Leaf spring rotational vibration absorber

A vibration damping device for use with a downhole tool, the downhole tool having a tool axis and including a drill string component, the vibration damping device comprising:

• an inertia ring rotatably mounted on the drill string component and defining a radial interface therewith, the inertia ring including at least one cutout defining at least two chambers therein, wherein the drill string component forms an end wall and an inner wall of each chamber,
• a fluid disposed in the chamber;
• a leaf spring disposed in the chamber, wherein the leaf spring has a first spring end and a second spring end, wherein the first spring end is fixedly attached to one of the inertia ring or the drill string component, wherein the second spring end engages the other of the inertia ring or the drill string component, and wherein the leaf spring divides the chamber into first and second chamber portions each having a volume, and wherein relative rotation between the inertia ring and the drill string component distorts the leaf spring so as to vary the volumes of the first and second chamber portions;
• and
• a stop mechanism that mechanically limits the degree of relative rotation between the inertia ring and the drill string component.