| 摘要 |
PURPOSE:To improve vibrationproof efficiency for low frequency vibration by forming a constriction giving continuity between fluid chambers into a spiral shape, and emphasizing only damping against the low frequency vibration with a resonance frequency kept at a prescribed value. CONSTITUTION:A valve means 10 has a constriction 11 and a pressure-sensitive movable valve 12 both provided on the central portion of a partition wall 4 for partitioning a fluid main chamber 5 from a fluid auxiliary chamber 7. The valve means 10 is formed by a top plate 13, a middle plate 14, a bottom plate 15, and rubber sheets 18, 19, 20. The upper and lower chambers 16, 17 provided in the valve means form fluid paths 23, 24 partitioned respectively into spiral shapes by constriction walls 21, 22 formed on a plane. The spiral shape can contribute to increase its overall length and the entire sectional area of the constriction 11 can be increased for the low frequency vibration without changing the resonance frequency, so as to exert large damping force. |
