| 摘要 |
<p>A letter-plate 1 comprises a pair of frames 2, 3 adapted to be 5 fitted on opposing sides of a door and to inter-engage through a slot cut into the door. One or both frames is provided with a flap 9 that covers an aperture defined by the frame. The flap is pivotally mounted along one side of the frame via at least one peg 13 that is located in a channel 11 containing a damping 10 device. A magnetic arrangement 16, 18 is provided whereby in use the flap hangs downward and is retained in a closed position covering the aperture until manually raised. The flap 9 is then capable of returning to its closed position under gravity against the force of the damping means. Preferably, one of the frames is provided with a pair of parallel, flexible elastomeric strips 19 (figure 4, not shown) that cover the aperture defined by the frame whereby items pushed through the frame deform and pass between adjacent edges of the strips.</p> |
