Transcript Slide 1
Uses:- 1) For traveling 2) For racing 3) For carrying goods PARTS OF CAR Engine Brake Steering Gear Box Silencer Radiator Bumpers Head lights Tail lights Tyre Mirror The basic components of an internal-combustion engine are the engine block, cylinder head, cylinders, pistons, valves, crankshaft, and camshaft. The lower part of the engine, called the engine block, houses the cylinders, pistons, and crankshaft. The components of other engine systems bolt or attach to the engine block. The block is manufactured with internal passageways for lubricants and coolant. Engine blocks are made of cast iron or aluminum alloy and formed with a set of round cylinders. The upper part of the engine is the cylinder head. Bolted to the top of the block, it seals the tops of the cylinders. Pistons compress air and fuel against the cylinder head prior to ignition. The top of the piston forms the floor of the combustion chamber. A rod connects the bottom of the piston to the crankshaft. Lubricated bearings enable both ends of the connecting rod to pivot, transferring the piston’s vertical motion into the crankshaft’s rotational force, or torque. The pistons’ motion rotates the crankshaft at speeds ranging from about 600 to thousands of revolutions per minute (rpm), depending on how much fuel is delivered to the cylinders. Fuel vapor enters and exhaust gases leave the combustion chamber through openings in the cylinder head controlled by valves. The typical engine valve is a metal shaft with a disk at one end fitted to block the opening. The other end of the shaft is mechanically linked to a camshaft, a round rod with odd-shaped lobes located inside the engine block or in the cylinder head. Inlet valves open to allow fuel to enter the combustion chambers. Outlet valves open to let exhaust gases out. A gear wheel, belt, or chain links the camshaft to the crankshaft. When the crankshaft forces the camshaft to turn, lobes on the camshaft cause valves to open and close at precise moments in the engine’s cycle. When fuel vapor ignites, the intake and outlet valves close tightly to direct the force of the explosion downward on the piston. Brakes enable the driver to slow or stop the moving vehicle. The first automobile brakes were much like those on horse-drawn wagons. By pulling a lever, the driver pressed a block of wood, leather, or metal, known as the shoe, against the wheel rims. With sufficient pressure, friction between the wheel and the brake shoe caused the vehicle to slow down or stop. Another method was to use a lever to clamp a strap or brake shoes tightly around the driveshaft. A brake system with shoes that pressed against the inside of a drum fitted to the wheel, called drum brakes, appeared in 1903. Since the drum and wheel rotate together, friction applied by the shoes inside the drum slowed or stopped the wheel. Cotton and leather shoe coverings, or linings, were replaced by asbestos after 1908, greatly extending the life of the brake mechanism. Hydraulically assisted braking was introduced in the 1920s. Disk brakes, in which friction pads clamp down on both sides of a disk attached to the axle, were in use by the 1950s. An antilock braking system (ABS) uses a computer, sensors, and a hydraulic pump to stop the automobile’s forward motion without locking the wheels and putting the vehicle into a skid. Introduced in the 1980s, ABS helps the driver maintain better control over the car during emergency stops and while braking on slippery surfaces. Automobiles are also equipped with a hand-operated brake used for emergencies and to securely park the car, especially on uneven terrain. Pulling on a lever or pushing down on a foot pedal sets the brake Automobiles are steered by turning the front wheels, although a few automobile types have all-wheel steering. Most steering systems link the front wheels together by means of a tie-rod. The tie-rod insures that the turning of one wheel is matched by a corresponding turn in the other. When a driver turns the steering wheel, the mechanical action rotates a steering shaft inside the steering column. Depending on the steering mechanism, gears or other devices convert the rotating motion of the steering wheel into a horizontal force that turns the wheels. Manual steering relies only on the force exerted by the driver to turn the wheels. Conventional power steering uses hydraulic pressure, operated by the pressure or movement of a liquid, to augment that force, requiring less effort by the driver. Electric power steering uses an electric motor instead of hydraulic pressure. The transmission, also known as the gearbox, transfers power from the engine to the driveshaft. As the engine’s crankshaft rotates, combinations of transmission gears pass the energy along to a driveshaft. The driveshaft causes axles to rotate and turn the wheels. By using gears of different sizes, a transmission alters the rotational speed and torque of the engine passed along to the driveshaft. Higher gears permit the car to travel faster, while low gears provide more power for starting a car from a standstill and for climbing hills. The transmission usually is located just behind the engine, although some automobiles were designed with a transmission mounted on the rear axle. There are three basic transmission types: manual, automatic, and continuously variable. A manual transmission has a gearbox from which the driver selects specific gears depending on road speed and engine load. Gears are selected with a shift lever located on the floor next to the driver or on the steering column. The driver presses on the clutch to disengage the transmission from the engine to permit a change of gears. The clutch disk attaches to the transmission’s input shaft. It presses against a circular plate attached to the engine’s flywheel. When the driver presses down on the clutch pedal to shift gears, a mechanical lever called a clutch fork and a device called a throwout bearing separate the two disks. Releasing the clutch pedal presses the two disks together, transferring torque from the engine to the transmission. An automatic transmission selects gears itself according to road conditions and the amount of load on the engine. Instead of a manual clutch, automatic transmissions use a hydraulic torque converter to transfer engine power to the transmission. Instead of making distinct changes from one gear to the next, a continuously variable transmission uses belts and pulleys to smoothly slide the gear ratio up or down. Continuously variable transmissions appeared on machinery during the 19th century and on a few smallengine automobiles as early as 1900. The transmission keeps the engine running at its most efficient speed by more precisely matching the gear ratio to the situation. Commercial applications have been limited to small engines The exhaust system carries exhaust gases from the engine’s combustion chamber to the atmosphere and reduces, or muffles, engine noise. Exhaust gases leave the engine in a pipe, traveling through a catalytic converter and a muffler before exiting through the tailpipe. Chemical reactions inside the catalytic converter change most of the hazardous hydrocarbons and carbon monoxide produced by the engine into water vapor and carbon dioxide. The conventional muffler is an enclosed metal tube packed with sound-deadening material. Most conventional mufflers are round or oval-shaped with an inlet and outlet pipe at either end. Some contain partitions to help reduce engine noise. Car manufacturers are experimenting with an electronic muffler, which uses sensors to monitor the sound waves of the exhaust noise. The sound wave data are sent to a computer that controls speakers near the tailpipe. The system generates sound waves 180 degrees out of phase with the engine noise. The sound waves from the electronic muffler collide with the exhaust sound waves and they cancel each other out, leaving only low-level heat to emerge from the tailpipe. Combustion inside an engine produces temperatures high enough to melt cast iron. A cooling system conducts this heat away from the engine’s coolant circulates through the engine. A pump cylinders and radiates it into the air. In most automobiles, a liquid sends the coolant from the engine to a radiator, which transfers heat from the coolant to the air. In early engines, the coolant was water. In most automobiles today, the coolant is a chemical solution called antifreeze that has a higher boiling point and lower freezing point than water, making it effective in temperature extremes. Some engines are air cooled, that is, they are designed so a flow of air can reach metal fins that conduct heat away from the cylinders. A second, smaller radiator is fitted to all modern cars. This unit uses engine heat to warm the interior of the passenger compartment and supply heat to the windshield defroster Manufacturers continue to build lighter vehicles with improved structural rigidity and ability to protect the driver and passengers during collisions. Bumpers evolved as rails or bars to protect the front and rear of the car’s body from damage in minor collisions. Over the years, bumpers became stylish and, in some cases, not strong enough to survive minor collisions without expensive repairs. Eventually, government regulations required bumpers designed to withstand low-speed collisions with less damage. Some bumpers can withstand 4-km/h (2.5-mph) collisions with no damage, while others can withstand 8-km/h (5-mph) collisions with no damage Headlights are mounted on the front of the car to light the road ahead during night or foggy days. They have reflectors and special lenses and are usually the sealed beam construction type, with the filament, reflector and lens fused together into an airtight unit. The most popular type of headlight is the halogen type, because it provides bright illumination. The halogen bulb is filled with pressurized gas (halogen) and can produce flying fragments if shattered. Wear protective glasses for changing a halogen lamp and always throw out the old one in the protective carton that comes with the new one. Auto lights are very important because they enhance visibility on the road and keep the driver and passengers safe especially in driving through poorly lit areas. Wheels support the vehicle’s weight and transfer torque to the tires from the drivetrain and braking systems. Automobile wheels generally are made of steel or aluminum. Aluminum wheels are lighter, more impact absorbent, and more expensive. Pneumatic (air-filled) rubber tires, first patented in 1845, fit on the outside rims of the wheels. Tires help smooth out the ride and provide the automobile’s only contact with the road, so traction and strength are primary requirements. Tire treads come in several varieties to match driving conditions To see the vehicles behind the car The history of the automobile actually began about 4,000 years ago when the first wheel was used for transportation in India. In the early 15th century the Portuguese arrived in China and the interaction of the two cultures led to a variety of new technologies, including the creation of a wheel that turned under its own power. By the 1600s small steam-powered engine models had been developed, but it was another century before a full-sized engine-powered vehicle was created. In 1769 French Army officer Captain Nicolas-Joseph Cugnot built what has been called the first automobile. Cugnot’s three-wheeled, steam-powered vehicle carried four persons. Designed to move artillery pieces, it had a top speed of a little more than 3.2 km/h (2 mph) and had to stop every 20 minutes to build up a fresh head of steam. As early as 1801 successful but very heavy steam automobiles were introduced in England. Laws barred them from public roads and forced their owners to run them like trains on private tracks. In 1802 a steam-powered coach designed by British engineer Richard Trevithick journeyed more than 160 km (100 mi) from Cornwall to London. Steam power caught the attention of other vehicle builders. In 1804 American inventor Oliver Evans built a steam-powered vehicle in Chicago, Illinois. French engineer Onésiphore Pecqueur built one in 1828. British inventor Walter Handcock built a series of steam carriages in the mid-1830s that were used for the first omnibus service in London. By the mid-1800s England had an extensive network of steam coach lines. Horse-drawn stagecoach companies and the new railroad companies pressured the British Parliament to approve heavy tolls on steam-powered road vehicles. The tolls quickly drove the steam coach operators out of business. During the early 20th century steam cars were popular in the United States. Most famous was the Stanley Steamer, built by American twin brothers Freelan and Francis Stanley. A Stanley Steamer established a world land speed record in 1906 of 205.44 km/h (121.573 mph). Manufacturers produced about 125 models of steam-powered automobiles, including the Stanley, until 1932. 1) 3) 2) ABHIJITH.S HARIKRISHNAN.D PRANOY.P SREEJITHKRISHNAN.R www.maruthi.com www.autocarsindia.com www.ferrari.com CERTIFICATE This is to certify that this project is done by themselves during their training period from 30-11-2005 to 21-12-2005 at S.M.V.G.M.H.S.S.