CONTENTSVIBRATION ISOLATION : WHY ? HOW TO MODEL THE PROBLEM ? WHAT IS RESONANCE ? WHAT TO USE ? HOW TO CHOOSE A SPRING ?
WHY ?VIBRATIONS CAN BE A PROBLEM FOR :-THE MACHINE ITSELF-THE ENVIRONMENTTO MINIMIZE THE PROBLEM OF VIBRATIONS :DESIGN OF A VIBRATION ISOLATION SYSTEM
HOW TO MODEL THE PROBLEM ? ACTIVE ISOLATION : F FT OR PASSIVE ISOLATION : X
WHAT IS RESONANCE ?RESONANCE : tendency of a system tooscillate with larger amplitude at somefrequencies than at others. RESONANT FREQUENCIES
WHAT TO USE ? dampers spring boxes aircushionsEvery isolation system canbemodeled by a spring and a damper. Here, wewillconsideronly the spring constant.
HOW TO CHOOSE A SPRING ? COMPARISON BETWEEN :- F : FREQUENCY OF THE STRUCTURE- FO : RESONANT FREQUENCY OF THESPRINGIF F > FO : AMPLIFICATION OFTHE VIBRATIONSIF F = FO : RESONANCEIF F > FO : ABSORPTION OFVIBRATIONS IF F > 4 FO : T < 0,1
CONCLUSION TO DESIGN A VIBRATION ISOLATION SYSTEM :DETERMINATION OF THE FREQUENCY F OF THE MACHINERESONANT FREQUENCY OF THE SPRING FO = F/5STIFFNESS K OF THE SPRING : FO =M = mass of the machine