Gas purity transmitter

Abstract

The utility model relates to a gas purity transmitter which comprises a bottom shell and an upper cover, the upper cover is connected with the upper end of the bottom shell, the bottom shell is provided with a containing cavity, an installation sleeve is arranged in the containing cavity, the installation sleeve is made of heat preservation materials, the installation sleeve is provided with an installation hole, and a thermal conductivity sensor structure is inserted in the installation hole. A fixing structure used for fixing the circuit board is arranged on the inner circumferential wall of the bottom shell, and the circuit board is located above the mounting sleeve; an air inlet and an air outlet are formed in the side wall of the bottom shell. A special circuit board mounting structure is designed in the bottom shell, the mounting convenience of the circuit board is improved, the shell is designed for protecting the thermal conductivity sensor, and the mounting convenience and the heat preservation effect of the thermal conductivity sensor structure are improved by designing the mounting sleeve made of a heat preservation material, so that the measurement accuracy is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of gas purity detection, in particular to a gas purity transmitter. Background Art

[0002] Hydrogen is often used as a fuel and also as a medium for heat dissipation in generators in power plants. However, since hydrogen is extremely explosive, in order to control the purity of hydrogen in the equipment, it is necessary to configure an online hydrogen purity analyzer to monitor the purity of hydrogen in real time.

[0003] For example, the utility model patent with authorization announcement number CN215179862U (the same applicant as this case) discloses a thermal conductivity type hydrogen purity detection device, which uses a thermal conductivity sensor to detect gas purity, and sets an explosion-proof filter in the gas chamber to diffuse the gas to be tested, and also plays a certain explosion-proof role. For greater safety, a shell needs to be set outside the thermal conductivity sensor as a protective structure. The utility model patent with authorization announcement number CN219474848U discloses an optimized gas guide structure for an industrial wind differential pressure transmitter. The transmitter shell structure mainly includes a bottom shell and an upper cover. The structure is relatively simple, which is not convenient for installing circuit boards and is not suitable for the installation of thermal conductivity sensors. Utility Model Content

[0004] The utility model aims to provide a gas purity transmitter, which is convenient for installing components such as sensors and protecting the sensors through an optimized shell structure design.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] The gas purity transmitter comprises a bottom shell and an upper cover, wherein the upper cover is connected to the upper end of the bottom shell, the bottom shell has an accommodating cavity, a mounting sleeve is arranged in the accommodating cavity, the mounting sleeve is made of a heat-insulating material, the mounting sleeve has a mounting hole, and a thermal conductivity sensor structure is inserted in the mounting hole; a fixing structure for fixing a circuit board is arranged on the inner peripheral wall of the bottom shell, and the circuit board is located above the mounting sleeve; an air inlet and an air outlet are arranged on the side wall of the bottom shell.

[0007] Furthermore, a partition is provided between the circuit board and the mounting sleeve, and a threading hole is provided on the partition.

[0008] Furthermore, the air inlet and the air outlet are both provided with a first quick-tighten joint.

[0009] Furthermore, one end of the first quick-twist connector is used to connect to a hose located in the bottom shell, and the other end is used to connect to a pipe joint, and the pipe joint is used to connect to an air inlet pipe or an air outlet pipe.

[0010] Furthermore, a dust and flame arrester is provided between the first quick-tight connector and the pipe connector.

[0011] Furthermore, the pipe joint adopts a second quick-tight joint.

[0012] Furthermore, one end of the hose away from the first quick-screw joint is connected to the thermal conductivity cell in the thermal conductivity sensor structure through a third quick-screw joint, and the hose is connected to the detection air cavity in the thermal conductivity cell.

[0013] Furthermore, the thermal conductivity sensor structure includes a thermal conductivity sensor and a thermal conductivity cell. The thermal conductivity sensor is located in the thermal conductivity cell. Both the thermal conductivity sensor and the thermal conductivity cell are electrically connected to the circuit board. The thermal conductivity cell is provided with a heating element and a temperature sensor.

[0014] Furthermore, an over-temperature protection switch is also provided on the thermal conductivity cell, and the over-temperature protection switch is electrically connected to the circuit board.

[0015] Furthermore, the fixing structure includes more than two protrusions, each of which is provided with a fixing hole, and the outer periphery of the mounting sleeve is provided with a making way groove for the protrusions.

[0016] Beneficial effects of the utility model:

[0017] (1) The utility model gas purity transmitter is designed with a special circuit board installation structure in the bottom shell to improve the convenience of circuit board installation. The transmitter outer shell is composed of the bottom shell and the upper cover to protect the thermal conductivity sensor structure therein, and a heat-insulating installation sleeve is provided in the bottom shell. On the one hand, the thermal conductivity sensor can be directly placed therein, which is convenient for installation, and on the other hand, the heat-insulating effect is improved, thereby improving the measurement accuracy of the thermal conductivity sensor.

[0018] (2) A partition is provided between the circuit board and the mounting sleeve, which is made of fire-retardant material, can play an isolation role and can also further improve the thermal insulation effect.

[0019] (3) A dust and flame arrester is installed at the corresponding position of the joint to prevent debris from entering and damaging the sensor. It also has an explosion-proof effect. It is easy and quick to install and maintain and occupies little space.

[0020] (4) The sampled gas enters the thermal conductivity sensor directly without passing through the transmitter housing, thereby reducing the risk of gas leakage and improving safety and measurement accuracy.

[0021] (5) The thermal conductivity pool is equipped with a temperature control switch to prevent overheating caused by temperature control failure and improve safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a three-dimensional diagram of the gas purity transmitter of the utility model;

[0023] Figure 2 This is the first exploded schematic diagram of the partial structure of the gas purity transmitter of the utility model;

[0024] Figure 3 This is the second exploded schematic diagram of the partial structure of the gas purity transmitter of the utility model.

[0025] 1. Explosion-proof compression screw; 2. Rubber plug; 3. Upper cover; 4. Bottom shell; 5. Nut; 6. Gas line connector; 7. Dust and flame arrester; 8. Pipe connector; 9. Ring groove; 10. Fixing hole; 11. Circuit board; 12. Partition; 13. Thermal conductivity sensor structure; 131. Thermal conductivity cell; 1310. Heating rod socket; 132. Thermal conductivity sensor; 133. Over-temperature protection switch; 14. Mounting sleeve; 141. Mounting hole; 142. Give way groove. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the utility model.

[0027] Embodiments of the present utility model:

[0028] like Figure 1-Figure 3 As shown, the gas purity transmitter includes a bottom shell 4 and an upper cover 3. The upper cover 3 is threadedly connected to the upper end of the bottom shell 4 to form the main structure of the transmitter housing, and the interior is used to place a thermal conductivity sensor structure 13, a circuit board 11, etc. The bottom shell 4 and the upper cover 3 are both cast from aluminum alloy. The bottom shell 4 has a accommodating cavity, in which a mounting sleeve 14 is provided. The mounting sleeve 14 is made of a heat-insulating material, such as heat-insulating cotton, which plays a role in heat preservation and shock absorption. The mounting sleeve 14 has a mounting hole 141, and a thermal conductivity sensor structure 13 is inserted into the mounting hole 141. The mounting hole 141 is a circular hole structure as a whole, and its inner wall structure is adapted to the shape of the thermal conductivity sensor structure (using contour processing), so that the wrapping is good, and the thermal conductivity sensor structure 13 can be directly placed without being fixed with screws.

[0029] An annular groove 9 is provided at the upper end of the bottom shell 4 for accommodating an annular gasket to seal with the upper cover 3 .

[0030] The inner wall of the bottom shell 4 is provided with a fixing structure for fixing the circuit board 11, and the circuit board 11 is located above the mounting sleeve 14; the fixing structure includes more than two protrusions, and the protrusions are provided with fixing holes 10, and four fixing holes 10 are shown in the figure, and the circuit board 11 is fixed by screws. The outer periphery of the mounting sleeve 14 is provided with a clearance groove 142 for the several protrusions to make way, and the clearance groove 142 is a vertical long groove.

[0031] A partition 12 is also provided between the circuit board 11 and the mounting sleeve 14. The partition 12 is provided with a threading hole for passing cables, such as the cable connected between the circuit board 11 and the thermal conductivity sensor structure 13, the signal line responsible for collecting signals, and the heating wire. The partition 12 is located on the lower side of the circuit board 11, and plays an isolating role, further improving the heat preservation effect of the thermal conductivity pool 131, and also reducing the impact of heat on the circuit board 11. The partition 12 is directly pressed on the upper side of the thermal conductivity sensor, and also plays a role in fixing the relative position.

[0032] The thermal conductivity sensor structure 13 includes a thermal conductivity sensor 132 and a thermal conductivity pool 131. The thermal conductivity sensor 132 is located in the thermal conductivity pool 131. The thermal conductivity sensor 132 and the thermal conductivity pool 131 are electrically connected to the circuit board 11. The thermal conductivity pool 131 is provided with a heating element and a temperature sensor. The heating element is a heating rod, and the thermal conductivity pool 131 is provided with a heating rod jack 1310 and a temperature sensor mounting hole 141. The heating rod is an electric heating rod. In other embodiments, an electric heating wire or the like can also be used. The heating rod is used to heat the thermal conductivity pool 131 to a set temperature. The set temperature is higher than the highest temperature of the external environment where the gas purity transmitter is located (for example, the highest temperature of the ambient temperature change is 30°C and the lowest temperature is minus 10°C, then the set temperature is greater than 30°C and can be set to 35°C), so that the thermal conductivity sensor performs gas purity detection at a relatively constant temperature to avoid the influence of external environmental temperature fluctuations, thereby improving the detection accuracy. The temperature sensor is used to monitor the temperature of the thermal conductivity pool 131 in real time and feed back the signal to the circuit board 11 to determine whether to continue heating or stop heating.

[0033] Furthermore, an over-temperature protection switch 133 is also provided on the thermal conductivity pool 131, and the over-temperature protection switch 133 is electrically connected to the circuit board 11. The over-temperature protection switch 133 is a temperature control switch, which plays a protective role. For example, when the temperature sensor fails, the temperature control switch can prevent the thermal conductivity pool 131 from being heated to an excessively high temperature. When the temperature of the thermal conductivity pool 131 exceeds the set safe temperature value, the temperature control switch can cut off the heating path and stop heating. In terms of temperature control, it is similar to the prior patent, such as the patent with authorization announcement number CN215179862U cited in the background technology.

[0034] An air inlet and an air outlet are provided on one side of the side wall of the bottom shell 4. The air inlet and the air outlet are both provided with a first quick-tightening joint, including a nut 5 and an air path joint 6. One end of the first quick-tightening joint is used to connect a hose located in the bottom shell 4, and the other end is used to connect a pipe joint 8. The pipe joint 8 is used to connect an air inlet pipe or an air outlet pipe. The air inlet pipe is used to input the gas to be measured, and the air outlet pipe is used to exhaust. The end of the hose away from the first quick-tightening joint is connected to the thermal conductivity pool 131 through a third quick-tightening joint (the third quick-tightening joint and the hose are not shown, and the prior patent CN215179862U can be referred to). The hose is connected to the detection air cavity in the thermal conductivity pool 131, and the detection air cavity is located at the lower side of the thermal conductivity sensor. There are two hoses arranged in parallel, one for inlet and one for outlet. The gas to be measured enters from the air inlet pipe, then flows to the detection air cavity through one of the hoses, is detected by the thermal conductivity sensor, and then flows to the air outlet through the other hose. The hose passes through the notch opened at the bottom end of the mounting sleeve 14.

[0035] One end of the first quick-twist joint connected to the pipe joint 8 is an internal thread. The pipe joint 8 preferably adopts the second quick-twist joint, which can be quickly connected; other mature connectors such as pagoda joints, self-locking sealing joints, etc. can also be used.

[0036] The first quick-tightening connector, the second quick-tightening connector and the third quick-tightening connector are mature products in the prior art.

[0037] A dustproof flame arrester 7 is provided between the first quick-tightening joint and the pipe joint 8. The dustproof flame arrester 7 can prevent debris from entering and damaging the sensor, and also has an explosion-proof effect. It is convenient and quick to install and maintain, and occupies a small space. The dustproof flame arrester 7 is made of sintered metal and has a microporous structure. It allows gas to pass through and can play a role in dustproof and fireproof. The principle of this component is the existing technology. Figure 2 The one shown in the figure is made into a stepped shaft shape, which cooperates with the inner cavity of the matching joint and is installed in the inner cavity of the corresponding joint.

[0038] A threaded opening is provided on the other side of the bottom shell 4 for installing a cable, and the cable is electrically connected to the circuit board 11. The cable is fixed after passing through the threaded opening using an explosion-proof clamping screw 1 and a rubber plug 2. The explosion-proof clamping screw 1 can also be replaced with an explosion-proof adapter and used in conjunction with an explosion-proof cable pipe to achieve explosion-proof cable lines.

Claims

1. Gas purity transmitter, characterized by: It includes a bottom shell and an upper cover, the upper cover is connected to the upper end of the bottom shell, the bottom shell has a accommodating cavity, a mounting sleeve is arranged in the accommodating cavity, the mounting sleeve is made of a heat-insulating material, the mounting sleeve has a mounting hole, and a thermal conductivity sensor structure is inserted in the mounting hole; a fixing structure for fixing a circuit board is arranged on the inner peripheral wall of the bottom shell, and the circuit board is located above the mounting sleeve; an air inlet and an air outlet are arranged on the side wall of the bottom shell.

2. The gas purity transmitter according to claim 1, characterized in that: A partition is also arranged between the circuit board and the installation sleeve, and a threading hole is arranged on the partition.

3. The gas purity transmitter according to claim 1, characterized in that: The air inlet and the air outlet are both provided with a first quick-tightening joint.

4. The gas purity transmitter according to claim 3, characterized in that: One end of the first quick-twist connector is used to connect to a hose located in the bottom shell, and the other end is used to connect to a pipe connector, and the pipe connector is used to connect to an air inlet pipe or an air outlet pipe.

5. The gas purity transmitter according to claim 4, characterized in that: A dust and flame arrester is provided between the first quick-tightening joint and the pipe joint.

6. The gas purity transmitter according to claim 4, characterized in that: The pipe joint adopts a second quick-tightening joint.

7. The gas purity transmitter according to claim 4, characterized in that: One end of the hose away from the first quick-screw joint is connected to the thermal conductivity cell in the thermal conductivity sensor structure through a third quick-screw joint, and the hose is connected to the detection air cavity in the thermal conductivity cell.

8. The gas purity transmitter according to claim 1, characterized in that: The thermal conductivity sensor structure comprises a thermal conductivity sensor and a thermal conductivity cell. The thermal conductivity sensor is located in the thermal conductivity cell. Both the thermal conductivity sensor and the thermal conductivity cell are electrically connected to the circuit board. A heating element and a temperature sensor are arranged on the thermal conductivity cell.

9. The gas purity transmitter according to claim 8, characterized in that: An over-temperature protection switch is also provided on the thermal conductivity pool, and the over-temperature protection switch is electrically connected to the circuit board.

10. The gas purity transmitter according to claim 1, characterized in that: The fixing structure comprises more than two protrusions, each of which is provided with a fixing hole, and the outer periphery of the mounting sleeve is provided with a making way groove for making way for the protrusions.

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