摘要 |
PROBLEM TO BE SOLVED: To provide a fire sensor whose responsiveness to heat is enhanced by increasing the coefficient of heat transfer to a heat-sensitive element. SOLUTION: A heat-sensing part of a thermistor 6 is positioned between the bottom plate 4a of an insect cover 4 and the bottom 5b of a shell cover 5, while protruding downward from a through hole provided in the bottom plate 4a of the insect cover 4. The thermistor 6 is disposed in a position that is on a straight line, connecting the center position of the shell cover 5 to muntins 5c and that deviates from the center position of the shell cover 5. The position of the thermistor 6 is set as a center and a plurality of flow-straightening fins 18, disposed radially in the direction of each end being positioned on a straight line passing through the center are provided within the shell cover 5. On a straight line, connecting the pair of muntins 5c facing across the center of the shell cover 5 to the position of the thermistor 6, a pair of flow-straightening fins 18 are provided on both sides across the thermistor 6. The one of the pair of flow-straightening fins 18 that is the closer to the muntins 5c is disposed at a position closest to the muntins 5c among the plurality of flow-straightening fins 18. COPYRIGHT: (C)2008,JPO&INPIT |