Patent ID: 7806420

Claim:
A damping system for use with a mechanism having a first element which moves toward and away from a second element, the damping system being tuned to at least partially damp a chosen frequency, the system comprising: a variable volume chamber in mechanical communication with the mechanism such that movement of the first element in a first direction with respect to the second element reduces the volume of the chamber and movement of the first element in an opposite second direction with respect to the second element increases the volume of the chamber; a collection chamber; an inertia track having a first end in fluid communication with the variable volume chamber and an opposed second end in fluid communication with the collection chamber, the inertia track having a cross sectional area and a length; a fluid disposed in the variable volume chamber, the inertia track and at least a portion of the collection chamber, the fluid having a fluid density; a gas disposed in at least a portion of the collection chamber; a volume of fluid being displaced into or from the variable volume chamber by movement of the first element relative to the second element whereby the gas disposed in the collection chamber is compressed and expanded, the volume of fluid displaced per unit of movement being defined as dV/dx; an actual fluid mass for the inertia track being given by the formula; actual fluid mass=(cross sectional area)×(length)×fluid density; the system having a system effective mass given by the formula; system effective mass=(( dV/dx )/(cross sectional area)) 2 ×actual fluid mass; a compliant tuning member in fluid communication with the chamber, the compliant tuning member having a deflection stiffness and an area; the system having a system effective stiffness given by the formula; system effective stiffness=(( dV/dx )/(Area of compliant member)) 2 ×deflection stiffness; the system having a resonant frequency given by the formula; system resonant frequency=(system effective stiffness/system effective mass) 1/2 ; the cross sectional area and length of the inertia track and the deflection stiffness of the compliant tuning member being chosen such that the system resonant frequency is generally at the chosen frequency.