a presentation on Coupling , crutches and Brakes

1. Coupling, Clutches
and Brakes
Prepared by:-
PARTH VIRANI 160110120061 -16MC065PARTH VIRANI 160110120061 -16MC065
YASH PATEL 160110120047YASH PATEL 160110120047
-16MC066-16MC066
NISHIT KARKAR 160110120024 -16MC067NISHIT KARKAR 160110120024 -16MC067
RAJAN BAROT 160110120001 -16MC068RAJAN BAROT 160110120001 -16MC068
RUPESH BHALARA 160110120003RUPESH BHALARA 160110120003
-16MC070-16MC070

2. Couplings
 What is Coupling?
 A Coupling is a device used to connect or
couple two shaft.
 Shaft are mostly available upto 7 meters
length due to transport difficulty.
 To get a greater length, it is necessary
to joint two or more pieces of the shaft
using coupling.

3.  What is the purposes of coupling?
1) To connect shafts of motor and generator
which are manufactured separately and to
provide for disconnection for repairs or
alternations.
2) To reduce the transmission of shock loads
from one shaft to another.
3) To allow misalignment of the shaft or to
introduce mechanical flexibility.
4) To introduce protection against overloads.

4. COUPLINGSCOUPLINGS
Rigid CouplingRigid Coupling Flexible CouplingFlexible Coupling
Sleeve or muffSleeve or muff
couplingcoupling
Flange couplingFlange coupling
Unprotected TypeUnprotected Type
Bush pin type FlangeBush pin type Flange
couplingcoupling
Universal couplingUniversal coupling
Oldham couplingOldham coupling
Clamp or split muff orClamp or split muff or
compression couplingcompression coupling
Protected TypeProtected Type

5. Split muff coupling(clamp coupling)

6. Sleeve or muff couplingSleeve or muff coupling
 This is the simplest type of rigid coupling.
 It is made from cast iron and very simple to design and
manufacture.
 It consists of a hollow cylinder whose inner diameter is
the same as diameter of the shaft .
 The hollow cylinder id fitted over the ends of the two
shafts with the help of taper sunk key.
 A key and sleeve useful to transmit power from one shaft
to the other shaft.
 It has no projecting parts. The main disadvantage of this
coupling is that it is difficult to assemble when there is no
perfect alignment between shafts.

7. Sleeve or muff coupling
Key
Shaft B
Shaft A Sleeve (muff)
Key
Shaft B
Shaft A
Sleeve (muff)
Sleeve (muff)
Shaft BShaft A
Key

8. Split muff couplingSplit muff coupling
(clamp coupling)(clamp coupling)
 In this coupling, the muff or sleeve is made into
two halves parts of cast iron and they are join
together by means of mild steel studs or bolts
and nuts.
The advantages of this coupling is that
assembling or disassembling of the coupling is
possible without change the position of shaft.
This coupling is used for heavy power
transmission at moderate speed.

9. Flange coupling
 This coupling is having two separate cast iron Flanges as
shown in figure a unprotected type flange coupling.
 Each flange is mounted on the shaft end and keyed to it.
The two flanges are coupled together by hep of bolts and
nuts.
 The projected portion of one of the flange and
corresponding recess on other flange are help to bring
the shafts into line and to maintain alignment.
 A flange provided with shroud which shelters the bolt
heads and nuts as shown in figure is called protected type
flange coupling.
 This flange coupling is most accurate and rigid. The
coupling provide the strong connection of shafts.

10. Unprotected type flange coupling

11. Protected type flange coupling

12. Bush pin type Flange couplingBush pin type Flange coupling
 This is a modified form of protected type flange coupling.
This type of coupling has a pins and it work as a coupling
bolts.
 The rubber or leather bushes are used over the pipes. The
coupling is having two halves are dissimilar in
construction as shown in figure.
 The pins are rigidly fastened by nuts to one of the flange
and kept loose in the other flange.
 This coupling is used to connect of shaft which having the
small parallel misalignment, angular misalignment and
axial displacement.
 In this coupling rubber bush absorbs shocks and vibration
during its operation.

13. Bush pin type flange coupling

14. Oldham’s couplingOldham’s coupling
 It consists of two flange A and B with slots and a central
floating disc E as shown in Figure .
 The disc E having tongues T1 and T2 at right angles. The
tongues T1 is fitted into the slot of float A and allows
horizontal sliding relative motion while the tongues T2 is
fitted into the slot of the flange B and allow for vertical
sliding relative motion.
 This right angle motions of tongues on the slots will
accommodate lateral misalignment of shaft when they
rotate.
 Oldham’s coupling is used in connecting two parallel
shafts but not in alignment, and their axis are at small
distance apart.

15. Oldham’s coupling

16. Universal coupling or Hooke’s JointUniversal coupling or Hooke’s Joint
 Universal coupling consists of two similar forks keyed on
the ends of the two shafts as shown in figure.
 These two forks are assembled to a central block by pin. A
central block having two arms at right angle to each
other.
 Universal coupling is used to connect two shafts whose
axis intersect.
 It two used to connect two shafts, where the angle the
angle between two shafts may be varied when they rotate.
 The universal coupling is widely used in automobile and
machine tools.

17. Universal coupling

18. ClutchesClutches

19. What is clutch?What is clutch?
 A A clutchclutch is a mechanical device that provides for the transmission of is a mechanical device that provides for the transmission of
power (and therefore usually motion) from one component (the drivingpower (and therefore usually motion) from one component (the driving
member) to another (the driven member) when engaged, but can bemember) to another (the driven member) when engaged, but can be
disengaged.disengaged.
 In the simplest application, clutches connect and disconnect two rotatingIn the simplest application, clutches connect and disconnect two rotating
shafts (shafts (drive shaftsdrive shafts or or line shaftsline shafts). In these devices, one shaft is typically). In these devices, one shaft is typically
attached to a motor or other power unit (the driving member) while theattached to a motor or other power unit (the driving member) while the
other shaft (the driven member) provides output power for work. Whileother shaft (the driven member) provides output power for work. While
typically the motions involved are rotary, linear clutches are also possible.typically the motions involved are rotary, linear clutches are also possible.
 In a torque-controlled drill, for instance, one shaft is driven by a motor andIn a torque-controlled drill, for instance, one shaft is driven by a motor and
the other drives a drill chuck. The clutch connects the two shafts so thatthe other drives a drill chuck. The clutch connects the two shafts so that
they may be locked together and spin at the same speed (engaged), lockedthey may be locked together and spin at the same speed (engaged), locked
together but spinning at different speeds (slipping), or unlocked and spinningtogether but spinning at different speeds (slipping), or unlocked and spinning
at different speeds (disengaged).at different speeds (disengaged).

20. General Diagram of clutch partsGeneral Diagram of clutch parts

21. Types of clutchTypes of clutch

22. Friction clutchesFriction clutches
 It is used to transmit the power between
two machine shaft which may require to
stop or start frequently.
 In automobiles Friction clutch is used to
connect the engine to the driven shaft.
 In operating such a clutch, care should be
taken so that the friction surfaces engage
easily and gradually brings the driven up
to proper speed.

23. Disc clutch (single plate clutch)Disc clutch (single plate clutch)
 It consists of two flanges. One is keyed rigidly to the
driving shaft, other is fitted to the driven shaft by splines
so that it can slide on shaft.
 In normal operation, both shaft remains engage due to
spring force.
 Single disc clutches are used in automobiles.
 When large torque transmission is required, The multi disc
clutch is used. Multi disc clutch has more number of
contact surfaces disc on driving and driven shaft.

24. Disc clutch (single plate clutch)Disc clutch (single plate clutch)

25. Cone ClutchCone Clutch
 The cone clutch consists of two cones, one
internal cone fixed to driving shaft, another cone
fitted on the driven shaft which is free to slide
axially on the driven shaft.
 The clutch is engaged by bringing two conical
surface in contact. Torque is transmitted by the
friction between contact surfaces of cone.
 The main advantage of this clutch is, it’s very
simple and require less axial pressure to
disengage the clutch

26. Cone ClutchCone Clutch

27. Centrifugal ClutchCentrifugal Clutch
 The centrifugal type clutch is a automated type
clutch, which operates on the basis of the Engine
speed.
 The clutch is automatically engaged and driven
equipment is smoothly brought up to the
operating speed.
 This clutches are highly useful for heavy loads
(Large Machines) where the motor cannot be
started under the load.

28. Centrifugal ClutchCentrifugal Clutch

29. Positive Contact ClutchPositive Contact Clutch
 This type of clutch engaged or disengaged without slip.
Therefore is known as Positive Contact Clutch. This clutch
is not suitable where Gradual engagement and
disengagement is required without stopping the Driving
Shaft.

30. The Jaw ClutchThe Jaw Clutch
 It consists of segmental projections or dogs on one of the
flange and corresponding recess on other flange on driven
shaft.
 The sliding flange engaged with the fixed flange to
transmit the mmotion and power from driving shaft to the
driven shaft.
 This clutch is used for transmission of power in
agricultural equipments like tractors, threshers, etc.

31. The Jaw ClutchThe Jaw Clutch

32. BRAKESBRAKES

33. Defination :Defination :
 A Brake is a mechanical device which
produce friction resistance against moving
machine member,in order to slow down or
stop the motion of machine.

34. Types Of Brakes:Types Of Brakes:

35. Block Brakes :Block Brakes :
1) Single block or shoe brake:
A single block is consist of a
block which is pressed against the
rim of revolving brake wheel drum.it
is used in railway trains & tram cars.

36. Single block or Shoe brake:Single block or Shoe brake:

37. 2) Double block or shoe brake:
 it consist of two brake blocks at the opposite ends
of the wheel.
these shoes apply force to both the sides of wheel
and reduces the
unbalanced force on the shaft.
 it is used in electric cranes.

38. Double block or shoe brakeDouble block or shoe brake::

39. Band Brake:Band Brake:
 A band brake consist of a flexible steel band lined
with friction
material,which wrap to the brake drum. when
upward forces applied
to the lever end, the lever turns about the fulcrum
pin and tightens
the band on the drum and hence the brakes are
applied.

40. Band brake:Band brake:

41. Internal expanding shoe brake:Internal expanding shoe brake:
 An internal expanding shoe brake consist of two
shoes.
 The outer surface of the shoes are covered with
friction material.
 Each shoe pivoted at one end about a fixed
fulcrum and other end rest against cam.
 The friction between the shoes and the drum
produced the braking torque.
 It is used in motor cars and light trucks.

42. Internal expanding shoe brake:Internal expanding shoe brake:

43. Disc Brake:Disc Brake:
 Disc brakes are different from drum brakes in that the
drum is replaced by a circular metal disc and the brake
shoe are replaced by a caliper which supports a pair of
friction pads, one on each side of disc.
 These pads are forced inward by the operating force and
also retard the disc.

44. Disk brake:Disk brake: