Gas measurement probe

Abstract

A gas measurement probe, comprising a housing and a measurement element. The housing comprises a first housing; the first housing has a first inner cavity and two or more first through holes; the first inner cavity is an open cavity; the measurement element comprises a first thermistor; the first thermistor is located in the first inner cavity; the first housing has a top wall and a side wall; the top wall and the side wall are both located on the periphery of the first inner cavity; in a first direction of the gas measurement probe, the side wall is at least partially close to the measurement element relative to the top wall; and at least two first through holes are both located on the top wall; alternatively, at least one first through hole is located on the side wall, and at least one first through hole is located on the top wall. By means of two or more first through holes, the flux between gas in the first inner cavity and external gas is increased, and the first thermistor can quickly sense a temperature change caused by the gas, thereby shortening the response time of the gas measurement probe.

Description

Gas detection probes

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on July 28, 2023, with application number 202310940478.1 and invention name “Gas Detection Probe”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of measurement technology, and in particular to a gas detection probe. Background Art

[0003] The gas detection probe includes a detection element and a housing. The housing comprises a first shell with an opening. The detection element includes a first thermistor. The first shell has a first inner cavity. When the detected gas enters the first inner cavity through the opening of the first shell, the resistance value of the first thermistor changes with the changes in the gas. When the flow rate between the first inner cavity and the external gas is low, the first thermistor senses the gas changes more slowly, and the resistance value changes more slowly, resulting in a longer response time for the gas detection probe.

[0004] Summary of the Invention

[0005] In order to solve the above technical problems, the present application provides a gas detection probe with a short response time.

[0006] A first aspect of the present application provides a gas detection probe, comprising a housing and a detection element, wherein the housing comprises a first housing having a first inner cavity and two or more first through holes, wherein the first through holes are in communication with the first inner cavity, and the first through holes are in communication with the outside of the gas detection probe;

[0007] The detection element includes a first thermistor, and the first thermistor is located in the first inner cavity;

[0008] The first housing includes a top wall and a side wall, and the top wall and the side wall are both located at the periphery of the first inner cavity; the gas detection probe has a first direction, and along the first direction, the side wall is at least partially close to the detection element relative to the top wall;

[0009] More than two of the first through holes are located on the top wall; or at least one of the first through holes is located on the side wall, and at least one of the first through holes is located on the top wall.

[0010] The gas detection probe in the first aspect of the present application has two or more first through holes on the top wall of the first shell, or both the top wall and the side wall have first through holes, so that the flow rate between the first inner cavity gas and the external gas is increased, and the first thermistor can quickly sense the temperature changes caused by the gas, thereby shortening the response time of the gas detection probe.

[0011] A second aspect of the present application provides a gas detection probe, comprising a housing and a detection element, wherein the housing comprises a first housing having a first inner cavity, and the detection element comprises a first thermistor located in the first inner cavity;

[0012] The first housing includes a top wall and a side wall, and the top wall and the side wall are both located at the periphery of the first inner cavity; the gas detection probe has a first direction, and along the first direction, the side wall is at least partially close to the detection element relative to the top wall;

[0013] The first shell has a first through hole, the first through hole is connected to the first inner cavity, and the first through hole is connected to the outside of the gas detection probe;

[0014] The first through hole is arranged on the top wall, and the flow area of ​​the first through hole accounts for 20% to 70% of the area of ​​the top wall; or the first through hole is arranged on the side wall, and the flow area of ​​the first through hole accounts for 20% to 70% of the area of ​​the side wall.

[0015] In the second aspect of the present application, the gas detection probe has a first through hole arranged on the top wall, and the flow area of ​​the first through hole accounts for 20% to 70% of the top wall area; or, the first through hole is arranged on the side wall, and the flow area of ​​the first through hole accounts for 20% to 70% of the side wall area. In the present application, the flow area of ​​the first through hole accounts for more than 20%, so that the flow rate between the first inner cavity gas and the external gas increases, and the first thermistor can quickly sense the temperature change caused by the gas, shortening the response time of the gas detection probe. At the same time, the flow area of ​​the first through hole accounts for less than 70%, which can reduce the impact of external heat radiation on the first thermistor. In other words, the present application limits the flow area of ​​the first through hole to the range of 20% to 70%, which can reduce the impact of external heat radiation on the first thermistor while shortening the response time of the gas detection probe. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG1 is a schematic diagram of a gas detection probe provided in one embodiment of the present application;

[0017] FIG2 is a schematic diagram of an explosion of a gas detection probe provided in one embodiment of the present application;

[0018] FIG3 is a schematic diagram of an explosion of a gas detection probe provided by an embodiment of the present application from another perspective;

[0019] FIG4 is a cross-sectional view of a gas detection probe provided in one embodiment of the present application;

[0020] FIG5 is a schematic diagram of a gas detection probe provided in another embodiment of the present application;

[0021] FIG6 is a cross-sectional view of the gas detection probe provided in FIG5 ;

[0022] FIG7 is a projection diagram of a gas detection probe provided in one embodiment of the present application;

[0023] FIG8 is a schematic diagram of a projection of a first through hole and a first thermistor of a gas detection probe provided in one embodiment of the present application. DETAILED DESCRIPTION

[0024] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0025] It should be understood that the embodiments described are only a portion of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0026] Currently, the relevant gas detection probe 1 includes a housing 2 and a detection element 3. The housing 2 includes a first housing 21, which has a first inner cavity 211. The first inner cavity 211 is an open cavity. When the gas to be detected enters the open cavity, it causes the resistance of the first thermistor 31 in the first inner cavity 211 to change. When the resistance changes to a set value, it triggers the propagation of an electrical signal, issuing an alarm prompt, thereby achieving the effect of gas detection. The flow rate of the gas to be detected when entering the first inner cavity 211 will affect the response speed of the gas detection probe 1.

[0027] To improve the response speed of a gas detection probe 1, the present application provides a gas detection probe 1. As shown in FIG1 and FIG3 , a first housing 21 includes a first inner cavity 211 and two or more first through-holes 212. The first through-holes 212 communicate with the first inner cavity 211 and with the outside of the gas detection probe 1. The detection element 3 includes a first thermistor 31, which is located in the first inner cavity 211. The first housing 21 includes a top wall 213 and side walls 214, both of which are located outside the first inner cavity 211. The gas detection probe 1 has a first orientation H, which is parallel to the height of the gas detection probe 1. Along the first orientation H, at least a portion of the side walls 214 are closer to the detection element 3 than to the top wall 213. At least two first through-holes 212 are located in the top wall 213; alternatively, at least one first through-hole 212 is located in the side wall 214, and at least one first through-hole 212 is located in the top wall 213. When the top wall 213 has two or more first through holes 212, the flow rate between the first inner cavity 211 and the outside air is increased, allowing the first thermistor 31 to quickly sense temperature changes caused by the gas, thereby reducing the response time of the gas detection probe 1. Similarly, when the side walls 214 and the top wall 213 each have one or two or more first through holes 212, the flow rate between the first inner cavity 211 and the outside air is also increased, thereby improving the response speed of the gas detection probe 1.

[0028] For the thermal conductivity gas detection probe 1 of the present application, if the flow area of ​​the first through hole 212 is too small, the time for external gas to diffuse into the first inner cavity 211 is long, and the response speed is slow; and if the flow area of ​​the first through hole 212 is too large, the resistance of the first thermistor 31 of the first inner cavity 211 is easily affected by external gas convection and thermal radiation, which may cause the probe to falsely report an alarm. In other words, the flow area of ​​the first through hole 212 cannot be too large or too small. By providing two or more first through holes 212 in the first shell 21, the present application can increase the flow area between the first inner cavity 211 and the outside of the gas detection probe 1 while ensuring that the impact of external gas convection and external thermal radiation on the first thermistor 31 is small, which is beneficial to improving the response speed of the gas detection probe 1 while ensuring the detection accuracy of the gas detection probe 1. Or it can be understood that the related technology only provides one through hole with a flow area of ​​C for connecting the first inner cavity 211 and the outside of the gas detection probe 1. Compared with the related technology, this solution reduces the flow area of ​​a single first through hole 212 by increasing the number of first through holes 212 when the total flow area remains unchanged, that is, when the sum of the flow areas of all first through holes 212 is C. Therefore, under the premise of ensuring that the response time is not affected or the impact is small, the convection between the outside of the gas detection probe 1 and the first inner cavity 211 and the impact of external thermal radiation on the first thermistor 31 are reduced, thereby improving the detection accuracy of the gas detection probe 1.

[0029] In one embodiment, as shown in FIG2 , when all the first through holes 212 are located on the top wall 213, the first through holes 212 are symmetrically arranged on the top wall 213. Furthermore, optionally, the symmetrical arrangement refers to an arrangement in a centrally symmetrical or axisymmetric manner. For example, when there are four first through holes 212, and the first top wall 213 is circular, the axis of symmetry can be any diameter of the circle, and the first through holes 212 are evenly distributed on both sides of the axis of symmetry; at the same time, the axis of symmetry can also be multiple diameters of the circle, and the first through holes 212 are evenly distributed near or on the axis of symmetry. When the first top wall 213 is square, the axis of symmetry can be a diagonal line, and the first through holes 212 are evenly distributed on both sides of the axis of symmetry; at the same time, the axis of symmetry can also be multiple diagonals, and the first through holes 212 are evenly distributed around or on the axis of symmetry.

[0030] When there are five first through holes 212, one of the first through holes 212 can be disposed on the first top wall 213, and the other four first through holes 212 can be disposed on the side wall 214. The first through holes 212 are preferably polygonal, circular, or multi-angled.

[0031] To enable the first thermistor 31 to more quickly sense gas changes and perform rapid detection, in one embodiment, as shown in FIG7 , a plane perpendicular to the first direction H is defined as a projection plane S. Along the first direction H, the orthographic projection of the hole wall corresponding to the first through hole 212 on the projection plane S is a first projection S1. The orthographic projection of the first thermistor 31 on the projection plane S is a second projection S2. The second projection S2 is at least partially located within the outline of the first projection S1. In other words, the first thermistor 31 is at least partially aligned with the first through hole 212.

[0032] When the first shell 21 is a square body, the four first through holes 212 can be set on the four side walls 214 of the square body. Further, at least part of the first thermistor 31 can be respectively aligned with the four first through holes 212. In order to improve the detection accuracy of the gas detection probe 1, in one embodiment, as shown in Figure 4, the shell 2 includes a second shell 22, the second shell has a second inner cavity 221, and the second inner cavity 221 is a closed cavity; the detection element 3 includes a second thermistor 32, the second thermistor 32 is located in the second inner cavity 221, and the second thermistor 32 serves as a reference resistor in the second inner cavity 221. When the first thermistor 31 and the second thermistor 32 reach a certain resistance difference, the gas detection probe 1 will sound an alarm. Furthermore, in one embodiment, the first thermistor 31 and the second thermistor 32 are both NTC (negative temperature coefficient) thermistor chips, which facilitates component selection.

[0033] In order to reduce the impact of the external gas temperature on the second thermistor 32, thereby affecting the detection accuracy of the gas detection probe 1, in one embodiment, as shown in FIG5, there is a gap between the first shell 21 and the second shell 22. Alternatively, in one embodiment, as shown in FIG5, the first shell 21 and the second shell 22 are integrally formed, and the shell 2 includes a connecting wall 23, and the first shell 21 and the second shell 22 are both connected to the connecting wall 23. In some embodiments, the first shell 21 and the second shell 22 are cylindrical or square, or other shapes. Furthermore, a spacing groove 20 is provided between the first shell 21 and the second shell 22; along the first direction H, the connecting wall 23 is away from the top wall 213 relative to the spacing groove 20, and the size of the spacing groove 20 in the first direction H is larger than the size of the connecting wall 23 in the first direction H, so that the spacing groove 20 isolates the heat conduction between the shared partition wall of the first shell 21 and the second shell 22, thereby further improving the detection accuracy of the gas detection probe 1.

[0034] In one embodiment, as shown in FIG6 , the dimension of the spacing groove 20 in the first direction H of the gas detection probe 1 is h1, and the dimension of the connecting wall 23 in the first direction H of the gas detection probe 1 is h2, where h1 and h2 satisfy the following relationship: 2≤h1 / h2≤4. When the dimension of the spacing groove 20 in the first direction H is at least twice and less than four times the dimension of the connecting wall 23 in the first direction H, heat transfer between the first inner cavity 211 and the second inner cavity 221 is further reduced, thereby further improving the detection accuracy of the gas detection probe 1 while also taking into account the connection strength of the spacing groove 20. Preferably, h1 / h2 = 3, which achieves both reduced heat transfer between the first inner cavity 211 and the second inner cavity 221 and sufficiently strong connection strength between the first shell 21 and the second shell 22.

[0035] The second aspect of the present application provides a gas detection probe 1, wherein the first through hole 212 is provided on the top wall 213, and the flow area of ​​the first through hole 212 accounts for 20% to 70% of the area of ​​the top wall 213, or the first through hole 212 is provided on the side wall 214, and the flow area of ​​the first through hole 212 accounts for 20% to 70% of the area of ​​the side wall 214. The area of ​​the top wall 213 is the area of ​​the entire top wall 213, including the area of ​​the first through hole 212; the area of ​​the side wall 214 is the area of ​​the entire unfolded surface of the side wall 214, including the area of ​​the first through hole 212. For example, when the first shell 21 is a cylindrical shell, the top wall 213 is a circle with a radius of R, the height of the first shell 21 is l, and the area of ​​the top wall 213 is πR 2 , the area of ​​the side wall 214 is 2πR·l; the aperture corresponding to the first through hole 212 is d, and the flow area of ​​the first through hole 212 is πd 2 / 4. In this application, d 2 / 4R 2 The range is 20% to 70%. As shown in Figure 3, when the top wall 213 has a first through hole 212 and the flow area of ​​the first through hole 212 accounts for 20% to 70% of the area of ​​the top wall 213, when the flow area of ​​the first through hole 212 is large, the flow rate of gas in the first inner cavity 211 and the external gas increases, and the first thermistor 31 can quickly sense the temperature change caused by the gas, shortening the response time of the gas detection probe 1. At the same time, the flow area of ​​the first through hole 212 is limited, reducing the impact of external heat radiation on the first thermistor 31 caused by the excessive flow area of ​​the first through hole 212, causing the gas detection probe 1 to have a false alarm. Furthermore, the flow area of ​​the first through hole 212 accounts for 30% to 60% of the area of ​​the top wall 213. Similarly, when the side wall 214 has a first through hole 212 and the flow area of ​​the first through hole 212 accounts for 20% to 70% of the area of ​​the side wall 214, the gas detection probe 1 can also respond quickly when encountering the detection gas and issue an alarm; further, the flow area of ​​the first through hole 212 accounts for 30% to 60% of the area of ​​the side wall 214.

[0036] Furthermore, while controlling the flow area of ​​the first through holes 212, more than two first through holes 212 can be provided. When the first through holes 212 are provided on the top wall 213, the total flow area of ​​all the first through holes 212 accounts for 20% to 70% of the area of ​​the top wall 213; or when the first through holes 212 are provided on the side wall 214, the total flow area of ​​all the first through holes 212 accounts for 20% to 70% of the area of ​​the side wall 214. This can shorten the response time of the gas detection probe 1 while ensuring the detection accuracy of the gas detection probe 1, so that the detection accuracy and response speed of the gas detection probe 1 can meet the requirements at the same time.

[0037] The following describes in detail the case where the gas detection probe 1 of the present application has at least two first through holes 212 .

[0038] In some embodiments, the at least two first through holes 212 include a first sub-through hole 2121 and a second sub-through hole 2122. Along the first direction H, the orthographic projection of the hole wall corresponding to the first sub-through hole 2121 on the projection plane S is a first sub-projection S11, and the orthographic projection of the hole wall corresponding to the second sub-through hole 2122 on the projection plane S is a second sub-projection S12. Both the first sub-projection S11 and the second sub-projection S12 are located outside the outer contour of the second projection S2, or in other words, both the first sub-projection S11 and the second sub-projection S12 are located around the second projection S2. For example, as shown in FIG8 , the orthographic projections of the four first through holes 212 on the projection plane S surround the orthographic projection S2 of the first thermistor 31 on the projection plane S.

[0039] In some embodiments, the first sub-projection S11 and the second sub-projection S12 are symmetrically arranged about the center of the second projection S2. Specifically, the first sub-projection S11 and the second sub-projection S12 are symmetrically arranged about the center O of the second projection S2.

[0040] In some embodiments, the flow areas of at least two first through holes 212 are equal.

[0041] In order to further enable the first thermistor 31 to sense gas changes more quickly and perform rapid detection, in one embodiment, as shown in FIG. 3 , the first thermistor 31 is at least partially aligned with the first through hole 212 .

[0042] In one embodiment, as shown in Figure 3, the gas detection probe 1 includes a base 4, the base 4 has a third through hole 41 and a second through hole 42, the detection element 3 includes a second mounting portion 391 and a first mounting portion 392, the second mounting portion 391 includes a second step 3912 and a second protrusion 3911, the first mounting portion 392 includes a first step 3922 and a first protrusion 3921, the second protrusion 3911 protrudes from the second mounting portion 391 in a direction away from the second mounting portion 391, and the first protrusion 3921 protrudes from the first mounting portion 392 in a direction away from the first mounting portion 392.

[0043] The first housing 21 is at least partially located in the third through-hole 41, and the second housing 22 is at least partially located in the second through-hole 42. The second mounting portion 391 is at least partially located in the third through-hole 41, and the first mounting portion 392 is at least partially located in the second through-hole 42. To facilitate installation, the second step 3912 is at least partially connected to the wall of the third through-hole 41, and the first step 3922 is at least partially connected to the wall of the second through-hole 42. The second protrusion 3911 and the first protrusion 3921 serve as positioning elements.

[0044] In one embodiment, as shown in FIG3 , the first housing 21 includes a first flange portion 215 , which is located adjacent to the first mounting portion 392 relative to the first through hole 212 . Along the first direction H, at least a portion of the first mounting portion 392 and the top wall 213 are located on either side of the first inner cavity 211 . The second housing 22 includes a top 222 , a side portion 223 , and a second flange portion 224 . The top 222 and the side portion 223 are located on the periphery of the second inner cavity 221 . Along the first direction H, at least a portion of the second mounting portion 391 and the top 222 are located on either side of the second inner cavity 221 . The side portion 223 is at least partially located adjacent to the detection element 3 relative to the top 222 , and the second flange portion 224 is located adjacent to the second mounting portion 391 relative to the top 222 . The first mounting portion 392 has a first end surface 3923 connected to the first step 3922 and further away from the top wall 213 than the first step 3922. The second mounting portion 391 has a second end surface 3913 connected to the second step 3912 and further away from the top 222 than the second step 3912. To ensure a more sealed installation, the first flange portion 215 is sealed to the first end surface 3923, and the second flange portion 224 is sealed to the second end surface 3913. The sealing connection methods include welding, sealing adhesive connection, or connection via a sealing ring.

[0045] In some embodiments, the first mounting portion 392 is fixedly connected to the first housing 21. The first flange portion 215 is welded to the first end surface 3923 via resistance welding. In other words, the first mounting portion 392 is welded to the first housing 21 via resistance welding or friction welding. Compared to gluing, resistance welding can reduce the impact of volatilization of adhesives or other fluxes on the detection process.

[0046] As shown in FIG3 , the detection element 3 includes first leads 34a, 34b and first conductive terminals 36a, 36b. Portions of the first conductive terminals 36a, 36b are located on the same side of the first mounting portion 392 as the first leads 34a, 34b and the first thermistor 31. Portions of the first conductive terminals 36a, 36b, along with the first leads 34a, 34b and the first thermistor 31, are located on either side of the first mounting portion 392. The first conductive terminals 36a, 36b extend through the first mounting portion 392 and are fixedly connected to the first mounting portion 392. The first thermistor 31 is electrically connected to the first leads 34a, 34b, which are in turn electrically connected to the first conductive terminals 36a, 36b. The detection element 3 includes second leads 33a and 33b, second conductive terminals 35a and 35b, and a portion of the second conductive terminals 35a and 35b located on the same side of the second mounting portion 391 as the second thermistor 32. Portions of the second conductive terminals 35a and 35b and the second thermistor 32 are located on opposite sides of the second mounting portion 391. First conductive terminals 36a and 36b extend through the first mounting portion 392. The second thermistor 32 is electrically connected to the second leads 33a and 33b, which are in turn electrically connected to the second conductive terminals 35a and 35b.

[0047] In order to make the connection between the first leads 34a, 34b and the first conductive terminals 36a, 36b more secure, as shown in Figure 3, the first leads 34a, 34b include a first connecting portion 3a, and the first leads 34a, 34b and the first conductive terminals 36a, 36b are connected through the first connecting portion 3a. When the first connecting portion 3a is linear, the connection between the first leads 34a, 34b and the first conductive terminals 36a, 36b is a linear connection; when the first connecting portion 3a is planar, the connection between the first leads 34a, 34b and the first conductive terminals 36a, 36b is a planar connection. Similarly, the second leads 33a, 33b include a second connecting portion 3b, and the second leads 33a, 33b are connected to the second conductive terminals 35a, 35b through the second connecting portion 3b. When the second connecting portion 3b is linear, the connection between the second leads 33a, 33b and the second conductive terminals 35a, 35b is a linear connection. When the second connecting portion 3b is planar, the connection between the second leads 33a, 33b and the second conductive terminals 35a, 35b is a planar connection. In one embodiment, planar connection is preferred.

[0048] The first leads 34a and 34b include first electrodes 34a1 and 34b1, and the second leads 33a and 33b include second electrodes 33a1 and 33b1. The first electrodes 34a1 and 34b1 and the second electrodes 33a1 and 33b1 can be made of a material with low thermal conductivity, such as Constantan alloy, which is a copper-nickel alloy composed of 55% copper and 45% nickel (Cu). 55 Ni 45 ) and is characterized by its resistance to temperature changes and high resistivity. It has a low temperature coefficient of resistivity and a medium resistivity (resistivity of 0.48μΩ·m).

[0049] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and intent of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A gas detection probe, comprising a housing and a detection element, wherein: The housing comprises a first housing, the first housing having a first inner cavity and two or more first through holes, the first through holes being in communication with the first inner cavity, and the first through holes being in communication with the outside of the gas detection probe; The detection element includes a first thermistor, and the first thermistor is located in the first inner cavity; The first shell includes a top wall and a side wall, and the top wall and the side wall are both located at the periphery of the first inner cavity; The gas detection probe has a first direction, along which the side wall is at least partially close to the detection element relative to the top wall; The at least two or more first through holes are all located on the top wall; or, at least one first through hole is located on the side wall, and at least one first through hole is located on the top wall.

2. The gas detection probe according to claim 1, wherein: More than two of the first through holes are located on the top wall, and the first through holes are symmetrically arranged on the top wall.

3. The gas detection probe according to claim 1, wherein: A plane perpendicular to the first direction is defined as a projection plane. Along the first direction, the orthographic projection of the hole wall corresponding to the first through hole on the projection plane is a first projection. The orthographic projection of the first thermistor on the projection plane is a second projection. The second projection is at least partially located within the outline of the first projection.

4. The gas detection probe according to claim 1, wherein: The two or more first through holes include a first sub-through hole and a second sub-through hole; A plane perpendicular to the first direction is defined as a projection plane. Along the first direction, the orthographic projection of the hole wall corresponding to the first sub-through hole on the projection plane is a first sub-projection, the orthographic projection of the hole wall corresponding to the second sub-through hole on the projection plane is a second sub-projection, the orthographic projection of the first thermistor on the projection plane is a second projection, the first sub-projection and the second sub-projection are both outside the outer contour of the second projection, and the first sub-projection and the second sub-projection are both located on the peripheral side of the second projection.

5. The gas detection probe according to claim 4, wherein: The first sub-projection and the second sub-projection are arranged symmetrically about the second projection center; The flow areas of the at least two first through holes are equal.

6. The gas detection probe according to claim 1, wherein: The housing comprises a second housing, the second housing has a second inner cavity, and the second inner cavity is a closed cavity; The detection element includes a second thermistor, and the second thermistor is located in the second inner cavity; There is a distance between the first shell and the second shell; or, the first shell and the second shell are an integral piece, the shell comprises a connecting wall, and the first shell and the second shell are both connected to the connecting wall.

7. The gas detection probe according to claim 6, wherein: A spacing groove is provided between the first shell and the second shell; Along the first direction, the connecting wall is away from the top wall relative to the spacing groove, and a size of the spacing groove in the first direction is greater than a size of the connecting wall in the first direction.

8. The gas detection probe according to claim 7, wherein: The dimension of the spacing groove in the first direction is h1, and the dimension of the connecting wall in the first direction is h2, wherein h1 and h2 satisfy the following relationship: 2≤h1 / h2≤4.

9. A gas detection probe, comprising a housing and a detection element, wherein: The housing comprises a first housing, the first housing has a first inner cavity, the detection element comprises a first thermistor, and the first thermistor is located in the first inner cavity; The first shell includes a top wall and a side wall, and the top wall and the side wall are both located at the periphery of the first inner cavity; The gas detection probe has a first direction, along which the side wall is at least partially close to the detection element relative to the top wall; The first shell has a first through hole, the first through hole is connected to the first inner cavity, and the first through hole is connected to the outside of the gas detection probe; The first through hole is arranged on the top wall, and the flow area of ​​the first through hole accounts for 20% to 70% of the area of ​​the top wall; or the first through hole is arranged on the side wall, and the flow area of ​​the first through hole accounts for 20% to 70% of the area of ​​the side wall.

10. The gas detection probe according to claim 9, wherein: The first thermistor is at least partially aligned with the first through hole.

11. The gas detection probe according to claim 9, wherein: The housing comprises a second housing, the second housing has a second inner cavity, and the second inner cavity is a closed cavity; The detection element includes a second thermistor, the second thermistor is located in the second cavity; There is a distance between the first shell and the second shell; or, the first shell and the second shell are an integral piece, the shell comprises a connecting wall, and the first shell and the second shell are both connected to the connecting wall.

12. The gas detection probe according to claim 11, wherein: A spacing groove is provided between the first shell and the second shell; Along the first direction, the connecting wall is away from the top wall relative to the spacing groove, and a size of the spacing groove in the first direction is greater than a size of the connecting wall in the first direction.

13. A gas detection probe, comprising a first housing and a detection element, wherein the detection element comprises a first thermistor, wherein: The first housing has a first inner cavity, and the first thermistor is located in the first inner cavity; The first shell has at least two first through holes, and the at least two first through holes are both connected to the first inner cavity, and the at least two first through holes are both connected to the outside of the gas detection probe; The first housing comprises a top wall and a side wall, and the top wall and the side wall are both located at the periphery of the first inner cavity; the gas detection probe has a first direction, and along the first direction, the side wall is at least partially close to the first thermistor relative to the top wall; The at least two first through holes are both arranged on the top wall, and the sum of the flow areas of the at least two first through holes accounts for 20% to 70% of the area of ​​the top wall; or, the at least two first through holes are arranged on the side wall, and the sum of the flow areas of the at least two first through holes accounts for 20% to 70% of the area of ​​the side wall.

14. The gas detection probe according to claim 13, wherein: The at least two first through holes include a first sub-through hole and a second sub-through hole; A plane perpendicular to the first direction is defined as a projection plane. Along the first direction, the orthographic projection of the hole wall corresponding to the first sub-through hole on the projection plane is a first sub-projection, the orthographic projection of the hole wall corresponding to the second sub-through hole on the projection plane is a second sub-projection, the orthographic projection of the first thermistor on the projection plane is a second projection, the first sub-projection and the second sub-projection are both outside the outer contour of the second projection, and the first sub-projection and the second sub-projection are both located on the peripheral side of the second projection.

15. The gas detection probe according to claim 14, wherein: The first sub-projection and the second sub-projection are arranged symmetrically about the second projection center.

16. The gas detection probe according to claim 13, wherein: The flow areas of the at least two first through holes are equal.

17. The gas detection probe according to any one of claims 13 to 16, wherein: The detection element includes a first lead, a first conductive terminal and a first mounting portion, the first thermistor is electrically connected to the first lead, and the first lead is electrically connected to the first conductive terminal; The first mounting portion is fixedly connected to the first housing, along the first direction, at least a portion of the first mounting portion and the top wall are respectively located on two sides of the first inner cavity, the first conductive terminal is arranged through the first mounting portion, and the first conductive terminal is fixedly connected to the first mounting portion; Along the first direction, a portion of the first conductive terminal, the first lead and the first thermistor are located on the same side of the first mounting portion, and a portion of the first conductive terminal and the first thermistor are located on two sides of the first mounting portion respectively.

18. The gas detection probe according to claim 17, wherein: The first mounting portion and the first shell are welded by resistance welding or friction welding.

19. The gas detection probe according to claim 17, wherein: The first lead is connected to the first conductive terminal by wire or surface connection.

20. The gas detection probe according to claim 13, wherein: The gas detection probe comprises a second shell, the second shell has a second inner cavity, and the second inner cavity is a closed cavity; The detection element comprises a second thermistor, and the second thermistor is located in the second inner cavity; the first thermistor and the second thermistor are both negative temperature coefficient thermistors.

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