Power transmission in Automobiles

3. The mechanism that transmits the
power developed by the engine of
automobile to the engine to the driving
wheels(rear wheels) is called the
TRANSMISSION and the system is called
TRANSMISSION SYSTEM.
 It is used to transmit engine torque to
the driving wheels to drive the vehicle
on the road.
.

4. Provide means of connection and disconnection of engine with
rest of power train without shock and smoothly.
Enable power transmission at varied angles and varied
lengths.
 Provide means to drive the driving wheels at different speeds
when required.
 Provide a varied leverage between the engine and
the drive wheels

5. ENGINE
FLYWHEEL
CLUTCH
GEAR BOX (or) TRANSMISSION BOX
UNIVERSAL JOINT
PROPELLER SHAFT OR DRIVE SHAFT
DIFFERENTIAL
REAR WHEEL AXLE
REAR WHEELS

6. Engine is a mechanical
device which converts the
chemical energy of a fuel into
heat or thermal energy and
then converts the heat energy
into mechanical energy and
makes the vehicle to run at
different loads.
Engines are again classified
into IC or EC Engines and are
used for different purposes.
So the main purpose of
engine is to transfer
mechanical energy to different
parts of the transmission
system by the crankshaft.

7.  A FLYWHEEL is connected to
the crankshaft of the engine
which is a rotating device.
FLYWHEEL is a body having
large mass and it act as a
reservoir for energy store
coming from the engine.
It stores energy from engine
when it is more and releases
the energy when it is more than
requirement.
In IC engines power produced
in one stroke and the remaining
three strokes are idle. So in
that case a Flywheel supplies
energy to all the rotating parts
and makes the crankshaft to
run at uniform speeds.

8. The purpose of clutch is to engage
and disengage the transmission
system from the engine when a
vehicle is being driven away from a
standstill and when the gearbox gear
change is necessary. The gradual
increase in the transfer of engine
torque to the transmissions roust be
smooth.
When the clutch is in the coupling
(normal running) position, power
flows through it from the engine to
the transmission. If the transmission
is in gear, then power flows on
through to the propelling wheels of
the vehicle.
The clutch contains a friction disc,
spring arrangement and pressure
plate for pressing this disc tightly
against the smooth rear face of the
flywheel.

9. •This GEAR BOX is considered as
the heart of the transmission
system.
• It is located between Clutch and
Propeller shaft .
• Gear box varies the leverage
(speed ratio & hence torque
ratio) between the engine
&driving wheels.
• It is provided with either 4
speed or 5 speed ratios or more
depending on design.
to change the gears to travel at
different speeds.

10. A UNIVERSAL JOINT is used to
transmit power from gear box to
PROPELLER SHAFT. And then from
PROPELLER SHAFT to DIFFRENTIAL.
So to maintain uniform speed and
mation,two universal joints are
used, one b/w gear box and drive
shaft and anoher b/w drive shaft
and differential and the coupling is
called universal coupling.
They are designed to to eliminate
torque and speed fluctions(for
constant velocity)
If only one universal joint isused,
speed fluctuations will not be
neutralized

11. Front engine rear wheel drive
Reduction in car height (lowering of
body).
It propels the vehicle forward, so called
propeller shaft.
A Propeller Shaft connects a gearbox to a
Differential.
It is used to transmit the drive force
generated by the engine to the axles.
It is provided with two U-joints to
maintain constant velocity and
positioning of differential at different
plane.
It is provided with a slip joint to take
care of the change inlength.
It is strong enough to handle maximum
low gear torque.

12. To transfer the engine
power to the rear wheels.
To act as the final gear
reduction in the vehicle.
To make the wheels to
rotate at different speeds
neglecting the turn.
It is provided with
different gears to transmit
power to rear wheels.

13. Transmits rotary motion
and torque from the
engine-transmission-driveshaft
to the wheels.
Provides speed reduction
and torque multiplication.
Finally provide power from
engine to road wheels (rear
wheels) through many
different steps.

16. THANK YOU
T.RAMBABU
MECHANICAL –B
12A91A03B9