Air channel structure of sensor

Abstract

The invention relates to the technical field of design of air channel structures of sensors, in particular to an air channel structure of a sensor, which comprises an air channel in the sensor, the air channel comprises a plurality of air channel parts and a communication corner, and the communication corner is communicated with two adjacent air channel parts with an included angle; the difference of the cross sectional area of each air channel part does not exceed + / -10%; and an arc-shaped moving channel is arranged in the communicating corner. The two adjacent air channel parts with the included angle are communicated through the communication corner, and the arc-shaped moving channel is adopted in the communication corner, so that the two adjacent air channel parts with the included angle can be in smooth transition, and then the possibility that gas vortexes are generated at the included angle is reduced. And the difference of the cross sectional areas of all the air channel parts does not exceed + / -10%, so that the flowing speed change of the air in the air channel parts is small, the updating efficiency of the air in the air channels can be improved, and the same sensor product has higher performance consistency on different instruments.

Description

Technical Field

[0001] The invention relates to the technical field of air channel structure design of a sensor, and in particular to an air channel structure of a sensor. Background Art

[0002] The response speed and response accuracy of gas detection sensors are the main and important performance indicators. The renewal efficiency of the gas inside the sensor is the main factor affecting the above indicators. Since the same type of PID sensors are mostly miniature and compact in design, they do not include the airway structure inside the sensor or the problems caused by the airway structure are not considered because the airway is too short. From the perspective of product use, this actually leaves the problem to the design of the instrument and equipment, increases the difficulty of sensor use or integration, and will cause the same sensor product to have inconsistent performance on different instruments.

[0003] The existing airway structure does not take into account the impact of the airway structure design on the gas detection sensor, which is prone to produce eddy currents, retention, pollutant retention or dead corners, etc., which slows down the airflow update and leads to inconsistent performance of the same sensor product on different instruments. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the existing airway structure in the prior art that the existing airway structure does not take into account the impact of the airway structure design on the gas detection sensor, which is prone to produce eddy currents, retention, pollutant retention or dead corners, etc., which makes the airflow update slow, and thus leads to inconsistent performance of the same sensor product on different instruments, and to provide an air channel structure for a sensor.

[0005] In a first aspect, the present invention provides an air channel structure of a sensor, including an air channel in the sensor, the air channel including a plurality of air channel parts and a connecting corner, the connecting corner connecting two adjacent air channel parts having an angle;

[0006] The cross-sectional area of ​​each airway segment did not vary by more than ±10%;

[0007] An arc-shaped passage is provided inside the connecting corner.

[0008] The sampled gas can enter the airway in the sensor through the airway inlet. Two adjacent airway parts with an angle are connected through a connecting corner, and an arc-shaped channel is used inside the connecting corner, so that the two adjacent airway parts with an angle can transition smoothly, thereby reducing the possibility of gas vortexes at the angle; and the cross-sectional area difference of each airway part does not exceed ±10%, thereby ensuring that the speed of the gas flowing in the airway part changes little, thereby improving the renewal efficiency of the gas in the airway, so that the same sensor product has higher performance consistency on different instruments.

[0009] Preferably, all the channel cross-sectional areas of each airway portion are the same, which can ensure that the speed of gas flowing in the airway portion is basically consistent, further improving the renewal efficiency of the gas in the airway.

[0010] Preferably, an arc-shaped passage is used inside the connecting corner, so that two adjacent airway parts with an angle can have a better smooth transition, further reducing the possibility of gas vortex generation at the angle.

[0011] Preferably, when there is a corner between two adjacent airway parts and the angle is greater than or equal to 30°, a guide fin is provided on the inner wall of the connecting corner of the two adjacent airway parts, and the direction of the guide fin is adapted to the central axis of the connecting corner, so that the gas is smoother when turning sharply, and the gas renewal efficiency is improved.

[0012] Preferably, all channel cross sections of each airway portion are the same, that is, all channel cross sections of each airway portion are of the same shape and size, which can ensure that the speed of gas flowing in the airway portion is basically consistent, improve the smoothness of gas flow, and further improve the renewal efficiency of gas in the airway.

[0013] Preferably, the centers of all channel cross sections of the airway portion are located on the same straight line, and the centers of all channel cross sections of all airway portions are located on the same plane, which can ensure that the speed of gas flowing in the airway portion is basically consistent, and can improve the smoothness of gas flow, and further improve the renewal efficiency of gas in the airway.

[0014] Preferably, all channel cross-sections of all airway parts are the same, which can ensure that the speed of gas flowing in all airway parts is basically consistent, and can improve the smoothness of gas flow, and further improve the renewal efficiency of gas in the airway.

[0015] Preferably, an ionization chamber is arranged in one of the airway parts, the ionization chamber has an ionization cavity, the ionization cavity is used to ionize the gas, the ionization cavity has an air inlet and an air outlet, and the air inlet and the air outlet are respectively connected to the two ends of the airway part.

[0016] Almost all the gas entering the airway actively enters the ionization cavity of the ionization chamber for ionization, and then leaves, thereby increasing the total ionization amount of the gas in the airway. Compared with the method in which the sampling gas freely diffuses into the ionization chamber for ionization, the present application sets the ionization chamber on the path that the detection gas must pass through, and will not affect the entry and discharge of the detection gas. The ozone ions in the space in the ionization chamber are discharged along with the detection gas, thereby improving the ionization effect; and the introduced detection gas can be basically ionized, thereby making the amount of ionized gas larger in the same time, the positively charged ions obtained by ionization are more, and the electrical signal obtained by ionization is stronger, so that the sensor response sensitivity is high, and the result data is consistent with the actual concentration of the gas being measured, so that the detection result is more accurate.

[0017] Preferably, the cross section of the airway portion used to set the ionization chamber is a rectangular cross section, the four corners of the rectangular cross section have arc chamfers, and the cross section of the remaining airway portion is circular.

[0018] The cross-section of the airway portion used to set up the ionization chamber is a rectangular cross-section, which can better set up the ionization chamber and ensure the sealing performance to avoid air leakage at the location where the ionization chamber is set; the four corners of the rectangular cross-section have arc-shaped guide angles to reduce the generation of eddy currents, retention, pollutant retention or dead corners, etc., and can improve the smoothness of gas flow.

[0019] Preferably, the airway includes three airway parts, which are an inlet airway, a middle airway and an outlet airway, respectively. The inlet airway and the outlet airway are located on the same side of the middle airway, and the ionization chamber is arranged in the middle airway;

[0020] The channel cross-sections of the intake air ducts are the same;

[0021] The channel cross-sections of the intermediate air passages are the same, and one end of the intermediate air passages is connected to one end of the intake air passage via a connecting corner;

[0022] The channel cross-sections of the outlet air passages are the same, and the outlet end of the outlet air passages is connected to the other end of the inlet air passage through a connecting corner;

[0023] The inner wall of the connecting corner is provided with guide fins whose direction matches the central axis of the connecting corner.

[0024] This arrangement makes it relatively simple to arrange the airway in the sensor. The detection gas can quickly enter the ionization chamber in the middle airway from the air inlet airway for detection, and then leave from the air outlet airway. The channel cross-sections of the air inlet airway, the middle airway and the air outlet airway are the same, which can ensure that the gas flow speed in each airway part remains basically unchanged. The air inlet airway and the middle airway, and the middle airway and the air outlet are connected through a connecting corner. A curved channel is used inside the connecting corner, so that the air inlet airway and the middle airway, and the middle airway and the air outlet, which have an included angle, can have a smooth transition. Thereby reducing the possibility of gas eddy currents being generated at the angle; and the inner wall of the connecting corner is provided with guide fins whose direction matches the central axis of the connecting corner, so that even if the cross-section of the intermediate airway is different from that of the inlet airway and the outlet airway, the gas can still be smoother when making a large turn; the above method significantly improves the gas renewal efficiency in the gas channel inside the sensor, avoids the problem of low gas renewal efficiency caused by gas retention inside the sensor and pressure fluctuations caused by gas flow, makes the detection gas smoother, and the detection gas is renewed faster in the airway, so that the performance of the same sensor product on different instruments is basically the same.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The present invention provides an air channel structure of a sensor, including an air channel in the sensor, wherein the air channel includes a plurality of air channel parts and a connecting corner, wherein the connecting corner connects two adjacent air channel parts with an angle, and the two adjacent air channel parts with the angle are connected through the connecting corner, and an arc-shaped channel is used inside the connecting corner, so that the two adjacent air channel parts with the angle can be smoothly transitioned, thereby reducing the possibility of gas vortexes generated at the angle; and the cross-sectional area difference of each air channel part does not exceed ±10%, thereby ensuring that the speed change of the gas flowing in the air channel part is small, thereby improving the renewal efficiency of the gas in the air channel, so that the same sensor product has higher performance consistency on different instruments. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the air channel structure of the sensor of the present invention;

[0028] Figure 2 A simulated comparison diagram of airway flow rates of the air channel structure of the sensor of the present invention and a non-optimized air channel structure;

[0029] Figure 3 is a simulated comparison diagram of airway pressure of the air channel structure of the sensor of the present invention and the air channel structure that is not optimized;

[0030] Figure 4 It is a schematic diagram of the arrangement of the ionization chamber and the air passage structure of the sensor of the present invention in the sensor;

[0031] Figure 5 It is a schematic diagram of the arrangement of the ionization chamber in the air channel structure of the sensor of the present invention.

[0032] Markings in the figure:

[0033] 1. Airway; 11. Air inlet; 12. Intermediate airway; 13. Air outlet; 141. First connecting corner; 142. Second connecting corner; 15. Guide fin; 2. Ionization chamber; 21. Ionization chamber body; 22. Inner needle; 23. Ionization lamp; 3. Sensor. DETAILED DESCRIPTION

[0034] The present invention is further described in detail below in conjunction with specific embodiments. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0035] Unless otherwise specified, in the description of the specific embodiments of the present invention, the terms indicating the orientation or position relationship such as "up", "down", "left", "right", "center", "inside", "outside", etc. are all based on the expression of the orientation or position relationship shown in the drawings, or are the orientation or position relationship when the invented product / equipment / device is usually used. These terms of orientation or position relationship are only for the convenience of describing the scheme of the present invention or simplifying the description in the specific embodiments, so as to facilitate the technicians to quickly understand the scheme, and do not indicate or imply that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific position relationship, and therefore cannot be understood as a limitation on the present invention.

[0036] In addition, if the terms "horizontal", "vertical", "overhanging", "parallel" and the like appear, it does not mean that the corresponding devices / components / elements are required to be absolutely horizontal or vertical or overhanging or parallel, but may be slightly tilted or have deviations. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but may be slightly tilted. Alternatively, it can be simplified to mean that the corresponding devices / components / elements are set in directions such as "horizontal", "vertical", "overhanging", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably an error / deviation within ±8%, more preferably an error / deviation within ±6%, more preferably an error / deviation within ±5%, and more preferably an error / deviation within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its role in the scheme of the present invention.

[0037] In addition, the expressions “first”, “second”, “third”, etc., which appear in the terms, are merely used to distinguish the description of the same or similar components and should not be understood as emphasizing or implying the relative importance of specific components.

[0038] In addition, in the description of the embodiments of the present invention, "several", "plurality" and "a number" represent at least 2. It can be any number such as 2, 3, 4, 5, 6, 7, 8, 9, and even more than 9.

[0039] In addition, in the description of the technical solution of the present invention, unless otherwise clearly specified / defined / restricted, the terms "set", "installed", "connected", "connected", "provided with", "laid" and "arranged" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection, and can be welding, riveting, bolting, threaded connection and other commonly used connection means in the field.

[0040] Example 1

[0041] like Figure 1 and Figure 4As shown, an air channel structure of a sensor 3 includes an air channel 1 in the sensor 3, the air channel 1 includes a plurality of air channel parts and a connecting corner, and the connecting corner connects two adjacent air channel parts having an angle;

[0042] The cross-sectional area of ​​each airway segment did not vary by more than ±10%;

[0043] An arc-shaped passage is provided inside the connecting corner.

[0044] The sampled gas can enter the airway 1 in the sensor 3 from the airway 1 inlet end. Two adjacent airway parts with an angle are connected through a connecting corner, and an arc-shaped channel is used inside the connecting corner, so that the two adjacent airway parts with an angle can transition smoothly, thereby reducing the possibility of gas vortexes at the angle; and the cross-sectional area difference of the same airway part does not exceed ±10%, thereby ensuring that the speed of the gas flowing in the airway part changes little, thereby improving the renewal efficiency of the gas in the airway 1, so that the same sensor 3 product has higher performance consistency on different instruments.

[0045] In this solution, by designing the cross-section of each airway portion, the flow rate of each airway portion can be made smooth; and by designing the connecting angle between two adjacent airway portions with an angle, the possibility of gas vortex generation at the angle can be reduced, thereby improving the renewal efficiency of the gas in the airway 1.

[0046] In some embodiments, all channel cross-sectional areas of each airway portion are the same, which can ensure that the speed of gas flowing in the airway portion is basically the same, and further improve the gas renewal efficiency in the airway 1. Further, all channel cross-sectional areas of each airway portion are the same, which can ensure that the speed of gas flowing in the airway portion is basically the same, and can improve the smoothness of gas flow, and further improve the gas renewal efficiency in the airway 1. Further, the centers of all channel cross-sectional areas of the airway portion are located on the same straight line, that is, all channel cross-sectional areas of the airway portion are basically located on the same straight line, which can ensure that the speed of gas flowing in the airway portion is basically the same, and can improve the smoothness of gas flow, and further improve the gas renewal efficiency in the airway 1. Further, all channel cross-sectional areas of all airway portions are the same, and the centers of all channel cross-sectional areas of all airway portions are located on the same plane, so that the flow rates of all channel cross-sectional areas of all airway portions are basically the same, and can improve the smoothness of gas flow, and further improve the gas renewal efficiency in the airway 1.

[0047] In some embodiments, the interior of the connecting corner adopts an arc-shaped channel, such as Figure 1As shown, the arc-shaped channel adapts to the arc-shaped formed by the angle, so that the two adjacent airway parts with the angle can have a better smooth transition, further reducing the possibility of gas vortexes at the angle. Furthermore, when there is a corner between two adjacent airway parts and the angle is greater than or equal to 30°, a guide fin 15 is set on the inner wall of the connecting corner of the two adjacent airway parts, and the direction of the guide fin 15 is adapted to the central axis of the connecting corner, so that the gas is smoother when it turns sharply, and the gas renewal efficiency is improved. And when the angle is larger, the height of the guide fin 15 is set higher.

[0048] like Figure 1 As shown, the airway 1 includes three airway parts, which are an inlet airway 11 , a middle airway 12 and an outlet airway 13 . The inlet airway 11 and the outlet airway 13 are located on the same side of the middle airway 12 .

[0049] The channel cross section of the air inlet duct 11 is the same and adopts a circular cross section;

[0050] The channel cross section of the intermediate air channel 12 is the same, and adopts a rectangular cross section with four corners having arc-shaped chamfers. One end of the intermediate air channel 12 is connected to one end of the intake air channel 11 through a first connecting corner 141;

[0051] The channel cross section of the outlet air channel 13 is the same, and adopts a circular cross section. The outlet end of the outlet air channel 13 is connected to the other end of the inlet air channel 11 through the second connecting corner 142;

[0052] The inner walls of the first connecting corner 141 and the second connecting corner 142 are both provided with guide fins 15 whose directions are adapted to the central axes of the corresponding connecting corners.

[0053] With this arrangement, the inlet air duct 11 has the same channel cross-section, the middle air duct 12 has the same channel cross-section, and the outlet air duct 13 has the same channel cross-section, which can ensure that the gas flow speed in each air duct part remains basically unchanged, and the inlet air duct 11 and the middle air duct 12, and the middle air duct 12 and the outlet air duct 13 are connected through a connecting corner, and an arc-shaped channel with an adaptive angle setting is used inside the connecting corner, so that the inlet air duct 11 and the middle air duct 12, and the middle air duct 12 and the outlet air duct 13 with an angle can have a smooth transition, thereby reducing the possibility of gas vortexes at the angle; and the inner wall of the connecting corner is provided with a guide fin 15 with a direction adapted to the central axis of the connecting corner, so that the gas is smoother when it makes a large turn; Figure 2 and Figure 3As shown, the above method significantly improves the gas renewal efficiency in the internal gas channel of the sensor 3, avoids the problem of low gas renewal efficiency caused by the retention of gas inside the sensor 3 and the pressure fluctuation caused by the gas flow, makes the detection gas smoother, and the detection gas is renewed faster in the airway 1, so that the performance of the same sensor 3 product on different instruments is basically the same.

[0054] In this embodiment, one of the airway parts is used to set up an ionization chamber 2, which has an ionization cavity. The ionization cavity is used to ionize the gas. The ionization cavity has an air inlet and an air outlet, and the air inlet and the air outlet are respectively connected to the two ends of the airway part.

[0055] like Figure 4-Figure 5 As shown, the middle air passage 12 is arranged inside the sensor 3, the air inlet 11 and the air outlet 13 are connected to the outside of the sensor 3 respectively, the ionization chamber 2 is arranged in the middle air passage 12, the cross section of the middle air passage 12 is a rectangular cross section, and the four corners of the rectangular cross section have arc-shaped chamfers, the ionization chamber 2 includes an ionization chamber body 21 and an inner needle 22, the inner needle 22 is arranged in the ionization chamber body 21, the inner wall of the ionization chamber body 21 and the inner needle 22 are high and low potentials respectively, and an electromagnetic field is formed between the inner wall of the ionization chamber body 21 and the inner needle 22, which serves as an ionization cavity; the ionization chamber body 21 is provided with an air inlet and an air outlet on the left and right sides, which are connected to the ionization cavity and the left and right parts of the middle air passage 12 respectively; an ionization lamp 23 (such as an ultraviolet lamp) is provided at one end of the ionization chamber body 21, which can provide energy to ionize the detection gas entering the ionization cavity, and then separate it under the action of the electromagnetic field.

[0056] The cross section of the middle air channel 12 for setting the ionization chamber is a rectangular cross section, which can better set the ionization chamber, facilitate the embedding of the ionization chamber, meet the scheme that is not convenient for the circular cross section to be combined in the integrated structure design, and ensure the sealing performance to avoid leakage at the location where the ionization chamber is set; the four corners of the rectangular cross section have arc guide angles to reduce the generation of eddy currents, retention, pollutant retention or dead corners, etc., and can improve the smoothness of gas flow. The rest of the air channel adopts a circular cross section to reduce the generation of eddy currents, retention, pollutant retention or dead corners, etc., and can improve the smoothness of gas flow.

[0057] This structural arrangement makes it relatively simple to arrange the airway 1 in the sensor 3. The detection gas can quickly enter the ionization chamber 2 in the middle airway 12 from the air inlet 11 for detection, and then leave from the air outlet 13. The channel cross-sections of the air inlet 11, the middle airway 12, and the outlet 13 are the same, which can ensure that the gas flow speed in each airway part remains basically unchanged. The air inlet 11 and the middle airway 12, and the middle airway 12 and the outlet 13 are connected through a connecting corner. The interior of the connecting corner adopts an arc-shaped channel, so that the air inlet 11 and the middle airway 12, and the middle airway 12 and the outlet 13 with an angle are connected. The channels 13 can all transition smoothly, thereby reducing the possibility of gas vortexes at the angles; and the inner wall of the connecting corner is provided with a guide fin 15 whose direction is adapted to the central axis of the connecting corner. Even if the cross-section of the intermediate airway is different from that of the inlet airway and the outlet airway, the gas can still be smoother when it turns sharply; the above method significantly improves the gas renewal efficiency in the gas channel inside the sensor 3, avoids the problem of low gas renewal efficiency caused by the retention of gas inside the sensor 3 and the pressure fluctuation caused by the gas flow, makes the detection gas smoother, and the detection gas is updated faster in the airway 1, so that the same sensor 3 product has basically the same performance on different instruments.

[0058] Almost all of the gas entering the airway 1 actively enters the ionization cavity of the ionization chamber 2 for ionization, and then leaves, increasing the total ionization amount of the gas in the airway 1. Compared with the method in which the sampling gas freely diffuses into the ionization chamber 2 for ionization, the present application sets the ionization chamber 2 on the path that the detection gas must pass through, and will not affect the entry and discharge of the detection gas. The ozone ions in the space inside the ionization chamber 2 are discharged along with the detection gas, thereby improving the ionization effect; and the introduced detection gas can be basically ionized, thereby making the amount of ionized gas larger in the same time, the positively charged ions obtained by ionization are more, and the electrical signal obtained by ionization is stronger, so that the sensor 3 has a high response sensitivity, and the result data is consistent with the actual concentration of the gas being measured, so that the detection result is more accurate.

[0059] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An air channel structure of a sensor, characterized in that: The airway includes an airway in the sensor, wherein the airway includes a plurality of airway parts and a connecting corner, wherein the connecting corner connects two adjacent airway parts having an included angle; The cross-sectional area of ​​each airway segment did not vary by more than ±10%; An arc-shaped passage is provided inside the connecting corner.

2. The air channel structure of a sensor according to claim 1, characterized in that: All channels in each airway section have the same cross-sectional area.

3. The air channel structure of a sensor according to claim 1, characterized in that: An arc-shaped passage is used to connect the interior of the corner.

4. The air channel structure of a sensor according to claim 1, characterized in that: When there is an angle between two adjacent airway parts and the angle is greater than or equal to 30 degrees, guide fins are provided on the inner wall of the connecting angle between the two adjacent airway parts, and the direction of the guide fins is adapted to the central axis of the connecting angle.

5. The air channel structure of a sensor according to claim 1, characterized in that: All channels of each airway section have the same cross-section.

6. The air channel structure of a sensor according to claim 5, characterized in that: The centers of all the channel cross sections of the airway portion are located on the same straight line, and the centers of all the channel cross sections of all the airway portions are located on the same plane.

7. The air channel structure of a sensor according to claim 6, characterized in that: All channel cross sections are identical for all airway sections.

8. An air channel structure of a sensor according to any one of claims 1 to 6, characterized in that: One of the airway parts is used to set an ionization chamber, which has an ionization cavity. The ionization cavity is used to ionize gas. The ionization cavity has an air inlet and an air outlet, and the air inlet and the air outlet are respectively connected to the two ends of the airway part.

9. The air channel structure of a sensor according to claim 8, characterized in that: The cross section of the airway portion used for setting the ionization chamber is a rectangular cross section, the four corners of the rectangular cross section have arc chamfers, and the cross section of the remaining airway portion is circular.

10. The air channel structure of a sensor according to claim 9, characterized in that: The airway includes three airway parts, which are an inlet airway, a middle airway and an outlet airway. The inlet airway and the outlet airway are located on the same side of the middle airway, and the ionization chamber is arranged in the middle airway. The channel cross-sections of the intake air ducts are the same; The channel cross-sections of the intermediate air passages are the same, and one end of the intermediate air passages is connected to one end of the intake air passage via a connecting corner; The channel cross-sections of the outlet air passages are the same, and the outlet end of the outlet air passages is connected to the other end of the inlet air passage through a connecting corner; The inner wall of the connecting corner is provided with guide fins whose direction matches the central axis of the connecting corner.

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