An oxygen-free device for SF6 mixed gas detector

Abstract

The present invention discloses an oxygen-free device for an SF6 mixed gas detector, comprising a first pipe, a sealing device disposed outside the first pipe, an oxygen sensor body disposed within the sealing device, a through-hole formed in the inner wall of the first pipe, the through-hole communicating with the inner cavity of the sealing device, a piston slidingly disposed within the first pipe and in contact with the pipe wall, the piston sealing the through-hole in a non-detection state. In the present invention, a piston is slidably connected within the first pipe, and during detection, the piston can be moved to place the first pipe and the sealing device in a conductive state, thereby allowing oxygen to enter the sealing device for detection. In a non-detection state, the piston can be moved to seal the through-hole, thereby preventing oxygen from entering and affecting the detection life of the oxygen sensor.

Description

Technical Field

[0001] The present invention relates to the technical field of mixed gas detectors, and more particularly to an oxygen-free device for SF6 mixture detectors. Background Art

[0002] The core component of an electrochemical oxygen analyzer is an electrochemical oxygen sensor. A typical electrochemical oxygen sensor consists of a sensing electrode (or working electrode) and a counter electrode (lead electrode), separated by a thin layer of electrolyte. The gas to be detected first passes through a small capillary opening in the sensor, then diffuses through a hydrophobic membrane, ultimately reaching the electrode surface. The sensor's structural design ensures that an appropriate amount of gas enters the sensor to react with the sensing electrode to generate a sufficient electrical signal, while simultaneously preventing electrolyte leakage from the sensor. Gas that diffuses through the hydrophobic membrane into the sensor undergoes an oxidation / reduction reaction at the sensing electrode, generating a current proportional to the oxygen concentration between the cathode and anode. This current is detected to determine the oxygen concentration in the gas.

[0003] The SF6 mixed gas detector can detect the content of SF6 and O2 in the detected gas. The detection of O2 content requires the use of an electrochemical oxygen analyzer. Since the O2 content in the detected gas is relatively low, in order to ensure that the error of O2 detection does not exceed 0.1%, the detection range of the O2 sensor needs to be controlled within the range of 0%-1%. The concentration of O2 in the air reaches about 21%, so if the O2 sensor is placed in the air, the sensor will be in an overload state for a long time and damaged. Therefore, it is necessary to design a sealed oxygen-free structure for the O2 sensor to isolate the O2 sensor from the outside world when not in use to prevent internal consumption from damaging the service life of the O2 sensor.

[0004] See Figure 1 The existing technology generally installs an oxygen sensor protection valve and a bypass regulating valve, first connects the sample gas and exhaust gas receiving device, opens the bypass regulating valve when not testing, uses the sample gas to purge the pipeline for 3 minutes to 5 minutes, then opens the oxygen sensor protection valve and performs testing. After the test is completed, it is purged with dry nitrogen for 3 minutes to 5 minutes, and then the oxygen sensor protection valve is closed to protect the oxygen sensor.

[0005] However, it circulates gas by repeatedly opening and closing valves, which is cumbersome and inconvenient; it requires the use of sample gas and dry nitrogen for purging, resulting in unnecessary waste; after closing the oxygen sensor protection valve, there is still gas remaining inside, which fails to achieve the effect of sealing and isolating oxygen. Summary of the Invention

[0006] The technical problem to be solved by the present invention is how to achieve sealing of the oxygen sensor in a non-detection state, isolate it from external gases, and prevent oxygen from entering and affecting its service life.

[0007] The present invention solves the above-mentioned technical problems through the following technical means: an oxygen-eliminating device for use in a SF6 and N2 mixed gas detector, comprising a first pipe and a sealing device disposed outside the first pipe, wherein an oxygen sensor body is fixedly sealed within the sealing device, a through-hole is formed in the inner wall of the first pipe and communicates with the inner cavity of the sealing device through the through-hole, a piston is slidably disposed within the first pipe and abuts against the pipe wall, and the piston seals the through-hole in a non-detection state. The through-hole can be sealed in the non-detection state, and the piston is offset from the through-hole during detection.

[0008] A piston is slidably connected in the first pipe. During detection, the piston can be moved to put the first pipe and the sealing device in a conductive state, thereby allowing oxygen to enter the sealing device for detection. In the non-detection state, the piston can be moved to seal the through hole, thereby preventing oxygen from entering and affecting the detection life of the oxygen sensor.

[0009] As a preferred technical solution, the sealing device also includes a sealing shell and a sealing cover. The sealing shell is fixedly connected to the outer wall of the first pipe and is communicated with the first pipe. The sealing shell and the sealing cover are fixedly enclosed and formed into a closed cavity structure.

[0010] As a preferred technical solution, the oxygen sensor body includes a lead electrode, a working electrode, and two electrode pins. The sealing cover is fixedly connected to two electrode pins, and the two electrode pins are respectively connected to metal sheets through leads. The lead electrode and the working electrode are provided in the cavity, and the two metal sheets are located between the lead electrode and the working electrode. An insulating plate is provided between the two metal sheets, and the cavity is filled with electrolyte.

[0011] As a preferred technical solution, it also includes a constant temperature box, which is provided with a first air inlet and a first air outlet. A heating chamber is provided in the constant temperature box, which is connected to the first pipe. A plurality of heating plates are provided on the outside of the heating chamber. The heating effect of the heating plates can be ensured by setting a temperature sensor. By cooperating with the control system, it is ensured that the piston is opened only when the temperature that meets the detection requirements is reached, thereby increasing the reliability and service life of the oxygen sensor detection.

[0012] As a preferred technical solution, an electric telescopic rod is provided on the top of the first pipe, the telescopic end of the electric telescopic rod is fixedly connected to the piston, and the electric telescopic rod drives the piston to move up and down along the inner wall of the first pipe.

[0013] As a preferred technical solution, a temperature sensor is provided on the top of the constant temperature box.

[0014] As a preferred technical solution, it also includes a control system, which is electrically connected to the temperature sensor and the electric telescopic rod.

[0015] As a preferred technical solution, the side wall of the sealing shell bulges outward and is provided with a second air inlet, the second air inlet is provided with a hydrophobic membrane, the sealing shell is fixed to the first pipe by threads, and a rubber pad is provided between the sealing shell and the outer wall of the first pipe.

[0016] The advantages of the present invention are:

[0017] (1) In the present invention, a piston is slidably connected in the first pipe. During detection, the piston can be moved to put the first pipe and the sealing device in a conductive state, thereby allowing oxygen to enter the sealing device for detection. In the non-detection state, the piston can be moved to seal the through hole, thereby preventing oxygen from entering and affecting the detection life of the oxygen sensor.

[0018] (2) In the present invention, the heating effect of the heating plate can be ensured by setting the temperature sensor. By coordinating with the control system, it is ensured that the piston is opened only when the temperature meets the detection requirements, thereby increasing the reliability and service life of the oxygen sensor detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic structural diagram of an oxygen-free device for an SF6 mixed gas detector provided as background technology of the present invention;

[0020] Figure 2 A schematic diagram of the overall structure of an oxygen-free device for an SF6 mixed gas detector provided in an embodiment of the present invention;

[0021] Figure 3 A schematic cross-sectional view of an oxygen-free device for an SF6 mixed gas detector provided in an embodiment of the present invention;

[0022] Figure 4 A schematic structural diagram of a sealing device for an oxygen-free device of an SF6 mixed gas detector provided in an embodiment of the present invention;

[0023] Figure numbers: 1. first air inlet; 2. constant temperature box; 3. first air outlet; 4. heating plate; 5. first pipeline; 6. sealing device; 601. sealing shell; 602. sealing cover; 603. electrode pin; 604. lead electrode; 605. insulating plate; 606. working electrode; 7. electric telescopic rod; 8. piston; 9. temperature sensor; 10. second air inlet. DETAILED DESCRIPTION

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0025] See Figure 2 An oxygen-free device for an SF6 mixed gas detector includes a constant temperature box 2, a first pipe 5, an electric telescopic rod 7, a sealing device 6, a piston 8, and a control system. The top of the first pipe 5 is fixedly connected to the electric telescopic rod 7, the telescopic end of the electric telescopic rod 7 is fixedly connected to the piston 8, the piston 8 is slidably connected to the inner wall of the first pipe 5, an oxygen sensor body is provided in the sealing device 6, a second air inlet 10 is opened on the first pipe 5, and the second air inlet 10 is connected to the inner cavity of the sealing device 6. The control system is electrically connected to the electric telescopic rod 7. The control system controls the piston 8 through the electric telescopic rod 7 to achieve sealing of the through hole in a non-detection state, that is, the piston 8 seals the second air inlet 10.

[0026] See Figure 3 、 Figure 4 The sealing device 6 also includes a sealing shell 601, a sealing cover 602, an electrode pin 603, a lead electrode 604, an insulating plate 605, and a working electrode 606. The side wall of the sealing shell 601 protrudes outward, and the sealing shell 601 is threadedly fixed to the first pipe 5. A rubber pad is also provided between the sealing shell 601 and the outer wall of the first pipe 5. The sealing shell 601 is connected to the first pipe 5. The sealing cover 602 is fixedly connected to the sealing shell 601 by two bolts. The sealing shell 601 and the sealing cover 602 are enclosed and fixed to form a closed cavity structure. The lead electrode 604 and the working electrode 606 are provided in the cavity. Two electrode pins are fixedly connected to the sealing cover 602. 603, the two electrode pins 603 are electrically connected to a metal sheet through a lead wire respectively, and the two metal sheets are located between the working electrode 606 and the lead electrode 604, one of the metal sheets is close to the working electrode 606, and the other metal sheet is close to the lead electrode 604. An insulating plate 605 is arranged between the two metal sheets. In order to prevent the electrodes from short-circuiting, thereby causing a short circuit, the cavity of the insulating plate 605 is filled with electrolyte, and the second air inlet 10 is provided with a hydrophobic membrane to prevent the electrolyte from flowing out, while allowing oxygen to enter, react on the working electrode 606, and extract the current through the electrode pin 603. The electrode pin 603 is electrically connected to the control system.

[0027] See Figure 2The constant temperature box 2 is provided with a first air inlet 1 and a first air outlet 3. A heating chamber is opened in the constant temperature box 2, and the heating chamber is connected to the first pipe 5. A plurality of heating plates 4 are provided on the outside of the heating chamber. A temperature sensor 9 is provided on the top of the constant temperature box 2, and the temperature sensor 9 is electrically connected to the control system.

[0028] Directions:

[0029] S1. Heating stage: The gas to be detected can enter the thermostat 2 from the first air inlet 1 and then be discharged from the first air outlet 3. During the heating stage, the piston 8 is at the bottom of the first pipe 5 and is in contact with the second air inlet 10, so that the oxygen sensor detecting gas from the second air inlet 10 is in a sealed and oxygen-free state. The heating plate 4 can heat the gas to be detected in the thermostat 2, so that the gas to be detected reaches the appropriate detection temperature that meets the requirements of the oxygen sensor body;

[0030] S2, heating stage:

[0031] When the temperature sensor 9 in the thermostat 2 measures that the temperature of the detected gas reaches the detection standard, the control system gives a signal, the electric telescopic rod 7 control unit executes, the electric telescopic rod 7 contracts, and drives the piston 8 in the first pipe 5 to move upward. The piston 8 separates from the second air inlet 10 and extracts part of the detected gas in the thermostat 2 into the first pipe 5 through the pressure difference. The detected gas enters the oxygen sensor body through the second air inlet 10 in the form of diffusion for detection.

[0032] S3, exhaust stage:

[0033] After the detection is completed, the control system gives a signal, the electric telescopic rod 7 is extended, driving the piston 8 to reset, expelling the remaining gas in the first pipe 5, and the wall of the piston 8 is re-fitted with the second air inlet 10, so that the oxygen sensor body returns to the closed and oxygen-free state.

[0034] Repeating steps S2 and S3 can repeatedly detect the oxygen content of the gas to be detected in the constant temperature box 2.

[0035] When the oxygen content does not need to be detected, the piston 8 is in its original state, the heating plate 4 does not need to be turned on, and the gas to be measured can directly pass through the constant temperature box without contacting the oxygen sensor.

[0036] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An oxygen-free device for SF6 mixed gas detector, characterized in that: The invention comprises a first pipe, a sealing device arranged on the outside of the first pipe, and a constant temperature box, wherein an oxygen sensor body is sealed and fixed in the sealing device, a through hole is provided on the inner wall of the first pipe, and the through hole is connected to the inner cavity of the sealing device, a piston is slidably provided in the first pipe and is in contact with the pipe wall, and the piston can seal the through hole in a non-detection state, and the piston is staggered with the through hole during detection, the constant temperature box is provided with a first air inlet and a first air outlet, a heating chamber is provided in the constant temperature box, the heating chamber is connected to the first pipe, and a plurality of heating plates are provided on the outside of the heating chamber.

2. The oxygen-free device for SF6 mixed gas detector according to claim 1, characterized in that: The sealing device further comprises a sealing shell and a sealing cover. The sealing shell is fixedly connected to the outer wall of the first pipe and is communicated with the first pipe. The sealing shell and the sealing cover are fixedly enclosed and form a closed cavity structure.

3. The oxygen-free device for SF6 mixed gas detector according to claim 2, characterized in that: The oxygen sensor body includes a lead electrode, a working electrode, and two electrode pins. The sealing cover is fixedly connected to the two electrode pins, and the two electrode pins are respectively connected to metal sheets through leads. The lead electrode and the working electrode are provided in the cavity, and the two metal sheets are located between the lead electrode and the working electrode. An insulating plate is provided between the two metal sheets, and the cavity is filled with electrolyte.

4. The oxygen-free device for SF6 mixed gas detector according to claim 1, characterized in that: An electric telescopic rod is provided on the top of the first pipe, the telescopic end of the electric telescopic rod is fixedly connected to the piston, and the electric telescopic rod drives the piston to move up and down along the inner wall of the first pipe.

5. The oxygen-free device for SF6 mixed gas detector according to claim 4, characterized in that: A temperature sensor is provided on the top of the constant temperature box.

6. The oxygen-free device for SF6 mixed gas detector according to claim 5, characterized in that: It also includes a control system, which is electrically connected to the temperature sensor and the electric telescopic rod.

7. The oxygen-free device for SF6 mixed gas detector according to claim 2, characterized in that: The side wall of the sealing shell protrudes outward and is provided with a second air inlet, the second air inlet is provided with a hydrophobic membrane, the sealing shell is fixed to the first pipe with threads, and a rubber pad is provided between the sealing shell and the outer wall of the first pipe.

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