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Tài liệu học tập cơ bản khái quát về động cơ và các bộ phận trên ô tô phiên bản tiếng anh. Tài liệu này nhằm giúp chúng ta tiếp cận được cấu tạo chức năng của các bộ phận của xe. Với tài liệu này giúp các bạn sinh viên ngành cơ khí ô tô tiếp cận được những kiến thức cơ bản về ô tô và đồng thời nâng cao kiến thức tiếng anh. Bộ tài liệu này được soạn thảo bởi trường đào tạo và huấn luyện nghề ở Canada.
Chapter Automotive Systems Automotive History • Early vehicles were powered by electricity or steam • Most bodies were open carriage designs • Few major changes from the 1930s until the 1960s • Improved safety and pollution controls in the 1960s 1970s • OPEC oil embargo created fuel shortages and the demand for smaller, more efficient vehicles • The Corporate Average Fuel Economy (CAFE) standard set in 1975 • Leaded fuel phased out • Catalytic converters introduced 1980s • Mechanical systems replaced by electronic components • First use of electronic engine controls • Anti-Lock brakes introduced • Passive restraint systems and air bags installed • Fuel injection replacing carburetion 1990s • Fuel injection standard on all engines • Increasing use of electronics and computers • Passive restraints and ABS standard equipment on new cars • First hybrid vehicles appear 2000s • Electronics and computer systems manage most on-board vehicle functions • GPS, navigation, adaptive cruise control, and dynamic vehicle control systems standard equipment • Hybrids available from several manufacturers Typical Body Over Frame A Unibody Design The Basic Engine • Gasoline engines most common in passenger cars • Uses a spark ignition system • Combined with electric motors in hybrid vehicles • Diesel engines most common in heavy duty applications • Uses compression pressure for ignition • Newer diesels much cleaner and quieter Cylinder Block • Made from cast iron or aluminum • Contains the crankshaft, pistons, and connecting rods • Forms the lower half of the engine Cylinder Head • Mounts on top of engine block • Made of cast iron or aluminum • Contains camshaft and valves • Has intake and exhaust manifolds attached Engine Systems • • • • Lubrication system Cooling system Fuel and air system Emission control system • Exhaust system • Ignition system • Starting and charging system • Electronic engine control system • On-board diagnostics Lubrication System • Supplies clean oil to various parts of the engine • Removes heat from combustion • Removes combustion by-products • Filters oil Cooling System • Removes heat from combustion • Maintains proper engine operating temperature • Supplies heat for passenger compartment Fuel and Air Systems • Fuel system stores and supplies fuel to the engine • Contains fuel tank, pump, and filter • Fuel is injected into engine by fuel injectors • Air intake system supplies filtered air to the engine • Air is drawn into the cylinder and mixed with fuel for combustion Ignition System • Must ignite the air/fuel mixture a precisely the correct time • Boosts battery voltage to 20,000 – 40,000 volts • Changes spark timing based on engine load, speed, and other factors Starting and Charging Systems • Electric motor converts stored energy into motion • Generator converts movement into electrical energy • Starter motors and generators can be conventional 12v or part of hybrid motor/generator assembly Heating System • Uses coolant heated by the engine to warm the passenger compartment • Thermostat maintains minimum system temperature Air Conditioning • The A/C system removes heat and moisture from the passenger compartment • The A/C compressor can be belt driven or electric on a hybrid vehicle Hybrid Electric Vehicles (HEVs) • HEVs use one or more electric motors and an internal combustion engine (ICE) to propel the vehicle • HEVs recapture braking energy to recharge the high-voltage batteries • The high-voltage batteries pose a significant safety hazard if proper precautions are not followed ... introduced 1980s • Mechanical systems replaced by electronic components • First use of electronic engine controls • Anti-Lock brakes introduced • Passive restraint systems and air bags installed... appear 2000s • Electronics and computer systems manage most on-board vehicle functions • GPS, navigation, adaptive cruise control, and dynamic vehicle control systems standard equipment • Hybrids.. .Automotive History • Early vehicles were powered by electricity or steam • Most bodies were open