Composite low-power-consumption combustible gas sensor system

Abstract

The invention relates to a composite low-power-consumption combustible gas sensor system, which comprises a sensor PCBA2, and the sensor PCBA2 comprises an MCU main control circuit used for carrying out data analysis on a sensor; the MCU power supply circuit is used for providing a stable power supply for the MCU circuit; the semiconductor sensor power supply circuit provides a stable power supply for the semiconductor sensor; the semiconductor sensor signal conditioning circuit is used for conditioning a semiconductor sensor signal into a voltage signal which can be effectively measured; the catalytic sensor power supply circuit provides a stable power supply for the catalytic sensor; and the catalytic sensor signal conditioning circuit is used for conditioning a catalytic sensor signal into a voltage signal which can be effectively measured. With the adoption of the composite low-power-consumption combustible gas sensor system, the requirements of detection precision and low power consumption are mainly met, battery power supply and concentration display can be realized at low cost, and the power consumption of a product can be effectively reduced, so that a combustible gas detector powered by a battery can be realized at relatively low cost; the blank of the scheme in the current market is filled.

Description

Technical Field

[0001] The present invention relates to the field of gas detection, in particular to the field of battery-powered combustible gas sensors, and specifically refers to a composite low-power consumption combustible gas sensor system. Background Art

[0002] At present, the combustible gas sensors on the market are mainly divided into semiconductor principle, catalytic principle, infrared principle, laser principle, etc. The only low-power combustible gas sensors that can be powered by batteries are semiconductor principle and infrared principle. Among them, the infrared principle low-power combustible gas sensor is very expensive and cannot be used in cost-constrained scenarios. The semiconductor principle low-power combustible gas sensor has poor linearity and a small measurable concentration range, and cannot accurately display the combustible gas concentration and display the full range.

[0003] The current infrared principle low-power combustible gas sensors are expensive and have complex manufacturing processes, making them unsuitable for cost-constrained application scenarios.

[0004] Semiconductor low power consumption combustible gas sensors cannot accurately display the concentration of combustible gas. Semiconductor low power consumption combustible gas sensors cannot measure high concentration combustible gas.

[0005] Catalytic combustible gas sensors have high power consumption and cannot be used in low-power scenarios. Summary of the invention

[0006] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a composite low-power combustible gas sensor system that meets the requirements of high accuracy, a large measurable concentration range, and a relatively wide range of applications.

[0007] In order to achieve the above object, the composite low-power consumption combustible gas sensor system of the present invention is as follows:

[0008] The main feature of the composite low-power flammable gas sensor system is that the system includes a sensor PCBA2, and the sensor PCBA2 includes:

[0009] MCU main control circuit, used for data analysis, logic control and communication functions of the sensor;

[0010] MCU power supply circuit, connected to the MCU main control circuit, used to provide stable power supply for the MCU circuit;

[0011] A semiconductor sensor power supply circuit is connected to the MCU main control circuit and is used to provide a stable power supply for the semiconductor sensor;

[0012] A semiconductor sensor signal conditioning circuit, connected to the semiconductor sensor power supply circuit, for conditioning the semiconductor sensor signal into a voltage signal that can be effectively measured;

[0013] A catalytic sensor power supply circuit, connected to the MCU main control circuit, for providing a stable power supply for the catalytic sensor;

[0014] A catalytic sensor signal conditioning circuit, connected to the catalytic sensor power supply circuit, for conditioning the catalytic sensor signal into a voltage signal that can be effectively measured;

[0015] The UART or IIC communication interface circuit is connected to the MCU main control circuit and is used to obtain power from the outside and to communicate with the outside digitally.

[0016] Preferably, the semiconductor sensor signal conditioning circuit includes a drive circuit and a detection circuit, both of which are connected to the semiconductor sensor power supply circuit. The drive circuit heats the inside of the sensor to an optimal temperature, and the detection circuit converts the resistance change of the sensitive material into a voltage change through resistance voltage division, and converts the voltage analog signal into a digital signal through the single-chip microcomputer ADC for analyzing and calculating the gas concentration value.

[0017] Preferably, the catalytic sensor signal conditioning circuit converts the resistance change of the detection element and the compensation element inside the catalytic sensor into a voltage difference through a Wheatstone bridge, adjusts it into a suitable voltage value through an instrument amplifier circuit, and converts the voltage value into a digital value through the ADC inside the microcontroller.

[0018] Preferably, if the system is in a gas-free or low-concentration environment, the semiconductor sensor power circuit works; if the system is in a high-concentration environment, the catalytic sensor power circuit works.

[0019] Preferably, the system is used to detect combustible gas leakage and accurately display the gas concentration.

[0020] Preferably, the system also includes a sensor base plate, a gas collecting sponge, a powder sintered explosion-proof net and a sensor metal shell, the gas collecting sponge has two circular holes, the sensor PCBA passes through the circular holes on the gas collecting sponge and is installed on the gas collecting sponge, the powder sintered explosion-proof net is installed below the gas collecting sponge, the sensor base plate is installed on the top of the sensor metal shell, and the sensor PCBA, gas collecting sponge and powder sintered explosion-proof net are all placed in the sensor metal shell.

[0021] Preferably, the system for detecting combustible gas leakage specifically comprises the following steps:

[0022] (1) Start the catalytic sensor;

[0023] (2) Determine whether the gas concentration is lower than a set threshold value C1, where C1 is the upper limit of the semiconductor sensor range. If yes, proceed to step (3); otherwise, turn off the semiconductor sensor;

[0024] (3) Determine whether the gas concentration is lower than the set threshold value C2, where C2 is the lower limit for starting the catalytic sensor. If so, turn off the catalytic sensor and update the semiconductor sensor parameter A2; otherwise, proceed to step (4);

[0025] (4) Start the semiconductor sensor;

[0026] (5) Determine whether the change in the semiconductor detection value is lower than a set value A1, where A1 is a semiconductor sensor parameter. If yes, proceed to step (6); otherwise, proceed to step (1);

[0027] (6) Determine whether the change in the semiconductor detection value is lower than the semiconductor sensor parameter A2, where A2 is the semiconductor sensor parameter. If so, proceed to step (5); otherwise, proceed to step (1).

[0028] The composite low-power combustible gas sensor system of the present invention mainly solves the detection accuracy and low power consumption requirements. It can be battery-powered and display concentration at low cost, which can effectively reduce the power consumption of the product, so that the battery-powered combustible gas detector can be realized at a relatively low cost, filling the gap in this solution in the current market. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the structure of the composite low-power consumption combustible gas sensor system of the present invention.

[0030] Figure 2 It is a schematic structural diagram of the sensor PCBA of the composite low-power consumption combustible gas sensor system of the present invention.

[0031] Figure 3 The schematic diagram of the sensor working process of the composite low-power consumption combustible gas sensor system of the present invention is shown in FIG.

[0032] Figure 4 The figure is a schematic diagram of a specific working process of the composite low-power flammable gas sensor system of the present invention.

[0033] Reference numerals:

[0034] 1 Sensor base plate

[0035] 2 Sensor PCBA

[0036] 3 Gas Collection Sponge

[0037] 4 Powder sintered explosion-proof net

[0038] 5 Sensor metal housing DETAILED DESCRIPTION

[0039] In order to more clearly describe the technical content of the present invention, further description is given below in conjunction with specific embodiments.

[0040] The composite low-power consumption combustible gas sensor system of the present invention includes a sensor PCBA2, wherein the sensor PCBA2 includes:

[0041] MCU main control circuit, used for data analysis, logic control and communication functions of the sensor;

[0042] MCU power supply circuit, connected to the MCU main control circuit, used to provide stable power supply for the MCU circuit;

[0043] A semiconductor sensor power supply circuit is connected to the MCU main control circuit and is used to provide a stable power supply for the semiconductor sensor;

[0044] A semiconductor sensor signal conditioning circuit, connected to the semiconductor sensor power supply circuit, for conditioning the semiconductor sensor signal into a voltage signal that can be effectively measured;

[0045] A catalytic sensor power supply circuit, connected to the MCU main control circuit, for providing a stable power supply for the catalytic sensor;

[0046] A catalytic sensor signal conditioning circuit, connected to the catalytic sensor power supply circuit, for conditioning the catalytic sensor signal into a voltage signal that can be effectively measured;

[0047] The UART or IIC communication interface circuit is connected to the MCU main control circuit and is used to obtain power from the outside and to communicate with the outside digitally.

[0048] As a preferred embodiment of the present invention, the semiconductor sensor signal conditioning circuit includes a drive circuit and a detection circuit, both of which are connected to the semiconductor sensor power supply circuit. The drive circuit heats the inside of the sensor to an optimal temperature. The detection circuit converts the resistance change of the sensitive material into a voltage change through resistance voltage division, and converts the voltage analog signal into a digital signal through the single-chip microcomputer ADC for analyzing and calculating the gas concentration value.

[0049] As a preferred embodiment of the present invention, the catalytic sensor signal conditioning circuit converts the resistance changes of the detection element and the compensation element inside the catalytic sensor into a voltage difference through a Wheatstone bridge, adjusts it into a suitable voltage value through an instrument amplifier circuit, and converts the voltage value into a digital quantity through the ADC inside the microcontroller.

[0050] As a preferred embodiment of the present invention, if the system is in a low-concentration environment without gas leakage, the semiconductor sensor power supply circuit works; if it is in a high-concentration environment, the catalytic sensor power supply circuit works.

[0051] As a preferred embodiment of the present invention, the system is used to detect the leakage of combustible gas and accurately display the gas concentration.

[0052] As a preferred embodiment of the present invention, the system also includes a sensor base plate 1, an air collecting sponge 3, a powder sintered explosion-proof net 4 and a sensor metal shell 5. The air collecting sponge 3 has two circular holes. The sensor PCBA2 passes through the circular holes on the air collecting sponge 3 and is installed on the air collecting sponge 3. The powder sintered explosion-proof net 4 is installed below the air collecting sponge 3. The sensor base plate 1 is installed on the top of the sensor metal shell 5. The sensor PCBA2, air collecting sponge 3 and powder sintered explosion-proof net 4 are all placed in the sensor metal shell 5.

[0053] As a preferred embodiment of the present invention, the system for detecting combustible gas leakage specifically comprises the following steps:

[0054] (1) Start the catalytic sensor;

[0055] (2) Determine whether the gas concentration is lower than a set threshold value C1, where C1 is the upper limit of the semiconductor sensor range. If yes, proceed to step (3); otherwise, turn off the semiconductor sensor;

[0056] (3) Determine whether the gas concentration is lower than the set threshold value C2, where C2 is the lower limit for starting the catalytic sensor. If so, turn off the catalytic sensor and update the semiconductor sensor parameter A2; otherwise, proceed to step (4);

[0057] (4) Start the semiconductor sensor;

[0058] (5) Determine whether the change in the semiconductor detection value is lower than a set value A1, where A1 is a semiconductor sensor parameter. If yes, proceed to step (6); otherwise, proceed to step (1);

[0059] (6) Determine whether the change in the semiconductor detection value is lower than the semiconductor sensor parameter A2, where A2 is the semiconductor sensor parameter. If so, proceed to step (5); otherwise, proceed to step (1).

[0060] Among them, C1 is the upper limit of the semiconductor sensor range (for example, it can be set to 20% LEL), and the threshold C2 is the lower limit of the catalytic sensor startup (for example, it can be set to 5% LEL). Set value A1 and set value A2 are semiconductor sensor parameters, and A1 is the change startup condition, that is, the semiconductor sensor detects a sudden change in the gas concentration in the environment, and the change reaches A1 to infer that a gas leak may occur, that is, the catalytic sensor is started for confirmation. A2 is the concentration condition, that is, when a slow leak occurs, the semiconductor sensor A1 detection condition fails, but when the set concentration value A2 is reached, the catalytic sensor is started for accurate detection.

[0061] In a specific embodiment of the present invention, a composite low-power gas sensor is provided by integrating the low-power consumption characteristics of a semiconductor combustible gas sensor with the high-precision characteristics of a catalytic combustible gas sensor.

[0062] The sensor structure mainly includes five components, including a sensor base plate 1, a sensor PCBA 2, a gas collecting sponge 3, a powder sintered explosion-proof net 4 and a sensor metal shell 5. The sensor PCBA 2 includes a sensor main board PCBA and a sensor signal board PCBA.

[0063] The sensor circuit is mainly divided into the following parts:

[0064] MCU power circuit, responsible for providing stable power to the MCU circuit;

[0065] MCU main control circuit, responsible for sensor data analysis, logic control and communication functions;

[0066] Semiconductor sensor power supply circuit, responsible for providing stable power supply for semiconductor sensors;

[0067] Semiconductor sensor conditioning circuit, responsible for conditioning the semiconductor sensor signal into a voltage signal that can be effectively measured;

[0068] Catalytic sensor power supply circuit, responsible for providing stable power supply for the catalytic sensor;

[0069] A catalytic sensor signal conditioning circuit is responsible for conditioning the catalytic sensor signal into a voltage signal that can be effectively measured;

[0070] The UART / IIC communication interface circuit is responsible for obtaining power from the outside and communicating with the outside digitally.

[0071] This solution has two main technical features:

[0072] Dimension 1: Sensitivity and accuracy. Combining the characteristics of semiconductor sensors that are sensitive but not very accurate, and catalytic sensors that are highly accurate, semiconductor sensors work in environments with no gas leakage or low concentrations. In environments with higher concentrations, catalytic sensors need to be turned on to achieve accurate measurement of gas concentrations.

[0073] Dimension 2: Power consumption. In the actual life cycle of the product, most of the time there is no gas leakage. In this environment, using low-power semiconductor sensors can effectively reduce product power consumption. In the rare case of gas leakage, using higher-power catalytic sensors can accurately measure the concentration of combustible gas. The overall power consumption of the product will be very low, and it can be effectively used in portable and battery-powered combustible gas products.

[0074] The biggest innovation of this case is that it combines the characteristics of two sensors with different principles and characteristics. In actual use, most of the time there is no flammable gas leakage environment, and the ultra-low power semiconductor sensor is mainly used for detection in this environment. In the case of gas leakage, the catalytic sensor with slightly higher power consumption will be activated to achieve accurate measurement.

[0075] The specific implementation scheme of this embodiment can refer to the relevant description in the above embodiment, which will not be repeated here.

[0076] It can be understood that the same or similar parts of the above embodiments can be referenced to each other, and the contents not described in detail in some embodiments can refer to the same or similar contents in other embodiments.

[0077] It should be noted that, in the description of the present invention, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, the meaning of "plurality" refers to at least two.

[0078] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0079] The composite low-power combustible gas sensor system of the present invention mainly solves the detection accuracy and low power consumption requirements. It can be battery-powered and display concentration at low cost, which can effectively reduce the power consumption of the product, so that the battery-powered combustible gas detector can be realized at a relatively low cost, filling the gap in this solution in the current market.

[0080] In this specification, the present invention has been described with reference to specific embodiments thereof. However, it is apparent that various modifications and variations may be made without departing from the spirit and scope of the present invention. Therefore, the specification and drawings should be regarded as illustrative rather than restrictive.

Claims

1. A composite low-power combustible gas sensor system, characterized in that: The system includes a sensor PCBA2, and the sensor PCBA2 includes: MCU main control circuit, used for data analysis, logic control and communication functions of the sensor; MCU power supply circuit, connected to the MCU main control circuit, used to provide stable power supply for the MCU circuit; A semiconductor sensor power supply circuit is connected to the MCU main control circuit and is used to provide a stable power supply for the semiconductor sensor; A semiconductor sensor signal conditioning circuit, connected to the semiconductor sensor power supply circuit, for conditioning the semiconductor sensor signal into a voltage signal that can be effectively measured; A catalytic sensor power supply circuit, connected to the MCU main control circuit, for providing a stable power supply for the catalytic sensor; A catalytic sensor signal conditioning circuit, connected to the catalytic sensor power supply circuit, for conditioning the catalytic sensor signal into a voltage signal that can be effectively measured; The UART or IIC communication interface circuit is connected to the MCU main control circuit and is used to obtain power from the outside and to communicate with the outside digitally.

2. The composite low-power combustible gas sensor system according to claim 1, characterized in that: The semiconductor sensor signal conditioning circuit includes a drive circuit and a detection circuit, both of which are connected to the semiconductor sensor power supply circuit. The drive circuit heats the inside of the sensor to an optimal temperature. The detection circuit converts the resistance change of the sensitive material into a voltage change through resistance voltage division, and converts the voltage analog signal into a digital signal through the single-chip microcomputer ADC for analyzing and calculating the gas concentration value.

3. The composite low-power combustible gas sensor system according to claim 1, characterized in that: The catalytic sensor signal conditioning circuit converts the resistance change of the detection element and the compensation element inside the catalytic sensor into a voltage difference through a Wheatstone bridge, adjusts it into a suitable voltage value through an instrument amplifier circuit, and converts the voltage value into a digital value through the ADC inside the microcontroller.

4. The composite low-power consumption combustible gas sensor system according to claim 1, characterized in that: If the system is in a gas-free or low-concentration environment, the semiconductor sensor power supply circuit works; if it is in a high-concentration environment, the catalytic sensor power supply circuit works.

5. The composite low-power consumption combustible gas sensor system according to claim 1, characterized in that: The system is used to detect the leakage of combustible gas and accurately display the gas concentration.

6. The composite low-power consumption combustible gas sensor system according to claim 1, characterized in that: The system also includes a sensor base plate, a gas collecting sponge, a powder sintered explosion-proof net and a sensor metal shell. The gas collecting sponge has two circular holes. The sensor PCBA passes through the circular holes on the gas collecting sponge and is installed on the gas collecting sponge. The powder sintered explosion-proof net is installed below the gas collecting sponge. The sensor base plate is installed on the top of the sensor metal shell. The sensor PCBA, gas collecting sponge and powder sintered explosion-proof net are all placed in the sensor metal shell.

7. The composite low-power consumption combustible gas sensor system according to claim 1, characterized in that: The system for detecting combustible gas leakage specifically comprises the following steps: (1) Start the catalytic sensor; (2) Determine whether the gas concentration is lower than a set threshold value C1, where C1 is the upper limit of the semiconductor sensor range. If yes, proceed to step (3); otherwise, turn off the semiconductor sensor; (3) Determine whether the gas concentration is lower than the set threshold value C2, where C2 is the lower limit for starting the catalytic sensor. If so, turn off the catalytic sensor and update the semiconductor sensor parameter A2; otherwise, proceed to step (4); (4) Start the semiconductor sensor; (5) Determine whether the change in the semiconductor detection value is lower than a set value A1, where A1 is a semiconductor sensor parameter. If yes, proceed to step (6); otherwise, proceed to step (1); (6) Determine whether the change in the semiconductor detection value is lower than the semiconductor sensor parameter A2, where A2 is the semiconductor sensor parameter. If so, proceed to step (5); otherwise, proceed to step (1).

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