JPH0512865Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a crime prevention alarm system using crime prevention sensors such as a window opening/closing detector, a human body intrusion detector, and a window glass breakage detector, and particularly relates to an operation indicator light.

[Prior art] A security system has come into use that uses a pair of digital transmission lines to sequentially and cyclically call up crime prevention detectors, etc. by address polling, etc., and collects information from each detector. In such a system, a digital signal is superimposed on the power supply line to each detector, and therefore the current consumption in each detector is naturally limited.

[Problems to be solved by the invention] Each security detector of the security system described above can be provided with an operation indicator light that can be used to confirm the operation of the detector during an operation test. As the number of lines increased, problems arose, such as the inability to maintain a predetermined line-to-line voltage.

[Means for solving the problem] This idea connects a central monitoring panel and multiple security detectors via a pair of power supply/transmission lines, and uses digital transmission to exchange information with each other. In the security device used, each of the security detectors is provided with an operation indicator light and a pulse generator with a large duty ratio, and when the security detector is activated, the indicator lights are lit in pulses by the output of the pulse generator. This solves the above problems.

[Embodiment] Fig. 1 shows the overall configuration of a crime prevention alarm device using the circuit of this invention, and Fig. 2 shows a schematic block diagram of the main parts.

In FIG. 1, 1 is a central monitoring board, l is a transmission line, which extends from the central monitoring board 1, and is connected to a plurality of window opening/closing detectors 2, human body detectors 3, window glass breakage detectors 4, etc. Each detector 2, 3, 4 is provided with an operation indicator light 5. Furthermore, the operating status is sent from the central monitoring panel 1 to the security company's disaster prevention center via telephone lines, etc., and if it is installed in a building, a signal from a remote switch for the last person to leave is input. It is configured.

FIG. 2 shows an example of a circuit for an operation display 5 provided in the various detectors 2, 3, 4 of such a security alarm system. In the figure, a pair of power supply/transmission lines l ₁ and l ₂ extend from the central monitoring panel 1 to various security detectors 2,
Connected to 3 and 4.

Detectors 2, 3, and 4 are interference prevention diodes 2
1. A constant voltage circuit 22, a transmission control circuit 23, a pulse generator circuit 24, a sensor 25, and an operation indicator light 5 are provided, and when the sensor 25 generates a signal such as a window opening/closing signal or a signal indicating an intrusion of a human body, A digital signal coded to that effect is sent from the transmission control circuit 23 to the central monitoring board 1 via the transmission lines l ₁ and l ₂ . The signal from the sensor 25 is also input as a drive signal to the pulse generator 24, and a pulse output with a large duty ratio as shown in FIG. 3 is applied to the operation indicator lamp 5 to turn it on. The average value of such pulsed current is extremely low,
Even when a plurality of detectors 2, 3, and 4 operate, the drop in line voltage is negligible and is extremely small.

In this embodiment, the sensor 25 is shown as being integrated with the detector, but they may be separate from each other. In addition, the operation indicator light 5 is controlled by the central processing unit of the central monitoring board 1 so that it is turned on only during the operation test of the sensor by the operation of the central monitoring board 1.
If the settings can be made using the CPU, the location of the detectors 2, 3, and 4 will not be needlessly known to an intruder or the like.

[Effects of the invention] As mentioned above, when this invention is used in a lighting circuit for the operation indicator light of a security detector connected to a crime prevention device that shares power supply and digital signals through a pair of lines, The influence on the voltage is extremely small, and it is effective when used for checking the operation of a crime prevention device that connects a large number of crime prevention detectors.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the overall configuration of the device of this invention.
FIG. 2 is a schematic block diagram of the main part of FIG. 1, and FIG. 3 shows pulse waveforms showing the operation of FIG. 2. 1... Central monitoring board, 2, 3, 4... Security detector, 5... Operation indicator light, l... Transmission line, 24...
...Pulse generator.

Claims (1)

[Scope of utility model registration request] In a crime prevention device using digital transmission in which a central monitoring panel and multiple crime prevention detectors are connected via a pair of power supply and transmission lines and mutually exchange information, an operation indication is displayed on each of the crime prevention detectors. 1. A crime prevention alarm device comprising: a light and a pulse generator having a large duty ratio; and when a crime prevention detector is activated, the indicator light is lit in pulses by the output of the pulse generator.