Pneumatic suspension is a form of suspension which allows to adjust the clearance (i.e. height of the bodywork relative to the road surface) by the pneumatic elastic elements.
Although the patents for air suspension were introduced in the early part of the twentieth century, the first attempts to create a successful design failed
It is used on trucks, semi-trailers, SUVs, and many business class models.
History and features of the pneumatic suspension design
The famous Citroen DS-19, which appeared in the market in 1955, became the first truly mass car with a pneumatic suspension. Although patents for air suspension appeared at the beginning of the 20th century, the first attempts to create a successful design and to implement it en masse were not successful. As far as Citroen's car, the adjustable piston marters have been installed on all of its wheels.
In 1957, there was a new model of the Cadillac Eldorado, also equipped with [ [ airstrip]] (unlike Citroen, which used telescopic piston springs).
The Mercedes-Benz 300 CE, which began sales in 1961, was also the same type as the Cadillac type. And it was this model that was the last of the cars that were fitted with a type of pneumosuspension. The interest in rubber coated shellings in the car suspension structure has been revived relatively recently when it is possible to combine it with electronic management systems.
Pneumosuspension device
The main resource required for the operation of this suspension type shall be air, within the regulated element-pneumors (or pneumatic control, as they are called). The elasticity of this structure is achieved by changes in the level of pressure and the amount of air within it. The necessary level of control is controlled by the control system, special electronics, sensors, valve system and air supply unit-compressor units, which drive the air into the elastic elements of the pneumatic actuators.
In addition, in addition to the air intake module, the air-suspension system is often fitted with a special compressors for the storage of the air, which is used at a low speed, so that it does not need to drive the air with the compressor.
All modern Pneumosuspension can be divided into three main types: one, two, and four
The accessor consists of a frame with a guide, a cuff, and a piston. A pneumatic elastic element may be constructed with either a built-in shock absorber or be separately installed. The cuff is made of a strong multilayer elastomer, or, in simple terms, from a reinforced rubber. In some cases, the residual pressure valves shall be mounted on the road to maintain pressure in the event of a leakage of air in the elastic element. In fact, the pneumatic suspension is not a separate vehicle suspension. This is because it is most often integrated into an already existing standard structure, be it a McPherson suspension, a "multi-houry" or a spring construction.
Type of air suspension
All modern Pneumosuspension can be divided into three main types: one, two, and four contour.
The single-contour pneumatic suspension is primarily for trucks and saddling tractors. It is placed on one axle (more often the rear) and adjusts its rigidity to the mass of the load in the car.
The two-contour may be installed on one axle and two. If fitted on one axle, it is responsible for independent regulation of both wheels, if on two, it acts as two single-circuit systems.
The four-contour (most complex) variety of the air suspension shall be adjusted separately. In most cases, the electronic control unit is present in the four-circuit systems, which, with the help of sensors, regulates the pressure in the actuators.
Current pneumatic suspension
In general, modern control systems simultaneously implement the three "Pneumos" algorithms. Firstly, force modification of the body level: in this case, the clenis and the rigidity of the vehicle suspension are manually adjusted by the driver manually through special regulatory devices. The "lowriders" (low-landing vehicles) are set up with a type of algorithm, which often excludes all of the other options set out below.
In the United States, there is a whole car culture focused on the use of pneumatic and hydraulic pendants in the development of cars and turning them into so-called "lowriders"
Secondly, automatic maintenance of the body level. In this case, it is a completely automatic adjustment of the clearance or stiffness of the suspension of the car by means of electronics that supports the specified level of the car body, regardless of its load.
Finally, third, automatic change of the body level depending on the speed of the car, which ensures the stability of the car in motion. When the speed set is set, the control program automatically decreases the clearance. When braking, the body of the vehicle is returned to its original position.
Today, controlled pneumatic signs are used by many leading automakers from the US, Europe and Japan, among them famous brands such as Audi, BMW, Volkswagen, Mercedes-Benz, Ford, GM, Land Rover, Lexus, Subaru and SsangYong. Among other things, there is a whole car culture in the United States, focused on the use of pneumatic and hydraulic jacks in the development of cars and turning them into so-called "lowriders"-"dancing" cars or literally "on the belly".
Pair suspension pros and cons
The main advantage of using pneumosuspension is that the car retains a splendid operation of the stroke, while not "cool" with the nose at the brake, does not roll in cool turns, at high speed it becomes more stable and keeps the road better.
Only the wear and tear of the rubber-mange-skin (especially when operating in Russia) and their high cost can be highlighted. In addition, the pneumatic suspension is very sensitive to operating conditions: its resource can dramatically reduce low temperatures or too "corrosive" road reagents.
