Paper solution summer -2012 be VIII sem subject: automobile engg

when clutch is in engage position due to frictional contact the flywhhel and pressure plate drives the clutch plate and as the clutch plate is mounted on the clutch shaft which is also called gear box input shaft power transmit from engine to transmission and when clutch is disengage position there is no frictional contact between flywheel pressure plate and cluth plate and no power is transmitted to clutch and thus power from engine doesn’t flows to the transmission system

1) less costlier as only single plate is used.

2) less maintenance due to single plate

Disadvantages:

1) large space reqired.

2) less torque transmission as compared to multiplate clutch.

Application :

Almost all four wheeler manufacturer used single plate clutch like maruti,Mahindra & Mahindra,tata,general motors,Hyundai,Toyota,volwwagon etc.

Q.3.A) Explain with neat sketch construction and working of synchromesh gear box.

ANS:

Synchromesh gear box is an extension of constant mesh type of gear box.The construction of synchromesh gear box is same that of constant mesh type of gear box except one additional device used in synchromesh type of gear box known as synchronizer ring.

When the gear is shifted from higher to lower or from lower to higher in case of constant gear box the driver has to double de-cluth while shifting the gear due to un equal speed otherwise there will be large noise in gears and wear and tear.The double de-clutching and wear tear is avoided in Synchromesh gear box because the synchronizer ring equalize the speed first before engagement and then smoothly engaged the clutch.

2) Less wear and tears in gears .

3) less noisy.

Disadvantages:

1. 
   Complicated design.
   
2. 
   expensive.
   

Employed in almost all type of light,medium and heavy passenger and commercial vehicle in high geas only or on all the gears.

The propeller shaft is used in automobile to transmit rotary motion from gear box to differential where there is large distance between them .it’s just a shaft fitted with universal joint on both the ends and splines shaft on one side.

One end of propeller shaft connected with gear box output shaft with one universal joint and its another end is connected with final drive with the help of another universal joint.when the vehicle run on road its wheel moves up and down due to road ir-regularity thus the whole differential assy also move up and down this changes the angle of power transmission between the propeller shaft ,gear box and differential .To meet the change in angles universal joints are used which permit torque transmission at different angle.

Also due to upon and down movement the length of propeller shaft also varies and to meet this sliding joint is provided in propeller shaft which accommodate the change in length.