Patent ID: 8651467

Claim:
A fluid-filled type vibration damping device comprising: a first mounting member; a second mounting member; a main rubber elastic body connecting the first and second mounting members; a partition member supported by the second mounting member; a pressure receiving chamber whose wall portion is partially defined by the main rubber elastic body; an equilibrium chamber whose wall portion is partially defined by a flexible film, the pressure-receiving chamber and the equilibrium chamber being disposed on either side of the partition member and filled with a non-compressible fluid; an orifice passage permitting communication between the pressure receiving chamber and the equilibrium chamber; a moveable film disposed in the partition member, the moveable film having a film portion that receives on one side thereof a pressure of the pressure receiving chamber and on another side thereof a pressure of the equilibrium chamber, and an annular retaining portion integrally formed on a location of an outer peripheral side of the film portion while being supported by the partition member; a short passage formed in the partition member at a location of an outer peripheral side of a support portion that supports the annular retaining portion of the moveable film for permitting communication between the pressure receiving chamber and the equilibrium chamber; and a valve member that switches between a communicating state and a shut off state of the short passage being provided projecting to the outer peripheral side from the annular retaining portion, the valve member having a thick walled part projecting from the annular retaining portion to the outer peripheral side and a thin walled part which gradually becomes thinner toward a projection tip side projecting further to the outer peripheral side from the thick walled part, wherein the thin walled part rises toward a pressure receiving chamber side within the short passage and is elastically pressed on an inner wall surface of the short passage, wherein the pressure of the pressure receiving chamber is applied through the short passage to a pressure receiving chamber side surface of the thick walled part, while an equilibrium chamber side surface of the thick walled part is in contact with and supported by the partition member, wherein the pressure of the pressure receiving chamber is applied to one side of the thin walled part and the pressure of the equilibrium chamber is applied to another side of the thin walled part through the short passage, and wherein the thin walled part of the valve member projects facing further to the outer peripheral side from the thick walled part with a substantially triangular cross section and a base of the thin walled part is integrally bonded to the thick walled part of the valve member: and an angle formed by the base and a pressure receiving chamber side surface of the thin walled part is an obtuse angle while an angle formed by the base and an equilibrium chamber side surface of the thin walled part is an acute angle.