| 摘要 |
PURPOSE:To make it possible to optionally change the total spring constant of a plurality of springs, by providing a means for changing the initial displacement of at least one of springs. CONSTITUTION:A groove 21 is formed in the lower surface of a flange 20 formed in the lower end face of a hydraulic cylinder 18, and receives a first coil spring 22. Further, a piston 23 is held in the inside of the hydraulic cylinder 18, and the outer peripheral stepped part 25 of a projection formed on the lower surface of the piston 23 receives the upper end of a second coil spring 26. By adjusting the hydraulic pressure in the cylinder 18 and the external force F, the spring constant of a coil suspension unit 4 may be optionally changed. |
