At the 2012 Tokyo Motor Show, Bridgestone displayed its Airless Concept Tire to a fascinated crowd. With it’s bright green exterior, Bridgestone Tires is making an environmental statement while implementing a successful design touch as well. It was nothing short of eye catching when it was rolled out on the show floor mounted on an electric scooter.
Bridgestone engineers hope to completely eliminate flats with these tires. Airless tires will never create a blow-out simply because there is nothing to blow out. There are no sidewalls. Instead the airless tires are made with thermoplastic spokes that curve out from their aluminum hub in intricate and complicated patterns that keep the shape of the tire.
The spokes are elastic enough to provide sufficient spring and flexibility for a comfortable ride, but rigid enough to support the weight of the vehicle and prevent vibration. The outer ends of the thermoplastic spokes hold a wide band of tire tread in place, which finishes the airless tire and gives it a traditional rubber compound footprint where the tire contacts the road.
Bridgestone is not the only tire manufacturer with an airless tire program. Michelin has introduced an airless tire, named the Tweel. Yokohama has an airless tire project. Goodyear created an airless tire for NASA, which was used on the Moon Rover. Several smaller companies are developing modern airless tires for military use.
Airless tires are also better for the environment, Bridgestone says the new concept tire reduces rolling resistance, using less gasoline. Recycling airless tires is easier as thermoplastic can be melted and then remolded into new products. As airless tires continue to replace pneumatic tires, tires piling up in dumps and landfills will continue to be reduced. There are now and estimated 300 million waste tires dumped in the US annually. The cost to recycle these tires is prohibitive, which translates into a very small percentage of recycled pneumatic tires.
Airless tires will probably show up first for low speed applications in controlled environments. Think small carts, wheeled bins or machinery such as forklifts. They will also be seen on military vehicles, where avoiding flat tires can be a matter of life and death.
There is still much work to be done. Engineers need to make sure that the spokes maintain their flexibility, and keep out rocks, dirt, mud, and even snow from within the spokes. The tires must perform well and maintain their properties in hot weather, cold weather, and wet conditions.
As the technology evolves, we will keep you informed.