The document describes the differential mechanism, which is used in automobiles and other machinery to allow wheels to rotate at different speeds. It discusses how a differential works using bevel gears to distribute torque from the engine to the left and right wheels. The differential has three main functions: to direct engine power to the wheels, act as a final gear reduction, and allow the wheels to rotate at different angular velocities, such as when turning. Diagrams illustrate the components of a differential including side gears, spider gears, and pinion gears.

1. One Of The Most
IntelligentEngineering
Inventions
Differential Mechanism

2. STORY
• If you have a car with an engine whose shaft
connected directly to the back wheels of the car .
• One morning when you drive to your faculty you
want to turn right and because the back wheels
of your car rotate or move with the same speed
your car will be out of control and start drifting .
• So it is a problem and let’s engineering it .
• After days of searching , we found a solution .
• We will use a car differential mechanism .
• So let’s do it .

3. DEFFINITION
• A Differential is a gear
train with three shafts
that has the property
that the angular velocity
of one shaft is the
average of the angular
velocities of the others,
or a fixed multiple of
that average.

4. TYPES
 There two types :
• Spur-gear differential
(selected)
• Epicyclical differential
• Bevel gear differential
(open differential)

5. APPLICATIONS
 There are many applications :
 mechanical analog
computers
 Automobiles
 Clocks
 Mills
 Chinese south-pointing
chariots

6. BEVEL GEAR DIFFERENTIAL(SELECTED)
 Bevel gear differential(open differential)
is the most popular type of differential
mechanism because of it’s used
in a wide range of fields and here
is some of its applications .
 Application :
• Automobiles
• Mills

7. FUNCTION(automobiles)
 The differential has three jobs:
•To aim the engine power at the wheels .
•To act as the final gear reduction in the
vehicle, slowing the rotational speed of the
transmission one final time before it hits
the wheels .
•To transmit the power to the wheels
while allowing them to rotate at different
speeds (This is the one that earned the
differential its name).

8. DIFFERENTIAL COMPONENTS
• Right axel shaft
• Left axel shaft
• Side gears
• Spider gears
• Ring gear
• Pinion gear
• Power shaft

9. HOW DOES IT WORK ?
• The power shaft drives the pinion gear which
transmits torque to ring gear .
• In straight driving the ring gear transmits torque
to the two side gears which rotate at the angular
velocity but the spider gears doesn’t rotate .
• In case of make a turn the back wheels should
rotate at different speeds so outer wheel will
rotate faster than the inner wheel .
• The spider starts to rotate and as a result, it
absorbs some of angular velocity of the inner
wheel make it rotate at a slower manner
compared to the outer wheel .

10. ASSEMBLY AND ANIMATION

11. SIMPLYFING

12. OUR WORK
(fourstages)

13. BACKGROUND(first)
• we make a background for our project
through :
• Search into the Internet .
• Watching videos on Youtube .
• Reading some handbooks .
• Search into Wikipedia website .
• Visiting some websites and blogs .

14. DESIGN(second)
 Design of gears
• The main factors affecting on gear
matching is gear module .
• After choosing the suitable
parameters we start to cad it .
• Check our results through
simulation and testing .

15. CUTTING GEARS & BUYING MATERIALS(third)
• We cutting gears by using of
laser cutting machine after
buying materials of them .
• We go to market and buying
other materials including
steel bars , bearing , nuts ,
bolts , shafts , ……etc .

16. FINAL ASSEMBLY & TESTING(forth)
• After collecting all materials
we make our final assembly .
• We testing our assembly in
many situation including cases
of drive one wheel and making
the two wheels rotate with
different angular velocities .

17. REFERENCES
• H. B. Pacejka, Tire and Vehicle Dynamics, SAE Inc.
2002 .
• T. Newton, How Cars Work, Vallejo CA: Black Apple
Press, 1999 .
• Wikipedia the free encyclopedia .

18. USEFUL LINKS
• Youtube :
https://www.youtube.com/watch?v=yYAw79386WI&t=48
9s
• Wikipedia :
https://en.wikipedia.org/wiki/Differential_(mechanical_de
vice)
• Grabcad :
https://grabcad.com/library?page=5&time=all_time&sort=
recent&softwares=solidworks&query=differential