AIR MAINTENANCE TIRE

• US 20170217262A1
• Filed: 01/26/2017
• Published: 08/03/2017
• Est. Priority Date: 01/29/2016
• Status: Active Grant

• Current Assignee: Goodyear Tire & Rubber Company
• Original Assignee: Goodyear Tire & Rubber Company
• Inventors: KANG, Jungmee, VOJTKO, Daniel, CHANDRA, Dinesh, BUEHLER, Betul, GARN, Benjamin Isaiah, LEE, Byoung Jo
• Granted Patent: US 10,449,813 B2
• Time in Patent Office: Days
• CPC Class Codes: B60C 1/00 Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition
• CPC Class Codes: B60C 13/02 Arrangement of grooves or ribs
• CPC Class Codes: B60C 23/123 Elongate peristaltic pumps
• CPC Class Codes: C08L 7/00 Compositions of natural rubber
• CPC Class Codes: C08L 9/00 Compositions of homopolymers or copolymers of conjugated diene hydrocarbons

Abstract

A self-inflating tire assembly includes an air tube mounted within a tire sidewall or chafer groove. The air tube is in contacting engagement with opposite angled groove surfaces surrounding the air tube. A segment of the air tube is flattened from an expanded diameter to a flat diameter by bending and compression of the groove in a rolling tire footprint to force air evacuated from the flattened segment along a tube air passageway. A coverstrip overlays and seals the groove and provides an abrasion resistant surface on the exterior of the tire. The coverstrip is made from a vulcanizable rubber composition comprising from 50 to 80 phr of a polybutadiene, from 50 to 20 phr of natural rubber, and from 0.1 to 5 phr of a vulcanization modifier.

Claims

1. A self-inflating tire comprising:

a tire having at least one of a sidewall and a chafer;

a groove positioned within the sidewall or chafer;

an air tube positioned within the groove in contacting engagement with opposite groove surfaces at least partially surrounding the air tube;

a coverstrip overlaying and sealing the groove, the coverstrip comprising a vulcanizable rubber composition comprising

from 50 to 80 phr of a polybutadiene having a microstructure comprised of about 96 to about 99 percent cis 1,4-isomeric units, about 0.1 to about 1 percent trans 1,4-isomeric units and from about 1 to about 3 percent vinyl 1,2-isomeric units;

a number average molecular weight (Mn) in a range of from about 75,000 to about 150,000 (relatively low Mn for a cis 1,4-polybutadiene elastomer) and a heterogeneity index (Mw/Mn) in a range of from about 3/1 to about 5/1 (a relatively high heterogeneity index range illustrating a significant disparity between its weight average and number average molecular weights);

from 20 to 50 phr of natural rubber; and

from 0.1 to 5 parts by weight, per 100 parts by weight of rubber (phr), of a vulcanization modifier selected from the group consisting of nitroso compounds, phthalimides, anhydrides and acids.

2. The self-inflating tire of claim 1, further comprising:

an adhesive strip disposed between the coverstrip and the tube, the adhesive strip comprising a vulcanizable rubber composition comprising

from 50 to 80 phr of a second polybutadiene having a heterogeneity index (Mw/Mn) in a range of from about 1.5/1 to 2.5/1;

from 20 to 50 phr of natural rubber; and

from 0.1 to 0.2 phr of the vulcanization modifier.