| 摘要 |
PURPOSE:To prevent an encapsulated gas from leakage and a film from breakage and enhance the durability by using a multi-layer film consisting of highpolymer film having a low permeability for the encapsulated gas in a gas chamber and rubber-based elastic highpolymer body provided with oil resistance and flexibility, which are piled one over another. CONSTITUTION:A gas chamber 18, which is provided in a pressure vessel 12 of a gas spring 10 and in which inert gas such as nitrogen gas is encapsulated, is separated from an oil-encapsulated liquid chamber 19 by a partition film 25. The gas chamber 18 side of this partition film 25 consists of a highpolymer film 27 having a lower permeability for the encapsulated gas, while the oil chamber 19 side shall be in elastomer such as polyurethane elastomer which is oil resistant and flexible, and they are piled one over another to constitute a multi-layer structure. This prevents the encapsulated gas from leaking to the liquid chamber 19 side, eliminates risk of film breakage, and enhances the durability. |
