Patent ID: 6450486
Filing Date: 2002-09-17
Classification: F16F

Abstract:
A liquid sealed type cylindrical anti-vibration apparatus comprising:an outer cylinder and an inner cylinder arranged to be radially spaced apart from each other; an elastic member connecting the outer cylinder and the inner cylinder; wherein said elastic member is provided with a liquid chamber recess forming both a main liquid chamber and an auxiliary liquid chamber, both of which are interposed between the elastic member and the outer cylinder; said main liquid chamber and said auxiliary liquid chamber are filled with working liquid, and communicate with each other by an orifice passage, wherein the liquid chamber recess of the elastic member is covered by an auxiliary liquid chamber cover and a main liquid chamber cover, a stopper is provided to project into the main liquid chamber integrally with the main liquid chamber cover, a top portion of the stopper is arranged to be broad and a passage portion is formed around the stopper, whereby a liquid column resonance having a medium frequency range is generated by liquid flow accompanied with volume variation in the main liquid chamber, a partition wall, which divides said main liquid chamber and said auxiliary liquid chamber by extending radially from two opposing sides of the inner cylinder, is formed in a thin wall by means of a part of the elastic member and is set to resonate by membrane in a medium to high frequency range; and a pair of end walls formed in a thin wall on a part of the elastic member extending in a radial direction at axially both end regions of the inner cylinder as a part of the wall portion surrounding the liquid chamber recess, wherein said end walls are set to resonate by membrane in a medium to high frequency range, and the partition wall and the end walls are set to generate a cooperative resonance in a medium to high frequency range by arranging to synthesize the simultaneously generated membrane resonance on the partition wall and the end walls.