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3.1 Activities completed
3.LI New magnetic valve
The development of a new kind of magnetic valve could be completed. The improvement with regard
to a constant response force of the damping device -independent from the movement velocities- is
shown in the following chart (Fig. 3.1). It is obvious, that the response force area of the 2 nd step device
is considerably increased compared to the previous device. The maximum response force already is
achieved at low movement velocities and it stays constant, i.e. independent from the movement
velocity. At a movement velocity of app. 10 mm/sec, the response force of the damper could be
increased from 29 kN to 700 kN by applying a current of 4,2 amperes and 22 volts. That means: with a
small amount of energy (less than 100 watts) we can control a power of 7,000 watts.
^ __ t ^possible response
force graph
velocity [mm/s]
Fig 3.1: comparison of adjustable damper force - 1 st and 2 nd design step of magnetic valves
The following picture (Fig. 3.2) shows the new designed piston with a special flow channel inside and
different adapted materials.
Fig. 3.2: Hydraulic piston with new magnetic valves