Submitted by Satoshi Shinden
Japanese wheel makers are finding developing airless puncture-free tires a bit of a bumpy ride. The tires would help prevent accidents from blowouts and would also reduce the weight of cars because no spare would be required. But comfort is the issue. It’s not much fun negotiating a pothole-filled road without air in the tires to soften the blows from the bumps, especially if one has just consumed a substantial meal. Even if the air-free tires are not preferred by drivers, they could be used in self-driving vehicles.
A small vehicle running on new airless tires called “noair” was unveiled by Toyo Tire & Rubber Co. at the Expo ’70 Commemorative Park in Suita, Osaka Prefecture, in a demonstration on Sept. 8. The wheels appeared to work normally when taking curves or braking suddenly, but the
vehicle shook violently at times and the wheels made a noise. The tires are filled with 100 thin resin rods instead of air to support the weight of vehicles and absorb shocks. Toyo Tire & Rubber began developing the puncture-free tires in 2006, and their rotation and braking performance are now almost comparable to that of normal tires.
“The new tires have the potential of replacing long-established air-filled wheels,” said Satoru Moriya, head of the No. 1 technical department of Toyo Tire & Rubber, referring to the future commercialization of the tires. “We are now opening the door to that future.”
The lower weight from not carrying a spare tire will also result in higher fuel efficiency. Electric cars will also have more space to install batteries, enabling them to go longer distances. The safety of self-operating cars can also be improved with airless tires because automatic driving systems do not need to take countermeasures against punctures. Bridgestone Corp. and Sumitomo Rubber Industries Ltd. are also developing airless tires. But many hurdles remain to make them commercially available for passenger automobiles.
Shock absorption does not match that of air-filled wheels. They are also not strong enough to run at high speeds, and the auto industry would have to draw up new standards. Airless tires have already been used for vehicles other than passenger automobiles. While Bridgestone is going to market air-free tires for bicycles, France’s Michelin sells airless tires for construction and agricultural machines in the United States. Sumitomo Rubber is testing its puncture-free tires on golf carts.
Toyo Tire & Rubber is looking to spread the use of its airless tires first for one- or two-seater super-compact cars and compact vehicles, as those types of car rarely run at high speeds. ❂
