912 : Divya .Kudalkar

930 : Sneha .Rao

961 : Riti . Gadagkar

964 : Soumya .Duddagi

EME Course Seminar

K.L.E. Society’s

B.V.B College of Engineering & TechnologyVidyanagar, Hubli – 31.

DIFFERENTIAL

Under the guidance of

Prof. Ramachandra L.

Step 1: Problem Definition

Need Statement:For the ease of turning.To reduce the strain on the axle components caused while turning.To overcome the slipping of tyres.

It should be light in weight

It should be a low cost technology

It should occupy less space

Less power consumption

Of moderate size so that it doesn’t affect the seating space in the automobile.

Design Criteria Set:

A differential is a device usually but not necessarily employing gears capable of transmitting torque and rotation through three shafts almost always used in one of two ways- in one way it receives one input and provides two outputs, this is found in most automobiles- and in the other way it combines two inputs to create an output that is sum, difference or average of the inputs.

In automobiles and other wheeled vehicles, the differential allows each of the driving road wheels to rotate at different speeds.

Step 2: Collect Pertinent Information

Step 3: Generate Multiple SolutionsA spool (or shaft) can be used to lock the wheels and run them at the same speed.A combination of gears can be used to make the wheels to rotate at different speeds.Fixing individual gears to each wheel so as to maintain different speed levelGear box mechanism can be used for each of the rear wheels which is inturn connected to a shaft

Spool

1. The wheels would have to be locked together, forced to spin at the same speed. This would make turning difficult and causes under steer.

2. During turning, one tire would have to slip. The force is required to make a tire slip causes heavy strain on the axle components.

Step 4 :Analyse and select a solution

A combination of gears This device has the capacity to split the engine torque into two ways , allowing each output to spin at different speeds. It prevents the unpredictable handling , damage to tyres and strain on the entire automobile and also prevents slipping of tyres .

Individual gearsIt may not best suit the automobiles as it is highly expensive, it consumes more power and it is too difficult to simultaneously control all the gears.

Contd...

Pointer MechanismIndividual gear box are fitted to each wheel which in turn is connected to a shaft that helps in shifting gears while in case of curve paths.. But the one disadvantage is that it may not shift properly and there may not be proper interlocking and alignment of gears during running.

Contd…

By analysing the above design solutions , the combination of gears is superior over the other solutions .

It transmits the power to the wheels while allowing them to rotate at different speeds (This is the one that earned the Differential its name.)

Step 5: Selection and implementation of solution

The differential is a device that splits the engine torque two ways, allowing each output to spin at a different speed.

DIFFERENTIAL

1. OPEN DIFFERENTIAL

2. LIMITED SLIP DIFFERENTIAL

3. LOCKING DIFFERENTIAL

TYPES OF DIFFERENTIAL

Construction

1. Side gears are mounted on the axle shafts.

2. Pinion gears are mounted on the ring gear.

3. Pinion gears are always in contact with the side gears.

4. Input pinion gear rotates the ring gear.

Construction

STRAIGHT PATH :

- The input pinion turns the ring gear and cage, and none of the pinions within the cage are rotating both side gears are effectively locked to the cage.

CURVED PATH :

-The side gears mounted on the axle shafts rotate at different speeds, accounting for the different velocities of the inner and outer wheels.

Working Principle

Criteria Weight (%)

Design1Spool

Design2Combination of gears

Design3Individual gears

Design4Pointer mechanism

EfficiencyR X Weight

25 4100

10250

8200

7175

SafetyR X Weight

20 7140

10200

7140

6120

DurabilityR X Weight

10 660

990

770

660

MaintenanceR X Weight

15 8120

9135

690

7105

CostR X Weight

15 9135

8120

460

7105

Less Power consumptionR X Weight

15 9135

9135

460

690

Total 100 690 930 620 655

DECISION MATRIX

THANK YOU