| 摘要 |
A motion and orientation responsive device having a pendulum pivotally mounted between its ends, and means for detecting relative displacement of the upper pendulum end and a zero position reference on the pendulum support from certain normal relative positions thereof in response to either or both translational and rotational displacements of the device. Presently preferred embodiments of the invention are a seismic or earthquake alarm, an intrusion alarm, and a tilt alarm. In these preferred embodiments, the pendulum shaft is a slender resilient wire, and its pivot is situated close to its lower center of mass in order to amplify the lateral motion of the upper pendulum end for a given angle of pendulum rotation and thereby enhance the sensitivity of the device to low magnitude displacements. The pendulum and zero position reference in one preferred embodiment are uniquely constructed and arranged to automatically align themselves in a zero position when the device is stationary in its normal orientation without the necessity of precisely positioning or adjusting the alarm device to compensate for manufacturing tolerances or improper orientation of the object which supports the device. A vibratory or acoustically actuated electrical control circuit for the device and other uses.
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