JPS62128397A - Disconnection detection system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention connects a sensor that detects changes in physical phenomena such as fire or gas leaks, an alarm that issues an alarm, etc. to a repeater,
In a warning and alarm system that transmits detection information from sensors, etc. to a central receiver via the repeater, a relay that specifically detects disconnection of the signal line connecting the sensors, alarms, etc. connected to the repeater. The present invention relates to a disconnection detection system for a device.

(Conventional example) Conventionally, such a warning system has a configuration as shown in FIG.

For example, in a hotel or apartment complex, detectors 1 and 2 for detecting fire or gas leaks, alarm transmitters 3, alarm bells 4, etc. are installed at appropriate locations, and a receiver 6 is installed in the central storage room 5. By receiving detection signals from each sensor, etc., the system centrally monitors the presence or absence of abnormalities.

However, simply connecting the receiver 6 and a large number of sensors, etc. would require an extremely large number of signal lines, making construction difficult, so a common line method was adopted in which a small number of signal lines are shared for signal transmission. ing. According to this system, repeaters 78 to 7d connected in parallel to the common line 8 are provided, for example, on each floor, and dark corner sensors, etc. are connected to each repeater 7a to 7d, and from each sensor, etc. The detection signals are transmitted to the receiver 6 as unique and identifiable signals by the repeaters 7a to 7d.

By interposing a repeater in this way, it is possible to greatly improve the functions of warning and alarm systems for fires, gas leaks, etc.

(Problem to be Solved by the Invention) Here, since such a warning alarm system connects a plurality of sensors, alarm devices, etc. to a repeater, the signal line connecting these sensors and alarm devices, etc. The presence or absence of a disconnection directly affects the reliability of the entire warning and alarm system.

However, monitoring for disconnections in signal lines is an auxiliary function of the alarm system and is not necessarily its original function. Therefore, the processing time for monitoring disconnections can be reduced, and the processing capacity for alarms and anomaly alarms can be reduced. There is a demand for a disconnection detection system that can be inexpensive and ensure sufficient signal line reliability.

(Means for Solving the Problems) The present invention has been made in view of the above problems, and an object of the present invention is to provide a wire breakage detection system that can quickly and reliably detect wire breaks at low cost. As shown in the block diagram of FIG. 1, the configuration for achieving this purpose includes a control means 100 that sequentially performs each processing operation at a predetermined specific timing, and a control means 100 that sequentially performs each processing operation at a specific timing determined in advance, and a detection means 200 that detects a delay time between the process and the transition to the next process and outputs a predetermined signal within the delay time;
A disconnection detection means 300 is provided for detecting changes in the electrical state, ie impedance, etc. of the signal line 400 to be detected for disconnection during the period in which the signal is generated, and the The technical point is that the disconnection is detected during the idle time when the control means 100 does not operate on the external controlled means 500. Furthermore, in terms of specific technology, for example, in a system that uses a microcomputer as the control means and processes programs at predetermined cycle timing, disconnection is detected during idle time between the execution of one program and the execution of the next program. These are included in the present invention.

(Example) Hereinafter, an example of the disconnection detection system for a repeater according to the present invention will be described with reference to the drawings.

FIG. 2 shows a main part circuit showing a repeater of the disconnection detection system, which corresponds to the individual repeaters 7a to 7d shown in FIG. 8, and has connection terminals Vcc and Vs.

Vg is connected to the receiver 6 by connecting it in parallel to the common line 8.

On the other hand, connection terminals C and C are connection terminals for connecting the sensors 1, 2, etc. in FIG.
2 is connected.

A predetermined DC voltage is supplied to the connection terminal Vcc.

An address signal Sa for specifying only a specific repeater from multiple repeaters is transmitted from the receiver to the connection terminal Vs, and only the designated repeater transmits the detection signal from the sensor etc. to the receiver. In addition, when an abnormality occurs, a command signal is supplied from the receiver to an alarm device such as a bell to instruct it to ring.

The connection terminal vg is connected to the common ground line of the common line.

Power for operating the alarm device is supplied between the connection terminals VBB and VBC, and the alarm device BL is connected between the connection terminals 8B and 80.

That is, to explain the basic functions of the repeater shown in FIG. 2 using the flowchart shown in FIG. 3, first, an address signal Sa designating a specific repeater is transmitted from the receiver to the common line, When identifying the address as its own, the repeater returns the detection signal detected by each sensor to the receiver within a predetermined time.

Next, the sensor wire connecting the repeater and the sensor (the signal line La1Lb between the connection terminal 0 and 0 in FIG. 2) and the alarm device BL
Bell wires (signal wires Ic, d, m in Figure 2) to which are connected
e, IJ) is disconnected, and the series of operations of the designated repeater is completed.

Then, the repeaters designated by the other address signals operate in the same manner, and the presence or absence of an abnormality is sequentially transmitted from the plurality of repeaters to the receiver according to the instruction of the address signal.

As shown in FIG. 4, the address signal 3a is a rectangular signal string with a predetermined period. For example, the first rectangular signal specifies the first repeater, and the second rectangular signal specifies the second repeater. , Nth signals are mutually correlated so as to designate the Nth repeater, and each repeater recognizes that it has been designated by counting the number of rectangular signals generated. Then, the period until the next repeater is designated (from time 11 to t2 in the case of the first repeater)
period), the above signal transmission processing and disconnection detection processing are performed, and the results are transmitted to the receiver.

As shown in FIG. 5, the repeater divides the cycle period of the address signal 3a into seven processing periods (hereinafter referred to as states), and processes the detection from the sensor during the period from the first state to the fourth state. Processing is performed to transmit the signal to the receiver, and the fifth and sixth
Disconnection detection processing is performed during the state period. In this way, each repeater performs time-division processing, making it possible to send and receive signals using only a small number of common signal lines without causing interference with other repeaters. Furthermore, Figure 5 shows the first
Although the case of a repeater is shown, other repeaters operate similarly.

The repeater shown in FIG. 2 is configured under this system configuration.

10 is a microcomputer that controls the repeater, and 1. 2. 3. 4°K5. The own address is set by the switching means 11 connected to 6.

The microcomputer 10 has a sensor line 11. a.

The R-board is provided with an output terminal R2 that outputs a sensor line signal SC used for detecting disconnection of the wire 1b, and an output terminal R1 that outputs a sensor line signal 3C2. The microcomputer 10 also has a bell wire 11. Output terminal Q that outputs a bell wire signal sb used to detect disconnection of C-Lf
1 and a Q port having an output terminal Q2 that outputs a bell line monitoring signal 3b2, and an input port KO that inputs an address signal 3a.

As shown in FIG. 6, the connection terminal vS is supplied with a rectangular address signal 3a as a binary level voltage signal superimposed on the base voltage VΦ, and is connected to a resistor r1 and an NPN type transistor. Tr1 and Zener diode Z
Transistor Tr1 of the constant voltage power supply circuit composed of D1
From the emitter terminal of , a constant voltage V obtained from the base voltage VΦ
, is occurring. In addition, Zener diode ZD2
absorbs line noise applied to the microcomputer 10.

The light emitting diode LED driven by the NPN transistor Tr2 indicates the abnormality of the sensor line and the bell line as described above by the presence or absence of light emission.

A resistor r2. is connected between the connection terminals VCC and Vg. r19 and NP
An N-type transistor Tr3 is connected, and the transistor T
r3 is a PNP type transistor T according to the sensor line signal SC from the output terminal R2 of the microcomputer 10.
Drive control of r4. Transistor Tr4 is resistor r3
The resistor r4 is connected to the contact Ea through the emitter and the collector. Therefore, when the transistor l'-r4 is turned on, both ends of the resistor r4 are short-circuited.

The contact Ea has a resistor r5. r6. r7 and PNP type transistor Tr5. A variable current source circuit is constituted by Tr6, and is connected to a connection terminal C via a diode D1 and a Zener diode ZD3. A sensor, a transmitter, a terminator 12, etc. are connected in parallel between the connection terminals 1 and 0, respectively.

Further, the contact Ea is connected to the base contact of a PNP transistor Tr7 via a resistor r17, and the transistor l'
-r7 collector contact is resistor r8. It is connected to the ground connection terminal vg via r9, and the connection point Pa between the resistors r8 and 69 is connected to the base contact of PNP type transistors 1'-r8. The emitter contact of the transistor Tr8 is connected to the connection terminal VQ via the diode D2, and the collector contact is connected to the resistor r10. It is connected via r11 to the output side of a constant voltage circuit consisting of transistor Tr1 and Zener diode ZD1. Then, the transistor Tr2 is driven by a PNP type transistor Tr9 whose base contact is connected to the connection point of the resistors rlO and rll, so that the light emitting diode L
Controls ED light emission.

A resistor r12. is connected to the connection terminal VS via a Zener diode ZD4. r13 and NPN type transistor T r
A PNP type transistor Tr11 is connected to the collector contact of the transistor Tr10 via a resistor r20.
The base contact of the transistor Tr is connected to the resistor r14, and the transistor Tr
11 collector contacts are connected to the capacitor C1 and to the input port KO of the microcomputer 10. Here, the binary voltage signal shown in FIG. 6 supplied to the connection terminal VS is
Since the level is shifted by a predetermined voltage by the Zener diode ZD4 and supplied to the transistor Tr10, only the address signal Sa shown in FIG. 4 is supplied to the input port KO.

The output terminal Q1 of the microcomputer 10 is connected to the base contact of an NPN transistor Tr12, and a photocoupler (light emitting diode Dh1 and phototransistor T
(consisting of rhl) drives the light emitting diode D of PH1.

Further, the output terminal Q2 is connected to one input terminal of the NAND circuit N1, and the output terminal of the NAND circuit N1 is connected to the diode D.
3, and the other input terminal is connected to the output contact Eb of the phototransistor T rh2 of the photocoupler PH2 (consisting of a light emitting diode Dh2 and a phototransistor T rh2) through the output terminal of the inverter circuit IV. is connected to.

Further, the output terminal R1 is connected to the contact Pa via a diode D4.

The circuit for activating the alarm device BL is the connection terminal VBB,
It is configured between VBC. That is, connection terminal V8B.

Diodes D5.VBC and diodes D5. D6 are connected, and the respective common contacts are resistors r15. r16 is connected to the connection terminal BC via the phototransistor T rhl of the photocoupler PH1 and the light emitting diode Dh2 of the photocoupler PH2, and both ends of the resistor r16 are connected to the connection terminal BC via the capacitor C2 and the Zener diode ZD5.
Connect to.

Further, a diode D7 is interposed between the connection terminals VBB and 88, a diode D8 is interposed between the connection terminals MBC and BC, and a changeover switch S driven by a relay (not shown) is connected to the diode D7.
W is provided, and a diode D is provided in parallel with the alarm device BL.
9 is connected with reverse bias. Although not shown, the repeater is provided with a signal detection means for detecting a command signal for driving the bell supplied from the receiver via the connection terminal VS. When current is supplied to the relay, the changeover switch SW closes and the connection terminal VB
The current from B is passed through the switch SW to the alarm device BL.
It is designed to make a sound by supplying it to the

Note that normally, the connection terminal VBB has a positive potential, and the connection terminal V
When a negative potential power source is supplied to BC and a disconnection of the bell wire is detected (during state 5.6 in FIG. 5), a voltage of opposite polarity is applied.

Next, the operation of each part of the system with this configuration will be outlined.

First, the operation in which the repeater transmits a detection signal from a sensor or the like in response to the address signal 3a from the receiver, that is, the operation in the period from state 1 to state 4 in FIG. 5 will be described.

Address signal S from the receiver supplied to connection terminal VS
a is Zener diode ZD4, transistor TrlO
, Trll, etc. to generate an address signal Sa of a predetermined rectangular waveform.
When the microcomputer 10 recognizes that the count value of the address signal 3a is equal to the own address set by the switching means 11, the address signal 3a is waveform-shaped and input to the input port KO of the microcomputer 10, as shown in each state of FIG. Start processing.

As shown in (A> to (E) in FIG.
, output terminal Q2 outputs “L pt level signal Sb2, output terminal R1 outputs “High level signal 3” only in state 4.
c2 is output.

Since the transistor lr3.Tr4 is turned on by the H1 rubel signal R2 from the output terminal R2, both ends of the resistor r4 are short-circuited during this period, and the connecting terminal Vc
A resistor r3 is interposed between the contact point Ea and the contact point Ea. Further, the output contact Pb of the NAND circuit N1 becomes the Hpt level due to the LIT level signal Sb2 from the output terminal Q2, so the diode D3 is reverse biased and becomes substantially open. Furthermore, when the signal SC2 from the output terminal R1 goes to the "H" level (in state 4), diode D4 becomes open, and together with the open state with diode D3, in state 4, the NAND circuit N1 and output terminal R1 are cut off from the common contact pa of resistors r3 and r9.

Here, if any of the sensors connected to the connection terminal RI or C detects an abnormality, the impedance between the connection terminal RI and 0 becomes low and the current in the sensor wires n, a, and Lb increases.
A voltage drop corresponding to the current increase occurs across the resistor r3. This voltage drop is caused by transistor Tr7. Tr8. An increased current flows through Tr9 and is supplied to transistor Tr2,
As the impedance between the collector and emitter of the transistor Tr2 decreases, the current flowing through the connection terminal S increases. By detecting this increase in current, the receiver can identify that the sensor belonging to the addressed repeater has detected an abnormality.

Note that the receiver performs this identification at the timing of state 4. That is, as mentioned above, the signal 3c2 at the "Hto level" is output from the output terminal R1 of the microcomputer 10 during state 4, the diode D4 becomes open, and the transistor Tr8 is turned on.

On the other hand, when neither sensor detects an abnormality, there is no low impedance between the connection terminal and 0, so the resistance r
3, the voltage drop does not increase, and therefore the transistor Tr7
is turned off, and the transistors Tr8°Tr9. Since Tr2 is also turned off, there is no increase in the current flowing through the connection terminal VS, and the receiver can identify that there is no abnormality.

Next, the disconnection detection operation in states 5 and 6 will be explained. First, the operation of each circuit will be outlined.

During this period, as shown in (A) to (E) in FIG. 7, "L pt
level signal SC1 output terminal Q1 outputs “Htt level signal sb” output terminal R1 outputs 141 P in state 5.
t, in state 6, signal 3C2 of "H19 level" is output, and furthermore, the signal 3C2 at the start of state 6 is output from output terminal Q2 (
From time ts5), a signal Sb2 at the H99 level with a predetermined delay time τ is output.

This delay time τ is caused by the microcomputer 10 outputting the signal SC2 from the output terminal R1 of the R port, and then outputting the signal Sb2 from the output terminal Q2 of the Q port. Since the microcomputer 10 operates with independent and separate programs, the time difference between when the microcomputer 10 performs program processing for specifying the R port and then performs program processing for specifying the Q port becomes the delay time τ. When the transistors Tr3 and Tr4 are turned off by the "L P9 level signal 3c from the output terminal R2, the resistor r4 is connected in series with the resistor r3.

Although not shown, when detecting disconnection, connect terminal VBB.
, reverse polarity to MBC, that is, negative to connection terminal VBB,
Power with a positive potential is supplied to the connection terminal V13C.

Furthermore, in state 5, the "11 rubel signal SC2 is output from the output terminal R1 of the microcomputer 10, and the diode D4 becomes forward biased, so that the contact Pa
Since the potential of the transistor l is at the "L tt level,"
r8 cannot be turned on, and transistor Tr2 is also always turned off. That is, as will be described later, in states 5 and 6, when the signal 3c2 at the "H" level is output from the output terminal R1 (state 6), it is determined whether or not there is a disconnection.

Next, the sensor lines 1a, 1. If R3.b is not disconnected, the current for driving the sensor flows between the connecting terminal and R3. A transistor Tr7 is connected to both ends of r4.
A forward bias voltage sufficient to turn on the transistor Tr7 is generated, and as shown in FIG. 7(F), the transistor Tr7 enters state 5.
, 6 is turned on.

On the other hand, if the sensor wires 1a and lb are disconnected, there will be high impedance between the connecting terminals and 0, and a voltage sufficient to turn on the transistor Tr7 will not be generated across the resistors r3 and r4, as shown in FIG. 7(G). As shown in , the transistor T
r7 is turned off and the collector-emitter becomes high impedance.

Next, if the bell wires 1C to Lf are not disconnected, the transistor Tr12 is turned on by the "H" level signal sb from the output terminal Q1 of the microcomputer 10, and the light emitting diode D emits light. The phototransistor T rhl is turned on, and the light emitting diode D is turned on.
h2 emits light, turning on the phototransistor T rh2, and as shown in FIG. 7 (H>), the potential at the contact Eb becomes Hto level.

That is, when detecting a disconnection, since a negative potential is applied to the connection terminal V13B and a positive potential is applied to the connection terminal MBC, d(H1
When the phototransistor Trh1 is turned on due to light emission from the light emitting diode D driven by the e-level signal sb, the current from the connection terminal VBC flows through the diode D6. Resistance r15. r16. It passes through the phototransistor 1rhl, the light emitting diode Dh2, and further the diode D9. The light flows to the connection terminal VBB via D7, and the phototransistor T rh2 is turned on by the light emission from the light emitting diode Dh2.
The contact Eb has a potential at the "Hme level."

On the other hand, if the bell wires fJ, c-Lf are disconnected, even if the "H" level signal sb from the output terminal Q1 of the microcomputer 10 turns on the transistor Tr12 and the light emitting diode Dhl emits light, Bell wire 1), C
- Since the phototransistor T rhl and the light emitting diode Dh2 cannot pass current due to the disconnection of ALf, the photo transistor T rh2 is turned off, and as shown in FIG.
As shown in >, the potential of the contact Eb is at the "L It" level.

Next, the wire breakage detection operation according to the state of wire breakage will be described in detail based on FIGS. 7(J) to (M).

1", the case where none of the sensor wires 11a, lb and the bell wires fJ, C-Lf are disconnected will be explained based on FIG. 7 (J). In FIG. 7 (D>, (E)) As shown, the "HfF level signals SC2, 3b2 are output from the output terminals R1, Q2 of the microcomputer 10 with a predetermined delay time τ, and the "HfF level signal SC2, 3b2 is output from the output terminal R1.
diode D4 turns off, and the NAND circuit N1 closes contact E due to the Htt level signal from output terminal Q2.
In combination with the “H9t level voltage” of “b”, the output contact Pb “
The diode D3 is turned off by outputting the H'' level.

At this time, the transistor Tr7 is turned on and the contact Pa is "H".
Since the potential is 1 level, the transistors Tr8. T
r9. Tr2 is turned on and the light emitting diode LED emits light, indicating that there is no disconnection.

Next, there is no disconnection in the sensor wires 1a, 1) and b, and the bell wire L
The case where there is a disconnection in C, L( will be explained based on FIG. 7 (K). If there is a disconnection in the bell wires Q, C, Lf, the
As shown in I), the potential at the contact Eb becomes "L tp level." Here, the diode D4 is turned off by the "H99 level signal 3c2 from the output terminal R1 of the microcomputer 10, and then the diode D4 is turned off after a predetermined delay. Output terminal Q at time τ
2, when the signal Sb2 of "Hpp level" is output, the NAND circuit N1 becomes "L" of the contact Eb only during the delay time τ.
Together with the "H99 level voltage, a signal at the H99 level is output to the output contact Pb, and the diode D3 is turned off.

During this period τ, since the transistor lr7 is on, the contact Pa becomes the HIf level, and the transistor Tr8
．． Tr9. Tr2 turns on and light emitting diode LED
emits light. However, since the light emitting time is short (τ), the brightness will be darker than when there is no disconnection at all. You can identify if there is.

Next, the sensor line fLa, 11. There is a disconnection in b, and the bell wire 1111. Figure 7 (L) shows the case where there is no disconnection in C-1f.
The explanation will be based on. Sensor line 11. When a and ILb are disconnected, the transistor T
r7 is turned off, the signals 3c2 . Regardless of the voltage level of Sb2, contact pa always has a potential of "L pt level", transistors Tr8, Tr9, and Tr2 are turned off, and the light emitting diode LED does not emit light.

A case where both the sensor wires ia and ib and the bell wires LC to f are disconnected will be described with reference to FIG. 7(M). When the sensor lines Ia, lb are disconnected, the transistor Tr7 is turned off as shown in FIG. 7(G), so that the signals 3c2. Regardless of the voltage level of Sb2, the contact pa always has a potential of the "199 level", and the potential of the transistors Tr8.
Tr9. Tr2 is turned off and the light emitting diode LED does not emit light.

In this way, since the microcomputer 10 sequentially performs program processing during the period of state 6, the signals Sc2. By taking advantage of the fact that Sb2 is not output and therefore a predetermined delay time τ occurs, "Hpe
Since a level signal can be generated and this signal can be used to detect disconnection of the bell wire, the processing efficiency of the microcomputer 10 can be improved by detecting disconnection between each program processing of the microcomputer 10. can do.

Also, if this delay time τ is not used, Fig. 7 (J)
, (L), (M>), there are two types of light-emitting diode detection: one in which both the sensor wire and the bell wire are normal, and one in which there is a disconnection in either the sensor wire or the bell wire. It is only detected by whether or not the LED is lit. Therefore, if the light emitting diode LED goes out, it is not possible to recognize whether the sensor wire or the bell wire is disconnected. For example, as shown in Figure 7 (K), by using the delay time τ, it is possible to additionally display the case where there is no abnormality in the sensor wire and a break in the bell wire has occurred. , Therefore, it becomes easy to check the failure location, and it is possible to shorten the time for failure analysis and improve maintenance work.

In this embodiment, the idle timing (delay time) of program processing is detected by outputting signals from different output ports of the microcomputer, but other timings may also be used.

Further, the control means is not particularly limited to one using a microcomputer, as long as the control means performs processing sequentially at a predetermined timing.

(Effects of the Invention) As explained above, according to the present invention, the control means that sequentially performs each processing operation at a predetermined specific timing finishes one processing and then moves to the next processing. Since the detection means for detecting the delay time between the above and the above is provided, and the disconnection is detected within the delay time detected by the detection means, the processing ability of the control means can be improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an overview of the configuration of the present invention, FIG. 2 is a circuit diagram showing an embodiment of the disconnection detection system according to the present invention, and FIG. 3 is a flowchart showing the basic operation of FIG. 2.
Fig. 4 is a timing chart showing the signal transmission method shown in Fig. 2, Fig. 5 is a timing chart showing the internal processing timing shown in Fig. 2, and Fig. 6 is a waveform diagram showing the address signal transmission method shown in Fig. 2. , FIG. 7 is a timing chart explaining the disconnection detection operation of FIG. 2, and FIG. 8 is a block diagram showing a conventional example. 10: Microcomputer R1, R2, Ql, Q2: Output terminals ILa, Ib: Sensor lines Lc, ld, ILe, Lf: Bell wires Tr3. Tr
4. Tr7. Tr8. Tr9. Tr12: transistor r3. r4. r8. r9. rlO, rll: resistance D2.
D3. D4: Diode PH1, PH2: Photocoupler LED, Dhl, Dh2: Light emitting diode Trhl,
Trh2: Phototransistor N1 NAND circuit Iv: Inverter 100: Control means 200: Delay time detection means 300: Disconnection detection means 400: Test signal line

Claims (1)

[Claims] A control means that sequentially performs each processing operation at a predetermined specific timing, and detects a delay time between the end of one processing and the transition to the next processing. , a disconnection detection device comprising: a detection means for outputting a predetermined signal within the delay time; and a disconnection detection means for detecting the electrical state of the signal line to be detected for disconnection within the period in which the signal is generated. system.