Motorcycle tire

Patent metadata

Field	Value
Publication number	US-10183532-B2
Application number	US-201414230062-A
Country	US
Kind code	B2
Filing date	Mar 31, 2014
Priority date	Apr 11, 2013
Publication date	Jan 22, 2019
Grant date	Jan 22, 2019

Abstract

A motorcycle tire includes a tread portion having a designated rotational direction, the tread portion provided with first inclined grooves extending from a central region to a shoulder region, and second inclined grooves extending from a middle region to the shoulder region. Each first inclined groove includes a first tapered portion, and each second inclined groove includes a second tapered portion. In a pair of the first and second inclined grooves that are arranged closest to each other, the second tapered portion is located behind a forward of the first tapered portion such that a straight line connecting between a forward of the second tapered portion and a backward of the first tapered portion has an angle of from 85 to 90 degrees with respect to a circumferential direction of the tire.

First claim

What is claimed is:

1. A motorcycle tire comprising;
a tread portion having a designated rotational direction,
the tread portion comprising a central region having its center on a tire equator and having a developed width of one third of a tread developed width, a pair of shoulder regions each having a developed width of one sixth of the tread developed width from a tread edge, and a pair of middle regions each between the central region and the middle region,
the tread portion being provided with a plurality of first inclined grooves each extending from the central region to one of the shoulder regions, and a plurality of second inclined grooves each extending from the middle region to the shoulder region between circumferentially adjacent first inclined grooves,
each first inclined groove comprising a main portion, and a first tapered portion having a groove width decreasing toward the rotational direction of the tire,
each second inclined groove comprising a second tapered portion having a groove width decreasing toward the rotational direction of the tire and a narrow portion of locally decreased groove width that is arranged in a longitudinal middle region of the second inclined groove, wherein each second inclined groove comprises a pair of groove edges, each of the pair of groove edges consisting of a pair of adjacent convex curves each arranged to protrude away from a groove centerline of the second inclined groove, and
wherein in a pair of the first and second inclined grooves that are arranged closest to each other, the second tapered portion is located behind a forward end of the first tapered portion in the rotational direction of the tire such that a straight line connecting between a forward end of the second tapered portion and a backward end of the first tapered portion has an angle in a range of from 85 to 90 degrees with respect to a circumferential direction of the tire.

2. The motorcycle tire according to claim 1 , wherein the first inclined grooves extend beyond the tread edge.

3. The motorcycle tire according to claim 1 , wherein the central region, the middle regions, and the shoulder regions have land ratios of Rc, Rm and Rs, respectively, and the land ratios satisfy the following relation:
Rs>Rm>Rc.

4. The motorcycle tire according to claim 1 , wherein the central region, the middle regions, and the shoulder regions have land ratios of Rc, Rm and Rs, respectively, and the land ratios Rc, Rm and Rs are set in a range of from 0.8 to 0.9.

5. The motorcycle tire according to claim 1 ,
wherein the first tapered portion of the first inclined groove has a length larger than a maximum groove width of the first tapered portion, and
the second tapered portion of the second inclined groove has a length larger than a maximum groove width of the second tapered portion.

6. The motorcycle tire according to claim 1 ,
wherein the first inclined grooves comprise a left first inclined groove, and a right first inclined groove, each having the first tapered portion in the vicinity of the tire equator, and
the tread portion is further provided with a circumferentially extending central longitudinal groove disposed between the left first inclined groove and the right first inclined groove.

7. The motorcycle tire according to claim 1 , wherein a tread pattern of the tread portion comprises a left pattern, and a right pattern, the left pattern has a symmetrical design of the right pattern with respect to the tire equator, and the left pattern is arranged to be shifted with respect to the right pattern in a circumferential length of the tire.

8. A motorcycle tire comprising:
a tread portion having a designated rotational direction, the tread portion comprising a central region having its center on a tire equator and having a developed width of one third of a tread developed width, a pair of shoulder regions each having a developed width of one sixth of the tread developed width from a tread edge and a pair of middle regions each between the central region and the middle region;
the tread portion provided with a plurality of first inclined grooves each extending from the central region to one of the shoulder regions, and a plurality of second inclined grooves each extending from the middle region to the shoulder region between circumferentially adjacent first inclined grooves;
each first inclined groove comprising a main portion and a first tapered portion having a groove width decreasing toward the rotational direction of the tire;
each second inclined groove comprising a second tapered portion having a groove width decreasing toward the rotational direction of the tire and a narrow portion of locally decreased groove width and that is arranged in a longitudinal middle region of the second inclined groove, wherein only a single narrow groove is connected to the respective second inclined groove; and
in a pair of the first and second inclined grooves that are arranged closest to each other, the second tapered portion being located behind a forward end of the first tapered portion in the rotational direction of the tire such that a straight line connecting between a forward end of the second tapered portion and a backward end of the first tapered portion has an angle in a range of from 85 to 90 degrees with respect to a circumferential direction of the tire.

9. The motorcycle tire according to claim 8 , wherein the narrow groove is in communication with the narrow portion of the second inclined groove.

10. The motorcycle tire according to claim 8 , wherein the narrow groove has the other end terminated without communicating with any other groove.

11. The motorcycle tire according to claim 8 , wherein the at least one narrow groove extends in an arc fashion.

12. The motorcycle tire according to claim 8 , wherein the narrow groove protrudes toward the tire equator, and wherein each first inclined groove is curved to protrude in a same direction as the narrow groove.

Assignees

• Sumitomo Rubber Ind

Inventors

• Matsunami Toshiyuki
• Yoshida Yumiko

Classifications

• B60C2011/0381

  Blind or isolated grooves · CPC title

• B60C11/0302 Primary

  directional pattern, i.e. with main rolling direction · CPC title

• B60C2011/0376

  characterised by width · CPC title

• B60C11/033

  by the void or net-to-gross ratios of the patterns · CPC title

• B60C2011/0374

  Slant grooves, i.e. having an angle of about 5 to 35 degrees to the equatorial plane · CPC title