| 摘要 |
PURPOSE:To enable switching spring rigidity as a vibro-isolating support device between two stages of 'hard' and 'soft' by providing a pushing means within a control hole for pressing a valve member for shutting off the continuity of fluid chambers via an orifice toward the dead end edge of the control hole. CONSTITUTION:When a push rod 54 has been retreated with a drive device 56, communication passages 36 and 36 become continuous to each other via a space formed between the dead end edge 34 of a mounting hole 32 and a valve body, and two fluid chambers 30 and 30 fall in a condition continuous to each other, thereby reducing the spring rigidity of a bush 2. On the other hand, when the push rod 54 has been made to advance, the valve body is elastically deformed, the opening of the communication passages 36 for the dead end edge 34 of the mounting hole 32 is closed due to the pressing and contact of the valve proper with said edge 34, and the continuity of the two fluid chambers 30 is broken. In this condition, even when a load is applied to the bush 2 in a direction orthogonal with an axial line, a fluid in the chambers 30 does not move and the bush 2 comes to show hard spring rigidity as a whole. |
