Tech@Edu

Body "Body is nothing but the 'face structure' of the automobile. Body is only aspect to provide ergonomics feature in any automobile." It consist of doors, windows, side panels, fenders, front & rear bumpers, grille, pillar etc. A body sometimes referred to as "coachwork". The body is that part where passengers have occupies their seats or the luggage and other placed cargo to be carried.  Body is built on the chassis to complete the vehicle. Chassis & body makes the complete automobile vehicle. For small & light car, body & chassis are made as a single unit but in large vehicles both are made as a single unit. Generally body surface is made from metal or fiber. The body is usually made from a large number of steel pressings which are welded together.  The body is bolted to the chassis at numerous points. The rubber or felt-strips being interposed to damp-down (reduce) the vibrations and noise.  Main purpose of the body is to provide safety

Fuel Atomizer or Injector “Fuel injector is an electronically controlled mechanical device that is responsible for spraying (injecting) the right amount of fuel into the engine so that a suitable air/fuel mixture is created for optimal combustion.”  Types of Fuel Injector 1. Single-point or throttle body injection 2. Port or multi-point fuel injection 3. Sequential fuel injection 4. Direct injection 1. Single-point or throttle body injection The throttle body injection (TBI) system is one of the first types of injection systems ever used by vehicles. Before TBI, vehicles used a carburetor. TBIs work in a manner very similar to a carburetor. The fuel is still sucked into the cylinders because of the suction created by the engine. However, TBIs are controlled by an electronic computer within the vehicle. The computer provides more accuracy by determining the amount of fuel that should be deposited into the engine. This accuracy ensures less fuel is wasted and allows the vehicle to run mo

FUEL PUMP “A fuel pump is a device which deliver the fuel inside the fuel atomizer or fuel injector.” The purpose of the fuel pump is to meter the correct quantity of fuel and deliver it at the correct time to the engine cylinder according to the varying load and speed requirements. Parts of Fuel Pump The Fuel pump consists of following parts. 1. Plunger 2. Barrel 3. Delivery Valve 4. Ports 5. Spring 6. Rack Construction of Fuel Pump Its consists of Plunger which is driven by the cam & tappet mechanism, Barrel in which plunger reciprocate, Delivery Valve which lift off its seat under the liquid fuel pressure & spring force. The fuel pump is connected to the fuel injector through the passage P. SP & Y are the spill & supply port respectively. Types of Fuel Pump Two general types of fuel pump are as follows: 1. Mechanical Fuel Pump 2. Electrical Fuel Pump 1.  Mechanical Fuel Pump The mechanical fuel pump is operated by an eccentric on the engine camshaft. It is mounted o

Fuel Supply System “The fuel system of an internal combustion Engine is intended to produce a combustible mixture, composed of the fuel stored in the fuel tank and atmospheric air, and then deliver both to the cylinders.” Fuel Injection for SI Engine In a S.I engine, a measured quantity of petrol or gas is already mixed with air in a calculated proportion before being sucked by engine. Then this combustible charge having right quantity of fuel-air is ignited at the appropriate time at the end of compression stroke in the engine with the help of a spark plug. Depending on the method of mixing petrol or gas in the air in right proportion as per the requirement of engine, the fuel supply system of S.I engine is conventionally is of two types. 1. Carburetion In the carburetion method, fuel stored in the fuel tank is supplied to carburetor by means of a simple diaphragm pump through a fuel filter. The job of pump is only to supply fuel from fuel tank to float chamber of carburetor. Sometime

Wheel & Tyre Assembly Wheel “The wheel assembly consists of the hub, disc or spokes, rim, tyre & tube.”  Wheels is the important part of the vehicle. The vehicle can’t move on the road without wheels. “The wheels are legs of the vehicle carry it to far off distance. The support of the whole weight of the vehicle & convert rotary motion into longitudinal one.” The wheel also resists side force created by turning also absorb the road shocks. Essential  Requirement of Wheel In an automobile essential requirement of wheels are as follows–  1. Strong enough to take the weight of vehicle.  2. Flexible to absorb the road shocks.  3. Perfectly balanced statically as well as dynamically.  4. Able to grip the road surface.  5. Mounted or remove easily.  6. Not too expensive.  7. Lightest possible so that the unsprang weight is least. Classification of Wheel The automobile wheels are generally three types:-  (i) Pressed steel disc wheels.  (ii) Wire wheels.  (iii) Light alloy cas