Alarm device

Abstract

To provide an alarm device capable of improving safety.SOLUTION: An alarm device comprises: an alarm device main body having notification means for issuing an alarm; a switch which is installed inside the alarm device main body and which stops the alarm when operated while the alarm is sounding; a pull string connected to the switch and pulled out from the alarm device main body; and a position changing unit that moves an outer end portion of the pull string, which is located outside the alarm device main body, so as to approach the alarm device main body or a ceiling when it reaches a high temperature equal to or higher than a predetermined temperature.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an alarm device.

Background Art

[0002] Conventionally, there is a fire alarm device having a pull cord drawn out from the inside of the alarm device main body to the outside, and it is possible to stop the alarm sound by pulling the pull cord (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When an alarm is sounding during a fire, the user may hurriedly pull the pull cord to stop the alarm sound. If the alarm sound is stopped in this way, it becomes impossible to notify the surrounding area of the occurrence of the fire. In the fire alarm device of Patent Document 1, no consideration has been given to this point, and there is a problem in safety.

[0005] Therefore, an object of the present invention is to obtain an alarm device capable of enhancing safety.

Means for Solving the Problems

[0006] The alarm device of the present invention includes an alarm device main body provided with notification means for issuing an alarm, a switch provided inside the alarm device main body and operated during alarm sound to stop the alarm, a pull cord connected to the switch and drawn out to the outside of the alarm device main body, and a position changing unit that, when the temperature reaches a predetermined temperature or higher, moves the outer end portion of the pull cord located outside the alarm device main body closer to the alarm device main body or the ceiling.

Effects of the Invention

[0007] When the temperature of the alarm device according to the present invention reaches a high temperature equal to or higher than a predetermined temperature, the outer end portion of the pull cord moves so as to approach the alarm device main body or the ceiling, and moves to a position that is difficult to operate by the user. Therefore, incorrect operations can be suppressed and safety can be enhanced.

Brief Description of the Drawings

[0008]

Figure 1

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Embodiments for Carrying Out the Invention

[0009] Embodiment 1. Figure 1 is an external view of the fire alarm 100 according to Embodiment 1. The fire alarm 100 is an example of an alarm, and includes an alarm main body 10 fixed to a wall surface such as a ceiling, and a pull cord 20. Hereinafter, the circuit configuration inside the alarm main body 10 will be described, and then the pull cord 20 will be described.

[0010] Figure 2 is a diagram for showing the circuit configuration and the like of the fire alarm 100 according to Embodiment 1. The alarm main body 10 includes a control circuit 1, a battery 2, a power supply circuit 3, a battery voltage detection circuit 4, a transmission / reception circuit 5, an antenna 6, a fire detection circuit 7, an alarm sound control circuit 8, a display circuit 9, and an inspection / alarm stop switch 11.

[0011] The control circuit 1 controls the entire fire alarm 100. The control circuit 1 performs processing based on input signals and the like, and controls circuits and the like included in the fire alarm 100. For example, when a signal related to fire detection from the fire detection circuit 7 described later is input, the control circuit 1 operates the alarm sound control circuit 8 and the display circuit 9 to perform control such as sounding an alarm related to the fire by sound and display. The control circuit 1 performs communication processing with devices such as other fire alarms 100 via the transmission / reception circuit 5. The control circuit 1 is configured by, for example, a microprocessor unit or the like.

[0012] The battery 2 supplies a DC power supply to the power supply circuit 3. The power supply circuit 3 controls the voltage of the battery 2 to a predetermined voltage and supplies it to each circuit of the fire alarm 100. The battery voltage detection circuit 4 detects the voltage related to the application of the battery 2 and outputs a battery voltage detection signal corresponding to the detected voltage to the control circuit 1. The control circuit 1 drives the alarm sound control circuit 8 and the display circuit 9 based on the battery voltage detection signal from the battery voltage detection circuit 4 to notify battery exhaustion and the like.

[0013] The transmission / reception circuit 5 transmits and receives various signals to and from the transmission / reception circuits of other devices such as other fire alarms. When a fire is detected, the fire alarm 100 transmits an interlock control signal from the transmission / reception circuit 5 to other devices and sounds an alarm in conjunction with the other devices. Note that the fire alarm 100 is not limited to a configuration including the transmission / reception circuit 5. The fire alarm 100 may not include the transmission / reception circuit 5 and the antenna 6 and may sound an alarm independently.

[0014] The fire detection circuit 7 detects physical changes such as smoke and heat based on the fire phenomenon and outputs a signal corresponding to the detection content to the control circuit 1. Here, the fire detection circuit 7 compares the smoke density with a preset fire detection threshold value, determines that a fire has been detected when the smoke density is equal to or higher than the fire detection threshold value, and outputs a signal related to the fire detection to the control circuit 1 for explanation purposes.

[0015] The alarm sound control circuit 8 is a circuit that controls the operation of generating an alarm sound or the like from a buzzer, speaker, etc. (not shown). The display circuit 9 is a circuit that controls the lighting operation of a display lamp (not shown) such as a light-emitting diode. Here, it is described that the display circuit 9 is a circuit that controls the lighting of the display lamp, but when the fire alarm 100 has display means capable of displaying, for example, characters, numbers, etc., the display circuit 9 may control the display of characters and the like. One or both of the alarm sound control circuit 8 and the display circuit 9 serve as notification means for issuing an alarm. Here, the notification means is composed of both the alarm sound control circuit 8 and the display circuit 9. When a fire is detected by the fire detection circuit 7, for example, the alarm sound control circuit 8 generates a voice such as "Peep, Hoo, Hoo, There is a fire, There is a fire" and operates the display circuit 9 to blink the display lamp, for example, in red.

[0016] The inspection / alarm stop switch 11 is a switch for stopping the alarm when operated by the user during alarm sounding. Also, the inspection / alarm stop switch 11 is a switch that is operated when inspecting whether the alarm sounds, and when operated by the user during alarm stop, it is a switch for sounding the alarm. The inspection / alarm stop switch 11 is, for example, a button-type switch or a dip switch or the like.

[0017] The control circuit 1 performs control based on the operation of the inspection / alarm stop switch 11. Specifically, when the inspection / alarm stop switch 11 is operated during alarm sounding, the control circuit 1 controls the alarm sound control circuit 8 and the display circuit 9 to stop the alarm sounding. Also, when the inspection / alarm stop switch 11 is operated during alarm stop, the control circuit 1 controls the alarm sound control circuit 8 and the display circuit 9 to sound the alarm.

[0018] A pull cord 20 is connected to the inspection / alarm stop switch 11. The pull cord 20 is a long member for operating the inspection / alarm stop switch 11 from outside the alarm device main body 10. The pull cord 20 is provided so that the user can easily operate the inspection / alarm stop switch 11 even when the fire alarm 100 is fixed in a place difficult to reach such as the ceiling. The inner end portion of the pull cord 20 is connected to the inspection / alarm stop switch 11, and the outer end portion 20a is drawn out to the outside of the alarm device main body 10.

[0019] By the way, when a fire occurs and the alarm is sounding, the user may hurriedly pull the pull cord 20 to stop the alarm sounding.

[0020] The fire alarm 100 of Embodiment 1 includes a position changing portion 30 that moves the position of the outer end portion 20a of the pull cord 20 closer to the alarm device main body 10 or the ceiling than the position before the fire occurs, so as to suppress the user from hurriedly pulling the pull cord 20 when a fire occurs.

[0021] In Embodiment 1, the pull cord 20 of the fire alarm 100 also serves as the position changing part 30 by having the following configuration. The pull cord 20 is made of a shape memory alloy that deforms due to temperature changes, and the pull cord 20 itself functions as the position changing part 30. The pull cord 20 may be composed only of a cord made of a shape memory alloy, or may be composed of a combination of a cord made of a shape memory alloy and a cord. made of thread, leather, etc. It may be composed of a combination of a cord and a cord.

[0022] During normal times when a fire has not occurred, the temperature of the pull cord 20 is less than a predetermined temperature. In this case, the pull cord 20 is in an extended state as shown in FIG. 1, and the outer end portion 20a of the pull cord 20 is in a position that is easily touched by the user.

[0023] Here, when a fire occurs and the temperature around the alarm body 10 rises and the temperature of the pull cord 20 becomes a high temperature of a predetermined temperature or more, the pull cord 20 deforms as shown in FIG. 3 below.

[0024] FIG. 3 is an external view of the fire alarm 100 according to Embodiment 1 at high temperature. The pull cord 20 deforms so as to bend at high temperature as shown in FIG. 3. When the pull cord 20 bends, the outer end portion 20a of the pull cord 20 moves closer to the alarm body 10, in other words, moves to the ceiling side where it is difficult for the user to operate. Note that the deformation of the pull cord 20 is not limited to the illustrated example. When the pull cord 20 is composed of, for example, a coil-shaped shape memory alloy, it may be deformed into a contracted state at high temperature.

[0025] As described above, in the fire alarm 100 of Embodiment 1, since the outer end portion 20a of the pull cord 20 moves to a position where it is difficult for the user to operate at high temperature, it is possible to prevent the user from accidentally pulling the pull cord 20 in a hurry during the alarm sound when a fire occurs and stopping the alarm sound.

[0026] Note that, under normal circumstances, as described above, the pull cord 20 is in the extended state shown in FIG. 1 and is in a position where it is easy for the user to pull. Therefore, during inspection, the user can easily pull the pull cord 20, and the fire alarm 100 can maintain the convenience provided by the pull cord 20.

[0027] Embodiment 2. In Embodiment 2, the configurations of the pull cord 20 and the position changing unit 30 are different from those in Embodiment 1. Hereinafter, the description will focus on the configurations in which Embodiment 2 differs from Embodiment 1, and the configurations not described in Embodiment 2 are the same as those in Embodiment 1.

[0028] FIG. 4 is an external view of the fire alarm 100 according to Embodiment 2 under normal circumstances. FIG. 5 is an external view of the fire alarm 100 according to Embodiment 2 at high temperature. FIG. 6 is a schematic side view of the position changing unit 30A in the fire alarm 100 according to Embodiment 2 under normal circumstances. FIG. 7 is a schematic side view of the position changing unit 30A in the fire alarm 100 according to Embodiment 2 at high temperature.

[0029] As shown in FIGS. 4 and 5, the fire alarm 100 of Embodiment 2 includes an alarm body 10 and a pull cord 21. In Embodiment 1 described above, the pull cord 20 was made of a shape memory alloy, but the pull cord 21 of Embodiment 2 is composed of a cord made of a thread or the like.

[0030] As shown in FIGS. 6 and 7, the position changing unit 30A of Embodiment 2 includes a heat receiving part 31, a spring 32, and a winding mechanism 33. The heat receiving part 31 is, for example, a rod-shaped member made of a metal member, and is installed on the alarm body 10 such that one end protrudes outside the alarm body 10. Since one end of the heat receiving part 31 protrudes outside the alarm body 10, it is easy to receive the heat outside the alarm body 10.

[0031] The spring 32 is composed of a coiled shape memory alloy that expands and contracts by heat. The spring 32 is arranged in contact with the heat receiving part 31 and expands and contracts due to the heat of the heat receiving part 31. The spring 32 has a switch pressing part 32a that interlocks with the expansion and contraction operation of the spring 32. The switch pressing part 32a is a part that mechanically presses a drive switch 33b that drives a motor 33a of a winding mechanism 33 described later.

[0032] The winding mechanism 33 is a mechanism that winds a pull cord 21 drawn out to the outside of the alarm device main body 10 into the alarm device main body 10. The winding mechanism 33 has a motor 33a that winds the pull cord 21 into the alarm device main body 10. Although not shown in detail in FIG. 6, the inner end portion of the pull cord 21 is connected to an inspection / alarm stop switch 11, and the winding mechanism 33 winds an intermediate portion from the inner end portion of the pull cord 21 until it is drawn out to the outside of the alarm device main body 10. And as shown in FIG. 6, the inspection / alarm stop switch 11 is operated when the pull cord 21 is further pulled from the extended state.

[0033] In the fire alarm 100 having the above configuration, normally, as shown in FIG. 6, the pull cord 21 is in a state of being long drawn out to the outside of the alarm device main body 10, and the outer end portion 21a of the pull cord 21 is at a position away from the alarm device main body 10 and easy to operate by the user. Also, normally, the spring 32 is in an extended state, and the switch pressing part 32a is at a position away from the drive switch 33b.

[0034] When a fire occurs and the temperature around the alarm device main body 10 rises, and the heat of the heat receiving part 31 is transmitted to the spring 32 and the spring 32 reaches a high temperature of a predetermined temperature or higher, the spring 32 becomes in a contracted state as shown in FIG. 7. When the spring 32 is in a contracted state, the switch pressing part 32a that interlocks with the expansion and contraction of the spring 32 presses the drive switch 33b. As a result, the motor 33a of the winding mechanism 33 is driven, and the pull cord 21 is wound into the alarm device main body 10. As a result, as shown in FIG. 7, the outer end portion 21a of the pull cord 21 moves closer to the alarm device main body 10, in other words, moves to the ceiling side where it is difficult to operate by use.

[0035] As described above, the fire alarm 100 of the second embodiment has a spring 32 made of a shape memory alloy whose telescopic change is caused by a temperature change in the position changing part 30A. When the temperature is high, the spring 32 contracts, driving the motor 33a, and the outer end 21a of the pulling cord 21 moves to a position that is difficult for the user to operate. Thus, similar to the first embodiment, the fire alarm 100 of the second embodiment can prevent the user from accidentally pulling the pulling cord 21 in a hurry during the alarm sound when a fire occurs, thereby stopping the alarm sound.

[0036] Here, an example in which the motor 33a is driven by the contraction of the spring 32 due to high temperature has been described. However, a configuration in which the motor 33a is driven by the expansion of the spring 32 due to high temperature may also be used. That is, the motor 33a only needs to be configured to be driven by the telescopic change of the spring 32.

[0037] Embodiment 3. In the third embodiment, the configuration of the position changing part is different from that of the second embodiment. Hereinafter, the description will focus on the configuration in which the third embodiment differs from the second embodiment, and the configurations not described in the third embodiment are the same as those in the second embodiment.

[0038] FIG. 8 is a schematic side view of the position changing part 30B of the fire alarm 100 according to the third embodiment in the normal state. FIG. 9 is a schematic side view of the position changing part 30B of the fire alarm 100 according to the third embodiment at high temperature.

[0039] The position changing part 30B of the third embodiment has a different configuration for driving the winding mechanism 33 from that of the position changing part 30A of the second embodiment. The position changing part 30B has a temperature sensor 34 that detects the temperature due to the heat of the heat receiving part 31, and the winding mechanism 33 is driven based on the detected temperature of the temperature sensor 34. As a specific control, when the temperature detected by the temperature sensor 34 becomes a high temperature equal to or higher than a predetermined temperature, the control circuit 1 (see FIG. 2) drives the motor 33a.

[0040] In the fire alarm 100 with the above configuration, normally, as shown in FIG. 8, the pull cord 21 is in a state of being long drawn out outside the alarm main body 10, and the outer end portion 21a of the pull cord 21 is at a position away from the alarm main body 10 and easy for the user to operate.

[0041] When a fire occurs and the temperature around the alarm main body 10 rises, the detected temperature of the temperature sensor 34 becomes equal to or higher than a predetermined temperature due to the heat of the heat receiving portion 31. When the detected temperature of the temperature sensor 34 becomes equal to or higher than the predetermined temperature, the motor 33a is driven under the control of the control circuit 1, and as shown in FIG. 9, the pull cord 21 is wound into the alarm main body 10. As a result, the outer end portion 21a of the pull cord 21 moves closer to the alarm main body 10, in other words, it moves to the ceiling side where it is difficult for the user to operate.

[0042] As described above, in the fire alarm 100 of Embodiment 3, the configuration of the position changing unit 30B includes the temperature sensor 34, and when the temperature sensor 34 detects a high temperature equal to or higher than a predetermined temperature, the motor 33a is driven and the outer end portion 21a of the pull cord 21 moves to a position where it is difficult for the user to operate. Thus, similar to Embodiment 2, the fire alarm 100 of Embodiment 3 can suppress the user from accidentally pulling the pull cord 21 in a hurry during the alarm sound when a fire occurs and stopping the alarm sound.

[0043] Embodiment 4. In Embodiment 4, the configuration of the position changing unit is different from that of Embodiment 2. Hereinafter, the description will focus on the configuration in which Embodiment 4 is different from Embodiment 2, and the configurations not described in Embodiment 4 are the same as those in Embodiment 2.

[0044] FIG. 10 is a schematic diagram of the position changing unit 30C in the fire alarm 100 according to Embodiment 4 in the normal state. FIG. 11 is a schematic diagram of the position changing unit 30C in the fire alarm 100 according to Embodiment 4 at a high temperature.

[0045] The position changing part 30C of the fourth embodiment includes a heat receiving part 31 similar to that of the second embodiment and a spring 35. The spring 35 is arranged inside the alarm device main body 10 and is a coil-shaped spring made of a shape memory alloy that expands and contracts due to temperature changes. One end of the spring 35 is connected to the heat receiving part 31, and the other end of the spring 35 is connected to a part located inside the alarm device main body 10 in the pull cord 21, although not shown in detail.

[0046] In the above configuration, as shown in FIG. 10, normally, the spring 35 is extended and the pull cord 21 is in a state of being pulled out long outside the alarm device main body 10. When a fire occurs and the temperature around the alarm device main body 10 rises, and the heat of the heat receiving part 31 is transmitted to the spring 35 and the spring 35 reaches a high temperature of a predetermined temperature or higher, the spring 35 becomes in a contracted state as shown in FIG. 11. When the spring 35 is in a contracted state, the pull cord 21 is pulled into the alarm device main body 10. As a result, the outer end portion 21a of the pull cord 21 moves closer to the alarm device main body 10, in other words, it moves to the ceiling side where it is difficult for the user to reach.

[0047] As described above, the fire alarm 100 of the fourth embodiment has a spring 35 made of a shape memory alloy whose expansion and contraction change due to temperature change in the position changing part 30C, and when the temperature is high, the spring 35 contracts, so that the outer end portion 21a of the pull cord 21 moves to the ceiling side where it is difficult for the user to reach. Thereby, similar to the second embodiment, the fire alarm 100 of the fourth embodiment can suppress the user from accidentally pulling the pull cord 21 in a hurry during the alarm sound when a fire occurs and stopping the alarm sound.

[0048] Embodiment 5. In the above-described Embodiments 1 to 4, when a fire occurs (at high temperature), the fire alarm 100 moves the outer ends 20a, 21a of the pull cords 20, 21 (hereinafter, the reference numeral 20 is used to represent the pull cords) to a position that is difficult for the user to pull, thereby suppressing the situation where the pull cord 20 is hurriedly pulled and the alarm stops sounding. However, when the pull cord 20 is actually pulled, the fire alarm 100 stops the alarm from sounding. The fire alarm 100 of Embodiment 5 is configured such that even when the pull cord 20 is pulled, the alarm does not stop sounding when the following first condition is satisfied. The configuration of the fire alarm 100 is the same as that in Embodiments 1 to 4. Hereinafter, the description will focus on the operations in which Embodiment 5 differs from Embodiments 1 to 4.

[0049] FIG. 12 is a diagram showing a flowchart of the alarm process related to a fire of the fire alarm 100 according to Embodiment 5. Here, it is assumed that the smoke density is equal to or higher than the fire detection threshold and the alarm is sounding, and the outer end 20a of the pull cord 20 is in a position that is difficult for the user to pull. When the control circuit 1 detects that the pull cord 20 has been pulled and the inspection / alarm stop switch 11 has been operated (S21), it determines whether the first condition is satisfied. The first condition is that the smoke density is equal to or higher than a first threshold that exceeds the fire detection threshold. Therefore, specifically, the control circuit 1 determines whether the smoke density is equal to or higher than the first threshold that exceeds the fire detection threshold (S22).

[0050] When the smoke density is not equal to or higher than the first threshold, that is, when the smoke density is equal to or higher than the fire detection threshold and less than the first threshold, the control circuit 1 controls the alarm sound control circuit 8 and the display circuit 9 to stop the alarm from sounding, in the same manner as in Embodiments 1 to 4 (S23). Thereby, for example, when the alarm sounds in a state where it is known that there is no fire, such as during cooking, it is possible to avoid the continuous sounding of the alarm and improve convenience.

[0051] On the other hand, when the control circuit 1 determines in step S22 that the smoke density is equal to or higher than the first threshold value, that is, when the first condition is satisfied, the control circuit 1 continues the alarm sound (S24). As specific control, the control circuit 1 does not transmit a signal to stop the alarm sound to the alarm sound control circuit 8 and the display circuit 9. The case where the first condition is satisfied can be said to be the case where it is necessary to widely notify the surrounding area of a fire. When the first condition is satisfied, the fire alarm 100 continues the alarm sound without stopping even if the pull cord 20 is pulled, so that the safety can be improved.

[0052] Note that the above function of not stopping the alarm sound even when the pull cord 20 is pulled is not limited to being applied to the fire alarm 100 of the present invention, and may be applied to existing fire alarms. That is, the above function may be applied to a fire alarm that does not have a configuration in which the position of the outer end portion 20a of the pull cord 20 changes depending on the temperature.

[0053] Also, in all of the above embodiments, an example of the fire alarm 100 that detects a physical change in smoke based on a fire phenomenon has been described. However, a fire alarm that detects a physical change based on other fire phenomena such as heat (temperature) or flame (infrared ray) may be used. In that case, in Embodiment 5, for example, the fire alarm 100 includes a fire detection circuit that detects a fire when a physical quantity level such as a temperature level or an infrared ray level is equal to or higher than a fire detection threshold value, and the first condition is that the physical quantity level such as the temperature level or the infrared ray level is equal to or higher than a first threshold value that exceeds the fire detection threshold value at which a fire is detected in the fire detection circuit.

[0054] Note that in all of the above embodiments, an example of the fire alarm 100 that detects a fire has been described. However, the alarm may be an alarm that detects an abnormality in another environment such as a gas leak.

Explanation of Reference Numerals

[0055] 1 Control circuit, 2 Battery, 3 Power supply circuit, 4 Battery voltage detection circuit, 5 Transceiver circuit, 6 Antenna, 7 Fire detection circuit, 8 Alarm sound control circuit, 9 Display circuit, 10 Alarm device main body, 11 Inspection / alarm stop switch, 20 Pull cord, 20a Outer end portion, 21 Pull cord, 21a Outer end portion, 30 Position changing portion, 30A Position changing portion, 30B Position changing portion, 30C Position changing portion, 31 Heat receiving portion, 32 Spring, 32a Switch pressing portion, 33 Rewinding mechanism, 33a Motor, 33b Drive switch, 34 Temperature sensor, 35 Spring, 100 Fire alarm.

Claims

1. An alarm device main body provided with a notification means for issuing an alarm, A switch provided inside the alarm device main body and operated during alarm sounding to stop the alarm, A pull cord connected to the switch and drawn out to the outside of the alarm device main body, A position changing unit that, when the temperature reaches a predetermined temperature or higher, moves the outer end of the pull cord located outside the alarm device main body closer to the alarm device main body or the ceiling. The alarm device is provided with: Alarm device.

2. The pull cord also serves as the position changing unit and is a long member made of a shape memory alloy that deforms due to temperature changes. When the temperature reaches a predetermined temperature or higher, it bends. The alarm device according to claim 1.

3. The position changing unit is: A spring disposed inside the alarm device main body and made of a shape memory alloy that expands and contracts due to temperature changes, A motor that is driven by the expansion and contraction of the spring when the temperature reaches a predetermined temperature or higher and winds the pull cord into the inside of the alarm device main body. The alarm device according to claim 1.

4. The position changing unit is: A temperature sensor for detecting temperature, A motor that is driven when the temperature detected by the temperature sensor reaches a predetermined temperature or higher and winds the pull cord into the inside of the alarm device main body. The alarm device according to claim 1.

5. The position changing unit is: It has a spring made of a shape memory alloy that expands and contracts due to temperature changes and retracts the pull cord into the inside of the alarm device main body by contracting at a high temperature of a predetermined temperature or higher. The alarm device according to claim 1.

6. It is provided with a control circuit for controlling the notification means, The control circuit controls the notification means so as not to stop the alarm sound when the switch is operated during alarm sounding and a first condition is satisfied. The alarm device according to any one of claims 1 to 5.

7. It is provided with a fire detection circuit that detects a fire when the smoke concentration is equal to or higher than a fire detection threshold value, The first condition is that the smoke concentration is equal to or higher than a first threshold value exceeding the fire detection threshold value at which a fire is detected in the fire detection circuit. The alarm device according to claim 6.

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