摘要 |
<p>The connection box is a cylindrical cup set into a hole in the wall. The side wall (12) has a lip (17) round the periphery, which fits outside the hole in the wall. To clamp the box in place, internal blocks (20) are drawn tight inside the wall panel. These internal blocks are on the end of a plastics strip (21). The strip is detached by folding it into the box, which allows the locking blocks to pass through a hole (48) in the side wall. Grips (24) on the inner end of the strip allow it to be pulled outward, pulling the locking blocks against the inside of the wall. Serrated tracks (41,42) on the outside of the box hold the locking blocks.</p> |