| 摘要 |
<p>A seat board is tilted in a forward or backward direction as a method in order for a user to have comfort in using a chair. A flexible elastic member is used so that the seat board can be smoothly tilted, and also returned to an original position. A tension spring and a pressure spring are presented as an example of the flexible elastic member, and a constitution is improved so that the same can be stably operated.</p> |
