| 摘要 |
PROBLEM TO BE SOLVED: To provide a crime prevention sensor having high security, whereby even if an intruder tries to bring an external magnet close to a reed switch, the reed switch is reversely operated from ON to OFF, or from OFF to ON by detecting magnetic force of the external magnet. SOLUTION: This crime prevention sensor is equipped with two reed switches 37, 39 and one magnet 15. The reed switches 37, 39 are mounted on a printed circuit board 41, and is connected to a circuit (not shown in the figure) for detecting the open or closed state of a contact. In addition, this sensor is equipped with a case 43 mounted to a window frame 19 by a case mounting part 101 as a box to house the reed switches 37, 39, the magnet 15 is polarized in the longitudinal direction of the reed switches 37, 39, it is disposed on an opening and closing window 21 by a magnet mounting surface 102, and it is relatively moved parallel with the longitudinal direction of the reed switches and also parallel with the printed circuit board 41. COPYRIGHT: (C)2006,JPO&NCIPI
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