Fire-fighting detector and fire-fighting detection system

Abstract

The utility model provides a fire-fighting detector and a fire-fighting detection system. The fire-fighting detector comprises a voltage monitoring module used for monitoring the voltage of a loop where the fire-fighting detector is located; the current adjusting module is used for adjusting the current of a loop where the fire-fighting detector is located; one end of the control module is connected with a voltage source, the other end of the control module is grounded, and the control module is connected with the voltage monitoring module and the current adjusting module and used for controlling the voltage monitoring module to monitor the loop voltage and controlling the current adjusting module to adjust the loop current based on the loop voltage. According to the fire-fighting detector, the loop current can be adjusted, so that the loop current can be kept balanced, the fire-fighting detector operates stably, the robustness and reliability of the fire-fighting detector are improved, important guarantee is provided for fire-fighting safety, the fire-fighting detector can adapt to different control panels, and the universality of the fire-fighting detector is improved.

Description

Technical Field

[0001] The present disclosure generally relates to the field of fire protection, and more particularly to a fire detector and a fire detection system. Background Art

[0002] In the current field of fire protection, the number of fire detectors that alarm in a loop is limited, and impedance matching between the detector and the control panel is required, which limits the reliability and versatility of the fire detector. Therefore, how to make the fire detector adapt to different control panels and achieve multiple fire detectors alarm in a loop, so that the fire detector operates stably, is a technical problem that needs to be solved urgently in this field.

[0003] The content of the background art section is only the technology known to the inventor and does not necessarily represent the prior art in this field. Summary of the Utility Model

[0004] In view of one or more of the problems existing in the prior art, the present disclosure provides a fire detector, including:

[0005] A voltage monitoring module for monitoring the loop voltage where the fire detector is located;

[0006] A current regulation module for regulating the loop current where the fire detector is located; and

[0007] A control module, one end connected to a voltage source and the other end grounded, and the control module is also connected to the voltage monitoring module and the current regulation module, for controlling the voltage monitoring module to monitor the loop voltage and controlling the current regulation module to regulate the loop current based on the loop voltage.

[0008] Optionally, the control module includes a first resistor and a second resistor connected in series, the first resistor is connected to the voltage source, the second resistor is grounded, the voltage monitoring module includes an AD converter, and the AD converter is connected between the output end of the first resistor and the input end of the second resistor and collects the voltage at the output end.

[0009] Optionally, the control module determines the loop voltage based on the voltage at the output end, and the loop voltage satisfies:

[0010]

[0011] where V is the loop voltage, V AD is the voltage at the output end, Vref is the reference voltage, R 1 is the resistance value of the first resistor, R 2 is the resistance value of the second resistor.

[0012] Optionally, the control module determines the change amount of the loop voltage, and based on the change amount, controls the current regulation module to regulate the loop current.

[0013] Optionally, when the change amount is greater than a first threshold, the control module controls the current regulation module to reduce the loop current.

[0014] Optionally, the current regulation module includes a first switch and a third resistor. The first switch is connected to the voltage source. One end of the third resistor is connected to the first switch, and the other end is grounded. The control module controls the first switch and / or the third resistor to regulate the loop current.

[0015] Optionally, the third resistor is a variable resistor. The control module controls the first switch to conduct and regulates the resistance value of the third resistor to regulate the loop current.

[0016] Optionally, the first switch includes a metal oxide semiconductor field effect transistor. Its drain is connected to the voltage source, its source is connected to the third resistor, and its gate is connected to the control module. The control module controls the first switch to conduct and regulates its gate voltage to regulate the loop current.

[0017] Optionally, there are multiple third resistors, and the multiple third resistors are connected in parallel. The current regulation module further includes: multiple second switches, and the second switches are connected in series with the third resistors. The control module controls the first switch to conduct and controls the on / off of the second switches to regulate the loop current.

[0018] Optionally, the current regulation module further includes a fourth resistor. The fourth resistor is connected to the voltage source and the first switch. The control module regulates the fourth resistor to regulate the loop current.

[0019] Optionally, it further includes: an upper cover, a circuit board, and a rear cover, where the circuit board is located between the upper cover and the rear cover, and the voltage monitoring module, the current regulation module, and the control module are integrated on the circuit board.

[0020] Optionally, it further includes: a base, and the rear cover covers the base to isolate and support the circuit board.

[0021] Optionally, the fire detector includes a smoke detector, and the smoke detector includes: a maze cover, a smoke maze, and a shielding cover, and the maze cover, the smoke maze, and the shielding cover are located between the upper cover and the circuit board.

[0022] Optionally, it further includes: an infrared emitting tube, an infrared receiving tube, and a temperature sensor respectively coupled to the control module, for sensing smoke or temperature to assist in determining whether the fire detector alarms.

[0023] Optionally, it further includes: a display module and / or a voice module, for displaying and / or announcing whether the fire detector alarms.

[0024] Optionally, the fire detector is a non-addressable fire detector.

[0025] The present disclosure also provides a fire detection system, including:

[0026] A control panel; and

[0027] A plurality of the above-mentioned fire detectors, and the plurality of fire detectors are connected in parallel to the control panel, wherein:

[0028] The fire detector monitors the loop voltage where it is located through a voltage monitoring module, and the control panel determines whether the fire detector alarms based on the loop voltage.

[0029] Optionally, the control panel determines that the fire detector alarms when the change amount of the loop voltage is greater than a first threshold.

[0030] Optionally, when the loop voltage of the fire detector is lower than a second threshold, the loop current is reduced through a current adjustment module.

[0031] The fire detector of the present disclosure can adjust the loop current, so that the loop current can be kept balanced, enabling the fire detector to operate stably, improving the robustness and reliability of the fire detector, providing an important guarantee for fire safety, and can be adapted to different control panels, improving the versatility of the fire detector. Description of the Drawings

[0032] The drawings are used to provide a further understanding of the present disclosure, and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the present disclosure, and do not constitute a limitation to the present disclosure. In the drawings:

[0033] Figure 1 A circuit schematic diagram of a fire detector according to some embodiments of the present disclosure is shown.

[0034] Figure 2 A partial circuit schematic diagram of a fire detector according to some embodiments of the present disclosure is shown.

[0035] Figure 3 A partial circuit schematic diagram of a fire detector according to some embodiments of the present disclosure is shown.

[0036] Figure 4Shows a partial circuit schematic diagram of a fire detector according to some embodiments of the present disclosure.

[0037] Figure 5 Shows a partial circuit schematic diagram of a fire detector according to some embodiments of the present disclosure.

[0038] Figure 6 Shows an exploded schematic diagram of the overall structure of a fire detector according to some embodiments of the present disclosure.

[0039] Figure 7 Shows a schematic diagram of a fire detection system according to some embodiments of the present disclosure. Detailed implementation manners

[0040] In the following, only some exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the present disclosure. Therefore, the drawings and the description are considered to be exemplary in nature rather than restrictive.

[0041] In the description of the present disclosure, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present disclosure. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present disclosure, "a plurality" means two or more unless otherwise specifically defined.

[0042] In the description of the present disclosure, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection or can communicate with each other; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0043] In this disclosure, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may include the contact between the first and second features through additional features therebetween rather than direct contact. Moreover, the first feature being "above", "over" and "on top of" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the horizontal height of the first feature is lower than that of the second feature.

[0044] Numerous different embodiments or examples are provided hereinafter to implement different structures of the present disclosure. To simplify the present disclosure, components and settings of specific examples are described hereinafter. Of course, they are merely examples and are not intended to limit the present disclosure. In addition, the present disclosure may repeat reference numerals and / or reference letters in different examples. Such repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between various embodiments and / or settings discussed. In addition, the present disclosure provides examples of various specific processes and materials, but those of ordinary skill in the art may be aware of the application of other processes and / or the use of other materials.

[0045] The preferred embodiments of the present disclosure are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present disclosure, and are not used to limit the present disclosure.

[0046] The present disclosure provides a fire detector. Figure 1 A circuit schematic diagram of a fire detector 10 according to some embodiments of the present disclosure is shown. As Figure 1 shown, the fire detector 10 includes a voltage monitoring module 11, a current regulation module 12, and a control module 13. The voltage monitoring module 11 is used to monitor the loop voltage where the fire detector 10 is located. The current regulation module 12 is used to regulate the loop current where the fire detector 10 is located. One end of the control module 13 is connected to the voltage source VCC, and the other end is grounded to GND. The control module 13 is also connected to the voltage monitoring module 11 and the current regulation module 12, and is used to control the voltage monitoring module 11 to monitor the loop voltage and control the current regulation module 12 to regulate the loop current based on the loop voltage. The fire detector of the present disclosure can regulate the loop current so that the loop current can be kept balanced, enabling the fire detector to operate stably, improving the robustness and reliability of the fire detector, providing an important guarantee for fire safety, and being adaptable to different control panels, thus improving the versatility of the fire detector.

[0047] Figure 2 A partial circuit schematic diagram of a fire detector according to some embodiments of the present disclosure is shown. As Figure 2As shown in the figure, the control module 13 includes a first resistor R1 and a second resistor R2 connected in series. The first resistor R1 is connected to the voltage source VCC, and the second resistor R2 is grounded to GND. The voltage monitoring module 11 includes an AD converter 110, and the AD converter 110 is connected between the output terminal of the first resistor R1 and the input terminal of the second resistor R2, and collects the voltage at the output terminal.

[0048] In some embodiments, the control module 13 determines the loop voltage where the fire detector 10 is located based on the voltage at the output terminal of the first resistor R1. The loop voltage satisfies the following formula:

[0049]

[0050] where V is the loop voltage, V AD is the voltage at the output terminal of the first resistor R1, Vref is the reference voltage, R 1 is the resistance value of the first resistor R1, R 2 is the resistance value of the second resistor R2.

[0051] The above formula can represent the conversion relationship between the loop voltage V and the voltage V AD at the output terminal of the first resistor (i.e., the sampling voltage). Given the resistance values of the first resistor and the second resistor and the reference voltage, the loop voltage can be determined based on the sampling voltage. It should be noted that the present disclosure does not limit the specific values of the resistance values of the first resistor and the second resistor and the reference voltage, which can be set according to actual needs.

[0052] In some embodiments, the control module 13 determines the change amount of the loop voltage where the fire detector 10 is located, and based on the change amount, controls the current adjustment module 12 to adjust the loop current. Specifically, after the fire detector 10 is powered on, the voltage monitoring module 11 (AD converter 110) can continuously or periodically collect the voltage V AD at the output terminal of the first resistor R1. The control module 13 determines the loop voltage where the fire detector 10 is located based on the voltage V AD and the above formula. For example, at a certain moment, the loop voltage is determined to be V1, and at another moment, the loop voltage is determined to be V2. The control module 13 determines the change amount of the loop voltage as ΔV = V1 - V2, and based on the change amount ΔV of the loop voltage, controls the current adjustment module 12 to adjust the loop current I.

[0053] For example, when the change amount ΔV of the loop voltage is greater than the first threshold V TH1When the time control current regulation module 12 reduces the loop current I. The fire detector can control the loop current to maintain balance by adjusting the loop current I through the current regulation module 12, enabling the stable operation of the fire detector, improving the robustness and reliability of the fire detector, and providing an important guarantee for fire safety. The control module 13 keeps the current loop current I unchanged without adjustment when the change amount ΔV of the loop voltage is not greater than the first threshold V TH1 to keep the operation of the fire detector stable.

[0054] In some embodiments, when the change amount ΔV of the loop voltage is greater than the first threshold V TH1 the fire detector 10 alarms.

[0055] Figure 3 shows a partial circuit schematic diagram of a fire detector according to some embodiments of the present disclosure. As Figure 3 shown, the current regulation module 12 includes a first switch K1 and a third resistor R3. The first switch K1 is connected to the voltage source VCC. One end of the third resistor R3 is connected to the first switch K1, and the other end is grounded. The control module 13 controls the first switch K1 and / or the third resistor R3 to adjust the loop current. In other words, the control module 13 can control the first switch K1 to adjust the loop current. Or the control module 13 can also control the third resistor R3 to adjust the loop current. Or the control module 13 can also control both the first switch K1 and the third resistor R3 to adjust the loop current.

[0056] In some embodiments, as Figure 3 shown, the third resistor R3 can be a variable resistor. The control module 13 controls the first switch K1 to conduct and adjusts the resistance value of the third resistor R3 to adjust the loop current.

[0057] In some embodiments, the first switch K1 includes a Field-Effect Transistor (FET) switch, for example, a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET). The MOSFET may include a P-channel Metal-Oxide-Semiconductor Field-Effect Transistor (PMOS), or an N-channel Metal-Oxide-Semiconductor Field-Effect Transistor (NMOS). Alternatively, the first switch K1 may also be any other component that can perform an equivalent or similar function, including but not limited to switch devices such as a Bipolar Junction Transistor (BJT), a RELAY, or a mechanical switch.

[0058] Figure 4 The partial circuit schematic diagram of a fire detector according to some embodiments of the present disclosure is shown. As Figure 4 shown, the first switch K1 includes a MOSFET, such as an NMOS, whose drain D is connected to the voltage source VCC, the source S is connected to the third resistor R3, and the gate G is connected to the control module 13. The control module 13 controls the first switch K1 to conduct and adjusts its gate voltage to adjust the loop current.

[0059] In some embodiments, there may be multiple third resistors R3, and the multiple third resistors R3 are connected in parallel. The current regulation module 12 includes multiple second switches K2, and the second switches K2 are connected in series with the third resistors R3. The control module 13 controls the first switch K1 to conduct and controls the on / off of the second switches K2 to adjust the loop current. It should be noted that the present disclosure does not limit the number of the second switches and the third resistors, and the two may be the same or different and can be set according to requirements.

[0060] Figure 5 The partial circuit schematic diagram of a fire detector according to some embodiments of the present disclosure is shown. As Figure 5 shown, the current regulation module 12 includes, for example, n third resistors R3-1, R3-2, R3-3, R3-4,..., R3-n, and n second switches K2-1, K2-2, K2-3, K2-4,..., K2-n, where n is a positive integer, the number of the third resistors and the second switches is the same, and the third resistors and the second switches are connected in one-to-one correspondence. The control module 13 controls the first switch K1 to conduct and simultaneously controls the on / off number of the second switches K2 to achieve the regulation of the loop current.

[0061] In some embodiments, as Figures 3 to 5 shown, the current regulation module 12 further includes a fourth resistor R4, and the fourth resistor R4 is connected to the voltage source VCC and the first switch K1. The fourth resistor R4 is a variable resistor, and the control module 13 adjusts the resistance value of the fourth resistor R4 to regulate the loop current. In other embodiments, the fourth resistor R4 may be a fixed resistor for current limiting, and all of these are within the protection scope of the present disclosure. It should be understood that when the fourth resistor R4 is a variable resistor, it can also play a role in current limiting.

[0062] Figure 6 Fig. shows an exploded schematic view of the overall structure of the fire detector 10 according to some embodiments of the present disclosure. As Figure 6 shown, the fire detector 10 further includes an upper cover 14, a circuit board 15, and a rear cover 16. The circuit board 15 is located between the upper cover 14 and the rear cover 16. The voltage monitoring module 11, the current regulation module 12, and the control module 13 are integrated on the circuit board 15, which can improve the integration degree of the fire detector and realize a miniaturized design.

[0063] In some embodiments, as Figure 6 shown, the fire detector 10 further includes a base 17. The rear cover 16 covers the base 17 to isolate and support the circuit board 15. The base 17 may further include a support member.

[0064] In some embodiments, the fire detector 10 may be a smoke detector. As Figure 6 shown, the smoke detector includes a maze cover 18, a smoke maze 19, and a shielding cover 20. The maze cover 18, the smoke maze 19, and the shielding cover 20 are located between the upper cover 14 and the circuit board 15, having strong dust resistance and facilitating the entry and exit of smoke, and can sensitively and accurately sense the smoke concentration.

[0065] In some embodiments, as Figure 6 shown, the fire detector 10 further includes an infrared transmitting tube 21, an infrared receiving tube 22, and a temperature sensor (not shown in the figure) respectively coupled to the control module to sense smoke or temperature to assist in determining whether the fire detector 10 alarms. In other words, the fire detector 10 may also be an infrared detector or a temperature-sensing detector. The fire detector 10 can not only determine whether to alarm by whether the change amount ΔV of the loop voltage is greater than the first threshold V TH1 but also comprehensively determine by combining the smoke concentration sensed by the smoke maze 19, the infrared signals sensed by the infrared transmitting tube 21 and the infrared receiving tube 22, and the temperature sensed by the temperature sensor. For example, the change amount ΔV of the loop voltage, the smoke concentration, the infrared signal intensity, and the temperature may be set with the same or different weights respectively to more accurately determine whether the fire detector reaches the alarm condition, so as to alarm more accurately.

[0066] In some embodiments, although not shown in the figures, the fire detector may further include a display module and / or a voice module for displaying and / or announcing whether the fire detector alarms.

[0067] In some embodiments, the fire detector may be a non-addressable fire detector. In other words, the fire detector may operate independently.

[0068] The present disclosure also provides a fire detection system 200. Figure 7 A schematic diagram of a fire detection system 200 according to some embodiments of the present disclosure is shown. As Figure 7 shown, the fire detection system 200 includes a control panel 210 and a plurality of fire detectors 10 as described above. The plurality of fire detectors 10 are connected in parallel to the control panel 210. Specifically, for example, the fire detection system 200 includes m fire detectors, namely fire detectors 10-1, 10-2, 10-3,..., 10-m. The m fire detectors are connected in parallel and are also connected in parallel to the control panel 210, where m is a positive integer. Each fire detector 10 can monitor the loop voltage where it is located through a voltage monitoring module 11. The control panel 210 determines whether the fire detector alarms based on the loop voltage.

[0069] In some embodiments, the control panel 210 determines that there is a fire detector alarm when the change amount ΔV of the loop voltage is greater than a first threshold V TH1 . For example, the control panel 210 may communicate with the fire detector 10-1, and the fire detector 10-1 may report the change amount ΔV of the loop voltage where it is located to the control panel 210. The control panel 210 may determine that there is a fire detector (for example, one or more of the fire detectors 10-2 to 10-m) alarm when the change amount ΔV of the loop voltage is greater than the first threshold V TH1 . It should be understood that since the plurality of fire detectors are connected in parallel, when the change amount of the loop voltage reported by one of the fire detectors (for example, the fire detector 10-1) is greater than the first threshold, the plurality of fire detectors connected in parallel (for example, the fire detectors 10-1 to 10-m) may alarm simultaneously. Thus, it is possible to achieve multiple fire detectors in the same loop alarming, which is beneficial to increasing the alarm intensity and improving the reliability of the fire detection system and the ability to ensure fire safety. In some embodiments, although not shown in the figures, the control panel may include a display module and / or a voice module for synchronously displaying and / or announcing the change amount of the loop voltage reported by the fire detector and the result of whether there is a detector alarm.

[0070] In some embodiments, each fire detector may communicate with the control panel and report the change amount of the loop voltage where it is located to the control panel.

[0071] In some embodiments, when the loop voltage V of the fire detector is lower than the second threshold V TH2 , the loop current I is reduced by the current regulation module 12 to keep the loop current I balanced and keep the overall current consumption on the bus unchanged, so that both the fire detector and the control panel can give alarms, and the bus voltage can be kept constant, enabling the fire detector to operate stably, thereby improving the robustness and reliability of the fire detection system. The second threshold V TH2 is less than the first threshold V TH1 .

[0072] It should be noted that the present disclosure does not limit the specific value and adjustment range of the loop current reduced by the fire detector, which can be set according to the performance or requirements of the control panel.

[0073] The fire detection system of the present disclosure can be adapted to different control panels with high versatility by adopting the above-mentioned fire detector, and can realize alarms of multiple fire detectors. The loop current can also be adjusted by the current regulation module of the fire detector, improving the stability and reliability of the operation of the entire fire detection system.

[0074] In some embodiments, the control module / control panel may include a central processing unit (CPU), a micro control unit (MCU), and may also include other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), complex programmable logic devices (CPLDs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and other similar devices and their peripheral circuits.

[0075] Finally, it should be noted that the above are only the preferred embodiments of the present disclosure and are not used to limit the present disclosure. Although the present disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present disclosure shall be included within the protection scope of the present disclosure.

Claims

1. A fire detector, characterized in that: include: A voltage monitoring module, used to monitor the circuit voltage of the fire detector; A current regulating module, used for regulating the loop current of the fire detector; and A control module has one end connected to a voltage source and the other end grounded. The control module is also connected to the voltage monitoring module and the current regulating module to control the voltage monitoring module to monitor the loop voltage and control the current regulating module to regulate the loop current based on the loop voltage.

2. The fire detector according to claim 1, characterized in that: The control module includes a first resistor and a second resistor connected in series, the first resistor is connected to the voltage source, and the second resistor is grounded. The voltage monitoring module includes an AD converter, which is connected between the output end of the first resistor and the input end of the second resistor and collects the voltage at the output end.

3. The fire detector according to claim 2, characterized in that: The control module determines the loop voltage based on the voltage at the output end, and the loop voltage satisfies: Where V is the loop voltage, V AD is the voltage of the output end, Vref is the reference voltage, R1 is the resistance value of the first resistor, and R2 is the resistance value of the second resistor.

4. The fire detector according to claim 3, characterized in that: The control module determines a change in the loop voltage, and based on the change, controls the current regulation module to regulate the loop current.

5. The fire detector according to claim 4, characterized in that: The control module controls the current regulating module to reduce the loop current when the change amount is greater than a first threshold.

6. The fire detector according to any one of claims 1 to 5, characterized in that: The current regulating module includes a first switch and a third resistor, the first switch is connected to the voltage source, one end of the third resistor is connected to the first switch and the other end is grounded, and the control module controls the first switch and / or the third resistor to regulate the loop current.

7. The fire detector according to claim 6, characterized in that: The third resistor is a variable resistor. The control module controls the first switch to be turned on and adjusts the resistance of the third resistor to adjust the loop current.

8. The fire detector according to claim 6, characterized in that: The first switch includes a metal oxide semiconductor field effect transistor, a drain of which is connected to the voltage source, a source of which is connected to the third resistor, and a gate of which is connected to the control module. The control module controls the first switch to be turned on and adjusts its gate voltage to adjust the loop current.

9. The fire detector according to claim 6, characterized in that: There are multiple third resistors, and the multiple third resistors are connected in parallel. The fire detector also includes: multiple second switches, and the second switches are connected in series with the third resistors. The control module controls the first switch to be turned on and controls the on and off of the second switch to adjust the loop current.

10. The fire detector according to claim 6, characterized in that: The current regulating module further includes a fourth resistor, wherein the fourth resistor is connected to the voltage source and the first switch, and the control module regulates the fourth resistor to regulate the loop current.

11. The fire detector according to any one of claims 1 to 5, characterized in that: Also includes: An upper cover, a circuit board and a rear cover, wherein the circuit board is located between the upper cover and the rear cover, and the voltage monitoring module, the current regulating module and the control module are integrated on the circuit board.

12. The fire detector according to claim 11, characterized in that: Also includes: The base is covered by the back cover to isolate and support the circuit board.

13. The fire detector according to claim 12, characterized in that: The fire detector comprises a smoke detector, and the smoke detector comprises: a labyrinth cover, a smoke labyrinth and a shielding cover, and the labyrinth cover, the smoke labyrinth and the shielding cover are located between the upper cover and the circuit board.

14. The fire detector according to claim 13, characterized in that: Also includes: The infrared transmitting tube, the infrared receiving tube and the temperature sensor are respectively coupled to the control module to sense smoke or temperature to assist in determining whether the fire detector has sounded an alarm.

15. The fire detector according to any one of claims 1 to 5, characterized in that: Also includes: The display module and / or voice module are used to display and / or announce whether the fire detector has alarmed.

16. The fire detector according to any one of claims 1 to 5, characterized in that: The fire detector is a non-addressable fire detector.

17. A fire detection system, characterized in that: include: Control panel; and A plurality of fire detectors according to any one of claims 1 to 16, wherein the plurality of fire detectors are connected in parallel to the control panel, wherein: The fire detector monitors the loop voltage of the fire detector through a voltage monitoring module, and the control panel determines whether the fire detector alarms based on the loop voltage.

18. The fire detection system according to claim 17, characterized in that: The control panel determines that the fire detector alarms when the change in the loop voltage is greater than a first threshold.

19. The fire detection system according to claim 17 or 18, characterized in that: The fire detector reduces the loop current through the current regulating module when the loop voltage is lower than the second threshold.

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