Text 1 The history of the automobile




The history of the automobile goes back several hundred years. One of the earliest attempts to propel a vehicle by mechanical power was suggested by Sir Isaac Newton about 1680. It was little more than a toy consisting of a steam boiler supplying a steam jet turned to the rear.

However, the credit for building the first self-propelled road vehicle must undoubtedly go to the French military engineer, Nicolas Cugnot. Between 1763 and 1769 two steam-driven carriages were built and tried.

In 1784 the Russian inventor Kulibin built a three-wheeled carriage. In his vehicle he used for the first time such new elements as brakes, rollers and a gear-box. The first Englishman to build a full-self-propelled vehicle for use on the roads and to obtain practical results was Trevithick. Between 1798-1800 he built several working models.

Up to 1960 most all road vehicles were powered by steam engines which ran at slow speeds. In 1860 Lenoir of Paris built an internal combustion engine which ran on city gas, the gas being ignited by an electric spark. In 1866, Otto invented the type of four-stroke cycle engine which is used today.

Slowly but surely the auto industry is perfecting a number of alternatives to the conventional engines found in almost all of today's passenger cars.

Two prime factors lie behind the search for different engines - the necessity to reduce air pollution by requiring cleaner auto exhaust and the desire to produce cars that will ran farther on a gallon of fuel.

While basic research is continuing on electric and steam-powered engines, it is the diesel, turbine and Stirling that are current industry favourites.

Diesels get better mileage than gasoline engines, and the fuel is usually cheaper.

In 1890's Rudolf Diesel, a German, invented the engine that bears his name. As air is drawn into the engine and compressed internal temperatures rise, and pressures reach two to three times those in a gasoline engine. The extreme pressures have meant that diesels usually are much larger and heavier that gasoline engines of the same power potential.

The disadvantages of diesels as passenger-car engines are slow performance, noise and smoke.

All the companies investigating diesels are trying to reduce noise and smoke, but the problems are not yet entirely solved. Even the 28,000-dollar Mercedes clatters when started on a cold morning. And the warm up period for all diesels seems too long to drivers accustomed to gasoline models.

The turbine and Stirling are multifuel engines, capable of running on any liquid that will burn, including such exotic types as peanut oil and perfume. This would be a major advantage if severe petroleum shortages develop.

The turbine cars now operating are hand-built models that cost more than 1 million dollars each. Alloys of precious metals of high durability are still required for certain vital turbine parts. Engineers believe that progress in ceramics holds the key to making turbines practical alternatives to present-day engines.

Experts say that the Stirling is the most promising among the three favoured engines.

The Stirling concept, first offered more than 150 years ago by a Scottish clergyman, involves external instead of internal combustion.

In 1816 Robert Stirling patented a new engine for pumping water out of mines and quarries. It could run on almost any fuel, he boasted - including whisky. Indeed the parson had such faith in his engine that he often cut his Sunday sermons short to work on it. However, when Stirling died in 1878 at the age of 88, his engine was still unperfected. Soon it was totally overshadowed by the newer gasoline-powered internal combustion engine.

Unlike typical internal combustion engines, the Stirling engine is powered by heat from an external source. In the new design, hydrogen gas is heated by a burner, which can run on virtually all kinds of fuel. Hydrogen then expands, enters one cylinder and pushes a sliding piston. As piston moves, it forces gas out of the other end of the cylinder; the emerging gas is cooled and then moves towards an adjacent cylinder where heat is applied once more and the process is repeated.

Engineers point out that a Stirling engine would be quieter that an equivalent internal combustion engine, would emit less toxic gases, and would use fuel more economically. Having no need for valves or cars, it would also have fewer parts. Stirling's old dream might yet become reality - perhaps by the end of the twentieth century.

Now, since experts seek fuel-saving, less-polluting alternatives to the modern auto engine, Stirling's machine has started a new life, they show great interest in the work of a giant Dutch electronics firm, which has tested Stirling prototypes in boats, large pumps (to help dry out Holland during 1952's floods) and even buses. In 1972, Ford signed an agreement with the firm for joint development of a Stirling engine for passenger cars.

As for electric cars, several types of small battery-powered vehicles are in production, but it is most unlikely that they will replace more conventional vehicles.

 

Text 2 Automobile

Our era has sometimes even been named the, age of electricity and auto­mobiles. What is the reason for the tremendous advancement of automobiles? The motor car is the most efficient thermal powered road vehicle, since it makes the most effective use of the most widely spread and comparatively cheap fuel: gasoline and other oil products. Another reason for the vast expansion of automobile transports its comparatively high speed and its versatility. Bad roads are only a partial impediment to the automobile, espe­cially the modern lorry, which scales steep gradients, seldom sticks in mud, and easily negotiates the sharpest curves/ Automobiles to a vast vari­ety of purposes and they possess most different design. Besides passenger cars and lorries, there exist special service motor cars, such as ambulances, emergency technical repair, machines for fire-brigades, dump-cars, tanks for liquids of various description beginning with milk tanks and ending with oil tanks. Motor buses - both city and interurban are winning every day in comfort, speed and safety. Tourism is materially helped by motor-buses which, along with mo­tor-launches, are responsible for the transportation of tourists to various places of interest. Not to be forgotten in connection with internal-combustion engine vehicles is also the motor-cycle which caters for individual needs and, to a great extent, for sport.

As to freight - carrying trucks, we see here a vast range of most different types. Nowadays the traditional road-going lorry has been joined by long distance heavies, containers trailers, haul trucks, and on the other end of the scale there are machines designed for short-run operation at construction sites, forest estates, etc. ranging from the tropics to Polar Regions.

Automobiles are trackless, self-propelled vehicles for land transportation of people or goods, or for moving materials. So there are three main types of automobiles. These are passenger cars, buses, and lorries. The automobile con­sists of the following components:

a) the engine

b) the framework

c the mechanism that transmits the power from the engine to the wheels

d) the body

Passenger cars are, as a rule, propelled by an internal combustion engine. They are distinguished by the horsepower of the engine, the number of the cyl­inders in the engine and the type of the body, the type of the transmission, wheelbase, weight and overall length.

There are engines of various designs. They differ in the number of cylin­ders, their position, their operation cycle, valve mechanism, ignition and cool­ing system.

 



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