Patent ID: 7516947

Claim:
A hydraulic antivibration device comprising: a first attachment fitting, a cylindrical second attachment fitting, a vibration-isolating base connecting the second attachment fitting and the first attachment fitting to each other and composed of an elastomer, a diaphragm attached to the second attachment fitting to form a liquid-filled chamber between the diaphragm and the vibration-isolating base, a partition comparting the liquid-filled chamber into a first liquid chamber on the vibration-isolating base side and a second liquid chamber on the diaphragm side, and an orifice putting the first liquid chamber and the second liquid chamber into communication with each other, the partition including an elastic partition membrane and a pair of lattice members regulating the displacement amount of the elastic partition membrane from both sides thereof, wherein rib groups are provided projectingly on both faces of the elastic partition membrane, and include a plurality of first ribs and a plurality of second ribs, said first ribs intersecting with said second ribs, wherein the first ribs are set in height dimension so that tops thereof may be situated to be spaced apart from the lattice members; and wherein the second ribs are set in height dimension so that tops thereof may abut on the lattice members and in a rib width smaller than the first ribs.