Tire with integral foamed noise damper

Abstract

The present invention is directed to a pneumatic tire having two spaced inextensible beads; a ground contacting tread portion; a pair of individual sidewalls extending radially inward from the axial outer edges of said tread portion to join the respective beads, the axial outer edges of the tread portion defining a tread width; a supporting carcass for the tread portion and sidewalls; and at least one foamed structure disposed radially inwardly of the carcass and exposed to the inner cavity of the tire, the foamed structure including a co-vulcanized foamed rubber composition having a density ranging from 0.1 to 1 g/cm3.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more readily understood with respect to the accompanying drawings wherein:

FIG. 1 is a cross-sectional view of one embodiment of a tire having a foamed structure according to the present invention;

FIG. 2 is a cross-sectional view of another embodiment of a tire having a foamed structure according to the present invention;

FIG. 3 is a cross-sectional view of another embodiment of a tire having a foamed structure according to the present invention;

FIG. 4 is a perspective view of another embodiment of a tire having multiple foamed structures according to the present invention;

FIG. 5 is an enlarged view of a photograph showing a plurality of foamed projections in a tire having a foamed structure;

FIG. 6 is a graph showing the noise level generated during testing of a tire according to the invention.

Claims

1. A pneumatic tire comprising two spaced inextensible beads; a ground contacting tread portion; a pair of individual sidewalls extending radially inward from the axial outer edges of said tread portion to join the respective beads, the axial outer edges of the tread portion defining a tread width; a supporting carcass for the tread portion and sidewalls; and at least one foamed structure disposed radially inwardly of the carcass and exposed to the inner cavity of the tire, the foamed structure comprising a co-vulcanized foamed rubber composition having a density ranging from 0.1 to 1 g/cm3.

2. The pneumatic tire of claim 1, wherein the at least one foamed structure has a density ranging from 0.2 to 0.9 g/cm3.

3. The pneumatic tire of claim 1, wherein the at least one foamed structure has a density ranging from 0.2 to 0.8 g/cm3.

4. The pneumatic tire of claim 1, wherein the at least one foamed structure further comprises an integral foamed structure extending circumferentially and radially inward from the carcass, and axially from bead to bead.

5. The pneumatic tire of claim 1, wherein the at least one foamed structure further comprises an integral foamed structure extending circumferentially and radially inward from the carcass, and axially no more than 50 percent of the tread width.

6. The pneumatic tire of claim 1, wherein the at least one foamed structure extends axially in a range of from about 10 percent to 50 percent of the tread width.

7. The pneumatic tire of claim 1, wherein the at least one foamed structure is substantially centered axially on the axial centerline of the tire.

8. The pneumatic tire of claim 1, wherein the at least one foamed structure further comprises a plurality of foamed projections extending radially inward from the carcass.

9. The pneumatic tire of claim 1, wherein the at least one foamed structure further comprises a plurality of foamed projections extending radially inward from the carcass, the foamed projections selected from foamed rectangles, foamed cubes, foamed pyramids, foamed hemispheres, foamed cylinders, foamed cross hatching, foamed lettering, and foamed logos.

10. The pneumatic tire of claim 1, wherein the at least one foamed structure further comprises a plurality of foamed projections extending radially inward from the carcass, the foamed projections comprising at least part of a foamed inverse of an impressed tire bladder surface pattern.

11. The pneumatic tire of claim 1, wherein the at least one foamed structure comprises a plurality of foamed projections extending radially inward from the carcass, the foamed projections together comprising a series of foamed ridges.

12. The pneumatic tire of claim 1, wherein the at least one foamed structure extends axially in a range of from about 20 percent to about 40 percent of the tread width.

13. The pneumatic tire of claim 1, further comprising a co-vulcanized innerliner layer disposed between the carcass and the at least one foamed structure.

14. The pneumatic tire of claim 1, wherein the at least one foamed structure has a porosity ranging from about 20 to about 80 percent by volume.

15. The pneumatic tire of claim 1, wherein the at least one foamed structure has a porosity ranging from about 30 to about 70 percent by volume.