A beam axle, rigid axle or solid axle is a dependent suspension design, in which a set of wheels is connected laterally by a single beam or shaft. Beam axles were once used at the rear wheels of a vehicle, but they have been used as front axles in rear-wheel-drive vehicles. In most automobiles, beam axles have been replaced by front and rear independent suspensions. With a beam axle the camber angle between the wheels is the same no matter where it is in the travel of the suspension. A beam axle's fore & aft location is constrained by either: trailing arms, semi-trailing arms, radius rods, or leaf springs; the lateral location can be constrained by a Panhard rod, a Scott Russell linkage or a Watt's linkage, or some other arrangement, most by the leaf springs. Shock absorbers and either leaf springs, coil springs, or air bags are used to control vertical movement; the Twist-beam rear suspension is a similar suspension design, however its beam axle is able to twist thereby functioning as an anti-roll bar to control the roll motion of the body and is considered to be a semi-independent suspension design.
A live axle is a type of beam axle in which the shaft transmits power to the wheels. While used in vehicles with Hotchkiss drive, this suspension system can be used with other types of power transmission; the principal advantage of the beam axle is its simplicity. This simplicity makes it space-efficient and cheap to manufacture, they are nearly universally used in heavy-duty trucks. Most light and medium duty pickup trucks, SUVs, vans use a beam axle, at least in the rear. Beam axles have an important advantage for off-road applications, as they provide better vehicle articulation and durability in a high load environment; the drawbacks are that it does not allow each wheel to move independently in response to bumps, the mass of the beam is part of the unsprung weight of the vehicle, which can further reduce ride quality. The cornering ability is worse than other suspension designs because the wheels have zero camber angle gain during body roll. Front beam axle suspension is unusually sensitive to any lack of concentricity in the hub and wheel assembly which can cause a side-to-side oscillation of the steering at certain speeds.
This is addressed on some vehicles with steering dampers although removal and careful refitting of the front wheels cures the problem. Axle Twist-beam rear suspension
A gear train is a mechanical system formed by mounting gears on a frame so the teeth of the gears engage. Gear teeth are designed to ensure the pitch circles of engaging gears roll on each other without slipping, providing a smooth transmission of rotation from one gear to the next; the transmission of rotation between contacting toothed wheels can be traced back to the Antikythera mechanism of Greece and the south-pointing chariot of China. Illustrations by the Renaissance scientist Georgius Agricola show gear trains with cylindrical teeth; the implementation of the involute tooth yielded a standard gear design that provides a constant speed ratio. Features of gears and gear trains include: The ratio of the pitch circles of mating gears defines the speed ratio and the mechanical advantage of the gear set. A planetary gear train provides high gear reduction in a compact package, it is possible to design gear teeth for gears that are non-circular, yet still transmit torque smoothly. The speed ratios of chain and belt drives are computed in the same way as gear ratios.
See bicycle gearing. Gear teeth are designed so the number of teeth on a gear is proportional to the radius of its pitch circle, so the pitch circles of meshing gears roll on each other without slipping; the speed ratio for a pair of meshing gears can be computed from ratio of the radii of the pitch circles and the ratio of the number of teeth on each gear. The velocity v of the point of contact on the pitch circles is the same on both gears, is given by v = r A ω A = r B ω B, where input gear A with radius rA and angular velocity ωA meshes with output gear B with radius rB and angular velocity ωB. Therefore, ω A ω B = r B r A = N B N A. where NA is the number of teeth on the input gear and NB is the number of teeth on the output gear. The mechanical advantage of a pair of meshing gears for which the input gear has NA teeth and the output gear has NB teeth is given by M A = N B N A; this shows that if the output gear GB has more teeth than the input gear GA the gear train amplifies the input torque.
And, if the output gear has fewer teeth than the input gear the gear train reduces the input torque. If the output gear of a gear train rotates more than the input gear the gear train is called a speed reducer. In this case, because the output gear must have more teeth than the input gear, the speed reducer amplifies the input torque. For this analysis, we consider a gear train that has one degree-of-freedom, which means the angular rotation of all the gears in the gear train are defined by the angle of the input gear; the size of the gears and the sequence in which they engage define the ratio of the angular velocity ωA of the input gear to the angular velocity ωB of the output gear, known as the speed ratio, or gear ratio, of the gear train. Let R be the speed ratio ω A ω B = R; the input torque TA acting on the input gear GA is transformed by the gear train into the output torque TB exerted by the output gear GB. If we assume the gears are rigid and there are no losses in the engagement of the gear teeth the principle of virtual work can be used to analyze the static equilibrium of the gear train.
Let the angle θ of the input gear be the generalized coordinate of the gear train the speed ratio R of the gear train defines the angular velocity of the output gear in terms of the input gear: ω A = ω, ω B = ω / R. The formula for the generalized force obtained from the principle of virtual work with applied torques yields: F θ = T A ∂ ω A ∂ ω − T B ∂ ω B ∂ ω = T A − T B / R = 0; the mechanical advantage of the gear train is the ratio of the output torque TB to the input torque TA, the above equation yields: M A = T B T A = R. The speed ratio of a gear train defines its mechanical advantage; this shows that if the input gear rotates faster than the output gear the gear train amplifies the input torque. And if the input gear rotates slower than the output gear, the gear train reduces the input torque; the simplest example of a gear train has two gears. The "input gear" transmits power to the "output gear"; the input gear will be connected to a power source, such as a motor or engine. In such a
Italy the Italian Republic, is a country in Southern Europe. Located in the middle of the Mediterranean Sea, Italy shares open land borders with France, Austria and the enclaved microstates San Marino and Vatican City. Italy covers an area of 301,340 km2 and has a temperate seasonal and Mediterranean climate. With around 61 million inhabitants, it is the fourth-most populous EU member state and the most populous country in Southern Europe. Due to its central geographic location in Southern Europe and the Mediterranean, Italy has been home to a myriad of peoples and cultures. In addition to the various ancient peoples dispersed throughout modern-day Italy, the most famous of which being the Indo-European Italics who gave the peninsula its name, beginning from the classical era and Carthaginians founded colonies in insular Italy and Genoa, Greeks established settlements in the so-called Magna Graecia, while Etruscans and Celts inhabited central and northern Italy respectively; the Italic tribe known as the Latins formed the Roman Kingdom in the 8th century BC, which became a republic with a government of the Senate and the People.
The Roman Republic conquered and assimilated its neighbours on the peninsula, in some cases through the establishment of federations, the Republic expanded and conquered parts of Europe, North Africa and the Middle East. By the first century BC, the Roman Empire emerged as the dominant power in the Mediterranean Basin and became the leading cultural and religious centre of Western civilisation, inaugurating the Pax Romana, a period of more than 200 years during which Italy's technology, economy and literature flourished. Italy remained the metropole of the Roman Empire; the legacy of the Roman Empire endured its fall and can be observed in the global distribution of culture, governments and the Latin script. During the Early Middle Ages, Italy endured sociopolitical collapse and barbarian invasions, but by the 11th century, numerous rival city-states and maritime republics in the northern and central regions of Italy, rose to great prosperity through shipping and banking, laying the groundwork for modern capitalism.
These independent statelets served as Europe's main trading hubs with Asia and the Near East enjoying a greater degree of democracy than the larger feudal monarchies that were consolidating throughout Europe. The Renaissance began in Italy and spread to the rest of Europe, bringing a renewed interest in humanism, science and art. Italian culture flourished, producing famous scholars and polymaths such as Michelangelo, Leonardo da Vinci, Raphael and Machiavelli. During the Middle Ages, Italian explorers such as Marco Polo, Christopher Columbus, Amerigo Vespucci, John Cabot and Giovanni da Verrazzano discovered new routes to the Far East and the New World, helping to usher in the European Age of Discovery. Italy's commercial and political power waned with the opening of trade routes that bypassed the Mediterranean. Centuries of infighting between the Italian city-states, such as the Italian Wars of the 15th and 16th centuries, left the region fragmented, it was subsequently conquered and further divided by European powers such as France and Austria.
By the mid-19th century, rising Italian nationalism and calls for independence from foreign control led to a period of revolutionary political upheaval. After centuries of foreign domination and political division, Italy was entirely unified in 1871, establishing the Kingdom of Italy as a great power. From the late 19th century to the early 20th century, Italy industrialised, namely in the north, acquired a colonial empire, while the south remained impoverished and excluded from industrialisation, fuelling a large and influential diaspora. Despite being one of the main victors in World War I, Italy entered a period of economic crisis and social turmoil, leading to the rise of a fascist dictatorship in 1922. Participation in World War II on the Axis side ended in military defeat, economic destruction and the Italian Civil War. Following the liberation of Italy and the rise of the resistance, the country abolished the monarchy, reinstated democracy, enjoyed a prolonged economic boom and, despite periods of sociopolitical turmoil became a developed country.
Today, Italy is considered to be one of the world's most culturally and economically advanced countries, with the sixth-largest worldwide national wealth. Its advanced economy ranks eighth-largest in the world and third in the Eurozone by nominal GDP. Italy owns the third-largest central bank gold reserve, it has a high level of human development, it stands among the top countries for life expectancy. The country plays a prominent role in regional and global economic, military and diplomatic affairs. Italy is a founding and leading member of the European Union and a member of numerous international institutions, including the UN, NATO, the OECD, the OSCE, the WTO, the G7, the G20, the Union for the Mediterranean, the Council of Europe, Uniting for Consensus, the Schengen Area and many more; as a reflection
The torpedo body style was a type of automobile body used from 1908 until the mid-1930s which had a streamlined profile and a folding or detachable soft top. The design consists of a hood/bonnet line raised to be level with the car's waistline, resulting in a straight beltline from front to back; the name was introduced in 1908 when Captain Theo Masui, the London-based importer of French Gregoire cars, designed a streamlined body and called it "The Torpedo". The Torpedo body style was fitted to 4- or 5-seat touring cars with detachable or folding roof, low side panels and doors. Torpedo cars didn't have B pillars, so the only uprights present were those supporting the windshield. Similar styles are baquet; the name is used for trucks with a hood/bonnet
Front-engine, rear-wheel-drive layout
In automotive design, an FR, or front-engine, rear-wheel-drive layout is one where the engine is located at the front of the vehicle and driven wheels are located at the rear. This was the traditional automobile layout for most of the 20th century. Modern designs use the front-engine, front-wheel-drive layout. In automotive design, a front mid-engine, rear-wheel-drive layout is one that places the engine in the front, with the rear wheels of vehicle being driven. In contrast to the front-engine, rear-wheel-drive layout, the engine is pushed back far enough that its center of mass is to the rear of the front axle; this aids in weight distribution and reduces the moment of inertia, improving the vehicle's handling. The mechanical layout of an FMR is the same as an FR car; some models of the same vehicle can be classified as either FR or FMR depending on the length of the installed engine and its centre of mass in relation to the front axle. FMR cars are characterized by a long hood and front wheels that are pushed forward to the corners of the vehicle, close to the front bumper.
Grand tourers have FMR layouts, as a rear engine would not leave much space for the rear seats. FMR should not be confused with a "front midships" location of the engine, referring to the engine being located behind the front axle centerline, in which case a car meeting the above FMR center of mass definition could be classified as a FR layout instead; the v35 Nissan Skyline / Infiniti G35 / Nissan 350Z are FM cars. FMR layout came standard in most pre–World War II, front-engine / rear-wheel-drive cars
The Targa Florio was an open road endurance automobile race held in the mountains of Sicily near the island's capital of Palermo. Founded in 1906, it was the oldest sports car racing event, part of the World Sportscar Championship between 1955 and 1973. While the first races consisted of a whole tour of the island, the track length in the race's last decades was limited to the 72 kilometres of the Circuito Piccolo delle Madonie, lapped 11 times. After 1973, it was a national sports car event until it was discontinued in 1977 due to safety concerns, it has since been run as a rallying event, is part of the Italian Rally Championship. The race was created in 1906 by the wealthy pioneer race driver and automobile enthusiast, Vincenzo Florio, who had started the Coppa Florio race in Brescia, Lombardy in 1900; the Targa claimed to be a worldly event not to be missed. Renowned artists, such as Alexandre Charpentier and Leonardo Bistolfi, were commissioned to design medals. A magazine was initiated, which aimed to enhance, with graphic and photographic reproductions of the race, the myth of the car and the typical character of modern life, speed.
One of the toughest competitions in Europe, the first Targa Florio covered 3 laps equalling 277 miles through multiple hairpin curves on treacherous mountain roads, at heights where severe changes in climate occurred. Alessandro Cagno won the inaugural 1906 race in nine hours. By the mid-1920s, the Targa Florio had become one of Europe's most important races, as neither the 24 Hours of Le Mans nor the Mille Miglia had been established yet. Grand Prix races were still isolated events, not a series like today's F1; the wins of Mercedes in the 1920s made a big impression in Germany that of German Christian Werner in 1924, as he was the first non-Italian winner since 1920. Rudolf Caracciola repeated. In 1926, Eliska Junkova, one of the great female drivers in Grand Prix motor racing history, became the first woman to compete in the race. In 1953, the FIA World Sportscar Championship was introduced; the Targa became part of it in 1955, when Mercedes had to win 1-2 with the Mercedes-Benz 300 SLR in order to beat Ferrari for the title.
They had missed the first two of the 6 events, Buenos Aires and the 12 Hours of Sebring, where Ferrari, Jaguar and Porsche scored. Mercedes appeared at and won in the Mille Miglia pulled out of Le Mans as a sign of respect for the victims of the 1955 Le Mans disaster, but won the Tourist Trophy at Dundrod. Stirling Moss/Peter Collins and Juan Manuel Fangio/Karl Kling finished minutes ahead of the best Ferrari and secured the title. Several versions of the track were used, it started with a single lap of a 148 km circuit from 1906-1911 and 1931. From 1912 to 1914 a tour around the perimeter of Sicily was used, with a single lap of 975 kilometres, lengthened to 1,080 kilometres from 1948 to 1950; the 148 km "Grande" circuit was shortened twice, the first time to 108 km, the version used from 1919-1930, to the 72 km circuit used from 1932 to 1936 and 1951 to 1977. From 1951-1958, the long coastal island tour variant was used for a separate event called the Giro di Sicilia; the start and finish took place at Cerda.
The counter-clockwise lap lead from Caltavuturo and Collesano from an altitude over 600 metres down to sea level, where the cars raced from Campofelice di Roccella on the Buonfornello straight along the coast, a straight over 6 km longer than the Mulsanne Straight at the Circuit de la Sarthe in Le Mans. The longest version of the circuit went south through Caltavuturo through an extended route through elevation changes, swept through the nearby towns of Castellana and Sottana, twisting around mountains up to the town of Castelbuono and rejoined the most recent version of the track at Collesano; the second version of the track went south through Caltavuturo and took a shortcut starting right before Castellana to Collesano via the town of Polizzi Generosa. There was a closed circuit called Favorita Park used from 1937-1940; the challenge of the Targa was unprecedented in its difficulty and the driving experience of any of the course variants was unlike any other circuit in the world other than that of the Nurburgring in Germany.
The original Grande 148 km circuit had in the realm of 2,000 corners per lap, the 108 km Medio had about 1,300-1,400 corners per lap and the final iteration of the course, the 72 km Piccolo circuit had about 800-900 corners per lap. To put that in perspective, most purpose built circuits have between 12 and 18 corners, the longest purpose built circuit in the world, the 13-mile Nurburgring, has about 180 corners. So learning any of the Targa Florio courses was difficult and required, like most long circuits, at least 60 laps to learn the course- and unlike the purpose-built Nurburgring, the course had to be learned properly in public traffic, one lap would take about an hour to do in a road car- if there was little to no traffic. Like a rally event, the race cars were started one by one every 15 seconds for a time trial, as a start from a full grid was not possible on the tight and twisty roads. Although the public road circuit used for the Targa was challenging- it was a different kind of circuit and race from any other race on the sportscar calendar.
All of the circuit variations of the Targa had so many corners that lap speeds at the Targa n
An engine or motor is a machine designed to convert one form of energy into mechanical energy. Heat engines, like the internal combustion engine, burn a fuel to create heat, used to do work. Electric motors convert electrical energy into mechanical motion, pneumatic motors use compressed air, clockwork motors in wind-up toys use elastic energy. In biological systems, molecular motors, like myosins in muscles, use chemical energy to create forces and motion; the word engine derives from Old French engin, from the Latin ingenium–the root of the word ingenious. Pre-industrial weapons of war, such as catapults and battering rams, were called siege engines, knowledge of how to construct them was treated as a military secret; the word gin, as in cotton gin, is short for engine. Most mechanical devices invented during the industrial revolution were described as engines—the steam engine being a notable example. However, the original steam engines, such as those by Thomas Savery, were not mechanical engines but pumps.
In this manner, a fire engine in its original form was a water pump, with the engine being transported to the fire by horses. In modern usage, the term engine describes devices, like steam engines and internal combustion engines, that burn or otherwise consume fuel to perform mechanical work by exerting a torque or linear force. Devices converting heat energy into motion are referred to as engines. Examples of engines which exert a torque include the familiar automobile gasoline and diesel engines, as well as turboshafts. Examples of engines which produce thrust include rockets; when the internal combustion engine was invented, the term motor was used to distinguish it from the steam engine—which was in wide use at the time, powering locomotives and other vehicles such as steam rollers. The term motor derives from the Latin verb moto which means to maintain motion, thus a motor is a device. Motor and engine are interchangeable in standard English. In some engineering jargons, the two words have different meanings, in which engine is a device that burns or otherwise consumes fuel, changing its chemical composition, a motor is a device driven by electricity, air, or hydraulic pressure, which does not change the chemical composition of its energy source.
However, rocketry uses the term rocket motor though they consume fuel. A heat engine may serve as a prime mover—a component that transforms the flow or changes in pressure of a fluid into mechanical energy. An automobile powered by an internal combustion engine may make use of various motors and pumps, but all such devices derive their power from the engine. Another way of looking at it is that a motor receives power from an external source, converts it into mechanical energy, while an engine creates power from pressure. Simple machines, such as the club and oar, are prehistoric. More complex engines using human power, animal power, water power, wind power and steam power date back to antiquity. Human power was focused by the use of simple engines, such as the capstan, windlass or treadmill, with ropes and block and tackle arrangements; these were used in cranes and aboard ships in Ancient Greece, as well as in mines, water pumps and siege engines in Ancient Rome. The writers of those times, including Vitruvius and Pliny the Elder, treat these engines as commonplace, so their invention may be more ancient.
By the 1st century AD, cattle and horses were used in mills, driving machines similar to those powered by humans in earlier times. According to Strabo, a water powered mill was built in Kaberia of the kingdom of Mithridates during the 1st century BC. Use of water wheels in mills spread throughout the Roman Empire over the next few centuries; some were quite complex, with aqueducts and sluices to maintain and channel the water, along with systems of gears, or toothed-wheels made of wood and metal to regulate the speed of rotation. More sophisticated small devices, such as the Antikythera Mechanism used complex trains of gears and dials to act as calendars or predict astronomical events. In a poem by Ausonius in the 4th century AD, he mentions a stone-cutting saw powered by water. Hero of Alexandria is credited with many such wind and steam powered machines in the 1st century AD, including the Aeolipile and the vending machine these machines were associated with worship, such as animated altars and automated temple doors.
Medieval Muslim engineers employed gears in mills and water-raising machines, used dams as a source of water power to provide additional power to watermills and water-raising machines. In the medieval Islamic world, such advances made it possible to mechanize many industrial tasks carried out by manual labour. In 1206, al-Jazari employed a crank-conrod system for two of his water-raising machines. A rudimentary steam turbine device was described by Taqi al-Din in 1551 and by Giovanni Branca in 1629. In the 13th century, the solid rocket motor was invented in China. Driven by gunpowder, this simplest form of internal combustion engine was unable to deliver sustained power, but was useful for propelling weaponry at high speeds towards enemies in battle and for fireworks. After invention, this innovation spread throughout Europe; the Watt steam engine was the first type of steam engine to make use of steam at a pressure just above atmospheric to drive the piston he