Functions of the Differential

 

Differential Unit

Any vehicle that makes use of a set of wheels on each side, that is, one facing the other, has a problem of maintaining harmonized speed when negotiating a corner. It is for this reason that a mediating device is required. Whatsoever the device will look like or whatsoever principle of operation it will make use of, it must be capable of harmonizing the speed of the outer and the inner wheels when the vehicle is negotiating a corner. This device is called the Differential.

The differential unit of the motor vehicle is one of the major components of the transmission trains. This gear train is made of three independent shafts of which two of the (driven) shafts are connected at angular distances to the (driving) input shaft coming directly from the universal joint.

This transmission component brings to bear its major role when the vehicle is negotiating a corner; it works by harmonizing the speed of the inner and outer rotating wheels. That is, the speed of the outer wheel will be increased so it can be in union with the inner wheel which has a relatively shorter distance to cover. Here, the Differential is simply permitting the road wheels to work at different RPM (revolution per minute), while maintaining balance and stability of the vehicle.

The location of the differentials varies depending on the drive of the vehicle. For example, in front wheel drive, the differentials is contained in the same casing as the gear box. In rear wheel drive, it is located at the rear of the vehicle in between the tail end of the propeller shaft and the two half shafts which are connected to the road wheels.

The Differential comes with other names which are often used interchangeably by many people; these include final drive and torque equalizer.

Specific functions of the Differential

1. To transmit the drive through right angle from propeller shaft to the axle half shafts. 
2. To provide a means of supporting the differentials. 
3. To give a permanent speed reduction thereby providing further torque increase to the road wheels. 

Generally, the differential unit allows one of the driving wheels to turn faster than the other when the vehicle is cornering, but at the same time maintain equal torque.