UNIT 28: MECHANICS AND
MAINTENANCE LATEST UPDATE
c first self-propelled vehicle - built in Paris in 1769 by the French engineer Nicolas Joseph Cugnot. It was a
heavy, three-wheel carriage that was powered by a large boiler attached to the front of the car.
How most self-propelled vehicles were powered by - For the rest of the 18th and most of the 19th
century, most self-propelled vehicles were powered by steam or electricity. Finally, in 1885, German
mechanical engineer Karl Benz designed and built the first practical automobile using the technology still
most common today: the internal-combustion engine.On January 29, 1886, Benz received the first
patent (DRP No. 37435) for his gas-fueled car.
The first traffic death - Another German engineer, Gottlieb Daimler, was also working on a car, with an
improved version of the internal-combustion engine, in 1885.By 1894, motor vehicles were common
enough that the first Grand Prix race could be held.
However, this auspicious event was soon followed by a tragic one: in 1896, the first traffic death occurred
when Bridget Driscoll, a mother of two, was killed by a car when she stepped into the street. Upon her
death, the coroner stated, "I trust that this sort of nonsense will never happen again."
The most well-known American manufacturers of steam-driven automobiles - Stanley brothers of
Massachusetts. They produced their Stanley Steamers from 1897 until after World War I.Within a few
years, however, American manufacturers would begin to mass produce cars with internal-combustion
engines. These men included Henry Ford, who founded the Ford Motor Company in 1903, proclaiming, "I
will build a car for the great multitude."
October 1908 - In October 1908, Henry Ford made good on his promise, introducing the Model T at a
price of $950. By 1927, the year it was discontinued in favor of other models, the price had reached as
low as $280, a single car could be assembled in 93 minutes, and over 15 million Model Ts had been sold
in the United States alone.The Model T heralded the beginning of the motor age. By the 1920s, the
automobile had evolved from a novelty used mostly by the well-to-do to an essential form of
transportation for the ordinary citizen.
General Motors - Ford's main competition which became the world's largest automobile manufacturer
Domination of automobiles - American manufacturers dominated the automobile industry until the
1970s, when they began to be challenged by the growing sales of Japanese and German cars. Today,
while China has become the world's leading producer of automobiles, American manufacturers remain
on the cutting edge of automotive innovation.
Cultural shifts made possible by the automobile - Increased mobility of the US population
Accelerated development of remote areas
Major population growth in urban areas and the explosion of suburbs
, Increased access to goods and services, and to better education and health care
The replacement of brick streets with asphalt roads
the year when emissions regulations were introduced and seat belts became mandatory - However,
while automobiles have changed American society in positive ways, they have also caused enduring
problems. Cars have led to increased urban sprawl and air and water pollution, and continue to
contribute to thousands of traffic deaths in the U.S. each year.
Indeed, since 1965, when emissions regulations were introduced and seat belts became mandatory,
automobile manufacturers have focused on innovations aimed at reducing the social costs of cars
themselves.
ways of minimizing the social and economic impacts of automobiles - Increased fuel efficiency
Decreased vehicle emissions
Electric and hybrid cars
Integrated vehicle systems
Safety features to minimize the impacts of collisions
Body-on-frame approach - allows manufacturers to make changes to the bodywork and interior while
keeping the chassis unchanged.
While frames were found universally in older automobiles, today many cars use lighter and more crash-
resistant unibody designs that do not need a frame. Frames are now used mostly in truck and bus
construction.
Unibody design - In unibody cars, all the vehicle's components are attached to the body and floorpan
that provide the vehicle's structure. Because a heavy frame is unnecessary in these designs, they weigh
less and can be built more cheaply. Traditionally, the body of a car was built of steel sections, although
modern car bodies often make use of lighter materials, including aluminum, durable plastic, and carbon
fiber. These lighter materials make for better fuel efficiency while still ensuring that vehicle occupants
remain well protected.
Engine - produces the drive power that propels a vehicle forward or backwards. Today, engines can be
found in many configurations, including 4-cylinder, 6-cylinder, and 8-cylinder (V8) engines. The more
cylinders there are in an engine, the more power it will have. Each cylinder has its own piston, each of
which is connected to a single crankshaft that propels the vehicle.
four-stroke combustion cycle - In each cylinder:
The piston moves down, drawing in a fuel-air mixture.
The piston moves up, compressing the fuel-air mixture to make it more explosive.