Magnetically destiffened viscous fluid damper

摘要

Disclosed is a vibration damping and isolation apparatus having a passive damping mechanism. The passive damping mechanism includes a piston and first and second elements of magnetic material with a shaft extending therebetween. The piston and shaft are linearly movable relative to one another upon application of forces to the damping apparatus. The shaft is spaced from an axial bore of the piston by a restrictive fluid flow annulus that is filled with a viscous fluid. A resilient seal mechanism, having a static stiffness, couples the first and second elements to the piston to define first and second viscous fluid filled chambers in fluid communication with the annulus. Shearing of the fluid as it is displaced through the annulus dissipates the forces. A magnetic mechanism generates magnetic forces that act on the first and second elements to destiffen the static stiffness of the resilient seal mechanism to improve vibration damping and isolation at low frequencies.