| 摘要 |
<p>The see-saw clamp is a plate or similar body which is attached to a see-saw body and moves in a groove so that when the see-saw body tips up it becomes wedged and pressed against one or both side walls of the groove, where the see-saw body is then held firm by the pressure. The cross-section of the clamp is such that when the index card or other article which slides between two parallel walls is at a certain incline the clamp can be immediately clamped between the walls although it can be released equally rapidly when the pressure on the see-saw body is released.</p> |
