HYDRAULIC-PNEUMATIC DEVICE

A hydraulic-pneumatic device according to one embodiment of the present invention comprises: an outer cylinder; an inner cylinder; a piston which has a fixed mode and a motion mode and can thus reciprocate relative to the inner cylinder in the motion mode; and a free piston which divides a space between the outer cylinder and the inner cylinder into a first chamber and a second chamber and can reciprocate in the space between the outer cylinder and the inner cylinder, wherein a third chamber, namely an inner space of the inner cylinder, is filled with a liquid and when the piston moves towardone end of the inner cylinder in the motion mode, at least some of the liquid received in the third chamber moves to the first chamber or the second chamber. 根据本发明的一实施例的液压装置包括外缸；内缸；活塞，其具有固定模式和移动模式，并在所述移动模式中对于所述内缸相对地往复运动；以及自由活塞,其将所述外缸和所述内缸之间的空间分割为第一腔室和第二腔室，并能够在所述外缸和所述内缸之间的空间中往复运动，此时，液体填充在作为所述内缸的内部空间的第三腔室中，当所述活塞在所述移动模式中朝向所述内缸的所述一端移动时，填充在所述第三腔室中的所述液体的至少一部分移动到所述第一腔室或所述第二腔室中。