# US 10,245,894 B2 · Pneumatic tire > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,245,894 B2 - Document ID: US10245894B2 - Status: Granted - Kind: B2 - Application number: 15/313,532 - Filed: 2015-05-20 - Published: 2017-06-29 - Granted: 2019-04-02 - Earliest claimed: 2014-05-26 - Assignees: The Yokohama Rubber Co., Ltd. - Applicants: The Yokohama Rubber Co., LTD. - Inventors: Yuta Uchida - Web page: https://patentgrep.com/patent/US10245894B2 ## CPC - B60C 11/042: {further characterised by the groove cross-section} - B60C 11/03: Tread patterns - B60C 11/0304: {Asymmetric patterns} - B60C 11/1376: {Three dimensional block surfaces departing from the enveloping tread contour} - B60C 11/1392: {with chamfered block edges} - B60C 11/04: in which the raised area of the pattern consists only of continuous circumferential ribs, e.g. zig-zag (B60C11/12, B60C11/13 take precedence) - B60C 2011/0025: {Modulus or tan delta} - B60C 2011/013: {provided with a recessed portion} - B60C 2011/0341: {Circumferential grooves} - B60C 2011/0383: {at the centre of the tread} - B60C 2011/0388: {provided at the equatorial plane} - B60C 2011/039: {provided at the shoulder portion} - B60C: VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES ## Abstract A pneumatic tire includes at least three circumferential grooves extending in the tire circumferential direction in the tread portion, and at least four ribs extending in the tire circumferential direction. In the pneumatic tire, at least two of the ribs including a rib disposed on a first side of the tire equatorial plane in the tire width direction and a rib disposed on a second side protrude to the outer side in the tire radial direction beyond a profile line of a tread surface when viewed in a meridian cross section. The protruding amount decreases in order from the first side to the second side in the tire width direction, and the loss tangent tan δ at 60° C. of the compound in a region where the rib has the least protruding amount is smaller than that in a region of the rib where the protruding amount is the greatest. ## Claims ### Claim 1 A pneumatic tire comprising: at least four ribs extending in a tire circumferential direction, defined and formed by at least three circumferential grooves extending in the tire circumferential direction in a tread portion thereof, at least two of the at least four ribs including one of the at least four ribs disposed on a first side of a tire equatorial plane in a tire width direction and another one of the at least four ribs disposed on a second side thereof, at least three of the at least four ribs protruding to an outer side in a tire radial direction beyond a profile line of a tread surface when viewed in a meridian cross section, the protruding amounts of the at least three of the at least four ribs decreasing in order from the first side towards the second side in the tire width direction, a cap tread forming a tread surface of the tread portion is composed from different types of compounds, and a loss tangent tan δ at 60° C. of one of the compounds in a region where the rib has the least protruding amount is smaller than a loss tangent tan δ of another one of the compounds in a region of the rib where the protruding amount is the greatest, the ribs protruding beyond the profile line are provided adjacent to one another interposed by one of the circumferential grooves, and the difference between the protruding amounts of the adjacent ribs is from 0.4 mm to 0.8 mm, both inclusive. ### Claim 2 (depends on 1) The pneumatic tire according to claim 1, wherein the protruding amount from the profile line of each of the at least three of the at least four ribs is from 0.05 mm to 2.0 mm, both inclusive. ### Claim 3 (depends on 2) The pneumatic tire according to claim 2, wherein the loss tangent tan δ at 60° C. of the compound in the region where the rib has the greatest protruding amount is from 0.25 to 0.4, both inclusive, and the loss tangent tan δ in the region of the rib where the protruding amount is the least is from 0.2 to 0.33, both inclusive. ### Claim 4 (depends on 3) The pneumatic tire according to claim 3, wherein a vehicle inner/outer side orientation when mounted to a vehicle is designated, the protruding amounts decreases in order from the vehicle outer side to the vehicle inner side, and the loss tangent tan δ at 60° C. of the compound is smaller on the vehicle inner side than the vehicle outer side. ### Claim 5 (depends on 2) The pneumatic tire according to claim 2, wherein a vehicle inner/outer side orientation when mounted to a vehicle is designated, the protruding amounts decreases in order from the vehicle outer side to the vehicle inner side, and the loss tangent tan δ at 60° C. of the compound is smaller on the vehicle inner side than the vehicle outer side. ### Claim 6 (depends on 1) The pneumatic tire according to claim 1, wherein the loss tangent tan δ at 60° C. of the compound in the region where the rib has the greatest protruding amount is from 0.25 to 0.4, both inclusive, and the loss tangent tan δ in the region of the rib where the protruding amount is the least is from 0.2 to 0.33, both inclusive. ### Claim 7 (depends on 1) The pneumatic tire according to claim 1, wherein a vehicle inner/outer side orientation when mounted to a vehicle is designated, the protruding amounts decreases in order from the vehicle outer side to the vehicle inner side, and the loss tangent tan δ at 60° C. of the compound is smaller on the vehicle inner side than the vehicle outer side. ### Claim 8 (depends on 1) The pneumatic tire according to claim 1, wherein at least four of the at least four ribs protrude to the outer side in the tire radial direction beyond the profile line of the tread surface when viewed in the meridian cross section, the protruding amounts of the at least four ribs decreasing in order from the first side towards the second side in the tire width direction. ### Claim 9 (depends on 1) The pneumatic tire according to claim 1, wherein the cap tread forming the tread surface of the tread portion is composed from at least three different types of compounds. ### Claim 10 (depends on 9) The pneumatic tire according to claim 9, wherein boundaries between the at least three different types of compounds is disposed on ribs that do not correspond to the rib having the least protruding amount or the rib where the protruding amount is the greatest. ### Claim 11 (depends on 10) The pneumatic tire according to claim 10, wherein the at least four ribs protrude to the outer side in the tire radial direction beyond the profile line of the tread surface when viewed in the meridian cross section, the protruding amounts of the at least four ribs decreasing in order from the first side towards the second side in the tire width direction. ### Claim 12 (depends on 1) The pneumatic tire according to claim 1, wherein a boundary between the different types of compounds is disposed on ribs that do not correspond to the rib having the least protruding amount or the rib where the protruding amount is the greatest. ### Claim 13 (depends on 1) The pneumatic tire according to claim 1, wherein the protruding amount from the profile line of each of the at least three of the at least four ribs is from 0.05 mm to 0.09 mm, both inclusive. ### Claim 14 (depends on 1) The pneumatic tire according to claim 1, wherein the protruding amount from the profile line of each of the at least three of the at least four ribs is from 1.6 mm to 2.0 mm, both inclusive.