Patent ID: 8561661

Claim:
A run-flat pneumatic tire assembly comprising: a pneumatic tire including an elastomeric casing disposed circumferentially about an axis, said elastomeric casing including a crown portion and a pair of axially-spaced sidewalls extending radially inwardly from along said crown portion, said crown portion including an outer surface and an inner surface that at least partially defines a tire cavity; and, a structural insert including a longitudinally-extending and approximately planar length of strip material having first and second longitudinally-extending sides defining a strip material thickness, opposing longitudinally-extending edges defining a strip material width, and a first stress level along said first side; said length of strip material disposed within said tire cavity in a helical arrangement with said first side is facing outwardly toward said inner surface of said crown portion to at least partially form said structural insert, said structural insert being pre-stressed due to at least a reactive force applied to said helical arrangement of said length of strip material within said tire cavity by said tire, said reactive force maintaining said length of strip material in said helical arrangement resulting in a second stress level along said first side that is greater than said first stress level and such that a theoretical neutral plane is established along said length of strip material between said first and second sides thereof with said first side of said length of strip material being in tension and said second side of said length of strip material being in compression.