Fire alarm system

Abstract

To provide a fire alarm facility that increases an accuracy of fire determination and further ensures prevention of non-fire alarm.SOLUTION: A fire alarm facility 1 that monitors a fire in a warning area and raises the alarm comprises: a photoelectric type smoke detector 14 that detects the fire in the warning area and transmits a fire signal; an entry / exit control system 100 that detects a presence or absence of a person in the warning area and transmits a detection signal; and a fire alarm control unit 48 that outputs a caution warning without outputting a fire alarm when a low-risk fire or the presence of a person in a warning area is determined based on the fire signal from the photoelectric type smoke detector 14 and the detection signal from the entry / exit control system 100.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a fire alarm system that monitors for fires by connecting a fire detector to a receiver. [Background technology]

[0002] Conventionally, in the fire alarm system known as the R type, a fire detector with a transmission function and a unique address is connected to a receiver, and in the normal monitoring state, the detection values ​​of smoke concentration, temperature, etc. are collected and monitored by calling the fire detectors whose detector addresses are specified in sequence. In the event of a fire, a search command is issued from the receiver based on a fire interrupt signal from the fire detector to identify the address of the fire detector that triggered the alarm and collect the detection values. If the detection value exceeds a specified fire alarm threshold, it is determined to be a fire and a fire alarm is output, and further, linked control is performed for the exhaust system, fire doors, automatic reporting to firefighting authorities, etc.

[0003] In addition, conventional fire alarm systems use photoelectric smoke detectors to detect smoke caused by fires. However, conventional photoelectric smoke detectors can also give false fire alarms due to smoke from cooking or steam in the bathroom, not just smoke caused by fires.

[0004] In order to prevent false fire alarms due to causes other than fire, a so-called two-wavelength photoelectric smoke detector has been proposed (Patent Document 2), which shines light of two different wavelengths into the smoke detection space and determines the ratio of the light intensities of the different wavelengths of the light scattered by the smoke to determine the type of smoke, thereby improving the accuracy of smoke identification and ensuring the prevention of false fire alarms. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2007-265353 A [Patent Document 2] JP 2004-325211 A [Patent Document 3] Japanese Patent Application Publication No. 6-314384 Summary of the Invention [Problem to be solved by the invention]

[0006] By the way, when such a conventional two-wavelength photoelectric smoke detector is connected to a receiver to monitor for fires, the receiver can distinguish between white smoke caused by a smoldering fire and black smoke caused by a combustion fire and output a fire alarm, making it possible to respond according to the level of fire danger.

[0007] However, when steam from a bathroom or other area flows into a photoelectric smoke detector, it may give an identification result similar to the white smoke caused by a smoldering fire, and there remains the possibility that a non-fire cause such as steam may be mistaken for a white smoke fire and a non-fire alarm may be issued.

[0008] An object of the present invention is to provide a fire alarm system which improves the accuracy of fire judgment and further ensures the prevention of false fire alarms. [Means for solving the problem]

[0009] (Fire alarm system) The present invention relates to a fire alarm system that monitors and issues an alarm for a fire in a warning area, A fire detector that detects a fire in a warning area and transmits a fire signal; A human detection means for detecting the presence or absence of a human in the alert area and transmitting a detection signal; Based on the fire signal from the fire detector and the detection signal from the human detection means Controlling the alarm action A fire alarm control unit; Equipped with 、 The fire alarm control unit When it is determined that a fire is low in danger and that a person is present in a warning area based on the fire signal and the detection signal, a caution alarm is output without outputting a fire alarm; When it is determined that a fire is of low danger and that no one is present in the warning area based on the fire signal and the detection signal, a fire alarm is output; When a high-risk fire is determined based on the fire signal, a fire alarm is issued regardless of whether or not people are present in the warning area. It is characterized by:

[0010] ( Non-fire factors ) The fire alarm control unit Furthermore, Distinguish non-fire factors based on fire signals, When the presence of a person in the alert area is determined based on the detection signal after determining that a non-fire factor has occurred, output of a caution alarm indicating the occurrence of a non-fire factor is suspended; When it is determined that there is no person in the alert area based on the detection signal after determining that there is a non-fire cause, a warning alarm is outputted to indicate the occurrence of a non-fire cause. .

[0011] (Fire alarm output according to the level of fire danger) The fire alarm control unit outputs a different fire alarm in accordance with the determined degree of fire danger.

[0012] (White smoke fires and black smoke fires) A low-risk fire determined by the fire alarm control unit includes a white smoke fire, and a high-risk fire determined by the fire alarm control unit includes a black smoke fire. Effect of the Invention

[0013] (Basic effect) The present invention is a fire alarm system that monitors and issues an alarm for fires in a security zone, and is equipped with a fire sensor that detects a fire in the security zone and transmits a fire signal, a person detection means that detects the presence or absence of people in the security zone and transmits a detection signal, and a fire alarm control unit that outputs a caution alarm rather than a fire alarm when it determines that there is a low-risk fire and the presence of people in the security zone based on the fire signal from the fire sensor and the detection signal from the person detection means.Therefore, when there is a high possibility that non-fire factors such as steam from a bathroom, kitchen, etc. have been caused by occupants, the system only issues a caution alarm to alert the occupants rather than outputting a fire alarm, and by notifying the occupants of the caution alarm, it is possible to respond to the fire even if it is a fire and not a non-fire.

[0014] (Fire alarm effect) The fire alarm control unit outputs a fire alarm when it determines that a low-risk fire is present in the alert area and then determines that there are no people in the alert area, and when it determines that a high-risk fire is present, making it possible to respond to the fire immediately when there is no one in the room and there is a low possibility of non-fire factors such as steam from the bathroom or kitchen, or when the fire is a high-risk fire.

[0015] (Fire alarm output according to the level of fire danger) The fire alarm control unit outputs different fire alarms according to the determined degree of fire danger, thereby enabling necessary measures to be taken according to the state of the fire. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is an explanatory diagram showing an embodiment of a fire alarm system combined with an entrance / exit management system. [Diagram 2] An explanatory diagram showing the outline of the entrance / exit control system in Figure 1. [Diagram 3] Block diagram showing the circuit configuration of the photoelectric smoke detector installed in the fire alarm system shown in Figure 1. [Figure 4] FIG. 4 is an explanatory diagram showing an embodiment of the structure of the smoke detector in FIG. [Diagram 5] An explanatory diagram showing the smoke detection values ​​and their ratios detected by the smoke detector structure of Figure 3 for smoke when a cotton wick and kerosene are burned. [Figure 6] 2 is a flowchart showing the control operation in the receiver of FIG. 1. [Figure 7] A flow chart showing the control operation of the photoelectric smoke detector of FIG. [Figure 8] FIG. 1 is an explanatory diagram showing an embodiment of a fire alarm system combined with a human sensor. [Figure 9] FIG. 1 is an explanatory diagram showing an embodiment of a fire alarm system combined with a security system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] [Fire alarm system] (Fire alarm system overview) Fig. 1 is an explanatory diagram showing an embodiment of a fire alarm system combined with an entrance / exit management system. As shown in Fig. 1, for example, an R-type receiver 10 is installed in a monitoring center or a manager's room of a facility where a fire alarm system 1 is installed, and signal lines 12-1 to 12-3 are drawn from the receiver 10 for each system to the alert area.

[0018] A plurality of photoelectric smoke detectors 14 each having a transmission function and each having a unique address set thereto are connected to the signal line 12-1. The photoelectric smoke detectors 14 are so-called dual-wavelength type photoelectric smoke detectors having a function of detecting a first smoke detection value A1 by receiving light having a first wavelength λ1 and scattered light from smoke at a first scattering angle θ1, and detecting a second smoke detection value A2 by receiving light having a second wavelength λ2 and scattered light from smoke at a second scattering angle θ2.

[0019] Here, in the following description, the first smoke detection value A1 and the second smoke detection value A2 may simply be referred to as the smoke detection value A1 and the smoke detection value A2.

[0020] In addition to the so-called two-wavelength photoelectric smoke detector 14, ordinary photoelectric smoke detectors and heat detectors equipped with a transmission function are also connected to the signal line 12-1, and on-off type fire detectors and transmitters are connected to the detector line drawn from the repeater equipped with a transmission function, but are not shown in the figure.

[0021] The signal lines 12-2 and 12-3 are connected to control devices such as a local sound system 18, an exhaust system 20, and a fire door 22 via a repeater 16 having a transmission function and a unique address set thereto.

[0022] The local acoustic device 18, under the control of the receiver 10, outputs a specified local acoustic alarm to notify the outbreak of a fire in a warning area. In this embodiment, if the receiver 10 recognizes a white smoke fire, it outputs a local acoustic alarm including a message urging people to check the scene, and if the receiver 10 identifies a black smoke fire, it outputs a local acoustic alarm including a message urging people to evacuate.

[0023] The exhaust device 20 is activated by a control command from the receiver 10 to ventilate the restricted area. The fire door 22 is latched open by a control command from the receiver 10 and is operated to the closed position, closing off the compartment where the fire has occurred and preventing the spread of the fire.

[0024] The maximum number of addresses set for each line in terminal devices such as photoelectric smoke detectors 14 and repeaters 16 connected to signal lines 12-1 to 12-3 is, for example, 255, and a maximum of 255 terminal devices can be connected to each of signal lines 12-1 to 12-3.

[0025] (Receiver functional configuration) The receiver 10 is provided with a main CPU 26 and sub-CPU boards 28-1 to 38-3, and each of the sub-CPU boards 28-1 to 28-3 is provided with a sub-CPU 30 and a transmission unit 32. The main CPU 26 and the sub-CPU 30 are connected by a serial transfer bus 34, and transmit and receive data between them.

[0026] Connected to the main CPU 26 are a display 36 with a touch panel using an LCD panel or the like; a display unit 38 provided with representative lights for fire, gas leaks, and faults, LED indicator lights, etc.; an operation unit 40 provided with various switches necessary for fire monitoring, such as a fire determination switch, a district audio stop switch, and a report transfer stop switch; an audio alarm unit 42 provided with a speaker; and a report transfer unit 44.

[0027] Although not shown, emergency broadcast devices and automatic reporting devices are connected to the reporting unit 44 as reporting destinations. The emergency broadcast device operates in response to a reporting signal from the receiver 10, and outputs an emergency broadcast from speakers installed in the alert area to notify of the occurrence of a fire and to guide evacuation. When the emergency broadcast device is activated, the local sound alarm from the local sound device 18 is stopped. The automatic reporting device operates in response to a reporting signal from the receiver 10, and makes a 119 call connection via a public telephone line to report the occurrence of a fire to a firefighting agency.

[0028] Furthermore, a communication adapter 45 is connected to the main CPU 26 , and the communication adapter 45 transmits and receives signals to and from the entrance / exit management system 100 .

[0029] (Entrance / Exit Management System) Fig. 2 is an explanatory diagram showing an outline of an entrance / exit management system. As shown in Fig. 2, an entrance / exit management system 100 installed in a facility such as an office building or a factory is composed of a center device 102, a client 104, a local control panel 108, a card reader 110 for entering and exiting the room, and an electronic lock 112.

[0030] The center device 102 is installed in a monitoring center, a manager's room, etc., and the client 104 is installed in a general affairs department that handles entrance and exit management. The local control boards 108 are installed, for example, on each floor of a facility. The local control boards 108 are connected to the center device 102 and the client 104 via a LAN line 106.

[0031] The card reader 110 is placed on the outside of the door that serves as the entrance and exit of each room, and the door is equipped with an electric lock 112. The card reader 110 and the electric lock 112 are connected to a signal line from a local control panel 108 installed on the same floor.

[0032] The card reader 110 reads the specified user identification information recorded on a magnetic card or contactless IC card carried by the user and compares it with pre-registered user identification information. If the comparison results in a match and authentication is successful, the card reader 110 sends an authentication signal to the local control panel 108.

[0033] When the local control panel 108 receives an authentication signal from the card reader 110, it transmits the authentication signal to the center device 102 via the LAN line 106, and causes the arrival time or departure time to be recorded in the entrance / exit information managed by the center device 102. In addition, when the local control panel 108 receives an authentication signal from the card reader 110, it outputs a control signal to an electric lock 112 installed at the corresponding entrance / exit to control unlocking and enable entry and exit.

[0034] The center device 102 has a function of displaying management information such as a map of the facility in which the entrance / exit management system 100 is installed, as well as a function as a database for storing and managing entrance / exit information showing the status of occupants.

[0035] The client 104 is connected to the center device 102 and a local control panel 108 via a LAN line 106, and performs various settings and processes such as registration, deletion, and history search of user identification information corresponding to magnetic cards and contactless IC cards between the client 104 and a card reader 110 via the local control panel 108.

[0036] In addition, in this embodiment, a communication adapter 114 is connected to the center device 102, and the communication adapter 114 is connected to a communication adapter 45 provided in the receiver 10 of the fire alarm system 1 shown in Figure 1, and can transmit an entry / exit control signal indicating the status of people present in the room upon request from the receiver 10.

[0037] [Receiver control functions] As shown in FIG. 1, the main CPU 26 of the receiver 10 is provided with a fire alarm control unit 48 as a function realized by executing a program.

[0038] Further, a transmission control unit 46 is provided as a function realized by executing a program in the sub-CPU 30 provided on the sub-CPU boards 28-1 to 28-3 of the receiver 10. The transmission control unit 46 provided in the sub-CPU 30 on the sub-CPU board 28-1 controls the collection of the first smoke detection value A1 and the second smoke detection value A2 detected by the two-wavelength photoelectric smoke detector 14 connected to the signal line 12-1.

[0039] In addition, the transmission control unit 46 of the sub-CPU boards 28-2, 38-3 performs fire interlocking control by transmitting a control signal specifying the address of the repeater 16 that connects control devices such as the local sound device 18, exhaust device 20, and fire door 22 connected to the respective signal lines 12-2, 12-3.

[0040] (Control of collection of detector detection data) The transmission control unit 46 provided in the sub-CPU 30 of the sub-CPU board 28-1 controls the collection of detection data by instructing the transmission unit 32 to send and receive signals between the photoelectric smoke detector 14 connected to the signal line 12-1 in accordance with a predetermined communication protocol.

[0041] The downstream signal from the transmission unit 32 to the photoelectric smoke detector 14 is transmitted in voltage mode. This voltage mode signal is transmitted as a voltage pulse that changes the line voltage of the signal line 12-1 between, for example, 18 volts and 30 volts.

[0042] On the other hand, the upstream signal from the photoelectric smoke detector 14 to the transmission unit 32 is transmitted in current mode. In this current mode, a signal current is passed through the signal line 12-1 at the timing of bit 1 of the transmission data, and the upstream signal is transmitted to the receiver 10 as a so-called current pulse train.

[0043] During normal monitoring, the data collection control by the transmission control unit 46 of the sub-CPU 30 instructs the transmission unit 32 to transmit a broadcast batch AD conversion signal including a batch AD conversion command at regular intervals, and the photoelectric smoke detector 14 receiving this batch AD conversion signal converts the smoke detection value detection signals of the first smoke detection value A1 and the second smoke detection value A2 output from the smoke detection unit by AD conversion into digital smoke detection value signals and holds them.

[0044] Next, the transmission control unit 46 of the sub-CPU 30 transmits a call signal including a polling command sequentially specifying the terminal addresses. When the photoelectric smoke detector 14 receives a call signal having an address that matches its own address, it transmits a call response signal including the first smoke detection value A1 and the second smoke detection value A2 that it is holding at that time to the receiver 10.

[0045] In addition, if the photoelectric smoke detector 14 is equivalent to a type 2 sensitivity smoke detector that alerts a fire at a smoke density of, for example, 10% / m, a smoke density threshold equivalent to type 1 sensitivity, for example a smoke density threshold of 5.0% / m, is set as a warning indication threshold AP1th for the first smoke detection value A1 in the photoelectric smoke detector 14, and when the detected first smoke detection value A1 becomes equal to or exceeds the warning indication threshold AP1th, it is determined that a fire has been alerted, and a fire interrupt signal is sent to the receiver 10.

[0046] Note that a smoke concentration threshold equivalent to a single sensitivity level, for example, a smoke concentration threshold of 5.0% / m, is set as the attention display threshold value AP2th for the second smoke detection value A2 in the photoelectric smoke detector 14. When the detected second smoke detection value A2 becomes equal to or higher than the attention display threshold value AP2th of the smoke detection value data, it is determined that a fire has occurred, and a fire interrupt signal may be transmitted to the receiver 10.

[0047] When the transmission control unit 46 of the sub-CPU 30 receives a fire interrupt signal from the photoelectric smoke detector 14 via the transmission unit 32, it transmits a group search command signal to identify the group including the photoelectric smoke detector 14 that has issued a fire alarm. Subsequently, it transmits an in-group search command signal to identify the address of the photoelectric smoke detector 14 that has issued a fire alarm, intensively collects the first and second smoke detection values A1 and A2, and transmits them to the main CPU 26 via the serial transfer bus 34.

[0048] The intensive collection of the first and second smoke detection values A1 and A2 by the transmission control unit 46 of the sub-CPU 30 shortens the transmission cycle of the batch AD conversion signal, and by transmitting a call signal specifying the address of the photoelectric smoke detector 14 that has issued a fire alarm after transmitting the batch AD conversion signal, the first smoke detection value A1 and the second smoke detection value A1 of the photoelectric smoke detector 14 are continuously collected.

[0049] (Fire alarm control) The fire alarm control unit 48 of the main CPU 26 calculates the ratio R = A1 / A2 from the first smoke detection value A1 and the second smoke detection value A2 received from the sub-CPU 30, and compares it with a predetermined ratio threshold value Rth. When R ≥ Rth, a white smoke fire is discriminated, and when R < Rth, a black smoke fire is discriminated. The details of the discrimination between the white smoke fire and the black smoke fire by the fire alarm control unit 48 will be clarified in the subsequent description of the photoelectric smoke detector 14.

[0050] Subsequently, the fire alarm control unit 48 of the main CPU 26 instructs the communication adapter 45 to establish a communication connection with the center device 102 of the entry / exit management system 100 shown in FIG. 2 via the communication adapter 114. At that time, it receives the entry / exit management information indicating the status of the occupants managed by the center device 102 and discriminates the presence or absence of the occupants.

[0051] Next, if the fire alarm control unit 48 of the main CPU 26 has identified, for example, a white smoke fire, when the first smoke detection value A1 is, for example, equal to or greater than the fire alarm threshold A1th = 10% / m corresponding to the two-level sensitivity setting of the photoelectric smoke detector 14, it performs fire alarm control according to the presence or absence of people in the room.

[0052] When the fire alarm control unit 48 identifies a white smoke fire and also identifies the presence of people in the room, it determines that there is some non-fire cause and performs control to output a caution alarm rather than a fire alarm.

[0053] In addition, when the fire alarm control unit 48 identifies a white smoke fire and determines that no one is present in the room, it determines that the fire is a white smoke fire in which white smoke is slowly increasing due to a smoldering fire, and performs control to output a fire alarm indicating a white smoke fire.

[0054] A fire alarm indicating a white smoke fire by the fire alarm control unit 48 turns on the fire representative light on the display unit 38, outputs a specified main audio alarm indicating a fire from the speaker of the audio alarm unit 42, and displays fire alarm information on the display 36 including the location of the fire and type information indicating a white smoke fire based on the sensor address where the fire was detected, and further performs specified white smoke fire linkage control.

[0055] The white smoke fire interlocking control by the fire alarm control unit 48 transmits a local acoustic control signal specifying the address of the local acoustic device 18 in the alert area corresponding to the address of the photoelectric smoke detector 14 that triggered the fire (i.e. the address of the repeater 16 to which the local acoustic device 18 is connected), and activates the local acoustic device 18 specified by the address, which outputs a local acoustic alarm including an audio message urging residents and others to check the scene, since a white smoke fire is a fire that produces white smoke due to a smoldering fire in the early stages of a fire.

[0056] In addition, the white smoke fire linkage control by the fire alarm control unit 48 specifies the address of the exhaust device 20 installed in the alert area corresponding to the address of the photoelectric smoke detector 14 that triggered the fire (i.e., the address of the repeater 16 to which the exhaust device 20 is connected) and sends a control signal, and the exhaust device 20 is activated to exhaust the white smoke generated by the smoldering fire to the outside, thereby providing ventilation.

[0057] On the other hand, if the fire alarm control unit 48 of the main CPU 26 has identified, for example, a black smoke fire, it will determine that the rapidly expanding burning fire is generating black smoke and posing a high risk of danger, and will perform control to output a fire alarm indicating a black smoke fire, regardless of whether anyone is present in the room.

[0058] A fire alarm indicating a black smoke fire by the fire alarm control unit 48 turns on the fire representative light on the display unit 38, outputs a predetermined main audio alarm indicating a fire from the speaker of the audio alarm unit 42, displays fire alarm information on the display 36 including the location of the fire and information on the type of fire indicating a black smoke fire based on the address of the sensor where the fire was detected, and further performs predetermined black smoke fire linkage control.

[0059] The black smoke fire interlocking control by the fire alarm control unit 48 activates the local sound device 18, the exhaust device 20, and the fire doors 22 by transmitting a control signal specifying the address of the repeater 16 connected to each of the local sound device 18, the exhaust device 20, and the fire doors 22 that are installed in the alert area corresponding to the address of the photoelectric smoke detector 14 that has activated the fire.

[0060] The local sounding device 18 activates based on the identification of a black smoke fire to issue a local sounding alarm including a voice message encouraging residents to evacuate, since black smoke fires generate black smoke due to combustion and spread quickly, which is highly dangerous. In addition, the exhaust device 20 is activated based on the identification of a black smoke fire to ventilate the compartment where the fire started, and the closing activation of the fire door 22 closes the compartment where the fire started to suppress the spread of the fire.

[0061] Furthermore, as black smoke fire interlocking control by the fire alarm control unit 48, it instructs the notification transfer unit 44 to output a notification transfer signal to an emergency broadcast device or automatic reporting device (not shown) to perform interlocking control. The emergency broadcast device is activated by a notification transfer signal from the receiver 10, and issues an emergency broadcast from a speaker installed in the alert area notifying the occurrence of a fire and including a voice message encouraging evacuation. At this time, the fire alarm control unit 48 sends a stop signal to the local sound device 18 to stop outputting the local sound alarm, ensuring that the emergency broadcast can be heard.

[0062] The automatic reporting device is activated by a signal from the receiver 10, and automatically reports the occurrence of a fire to a firefighting agency by calling 119 over the public telephone line, requesting that the fire be extinguished.

[0063] [Photoelectric smoke detector] (Circuit configuration) Fig. 3 is a block diagram showing the circuit configuration of a photoelectric smoke detector provided in the fire alarm system of Fig. 1. As shown in Fig. 3, the photoelectric smoke detector 14 of this embodiment is composed of a detector control unit 50 composed of a computer circuit equipped with a CPU, memory, and various input / output ports, a transmission unit 52 that transmits and receives signals to and from the receiver 10 via a signal line 12 connected to an S terminal and an SC terminal, a power supply unit 54 that converts the power supply voltage supplied via the signal line 12 into a predetermined stabilized voltage and outputs it, a light emission drive unit 56, a smoke detection unit 60, and amplifier circuit units 68, 70.

[0064] The smoke detector 60 is provided with a light emitting element 62 that simultaneously emits light including a first wavelength λ1 and a second wavelength λ2. The light of the first wavelength λ1 emitted from the light emitting element 62 has a central wavelength set to 600 nm or more, and the light of the second wavelength λ2 has a central wavelength set to 500 nm or less, and in this embodiment, the first wavelength λ1 is set to, for example, 700 nm, and the second wavelength λ2 is set to, for example, 450 nm.

[0065] In this embodiment, a white LED (white light emitting diode) is used as the light emitting element 62. The white LED is, for example, a combination of a blue LED and a phosphor, and the light of the blue LED passes through the phosphor to emit white light, and this emitted light color includes light with a first wavelength λ1 = 700 nm and light with a second wavelength λ2 = 450 nm, and the light of the first wavelength λ1 and the light of the second wavelength λ2 can be irradiated simultaneously inside the smoke detection unit 60.

[0066] In addition, a two-color LED (two-color light-emitting diode) can also be used as the light-emitting element 62 of this embodiment. The two-color LED includes a first light-emitting chip that emits light with a first wavelength λ1=700 nm and a second light-emitting chip that emits light with a second wavelength λ2=450 nm, and by driving both of them simultaneously, the smoke detection unit 60 can be irradiated with light of the first wavelength λ1 and the second wavelength λ2 simultaneously.

[0067] The first light receiving element 64 uses a photodiode (PD) sensitive to the first wavelength λ1, and the second light receiving element 66 uses a photodiode (PD) sensitive to the second wavelength λ2.

[0068] In addition, the first light receiving element 64 and the second light receiving element 66 may be a wideband photodiode sensitive to the visible light wavelength band, with a filter layer that receives only the wavelength bands of the first wavelength λ1 and the second wavelength λ2 provided in a PD molding (transparent cover member), or a filter that transmits the wavelength bands of the first wavelength λ1 and the second wavelength λ2 may be disposed in front of the wideband photodiode.

[0069] The amplifier circuit section 68 amplifies the received light signal of the smoke scattered light of the first wavelength λ1 received by the first light receiving element 64, and outputs the received light signal which becomes the first smoke detection value A1 to the sensor control section 50. In addition, the amplifier circuit section 70 amplifies the received light signal of the smoke scattered light received by the second light receiving element 66, and outputs the received light signal which becomes the second smoke detection value A2 to the sensor control section 50.

[0070] (Smoke Detection Division) Fig. 4 is an explanatory diagram showing an embodiment of the structure of the smoke detection unit in Fig. 3. As shown in Fig. 4, a light emitting element 62, a first light receiving element 64 and a second light receiving element 66 are arranged in a smoke detection unit 60 into which smoke from the outside flows.

[0071] For example, a light-emitting element 62 using a white LED irradiates light including a first wavelength λ1 and a second wavelength λ2 in the direction of an optical axis 62a, and as described above, the light of the first wavelength λ1 is set to 700 nm, and the light of the second wavelength λ2 is set to 450 nm.

[0072] The first scattering angle θ1 formed by the intersection of the optical axis 62a of the light-emitting element 62 and the optical axis 64a of the first light-receiving element 64 is set in the range of 20° to 70°, and the optical axis 62a of the light-emitting element 62 and the optical axis 64a of the first light-receiving element 64 are arranged to intersect at a predetermined angle in the range of 110° to 160°.

[0073] In addition, the second scattering angle θ2 formed by the intersection of the optical axis 62a of the light-emitting element 62 and the optical axis 66a of the second light-receiving element 66 is set to the range of 110° to 150°, and the light-emitting element 62 and the optical axis 66a of the second light-receiving element 66 are arranged so that they intersect at a predetermined angle in the range of 30° to 70°.

[0074] In this embodiment, the first scattering angle θ1 is set to 30°, and therefore the optical axis 62a of the light-emitting element 62 and the optical axis 64a of the first light-receiving element 64 are arranged to intersect at a crossing angle of, for example, 150°, and the second scattering angle θ2 is set to 120°, and therefore the optical axis 62a of the light-emitting element 62 and the optical axis 66a of the second light-receiving element 66 are arranged to intersect at a crossing angle of, for example, 60°.

[0075] Since the first photodetector 64 is sensitive to light of the first wavelength λ1 = 700 nm emitted from the light-emitting element 62, when the light-emitting element 62 emits light of the first wavelength λ1, the scattered light at a scattering angle θ1 = 30° by the smoke flowing into the smoke detection unit 60 is received by the first photodetector 64, and a first smoke detection value A1 is obtained.

[0076] In addition, since the second light receiving element 66 is sensitive to light of the second wavelength λ2 = 450 nm emitted from the light emitting element 62, when the light emitting element 62 emits light of the second wavelength λ2 simultaneously with light of the first wavelength λ1, the scattered light at the second scattering angle θ2 = 120° by the smoke flowing into the smoke detection unit 60 is received by the second light receiving element 66, and a second smoke detection value A2 is obtained at the same time.

[0077] When the sensor control unit 50 shown in FIG. 3 receives a batch AD converted signal from the receiver 10 via the transmission unit 52, it instructs the light emitting drive unit 56 to drive the light emitting element 62 to emit white light including a first wavelength λ1 and a second wavelength λ2, and the forward scattered light having a first scattering angle θ1=30° due to the first wavelength λ1 is received by the first light receiving element 64. In response to this, the first smoke detection value A1 output from the amplifier circuit unit 68 is AD converted to digital data, read in, and stored in memory.

[0078] At the same time, since the backscattered light with the second wavelength λ2 and the second scattering angle θ2 = 120° is received by the second light receiving element 66, the sensor control unit 50 AD converts the second smoke detection value A2 output from the amplifier circuit unit 70 in response to the light received by the second light receiving element 66 into digital data, reads it in, and stores it in memory.

[0079] Next, the detector control unit 50 compares the first smoke detection value A1 stored in memory with a warning indication threshold AP1th that is predetermined in accordance with the set sensitivity of the photoelectric smoke detector 14, and determines that a fire has been alerted if the first smoke detection value A1 is equal to or greater than the warning indication threshold AP1th, and controls the transmission unit 52 to transmit a fire interrupt signal to the receiver 10.

[0080] Here, as described above, when the photoelectric smoke detector 14 is equivalent to a type 2 sensitivity with a fire alarm threshold A1th of 10% / m, the warning display threshold AP1th is set to, for example, AP1th=5% / m, which is equivalent to a type 1 sensitivity. Also, when the photoelectric smoke detector 14 is equivalent to a type 3 sensitivity with a fire alarm threshold A1th of 15% / m, the warning display threshold AP1th is set to, for example, APth=10% / m, which is equivalent to a type 2 sensitivity.

[0081] (Distinguishing between white and black smoke fires) FIG. 5 is an explanatory diagram showing smoke detection values ​​and their ratios detected by the smoke detector structure of FIG. 4 for smoke when a cotton wick and kerosene are burned.

[0082] As shown in Figure 5, the first smoke detection value A1 is the received output of scattered light with a first wavelength λ1 = 700 nm and a first scattering angle θ1 = 30°, and the second smoke detection value A2 is the received output of scattered light with a second wavelength λ2 = 450 nm and a second scattering angle θ2 = 120°.

[0083] If the ratio R=A1 / A2 of the first and second smoke detection values ​​A1, A2 measured when burning such a cotton wick and kerosene is taken, then in the case of cotton wick, R=8.0 and in the case of kerosene, R=2.3, which shows a significant difference in the ratio R between the cotton wick and kerosene, making it possible to identify the type of smoke based on the ratio R.

[0084] For this reason, a ratio threshold value Rth for identifying the type of smoke can be set to, for example, Rth = 5, and if R ≥ 5, it can be determined to be a white smoke fire where white smoke is generated by smoldering, and if R < 5, it can be determined to be a black smoke fire where black smoke is generated by combustion.

[0085] In this embodiment, the receiver 10 shown in FIG. 1 collects the first and second smoke detection values ​​A1, A2 detected by the photoelectric smoke detector 14 that has activated a fire alarm, and the fire alarm control unit 48 calculates the ratio R=A1 / A2 of the first and second smoke detection values ​​A1, A2, and if R≧5, determines that the fire is a white smoke fire where white smoke is generated by smoldering, and if R<5, determines that the fire is a black smoke fire where black smoke is generated by combustion.

[0086] In addition, when the fire alarm control unit 48 of the receiver 10 determines that there is a white smoke fire based on the first and second smoke detection values ​​A1, A2, it determines that there is a confirmed fire if the first smoke detection value A1 is equal to or higher than the fire alarm threshold A1th corresponding to a smoke concentration of 10% / m for type 2 sensitivity, and performs control to output a fire alarm including information indicating a white smoke fire.

[0087] Similarly, when the fire alarm control unit 48 of the receiver 10 determines that there is a black smoke fire based on the first and second smoke detection values ​​A1, A2, it determines that there is a confirmed fire if the second smoke detection value A2 is equal to or greater than the fire alarm threshold A2th corresponding to a smoke concentration of 10% / m for type 2 sensitivity, and performs control to output a fire alarm including information indicating a black smoke fire.

[0088] (Non-fire cause identification) When a non-fire cause, such as steam from a bathroom, flows into the smoke detection unit 60 of the photoelectric smoke detector 14 shown in FIG. 4, the ratio R of the first and second smoke detection values ​​A1, A2 will be a large value, such as exceeding R=10.

[0089] For this reason, a non-fire cause threshold value RSth for identifying steam is set to, for example, RSth=12, and if R≧12, it is identified as a non-fire cause such as steam.

[0090] The fire alarm control unit 48 of the receiver 10 also judges whether a non-fire cause has occurred based on the ratio R of the first and second smoke detection values ​​A1, A2, and if R≧12, it judges that a non-fire cause has occurred, such as steam, and performs alarm control based on the entry / exit detection signal obtained from the entry / exit management system 100.

[0091] That is, the fire alarm control unit 48 discerns non-fire factors based on the ratio R of the smoke detection values ​​A1, A2, and when it determines the presence of people in the room based on the entry / exit detection signal, it refrains from outputting a warning alarm indicating a non-fire factor, whereas when it determines that there is a non-fire factor and no people in the room, it performs control to output a warning alarm indicating a non-fire factor.

[0092] For this reason, if there is someone in the room when a non-fire alarm is determined to be due to steam or cooking smoke from the bathroom, etc., it is determined that the steam or cooking smoke is due to the person using the bathroom, so a warning alarm is deemed unnecessary and withheld. On the other hand, if there is no one in the room when a non-fire cause is determined, it means that steam or cooking smoke from the bathroom, etc. has been left unattended, so a warning alarm is issued and the necessary response can be made.

[0093] Furthermore, in this embodiment, a sensor is provided as a human detection means for detecting the operation of switches on appliances such as home appliances, water heaters, and lighting in the security area, and when this sensor detects the operation of a switch on an appliance, it transmits a presence detection signal to the receiver indicating whether or not a person is present.

[0094] For this reason, the fire alarm control unit 48 uses a human presence sensor to detect the operation of the switches for the water heater and lights in the bathroom, the switches for cooking appliances such as a gas range, and the switches for home appliances such as the television and air conditioner, and since it is believed that when these are operating, people are present in the room and there is a possibility of a non-fire cause being generated, the fire alarm control unit 48 determines whether a non-fire cause is present based on the ratio R of the smoke detection values ​​A1, A2, and holds off on outputting a warning alarm indicating a non-fire cause in the receiver, and in parallel controls the display device (not shown) in the room to output a warning alarm indicating a non-fire cause.

[0095] [Fire monitoring and control of fire alarm systems] Fig. 6 is a flow chart showing the control operation in the receiver of Fig. 1, which is the control operation by the transmission control section 46 and the fire alarm control section 48 shown in Fig. 1. Also, Fig. 7 is a flow chart showing the control operation in a photoelectric smoke detector, which is the control operation by the detector control section 50. Furthermore, the control in Fig. 6 and Fig. 7 is characterized in that the receiver 10 side distinguishes between a white smoke fire, a black smoke fire, and a non-fire cause.

[0096] (Receiver control) As shown in Figure 6, in step S1, the transmission control unit 46 of the receiver 10 transmits a broadcast batch AD conversion signal designating all photoelectric smoke detectors 14 to the signal line 12-1 at a predetermined period, AD converts the smoke detection values ​​A1, A2, which are analog signals detected on the photoelectric smoke detector 14 side, into digital signals and stores them, then transmits a call signal designating the addresses of the photoelectric smoke detectors 14 in sequence, receives a call response signal transmitted by the photoelectric smoke detector 14 that received the call signal, and performs call response control to monitor the status of the photoelectric smoke detectors 14 to see if they are operating normally.

[0097] Next, when the transmission control unit 46 determines in step S2 that it has received a fire interrupt signal from the photoelectric smoke detector 14 that has alerted a fire, it proceeds to step S3 and searches for the address of the photoelectric smoke detector 14 that has alerted a fire and sent the fire interrupt signal by transmitting a group search command signal and an intra-group search command signal.

[0098] Next, the transmission control unit 46 proceeds to step S4, shortens the period of the batch AD conversion signal and transmits a call signal specifying the address of the photoelectric smoke detector 14 that transmitted the fire interrupt signal, thereby repeatedly acquiring the first and second smoke detection values ​​A1, A2 from the photoelectric smoke detector 14 that has issued a fire alert, and transmits them to the fire alarm control unit 48 of the main CPU 26.

[0099] In step S5, the fire alarm control unit 48 calculates the ratio R=A1 / A2 of the first and second smoke detection values ​​A1, A2, and in step S6 compares this with a ratio threshold value Rth=5 preset based on Fig. 5. If R≧5, the process proceeds to step S7 and determines that the fire is a white smoke fire, and if R<5, the process proceeds to step S12 and determines that the fire is a black smoke fire. Note that if the ratio R is equal to or greater than the non-fire cause threshold value RSth=12, the fire alarm control unit 48 determines that the fire is a non-fire cause caused by steam, although this is not shown in the figure.

[0100] Next, if the fire alarm control unit 48 determines in step S6 that the ratio R is equal to or greater than the ratio threshold value Rth = 5, it proceeds to step S8, obtains occupancy information from the entry / exit management system 100, and if it determines in step S9 that there is someone present, it determines that there is some non-fire factor due to the presence of a person, and outputs a caution alarm rather than a fire alarm, and repeats the monitoring process from step S1.

[0101] On the other hand, if the fire control unit 48 determines in step S9 that no one is present, it proceeds to step S10. If it determines that the first smoke detection value A1 is equal to or greater than the fire alarm threshold A1th, it determines that a fire has been confirmed and proceeds to step S11. Since a white smoke fire has been identified and it has been determined that no one is present in the room, it outputs a fire alarm indicating a white smoke fire and performs linked control corresponding to a white smoke fire.

[0102] On the other hand, if the fire alarm control unit 48 determines in step S6 that the ratio R is less than the ratio threshold Rth = 5, it proceeds to step S12 and determines that it is a black smoke fire, and then proceeds to step S13. If it determines that the second smoke detection value A2 is equal to or greater than the fire alarm threshold A2th, it determines that a fire has been confirmed and proceeds to step S14, whereupon a fire alarm indicating a black smoke fire is output regardless of whether or not there is occupant in the room, and also performs linked control corresponding to a black smoke fire.

[0103] Next, the fire alarm control unit 48 repeats the processing from step S1 until it determines in step S15 that the fire has been restored.If it determines that the fire has been restored, it sends a fire restoration signal to the photoelectric smoke detector 14 in step S16 to restore the detector, then returns to step S1 and repeats the control from step S1.

[0104] (Photoelectric smoke detector control) As shown in Figure 7, when the detector control unit 50 of the photoelectric smoke detector 14 shown in Figure 2 determines in step S21 that it has received a batch AD conversion signal from the receiver 10, it proceeds to step S22, and detects a smoke detection value A1 detected by receiving light of the first wavelength λ1 and scattered light at the first scattering angle θ1, and a smoke detection value A2 detected by receiving light of the second wavelength λ2 and scattered light at the second scattering angle θ2 by driving the light-emitting element 62 to emit light, and stores these in memory in step S23.

[0105] Next, when the detector control unit 50 determines in step S24 that a call signal designating its own address has been received, the process proceeds to step S25 where it transmits a call response signal indicating the detector status, thereby notifying the receiver 10 of its own status.

[0106] Next, the detector control unit 50 proceeds to step S26, and if it determines that the first smoke detection value A1 is equal to or greater than the warning indication threshold AP1th = 5% / m corresponding to the second sensitivity type, a fire is alerted, and proceeds to step S27 to send a fire interrupt signal to the receiver 10. Next, if it determines in step S28 that a group search command and an intra-group search command sent from the receiver 10 have been received, the detector control unit 50 proceeds to step S29 to send a search response signal indicating a fire alert, thereby causing the receiver 10 to obtain the address of the photoelectric smoke detector 14 that alerted the fire.

[0107] Next, since the receiver 10 transmits a batch AD conversion signal followed by a call signal specifying the fire alert address at short intervals, the detector control unit 50 determines in step S30 that it has received the batch AD conversion signal and the call signal, proceeds to step S31, whereby the light-emitting element 62 is driven to emit light, thereby detecting the first and second smoke detection values ​​A1, A2 and storing them in memory, and in step S32 transmits a call response signal including the smoke detection values ​​A1, A2 to the receiver 10, which determines the ratio R of the smoke detection values ​​A1, A2, identifies whether the fire is a white smoke fire or a black smoke fire, and performs fire alarm control based on the presence or absence of people in the room.

[0108] Next, the detector control unit 50 repeats the process from step S30 until it determines in step S33 that a fire recovery signal has been received from the receiver 10, and when it determines that a fire recovery signal has been received, it returns to step S1 and repeats the same control operation.

[0109] In the control of Figures 6 and 7, the receiver 10 distinguishes between white smoke fires and black smoke fires, but the photoelectric smoke detector 14 may distinguish between white smoke fires and black smoke fires and send a fire signal including identification information for either white smoke fires or black smoke fires to the receiver 10, and the entrance / exit management system 100 may perform fire judgment and fire alarm control in combination with the presence or absence of people in the room.

[0110] [Fire alarm system combined with motion sensor] Fig. 8 is an explanatory diagram showing an embodiment of a fire alarm system combined with a human presence sensor. As shown in Fig. 8, in this embodiment, a human presence sensor 80 functioning as a human detection means is connected to a signal line 12-1 drawn from a receiver 10 via a repeater 16. The human presence sensor 80 receives infrared energy emitted from a human body by a pyroelectric element or the like, and outputs a human detection signal indicating the presence or absence of a person.

[0111] When the repeater 16 to which the human presence sensor 80 is connected receives a batch AD conversion signal transmitted from the receiver 10, it samples the human detection signal output by the human presence sensor 80 and retains the human detection information. When the repeater 16 then receives a call signal transmitted from the receiver 10 specifying the address of the repeater 16 to which the human presence sensor 80 is connected, it transmits a call response signal including the human detection information it is retaining at that time to the receiver 10.

[0112] The human presence sensor 80 is installed in an alert area such as a room in which the photoelectric smoke detector 14 is installed, and the human presence sensor 80 is installed together with the photoelectric smoke detector 14 in alert areas such as kitchens, smoking rooms, bathrooms, etc. where the occurrence of non-fire factors is expected.

[0113] The fire alarm control unit 48 provided in the main CPU 26 of the receiver 10 performs fire judgment and alarm control specific to this embodiment by combining the human detection information from the human presence sensor 80 and the results of distinguishing between white smoke fires and black smoke fires based on the photoelectric smoke detector 14.

[0114] In other words, the fire alarm control unit 48 determines that a white smoke fire has occurred when the ratio R of the smoke detection values ​​A1, A2 detected by the photoelectric smoke detector 14 becomes equal to or greater than the ratio threshold value Rth = 5, and when it determines that there is a person detected by the human presence sensor 80, it determines that there is some non-fire factor, and therefore performs control to output a caution alarm without outputting a fire alarm.

[0115] In addition, the fire alarm control unit 48 identifies a white smoke fire based on the ratio R of the smoke detection values ​​A1, A2, and when the human presence sensor 80 detects the absence of people, it determines that it is a white smoke fire in which white smoke is slowly increasing due to smoldering, and performs control to output a fire alarm indicating a white smoke fire.

[0116] On the other hand, when the fire alarm control unit 48 of the main CPU 26 determines that a black smoke fire has occurred because the ratio R of the smoke detection values ​​A1, A2 falls below the ratio threshold value Rth = 5, it determines that black smoke has been generated by a rapidly expanding burning fire and that the danger level is high, and therefore performs control to output a fire alarm indicating a black smoke fire regardless of the presence of people.

[0117] In this embodiment, the human sensor 80 is installed together with the photoelectric smoke detector 14 in places where non-fire factors are likely to occur, such as smoking rooms and kitchens. For example, if white smoke is detected in a smoking room and the presence of a person is identified, it is cigarette smoke, so no fire alarm is issued and a caution alarm is output and fire monitoring continues. Also, if white smoke is detected and no person is present, it is determined that a cigarette is still smoking and a fire alarm indicating a white smoke fire is output. Furthermore, if a black smoke fire is detected, since danger is imminent due to a combustion fire, a fire alarm indicating a black smoke fire is output regardless of the presence of people, allowing for rapid evacuation.

[0118] Furthermore, when the fire alarm control unit 48 determines that a non-fire factor has occurred because the ratio R of the smoke detection values ​​A1, A2 is equal to or greater than the non-fire factor threshold RSth=12, and determines that a person is present by the human presence sensor 80, it reserves the right to refrain from outputting a warning alarm indicating a non-fire factor. If the non-fire factor is not eliminated even after a predetermined time has elapsed, the fire control unit 48 may cancel the reserve of the warning alarm output and output a warning alarm indicating a non-fire factor.

[0119] On the other hand, the fire alarm control unit 48 determines whether a non-fire factor exists based on the ratio R of the smoke detection values ​​A1 and A2, and when the human presence sensor 80 determines that no human is present, performs control to output a warning alarm indicating a non-fire factor.

[0120] In this way, if people are present when non-fire factors are identified, a warning alarm is deemed unnecessary and is withheld; on the other hand, if no people are present when non-fire factors are determined, a warning alarm is issued, as this indicates that non-fire factors such as steam from the bathroom or cooking smoke have been left unattended, allowing the necessary response to be taken.

[0121] Other configurations and functions of the fire alarm system 1 are the same as those in the embodiment of FIG. 1, so the same reference numerals are used and the description thereof is omitted.

[0122] [Fire alarm system combined with security system] Fig. 9 is an explanatory diagram showing an embodiment of a fire alarm system combined with a security system. As shown in Fig. 9, the fire alarm system 1 of this embodiment is basically the same as the embodiment of Fig. 1, and is characterized by the incorporation of a security system 200 that functions as a human detection means.

[0123] In the security system 200, a security sensor 206 is connected to a signal line 204 drawn from a security receiving panel 202. The security sensor 206 detects the intrusion of a suspicious person into a security zone and transmits a security detection signal indicating the presence or absence of an intruder to the security receiving panel 202 via the signal line 204, causing a theft alarm to be output. As the security sensor 206, a sensor that detects infrared energy emitted by an intruder or a sensor that detects the opening of a window may be used.

[0124] The security receiving panel 202 is connected to a communication adapter 45 provided in the receiver 10 of the fire alarm system 1 via a communication adapter 208, and a fire alarm control unit 48 provided in the main CPU 26 of the receiver 10 is communicatively connected to the security system 200 via the communication adapters 45, 208, thereby obtaining security surveillance information indicating the presence or absence of an intruder detected by the security sensor 206.

[0125] The fire alarm control unit 48 provided in the main CPU 26 of the receiver 10 performs fire judgment and alarm control specific to this embodiment by combining crime prevention monitoring information indicating the presence or absence of an intruder obtained by the security system 200 with the results of discrimination between white smoke fires and black smoke fires based on the photoelectric smoke detector 14.

[0126] In other words, the fire alarm control unit 48 determines that a white smoke fire is occurring when the ratio R of the smoke detection values ​​A1, A2 detected by the photoelectric smoke detector 14 becomes equal to or exceeds the ratio threshold value Rth = 5, and when it determines that there is a presence of an intruder detected by the security system 200, it determines that there is a high possibility that the white smoke has been caused by arson by the intruder, and therefore performs control to output a fire alarm indicating a white smoke fire.

[0127] On the other hand, when the fire alarm control unit 48 of the main CPU 26 determines that a black smoke fire has occurred because the ratio R of the smoke detection values ​​A1, A2 falls below the ratio threshold value Rth = 5, it determines that black smoke has been generated by a rapidly expanding burning fire and that the danger level is high, and therefore performs control to output a fire alarm indicating a black smoke fire regardless of the presence of an intruder.

[0128] In addition, the fire alarm control unit 48 determines that a non-fire factor has occurred when the ratio R of the smoke detection values ​​A1, A2 becomes equal to or greater than the non-fire factor threshold RSth=12, and when it determines that there is no intruder detected by the security system 200, it performs control to withhold and not output a warning alarm indicating a non-fire factor.

[0129] If the non-fire cause is not eliminated even after a predetermined time has elapsed, the fire control unit 48 may cancel the suspension of the warning output and output a warning indicating the non-fire cause.

[0130] Other configurations and functions of the fire alarm system 1 are the same as those in the embodiment of FIG. 1, so the same reference numerals are used and the description thereof is omitted.

[0131] [Modifications of the present invention] (Photoelectric smoke detector) The above embodiment takes as an example a photoelectric smoke detector with a smoke detection section structure having one light-emitting element and two light-receiving elements, as shown in Figure 4, but is not limited to this and may be any photoelectric smoke detector with a smoke detection section structure that can obtain first and second smoke detection values ​​A1, A2 by setting different wavelengths and scattering angles, for example, a photoelectric smoke detector with a smoke detection section structure having two light-emitting elements and one light-receiving element as shown in Patent Document 2.

[0132] In addition, in the above embodiment, when the photoelectric smoke detector receives a batch AD conversion signal from the receiver, it detects the first and second smoke detection values ​​A1, A2 by driving the light-emitting element to emit light. However, the photoelectric smoke detector may itself detect the first and second smoke detection values ​​A1, A2 by intermittently driving the light-emitting element to emit light at a predetermined cycle, regardless of instructions from the receiver.

[0133] (P-type fire alarm system) The above embodiment takes as an example an R-type fire alarm system that monitors for fires by sending and receiving signals between a receiver and an addressed photoelectric smoke detector, but it may also be a P-type fire alarm system that, when the photoelectric smoke detector is activated, sends a white smoke fire signal, a black smoke fire signal or a non-fire cause signal to the receiver without receiving instructions from the receiver, and outputs a white smoke fire alarm, a black smoke fire alarm, or a non-fire alarm caution alarm.

[0134] In such P-type fire alarm systems, the photoelectric smoke detector sends an alarm current to the signal line from the receiver, thereby transmitting a white smoke fire signal, black smoke fire signal or non-fire cause signal to the receiver. In order to distinguish between the white smoke fire signal, black smoke fire signal or non-fire cause signal, a specific frequency signal or pulse code signal is superimposed on the alarm current, allowing the receiver to distinguish between the smoke fire signal, black smoke fire signal or non-fire cause signal and output a white smoke fire alarm, black smoke fire alarm or non-fire cause caution alarm.

[0135] In addition, the interlocking control of control devices such as local sound devices, exhaust devices, and fire extinguishing devices in a P-type fire alarm system is P-type interlocking control performed on a line-by-line basis.

[0136] (Judgment of Non-Fire Causes) In addition to the judgment of white smoke and black smoke, the above-described embodiment also performs the judgment of non-fire causes. However, it is also possible to perform only the judgment of white smoke and black smoke without performing the judgment of non-fire causes.

[0137] (Fire Alarm Equipment) The above-described embodiment takes a wired system in which a photoelectric smoke detector is connected to a signal line from a receiver as an example, but a wireless system in which the receiver and the photoelectric smoke detector are connected by a wireless line may also be used.

[0138] (Comparison Judgment) In the above-described embodiment, for example, as the comparison of the magnitudes of the ratio R and the ratio threshold value Rth, the cases of R≧Rth and R<Rth are shown. However, this is not limiting, and the comparison of the magnitudes of the cases of R>Rth and R≦Rth may also be used. The same applies to the comparison of the magnitudes of other values.

[0139] (Others) Further, the present invention includes appropriate modifications that do not impair its object and advantages, and furthermore, is not limited by the numerical values shown in the above-described embodiment.

Explanation of Reference Numerals

[0140] 1: Fire alarm equipment 10: Receiver 12, 12-1 to 12-3: Signal lines 14: Photoelectric smoke detector 16: Repeater 18: Area sound device 20: Exhaust device 22: Fire door 26: Main CPU 28-1 to 28-3: Sub CPU boards 30: Sub CPU 32: Transmission unit 34: Serial transfer bus 36: Display 38: Display unit 40: Operation unit 42: Acoustic alarm unit 44: Transfer reporting unit 45,114,208: Communication adapter 46: Transmission control section 48: Fire alarm control unit 50: Sensor control unit 52: Transmission section 54: Power supply section 56: Light emitting driver 60: Smoke Detection Department 62: Light emitting element 62a, 64a, 66a: Optical axis 64: First light receiving element 66: Second light receiving element 68, 70: Amplification circuit section 80: Human sensor 100: Entrance / Exit Management System 102: Central device 104: Client 106: LAN line 108: Local control panel 110: Card reader 112: Electric lock 200:Security system 202: Security receiver panel 206: Security sensor

Claims

1. A fire alarm system that monitors and issues an alarm for fires in a restricted area, a fire detector that detects a fire in the warning area and transmits a fire signal; a human detection means for detecting the presence or absence of a human in the alert area and transmitting a detection signal; a fire alarm control unit that controls an alarm operation based on the fire signal from the fire detector and the detection signal from the human detection means; Equipped with The fire alarm control unit is When it is determined that a fire with a low level of danger and the presence of a person in the warning area are present based on the fire signal and the detection signal, a caution alarm is output without outputting a fire alarm; outputting a fire alarm when determining that the fire is of low risk and that no one is present in the warning area based on the fire signal and the detection signal; When a fire with a high risk of danger is determined based on the fire signal, a fire alarm is output regardless of whether or not a person is present in the warning area; Distinguishing non-fire causes based on the fire signal; when it is determined that a person is present in the alert area based on the detection signal after determining that the non-fire factor has occurred, output of a warning indicating the occurrence of a non-fire factor is suspended; This fire alarm system is characterized in that when it determines that there is no one in the alert area based on the detection signal after determining that there is a non-fire cause, it outputs a warning alarm indicating the occurrence of the non-fire cause.

2. The fire alarm system according to claim 1, The fire alarm control unit outputs different fire alarms according to the determined degree of fire danger.

3. In the fire alarm system according to claim 1 or 2, A fire alarm system characterized in that low-risk fires determined by the fire alarm control unit include white smoke fires, and high-risk fires determined by the fire alarm control unit include black smoke fires.

Images