Fire alarm

Abstract

To provide a technology for initial fire extinguishing.SOLUTION: A fire alarm 200 includes at least a detector 214, a holder 220, and a housing. The detector 214 detects a fire. The holder 220 holds a fire extinguishing agent. The housing of the fire alarm 200 accommodates at least the detector 214 and the holder 220. The housing can be deformed between a first shape for holding the fire extinguishing agent in the holder 220 and a second shape for releasing the fire extinguishing agent out of the housing 310 from the holder 220.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to fire alarm technology, and more particularly to fire alarms for detecting fires. [Background technology]

[0002] The multiple fire alarms in an alarm system are classified into a master station and the remaining slave stations. When a slave station detects a fire, it notifies the master station by wireless communication. The master station notifies the other slave stations of the fire, and each slave station reports the fire (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-71561 A Summary of the Invention [Problem to be solved by the invention]

[0004] An alarm system is used to notify the occurrence of a fire. However, even if a fire is notified, if a fire extinguisher is not installed in the vicinity, the fire cannot be put out in its early stages.

[0005] The present disclosure has been made in consideration of these circumstances, and has an object to provide a technique for performing initial fire extinguishing. [Means for solving the problem]

[0006] In order to solve the above problems, a fire alarm according to an embodiment of the present disclosure includes a detection unit that detects a fire, a holding unit that holds an extinguishing agent, and a housing that houses the detection unit and the holding unit. The housing is deformable between a first shape in which the holding unit holds the extinguishing agent and a second shape in which the holding unit releases the extinguishing agent to the outside of the housing.

[0007] Any combination of the above components, and conversion of the present disclosure into a method, device, system, recording medium, computer program, etc. are also valid aspects of the present disclosure. Effect of the Invention

[0008] According to the present disclosure, initial fire extinguishing can be performed. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing a configuration of an alarm system according to an embodiment. [Diagram 2] FIG. 2 is a diagram showing the configuration of the fire alarm device of FIG. [Diagram 3] 3(a)-(c) are diagrams showing the structure of the fire alarm of FIG. [Figure 4] 4(a)-(b) are diagrams showing an overview of the release of extinguishing agent by the fire alarms of FIGS. 3(a)-(c). [Diagram 5] 5(a)-(e) are diagrams showing an overview of the release of extinguishing agent by the fire alarm according to the first modification. [Figure 6] 6(a)-(b) are diagrams showing an overview of the release of extinguishing agent by the fire alarm according to the second modification. [Figure 7] 7(a)-(c) are flow charts showing the modification procedure of the fire alarm of FIGS. 3(a)-(c). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Before describing the present disclosure in detail, an overview will be provided. This embodiment relates to an alarm system installed in facilities such as apartment buildings, detached houses, offices, hospitals, etc. In the alarm system, multiple fire alarms are connected to a gateway. The gateway performs wireless communication with each fire alarm. When a fire alarm detects the occurrence of a fire, it transmits the detection result to the gateway. When the gateway receives the detection result, it selects one or more fire alarms that will sound, and transmits an instruction to sound to the selected one or more fire alarms. When the fire alarm receives the instruction to sound, it sounds.

[0011] In order to enable early extinguishing of a fire in such an alarm system, a fire alarm holds a fire extinguishing agent inside. The fire alarm is attached to a ceiling or a wall, and sounds when a fire breaks out. In such a situation, a user removes the fire alarm and throws it at the fire scene. The fire alarm deforms when subjected to an external impact, and releases the held fire extinguishing agent to the outside.

[0012] 1 shows the configuration of an alarm system 1000. The alarm system 1000 includes a gateway 100 and a first fire alarm 200a to a fourth fire alarm 200d collectively referred to as fire alarms 200. The number of gateways 100 is not limited to "1", and the number of fire alarms 200 is not limited to "4".

[0013] The alarm system 1000 is applied to facilities such as homes, offices, and commercial facilities, and is a system that detects fires and notifies the occurrence of a fire. The multiple fire alarms 200 are, for example, residential fire alarms and are equipped with fire detection sensors. The multiple fire alarms 200 are installed, for example, on the ceiling of the facility, but may also be installed on the wall.

[0014] The first fire alarm device 200a to the fourth fire alarm device 200d are connected to the gateway 100a, and the gateway 100 and each fire alarm device 200 perform wireless communication. An address is assigned to each of the gateway 100 and the fire alarm device 200, and the address is used to specify the source and destination of a signal. For example, the gateway 100 stores its own address and each of the addresses of the first fire alarm device 200a to the fourth fire alarm device 200d, and the first fire alarm 200a stores the addresses of the first fire alarm device 200a and the gateway 100.

[0015] When the gateway 100 transmits a signal to the first fire alarm device 200a, the gateway 100 includes in the signal the address of the gateway 100 as the source address and the address of the first fire alarm device 200a as the destination address. The first fire alarm device 200a receives the signal. If the destination address included in the signal is the address of the first fire alarm device 200a, the first fire alarm device 200a processes the signal, and if the destination address is not the address of the first fire alarm device 200a, the first fire alarm device 200a discards the signal.

[0016] When the first fire alarm device 200a transmits a signal to the gateway 100, the signal contains the address of the first fire alarm device 200a as the source address and the address of the gateway 100 as the destination address. The gateway 100 receives the signal. Similar processing is performed in the gateway 100 and the other fire alarm devices 200.

[0017] In the alarm system 1000 configured as described above, "regular monitoring" and "fire detection" are performed. "Regular monitoring" is a process for confirming that no communication abnormalities occur in the alarm system 1000. In "regular monitoring", the fire alarm 200 transmits a notification signal, and the gateway 100 that receives the notification signal transmits a response signal. "Regular monitoring" is performed periodically, for example every 24 hours.

[0018] "Fire detection" is a process in which one or more fire alarms 200 sound an alarm when they detect the occurrence of a fire. In "fire detection", the fire alarm 200 that detects the occurrence of a fire transmits the detection result to the gateway 100, and the gateway 100 identifies the fire alarm 200 to sound based on the source address included in the detection result. The correspondence between the address and the information of the fire alarm 200 to sound is stored in advance in the gateway 100. The gateway 100 transmits an instruction to sound to the identified fire alarm 200, and the fire alarm 200 that receives the instruction to sound sounds.

[0019] For example, the gateway 100 stores a correspondence relationship between the address of the first fire alarm 200a and the information of the first fire alarm 200a and the second fire alarm 200b to be sounded. When the first fire alarm 200a detects the occurrence of a fire, it transmits the detection result to the gateway 100. When the gateway 100 receives the detection result, it confirms that the sender address included in the detection result is the address of the first fire alarm 200a. The gateway 100 identifies the first fire alarm 200a and the second fire alarm 200b based on the above-mentioned correspondence relationship. The gateway 100 transmits an instruction to sound to the identified first fire alarm 200a and second fire alarm 200b, and the first fire alarm 200a and the second fire alarm 200b that receive the instruction to sound sound sound.

[0020] It is required that such a fire alarm 200 be able to extinguish a fire in an initial stage. Below, a fire alarm 200 for realizing initial stage extinguishing is described. Fig. 2 shows the configuration of the fire alarm 200. The fire alarm 200 includes a communication unit 210, a control unit 212, a detection unit 214, an alarm unit 216, a holding unit 220, a setting unit 222, and a power supply unit 230.

[0021] The detection unit 214 is a fire detection sensor and detects a fire by a known technique. For example, the detection unit 214 may be an optical smoke detection sensor and may detect a fire by detecting smoke during a fire using diffuse reflection of light. For example, the detection unit 214 may be a heat detection sensor and may detect a fire by detecting heat during a fire. For example, the detection unit 214 may be a carbon monoxide detection sensor and may detect a fire by detecting the concentration of carbon monoxide generated by combustion during a fire. For example, the detection unit 214 may be an infrared detection sensor and may detect a fire by detecting infrared rays emitted by combustion during a fire. When the detection unit 214 detects a fire, it notifies the control unit 212 that a fire has been detected.

[0022] The control unit 212 controls the operation of the fire alarm 200. When the control unit 212 receives a notification from the detection unit 214, it generates a detection result for notifying the occurrence of a fire, and outputs the detection result to the communication unit 210. At that time, the control unit 212 stores the address of the gateway 100 with which it communicates and the address of the fire alarm 200, and uses these addresses when generating the detection result.

[0023] The communication unit 210 executes wireless communication with the gateway 100. For example, the communication unit 210 transmits a detection result generated in the control unit 212 to the gateway 100. The communication unit 210 also receives an instruction to sound a sound from the gateway 100. When the destination address included in the instruction to sound received by the communication unit 210 is the address of the fire alarm 200, the control unit 212 causes the notification unit 216 to sound a buzzer sound.

[0024] The holding unit 220 is a bag formed from an elastic body such as rubber, and holds a fire extinguishing agent therein. The fire extinguishing agent is, for example, potassium carbonate, a strengthened liquid fire extinguishing agent. The shape of the holding unit 220 is not limited to a bag, and the fire extinguishing agent is not limited to a strengthened liquid fire extinguishing agent. The setting unit 222 will be described later. The power supply unit 230 is a battery, and supplies power to the fire alarm 200. Therefore, the power supply unit 230 operates each component of the fire alarm 200, including the communication unit 210.

[0025] The subject of the device, system, or method in the present disclosure includes a computer. The computer executes a program to realize the function of the subject of the device, system, or method in the present disclosure. The computer includes a processor that operates according to a program as a main hardware configuration. The type of the processor does not matter as long as it can realize the function by executing the program. The processor is composed of one or more electronic circuits including a semiconductor integrated circuit (IC) or an LSI (Large Scale Integration). The multiple electronic circuits may be integrated into one chip or may be provided on multiple chips. The multiple chips may be integrated into one device or may be provided on multiple devices. The program is recorded on a non-transitory recording medium such as a computer-readable ROM, an optical disk, or a hard disk drive. The program may be stored in the recording medium in advance, or may be supplied to the recording medium via a wide area communication network including the Internet.

[0026] Figures 3(a)-(c) show the structure of the fire alarm 200. Figure 3(a) is a side view of the fire alarm 200, Figure 3(b) is a perspective view of the fire alarm 200 from below, and Figure 3(c) is a perspective cross-sectional view taken along line A-A' of the fire alarm 200 in Figure 3(b). A cylindrical base 50 is fixed facing downward to the ceiling surface 10. A claw portion (not shown) to which the fire alarm 200 can be attached is provided on the underside of the base 50, and the fire alarm 200 is attached to the underside of the base 50 by fitting the claw portion into a mounting hole 318 in the top surface 300 of the fire alarm 200.

[0027] Fire alarm 200 includes a housing 310 and a front panel 314. Housing 310 has a cylindrical shape with an open bottom, and the bottom is closed by a circular front panel 314. A smoke inlet section 312 is provided in the center of the height direction of housing 310. Smoke inlet section 312 is a through hole that connects the outside and inside of housing 310, and guides smoke from the outside of housing 310 to detection section 214 (FIG. 2) inside.

[0028] The front panel 314 is detachable from the housing 310. The front panel 314 is provided with a front opening 316. The front opening 316 is a through hole that connects the outside and inside of the housing 310, and outputs a buzzer sound generated by the internal alarm unit 216 (FIG. 2) to the outside. Inside the housing 310, the holding unit 220 is disposed below the smoke inlet unit 312. The shape of the housing 310 that holds the extinguishing agent in the holding unit 220 is called a "first shape." The housing 310 houses at least the detection unit 214 and the holding unit 220.

[0029] 4(a)-(b) show an overview of the release of extinguishing agent by the fire alarm 200. FIG. 4(a) shows the state in which the fire alarm 200 is attached to the base 50, i.e., the normal state. This is shown similarly to FIG. 3(a). In the normal state, the fire alarm 200 notifies the user of the occurrence of a fire by sounding a buzzer sound. Upon hearing the buzzer sound, the user recognizes the occurrence of a fire and moves to the location where the fire alarm 200 is installed for initial fire extinguishing.

[0030] FIG. 4(b) shows a state in which the fire alarm 200 is used for initial fire extinguishing, that is, an initial fire extinguishing state. The user removes the fire alarm 200 from the base 50 and throws the fire alarm 200 at the fire scene. When the fire alarm 200 hits the fire scene, the housing 310 or the front panel 314 is deformed inward or damaged. This deformation or damage breaks the holding part 220, and the extinguishing agent is released from inside the holding part 220. In other words, when the housing 310 receives the external impact of deformation or damage, it is transformed from the first shape to a shape that releases the extinguishing agent from the holding part 220 to the outside of the housing 310 (hereinafter referred to as the "second shape").

[0031] The cause of the transformation from the first shape to the second shape is not limited to an external impact. In the following, the mechanisms for transforming the first shape to the second shape will be described in the order of Modification 1 to Modification 4. (Variation 1) 5(a)-(e) show an overview of the release of extinguishing agent by the fire alarm 200. FIG. 5(a) shows the state in which the fire alarm 200 is attached to the base 50, i.e., the normal state. This is shown similarly to FIG. 3(a). In the normal state, the fire alarm 200 notifies the user of the occurrence of a fire by sounding a buzzer sound. Upon hearing the buzzer sound, the user recognizes the occurrence of a fire and moves to the location where the fire alarm 200 is installed for initial fire extinguishing.

[0032] FIG. 5(b) is a cross-sectional view showing a part of the internal structure of the fire alarm 200 in FIG. 5(a). Inside the fire alarm 200, an expandable spring mechanism 320 is disposed between the holding part 220 and the front panel 314. A first connection part 322 and a second connection part 324 are provided on both ends of the spring mechanism 320. The first connection part 322 is connected to the front panel 314, and the second connection part 324 is connected to the holding part 220. In other words, the spring mechanism 320 is connected to the front panel 314 and the holding part 220. It can be said that the housing 310 at this time is in a first shape. Here, the spring mechanism 320, the first connection part 322, and the second connection part 324 may be included in the control part 212.

[0033] Fig. 5(c) shows a state following Fig. 5(b). The user pushes front panel 314 upward with his / her finger. Pushing front panel 314 upward applies an upward external force to spring mechanism 320, causing spring mechanism 320 to contract. Therefore, front panel 314 can also be said to be an operation unit capable of receiving user operations.

[0034] Fig. 5(d) shows a state following Fig. 5(c). When the user releases his / her finger from the state in which the front panel 314 is pushed upward, the spring mechanism 320 stretches due to its elastic force. As the spring mechanism 320 stretches, the front panel 314 moves downward and comes off the first connection portion 322.

[0035] FIG. 5(e) shows a state following FIG. 5(d). As the front panel 314 comes off from the first connecting part 322, the second connecting part 324 also moves downward. As a result, the holding part 220 is pulled downward by the second connecting part 324 and bursts, and the extinguishing agent is ejected from inside the holding part 220. The extinguishing agent is ejected from an opening on the bottom surface of the housing 310. At this time, the housing 310 can be said to be in the second shape. In other words, the spring mechanism 320, the first connecting part 322, and the second connecting part 324 deform the housing 310 from the first shape to the second shape when the front panel 314 accepts an operation.

[0036] (Variation 2) 2, when it detects a fire, notifies control unit 212 of the detection of the fire as described above. When control unit 212 receives the notification from detection unit 214, it transforms housing 310 from the first shape to the second shape.

[0037] 6(a)-(b) show an overview of the release of extinguishing agent by the fire alarm 200. FIG. 6(a) is a cross-sectional view showing a part of the internal structure of the fire alarm 200. Inside the fire alarm 200, particularly the housing 310 (FIG. 3(c)), a support part 330 that supports the holding part 220 from below, and a push rod 332 connected to the underside of the support part 330 are arranged. A motor (not shown) is connected to the push rod 332, and the push rod 332 can be moved up and down by the operation of the motor. The operation of the motor is controlled by the control unit 212 (FIG. 2). It can be said that the housing 310 at this time is in a first shape. Here, the support part 330 and the push rod 332 may be included in the control unit 212.

[0038] FIG. 6(b) shows a state in which the control unit 212, upon receiving a notification from the detection unit 214, operates the motor to move the push rod 332 upward. As the push rod 332 moves upward, the support unit 330 also moves upward. As a result, the holding unit 220 is crushed and bursts inside the housing 310, and the extinguishing agent is ejected from inside the holding unit 220. The extinguishing agent is ejected from the smoke inlet portion 312 of the housing 310 or the front opening 316 of the front panel 314. It can be said that the housing 310 at this time is in the second shape. In other words, the control unit 212 changes the housing 310 from the first shape to the second shape when the detection unit 214 detects a fire.

[0039] The operation of the fire alarm 200 with the above configuration will be described. Fig. 7(a)-(c) are flowcharts showing the transformation procedure by the fire alarm 200. Fig. 7(a) shows the transformation procedure in Modification 2. When the detection unit 214 detects a fire (Y in S10), the notification unit 216 issues a sound (S12). The control unit 212 moves the support unit 330 and the push rod 332 to transform the housing 310 from the first shape to the second shape, causing the extinguishing agent to be ejected from the holding unit 220 (S14). When the detection unit 214 does not detect a fire (N in S10), the process is terminated. Fig. 7(b)-(c) will be described later. When the detection unit 214 detects a fire, the notification unit 216 does not have to issue a sound.

[0040] (Variation 3) As described above, the communication unit 210 in FIG. 2 receives a sounding instruction from the gateway 100. When the communication unit 210 receives the sounding instruction, the control unit 212 causes the notification unit 216 to sound a buzzer sound. When the communication unit 210 receives the sounding instruction, the control unit 212 also causes the housing 310 to deform from the first shape to the second shape. The housing 310 is deformed as shown in FIG. 6(a)-(b). As a result, the extinguishing agent is sprayed from the smoke inlet portion 312 of the housing 310 or the front opening 316 of the front panel 314.

[0041] Fig. 7(b) shows a modification procedure in Modification 3. When the communication unit 210 receives an instruction to sound from the gateway 100 (Y in S20), the alarm unit 216 executes sounding (S22). The control unit 212 moves the support unit 330 and the push rod 332 to deform the housing 310 from the first shape to the second shape, causing the extinguishing agent to be ejected from the holding unit 220 (S24). When the detection unit 214 does not detect a fire (N in S20), the process ends. Fig. 7(c) will be described later.

[0042] (Variation 4) It may be set in advance whether or not the control unit 212 transforms the housing 310 from the first shape to the second shape when the communication unit 210 receives a ringing instruction from the gateway 100. The setting unit 222 in Fig. 2 sets, as the operation of the control unit 212, whether the transformation is performed when a ringing instruction is received (hereinafter referred to as "on"), or whether the transformation is not performed when a ringing instruction is received (hereinafter referred to as "off").

[0043] As described above, the communication unit 210 in FIG. 2 receives a sounding instruction from the gateway 100. When the communication unit 210 receives a sounding instruction, the control unit 212 causes the notification unit 216 to sound a buzzer sound. When the communication unit 210 receives a sounding instruction, if the setting unit 222 is set to ON, the control unit 212 causes the housing 310 to deform from the first shape to the second shape. The housing 310 is deformed as shown in FIG. 6(a)-(b). As a result, the extinguishing agent is sprayed from the smoke inlet portion 312 of the housing 310 or the front opening 316 of the front panel 314. On the other hand, when the communication unit 210 receives a sounding instruction, if the setting unit 222 is set to OFF, the control unit 212 does not cause the housing 310 to deform from the first shape to the second shape.

[0044] 7(c) shows a modification procedure in Modification 4. When the communication unit 210 receives an instruction to sound from the gateway 100 (Y in S30), the alarm unit 216 executes sounding (S32). When it is set to on (Y in S34), the control unit 212 moves the support unit 330 and the push rod 332 to deform the housing 310 from the first shape to the second shape, and causes the extinguishing agent to be ejected from the holding unit 220 (S36). When it is not set to on (N in S34), step 36 is skipped. When the communication unit 210 does not receive an instruction to sound from the gateway 100 (N in S30), the process is terminated.

[0045] According to this embodiment, the holding part 220 holds the extinguishing agent, and the housing 310 can be deformed between a first shape in which the extinguishing agent is held in the holding part 220 and a second shape in which the extinguishing agent is released from the holding part 220 to the outside of the housing 310, so that initial extinguishing can be performed. In addition, since the fire alarm 200 has a function of extinguishing a fire, initial extinguishing can be performed. In addition, since the housing 310 contains the holding part 220 of the extinguishing agent, the extinguishing agent cannot be seen from the outside of the housing 310, and the design can be improved. In addition, since the housing 310 is removable from the installation location and the housing 310 is deformed by receiving an external impact, initial extinguishing can be performed by throwing the fire alarm 200 toward the source of the fire.

[0046] Furthermore, when a fire is detected, the housing 310 is transformed from the first shape to the second shape, so that the extinguishing agent can be automatically released in conjunction with the detection of a fire. Furthermore, since the extinguishing agent is automatically released in conjunction with the detection of a fire, initial fire extinguishing can be performed quickly. Furthermore, since the housing 310 is transformed by the user's operation, usability can be improved. Furthermore, since the extinguishing agent is released in response to the reception of an instruction to sound, usability can be improved. Furthermore, since the extinguishing agent is released in response to the reception of an instruction to sound, initial fire extinguishing can be performed quickly. Furthermore, since it is set whether or not to release the extinguishing agent in response to the reception of an instruction to sound, an operation according to the user's intention can be performed.

[0047] An overview of one aspect of the present disclosure may be summarized as follows. (Item 1) A detection unit (214) for detecting a fire; A holding portion (220) for holding a fire extinguishing agent; a housing (310) that houses the detection unit (214) and the holding unit (220); The fire alarm (200) is capable of transforming between a first shape in which the extinguishing agent is held in the holding portion (220) and a second shape in which the extinguishing agent is released from the holding portion (220) to the outside of the housing (310).

[0048] (Item 2) The housing (310) is removable from the installation site; 2. The fire alarm (200) according to item 1, wherein the housing (310) is deformed from the first shape to the second shape by receiving an external impact.

[0049] (Item 3) 2. The fire alarm (200) according to item 1, further comprising a control unit (212) that, when the detection unit (214) detects the fire, causes the housing (310) to deform from the first shape to the second shape.

[0050] (Item 4) an operation unit (314) capable of receiving user operations; 2. The fire alarm (200) according to item 1, further comprising a control unit (212) that, when the operation unit (314) accepts the operation, transforms the housing (310) from the first shape to the second shape.

[0051] (Item 5) A communication unit (210) capable of communicating with an external device (100); 2. The fire alarm (200) according to item 1, further comprising a control unit (212) that transforms the housing (310) from the first shape to the second shape when the communication unit (210) receives a signal from the external device (100).

[0052] (Item 6) A setting unit (222) that sets the operation of the control unit (212), When the setting unit (222) sets the ON state, the control unit (212) changes the shape of the housing (310) from the first shape to the second shape when the communication unit (210) receives a signal from the external device (100), 6. The fire alarm (200) according to claim 5, wherein when the setting unit (222) sets off, the control unit (212) does not transform the housing (310) from the first shape to the second shape even if the communication unit (210) receives a signal from the external device (100).

[0053] The present disclosure has been described above based on the embodiments. These embodiments are merely illustrative, and it will be understood by those skilled in the art that various modifications are possible in the combination of each component or each treatment process, and that such modifications are also within the scope of the present disclosure. [Explanation of symbols]

[0054] 10 ceiling surface, 50 base, 100 gateway, 200 fire alarm, 210 communication unit, 212 control unit, 214 detection unit, 216 notification unit, 220 holding unit, 222 setting unit, 230 power supply unit, 300 top surface, 310 housing, 312 smoke inlet unit, 314 front panel, 316 front opening, 318 mounting hole, 320 spring mechanism, 322 first connection unit, 324 second connection unit, 330 support unit, 332 push rod, 1000 alarm system.

Claims

1. A detection unit that detects a fire; A holding portion for holding a fire extinguishing agent; a housing that houses the detection unit and the holding unit, A fire alarm in which the housing is deformable between a first shape in which the extinguishing agent is held in the holding portion and a second shape in which the extinguishing agent is released from the holding portion to the outside of the housing.

2. The housing is removable from the installation location; The fire alarm according to claim 1 , wherein the housing is deformed from the first shape to the second shape by receiving an external impact.

3. The fire alarm according to claim 1 , further comprising a control unit that, when the detection unit detects the fire, deforms the housing from the first shape to the second shape.

4. An operation unit capable of accepting user operations; The fire alarm according to claim 1 , further comprising a control unit that, when the operation unit receives the operation, transforms the housing from the first shape to the second shape.

5. A communication unit capable of communicating with an external device; The fire alarm according to claim 1 , further comprising a control unit that, when the communication unit receives a signal from the external device, transforms the housing from the first shape to the second shape.

6. A setting unit that sets the operation of the control unit is further provided. When the setting unit sets the ON state, the control unit transforms the housing from the first shape to the second shape when the communication unit receives a signal from the external device; The fire alarm of claim 5 , wherein when the setting unit sets off, the control unit does not transform the housing from the first shape to the second shape even if the communication unit receives a signal from the external device.

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