A household combustible gas detector

Abstract

This utility model discloses a household combustible gas detector, comprising: a front shell, a bottom shell connected to the front shell by a snap-fit ​​mechanism, a PCB board disposed between the front and bottom shells, a button and a light guide post disposed on the PCB board, and a solenoid valve socket wire and a power cord disposed at one end of the bottom shell; the PCB board is provided with a main control circuit, a power circuit, a solenoid valve output circuit, a gas meter output circuit, a voice alarm circuit, a gas detection circuit, an LED indicator circuit, a programming pin header interface circuit, a wireless module interface circuit, and a reading interface circuit; the corresponding terminals of the main control circuit are electrically connected to the corresponding terminals of the power circuit, the solenoid valve output circuit, the gas meter output circuit, the voice alarm circuit, the gas detection circuit, the LED indicator circuit, the programming pin header interface circuit, the wireless module interface circuit, the reading interface circuit, and the button. This utility model can quickly control the solenoid valve to close the gas pipeline and cut off the gas supply when a gas leak is detected, and simultaneously control the gas meter to stop counting to prevent further gas leakage, thus further enhancing safety.

Description

Technical Field

[0001] This utility model relates to the field of detector technology, and in particular to a household combustible gas detector. Background Technology

[0002] With the acceleration of urbanization, the use of natural gas in households is becoming increasingly common. While natural gas brings great convenience to people's lives, it also poses certain safety hazards. Gas leaks can lead to serious accidents such as fires and explosions, posing a significant threat to people's lives and property. Therefore, there is an urgent need for detectors that can detect gas leaks promptly and accurately and issue alarms.

[0003] shortcomings of existing detectors

[0004] Low detection accuracy:

[0005] Some traditional detectors use simple gas sensors, which have low accuracy in detecting combustible gases and are prone to false alarms or missed alarms. These sensors may not be able to detect low-concentration gas leaks in time, causing the optimal response time to be missed.

[0006] Some sensors have slow response times and cannot quickly issue an alarm in the early stages of a gas leak, increasing the probability of an accident.

[0007] Single function:

[0008] Traditional detectors mostly only have basic alarm functions and lack advanced features such as linkage control, fault self-diagnosis, and information storage. For example, when a gas leak is detected, they cannot automatically cut off the gas supply or activate the solenoid valve, requiring users to take manual measures, which increases processing time.

[0009] The lack of a self-test function prevents users from quickly checking whether the device is working properly before use, which may cause the device to fail to operate reliably at critical moments.

[0010] Poor power stability: Lacking backup power support, the equipment will completely fail once the mains power is interrupted, and the user's safety needs cannot be guaranteed.

[0011] Inadequate information management:

[0012] Traditional detectors lack information storage and retrieval capabilities, preventing users from accessing the device's operational history and alarm events at any time. This causes inconvenience during accident investigations and equipment maintenance, hindering the timely detection and resolution of problems. Utility Model Content

[0013] In view of the problems existing in the prior art, this utility model provides a household combustible gas detector.

[0014] To achieve the above objectives, the technical solution of this utility model is as follows:

[0015] This utility model provides a household combustible gas detector, including: a front shell, a bottom shell connected to the front shell by a snap-fit, a PCB board disposed between the front shell and the bottom shell, a button and a light guide on the PCB board, and a solenoid valve socket wire and a power cord disposed at one end of the bottom shell.

[0016] The PCB board is equipped with a main control circuit, a power supply circuit, a solenoid valve output circuit, a gas meter output circuit, a voice alarm circuit, a gas detection circuit, an LED indicator circuit, a programming pin header interface circuit, a wireless module interface circuit, and a reading interface circuit. The corresponding terminals of the main control circuit are electrically connected to the corresponding terminals of the power supply circuit, the solenoid valve output circuit, the gas meter output circuit, the voice alarm circuit, the gas detection circuit, the LED indicator circuit, the programming pin header interface circuit, the wireless module interface circuit, the reading interface circuit, and the buttons.

[0017] Preferably, the top of the faceplate has a waist-shaped opening, a button opening, and a light guide opening in sequence; one end of the button passes through the button opening, and one end of the light guide passes through the light guide opening; the bottom of the faceplate also has multiple slots.

[0018] Preferably, the inner side of the bottom shell is provided with a plurality of buckles that are adapted to the slot; one end of the bottom shell is provided with a notch, and the head of the solenoid valve socket wire and the power wire are placed at the notch, and the tail is placed outside the bottom shell.

[0019] Preferably, the main control circuit includes an MCU, the model of which is CX32L003F8P6.

[0020] Preferably, the power supply circuit includes an AC220V power interface P1, a switching power supply control circuit, a transformer circuit, a rectifier bridge circuit, an optocoupler circuit, and a battery BAT1; the corresponding terminals of the rectifier bridge circuit are electrically connected to the corresponding terminals of the AC220V power interface P1, the switching power supply control circuit, and the transformer circuit; the corresponding terminals of the transformer circuit are electrically connected to the corresponding terminals of the switching power supply control circuit, the optocoupler circuit, and the battery BAT1; the corresponding terminals of the switching power supply control circuit are also electrically connected to the corresponding terminals of the optocoupler circuit and the battery BAT1.

[0021] Preferably, the switching power supply control circuit includes a switching power supply chip DK106 and its peripheral circuits, and the optocoupler circuit includes an optocoupler chip PC817 and its peripheral circuits.

[0022] Preferably, the transformer circuit includes a transformer T1, an inductor L1, a capacitor C5, a capacitor C6, a capacitor C7, a resistor R3, a diode D6, a diode D1, a diode D3, a diode D4, a diode D5, a diode D8, a resistor R15, a resistor R2, a resistor R18, a capacitor C16, a capacitor C1, a capacitor C4, and a capacitor C2.

[0023] The first terminal of inductor L1 is electrically connected to the first terminal of capacitor C6 and the corresponding terminal of the rectifier bridge circuit. The second terminal of inductor L1 is electrically connected to the first terminals of capacitors C7 and C5, the first terminal of resistor R3, and the first pin of transformer T1. The second terminal of capacitor C6 is electrically connected to the rectifier bridge circuit, the second terminal of capacitor C7, and the corresponding terminal of switching power supply chip DK106. The second pin of transformer T1 is electrically connected to the second terminal of resistor R3 and the second terminal of capacitor C5 via diode D6.

[0024] The third pin of the transformer T1 is electrically connected to the first terminals of capacitor C1, diode D8, resistor R2, and resistor R18 via diode D1. The second terminal of resistor R18 is electrically connected to the second terminal of diode D8 and the first terminal of capacitor C16. The second terminal of capacitor C16 is grounded.

[0025] The fourth pin of the transformer T1 is electrically connected to the first terminal of capacitor C4, the corresponding terminal of optocoupler chip PC817, and the first terminal of diode D4 via diode D3 and resistor R15. The fifth pin of the transformer T1 is electrically connected to the second terminal of capacitor C4, the second terminal of capacitor C1, and the second terminal of resistor R2. The second terminal of diode D4 is electrically connected to the first terminal of capacitor C2 and the first terminal of diode D5. The second terminal of capacitor C2 is grounded, and the second terminal of diode D5 is electrically connected to the corresponding terminal of battery BAT1.

[0026] Preferably, the gas detection circuit includes a combustible gas sensor, and the corresponding terminal of the combustible gas sensor is electrically connected to the corresponding terminal of the MCU.

[0027] The technical solution of this utility model has the following beneficial effects:

[0028] High-precision detection:

[0029] Employing a high-performance planar semiconductor gas sensor (such as the MQ-4B), it exhibits high sensitivity and excellent selectivity for combustible gases such as methane, enabling accurate detection of gas leaks at low concentrations with high precision and a low false alarm rate. The sensor signal is filtered by the main control circuit (using a CX32L003F8P6 MCU), further improving signal stability and reliability, ensuring accurate gas leak detection even in complex environments.

[0030] Rapid response: The detector can monitor the concentration of combustible gas in the environment in real time. Once the gas concentration is detected to reach or exceed the alarm threshold, the alarm circuit is immediately triggered, the buzzer emits a high-decibel alarm sound, and the red light flashes to remind the user to take timely measures. The response speed is fast, effectively shortening the alarm delay time.

[0031] It has a linkage control function, which can quickly control the solenoid valve to close the gas pipeline and cut off the gas supply when a gas leak is detected. At the same time, it controls the gas meter to stop counting to prevent further gas leakage, thus further enhancing safety.

[0032] Multifunctional Integration: The device features a self-test function, which users can trigger by short-pressing a button to quickly check whether the detector's various functions are normal, including the gas detection circuit, alarm circuit, and LED indicator circuit. This ensures reliable operation in critical moments, improving equipment reliability and user confidence. LED indicator lights of different colors and flashing frequencies visually display the detector's operating status and alarm information, allowing users to easily understand whether the equipment is working properly and whether a gas leak has occurred.

[0033] The detector can store alarm and fault information. Users can connect to the information recording and reading device through the reading interface to read the device's working history and alarm events at any time, which facilitates management and maintenance.

[0034] Equipped with a backup battery (such as battery BAT1), it automatically switches to backup power in the event of a mains power outage or power interface failure, ensuring that the equipment can still work normally for a short period of time and complete the necessary alarm and linkage control functions, thus enhancing the equipment's emergency response capabilities.

[0035] Information management is well-developed:

[0036] The detector can store a certain amount of information such as alarms, alarm recovery, faults, fault recovery, power outages, power-on, and sensor failures. Users can connect an information recording and reading device to read the device's working history and alarm events at any time, which facilitates management and maintenance. Attached Figure Description

[0037] Figure 1 This is a top view of the structure of this utility model;

[0038] Figure 2 This is a side view of the structure of this utility model;

[0039] Figure 3 This is a bottom view of the structure of this utility model;

[0040] Figure 4 This is an exploded view of the structure of this utility model;

[0041] Figure 5 This is a control block diagram of the present invention;

[0042] Figure 6 This is the circuit schematic diagram of the main control circuit of this utility model;

[0043] Figure 7 This is the circuit diagram of the power supply circuit of this utility model;

[0044] Figure 8 This is a circuit diagram of the gas detection circuit of this utility model;

[0045] Figure 9 This is a circuit diagram of the output circuit of the solenoid valve of this utility model;

[0046] Figure 10 This is a circuit diagram of the output circuit of the gas meter of this utility model;

[0047] Figure 11 This is a circuit diagram of the voice alarm circuit of this utility model;

[0048] Figure 12 This is a circuit diagram of the LED indicator circuit of this utility model;

[0049] Figure 13 This is a circuit diagram of the programming pin header interface circuit of this utility model;

[0050] Figure 14 This is a circuit diagram of the wireless module interface circuit of this utility model;

[0051] Figure 15 This is a circuit diagram of the reading interface circuit of this utility model. Detailed Implementation

[0052] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0053] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0054] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0055] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0056] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0057] Reference Figures 1 to 15This utility model provides a household combustible gas detector, including: a front shell 1, a bottom shell 5 connected to the front shell 1 by a snap-fit, a PCB board 4 disposed between the front shell 1 and the bottom shell 5, a button 2 and a light guide column 3 disposed on the PCB board 4, and a solenoid valve socket wire 7 and a power cord 6 disposed at one end of the bottom shell 5; the light guide column is used in conjunction with an LED indicator light to provide users with intuitive visual guidance through light of different colors and flashing frequencies.

[0058] The PCB board 4 is provided with a main control circuit 10, a power supply circuit 50, a solenoid valve output circuit 20, a gas meter output circuit 30, a voice alarm circuit 100, a gas detection circuit 40, and an LED indicator circuit 60. The corresponding terminals of the main control circuit 10 are electrically connected to the corresponding terminals of the power supply circuit 50, the solenoid valve output circuit 20, the gas meter output circuit 30, the voice alarm circuit 100, the gas detection circuit 40, the LED indicator circuit 60, and the button 2.

[0059] Furthermore, the top of the faceplate 1 is sequentially provided with a waist-shaped opening 101, a button opening 102, and a light guide opening 103; one end of the button 2 passes through the button opening 102, and one end of the light guide post 3 passes through the light guide opening 103; the light guide opening 103 is a reserved installation position for the light guide post 3, ensuring that the light guide post 3 can be firmly installed on the faceplate 1, and can effectively guide the light of the internal LED indicator to the outside, making the indicator display clearer and more eye-catching. The bottom of the faceplate 1 is also provided with multiple slots 110, and the inner side of the bottom shell 5 is provided with multiple buckles 510 that are adapted to the slots 110, for achieving a tight connection between the faceplate 1 and the bottom shell 5. This buckle connection method is simple and quick, easy to assemble and disassemble, and can ensure the structural stability of the shell, preventing the shell from loosening or falling off during use. One end of the bottom shell 5 is provided with a notch, and the head of the solenoid valve socket wire 7 and the power wire 6 are placed in the notch, and the tail is placed outside the bottom shell 5.

[0060] Reference Figure 6 The main control circuit includes an MCU (Model CX32L003F8P6), which serves as the core control unit of the detector. The MCU coordinates and controls various circuits and functional modules of the detector, enabling the acquisition, processing, and analysis of gas detection signals. Based on the detection results, it controls the actions of the voice alarm circuit 100, the solenoid valve output circuit 20, etc., ensuring the detector operates accurately according to preset logic and programs. It possesses powerful data processing and logical judgment capabilities, enabling rapid and accurate analysis of signals from the gas detection circuit 30 to determine whether the gas concentration has reached the alarm threshold and make timely decisions, such as issuing alarm signals or controlling linked equipment, thus improving the detector's intelligence level and response speed.

[0061] Reference Figure 7The power supply circuit 50 includes an AC220V power interface P1, a switching power supply control circuit 503, a transformer circuit 502, a rectifier bridge circuit 501, an optocoupler circuit 504, and a battery BAT1. The corresponding terminals of the rectifier bridge circuit 501 are electrically connected to the corresponding terminals of the AC220V power interface P1, the switching power supply control circuit 503, and the transformer circuit 502. The corresponding terminals of the transformer circuit 502 are electrically connected to the corresponding terminals of the switching power supply control circuit 503, the optocoupler circuit 504, and the battery BAT1. The corresponding terminals of the switching power supply control circuit 503 are also electrically connected to the corresponding terminals of the optocoupler circuit 504 and the battery BAT1. The power supply circuit 50 provides a stable power supply to the detector, ensuring its normal operation. The power supply circuit uses the AC220V power interface P1, converts AC power to DC power through the rectifier bridge circuit, and then steps down the voltage through the transformer circuit to obtain a voltage suitable for the detector's operation. The switching power supply control circuit 503 uses a switching power supply chip DK106 and its peripheral circuitry to achieve efficient power conversion and stable control. The optocoupler circuit 504 uses an optocoupler chip PC817 and its peripheral circuitry to achieve electrical isolation between the power supply circuit and the main control circuit, improving the system's anti-interference capability. In addition, the power supply circuit is equipped with a battery BAT1 as a backup power source, maintaining the detector's basic functions during mains power outages and ensuring normal operation in emergencies. The switching power supply control circuit includes a switching power supply chip DK106 and its peripheral circuitry, and the optocoupler circuit includes the optocoupler chip PC817 and its peripheral circuitry.

[0062] Furthermore, the transformer circuit 502 includes a transformer T1, an inductor L1, a capacitor C5, a capacitor C6, a capacitor C7, a resistor R3, a diode D6, a diode D1, a diode D3, a diode D4, a diode D5, a diode D8, a resistor R15, a resistor R2, a resistor R18, a capacitor C16, a capacitor C1, a capacitor C4, and a capacitor C2.

[0063] The first terminal of inductor L1 is electrically connected to the first terminal of capacitor C6 and the corresponding terminal of the rectifier bridge circuit. The second terminal of inductor L1 is electrically connected to the first terminals of capacitors C7 and C5, the first terminal of resistor R3, and the first pin of transformer T1. The second terminal of capacitor C6 is electrically connected to the rectifier bridge circuit, the second terminal of capacitor C7, and the corresponding terminal of switching power supply chip DK106. The second pin of transformer T1 is electrically connected to the second terminal of resistor R3 and the second terminal of capacitor C5 via diode D6.

[0064] The third pin of the transformer T1 is electrically connected to the first terminals of capacitor C1, diode D8, resistor R2, and resistor R18 via diode D1. The second terminal of resistor R18 is electrically connected to the second terminal of diode D8 and the first terminal of capacitor C16. The second terminal of capacitor C16 is grounded.

[0065] Pin 4 of transformer T1 is electrically connected to the first terminal of capacitor C4, the corresponding terminal of optocoupler chip PC817, and the first terminal of diode D4 via diode D3 and resistor R15. Pin 5 of transformer T1 is electrically connected to the second terminals of capacitor C4, capacitor C1, and resistor R2. The second terminal of diode D4 is electrically connected to the first terminals of capacitor C2 and diode D5. The second terminal of capacitor C2 is grounded, and the second terminal of diode D5 is electrically connected to the corresponding terminal of battery BAT1. The transformer circuit, according to the requirements of the detector's internal circuitry, steps down or boosts the DC voltage output from the rectifier bridge circuit to convert it into a voltage value suitable for the various components of the detector. For example, it converts a higher input voltage to a lower operating voltage to meet the voltage requirements of low-power electronic components such as MCUs and sensors, ensuring that these components can operate under safe and stable voltage, thereby improving the overall energy efficiency and reliability of the device.

[0066] Reference Figure 8 The gas detection circuit 40 includes a combustible gas sensor, whose corresponding terminal is electrically connected to the corresponding terminal of the MCU. The gas detection circuit consists of an internal signal resistor and an external detection resistor connected in series. When combustible gas is present, the higher the gas concentration, the lower the internal signal resistance of the sensor, and the higher the voltage across the detection resistor. The voltage across the detection resistor increases with increasing gas concentration. The microcontroller samples and processes the voltage signal. When the voltage reaches or exceeds the alarm threshold, it issues an audible and visual alarm signal and simultaneously enables the linkage output. The combustible gas sensor, model MQ-4B, uses a planar semiconductor gas sensor to detect combustible gas leaks. It can detect combustible gases such as methane (CH4) with high sensitivity and fast response speed. It can quickly detect changes in gas concentration and promptly transmit the signal to the main control circuit, enabling the detector to react immediately, issue an alarm signal, and take corresponding measures. This effectively shortens the alarm delay time and improves the timeliness and accuracy of gas leak alarms.

[0067] Reference Figures 11 to 12, the voice alarm circuit 100 includes a buzzer. This voice alarm circuit can be combined with the LED indication circuit 60 to form an audible and visual alarm. By emitting a high - decibel alarm sound and a flashing red light, it can quickly attract the user's attention, timely remind the user of gas leakage, enabling the user to take corresponding measures immediately, such as closing the gas valve, opening the doors and windows for ventilation, etc., effectively reducing the safety risks brought by gas leakage. The audible and visual combined alarm method has a strong warning effect, can clearly convey the alarm information under different environmental conditions (such as noisy environments or at night), improving the effectiveness and reliability of the alarm, and ensuring that the user will not miss any important alarm prompts.

[0068] The detector also includes a self - check function, which is triggered by the button 2. The self - check function includes detecting the functional status of the gas detection circuit 40, the voice alarm circuit 100, and the LED indication circuit 60. The status indication of the LED indication circuit 60: The green light being on constantly indicates that the detector is in the normal monitoring state.

[0069] The red light flashing indicates a gas alarm. The yellow light flashing indicates a sensor failure. The yellow light being on constantly indicates a hardware failure of the sensor. Through the indicator lights of different colors and flashing frequencies, the user can intuitively understand the working status and alarm information of the detector. By short - pressing the button 2 to trigger the self - check function, the buzzer sounds for 1 second and then turns off for 2 seconds. At the same time, the green, red, and yellow LED indicator lights switch and display at a frequency of 1 second on and 1 second off. After 24 seconds, the control output interface outputs a pulse signal to drive external devices such as solenoid valves to act, which can quickly detect whether the functions of the gas detection circuit 40, the voice alarm circuit 100, the LED indication circuit 60, etc. of the detector are normal, ensuring that the device is in a good working state before normal use, improving the reliability of the device and the user's confidence in using it.

[0070] Refer to Figures 9 to 10 , the solenoid valve output circuit 20 and the gas meter output circuit 30: The solenoid valve output circuit 20 and the gas meter output circuit 30 achieve the linkage control function of the detector with external devices (such as solenoid valves and gas meters). When the detector detects that the concentration of combustible gas exceeds the safety threshold, a control signal is sent through the solenoid valve output circuit 20 to drive the solenoid valve to close the gas pipeline and cut off the gas supply; at the same time, the gas meter output circuit 30 can control the gas meter to stop counting, preventing further gas leakage, thus effectively avoiding the further expansion of gas leakage accidents and enhancing the safety of household gas use. This linkage control function realizes the automatic emergency treatment in case of gas leakage, can quickly cut off the gas source without manual intervention, greatly improving the efficiency and reliability of dealing with gas leakage accidents, and providing a more powerful guarantee for the user's life and property safety.

[0071] Furthermore, the PCB board 4 is also equipped with a programming pin header interface circuit 70, a wireless module interface circuit 80, and a reading interface circuit 90. The corresponding terminals of the programming pin header interface circuit 70, wireless module interface circuit 80, and reading interface circuit 90 are electrically connected to the corresponding terminals of the MCU. The programming pin header interface circuit 70 provides a convenient interface for programming and debugging the MCU, facilitating program updates and optimizations by developers during product development, improving development efficiency and product quality, and ensuring that the detector's various functions are accurately implemented according to design requirements. The module interface circuit 80 reserves an interface for connection to a wireless communication module, providing possibilities for functional expansion of the detector. By connecting to the wireless module, the detector can achieve wireless communication functions such as remote monitoring, alarm information push, and data upload, meeting diverse user needs in different scenarios and enhancing product competitiveness and added value. The reading interface circuit 90 is used to read alarm history records and other information stored internally in the detector. Users can easily obtain the detector's operating status and historical alarm events by connecting an information recording and reading device, facilitating equipment management and maintenance, and providing important evidence for accident investigation and analysis, enhancing the maintainability and traceability of the equipment.

[0072] The working principle of this utility model is as follows:

[0073] Gas detection circuit 40 principle

[0074] The detector uses a planar semiconductor gas sensor (such as the MQ-4B) as its core detection element. This gas sensor exhibits high sensitivity and good selectivity for combustible gases such as methane. The detection circuit consists of an internal signal resistor connected in series with an external detection resistor. When combustible gas is present in the environment, gas molecules adsorb onto the sensor surface, causing a change in the internal signal resistance value. The higher the gas concentration, the lower the signal resistance value. The voltage across the detection resistor increases with increasing gas concentration. By measuring the voltage change across the detection resistor, the concentration of combustible gas in the environment can be indirectly reflected.

[0075] The main control circuit 10 (using a CX32L003F8P6 MCU) acquires the voltage signal across the detection resistor of the gas detection circuit 40 in real time through an analog input interface. The MCU filters the acquired voltage signal to reduce external interference and false alarms.

[0076] When the detected voltage value reaches or exceeds the preset alarm threshold, the MCU determines that there is a combustible gas leak and immediately triggers the alarm circuit.

[0077] Alarm signal triggered:

[0078] When the MCU detects a combustible gas leak, it immediately triggers an alarm, with a high-decibel buzzer sounding and a flashing red LED to alert the user of the gas leak.

[0079] Linkage control:

[0080] The solenoid valve output circuit 20 and the gas meter output circuit 30 operate according to the instructions of the MCU. The MCU sends a pulse signal through the control output interface to drive the solenoid valve to close the gas pipeline and cut off the gas supply; at the same time, the gas meter output circuit 30 controls the gas meter to stop counting to prevent further gas leakage.

[0081] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. All equivalent structural transformations made under the inventive concept of the present utility model using the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A domestic combustible gas detector characterised in that, include: The front shell, the bottom shell connected to the front shell by a snap-fit ​​mechanism, the PCB board between the front shell and the bottom shell, the buttons and light guides on the PCB board, and the solenoid valve socket wire and power cord on one end of the bottom shell. The PCB board is equipped with a main control circuit, a power supply circuit, a solenoid valve output circuit, a gas meter output circuit, a voice alarm circuit, a gas detection circuit, an LED indicator circuit, a programming pin header interface circuit, a wireless module interface circuit, and a reading interface circuit. The corresponding terminals of the main control circuit are electrically connected to the corresponding terminals of the power supply circuit, the solenoid valve output circuit, the gas meter output circuit, the voice alarm circuit, the gas detection circuit, the LED indicator circuit, the programming pin header interface circuit, the wireless module interface circuit, the reading interface circuit, and the buttons.

2. The domestic combustible gas detector according to claim 1, characterized in that The top of the faceplate has a waist-shaped opening, a button opening, and a light guide opening in sequence; one end of the button passes through the button opening, and one end of the light guide column passes through the light guide opening; the bottom of the faceplate also has multiple slots.

3. The domestic combustible gas detector according to claim 2, characterized in that The inner side of the bottom shell is provided with multiple buckles that fit the slot; one end of the bottom shell is provided with a notch, and the head of the solenoid valve socket wire and the power wire are placed in the notch, while the tail is placed outside the bottom shell.

4. The domestic combustible gas detector according to claim 1, characterized in that The main control circuit includes an MCU, model number CIU32L051K8U6.

5. The domestic combustible gas detector according to claim 1, characterized in that The power supply circuit includes an AC220V power interface P1, a switching power supply control circuit, a transformer circuit, a rectifier bridge circuit, an optocoupler circuit, and a battery BAT1. The corresponding terminals of the rectifier bridge circuit are electrically connected to the corresponding terminals of the AC220V power interface P1, the switching power supply control circuit, and the transformer circuit. The corresponding terminals of the transformer circuit are electrically connected to the corresponding terminals of the switching power supply control circuit, the optocoupler circuit, and the battery BAT1. The corresponding terminals of the switching power supply control circuit are also electrically connected to the corresponding terminals of the optocoupler circuit and the battery BAT1.

6. The domestic combustible gas detector according to claim 5, characterized in that The switching power supply control circuit includes a switching power supply chip DK106 and its peripheral circuits, and the optocoupler circuit includes an optocoupler chip PC817 and its peripheral circuits.

7. The domestic combustible gas detector according to claim 6, characterized in that The transformer circuit includes transformer T1, inductor L1, capacitor C5, capacitor C6, capacitor C7, resistor R3, diode D6, diode D1, diode D3, diode D4, diode D5, diode D8, resistor R15, resistor R2, resistor R18, capacitor C16, capacitor C1, capacitor C4, and capacitor C2. The first terminal of inductor L1 is electrically connected to the first terminal of capacitor C6 and the corresponding terminal of the rectifier bridge circuit. The second terminal of inductor L1 is electrically connected to the first terminals of capacitors C7 and C5, the first terminal of resistor R3, and the first pin of transformer T1. The second terminal of capacitor C6 is electrically connected to the rectifier bridge circuit, the second terminal of capacitor C7, and the corresponding terminal of switching power supply chip DK106. The second pin of transformer T1 is electrically connected to the second terminal of resistor R3 and the second terminal of capacitor C5 via diode D6. The third pin of the transformer T1 is electrically connected to the first terminals of capacitor C1, diode D8, resistor R2, and resistor R18 via diode D1. The second terminal of resistor R18 is electrically connected to the second terminal of diode D8 and the first terminal of capacitor C16. The second terminal of capacitor C16 is grounded. The fourth pin of the transformer T1 is electrically connected to the first terminal of capacitor C4, the corresponding terminal of optocoupler chip PC817, and the first terminal of diode D4 via diode D3 and resistor R15. The fifth pin of the transformer T1 is electrically connected to the second terminal of capacitor C4, the second terminal of capacitor C1, and the second terminal of resistor R2. The second terminal of diode D4 is electrically connected to the first terminal of capacitor C2 and the first terminal of diode D5. The second terminal of capacitor C2 is grounded, and the second terminal of diode D5 is electrically connected to the corresponding terminal of battery BAT1.

8. The household combustible gas detector according to claim 1, characterized in that, The gas detection circuit includes a combustible gas sensor, and the corresponding terminal of the combustible gas sensor is electrically connected to the corresponding terminal of the MCU.

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