The Differential Gearbox

1.     INTRODUCTION

A differential gearbox is a device used to distribute power from a drive shaft to two wheels or axles. It allows each wheel or axle to rotate at different speeds, which is necessary for smooth turns and improved traction. The differential gearbox helps equalize the torque applied to the wheels, so one wheel doesn't slip while the other spins. This enhances the vehicle's stability and handling.

 

2.     FUNCTIONS OF DIFFERENTIAL GEARBOX

The main functions of a differential gearbox are as follows:-

1) Distributing torque evenly to both drive wheels:-

It means dividing the engine's rotational force (torque) equally between the two drive wheels. This allows both wheels to receive the same amount of power and provides better traction, stability, and control to the vehicle. When a vehicle turns, the inside wheel has to travel a shorter distance than the outside wheel, causing the inside wheel to rotate slower. The differential gearbox allows for this difference in rotational speed by distributing torque equally to both wheels, ensuring that the vehicle continues to move forward smoothly and without any loss of traction.

 

2) Allowing wheels to rotate at different speeds during turns:-

When a vehicle makes a turn, the inside wheel has to travel a shorter distance than the outside wheel. This difference in the distance traveled by each wheel means that the inside wheel rotates at a slower speed than the outside wheel.

Allowing wheels to rotate at different speeds during turns means that the differential gearbox enables the wheels to rotate at different speeds, compensating for the difference in their distances traveled. This allows the vehicle to turn smoothly without any binding, slipping, or loss of traction.

 

3)Transfers power from the drive shaft to the axle shafts:-

Transfers power from the drive shaft to the axle shafts means that the differential gearbox is responsible for transmitting the power generated by the engine to the wheels that drive the vehicle.

In a typical drivetrain, the engine produces a torque which is then transferred to the drive shaft. The differential gearbox is located between the drive shaft and the axle shafts, and its main function is to receive the torque from the drive shaft and distribute it to the two axle shafts.

Each axle shaft is connected to a wheel and transfers the torque to the wheel, providing the power needed to drive the vehicle. The differential gearbox helps to evenly distribute the torque to both wheels, ensuring that the vehicle moves forward smoothly and without any loss of power or traction.

 

4) Reducing wheel slippage on slippery surfaces:-

Reducing wheel slippage on slippery surfaces refers to the ability of the differential gearbox to reduce the likelihood of the wheels losing traction on surfaces with low friction, such as wet roads or ice.

When a vehicle is driving on a slippery surface, the wheels can lose traction and start to slip. This can cause the vehicle to lose control and skid. The differential gearbox can help to reduce wheel slippage by distributing torque evenly to both drive wheels.

When the wheels receive equal amounts of torque, it helps to maintain traction and stability, reducing the likelihood of slipping or losing control on slippery surfaces. Additionally, some differential gearboxes, such as limited-slip differentials, use special mechanisms to apply additional torque to the wheel with the most traction, further reducing the risk of wheel slippage.

 

3.     NEED OF DIFFERENTIAL GEARBOX

The need for a differential gearbox arises from the requirement to transmit the engine's power to the wheels while allowing each wheel to rotate at different speeds. The main reasons for having a differential gearbox include:

1.     Improved traction: The differential allows both drive wheels to receive equal amounts of torque, providing better traction, stability, and control to the vehicle.

2.     Smooth turning: When a vehicle turns, the inside wheel has to travel a shorter distance than the outside wheel. The differential enables the wheels to rotate at different speeds, compensating for the difference in their distances traveled, allowing the vehicle to turn smoothly.

3.     Reduced wheel slippage: The differential helps to reduce wheel slippage by distributing torque evenly to both drive wheels, ensuring that the vehicle moves forward smoothly on slippery surfaces.

4.     Efficient power transfer: The differential receives the torque from the drive shaft and distributes it to the two axle shafts, providing the power needed to drive the vehicle efficiently.

Overall, the differential gearbox is an essential component in a vehicle's drivetrain, allowing the engine's power to be transmitted to the wheels while providing improved traction, stability, and control.

 

5.     PRINCIPLE OF DIFFERENTIAL

The principle of a differential gearbox is based on the concept of equal and opposite forces. The differential gearbox uses gears and bearings to transfer torque from the drive shaft to the two axle shafts while allowing each axle shaft to rotate at different speeds.

When a vehicle turns, the inside wheel has to travel a shorter distance than the outside wheel. The differential gearbox allows the wheels to rotate at different speeds by using gears and bearings to transfer torque from the drive shaft to the two axle shafts.

The differential gearbox contains two bevel gears that are arranged in a cross configuration, with the drive shaft attached to one gear and the two axle shafts attached to the other two gears. The bevel gears mesh with each other, allowing torque to be transferred from the drive shaft to the axle shafts.

As the wheels turn, the bevel gears rotate, transmitting torque to the axle shafts. The torque is then transferred from the axle shafts to the wheels, providing the power needed to drive the vehicle. Because the inside wheel has to travel a shorter distance than the outside wheel, the differential gearbox allows each axle shaft to rotate at a different speed, compensating for the difference in the distance traveled by each wheel and allowing the vehicle to turn smoothly.

In summary, the principle of a differential gearbox is to use gears and bearings to transfer torque from the drive shaft to the two axle shafts, while allowing each axle shaft to rotate at a different speed, ensuring that the vehicle can turn smoothly and efficiently.

 

6.     DIFFERENTIAL GEARBOX DETAIL DIAGRAM

 

7.     CONSTRUCTION

The major components of a differential gearbox are:

 

a)    Bevel gears: Two bevel gears are arranged in a cross configuration to mesh with each other, allowing torque to be transferred from the drive shaft to the axle shafts.

 

 b)    Drive Pinion: The drive pinion is a small gear that meshes with the ring gear and transfers torque from the drive shaft to the differential gears.

c)     Ring gear: The ring gear is a large gear that surrounds the differential gears and receives torque from the drive pinion.

 

 

d)    Axle shafts: The axle shafts are connected to the wheels and transfer torque from the differential gears to the wheels.

e)     Bearings: Bearings are used to support and reduce friction in the differential gears, allowing them to rotate smoothly and efficiently.

 

f)      Side Gears: The side gears are attached to the axle shafts and receive torque from the differential gears.

g)    Spider gears: The spider gears are the small gears that are located in the center of the differential and mesh with the side gears, allowing the axle shafts to rotate at different speeds.

The key parts of a differential gearbox, which allow each wheel to rotate at a distinct speed, are, in summary, bevel gears, driving pinion, ring gear, axle shafts, bearings, side gears, and spider gears. These parts work together to deliver torque from the drive shaft to the wheels.

 

8.     WORKING OF DIFFERENTIAL GEARBOX

The differential gearbox works by using gears and bearings to transfer torque from the drive shaft to the two axle shafts while allowing each axle shaft to rotate at different speeds. The main components of a differential gearbox are the bevel gears, drive pinion, ring gear, axle shafts, bearings, side gears, and spider gears.

1.     The drive shaft is attached to the drive pinion, which is a small gear that meshes with the ring gear. The ring gear is a large gear that surrounds the differential gears and receives torque from the drive pinion.

2.     The bevel gears are arranged in a cross configuration and mesh with each other, allowing torque to be transferred from the drive shaft to the axle shafts. The side gears are attached to the axle shafts and receive torque from the differential gears.

3.     The spider gears are the small gears located in the center of the differential and mesh with the side gears, allowing the axle shafts to rotate at different speeds. . The differential allows the wheels to rotate at different speeds by using the spider gears to transfer torque to the axle shafts.

4.     The bearings are used to support and reduce friction in the differential gears, allowing them to rotate smoothly and efficiently.

5.     The differential gearbox continuously monitors the speed of each wheel and adjusts the torque distribution accordingly, ensuring that both drive wheels receive equal amounts of torque, providing improved traction, stability, and control to the vehicle.

 The differential gearbox works by using gears and bearings to transfer torque from the drive shaft to axle shafts, while allowing each axle shaft to rotate at different speeds, ensuring that the vehicle can turn smoothly and efficiently.

 

9.     TYPES OF DIFFERENTIAL GEARBOX

There are several types of differential gearboxes, each with its unique features and applications:

1.     Open differential: An open differential distributes torque evenly to both wheels, allowing them to rotate at different speeds. When one wheel loses traction, the open differential diverts torque to the other wheel, reducing wheel slippage on slippery surfaces.

2.     A limited-slip differential (LSD): A limited-slip differential (LSD) is similar to an open differential, but with a clutch mechanism that provides a limited amount of torque to the wheel with less traction. This provides improved traction compared to an open differential, especially on slippery surfaces.

3.     Locking differential: A locking differential uses a locking mechanism to force both wheels to rotate at the same speed, providing maximum traction in difficult off-road conditions. This type of differential is often used in four-wheel drive vehicles.

4.     Torsen differential: A Torsen differential uses worm gears to distribute torque between the wheels. It automatically sends more torque to the wheel with better traction and less torque to the wheel with less traction, providing improved traction and handling.

5.     Electronic differential: An electronic differential uses sensors and electronic controls to monitor the speed of each wheel and adjust the torque distribution accordingly. This type of differential can provide improved traction and handling, especially in high-performance vehicles.

6.     Epicyclic differential: An epicyclic differential uses planetary gears to transfer torque between the wheels. This type of differential is often used in front-wheel drive vehicles, where the differential is integrated into the transaxle assembly.

In summary, there are several types of differential gearboxes, including open differential, a limited-slip differential (LSD), locking differential, Torsen differential, electronic differential, and epicyclic differential, each with its unique features and applications.

 

10.  SEVERAL ADVANTAGES OF A VEHICLE WITH A DIFFERENTIAL GEARBOX

 

1.     Improved Traction: By distributing torque evenly to both drive wheels, the differential gearbox helps to reduce wheel slippage on slippery surfaces, providing improved traction and stability.

2.     Better Handling: The differential gearbox allows the wheels to rotate at different speeds during turns, providing improved handling and maneuverability.

3.     Increased Efficiency: The differential gearbox allows the wheels to rotate at different speeds, reducing friction and wear on the drive train components, and providing increased efficiency and longer component life.

4.     Enhanced Performance: The differential gearbox provides improved traction, stability, and handling, allowing the vehicle to perform better and respond more effectively to changes in road conditions.

5.     Increased Safety: The differential gearbox helps to reduce wheel slippage on slippery surfaces, providing improved traction and stability, which enhances the overall safety of the vehicle.

6.     Better Power Delivery: The differential gearbox transfers power from the drive shaft to the axle shafts, providing more efficient power delivery to the wheels, resulting in improved performance and fuel efficiency.

From this, we conclude that the differential gearbox provides several advantages in a vehicle, including improved traction, better handling, increased efficiency, enhanced performance, increased safety, and better power delivery.

 

Institute and Group details are as follows:-

Bansilal Ramnath Agarwal Charitable Trust’s

Vishwakarma Institute of Technology

(An Autonomous Institute affiliated to Savitribai Phule Pune University formerly University of Pune)

 

Academic Year:-  2022 – 2023

Department:- Mechanical Engineering

Class:- SEDA

Batch:- 02

Group No.:- 04

Subject:- Analysis And Simulation Of Machines And Mechanisms 

GROUP DETAILS:-

SR. NO.	NAME OF THE STUDENT	ROLL NO.	PRN NO.
1	Pooja Rajendra Lahare	43	12220138
2	Lavkesh Jagadish salunke	44	12220211
3	Varad Anand Lomte	45	12220179
4	Yash Balasaheb Mali	46	12220205
5	Nishiraj Nitin Mane	47	12220010
6	Kaustubh Vinod Palande	54	12220132