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The motor car first appeared in Germany in 1885 when Karl Benz and
Gottlieb Daimler, each working independently of the other, produced
self-propelled vehicles powered by rear-mounted, petrol-fuelled
single-cylinder engines. These were based on the stationary gas engine
that used the four-stroke principle.
The replicas of the originals that each engineer produced gave birth to
the world’s motor industry, although in 1896, France and not Germany
became the world’s largest manufacturer of motor vehicles. In 1891 a
French engineer, Emile Levassor, transferred the engine of the Panhard
et Levassor car from its established rear location to the front of the
vehicle, from where it drove the rear wheels via a clutch and in-line
gearbox. Named Systeme Panhard, it rapidly overtook the original layout
in popularity and survives, in essence, on large-capacity cars.
The progressive Gottlieb Daimler soon produced, in 1893, a vertical
two-cylinder in-line engine and Benz followed, in 1897, with a
horizontally opposed twin in which the cylinders were in the same plane
as the crankshaft. Panhard had introduced the in-line four in 1896 and
this configuration soon outstripped all other types in popularity, most
notably in the Henry Ford Model T, built between 1908 and 1927.
Over 15 million of these Fords were produced and their success helped
America to consolidate its position, attained in 1906, as the world’s
largest manufacturer of motor cars. The United States dominated the
industry until 1980, when it was overtaken by Japan.
Britain had lagged behind France and Germany in introducing the motor
car, as its industry was stifled by the presence of the Locomotive Act
of 1865. This required self-propelled vehicles to be limited to a speed
of 3.2 km/h (2 mph) in towns and 6.2 km/h (4 mph) elsewhere. Originally,
motor cars were required to be preceded by a man carrying a red flag but
this stipulation was usually set aside following an amendment to the act
in 1878.
As early cars were capable of at least 32 km/h (20 mph), Continental
imports could not be practically or legally run on Britain’s roads
until 1896, when the Locomotive Act was modified. The speed limit was
raised to a blanket 19 km/h (12 mph) and increased again, in 1904, to 32
km/h (20 mph).
Britain’s motor industry therefore dates from 1896, although most
manufacturers were initially only responsible for their vehicles’
mechanical components. Bodywork, usually of the open type with only
rudimentary weather protection in the form of a canvas hood, was the
responsibility of coachbuilders, who had hitherto manufactured
horse-drawn vehicles.
In 1904 the English Napier company had built the world’s first usable
six-cylinder car, although the costly straight-eight engine did not make
any impact until after World War I. The more compact V8, in which four
in-line cylinders were positioned in a V-shaped configuration, was
popularized by the American Cadillac company in 1915. Its Lincoln rival
was responsible for the world’s first successful V12-engined car that
dates from 1915. However, the V6 unit, pioneered by Lancia, did not
arrive until 1950.
Q Saloon Bodies
Most cars were fitted with open, wooden-framed, hand-crafted steel or
aluminium bodywork that was mounted on a separate chassis frame. Saloons
were more expensive because they used more materials. It was not until
1925 that the American Essex company risked all by offering a closed car
that sold for less than a touring vehicle. The gamble paid off and the
rest of the motoring world soon followed suit.
Machine-made pressed steel body panels had been used by Dodge in America
from 1916; this led to the all-steel saloon and, finally, the unitary
body, which dispensed with the chassis and transferred stresses to the
hull. Citroën’s advanced front-wheel drive Traction Avant model of
1934 was the first mass-produced car to feature the concept and was
followed by General Motors’ German Opel subsidiary in 1935. General
Motors was also responsible for introducing silent gear changes to
motoring in 1928, and in 1940 an American car, the Oldsmobile, was the
first vehicle to have automatic transmission.
Cars used leaf springs inherited from horse-drawn carriages until the
1930s, when independent front suspension was developed. However, its
rear equivalent was rarer and usually confined to more expensive
vehicles. An exception was provided by Volkswagen AG in Germany. The
Beetle was the Volkswagen which was designed by Ferdinand Porsche in
1934 and entered series production in 1945. Featuring all-independent
suspension, it was powered by a rear-mounted, horizontally opposed,
four-cylinder engine that was cheap to run, and which also defied
convention by being air- rather than water-cooled. The Beetle became the
most popular car in the history of motoring; it is still in production
and a record 21 million have been built.
A German company also produced the economical and efficient diesel
engine, invented in 1893 by Rudolf Diesel. Adopted in the 1920s for use
in commercial vehicles, in 1935 Mercedes-Benz introduced the 260D as the
world’s first diesel-engined car.
R Front-Wheel Drive
In 1937 the French Citroën company briefly offered a diesel option in
its front-wheel drive Traction Avant. This model represented the first
serious challenge to the orthodox front-engine/rear-drive configuration.
Although the mechanics were more sophisticated, the Traction Avant
cornered better and could be built with lower body lines because there
was no obtrusive transmission tunnel.
While the Citroën’s engine was conventionally positioned, the British
Motor Corporation’s front-wheel drive Mini of 1959, designed by its
chief engineer Alec Issigonis, had its power unit turned 90° to a
transverse-mounted location. This allowed for more passenger
accommodation: four adults could be seated in a car only 3 m (10 ft)
long.
S Fuel Economy
In Europe Mini-inspired cars became increasingly popular and the Mini
itself became a classic. However, the global influence of the Issigonis
approach attained its height following the oil price rises in the early
1970s. This resulted in a trend in designing and producing smaller
front-wheel drive cars with hatchback bodies, so called because they
incorporated a single opening tailgate. (It also marked a decline in
production of the vast American “gas-guzzlersâ€Â, which had been so
popular in the 1950s.) These cars currently dominate the world market.
The soaring price of petrol also revived research, dormant on passenger
cars since the 1930s, into more aerodynamically efficient bodywork. This
meant that a car’s styling was contoured to assist its passage through
the air in order to minimize petrol consumption. This had hitherto been
the preserve of sports-car makers.
T Performance and Four-Wheel Drive
Lamborghini GTV 350 The Lamborghini 350 GTV was introduced to the public
at the 1963 Turin Motor show. It was made of steel and aluminium panels
over a chassis of round tubes. Despite many critics, the car got a lot
of attention from the press because of its very modern
chassis.Farabolafoto
From the 1970s the performance of such vehicles had also been enhanced
by the development of the turbocharger. Driven by otherwise wasted
exhaust gases, it is a small, high-revolution pump that forces air into
the cylinders at pressure and is invariably used in conjunction with an
intercooler. This cools incoming air to make it denser, further
increasing engine power.
Performance cars were usually front-engined (and sometimes rear-engined)
until the appearance, in 1966, of the Lamborghini Muira, which had a
mid-located power unit. This meant a better-balanced car, but at the
expense of greater interior noise and loss of rear seating.
Yet a further development in performance was the four-wheel drive with
superior road holding. This was a luxury fitment until the arrival, in
1980, of the Audi Quatto, a make that had also introduced, in 1976, the
petrol-fuelled five-cylinder engine. Four-wheel drive had already been
incorporated in the cross-country Land Rover, its design inspired by the
American Jeep. It first appeared in 1948 and paved the way to the
better-equipped Range Rover.
U Further Developments
U1 Reducing Car Emissions
Traffic Pollution The world s roads currently accommodate over 500
million motor vehicles. Most concern about traffic pollution has been
expressed in relation to busy inner-city areas, where high vehicle flows
and large numbers of pedestrians share the same streets. The worst
conditions are experienced when there is a combination of dense traffic
and hot weather without winds.Wesley Bocxe/Photo Researchers, Inc.
In recent years environmental considerations and growing concern over
traffic pollution have had a profound effect on car design. The United
States introduced the first regulations on noxious car emissions in
1967; the California Clean Air Act requires that, by 2003, 10 per cent
of all new cars sold in that state must have zero exhaust emissions.
However, as these restrictions become more rigorous, their effects on
the power and efficiency of car engines grow more adverse. Noxious
emissions include carbon monoxide, nitrogen oxides, volatile organic
compounds, and particulates. In 1986 the Japanese Toyota company
introduced the more efficient multivalve twin overhead camshaft engine,
a unit more usually associated with high-performance models. This
concept has now been widely adopted by the world’s motor industries.
All new cars sold in Europe since 1990 have had to be capable of running
on unleaded petrol. Lead has been added to petrol since the 1920s to
improve engine performance, but was found to be a health hazard when
emitted from car exhausts. In Britain unleaded fuels account for 67 per
cent of petrol sales.
Similarly, the exhaust systems of all new cars have had to be fitted
with catalytic converters since 1993. In its basic two-way form, the
catalytic converter uses platinum and palladium to catalyse the carbon
monoxide and hydrocarbons that are produced by the engine’s combustion
process into carbon dioxide and water.
Manufacturers are currently undertaking research into “lean-burnâ€Â
engines, which use less petrol and therefore produce a lower level of
harmful emissions. The diesel-engined car has grown in popularity but
recent evidence shows that the minute specks of soot, called
particulates, that it produces are likely to exacerbate conditions such
as bronchitis and asthma, mostly in city centres.
U2 Safety
Crash Test Dummy Dummies, such as this one, are used in tests to provide
data regarding the movement of passengers in simulated car crashes, thus
enabling manufacturers to make improvements in the safety of their
vehicles.Paul Almasy/Corbis
Although cars have become faster, current models are safer than many of
those manufactured in previous decades. Modern cars incorporate beams at
their front and rear, which crumple progressively in order to absorb
energy, while having a strong central cell to protect occupants in the
event of a crash.
Braking has greatly improved in recent years and most systems feature
servo assistance. This harnesses the vacuum produced by the engine to
actuate the brakes, so that the driver does not need to apply an
excessive amount of pressure to the pedal.
A further refinement is an automatic braking system. This sophisticated
anti-locking device operates in conjunction with the vehicle’s engine
management unit, and was initially used on expensive cars to prevent
skidding.
U3 Electric Cars
Electric Car: The Zoom Among electric cars, the vehicle ZOOM©, a
prototype electric car for city use, contains many technological
innovations, including a variable wheelbase. Designed and built by MATRA
AUTOMOBILE©, ZOOM© received public attention at its introduction in
1992.Matra Automobile
The only vehicle to meet the requirements of the California Clean Air
Act is the electric car. This type of car produces no harmful exhaust
fumes, and does not absorb power when stationary. In 1996 General Motors
became the world’s first major car manufacturer to put a
purpose-designed electric car, the EV1, into production
Benz, Karl (1844-1929), German mechanical engineer, born in Karlsruhe.
He was a pioneer in the motor industry. In 1878 he developed a two-cycle
internal-combustion engine and later a light four-cycle engine. He
invented the differential drive and other automotive accessories. In
1885 he built a three-wheeled vehicle with an internal-combustion
engine. This vehicle was patented and driven through the streets of
Munich in 1886. Benz shared with the German Gottlieb Daimler the credit
for building the first car.