Fluid filled vibration damping device and method of producing the same

A method of manufacturing a fluid filled vibration damping device including:

• a first mounting member;
• a second mounting member of tubular shape, disposed such that the first mounting member is located on a side of a first open end portion of the second mounting member;
• a main rubber elastic body elastically connecting the first mounting member and the second mounting member, and fluid-tightly sealing off the first open end portion of the second mounting member;
• a flexible rubber film fluid-tightly sealing off a second open end portion of the second mounting member;
• a partition member disposed between opposing faces of the main rubber elastic body and the flexible rubber film, and supported by the second mounting member;
• a pressure-receiving chamber formed on one side of the partition member with a non-compressible fluid sealed therein, the pressure-receiving chamber being partially defined by the main rubber elastic body and subjected to an input of vibration;
• an equilibrium chamber formed on an other side of the partition member with the non-compressible fluid sealed therein, the equilibrium chamber being partially defined by the flexible rubber film and allowed to have a variable volume;
• an orifice passage connecting the pressure-receiving chamber and the equilibrium chamber;
• and being formed by utilizing the partition member;
• a holder member of tubular shape into which the second mounting member is press fitted so that the second mounting member adapted to be mounted via the holder member on a target member whose vibration is requested to be damped, the holder member including an annular holding portion integrally formed at one open end thereof so as to project radially inwardly;
• a cover plate member having an outside diameter smaller than an inside diameter of the holder member, and disposed within the holder member with an outer peripheral portion thereof supported by the annular holding portion of the holder member, and fixedly clamped by and between the second open end portion of the second mounting member and the annular holding portion, wherein the second open end portion of the second mounting member has a tapered outer circumferential surface with a diameter gradually decreasing toward a tip end, and wherein a sealing rubber is disposed for fluid-tightly closing a gap formed between the second open end portion of the second mounting member, and the cover plate member as well as the holder member so that an tightly closed air chamber partially defined by the cover plate member is formed on a side opposite from the equilibrium chamber with the flexible rubber film interposed therebetween, the method comprising the steps of:
• preparing a fluid filled vibration damping device body in which the first and second mounting members are connected by the main rubber elastic body with the pressure-receiving chamber and the equilibrium chamber formed therein, separately from the holder member and the cover plate member;
• setting the cover plate member with respect to the holder member with the outer peripheral portion of the cover plate member superposed on and supported by the annular holding portion of the holder member in position;
• press-fitting the second mounting member of the fluid filled vibration damping device body into the holder member so that the outer peripheral portion of the cover plate member is fixedly clamped by and between the second mounting member and the annular holding portion of the holder member, while the gap formed between the second mounting member and the holder member as well as the cover plate member is fluid tightly closed by the sealing rubber.