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A New Self-Energizing Levelling System
Published July 02, 1997 by Associazione Tecnica Dell'Automobile in Italy
As car makers increasingly try to cut fuel consumption by reducing vehicle weight while at the same time leaving room for at least four people and their luggage, optimizing a chassis with conventional suspension and shock absorbers becomes more and more difficult.
When a small empty vehicle is loaded, the weight on the rear axle in particular may increase by over 120%. Expecting a vehicle to take more than double the weight it had when it was empty means forcing spring rates, suspension travel and shock absorber characteristics into compromises which are increasingly out of the line with modern standards of comfort and driving stability.
But people are not prepared to compromise to any extent on the comfort, let alone driving safety they are used to. So the problems involved in optimizing the suspension are obvious.
The static suspension travel required between empty and full load in itself is lost in one direction, seriously compromising driving performance.
In view of all the factors involved, a level control is called for which uses no energy in the form of fuel or electric power but is able to adjust the suspension and shock absorber characteristics to the extreme differences in weight involved.
It should weigh in at much less than an air suspension with compressor, air drier, valve block, height control, shock absorbers and air belts. It should also be small enough to leave enough space between the axle and the bodywork which, as we know, is relatively limited.
All the demands regarding function, packaging, weight and costs are met by a system which utilizes the kinetic energy from the wheels, this new self-energizing levelling system.