| 摘要 |
PROBLEM TO BE SOLVED: To block an introduction duct powerlessly and without an artificial operation at the invasion of Tsunami.SOLUTION: A pipe conduit cutoff device 1 is arranged at a vertical part of an introduction duct 2 arranged in a building, and blocks the introduction duct 2 at the invasion of Tsunami. In a normal time, a ventilation plate 8 which is positioned so as to block the inside of the introduction duct 2 but makes air flow therethrough, and a water block plate 6 integrally arranged at the ventilation plate 8, and located in a position which does not block a flow of air passing through the ventilation plate 8 as much as possible are integrally arranged in the introduction duct 2 so as to be turnable at a required angle. A counter weight 9 which acts so that the ventilation plate 8 is not rotated by ventilation is arranged. At emergency, the ventilation plate 8 and the water block plate 6 are integrally rotated while withstanding an operation force of the counter weight 9 generated by a collision of sea water to the ventilation plate 8 at the invasion of the sea water into the introduction duct 2, and the inside of the introduction duct 2 is blocked. By this constitution, at the invasion of Tsunami, an air conditioning duct can be surely blocked powerlessly and without an artificial operation by utilizing that a water flow acts on the ventilation plate. |
