| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a derricking device in which a user is capable of naturally and smoothly rising without requiring his own force, and capable of lightly falling by only putting his weight on it by changing spring force corresponding to load changing in accordance with a body inclination angle. SOLUTION: Sliders 21, 22, 23 to be pressed by compression coil springs 31, 32, 33 of different spring forces are provided, movable cams 51, 52, 53 which are vertically movable are dispsoedon tips of the respective sliders, so as the sliders 21, 22, 23 are moved forward by the springs 31, 32, 33, the movable cams 51, 52, 53 move up in order for pushing up balls 14d, 14e, 14f provided on a front edge of the movable frame 11 in order to let the movable frame 11 rise.</p> |
