Learn More About Air Ride Suspension

Aug. 1, 2012 - PRLog -- Air-ride suspensions use bags of pressurized air to bear the weight of the vehicle. While they do help to make a vehicle more comfortable and versatile, they also have a few inherent drawbacks. These systems have seen a resurgence in popularity in recent years, due in no small part to the ingenuity of one company that few have ever heard of.

Purpose:

All suspensions have two basics jobs to do: to control wheel movement over road imperfections and to hold the vehicle's body off the ground. Air-ride (a.k.a. "airbag") suspensions accomplish both these tasks in the same way of any spring-based suspension. The air in the bags acts as a cushion in much the same way as the air in your tires does.

Benefits:

Air suspensions aren't inherently any better riding than spring suspensions; if you fill an airbag with 400 psi of pressure it will ride just as hard as a 400 psi spring. Airbags are, however, almost infinitely adjustable in terms of pressure between zero and the maximum pressure they can hold. For a softer ride, you let some of the air out to soften the bag.

Ride Hieght:

Airbags suspensions can do something else that spring-based suspensions cannot--they can raise and lower the vehicle at will. Increasing air pressure in the bags inflates them to a larger size, raising the vehicle farther from the ground. Lowering air pressure drops the vehicle closer to the ground. The ability to vary ride height at will has made airbag suspensions very popular with bus and motorcoach builders (since it allows the bus to drop for easier loading and unloading), and with the low-rider crowd, as a budget alternative to fully hydraulic suspensions.

Drawbacks:

The air ride suspension's most glaring drawback is that dropping the pressure will lower the vehicle, but it also makes the springs softer. This, when combined with the vehicle's already lowered stance, often results in bottoming out over the slightest bumps and potholes. Not only that, but soft springs do a poor job of controlling body motion, which makes the car handle like a barge. The inverse is also true; a tall ride height makes for a hard, bouncy and uncomfortable ride.

Solutions:

In the late 1990s, Bridgestone and Firestone got together to resurrect the air-ride suspension, forming a joint venture called Praxis to do so. All air suspensions use a piston to determine how much air gets displaced during suspension travel; a bigger piston means a stiffer spring and a smaller one means the opposite. Praxis incorporated into their 21st-century air-ride system a tapered piston assembly that's larger on the bottom than the top. This causes the airspring to get stiffer as it drops, which works well from both a performance and luxury perspective. Praxis's proprietary piston design (along with electronically adjustable shock absorbers) allows the end user to drop the car and reduce spring rate for performance driving, then raise the vehicle for a smooth and comfortable drive home. For more information, please visit: http://www.strutmasters.com/