Ultrasonic oxygen sensor

Abstract

The utility model discloses an ultrasonic oxygen sensor. The ultrasonic oxygen sensor comprises a circuit board and an ultrasonic pipe fitting arranged above the circuit board, a controller is arranged on the circuit board and connected with the temperature and humidity sensor, the pressure sensor, the first binding post and the second binding post. The ultrasonic pipe fitting comprises a gas pipeline, a first ultrasonic probe and a second ultrasonic probe are arranged at the two ends of the gas pipeline respectively, the first ultrasonic probe is connected with the first binding post, and the second ultrasonic probe is connected with the second binding post; a gas inlet joint and a gas outlet joint are respectively arranged on one side of the gas pipeline; a first opening and a second opening are formed in the bottom of the gas pipeline, the first opening corresponds to the temperature and humidity sensor, and the second opening corresponds to the pressure sensor. According to the ultrasonic oxygen sensor, the problem that the temperature and humidity sensor and the pressure sensor interfere with each other is effectively avoided, and the measurement precision and stability of the ultrasonic oxygen sensor are effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of oxygen detection, in particular to an ultrasonic oxygen sensor. Background Art

[0002] Chinese Patent (Publication No. CN217981351U) proposes an ultrasonic oxygen concentration and mass measurement device, which can make up for the deficiencies of traditional oxygen sensors (such as gas chromatography and optical method sensors), has a simple structure, is easy to use, and has high stability. While ensuring the measurement accuracy, it also reduces the production cost. The ultrasonic oxygen concentration and mass measurement device includes an MCU chip, a first ultrasonic oscillator, a second ultrasonic oscillator, a pressure sensor, a temperature sensor, a control board and a cavity. The pressure sensor and the temperature sensor are both accommodated in the cavity. The cavity is fixed on the control board. The two ultrasonic oscillators are respectively fixed in the cavity, and their power supply pins are installed on the control board. The emitting surfaces of the first ultrasonic oscillator and the second ultrasonic oscillator are parallel and opposite to each other. The MCU chip is electrically connected to the first ultrasonic oscillator, the second ultrasonic oscillator, the pressure sensor and the temperature sensor respectively. One end of the cavity is provided with an air inlet, and the other end is provided with an air outlet.

[0003] Its disadvantages are that a humidity sensor is not provided in the ultrasonic oxygen concentration and mass measurement device, so the influence of humidity on the oxygen concentration cannot be detected. And the pressure sensor and the temperature sensor are both installed in a circular hole groove, resulting in the installation positions of the two being too close, there is mutual interference, and thus the measurement accuracy of the overall device decreases. Summary of the Utility Model

[0004] The main purpose of the utility model is to propose an acoustic wave oxygen sensor, aiming to solve the technical problems in the prior art that the influence of humidity on the oxygen concentration cannot be detected, and the installation positions of the pressure sensor and the temperature sensor are too close, resulting in a decrease in measurement accuracy.

[0005] To achieve the above purpose, the utility model provides an ultrasonic oxygen sensor, including: a circuit board and an ultrasonic pipe fitting installed above the circuit board;

[0006] A controller, a temperature and humidity sensor, a pressure sensor, a first terminal and a second terminal are arranged on the circuit board. The controller is respectively connected to the temperature and humidity sensor, the pressure sensor, the first terminal and the second terminal;

[0007] The ultrasonic pipe fitting includes a gas pipeline, a first ultrasonic probe, a second ultrasonic probe, an air inlet joint and an air outlet joint. The first ultrasonic probe and the second ultrasonic probe are respectively arranged at both ends of the gas pipeline. The first ultrasonic probe is connected to the first terminal, and the second ultrasonic probe is connected to the second terminal. The air inlet joint and the air outlet joint are respectively arranged on one side of the gas pipeline. The bottom of the gas pipeline is provided with a first opening and a second opening. The first opening corresponds to the temperature and humidity sensor, and the second opening corresponds to the pressure sensor.

[0008] Preferably, the ultrasonic oxygen sensor further includes a first base and a second base. The ultrasonic pipe fitting is installed on the circuit board through the first base and the second base. The first base is provided with a first channel adapted to the first opening, and the second base is provided with a second channel adapted to the second opening. Both the first channel and the second channel are communicated with the inside of the gas pipeline.

[0009] Preferably, grooves adapted to the gas pipeline are provided in the middle of the first base and the second base.

[0010] Preferably, screw mounting holes are provided on both sides of the first base and the second base.

[0011] Preferably, a voltage converter, a first ultrasonic driver, a second ultrasonic driver and a power supply connector are further provided on the circuit board. The power supply connector is connected to the input end of the voltage converter. The output end of the voltage converter is respectively connected to the power supply ends of the controller, the temperature and humidity sensor, the pressure sensor, the first ultrasonic driver and the second ultrasonic driver. The controller is connected to the first terminal through the first ultrasonic driver, and the controller is connected to the second terminal through the second ultrasonic driver.

[0012] Preferably, the voltage converter includes a voltage stabilizing chip, a TVS tube, a second capacitor and a third capacitor. The input end of the voltage stabilizing chip is respectively grounded through the TVS tube and the third capacitor. The output end of the voltage stabilizing chip is grounded through the second capacitor, and the output end of the voltage stabilizing chip is used to output a first voltage source.

[0013] Preferably, the controller includes a main control chip and a first capacitor. The power supply end of the main control chip is grounded through the first capacitor.

[0014] Preferably, the temperature and humidity sensor includes a temperature and humidity sensor chip and a fifth capacitor. The temperature and humidity sensor chip is communicatively connected to the main control chip through an I2C interface. The power supply end of the temperature and humidity sensor chip is grounded through the fifth capacitor.

[0015] Preferably, the pressure sensor includes a pressure sensor chip, a first resistor, a second resistor, a third resistor, and a fourth capacitor; the power supply terminal of the pressure sensor chip is grounded through the fourth capacitor, the clock line pin of the pressure sensor chip is connected to the first voltage source through the second resistor, the data line pin of the pressure sensor chip is connected to the first voltage source through the third resistor, and the serial data output pin of the pressure sensor chip is grounded through the first resistor; the pressure sensor chip is communicatively connected to the main control chip through the clock line pin and the data line pin.

[0016] Preferably, the first ultrasonic driver includes a first driving chip; the signal input terminal of the first driving chip is connected to the first signal output terminal of the main control chip, and the voltage output terminal of the first driving chip is connected to the first ultrasonic probe through the first terminal block;

[0017] The second ultrasonic driver includes a second driving chip; the signal input terminal of the second driving chip is connected to the second signal output terminal of the main control chip, and the voltage output terminal of the second driving chip is connected to the second ultrasonic probe through the second terminal block.

[0018] The above ultrasonic oxygen sensor has the following beneficial effects:

[0019] 1) The ultrasonic oxygen sensor of the present invention is internally provided with a temperature and humidity sensor and a pressure sensor, which can calibrate the oxygen concentration by using the temperature and humidity data and the pressure data, improving the accuracy of oxygen concentration measurement; at the same time, by integrating the temperature and humidity sensor and the pressure sensor, the volume of the ultrasonic oxygen sensor is effectively reduced, the integration degree is improved, and a stable measurement environment can be provided for oxygen concentration detection;

[0020] 2) In the ultrasonic oxygen sensor of the present invention, the ultrasonic pipe fitting is provided with a first opening and a second opening at a certain distance. The first opening corresponds to the temperature and humidity sensor on the circuit board, and the second opening corresponds to the pressure sensor on the circuit board. This setting can avoid the problem of mutual interference between the temperature and humidity sensor and the pressure sensor, effectively ensuring the measurement accuracy of the ultrasonic oxygen sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic structural diagram of the ultrasonic oxygen sensor in an embodiment of the present invention Figure One ;

[0022] Figure 2 is a schematic structural diagram of the ultrasonic oxygen sensor in an embodiment of the present invention Figure Two ;

[0023] Figure 3 Structural schematic of an ultrasonic oxygen sensor in an embodiment of the present utility model Figure Three ;

[0024] Figure 4 is Figure 3 a cross-sectional schematic diagram along line A-A in

[0025] Figure 5 Internal cross-sectional view of an ultrasonic oxygen sensor in an embodiment of the present utility model;

[0026] Figure 6 Circuit diagram of the circuit board of an ultrasonic oxygen sensor in an embodiment of the present utility model.

[0027] The serial numbers in the figure are as follows:

[0028] 1. Circuit board; 2. Gas pipeline; 3a. First ultrasonic probe; 3b. Second ultrasonic probe; 4. Intake joint; 5. Exhaust joint; 6a. First base; 601. First channel; 602. Screw mounting hole; 6b. Second base; 7a. First terminal; 7b. Second terminal; 8. Controller; 9. Temperature and humidity sensor; 10. Pressure sensor; 11. Voltage converter; 12a. First ultrasonic driver; 12b. Second ultrasonic driver; 13. Power supply joint. Detailed implementation manners

[0029] To better understand the above technical solutions, the exemplary embodiments of the present utility model will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present utility model are shown in the drawings, it should be understood that the present utility model can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present utility model and to fully convey the scope of the present utility model to those skilled in the art.

[0030] It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.

[0031] It should be noted that in the embodiments of the present utility model, the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model.

[0032] In the present utility model, unless otherwise clearly defined and limited, the terms "installed", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0033] In the present utility model, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over", and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "below", "beneath", and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0034] Refer to Figures 1 to 6 , the embodiments of the present utility model provide an ultrasonic oxygen sensor, which is mainly used for detecting the oxygen concentration, flow rate, pressure, temperature and humidity of a ventilator. The ultrasonic oxygen sensor includes: a circuit board 1 and an ultrasonic pipe fitting installed above the circuit board 1.

[0035] Among them, a controller 8, a temperature and humidity sensor 9, a pressure sensor 10, a first terminal 7a and a second terminal 7b are arranged on the circuit board 1; the controller 8 is respectively connected to the temperature and humidity sensor 9, the pressure sensor, the first terminal 7a and the second terminal 7b.

[0036] The ultrasonic pipe fitting includes a gas pipeline 2, a first ultrasonic probe 3a, a second ultrasonic probe 3b, an air inlet joint 4, and an air outlet joint 5. The first ultrasonic probe 3a and the second ultrasonic probe 3b are respectively arranged at both ends of the gas pipeline 2. The first ultrasonic probe 3a is connected to the first terminal 7a, and the second ultrasonic probe 3b is connected to the second terminal 7b. The air inlet joint 4 and the air outlet joint 5 are respectively arranged on one side of the gas pipeline 2. The bottom of the gas pipeline 2 is provided with a first opening and a second opening, and the first opening and the second opening are symmetrically distributed along the center line of the length direction of the gas pipeline 2, and the center of the opening is about 20 millimeters away from the center line. The first opening corresponds to the temperature and humidity sensor 9, and the second opening corresponds to the pressure sensor 10.

[0037] In this embodiment, a controller 8 is arranged on the circuit board 1. The controller 8 is respectively connected to a temperature and humidity sensor 9, a pressure sensor 10, and two terminals, and the terminals are connected to the ultrasonic probes of the ultrasonic pipe fitting. At this time, the controller 8 can control the first ultrasonic probe 3a and the second ultrasonic probe 3b to alternately transmit and receive ultrasonic signals, measure the oxygen flow rate based on the Doppler effect, and then calculate the oxygen concentration based on the corresponding relationship between the oxygen concentration and the oxygen flow rate, and obtain the temperature and humidity data measured by the temperature and humidity sensor 9 in real time and the pressure data measured by the pressure sensor 10 in real time, and calibrate the calculated oxygen concentration using the temperature and humidity data and the pressure data. More specifically, the measurement process of the oxygen concentration can be as follows:

[0038] First, the controller 9 measures the time T required for the forward ultrasonic wave to pass through the gas pipeline 2 ab , and the time T required for the reverse ultrasonic wave to pass through the gas pipeline 2 ab . Combining the distance L between the first ultrasonic probe 3a and the second ultrasonic probe 3b, calculate the ultrasonic wave speed C in the gas pipeline 2. The calculation formula for the ultrasonic wave speed C is:

[0039] Formula (1), C = 0.5 * (L / T ab + L / T ba ),

[0040] Correspondingly, the oxygen flow rate in the gas pipeline 2 is:

[0041] Formula (2), C1 = 0.5 * (L / T ab - L / T ba ),

[0042] Then, using the sound speed model of the ideal gas, reverse-derive the calculation formula for the gas constant Rg of the current gas, where the sound speed model of the ideal gas is:

[0043] Formula (3),

[0044] In Equation (3), C is the speed of sound in an ideal gas, k is the adiabatic coefficient of the gas, and T is the gas temperature T in the constant-length pipeline.

[0045] The calculation formula for the gas constant Rg of the current gas is:

[0046] Formula (4),

[0047] In Equation (4), Rg(O2) is the gas constant of pure oxygen, Rg(O2) = 259.8 J / (kg·K), Rg(Air) is the gas constant of air, Rg(Air) = 287 J / (kg·K), and x is the oxygen concentration.

[0048] Finally, using Formula (4), the oxygen concentration x is obtained as:

[0049] x = {294.23 - C 2 / (k * T)} / 34.43.

[0050] The ultrasonic pipe fitting includes a gas pipeline 2, and a first ultrasonic probe 3a and a second ultrasonic probe 3b are installed at both ends of the gas pipeline 2. An air inlet joint 4 and an air outlet joint 5 are respectively arranged on the same side of the gas pipeline 2, and the air inlet joint 4 is close to the first ultrasonic probe 3a, and the air outlet joint 5 is close to the second ultrasonic probe 3b. A first opening and a second opening are respectively arranged at a certain distance at the bottom of the gas pipeline 2, and the first opening corresponds to the temperature and humidity sensor 9 on the circuit board 1, and the second opening corresponds to the pressure sensor 10 on the circuit board 1. At this time, oxygen enters the gas pipeline 2 through the air inlet joint 4, passes through the temperature and humidity sensor 9 at the position corresponding to the first opening and the pressure sensor 10 at the position corresponding to the second opening in sequence, and then flows out through the air outlet joint 5.

[0051] It should be noted that the opposed ultrasonic probes are adopted in this embodiment, including a transmitter and a receiver, and the two continuously maintain.

[0052] And it should be noted that only a sensor chip is correspondingly arranged at the opening in this embodiment, and other components are installed on the back of the circuit board 1.

[0053] In summary, the ultrasonic oxygen sensor of this embodiment has the following effective effects:

[0054] 1) The ultrasonic oxygen sensor of this embodiment is internally equipped with a temperature and humidity sensor 9 and a pressure sensor 10, which can calibrate the oxygen concentration using temperature and humidity data and pressure data, improving the accuracy of oxygen concentration measurement; at the same time, by integrating the temperature and humidity sensor 9 and the pressure sensor 10 internally, the volume of the ultrasonic oxygen sensor is effectively reduced, the integration degree is improved, and a stable measurement environment can be provided for oxygen concentration detection;

[0055] 2) In the ultrasonic oxygen sensor of this embodiment, the ultrasonic pipe fitting is provided with a first opening and a second opening at a certain distance. The first opening corresponds to the temperature and humidity sensor 9 on the circuit board 1, and the second opening corresponds to the pressure sensor 10 on the circuit board 1. This setting can avoid the problem of mutual interference between the temperature and humidity sensor 9 and the pressure sensor 10, effectively ensuring the measurement accuracy of the ultrasonic oxygen sensor.

[0056] In a preferred embodiment, referring to Figure 1 、 Figure 3 、 Figure 4 and Figure 5 , the ultrasonic oxygen sensor further includes a first base 6a and a second base 6b. The ultrasonic pipe fitting is installed on the circuit board 1 through the first base 6a and the second base 6b; a first channel 601 adapted to the first opening is provided on the first base 6a, a second channel adapted to the second opening is provided on the second base 6b, and both the first channel 601 and the second channel are internally connected to the gas pipeline 2.

[0057] In this embodiment, the ultrasonic oxygen sensor includes a circuit board 1, an ultrasonic pipe fitting, a first base 6a, and a second base 6b corresponding to the first base 6a. The ultrasonic pipe fitting is horizontally installed in the two bases, and the two bases are fixedly installed on the circuit board 1.

[0058] A first channel 601 is provided on the first base 6a. The shape, size, etc. of the first channel 601 are all adapted to the first opening and extend into the gas pipeline. At this time, the temperature and humidity sensor 9 is correspondingly installed in the first channel 601. When the gas in the gas pipeline 2 flows into the first channel 601, the temperature and humidity of the oxygen can be detected through the temperature and humidity sensor 9 in the first channel 601.

[0059] A second channel is provided on the second base 6b. The shape, size, etc. of the second channel are all adapted to the second opening and extend into the gas pipeline. At this time, the pressure sensor is correspondingly installed in the second channel. When the gas in the gas pipeline 2 flows into the second channel, the oxygen pressure can be detected through the pressure sensor 10 in the second channel.

[0060] In a preferred embodiment, referring to Figure 1 、Figure 4 and Figure 5 A groove adapted to the gas pipeline 2 is provided in the middle of the first base 6a and the second base 6b respectively.

[0061] In this embodiment, the inner diameter of the groove in the middle of the two bases is the same as the outer diameter of the gas pipeline 2, and the depth of the groove in the middle of the two bases is greater than half of the diameter of the gas pipeline 2. Preferably, the depth of the groove is two-thirds of the diameter of the gas pipeline 2.

[0062] It can be understood that by providing a groove adapted to the gas pipeline 2 on the base of this embodiment, the gas pipeline 2 can be stably installed in the base, and at the same time, the gas pipeline 2 can be prevented from directly contacting the circuit board 1, playing a role in protecting the circuit board 1.

[0063] In a preferred embodiment, referring to Figure 4 and Figure 5 Screw mounting holes 602 are provided on both sides of the first base 6a and the second base 6b respectively.

[0064] In this embodiment, screw mounting holes 602 are provided on both sides of the two bases. Correspondingly, positioning holes corresponding to the screw mounting holes 602 are provided on the circuit board 1, so as to achieve precise fixation of the two bases and the circuit board 1.

[0065] In a preferred embodiment, referring to Figure 2 and Figure 6 A voltage converter 11, a first ultrasonic driver 12a, a second ultrasonic driver 12b and a power connector 13 are further provided on the circuit board 1; the power connector 13 is connected to the input end of the voltage converter 11, and the output end of the voltage converter 11 is respectively connected to the power supply ends of the controller 8, the temperature and humidity sensor 9, the pressure sensor 10, the first ultrasonic driver 12a and the second ultrasonic driver 12b; the controller 8 is connected to the first terminal 7a through the first ultrasonic driver 12a, and the controller 8 is connected to the second terminal 7b through the second ultrasonic driver 12b.

[0066] In this embodiment, the circuit board 1 includes, but is not limited to, a controller 8, a temperature and humidity sensor 9, a pressure sensor 10, a voltage converter 11, two ultrasonic drivers, a power connector 13, and two terminals. Among them, the power connector 13 is used to connect to a 12V DC power supply; the input end of the voltage converter 11 is connected to the fourth pin of the power connector 13, and the voltage converter 11 is used to convert the 12V DC power supply into a 3.3V first voltage source to supply power to the controller 8, the temperature and humidity sensor 9, the pressure sensor 10, and the two ultrasonic drivers; the signal output end of the controller 8 is connected to the signal input end of the ultrasonic driver, and the controller 8 is used to output a pulse control signal to control the ultrasonic driver; the voltage output end of the ultrasonic driver is connected to the ultrasonic probe through the terminal, and the ultrasonic driver is used to output a voltage signal under the control of the pulse control signal and transmit the voltage signal to the ultrasonic probe to drive the ultrasonic probe to generate ultrasonic waves.

[0067] In a preferred embodiment, referring to Figure 2 and Figure 6 , the voltage converter 11 includes a voltage regulator chip U2, a TVS diode D1, a second capacitor C2, and a third capacitor C3. The input end of the voltage regulator chip U2 is grounded through the TVS diode D1 and the third capacitor C3 respectively, the output end of the voltage regulator chip U2 is grounded through the second capacitor C2, and the output end of the voltage regulator chip U2 is used to output the first voltage source.

[0068] In this embodiment, the voltage regulator chip U2 is used to convert a 12V voltage into a 3.3V voltage; the TVS diode D1 (i.e., transient voltage suppression diode) is used to prevent the voltage regulator chip U2 from being damaged by instantaneous overvoltage and plays a role in protecting the voltage regulator chip U2; the second capacitor C2 and the third capacitor C3 are both filter capacitors, which are used to filter out unnecessary AC components in the DC power supply to make the direct current smoother. Preferably, the voltage regulator chip U2 adopts an AMS1117 model chip, the breakdown voltage of the TVS diode D1 is 12V, and the capacitance values of the second capacitor C2 and the third capacitor C3 are both 10uF.

[0069] In a preferred embodiment, referring to Figure 2 and Figure 6 , the controller 8 includes a main control chip U1 and a first capacitor C1, and the power supply end of the main control chip U1 is grounded through the first capacitor C1.

[0070] In this embodiment, the main control chip U1 can adopt a chip of model STM32G030F6P6, which includes a serial port clock terminal SCL, a serial port data terminal SDA, a first signal output terminal T_SIN, a second signal output terminal T_SI, a power supply terminal, etc. And the power supply terminal of the main control chip U1 is connected to the output terminal of the voltage converter 11 and grounded through a first capacitor C1 at the same time to prevent high-frequency noise from interfering with the controller 8. Preferably, the capacitance value of the first capacitor C1 is 100 nF.

[0071] In a preferred embodiment, referring to Figure 2 and Figure 6 , the temperature and humidity sensor 9 includes a temperature and humidity sensor chip U3 and a fifth capacitor C5; the temperature and humidity sensor chip U3 is communicatively connected to the main control chip U1 through an I2C interface, and the power supply terminal of the temperature and humidity sensor chip U3 is grounded through the fifth capacitor C5.

[0072] In this embodiment, the humidity sensor chip U3 can adopt a chip of model SHT40-AD1B-R2, which includes an SDA pin, an SCL pin, a power supply terminal, etc. Among them, the SDA pin of the humidity sensor chip U3 is connected to the serial port data terminal of the main control chip U1, and the SCL pin of the humidity sensor chip U3 is connected to the serial port clock terminal of the main control chip U1 to realize I2C communication between the humidity sensor chip U3 and the main control chip U1. And the power supply terminal of the humidity sensor chip U3 is connected to the output terminal of the voltage converter 11 and grounded through a fifth capacitor C5 at the same time to prevent high-frequency noise from interfering with the temperature and humidity sensor 9. Preferably, the capacitance values of the fifth capacitor C5 and the first capacitor C1 are equal, both being 100 nF.

[0073] In a preferred embodiment, referring to Figure 2 and Figure 6 , the pressure sensor 10 includes a pressure sensor chip U4, a first resistor R1, a second resistor R2, a third resistor R3, and a fourth capacitor C4; the power supply terminal of the pressure sensor chip U4 is grounded through the fourth capacitor C4, the clock line pin SCL of the pressure sensor chip U4 is connected to the first voltage source through the second resistor R2, the data line pin SDL of the pressure sensor chip U4 is connected to the first voltage source through the third resistor R3, and the serial data output pin of the pressure sensor chip U4 is grounded through the first resistor R1; the pressure sensor chip U4 is communicatively connected to the main control chip U1 through the clock line pin SCL and the data line pin SDL.

[0074] In this embodiment, the pressure sensor chip U4 can adopt a chip of model LPS22HBTR, which includes a data line pin SDA, a clock line pin SCL, a serial data output pin SDO, an enable pin CS, a power supply terminal, etc. Among them, the data line pin of the pressure sensor chip U4 is connected to the serial port data terminal of the main control chip U1, and the data line pin of the pressure sensor chip U4 is connected to the serial port data terminal of the main control chip U1 to realize I2C communication between the pressure sensor chip U4 and the main control chip U1. Secondly, the data line pin and the clock line pin of the pressure sensor chip U4 are respectively connected to a 3.3V DC power supply through a pull-up resistor (i.e., the second resistor R2 or the third resistor R3), and the two lines are controlled to be in a high-level state by the pull-up resistor; the serial data output pin SDO of the pressure sensor chip U4 is grounded through the first resistor R1 to set the I2C communication address of the pressure sensor chip U4; the enable pin CS of the pressure sensor chip U4 is connected to a 3.3V DC power supply, and the power supply terminal of the pressure sensor chip U4 is connected to the output terminal of the voltage converter 11 and grounded through the fourth capacitor C4 at the same time to prevent high-frequency noise from interfering with the pressure sensor 10. Preferably, the resistance value of the first resistor R1 is 10KΩ, the resistance values of the second resistor R2 and the third resistor R3 are equal, both are 4.7KΩ, and the capacitance values of the fourth capacitor R4, the fifth capacitor C5, and the first capacitor C1 are equal, all are 100nF.

[0075] In a preferred embodiment, referring to Figure 2 and Figure 6 , the first ultrasonic driver 12a includes a first driving chip U5; the signal input terminal of the first driving chip U5 is connected to the first signal output terminal of the main control chip U1, and the voltage output terminal of the first driving chip U5 is connected to the first ultrasonic probe 3a through the first terminal 7a. The second ultrasonic driver 12b includes a second driving chip U6; the signal input terminal of the second driving chip U6 is connected to the second signal output terminal of the main control chip U1, and the voltage output terminal of the second driving chip U6 is connected to the second ultrasonic probe 3b through the second terminal 7b.

[0076] In this embodiment, the first driving chip U5 and the second driving chip U6 can adopt a customized driving chip or a chip of model MC33151. For the customized driving chip, it includes a power supply positive pin, a power supply negative pin, a pulse control signal transceiver pin (i.e., the signal input terminal), and an ultrasonic probe connection pin (i.e., the voltage output terminal).

[0077] The above are the preferred embodiments of the present utility model. It should be noted that for those of ordinary skill in the art, several improvements and refinements can be made without departing from the principle of the present utility model, and these improvements and refinements are also regarded as the protection scope of the present utility model.

Claims

1. An ultrasonic oxygen sensor, characterized in that, Comprising: A circuit board and an ultrasonic pipe fitting mounted above the circuit board; A controller, a temperature and humidity sensor, a pressure sensor, a first terminal and a second terminal are provided on the circuit board; the controller is respectively connected to the temperature and humidity sensor, the pressure sensor, the first terminal and the second terminal; The ultrasonic pipe fitting includes a gas pipeline, a first ultrasonic probe, a second ultrasonic probe, an air inlet joint and an air outlet joint. The first ultrasonic probe and the second ultrasonic probe are respectively provided at both ends of the gas pipeline. The first ultrasonic probe is connected to the first terminal, and the second ultrasonic probe is connected to the second terminal; the air inlet joint and the air outlet joint are respectively provided on one side of the gas pipeline; a first opening and a second opening are provided at the bottom of the gas pipeline, the first opening corresponds to the temperature and humidity sensor, and the second opening corresponds to the pressure sensor.

2. The ultrasonic oxygen sensor according to claim 1, characterized in that, The ultrasonic oxygen sensor further includes a first base and a second base. The ultrasonic pipe fitting is mounted on the circuit board through the first base and the second base; a first channel adapted to the first opening is provided on the first base, and a second channel adapted to the second opening is provided on the second base, and both the first channel and the second channel are connected to the inside of the gas pipeline.

3. The ultrasonic oxygen sensor according to claim 2, characterized in that, Grooves adapted to the gas pipeline are provided in the middle of the first base and the second base.

4. The ultrasonic oxygen sensor according to claim 3, wherein Screw mounting holes are provided on both sides of the first base and the second base.

5. The ultrasonic oxygen sensor according to claim 1, wherein A voltage converter, a first ultrasonic driver, a second ultrasonic driver and a power supply joint are further provided on the circuit board; the power supply joint is connected to the input end of the voltage converter, and the output end of the voltage converter is respectively connected to the power supply ends of the controller, the temperature and humidity sensor, the pressure sensor, the first ultrasonic driver and the second ultrasonic driver; the controller is connected to the first terminal through the first ultrasonic driver, and the controller is connected to the second terminal through the second ultrasonic driver.

6. The ultrasonic oxygen sensor according to claim 5, wherein The voltage converter includes a voltage stabilizing chip, a TVS tube, a second capacitor and a third capacitor. The input end of the voltage stabilizing chip is respectively grounded through the TVS tube and the third capacitor, the output end of the voltage stabilizing chip is grounded through the second capacitor, and the output end of the voltage stabilizing chip is used to output a first voltage source.

7. The ultrasonic oxygen sensor according to claim 6, wherein, The controller includes a main control chip and a first capacitor. The power supply end of the main control chip is grounded through the first capacitor.

8. The ultrasonic oxygen sensor according to claim 7, characterized in that, The temperature and humidity sensor includes a temperature and humidity sensor chip and a fifth capacitor; the temperature and humidity sensor chip is communicatively connected to the main control chip through an I2C interface, and the power supply end of the temperature and humidity sensor chip is grounded through the fifth capacitor.

9. The ultrasonic oxygen sensor according to claim 8, characterized in that, The pressure sensor includes a pressure sensor chip, a first resistor, a second resistor, a third resistor, and a fourth capacitor; the power supply terminal of the pressure sensor chip is grounded through the fourth capacitor, the clock line pin of the pressure sensor chip is connected to the first voltage source through the second resistor, the data line pin of the pressure sensor chip is connected to the first voltage source through the third resistor, and the serial data output pin of the pressure sensor chip is grounded through the first resistor; the pressure sensor chip is communicatively connected to the main control chip through the clock line pin and the data line pin.

10. The ultrasonic oxygen sensor according to claim 9, characterized in that, The first ultrasonic driver includes a first driver chip; the signal input terminal of the first driver chip is connected to the first signal output terminal of the main control chip, and the voltage output terminal of the first driver chip is connected to the first ultrasonic probe through the first terminal. The second ultrasonic driver includes a second driver chip; the signal input terminal of the second driver chip is connected to the second signal output terminal of the main control chip, and the voltage output terminal of the second driver chip is connected to the second ultrasonic probe through the second terminal.

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