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Patent Searching and Data

Document Type and Number:
Japanese Patent JPH0414576
Kind Code:

PURPOSE: To prevent burglar by providing a pulse generation circuit connected to a switching means, a specific waveform pulse generation circuit to generate an output having waveform different from the output waveform of the pulse generation circuit and a waveform detection circuit.

CONSTITUTION: A waveform detection circuit 153 discriminates the output of a pulse generation circuit 139 from the output of a specific waveform pulse generation circuit 144 based on the pulse number and pulse width. When output signals of the generation circuit 139 and generation circuit 144 are received to generate an output only from the generation circuit 139, alarm signals from an alarm controlling circuit 2 are generated. After that, when the detection circuit 153 detects both outputs of the generation circuit 139 and generation circuit 144, the output is not provided to the controlling circuit 2. At that time, the controlling circuit 2 is held in an armed state, and the alarm signals are not generated. After that, when an open section is unjustly opened, a burglar alarm circuit is automatically switched in a state of alarm.

Application Number:
Publication Date:
January 20, 1992
Filing Date:
May 02, 1990
Export Citation:
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International Classes:
E05B45/06; B60R25/01; B60R25/10; B60R25/20; B60R25/24; B60R25/34; E05B49/00; E05B83/36; G08B13/00; (IPC1-7): E05B45/06