Question

plz explain untuned dry friction damper..????

Answer 1

The dry-friction damper consists of a shock-absorbing mass with a flexible link with the frame, dry friction shoes coupled to the mass, and an expansion spring to provide the necessary amount of dry friction. The damper is designed to reduce normal pressure on the contact surfaces when there is a change in direction of the absorbing mass by incorporating an inertia mass which has a flexible link with the shoes. During oscillation in a system inertia mass undergoes various accelerations, and the greater the acceleration on the inertia mass the smaller is the effort with which shoes are pressed against the friction surfaces. With a sufficiently rigid link the aacceleration of the inertia mass is virtually equal to the acceleration of the absorbing mass which means that with maximum acceleration of the absorbing mass the dry friction force will be the least.