Consider the lowly pneumatic tire.
It's out there in freezing cold and burning heat. It travels in rain, snow, mud, gravel sand and asphalt. And its performance absolutely characterizes a car - after all, it is the tire that puts the car in contact with the road.
The word "tire" didn't originally mean the inflated, vulcanized rubber structure on cars today. The earliest tires included wood, metal and leather. But innovations, first from independent inventors, then by suppliers, changed all that over time.
Word of a new material that would eventually form the mainstay for tire manufacturing emerged in 1843. That is when Charles Goodyear in the United States and Thomas Hancock in Scotland each received patents for the sulfur-based vulcanization of rubber. Before that, rubber was considered a novelty material.
In 1845, Scottish inventor Robert Thomson created a leather tire that was supported by compressed air held by a canvas inner tube.
Thomson called it the "aerial wheel," and his thought was to make carriage rides smoother. But problems making and fitting the fragile pneumatic tires killed the innovation.
In 1887, Scotsman John Boyd Dunlop invented a pneumatic tire for bicycles. He conceived of a rubber outer tire and a leather inner tube to hold compressed air, and received a patent for his invention in 1889, which was rescinded the next year when the earlier Thomson patent was rediscovered. Dunlop's invention, though, went into high-volume manufacturing.
The earliest pneumatic tires were basically unique parts custom-assembled on a wheel. It took Edouard and Andre Michelin, in France in 1904, to invent the "demountable" pneumatic tire on a rim that could be quickly removed and reinstalled from a standard wheel. Pneumatic tires were then adopted for the new horseless carriage invention.
In 1907, Goodyear found commercially practical ways to reinforce tires using cotton cord fibers.
In the groove
Tires with grooved tread came along in 1908 when Frank Sieberling decided he could improve road traction by inventing a groove-cutting machine for production tires at Goodyear Tire & Rubber Co. Meanwhile, Harvey Firestone took the opposite approach of molding a raised tread in the form of letters spelling "non-skid" onto its tires.
In 1910, researchers at B.F. Goodrich Co. found they could extend the life of tires by adding carbon black to the rubber mix as a reinforcing agent.
With a bias-ply structure - cording that was looped across the tire in a long spiral, with layers of cords crossing over one another - a tire could last about 13,000 miles.
The 1923 innovation by Firestone of "balloon" tires used thin sidewalls, pressures of less than 40 psi and a small bead to hold the tire to the wheel. The tires swept the market by 1934 because they gave a bigger tread contact patch for the car to work with. By the 1960s, tire engineers seemed to have hit the wall for tire lifespan. Bias ply tires rarely went beyond 17,000 miles.
According to an Automotive News special section in 1996, the domestic tire industry was shaken in 1965 when Sears, Roebuck & Co. signed a sales contract with Michelin to sell radial replacement tires. Four years later, Michelin radial tires were original equipment on the Lincoln Mark III.
Michelin researchers created a radial tire in the 1940s. The radial used cords that didn't criss-cross, and counted on a limber sidewall and the strength of a set of steel belting to keep the tire tread flat on the road.
The tires proved themselves capable of unprecedented lifespans of more than 20,000 miles and saved fuel. At the same time, they gave remarkable control to the driver. By the 1970s, radials had driven bias-ply tires out of the market.
Since then tire innovations have included extended tread life, styling and performance changes and added safety.
For example, run-flat tires developed by Michelin in the 1990s are available on a few high-end production vehicles. More common are electronic tire pressure monitoring systems that warn drivers of dangerous temperature and inflation conditions.