Patent ID: 8857110

Claim:
A negative stiffness device for seismic protection of a structure, comprising: an anchor frame and a movement frame, the movement frame being laterally translatable relative to the anchor frame, the anchor frame having an extension portion extending toward the movement frame, the movement frame having an extension portion extending toward the anchor frame; a linkage pivotably connected to the extension portion of the anchor frame; a spring having a first end attached to the extension portion of the movement frame and a second end attached to the linkage, the spring having a spring force; wherein in a rest state, the spring is compressed to exert a preload force to the movement frame and does not displace the movement frame; wherein in an engaged state, the spring is configured to apply a lateral force to the movement frame such that the movement frame is displaced in a same lateral direction of a seismic load; and wherein the spring force is amplified by the linkage when the movement frame is laterally displaced to an amplification point.