Special thermal conductivity detector for mining intrinsic safety type monitoring master station

Abstract

The utility model relates to the technical field of thermal conductivity detectors, in particular to a thermal conductivity detector special for a mining intrinsic safety type monitoring master station, which comprises a TCD box, a TCD detector is arranged in the TCD box, the TCD detector is electrically connected with a detection circuit, a base is arranged at the bottom of the inner side face of the TCD box, a heating wire is arranged in the middle of the base, a platinum resistor is arranged on the heating wire, and a resistor is arranged on the platinum resistor. And heat preservation cotton is filled between the TCD detector and the TCD box. In the working process, the TCD can work without heating, the TCD is a concentration type detector which responds according to different thermal conductivity coefficients of a detected component and a reference gas, the temperature of a platinum resistor is stabilized at a certain value, pure carrier gas is introduced into the TCD, and the same carrier gas has the same thermal conductivity, so that the temperature of a platinum resistor is stabilized at a certain value. The method is not influenced by the external environment, and the stability and accuracy of the detection result are improved.

Description

Technical Field

[0001] The utility model relates to a special thermal conductivity detector, in particular to a special thermal conductivity detector for a mine intrinsically safe monitoring main station, belonging to the technical field of thermal conductivity detectors. Background Art

[0002] Thermal conductivity detector is the most commonly used detector in gas chromatography. In order to ensure the accuracy of detection, it must be ensured that the thermal conductivity detector is not affected by the external ambient temperature. Traditional thermal conductivity detectors have insulation caps to reduce the impact of the external ambient temperature on the detection cell.

[0003] However, in actual application, it is found that changes in external ambient temperature will still have more or less impact on the detection cell, so it is necessary to create a relatively constant temperature environment. Changes in the external temperature of the existing thermal conductivity detector will be transmitted to the detection cell by conduction, thereby affecting the stability and accuracy of the detection results.

[0004] Therefore, there is an urgent need to improve the thermal conductivity detector to solve the above-mentioned problems. Utility Model Content

[0005] The purpose of the utility model is to provide a thermal conductivity detector dedicated to a mine intrinsically safe monitoring main station. During operation, the TCD detector can work without heating. The TCD detector is a concentration-type detector that responds to the different thermal conductivities of the measured component and the reference gas. The temperature of the platinum resistor is stabilized at a certain value. Since pure carrier gas is introduced into the TCD detector, the same carrier gas has the same thermal conductivity and is not affected by the external environment, thereby improving the stability and accuracy of the detection result.

[0006] In order to achieve the above-mentioned purpose, the main technical solutions adopted by the utility model include:

[0007] A thermal conductivity detector dedicated to a mine intrinsically safe monitoring main station comprises a TCD box, a TCD detector is fixedly arranged inside the TCD box, a detection circuit is electrically connected to the TCD detector, air outlets are fixedly arranged on both sides of the TCD box, an air inlet is fixedly arranged on the bottom of the TCD box, and the air outlet or the air inlet is connected to the TCD detector through a conduit;

[0008] A base is fixedly provided at the bottom of the inner side of the TCD box, a heating wire is fixedly provided in the middle of the base, a platinum resistor is fixedly provided on the heating wire, the heating wire is used to heat the air inlet, and thermal insulation cotton is filled between the TCD detector and the TCD box.

[0009] Preferably, a heat conductor is fixedly provided on the upper side of the base, a TCD box cover is fixedly provided between the upper end of the heat conductor and the thermal insulation cotton, the TCD box cover and the heat conductor are used to seal the TCD detector, an air bath room is filled between the TCD box cover and the heat conductor, an asbestos heat-resistant pad is fixedly provided between the base and the bottom of the TCD box, and the asbestos heat-resistant pad is used to isolate the base from the TCD box.

[0010] Preferably, one end of the air inlet sequentially passes through the TCD box and the base and is fixed on the base by screws;

[0011] A pressing sheet is fixedly arranged between the air inlet and the base.

[0012] Preferably, the other end of the air inlet is fixedly arranged on the bottom side of the TCD box by a fastening nut;

[0013] A fixed connection block is fixedly arranged at the bottom of the TCD box, and the fixed connection block is fixedly connected to the outer side surface of the TCD box by welding.

[0014] Preferably, the upper end of the TCD box is connected to a shell cover, the shell cover is snap-fitted to the TCD box, and a cover fixing bolt is fixedly provided on the circumference of the shell cover, the cover fixing bolt passes through the shell cover and is fixedly connected to the TCD box.

[0015] Preferably, the detection circuit includes a chip U13, a chip U5 and an integrated operational amplifier U4 arranged in series, a transistor Q1 is electrically connected to pin 1 of the integrated operational amplifier U4, and the transistor Q1IRF4905STRLPBF is electrically connected, a TCD power amplifier T1 is arranged in parallel between the integrated operational amplifier U4 and the transistor Q1, a chip U9 is electrically connected to the transistor Q1, and a chip U14 is connected to the chip U9 through a diode D3, and the model of the chip U14 is: SN74LVC1G125DBVR;

[0016] A voltage comparator U3 is electrically connected between the transistor Q1 and the TCD power amplifier T1 , and the model of the voltage comparator U3 is AP331AWRG-7.

[0017] The utility model has at least the following beneficial effects:

[0018] 1. During operation, the TCD detector can work without heating. The TCD detector is a concentration-type detector that responds to the difference in thermal conductivity between the measured component and the reference gas. The temperature of the platinum resistor is stable at a certain value. Since the TCD detector is fed with pure carrier gas, the same carrier gas has the same thermal conductivity and is not affected by the external environment, which improves the stability and accuracy of the test results.

[0019] 2. The carrier gas carries the component gas to the TCD detector inside the TCD box. Since the thermal conductivity of the binary mixed gas of the carrier gas and the component to be measured is different from that of the pure carrier gas, the heat dissipation in the TCD box changes, causing a difference between the reference cell and the platinum resistor in the TCD box hole. The bridge loses balance, and the detection circuit outputs a voltage signal. The more significant the changes in temperature and resistance value, the stronger the voltage signal. At this time, the output voltage signal is proportional to the concentration of the sample. In order to better protect the thermistor, helium is used as the carrier gas. When the sample enters the TCD box, the voltage of the two platinum resistors in the sample channel is constant, and the current will decrease accordingly, thereby reducing the heating of the heating wire and achieving the purpose of protecting the platinum resistor. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0021] Figure 1 It is a structural diagram of the utility model;

[0022] Figure 2 This is a detection circuit diagram of the utility model.

[0023] In the figure, 1-housing cover, 2-TCD box upper cover, 3-TCD box, 4-TCD detector, 5-heat conductor, 6-base, 7-screw, 8-pressing sheet, 9-platinum resistor, 10-heating wire, 11-fastening nut, 12-asbestos thermal pad, 13-air bath, 16-detection circuit, 17-insulation cotton, 18-air outlet, 19-air inlet, 20-fixed connecting block, 21-cover fixing bolt. DETAILED DESCRIPTION

[0024] The following will describe the implementation methods of the present application in detail with the help of accompanying drawings and examples, so that the implementation process of how the present application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0025] like Figure 1-Figure 2As shown, the thermal conductivity detector dedicated to the mine intrinsically safe monitoring master station provided in this embodiment includes a TCD box 3, a TCD detector 4 is fixedly arranged inside the TCD box 3, a detection circuit 16 is electrically connected to the TCD detector 4, air outlets 18 are fixedly arranged on both sides of the TCD box 3, an air inlet 19 is fixedly arranged at the bottom of the TCD box 3, and the air outlet 18 or the air inlet 19 is connected to the TCD detector 4 through a conduit, a base 6 is fixedly arranged at the bottom of the inner side of the TCD box 3, a heating wire 10 is fixedly arranged in the middle of the base 6, a platinum resistor 9 is fixedly arranged on the heating wire 10, and the heating wire 10 is used to heat the air inlet 19, and a thermal insulation cotton 17 is filled between the TCD detector 4 and the TCD box 3;

[0026] During operation, the TCD detector 4 can work without heating. The TCD detector 4 is a concentration-type detector that responds to the different thermal conductivity coefficients of the measured component and the reference gas. The platinum resistor 9 has the characteristic that the resistance changes with temperature. When a constant direct current passes through the TCD detector 4, the heating wire 10 is heated. Due to the heat conduction of the carrier gas, part of the heat of the platinum resistor 9 is taken away by the carrier gas, and part is transferred to the TCD box 3. When the heat generated by the platinum resistor 9 reaches a balance with the heat dissipated, the temperature of the platinum resistor 9 is stabilized at a certain value. At this time, the resistance value of the platinum resistor 9 is also stabilized at a certain value. Since the TCD detector 4 is fed with pure carrier gas, the same carrier gas has the same thermal conductivity and is not affected by the external environment, thereby improving the stability and accuracy of the detection result.

[0027] Further, such as Figure 1 As shown, a heat conductor 5 is fixedly arranged on the upper side of the base 6, a TCD box upper cover 2 is fixedly arranged between the upper end of the heat conductor 5 and the heat insulation cotton 17, the TCD box upper cover 2 and the heat conductor 5 are used to seal the TCD detector 4, an air bath 13 is filled between the TCD box upper cover 2 and the heat conductor 5, and an asbestos heat-resistant pad 12 is fixedly arranged at the bottom of the base 6 and the TCD box 3. The asbestos heat-resistant pad 12 is used to isolate the base 6 from the TCD box 3, which helps to prevent heat loss and improve the sealing of the device;

[0028] One end of the air inlet 19 passes through the TCD box 3 and the base 6 in sequence and is fixed on the base 6 by a screw 7, and a pressing sheet 8 is fixedly arranged between the air inlet 19 and the base 6, and the other end of the air inlet 19 is fixedly arranged on the bottom side of the TCD box 3 by a fastening nut 11, which improves the stability of the air inlet 19 on the one hand, and helps to reduce heat loss and improve the sealing of the device on the other hand;

[0029] A fixed connection block 20 is fixedly arranged at the bottom of the TCD box 3, and the fixed connection block 20 is fixedly connected to the outer side of the TCD box 3 by welding. The fixed connection block 20 on the TCD box 3 is convenient for fixing the TCD box 3, thereby improving the overall stability of the TCD box 3;

[0030] Furthermore, Figure 1 As shown, the upper end of the TCD box 3 is connected to the outer shell cover 1, and the outer shell cover 1 is clamped on the TCD box 3. The outer shell cover 1 is fixedly provided with a cover fixing bolt 21 on the peripheral side. The cover fixing bolt 21 penetrates the outer shell cover 1 and is fixedly connected to the TCD box 3. The interior of the TCD box 3 is filled with thermal insulation cotton 17, which plays a certain thermal insulation role, and then the TCD box 3 is sealed by the outer shell cover 1 to improve the overall sealing of the TCD box 3.

[0031] Further, if Figure 2 As shown, the detection circuit 16 includes a chip U13, a chip U5 and an integrated operational amplifier U4 which are arranged in series. A transistor Q1 is electrically connected to pin 1 of the integrated operational amplifier U4. The transistor Q1IRF4905STRLPBF is electrically connected. A TCD power amplifier T1 is arranged in parallel between the integrated operational amplifier U4 and the transistor Q1. A chip U9 is electrically connected to the transistor Q1. A chip U14 is connected to the chip U9 through a diode D3. The model of the chip U14 is: SN74LVC1G125DBVR. A voltage comparator U3 is electrically connected between the transistor Q1 and the TCD power amplifier T1. The model of the voltage comparator U3 is: AP331AWRG-7. When a sample enters the detector through the air inlet 19, the pure carrier gas flows through the reference cell, and the carrier gas carries the component gas TCD box 3. The internal TCD detector 4 has different thermal conductivity of the binary mixed gas of the carrier gas and the component to be measured and the thermal conductivity of the pure carrier gas, so the heat dissipation in the TCD box 3 changes, resulting in a difference between the reference cell and the platinum resistor 9 in the hole of the TCD box 3, the bridge loses balance, the detection circuit 16 has a voltage signal output, and the recorder draws the chromatographic peak of the corresponding component. The greater the concentration of the component to be measured in the carrier gas, the more significant the change in the thermal conductivity of the gas in the TCD box 3, the more significant the change in temperature and resistance value, and the stronger the voltage signal. At this time, the output voltage signal is proportional to the concentration of the sample, so as to better protect the thermistor. Helium is used as the carrier gas. When the sample enters the TCD box 3, the voltage of the two platinum resistors 9 in the sample channel is constant, and the current will be reduced accordingly, thereby reducing the heating of the heating wire 10 and achieving the purpose of protecting the platinum resistor 9.

[0032] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criteria for distinction. For example, "including" mentioned throughout the specification and claims is an open term, so it should be interpreted as "including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve technical problems within a certain error range and basically achieve technical effects.

[0033] It should be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such product or system. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the product or system including the elements.

[0034] The above description shows and describes several preferred embodiments of the utility model, but as mentioned above, it should be understood that the utility model is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the utility model concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not deviate from the spirit and scope of the utility model, and should be within the scope of protection of the claims attached to the utility model.

Claims

1. A thermal conductivity detector dedicated to a mine intrinsically safe monitoring master station, comprising a TCD box (3), characterized in that: A TCD detector (4) is fixedly arranged inside the TCD box (3), and a detection circuit (16) is electrically connected to the TCD detector (4). Air outlets (18) are fixedly arranged on both sides of the TCD box (3), and an air inlet (19) is fixedly arranged on the bottom of the TCD box (3), and the air outlet (18) or the air inlet (19) is connected to the TCD detector (4) through a conduit; A base (6) is fixedly arranged at the bottom of the inner side of the TCD box (3), a heating wire (10) is fixedly arranged in the middle of the base (6), a platinum resistor (9) is fixedly arranged on the heating wire (10), and the heating wire (10) is used to heat the air inlet (19). Insulation cotton (17) is filled between the TCD detector (4) and the TCD box (3).

2. The thermal conductivity detector dedicated to the mine intrinsically safe monitoring master station according to claim 1 is characterized by: A heat conductor (5) is fixedly arranged on the upper side of the base (6); a TCD box upper cover (2) is fixedly arranged between the upper end of the heat conductor (5) and the heat insulation cotton (17); the TCD box upper cover (2) and the heat conductor (5) are used to seal the TCD detector (4); An air bath (13) is filled between the TCD box upper cover (2) and the heat conductor (5).

3. The thermal conductivity detector dedicated to the mine intrinsically safe monitoring master station according to claim 1 is characterized by: An asbestos heat-resistant pad (12) is fixedly provided at the bottom of the base (6) and the TCD box (3), and the asbestos heat-resistant pad (12) is used to isolate the base (6) from the TCD box (3).

4. The thermal conductivity detector dedicated to the mine intrinsically safe monitoring master station according to claim 1 is characterized by: One end of the air inlet (19) passes through the TCD box (3) and the base (6) in sequence and is fixed on the base (6) by means of screws (7); A pressing sheet (8) is fixedly arranged between the air inlet (19) and the base (6).

5. The thermal conductivity detector dedicated to the mine intrinsically safe monitoring master station according to claim 1 is characterized by: The other end of the air inlet (19) is fixedly arranged on the bottom side of the TCD box (3) through a fastening nut (11); A fixed connection block (20) is fixedly arranged at the bottom of the TCD box (3), and the fixed connection block (20) is fixedly connected to the outer side surface of the TCD box (3) by welding.

6. The thermal conductivity detector dedicated to the mine intrinsically safe monitoring master station according to claim 1 is characterized by: The upper end of the TCD box (3) is connected to an outer shell cover (1), the outer shell cover (1) is snap-fitted onto the TCD box (3), and a cover fixing bolt (21) is fixedly provided on the circumference of the outer shell cover (1), the cover fixing bolt (21) passes through the outer shell cover (1) and is fixedly connected to the TCD box (3).

7. The thermal conductivity detector dedicated to the mine intrinsically safe monitoring master station according to claim 1 is characterized by: The detection circuit (16) comprises a chip U13, a chip U5 and an integrated operational amplifier U4 arranged in series, wherein pin 1 of the integrated operational amplifier U4 is electrically connected to a transistor Q1, wherein the transistor Q1IRF4905STRLPBF, and a TCD power amplifier T1 is arranged in parallel between the integrated operational amplifier U4 and the transistor Q1.

8. The thermal conductivity detector dedicated to the mine intrinsically safe monitoring master station according to claim 7 is characterized by: The transistor Q1 is electrically connected to a chip U9, and the chip U9 is connected to a chip U14 via a diode D3. The model of the chip U14 is: SN74LVC1G125DBVR; A voltage comparator U3 is electrically connected between the transistor Q1 and the TCD power amplifier T1 , and the model of the voltage comparator U3 is AP331AWRG-7.

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