Suspension MacPherson is one of the types of car suspension, in which the main element stands pillar shock absorber. It is still known in the people as a "swinging candle" or suspension on the guide racks. Initially, this design appeared as a result of the development of the suspension on the transverse double levers. In this case, from below only one transverse lever is installed, and in place of the second there comes a hinge that is high under the wing itself. In this device, the role of the lower arm part is generally performed by the anti-roll bar. The slope of the shock absorber strut for a car element like the McPherson suspension plays a crucial role. For the purpose of making corrections to the driving characteristics of the car, both longitudinal and transverse slopes are used.
The author of this suspension, created in the forties of the last century, is Earl McPherson, an American engineer, who at the time worked for the benefit of GM. The designer developed it for the Chevrolet Cadet, available for the working class car, which was to be sold on the American market. As a result, the model was never launched on the conveyor. In the end, the first large-scale car, which used a suspension type McPherson, in 1948 became Ford Vedet. It should be noted and the fact that in the very beginning of the twentieth century, the suspension was developed, practically not different in design from this. For example, Guido Fornasa of the Italian "Fiat" created in many respects a similar suspension several decades earlier, so there is an opinion that the American still borrowed these developments.
As originally planned by the engineer McPherson, the suspension could be used for both the front and rear wheels. This was also conceived for the Chevrolet Cadet project. Despite this, in the first cars the development was used exclusively from the front. In order to simplify the construction process and make it cheaper, the manufacturer decided to leave the rear suspension standard - dependent, on the longitudinal springs and with a rigid bridge. For the first time this installation was used for the rear wheels in the car Lotus Elite in 1957 by Colin Chapman. Proceeding from this, in some countries it is usually called Chapman's suspension. In our country, the name "swinging candle" or "candle suspension" is often used to refer to this development.
In its debut version, the McPherson suspension was distinguished by the fact that the ball joint in it was mounted on the continuation of the axis of the strut of the shock absorber. Consequently, the axis of the shock absorber was the axis of rotation of the wheel. After a while, there was a practice of shifting it outward, to the hinge wheel, so that the run-in arm got smaller values. This was done in the first generations of Volkswagen Passat and Audi 80. McPherson is noticeably inferior to the suspension on the transverse double levers in kinematic parameters. It takes up more space in height and transmits vibration more loudly to the body. Moreover, to perform the maintenance of the shock absorber it is necessary to remove the entire rack. There are also advantages: smaller cost, compactness in width and light weight, on the basis of what, the device has a wide popularity and in the modern construction of cars.
In the seventies of the last century, the McPherson suspension was widely spread. This can be explained by the fact that all the existing technological problems have been solved. In particular, we are talking about the possibility of serial production of shock absorber racks with the required resource. Now the device was cheap and highly technological, despite many shortcomings, so it was widely used in the automotive industry. In the eighties, this type of suspension was adopted even by the manufacturers of expensive cars, among them Mercedes-Benz, BMW and Audi. Despite this, some time later, such a need was lost, and leading car companies returned to the suspension on the transverse double levers. It though and is more expensive, but all the same has more qualitative kinematic parametres providing much the maximum comfort at driving.