A dual sensor channel and display domestic gas detector

Abstract

The utility model belongs to the technical field of detector, concretely is a kind of domestic gas detector with double-sensor channel and display.A kind of domestic gas detector with double-sensor channel and display, including upper shell, lower shell, circuit board and display screen;The display screen is arranged on the circuit board;The upper shell is provided with opening, and the circuit board is arranged on the lower shell, and the upper shell is matched with the lower shell;Display screen is located at the opening of upper shell;The circuit board includes power supply circuit, acquisition circuit and main control circuit;The power supply circuit is connected with acquisition circuit and main control circuit respectively;The acquisition circuit is connected with main control circuit;Acquisition circuit includes first sensor and second sensor.The utility model is provided with two sensors, and double sensor can monitor gas in real time, which helps to ensure the accuracy of detection results.The utility model is provided with display screen, and the display screen can display the concentration value of double-channel gas in real time and linearly.

Description

Technical Field

[0001] This invention belongs to the field of detector technology, specifically a household gas detector with dual sensor channels and display. Background Technology

[0002] Gas detectors are critical safety devices in industrial production, household life, and public places, enabling timely monitoring of flammable gas leaks and preventing accidents. Natural gas, a commonly used energy source, is particularly vulnerable to fires and explosions when leaked; carbon monoxide, a colorless and odorless but highly hazardous toxic gas, is also a significant safety concern. Real-time monitoring of both is essential for safety protection.

[0003] In existing technologies, most gas detectors are equipped with only a single sensor, enabling them to monitor only one type of gas. Simultaneous monitoring of natural gas and carbon monoxide requires multiple detectors, increasing equipment costs and installation space. Furthermore, differences in response from different devices can hinder data analysis, posing safety risks. Moreover, existing gas detectors lack displays, making it impossible to visually indicate gas concentrations.

[0004] Therefore, existing gas detectors are insufficient in terms of multi-gas simultaneous monitoring and display capabilities, making it difficult to meet the safety monitoring needs in complex scenarios. There is an urgent need for a gas detector that integrates dual sensors and has display functions to improve the accuracy and convenience of monitoring. Utility Model Content

[0005] To address the aforementioned problems, the purpose of this invention is to provide a household gas detector with dual sensor channels and a display.

[0006] This utility model discloses a household gas detector with dual sensor channels and a display, comprising an upper shell, a lower shell, a circuit board, and a display screen; the display screen is mounted on the circuit board; the upper shell has an opening, and the circuit board is mounted on the lower shell, with the upper and lower shells fitting together; the display screen is located at the opening of the upper shell; the circuit board includes a power supply circuit, a data acquisition circuit, and a main control circuit; the power supply circuit is connected to both the data acquisition circuit and the main control circuit; the data acquisition circuit is connected to the main control circuit; the data acquisition circuit includes a first sensor and a second sensor.

[0007] Furthermore, the power supply circuit includes a primary power supply circuit, a secondary power supply circuit, and a tertiary power supply circuit; the output of the primary power supply circuit is denoted as the first output; the output of the secondary power supply circuit is denoted as the second output; and the output of the tertiary power supply circuit is denoted as the third output; the first output is connected to the secondary power supply circuit; and the third output is connected to the tertiary power supply circuit.

[0008] Furthermore, the primary power supply circuit includes interface J4, rectifier bridge D5, main power chip U4, transformer T1, and inductor L1; the input of interface J4 is the external AC voltage, and the output of interface J4 is connected to the input of rectifier bridge D5; the output of the rectifier bridge, after passing through main power chip U4, transformer T1, and inductor L1, forms the first output.

[0009] Furthermore, the secondary power supply circuit includes a secondary power supply chip U5, resistors R37, R38, R39, and R40, capacitor C20, and inductor L2.

[0010] Pin 1 of the secondary power chip U5 is connected to ground; pin 3 of the secondary power chip U5 is connected to the first output; pin 5 of the secondary power chip U5 is connected to pin 3 through resistor R37; pin 6 of the secondary power chip U5 is connected to one end of capacitor C20, and the other end of capacitor C20 is connected to one end of inductor L2, the other end of inductor L2 being the second output; pin 2 of the secondary power chip U5 is connected to the other end of capacitor C20; pin 4 of the secondary power chip U5 is connected to one end of resistor R38, and the other end of resistor R38 is connected to the other end of inductor L2 through resistor R39; the other end of resistor R38 is grounded through resistor R40.

[0011] Furthermore, the three-stage power supply circuit includes a three-stage power supply chip U6, resistors R41, R43, R44, and R45, capacitor C25, and inductor L3.

[0012] Pin 1 of the three-stage power supply chip U6 is connected to ground; pin 3 of the three-stage power supply chip U6 is connected to the first output; pin 5 of the three-stage power supply chip U6 is connected to pin 3 through resistor R41; pin 6 of the three-stage power supply chip U6 is connected to one end of capacitor C25, and the other end of capacitor C25 is connected to one end of inductor L3, the other end of inductor L3 is the third output; the third output is 3.8V; pin 2 of the three-stage power supply chip U6 is connected to the other end of capacitor C25; pin 4 of the three-stage power supply chip U6 is connected to one end of resistor R43, and the other end of resistor R43 is connected to the other end of inductor L3 through resistor R44; the other end of resistor R43 is grounded through resistor R45; the output of the other end of inductor L3 through diode D9 is the fourth output VCC1; the output of the other end of inductor L3 through diode D1 is the fifth output VCC.

[0013] Furthermore, the main control circuit includes an MCU chip U2, a display driver chip U1, a diode D17, and a diode D18;

[0014] Pin 2 of MCU chip U2 is connected to pin 2 of display driver chip U1 via diode D17; pin 3 of MCU chip U2 is connected to pin 3 of display driver chip U1 via diode D18; pin 1 of display driver chip U1 is connected to pin 12 of the display screen; pin 4 of display driver chip U1 is grounded; pin 5 of display driver chip U1 is connected to pin 9 of the display screen; pin 6 of display driver chip U1 is connected to pin 8 of the display screen; pin 7 of display driver chip U1 is connected to pin 6 of the display screen; pin 8 of display driver chip U1 is connected to pin 11 of the display screen; pin 9 of display driver chip U1 is connected to pin 7 of the display screen; pin 10 of display driver chip U1 is connected to the third output; pin 11 of display driver chip U1 is connected to pin 4 of the display screen; pin 12 of display driver chip U1 is connected to pin 2 of the display screen; pin 13 of display driver chip U1 is connected to pin 1 of the display screen; pin 14 of display driver chip U1 is connected to pin 10 of the display screen; pin 15 of display driver chip U1 is connected to pin 5 of the display screen; pin 16 of display driver chip U1 is connected to pin 3 of the display screen.

[0015] Furthermore, the circuit board also includes an alarm circuit, which includes a buzzer B1, resistors R16 and R19, and transistor Q6.

[0016] The positive terminal of buzzer B1 is connected to the fifth output VCC through resistor R16; the negative terminal of buzzer B1 is connected to pin 3 of transistor Q6; pin 2 of transistor Q6 is grounded, and pin 1 of transistor Q6 is connected to pin 28 of MCU chip U2 through resistor R19.

[0017] Furthermore, the first sensor is a natural gas sensor, and the second sensor is a carbon monoxide sensor; the first output pin of the natural gas sensor is connected to pin 10 of the MCU chip U2; the second output pin of the natural gas sensor is connected to pin 11 of the MCU chip U2 through resistor R64; and the carbon monoxide sensor is connected to pin 14 of the MCU chip U2 through operational amplifier U9.

[0018] Furthermore, it also includes a back plate; the back plate is disposed below the lower shell.

[0019] The beneficial effects of this utility model are:

[0020] This invention relates to a gas detector equipped with two sensors (a natural gas sensor and a carbon monoxide sensor). The dual sensors enable real-time monitoring of the gas, helping to ensure accurate detection results. The invention also includes a display screen that can linearly display the concentration values ​​of the gas from both channels in real time. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the present utility model. Figure 1 ;

[0023] Figure 2 This is a schematic diagram of the present utility model. Figure 2 ;

[0024] Figure 3 This is a schematic diagram of the present utility model. Figure 3 ;

[0025] Figure 4 This is a schematic diagram of the power supply circuit of this utility model;

[0026] Figure 5 This is a schematic diagram of the main control circuit of this utility model;

[0027] Figure 6 This is a schematic diagram of the data acquisition circuit of this utility model.

[0028] Explanation of reference numerals in the attached figures

[0029] 1. Faceplate, 2. Top shell, 3. Circuit board, 4. Bottom shell, 5. Back plate, 6. Display screen. Detailed Implementation

[0030] The technical solutions in the embodiments of this utility model are described clearly and completely below. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0031] The purpose of this invention is to provide a household gas detector with dual sensor channels and a display.

[0032] This utility model discloses a dual-sensor channel household gas detector with a display, comprising an upper shell 2, a lower shell 4, a circuit board 3, and a display screen 6, as shown below. Figures 1-2 As shown.

[0033] The display screen 6 is mounted on the circuit board 3; the upper shell 2 has an opening, and the circuit board 3 is mounted on the lower shell 4. The upper shell 2 and the lower shell 4 are fitted together (the upper shell 2 is snapped onto the lower shell 3 and then fixed by screws, so that the circuit board 3 is located within the cavity formed by the upper shell 2 and the lower shell 4). The display screen 6 is located at the opening of the upper shell 2. Preferably, the upper shell 2 has a transparent faceplate 1 at the opening, so that the detection values ​​displayed on the display screen 6 can be clearly seen, such as... Figures 1-3 As shown.

[0034] Circuit board 3 includes a power supply circuit, a data acquisition circuit, a main control circuit, and an alarm circuit, such as... Figures 4-6 As shown; the power supply circuit is connected to both the acquisition circuit and the main control circuit; the acquisition circuit is connected to the main control circuit; the acquisition circuit includes a first sensor and a second sensor. The display screen 6 is electrically connected to the main control circuit.

[0035] The power supply circuit includes a primary power supply circuit, a secondary power supply circuit, and a tertiary power supply circuit. The output of the primary power supply circuit is designated as the first output, which is 12V. The output of the secondary power supply circuit is designated as the second output, which is 5V. The output of the tertiary power supply circuit is designated as the third output, which is 3.8V. The first output is connected to the secondary power supply circuit; the third output is connected to the tertiary power supply circuit.

[0036] like Figure 4 As shown, the primary power supply circuit includes interface J4, rectifier bridge D5, main power chip U4, transformer T1, and inductor L1. The input of interface J4 is the external AC voltage, and the output of interface J4 is connected to the input of rectifier bridge D5. The output of the rectifier bridge is connected to the main power chip U4, transformer T1, and inductor L1 to form the first output.

[0037] Specifically, the two outputs of interface J4 are connected to the two inputs of rectifier bridge D5 respectively; the two outputs of rectifier bridge are connected through capacitor EC2.

[0038] The two outputs of the rectifier bridge are designated as the first output pin and the second output pin. The first output pin is connected to pin 4 of transformer T1. The second output pin is connected to pin 5 of transformer T1 via resistors R27 and R29, diode D8, and resistor R32. The second output pin is also connected to pin 1 of transformer T1. Pin 3 of transformer T1 is connected to pin 1 of transformer T1 via resistor R30, diode D7, and resistor R28.

[0039] Pin 1 of the main power supply chip U4 is connected to the first output pin of rectifier bridge D5 through capacitor EC5. Pin 2 of the main power supply chip U4 is connected to pin 5 of transformer T1 through resistor R33. Pin 4 of the main power supply chip U4 is connected to the first output pin of rectifier bridge D5 through resistor R35; pin 4 of the main power supply chip U4 is also connected to the first output pin of rectifier bridge D5 through resistor R36. Pin 9 of transformer T1 is grounded, and pin 10 of transformer T1 outputs the first output through diode D6 and inductor L1. The first output is 12V.

[0040] The secondary power supply circuit includes a secondary power supply chip U5, resistors R37, R38, R39, and R40, capacitor C20, and inductor L2. Pin 1 of the secondary power supply chip U5 is connected to ground. Pin 3 of the secondary power supply chip U5 is connected to the first output. Pin 5 of the secondary power supply chip U5 is connected to pin 3 through resistor R37. Pin 6 of the secondary power supply chip U5 is connected to one end of capacitor C20, and the other end of capacitor C20 is connected to one end of inductor L2. The other end of inductor L2 is the second output, which is 5V. Pin 2 of the secondary power supply chip U5 is connected to the other end of capacitor C20. Pin 4 of the secondary power supply chip U5 is connected to one end of resistor R38, and the other end of resistor R38 is connected to the other end of inductor L2 through resistor R39. The other end of resistor R38 is grounded through resistor R40. The other end of inductor L2 is grounded through capacitors C23, C21, C23, and C24.

[0041] The three-stage power supply circuit includes a three-stage power supply chip U6, resistors R41, R43, R44, and R45, capacitor C25, and inductor L3. Pin 1 of the three-stage power supply chip U6 is connected to ground; pin 3 of the three-stage power supply chip U6 is connected to the first output; pin 5 of the three-stage power supply chip U6 is connected to pin 3 through resistor R41; pin 6 of the three-stage power supply chip U6 is connected to one end of capacitor C25, and the other end of capacitor C25 is connected to one end of inductor L3, the other end of inductor L3 being the third output; the third output is 3.8V; pin 2 of the three-stage power supply chip U6 is connected to the other end of capacitor C25; pin 4 of the three-stage power supply chip U6 is connected to one end of resistor R43, and the other end of resistor R43 is connected to the other end of inductor L3 through resistor R44; the other end of resistor R43 is grounded through resistor R45. The other end of inductor L3 outputs the fourth output VCC1 through diode D9; the other end of inductor L3 outputs the fifth output VCC through diode D1, as shown below. Figure 4 As shown.

[0042] like Figure 5 As shown, Figure 5The main power chip U4 is the main control chip that converts AC to DC. After the AC voltage is input through interface J4, it can be converted into 12V DC (DC12V) for use by the subsequent circuits. The secondary power chip U5 and the tertiary power chip U6 have DC step-down functions, which reduce DC12V to the voltage values ​​of 5V (second output) and 3.8V (third output) used by the subsequent circuits. The 3.8V is further divided into VCC (fourth output) and VCC1 (fifth output) through diodes to supply the main control circuit and other circuits. The voltage conversion of each stage is completed automatically after power-on and is not controlled by the enable terminal.

[0043] The main control circuit includes an MCU chip U2, a display driver chip U1, diodes D17 and D18. Pin 2 of the MCU chip U2 is connected to pin 2 of the display driver chip U1 via diode D17; pin 3 of the MCU chip U2 is connected to pin 3 of the display driver chip U1 via diode D18; pin 1 of the display driver chip U1 is connected to pin 12 of the display screen 6; pin 4 of the display driver chip U1 is grounded; pin 5 of the display driver chip U1 is connected to pin 9 of the display screen 6; pin 6 of the display driver chip U1 is connected to pin 8 of the display screen 6; pin 7 of the display driver chip U1 is connected to pin 6 of the display screen 6; pin 8 of the display driver chip U1 is connected to pin 6 of the display screen 6. Pin 11 of the display driver chip U1 is connected to pin 7 of the display screen 6; pin 10 of the display driver chip U1 is connected to the third output; pin 11 of the display driver chip U1 is connected to pin 4 of the display screen 6; pin 12 of the display driver chip U1 is connected to pin 2 of the display screen 6; pin 13 of the display driver chip U1 is connected to pin 1 of the display screen 6; pin 14 of the display driver chip U1 is connected to pin 10 of the display screen 6; pin 15 of the display driver chip U1 is connected to pin 5 of the display screen 6; pin 16 of the display driver chip U1 is connected to pin 3 of the display screen 6.

[0044] The alarm circuit includes a buzzer B1, resistors R16 and R19, and a transistor Q6. The positive terminal of buzzer B1 is connected to the fifth output VCC through resistor R16; the negative terminal of buzzer B1 is connected to pin 3 of transistor Q6; pin 2 of transistor Q6 is grounded, and pin 1 of transistor Q6 is connected to pin 28 of MCU chip U2 through resistor R19. Figure 5 As shown.

[0045] like Figure 5As shown, circuit board 3 also includes a solenoid valve drive circuit, a power-down detection circuit, a digital output circuit, and an alarm time recording circuit. The solenoid valve drive circuit is connected to pin 30 of MCU chip U2, the power-down detection circuit is connected to pin 8 of MCU chip U2, the digital output circuit is connected to pin 29 of MCU chip U2, and the alarm time recording circuit is connected to pins 2 and 3 of MCU chip U2. The solenoid valve drive circuit can be used to control the emergency shut-off valve on the natural gas pipeline; when the concentration exceeds the standard, it can control the valve to close. The digital output circuit can be connected to control an external exhaust fan; when the natural gas concentration exceeds the standard, the exhaust fan can be started through the digital output circuit.

[0046] The data acquisition circuit includes a first sensor and a second sensor. The first sensor is a natural gas sensor, and the second sensor is a carbon monoxide sensor. The first output pin of the natural gas sensor is connected to pin 10 of the MCU chip U2. The second output pin of the natural gas sensor is connected to pin 11 of the MCU chip U2 through resistor R64. The carbon monoxide sensor is connected to pin 14 of the MCU chip U2 through operational amplifier U9.

[0047] Specifically, such as Figure 6 As shown, SEN1 is a natural gas sensor. The natural gas sensor outputs a voltage value through sampling resistor R64. Therefore, the output SENSOR2 of the natural gas sensor is connected to pin 11 of MCU chip U2. SENSOR1 is a carbon monoxide sensor. The carbon monoxide sensor must be amplified by the operational amplifier U9 before its output SENSOR1 can be connected to pin 14 of MCU chip U2.

[0048] The MCU chip U2 collects signals from the natural gas sensor and the carbon monoxide sensor. After calculation, it displays the corresponding natural gas concentration value and carbon monoxide concentration value on the display screen 6 (LED1) through the display driver chip U1. The MCU chip U2 compares the calculated real-time concentration value with the preset alarm value. If the real-time concentration value reaches the alarm value, the MCU chip U2 drives the buzzer B1 to sound an alarm, drives the display screen 6 to indicate an alarm, and the switch output circuit outputs a switch signal, and records the alarm time (by reading the alarm time recording circuit U3).

[0049] The detector of this utility model is mainly used in household kitchens and places where gas hot water is used. It can monitor natural gas and gases such as carbon monoxide after incomplete combustion in real time. When the concentration exceeds the standard, it can issue an alarm and start the exhaust and shut off the gas emergency shut-off valve to effectively ensure the safety of household gas use.

[0050] Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

Claims

1. A household gas detector with dual sensor channels and display, characterized in that, The device includes an upper shell, a lower shell, a circuit board, and a display screen; the display screen is mounted on the circuit board; the upper shell has an opening, and the circuit board is mounted on the lower shell, with the upper and lower shells fitting together; the display screen is located at the opening of the upper shell; the circuit board includes a power supply circuit, a data acquisition circuit, and a main control circuit; the power supply circuit is connected to both the data acquisition circuit and the main control circuit; the data acquisition circuit is connected to the main control circuit; the data acquisition circuit includes a first sensor and a second sensor.

2. A household gas detector with dual sensor channels and display according to claim 1, characterized in that, The power supply circuit includes a primary power supply circuit, a secondary power supply circuit, and a tertiary power supply circuit; the output of the primary power supply circuit is denoted as the first output; the output of the secondary power supply circuit is denoted as the second output; and the output of the tertiary power supply circuit is denoted as the third output; the first output is connected to the secondary power supply circuit. The first output is connected to a three-stage power supply circuit.

3. A household gas detector with dual sensor channels and display according to claim 2, characterized in that, The primary power supply circuit includes interface J4, rectifier bridge D5, main power chip U4, transformer T1, and inductor L1. The input of interface J4 is the external AC voltage, and the output of interface J4 is connected to the input of rectifier bridge D5. The output of the rectifier bridge is formed by passing through main power chip U4, transformer T1, and inductor L1 to form the first output.

4. A household gas detector with dual sensor channels and display according to claim 3, characterized in that, The secondary power supply circuit includes a secondary power supply chip U5, resistors R37, R38, R39, and R40, capacitor C20, and inductor L2. Pin 1 of the secondary power chip U5 is connected to ground; pin 3 of the secondary power chip U5 is connected to the first output; pin 5 of the secondary power chip U5 is connected to pin 3 through resistor R37; pin 6 of the secondary power chip U5 is connected to one end of capacitor C20, and the other end of capacitor C20 is connected to one end of inductor L2, the other end of inductor L2 being the second output; pin 2 of the secondary power chip U5 is connected to the other end of capacitor C20; pin 4 of the secondary power chip U5 is connected to one end of resistor R38, and the other end of resistor R38 is connected to the other end of inductor L2 through resistor R39; the other end of resistor R38 is grounded through resistor R40.

5. A household gas detector with dual sensor channels and display according to claim 3, characterized in that, The three-level power supply circuit includes a three-level power supply chip U6, resistors R41, R43, R44, and R45, capacitor C25, and inductor L3. Pin 1 of the three-stage power supply chip U6 is connected to ground; pin 3 of the three-stage power supply chip U6 is connected to the first output; pin 5 of the three-stage power supply chip U6 is connected to pin 3 through resistor R41; pin 6 of the three-stage power supply chip U6 is connected to one end of capacitor C25, and the other end of capacitor C25 is connected to one end of inductor L3, the other end of inductor L3 is the third output; the third output is 3.8V; pin 2 of the three-stage power supply chip U6 is connected to the other end of capacitor C25; pin 4 of the three-stage power supply chip U6 is connected to one end of resistor R43, and the other end of resistor R43 is connected to the other end of inductor L3 through resistor R44; the other end of resistor R43 is grounded through resistor R45; the output of the other end of inductor L3 through diode D9 is designated as the fourth output VCC1; the output of the other end of inductor L3 through diode D1 is designated as the fifth output VCC.

6. A household gas detector with dual sensor channels and display according to claim 5, characterized in that, The main control circuit includes MCU chip U2, display driver chip U1, diode D17, and diode D18; Pin 2 of MCU chip U2 is connected to pin 2 of display driver chip U1 via diode D17; pin 3 of MCU chip U2 is connected to pin 3 of display driver chip U1 via diode D18; pin 1 of display driver chip U1 is connected to pin 12 of the display screen; pin 4 of display driver chip U1 is grounded; pin 5 of display driver chip U1 is connected to pin 9 of the display screen; pin 6 of display driver chip U1 is connected to pin 8 of the display screen; pin 7 of display driver chip U1 is connected to pin 6 of the display screen; pin 8 of display driver chip U1 is connected to pin 11 of the display screen; pin 9 of display driver chip U1 is connected to pin 7 of the display screen; pin 10 of display driver chip U1 is connected to the third output; pin 11 of display driver chip U1 is connected to pin 4 of the display screen; pin 12 of display driver chip U1 is connected to pin 2 of the display screen; pin 13 of display driver chip U1 is connected to pin 1 of the display screen; pin 14 of display driver chip U1 is connected to pin 10 of the display screen; pin 15 of display driver chip U1 is connected to pin 5 of the display screen; pin 16 of display driver chip U1 is connected to pin 3 of the display screen.

7. A household gas detector with dual sensor channels and display according to claim 6, characterized in that, The circuit board also includes an alarm circuit, which includes a buzzer B1, resistor R16, resistor R19, and transistor Q6. The positive terminal of buzzer B1 is connected to the fifth output VCC through resistor R16; the negative terminal of buzzer B1 is connected to pin 3 of transistor Q6; pin 2 of transistor Q6 is grounded, and pin 1 of transistor Q6 is connected to pin 28 of MCU chip U2 through resistor R19.

8. A household gas detector with dual sensor channels and display according to claim 6, characterized in that, The first sensor is a natural gas sensor, and the second sensor is a carbon monoxide sensor. The first output pin of the natural gas sensor is connected to pin 10 of the MCU chip U2. The second output pin of the natural gas sensor is connected to pin 11 of the MCU chip U2 through resistor R64. The carbon monoxide sensor is connected to pin 14 of the MCU chip U2 through operational amplifier U9.

9. A household gas detector with dual sensor channels and display according to claim 1, characterized in that, It also includes a back plate; the back plate is disposed below the lower shell.

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