Fire-fighting detection alarm

Abstract

The utility model discloses a fire-fighting detection alarm, which relates to the technical field of fire-fighting alarms and comprises a power supply module used for supplying power; the smoke detection module is used for detecting smoke concentration; the concentration detection module is used for setting a first concentration threshold value and a second concentration threshold value and judging the smoke concentration grade; the change detection module is used for setting timing time and judging the rising rate of the smoke concentration within the timing time; the frequency adjusting module is used for adjusting the frequency of the output signal of the oscillation control module according to the concentration grade detected by the concentration detection module and the smoke concentration rising rate; and the oscillation control module is used for controlling the alarm module to carry out low-frequency alarm, second-stage alarm and first-stage alarm work. The fire-fighting detection alarm can realize different levels of fire alarm according to the smoke concentration level and the smoke concentration rising rate, timely and effectively provides fire information for personnel, and the intelligent degree of the alarm is high.

Description

Technical Field

[0001] The utility model relates to the technical field of fire alarms, in particular to a fire detection alarm. Background Art

[0002] Fire detection alarm is one of the most important means to prevent fire. It is an alarm that generates an alarm when a fire is caused by detecting smoke, heat, etc. The fire detection alarm in the prior art is generally composed of a smoke sensor, an oscillation control circuit composed of a 555 integrated circuit, and an alarm component. The smoke sensor detects the smoke concentration, and when the smoke concentration reaches the set value, the oscillation control circuit controls the alarm to alarm. Although the fire alarm is realized, due to the low intelligence level of the alarm, the alarm frequency cannot be automatically adjusted according to the smoke concentration, nor can the alarm frequency be adjusted according to the rate of change of the smoke concentration, so that people at the fire scene cannot effectively judge the alarm information in a timely manner, so it needs to be improved. Utility Model Content

[0003] The embodiment of the utility model provides a fire detection alarm to solve the problems raised in the above background technology.

[0004] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0005] A fire detection alarm, comprising: a power supply module, a smoke detection module, a concentration detection module, a change detection module, a frequency adjustment module, an oscillation control module and an alarm module;

[0006] The power module is used to receive AC power and perform rectification, filtering and voltage stabilization on the AC power to output DC power;

[0007] a smoke detection module, connected to the power module, for detecting smoke concentration and outputting a first detection signal when receiving direct current power;

[0008] a concentration detection module, connected to the smoke detection module and the power supply module, for receiving direct current power and setting a first concentration threshold and a second concentration threshold, outputting a first control signal when a first detection signal is greater than the first concentration threshold, and outputting a second control signal when the first detection signal is greater than the second concentration threshold;

[0009] a change detection module, connected to the power module, the smoke detection module and the concentration detection module, for receiving direct current power and the first control signal and setting a timing time, and when receiving the second control signal within the timing time, performing signal self-locking and outputting a third control signal;

[0010] A frequency adjustment module, connected to the change detection module, the concentration detection module and the oscillation control module, configured to output a first level signal to adjust the frequency of the first pulse signal output by the oscillation control module when receiving the second control signal, and output a second level signal to adjust the frequency of the second pulse signal output by the oscillation control module when receiving the third control signal;

[0011] an oscillation control module, connected to the power supply module and the concentration detection module, and configured to receive direct current power, and upon receiving a first control signal, oscillate and output a first pulse signal, upon receiving a first level signal output by the frequency adjustment module, adjust the frequency of the first pulse signal and output a second pulse signal, and upon receiving a second level signal output by the frequency adjustment module, adjust the frequency of the second pulse signal and output a third pulse signal;

[0012] The alarm module is connected to the oscillation control module and is used to perform the third level alarm when receiving the first pulse signal, perform the second level alarm when receiving the second pulse signal, and perform the first level alarm when receiving the third pulse signal.

[0013] As a further solution of the utility model: the power module includes a power interface, a first rectifier, a first capacitor, a first voltage stabilizer and a second capacitor; the smoke detection module includes a first sensor and a first potentiometer;

[0014] Preferably, the first end and the second end of the power interface are respectively connected to the first input end and the second input end of the first rectifier, the first output end of the first rectifier is connected to the third end of the first voltage regulator and one end of the first capacitor, the second end of the first voltage regulator is connected to one end of the second capacitor and the VCC end of the first sensor, the GND end of the first sensor, the other end of the second capacitor, the other end of the first capacitor, the first end of the first voltage regulator and the second output end of the first rectifier are all grounded, the OUT end of the first sensor is connected to one end of the first potentiometer, the other end of the first potentiometer is grounded, and the slider end of the first potentiometer is connected to the concentration detection module.

[0015] As a further solution of the utility model: the concentration detection module includes a first comparator, a first resistor, a second resistor, a third resistor, a fourth resistor and a second comparator;

[0016] Preferably, the in-phase end of the first comparator and the in-phase end of the second comparator are both connected to the slider end of the first potentiometer, the inverting end of the first comparator is connected to the first end of the first resistor and is grounded through the second resistor, the second end of the first resistor is connected to the first end of the third resistor and the second end of the first voltage regulator, the second end of the third resistor is connected to the inverting end of the second comparator and is grounded through a fourth resistor, the output end of the first comparator is connected to the change detection module and the oscillation control module, and the output end of the second comparator is connected to the frequency adjustment module.

[0017] As a further solution of the utility model: the oscillation control module includes a fifth resistor, an eighth resistor, a second potentiometer, a third capacitor, a first oscillator and a fourth capacitor; the alarm module includes a fifth capacitor and a first speaker;

[0018] Preferably, one end of the eighth resistor is connected to the second end of the first voltage regulator and the eighth end of the first oscillator, the other end of the eighth resistor is connected to the seventh end of the first oscillator and one end of the second potentiometer, the other end of the second potentiometer is connected to the sixth end of the first oscillator, the second end of the first oscillator and the slider end of the second potentiometer and is grounded through a third capacitor, the fifth end of the first oscillator is grounded through a fourth capacitor, the third end of the first oscillator is connected to the first end of the first speaker through a fifth capacitor, the second end of the first speaker is grounded, and the fourth end of the first oscillator is connected to the output end of the first comparator through a fifth resistor.

[0019] As a further solution of the utility model: the frequency adjustment module includes a sixth resistor, a seventh resistor, a first switch tube and a second switch tube;

[0020] Preferably, one end of the sixth resistor is connected to the seventh end of the first oscillator and one end of the seventh resistor, the other end of the sixth resistor is connected to the collector of the second switching tube, the other end of the seventh resistor is connected to the collector of the first switching tube, the emitter of the first switching tube and the emitter of the second switching tube are both connected to the second end of the first oscillator, the base of the second switching tube is connected to the change detection module, and the base of the first switching tube is connected to the output end of the second comparator.

[0021] As a further solution of the utility model: the change detection module includes a ninth resistor, a third switch tube, a tenth resistor, a sixth capacitor, an eleventh resistor, a twelfth resistor, a first diode, a fourth switch tube, a second diode and a first logic chip;

[0022] Preferably, the base of the third switching tube is connected to the output end of the first comparator through a ninth resistor, the collector of the third switching tube is connected to the second end of the first regulator and is connected to the collector of the fourth switching tube and the anode of the first diode through a twelfth resistor, the base of the fourth switching tube is connected to one end of the sixth capacitor, one end of the tenth resistor and the emitter of the third switching tube through an eleventh resistor, the emitter of the fourth switching tube, the other end of the sixth capacitor and the other end of the tenth resistor are all grounded, the cathode of the first diode is connected to the cathode of the second diode and the A end of the first logic chip, the B end of the first logic chip is connected to the output end of the second comparator, and the F end of the first logic chip is connected to the anode of the second diode and the base of the first switching tube.

[0023] Compared with the prior art, the beneficial effects of the utility model are as follows: the fire detection alarm of the utility model uses a smoke detection module to perform smoke detection, and can be divided into two smoke concentration states in conjunction with the first concentration threshold and the second concentration threshold set by the concentration detection module. When the detected signal exceeds the first concentration threshold, the oscillation control module will oscillate and control the alarm module to perform a third-level alarm. When the detected signal exceeds the second concentration threshold, the oscillation control module controls the alarm module to perform a second-level alarm. At the same time, when the detected signal exceeds the first concentration threshold but does not exceed the second concentration threshold, the change detection module determines whether the detected signal exceeds the second concentration threshold within the set timing time, and when it exceeds, the oscillation control module controls the alarm module to perform a first-level alarm, thereby realizing different levels of fire alarms, providing personnel with fire information in a timely and effective manner, and the alarm has a high degree of intelligence. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the description of the embodiments of the utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 The present invention provides a schematic block diagram of a fire detection alarm.

[0026] Figure 2 A circuit diagram of a fire detection alarm provided in an example of the utility model.

[0027] Figure 3 This is a connection circuit diagram of a change detection module provided in an example of the utility model. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0029] In one embodiment, see Figure 1 , a fire detection alarm, comprising: a power supply module 1, a smoke detection module 2, a concentration detection module 3, a change detection module 4, a frequency adjustment module 5, an oscillation control module 6 and an alarm module 7;

[0030] Specifically, the power module 1 is used to receive AC power and perform rectification, filtering and voltage stabilization on the AC power to output DC power;

[0031] The smoke detection module 2 is connected to the power module 1 and is used to detect the smoke concentration and output a first detection signal when receiving DC power;

[0032] A concentration detection module 3, connected to the smoke detection module 2 and the power supply module 1, for receiving direct current power and setting a first concentration threshold and a second concentration threshold, outputting a first control signal when a first detection signal is greater than the first concentration threshold, and outputting a second control signal when the first detection signal is greater than the second concentration threshold;

[0033] The change detection module 4 is connected to the power module 1, the smoke detection module 2 and the concentration detection module 3, and is used to receive the DC power and the first control signal and set the timing time. When the second control signal is received within the timing time, the signal is self-locked and a third control signal is output;

[0034] The frequency adjustment module 5 is connected to the change detection module 4, the concentration detection module 3 and the oscillation control module 6, and is used to output a first level signal to adjust the frequency of the first pulse signal output by the oscillation control module 6 when receiving the second control signal, and output a second level signal and adjust the frequency of the second pulse signal output by the oscillation control module 6 when receiving the third control signal;

[0035] An oscillation control module 6, connected to the power supply module 1 and the concentration detection module 3, for receiving direct current power, and oscillating and outputting a first pulse signal when receiving a first control signal, adjusting the frequency of the first pulse signal and outputting a second pulse signal when receiving a first level signal output by the frequency adjustment module 5, and adjusting the frequency of the second pulse signal and outputting a third pulse signal when receiving a second level signal output by the frequency adjustment module 5;

[0036] The alarm module 7 is connected to the oscillation control module 6, and is used to perform the third level alarm when receiving the first pulse signal, perform the second level alarm when receiving the second pulse signal, and perform the first level alarm when receiving the third pulse signal.

[0037] In a specific embodiment, the power supply module 1 may adopt a power supply circuit composed of a power supply interface, a rectifier, a voltage stabilizer, etc., which may be connected to AC power and perform rectification, filtering and voltage stabilization on the AC power; the smoke detection module 2 may adopt a smoke concentration detection circuit composed of a smoke sensor and a potentiometer, which may detect the smoke concentration and output it in the form of an electrical signal; the concentration detection module 3 may adopt a concentration detection circuit composed of a resistor and a comparator, which may set a first concentration threshold and a second concentration threshold, the first concentration threshold being used as the critical value for the alarm, and the voltage of the second concentration threshold being greater than the voltage of the first concentration threshold, and the smoke concentration may be judged by judging the size of the signal detected by the smoke detection module 2 and the first concentration threshold or the second concentration threshold; the change detection module 4 may adopt a change detection circuit composed of a resistor, a transistor, a logic chip, a capacitor, etc., which may set a timing time and output it in the form of an electrical signal. When the signal detected by the fog detection module 2 is greater than the first concentration threshold, the timing operation starts to determine whether the signal detected by the smoke detection module 2 is greater than the second concentration threshold within the timing time, and then the smoke concentration rising rate is determined; the frequency adjustment module 5 can adopt a frequency adjustment circuit composed of a transistor and a resistor, etc., and adjust the frequency of the output signal of the oscillation control module 6 by adjusting the time constant of the oscillation control module 6; the oscillation control module 6 can adopt an oscillation control circuit composed of a potentiometer, a capacitor, an oscillator, etc., and when the signal detected by the smoke detection module 2 is greater than the first concentration threshold, the oscillation operation starts and the first pulse signal is output, and the frequency of the first pulse signal is adjusted by the frequency adjustment module 5; the alarm module 7 can adopt an alarm circuit composed of a capacitor and a speaker, and the frequency of the signal output by the oscillation control module 6 is controlled to achieve the third level alarm, the second level alarm and the first level alarm.

[0038] In another embodiment, see Figure 1 , Figure 2 and Figure 3 The power module 1 includes a power interface, a first rectifier T1, a first capacitor C1, a first voltage regulator IC1 and a second capacitor C2; the smoke detection module 2 includes a first sensor IC2 and a first potentiometer RP1;

[0039] Specifically, the first end and the second end of the power interface are respectively connected to the first input end and the second input end of the first rectifier T1, the first output end of the first rectifier T1 is connected to the third end of the first voltage regulator IC1 and one end of the first capacitor C1, the second end of the first voltage regulator IC1 is connected to one end of the second capacitor C2 and the VCC end of the first sensor IC2, the GND end of the first sensor IC2, the other end of the second capacitor C2, the other end of the first capacitor C1, the first end of the first voltage regulator IC1 and the second output end of the first rectifier T1 are all grounded, the OUT end of the first sensor IC2 is connected to one end of the first potentiometer RP1, the other end of the first potentiometer RP1 is grounded, and the slider end of the first potentiometer RP1 is connected to the concentration detection module 3.

[0040] In a specific embodiment, the first voltage regulator IC1 may be a 7805 voltage regulator; the first sensor IC2 may be a QM-25 smoke sensor.

[0041] Further, the concentration detection module 3 includes a first comparator A1, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4 and a second comparator A2;

[0042] Specifically, the in-phase end of the first comparator A1 and the in-phase end of the second comparator A2 are both connected to the slider end of the first potentiometer RP1, the inverting end of the first comparator A1 is connected to the first end of the first resistor R1 and is grounded through the second resistor R2, the second end of the first resistor R1 is connected to the first end of the third resistor R3 and the second end of the first voltage regulator IC1, the second end of the third resistor R3 is connected to the inverting end of the second comparator A2 and is grounded through the fourth resistor R4, the output end of the first comparator A1 is connected to the change detection module 4 and the oscillation control module 6, and the output end of the second comparator A2 is connected to the frequency adjustment module 5.

[0043] In a specific embodiment, the first resistor R1 and the second resistor R2 provide a first concentration threshold, and the third resistor R3 and the fourth resistor R4 provide a second concentration threshold; the first comparator A1 and the second comparator A2 can both be LM358 comparators.

[0044] Further, the oscillation control module 6 includes a fifth resistor R5, an eighth resistor R8, a second potentiometer RP2, a third capacitor R3, a first oscillator IC3 and a fourth capacitor C4; the alarm module 7 includes a fifth capacitor C5 and a first speaker BL1;

[0045] Specifically, one end of the eighth resistor R8 is connected to the second end of the first voltage regulator IC1 and the eighth end of the first oscillator IC3, the other end of the eighth resistor R8 is connected to the seventh end of the first oscillator IC3 and one end of the second potentiometer RP2, the other end of the second potentiometer RP2 is connected to the sixth end of the first oscillator IC3, the second end of the first oscillator IC3 and the slider end of the second potentiometer RP2 and is grounded through the third capacitor R3, the fifth end of the first oscillator IC3 is grounded through the fourth capacitor C4, the third end of the first oscillator IC3 is connected to the first end of the first speaker BL1 through the fifth capacitor C5, the second end of the first speaker BL1 is grounded, and the fourth end of the first oscillator IC3 is connected to the output end of the first comparator A1 through the fifth resistor R5.

[0046] In a specific embodiment, the above-mentioned first oscillator IC3 can use a NE555 chip, cooperate with the eighth resistor R8, the second potentiometer RP2, the third capacitor R3, the fourth capacitor C4 and the fifth resistor R5 to perform oscillation, and output a first pulse signal, wherein the frequency of the output first pulse signal is determined by the time constant of the eighth resistor R8, the second potentiometer RP2 and the third capacitor R3.

[0047] Furthermore, the frequency adjustment module 5 includes a sixth resistor R6, a seventh resistor R7, a first switch tube V1 and a second switch tube V2;

[0048] Specifically, one end of the sixth resistor R6 is connected to the seventh end of the first oscillator IC3 and one end of the seventh resistor R7, the other end of the sixth resistor R6 is connected to the collector of the second switch tube V2, the other end of the seventh resistor R7 is connected to the collector of the first switch tube V1, the emitter of the first switch tube V1 and the emitter of the second switch tube V2 are both connected to the second end of the first oscillator IC3, the base of the second switch tube V2 is connected to the change detection module 4, and the base of the first switch tube V1 is connected to the output end of the second comparator A2.

[0049] In a specific embodiment, both the first switch tube V1 and the second switch tube V2 can be NPN transistors; the sixth resistor R6 and the seventh resistor R7 are controlled by the second switch tube V2 and the first switch tube V1 respectively to achieve parallel connection with the second potentiometer RP2.

[0050] Further, the change detection module 4 includes a ninth resistor R9, a third switch tube V3, a tenth resistor R10, a sixth capacitor C6, an eleventh resistor R11, a twelfth resistor R12, a first diode D1, a fourth switch tube V4, a second diode D2 and a first logic chip IC4;

[0051] Specifically, the base of the third switch tube V3 is connected to the output end of the first comparator A1 through the ninth resistor R9, the collector of the third switch tube V3 is connected to the second end of the first regulator IC1 and is connected to the collector of the fourth switch tube V4 and the anode of the first diode D1 through the twelfth resistor R12, the base of the fourth switch tube V4 is connected to one end of the sixth capacitor C6, one end of the tenth resistor R10 and the emitter of the third switch tube V3 through the eleventh resistor R11, the emitter of the fourth switch tube V4, the other end of the sixth capacitor C6 and the other end of the tenth resistor R10 are all grounded, the cathode of the first diode D1 is connected to the cathode of the second diode D2 and the A end of the first logic chip IC4, the B end of the first logic chip IC4 is connected to the output end of the second comparator A2, and the F end of the first logic chip IC4 is connected to the anode of the second diode D2 and the base of the first switch tube V1.

[0052] In a specific embodiment, the third switch tube V3 may be an NPN transistor to control the energy storage of the sixth capacitor C6; the fourth switch tube V4 may be an NPN transistor, and the base voltage of the fourth switch tube V4 is pulled down by the tenth resistor R10, thereby making the fourth switch tube V4 in a cut-off state. After the voltage stored in the sixth capacitor C6 reaches the turn-on voltage of the fourth switch tube V4, the fourth switch tube V4 is turned on, and the time required for the voltage stored in the sixth capacitor C6 to reach the turn-on voltage of the fourth switch tube V4 is the timing time; the first logic chip IC4 may be an AND gate chip, and cooperate with the first diode D1 and the second diode D2 to perform self-locking processing on the signal output from the A end of the first logic chip IC4.

[0053] In a fire detection alarm of the present embodiment, AC power is connected through a power interface, and the first rectifier T1, the first capacitor C1, the first voltage regulator IC1 and the second capacitor C2 perform rectification, filtering and voltage stabilization processing, and the first sensor IC2 performs smoke concentration detection and transmits it to the first potentiometer RP1 in the form of an electrical signal. When the detected signal is greater than the first concentration threshold value set by the first resistor R1 and the second resistor R2, the first comparator A1 outputs a high level and controls the first oscillator IC3 to start working, and the first oscillator IC3 cooperates with the eighth resistor R8, the second potentiometer RP2, the third capacitor R3 and the fourth capacitor C4 to perform oscillation and output a first pulse signal. At this time, the frequency of the first pulse signal can be fine-tuned by adjusting the resistance value of the second potentiometer RP2. The first pulse signal triggers the first speaker BL1 to perform a third-level alarm. At the same time, the high level output by the first comparator A1 will control the third switch tube V3 to turn on, so that the sixth capacitor C6 starts to store energy. Within the timing time set by the sixth capacitor C6 and the eleventh resistor R11, if the signal detected by the first sensor IC2 exceeds the third resistor R3 at this time, and the second concentration threshold set by the fourth resistor R4, the second comparator A2 will output a high level to control the first switch tube V1 to be turned on. At this time, the seventh resistor R7 is connected in parallel with the second potentiometer RP2, so that the frequency of the output first pulse signal increases, and the first speaker BL1 performs a second-level alarm. At the same time, the B end of the first logic chip IC4 becomes a high level. The A end of the first logic chip IC4 is provided with a high level by the first regulator IC1 because the fourth switch tube V4 is in the off state. At this time, the F end of the first logic chip IC4 will output a high level, and cooperate with the first diode D1 and the second diode D2 to perform signal self-locking, control the second switch tube V2 to be turned on, the sixth resistor R6, the seventh resistor R7 and the second potentiometer RP2 are connected in parallel, and the frequency of the signal is increased again, so that the first speaker BL1 performs a first-level alarm. If the signal detected by the first sensor IC2 exceeds the second concentration threshold set by the third resistor R3 and the fourth resistor R4 after the electric energy stored in the sixth capacitor C6 triggers the fourth switch tube V4 to be turned on, the second comparator A2 will control the first switch tube V1 to be turned on, and the first speaker BL1 performs a second-level alarm.

[0054] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-limiting from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0055] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A fire detection alarm, characterized in that: The fire detection alarm includes: a power supply module, a smoke detection module, a concentration detection module, a change detection module, a frequency adjustment module, an oscillation control module and an alarm module; The power module is used to receive AC power and perform rectification, filtering and voltage stabilization on the AC power to output DC power; The smoke detection module is connected to the power supply module and is used to detect smoke concentration and output a first detection signal when receiving direct current power; The concentration detection module is connected to the smoke detection module and the power supply module, and is used to receive direct current power and set a first concentration threshold and a second concentration threshold, and output a first control signal when the first detection signal is greater than the first concentration threshold, and output a second control signal when the first detection signal is greater than the second concentration threshold; The change detection module is connected to the power module, the smoke detection module and the concentration detection module, and is used to receive DC power and the first control signal and set a timing time. When the second control signal is received within the timing time, the signal is self-locked and a third control signal is output; The frequency adjustment module is connected to the change detection module, the concentration detection module and the oscillation control module, and is used to output a first level signal to adjust the frequency of the first pulse signal output by the oscillation control module when receiving the second control signal, and output a second level signal and adjust the frequency of the second pulse signal output by the oscillation control module when receiving the third control signal; The oscillation control module is connected to the power supply module and the concentration detection module, and is used to receive direct current power, and when receiving a first control signal, oscillate and output a first pulse signal, when receiving a first level signal output by the frequency adjustment module, adjust the frequency of the first pulse signal and output a second pulse signal, and when receiving a second level signal output by the frequency adjustment module, adjust the frequency of the second pulse signal and output a third pulse signal; The alarm module is connected to the oscillation control module and is used to perform a third-level alarm when a first pulse signal is received, perform a second-level alarm when a second pulse signal is received, and perform a first-level alarm when a third pulse signal is received.

2. A fire detection alarm according to claim 1, characterized in that: The power module includes a power interface, a first rectifier, a first capacitor, a first voltage stabilizer and a second capacitor; the smoke detection module includes a first sensor and a first potentiometer; The first end and the second end of the power interface are respectively connected to the first input end and the second input end of the first rectifier, the first output end of the first rectifier is connected to the third end of the first voltage regulator and one end of the first capacitor, the second end of the first voltage regulator is connected to one end of the second capacitor and the VCC end of the first sensor, the GND end of the first sensor, the other end of the second capacitor, the other end of the first capacitor, the first end of the first voltage regulator and the second output end of the first rectifier are all grounded, the OUT end of the first sensor is connected to one end of the first potentiometer, the other end of the first potentiometer is grounded, and the slider end of the first potentiometer is connected to the concentration detection module.

3. A fire detection alarm according to claim 2, characterized in that: The concentration detection module includes a first comparator, a first resistor, a second resistor, a third resistor, a fourth resistor and a second comparator; The in-phase end of the first comparator and the in-phase end of the second comparator are both connected to the slider end of the first potentiometer, the inverting end of the first comparator is connected to the first end of the first resistor and is grounded through the second resistor, the second end of the first resistor is connected to the first end of the third resistor and the second end of the first voltage regulator, the second end of the third resistor is connected to the inverting end of the second comparator and is grounded through the fourth resistor, the output end of the first comparator is connected to the change detection module and the oscillation control module, and the output end of the second comparator is connected to the frequency adjustment module.

4. A fire detection alarm according to claim 3, characterized in that: The oscillation control module includes a fifth resistor, an eighth resistor, a second potentiometer, a third capacitor, a first oscillator and a fourth capacitor; the alarm module includes a fifth capacitor and a first speaker; One end of the eighth resistor is connected to the second end of the first voltage stabilizer and the eighth end of the first oscillator, the other end of the eighth resistor is connected to the seventh end of the first oscillator and one end of the second potentiometer, the other end of the second potentiometer is connected to the sixth end of the first oscillator, the second end of the first oscillator and the slider end of the second potentiometer and is grounded through the third capacitor, the fifth end of the first oscillator is grounded through the fourth capacitor, the third end of the first oscillator is connected to the first end of the first speaker through the fifth capacitor, the second end of the first speaker is grounded, and the fourth end of the first oscillator is connected to the output end of the first comparator through the fifth resistor.

5. A fire detection alarm according to claim 4, characterized in that: The frequency adjustment module includes a sixth resistor, a seventh resistor, a first switch tube and a second switch tube; One end of the sixth resistor is connected to the seventh end of the first oscillator and one end of the seventh resistor, the other end of the sixth resistor is connected to the collector of the second switch tube, the other end of the seventh resistor is connected to the collector of the first switch tube, the emitter of the first switch tube and the emitter of the second switch tube are both connected to the second end of the first oscillator, the base of the second switch tube is connected to the change detection module, and the base of the first switch tube is connected to the output end of the second comparator.

6. A fire detection alarm according to claim 5, characterized in that: The change detection module includes a ninth resistor, a third switch tube, a tenth resistor, a sixth capacitor, an eleventh resistor, a twelfth resistor, a first diode, a fourth switch tube, a second diode and a first logic chip; The base of the third switch tube is connected to the output end of the first comparator through a ninth resistor, the collector of the third switch tube is connected to the second end of the first regulator and is connected to the collector of the fourth switch tube and the anode of the first diode through a twelfth resistor, the base of the fourth switch tube is connected to one end of the sixth capacitor, one end of the tenth resistor and the emitter of the third switch tube through an eleventh resistor, the emitter of the fourth switch tube, the other end of the sixth capacitor and the other end of the tenth resistor are all grounded, the cathode of the first diode is connected to the cathode of the second diode and the A end of the first logic chip, the B end of the first logic chip is connected to the output end of the second comparator, and the F end of the first logic chip is connected to the anode of the second diode and the base of the first switch tube.

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