- Clutches connect two rotating shafts to allow a driven shaft to be engaged and disengaged without stopping the driving shaft. - There are several types of clutches including positive/dog clutches, friction clutches, and centrifugal clutches. Positive clutches couple shafts through interference rather than friction. Friction clutches come in single and multi-plate varieties. - The document discusses the design and torque transmission calculations for single plate clutches. It covers both the uniform pressure and uniform wear theories for calculating the torque transmitted based on the axial loading and dimensions of the clutch plate.

1. Clutches
Presented by
Pratyush ranjnan kar
M-tech manufacturing technology
Regd no.- 163510

2. Basic idea
 Clutches are useful devices with two rotating shafts
 It connects the driving shaft to a driven shaft, so that the
driven shaft may be started or stopped at will, without
stopping the driving shaft
 In a drill,,one shaft is driven by a motor and the other is
driving a drill chuck. The clutch connects the two shafts so
that they can either be locked together and spin at the same
speed, or be decoupled and spin at different speeds

3. Types
Types of
Clutches
Positive
Clutch
Friction
Clutch
Plate Or
Disc Clutch
Single plate
clutch
Multiplate
Clutch
Cone Clutch
Centrifugal
Clutch

4. Positive Clutch/ dog clutch
 It couples two rotating shafts or other rotating
components not by friction but by interference.
 It is Simple to construct, No heat generated , No slip,
Compact ,Low cost.
 But it Must be connected when shaft is unloaded.
 Uses- power press and rolling mills

5. Friction clutches
Single plate clutch
Multiplate clutch

6. Centrifugal clutch
Driving
shaft
Driven
shaft
F=mrω
2
ω
ω
Cone clutch

7. Design and torque transmitted
Area of the ring on contacting surface
rrA  2
Axial load on the ring
rrpW  2
Frictional resistance offered by ring
rprWFr  2
Frictional torque acting on ring
rprrFT rr  2
2
Torque transmitted is obtained by considering following
two assumptions:
a) Uniform pressure theory
b) Uniform wear theory

8. p = Constant
 
T R
R
r rprT
0
2
1
2
2 
rrpT
R
R
T
r   
1
2
2
0
2
Torque transmitted
 3
2
3
1
3
3
2
3
2
1
2
RRp
r
pT
R
R






 
  3
2
3
12
2
2
13
2
RR
RR
W
T 












 2
2
2
1
3
2
3
1
3
2
RR
RR
WT 
Uniform pressure theory

9. Uniform wear theory
 In this theory, we are considering that wear which take place is
uniform over the entire contacting surface i.e.
p.r = Constant
So, p = C/r
 We know that axial loading acting on the ring is,
Integrating above equation within limits we get,
rCW
rr
r
CrrpW


2
...2...2.


   
 21
21
0
2
22
2
1
2
1
2
RR
W
C
RRCrCW
rCW
R
R
R
R
W



 




10. We know that, frictional torque acting on the ring is,
Torque transmitted by single plate clutch can be obtained by integrating the
equation within the limits R2 to R1 we get,
rCrrr
r
C
T
rprT
r
r


22
2
2
2


 
 2
2
2
1
2
2
2
1
2
0
0
2
2
2
2
2
2
1
2
1
2
1
2
RRCT
RR
C
r
CT
rrCT
rrCT
R
R
R
R
T
r
R
R
T
r


















11. • Power transmitted by single plate clutch is given by,
Where, N = Speed of driving shaft
Watt
NT
P
TP
60
2
.



