JPH0452519B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a plurality of photoelectric smoke detectors that output analog signals according to detected smoke concentration, and a signal line voltage level or The present invention relates to a fire alarm system in which a general type sensor that outputs a level signal with a variable current level is connected to a signal line derived from a receiver.

[Background technology]

Conventional optical smoke detectors of this type are equipped with an optical system, so if dirt etc. become worse over time, the output level when the smoke concentration is zero, that is, the zero level, will fluctuate, resulting in There was a problem with issuing false alarms.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned problems, and its purpose is to automatically correct zero level fluctuations caused by dirt in the optical system, and to automatically correct zero level fluctuations caused by dirt on the optical system. To provide a fire alarm system capable of notifying a functional outage by generating power to detect a functional outage.

[Disclosure of the invention]

The present invention will be explained below with reference to Examples. FIG. 1 shows a basic schematic configuration diagram of a fire alarm system using one embodiment, in which a signal line L derived from a receiver 1 includes an intelligence type smoke detector 2 and a general type smoke detector 3a. and a heat sensor 3b are connected together. The receiver 1 transmits a transmission signal consisting of a pulse code signal including an address signal individually assigned to each intelligence type smoke detector 2.
V _S is superimposed on the line voltage or current of the signal line l as shown in Fig. 2, and sent cyclically and sequentially, and the information sent as a return signal from each called intelligence type smoke detector 2 is determined. At the same time, by monitoring the line voltage and line current level of the signal line l, the general smoke detector 3
Level signal V _L from a or general type heat sensor 3b
It is possible to carry out various control operations such as receiving data.

The intelligence type smoke detector 2 can each have its own address set, and when the address signal included in the transmission signal V _S sent out from the receiver 1 matches the self-set address, the transmission signal V _S and the next transmission Various information is superimposed and sent back to the receiver 1 as a pulse code signal during the return period provided between the signal VS and the signal _VS. When the general type smoke detector 3a or heat sensor 3b detects a predetermined smoke concentration or temperature, it turns on and short-circuits the signal line l through an appropriate resistor to change the level of the line current or line voltage, etc. The fire detection signal is transmitted to the receiver 1 as a signal _VL .

During normal operation, the receiver 1 sequentially calls each intelligence-type smoke detector 2, receives information from each intelligence-type smoke detector 2, and makes judgments, and also checks the voltage or current level of the signal line 1. By detecting, the operation of the general type smoke detector 3a or heat sensor 3b is monitored, and the steady line voltage or line current by the terminator 4, such as the resistance of the signal line l, is detected and the signal is detected. It monitors the line l for short circuits and disconnections.

Next, the specific configurations of the receiver 1 and the intelligence type smoke detector 2 will be explained.

The receiver 1 is a basic unit 1 as shown in FIG.
A and an extension unit 1B, and the extension units 1B can be combined as necessary.

The basic unit 1A has a coupling circuit section 5 for interfacing with the signal line 1, and from the line voltage extracted by the coupling circuit section 5, the general smoke detector 3
a or the level signal V _L of the heat sensor 3b, and the short circuit.
A level detection circuit section 6 that discriminates voltage levels from disconnections and a pulse code signal, which is a return signal received and extracted via the coupling circuit section 5, is demodulated and is connected to the signal line l via the coupling circuit section 5. A transmission signal modulation/demodulation circuit unit 7 modulates and creates a transmission signal V _S to be superimposed by using the level detection information discriminated by the level detection circuit 6 and the level detection information from the intelligence type smoke detector 2 demodulated from the transmission signal modulation/demodulation circuit unit 7. A function that reads the information and determines whether a fire has occurred, or identifies the location where a fire has occurred, or whether the signal line 1 is disconnected or short-circuited, or whether there is an abnormality in the smoke detector 2. Furthermore, based on these judgment results, the I/O interface 11 displays a fire area display corresponding to the signal line, a fire alarm, a warning, a warning for the area, a sensor abnormality display, a signal line abnormality display, The smoke exhaust system generates control outputs such as controlling the fire extinguishing system, sends and receives information to and from the expansion unit 1B through the interface 9, and further creates pulse code signals for sequentially calling the intelligence type smoke detector 2. an arithmetic signal processing circuit section 8 consisting of a CPU, etc., which performs control signal processing such as sending the transmitted signal to the transmission signal modulation/demodulation circuit section 7;
, a storage section 10 that stores and holds settings for control operations of the arithmetic signal processing circuit section 8, a keyboard 12, and the like. On the other hand, the amplification unit 1B is capable of transmitting and receiving data to and from the basic unit 1A via the interface 13, and has a combination table of predetermined sensors and corresponding external equipment such as fire extinguishing equipment and smoke prevention equipment. and a storage section 14 storing combination data for setting the combination of the relay means and the number of the signal line l to which it belongs when a relay means is provided, the data from the basic unit 1A, and the storage section 14. Selection control of smoke prevention equipment, etc. to be controlled from the setting contents, display of the operating status of each sensor, display of the operating status of the relay means by displaying the number of the signal line l corresponding to the relay means, and furthermore, display of the operating status of the relay means, etc. Control operations that perform interlocking displays that display the operating status of smoke prevention devices, etc., and keyboard 1
5, a keyboard 15 and a display; The basic unit 1A is equipped with an I/O interface 18 that interfaces the unit 17 and the arithmetic signal processing circuit unit 16.
The basic unit 1A generates control outputs for smoke prevention devices and the like. Of course, the smoke prevention device and the like may be controlled by the extension unit 1B. Note that 13' is an interface for expansion.

As shown in FIG. 4, the intelligence type smoke detector 2 has a body composed of a base 2a and a head 2b, and has an internal circuit as shown in FIG. In other words, inside the head 2b are a light beam type smoke detection section 19 for detecting smoke, and a smoke detection section 1.
Zero level shift circuit section 20 that constantly detects the zero level of No. 9 and performs shift control to stabilize the zero level.
, an output circuit section 21 that outputs an analog signal according to the smoke concentration detected by the smoke detection section 19, and a zero level shift circuit section 20 detect whether or not the range in which the zero level is shifted exceeds a predetermined range. a self-check circuit section 23 for detecting a function, and a function failure determination circuit section 22 for determining that the function has stopped and generating an "H" signal when the self-check circuit section 23 outputs a detection signal indicating that the above-mentioned predetermined range has been exceeded. It is equipped with On the other hand, the base 2a is used to removably mount the head 2b, supply power to the circuit inside the head 2b, and connect the output of the output circuit section 21 and the output of the malfunction determination circuit section 22. It is installed on the mounting surface of the output circuit section 21, and includes a level discrimination circuit section 24 for discriminating the analog signal from the output circuit section 21 into, for example, three levels and outputting three levels of smoke concentration data; The output data from the function stoppage determination circuit section 22 is taken in and sent as return information to the receiver 1, and a return signal consisting of a pulse code signal based on the information is created. When the address signal and the address signal included in the transmission signal V _S transmitted from the receiver 1 via the signal line l match, the receiver 1 included in the transmission signal V _S
The arithmetic signal processing circuit 26 is connected to the signal line l, which performs signal processing such as taking in information from the transmission signal V _S and transmitting the return signal during the return period following the transmission signal V _{S .} A coupling circuit unit 27 for extracting the signal or superimposing a return signal on the signal line l, and obtaining power through the coupling circuit unit 27, and also detecting a set level with a high smoke density by level discrimination by the level discrimination circuit unit 24 described above. In other words, when low-sensitivity detection continues for a predetermined period of time, the signal line l is short-circuited through an appropriate resistor, and the line voltage level, current level, impedance, etc. signal
A fail-safe circuit section 28 for sending V _L through the coupling circuit section 27, and when the sensor functions as an intelligence type or outputs only a level signal similar to a general sensor and also outputs a level signal. In other words, it is equipped with a type/application setting unit 29 for selecting and setting whether to function as a so-called point address type that transmits a pulse code signal corresponding to its own address to the receiver 1 when a fire is detected, and the above-mentioned three-stage smoke Concentration discrimination corresponds to type 1, type 2, and type 3 of smoke detectors, for example, 5%, 10%, and 15%, and when each level is exceeded, a corresponding detection signal is generated. It is.

Now, in the receiver 1, the keyboard 12 is stored in the storage section 10.
This allows the following operating conditions to be set. First, in this system, fire occurrence is determined by the level signal V _L from the general smoke detector 3a and heat sensor 3b.
In addition, the smoke concentration from the intelligence type smoke detector 2 is used in combination with a time function, and on the receiver 1 side, the keyboard 12 corresponds to each intelligence type smoke detector 2. The detected smoke concentration, which is a condition for fire occurrence determination, and the duration of the detected smoke concentration can be selected and set. In other words,
The detected smoke concentration data returned from the intelligence type smoke detector 2 has three stages, and there are two types of time, for example 6 seconds and 30 seconds, and one of these detected smoke concentrations and one of the times are This allows fire sensitivity settings to be made using two functions: smoke concentration and time. This setting condition is determined depending on the installation location of each intelligence type smoke detector 2.

In addition, the receiver 1 has a logical product alarm function that generates a control output for controlling smoke prevention equipment, fire extinguishing equipment, etc., when each of the multiple intelligence smoke detectors 2 reaches the fire occurrence determination condition. The address table of combinations of the intelligence type smoke detectors 2 can be set and stored in the storage section 10 using the keyboard 12 in order to issue a logical AND alarm. Furthermore, the receiver 1 is capable of issuing a warning that requires attention, and an address table in which each intelligent smoke detector 2 that requires a warning is selected is displayed on the keyboard 1.
2 allows settings to be stored in the storage unit 10.

As shown in FIG. 2, the receiver 1 superimposes the transmission signal V _S on the line voltage of the signal line l in the order of the addresses set by the storage unit 10 and sequentially transmits the signal cyclically. The type smoke detectors 2 are called and the information on the detected smoke concentration and the monitoring information on the malfunction of each smoke detector 19 are sent from each smoke detector 2 as a return signal. Check the condition.

Now, when the receiver 1 receives a return signal from the intelligence type smoke detector 2 at the predetermined address, the arithmetic signal processing circuit unit 8 detects the fire occurrence of the intelligence type smoke detector 2 stored in the storage unit 10. The detected smoke concentration for judgment is compared with the detected smoke concentration data in the return signal, and if the detected smoke concentration data is smaller than the set detected smoke concentration, the arithmetic signal processing circuit section 8 determines that no fire has occurred. be. Conversely, if the detected smoke concentration is higher than the detected smoke concentration, the set time is counted by the fire determination timer. The built-in timer continues counting as long as the above-mentioned cyclic calls are repeated and the returned detected smoke concentration data does not fall below the set detected smoke concentration. If it is determined that the set time has elapsed, it is determined that a fire has occurred, and the fire is reported by the bell 31 or the like. By the way, if the intelligence-type smoke detector 2 is set as a target for issuing a caution alarm, first compare the detected smoke density data with the smoke density that is one level lower than the set detected smoke density, and make a judgment based on this comparison. If the detected smoke concentration data is lower, it is determined that there is no need to issue a caution warning. On the other hand, if the value is high, a caution warning timer starts counting for a predetermined period of time. The above-mentioned cyclic calls are repeated until the returned detected smoke concentration data does not fall below the set detected smoke concentration.
The caution warning timer count continues. If the detected smoke concentration data does not fall below the next lower level of the set detected smoke concentration until the time of count-up, the arithmetic signal processing circuit section 8 determines that caution is required, and issues a warning requiring caution as a preliminary warning.

By the way, if the detected smoke concentration data exceeds the set detected smoke concentration during the count period of the caution alarm timer, the fire judgment timer starts counting.
The above-mentioned fire occurrence determination is performed. When the detected smoke density data falls below the set detected smoke density while the fire judgment timer is counting, the count time up to the time of the drop is memorized and added, and the count of the fire judgment timer is reset. If the addition result is less than the predetermined time corresponding to the need for caution, the process returns to the counting routine of the timer for the caution need warning. When the above-described added value of the period in which the detected smoke concentration data exceeds the set detected smoke concentration reaches a predetermined time or more, the arithmetic signal processing circuit section 8 determines that caution is required, and issues a warning that caution is required.

Now, when determining the occurrence of a fire as described above, it is also determined at the same time whether or not the intelligence-type smoke detector 2 is set to issue an AND alarm, and if not, a fire alarm is received. Machine 1
will be notified. In addition, if the device is set to issue a logical product alarm, whether or not other intelligence-type smoke detectors 2 set in combination with the intelligence-type smoke detector 2 are also determined to have caused a fire. If the judgment is ``YES'', the receiver 1 issues a fire alarm. When it is determined that a fire has occurred, the receiver 1 outputs a control signal to the smoke prevention device, fire extinguishing device, etc. that are set to be linked in advance to the intelligence type smoke detector 2, and activates each device. The display sections 17, 17' display information indicating which sensors and devices are in operation, and also display fires by district.

Although it is preferable to set the above-mentioned caution alarm setting for all intelligence type smoke detectors 2, this does not apply when the smoke density and time settings are set to low sensitivity. Further, it may be determined that a fire has occurred when at least two of the smoke detectors 2 connected to the same signal line 1 issue a warning requiring attention.

In addition, the AND alarm is issued when it is determined that a fire has occurred in all of the combined all-intelligence type smoke detectors 2, and for example, in a computer room, library, or other area where valuable items are installed or stored. Of course, a priority determination function may be provided to determine the occurrence of a fire at that point when the installed intelligence type smoke detector 2 determines that a fire has occurred first or during the process. Further, the logical product alarm may be used for interlocking operation with the smoke prevention device and the fire extinguishing device, and the occurrence of a fire may be alarmed when each smoke sensor 2 determines the occurrence of a fire.

FIG. 6 shows a flowchart of the arithmetic signal processing circuit unit 8 related to the above-described fire occurrence determination and caution warning warning determination, and FIGS. 7 a to 7 d show comparative operations of fire occurrence determination and caution warning warning determination The graph shows the relationship between the density of smoke detected by the intelligent smoke detector 2 and the smoke concentration detected by the intelligent smoke detector 2. Figure 7a shows the three levels of detected smoke concentration set in the figure. This shows a state in which occurrence determination is made. Figure 7b shows that the time the set level is exceeded is shorter than the set time T〓.
and a predetermined time period for determining the level that requires attention, when the time exceeds the next level lower level for determining the level that requires attention.
A state shorter than T〓, that is, a state that is determined to be a temporary state due to disturbance etc., and a state in which neither a fire alarm nor a warning requiring attention is issued. Fig. 7c shows a condition in which the level has continued for more than a predetermined time T〓, that is, there is either a fire or a setting failure.
Indicates a state in which it is determined that it is necessary to issue a caution warning. In addition, Fig. 7 d shows a state in which the detected smoke concentration intermittently exceeds the set level and the total exceeding time exceeds the predetermined time T〓.
Similar to FIG. c, this shows a state in which it is determined that it is necessary to issue a caution warning.

By issuing the above-mentioned caution warning, setting errors can be easily discovered, the setting sensitivity of each smoke detector 2 can be calibrated after the system is installed, and the system can be optimized without false alarms. be.

By the way, the fire sensitivity level shift shown in the flowchart of FIG. It's summery. In other words, for example, if the standard sensitivity is a combination in which the setting time is 6 seconds and the detected smoke density is 10%, the sensitivity of the intelligence type smoke detector 2, which is set at a lower sensitivity than this standard sensitivity, will be one step higher. As such, the arithmetic signal processing circuit unit 8 switches either or both of the set time and the set detection smoke concentration corresponding to the target intelligence type smoke detector 2 for the set fire sensitivity level shift when determining the occurrence of a fire. . Therefore, simultaneously with the fire occurrence determination, the fire detection sensitivity corresponding to the target intelligence type smoke detector 2 increases, making it possible to quickly detect the state of fire spread.

By the way, there are cases where it is desired to change the fire detection sensitivity corresponding to each intelligence-type smoke detector 2 depending on changes in the environment and management conditions, such as during the day and night, when there are people and when there are no people, but this system does not. The arithmetic signal processing circuit section 8 is provided with a sensitivity level shift function for switching the sensitivity of the intelligent smoke detector 2 selected and set by a command input from the keyboard 12 or by a command automatically added at a preset time. I have it. In other words, during the daytime or during manned periods, you can switch to low sensitivity when malfunctions such as cigarette smoke are likely to occur, or conversely, set it to high sensitivity during the daytime or during manned periods, where you can deal with false alarms, and then set it to high sensitivity at night or during unmanned periods. It is set to the resistance level. In this case, the sensitivity changing element may be programmed to switch the set time to the long time side, or to set the set detected smoke concentration one step lower if the set time is set to the long time side.

Furthermore, in this system, external equipment such as a fire extinguishing device and a smoke prevention device are provided that are linked to a predetermined smoke detector 2, and when a fire occurrence is automatically determined by the corresponding smoke detector 2, It is equipped with an interlocking function that operates compatible external devices, but when you set an instruction for a linked smoke detector 2 from the keyboard 12, the setting sensitivity corresponding to the smoke detector 2 is automatically switched to the low sensitivity side. Equipped with a linked level setting function.

Now, as described above, when the receiver 1 issues a fire outbreak or warning warning, alarm confirmation information is sent as a transmission signal V _S to the smoke detector 2 from the receiver 1 at the next access. When the smoke detector 2 receives this information, the arithmetic signal processing circuit section 26
The light emitting diode 30 is turned on by the function of the light emitting diode 30 to display the operation. This display makes it easy to determine whether the system functions are operating normally during test operations during construction maintenance. Now, the intelligence type smoke detector 2 which has received the alarm confirmation information controls the operation of the fail safe circuit section 28 so as to stop outputting as a general type smoke detector which is a backup function.

Next, the operation of the intelligence type smoke detector 2 will be explained. The smoke detection section 19 of the smoke detector 2 detects that the light emitted from the light emitting section 19a is scattered or blocked by smoke and is received by the light receiving section 19b, and detects the amount of light received, that is, smoke. Zero level shift circuit section 20 converts the analog signal according to the concentration.
This is generated via the output circuit section 21. The analog signal outputted from this output circuit section 21 is discriminated by the level discrimination circuit section 24 into the above-mentioned three stages of detected smoke concentration levels, and the discriminated data is taken into the arithmetic signal processing circuit 26. Based on this, the detected smoke concentration data is sent back to the receiver 1 via the coupling circuit section 27. Of course, the analog signal may be A/D converted without discrimination, and the raw data of the detected smoke concentration may be returned. If there is a detection corresponding to the low sensitivity discriminated by the level discrimination circuit section 24, the fail-safe circuit section 28 counts this detection period using a built-in timer, and when a predetermined time period is exceeded, short-circuits the signal line l via a resistor. The level signal V _L similar to that of a general type sensor is output from the coupling circuit section 27, so that even if the arithmetic signal processing circuit 26 using the CPU causes trouble due to noise etc., the arithmetic signal processing circuit section 26 The smoke detection signal can be generated regardless of the operation of the detector, and the so-called backup function can be achieved. Of course, if the arithmetic signal processing circuit 26 is normal and returns the detected smoke concentration data, the output of the smoke detection signal from the fail-safe circuit section 28 is determined by the alarm confirmation information from the receiver 1 as described above. It's starting to get shut down. The fail-safe circuit section 28 is configured such that the level discrimination circuit section 24 is provided with a discrimination function for the fourth stage high smoke concentration detection level, and is activated when the level discrimination circuit section 24 detects this high smoke concentration. Of course it's fine.

The zero level shift circuit section 20 is a circuit for correcting the zero level that occurs when the optical system section 19c of the smoke detection section 19 becomes dirty or deteriorates. In other words, if the output level of the smoke detector 19 when the smoke concentration is zero is zero level, this zero level was initially set at point A as shown in Figure 8;
Due to deterioration, the dirt gradually begins to rise or fall like a curve ○B or ○C, but the zero level shift circuit section 20 detects this rise or fall and always adjusts it to a curve ○B or ○C. The zero level is shifted accordingly. Also, the self-check circuit section 2
3, when the zero level shift range of the zero level shift circuit section 20 exceeds the range of x, x' shown in FIG. The detection signal is output to the function stoppage determination circuit section 22. The range of the zero level shift is determined by the smoke detection ability of the smoke detection section 19, allowable dirt, and degree of deterioration. At the same time as the function stoppage detection signal is input, the function stoppage determination circuit section 22 switches its output from "L" to "H" to notify the arithmetic signal processing circuit section 26 that the function of the smoke detector 19 has stopped. When called by the receiver 1, the arithmetic signal processing circuit unit 26 returns function stop data to notify the receiver 1 side, and the receiver 1
On the side, the display section 17 or 17' indicates that the function of the smoke detection section 19 of the smoke detector 2 has stopped. Therefore, with this display, the administrator can immediately replace the smoke detector 2, thereby preventing false alarms.

In this way, in this system, both the receiver 1 and the smoke detector 2 are made intelligent to share their functions, and the general smoke detectors 3a and 3b are also integrated.
The reliability of the system is increased by allowing the mixture of
Furthermore, by constantly calling the intelligence-type smoke detector 2 from the receiver 1, the detected smoke concentration data from the smoke detector 2 and the status of the smoke detector 2 are constantly monitored, ensuring reliable system operation. It's on.

〔Effect of the invention〕

As described above, the present invention includes a plurality of photoelectric smoke detectors that output analog signals according to the detected smoke concentration, and a level that changes the voltage level or current level of the signal line when a predetermined amount of smoke or heat is detected. By connecting a general type smoke detector that outputs a signal to the signal line derived from the receiver, and specifying the address set individually for each photoelectric smoke detector using the address data of the transmitted signal. , accessing each of the smoke detectors individually and returning the sensing output, and monitoring the voltage or current of the signal line,
This is a fire alarm system that centrally monitors the fire detection status of each detector, and includes a zero level means that corrects zero level fluctuations due to dirt on the optical system, etc., and functions when the amount of correction exceeds the detectable level. Function stoppage determination means for determining a stop state, and a stop state that notifies a receiver of a function stop state by outputting a level signal in which the voltage level or current level of a signal line is varied in the same way as a general type sensor when determining a function stop state. Since a notification means is provided in the photoelectric smoke detector, when the correction amount of the zero level means exceeds the detectable level state, the receiver is notified that the photoelectric smoke detector is in a non-functional state. This allows the receiver to recognize the disabled smoke detector and prevent it from issuing a false alarm by ignoring the output of the photoelectric detector, and also to notify the receiver of the disabled status. If measures are taken to encourage repairs on the receiver side, it is possible to prevent false alarms as much as possible and improve the reliability of the entire system. Smoke detectors, like general type detectors, output a level signal by varying the voltage level or current level of the signal line to notify the receiver of the malfunction state. There is no need to provide a special receiving circuit on the machine side, and the system configuration does not become complicated.

[Brief explanation of the drawing]

Fig. 1 is a schematic overall configuration diagram of the present invention, Fig. 2 is a signal waveform diagram used in the same as above, Fig. 3 is a circuit block diagram of the same receiver, and Fig. 4 is an equipment of the same intelligence type smoke detector as above. 5 is a circuit block diagram of the intelligence-type smoke detector same as above, FIG. 6 is a flowchart for explaining the operation of the same, FIGS. 7 a to d are diagrams for explaining the operation of the same, Figure 8,
FIG. 9 is an explanatory diagram of the operation of the zero level shift circuit section same as above, in which 1 is a receiver, 2 is an intelligence type smoke detector, 3a is a general type smoke detector, 3b is a heat sensor, and 19 is a smoke detector. 19a is a light emitting unit, 19b is a light receiving unit, 19c is an optical system unit, 20 is a zero level shift circuit unit, 22 is a function failure determination circuit unit, 23 is a self-check circuit unit, 26 is an arithmetic signal processing circuit,
27 is a coupling circuit section.

Claims (1)

[Claims] 1. Multiple photoelectric smoke detectors that output analog signals according to the detected smoke concentration, and a general type sensor that outputs a level signal by varying the voltage level or current level of the signal line when a predetermined amount of smoke or heat is detected. The photoelectric smoke detectors are connected to the signal line derived from the receiver in a mixed manner, and each of the above smoke detectors is This is a fire alarm system that centrally monitors the fire detection status of each sensor by individually accessing and returning the detection output, and monitoring the voltage or current of the signal line. a zero level means for correcting the fluctuation of the sensor; a function failure determination means for determining that the function has stopped when the correction amount exceeds a detectable level; A fire alarm system characterized in that the photoelectric smoke detector is provided with stop state notification means for outputting a level signal with a variable voltage level or current level to notify a receiver of a stopped state.