Vibration-preventing rubber device

Claim 1

A vibration-preventing device comprising: an inner cylinder; an upper plate; a partition wall having a hub portion extending substantially parallel to said inner cylinder; a lower plate, said partition wall being positioned outside of said inner cylinder and being interposed between said upper plate and said lower plate, said upper plate and said lower plate being connected to the inner cylinder; an upper vibration-preventing rubber member interposed between the partition wall and the upper plate; an upper elastic film interposed between the partition wall and the upper plate, said upper vibration-preventing rubber member and said upper elastic film cooperating to define an upper damper liquid chamber; a lower vibration-preventing rubber member interposed between the partition wall and the lower plate; a lower elastic film interposed between the partition wall and the lower plate, said lower vibration-preventing rubber member and said lower elastic film cooperating to define a lower damper liquid chamber; an orifice which fluidly communicates said upper damper liquid chamber with said lower damper liquid chamber; and an elastic element outside of said damper liquid chambers and independent of said upper and lower elastic film, interposed between said inner cylinder and said hub of said partition wall, said elastic element being substantially axially coextensive with said hub, being in direct contact with one of said inner cylinder and said hub of said partition wall and, in the unloaded condition, being spaced from and out of direct contact with the other of said inner cylinder and said hub of said partition wall and cooperating to dampen low frequency vibrations, intermediate frequency vibrations and upper frequency vibrations with said vibration-preventing members.