Abstract: A hydraulic antivibration device capable of sufficiently reducing strange sounds is provided. The one in a first embodiment includes first ribs whose tops are spaced apart from lattice members and second ribs having tops abutting on the lattice members and a smaller rib width than the first ribs. When an elastic partition membrane impinges on the lattice members with vibration, the second ribs resist and the elastic partition membrane impinges moderately on the lattice members, so that strange sounds can be reduced. In a second embodiment, such first and second displacement-regulating protrusions are provided that are disposed asymmetrically relative to a phantom plane passing through a center of the elastic partition membrane in its thickness direction.

Abstract: A hydraulic antivibration device capable of sufficiently reducing strange sounds is provided. The one in a first embodiment includes first ribs whose tops are spaced apart from lattice members and second ribs having tops abutting on the lattice members and a smaller rib width than the first ribs. When an elastic partition membrane impinges on the lattice members with vibration, the second ribs resist and the elastic partition membrane impinges moderately on the lattice members, so that strange sounds can be reduced. In a second embodiment, such first and second displacement-regulating protrusions are provided that are disposed asymmetrically relative to a phantom plane passing through a center of the elastic partition membrane in its thickness direction.

Abstract: A hydraulic antivibration device is provided that is capable of reducing greatly strange sound upon inputting of high amplitude while meeting both a low dynamic spring characteristic upon inputting of low amplitude and a high damping characteristic upon inputting of high amplitude. According to the device 100 of the invention, because an elastic partition membrane 15 is arrested by displacement-regulating ribs 17, 19 to regulate its displacement, and openings 54, 56 are pierced to provide an escape for the elastic partition membrane 15, it is possible to reduce greatly strange sounds upon inputting of large amplitude while meeting both a low dynamic spring characteristic upon inputting of low amplitude and a high damping characteristic upon inputting of large amplitude (intermediate amplitude) vibration.