| 摘要 |
<p>The alarm device is activated in response to unauthorized movement of the article. The device has a motion detection mechanism, a signalling mechanism and a logic and timing device responsive to the motion detection device, for causing the alarm device to produce an alarm. The alarm is only activated if the motion detection mechanism detects an initial motion and a predefined pattern of continual motion following this initial motion. A device reduces the electrical current demand of the logic and timing device if no motion is detected by the detection device within a predetermined interval following detection of the initial motion.</p> |
