Toyo unveils 'noair' non-pneumatic concept

HYOGO, Japan — Toyo Tire & Rubber Co. Ltd. has unveiled a version of a non-pneumatic tire, dubbed "noair," that it indicated could be a prelude to a commercially viable product.

Toyo said the noair concept, which is based on an airless prototype it unveiled in 2012, uses "high-rigidity resin" spokes to support the load.

The Japanese tire company also said it is considering shifting its efforts on this front from the laboratory-level to a market perspective, reflecting "substantial improvements" it has made in the product's technology as well as growing market acceptance for such products.

Toyo said key improvements over earlier prototypes are in the areas of rolling resistance and noise reduction.

The tire's basic structure features an X-shaped spoke configuration, Toyo said, which differs from the earlier prototypes' elliptical spoke configuration.

The new design alternately crosses the width of the noair tire from the outside to the inside and vice-versa, creating a support configuration that Toyo claims improves durability.

Toyo did not disclose details about what type of resin it is using in the spokes but said the outer tread uses its proprietary "nano balance" technology rubber compound geared toward reduced rolling resistance.

The wheel's outer diameter ring — the connection between the wheel and tread — is reinforced with carbon fiber-reinforced plastic, which serves to reduce the load imposed on the spokes.

In addition, the number of spokes has been doubled (100 pitch) vs. the previous model, distributing contact pressure, reducing the impact sounds from the spokes that are generated when they come into contact with the ground for a quieter ride.

Toyo claims the latest version "vastly exceeds" the equivalent legal and regulatory durability requirements for pneumatic tires and is at least eight times better than previous prototypes.

Rolling resistance has been reduced by at least half compared to previous prototypes and is 25 percent lower than commercially available comparable Toyo pneumatic products.

Road noise has been reduced to a level similar to that of current pneumatic tires, Toyo said.

In terms of the concept's commercial prospects, Toyo expects demand for maintenance-free tires to increase, especially as electric vehicles and compact cars gain more acceptance and safety, in the form of flat-free performance, takes on more importance.

Toyo acknowledges there "outstanding issues to be resolved" before non-pneumatics gain favor in every-day use but said it will continue to develop the concept by leveraging knowledge gained through research across multiple fields.