire according to claim 1 , wherein a ratio of the 300% modulus of the outer cap portion to the 300% modulus of the inner cap portion is not less than 1.1.

8 . The tire according to claim 1 , wherein, in a meridian cross-section of the tire, a contour line of the first boundary between the outer cap portion and the inner cap portion is curved toward the base portion side.

9 . The tire according to claim 2 , wherein, in a meridian cross-section of the tire, positions of the first boundary end and the second boundary end coincide with each other in the axial direction.

10 . The tire according to claim 1 , wherein the first shoulder circumferential groove extends in the inner cap portion in a radial direction without extending into the outer cap portion or the base portion.

11 . The tire according to claim 1 , wherein
a first end, on the tread surface side, of the first boundary between the outer cap portion and the inner cap portion is a first boundary end, a second end, on the base portion side, of the first boundary is a second boundary end, the first boundary end is at the tread surface, and the second boundary end is at an interface between the base portion and the cap portion.

12 . The tire according to claim 1 , wherein
the outer cap portion is formed of a first crosslinked rubber, and the inner cap portion is formed of a second crosslinked rubber different from the first crosslinked rubber.

13 . The tire according to claim 1 , wherein
the first shoulder circumferential groove includes a groove bottom, an outer groove wall on an outer side in the axial direction, and an inner groove wall on an inner side in the axial direction, and a first angle of the outer groove wall is greater than a second angle of the inner groove wall.

14 . The tire according to claim 1 , wherein
a first end, on the tread surface side, of the first boundary between the outer cap portion and the inner cap portion is a first boundary end, the first shoulder circumferential groove includes an outer groove wall on an outer side in the axial direction and an inner groove wall on an inner side in the axial direction, and the first boundary end is spaced apart from the outer groove wall at the tread surface.

15 . The tire according to claim 1 , wherein
a first end, on the tread surface side, of the first boundary between the outer cap portion and the inner cap portion is a first boundary end, a second end, on the base portion side, of the first boundary is a second boundary end, and the first boundary extends linearly continuously from the first boundary end to the second boundary end.

16 . A tire comprising a tread extending in a circumferential direction and having an outer circumferential surface that is a tread surface, wherein
the tread has a plurality of circumferential grooves aligned in an axial direction and dividing the tread into a plurality of land portions, the plurality of circumferential grooves include a first shoulder circumferential groove on a first side in the axial direction, and a second shoulder circumferential groove on a second side in the axial direction, the land portion outward of the first shoulder circumferential groove in the axial direction is a first shoulder land portion, the land portion outward of the second shoulder circumferential groove in the axial direction is a second shoulder land portion, the tread includes a cap portion to come into contact with a road surface, and a base portion radially inward of the cap portion and covered with the cap portion, the cap portion includes an outer cap portion on the outer side in the width direction of the vehicle, and an inner cap portion on the inner side in the width direction, a 300% modulus of the inner cap portion is not less than 5.0 MPa, a 300% modulus of the outer cap portion is higher than the 300% modulus of the inner cap portion, and is not greater than 9.0 MPa, the first shoulder land portion includes a first boundary between the outer cap portion and the inner cap portion, a first end, on the tread surface side, of the first boundary between the outer cap portion and the inner cap portion is a first boundary end, a second end, on the base portion side, of the first boundary is a second boundary end, the first sh

Assignees

• Sumitomo Rubber Ind

Inventors

• Okabayashi Shiho

Classifications

• B60C2011/013

  provided with a recessed portion · CPC title

• B60C2011/0341

  Circumferential grooves · CPC title

• B60C2011/0025

  Modulus or tan delta · CPC title

• B60C11/0008

  characterised by the tread rubber · CPC title

• B60C11/01

  Shape of the shoulders between tread and sidewall, e.g. rounded, stepped or cantilevered · CPC title