阅读说明：本技术 一种弥散型氧传感器及其控制方法 (Dispersion type oxygen sensor and control method thereof ) 是由 唐亮 于 2021-07-09 设计创作，主要内容包括：本发明提供了一种弥散型氧传感器及其控制方法,包括外壳、两超声波探头及控制模块,所述两超声波探头与所述控制模块电性连接；所述外壳包括两通道,包括第一通道与第二通道,所述第一通道与所述第二通道垂直设计,所述第二通道的内径大于所述第一通道的内径,所述两超声波探头分别堵塞在所述第一通道两端口上；所述第一通道与所述第二通道在垂直相交的位置连通；所述第二通道为开放式通道。根据超声波在空气中传播的速率不同的原理,通过实时的超声波传播速率换算出当前氧浓度,并通过实时的气压与温度补偿计算出当前氧环境的准确的氧浓度,使其适用于高原、平原环境的使用,同时提高测量的准确率。(The invention provides a dispersion type oxygen sensor and a control method thereof, wherein the dispersion type oxygen sensor comprises a shell, two ultrasonic probes and a control module, wherein the two ultrasonic probes are electrically connected with the control module; the shell comprises two channels, namely a first channel and a second channel, the first channel and the second channel are vertically designed, the inner diameter of the second channel is larger than that of the first channel, and the two ultrasonic probes are respectively plugged on two ports of the first channel; the first channel is communicated with the second channel at a position where the first channel and the second channel vertically intersect; the second channel is an open channel. According to the principle that the ultrasonic waves are transmitted at different rates in the air, the current oxygen concentration is converted through the real-time ultrasonic transmission rate, and the accurate oxygen concentration of the current oxygen environment is calculated through real-time air pressure and temperature compensation, so that the method is suitable for being used in plateau and plain environments, and meanwhile, the measurement accuracy is improved.)

1. A dispersion-type oxygen sensor, characterized by: the ultrasonic probe comprises a shell, two ultrasonic probes and a control module, wherein the two ultrasonic probes are electrically connected with the control module;

the shell comprises two channels, namely a first channel and a second channel, the first channel and the second channel are vertically designed, the inner diameter of the second channel is larger than that of the first channel, and the two ultrasonic probes are respectively plugged on two ports of the first channel;

the first channel is communicated with the second channel at a position where the first channel and the second channel vertically intersect;

the second channel is an open channel.

2. The dispersion-type oxygen sensor according to claim 1, wherein: the second channel is an air channel, and the first channel is an ultrasonic channel.

3. The dispersion-type oxygen sensor according to claim 1, wherein: the control module comprises a main control circuit, an air pressure detection module and a temperature detection module;

the air pressure detection module and the temperature detection module are electrically connected with the microprocessor circuit;

the master control circuit comprises a microprocessor circuit, a switching circuit, a filter circuit, an operational amplifier circuit and a comparison circuit;

the comparison circuit is electrically connected with the microprocessor circuit, and the switching circuit, the filter circuit, the operational amplifier circuit and the comparison circuit are sequentially connected.

4. The dispersion type oxygen sensor according to claim 3, wherein:

the microprocessor module comprises a microprocessor U1, and the model number of the microprocessor U1 is STM32F103C8T 6.

5. The dispersion type oxygen sensor according to claim 3, wherein:

the switching circuit comprises a chip U5, a chip U6, a chip U8 and a resistor R12;

the A1 port of the chip U5 is connected with a power supply V4, the VCC port of the chip U5 is connected with a power supply V1, the GND port and the A2 port of the chip U5 are grounded, and the ENB port of the chip U5 is connected with the PWM port of the microprocessor circuit;

the B port of the chip U5 is connected with the B port of the chip U6, and a resistor R12 is connected in series between the two ports;

the VCC port of the chip U6 is connected with a power supply V2, the A1 port of the chip U6 is connected with the A2 port of the chip U8, the A2 port of the chip U6 is connected with the A1 port of the chip U8, the ENB port of the chip U6 is connected with the ENB port of the chip U8 and is connected with the ENB port of the microprocessor circuit, the VCC port of the chip U8 is connected with the power supply V3, and the GND port of the chip U6 and the GND port of the chip U8 are grounded;

the models of the chip U5, the chip U6 and the chip U8 are the same as BL 1551.

6. The dispersion type oxygen sensor according to claim 3, wherein:

the filter circuit comprises a diode D7, a diode D8, a capacitor C12, a resistor R23 and a resistor R24, wherein the cathode of the diode D7 and the anode of the diode D8 are electrically connected with the resistor R24 respectively, one end of the resistor R23 is electrically connected with one end of the capacitor C12, and the anode of the diode D7 and the cathode of the diode D8 are grounded.

7. The dispersion type oxygen sensor according to claim 3, wherein:

the operational amplifier circuit comprises a chip U9, a resistor R13, a resistor R14, a resistor R29, a resistor R25, a resistor R26, a resistor R27, a resistor R28, a capacitor C11, a capacitor C13 and a capacitor C14;

the V-port of the chip U9 is grounded, the a + port of the chip U9 is connected to the filter circuit and the comparator circuit, two ends of the resistor R25 are respectively connected to the a-port of the chip U9 and the port of the chip a0, the port of the chip a0 is connected to one end of the resistor R13 and one end of the capacitor C11, the other end of the resistor R13 is grounded, the other end of the capacitor C11 is electrically connected to one end of the resistor R14, the V + port of the chip U9 is connected to the power supply V6, the B0 port of the chip U9 is connected to one end of the resistor R29 and the comparator circuit, the B-port of the chip U9 is respectively connected to one end of the resistor R26 and one end of the resistor R28, the B + port of the chip U9 is respectively connected to one end of the capacitor C13 and one end of the resistor R27, the other end of the capacitor C11 is connected to one end of the resistor R14, and the other end of the resistor R14 is respectively connected to one end of the capacitor C13 and one end of the resistor R29, One end of a capacitor C14, and the other end of the capacitor C14 is respectively connected with one end of a resistor R26 and one end of a resistor R27;

the chip U9 is model LMV 358.

8. The dispersion type oxygen sensor according to claim 3, wherein:

the comparison circuit comprises a chip U7, a resistor R16, a resistor R17, a resistor R15, a resistor R30, a resistor R32, a resistor R33, a resistor R34, a resistor R31 and a capacitor C15;

the OUT port of the chip U7 is connected with a CH _ Up port of a micro-processing circuit and one end of a resistor R16, the 1 IN-port of the chip U7 is respectively connected with one end of a resistor R15 and the 2IN + port of the chip U7, the 2 IN-port of the chip U7 is connected with a resistor R33 and a resistor R34, and the 2OUT port of the chip U7 is connected with one end of a resistor R17 and the CH _ Down port of the micro-processing circuit;

the resistor R30, the resistor R32, the resistor R33 and the resistor R34 are sequentially connected, the other end of the resistor R30 is connected with a power supply V10, one end of the resistor R31 is connected with the resistor R32, the resistor R33 and the capacitor C15, the other end of the capacitor C15 is grounded, and the other end of the resistor R34 is grounded;

the chip U7 is model LMV 393.

9. The dispersion type oxygen sensor according to claim 3, wherein:

the air pressure detection module comprises a chip U4, a capacitor C7, a resistor R8 and a resistor R9;

the chip U4 is characterized in that two ends of a VCC port and a GND port of the chip U4 are respectively connected with two ends of a capacitor C7, the VCC port of the chip U4 is connected with a power supply V1, the GND port of the chip U4 is grounded, the SDA port of the chip U4 is connected with one end of a resistor R8, the other end of the resistor R8 is connected with the power supply V1, the SCL port of the chip U4 is connected with one end of the resistor R9, the other end of the resistor R9 is connected with the power supply V1, the SDA port of the chip U4 is connected with the PA12 port of the chip U1, and the SCL port of the chip U4 is connected with the PA11 port of the chip U1;

the chip U12 model is MS 5637.

10. A control method of a dispersion type oxygen sensor is characterized in that: the method comprises the following steps:

step S1: the first channel and the second channel are filled with gas to be detected;

step S2: the microprocessor selects and excites the ultrasonic probe at one end to send out an ultrasonic signal, and the ultrasonic probe at the other end receives the ultrasonic signal to obtain the transmission time of the ultrasonic signal;

step S3: repeating the transmission of the ultrasonic signal in the gas for multiple times to obtain the real-time ultrasonic signal transmission time, and further converting the real-time oxygen concentration;

step S4: measuring a real-time air pressure value and a real-time temperature value through an air pressure detection module and a temperature detection module;

step S5: and (4) compensating and calculating the real-time oxygen concentration according to the real-time air pressure value and the real-time temperature value to obtain the real oxygen concentration.

Technical Field

The invention relates to the field of sensors, in particular to a dispersion type oxygen sensor and a control method thereof.

Background

At present, oxygen utilization equipment is provided with an oxygen concentration detection system, such as a breathing machine, an anesthesia machine, a central oxygen generator and the like, and an oxygen sensor is arranged in the oxygen utilization equipment for detecting the oxygen concentration.

Current oxygen check out test set is to the detection of oxygen concentration, and the structure is sealed relatively, can only detect through ventilating in the pipeline, and the formula space oxygen content that can not measure disperses, also is the oxygen concentration of open environment, and the adaptability is low.

Disclosure of Invention

The invention provides a dispersion type oxygen sensor and a control method thereof, aiming at solving the technical problems that the prior oxygen detection equipment has relatively closed structure and cannot measure the oxygen content in a dispersive space.

The first embodiment of the invention provides a dispersion type oxygen sensor, which comprises a shell, two ultrasonic probes and a control module, wherein the two ultrasonic probes are electrically connected with the control module; the shell comprises two channels, namely a first channel and a second channel, the first channel and the second channel are vertically designed, the inner diameter of the second channel is larger than that of the first channel, and the two ultrasonic probes are respectively plugged on two ports of the first channel; the first channel is communicated with the second channel at a position where the first channel and the second channel vertically intersect; the second channel is an open channel.

Preferably, the second channel is an air channel, and the first channel is an ultrasonic channel.

Preferably, the control module comprises a main control circuit, an air pressure detection module and a temperature detection module; the air pressure detection module and the temperature detection module are electrically connected with the microprocessor circuit; the master control circuit comprises a microprocessor circuit, a switching circuit, a filter circuit, an operational amplifier circuit and a comparison circuit; the comparison circuit is electrically connected with the microprocessor circuit, and the switching circuit, the filter circuit, the operational amplifier circuit and the comparison circuit are sequentially connected.

Preferably, the microprocessor module comprises a microprocessor U1, and the model number of the microprocessor U1 is STM32F103C8T 6.

Preferably, the switching circuit comprises a chip U5, a chip U6, a chip U8, a resistor R12; the A1 port of the chip U5 is connected with a power supply V4, the VCC port of the chip U5 is connected with a power supply V1, the GND port and the A2 port of the chip U5 are grounded, and the ENB port of the chip U5 is connected with the PWM port of the microprocessor circuit; the B port of the chip U5 is connected with the B port of the chip U6, and a resistor R12 is connected in series between the two ports; the VCC port of the chip U6 is connected with a power supply V2, the A1 port of the chip U6 is connected with the A2 port of the chip U8, the A2 port of the chip U6 is connected with the A1 port of the chip U8, the ENB port of the chip U6 is connected with the ENB port of the chip U8 and is connected with the ENB port of the microprocessor circuit, the VCC port of the chip U8 is connected with the power supply V3, and the GND port of the chip U6 and the GND port of the chip U8 are grounded; the models of the chip U5, the chip U6 and the chip U8 are the same as BL 1551.

Preferably, the filter circuit includes a diode D7, a diode D8, a capacitor C12, a resistor R23, and a resistor R24, the cathode of the diode D7 and the anode of the diode D8 are electrically connected to the resistor R24, one end of the resistor R23 is electrically connected to one end of the capacitor C12, and the anode of the diode D7 and the cathode of the diode D8 are grounded.

Preferably, the operational amplifier circuit comprises a chip U9, a resistor R13, a resistor R14, a resistor R29, a resistor R25, a resistor R26, a resistor R27, a resistor R28, a capacitor C11, a capacitor C13 and a capacitor C14; the V-port of the chip U9 is grounded, the a + port of the chip U9 is connected to the filter circuit and the comparator circuit, two ends of the resistor R25 are respectively connected to the a-port of the chip U9 and the port of the chip a0, the port of the chip a0 is connected to one end of the resistor R13 and one end of the capacitor C11, the other end of the resistor R13 is grounded, the other end of the capacitor C11 is electrically connected to one end of the resistor R14, the V + port of the chip U9 is connected to the power supply V6, the B0 port of the chip U9 is connected to one end of the resistor R29 and the comparator circuit, the B-port of the chip U9 is respectively connected to one end of the resistor R26 and one end of the resistor R28, the B + port of the chip U9 is respectively connected to one end of the capacitor C13 and one end of the resistor R27, the other end of the capacitor C11 is connected to one end of the resistor R14, and the other end of the resistor R14 is respectively connected to one end of the capacitor C13 and one end of the resistor R29, One end of a capacitor C14, and the other end of the capacitor C14 is respectively connected with one end of a resistor R26 and one end of a resistor R27; the chip U9 is model LMV 358.

Preferably, the comparison circuit comprises a chip U7, a resistor R16, a resistor R17, a resistor R15, a resistor R30, a resistor R32, a resistor R33, a resistor R34, a resistor R31 and a capacitor C15; the OUT port of the chip U7 is connected with a CH _ Up port of a micro-processing circuit and one end of a resistor R16, the 1 IN-port of the chip U7 is respectively connected with one end of a resistor R15 and the 2IN + port of the chip U7, the 2 IN-port of the chip U7 is connected with a resistor R33 and a resistor R34, and the 2OUT port of the chip U7 is connected with one end of a resistor R17 and the CH _ Down port of the micro-processing circuit; the resistor R30, the resistor R32, the resistor R33 and the resistor R34 are sequentially connected, the other end of the resistor R30 is connected with a power supply V10, one end of the resistor R31 is connected with the resistor R32, the resistor R33 and the capacitor C15, the other end of the capacitor C15 is grounded, and the other end of the resistor R34 is grounded; the chip U7 is model LMV 393.

Preferably, the air pressure detection module comprises a chip U4, a capacitor C7, a resistor R8 and a resistor R9; the chip U4 is characterized in that two ends of a VCC port and a GND port of the chip U4 are respectively connected with two ends of a capacitor C7, the VCC port of the chip U4 is connected with a power supply V1, the GND port of the chip U4 is grounded, the SDA port of the chip U4 is connected with one end of a resistor R8, the other end of the resistor R8 is connected with the power supply V1, the SCL port of the chip U4 is connected with one end of the resistor R9, the other end of the resistor R9 is connected with the power supply V1, the SDA port of the chip U4 is connected with the PA12 port of the chip U1, and the SCL port of the chip U4 is connected with the PA11 port of the chip U1; the chip U12 model is MS 5637.

A second embodiment of the present invention provides a method for controlling a dispersion type oxygen sensor, including the steps of:

step S1: the first channel and the second channel are filled with gas to be detected;

step S2: the microprocessor selects and excites the ultrasonic probe at one end to send out an ultrasonic signal, and the ultrasonic probe at the other end receives the ultrasonic signal to obtain the transmission time of the ultrasonic signal;

step S3: repeating the transmission of the ultrasonic signal in the gas for multiple times to obtain the real-time ultrasonic signal transmission time, and further converting the real-time oxygen concentration;

step S4: measuring a real-time air pressure value and a real-time temperature value through an air pressure detection module and a temperature detection module;

step S5: and (4) compensating and calculating the real-time oxygen concentration according to the real-time air pressure value and the real-time temperature value to obtain the real oxygen concentration.

Compared with the prior art, the diffusion type oxygen sensor and the control method thereof provided by the invention have the following advantages:

1. the second channel of the dispersion type oxygen sensor is filled with external gas, namely the gas is dispersed in the second channel, two ultrasonic probes are arranged at two ends of the first channel, ultrasonic waves are transmitted in the first channel and pass through the gas, the gas can influence the transmission rate of the ultrasonic waves, so that the transmission time of the ultrasonic waves under the equidistant condition is different along with the concentration of oxygen in the gas, the concentration of oxygen in the gas in the environment is converted through the transmission time of the ultrasonic waves, the common electrochemical sensor can be avoided, the problems of short service life and high cost of the common electrochemical sensor are solved, the use cost is reduced, further, the dispersion type oxygen sensor can measure the oxygen concentration of an open type oxygen environment, can be used in scenes such as medical treatment, oxygen bins and the like, and can also be used in daily living environments such as rooms, living environments and the like, The dispersion type oxygen sensor is suitable for open environment, and the measured oxygen concentration range of the oxygen environment is improved from 21-95% to 0-100%.

2. The air pressure detection module and the temperature detection module can acquire real-time air pressure and temperature, and meanwhile, the dispersion type oxygen sensor is used for measuring oxygen in an open mode, so that the dispersion type oxygen sensor can be used in medical treatment, oxygen bins and other scenes, and a user can have accurate data in such scenes to perform daily operation and activities.

3. The air pressure detection module, the temperature detection module, the microprocessor circuit, the switching circuit, the filter circuit, the operational amplifier circuit and the comparison circuit are integrated on the same circuit board, so that the working reliability of the circuit of the whole machine is improved, the working performance and consistency of the circuit are improved, and the energy consumption of the oxygen sensor is reduced; furthermore, the additional special measuring elements can be reduced, the occupied space can be saved, the space occupancy rate of the dispersion type oxygen sensor is saved, and the cost of the device is reduced.

4. Through the cooperation of the switching circuit, the filter circuit, the operational amplifier circuit and the operational amplifier circuit, the ultrasonic wave propagation time under the condition that the first channel and the second channel have gas propagation is obtained, and the real-time speed of the ultrasonic wave is calculated, so that the concentration and the flow of the current oxygen are obtained, the error rate of measurement is reduced, and the accuracy of the measurement result of the dispersion type and pipeline combined type oxygen detection device is improved.

5. The first channel and the second channel are in an open environment, gas to be detected is filled in the first channel and the second channel, the microprocessor selects and excites the ultrasonic probe at one end to send out an ultrasonic signal, the other end receives the ultrasonic signal, the ultrasonic signal is transmitted in the second channel and passes through the gas in the first channel to obtain the transmission time T1 of the ultrasonic signal, the ultrasonic probe repeats the steps at a certain frequency to obtain the real-time transmission time of the ultrasonic, and the real-time oxygen concentration C1 is converted; the real-time air pressure value P and the real-time temperature value Te are measured through the air pressure detection module and the temperature detection module, corresponding calculation coefficients are obtained by utilizing the obtained real-time oxygen concentration C1, the real-time air pressure value P and the real-time temperature value Te to compensate the real-time oxygen concentration, the concentration is converted through a conversion formula to obtain the real oxygen concentration, and the real oxygen concentration is obtained through the compensation conversion of the air pressure and the temperature of the real-time oxygen concentration to achieve the measurement accuracy, so that the measurement accuracy is improved, the device is suitable for being used in the plateau area environment, the actual oxygen concentration is reduced due to the low air pressure of the plateau area and is reacted to be calculated through the compensation reaction, further, the first channel and the second channel are designed in an open mode, gas is filled in the first channel and the second channel, the measurement range is increased, and the measured oxygen concentration reaches 0-100%, the environment for adapting the measurement of the dispersion type oxygen sensor is more diversified.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit of the present invention are intended to be included within the scope of the present invention.

Drawings

FIG. 1 is a first schematic diagram illustrating an overall structure of a diffusion-type oxygen sensor according to a first embodiment of the present invention;

FIG. 2 is a schematic diagram of the overall structure of a dispersion-type oxygen sensor according to a first embodiment of the present invention;

FIG. 3 is a block diagram of a control module of a diffusion-type oxygen sensor according to a first embodiment of the present invention;

FIG. 4 is a circuit diagram of a gas pressure detecting module of a diffusion-type oxygen sensor according to a first embodiment of the present invention;

FIG. 5 is a circuit diagram of a temperature detection module of a dispersion type oxygen sensor according to a first embodiment of the present invention;

FIG. 6 is a switching circuit diagram of a diffusion-type oxygen sensor according to a first embodiment of the present invention;

FIG. 7 is a diagram of a filter circuit and an operational amplifier circuit of a dispersion-type oxygen sensor according to a first embodiment of the present invention;

FIG. 8 is a comparative circuit diagram of a diffusion-type oxygen sensor according to a first embodiment of the present invention;

fig. 9 is a specific flowchart of a diffusion type oxygen sensor control method according to a second embodiment of the present invention.

Description of reference numerals:

100. a dispersion type oxygen sensor;

1. a housing; 2. an ultrasonic probe; 3. a control module;

11. a first channel; 12. a second channel;

31 a master control circuit; 32. an air pressure detection module; 33. a temperature detection module;

311. a microprocessor circuit; 312. a switching circuit; 313. a filter circuit; 314. an operational amplifier circuit; 315. a comparison circuit.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 1-3, a first embodiment of the invention provides a dispersion type oxygen sensor 100 for testing oxygen concentration in an open environment, such as indoor and outdoor measurement, comprising a housing 1, two ultrasonic probes 2 and a control module 3, wherein the two ultrasonic probes 2 are electrically connected to the control module 3.

Specifically, the ultrasonic waves in the housing 1 propagate in the gas, the ultrasonic probes 2 are used for transmitting or receiving the ultrasonic waves, the control module 3 is used for controlling the ultrasonic probes 2 to transmit the ultrasonic waves and measure the propagation time of the ultrasonic waves, the control module 3 controls the two ultrasonic probes 2, one ultrasonic probe 2 transmits the ultrasonic waves, the other ultrasonic probe 2 receives the ultrasonic waves, the propagation rate of the ultrasonic waves is calculated through the distance between the probes and the propagation time of the ultrasonic waves between the two ultrasonic probes 2, and then the concentration of the oxygen in the current gas is calculated.

The shell 1 comprises two channels, including a first channel 11 and a second channel 12, the first channel 11 and the second channel 12 are designed vertically, the inner diameter of the second channel 12 is larger than that of the first channel 11, and the two ultrasonic probes 2 are respectively blocked on two ports of the first channel 11.

Specifically, the second channel 12 is an air channel, the first channel 11 is an ultrasonic channel, and the first channel 11 is communicated with the second channel 12 at a position where the two channels intersect vertically; the second channel 12 is an open channel.

It can be understood that the second channel 12 is filled with external gas, that is, the gas is dispersed in the second channel 12, two ultrasonic probes 2 are arranged at two ends of the first channel 11, the ultrasonic wave is transmitted in the first channel 11, and the gas can affect the transmission rate of the ultrasonic wave, so that the transmission time of the ultrasonic wave is different along with the concentration of oxygen in the gas under the condition of equidistance, and the concentration of oxygen in the environment is converted by the transmission time of the ultrasonic wave, thereby avoiding using a common electrochemical sensor, getting rid of the problems of short service life and high cost of the common electrochemical sensor, reducing the use cost, further, the dispersion type oxygen sensor 100 can measure the oxygen concentration in an open oxygen environment, can be used in the scenes of medical treatment, oxygen bins and the like, and can also be used in the daily living environment, for example, in indoor environments such as rooms and offices, the dispersion-type oxygen sensor 100 has strong applicability, and further, the dispersion-type oxygen sensor is suitable for open environments, the oxygen concentration range of the measured oxygen environment is improved and can be increased from 21-95% to 0-100%, the oxygen concentration can be detected in the high-altitude air scarcity, and the applicability of the dispersion-type oxygen sensor 100 is improved.

The control module 3 comprises a main control circuit 31, an air pressure detection module 32 and a temperature detection module 33; the air pressure detection module 32 and the temperature detection module 33 are electrically connected to the microprocessor circuit 311; the air pressure detection module 32 is used for detecting the air pressure of the oxygen environment, and the temperature detection module 33 is used for detecting the temperature of the oxygen environment.

The air pressure detection module 32 and the temperature detection module 33 can acquire real-time air pressure and temperature, and meanwhile, the dispersion type oxygen sensor 100 is used for measuring oxygen in an open mode, so that the dispersion type oxygen sensor 100 can be used in medical treatment, oxygen bins and other scenes, and a user can have accurate data in such scenes to perform daily operation and activities.

Referring to fig. 4, the air pressure detecting module 32 includes a chip U4, a capacitor C7, a resistor R8, and a resistor R9;

the chip U4 is characterized in that two ends of a VCC port and a GND port of the chip U4 are respectively connected with two ends of a capacitor C7, the VCC port of the chip U4 is connected with a power supply V1, the GND port of the chip U4 is grounded, the SDA port of the chip U4 is connected with one end of a resistor R8, the other end of the resistor R8 is connected with the power supply V1, the SCL port of the chip U4 is connected with one end of the resistor R9, the other end of the resistor R9 is connected with the power supply V1, the SDA port of the chip U4 is connected with the PA12 port of the chip U1, and the SCL port of the chip U4 is connected with the PA11 port of the chip U1;

the chip U12 model is MS 5637.

Specifically, the chip U4 is a pressure sensor, and is used for detecting current atmospheric pressure, monitoring atmospheric pressure in real time, calculating the altitude of the current user through atmospheric pressure, and since atmospheric pressure changes with the altitude, the density of gas changes, and the speed of ultrasound also changes, and according to the current atmospheric pressure, the calculated oxygen concentration is compensated in real time to obtain an accurate concentration value, and the accuracy and the real-time performance of measurement are improved.

Referring to fig. 5, the temperature detecting module 33 includes a temperature sensor, the temperature detecting module 33 is electrically connected to the microprocessor circuit 311, and the temperature sensor is used for sensing a current temperature and compensating for a real-time oxygen concentration by acquiring a real-time temperature, so that measured data is more accurate.

Referring to fig. 3, the main control circuit 31 includes a microprocessor circuit 311, a switching circuit 312, a filter circuit 313, an operational amplifier circuit 314, and a comparator circuit 315; the comparison circuit 315 is electrically connected to the microprocessor circuit 311, and the switching circuit 312, the filter circuit 313, the operational amplifier circuit 314, and the comparison circuit 315 are sequentially connected.

Specifically, the microprocessor circuit 311 is used for controlling each module circuit of the control module 3, and the microprocessor module comprises a microprocessor U1, wherein the model of the microprocessor U1 is STM32F103C8T6 through an electric signal control and regulation circuit.

Furthermore, the air pressure detection module 32, the temperature detection module 33, the microprocessor circuit 311, the switching circuit 312, the filter circuit 313, the operational amplifier circuit 314 and the comparison circuit 315 are integrated on the same circuit board, so that the working reliability of the circuit of the whole machine is improved, the working performance and consistency of the circuit are improved, and the energy consumption of the oxygen sensor is reduced; further, the additional arrangement of special measuring elements can be reduced, the occupied space can be saved, the space occupancy rate of the dispersion type oxygen sensor 100 can be saved, and the cost of the device can be reduced.

Referring to fig. 6-8, the switching circuit 312 includes a chip U5, a chip U6, a chip U8, and a resistor R12;

the A1 port of the chip U5 is connected with a power supply V4, the VCC port of the chip U5 is connected with a power supply V1, the GND port and the A2 port of the chip U5 are grounded, and the ENB port of the chip U5 is connected with the PWM port of the microprocessor circuit 311; the B port of the chip U5 is connected with the B port of the chip U6, and a resistor R12 is connected in series between the two ports; the VCC port of the chip U6 is connected with a power supply V2, the A1 port of the chip U6 is connected with the A2 port of the chip U8, the A2 port of the chip U6 is connected with the A1 port of the chip U8, the ENB port of the chip U6 is connected with the ENB port of the chip U8 and is connected with the ENB port of the microprocessor circuit 311, the VCC port of the chip U8 is connected with the power supply V3, the GND port of the chip U6 and the GND port of the chip U8 are grounded; the models of the chip U5, the chip U6 and the chip U8 are the same as BL 1551.

The filter circuit 313 includes a diode D7, a diode D8, a capacitor C12, a resistor R23, and a resistor R24, wherein a cathode of the diode D7 and an anode of the diode D8 are electrically connected to the resistor R24, one end of the resistor R23 is electrically connected to one end of the capacitor C12, and an anode of the diode D7 and a cathode of the diode D8 are grounded.

The operational amplifier circuit 314 comprises a chip U9, a resistor R13, a resistor R14, a resistor R29, a resistor R25, a resistor R26, a resistor R27, a resistor R28, a capacitor C11, a capacitor C13 and a capacitor C14; the V-port of the chip U9 is grounded, the A + port of the chip U9 is connected with the filter circuit 313 and the comparison circuit 315, two ends of the resistor R25 are respectively connected with the A-port of the chip U9 and the A0 port, the A0 port of the chip is connected with one end of the resistor R13 and one end of the capacitor C11, the other end of the resistor R13 is grounded, the other end of the capacitor C11 is electrically connected with one end of the resistor R14, the V + port of the chip U9 is connected with the power supply V6, the B0 port of the chip U9 is connected with one end of the resistor R29 and the comparison circuit 315, the B-port of the chip U9 is respectively connected with one end of the resistor R26 and one end of the resistor R28, the B + port of the chip U9 is respectively connected with one end of the capacitor C13 and one end of the resistor R27, the other end of the capacitor C11 is connected with one end of the resistor R14, and one end of the resistor R14 is respectively connected with one end of the capacitor C13, One end of a resistor R29 and one end of a capacitor C14, and the other end of the capacitor C14 is respectively connected with one end of a resistor R26 and one end of a resistor R27; the chip U9 is model LMV 358.

The comparison circuit 315 includes a chip U7, a resistor R16, a resistor R17, a resistor R15, a resistor R30, a resistor R32, a resistor R33, a resistor R34, a resistor R31, and a capacitor C15; the OUT port of the chip U7 is connected with a CH _ Up port of a micro-processing circuit and one end of a resistor R16, the 1 IN-port of the chip U7 is respectively connected with one end of a resistor R15 and the 2IN + port of the chip U7, the 2 IN-port of the chip U7 is connected with a resistor R33 and a resistor R34, and the 2OUT port of the chip U7 is connected with one end of a resistor R17 and the CH _ Down port of the micro-processing circuit 311; the resistor R30, the resistor R32, the resistor R33 and the resistor R34 are sequentially connected, the other end of the resistor R30 is connected with a power supply V10, one end of the resistor R31 is connected with the resistor R32, the resistor R33 and the capacitor C15, the other end of the capacitor C15 is grounded, and the other end of the resistor R34 is grounded; the chip U7 is model LMV 393.

Specifically, the two ultrasonic probes 2 transmit and receive the ultrasonic signals, the two ultrasonic probes 2 can be used as a receiving end or a transmitting end respectively, the ultrasonic propagation path is a plurality of paths, and the switching circuit 312 switches the signal transmission direction by controlling the channel, so as to ensure that the ultrasonic signal propagation path is the distance between the two ultrasonic probes 2, ensure that the ultrasonic transmission heights are consistent and the paths are consistent in any ultrasonic transmission direction, and reduce the transmission error.

Specifically, the RC filter circuit 313 is formed by a capacitor and a resistor, and the filter circuit 313 is used for filtering interference noise introduced by the input end and eliminating adverse effects caused by jitter generated when the external input point operates.

It can be understood that because ultrasonic signal can receive influence such as external voltage, residual wave, ultrasonic probe 2 receives behind the ultrasonic signal of gaseous transmission, through filtering and amplification, makes signal noise removal and filtering clutter to with signal amplification, so that subsequent processing avoids other factors to influence measuring result, improves measuring accuracy.

Specifically, the operational amplifier circuit 314 acquires and captures an effective signal after operational amplification, compares the filtered and amplified signal, and obtains a current signal transmission direction, and the microprocessor circuit 311 obtains the current signal transmission direction so as to define a transmission time direction of the signal, thereby facilitating subsequent calculation and improving the accuracy of the diffusion oxygen sensor 100.

It can be understood that the switching circuit 312, the filter circuit 313, the operational amplifier circuit 314 and the operational amplifier circuit 314 are matched to obtain the propagation time of the ultrasonic waves under the condition that the gas propagates through the first channel 11 and the second channel 12, and calculate the real-time rate of the ultrasonic waves, so as to obtain the concentration and the flow rate of the current oxygen, reduce the error rate of the measurement and improve the accuracy of the measurement result of the diffusion type oxygen sensor 100.

The working principle is as follows:

the two ultrasonic probes 2 at the two ends of the first channel 11 and the second channel 12 are respectively connected in a circuit, the microprocessor circuit 311 selectively excites one of the ultrasonic probes 2 to send out an ultrasonic signal, and the other ultrasonic probe 2 receives the sent signal. In the process, the microprocessor circuit 311 sends out pulse waves with fixed frequency to excite the ultrasonic probe A at one end to send out a transmitting wave signal, the receiving channel of the ultrasonic probe B at the other end is opened through the switch circuit, the signal sent out by the ultrasonic probe A reaches the ultrasonic probe B through the open cavity, and the ultrasonic probe B receives a receiving signal; filtering and amplifying the received signal received by the ultrasonic probe 2B to obtain a better usable signal, and then capturing the channel signal by the microprocessor circuit 311 through the capture comparator via the comparison circuit 315 to obtain a time value from the time when the ultrasonic probe a sends the signal to the time when the ultrasonic probe B receives the signal; the microprocessor circuit 311 repeats the above process at a certain frequency to obtain the real-time transmission time of the ultrasound, so as to convert the oxygen concentration, meanwhile, the air pressure detection module 32 and the temperature detection module 33 also monitor the air pressure and temperature data in real time, and the microprocessor circuit 311 compensates the calculated oxygen concentration in real time according to the measured air pressure and temperature data, so as to obtain a more accurate concentration value.

Referring to fig. 9, a second embodiment of the present invention provides a method for controlling a dispersion-type oxygen sensor, which is applied to the dispersion-type oxygen sensor in the first embodiment, and specifically includes the following steps:

step S1: the first channel and the second channel are filled with gas to be detected;

step S2: the microprocessor selects and excites the ultrasonic probe at one end to send out an ultrasonic signal, and the ultrasonic probe at the other end receives the ultrasonic signal to obtain the transmission time of the ultrasonic signal;

step S3: repeating the transmission of the ultrasonic signal in the gas for multiple times to obtain the real-time ultrasonic signal transmission time, and further converting the real-time oxygen concentration;

step S4: measuring a real-time air pressure value and a real-time temperature value through an air pressure detection module and a temperature detection module;

step S5: and (4) compensating and calculating the real-time oxygen concentration according to the real-time air pressure value and the real-time temperature value to obtain the real oxygen concentration.

It can be understood that, the first channel and the second channel are in an open environment, the first channel and the second channel are filled with gas to be measured, the microprocessor selects and excites the ultrasonic probe at one end to send out an ultrasonic signal, the other end receives the ultrasonic signal, the ultrasonic signal is transmitted in the second channel and passes through the gas in the first channel to obtain the ultrasonic signal transmission time T1, the ultrasonic probe repeats the steps at a certain frequency to obtain the real-time transmission time of the ultrasonic, and thus the real-time oxygen concentration C1 is calculated; measure real-time atmospheric pressure value P and real-time temperature value Te through atmospheric pressure detection module, temperature detection module, utilize real-time oxygen concentration C1, real-time atmospheric pressure value P and real-time temperature value Te that obtain to obtain corresponding calculation coefficient to compensate real-time oxygen concentration, convert concentration through the conversion formula, obtain real oxygen concentration, the conversion formula is:

C＝((T1+(Te-30)*Kt)*K1)*P/Kp+20.8

wherein C is the concentration of oxygen, and Kt is the compensation coefficient of temperature; k1 is the calculated coefficient for different oxygen concentrations and Kp is the pressure compensation coefficient.

The temperature compensation coefficient Kt obtains approximate change of a time value of each temperature change under different temperature environments to serve as the temperature compensation coefficient Kt; the calculation coefficients K1 in different oxygen concentrations are compared through known concentrations to calculate the calculation coefficient K1 in different oxygen concentrations; the pressure compensation coefficient Kp is the pressure and concentration relation and the pressure compensation coefficient Kp measured in different pressure environments under the same concentration condition.

The real oxygen concentration is obtained through compensation conversion of air pressure and temperature on the real-time oxygen concentration, so that the measuring accuracy is achieved, the device is suitable for being used in the plateau area environment, the actual oxygen concentration is reduced due to low air pressure in the plateau area and is calculated through compensation reaction, the measuring accuracy is improved, furthermore, the first channel and the second channel are designed in an open mode, gas is diffused in the first channel and the second channel, the measuring range is increased, the measured oxygen concentration is enabled to reach 0-100%, and the environment of adaptation measured by the dispersion type oxygen sensor is enabled to be more diverse.

Compared with the prior art, the diffusion type oxygen sensor and the control method thereof provided by the invention have the following advantages:

1. the second channel of the dispersion-type oxygen sensor is filled with external gas, namely the gas is dispersed in the second channel, two ultrasonic probes are arranged at two ends of the first channel, ultrasonic waves are transmitted in the first channel and pass through the gas, the gas can influence the transmission rate of the ultrasonic waves, so that the transmission time of the ultrasonic waves under the equidistant condition is different along with the concentration of oxygen in the gas, the concentration of oxygen in the gas in the environment is converted through the transmission time of the ultrasonic waves, the common electrochemical sensor can be avoided, the problems of short service life and high cost of the common electrochemical sensor are solved, the use cost is reduced, further, the dispersion-type oxygen sensor 100 can measure the oxygen concentration in an open oxygen environment, can be used in scenes such as medical treatment, oxygen bins and the like, and can also be used in daily living environments such as rooms, living environments and the like, The dispersion-type oxygen sensor 100 is suitable for an open environment, and the measured oxygen concentration range of the oxygen environment is improved from 21-95% to 0-100%.

2. The air pressure detection module and the temperature detection module can acquire real-time air pressure and temperature, and meanwhile, the dispersion type oxygen sensor is used for measuring oxygen in an open mode, so that the dispersion type oxygen sensor can be used in medical treatment, oxygen bins and other scenes, and a user can have accurate data in such scenes to perform daily operation and activities.

3. The air pressure detection module, the temperature detection module, the microprocessor circuit, the switching circuit, the filter circuit, the operational amplifier circuit and the comparison circuit are integrated on the same circuit board, so that the working reliability of the circuit of the whole machine is improved, the working performance and consistency of the circuit are improved, and the energy consumption of the oxygen sensor is reduced; furthermore, the additional special measuring elements can be reduced, the occupied space can be saved, the space occupancy rate of the dispersion type oxygen sensor is saved, and the cost of the device is reduced.

4. Through the cooperation of the switching circuit, the filter circuit, the operational amplifier circuit and the operational amplifier circuit, the ultrasonic wave propagation time under the condition that the first channel and the second channel have gas propagation is obtained, and the real-time speed of the ultrasonic wave is calculated, so that the concentration and the flow of the current oxygen are obtained, the error rate of measurement is reduced, and the accuracy of the measurement result of the dispersion type and pipeline combined type oxygen detection device is improved.

5. The first channel and the second channel are in an open environment, gas to be detected is filled in the first channel and the second channel, the microprocessor selects and excites the ultrasonic probe at one end to send out an ultrasonic signal, the other end receives the ultrasonic signal, the ultrasonic signal is transmitted in the second channel and passes through the gas in the first channel to obtain the transmission time T1 of the ultrasonic signal, the ultrasonic probe repeats the steps at a certain frequency to obtain the real-time transmission time of the ultrasonic, and the real-time oxygen concentration C1 is converted; the real-time air pressure value P and the real-time temperature value Te are measured through the air pressure detection module and the temperature detection module, corresponding calculation coefficients are obtained by utilizing the obtained real-time oxygen concentration C1, the real-time air pressure value P and the real-time temperature value Te to compensate the real-time oxygen concentration, the concentration is converted through a conversion formula to obtain the real oxygen concentration, and the real oxygen concentration is obtained through the compensation conversion of the air pressure and the temperature of the real-time oxygen concentration to achieve the measurement accuracy, so that the measurement accuracy is improved, the device is suitable for being used in the plateau area environment, the actual oxygen concentration is reduced due to the low air pressure of the plateau area and is reacted to be calculated through the compensation reaction, further, the first channel and the second channel are designed in an open mode, gas is filled in the first channel and the second channel, the measurement range is increased, and the measured oxygen concentration reaches 0-100%, the environment for adapting the measurement of the dispersion type oxygen sensor is more diversified.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit of the present invention are intended to be included within the scope of the present invention.