| 摘要 |
A protected insertion letterbox comprises an air- and water- tight mail collection container 1 with an insertion slot 2 in the vicinity of the lower edge of its front wall 3, with an air - and water - tight gasket 4 which is fixed round the perimeter of the insertion slot, with a perforated access flap 5 which is movable so that the insertion slot can be closed or open, with the lower edge of the rear wall 8 joined to the lower edge of the front wall so that the lower part of the rear wall has the shape of a rising slope, with an internal access slot 12 with an internal access flap 14 movable so that slot 12 can be closed or open, and with a perforated support flap 9 fixed inside the container and movable so that it is either pressed against the rear wall or at a distance therefrom. Flaps 5,9,14 are all spring biassed to the closed position by respective springs 6,11, 16 acting on axles 7,10,15, and gasket 13 is air and water- tight. The arrangement is designed so that miscreants cannot introduce noxious gas or flammable liquid into premises via the letter box. |
