Scene 1

>Nom: Affricot Dominique Savio 
 
WE are going to talk about the “Types of manual transmission and transaxles that are currently 
in use.  
After studying this chapter, the reader should 
be able to: 
1. Define torque and explain the relationship between torque and horsepower. 
2. Describe the various gear types and their effect. 
on speed, torque and direction of rotation. 
3. Explain gear ratios and their effect on vehicle operation. 
4. Discuss the types of manual transmissions and 
transaxles that are currently in use. 
5. Discuss automatic transmissions and the planetary gear sets used for automatic 
transmissions. 
6. Compare rear-wheel drive, front-wheel drive, 
four-wheel drive, and all-wheel drive systems. 
7. Explain the characteristics of drive shafts and 
drive axle assemblies.

Scene 2

>1-Let define first transmission what does it do? It’s purpose etc. A transmission is a machine in 
a power transmission system, which provides controlled application of power. Often the term 
5-speed transmission refers simply to the gearbox, that uses gears and gear trains to provide 
speed and torque conversions from a rotating power source to another device. Why we need 
transmission in automobile, Then? 
fig 1 
Single stage gear reducer 
 
The need for a transmission in an automobile is a consequence of the characteristics of the 
internal combustion engine. Engines typically operate over a range of 600 to about 7000 rpm 
(though this varies, and is typically less for diesel engines), while the car's wheels rotate 
between 0 RPM and around 1800 RPM. 
Furthermore, the engine provides its highest torque and power outputs unevenly across the rev 
range resulting in a torque band and a power band. Often the greatest torque is required when 
the vehicle is moving from rest or traveling slowly, while maximum power is needed at high 
speed. Therefore, a system is required that transforms the engine's output so that it can supply 
high torque at low speeds, but also operate at highway speeds with the motor still operating 
within its limits. Transmissions perform this transformation. What is the purpose and function 
of gears in a transmission?

Scene 3

The purpose and function of gears in a transmission include the following:

- Low/first gear must provide enough torque to get the

- High gear should provide an engine speed for fuel-efficient

- The intermediate ratios should be spaced to provide

adequate acceleration while minimizing the potential of

overrevving the engine before the shift or lugging the

A manual transmission, also called a standard transmission, is constructed with a

group of paths through which power can flow with each path used being a different gear ratio. 
Synchronizer assemblies or sliding gears and the shift linkage are used to control or engage the

Scene 4

output
shaft
input
shaft
clutch housing
synchronizer
counter
shaft

Scene 5

CLUTCH Engine power must be stopped when making a shift in a manual transmission. The 
clutch is used to stop the power flow to allow the transmission to be shifted. It is also used to 
ease the engagement of the power flow when the vehicle starts from a standstill. The slight 
slippage as the clutch engages allows the engine speed to stay up where it produces usable 
torque as the vehicle begins moving. Most vehicles use a foot-pedal-operated single-plate 
clutch assembly that is mounted on the engine flywheel. When the pedal is pushed down, the 
power flow is disengaged and when the pedal is released, power can flow from the engine to 
the transmission through the engaged clutch.

There some clue words we must know their meaning and their purpose in a transmission. Let 
talk about torque and explain the relationship between torque and horsepower.

DEFINITION Torque is a rotating or twisting force that may or may not result in motion. A 
vehicle moves because of the torque the drive axle exerts on the wheels and tires to make

Scene 6

them rotate. Being a form of mechanical energy, torque cannot be created or destroyed—it is 
converted from one form of energy to another form of energy.

The unit for torque is expressed as a force times the distance (leverage) from the object. 
Therefore, the official unit for torque is lb-ft (pound-feet) or Newton meters (a force times a 
distance). However, it is commonly expressed in ft-lb and most torque wrenches are labeled 
with this unit.

The drive gear is the gear that is the source of the engine torque and rotation. The driven

gear is the gear that is driven or rotated by the drive gear. Two gears meshed together are used 
to transmit torque and rotational motion. The driven gear can then rotate yet another gear. In 
this case, the second gear becomes the drive gear, and the third gear is the driven gear.

TORQUE MULTIPLICATION The gear teeth are cut proportional to the diameter of the gear. If 
one of two mating gears were twice as large as the other, it would have twice as many teeth. 
For example, if the smaller gear has 10 teeth, a gear twice as large will have 20 teeth.

If the teeth of these gears are intermeshed, 10 teeth of each gear will come into contact when 
the smaller gear rotates one revolution. This will require one revolution of the small gear and 
one-half revolution of the larger gear.  It will take two revolutions of the small gear to produce 
one revolution of the larger gear. This is a gear ratio of 2:1, assuming that the small gear is the 
drive gear. To determine a gear ratio, divide the driven gear by the driving gear.

Torque is increased because of the length of the gear lever, as measured from the center of the 
gear. Think of each tooth as a lever, with the fulcrum being the center of the gear. The lever 
lengths of the two gears can provide leverage much like that of a simple lever. Physics does

not allow energy to become lost in a gear set, other than what is lost as heat in overcoming 
friction. Therefore, whatever power that comes in one shaft, goes out through another.

Scene 7

The term power means the rate of doing work. Power equals work divided by time.

- Work is done when a certain amount of mass (weight) is moved a certain distance by a force. 
Whether the object is moved in 10 seconds or 10 minutes does not make a difference in the 
amount of work accomplished, but it does affect the amount of power needed.

- Power is expressed in units of foot-pounds per minute.

One horsepower is the power required to move 550 pounds one foot in one second, or 33,000 
pounds one foot in one minute (550 lb × 60 sec = 33,000 lb).

Lever Principles
Gears can be thought of as levers, the size of the gears will
effect the mechanical advantage
Load
Gear 1
RI
Lever
Load
Gear 2
RI
If RI and R2 are the same size there is no
mechanical advantage. When the gears are
different sizes(R1 R2) it will effect the
mechanical advantage of the gearset.
For example: Mechanical advantage can be used
on a robotto increase its abilityto push or lift
heavier objects

Scene 8

Mathematically, horsepower equals torque multiplied by rpm. H = T x rpm/5252, where H is 
horsepower, T is pound-feet, rpm is how fast the engine is spinning, and 5252 is a constant that 
makes the units jibe. So, to make more power an engine needs to generate more torque, 
operate at higher rpm, or both.

4-What are the types of manual transmission?

Crank
Horse Power
1 Hp = 550 ft.lbf/s
550 lb
t = 1 Second
550 lb
1 Feet

What's the relation between
Horsepower & Torque?
Know your required RPM & Torque?
IJse this equation to find your HP
RPM x Torque
5250
Know your required HP & RPM?
Use this equation to find your Torque
HP x 5250
Torque
RPM
Electric Motor

Scene 9

3 different types of manual transmission include Sequential manual transmission, 
Unsynchronized transmission, and constant mesh gearbox.

5-An automatic transmission (sometimes abbreviated to auto or AT) is a multi-speed 
transmission used in motor vehicles that does not require any driver input to change gears 
under normal driving conditions.

The most common type of automatic transmission is the hydraulic automatic, which uses a 
planetary gearset, hydraulic controls, and a torque converter. Other types of automatic 
transmissions include continuously variable transmissions (CVT), automated manual 
transmissions (AMT), and dual-clutch transmissions (DCT).

6-Both AWD and RWD setups deliver superior performance compared to FWD vehicles, but 
which one you choose will depend on your own priorities. ... RWD for Efficiency: Because AWD 
vehicles need bulkier and heavier components, they consume more fuel than RWD models, 
which tend to be much lighter.

Scene 10

7-A drive axle is a split axle with universal joints (UV joints) and a differential between the two 
half axles. It is a key component to a vehicle's drivetrain and refers to the axle or drive shafts of 
the vehicle's driving wheels.

Axle Assembly - This refers to the axle shafts that are found at the front of a FWD vehicle, and 
at the rear of an AWD car or SUV. They do not support any vehicle weight - they just transfer 
power from the engine to the wheel.

I n a nutshell the drive train component become more and more complex and need to be 
understood.,

28 (290, 21)
ABS Speed Sensor
and Wire Harness
C) Cotter Pin
117)
C Cotter Pin
110 (1,125, 81)
O Snap Ring
Drive Shaft
28 (290, 21)
13(130, 10)
8.0 71 h.lbf)
123 (1,250, 91)
Brake Caliper
Steering Knuckle
with Axle Hub
O Snap Ring
147 (1,500, 108)
Steering Knuckle Arm
Specified torque
C Non-reusable part
Precoated part

Arnault Ee

Page 1 (0s)

Page 2 (1m 10s)

Page 3 (2m 43s)

Page 4 (3m 47s)

Page 5 (3m 54s)

Page 6 (5m 9s)

Page 7 (7m 50s)

Page 8 (8m 41s)

Page 9 (9m 17s)

Page 10 (10m 29s)