Communications: electrical – Condition responsive indicating system – Specific condition
Patent
1989-05-15
1990-12-11
Swann, III, Glen R.
Communications: electrical
Condition responsive indicating system
Specific condition
200 6141, 200 6193, 340516, 340545, 340546, G08B 1308, G08B 1314
Patent
active
049773925
ABSTRACT:
Generally there is provided a cabinet alarm device having a protruding switch lever arm arranged such that it is held open during closure of a cabinet door, but is allowed to close when the cabinet door is opened. The switch is pivotally mounted and urged toward its closed positionby a spring under tension, such as a rubber strip or O-ring fixed to the switch arm and alarm case. This switch controls power to the electronic circuit which includes two oscillator and two controlling comparators. A first oscillator drives an annunciator at a preset high resonant frequency, while a second oscillator operating at a low frequency pulsates the tone. A first controlling comparator circuit operates to disable the tone circuit after a fixed time delay to allow an audible battery check during that delay but preventing further tone unless the circuit is energized for a longer period. A second controlling comparator disables the first comparator and thereby enables the alarm circuit after a preset longer delay or upon detection of sufficient multiple operations.
REFERENCES:
patent: 3797006 (1974-03-01), Reininger
patent: 3995268 (1976-11-01), Ferrari
patent: 4030087 (1977-06-01), Ritchie et al.
patent: 4212300 (1980-07-01), Meals
patent: 4641054 (1987-02-01), Takahata et al.
patent: 4688023 (1987-08-01), McGill et al.
patent: 4701702 (1987-10-01), Kruger
Swann III Glen R.
White Douglas B.
LandOfFree
Security alarm system and switch does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Security alarm system and switch, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Security alarm system and switch will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-392083