1. THEORY OF MACHINE FRICTION CLUTCHES PREPARED BY:-
JIGNESH TALAVANIA( )
DEV MAKATI( )
PARIMAL PATEL( )
GUIDED BY
NITIN R. PATEL

2. clutch
A Clutch is a machine member used to connect the driving shaft to a driven shaft to transmit power, so that the driven shaft may be started or stopped at will, without stopping the driving shaft.

3. Function of clutch
Clutch is used to transmit power from driven shaft to driving shaft.
In automobiles, where vehicle can be stopped for a while or to change the gear, the requirement is that the driven shaft should stop but the engine should run naturally under the no load condition.
This is achieved by using clutch mounted between engine shaft and gearbox shaft and which is operated by a lever.

4. CONE CLUTCH

7. ENGAGED CONDITION

8. DIS-ENGAGED CONDITION

9. As per Uniform Wear Theory
pr1= constant
W=2πpr1(r1 – r2)
And,
T=µ*W*R*
where R=(r1+r2)/2

10. As per fig.,
r1-r2=b

11. PLATE CLUTCH
SINGLE PLATE CLUTCH

12. CONSTRUCTION
A single disc or plate clutch consists of a clutch plate whose both sides are faced with a frictional material.
It is mounted on the hub which is free to move axially along he splines of the driven shaft.
The pressure plate is mounted inside the clutch body which is bolted to the flywheel.

13. CONSTRUCTION
The pressure plate pushes the clutch plate towards the flywheel by a set of strong springs which are arranged radially inside the body. The three levers (also known as release levers or fingers) are carried on pivots suspended from the case of the body.
Both the pressure plate and the flywheel rotate with the engine crank shaft or the driving shaft.
These are arranged in such a manner so that the pressure plate moves away from the flywheel by the inward movement of a trust bearing.

14. WORKING To engage the clutch, the contact lever is gradually released.
Then a spring provides an actuating force to the driven disk forcing it to move towards the driving disk and finally makes contact with it.
The driven disk starts rotating at low speed due to the friction between the disks.

15. WORKING
When the contact lever is fully released, the spring provides the required axial force to press the driven disk against the driver disk, the friction force between them increases, and the driven disk attains the speed of the driver disk.
Torque is transmitted by means of frictional force between these plates.

16. During disengagement of the clutch, a contact lever keeps the driven disk away from the driving disk.
There is no contact between driving disk and driving disc.
The disk attached to the driving shaft rotates with the speed of the engine to which it is attached, and the disk attached to the driven shaft remains in the ideal condition till the engagement.

17. PLATE CLUTCH
MULTI PLATE CLUTCH

18. CONSTRUCTION
Clutch plate is mounted on the hub which is free to move axially along he splines of the driven shaft.
The pressure plate is mounted inside the clutch body which is bolted to the flywheel.
Both the pressure plate and the flywheel rotate with the engine crank shaft or the driving shaft.
The pressure plate pushes the clutch plate towards the flywheel by a set of strong springs which are arranged radially inside the body.

19. CONSTRUCTION
The multi plate clutch has friction lining on both the side except the first the side which is adjacent to the flywheel.
This plate has friction lining on one side.
The friction plate are connected on the top of the flywheel.
Hence friction plate rotates with the flywheel and hrnce with driving shaft.
It consists of more than one set of disc plate and friction plate. The one set of plate’s slides in grooves on the flywheel and other one slides on splines on the pressure plate hub. Alternate plates belongs to each set.

20. WORKING
When the pressure is applied to the foot pedal, the pressure is transmitted .
Then the springs are compressed and its moves back the pressure disc thus releasing the clutch plate.
Now the clutch is said to be disengaged.
At this stage the pressure plate and flywheel are free to rotate with clutch plate stationary.
CONTD..

21. Similarly when the clutch pedal is released, spring pressure is fully applied on the clutch plate.
The plate is held between flywheel and pressure plate and rotates as a single unit.
Hence the clutch is said to be engaged.