Insert for a pneumatic tire

1. An insert for a pneumatic tire assembly comprising:

a tire mounted on a rim, the tire having opposed sidewalls interconnected by a tread portion and the tire defining an interior volume with a width W PT and an interior surface;

an annular member having a base portion, an outer portion and opposed side portions, wherein the annular member is inserted into the interior volume of the tire so that there is an empty space between the outer portion of the annular member and the interior surface of the tire at the tread portion and there is an area of contact between the opposed side portions of the annular member and the respective opposed sidewalls of the tire;

wherein the annular member has a width W AM that is greater than W PT as measured prior to insertion of the annular member into the interior volume of the tire, and the annular member exerts an outward pressure against the tire over the area of contact between the opposed side portions of the annular member and the respective opposed sidewalls of the tire.

2. The insert according to claim 1 in which the contact area is less than 80 percent of the interior surface of the tire after insertion of the annular member into the interior volume of the tire.

3. The insert according to claim 2 in which W AM is greater than W PT over the entire contact area prior to insertion of the annular member into the interior volume of the tire.

4. The insert according to claim 3 in which annular member comprises a compressible material and the annular member is compressed after insertion into the interior volume of the tire so that the opposed side portions exert outwardly directed pressure against the opposed sidewalls of the tire and such that the insert stabilizes the tire sidewalls.

5. The insert according to claim 4 wherein, in an assembled, unloaded state, the outwardly directed pressure is at least 0.1 PSI.

6. The insert according to claim 5 in which the annular member defines a concave surface in the direction of the base portion of the annular member.

7. The insert according to claim 1 wherein W AM is at least 1.01 W PT prior to insertion of the annular member into the interior volume of the tire.

8. The insert according to claim 1 wherein the rim and the base portion have lateral profiles and wherein the lateral profile of the base portion conforms to the lateral profile of the rim.

9. The insert according to claim 2 in which the upon insertion of the annular member into the interior volume of the tire the annular member applies an outward lateral force against the interior surface of the tire of at least 0.1 psi over the entire contact area to thereby laterally stabilize the tire.

10. The insert according to claim 2 in which W AM prior to insertion of the annular member into the interior volume of the tire is at least 1 mm greater than W PT .

11. The insert according to claim 1 in which the width of the annular insert at all locations in the contact area is at least 1 mm greater than the width between the interior sidewalls of the tire at all locations in the contact area.

12. An insert for a pneumatic tire having an interior surface, a tread portion and opposed sidewalls with a width therebetween, comprising:

an annular member having a base portion, an outer portion and opposed sidewalls, the annular member adapted to be assembled with the tire so that the annular member contacts less than 80 percent of the interior surface of the tire and provide an outward pressure against the opposed sidewalls, and

wherein at all locations where the annular member contacts the interior surface of the tire when the annular member has been assembled with the tire, the annular member has a width that is greater than the width between the opposed sidewalls when measured prior to assembly of the annular member with the tire; and

wherein the annular member laterally stabilizes the tire sidewalls.

13. The insert according to claim 12 , further comprising an inflatable bladder disposed radially outside of the annular member.

14. The insert according to claim 12 in which prior to assembly with the tire the annular member has a width W AM that is at least 1 mm greater than a width W PT between the opposed sidewalls.

15. A tire assembly comprising:

a pneumatic tire having opposed sidewalls with a width therebetween and interconnected by a tread portion and an interior surface interiorly of the sidewalls and the tread portion;

an annular foam member having opposed sidewalls contacting less than 80 percent of the interior surface the thereby define an area of contact between the foam member and the interior surface when the annular foam member is assembled with the tire, and wherein a width of the foam member over the entire area of contact prior to assembly with the tire is greater than the width between the opposed sidewalls over the entire area of contact so that the foam member exerts an outwardly directed pressure against the opposed sidewalls of at least 0.1 psi.

16. The tire assembly according to claim 15 wherein the foam member exerts an outwardly directed pressure against the opposed sidewalls of at least 0.1 psi over the entire area of contact to thereby laterally stabilize the sidewalls.

17. The tire assembly according to claim 15 adapted to be mounted to a rim and wherein the foam member has a base portion that conforms to the rim.