摘要 |
An illuminating device comprises a housing having a light compartment and an off push-button located on the front wall thereof. The housing encloses a battery powered electrical circuit including a normally-open motion detection switch, a light bulb, a latching circuit, a control gate, and a normally open, momentary-closing reset switch. The housing is adapted to be removably fastened at a convenient location on an internal wall of a home. When the wall is shaken by a major earthquake that is likely to knock out the electric service in the area involved, the initial closing of the motion detection switch latches the latching circuit to provide a high level signal that opens the control gate and completes the electrical circuit to ground, thereby turning on the light bulb. When the earthquake occurs during the night time, the housing can be removed from the wall and used as a portable flashlight. Once turned on, the light bulb can be turned off by manually depressing the off push-button which momentarily closes the reset switch and thereby unlatches the latching circuit.
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