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A fluid-filled cylindrical elastic mount having an elastic body between an inner and an outer sleeve, a movable member movably disposed in a pressure-receiving chamber defined by the outer sleeve and the elastic body, a rigid member cooperating with the outer sleeve to define a space diametrically o

A fluid-filled cylindrical elastic mount having an elastic body between an inner and an outer sleeve, a movable member movably disposed in a pressure-receiving chamber defined by the outer sleeve and the elastic body, a rigid member cooperating with the outer sleeve to define a space diametrically opposite to the pressure-receiving chamber in a load-receiving direction of the mount, and a partition member having a flexible portion and dividing the space into two sections one of which serves as an equilibrium chamber disposed diametrically opposite to the pressure-receiving chamber. The movable member and the inner surface of the pressure-receiving portion define a fluid resonance portion for isolating high-frequency vibrations. An orifice passage is spirally formed for fluid communication between the pressure-receiving and equilibrium chambers, for damping low-frequency vibrations.

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1. A fluid-filled cylindrical elastic mount comprising: an inner and an outer sleeve which are disposed in spaced-apart relation with each other in a radial direction of the mount; an elastic body interposed between said inner and outer sleeves for flexible connection therebetween, and having a

1. A fluid-filled cylindrical elastic mount comprising: an inner and an outer sleeve which are disposed in spaced-apart relation with each other in a radial direction of the mount; an elastic body interposed between said inner and outer sleeves for flexible connection therebetween, and having a pocket open in an outer surface thereof and an axial void formed therethrough over an entire length thereof in an axial direction of the mount, said pocket and said axial void being formed in respective diametrically opposite portions of said elastic body which are opposite to each other in a load-receiving direction in which the mount primarily receives a vibrational load; said elastic body and said outer sleeve at least partially defining a pressure-receiving chamber such that said pocket is closed by said outer sleeve, said pressure-receiving chamber being filled with a non-compressible fluid, a pressure of said fluid in said chamber varying upon application of said vibrational load to the mount; a movable member accommodated in said pressure-receiving chamber freely movable over a predetermined distance in said load-receiving direction, said movable member defining a fluid resonance portion with respect to an inner surface of said pressure-receiving chamber; a rigid member disposed in said axial void, fixedly to said outer sleeve, and cooperating with said outer sleeve to define a space therebetween; a partition member disposed in said space so as to divide said space into two sections one of which acts as an equilibrium chamber filled with said non-compressible fluid, said partition member including a flexible film portion which is elastically deformable so as to change a volume of said equilibrium chamber for maintaining said fluid in said equilibrium chamber at a substantially constant pressure; an orifice-defining member disposed on the outer surface of said elastic body, and having an arcuate portion which covers at least an opening of said pocket, said arcuate portion having a spiral groove formed in an outer surface thereof, and a communication hole formed in communication with an inner end of said spiral groove and said pressure-receiving chamber; said outer sleeve closing said spiral groove, and thereby forming an orifice passage which communicates at one end thereof with said pressure-receiving chamber through said communication hole, and at the other end thereof corresponding to an outer end of said spiral groove with said equilibrium chamber. 2. A fluid-filled cylindrical elastic mount according to claim 1, further comprising an elastic stop secured to an inner surface of said rigid member such that said elastic stop protrudes in said axial void, in facing relation with said inner sleeve in said load-receiving direction. 3. A fluid-filled cylindrical elastic mount according to claim 2, wherein said rigid member includes a small-diameter portion which has a part-circumferential groove which is open in a radially outward direction of the mount, said elastic stop being formed on an inner surface of a bottom wall of said small-diameter portion which defines said part-circumferential groove. 4. A fluid-filled cylindrical elastic mount according to claim 1, further comprising another orifice-defining member which cooperates with said outer sleeve to define a connecting passage which communicates at one end thereof with said one end of said orifice passage and at the other end thereof with said equilibrium chamber. 5. A fluid-filled cylindrical elastic mount according to claim 4, wherein said another orifice-defining member has a cutout formed in a portion thereof which faces an outer surface of said rigid member, said flexible film portion of said partition member being secured to said portion of said another orifice-defining member so as to cover said cutout, said flexible film portion cooperating with said rigid member to define said equilibrium chamber. 6. A fluid-filled cylindrical elastic mount according to claim 5, wherein said outer sleeve and said flexible film portion of said partition member cooperate to define an air chamber as the other of said two sections of said space, said air chamber allowing said flexible film portion to expand so as to increase a volume of said equilibrium chamber. 7. A fluid-filled cylindrical elastic mount according to claim 1, wherein said movable member has an outer arcuate surface substantially following an arc of said outer sleeve, and an inner arcuate surface substantially following a radially inner surface of said pressure-receiving chamber near said inner sleeve. 8. A fluid-filled cylindrical elastic mount according to claim 7, wherein said predetermined distance of movement of said movable member is held within a range of 2-16 mm. 9. A fluid-filled cylindrical elastic mount according to claim 7, wherein a ratio of said predetermined distance to a radial dimension of said pressure-receiving chamber in said load-receiving direction is held within a range of 0.05-0.50. 10. A fluid-filled cylindrical elastic mount according to claim 7, wherein a sum of areas of said outer and inner arcuate surfaces of said movable member is not smaller than 1000 mm 2 . 11. A fluid-filled cylindrical elastic mount according to claim 1, wherein said non-compressible fluid has a kinematic viscosity of not higher than 500 centistokes. 12. A fluid-filled cylindrical elastic mount according to claim 1, wherein axes of said inner and outer sleeves are offset from each other so that said inner and outer sleeves are coaxial with each other when the mount is installed in position, with a static load acting on one of said inner and outer sleeves.