CN1119775C - Alarm reporting apparatus - Google Patents
Alarm reporting apparatus Download PDFInfo
- Publication number
- CN1119775C CN1119775C CN97104584A CN97104584A CN1119775C CN 1119775 C CN1119775 C CN 1119775C CN 97104584 A CN97104584 A CN 97104584A CN 97104584 A CN97104584 A CN 97104584A CN 1119775 C CN1119775 C CN 1119775C
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- CN
- China
- Prior art keywords
- circuit
- line
- current
- telephone line
- abnormality
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B25/00—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems
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- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Alarm Systems (AREA)
- Telephonic Communication Services (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
To detect the disconnection of the telephone line of an abnormality reporting device at a low cost without making any misjudgment. When telephone lines are opened, a line voltage monitoring circuit monitors the voltage across the telephone lines. Since the circuit monitors the voltage from a very small current, there is a possibility of making erroneous abnormality detection due to noise. Therefore, when the circuit detects abnormality, a line turn-on means turns on the lines and a line current monitoring circuit monitors the current flowing through the lines. Since the monitoring of the line current is performed by using a relatively large current, no misjudgment is caused by noise. When abnormality is detected while the line current is monitored, it is discriminated that one of the lines is disconnected and an informing means outputs a disconnection signal. It can restrict the increasing of system cost when the line turn-on times is little.
Description
The present invention relates to be used to utilize the panalarm of the warning system of telephone wire, relate in particular to the panalarm that can the monitoring phone line opens circuit.
Be used for the various warning systems in Centralized Monitoring buildings, apartment etc., by panalarm being installed and being made it connect Surveillance center at a distance, and monitor this class buildings in Surveillance center in each buildings, this class warning system is practicability already.Have that various sensors are for example antitheft, the sensor of taking precautions against natural calamities and so on links to each other with panalarm in this warning system, and when any such sensor detects abnormality, just sends alarm by circuit-line to Surveillance center.When this interrupted in this warning system because of such or such reason at telephone line, even when sensor detects abnormal phenomena, alarm can not arrive Surveillance center, makes warning system ineffective.
For this reason, for example be periodically to send signal to Surveillance center, and Surveillance center just monitor the cycle delivery status of sort signal from panalarm by time interval of one to two hour.If fail periodically to receive this signal, Surveillance center just can judge that telephone line interrupts, and sends the guard to investigate its security to corresponding buildings, and takes measures necessary as the case may be.
On the other hand, at this end of panalarm, in the transmission time of above-mentioned cyclical signal, then monitor electric current by telephone wire.If can not survey electric current at this moment, just can concluding in this telephone wire, panalarm has disruption, by making the hummer sounding, remind reliable personnel that this telephone line interrupts already.But between twice transmission period of periodic signal and telephone line when disconnecting can not be surveyed line interruption by line current, then when circuit disconnects the voltage between monitoring circuit, if just survey and assert that less than voltage telephone line interrupted already.
But, be to connect high resistance between the telephone line, very little electric current is being flow through survey this very little electric current when surveying line voltage distribution.In other words, owing to be to compare with the circuit electric current monitor to survey the interruption that less current is come the detecting telephone circuit with monitoring circuit voltage, just easily affected by noise and cause erroneous judgement probably.On the contrary, lessly because the watch-dog that utilizes line current to come monitoring circuit to interrupt has adopted bigger current value be subjected to noise effect, just can determine more reliably and open circuit.Thereby increased the number of times that utilizes line current to monitor so expected the transmission intercal that shortens periodic signal.But under such situation, owing to increased the number of transmissions, the other problem that systematic running cost increases can appear again.
By telephone line the abnormal phenomena that takes place is reported in the panalarm of destination being used for, the objective of the invention is to not to have the interruption that erroneous judgement ground comes the detecting telephone circuit with low expense.
In order to achieve the above object, finished the present invention.Existence detecting abnormal phenomena with this abnormal phenomena reports in the panalarm of the predetermined area, and this kind equipment is to monitor the voltage that is applied between this telephone wire when telephone line disconnects.When the watch-dog that utilizes line voltage distribution thus detects any abnormality, connect this telephone line and come the monitoring circuit electric current.When having detected any abnormality when this line current of monitoring, this equipment judges that promptly telephone line interrupts and the output look-at-me.
To achieve these goals, described panalarm comprises: the line voltage distribution supervising device is used for monitoring circuit voltage when telephone line disconnects, and surveys the abnormality of line voltage distribution; The line current supervising device is used for monitoring circuit electric current when telephone line is connected, and surveys the abnormality of line current; The circuit engaging means are used for carrying out the connection operation of the DC circuit of telephone line; And the decision maker that opens circuit, it is connecting line voltage distribution supervising device, line current supervising device and circuit engaging means.
When the line voltage distribution supervising device detects abnormality, the decision maker that opens circuit just impels the circuit engaging means to connect the DC circuit of telephone line, and when the line current supervising device detected abnormality subsequently when circuit is connected, this decision maker was to exist in the decidable telephone line to open circuit and export chopping signal.When line current supervising device equipment when circuit is connected provides unusual input, this decision maker is not have interruption in the decidable telephone line.
According to above structure, when disconnecting, telephone line interrupts, and line voltage distribution promptly descends, and the line voltage distribution supervising device just detects abnormality.Then, when not having the circuit electric current although telephone line is connected and flowing through, the line current supervising device just detects abnormality.As a result, the decision maker that opens circuit is just exported look-at-me.On the other hand, though when the line voltage distribution supervising device detects abnormal volotage owing to noise, then have line current to flow through when connecting telephone line subsequently not opening circuit, while circuit current monitoring device then detects this line current.When detecting this line current, the decision maker that opens circuit is promptly judged and is not had interruption.So do not export look-at-me, and can avoid the faulty operation that causes because of noise.
Monitoring by line current just judges have when interruption just to carry out at the circuit voltage monitoring equipment.Therefore the connection number of times of circuit can be reduced, thereby the operating cost of warning system can be prevented to increase.
In the present invention, can also in capacitor, accumulate minimum electric current, and can replace monitoring this minimum electric current that causes because of line voltage distribution by the discharge current of monitoring this capacitor, be able to monitoring circuit voltage thus.At this moment, noise becomes less to the influence of discharge current, thus can be under the little state of noise effect monitoring circuit voltage.So can reduce resulting from the faulty operation of noise, can further be reduced to the monitoring circuit electric current thus and connect the number of times of circuit.
Above-mentioned purpose of the present invention and characteristics can from below with reference to accompanying drawing to obtaining clearer understanding the explanation of most preferred embodiment, in the accompanying drawings:
Fig. 1 illustration used the structure of the warning system of panalarm of the present invention;
Fig. 2 is a circuit diagram, illustration panalarm of the present invention;
Fig. 3 is a circuit diagram, shows and understands the line voltage distribution supervisory circuit that is used for panalarm shown in Figure 2;
Fig. 4 is a circuit diagram, shows and understands the line current supervisory circuit that is used for panalarm shown in Figure 2;
Fig. 5 is a process flow diagram, shows the processing operation of understanding CPU shown in Figure 2 (CPU (central processing unit)); And
Fig. 6 is a circuit diagram, shows the improvement example of understanding line voltage distribution supervisory circuit shown in Figure 3.
The contrast accompanying drawing is explained most preferred embodiment of the present invention below.
Fig. 1 is a block diagram, shows the structure of the warning system of having used panalarm of the present invention.
Be arranged on the various sensors 6,6 on the precalculated position in the buildings under the monitoring ..., for example burglar alarm, the alarm of taking precautions against natural calamities etc. are connected with panalarm 4.In addition, 9 of telephone set 7 and facsimile recorders link to each other with telephone line 5 by panalarm 4.
When any sensor 6 output alarm signals were arranged in warning system shown in Figure 1, panalarm 4 was just reported to the police to central monitor 2.After receiving this alerting signal, central monitor 2 just is shown to the alerting signal of being sent out the staff in the Surveillance center 1.Surveillance center 1 is about to this alerting signal and circulates a notice of to standby station 10 according to its kind, and sends the guard in the buildings that detects alerting signal.
Send the guard who monitors this buildings with charge free and will further conclude security situation, and take the necessary measures as the case may be.
Fig. 2 shows the structure of the alert equipment 4 of contract quotation.
In the panalarm 4 of this embodiment, there is the decision circuit of opening circuit 21 to be plugged between alarm monitoring circuit 12 and the telephone line 5, be able to the interruption of the telephone line of detection alarm equipment 4 these sides.On this alarm monitoring circuit 12, be connected with various sensors 6,6 ... with facsimile recorder 9.
The decision circuit 21 that opens circuit is arranged to can be in the interruption of panalarm 4 one side detecting telephone circuits 5.The input end L1 of decision circuit 21 of opening circuit is connected with telephone line 5 with L2, and its output terminal L1 ' then links to each other with alarm monitoring circuit 12 with L2 '.One of input end L1 links to each other with one of output terminal L1 ' by the line current supervisory circuit, and another input end L2 then directly links to each other with another output terminal L2 '.Grafting one line voltage distribution supervisory circuit 23 between input end L1 and L2.The output signal of the output signal of line current supervisory circuit 24 and line voltage distribution supervisory circuit 23 is input among the CPU22.
The warning circuit 25 that includes hummer or flashing lamp is connected on the CPU22.Circuit in CPU22 and the alarm monitoring circuit 12 is connected circuit 13 and is linked to each other, exports the on-state that a command signal that is used for connecting this circuit is surveyed this circuit simultaneously.
Fig. 3 shows open-wire line road voltage monitoring circuit 23.
Between input end L1 and the L2 voltage by full wave rectifier D1 rectification and be resistor R 1 and R2 dividing potential drop.The voltage of power supply V1 then is resistor R 3 and R4 dividing potential drop.These two kinds of dividing potential drops all are input among the comparator C P1, and are controlled the on/off of a transistor Tr by the output of comparator C P1.Between transistor Tr and power supply V1, be connected with the photodiode PD1 of photo-coupler PC1.The phototransistor PT1 of photo-coupler PC1 then is connected with CPU22.
At this, when line voltage distribution was got stationary value, the output of comparator C P1 became L (low value), and transistor Tr disconnects.Phototransistor PT1 does not disconnect so there is electric current to flow through photodiode PD1.On the contrary, when line voltage distribution decline, the output of comparator C P1 becomes H (high value), and transistor Tr is connected, and phototransistor PT1 connects so there is electric current to flow through photodiode PD1.
Fig. 4 shows the structure of line current supervisory circuit 24.
The photodiode PD2 of photo-coupler PC2 is connected between input end L1 and the output terminal L1 '.The output terminal of phototransistor PT2 links to each other with CPU22.Now, when electric current flow through telephone line 5, phototransistor PT2 connected, and when this electric current did not flow through, phototransistor PT2 disconnected.
Below with reference to the open circuit work of CPU22 in the decision circuit 21 of process description shown in Figure 5.As noted earlier, this decision circuit 21 that opens circuit is that the interruption situation of telephone line 5 of detection alarm equipment 3 these sides of being used for is set.Survey the operation of the interrupt situation of Surveillance center's 1 this side telephone line 5, then undertaken by used same procedure in the alarm monitoring circuit 12 control prior art systems.
At first the step S1 in Fig. 5 judges whether telephone line 5 disconnects.The state of circuit connection circuit 13 in the alarm monitoring circuit 12 has been checked in this judgement.When the result proves denys (connection), and flow process proceeds to step S4, and works as it for being (disconnection), and flow process proceeds to step S2.
Monitoring circuit voltage in step S2.Check the state of the phototransistor PT1 of line voltage distribution supervisory circuit 23 at this.Because telephone line disconnects, if just circuit voltage surpasses a predetermined value can be judged to be normally, then be judged to be abnormality if be lower than this predetermined value under the state of step S2.In other words, when phototransistor PT1 disconnects, be judged to be normally, and flow process is returned step S1.If this transistor is connected, then judge this state abnormality, and flow process proceeds to step S3.
Exist because of noise makes condition judgement and be the unusual situation that does not in fact have interruption.So proceeding to, flow process is used for further determining the operations such as step S3 interrupted.
At step S3, CPU22 outputs signal to the circuit of alarm monitoring circuit 12 and connects circuit 13, and this telephone line is connection at alarm monitoring circuit 12 simultaneously.Point out in passing when this circuit is connected, can send a prearranged signals to Surveillance center 1 from panalarm 3 in case of necessity.
At step S4, the monitoring circuit electric current.Check the state of phototransistor PT2 in the line current supervisory circuit 24 at this.Because telephone line 5 is connected under the state of step S4, if surpassing a predetermined value, line current then is judged to be normally, be lower than this predetermined value and then be judged to be abnormality.In other words, then judge this state for normal when phototransistor PT2 connects, and flow process turns back to step S1.If this transistor PT2 disconnects, judge that then this state enters step S5 for the abnormality flow process.Owing to be that bigger electric current comes the monitoring circuit electric current when using than monitoring circuit voltage, the mistake that just can not take place to cause because of noise is judged.
At step S5, warning circuit 25 output alarm signals have been finished simultaneously and have been interrupted judging operation.As the output of reporting to the police, by the hummer sounding or lamp is glimmered realize that panalarm 3 these sides can determine that telephone line 5 interrupts then.
As mentioned above, when having the possibility of interruption, judge the existence of interruption subsequently by the monitoring circuit electric current by the judgement of monitoring circuit voltage.So,, also always can correctly judge the interrupt situation of telephone line even when when monitoring circuit voltage, having any false judgment because of noise.Because the monitoring of line current is just when circuit disconnects and survey line voltage distribution and just carry out when unusual, thereby can reduce the number of times of connection telephone line, can prevent to increase the operating cost of system thus.
In the above-described embodiments, the decision circuit 21 that opens circuit is independent of alarm monitoring circuit 12 and constitutes, and decision circuit 21 can be combined in the alarm monitoring circuit 12 but this opens circuit.
Contrast Fig. 6 illustrates a kind of improvement example of line voltage distribution supervisory circuit 24 below.
In Fig. 6, symbol C1 represents a capacitor, is used for gathering because of the mobile very little electric current of line voltage distribution.On capacitor C1, be connected with and be used for full wave rectifier D3, the constant voltage circuit CC1 of rectifying circuit voltage, phototransistor PT3 and the diode D4 of photo-coupler PC3, as charging circuit.At this, this constant voltage circuit CC1 includes transistor T R1, Zener diode ZD1 and resistor R 5, R6 and R7.In addition, on capacitor C1, be connected with the phototransistor PT4 of discharging resistor R8, photo-coupler PC4 and the optical diode PD5 of photo-coupler PC5, as discharge circuit.The photodiode PD4 of photo-coupler PC4 in the photodiode PD3 of photo-coupler PC3 and the discharge circuit in the charging circuit complies with alternately break-make of predetermined interval according to the control signal of CPU22.
When telephone line 5 do not interrupt and line voltage distribution just often, photodiode PD3 in the charging circuit connects, phototransistor PT3 also connects simultaneously.During this connected, capacitor C1 was by the very low current charge of the line voltage distribution that passes through resistor R 7.Secondly, the photodiode PD4 in discharge circuit connects, and when phototransistor PT4 connected then, capacitor C1 was promptly by discharging resistor R8 discharge.The photodiode PD5 that this discharge current is connected output optical coupler PC5 connects phototransistor PT5 simultaneously.
When detecting phototransistor PT5 in discharging time and connect (when phototransistor PT4 connects), CPU22 promptly judges and does not have interruption in the telephone line 5.On the other hand, when telephone line 5 interrupts, just do not have line voltage distribution.Therefore, even the photodiode PD3 in charging circuit connects, capacitor C1 does not charge yet, and makes output phototransistor PT5 disconnect when discharge.When CPU22 detects output phototransistor PT5 disconnection at discharging time, promptly judge to exist the possibility that opens circuit in the telephone line 5.Flow process promptly enters in the processing operation of step S3 among Fig. 5 etc., and verifies by line current.
Even when having a noise, The noise is also less than the influence of the discharge current of the capacitor C1 that is accumulating very little electric current.So,, simultaneously can further be reduced to the monitoring circuit electric current and connect the number of times of telephone line because of noise causes the possibility of line voltage distribution false judgment lessly.
When the state of telephone line becomes quite bad and noise often occurs on telephone line, may need frequently to carry out circuit and connect operation.At this moment to monitor by line voltage distribution supervisory circuit 26 by line current supervisory circuit 24 and judge the frequency that abnormality takes place, and when CPU22 judges that this occurrence frequency is very high, CPU22 just carries out control, makes the charge/discharge of the capacitor C1 of line voltage distribution supervisory circuit 26 become longer at interval.Above-mentioned occurrence frequency under this situation for example is to count by the number of times that this kind phenomenon is taken place to calculate, and when this counting for example surpassed 5 times in one hour, then the charge/discharge with capacitor C1 was reset at interval from 30 milliseconds to 1 second.
According to the present invention, in the frequent interruption situation of monitoring phone circuit of the panalarm that is used for reporting to the police to the destination.Can carry out relevant operation under the judgement situation that can not lead to errors in low cost simultaneously.
Claims (2)
1. be used for when detecting abnormality by telephone line the abnormality that is taken place being announced panalarm to intended destination, this equipment comprises:
The line voltage distribution supervising device is used at monitoring circuit voltage when described telephone line disconnects and surveys the abnormality of line voltage distribution;
The line current supervising device is used at monitoring circuit electric current when described telephone line is connected and surveys the abnormality of line current;
The circuit engaging means are used for connecting the DC circuit of described telephone line; And
Decision maker opens circuit, it is connecting described line voltage distribution supervising device, described line current supervising device and described circuit engaging means effectively, is used for short cause described circuit engaging means and connecting the DC circuit of described telephone line when described line voltage distribution supervising device detects abnormality, judge when described line current supervising device detects abnormality subsequently under the circuit on-state and have disruption in the described telephone line, export look-at-me simultaneously.
2. panalarm according to claim 1, wherein said line voltage distribution supervising device comprises:
Capacitor is charged by a line current when described telephone line disconnects;
Be used for giving the described capacitor device of charge and discharge repeatedly according to predetermined period; And
Be used for the device of when discharging time does not detect discharge current output alarm signal.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP248038/96 | 1996-09-19 | ||
| JP248038/1996 | 1996-09-19 | ||
| JP24803896A JP3544797B2 (en) | 1996-09-19 | 1996-09-19 | Error reporting device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1177160A CN1177160A (en) | 1998-03-25 |
| CN1119775C true CN1119775C (en) | 2003-08-27 |
Family
ID=17172279
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN97104584A Expired - Lifetime CN1119775C (en) | 1996-09-19 | 1997-04-02 | Alarm reporting apparatus |
Country Status (7)
| Country | Link |
|---|---|
| JP (1) | JP3544797B2 (en) |
| KR (1) | KR100668991B1 (en) |
| CN (1) | CN1119775C (en) |
| AU (1) | AU722707B2 (en) |
| MY (1) | MY125066A (en) |
| SG (1) | SG54475A1 (en) |
| TW (1) | TW322565B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4504241B2 (en) * | 2005-04-01 | 2010-07-14 | 株式会社ナカヨ通信機 | Automatic response detection method and automatic response detection device |
| JP6468064B2 (en) * | 2015-05-11 | 2019-02-13 | 株式会社リコー | COMMUNICATION CONTROL DEVICE, COMMUNICATION DEVICE, IMAGE FORMING DEVICE, COMMUNICATION CONTROL DEVICE CONTROL PROGRAM |
| US10382312B2 (en) * | 2016-03-02 | 2019-08-13 | Fisher-Rosemount Systems, Inc. | Detecting and locating process control communication line faults from a handheld maintenance tool |
| JP7527098B2 (en) * | 2019-03-29 | 2024-08-02 | 能美防災株式会社 | Fire Alarm System |
| CN110753163B (en) * | 2019-10-28 | 2021-05-18 | 上海市共进通信技术有限公司 | Protection device and method for VOIP functional module of optical network terminal |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5968096A (en) * | 1982-10-12 | 1984-04-17 | 東京綜合警備保障株式会社 | Disconnection monitor for subscriber's circuit |
| US4737776A (en) * | 1986-08-07 | 1988-04-12 | Wallace Wireman | Circuit for detecting cut telephone service line and transmitting signal over telephone trunk line |
| US4922529A (en) * | 1988-12-06 | 1990-05-01 | Kiel David J | Automatic hangup apparatus for restoring service to off-hook telephones |
| US4998271A (en) * | 1989-08-28 | 1991-03-05 | Venture Technologies, Inc. | Telephone accessory |
| JP2832196B2 (en) * | 1990-11-30 | 1998-12-02 | 群馬綜合ガードシステム 株式会社 | Telephone line disconnection detection device |
| JPH06223290A (en) * | 1993-01-26 | 1994-08-12 | Atsumi Denki Kk | Disconnection detection system and telephone equipment |
-
1996
- 1996-09-19 JP JP24803896A patent/JP3544797B2/en not_active Expired - Fee Related
-
1997
- 1997-03-06 SG SG1997000668A patent/SG54475A1/en unknown
- 1997-03-07 AU AU15139/97A patent/AU722707B2/en not_active Ceased
- 1997-03-08 TW TW086102847A patent/TW322565B/en not_active IP Right Cessation
- 1997-03-10 MY MYPI97000995A patent/MY125066A/en unknown
- 1997-04-02 CN CN97104584A patent/CN1119775C/en not_active Expired - Lifetime
- 1997-04-03 KR KR1019970012322A patent/KR100668991B1/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| JPH1097693A (en) | 1998-04-14 |
| JP3544797B2 (en) | 2004-07-21 |
| AU1513997A (en) | 1998-03-26 |
| TW322565B (en) | 1997-12-11 |
| KR100668991B1 (en) | 2007-05-14 |
| AU722707B2 (en) | 2000-08-10 |
| KR19980023992A (en) | 1998-07-06 |
| CN1177160A (en) | 1998-03-25 |
| SG54475A1 (en) | 1998-11-16 |
| MY125066A (en) | 2006-07-31 |
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| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
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Granted publication date: 20030827 |