阅读说明：本技术 一种用于检测空氧混合器氧气浓度的装置 (Device for detecting oxygen concentration of air-oxygen mixer ) 是由 林俊龙 卢伟升 陈伟俊 庄卓伟 张旭 于 2021-04-30 设计创作，主要内容包括：本发明涉及气体浓度检测技术领域,具体涉及一种用于检测空氧混合器氧气浓度的装置,所述的装置包括中央处理器、设备面板和气体回路,所述气体回路连接气源和空氧混合器接头；所述气体回路设置为两路,第一路气体回路与空氧混合器的空气接头相连,第二路气体回路与空氧混合器的氧气接头相连；所述两路气体回路均设置有气体质量流量计；所述的设备面板上设置有氧浓度数显装置；所述的氧浓度数显装置、气体质量流量计与中央处理器电连接；两路气体回路的气体质量流量计将流量数值发送到中央处理器,中央处理器计算出氧气浓度值并将其输出到氧浓度数显装置上。该装置测试时气体流量波动对数值影响不大,且反应速度快,测试效率高。(The invention relates to the technical field of gas concentration detection, in particular to a device for detecting the oxygen concentration of an air-oxygen mixer, which comprises a central processing unit, an equipment panel and a gas loop, wherein the gas loop is connected with a gas source and an air-oxygen mixer joint; the gas loop is divided into two paths, the first path of gas loop is connected with an air joint of the air-oxygen mixer, and the second path of gas loop is connected with an oxygen joint of the air-oxygen mixer; the two gas loops are provided with gas mass flowmeters; the equipment panel is provided with an oxygen concentration digital display device; the oxygen concentration digital display device and the gas mass flowmeter are electrically connected with the central processing unit; the gas mass flow meters of the two gas loops send the flow numerical values to the central processing unit, and the central processing unit calculates the oxygen concentration value and outputs the oxygen concentration value to the oxygen concentration digital display device. When the device is used for testing, the gas flow fluctuation has little influence on the numerical value, the reaction speed is high, and the testing efficiency is high.)

1. The device for detecting the oxygen concentration of the air-oxygen mixer is characterized by comprising a central processing unit, an equipment panel and a gas loop, wherein the gas loop is connected with a gas source and an air-oxygen mixer joint; the gas loop is divided into two paths, the first path of gas loop is connected with an air joint of the air-oxygen mixer, and the second path of gas loop is connected with an oxygen joint of the air-oxygen mixer; the two gas loops are provided with gas mass flowmeters; the central processing unit comprises a single chip microcomputer and an MAX3232 chip; the equipment panel is provided with an oxygen concentration digital display device; the oxygen concentration digital display device and the gas mass flowmeter are electrically connected with the central processing unit; the gas mass flow meters of the two gas loops send flow values to the MAX3232 chip, the MAX3232 chip converts the flow values into level signals and sends the level signals to the single chip microcomputer, the single chip microcomputer calculates oxygen concentration values according to a calculation formula and outputs the oxygen concentration values to the oxygen concentration digital display device, and the calculation formula is as follows:

oxygen concentration value% (S1 × 21%/M1 + S2 × 100%/M2)/(S1/M1 + S2/M2),

wherein M1 is the air molar mass, M2 is the oxygen molar mass, S1 is the flow rate of the gas mass flowmeter in the first gas loop, and S2 is the flow rate of the gas mass flowmeter in the second gas loop.

2. The apparatus of claim 1, wherein the gas circuit comprises a filter, a control valve, a pressure regulating valve, a gas mass flow meter and a joint; the filter is connected with an air source, and the joint is connected with the joint of the air-oxygen mixer through a pipeline.

3. The apparatus as claimed in claim 2, wherein the two gas circuits are each provided with at least two control valves, and the pressure regulating valve is disposed between the two control valves.

4. The apparatus according to claim 3, wherein the pressure regulating valve is connected to a digital pressure gauge, and the digital pressure gauge is disposed on a panel of the apparatus.

5. The apparatus of claim 4, wherein the gas circuit is further provided with a pressure gauge behind the filter, and the pressure gauge is arranged on a panel of the equipment.

6. The apparatus as claimed in claim 5, wherein the air source is an air source, and the air source is divided into two gas circuits after passing through a filter and a pressure gauge: the first path of gas loop passes through the first control valve, the pressure regulating valve, the second control valve and the first gas mass flowmeter and is connected with an air joint of the air-oxygen mixer through a pipeline for joints; and the second gas loop passes through the fourth control valve, the pressure regulating valve, the fifth control valve and the gas mass flowmeter II and is connected with an oxygen joint of the air-oxygen mixer through a pipeline for joints.

7. The apparatus according to claim 5, wherein the air source of the first air circuit is an air source, and the air source passes through the filter and the pressure gauge, passes through the first control valve, the pressure regulating valve, the second control valve and the first gas mass flowmeter, and is connected to the air connector of the air-oxygen mixer through a connector by a pipeline; and the gas source of the second gas loop is an oxygen gas source, and the oxygen gas source flows through the filter and the pressure gauge, then passes through the third control valve, the fourth control valve, the pressure regulating valve, the fifth control valve and the second gas mass flowmeter, and is connected with an oxygen joint of the air-oxygen mixer through a pipeline for a joint.

8. The apparatus as claimed in claim 6 or 7, wherein the control valve is a hand-operated valve; the fourth control valve is a three-position four-way hand-operated valve, and the other control valves are two-position four-way hand-operated valves.

Technical Field

The invention relates to the technical field of gas concentration detection, in particular to a device for detecting the oxygen concentration of an air-oxygen mixer.

Background

The existing oxygen concentration detection device of the air-oxygen mixer uses pure oxygen and air to be mixed, and generally adopts an oxygen concentration tester with an oxygen battery to carry out concentration test. However, the testing method depends heavily on oxygen, and not only is the cost of testing price high by using oxygen; the oxygen battery has low reaction speed and is sensitive to the gas flow, and the gas flow fluctuation has large influence on the numerical value during testing and has low numerical value stability; and the requirement on oxygen concentration is high, and the requirement on the safety protection of oxygen is high.

Disclosure of Invention

The invention aims to overcome the defects of oxygen concentration test in the air-oxygen mixer in the prior art, and provides the device for detecting the oxygen concentration of the air-oxygen mixer.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a device for detecting the oxygen concentration of an air-oxygen mixer comprises a central processing unit, an equipment panel and a gas loop, wherein the gas loop is connected with a gas source and an air-oxygen mixer joint; the gas loop is divided into two paths, the first path of gas loop is connected with an air joint of the air-oxygen mixer, and the second path of gas loop is connected with an oxygen joint of the air-oxygen mixer; the two gas loops are provided with gas mass flowmeters; the central processing unit comprises a single chip microcomputer and an MAX3232 chip; the equipment panel is provided with an oxygen concentration digital display device; the oxygen concentration digital display device and the gas mass flowmeter are electrically connected with the central processing unit; the gas mass flow meters of the two gas loops send flow values to the MAX3232 chip, the MAX3232 chip converts the flow values into level signals and sends the level signals to the single chip microcomputer, the single chip microcomputer calculates oxygen concentration values according to a calculation formula and outputs the oxygen concentration values to the oxygen concentration digital display device, and the calculation formula is as follows:

oxygen concentration value% (S1 × 21%/M1 + S2 × 100%/M2)/(S1/M1 + S2/M2),

wherein M1 is the air molar mass, M2 is the oxygen molar mass, S1 is the flow rate of the gas mass flowmeter in the first gas loop, and S2 is the flow rate of the gas mass flowmeter in the second gas loop.

Further, the gas circuit comprises a filter, a control valve, a pressure regulating valve, a gas mass flowmeter and a joint; the filter is connected with an air source, and the joint is connected with the joint of the air-oxygen mixer through a pipeline.

Preferably, the filter is an AFM20 filter cup. The input gas source is filtered to remove water and impurities.

Preferably, the two gas circuits are respectively provided with at least two control valves, and the pressure regulating valve is arranged between the two control valves.

Preferably, the pressure regulating valve is connected with a digital display pressure gauge, and the digital display pressure gauge is arranged on the equipment panel.

Preferably, the gas loop is further provided with a pressure gauge behind the filter, and the pressure gauge is arranged on the equipment panel.

Furthermore, the air source is an air source, and the air source is divided into two paths of air loops after flowing through the filter and the pressure gauge: the first path of gas loop passes through the first control valve, the pressure regulating valve, the second control valve and the first gas mass flowmeter and is connected with an air joint of the air-oxygen mixer through a pipeline for joints; and the second gas loop passes through the fourth control valve, the pressure regulating valve, the fifth control valve and the gas mass flowmeter II and is connected with an oxygen joint of the air-oxygen mixer through a pipeline for joints.

According to the scheme, an air source is used for replacing a pure oxygen source to detect the oxygen concentration of an air-oxygen mixer, and after entering a device, a compressed air source is divided into two paths and connected to the detection device and connected with the air-oxygen mixer; the central processing unit reads the flow of the two paths of gases and converts the flow into a corresponding oxygen concentration value through the proportional value of the two paths of gases.

Furthermore, the air source of the first path of air loop is an air source, and the air source flows through the filter and the pressure gauge, then passes through the first control valve, the pressure regulating valve, the second control valve and the first gas mass flowmeter, and is connected with an air joint of the air-oxygen mixer through a joint by a pipeline; and the gas source of the second gas loop is an oxygen gas source, and the oxygen gas source flows through the filter and the pressure gauge, then passes through the third control valve, the fourth control valve, the pressure regulating valve, the fifth control valve and the second gas mass flowmeter, and is connected with an oxygen joint of the air-oxygen mixer through a pipeline for a joint.

Preferably, the control valve is a hand-operated valve; the fourth control valve is a three-position four-way hand-operated valve, and the other control valves are two-position four-way hand-operated valves.

Preferably, the oxygen concentration digital display device is a four-position common anode nixie tube.

Has the advantages that:

1. the invention has the advantages of exquisite structure, reasonable design and long service life.

2. The device integrates two testing methods: the air oxygen mixer is tested by using air instead of pure oxygen as input gas, the oxygen concentration value of the air oxygen mixer is tested, the air oxygen mixer has the characteristics of low cost, no need of pure oxygen, high sensitivity, high precision and the like, is applied to the test of the air oxygen mixer, and aims to reduce the test cost and improve the test efficiency. Secondly, testing an air-oxygen mixer by using pure oxygen and air; the oxygen concentration calibration device can rapidly complete the oxygen concentration calibration work in the air-oxygen mixer, and is convenient and safe to use, simple to operate and accurate in inspection.

Drawings

FIG. 1 is a schematic structural diagram of an apparatus for detecting oxygen concentration in an air-oxygen mixer according to the present invention;

FIG. 2 is a circuit diagram of the single chip microcomputer in the invention;

FIG. 3 is a circuit diagram of a MAX3232 chip in the present invention;

FIG. 4 is a circuit diagram of a power supply module (+5V) in the present invention;

FIG. 5 is a circuit diagram of a power supply module (-5V) in the present invention;

FIG. 6 is a circuit diagram of a gas mass flow meter according to the present invention; wherein J2 is gas mass flow meter I, J3 is gas mass flow meter II;

FIG. 7 is a circuit diagram of a bit select module according to the present invention;

FIG. 8 is a circuit diagram of a nixie tube display module (i.e., an oxygen concentration digital display device) according to the present invention;

FIG. 9 is a circuit diagram of a pressure signal processing module of the first gas loop of the present invention;

FIG. 10 is a circuit diagram of a pressure signal processing module of the second gas loop of the present invention;

description of reference numerals: 1. a first control valve; 2. a second control valve; 3. a third control valve; 4. a fourth control valve; 5. a fifth control valve; 6. a first gas mass flow meter; 7. and a second gas mass flow meter.

Detailed Description

The present invention will be described in detail with reference to specific examples.

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

Example 1:

an apparatus for detecting oxygen concentration of an air-oxygen mixer as shown in fig. 1, the apparatus comprises a central processing unit, an equipment panel and a gas loop, wherein the gas loop is connected with a gas source and an air-oxygen mixer joint; the gas loop is divided into two paths, the first path of gas loop is connected with an air joint of the air-oxygen mixer, and the second path of gas loop is connected with an oxygen joint of the air-oxygen mixer; the two gas loops are provided with gas mass flowmeters; the central processing unit comprises a single chip microcomputer and an MAX3232 chip; the equipment panel is provided with an oxygen concentration digital display device; the oxygen concentration digital display device and the gas mass flowmeter are electrically connected with the central processing unit; the gas mass flow meters of the two gas loops send flow values to the MAX3232 chip, the MAX3232 chip converts the flow values into level signals and sends the level signals to the single chip microcomputer, the single chip microcomputer calculates oxygen concentration values according to a calculation formula and outputs the oxygen concentration values to the oxygen concentration digital display device, and the calculation formula is as follows:

oxygen concentration value% (S1 × 21%/M1 + S2 × 100%/M2)/(S1/M1 + S2/M2),

wherein M1 is the air molar mass, M2 is the oxygen molar mass, S1 is the flow rate of the gas mass flowmeter in the first gas loop, and S2 is the flow rate of the gas mass flowmeter in the second gas loop.

Furthermore, the gas loop is provided with a filter, a control valve, a pressure regulating valve, a gas mass flowmeter and a joint; the filter is connected with an air source, and the joint is connected with the joint of the air-oxygen mixer through a pipeline.

Preferably, the filter is an AFM20 filter cup. The input gas source is filtered to remove water and impurities.

Preferably, the two gas circuits are respectively provided with at least two control valves, and the pressure regulating valve is arranged between the two control valves.

Preferably, the pressure regulating valve is connected with a digital display pressure gauge, and the digital display pressure gauge is arranged on the equipment panel.

Preferably, the gas loop is further provided with a pressure gauge behind the filter, and the pressure gauge is arranged on the equipment panel.

Furthermore, the air source is an air source, and the air source is divided into two paths of air loops after flowing through the filter and the pressure gauge: the first path of gas loop passes through a first control valve 1, a pressure regulating valve, a second control valve 2 and a gas mass flowmeter 6 and is connected with an air joint of an air-oxygen mixer through a joint pipeline; the second path of gas loop passes through a fourth control valve 4, a pressure regulating valve, a fifth control valve 5 and a second gas mass flowmeter 7 and is connected with an oxygen joint of the air-oxygen mixer through a joint pipeline.

Furthermore, the air source of the first path of air loop is an air source, and the air source flows through the filter and the pressure gauge, then passes through the first control valve 1, the pressure regulating valve, the second control valve 2 and the first gas mass flowmeter 6, and is connected with an air joint of the air-oxygen mixer through a joint pipeline; and the gas source of the second gas loop is an oxygen gas source, and the oxygen gas source flows through the filter and the pressure gauge, passes through the third control valve 3, the fourth control valve 4, the pressure regulating valve, the fifth control valve 5 and the gas mass flowmeter II 7, and is connected with an oxygen joint of the air-oxygen mixer through a joint pipeline.

Preferably, the control valve is a hand-operated valve; the fourth control valve is a three-position four-way hand-operated valve, and the other control valves are two-position four-way hand-operated valves.

As shown in fig. 2, in order to ensure that the single chip microcomputer U8 works normally and accurately, the 8 th pin of the single chip microcomputer U8 is connected with the crystal oscillator Y1 and the capacitor C19, and the other end of the capacitor C19 is connected with the power ground; the 9 th pin of the singlechip is connected with the other end of the crystal oscillator Y1 and the capacitor C21, and the other end of the capacitor C21 is connected with a power ground; the 11 th pin of the singlechip is connected with a capacitor C22 and a 2 nd pin of a power reference chip U11, the 1 st pin of the power reference chip U11 is connected with a +5V direct-current power supply, the 3 rd pin of the power reference chip U11 is connected with a power ground, and the capacitor C23 is respectively connected with the +5V direct-current power supply and two ends of the power ground; the 12 th pin of the single chip microcomputer is connected with an inductor L3, a capacitor E5 and a capacitor C28, the other ends of the capacitor E5 and the capacitor C28 are connected with a power ground, and the inductor L3 is connected with a direct-current power supply + 5V; the 14 th pin of the singlechip is connected with a capacitor C30 to a DC power supply +5V, and the other end of the capacitor C30 is connected with the power ground.

Other pins of the single chip microcomputer shown in fig. 2-8 are respectively connected with a MAX3232 chip, a bit selection module, a nixie tube display module, a pressure signal processing module and a power supply module; the power supply module provides a required power supply for the central processing unit; the bit selection module controls the lightening nixie tube to refresh bits and different IO ports to update the numbers; the nixie tube display module is a four-position common-anode nixie tube and displays the oxygen concentration value calculated by the single chip microcomputer; the pressure signal processing module is used for constant-current power supply and pressure signal amplification of the pressure sensor.

Pure oxygen and air test air-oxygen mixer test principle:

the input air source removes moisture and impurities through a filter, a pressure gauge displays the pressure value of the air source, the pressure value is switched to the next-stage loop through a first control valve 1, the air loop is switched to the next-stage loop through a pressure regulating valve after being subjected to pressure regulation, and the air loop is led out to an air inlet of the measured air-oxygen mixer through a first gas mass flowmeter 6.

The input oxygen removes moisture and impurities through a filter, a pressure gauge displays a gas source pressure value, the pressure value is switched to a next-stage loop through a third control valve 3 and a fourth control valve 4, the oxygen loop is switched to the next-stage loop through a fifth control valve 5 after being subjected to pressure regulation through a pressure regulating valve, and the oxygen loop is led out to an oxygen inlet of the measured air-oxygen mixer through a second gas mass flow meter 7. During testing, the air output pipeline and the oxygen output pipeline are respectively connected to the tested air-oxygen mixer, the oxygen concentration value of the air-oxygen mixer is adjusted, the corresponding oxygen concentration value can be quickly read from the equipment panel, and the oxygen concentration value is calibrated through an external oxygen concentration tester.

Air test air-oxygen mixer test principle:

the third control valve 3 is closed, the first control valve 1, the fourth control valve 4 and the fifth control valve 5 are opened, and the air flows through the two gas mass flow meters and is output to the outside of the device. During testing, the air output pipeline and the oxygen output pipeline of the gas loop are respectively and correspondingly connected to the tested air-oxygen mixer, the oxygen concentration value of the air-oxygen mixer is adjusted, the corresponding oxygen concentration value can be read from the equipment panel of the device, and the oxygen concentration value of the air-oxygen mixer is quickly calibrated.

Finally, it should be noted that: it should be understood that the above examples are only for clearly illustrating the present invention and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications of the invention may be made without departing from the scope of the invention.