Air suspension

I shared about suspension a little while back you can check that post here. Today I will discuss about Air suspension. So let us see what is Air suspension and how does it work.

What is Air Suspension?

Air suspension is a type of vehicle suspension powered by an electric or engine-driven air pump or compressor. This compressor pumps the air into a flexible bellows, usually made from textile-reinforced rubber. The air pressure inflates the bellows, and raises the chassis from the axle.

So what is the difference between traditional suspension and air suspension. The basic difference is we are replacing steel springs and leaf springs with air bags/springs these are rubber membrane which holds pressurized air on which your vehicle is riding on. Traditional suspension has a damper mechanism set to a certain ride control, while air suspension system uses air compressor with the shock absorbers to maintain the ride control.

How Air Suspension Works?

COMPONENTS-OF-AIR-SUSPENSION

There is a frame in which the air line runs through and it connects all the air bags. Air pump supplies air to the air bags and maintains the air pressure according to the need. The control unit is the brain of this system which senses everything and manages the air supply and also the ride height using height sensors. The drier is used to remove any moisture in the air which is sucked from the atmosphere. Height sensor maintains the ride height to the level which you have adjusted using the controls.

Consider a situation where you have a truck (Dodge RAM) it has air suspension. There are mostly three levels in which we can adjust the ride height. High for off-road where you get maximum ground clearance. Medium for daily driving where you’re driving in normal roads. Low for high-speed driving which will have minimum air resistance. It also adjusts the ride height even if you add more weight, for example if you increase the load in the rear normal vehicle will lean back, but the air suspension will sense it and level the ride height.

Types of Air Suspension

Convoluted Air Spring

convoluted air springsRolling Lobe Air Spring

rolling lobe air springThere two systems in air suspension which are used to pull air from environment

Open System

In this system the air is sucked via air supply unit and sent to reservoir and then to the air springs. Here reservoir is used to have a control over the air supply to the air springs. When air spring wants to release pressure, it just releases the air to the atmosphere. That’s the hissing sound you here in the vehicles having air suspension. They release air when come to a stop to lower the ride height.

Closed System

This system also works the same way, but it does not release air to the atmosphere instead sends back to the reservoir which can be sent again back to the air springs. This is a better system because it has quick response time, more efficient and does make the hissing sound every time the air is released.

Advantages and Disadvantages

  • You adjust the ride height of your vehicles
  • Getting in and out of the tall vehicles is easy, as you can adjust the height
  • Customizable according to the condition of the driving
  • Adjust the ride height automatically for lower air resistance while driving on a highway for better fuel economy
  • Load leveling which is discussed above
  • It also increases the ride quality and hence it is used in high-end cars like Rolls Royce Bentley.
  • There is only one disadvantage which is the cost, this system gets expensive with all the options.

So Air suspension are good but you need to consider the cost which is high. If you don’t want a versatile vehicle, means you use one vehicle for all the purpose then spending extra for this suspension is not worth. If you add on from aftermarket it is expensive and also repairing this system can be complex and expensive


Also published on Medium.