Smoke sensor

Abstract

The present invention provides a smoke detector that, when a filter for capturing dust is removed or displaced, does not falsely detect, as smoke, dust flowing into the smoke detector. A smoke detector 11 comprises a light-emitting unit 111 and a light-receiving unit 113 that are disposed in a detection region S1. The smoke detector 11: determines whether air contains smoke by receiving, via the light-receiving unit 113, scattered light which is the light emitted by the light-emitting unit 111 and then scattered by particles contained in the air flowing into the detection region S1 from an external space; and on the basis of the determination results, detects smoke generation in the external space. The smoke detector 11 comprises: a filter 116 that captures and removes dust contained in the air flowing into the detection region S1 from the external space; an openable cover 1102 that separates a housing space, which houses the filter 116, from the outside; and a switch 117 that detects attachment / removal of the filter 116. A control unit 118 stops processing for smoke detection in a case where the switch 117 detects that the filter 116 has been removed.

Description

Technical Field

[0001] The present invention relates to a technology for detecting smoke.

Background Art

[0002] There is a smoke detector that detects the occurrence of smoke in the external space by detecting particles contained in the air flowing from the external space into the detection area.

[0003] When air containing dust flows into the detection area for detecting smoke in the smoke detector, there is a risk that the smoke detector may misidentify the dust as smoke particles. Therefore, most smoke detectors include a filter for capturing dust contained in the air on the air flow path from the external space to the detection area.

[0004] As a patent document disclosing a smoke detector including a filter, for example, there is Patent Document 1. Patent Document 1 describes a smoke detection device in which a suction unit for sucking outside air, a detection unit for detecting smoke particles from the sucked outside air, a filter for removing dust from the sucked outside air, and a filter unit including a casing surrounding the filter are unitized to be individually detachable from the casing.

[0005] The smoke detection device described in Patent Document 1 is easy to identify a failure site, perform maintenance, replacement, etc.

[0006] Moreover, most smoke detectors include a casing, and include a mechanism for detecting particles in an accommodation space formed inside the casing. Most such smoke detectors include an openable and closable cover so that an operator can check or replace the state of the components inside the casing for the purpose of maintenance or the like.

[0007] One example of a patent document disclosing a smoke detector equipped with an openable and closable cover is Patent Document 2. Patent Document 2 describes a photoelectric smoke detector comprising an optical case that blocks external light, a laser light source that emits light within the optical case, a light-receiving element that receives scattered light scattered by smoke particles present in the smoke detection section, and a fire determination unit that determines that a fire has occurred when the level of the output signal of the light-receiving element is above a threshold.

[0008] The smoke detector described in Patent Document 2 has an optical case comprising a box and an openable and closable optical cover that closes the opening of the box. Furthermore, the smoke detector described in Patent Document 2 is characterized by having a control unit that either stops the emission of light from the laser light source when the optical cover is opened, or lengthens the emission period from the laser light source compared to when the cover is closed. The smoke detector described in Patent Document 2, having such a configuration, can avoid the risk of laser light entering the eyes of a worker opening the optical cover and damaging their eyes. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Publication No. 2008-108140 [Patent Document 2] Japanese Patent Publication No. 2010-237738 [Overview of the project] [Problems that the invention aims to solve]

[0010] When workers temporarily remove the filter for replacement or inspection of other parts, dust-laden air flows into the sensing area without passing through the filter. Also, when workers open the cover that surrounds the filter to inspect parts inside the smoke detector, the filter, which was held in place by the cover blocking the airflow path, becomes loose, meaning the filter moves out of its functional position, and dust-laden air may flow into the sensing area through the gap. As a result, there is a risk that the smoke detector may mistake dust for smoke.

[0011] In view of the above circumstances, the present invention provides a smoke detector that does not misinterpret dust flowing in as smoke when the dust-capturing filter is removed or displaced. [Means for solving the problem]

[0012] To solve the above problems, the present invention proposes a smoke detector that detects the generation of smoke in an external space by sensing particles contained in air flowing into a sensing area from an external space, comprising: sensing means for sensing particles in the air within the sensing area and detecting smoke based on the sensing result; a filter disposed on the airflow path of the air flowing into the sensing area and capturing dust contained in the air; attachment / detachment detection means for detecting the attachment / detachment of the filter; and control means for stopping at least a part of the operation for detecting smoke in the sensing means when the attachment / detachment detection means detects that the filter has changed from an attached state to a detached state. [Effects of the Invention]

[0013] According to the present invention, smoke detection is stopped when the dust-capturing filter is removed or displaced, so that incoming dust is not mistakenly detected as smoke. [Brief explanation of the drawing]

[0014] [Figure 1] A diagram showing the configuration of a smoke detection system according to one embodiment. [Figure 2] A schematic diagram showing the configuration of a smoke detector according to one embodiment. [Figure 3] A diagram showing the configuration of a computer used as hardware for a control unit according to one embodiment. [Figure 4] A diagram showing the functional configuration of a control unit according to one embodiment. [Figure 5] This diagram shows the flow of processing performed by a control means according to one embodiment when the attachment / detachment signal changes. [Figure 6]A diagram schematically showing the configuration of a smoke detector according to a modified example.

[0015] [Embodiment] A smoke detection system 1 according to an embodiment of the present invention will be described below. FIG. 1 is a diagram showing the configuration of the smoke detection system 1. The smoke detection system 1 includes a smoke detector 11 and a host system 12.

[0016] The smoke detector 11 is arranged in a space to be monitored for smoke generation (hereinafter referred to as "monitoring space"), takes in the air in the monitoring space, senses the smoke if the taken-in air contains smoke, and when the smoke is sensed, transmits an alarm of smoke generation to the host system 12.

[0017] In FIG. 1, the number of smoke detectors 11 included in the smoke detection system 1 is one, but the number of smoke detectors 11 included in the smoke detection system 1 varies according to the number and size of the monitoring spaces.

[0018] The host system 12 may be any of a monitoring terminal device, a smoke alarm panel, a central monitoring system, etc. The host system 12 and the smoke detector 11 are communicatively connected via a wired, wireless, or a mixed communication medium thereof, and can perform data communication with each other.

[0019] Since the host system 12 is the same as the host system according to the prior art, its description is omitted.

[0020] FIG. 2 is a diagram schematically showing the configuration of the smoke detector 11. FIG. 2(a) schematically shows the smoke detector 11 in a state where the filter 116 is attached (hereinafter referred to as "attached state") and the cover 1102 is closed (hereinafter referred to as "closed state"), and FIG. 2(b) schematically shows the smoke detector 11 in a state where the filter 116 is removed (hereinafter referred to as "detached state") and the cover 1102 is opened (hereinafter referred to as "opened state").

[0021] The smoke detector 11 comprises a housing 110, a light-emitting unit 111, a light-emitting unit 112, a light-receiving unit 113, a lens 114, a fan 115, a filter 116, a switch 117, and a control unit 118.

[0022] The housing 110 is a container that forms a space inside. In the example shown in Figure 2, the housing 110 has a partition plate 1101 that divides the internal space into a sensing area S1, which is a region for detecting smoke, and a housing area S2, which houses the control unit 118.

[0023] Furthermore, the wall portion of the housing 110 that forms the sensing area S1 is provided with an intake port P, which functions as an inlet for air to flow from the external space into the internal space, and an exhaust port Q, which functions as an outlet for air to flow out from the internal space into the external space.

[0024] Furthermore, a portion of the wall of the housing 110 is a cover 1102 that can be opened and closed. Workers open the cover 1102 to inspect, replace, or otherwise access the internal components of the smoke detector 11. In the example shown in Figure 2, the air intake P is provided in the cover 1102, but the air intake P may also be provided in a part of the wall of the housing 110 other than the cover 1102.

[0025] The light-emitting units 111 and 112 each have, for example, LEDs, and emit light from the LEDs under the control of the control unit 118. The light emitted by the light-emitting unit 111 is for detecting smoke within the sensing area S1. The light-emitting unit 111 emits light towards the airflow path from the intake port P to the exhaust port Q. Furthermore, the light-emitting unit 111 is positioned so as not to face the light-receiving unit 113, so that the emitted light does not directly enter the light-receiving unit 113.

[0026] On the other hand, the light emitted by the light-emitting unit 112 is used to measure the dirt on the lens 114. The light-emitting unit 112 is positioned, for example, in a direction along the airflow path from the intake port P to the exhaust port Q when viewed from the light-receiving unit 113, and emits light in a direction that directly incidents on the light-receiving unit 113. Also, for example, the distance from the light-emitting unit 112 to the light-receiving unit 113 is shorter than the distance from the light-emitting unit 111 to the light-receiving unit 113. Therefore, the light emitted from the light-emitting unit 112 and directed toward the light-receiving unit 113 is less affected by particles in the air flowing into the sensing area S1 compared to the light emitted from the light-emitting unit 111 and directed toward the light-receiving unit 113.

[0027] The light receiving unit 113, for example, has a photodiode and receives scattered light from the light emitting unit 111 scattered by particles in the sensing region S1 and the light emitting unit 112, which is focused by the lens 114, and outputs a light intensity signal indicating the intensity of the received light to the control unit 118.

[0028] The lens 114 collects a portion of the light emitted from the light-emitting units 111 and 112 and guides it to the light-receiving unit 113.

[0029] The fan 115 operates under the control of the control unit 118 and, through its rotating blades, generates an airflow that flows from the outside space through the intake port P into the sensing area S1 and out through the exhaust port Q into the outside space.

[0030] The filter 116 comprises a cylindrical casing and a filter body positioned inside the casing. The filter 116 is positioned in the airflow path from the intake port P to the exhaust port Q, and the filter body captures dust contained in the air moving from the outside space to the sensing area S1, preventing dust from entering the sensing area S1. The cover 1102 is an openable and closable cover that separates the housing space containing the filter 116 (in this case, the space between the fan 115 and the cover 1102) from the outside, and plays a role in enabling the filter 116 to perform its function by keeping the filter 116 attached when the cover is closed.

[0031] Switch 117 (an example of an attachment / detachment detection means) is a component that detects the attachment and detachment of the filter 116, i.e., the attached state and the detached state. Switch 117 has a button 1171 that is biased toward the filter 116. Switch 117 outputs an attachment signal to the control unit 118 when the filter 116 is attached and the button 1171 is pressed, and outputs a detachment signal to the control unit 118 when the filter 116 is detached and the button 1171 is not pressed. Hereinafter, the attachment signal and the detachment signal together will be referred to as the attachment / detachment signal.

[0032] The control unit 118 is a device that controls the operation of the smoke detector 11, etc. The hardware of the control unit 118 is, for example, a computer, and the control unit 118 is realized when the computer performs processing according to a program for the control unit 118.

[0033] Figure 3 shows the configuration of the computer 10 used as the hardware for the control unit 118. The computer 10 includes a processor 101 for processing various data, a memory 102 for storing various data, an input / output interface 103 for exchanging signals with components such as the light-emitting unit 111 of the smoke detector 11, and a communication interface 104 for sending and receiving data with an external device (in this case, a higher-level system 12).

[0034] Figure 4 shows the functional configuration of the control unit 118. That is, the control unit 118, equipped with the components shown in Figure 4, is realized when the computer 10 performs processing according to the program for the control unit 118. The functional components of the control unit 118 are described below.

[0035] The light emission instruction means 1181 instructs the light emission unit 111 to emit light. The light emission instruction means 1181 instructs the light emission unit 111 to emit light, for example, at predetermined intervals, except when the smoke detector 11 is operating and has been ordered to stop operation by an instruction from the control means 1180 (described later) until it is ordered to restart operation.

[0036] The light emission instruction means 1182 instructs the light emission unit 112 to emit light. Except for the period between when the operation is stopped by an instruction from the control means 1180 (described later) and when the operation is restarted, the light emission instruction means 1182 instructs the light emission unit 112 to emit light, for example, at predetermined intervals.

[0037] The light intensity signal acquisition means 1183 acquires the light intensity signal output from the light receiving unit 113.

[0038] The smoke detection means 1184 determines whether or not smoke is present in the air around the smoke detector 11 by determining whether or not the light intensity indicated by the light intensity signal acquired by the light intensity signal acquisition means 1183 satisfies predetermined conditions for smoke detection. The predetermined conditions for smoke detection include, for example, a condition in which the light intensity signal remains within a reference range indicating the presence of smoke for a predetermined period of time or longer.

[0039] The intensity of light received by the light-receiving unit 113 is affected by the degree of contamination of the lens 114. Therefore, the smoke detection means 1184 modifies the smoke detection conditions (e.g., reference range) according to the degree of contamination of the lens 114 measured by the contamination measurement means 1185.

[0040] If the smoke detection means 1184 determines that smoke is present, it generates smoke generation notification data to notify the system of smoke generation. The smoke generation notification data generated by the smoke detection means 1184 is transmitted to the higher-level system 12 via the communication means 1186.

[0041] Furthermore, the smoke detection means 1184 continues processing for smoke detection even while the contamination measurement is being performed by using conditions different from normal (for example, a different reference range from normal) while the light-emitting unit 112 is irradiating with light for contamination measurement. However, if the time during which the light-emitting unit 112 is irradiating with light for contamination measurement is short enough that no substantial problem occurs even if smoke detection is not performed during that time, the smoke detection means 1184 may stop processing for smoke detection while the light-emitting unit 112 is irradiating with light for contamination measurement.

[0042] The light emission instruction means 1181, light emission unit 111, light receiving unit 113, light intensity signal acquisition means 1183, and smoke determination means 1184 constitute a sensing means that senses particles in the air within the sensing area S1 and detects smoke based on the results of the sensing.

[0043] The dirt measuring means 1185 measures the dirt on the lens 114 based on the amount of change in the light intensity indicated by the light intensity signal acquired by the light intensity signal acquisition means 1183 when the light-emitting unit 112 changes from a non-emitting state to an emitting state. The dirt measuring means 1185 stores data that shows the correspondence between the degree of dirt on the lens 114 and the degree to which the light intensity received by the light-receiving unit 113 changes between when the light-emitting unit 112 is off and when it is emitting, according to that dirt, and measures the degree of dirt on the lens 114 by referring to this data.

[0044] The dirt measurement means 1185 generates dirt notification data that indicates the measured degree of dirt. The dirt notification data generated by the dirt measurement means 1185 is transmitted to the higher-level system 12 by the communication means 1186. As previously described, the dirt notification data generated by the dirt measurement means 1185 is also used by the smoke determination means 1184 to modify the conditions for smoke detection.

[0045] Furthermore, if the smoke detection means 1184 stops processing for smoke detection while the light-emitting unit 112 is emitting light for measuring dirt, the light emission instruction means 1182 may instruct the light-emitting unit 111 to stop emitting light during that time, and the dirt measurement means 1185 may measure the degree of dirt on the lens 114 based on the intensity of light measured by the light-receiving unit 113, which receives only the light emitted from the light-emitting unit 112.

[0046] The light emission indicator means 1182, the light emission unit 112, the light receiving unit 113, the light intensity signal acquisition means 1183, and the dirt measurement means 1185 constitute a dirt detection means for detecting dirt within the sensing area S1.

[0047] The communication means 1186 transmits and receives various types of data with the higher-level system 12. For example, as described above, the communication means 1186 transmits smoke generation notification data generated by the smoke detection means 1184 and dirt notification data generated by the dirt measurement means 1185 to the higher-level system 12.

[0048] A user of the higher-level system 12 (for example, the administrator of the smoke detection system 1) can learn from the smoke detection notification data transmitted from the smoke detector 11 that there is a high probability of a fire occurring in the monitored space where the smoke detector 11 is located. In addition, a user of the higher-level system 12 can learn from the dirt notification data transmitted from the smoke detector 11 that the lens 114 of the smoke detector 11 is dirty, and can request workers to clean the lens 114 as needed.

[0049] The connection / disconnection signal acquisition means 1187 acquires connection / disconnection signals from the switch 117. The operation instruction means 1188 instructs the fan 115 to start and stop operation.

[0050] The timing means 1189 continuously measures the current time based on a clock signal generated by a clock provided by the processor 101, for example, and generates a time signal indicating the measured current time.

[0051] The control means 1180 controls the operation of the light emission indicator means 1181, the light emission indicator means 1182, the smoke detection means 1184, the dirt measurement means 1185, and the operation instruction means 1188.

[0052] When the attachment / detachment signal received from the switch 117 via the attachment / detachment signal acquisition means 1187 changes as an operator attaches or detaches the filter 116, the control means 1180 instructs the light emission indicator means 1181, etc., to stop or restart the operation.

[0053] Figure 5 shows the flow of processing performed by the control means 1180 when the attachment / detachment signal changes.

[0054] When the control means 1180 detects a change in the attachment / detachment signal, it determines whether the change indicates a change from an attachment signal to a detachment signal, or a change from a detachment signal to an attachment signal (step S101).

[0055] In step S101, if it is determined that the change in the attachment / detachment signal indicates a change from the attached state to the detached state (step S101; "1"), the control means 1180 performs the following processing (step S201). (1) The light emission instruction means 1181 is prohibited from issuing a light emission instruction to the light emission unit 111. (2) The light emission instruction means 1182 is prohibited from issuing a light emission instruction to the light emission unit 112. (3) The smoke detection means 1184 is ordered to stop the smoke detection process. (4) The dirt measurement means 1185 is ordered to stop the process for measuring dirt. (5) The operation instruction means 1188 is instructed to stop the operation of the fan 115.

[0056] Following the processing by the control means 1180 in step S201, the light-emitting units 111 and 112 cease to emit light, and the fan 115 stops rotating its blades. In addition, the communication means 1186 stops transmitting smoke generation notification data and dirt notification data to the higher-level system 12.

[0057] After completing the process in step S201, the control means 1180 terminates the process according to the flow shown in Figure 5.

[0058] In step S101, if it is determined that the change in the attachment / detachment signal indicates a change from the detached state to the attached state (step S101; "2"), the control means 1180 first instructs the operation instruction means 1188 to restart the operation of the fan 115 (step S301). Following the processing by the control means 1180 in step S301, the fan 115 restarts the rotation of its blades.

[0059] Next, the control means 1180 determines whether a predetermined time (for example, 1 minute) has elapsed (step S302). If it is determined in step S302 that the predetermined time has not elapsed (step S302; "No"), the control means 1180 repeats the determination in step S302.

[0060] The time between the execution of step S301 and the determination in step S302 being "Yes" is the time required for the airflow generated by the fan 115 to expel dust that has entered the sensing area S1 to the outside through the air intake P. In other words, if the filter 116 is removed by an employee, air containing dust may flow into the sensing area S1. Even in such a case, once the filter 116 is installed, the fan 115 operates for a predetermined time before the smoke detection process by the smoke detection means 1184 is resumed, thus expelling the dust that has entered the sensing area S1.

[0061] If it is determined in step S302 that a predetermined time has elapsed (step S302; "Yes"), the control means 1180 performs the following processing (step S303). (1) The light emission instruction means 1181 is authorized to issue a light emission instruction to the light emission unit 111. (2) The light emission instruction means 1182 is authorized to issue a light emission instruction to the light emission unit 112. (3) The smoke detection means 1184 is ordered to resume the smoke detection process. (4) The dirt measurement means 1185 is ordered to resume the process for measuring dirt.

[0062] Following the processing by the control means 1180 in step S303, the light-emitting units 111 and 112 resume emitting light, the smoke detection means 1184 resumes processing for smoke detection, and the dirt measurement means 1185 resumes processing for dirt measurement. If smoke is generated in the monitoring space, the communication means 1186 will send smoke generation notification data to the higher-level system 12, and if dirt measurement is performed, the communication means 1186 will send dirt notification data to the higher-level system 12.

[0063] According to the smoke detection system 1 described above, even if a worker removes the filter 116, dust entering the detection area S1 will not cause false detection of smoke or mismeasurement of dirt.

[0064] Furthermore, according to the smoke detection system 1 described above, after the worker installs the filter 116, only the fan 115 restarts operation first, and after dust is discharged from the sensing area S1, the smoke detection and dirt measurement operations resume. Therefore, dust floating in the sensing area S1 immediately after the installation of the filter 116 does not cause false smoke detection or false dirt measurement.

[0065] [Differentiation] The embodiments described above are specific examples of the present invention and can be modified in various ways within the scope of the technical idea of ​​the present invention. Examples of such modifications are shown below. Two or more of the following modifications may be combined as appropriate.

[0066] (1) In the above-described embodiment, the attachment and detachment of the filter 116 is directly detected by the switch 117. Alternatively, a configuration in which the attachment and detachment of the filter 116 is indirectly detected may be adopted.

[0067] Figure 6 is a schematic diagram showing the configuration of an example of a smoke detector 11 according to such a modification. The smoke detector 11 shown in Figure 6 differs from the smoke detector 11 according to the above-described embodiment in that the switch 117 does not directly detect the attachment or detachment of the filter 116, but indirectly detects the attachment or detachment of the filter 116 by detecting the opening and closing of the cover 1102 that covers the filter 116.

[0068] In other words, in this modified example, the button 1171 of the switch 117 is biased toward the cover 1102. The switch 117 outputs a "click" signal to the control unit 118 indicating that the filter 116 is firmly held in place by the cover 1102 while the cover 1102 is closed and the button 1171 is pressed. On the other hand, the switch 117 outputs a "disconnect" signal to the control unit 118 indicating that the filter 116 is not held by the cover 1102 and that the filter 116 may have come out of its predetermined position while the cover 1102 is open and the button 1171 is not pressed.

[0069] In other words, in this modified example, the switch 117 (an example of an attachment / detachment detection means) detects the open state of the cover 1102 as the state in which the filter 116 has been removed, and the closed state of the cover 1102 as the state in which the filter 116 has been attached.

[0070] According to this modified version, even if, for example, the cover 1102 is opened and the filter 116 is displaced, dust entering the sensing area S1 will not cause false detection of smoke or mismeasurement of dirt.

[0071] (2) In the above-described embodiment, a switch 117 is used as the attachment / detachment detection means for detecting the attachment / detachment of the filter 116. The type of attachment / detachment detection means for detecting the attachment / detachment of the filter 116 is not limited to a switch. For example, an object detection sensor using light may be used as the attachment / detachment detection means for detecting the attachment / detachment of the filter 116.

[0072] (3) In the above-described embodiment, when a change in the filter 116 from the attached state to the detached state is detected, the control means 1180 stops all of the following: light emission by the light-emitting unit 111, light emission by the light-emitting unit 112, smoke detection processing by the smoke determination means 1184, dirt measurement processing by the dirt measurement means 1185, and operation of the fan 115. When a change in the filter 116 from the attached state to the detached state is detected, the control means 1180 does not need to stop all of these, but only needs to stop at least a part of the operation for detecting smoke.

[0073] For example, if the light emitted by the light-emitting unit 111 or 112 is not dangerous to a worker's eyes, then when the filter 116 is removed, the control means 1180 does not need to prohibit the light emission instruction means 1181 from issuing a light emission instruction to the light-emitting unit 111, or prohibit the light emission instruction means 1182 from issuing a light emission instruction to the light-emitting unit 112.

[0074] (4) In the above-described embodiment, when a change in the filter 116 from a detached state to an attached state is detected, the control means 1180 first instructs the fan 115 to restart operation, and then suspends the restart of all of the following for a predetermined time: light emission by the light-emitting unit 111, light emission by the light-emitting unit 112, smoke detection processing by the smoke determination means 1184, and dirt measurement processing by the dirt measurement means 1185. Alternatively, when a change in the filter 116 from a detached state to an attached state is detected, the control means 1180 may, at the same time as instructing the fan 115 to restart operation, for example, allow the light emission instruction means 1181 to issue a light emission instruction to the light-emitting unit 111, or allow the light emission instruction means 1182 to issue a light emission instruction to the light-emitting unit 112.

[0075] (5) In the embodiments described above, the hardware of the control unit 118 was assumed to be a computer, but the control unit 118 may be configured as a dedicated device having an integrated circuit such as an ASIC or FPGA. [Explanation of symbols]

[0076] 1...Smoke detection system, 10...Computer, 11...Smoke detector, 12...Higher-level system, 101...Processor, 102...Memory, 103...Input / output interface, 104...Communication interface, 110...Housing, 111...Light-emitting unit, 112...Light-emitting unit, 113...Light-receiving unit, 114...Lens, 115...Fan, 116...Filter, 117...Switch, 118...Control unit, 1101...Partition plate, 1102...Cover, 1171...Button, 1180...Control means, 1181...Light emission indicator means, 1182...Light emission indicator means, 1183...Light intensity signal acquisition means, 1184...Smoke determination means, 1185...Dirt measurement means, 1186...Communication means, 1187...Attachment / detachment signal acquisition means, 1188...Operation instruction means, 1189...Timekeeping means.

Claims

1. A smoke detector that detects the generation of smoke in the external space by sensing particles contained in the air flowing into the sensing area from the external space, A sensing means that senses particles in the air within the sensing area and detects smoke based on the results of the sensing, A filter is placed on the airflow path of the air that flows into the sensing area and captures dust contained in the air, A means for detecting the attachment or detachment of the filter, When the attachment / detachment detection means detects that the filter has changed from an attached state to an detached state, the control means stops the smoke detection by the sensing means. A smoke detector equipped with the following features.

2. A smoke detector that detects the generation of smoke in an external space by sensing particles contained in the air flowing into the sensing area from the external space, A sensing means that senses particles in the air within the sensing area and detects smoke based on the results of the sensing, A filter is placed on the airflow path of the air that flows into the sensing area and captures dust contained in the air, A means for detecting the attachment or detachment of the filter, When the attachment / detachment detection means detects that the filter has changed from an attached state to an detached state, the sensing means is equipped with a control means that stops at least a part of the operation for detecting smoke. A removable cover separates the housing space containing the aforementioned filter from the outside. Equipped with, The attachment / detachment detection means detects the open state of the cover as the state in which the filter has been removed, and the closed state of the cover as the state in which the filter has been attached. Smoke detector.

3. A smoke detector that detects the generation of smoke in an external space by sensing particles contained in the air flowing into the sensing area from the external space, A sensing means that senses particles in the air within the sensing area and detects smoke based on the results of the sensing, A filter is placed on the airflow path of the air that flows into the sensing area and captures dust contained in the air, A means for detecting the attachment or detachment of the filter, When the attachment / detachment detection means detects that the filter has changed from an attached state to an detached state, the sensing means is equipped with a control means that stops at least a part of the operation for detecting smoke. A dirt detection means for detecting dirt within the sensing area and Equipped with, When the attachment / detachment detection means detects that the filter has changed from an attached state to a detached state, the control means stops the operation of the dirt detection means. Smoke detector.

4. The sensing means has a light-emitting part that emits light, When the attachment / detachment detection means detects that the filter has changed from an attached state to a detached state, the control means stops the light emission from the light-emitting unit. A smoke detector according to any one of claims 1 to 3.

5. A fan that generates an airflow from the outside toward the sensing area. Equipped with, When the attachment / detachment detection means detects that the filter has changed from an attached state to a detached state, the control means stops the operation of the fan. A smoke detector according to any one of claims 1 to 4.

6. A smoke detector that detects the generation of smoke in an external space by sensing particles contained in the air flowing into the sensing area from the external space, A sensing means that senses particles in the air within the sensing area and detects smoke based on the results of the sensing, A filter is placed on the airflow path of the air that flows into the sensing area and captures dust contained in the air, A means for detecting the attachment or detachment of the filter, When the attachment / detachment detection means detects that the filter has changed from an attached state to an detached state, the sensing means is equipped with a control means that stops at least a part of the operation for detecting smoke. A fan that generates an airflow from the outside toward the sensing area Equipped with, When the attachment / detachment detection means detects that the filter has changed from an attached state to a detached state, the control means stops the operation of the fan. When the attachment / detachment detection means detects that the filter has changed from a detached state to an attached state, the control means restarts the operation of the fan, and after a predetermined time has elapsed, restarts the operation of the sensing means to detect smoke that was stopped. Smoke detector.

7. A fan that generates an airflow from the outside toward the sensing area. Equipped with, When the attachment / detachment detection means detects that the filter has changed from an attached state to a detached state, the control means stops the operation of the fan. When the attachment / detachment detection means detects that the filter has changed from a detached state to an attached state, the control means restarts the operation of the fan, and after a predetermined time has elapsed, instructs the dirt detection means to restart the stopped operation. The smoke detector according to claim 3.

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