| 摘要 |
PURPOSE:To improve the riding comfort and driving stability of vehicle by changing the spring constant by switching on and off a sub-spring disposed at the top end of the piston rod. CONSTITUTION:The piston rod 3 has on its top end a fixedly attached cylinder unit 10, in whose cylinder 11 a piston 12 is inserted slidably in the vertical direction. The piston 12 has on its top and bottom oil chambers S1, S2, and a sub- spring 4 is disposed between the piston 12 and cylinder 11. In a hollow space at the top end of the piston rod 3, a tubed and bottomed adjusting rod 13 is inserted to open or close liquid passages 3a, 3b, 13a, 13b which communicate between the oil chambers S1, S2. When said liquid passages are open, the spring constant will be the combination of that of the main spring 14 and sub-spring 4, and by closing the liquid passages, the spring constant will be solely that of the main spring 14. |
