Patent attributes
To provide a seismic isolation device, even if a relative height between friction plates, which are laminated in a hollow part of a laminated rubber body, and the laminated rubber body changes at a deformation of the laminated rubber body, which prevents allophone, vibration and shock from inside of the seismic isolation device (laminated rubber body), resulting superiority in durability, safety, and amenity. The seismic isolation device comprising: a laminated rubber body 2 in which elastic material layers 2b and rigid material layers 2c are vertically laminated one after the other; a plurality of friction plates 3 vertically laminated so as to be horizontally slidable and wholly enclosed in a hollow part 2a vertically penetrating the laminated rubber body; pressurizing means 4A, 4B arranged at a topmost portion and/or at a lowermost portion of the laminated friction plates and vertically adding pressure; and a friction reducing means 5 arranged between each outer peripheral portion of the plurality of the friction plates and an inner peripheral surface of the hollow part of the laminated rubber body. Even if a relative height of the friction plates and the inner peripheral surface of the hollow part of the laminated rubber changes, the friction reducing means smoothens the slide between them.