HANOVER, Germany—Continental A.G.'s work on the run-flat problem has spawned two new concepts, one designed to fit standard tires and wheels and the other a radical departure from the standard. The retrofit system, called CSR for ContiSafetyRing, is a light-weight metallic insert that is mounted inside a tire and supports the tire in the event of pressure loss, the company said. Viewed in profile, the insert has a corrugated shape, with the rounded humps providing the support.
Conti claims the system will allow motorists to drive on a flat tire up to 120 miles at 55 mph. It will be available in Europe only, at a cost of about $40 to $45 per tire.
Conti does not require a tire pressure warning system with CSR, saying instead the concept warns the driver through light vibration and increased noise.
The lightweight steel CSR rings weigh seven pounds apiece and can be reused. They are multipiece, to ease mounting inside the tire.
Conti's other idea is the CWS—ContiWheelSystem—which features a complete departure from today's standard fitments in the way the tire is mounted to the wheel.
While CWS resembles the firm's inverted bead ContiTireSystem concept of the mid-1980s, the new system does away with the tire bead and apex construction.
In place of a bead, the tire has only a rubber ``foot'' that is slotted into a C-shaped, circumferential indentation on the wheel, and this is then anchored to the wheel by a rubber ring pressed into the opening.
Conti claims eliminating the bead and apex reduces tire weight enough to yield rolling resistance advantages.
The special wheel also has a built-in support shelf that provides run-flat capability.
The resulting tire/wheel system offers a larger-diameter wheel with the same outside diameter tire measurement, providing vehicle makers the opportunity for larger brakes and new wheel designs.
Conti claims run-flat mobility of at least 120 miles—up to 300 miles under good conditions. CWS will be offered only in combination with a pressure monitor, which the company anticipates developing internally.
Conti said CWS is undergoing testing now by ``leading vehicle makers,'' with an eye toward a market introduction in 2000.