GROUP 1

CANOY | LACSON |MABAGA | MARIANO | SEDILLA | SILVA

 WHAT IS TRANSMISSION
SYSTEM?
A car transmission, often known as the

transmission system, is the mechanism that

transfers power from the engine to the driving

wheels. A transmission is mounted onto the

chassis of a vehicle in the front.

PARTS OF TRANSMISSION SYSTEM
1. CLUTCH
2. GEAR BOX
3. TRANSFER CASE
4. PROPELLER SHAFT AND UNIVERSAL JOINTS
5. FINAL DRIVE
6. DIFFERENTIAL
7. TORQUE TUBE
8. ROAD WHEEL
 GEAR BOX
It is composed of several pairs of gear wheels.

These transmit the available motion from the

crankshaft to the clutch at various rates. This

gives the engine and the road wheels the

necessary force. This force is adjustable to

cope with the different situations experienced

during vehicle movement.

 TRANSFER CASE
A transfer case is a component of four-wheel-

drive, all-wheel-drive, and other vehicles with

multiple powered axles. The transfer case uses

drive shafts to transmit power from the

transmission to the front and rear axles.

 PROPELLER SHAFT AND
UNIVERSAL JOINTS
It is responsible for transferring motion from

the gearbox to the differential.

 FINAL DRIVE
The final drive is a gear train that slows the

speed of the gearbox output shaft to adjust it

to the traction wheels; it is sometimes

combined with a differential mechanism.

 DIFFERENTIAL
The transmission system must turn the motion

through 90 degrees because the axes of the

propeller shaft and live axle are at a right angle

to each other. The differential performs this

through a wheel and pinion arrangement. Another

function of the differential is to vary the speeds

of the inner and outer wheels when the vehicle is

turning.
 TORQUE TUBE
The torque tube is made up of a large diameter

stationary housing between the transmission and

the rear end that completely completely covers a

rotating tubular steel or small-diameter solid

drive shaft that transmits engine power to a

regular or limited-slip differential.

 Types of
Transmission
 MANUAL TRANSMISSION
The driver must manually choose and engage the gear ratios with
this sort of transmission system.

PARTS OF A MANUAL TRANSMISSION​

1. Flywheel​
2. Clutch Disc​
3. Clutch Pedal​
4. Clutch Shaft / Input Shaft ​
5. Counter Shaft / Layshaft ​
6. Main Shaft / Output Shaft​
7. 1st-5th gears ​
8. Idler gear ​
9. Synchronizer
FLYWHEEL
A heavy wheel attached to a rotating shaft so as to smooth out delivery of power from a motor to a
machine. It is a circular component that transmits engine torque to the clutch disc.

CLUTCH DISK
The clutch disc aids in torque transfer from the engine to the manual transmission system. The clutch
pedal is used by the driver to control the disc.

CLUTCH PEDAL 
It allows for the clutch to be disengaged by pressing on the clutch pedal with your foot​

INPUT SHAFT 
The input shaft comes from the engine. This spins at the same speed and power of the engine. Also
called Clutch Shaft or Driving Shaft ​
COUNTER SHAFT
The countershaft (also known as the layshaft) is located beneath the output shafts. A fixed
speed gear connects the countershaft to the input shaft directly. The countershaft spins at
the same speed as the input shaft whenever the input shaft rotates.

MAIN/OUTPUT SHAFT
The output shaft runs parallel above the countershaft. This is the shaft that delivers power to the
rest of the drivetrain. The speed of the output shaft is determined by which of the five gears are
in “gear,” or engaged.​

1st-5th GEARS
These are the gears that are supported by bearings on the output shaft and decide
the "gear" your vehicle is in. Every one of these gears is constantly entangled with one
of the countershaft's gears and spinning. The first gear is the largest, and the gears get
smaller as you approach closer to fifth gear. ​
IDLER GEAR
The idler gear (sometimes known as the "reverse idler gear") is
located between the output shaft's reverse gear and a countershaft
gear. Your car's idler gear is what allows it to reverse. ​

SYNCHRONIZER
It matches the speed of the gears running with the speed of the engine
to the hubs running at the speed of the output shaft for a smooth
shifting of gears.​
STAGES
ADVANTAGES AND DISADVANTAGES
ADVANTAGES
Easier to maintain
Affordable
Effiicient
More control
Cheaper
ADVANTAGES AND DISADVANTAGES
DISADVANTAGES
Learning curve
Difficulty on hills
Pain from the clutch
Less comfort
Expensive
 Automatic Transmission
Under normal driving circumstances,
an automatic transmission (often
shortened to auto or AT) is a multi-
speed gearbox used in automobiles
that does not require any driver
input to change forward gears. It is
formally referred to as a transaxle
since it combines a transmission,
axle, and differential into one
integrated system.
Parts of an Automatic Transmission

Torque Converter

The torque converter is what

permits or inhibits power from
the engine from being passed to
the gearbox, as well as what
multiplies torque to start the
automobile moving from a
standstill.
Planetary Gears

Planetary gears are

commonly utilized as
speed reducers. They are
used to boost the torque
and slow down motors.
Components of a Planetary Gear

1. Sun Gear
2. Planet Gear
3. Carrier
4. Ring Gear
Sun Gear
Sits at the center of the
planetary gear set

Ring Gear
The outer gear, the ring
gear, contains internal
teeth. The ring gear is in
continuous mesh with the
planet gears and surrounds
the remainder of the gear
set.
PLANET GEARS / PINIONS AND THEIR CARRIER

Three or four smaller gears

that round the sun gear and
are always in contact with it.
Each planet gear rotates on
its own shaft, which is
attached to the carrier.
Planet gears not only
revolve around the sun gear,
but they also orbit it.
Brake Bands
The brake bands can be
tightened to keep the ring or
sun gear motionless, or they
can be relaxed to allow the ring
or sun gear to rotate. A
hydraulic system controls
whether a brake band tightens
or loosens.
Clutches
A planetary gear system's
many elements are
additionally connected by a
series of clutches. Automatic
transmission clutches are
constructed up of a number
of metal and friction discs
(hence the name "multi disc
clutch assembly").
 DIFFERENT TYPES OF
AUTOMATIC TRANSMISSION
 Dual Clutch Transmission (DCT)

This form of automatic transmission

is popular with semi-automatic cars
due to the speed and smoothness of
gear changes. The even gears will be
controlled by one automatic clutch,
while the odd gears will be controlled
by the other. The use of two clutches
allows for a significantly smoother,
and often unnoticed, transmission.
 How does DCT works
A DCT features two clutches:
one that handles the odd-
numbered gears and one that
handles the even- numbered
gears. The two clutches operate
independently, and there is no
clutch pedal needed.
Semi Automatic Transmission

The majority of semi-automatic

transmissions are based on traditional
manual transmissions, but they're frequently
controlled by an automatic clutch or another
type of partially automated transmission
system. The transmission becomes semi-
automatic after the clutch is automated.
However, these systems still require the driver
to pick gears manually. A clutch less manual
or automated manual transmission is the
name given to this type of transmission.
How Does Semi-Automatic Transmission Works
Semi-automatic vehicles are an excellent way for new and experienced drivers to learn how to
shift gears. Semi-automatics, unlike manual transmission cars, do not have a clutch pedal,
making them easier to operate. When it's time to change the car's mode or gear, all you have to
do is pull the lever. This is accomplished by listening to the car's engine.

For a semi-automatic gearbox, you’re likely to see the letters P, R, N, D & M or A, N, R & M.
P = Park​
R = Reverse​
N = Neutral​

M = Manual​
D = Drive​
A = Automatic​
 Pros and Cons of Semi-Automatic Transmission
Pros
The driving experience is very smooth when shifting gears.
If the torque converters experience slippage, there won’t be any loss of energy.
You won’t experience this loss during manual shifts either.
Cons
Requires more money to maintain a semi-automatic than it does for manual.
Repairing a semi-automatic is expensive. Replacement would actually be
cheaper.
Semi-automatics have a history of malfunctioning and failing. There are lots
of reasons why this could happen and they may not even involve the
transmission directly.
What is CVT?
Continous Variable Transmission
seamlessly changes through an unending
range of effective gear ratios while you
drive.
also known as single-speed, shiftless, and
stepless transmissions.
CVT's COMPONENTS
Clutches

Pulleys

Shaft

Belt or Chain

Hydrostatic pumps

Hydrostatic motors
Microprocessor and sensors
Clutches
1. Primary clutch
An advanced form of centrifugal clutch and is typically
mounted to the output end of the engine crankshaft.
The clutch has two sheave faces; one that is laterally
fixed (stationary sheave), and one that can move in and
out to engage the belt (moveable sheave).
2. Secondary clutch
It is mounted to the input shaft of the transmission,
transaxle, or the like.
In modern CVT systems such as those used in
recreational vehicles, the secondary clutch has two
functions: as a “slave” to the primary clutch and to provide
a torque sensing element.
Pulleys
a variable input pulley which spins from the
power provided from the engine.

an output pulley that sends the power to

the driven wheels.
Shaft
1. Input shaft
The power source for this input shaft
is engine which means continuously
variable transmission gets the input
from the engine through input shaft.
2. Output shaft
Output shaft is responsible to transmit
final output power to the final drive of
the vehicle.
Hydrostatic pumps
It is used in hydraulic systems that
work via positive displacement.
Positive displacement involves the
process of trapping of a fluid and then
displacing, or forcing, it through a
controlled channel.
Hydrostatic motors
Transform fluid energy into rotary
mechanical power, which typically
is applied to a load via shaft.
Microprocessor and sensors
For the transmission to be able to
detect the driving conditions.
ADVANTAGES OF CVT
SMALL POWER LOSS PRECISION TORQUE

There is a low power loss It provides smooth, step-less Delivers maximum ideal
experienced which resulted gear changes. torque.
in enhanced acceleration.

DESIGN EFFICACY COMFORT

Simple structure and light This increases fuel efficiency Allows for a better ride by
weight. and lowers pollution. adapting to changing road
conditions and power needs.
DISADVANTAGES OF CVT
COST STRENEOUSITY CLATTERS

Higher cost in maintenance Friction-based motion Produces extra noise.

and repair transmission wears down
faster.

SPECIFITY TREMULOUS

Necessitates the use of

At low speeds, it becomes
specialized oil and other
jerky in car applications.
components.
REFERENCES
Carsblog.(n.d.). CVT and its Advantages and Disadvantages. Retrieved April 06, 2022,
from https://www.dubizzle.com/blog/cars/cvt-transmission-pros-cons/

Harris, W. (2005, April 27). How cvts work. HowStuffWorks. Retrieved April 9, 2022, from
https://auto.howstuffworks.com/cvt.htm?fbclid=IwAR0XzGhFpjWVt83TzuVCVLn--
mMW1fcR9ixiOOIj9aZeGUyB9pm4U8WeJ2o

Research, H. A. (2021, November 29). What is a CVT transmission? Car and Driver.
Retrieved April 9, 2022, from
https://www.caranddriver.com/research/a30822055/what-is-a-cvt-transmission/

Nice, K. (2000, November 29). How automatic transmissions work. HowStuffWorks.

Retrieved April 23, 2022, from https://auto.howstuffworks.com/automatic-
transmission.html
Nera, J. (2021, Mar 26). What is a DCT or Dual-Clutch Transmission. Retrieved April 23, 2022,
from https://www.jdpower.com/cars/shopping-guides/what-is-a-dct-or-dual-clutch-
transmission

Stevens, M. (2021, June 30). Semi-Automatic Transmission (How it Works and Pros/Cons).
Retrieved April 23, 2022, from https://cartreatments.com/semi-automatic-transmission-
overview/