Power transmission in Automobiles

Power transmission in Automobiles

1. POWER TRANSMISSION (in automobiles)

2. Two wheel drive (FROM ENGINE TO REAR WHEELS POWER TRANSMISSION)

3. What is Transmission? The mechanism that transmits the power developed by the engine of automobile to the engine to the driving wheels( rear wheels ) is called the TRANSMISSION and the system is called TRANSMISSION SYSTEM . It is used to transmit engine torque to the driving wheels to drive the vehicle on the road. .

4. Provide means of connection and disconnection of engine with rest of power train without shock and smoothly. Enable power transmission at varied angles and varied lengths. Provide means to drive the driving wheels at different speeds when required. Provide a varied leverage between the engine and the drive wheels Why do we need Transmission System ?

5. Parts of a transmission system ENGINE FLYWHEEL CLUTCH GEAR BOX (or) TRANSMISSION BOX UNIVERSAL JOINT PROPELLER SHAFT OR DRIVE SHAFT DIFFERENTIAL REAR WHEEL AXLE REAR WHEELS

6. ENGINE Engine is a mechanical device which converts the chemical energy of a fuel into heat or thermal energy and then converts the heat energy into mechanical energy and makes the vehicle to run at different loads. Engines are again classified into IC or EC Engines and are used for different purposes. So the main purpose of engine is to transfer mechanical energy to different parts of the transmission system by the crankshaft.

7. FLYWHEEL A FLYWHEEL is connected to the crankshaft of the engine which is a rotating device. FLYWHEEL is a body having large mass and it act as a reservoir for energy store coming from the engine. It stores energy from engine when it is more and releases the energy when it is more than requirement. In IC engines power produced in one stroke and the remaining three strokes are idle. So in that case a Flywheel supplies energy to all the rotating parts and makes the crankshaft to run at uniform speeds.

8. CLUTCH The purpose of clutch is to engage and disengage the transmission system from the engine when a vehicle is being driven away from a standstill and when the gearbox gear change is necessary. The gradual increase in the transfer of engine torque to the transmissions roust be smooth. When the clutch is in the coupling (normal running) position, power fl ows through it from the engine to the transmission. If the transmission is in gear, then power flows on through to the propelling wheels of the vehicle. The cl utch contains a friction disc, spring arrangement and pressure plate for pressing this disc tightly against the smooth rear face of the flywheel.  

9. GEAR BOX This GEAR BOX is considered as the heart of the transmission system. • It is located between Clutch and Propeller shaft . • Gear box varies the leverage (speed ratio & hence torque ratio) between the engine &driving wheels. • It is provided with either 4 speed or 5 speed ratios or more depending on design. to change the gears to travel at different speeds.  

10. UNIVERSAL JOINT A UNIVERSAL JOINT is used to transmit power from gear box to PROPELLER SHAFT. And then from PROPELLER SHAFT to DIFFRENTIAL. So to maintain uniform speed and mation,two universal joints are used, one b/w gear box and drive shaft and anoher b/w drive shaft and differential and the coupling is called universal coupling. They are designed to to eliminate torque and speed fluctions (for constant velocity)   If only one universal joint isused , speed fluctuations will not be neutralized

11. PROPELLER SHAFT Front engine rear wheel drive Reduction in car height (lowering of body). It propels the vehicle forward, so called propeller shaft. A Propeller Shaft connects a gearbox to a Differential. It is used to transmit the drive force generated by the engine to the axles. It is provided with two U-joints to maintain constant velocity and positioning of differential at different plane. It is provided with a slip joint to take care of the change inlength . It is strong enough to handle maximum low gear torque.      

12. DIFFERENTIAL To transfer the engine power to the rear wheels. To act as the final gear reduction in the vehicle. To make the wheels to rotate at different speeds neglecting the turn. It is provided with different gears to transmit power to rear wheels.        

13. REAR WHEELS AXLE(FINAL DRIVE) Transmits rotary motion and torque from the engine-transmission-driveshaft to the wheels. Provides speed reduction and torque multiplication. Finally provide power from engine to road wheels (rear wheels) through many different steps.

14. PROCESS OF TRANSMISSION:

15. Transmission

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