Commercial power direct supply type multifunctional detector

Abstract

The utility model discloses a commercial power direct supply type multifunctional detector, which comprises a commercial power supply charging module, a first voltage reduction module, a second voltage reduction module, a carbon monoxide driving detection module, a methane driving detection module, a methane sensor, a carbon monoxide sensor and a main control module, the commercial power supply charging module comprises an AC-to-DC unit, a voltage reduction and stabilization unit, a mutual inductance unit, a current limiting unit and a charging and discharging unit, the input end of the AC-to-DC unit is connected to commercial power AC 220v voltage, and the output end of the AC-to-DC unit is connected to the input end of the voltage reduction and stabilization unit; the output end of the voltage reducing and stabilizing unit is connected to the input end of the mutual inductance unit, and the output end of the mutual inductance unit is connected to the input end of the current limiting unit. The commercial power direct supply type multifunctional detector solves the problem that in the prior art, only carbon monoxide can be monitored, but the multifunctional requirement of a customer cannot be met.

Description

Technical Field

[0001] The utility model relates to the field of gas detection, and particularly to a multi-functional detector directly powered by mains electricity. Background Technique

[0002] In order to improve the safety of gas use, the detection of gas is becoming more and more important, especially the monitoring of carbon monoxide and methane. Therefore, a multi-functional detector is needed to monitor carbon monoxide and methane together.

[0003] A Chinese patent discloses a carbon monoxide alarm circuit with an application number of: CN202323190620.X. This carbon monoxide alarm circuit includes: a control module, a carbon monoxide detection module, a power supply module, and an alarm module; the power supply module supplies power to the control module, the carbon monoxide detection module, and the alarm module; the first input / output end of the control module is connected to the carbon monoxide detection module, and the second input / output end of the control module is connected to the alarm module; the power supply module includes: an access voltage unit and a current limiting unit. The input end of the access voltage unit accesses the voltage, the output end of the access voltage unit is connected to the input end of the current limiting unit, and the current limiting unit is used to limit the access voltage unit to only access the positive power supply. The first output end and the second output end of the current limiting unit are the first output end and the second output end of the power supply module.

[0004] Although this carbon monoxide alarm circuit can solve the problem in the prior art that the access of opposite voltage cannot be restricted, it still has the following disadvantages: it cannot detect both carbon monoxide and methane, has a single function, and cannot meet the usage requirements of customers. Summary of the Utility Model

[0005] The utility model aims to provide a multi-functional detector directly powered by mains electricity to solve the problem in the prior art that it can only monitor carbon monoxide and cannot meet the multi-functional requirements of customers.

[0006] To achieve the above object, the utility model adopts the following technical solutions:

[0007] The utility model discloses a multi-functional detector directly powered by mains electricity, comprising: a mains electricity supply and charging module, a first step-down module, a second step-down module, a carbon monoxide driving and detecting module, a methane driving and detecting module, a methane sensor, a carbon monoxide sensor and a main control module; the mains electricity supply and charging module comprises: an AC-DC conversion unit, a step-down and voltage stabilizing unit, a mutual inductance unit, a current limiting unit and a charging and discharging unit. The input end of the AC-DC conversion unit is connected to the mains electricity AC 220V voltage, the output end of the AC-DC conversion unit is connected to the input end of the step-down and voltage stabilizing unit, the output end of the step-down and voltage stabilizing unit is connected to the input end of the mutual inductance unit, the output end of the mutual inductance unit is connected to the input end of the current limiting unit, the output end of the current limiting unit is connected to the charging and discharging end of the charging and discharging unit, and the charging and discharging end of the charging and discharging unit is the output end of the mains electricity supply and charging module; the output end of the mains electricity supply and charging module is connected to the input end of the first step-down module, the output end of the first step-down module supplies power to the methane driving and detecting module, and the methane driving and detecting module is connected to the methane sensor; the output end of the first step-down module is connected to the input end of the second step-down module, the output end of the second step-down module supplies power to the carbon monoxide driving and detecting module, and the carbon monoxide driving and detecting module is connected to the carbon monoxide sensor; the output ends of the carbon monoxide driving and detecting module and the methane driving and detecting module are both connected to the main control module.

[0008] Preferably, the AC-DC conversion unit is a rectifier bridge chip U3. The first input end of the rectifier bridge chip U3 is connected to the mains electricity L line, the second input end of the rectifier bridge chip U3 is connected to the mains electricity N line, the first output end of the rectifier bridge chip U3 is used for connecting to the input end of the step-down and voltage stabilizing module, and the second output end of the rectifier bridge chip U3 is grounded.

[0009] Preferably, the step-down voltage regulation unit includes: capacitor C4, capacitor C5, capacitor C8, resistor R11, resistor R12, resistor R13, resistor R14, resistor R15, resistor R16, diode D2, diode D3, and the first step-down voltage regulation chip U4. The first end of resistor R11 is the input end of the step-down voltage regulation unit. The first end of resistor R11 is connected to the positive electrode of capacitor C8. The second end of resistor R11 and the negative electrode of capacitor C8 are both connected to the cathode of diode D2. The anode of diode D2 is connected to the input end C of the first step-down voltage regulation chip U4. The positive electrode of capacitor C4 is connected to the first end of resistor R11, and the negative electrode of capacitor C4 is grounded. The first end of resistor R11 is connected to the first end of resistor R12. The second end of resistor R12 is connected to the cathode of diode D3, the positive electrode of capacitor C5, and the power supply section VCC of the first step-down voltage regulation chip U4. The E end and the CS end of the first step-down voltage regulation chip U4 are grounded through resistor R13. The negative electrode of capacitor C5 is grounded. Diode D3 is connected to the first end of resistor R15 and the first end of resistor R16 through resistor R14. The first ends of resistor R15 and resistor R16 are both connected to the FB end of the first step-down voltage regulation chip U4. The second ends of resistor R15 and resistor R16 are both grounded. The output end of the step-down voltage regulation unit includes: the first output end of the step-down voltage regulation unit, the second output end of the step-down voltage regulation unit, and the third output end of the step-down voltage regulation unit. The positive electrode of capacitor C8 is the first output end of the step-down voltage regulation unit. The anode of diode D2 is the second output end of the step-down voltage regulation unit. The anode of diode D3 is the third output end of the step-down voltage regulation unit.

[0010] Preferably, the mutual inductance unit includes: the first iron core, the second iron core, the first winding, the second winding, and the third winding. The first winding and the second winding are wound around the first iron core. The third winding is wound around the second iron core. One end of the first winding is connected to the first output end of the step-down voltage regulation unit. The other end of the first winding is connected to the second output end of the step-down voltage regulation unit. One end of the second winding is connected to the third output end of the step-down voltage regulation unit. The other end of the second winding is grounded. One end of the third winding is the output end of the mutual inductance unit. The other end of the third winding is grounded.

[0011] Preferably, the current limiting unit includes: current limiting diode D4, capacitor C6, and resistor R17. The anode of current limiting diode D4 is the input end of the current limiting unit. The cathode of current limiting diode D4 is the output end of the current limiting unit. The anode of current limiting diode D4 is connected to the positive electrode of capacitor C6. The negative electrode of capacitor C6 is connected to one end of resistor R17. The other end of resistor R17 is connected to the cathode of current limiting diode D4.

[0012] Preferably, the charge and discharge unit is a rechargeable capacitor C7. The positive electrode of rechargeable capacitor C7 is the charge and discharge end of the charge and discharge unit. The negative electrode of rechargeable capacitor C7 is grounded.

[0013] Preferably, the methane-driven detection module includes: capacitor C9, capacitor C10, resistor R18, resistor R19, resistor R20, resistor R21, resistor R22, resistor R23, and triode Q2. Both the first end and the second end of the methane sensor MQ-4 are connected to the output end of the first step-down module. The third end of the methane sensor MQ-4 is connected to one end of resistor R18 and one end of resistor R19. The other end of resistor R18 is connected to the positive electrode of capacitor C9. The other end of resistor R19 and the negative electrode of capacitor C9 are grounded. The fourth end of the methane sensor MQ-4 is connected to one end of resistor R20, one end of resistor R21, and one end of resistor R22. The other end of resistor R20 and the emitter of triode Q2 are grounded. The base of triode Q2 is connected to one end of resistor R23. The other end of resistor R23 is the control end of the methane-driven detection module. The other end of resistor R21 is connected to the collector of triode Q2. The other end of resistor R22 is connected to the positive electrode of capacitor C10. The negative electrode of capacitor C10 is grounded. The positive electrode of capacitor C9 is the first output end of the methane-driven detection module. The positive electrode of capacitor C10 is the second output end of the methane-driven detection module.

[0014] Preferably, the carbon monoxide-driven detection module includes: a sensor driving module, a current-voltage conversion module, and an anti-voltage-reverse connection module; the output end of the second step-down module supplies power to the sensor driving module. The sensor driving module drives the carbon monoxide sensor to operate. The first output end of the carbon monoxide sensor is connected to the inverting input end of the current-voltage conversion module. The second output end of the carbon monoxide sensor is connected to the non-inverting input end of the current-voltage conversion module; the output end of the second step-down module is connected to the input end of the anti-voltage-reverse connection module. The output end of the anti-voltage-reverse connection module is connected to the non-inverting input end of the current-voltage conversion module. An amplifier U1 is provided in the current-voltage conversion module. The anti-voltage-reverse connection module provides a reference voltage for the non-inverting input end of amplifier U1. The current-voltage conversion module is used to convert the current from the first output end to the second output end of the carbon monoxide sensor into a voltage; the output end of the current-voltage conversion module is connected to the main control module.

[0015] Compared with the prior art, the utility model has the following beneficial effects:

[0016] In this application, first, a methane-driven detection module is set up to drive the methane sensor, and after the methane sensor is driven to operate, the voltages at the third and fourth terminals of the methane sensor are detected, thereby realizing the detection of methane concentration. Then, a carbon monoxide-driven detection module is designed to enable the carbon monoxide sensor to be powered under drive, ensuring that the carbon monoxide sensor can operate normally, thus realizing the detection of both carbon monoxide and methane, and achieving the purpose of multi-functional detection. Subsequently, a mains power supply charging module is designed, including: an AC-DC conversion unit, a step-down voltage regulation unit, a mutual inductance unit, a current limiting unit, and a charge and discharge unit, which realizes the conversion of the mains AC 220V voltage into a DC voltage, then steps down and regulates the voltage through the step-down voltage regulation unit, and mutually inducts and transforms the voltage through the mutual inductance unit. Finally, a stable DC voltage is output through the current limiting unit. When the mains power fails, the charge and discharge unit discharges, and when the mains power is normally supplied, the charge and discharge unit is charged, thereby ensuring that the entire detector can continue to operate normally after a power outage. Finally, a first step-down module is designed to convert the DC 12V voltage output by the mains power supply charging module into a 5V voltage, and the 5V voltage provides the operating voltage for the methane-driven detection module. A second step-down module converts the DC 5V voltage output by the first step-down module into a 3.3V voltage, and the 3.3V voltage provides the operating voltage for the carbon monoxide-driven detection module.

[0017] Other advantages, objectives, and features of the present utility model will be partially reflected by the following description and partially understood by those skilled in the art through the research and practice of the present utility model. Brief Description of the Drawings

[0018] Figure 1 It is a circuit diagram of the mains power supply charging module.

[0019] Figure 2 It is a circuit diagram of the methane-driven detection module.

[0020] Figure 3 It is a circuit diagram of the carbon monoxide-driven detection module. Detailed Embodiments

[0021] In order to make the technical means, creative features, achieved objectives, and functions of the present utility model clearer and easier to understand, the present utility model will be further described below in conjunction with the drawings and specific embodiments:

[0022] As Figures 1 to 3As shown in the figure, the utility model discloses a multi-functional detector directly powered by mains electricity, which includes: a mains electricity supply and charging module, a first step-down module, a second step-down module, a carbon monoxide drive and detection module, a methane drive and detection module, a methane sensor, a carbon monoxide sensor and a main control module; the mains electricity supply and charging module includes: an AC-DC conversion unit, a step-down and voltage stabilization unit, a mutual inductance unit, a current limiting unit and a charging and discharging unit. The input end of the AC-DC conversion unit is connected to the mains electricity AC 220V voltage, the output end of the AC-DC conversion unit is connected to the input end of the step-down and voltage stabilization unit, the output end of the step-down and voltage stabilization unit is connected to the input end of the mutual inductance unit, the output end of the mutual inductance unit is connected to the input end of the current limiting unit, the output end of the current limiting unit is connected to the charging and discharging end of the charging and discharging unit, and the charging and discharging end of the charging and discharging unit is the output end of the mains electricity supply and charging module; the output end of the mains electricity supply and charging module is connected to the input end of the first step-down module, the output end of the first step-down module supplies power to the methane drive and detection module, and the methane drive and detection module is connected to the methane sensor; the output end of the first step-down module is connected to the input end of the second step-down module, the output end of the second step-down module supplies power to the carbon monoxide drive and detection module, and the carbon monoxide drive and detection module is connected to the carbon monoxide sensor; the output ends of the carbon monoxide drive and detection module and the methane drive and detection module are both connected to the main control module.

[0023] The AC-DC conversion unit is a rectifier bridge chip U3. The first input end of the rectifier bridge chip U3 is connected to the mains electricity L wire, the second input end of the rectifier bridge chip U3 is connected to the mains electricity N wire, the first output end of the rectifier bridge chip U3 is used to connect to the input end of the step-down and voltage stabilization module, and the second output end of the rectifier bridge chip U3 is grounded. It realizes the conversion of the mains electricity AC 220V voltage into a DC voltage, which is convenient for subsequent step-down and voltage stabilization processing. A fuse F1 is connected between the first input end of the rectifier bridge chip U3 and the mains electricity L wire, and a voltage stabilizing resistor RV is connected between the mains electricity L wire and the mains electricity N wire.

[0024] The step-down voltage regulation unit includes: capacitor C4, capacitor C5, capacitor C8, resistor R11, resistor R12, resistor R13, resistor R14, resistor R15, resistor R16, diode D2, diode D3, and the first step-down voltage regulation chip U4. The first end of resistor R11 is the input end of the step-down voltage regulation unit. The first end of resistor R11 is connected to the positive electrode of capacitor C8. The second end of resistor R11 and the negative electrode of capacitor C8 are both connected to the cathode of diode D2. The anode of diode D2 is connected to the input end C of the first step-down voltage regulation chip U4. The positive electrode of capacitor C4 is connected to the first end of resistor R11, and the negative electrode of capacitor C4 is grounded. The first end of resistor R11 is connected to the first end of resistor R12. The second end of resistor R12 is connected to the cathode of diode D3, the positive electrode of capacitor C5, and the power supply section VCC of the first step-down voltage regulation chip U4. The E end and CS end of the first step-down voltage regulation chip U4 are grounded through resistor R13. The negative electrode of capacitor C5 is grounded. Diode D3 is connected to the first end of resistor R15 and the first end of resistor R16 through resistor R14. The first end of resistor R15 and the first end of resistor R16 are both connected to the FB end of the first step-down voltage regulation chip U4. The second end of resistor R15 and the second end of resistor R16 are both grounded. The output end of the step-down voltage regulation unit includes: the first output end of the step-down voltage regulation unit, the second output end of the step-down voltage regulation unit, and the third output end of the step-down voltage regulation unit. The positive electrode of capacitor C8 is the first output end of the step-down voltage regulation unit. The anode of diode D2 is the second output end of the step-down voltage regulation unit. The anode of diode D3 is the third output end of the step-down voltage regulation unit. The first step-down voltage regulation chip U4 uses a PT2332EU model chip.

[0025] The mutual inductance unit includes: the first iron core, the second iron core, the first winding, the second winding, and the third winding. The first winding and the second winding are wound around the first iron core. The third winding is wound around the second iron core. One end of the first winding is connected to the first output end of the step-down voltage regulation unit, and the other end of the first winding is connected to the second output end of the step-down voltage regulation unit. One end of the second winding is connected to the third output end of the step-down voltage regulation unit, and the other end of the second winding is grounded. One end of the third winding is the output end of the mutual inductance unit, and the other end of the third winding is grounded. The mutual inductance unit realizes voltage transformation through electromagnetic induction and also plays a role in separating the power supply circuit from the previous AC-to-DC circuit, step-down voltage regulation circuit, etc., to protect the subsequent electrical components.

[0026] The current limiting unit includes a current limiting diode D4, a capacitor C6, and a resistor R17. The anode of the current limiting diode D4 is the input end of the current limiting unit, and the cathode of the current limiting diode D4 is the output end of the current limiting unit. The anode of the current limiting diode D4 is connected to the positive electrode of the capacitor C6, the negative electrode of the capacitor C6 is connected to one end of the resistor R17, and the other end of the resistor R17 is connected to the cathode of the current limiting diode D4. The capacitor C6 and the resistor R17 play a voltage stabilizing role. The current limiting diode D4 limits the reverse flow of current, avoiding the consumption of electrical energy by the electrical components in front of the current limiting diode D4 when the rechargeable capacitor C7 discharges, and reducing energy consumption.

[0027] The charge and discharge unit is a rechargeable capacitor C7. The positive electrode of the rechargeable capacitor C7 is the charge and discharge end of the charge and discharge unit, and the negative electrode of the rechargeable capacitor C7 is grounded. It realizes automatic discharge when there is no mains power supply to keep the entire detector in a working state all the time.

[0028] The methane-driven detection module includes a capacitor C9, a capacitor C10, a resistor R18, a resistor R19, a resistor R20, a resistor R21, a resistor R22, a resistor R23, and a triode Q2. The first end and the second end of the methane sensor MQ-4 are both connected to the output end of the first step-down module. The third end of the methane sensor MQ-4 is connected to one end of the resistor R18 and one end of the resistor R19. The other end of the resistor R18 is connected to the positive electrode of the capacitor C9, and the other end of the resistor R19 and the negative electrode of the capacitor C9 are grounded. The fourth end of the methane sensor MQ-4 is connected to one end of the resistor R20, one end of the resistor R21, and one end of the resistor R22. The other end of the resistor R20 and the emitter of the triode Q2 are grounded. The base of the triode Q2 is connected to one end of the resistor R23, and the other end of the resistor R23 is the control end of the methane-driven detection module. The other end of the resistor R21 is connected to the collector of the triode Q2. The other end of the resistor R22 is connected to the positive electrode of the capacitor C10, and the negative electrode of the capacitor C10 is grounded. The positive electrode of the capacitor C9 is the first output end of the methane-driven detection module, and the positive electrode of the capacitor C10 is the second output end of the methane-driven detection module. Both the first output end and the second output end of the methane-driven detection module are connected to the main control module. By analyzing the voltages at the first output end and the second output end of the methane-driven detection module, the methane concentration in the environment where the current methane sensor is located can be known, and an alarm prompt is realized when the methane concentration is too high.

[0029] The carbon monoxide drive detection module includes: a sensor drive module, a current-voltage conversion module, and an anti-reverse voltage connection module; the output end of the second step-down module supplies power to the sensor drive module, the sensor drive module drives the carbon monoxide sensor to operate, the first output end of the carbon monoxide sensor is connected to the inverting input end of the current-voltage conversion module, and the second output end of the carbon monoxide sensor is connected to the non-inverting input end of the current-voltage conversion module; the output end of the second step-down module is connected to the input end of the anti-reverse voltage connection module, the output end of the anti-reverse voltage connection module is connected to the non-inverting input end of the current-voltage conversion module, an amplifier U1 is provided in the current-voltage conversion module, the anti-reverse voltage connection module provides a reference voltage for the non-inverting input end of the amplifier U1, and the current-voltage conversion module is used to convert the current from the first output end to the second output end of the carbon monoxide sensor into a voltage; the output end of the current-voltage conversion module is connected to the main control module. First, the second step-down module is used to provide a voltage, which is a DC 3.3V; then, a sensor drive module is provided, and through the power supply of the second step-down module, the first end and the second end of the carbon monoxide sensor are loaded with voltage, so that there is current passing through the carbon monoxide sensor; then, a current-voltage conversion module with an amplifier U1 is designed to convert the current passing through the carbon monoxide sensor into a voltage. At the same time, in order to cooperate with the operation of the current-voltage conversion module with an amplifier U1, the second step-down module is designed to provide a reference voltage for the current-voltage conversion module with an amplifier U1 through the anti-reverse voltage connection module, so that the current-voltage conversion module with an amplifier U1 can operate, and the anti-reverse voltage connection module can avoid accessing negative voltage, ensuring that the current-voltage conversion module with an amplifier U1 can operate normally.

[0030] The voltage output type carbon monoxide detection circuit further includes: an injection detection module, the input end of the injection detection module is connected to the voltage output end CO-ERR of the main control module, and the output end of the injection detection module is connected to the non-inverting input end of the current-voltage conversion module.

[0031] The sensor drive module includes: a resistor R1 and a field effect transistor Q1. One end of the resistor R1 is used to connect to the output end of the power supply module, the other end of the resistor R1 is connected to the gate of the field effect transistor Q1, the source of the field effect transistor Q1 is connected to the first end of the carbon monoxide sensor CO, and the drain of the field effect transistor Q1 is connected to the second end of the carbon monoxide sensor CO. The field effect transistor Q1 is turned on only after a +3.3V voltage is output at the output end of the power supply module, so that there is current passing through the carbon monoxide sensor CO.

[0032] The current-voltage conversion module includes: resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, and capacitor C1. The first end of resistor R2 is connected to one end of resistor R3, and the second end of resistor R2 is connected to the non-inverting input terminal of amplifier U1. The first end of resistor R2 is the non-inverting input terminal of the current-voltage conversion module. The other end of resistor R3 is connected to the first end of resistor R4. The second end of resistor R4 is connected to the inverting input terminal of amplifier U1. The first end of resistor R4 is the inverting input terminal of the current-voltage conversion module. The second end of resistor R4 is connected to one end of resistor R5 and the positive electrode of capacitor C1. The negative electrode of capacitor C1 and the other end of resistor R5 are connected to the output terminal of amplifier U1. The output terminal of amplifier U1 is connected to one end of resistor R6. The other end of resistor R6 is the output terminal of the current-voltage conversion module.

[0033] The reverse voltage protection module includes: resistor R7, resistor R8, resistor R9, and capacitor C3. The first end of resistor R7 is the input terminal of the reverse voltage protection module. The second end of resistor R7 and one end of resistor R8 are both connected to the non-inverting input terminal of follower U2. The other end of resistor R8 is grounded. The inverting input terminal of follower U2 is connected to the output terminal of follower U2. The high-voltage power supply terminal of follower U2 is connected to the output terminal of the power supply module and the positive electrode of capacitor C3. The negative electrode of capacitor C3 is grounded. Follower U2 is connected to one end of resistor R9. The other end of resistor R9 is the output terminal of the reverse voltage protection module. The voltage at the non-inverting input terminal of follower U2 is equal to the voltage at the output terminal, which has the effect of preventing the 3.3V voltage from being connected reversely.

[0034] The injection detection module includes: resistor R10 and current-limiting diode D1. The first end of resistor R10 is the input terminal of the injection detection module. The second end of resistor R10 is connected to the anode of current-limiting diode D1. The cathode of current-limiting diode D1 is the output terminal of the injection detection module. When the voltage output terminal CO-ERR of the main control module outputs a detection voltage, the detection voltage reaches the non-inverting input terminal of the current-voltage conversion module after passing through resistor R10 and current-limiting diode D1. If the carbon monoxide sensor is damaged, the voltage output by the output terminal ADC-CO of the current-voltage conversion module will be different from the normal voltage, thereby realizing the monitoring of whether the carbon monoxide sensor is damaged. The current-limiting diode D1 restricts the reverse flow of current into the voltage output terminal CO-ERR of the main control module, which may cause damage to the main control module, playing a role in protecting the main control module.

[0035] The output terminal ADC-CO of the current-voltage conversion module is connected to the positive electrode of capacitor C2, and the negative electrode of capacitor C2 is grounded. To stabilize the output voltage of the output terminal ADC-CO of the current-voltage conversion module.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model and not to limit them. Although the present utility model has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present utility model can be modified or equivalently replaced without departing from the purpose and scope of the technical solutions of the present utility model, and they should all be covered within the scope of the claims of the present utility model.

Claims

1. A multifunctional detector directly supplied by mains electricity, characterized in that: include: A mains power supply charging module, a first step-down module, a second step-down module, a carbon monoxide drive detection module, a methane drive detection module, a methane sensor, a carbon monoxide sensor and a main control module; The mains power supply charging module includes: an AC-to-DC unit, a step-down voltage stabilizing unit, a mutual inductance unit, a current limiting unit and a charging and discharging unit. The input end of the AC-to-DC unit is connected to the mains AC 220V voltage, the output end of the AC-to-DC unit is connected to the input end of the step-down voltage stabilizing unit, the output end of the step-down voltage stabilizing unit is connected to the input end of the mutual inductance unit, the output end of the mutual inductance unit is connected to the input end of the current limiting unit, the output end of the current limiting unit is connected to the charging and discharging end of the charging and discharging unit, and the charging and discharging end of the charging and discharging unit is the output end of the mains power supply charging module; The output end of the AC power supply charging module is connected to the input end of the first step-down module, the output end of the first step-down module supplies power to the methane drive detection module, and the methane drive detection module is connected to the methane sensor; the output end of the first step-down module is connected to the input end of the second step-down module, the output end of the second step-down module supplies power to the carbon monoxide drive detection module, and the carbon monoxide drive detection module is connected to the carbon monoxide sensor; The output end of the carbon monoxide drive detection module and the output end of the methane drive detection module are both connected to the main control module.

2. The mains-powered multifunctional detector according to claim 1, characterized in that: The AC to DC unit is a rectifier bridge chip U3, a first input terminal of the rectifier bridge chip U3 is connected to the AC power L line, a second input terminal of the rectifier bridge chip U3 is connected to the AC power N line, a first output terminal of the rectifier bridge chip U3 is used to connect to the input terminal of the step-down voltage regulator module, and a second output terminal of the rectifier bridge chip U3 is grounded.

3. The mains-powered multifunctional detector according to claim 2, characterized in that: The buck stabilizing unit includes: a capacitor C4, a capacitor C5, a capacitor C8, a resistor R11, a resistor R12, a resistor R13, a resistor R14, a resistor R15, a resistor R16, a diode D2, a diode D3 and a first buck stabilizing chip U4, wherein the first end of the resistor R11 is the input end of the buck stabilizing unit, the first end of the resistor R11 is connected to the positive electrode of the capacitor C8, the second end of the resistor R11 and the negative electrode of the capacitor C8 are both connected to the cathode of the diode D2, the anode of the diode D2 is connected to the input end C of the first buck stabilizing chip U4, the positive electrode of the capacitor C4 is connected to the first end of the resistor R11, the negative electrode of the capacitor C4 is grounded, the first end of the resistor R11 is connected to the first end of the resistor R12, the second end of the resistor R12 is connected to the cathode of the diode D3, the positive electrode of the capacitor C5 and the first buck The voltage regulator chip U4 supplies power to the segment VCC, the E end and the CS end of the first step-down voltage regulator chip U4 are grounded through the resistor R13, the negative electrode of the capacitor C5 is grounded, the diode D3 is connected to the first end of the resistor R15 and the first end of the resistor R16 through the resistor R14, the first end of the resistor R15 and the first end of the resistor R16 are both connected to the FB end of the first step-down voltage regulator chip U4, the second end of the resistor R15 and the second end of the resistor R16 are both grounded, and the output end of the step-down voltage regulator unit includes: the first output end of the step-down voltage regulator unit, the second output end of the step-down voltage regulator unit and the third output end of the step-down voltage regulator unit, the positive electrode of the capacitor C8 is the first output end of the step-down voltage regulator unit, the anode of the diode D2 is the second output end of the step-down voltage regulator unit, and the anode of the diode D3 is the third output end of the step-down voltage regulator unit.

4. The mains-powered multifunctional detector according to claim 3, characterized in that: The mutual inductance unit includes: a first iron core, a second iron core, a first winding, a second winding and a third winding. The first iron core is wound with the first winding and the second winding, the second iron core is wound with the third winding, one end of the first winding is connected to the first output end of the buck stabilizing unit, the other end of the first winding is connected to the second output end of the buck stabilizing unit, one end of the second winding is connected to the third output end of the buck stabilizing unit, the other end of the second winding is grounded, one end of the third winding is the output end of the mutual inductance unit, and the other end of the third winding is grounded.

5. The mains-powered multifunctional detector according to claim 4, characterized in that: The current limiting unit includes: a current limiting diode D4, a capacitor C6 and a resistor R17, the anode of the current limiting diode D4 is the input end of the current limiting unit, the cathode of the current limiting diode D4 is the output end of the current limiting unit, the anode of the current limiting diode D4 is connected to the positive electrode of the capacitor C6, the negative electrode of the capacitor C6 is connected to one end of the resistor R17, and the other end of the resistor R17 is connected to the cathode of the current limiting diode D4.

6. The mains-powered multifunctional detector according to claim 5, characterized in that: The charging and discharging unit is a chargeable capacitor C7, the positive electrode of the chargeable capacitor C7 is the charging and discharging end of the charging and discharging unit, and the negative electrode of the chargeable capacitor C7 is grounded.

7. The mains-powered multifunctional detector according to claim 1, characterized in that: The methane drive detection module includes: capacitor C9, capacitor C10, resistor R18, resistor R19, resistor R20, resistor R21, resistor R22, resistor R23 and transistor Q2. The first and second ends of the methane sensor MQ-4 are connected to the output end of the first step-down module. The third end of the methane sensor MQ-4 is connected to one end of the resistor R18 and one end of the resistor R19. The other end of the resistor R18 is connected to the positive electrode of the capacitor C9. The other end of the resistor R19 and the negative electrode of the capacitor C9 are grounded. The fourth end of the methane sensor MQ-4 is connected to the positive electrode of the capacitor C9. One end of resistor R20, one end of resistor R21 and one end of resistor R22, the other end of resistor R20 and the emitter of transistor Q2 are grounded, the base of transistor Q2 is connected to one end of resistor R23, the other end of resistor R23 is the control end of the methane drive detection module, the other end of resistor R21 is connected to the collector of transistor Q2, the other end of resistor R22 is connected to the positive electrode of capacitor C10, the negative electrode of capacitor C10 is grounded, the positive electrode of capacitor C9 is the first output end of the methane drive detection module, and the positive electrode of capacitor C10 is the second output end of the methane drive detection module.

8. The mains-powered multifunctional detector according to claim 1, characterized in that: The carbon monoxide drive detection module includes: a sensor drive module, a current-voltage conversion module, and a voltage reverse connection protection module; The output end of the second step-down module supplies power to the sensor driving module, which drives the carbon monoxide sensor to operate. The first output end of the carbon monoxide sensor is connected to the inverting input end of the current-voltage conversion module, and the second output end of the carbon monoxide sensor is connected to the non-inverting input end of the current-voltage conversion module. The output end of the second step-down module is connected to the input end of the anti-voltage reverse connection module, and the output end of the anti-voltage reverse connection module is connected to the non-inverting input end of the current-voltage conversion module. The current-voltage conversion module is provided with an amplifier U1, and the anti-voltage reverse connection module provides a reference voltage for the non-inverting input end of the amplifier U1. The current-voltage conversion module is used to convert the current from the first output end to the second output end of the carbon monoxide sensor into a voltage; The output end of the current-voltage conversion module is connected to the main control module.

Images