| 摘要 |
Lowering the bridge (4) causes a slide (28) mounted on a second fixed support (3) for the bridge to move into a lower position and raising the bridge moves the slide into an upper position. A magnetic fastener (38) on the slide is designed to be positioned directly opposite a magnetic fastener (33) on the second support when the slide is in the upper position, so that the slide is held in this position. When the bridge is lowered, couplings (40, 41) on the slide and bridge are designed to secure the slide to the bridge by magnetism, so that raising the bridge will move the slide into its upper position. |
