| 摘要 |
The weight, space and convenience advantages of a run-flat tire can be substantial. This is especially true for the urban-economy car or family type vehicles which have limited space available for a spare tire and inadequate space for the removed flat tire. These vehicles also have higher comfort requirements that must be addressed. The mini-spare solution to the flat tire problem has very limited performance capabilities. Other solutions include major modifications in the rim and/or the tire, which are not cost effective or compatible with a conversion to standard tires on the same rims. The run-flat tire of this invention includes thickened sidewall portions, a belt package with a cap ply, lower sidewall rubber support portions, a specially designed bead seat area with a rim seat ply and three carcass layers. The classical problems of inflated vs. deflated performance tradeoffs in ride comfort, handling, radial stiffness and endurance of the tire are substantially improved. This is accomplished with a run-flat tire having relatively small weight increases over a standard tire and a rim that can be used interchangeably with the standard tire. The run-flat tire system of this invention is capable of maximum lateral accelerations under nominal operations of approximately 0.90 gS and extended operating efficiency (i.e., handling and durability) at higher speeds for longer distances. |
