What Is a Pneumatic Tire?

Most of the tires you will come across in the modern world would be considered to be pneumatic. The history of pneumatic tires starts shortly after the start of using rubber to provide a more cushioned ride for wheeled vehicles. The modern transportation system would not function without modern pneumatic tires.

Definition

  • A dictionary definition of a pneumatic tire is "a tire made of reinforced rubber and filled with compressed air; used on motor vehicles and bicycles, etc." That definition fits almost every tire on cars, trucks, bikes, motorcycles, buses and airplanes.

    Large pneumatic tire, NASA/courtesy of nasaimages.org

History

  • The first tires were iron bands around wooden wheels. Tires made of solid rubber came into use in the mid-19th century. Irishman John Dunlop is credited with inventing and patenting the first successful pneumatic tire with his inner-tubed bicycle tire. Dunlop's 1888 patent used the term "pneumatic" for the first time.

    The Michelin brothers, André and Édouard, were the first to use pneumatic tires on a car in 1895. Their company eventually became a leading producer of tires. Goodyear Tire company was started in 1898. Firestone Tire & Rubber company was the second United States tire company in 1900.

Function

  • For the first half of the 20th century, pneumatic tires were made of reinforced layers of cord or plys covered with rubber with a tread pattern for traction. The plys were laid an an angle or bias to provide strength to the tire and define its shape. These "bias ply" tires required a rubber inner tube to hold the air pressure.

    Radial tires, with the plys running at 90 degrees across the tire body were invented by Michelin in 1948 but did not go into widespread use in the U.S. until the late 1970s. Radial tire provide longer life and greater fuel economy. They are also of "tubeless" design where the tire forms an airtight seal with the wheel and no inner tube is required.

Significance

  • Pneumatic tires are now in such widespread use the term "pneumatic" is rarely used when discussing air-filled tires. Since the invention of the pneumatic tire the transportation system in the U.S. has gone from one dependent on railroads for the transport of people and products to a system of interstate highways used by cars and truck to move around the country.

    Non-pneumatic tire, courtesy of Resiliant Technologies

Potential

  • Pneumatic tires have been in use for more than 100 years. Now companies are looking for alternatives to air-filled tires. Resilient Technologies Co. of Wausau, Wisconsin is working on non-pneumatic tire technology for the U.S. military. The Army is looking for new tire technology that will survive the rigors of combat.