Referatas
Means of transport
“Car”
2005
Walking used to be to most common way to move from one place to an other.
However, postcards often also show the major means of transportations. Some of them completely disappeared little by little, like the dogs carts, some others evolved like the bus :
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An automobile is a wheeled vehicle that carries its own motor.
Different types of automobiles include cars, buses, trucks, jeeps, and vans, with cars being the most popular. The term is derived from Greek
‘autos’ (self) and Latin ‘movére’ (move), referring to the fact that it
‘moves by itself’. Earlier terms for automobile include ‘horseless carriage’ and ‘motor car’. An automobile has seats for the driver and, almost without exception, one or more passengers. It is the main source of transportation across the world.
As of 2005 there are 500 million cars worldwide (0.074 per capita), of which 220 million are located in the United States (0.75 per capita).
The modern automobile
The modern automobile powered by the Otto gasoline engine was invented in
Germany by Carl Benz. Even though Carl Benz is credited with the invention of the modern automobile several other German engineers work on building the first automobile at the same time. The inventors are: Carl Benz on July
3, 1886 in Mannheim, Gottlieb Daimler and Wilhelm Maybach in Stuttgart (also inventors of the first motor bike) and in 1888/89 German-Austrian inventor Siegfried Marcus in Vienna.
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Let’s check out more:
Nicolaus August Otto
Nicolaus August Otto invented the gas motor engine in 1876.
Gottlieb Daimler
In 1885, Gottlieb Daimler invented a gas engine that allowed for a revolution in car design.
Karl Benz (Carl Benz)
Karl Benz was the German mechanical engineer who designed and in 1885 built the world’s first practical automobile to be powered by an internal-
combustion engine.
John Lambert
America’s first gasoline-powered automobile was the 1891 Lambert car invented by John W. Lambert.
Duryea Brothers
They founded America’s first company to manufacture and sell gasoline-
powered vehicles.
Henry Ford
Henry Ford improved the assembly line for automobile manufacturing (Model-
T), invented a transmission mechanism, and popularized the gas-powered automobile.
Rudolf Diesel
Rudolf Diesel invented the diesel-fueled internal combustion engine.
Charles Franklin Kettering
Charles Franklin Kettering invented the first automobile electrical ignition system and the first practical engine-driven generator.
Steam powered vehicles
Steam-powered self-propelled cars were devised in the late 18th century.
The first self-propelled car was built by Nicolas-Joseph Cugnot in 1769—it could attain speeds of up to 6 km/h. In 1771 he designed another steam-
driven car, which ran so fast that it rammed into a wall, producing the world’s first car accident.
Combustion engine
In 1807 François Isaac de Rivaz designed the first internal combustion engine (sometimes abbreviated „ICE” today). He subsequently used it to develop the world’s first vehicle to run on such an engine, one that used a mixture of hydrogen and oxygen to generate energy.
This spawned the birth of a number of designs based on the internal combustion engine in the early nineteenth century with little or no degree of commercial success. In 1860 thereafter, Jean Joseph Etienne Lenoir built the first successful two-stroke gas driven engine. In 1862 he again built an experimental vehicle driven by his gas-engine, which ran at a speed of 3
km/h. These cars became popular and by 1865 could be frequently seen on the roads.
The first American automobiles with gasoline-powered internal combustion engines were completed in 1877 by George Baldwin Selden of Rochester, New
York, who applied for a patent on the automobile in 1879. Selden received his patent and later sued the Ford Motor company for infringing his patent.
Henry Ford was notoriously against the American patent system, and Selden’s case against Ford went all the way to the Supreme Court, who ruled that
Ford had to pay a penalty to Selden, but could continue manufacturing automobiles, because the technology had changed quite a bit by that time.
Meanwhile, notable advances in steam power evolved in Birmingham, England by the Lunar Society. It was here that the term horsepower was first used.
It was in Birmingham also that the first British four wheel petrol-driven automobiles were built in 1895 by Frederick William Lanchester who also patented the disc brake in the city. Electric vehicles were produced by a small number of manufacturers.
Innovation
The first automobile patent in the United States was granted to Oliver
Evans in 1789; in 1804 Evans demonstrated his first successful self-
propelled vehicle, which not only was the first automobile in the USA but was also the first amphibious vehicle, as his steam-powered vehicle was able to travel on wheels on land and via a paddle wheel in the water.
On 5 November 1895, George B. Selden was granted a United States patent for a two-stroke automobile engine (U.S. Patent 549160). This patent did more to hinder than encourage development of autos in the USA. A major breakthrough came with the historic drive of Bertha Benz in 1888. Steam, electric, and gasoline powered autos competed for decades, with gasoline internal combustion engines achieving dominance in the 1910s.
The large scale, production-line manufacturing of affordable automobiles was debuted by Oldsmobile in 1902, then greatly expanded by Henry Ford in the 1910s. Early automobiles were often referred to as ‘horseless carriages’, and did not stray far from the design of their predecessor.
Through the period from 1900 to the mid 1920s, development of automotive technology was rapid, due in part to the hundreds of small manufacturers competing to gain the world’s attention. Key developments included electric ignition and the electric self-starter (both by Charles Kettering, for the
Cadillac Motor Company in 1910-1911), independent suspension, and four-
wheel brakes.
By the 1930s, most of the technology used in automobiles had been invented, although it was often re-invented again at a later date and credited to someone else. For example, front-wheel drive was re-introduced by Andre
Citroën with the launch of the Traction Avant in 1934, though it appeared several years earlier in road cars made by Alvis and Cord, and in racing cars by Miller (and may have appeared as early as 1897). After 1930, the number of auto manufacturers declined sharply as the industry consolidated and matured.
Since 1960, the number of manufacturers has remained virtually constant, and innovation slowed. For the most part, „new” automotive technology was a refinement on earlier work, though these refinements were sometimes so extensive as to render the original work nearly unrecognizable.
The chief exception to this was electronic engine management, which entered into wide use in the 1960s, when electronic parts became cheap enough to be mass-produced and rugged enough to handle the harsh environment of an automobile. Developed by Bosch, these electronic systems have enabled automobiles to drastically reduce exhaust emissions while increasing efficiency and power.
Model changeover and design change
Cars are not merely continually perfected mechanical contrivances; since the 1920s nearly all have been mass-produced to meet a market, so marketing plans and manufacture to meet them have often dominated automobile design.
It was Alfred P. Sloan who established the idea of different makes of cars produced by one firm, so that buyers could „move up” as their fortunes improved. The makes shared parts with one another so that the larger production volume resulted in lower costs for each price range. For example, in the 1950s, Chevrolet shared hood, doors, roof, and windows with
Pontiac; the LaSalle of the 1930s, sold by Cadillac, used the cheaper mechanical parts made by the Oldsmobile division.
He also conceived of the notion of the yearly model change-over, which became a three-year cycle. In the second year of the cycle, the superficial appearance of the cars changed incidentally; for the third, major changes took place, e.g., the fender dies for the 1957 Chevrolet had to be modified to produce thin, pointed fins and squarish headlamp housings. In the next cycle, the doors, roof, trunk, and often the suspension would have to be redesigned. Factories and the yearly work schedule had to be specialized to accommodate these changeovers.
Such patterns became dominant for the Big Three automakers in the U.S., though European firms neither amalgamated nor could afford the changeover.
After the 1950s, when American firms tackled the technical problems of high-
compression V8, automatic transmissions, and air conditioners, investment shifted to meeting the market for non-technical matters. This was criticized as „planned obsolescence,” although by this it was meant that the car would simply be made to go out of style rather than really being technically surpassed. For example, only those few American cars of the
1960s with front-wheel drive or a rear engine had a fully independent rear suspension because the Hotchkiss drive was cheaper, and people were used to it. Such bad investment left American firms unprepared for the Oil Crisis of the 1970s and the rise of imported luxury cars in the 1980s.
Regulation
In almost every nation, laws have been enacted governing the operation of motor vehicles. Most of this legislation, including limits on allowable speed and other rules of the road, are designed to ensure the smooth flow of traffic and simultaneously protect the safety of vehicle occupants, cyclists, and pedestrians.
In 1965, in the U.S. state of California, state legislation was introduced to regulate exhaust emissions, the first such legislation in the world.
Answering this new interest in environmental and public safety issues, the
Department of Transportation (DOT) and the Environmental Protection Agency
(EPA) both introduced legislation in 1968 which substantially altered the course of automotive development. Since the U.S. market was the largest in the world (and California the largest market in the U.S.), manufacturers worldwide were forced to adapt. For the first time, safety devices were mandatory, as were controls on harmful emissions. Prior to this legislation, even seat belts were considered extra-cost options by many manufacturers. Other countries followed by introducing their own safety and environmental legislation. In time, meeting regulations became the main challenge for the engineers designing new cars. In the decade from 1975 to
1985, the world’s manufacturers struggled to meet the new regulations, some producing substandard cars with reduced reliability as a result. However, by the end of this period, everyone had learned how to handle the newly regulated environment. The manufacturers discovered that safety and environmentalism sold cars, and some began introducing environmental and safety advances on their own initiative.
Environmental changes
The automobile is one of the most destructive modern influences on the environment. For a large part of its development, no consideration was given to concerns such as air pollution, destruction caused by road-
building, and the massively increased consumption of limited natural resources, most notably petroleum. Some of these concerns are now starting to be addressed in some parts of the world. European Union is the leader in that, and it has many possibilities to do so, for example because the cities in Europe are planned to pedestrians and mass transit, before the automobile became common
The Facts about Car Exhausts
What is exhaust pollution?
Your car runs by burning petrol or diesel (a complex blend of lots of different chemicals collectively called hydrocarbons) to produce harmless carbon dioxide and water. There are, however, some by products of this process.
Some of these hydrocarbons do not get burned in your engine and pass through the exhaust unchanged. There are two in particular, called benzene and 1:3 butadiene that can be harmful. Not all the fuel burns up completely, so some carbon monoxide (CO) is also produced. These are the main pollutants produced by older, petrol driven cars, with diesels of all kinds burning their fuel much more completely, so producing negligible amounts of them.
In the 1980s, there was a move towards „lean burn” petrol engine technology
— increasing the amount of air with the fuel in the engine so that more of the fuel is completely burned up. This reduces the amount of the first two pollutants but tends to encourage the oxygen and nitrogen in the air to combine to produce nitrogen oxides (NOx).
If your petrol car was registered after 1993, it will be fitted with a catalytic converter which removes 95% of these three pollutants from the exhaust as compared with a similar 1976 model.
Exhausts can also contain sulphur dioxide (SO2) from impurities in the fuel, but only 3% of the total emissions of this substance come from transport, the rest mainly from industry and power generation.
Recently, a health threat has been identified from particulates, or PM10s, which are microscopic soot particles produced in the combustion process.
Very little particulate emission (5%) is from petrol engines, though, with much more (19%) coming from diesels, disproportionately from the larger diesels in trucks and buses. The National Environmental Technology Centre
(NETCEN) recently suggested that one bus can produce as many particulates as 128 typical cars.
The final element in exhaust pollution is Ozone (O3). This is not emitted directly but made in the air by the action of sunlight on other pollutants to form „ground level Ozone”, which, unlike the „Ozone Layer” in the high atmosphere, is regarded as a bad thing if levels are too high. Ozone is actually broken down by Nitrogen Oxides, so one tends to be lower where the other is higher.
Are these pollutants dangerous?
Most toxic substances are only dangerous when a certain level is exceeded.
Your medicine cupboard is full of chemicals which are beneficial if taken as prescribed by your doctor but which will kill you if you swallow the whole bottle. Many everyday items are poisonous if taken to excess —
Vitamin A, for example, is an essential part of your diet, and lack of it is what kills hunger strikers. A Polar Bear’s liver, on the other hand, contains a lethal dose of Vitamin A!
Four of the pollutants described above (Nitrogen Oxides, Carbon Monoxide,
Sulphur Dioxide, and Ozone) are like this — there are accepted levels at which no harmful effects are observed even in sensitive population groups.
For the other three (Benzene, 1:3 butadiene and particulates) there is no way of proving they are safe at any level, so the experts set standards where the risk to health are „exceedingly small” — in other words they can’t actually measure it!
What are the levels of these pollutants?
The graphs shown below compare the safe levels for these pollutants with the average across both the urban and rural measuring sites shown on Ceefax at 7pm on Friday 27 March this year. This is likely to be a worst case scenario, being right at the end of a Friday rush hour. The worst location is also shown. This is only one day, but if you check the figures regularly you will see that they are entirely typical of peak hour levels.
AIR QUALITY LEVELS AT 7pm, 27 MARCH 1998 vs SAFE LIMITS
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Alternative fuels and batteries
With heavy taxes on fuel, particularly in Europe and tightening environmental laws, particularly in California, and the possibility of further restrictions on greenhouse gas emissions, work on alternative power systems for vehicles continues.
Diesel-powered cars can run with little or no modification on 100% pure biodiesel, a fuel that can be made from vegetable oils. Many cars that currently use gasoline can run on ethanol, a fuel made from plant sugars.
Most cars that are designed to run on gasoline are capable of running with
15% ethanol mixed in, and with a small amount of redesign, gasoline-powered vehicles can run on ethanol concentrations as high as 85%. All petrol fuelled cars can run on LPG. There has been some concern that the ethanol-
gasoline mixtures prematurely wear down seals and gaskets. Further, the use of higher levels of alcohol requires that the automobile carry/use twice as much. Therefore, if your vehicle is capable of 300 miles on a 15-gallon tank, the efficiency is reduced to approximately 150 miles. Of course, certain measures are available to increase this efficiency, such as different camshaft configurations, altering the timing/spark output of the ignition, or simply, using a larger fuel tank.
In the United States, alcohol fuel was produced in corn-alcohol stills until Prohibition criminalized the production of alcohol in 1919. Brazil is the only country which produces ethanol-running cars, since the late 1970s.
Attempts at building viable battery-powered electric vehicles continued throughout the 1990s (notably General Motors with the EV1), but cost, speed and inadequate driving range made them uneconomical. Battery powered cars have used lead-acid batteries which are greatly damaged in their recharge capacity if discharged beyond 75% on a regular basis and NiMH batteries.
Current research and development is centered on „hybrid” vehicles that use both electric power and internal combustion. The first hybrid vehicle available for sale in the USA was the Honda Insight. As of 2005, The car is still in production and achieves around 60 mpg.
Future of the car
There will always be a strong demand for the door-to-door, on-demand service but there are likely to be radical changes in the cars of the future.