TRANSMISSION SYSTEM

TRANSMISSION SYSTEM

@ Mechanical Trnsmission goes to

Engine>Clutch>Gear Box>Universal jy.> Propellar shaft> differential>Drive> Rear wheel

 # Clutch :-

      The main function of clutch are to engage or disengege the engine power to the gear box
2. To help in shifting the gears in the gear box
3. To provide a smooth and gradual operation to take up load without job

i) Single Plate clutch  :-

    this is type of disc clutch . it uses a single disc called clutch . the fly wheel drives the clutch plate , which in term rotate the gear box shaft

# Construction :-

         a single plate clutch consist of three main parts
- Fly Wheel
- Clutch plate
- Pressure plate
 The single plate clutch , the fly wheel is attached to engine shaft and act as a driving member . the clutch plate is a steel disc. there is friction lining on both side of the steel disc. the lining are binded on the steel disc. the pressure plste is generally mode of high tensile grey iron. it is a disc which exert pressure on the clutch plate to keep it engage to the fly wheel

# Working :-

          The clutch remain in engage position. when the clutch padel is pressed . the pressue plate is moved to the right against the force of the spring with this movement of the pre+
-ssue plate ,the clutch is disengage . when the pressure is removed from the clutch padel the spring against excert the pressue on the pressure plate , which in term engage , the clutch plate to the fly wheel , the clutch plate is mounted on a supplying shaft . so, the supplying shaft starts rotating the other end of which is attach to the gear box

# Advantages :-

  - The padel movement is less
- Gear shifting is easier
ii) Multi plate clutch :-
   multiple plate clutch consist of more than one clutch plate and driving plate. as these are many clutch plates . the friction area is increased and hence, the capacity of the clutch transmit mor torque , it is also caleed multi plate clutch

# Construction :-

            These are of two type of friction plates one type have grooves or teeth on the outer surface, these groove are fitted with fly wheel the other type have grooves oor teeth in inner side and these plates are fitted on spline shaft . the rest of contruction is same as single plate clutch . a pressure plate keeps the pressure on the friction plates with the help of springs , the spring may be coil spring or diaphrames spring, these is a clutch lever which can push back the pressure plate against spring

# Working ;-

       The outer teeth plate rotates with the fly wheel . the inner teeth plates having friction lining are fitted on the spline shaft, in engaged position the spring pressure causes to push the pressure plate on the clutch plates and inner plate come in contact with the outer plates and rotates , the power is transmitted  to the gear box shaft when the clutch padel is pressed, it pulls back the pressure plate and the inner plates arerelased , hence the clutch is disengaged

# Advanatge :-

   - since the number of clutch plates are more , the friction surface area is increased and clutch can transmitted more torque
- For The same amount of torque, the torque is divided among many plates and hence smaller plates are required .so the size of clutch is reduced fot the same torque
- heat dissipation is easier as there are many surfaces to dissipate heat

# Uses :-

   the multiple clutch is used in heavy transport vehicles are racing cars as it can transmit high torque. it is also used in motorcycle since it take less space

iii) centrifugal clutch :-

 it is an automatic clutch , no clutch padel is recognised to control  the clutch operation . it is controlled by the centrifugal forces, the engagement and disengagement operation depends upon the engine speed which is controlled by the accelerator

# Construction :-

        A bell crank lever is used with a mass one side and the other side is in touch with an intermediate plate, there is spring in between the intermediate plate and clutch plate, the clutch plate has friction lining on it , when it is pressed it comes in contact with the flywheel

# working :-

  the bell crank lever rotate with fly wheel , when the speed of the engine increases, the mass flies outward thus the lower presses the intermediate plate . which pusses the clutch platye with the help of spring so, the clutch plate is engaged with the flywheel and the power of the engine transmitted to the gear box shaft as the speed is further increased the pressure on the clutch plate and it is engaged more perfectly . to disengage the clutch the pressure on the accelerator padel is removed by this way the engine speed is decreased and the mass comes to it original position
     thus the pressure on intermediate plate is removed and the clutch is in desengaged position

# advantages :-

  - The clutch operation is automatic
- Clutch padel is not required to operate the clutch

iv) Semi centrifugal clutch :-

         is useful clutch is useful for high torque transfer small  stiff spring are required for high torque transfer small stiff spring are required for high torque transfer as the stiffness is more higher load on clutch paddle is required , this higher load requirement cause fatique to the driver avoid this fatique centrifugal force is used to activate the pressure plate

# Construction :-

        the construction of semi centrifugal clutch is always similar to single plate clutch is almost simislar to single plate clutch . the fluy wheel clutch plate and the pressure plate are arrange in same manner as single plate clutch springs are also to keep the clutch partially engage , the lever are hinged on the pressure plate,the outer are is called weight arc

# Working :-

 when the clutch paddle is pressed the clutch is disengage after releasing the clutch paddlethe spring pressue pusses the pressure plate and the clutch is engaged. the clutch start working at the normal speed. when the speed increase the centrifugal force moves to the weight arm of the lever start pressing the pressure plate by this way the suffiecient amount of torque is transmitted as higher speed . when the speed is lower the weight are start to fall the inner arm is recret

# advantage :-

    - For high torque transmission , less afford bis required for clutch operation less
- less afford as compare to single plate clutch

@ Gear box :-

     - it provide high torque at starting and high speed while running
- Gear box also provides to reversed direction of the vehicle
- it provides a neutral position, the position at which the power flow to rod wheel disconnect

@ Siding gear box
# construction :-

      This type of gear box is attached the clutch A is alwaysmeshed with lay shaft gear . There are 3 more other gear fixed on the lay shaft . there is also an ideal shaft on which a small ideal gear M is mounted . this ideal gear is used for reversing the direction . there  is a m ain  shaft which  is allived to the clutch shaft 2 gears  A and C are  mounted on the main shaft such that they can slide on shaft

# working :-

    the gear A is also rotating and the clutch is engaged . the gear O,E, F ,G and H also rotate with gear a neither gear B nor gear c is meshed with any of gear of shaft

i) First Gear :-

      to Position the gear box in first gear . the gear C is slide on the main shaft such that it is mershed with gear F, now the main shaft starts rotating . the power isa transmitted from clutch shaft through ADFC to the main shaft

ii)Second gear :-

       The position of gear box in second gear, the gear B is slided on the main shaft such that it is meshed with gear E, now the power is transmitted from clutch shaft through gear ADEBC to the main shaft

iii) Top shaft :-

           the position of gear box in top gear . the gear B is slided on the main shaft . such that it is directly enghage to gear A. so the power is transmitted without any reduction

iv) Reverse gear :-

         the position of gear in reverse gear. the gear C is slided on the gear shaft such that it is meshed with the ideal gear H. in this position power is transmitted fromclutch shaft through gear

# Constant mesh gear box :-

           these gear may be spur gear or  hgelical gear. but helical gear  are prteffered but their running is quite , there is a gear is mounting on the clutch shaft the gear E,F,G,H . the gear E is always mesh with gear A . the gear B,C andD . rotate freely on the main shaft. there is an ideal gas I mounted on the ideal shaft, the gear B is always F anf the gear C is Always gear C and D is called is called reverse gear and always mesh with gear I and H . there are also to dog clutch mounted directly on the the main shaft. the dog clutches have teeth on them which can be engaged with the main shaft gear teeth

# Working :-

      - neutral position :-
                   all the gears are rotating but the dog clutches are not engaged with any of the  gear

i) first gear :-

         for postioning the gear box in 1st gear. dog clutch D2 is slided on the main shaft toward left such that the teeth of dog clutch are engage with the teeth of gear C. the power is transmitted AEGC and D2 vto main shaft
# Propellent shaft :-
       This shaft is used  to transmitted power from transmission to real axle or differential in case of rear wheel drive vehicle these shaft does not remain at fixed position . there are 2 main reasonn for these
- The real axle moves up and down  because of uneveness of the road
- While breaking and starting it tends to mmove fprward and backward for the first reason there is universal it but for second reason an arrangement as to be provided so that its axial arrangement is called slip joint'
# Universal joint :-
            these joint is used to connect two shaft whose axis are inclined to each other in an automobile , the axis of transmission shaft and propellar shaft is not in line such that they are inclined to each other , so that the universal joint used to transmit power from transmission shaft to propellar shaft most commonly used universal joint is hook joint
# Function :-
        the power wheel transmitted by the propellar shaft has to be transmitted to real axle which are at right angled to the propellar shaft. also while the vehicle is taking a tirn suppose right turn then the right wheel should have lesser space than the left wheel . if the is not so, the right wheel get skits , for both of these reason a device called differential is used
      - it transmits power function of differential
- it helps the vehicle to takle a turn smoothly by reducing the spped of inner wheel and increasing the speed of outer wheel
# principle :-
       it work on the principle that when two bevel gear are meshed with bevel at high angled then the 2 gear will rotate in opposite direction at same speed
# construction :-
         the simple digram consist bevel pinion attached to propellar shaft through universal jpoint to this bevel pinion is meshed and crown  wheel which rotate freely on axle sahft
            there are 2 planet pinion attached to the case , this rotate free on the case spindle to the planet pinion are attached to sun gear
# working :-
       When the vehicle is going striaght the whole arrangement works as a unit . the power flow bevel pinion to crown wheel , case to planet pinion and to sun gear which rotate the axle shaft . the power is equally divided between , the sun gear and the speed is equal to NRpm
          now , if the vehicle has to take turn towards right then the wheel of the right side will tends to reduce its speed, say n rpm , this will rotate the left sun gear by n rpm in opposite direction by this way the speed of the n rpm and it will be N-n , simultaneously the speed of the left axle shaft increase by n rpm and it will be N-n . so, the vehicle will turn smoothly without skit

# rear axle :-

          axle is a shaft which tramitted power from differential to 2 wheel , the rear axle is not a single shaft but it is divided into two shafts , one is for left and right wheel each of this part is called half shaft beside transmitting power, it also withstand the weight of the body

# Function of rear axle :-

       - it is transmit  power from differential to wheel
- it take load of the vehicle

# types of rear axle :-

- Semi floating axle :-
            in this type of axle all the load taken by the the axle shaft, this type of axle is used for cars
- Fully floating Axle :-
               all the load is taken by the wheel and axle losing . this type of axle is used for heavy vehicles
- Three quarter axle :-
           it comprise between semi flosting anf full flosting axle , in this type a part of the load is taken by the axle casing and the party by the axle itself

 @ steering Geomatry ;-

       camber is the tilted of the wheel at top form the vertical postion, if the tilt at the top is outward, camber is positive and if the tilt at the top is inward , camber is negative both postrive and negative camber

_ Caster :-

              cater is the angle between vertical and the axis of the king pin, postive and negative caster angle , the caster angle is pposiyive when the king pin axis meets the ground at a point in front of the wheel centre and it is negative when the king pinaxis met the ground at behind the wheel centre. .the angle provide is 3 Degree most

- King pin Inclination :-

        king pin inclination is the angle between verticle and king pin axis, if the king pin is not inclined them the rod shock will be transmitted to steering wheel . king pin inclination is not adjustable , it is decided by the manufacture, how ever its right anglee is to 6 to 8 degree

- Toe in And Toe out :-

           the toe in which the amount by which the front of front wheel is set close than the rear of the front wheel then toe is equal To B-A
            Toe out is the amount by which the rear or front wheels then toe out is equal to A-B

# Wheel And Tyres :-

          Wheel and tyre assembly is the log of the vehicle . A vehicle cannot run without it, this assembly drives the vehicles and takes its load also wheel are fitted on wheel hub . all the wheel are fitted tyres. which remain in contact with the rod surface

# types of wheel ;-

    - Disc wheel :-
          it consist of two parts
* rim 

* other steel disc :-

         both the rim and the disc may be single piece or welded to each other , the  disc can be mounted on the wheel hub with the help of bolts and nuts , the tyres are fitted on the rim . the steel disc is mounted on the axle with the help of bolts and nuts
- Wire wheel :-
      a wire wheel have three three main parts
* Rim
* Hub
* Wire spoker
the hub is attached to the rim through these spokes. the spoke withstand the vehicle rod and transmit the driving and breaking torque. the spokes are long thin wires one side as thread . the stop side fitted to a hub and the thread side is attached to the rim
# tyre :-
    tyre is that part of a vehicle which have a contact with a road surface it is mounted on wheel and fix over the rim of the wheel
- tubed tyres         - tube less tyre

i) Tubed tyre :-

        they have mainly two type
* carcass :-
      it is the basic structure of the tyre and it take take various loads , it consist of a number of layers of corts called plies. the cort is made uo of of nylon. yhe number of plies tyre may have four to six plies and truck tyre have upto 22 plies
* Thread :-
       thread is the outermost part of tyre which comes in contact with the road surface
* Beads :-
      beads are the coil of steel wires these are the form as the inner edge
* Tube :-
       it is inside the tyre and contain air under pressure . it is for filling air

ii) tUBE less tyre :-

        the cconstruction of tyre is same as the tyre, the only difference is that there is an air rwtaining liner inside the tyre in plavce of tube . there is a valve on rim side for inflating and deflating the tyre