| 摘要 |
This invention relates to a door or window alarm contact sensor of the type comprising a two part assembly including a permanent magnet 5 and a reed switch 63 responsive to the magnet. One of the magnet and the switch is suitable for mounting on a door or window frame 11 and the other of the magnet and the switch is suitable for mounting on a door or window handle 15. The magnet and the switch are arranged so that the state of the switch is dependent on whether the handle 15 and locking arm 17 is in a locked configuration (figure 7) or an unlocked configuration (figure 6). In this way, it is possible for the sensor to determine whether or not the door or window is locked or unlocked. The sensor may further comprise a wireless transmitter 67 and a battery 69 in the handle 15, allowing transmission of a switch status to a remote alarm assembly. The sensor may comprise a further two part assembly for detecting whether the door or window is in an open or closed configuration. |
