Patent ID: 9506522
Filing Date: 2016-11-29
CPC Classification: B60K,F16F

Claim Text:
1. A fluid-filled vibration damping device comprising: a first mounting member; a second mounting member; a main rubber elastic body elastically connecting the first mounting member and the second mounting member; a pressure receiving chamber whose wall is partially defined by the main rubber elastic body; an equilibrium chamber whose wall is partially defined by a flexible film; a partition member partitioning the pressure receiving chamber and the equilibrium chamber from each other; a non-compressible fluid sealed in the pressure receiving chamber and the equilibrium chamber; an orifice passage mutually connecting the pressure receiving chamber and the equilibrium chamber; at least one connecting hole provided through the partition member to communicate the pressure receiving chamber and the equilibrium chamber; and a closing rubber elastic plate provided such that the closing rubber elastic plate is overlapped from a pressure receiving chamber side on the connecting hole to close the connecting hole, the closing rubber elastic plate is opened based on elastic deformation, and a pressure of the pressure receiving chamber is applied to a first surface of the closing rubber elastic plate, while a pressure of the equilibrium chamber is applied through the connecting hole to a second surface of the closing rubber elastic plate, wherein the closing rubber elastic plate includes a plurality of abutting retaining parts at its outer circumference edge part, the abutting retaining parts are held in an overlapping state to the partition member, and are spaced away from one another in a circumference direction, wherein between adjacent abutting retaining parts in the circumference direction, the closing rubber elastic plate includes at least one elastic deformation area configured to be elastically deformed based on a pressure difference between the pressure receiving chamber and the equilibrium chamber to be separated from the partition member and to open the connecting hole, allowing fluid flow action between the pressure receiving chamber and the equilibrium chamber through the connecting hole, and wherein at least one mass part is provided at an intermediate part of the elastic deformation area in the circumference direction, the at least one mass part and the elastic deformation area constitute at least one mass-spring system, a resonance frequency of the mass-spring system is tuned to 50 Hz or greater, and a tuning frequency of the orifice passage is set to a lower frequency than the resonance frequency of the mass-spring system.