Bridgestone re-inventing the wheel with air-free tyre
The days of worrying about punctures and of remembering to check tyre pressure may soon be a distant memory! Bridgestone has revealed its second generation ‘air free concept’ tyre for the first time. Its latest improvements to the concept bring Bridgestone one step closer to a viable,commercially available air free tyre. It features improved load-bearing capabilities, environmentaldesign and driving performance.
Looks different
The revolutionary non-pneumatic design of the air-free tyre represents a striking change of image. A unique structure of spokes – made of thermoplastic resin *1 – stretches along the inner sides ofthe tyres and support the weight of the vehicle.
Higher levels of environmental friendliness
Along with the rubber in the tread portion, the materials used in the tires are recyclable, contributing to the efficient use of resources. Further, by pursuing extremely low rolling resistanceand contributing to reductions in CO2 emissions through use of proprietary technologies,Bridgestone believes it is possible to achieve even higher levels of environmental friendliness andsafety.
Bridgestone is pursuing this technological development with the aim of achieving a “cradle tocradle” process that proactively maximizes the cyclical use of resources from worn tires into newtires and the use of recyclable resources.
New technologies
New technologies used in and special features of the second generation tires are as follows:
1. Increased Versatility Through Improved Load-Bearing Capabilities and Driving Performance
Bridgestone is further optimizing the spoke structure by using high-strength but flexible high-performance resin as a material and employing finite element method (FEM) simulations in the design to reduce stress and deformation in the inner part of the tire. By doing so, the secondgeneration of “Air Free Concept tire” has increased versatility through improved load-bearing capabilities and driving performance compared with the first generation *2. High-speed travel(maximum 60 km/h) in ultralight vehicles*3 has also become possible.
2. Pursuing Low Rolling Resistance to Reduce CO2 Emissions
About 90% of energy loss from tire rolling resistance comes from repeated changes in the shape oftyres as they roll. In the second generation of airless tires, Bridgestone has succeeded in making asignificant reduction in energy loss by using proprietary materials technologies and simplifying thestructure of the tires. As a result, these “Air Free Concept tire” have achieved the same level of lowrolling resistance as our pneumatic fuel-efficient tires, making possible a contribution to reductionsin CO2 emissions.
Here are some notes and explaations to help you understand this new concept:
*1 A synthetic resin that becomes flexible when heated, can be processed into a variety of shapes, and becomes hard when cooled. The changes from heating and cooling can generally be repeated, making it easy to both mold and recycle the material.
*2 Conditions for the first generation airless concept tire test vehicle: Vehicle weight of 100kg andmaximum speed of 6 km/h
Conditions for the second generation airless concept tire test vehicle: Vehicle weight of 410kg andmaximum speed of 60 km/h
*3 Vehicles for one or two people which are more compact than automobiles, have a small turning circle, are highly environmentally friendly, and allow easy local movement.
The airless concept tire is one of Bridgestone’s initiatives aimed toward 100% use of sustainablematerials and contributing to globally agreed CO2 emissions reduction targets (reduction of at least 50%) as part of the Company’s long-term vision.