Goodyear Unveils Self-Inflating Tire System

One day cars and trucks could be equipped with tires that sense when they need air and pump themselves up automatically, says Goodyear Tire & Rubber Co.

This week at the IAA commercial vehicle show in Hannover, Germany, the company unveiled a system that does just that.

Still in the concept stage, the technology features a small, flexible inflation tube ring mounted inside the outer bead of the tire. The tube is fitted with an intake valve that opens to the outer surface of the tire and an outlet valve on the opposite side of the ring that opens into the tire cavity.

When a sensor determines the tire's air pressure is too low, it opens the intake valve. Air is drawn into the tube and compressed by the natural tire deformation that occurs as the tire rolls along the road surface. The outlet valve then dumps the compressed air into the tire. The system closes the intake valve when the proper air pressure is re-established.

Such a system could improve fuel economy and extend the life of truck tires, which are typically pressurized to 105 psi about three times that of a car tire, according to Goodyear. It figures maintaining correct air pressure could save a fleet operator $627 per year in fuel and extend tread life as much as 16%.

Goodyear envisions the system being built into a commercial tire when it is retreaded. The company has confirmed that the system works and says it plans an extensive fleet test next year.

System development was supported in part by a $1.5 million grant from the U.S. Dept. of Energy's Office of Vehicle Technology. Goodyear also received a grant from the Luxembourg government to develop a version of the technology for consumer tires.