Fluid-filled resilient support structure

Claim 1

A fluid-filled resilient support structure connected between two members of a vibration system, comprising: an inner sleeve fixed to one member of said two members of the vibration system; a first resilient member having an annular shape, disposed radially outwardly of said inner sleeve in coaxial relation with each other, with a predetermined radial distance therebetween; a pair of generally annular closure members disposed at opposite axial ends of said inner sleeve and said first resilient member, said closure members fluid-tightly closing opposite ends of an annular space formed between said inner sleeve and said first resilient member; a cylindrical member fitted on an outer surface of an axially intermediate portion of said inner sleeve; a generally annular thick-walled orifice member disposed radially outwardly of said cylindrical member in coaxial relation with each other, with a predetermined radial distance therebetween, said orifice member including a radially outer portion sandwiched between upper and lower portions of said first resilient member in an axial direction thereof, said orifice member having a circumferential groove formed continuously in an outer circumferential surface thereof, said circumferential groove having a length not less than one full outer circumference of said orifice member, said orifice member further having communication holes which communicate at their one end with corresponding ends of said circumferential orifice, and at their other end with said annular space inside said first resilient member; a second resilient member having an annular shape, disposed between said orifice member and said cylindrical member and secured thereto, said second resilient member, said orifice member and said cylindrical member cooperating with each other to axially divide said annular space, and further cooperating with said inner sleeve, said first resilient member and said pair of closure members, to define a pair of annular fluid chambers filled with an incompressible fluid; and an outer sleeve fixed to the other one of said two members of the vibration system and fitted on the outer surface of said orifice member, said outer sleeve fluid tightly closing said circumferential groove, so as to define a continuous circumferential orifice having a length corresponding to that of said circumferential groove, said pair of fluid chambers communicating with each other through said circumferential orifice and said communication holes.