| 摘要 |
<p>This see-saw, especially as a plaything (for a toy), comprises two arched parallel longitudinal members (1) which are secured to each other. Each of the longitudinal members includes, in the vicinity of its two ends, a cam (4) which is articulated (5), capable of extending in an adjustable and progressive manner in the vertical plane perpendicular to the said longitudinal member. <IMAGE></p> |
