How Many Wheels? |
Essay by |
||||||||||||||||||||||||||||||||||
October 1999 | |||||||||||||||||||||||||||||||||||
Wheels all around
How many wheels should a car have? You may think the answer to this question is obvious. Four of course, one at each corner. For the same reason that a dog should have four legs: fewer would be awkward, and more would just get in the way. But automobile engineers have been designing cars with three wheels from the very beginning. The oldest existing car in the world is in a museum in France. Cugnot's experimental car is powered by steam and a single front wheel drives and steers the car. The firebox, boiler, and steam engine are all mounted above the front wheel, and the rear of the vehicle is like a big, heavy wagon. That car was built in 1771 and it ran briefly. When the Automobile Age began in the 1890s there appeared several little three-wheelers that looked like crosses between motorcycles and wheelchairs. There always have been three-wheeled motorcycles, usually used for city delivery jobs, but real automobiles with three wheels have never been popular. There have been more than a hundred different makes of cars with three wheels. Some have had their single wheel in front, and some in back. Some have driven the single wheel by a chain, and others have used an ordinary rear axle assembly with a differential. Two small British cars, the Morgan and the Bond, survived for years in the heavily taxed and protected British market. The Morgan three-wheeler had a single rear wheel. It was built from 1910 to 1952; after 1936 Morgan also built cars with four wheels. The little three-wheeler was one of the first cars to have independently sprung front wheels with coil springs. The engine, mounted in front, was a tiny V2 at first, and a wide variety of engines powered the Morgan in later years. The Bond, another very small car with three wheels, had a single front wheel and was built from 1949 through 1974. Bond also built some four-wheeled cars. Two American three-wheelers, the Dymaxion and the Davis, were designed and built with materials and details adopted from aircraft engineering traditions. The Dymaxion and the Davis were promoted as "cars of the future", but neither progressed beyond the prototype stage. Wild claims for speed, economy, and agility were made for both cars. Designed by Buckminster Fuller, three prototypes of the Dymaxion were built in Bridgeport, Connecticut in 1933 and 1934. The single wheel was in the rear. Power was by a Ford V8 engine that could move the light, streamlined car faster than most stock cars. The Dymaxion was built of very light materials and was shaped like the cabin of a dirigible. I saw one in Chicago at the time. With its single rear wheel and the two front wheels placed just forward of the center of gravity the car looked as if it could take off and fly. There was considerable overhang in front. The Davis was built in Van Nuys, California from 1947 to 1949. It had its single wheel in front. The four-cylinder engine was mounted in front and the drive line was conventional, but the chassis and body showed the influence of aircraft designers. Wherever possible the weight was kept low by the use of light materials. Brakes and shock absorbers were somewhat like those used on light aircraft. The single seat was very wide for the 1940s. A removable hardtop was provided. Fewer than twenty of the Davis three-wheelers were built, no two exactly alike. The Davis body was smooth, clean design with very little front or rear overhang. One of the last of the old-style three-wheelers was the little Motorette, built from 1911 to 1913. It was a two-passenger car with a wheelbase of only 74 inches. It had a two-cylinder engine that drove the single rear wheel by a chain. It was built in Hartford, Connecticut. Only a few hundred were sold.
|
|||||||||||||||||||||||||||||||||||
© 1999 Wilfred R. Franson |
|||||||||||||||||||||||||||||||||||
|
|
||||||||||||||||||||||||||||||||||
|