Patent ID: 8424854

Claim:
A fluid-filled vibration damping device comprising: a first mounting member and a second mounting member connected by a main rubber elastic body; a pressure-receiving chamber whose wall is partially constituted by the main rubber elastic body; an equilibrium chamber whose wall is partially constituted by a flexible film, the pressure-receiving chamber and the equilibrium chamber being filled with a noncompressible fluid; a partition member partitioning the pressure-receiving chamber and the equilibrium chamber while being supported by the second mounting member; a low-frequency orifice passage and at least one high-frequency orifice passage tuned to higher frequency than the low-frequency orifice passage, being formed in the partition member for communicating the pressure-receiving chamber and the equilibrium chamber with one another; at least one valve body disposed at least at one opening of the high-frequency orifice passage, the valve body being provided with a spring member that in a nonloaded state positions the valve body away from the opening of the high-frequency orifice passage to hold the high-frequency orifice passage in an open state, and on a basis of relative pressure fluctuations arising between the pressure-receiving chamber and the equilibrium chamber the valve body being adapted to be urged closer to the opening of the high-frequency orifice passage in opposition to a holding force of the spring member so as to block the high-frequency orifice passage, wherein the valve body and the spring member are integrally composed by a valve rubber projection that is formed projecting towards at least one of a press-receiving chamber end and an equilibrium chamber end in the opening of the high-frequency orifice passage; and the partition member includes a passage hole connecting the pressure-receiving chamber and the equilibrium chamber, while supporting a passage-defining rubber part adapted to block the passage hole; the passage-defining rubber part has a communication hole connecting the pressure-receiving chamber with the equilibrium chamber through the passage hole so that the high-frequency orifice passage is constituted by the communication hole; and the valve rubber projection is integrally formed with the passage-defining rubber part at a rim of opening of the communication hole.