This document provides an overview of continuously variable transmissions (CVTs). It discusses the history of CVTs, how they work using a belt-pulley system to provide infinite gear ratios, and their advantages like improved fuel efficiency. The document also outlines different types of CVTs, applications, and the current market share of various transmission types. CVTs are becoming more common in small cars and SUVs due to their improved performance and efficiency compared to traditional automatic transmissions.

1. Continuously Variable
Transmission
By- Rishabh Nishad
ME-IIIrd Year
Sec-B
1502931123
Under Guidance Of
Mr. Sumeet Dubey
Asst. Professor
ME Department

2. Index:-
1. Transmission and it’s type’s.
2. History of CVT.
3. CVT-Construction and Working.
4. Advantages and Disadvantages.
5. Types Of CVT.
6. Applications.
7. Market Share of different Transmission’s
8. Refrences.

3.  Transmission:-
 What is Transmission in Vehicles?
 Types of Transmission:-
1. Manual Transmission.(MT)
2. Automatic Transmission.(AT)
3. Dual-Clutch Transmission.(DCT)
4. Automatic Manual/Clutchless Manual Transmission.(AMT)
5. Continuously Variable Transmission.(CVT)

4.  History Of CVT:-
 First Conceptualized by Leonardo Da Vinci in 1490.
 First patent of CVT Transmission was made by Daimler & Benz in 1886.
 In 1910 Zenith motorcycles built a V2 motorbike that was so successful
in hill climb events that it was banned from the events to give other
motorcyclists a chance at competing.
 In the late 1980’s Subaru launched a car called Justy which was the
first car in USA to offer the CVT Transmission.

5.  CVT:-
 CVT is a type of Automatic Transmission used in Automobiles. Unlike
other transmissions CVT’s don’t have a gear box or any type of gear
arrangement. The most common type of CVT operates on an Belt-
Pulley system which allows infinite number of gear ratios.
 Construction:-
 Contrary to other complex transmissions a CVT have only three
basic components:
1. A metal or rubber belt.
2. A variable-input "driving" pulley.
3. A variable output "driven" pulley.

6.  Working:-
 When one pulley increases it’s radius the other decreases it’s
radius to keep the belt tight.
 When the pitch radius is small on the driving pulley and large on
the driven pulley it results in lower gear and decrease in speed.
 When the pitch radius is large on the driving pulley and small on
the driven pulley it results in higher gear and increase in speed.

7.  Advantages:-
I. Engine holds one revolution range, typically the one that delivers
the most efficiency, most power, or most torque and only gear
ratio changes.
II. The result is a smoother, more fuel efficient and quicker drive
than an normal automatic.
 Disadvantages:-
I. Energy losses due to friction are greater with a CVT.
II. Experience of car driving Is not so good because of set revolution
range of engine.
III. Traditional, belt-drive CVTs can handle limited amount of torque.
CVTs are often found in small cars and SUVs like Audi A4, Nissan’s
new Pathfinder etc.

8.  Types Of CVT’s:-
I. Toroidal CVTs:- It replaces the belts and pulleys with discs and
power rollers.
II. Hydrostatic CVTs:-It’s non-frictional. The pump and motors are
used to converts fluid flow into rotational motion and vice-versa.

9.  Advancements:-
 One of the most important advances has development of metal
belts to connect the pulleys. These flexible belts are composed of
several thin bands of steel that hold together high-strength, bow-
tie-shaped pieces of metal.
 Metal belts don't slip and are highly durable which enables CVTs to
handle more engine torque. They are also quieter than rubber belt
driven CVTs.

10.  Market Scenario :-
 Manual Transmission (MT) have the largest market share of more
than 50%. Followed by Automatic Transmission (AT)>CVT>Dual
Clutch Transmission (DCT)> Automatic Manual Transmission (AMT).

11. THANK YOU