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Дороги и транспортные средства
Стр 1 из 25Следующая ⇒
Дороги и транспортные средства
Автомобили: история и современность.
По английскому языку
УДК 656 (076.5) =111
Рецензент кандидат филологических наук, доцент Пономарева М.Н.,
кандидат филологических наук, Пономарев В.В.
Д 68 Учебно-методическое пособие по английскому языку для студентов 2 курса направлений 23.03.03 «Эксплуатация транспортно-технологических машин и комплексов», 23.03.01 «Технология транспортных процессов» очной и заочной форм обучения/сост. М.Н. Пономарева, Н.А.Старостина; ООО «Технологии рекламы», г. Москва, 2017. – 96с.
В первой части пособия приведены 10 аутентичных текстов, взятых из электронной энциклопедии «Британника 2001». Тексты, сопровождающиеся словарями и упражнениями.
Во второй части пособия содержатся 10 текстов из области истории автомобилестроения, теоретической механики, гидравлики, гидравлического привода. Тексты сопровождаются словарем, вопросами на проверку общего понимания текста и упражнениями на знание лексических единиц по теме.
В третьей части пособия приведены 10 аутентичных текстов по экологической тематике, взятых из электронной энциклопедии «Британника 2001». Тексты, сопровождающиеся словарями и упражнениями.
Основной целью пособия является развитие навыков чтения, а также навыков устной речи, развитие навыков извлечения информации, ее обработки и получения дополнительных знаний из соответствующих областей технической науки.
ББК 81.2 Англ - 923
©ООО «Технологии рекламы», 2017
©Пономарева М.Н., Старостина Н.А., 2017
Дороги и транспортные средства древних цивилизаций
ROADS OF ANTIQUITY
The first roads were paths made by animals and later adapted by humans. The earliest records of such paths have been found around some springs near Jericho and date from about 6000 BC. The first indications of constructed roads date from about 4000 BC and consist of stone-paved streets at Ur in modern-day Iraq and timber roads preserved in a swamp in Glastonbury, England. During the Bronze age, the availability of metal tools made the construction of stone paving more feasible; at the same time, demand for paved roads rose with the use of wheeled vehicles, which were well established by 2000 BC.
At about this time the Minoans on the island of Crete built a 30-mile (50 kilometre) road from Gortyna on the south coast over the mountains at an elevation of about 4,300 feet (1,300 metres) to Knossos on the north coast. Constructed of layers of stone, the roadway took account of the necessity of drainage by a crown throughout its length and even gutters along certain sections. The pavement, which was about 12 feet (360 centimetres) wide, consisted of sandstone bound by a clay-gypsum mortar. The surface of the central portion consisted of two rows of basalt slabs 2 inches (50 millimetres) thick. The centre of the roadway seems to have been used for foot traffic and the edges for animals and carts. It is the oldest existing paved road.
CHINA ’S IMPERIAL HIGHWAY
China had a road system that paralleled the Persian Royal Road and the Roman road network in time and purpose. Its major development began under Emperor Shih huang-0 about 220 BC. Many of the roads were wide, surfaced with stone, and lined with trees; steep mountains were traversed by stone-paved stairways with broad treads and low steps. By AD 700 the network had grown to some 40,000 kilometres. Traces of a key route near Slan are still visible.
The Silk Road
The trade route from China to Asia Minor and India, known as the Silk Road, had been in existence for 1,400 years at the time of Marco Polo's travels (c. AD 1270-90). It came into partial existence about 300 BC, when it was used to bring jade from Khotan (modern Ho-t'ien) to China. By 200 BC it was linked to the West, and by 100 BC it was carrying active trade between the two civilizations. At its zenith in AD 200 this road and its western connections over the Roman system constituted the longest road on earth. In Asia the road passed through Samarkand to the region of Fergana, where, near the city of Osh, a stone tower marked the symbolic watershed between East and West. From Fergana the road traversed the valley between the Tien Shan and Kunlun mountains through Kashgar, where it divided and skirted both sides of the Takia Makan Desert to join again at Ansi. The road then wound eastward to Chia-yu-kwan (Su-chou), where it passed through the westernmost gateway (the Jade Gate or Yumen) of the Great Wall of China. It then went southeast on the Imperial Highway to Slan and eastward to Shanghai on the Pacific Ocean. From Kashgar, trade routes to the south passed over the mountains to the great trading centre of Bactria and to northern Kashmir.
THE ROMAN ROADS
The greatest systematic road builders of the ancient world were the Romans, who were very conscious of the military, economic, and administrative advantages of a good road system. The Romans drew their expertise mainly from the Etruscans—particularly in cement technology and street paving—though they probably also learned skills from the Greeks (masonry), Cretans, Carthaginians (pavement structure), Phoenicians, and Egyptians (surveying). Concrete made from cement was a major development that permitted many of Rome's construction advances.
The Romans began their road-making task in 334 BC and by the peak of the empire had built nearly 53,000 miles of road connecting their capital with the frontiers of their far-flung empire. Twenty-nine great military roads, the viae militares, radiated from Rome. The most famous of these was the Appian Way. Begun in 312 BC, this road eventually followed the Mediterranean coast south to Capua and then turned eastward to Beneventum, where it divided into two branches, both reaching Brundisium (Brindisi). From Brundlslum the Appian Way traversed the Adriatic coast to Hydruntum, a total of 410 miles from Rome.
The typical Roman road was bold in conception and construction. Where possible, it was built in a straight line from one sighting point to the next, regardless of obstacles, and was carried over marshes, lakes, ravines, and mountains. In its highest stage of development, it was constructed by excavating parallel trenches about 40 feet apart to provide longitudinal drainage—a hallmark of Roman road engineering. The foundation was then raised about three feet above ground level, employing material taken from the drains and from the adjacent cleared ground. As the importance of the road increased, this embankment was progressively covered with a light bedding of sand or mortar on which four main courses were constructed: the statumen layer 10 to 24 inches (250 to 600 millimetres) thick, composed of stones at least 2 inches in size, the rudus, a 9-inch-thick layer of concrete made from stones under 2 inches in size, the nucleus layer, about 12 inches thick, using concrete made from small gravel and coarse sand, and, for very important roads, the summum dorsum, a wearing surface of large stone slabs at least 6 inches deep. The total thickness thus varied from 3 to 6 feet. The width of the Appian Way in its ultimate development was 35 feet. The two-way, heavily crowned central carriageway was 15 feet wide. On each side it was flanked by curbs 2 feet wide and 18 inches high and paralleled by one-way side lanes 7 feet wide. This massive Roman road section, adopted about 300 BC, set the standard of practice for the next 2,000 years.
The public transport of the Roman Empire was divided into two classes: (1) cursus rapidi, the express service, and (2) agnarie, the freight service. In addition, there was an enormous amount of travel by private individuals. The most widely used vehicles were the two-wheeled chariot drawn by two or four horses and its companion, the cart used in rural areas. A four-wheeled raeda in its passenger version corresponded to the stage coaches of a later period and in its cargo version to the freight wagons. Fast freight raedae were drawn by 8 horses in summer and 10 in winter and, by law, could not haul in excess of 750 pounds, or 330 kilograms. Speed of travel ranged from a low of about 15 miles per day for freight vehicles to 75 miles per day by speedy post drivers.
ROADS OF PERSIA AND BABYLON
The earliest long-distance road was a 1,500-mile route between the Persian Gulf and the Mediterranean Sea. It came into some use about 3500 BC, but it was operated in an organized way only from about 1200 BC by the Assyrians, who used it to join Susa, near the Persian Gulf, to the Mediterranean ports of Smyrna (Izmir) and Ephesus. More a track than a constructed road, the route was duplicated between 550 and 486 BC by the great Persian kings Cyrus II and Darius I in their famous Royal Road. Like its predecessor, the Persian Royal Road began at Susa, wound northwestward to Arbela, and thence proceeded westward through Nineveh to Harran, a major road junction and caravan centre. The main road then continued to twin termini at Smyrna and Ephesus. The Greek historian Herodotus, writing in about 475 BC, put the time for the journey from Susa to Ephesus at 93 days, although royal riders traversed the route in 20 days.
In Babylon about 615 BC the Chaldeans connected the city's temples to the royal palaces with a major Processional Way, a road in which burned bricks and carefully shaped stones were laid in bituminous mortar.
ANCIENT ROADS OF EUROPE
The Amber Routes
During the 2nd millennium BC, trade ways developed in Europe. One route, for example, ran between Italy and Spain via Marseille and nearby Heraclea, close to present-day Avignon. Such ways were used for the movement of flints from Denmark, freestone from Belgium, salt from Austria, lead and tin from England, and amber from northern Europe. By about 1500 BC many of the ways in eastern and central Europe had linked together into an extensive trading network known as the Amber Routes. Four routes have been identified, the first from modern Hamburg southwestward by dual routes through Cologne and Frankfurt to Lyon and Marseille. The second also passed from Hamburg south to Passau on the Danube and then through the Brenner Pass to Venice. The third began at Samland on the East Prussian coast (where amber is still found), crossed the Vistula River at Thorn, and thence continued southeastward through the Moravian Gate to Aqullela on the Adriatic. The fourth, the Baltic-Pontus road, followed the main eastern rivers, the Vistula, Saw, Sereth, Prut, Bug, and Dnieper.
While the Amber Routes were not roads in the modern sense, they were improved at river crossings, over mountain passes, and across wet and swampy areas. A few remnants of these roads survive today. They were constructed by laying two or three strings of logs in the direction of the road on a bed of branches and boughs up to 20 feet (6 metres) wide. This layer was then covered with a layer of transverse logs 9 to 12 feet in length laid side by side. In the best log roads, every fifth or sixth log was fastened to the underlying subsoil with pegs. There is evidence that the older log roads were built prior to 1500 BC. They were maintained in a level state by being covered with sand and gravel or sod. In addition, the Romans used side ditches to reduce the moisture content and increase the carrying capacity.
INCA ROADS OF SOUTH AMERICA
Across the Atlantic, the period witnessed the rise of another notable road-building empire, that of the Incas. The Inca road system extended from Quito, Ecuador, through Cuzco, Peru, and as far south as Santiago, Chile. It included two parallel roadways, one along the coast about 2,250 miles in length, the other following the Andes about 3,400 miles in length with a number of cross connections. At its zenith, when the Spaniards arrived early In the 16th century, a network of some 14,000 miles of road served an area of about 750,000 square miles (1,940,000 square kilometres) in which lived nearly 10 million people. The network was praised by 16th-century explorers as superior to that in contemporary Europe. The Andes route was remarkable. The roadway was 25 feet wide and traversed the loftiest ranges. It included galleries cut into solid rock and retaining walls built up for hundreds of feet to support the roadway. Ravines and chasms were filled with solid masonry, suspension bridges with wool or fibre cables crossed the wider mountain streams, and stone surfacing was used in difficult areas. The steeper gradients were surmounted by steps cut in the rocks. Traffic consisted entirely of pack animals (llamas) and people on foot; the Inca lacked the wheel. Yet they operated a swift foot courier system and a visual signaling system along the roadway from watchtower to watchtower.
FIRST WHEELED VEHICLES
After the early efforts to domesticate animals for their burden-carrying abilities, the next significant addition to human locomotion was the wheeled vehicle. It was one of the great inventions of all time because of the contribution that the wheel, and its utilisation in a vehicle, makes to applying supplemental sources of power to an individual's mobility. Horses and camels can travel faster than the humans riding on their backs, but to transport more than one person with a single animal - something most horses had the strength to do - a vehicle was needed. Probably the first conveyance of this sort was a plank or log dragged along the ground; the Plains Indians of North America used such a travois of two poles in their transhumant wanderings until the 19th century. Its mechanical inefficiency must have prompted the search for improvements. The invention of the wheel made the contribution of a horse more productive. The power provided by any one horse has varied little over time, but the effective product of that horsepower has grown with changes in vehicles, in harnessing, and in the surface on which it operates.
There were several advantages of a two-wheel cart, as compared with the ultimately more common four-wheel variation. The most significant was in steering, particularly if individual wheels rotated independently on an axle. A two-wheel cart could be tipped to aid in loading and unloading, and the shafts on the cart could more readily be adjusted to the height of different animals. Wheels were difficult to make, so limiting their number would have some advantage. In the earliest vehicles of this kind, wheels were probably simple slices across the diameter of a tree, but such proved both limited in size and subject to fracture. Two or three boards nailed together and then cut into a circular shape were easier to construct and stronger than simple slices of logs. The main disadvantage was that either type of wheel was heavy, thus reducing the effective tractive effort of the draft animal. Ultimately the spoked wheel was created to lighten the cart, allowing it either to carry a heavier load or to move at a faster speed.
In putting the cart to use the critical question was how to attach the vehicle to a draft animals. Oxen and zebu cattle were among the earliest draft animals used, and a yoke was attached to their horns. Subsequently a neck yoke took its place as asses, mules, and horses were made to draw vehicles. To harness them, either two animals were put under a yoke attached to the cart by a single pole or a single animal was put between shafts hitched to the cart. Research has shown that the one-pole yoked pair of animals was generally used south of a line which began at the Baltic Sea, trended eastward across southern Russia to the Caspian Sea, and followed the Altai Mountains to the southern Chinese frontier; north of that line a single animal between shafts was employed, a distinction already in evidence by 1000 BC.
Vegetation also played a role: in those parts of Eurasia where trees and stout brush were found, residents were slow to take up carts because paths were likely to be either absent or at best too narrow to permit their passage. A person mounted on horseback might use a narrow path but not a draft animal drawing a cart. Thus it was in the open grassland steppes and deserts that wheeled vehicles first came into use.
The earliest and simplest four-wheel vehicle found in Rome was the plaustrum, which was little more than a flat board borne on four wheels. The firmly attached wheel and the rigidly framed front axle made guiding the wagon cumbersome and rendered the mechanical efficiency of the vehicle very low. These concerns and the poor harnessing of draft animals assured that freight transport by road would be time-consuming and costly.
The Cursus Publicus
The most impressive Roman accomplishment in transportation was what became the postal service, or cursus publicus. At first state runners carried information about and diplomatic instructions to distant corners of the empire. Within a relatively short time mail coaches were established to communicate directly with the provinces. This was not a true public mail service as its use was restricted to persons traveling on business for the emperor or to the rich and powerful.
The use of the cursus publicus was rigidly constrained by regulations on the size and capacity of its vehicles, who might ride on them and for what purposes, who must maintain a vehicle that might be employed in this quasi-public service, and other matters. Because construction and maintenance of roads was costly, they were carefully shielded against overuse, with light maximum loads for various kinds of vehicles. As the Roman Empire lost its vitality, the use of the cursus publicus became subject to favouritism and misuse. With the collapse of the empire the truly exceptional qualities of that system disappeared and did not emerge again until modern times.
HISTORY OF THE AUTOMOBILE
What Was the First Car?
By William W.Bottorff
Several Italians recorded designs for wind driven vehicles. The first was Guido da Yigevano in 1335. It was a windmill type drive to gears and thus to wheels. Vaturio designed a similar vehicle which was also never built. Later Leonardo da Vinci designed a clockwork driven tricycle with tiller steering and a differential mechanism between the rear wheel
A Catholic priest named Father Ferdinand Verbiest has been said to have built a steam powered vehicle for the Chinese Emperor Chien Lung in about 1678. There is no information about the vehicle, only the event. Since Thomas Newcomen built his first steam engine only in 1712, we can guess that this was possibly a model vehicle powered by a mechanism like Hero’s steam engine, a spinning wheel with jets on the periphery.
Newcomen’s engine had a cylinder and a piston and was the first of this kind, and it used steam as a condensing agent to form a vacuum and with an overhead walking beam, pull on a rod to lift water. It was an enormous thing and was strictly stationary. The steam was not under pressure, just an open boiler piped to the cylinder. It used the same vacuum principle that Thomas Savery had patented to lift water directly with the vacuum, which would have limited his pump to less than 32 feet of lift. Newcomen’s lift would have only been limited by the length of the rod and the strength of the valve at the bottom.
Somehow Newcomen was not able to separate his invention from that of Savery and had to pay for Savery’s rights. In 1765 James Watt developed the first pressurized steam engine which proved to be much more efficient and compact than the Newcomen engine.
The first vehicle to move under its own power for which there is a record was designed by Nicholas Joseph Cugnot and constructed by M. Brezin in 1769. A replica of this vehicle is on display at the Conservatoire des Arts et Metiers, in Paris. The Smithsonian Museum in Washington, D. C. also has a large (half size) scale model. A second unit was built in 1770 which weighed 8,000 pounds and had a top speed on 2 miles per hour, and on the cobble stone streets of Paris this was probably as fast as anyone wanted to go it. The early steam powered vehicles were so heavy that they were only practical on a perfectly flat surface as strong as iron. A road thus made out of iron rails became the norm for the next hundred and twenty five years. The vehicles got bigger and heavier and more powerful and as such they were eventually capable of pulling a train of many cars filled with freight and passengers.
Many attempts had been made in England by the 1830’s to develop a practical vehicle that didn’t need rails. A series of accidents and propaganda from the established railroads caused a flurry of restrictive legislation to be passed and the development of the automobile bypassed England. Several commercial vehicles were built but they were more like trains without tracks.
The development of the internal combustion engine had to wait until fuel was available to combust internally. Gunpowder was tried but didn’t work out. Gunpowder carburetors are still hard to find. The first gas really did use gas. They used coal gas generated by heating coal in a pressure vessel or boiler. A Frenchman named Etienne Lenoir patented the first practical gas engine in Paris in 1860 and drove a car based on the design from Paris to Joinville in 1862. His one-half horse power engine had a bore of 5 inches and a 24 inch stroke. It was big and heavy and turned 100 rpm. Lenoir died in 1900.
Lenoir had a separate mechanism to compress the gas before combustion. In 1862, Alphonse Bear de Rochas figured out how to compress the gas in the same cylinder in which it was to bum, which is the way we still do it. This process of bringing the gas into the cylinder, compressing it, combusting the compressed mixture, then exhausting it is known as the Otto cycle, or four cycle engine. Lenoir claimed to have run the car on benzene and his drawings show an electric spark ignition. If so, then his vehicle was the first to run on petroleum based fuel, or petrol, or what we call gas, short for gasoline.
Siegfried Marcus, of Mecklenburg, built a car in 1868 and showed one at the Vienna Exhibition in 1873. His later car was called the Strassenwagen had about 3/4 horse power at 500 rpm. It ran on crude wooden wheels with iron rims and stopped by pressing wooden blocks against the iron rims, but it had a clutch, a differential and a magneto ignition. One of the four cars which Marcus built is in the Vienna Technical Museum and can still be driven under its own power. In 1876, Nokoiaus Otto patented the Otto cycle engine, de Rochas had neglected to do so, and this later became the basis for Daimler and Benz breaking the Otto patent by claiming prior art from de Rochas.
In 1885, in Gottllieb Daimler’s workshop in Bad Cannstatt the wooden motorcycle was built. Daimler’s son Paul rode this motorcycle from Cannstatt to Unterturkheim and back on November 10, 1885. Daimler used a hot tube ignition system to get his engine speed up to 1000 rpm.
The previous August, Karl Benz had already driven his light, tubular framed tricycle around the Neckar valley, only 60 miles from where Daimler lived and worked. They never met. Frau Berta Benz took Karl’s car one night and made the first long car trip to see her mother, travelling 62 miles from Mannheim to Pforzheim in 1888.
Also in August 1888, William Steinway, owner of Steinway & Sons piano factory, talked to Daimler about US manufacturing right and by September had a deal. By 1891 the Daimler Motor Company, owned by Steinway, was producing petrol engines for tramway cars, carriages, quadracycles, fire engines and boats in a plant in Hartford, CT. Steam cars had been built in America since the Civil War but the early ones were like miniature locomotives. In 1871, Dr. J.W. Carhart, professor of physics at Wisconsin State University, and the J. I. Case Company built a working steam car. It was practical enough to inspire the State of Wisconsin to offer a $10,000 prize to the winner of a 200 mile race in 1878. The 200 mile race had seven entries, of which two showed up for the race. One car was sponsored by the city of Green Bay and the other by the city of Oshkosh. The Green Bay car was the fastest but broke down, and the Oshkosh car finished with an average speed of 6 mph.
From this time until the end of the century, nearly every community in America had a mad scientist working on a steam car. Many old news papers tell stories about the trials and failures of these would be inventors.
By 1890 Ransom E. Olds had built his second steam powered car. One was sold to a buyer in India, but the ship it was on was lost at sea. Running by February, 1893, and ready for road trials by September, 1893, the car built by Charles and Frank Duryea, brothers, was the first gasoline powered car in America. The first run on public roads was made on September 21, 1893, in Springfield, MA. They had purchased a used horse drawn buggy for $70 and installed a 4HP, single cylinder gasoline engine. The car (buggy) had a friction transmission, spray carburettor and low tension ignition. It must not have run very well because Frank didn’t drive it again until November 10, when it was reported by the Springfield Morning Union newspaper. This car was put into storage in 1894 and stayed there until 1920 when it was rescued by Inglis M. appreciated and presented to the United States National Museum.
Honda Motor Co., Ltd., or simply called Honda, is a Japanese engine manufacturer and engineering corporation. The company is perhaps most notable for its automobiles and motorcycles, but it also produces a long list of other products: trucks, scooters, robots, jets and jet engines, water craft, electrical generators, marine engines, lawn and garden equipment, and aeronautical and other mobile technologies. Honda’s high-end line of cars are branded Acura in North America and China. More recently they have ventured into the world of mountain bikes, producing the very first bike to use an internal gear changing system in the Honda RN-01 G-cross. With more than 14 million internal combustion engines built each year, Honda is the largest engine-maker in the world. In 2004, the company began to produce diesel motors, which were very quiet whilst not requiring particulate filters to pass pollution standards. It is arguable, however, that the foundation of Honda’s success is the motorcycle division. Honda is headquartered in Tokyo. Their shares trade on the Tokyo Stock Exchange and the New York Stock Exchange, as well as exchanges in Osaka, Nagoya, Sapporo, Kyoto, Fukuoka, London, Paris and Switzerland. American Honda Motor Co. is based in Torrance, California. Honda Canada Inc. is headquartered in the Scarborough, Ontario district of Toronto, Ontario, and is building new corporate headquarters in Richmond Hill, Ontario, scheduled to relocate in 2008. Honda has also created many joint ventures around the world.
Company history. Soichiro Honda was a mechanic who, after working at Art Shokai, developed his own design for piston rings in 1938. He attempted to sell them to Toyota who did not reject his first design like believed. He constructed a new facility to supply Toyota, but soon after, during World War II, the Honda piston manufacturing facilities were almost completely destroyed.
Soichiro Honda created a new company with what he had left in the Japanese market that was decimated by World War II; his country was starved of monf’ and fuel, but still in need of basic transportation. Honda, utilizing his manufacturing facilities, attached an engine to a bicycle which created a cheap and efficient transport. He gave his company the name Honda Giken Kogyo Kabushiki Kaisha which translates to Honda Research Institute Company, Ltd. Despite its grandiose name, the first facility bearing the name was a simple wooden shack where Mr Honda and his associates uld fit the engines to bicycles. The official Japanese name for Honda )tor Company, Ltd. remains the same in honour of Soichiro Honda’s arts. On 24 September, 1948, the Honda Motor Co. was officially founded Japan. Honda began to produce a range of scooters and motorcycles d Soichiro Honda quickly recovered from the losses incurred during : war. Honda’s first motorcycle to be put on sale was the 1947. A-Type re year before the company was officially founded). However, Honda’s st full-fledged motorcycle on the market was the 1949 Dream D-Type. was equipped with a 98cc engine producing around 3 horsepower. This .s followed by a number of successful launches of highly popular scooters roughout the 1950s.
Porsche AG, or just Porsche, is a German sports car manufacturer, founded in 1931 by Austrian Ferdinand Porsche, the engineer who also created the first Volkswagen. The company is located in Zuffenhausen, a city district of Stuttgart, Baden-Wurttemberg.
History of the company. The first Porsche, the Porsche 64 of 1938, used many components from the Volkswagen Beetle. The second Porsche model and first production automobile, the Porsche 356 sports car of 1948, was built initially in Gmiind, Austria, the location to which the company was evacuated during war times, but after building forty-nine cars the company relocated to Zuffenhausen. Many regard the 356 as the first Porsche simply because it was the first model sold by the fledgling company.
Ferdinand Porsche worked with his son, Ferry Porsche, in designing the 356. Not long afterward, on January 30, 1951, Ferdinand Porsche died from complications following a stroke. The 356 automobile used components from the Beetle including its engine, gearbox, and suspension. The 356, however, had several evolutionary stages, A, B, and C, while in production and many VW parts were replaced by Porsche-made parts. The last 356s were powered by entirely Porsche-designed engines. The sleek bodywork was designed by Erwin Komenda who also had designed the body of the Beetle.
In 1963, after some success in motor-racing, namely with the Porsche 550 Spyder, the company launched the Porsche 911 another air-cooled, rear-engined sports car, this time with a 6-cylinder ‘boxer engine’. The team to lay out the body shell design was led by Ferry Porsche’s eldest son, Ferdinand Alexander Porsche (F. A.). The design phase for the 911 caused internal problems with Erwin Komenda who led the body design department until then. F. A. Porsche complained Komenda made changes to the design not being approved by him. Company leader Ferry Porsche took his son’s drawings to neighbouring body shell manufacturer Reuter bringing the design to the 1963 state. Reuter’s workshop was later acquired by Porsche (so-called Werk II). Afterward Reuter became a seat manufacturer, today known as Keiper-Recaro.
The design group gave sequential numbers to every project (356, 550, etc.) but the designated 901 nomenclature contravened Peugot’s commercial rights on all ‘xOx’ names, so it was adjusted to 911. Racing models adhered to the ‘correct’ numbering sequence: 904, 906, 908. The 911 has become Porsche’s most well-known model, successful on the race-track, in rallies, and in terms of sales. Far more than any other model, the Porsche brand is defined by the 911. It remains in production; however, after several generations of revision, current-model 911s share only the basic mechanical concept of a rear-engined, six-cylinder coupe, and basic styling cues with the original car. A cost-reduced model with the same body, but 356-derived running gear, was sold as the 912.
In 1972, the company’s legal form was changed from limited partnership to private limited company (German AG), because Ferry Porsche and his sister, Louise Piech, felt their generation members did not team up well. This led to the foundation of an executive board whose members came from outside the Porsche family, and a supervisory board consisting mostly of family members. With this change, no family members were in operational charge of the company. F. A. Porsche founded his own design company, Porsche Design, which is renowned for exclusive sunglasses, watches, furniture, and many other luxury articles. Ferdinand Piech, who was responsible for mechanical development of Porsche’s serial and racing cars, formed his own engineering bureau and developed a 5-cylinder-inline diesel engine for Mercedes-Benz. A short time later he moved to Audi and pursued his career through the entire company, up to and including, the Volkswagen Group boards.
The first CEO of Porsche AG was Dr Ernst Fuhrmann who had been working in Porsche’s engine development. Fuhrmann was responsible for the so-called Fuhrmann-engine used in the 356 Carrera models, as well as the 550 Spyder, having four over-head camshafts instead of a central camshaft as in the Volkswagen-derived serial engines. He planned to cease the 911 during the 70s and replace it with the V8-front engined grand sportswagon 928.
In 1990, Porsche drew up a memorandum of understanding with Toyota to learn and benefit from Japanese production methods. Currently Toyota is assisting Porsche with Hybrid technology, rumored to be making its way into a Hybrid Cayenne SUV. Following the dismissal of Bonn, an interim CEO was appointed, longtime Porsche employee, Heinz Branitzki, who served in that position until Dr Wendelin Wiedeking became CEO in 1993. Wiedeking took over the chairmanship of the board at a time when Porsche appeared vulnerable to a takeover by a larger company. During his long tenure, Wiedeking has transformed Porsche into a very efficient and profitable company.
Ferdinand Porsche’s grandson, Ferdinand Piech, was chairman and CEO of the Volkswagen Group from 1993 to 2002. Today he is chairman of the supervisory board. With 12.8 per cent of the Porsche voting shares, he also remains the second largest individual shareholder of Porsche AG after his cousin, F. A. Porsche, (13.6 per cent). Porsche’s 2002 introduction of the Cayenne also marked the unveiling of a new production facility in Leipzig, Saxony, which once accounted for nearly half of Porsche’s annual output. The Cayenne Turbo S has the second most powerful production engine in Porsche’s history, with the most powerful belonging to the Carrera GT. In 2004, production of the 605 horsepower Carrera GT commenced in Leipzig, and at ?450,000 ($440,000 in the United States) it was the most expensive production model Porsche ever built.
As of 2005, the extended Porsche and Pibch families controlled all of Porsche AG’s voting shares. In early October 2005, the company announced acquisition of an 18.53 % stake in Volkswagen AG and disclosed intentions to acquire additional VW shares in the future. In mid-2006, after years of the Boxster (and later the Cayenne) as the dominant Porsche in North America,
In racing, Porsche’s main 1)____has traditionally been Ferrari, though traditionally their 2)____ vehicles appeal to 3)_______ different personalities, if similar demographics. Commercially, Ferrari sells far fewer cars at much 4)_______ prices than Porsche (for example, there are no Ferraris under $ 100,000,
while several Porsches are priced below that 5)______). Porsche’s 6)______ with Ferrari is primarily because of both companies’ storied racing heritage and the fact that some of their vehicles are of 7)______ performance, not because of direct 8)______ between some models. Porsche has a reputation for offering equal or higher performing cars than the more 9)________Ferrari models.
Porsche’s traditional rivals for the daily-driver 10) ________are its fellow German automakers Mercedes-Benz and BMW, who 11)__________more directly with Porsche (example, the Boxster competes directly with the BMW Z4 and the Mersedes-Benz SLK). Ferrari, on the other hand, competes more directly with 12)_________ such as Lamborghini and Aston Martin (companies Porsche only competes nartiallv with Г Porsche also comnetes with Lotus. Jaguar, and Maserati.
THE AUTOMOBILE COMPONENTS
Internal Comhustion Engine
The internal combustion engine in which the combustion (or radip oxidation) of gas and air occurs in a confined space called a combustion chamber. This exothermic reaction of a fuel with an oxidizer creates gases of high temperature and pressure, which are permitted to expand.
The first internal combustion engines did not have compression, but ran on air/fuel mixture sucked or blown in. The most significant distinction between modem internal combustion engines and the early designs is the use of compression and in particular of in-cylinder compression. The term Internal Combustion Engine (ICE) is almost always used to refer specifically to reciprocating engines and similar designs in which combustion is intermittent. However, continuous combustion engines, such as jet engines, most rockets and many gas turbines are also internal combustion engines.
For a typical four-stroke engine, key parts of the engine include the combustion chamber, one or more camshafts, cams and intake and exhaust valves. There are one or more cylinders and for each cylinder there is a spark plug, a piston and a crankshaft. The defining feature of an ICE is that useful work is performed by the expanding hot gases acting directly to cause pressure, further causing movement of the piston inside the cylinder. A single sweep of the cylinder by the piston in an upward or downward motion is known as a stroke. If there are four movements, or strokes, of the piston before the entire engine firing sequence is repeated, we have a typical four-stroke cycle, or Otto cycle.
The cycle begins with the intake stroke as the piston is pulled downward towards the crankshaft. The intake valve is open, and fuel and air are drawn past the valve and into the combustion chamber and cylinder from the intake manifold. At the end of the intake stroke, the piston begins to move back (upward). The cylinder and combustion chamber are full of the low pressure fuel-air mixture and, as the piston begins to move, the intake valve closes. Cams and rocker arms provide control and timing of the valves’ opening and closing.
As the piston is pushed downward again, the volume is reduced and the fuel-air mixture is compressed during the compression stroke. During the compression, no heat is transferred to the fuel-air mixture. As the v olume is decreased because of the piston’s motion, the pressure in the gas is increased. When the volume is the smallest, and the pressure the highest, the contact is closed, and a current of electricity flows through the plug.
At the beginning of the power stroke the spark plug produces a spark in the combustion chamber which ignites the fuel-air mixture. Rapid combustion of the fuel releases heat and produces exhaust gases. Because the intake and exhaust valves are closed, the combustion of the fuel takes place in a totally enclosed and nearly constant volume vessel. The combustion increases the temperature of the exhaust gases, any residual air in the combustion chamber, and the combustion chamber itself.
The high pressure of the gases acting on the face of the piston cause the piston to move downward which initiates the power stroke. Unlike the compression stroke, the hot gas does work on the piston during the power stroke. The force on the piston is transmitted by the piston rod to the crankshaft, where the linear motion of the piston is converted to angular motion of the crankshaft. During the power stroke, the volume occupied by the gases is increased because of the piston’s motion and no heat is transferred to the fuel-air mixture. As the volume is increased, the pressure and temperature of the gas are decreased. Heat that is now transferred to the water in the water jacket until the pressure approaches atmospheric pressure. The exhaust valve is then opened by the cam pushing on the rocker arm to begin the exhaust stroke.
The purpose of the exhaust stroke is to clear the cylinder of the spent exhaust in preparation for another ignition cycle. As the exhaust stroke begins, the cylinder and combustion chamber are full of exhaust products at low pressure. As the piston moves upward, the exhaust gas is pushed past the open exhaust valve and exits the engine. At the end of the exhaust stroke, the exhaust valve is closed and the engine begins another intake stroke.
Internal combustion engines can contain any number of cylinders, with numbers between one and twelve being common. Most car engines have four to eight cylinders, with some high performance cars having ten, twelve, or even sixteen, and some very small cars and trucks having two or three. Having more cylinders in an engine yields two potential benefits. First, the engine can have a larger displacement with smaller individual reciprocating masses (that is, the mass of each piston can be less) thus making a smoother running engine since the latter tends to vibrate as a result of the pistons moving up and down. Second, with a greater displacement and more pistons, more fuel can be combusted and there can be more power strokes in a given period of time, meaning that such an engine can generate more torque than a similar engine with fewer cylinders.
The down side to having more pistons is that the engine will tend to weigh more and tend to generate more internal friction as the greater number of pistons rub against the inside of their cylinders. This tends to decrease fuel efficiency and deprive the engine of some of its power. For high performance engines using modern materials and technology there seems to be a break point around 10 or 12 cylinders, after which addition of cylinders becomes an overall detriment to performance and efficiency, although exceptions such as the W16 engine from Volkswagen exist.
All internal combustion engines must achieve ignition in their cylinders to create combustion and can be classified by their ignition system. The point in the cycle at which the fuel/oxidizer mixture is ignited has a direct effect on the efficiency and output of the ICE. For a typical 4 stroke automobile engine, the burning mixture has to reach its maximum pressure when the crankshaft is 90 degrees after top dead centre. Leaner mixtures and lower mixture pressures bum more slowly requiring more advanced ignition timing. In the past outside flame and hot-tube systems were used. Nikola Tesla gained one of the first patents on the mechanical ignition system with the US patent, ‘Electrical Igniter for Gas Engines’, on 16 August, 1898. Today most engines use an electrical or compression heating system for ignition. Typically engines use either a spark ignition (SI) method or a compression ignition (Cl) system. Ignition components generally include spark plugs, ignition wires, distributor cap, distributor rotor, distributor, ignition coil, ignition module and primary circuit triggering device.
For ignition management, the system also relies on the power train control module (PCM), which also manages other engine functions. The names and exact use of ignition components varies widely among different makes and models. For example, many ignition systems no longer use a distributor and consequently do not have any of its related parts. As a team, the ignition components work together to sense engine position and conditions and provide a spark inside the engine’s cylinders at precisely the right instant.
Electrical or gasoline-type ignition systems (that can also run on other fuels) generally rely on a combination of a lead-acid battery and an induction coil to generate a high-voltage electrical spark to ignite the air-fuel mix in the engine’s cylinders. This battery can be recharged during operation using an electricity-generating device, such as an alternator or generator driven by the engine. Gasoline engines take in a mixture of air and gasoline, compress to less than 185 psi and use a spark plug to ignite the mixture when it is compressed by the piston head in each cylinder.
Compression ignition systems, such as the diesel engine and HCCI engines, rely solely on heat and pressure created by the engine in its compression process for ignition. Compression that occurs is usually more than three times higher than in a gasoline engine. Diesel engines will take in air only, and shortly before peak compression, a small quantity of diesel fuel is sprayed into the cylinder via a fuel injector that allows the fuel to instantly ignite. HCCI type engines will take in both air and fuel but will continue to rely on an unaided auto-combustion process due to higher pressures and heat. This is also why diesel and HCCI engines are also more susceptible to cold starting issues though they will run just as well in cold weather once started. Most diesels also have battery and charging systems however this system is secondary and is added by manufacturers as luxury for ease of starting, turning fuel on and off which can also be done via a switch or mechanical apparatus, and for running auxiliary electrical components and accessories. Most old engines, however, rely on electrical systems that also control the combustion process to increase efficiency and reduce emissions.
HCCI has characteristics of the two most popular forms of combustion used in IC engines: homogeneous charge spark ignition (gasoline engines) and stratified charge compression ignition (diesel engines). As in homogeneous charge spark ignition, the fuel and oxidizer are mixed together.
However, rather than using an electric discharge to ignite a portion of the mixture, the concentration and temperature of the mixture are raised by compression until the entire mixture reacts simultaneously. Stratified charge compression ignition also relies on temperature increase and concentration resulting from compression, but combustion occurs at the boundary of fuel-air mixing, caused by injection.
The defining characteristic of HCCI is that the ignition occurs at several places at a time which makes the fuel/air mixture bum nearly simultaneously. There is no direct initiator of combustion. This makes the process inherently challenging to control. However, with advances in microprocessors and a physical understanding of the ignition process, HCCI can be controlled to achieve gasoline engine like emissions along with diesel engine like efficiency. In fact, HCCI engines have been shown to achieve extremely low levels of nitrogen oxide emissions (NOx) without treatment by catalytic converter. The unburned hydrocarbon and carbon monoxide emissions are still high due to lower peak temperatures, as in gasoline engines, and must still be treated to meet automotive emission regulations.
Refer to your maintenance suggestions for recommended service for the ignition system. The speed of the flame front is directly affected by compression ratio, fuel mixture temperature and octane or cetane rating of the fuel. Modern ignition systems are designed to ignite the mixture at the right time to ensure the flame front doesn’t contact the descending piston crown. If the flame front contacts the piston, pinking or knocking results. An engine that runs rough, bucks, surges, stalls, gets poor fuel economy or fails an emissions test are all signs of a potential ignition system problem. Although some cars now use platinum spark plugs with 100,000-mile service life, other parts such as ignition wires still need attention and periodic replacement. If your car exhibits any symptoms such as those mentioned here, be alert. If the glowing or light appears on the dashboard, you should have its cause investigated by a professional technician at your earliest opportunity. If the light flashes, the condition is more severe and must be checked out immediately to prevent damage to the catalytic converter.
Steering is the term applied to the collection of components and linkages which allow for a car to follow the desired course. The most conventional steering arrangement is to turn the front wheels using a hand-operated steering wheel which is positioned in front of the driver, via the steering column, which may contain universal joints to allow it to deviate somewhat from a straight line. You might be surprised to learn that when you turn your car, your front wheels are not pointing in the same direction. For a car to turn smoothly, each wheel must follow a different circle. Since the inside wheel is following a circle with a smaller radius, it is actually making a tighter turn than the outside wheel. If you draw a line perpendicular to each wheel, the lines will intersect at the center point of the turn. The geometry of the steering linkage makes the inside wheel turn more than the outside wheel. There are two most common types of steering gears: rack-and-pinion and recirculating ball-and-nut which is practically the same as worm-and-sector.
Many modern cars use rack and pinion steering mechanisms the major components of which constitute tie rod, steering arm and kingpin. When the steering wheel turns the pinion gear, the pinion moves the rack, which is a sort of linear gear which meshes with the pinion, from side to side. This motion applies steering torque to the kingpins of the steered wheels via tie rods and a short lever arm called the steering ann.
Older designs often use the recirculating ball mechanism, which is still found on trucks and utility vehicles. This is a variation of the worm-and- sector design, where the steering column turns a large screw (the ‘worm gear’) which meshes with a sector of a gear, causing it to rotate about its axis as the worm gear is turned; an arm attached to the axis of the sector moves the pitman arm, which is connected to the steering linkage and thus steers the wheels. The recirculating ball version of this apparatus reduces the considerable friction by placing large ball bearings between the teeth of the worm and those of the screw; at either end of the apparatus the balls exit from between the two pieces into a channel internal to the box which connects them with the other end of the apparatus, thus they are ‘recirculated’.
The rack and pinion design has the advantages of a large degree of feedback and direct steering ‘feel’, it also does not normally have any backlash, or slack. A disadvantage is that it is not adjustable, so that when it does wear and develop lash, the only cure is replacement.
The recirculating ball mechanism has the advantage of a much greater mechanical perfection, so that it was found on larger, heavier vehicles while the rack and pinion was originally limited to smaller and lighter ones. Due to the introduction of power steering, however, this is no longer an important advantage, leading to the increasing use of rack and pinion on newer cars. The recirculating ball design also has a perceptible lash, or ‘dead-spot’ on center, where a minute turn of the steering wheel in either direction does not move the steering apparatus; this is easily adjustable via a screw on the end of the steering box to account for wear, but it cannot be entirely eliminated or the mechanism begins to wear very rapidly.
This design is still in use in trucks and other large vehicles, where rapidity of steering and direct feel are less important than robustness, maintainability, and mechanical advantage. The much smaller degree of feedback with this design can also sometimes be an advantage; drivers of vehicles with rack and pinion steering can have their thumbs broken when a front wheel hits a bump, causing the steering wheel to kick to one side suddenly. These factors motivate the driving instructors telling students to keep their thumbs on the front of the steering wheel, rather than wrap around the inside of the rim. This effect is even stronger with a heavy vehicle like a truck; recirculating ball steering prevents this degree of feedback, just as it prevents desirable feedback under normal circumstances.
Various developments in steering systems like power steering, speed adjustable steering, four-wheel steering have appeared which are driven mostly by the need to increase the stability, safety and also the fuel efficiency of cars.
Cruise Control System
By Karim Nice
Cruise control is an invaluable feature on American cars. Without cruise control, long road trips would be more tiring, for the driver at least, and those of us suffering from lead-foot syndrome would probably get a lot more speeding tickets. Cruise control is far more common on American cars than European cars, because the roads in America are generally bigger and straighten, and destinations are farther apart. With traffic continually increasing, basic cruise control is becoming less useful, but instead of becoming obsolete, cruise control systems are adapting to this new reality — soon, cars will be equipped with adaptive cruise control, which will allow your car to follow the car in front of it while continually adjusting speed to maintain a safe distance.
What It Does? The cruise control system actually has a lot of functions other than controlling the speed of your car. For instance, the cruise control can accelerate or decelerate the car by 1 mph with the tap of a button. Hit the button five times to go 5 mph faster.
There are also several important safety features — the cruise control will disengage as soon as you hit the brake pedal, and it won’t engage at speeds less than 25 mph (40 kph). The system has five buttons: On, Off, Set/Accel, Resume and Coast. It also has a sixth control — the brake pedal, and if your car has a manual transmission the clutch pedal is also hooked up to the cruise control.
The on and off buttons don’t actually do much. Hitting the ‘on’ button does not do anything except telling the car that you might be hitting another button soon. The off button turns the cruise control off even if it is engaged. Some cruise controls don’t have these buttons; instead, they turn off when the driver hits the brakes, and turn on when the driver hits the set button.
The set/accel button tells the car to maintain the speed you are currently driving. If you bit the set button at 45 mph, the car will maintain your speed at 45 mph. Holding down the set/accel button will make the car accelerate; and on this car, tapping it once will make the car go 1 mph faster.
If you recently disengaged the cruise control by hitting the brake pedal, hitting the resume button will command the car to accelerate back to the most recent speed setting.
Holding down the coast button will cause the car to decelerate, just as if you took your foot completely off the gas. On this car, tapping the coast button once will cause the car to slow down by 1 mph.
The brake pedal and clutch pedal each have a switch that disengages the cruise control as soon as the pedal is pressed, so you can shut off the cruise control with a light tap on the brake or clutch.
How It’s Hooked Up. The cruise control system controls the speed of your car the same way you do — by adjusting the throttle position. But cruise control actuates the throttle valve by a cable connected to an actuator, instead of pressing a pedal. The throttle valve controls the power and speed of the engine by limiting how much air the engine takes in. Two cables connected to a pivot that moves the throttle valve. One cable comes from the accelerator pedal, and one from the actuator.
When the cruise control is engaged, the actuator moves the cable connected to the pivot, which adjusts the throttle; but it also pulls on the cable that is connected to the gas pedal - this is why your pedal moves up and down when the cruise control is engaged.
Many cars use actuators powered by engine vacuum to open and close the throttle. These systems use a small, electronically-controlled valve to regulate the vacuum in a diaphragm. This works in a similar way to the brake booster, which provides power to your brake system.
Controlling the Cruise Control. The brain of a cruise control system is a small computer that is normally found under the hood or behind the dashboard. It is connected to the throttle control, as well as several sensors. The diagram below shows the inputs and outputs of a typical cruise control system. A good cruise control system accelerates aggressively to the desired speed without overshooting, and then maintains that speed with little deviation no matter how much weight is in the car, or how steep the hill you drive up. Controlling the speed of a car is a classic application of control system theory. The cruise control system controls the speed of the car by adjusting the throttle position, so it needs sensors to tell it the speed and throttle position. It also needs to monitor the controls so it can tell what the desired speed is and when to disengage. The most important input is the speed signal; the cruise control system does a lot with this signal. First, let’s start with one of the most basic control systems you could have — a proportional control.
Proportional Control. In a proportional control system, the cruise control adjusts the throttle proportional to the error, the error being the difference between the desired speed and the actual speed. So, if the cruise control is set at 60 mph and the car is going 50 mph, the throttle position will be open quite far. When the car is going 55 mph, the throttle position opening will be only half of what it was before. The result is that the closer the car gets to the desired speed, the slower it accelerates. Also, if you were on a steep enough hill, the car might not accelerate at all.
PID Control. Most cruise control systems use a control scheme called PID control. Don’t worry, you don’t need to know any calculus to make it through this explanation — just remember that:
-The integral of speed is distance.
-The derivative of speed is acceleration.
A PID control system uses these three factors — proportional, integral and derivative, calculating each individually and adding them to get the throttle position.
We’ve already discussed the proportional factor. The integral factor is based on the time integral of the vehicle speed error. Translation: the difference between the distance your car actually travelled and the distance it would have travelled if it were going at the desired speed, calculated over a set period of time. This factor helps the car deal with hills, and also helps it settle into the correct speed and stay there. Det’s say your car starts to go up a hill and slows down. The proportional control increases the throttle a little, but you may still slow down. After a little while, the integral control will start to increase the throttle, opening it more and more, because the longer the car maintains a speed slower than the desired speed, the larger the distance error gets.
Now let’s add in the final factor, the derivative. Remember that the derivative of speed is acceleration. This factor helps the cruise control respond quickly to changes, such as hills. If the car starts to slow down, the cruise control can see this acceleration (slowing down and speeding up are both acceleration) before the speed can actually change much, and respond by increasing the throttle position.
A car Alarm is an electronic device installed in a vehicle in an attempt to discourage theft. Car alarms work by emitting high-volume sound (usually a siren, klaxon, pre-recorded verbal warning, the vehicle’s own horn, or a combination thereof) when triggered or when circuit is breached.
Car alarms can be designed to be triggered by vibrations, tilting of the car (to prevent unauthorized towing), touching the car, the opening or closing of special switches (e.g. door contacts), sensing small but rapid changes in battery voltage (which might indicate an interior light going on, or the ignition circuit being activated), or using volumetric sensors such as ultrasound, infrared or microwave.
Many times a car alarm can be triggered accidentally. This may be caused by the passing of large trucks, the vibration of thunder or people coming into contact with the vehicle, triggering the alarm sensors. Some sensors may need adjustment in order to prevent false alarms.
Because of the large number of false alarms with car alarms, many vehicle manufacturers no longer factory fit simple noise-making alarms, instead offering silent — but effective — immobilizers. Alternatively, an aftermarket vehicle tracking system can enable the police to trace stolen vehicles. Most police tracking systems require th
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