DELPHI and the shock absorbers. History of de Carbon.
1953: The high-pressure monotube shock absorber was invented by Christian Bourcier de Carbon. Set up of the De Carbon company.
1961: Acquisition of Argenteuil factory for the shock absorbers' mass production for Renault 4.
1966: Acquisition of Ande factory.
1971: The floating monovalve piston was patented.
1978: Expansion of the Ande factory.
1988: De Carbon becomes 60 % owned by DELPHI.
1995: Construction of a new factory in Dayton ( USA ) for the production of monotube shock absorbers.
1997: De Carbon becomes 100 % DELPHI.
Certifications O. E. ( Original Equipment )
QS 9000 (De Carbon Andå)
ISO 9001 (De Carbon Andå)
EAQF (Renault Certification): A92 ( De Carbon Ande - January 1996 - This certification is recognized by PSA group as well as by the German and Italian manufacturers ).
ISO 9001 (DELPHI Chassis - Cadiz - Spain).
ISO 9001 (DELPHI Automotive Systems - Paris-Villepinte Technical Centre).
According to the definition, suspension of the vehicle is a compromise between comfort of the passengers and stability of the vehicle ( tyre contact to the road under any circumstances ).
There are three types of shock absorbers:
- The hydraulic twintube ( conceived by Newton in 1912 ).
- The hydraulic low-pressure twintube ( introduced in 1920 ).
- The high-pressure monotube ( patented by Christian Bourcier de Carbon in 1953 ).
Twintube hydraulic shock absorber
The gas charged twintube shock absorber
Features and advantages of the twintube shock absorbers:
Piston rod hardened by induction and highly polished.
Various additives added to the oil in order to provide it with the qualities required to obtain the best performance.
Does not overheat in severe conditions ( because it looses part of its efficiency ).
Reservoir tube protects the cylinder from external damages by stones, sand etc.
Better supports the lateral efforts. Reduced friction, which improves the comfort.
The unique high-pressure monotube system of De Carbon
The double action floating valve
Thanks to the double action floating valve only de Carbon monotube shock absorber offers a perfect and instant damping under all conditions.
Function and working of the high-pressure monotube system of Delphi de Carbon
On an even road surface the shock absorber works at the oil area - the passengers obtain maximum comfort. When the road surface is more uneven the gas area under high-pressure starts working - the suspension becomes hard enough in order to guarantee maximum stability. At the same time the opening of the double action floating valve keeps up a real comfort.
Delphi de Carbon - maximum comfort and stability
Drawing, which is showing the dependence between damping and frequency of the piston rod"s movement ( the ability of the shock absorber to support comfort and stability when the road is getting more and more uneven ).
ADVANTAGES of the high-pressure gas monotube De Carbon:
Better precision setting and weak dispersion in production.
Will operate in any position.
Oil and Gas cannot mix. Efficiency maintained
Smaller diameter and weight for a given application.
Instant response thanks to the de Carbon floating piston design.
Better heat dissipation: increased life.
No emulsion, physical separation between oil and gas.