PNEUMATIC TIRE

• US 20180215207A1
• Filed: 07/14/2016
• Published: 08/02/2018
• Est. Priority Date: 09/08/2015
• Status: Active Grant

• Current Assignee: Bridgestone Corporation
• Original Assignee: Bridgestone Corporation
• Inventors: HATANAKA, Shintaro, KUWAYAMA, Isao
• Granted Patent: US 10,639,936 B2
• Time in Patent Office: Days
• CPC Class Codes: B60C 11/032 Patterns comprising isolated recesses
• CPC Class Codes: 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
• CPC Class Codes: B60C 11/1204 with special shape of the sipe
• CPC Class Codes: B60C 11/1236 with special arrangements in the tread pattern
• CPC Class Codes: B60C 2011/0341 Circumferential grooves
• CPC Class Codes: B60C 2011/1254 with closed sipe, i.e. not extending to a groove

Abstract

A pneumatic tire comprises, in a tread surface: at least two circumferential main grooves continuously extending in a tire circumferential direction; and at least one rib-like land portion each defined by two adjacent circumferential main grooves from among the at least two circumferential main grooves. The rib-like land portion has: a circumferential sipe including a circumferential sipe portion extending in the tire circumferential direction; and a both-end closed sipe having both ends terminating within the rib-like land portion. When a land portion width of the rib-like land portion is evenly divided by three where a region at a center in a tire width direction is a center region and regions on both sides of the center region in the tire width direction are side regions, the circumferential sipe portion is located only in the center region, and the both-end closed sipe is located in any of the side regions.

Claims

1. A pneumatic tire comprising, in a tread surface:

at least two circumferential main grooves continuously extending in a tire circumferential direction; and

at least one rib-like land portion each defined by two circumferential main grooves adjacent to each other from among the at least two circumferential main grooves,

wherein the rib-like land portion has;

a circumferential sipe including a circumferential sipe portion extending in the tire circumferential direction; and

a both-end closed sipe having both ends terminating within the rib-like land portion, and

when a land portion width of the rib-like land portion is evenly divided by three where a region at a center in a tire width direction is a center region and regions on both sides of the center region in the tire width direction are side regions, the circumferential sipe portion is located only in the center region, and the both-end closed sipe is located in any of the side regions.

2. The pneumatic tire according to claim 1,

wherein a region enclosed with a circle centering at a centroid of at least one both-end closed sipe and having a radius of 0.15 W has no groove or sipe other than the both-end closed sipe in a tread surface developed view, where W is the land portion width of the rib-like land portion.

3. The pneumatic tire according to claim 1,

wherein a region enclosed with a circle centering at a centroid of at least one both-end closed sipe and having a radius of 0.50 W has, in addition to the both-end closed sipe, any of a groove and a sipe other than the both-end closed sipe in a tread surface developed view, where W is the land portion width of the rib-like land portion.

4. The pneumatic tire according to claim 2,

wherein a region enclosed with a circle centering at a centroid of at least one both-end closed sipe and having a radius of 0.50 W has, in addition to the both-end closed sipe, any of a groove and a sipe other than the both-end closed sipe in a tread surface developed view, where W is the land portion width of the rib-like land portion.