Conductivity sensor packaging method, conductivity sensor and temperature-salinity-depth measuring instrument

Abstract

The present invention discloses a conductivity sensor packaging method, a conductivity sensor and a temperature-salinity-depth measuring instrument. Before the traditional glue-filling packaging is performed, wax-immersion packaging is specially performed on the outside of the sensor housing. After the two packagings are completed, heating and wax removal are performed to form a cavity interlayer between the packaging glue layer and the housing. After the cavity interlayer is filled with thermally conductive silicone oil, the drainage hole is blocked, and the entire conductivity sensor packaging process is completed. The present invention is easy to operate. The conductivity sensor formed by the packaging method is filled with thermally conductive silicone oil between the packaging glue layer and the housing. The thermally conductive silicone oil is located on the outer circle of the outer wall of the housing. When the outside of the packaging glue layer is subjected to pressure, the housing can be provided with force buffering, so that the deformation of the entire conductivity sensor is uniform, thereby solving the problem of inaccurate measurement caused by uneven deformation of the conductivity sensor under high pressure. The thermally conductive silicone oil can also make the conductivity sensor quickly sense temperature, make the measurement more accurate, and further improve the measurement accuracy.

Description

Technical Field

[0001] The invention belongs to the field of test and measurement technology, and relates to the research of temperature-salinity-depth measurement technology, and in particular to a conductivity sensor packaging method, a conductivity sensor and a temperature-salinity-depth measuring instrument. Background Art

[0002] Seawater temperature, salinity and depth characterize the physical and electromagnetic properties of seawater and are the most basic observation elements in the physical oceanography of the abyss. The research on the high-precision and rapid response conductivity temperature and depth (CTD) measurement technology for submersible platforms at full sea depth will not only provide the necessary environmental information for the underwater maneuvering and safe operation of submersible platforms, but also provide key data for the study of material exchange and biological characteristics of the abyssal edge water, revealing deep-sea turbulent mixing and internal circulation of the ocean, etc.

[0003] The conductivity sensor in the existing temperature, salinity and depth measuring instrument is packaged using a one-time potting process. This structure is used in shallow water within 2000 meters, and the measurement difference is not large. However, at a depth of more than 2000 meters, the conductivity sensor is prone to structural deformation under high pressure, and the compression deformation is dispersed and uneven. Therefore, its pressure compensation is difficult to control, and the compensation coefficient cannot be consistent, resulting in inaccurate measurement. Based on this, the present invention proposes a new conductivity sensor packaging solution to overcome the above problems. Summary of the invention

[0004] The purpose of the present invention is to provide a conductivity sensor packaging method, a conductivity sensor and a temperature-salinity-depth measuring instrument to solve the problem that the above-mentioned existing conductivity sensors are packaged using a one-time potting process, and are deformed unevenly under high pressure, thereby causing inaccurate measurements and large errors.

[0005] To achieve the above-mentioned purpose, the present invention provides a conductivity sensor packaging method, comprising the following steps: S1, connecting an extension line to an electrode inside a shell of the conductivity sensor, and passing the extension line through the side wall of the shell; S2, sealing the ports at both ends of the shell with rubber plugs, and then performing wax dipping packaging on the conductivity sensor to form a packaging wax layer on the outside of the shell; S3, removing the rubber plugs at the ports at both ends of the shell, and performing glue pouring packaging on the conductivity sensor to form a packaging glue layer on the outside of the packaging wax layer; and a drainage hole is reserved on the packaging glue layer; S4, heating the outside of the packaging glue layer to melt the packaging wax layer and drain it through the drainage hole to form a cavity interlayer between the packaging glue layer and the shell; S5, filling the cavity interlayer with thermal conductive silicone oil, and sealing the drainage hole after filling.

[0006] In some implementations, in step S1, the electrode is connected to the extension wire by welding.

[0007] In some implementations, in step S2, when the conductivity sensor is encapsulated by wax immersion, the conductivity sensor is vertically immersed in liquid paraffin.

[0008] In some embodiments, the operation process of step S3 includes the steps of: S31, removing the rubber plugs at the ports at both ends of the shell; S32, cutting the encapsulation wax layer at the ports at both ends of the shell so that the axial ends of the encapsulation wax layer are not longer than the axial ends of the shell; S33, after placing the conductivity sensor into the encapsulation mold, placing a silicone threaded plug on the outside of one end of the shell; S34, closing the mold and pouring glue to cover the outside of the encapsulation wax layer to form the encapsulation glue layer; S35, demolding and taking out the conductivity sensor, and removing the silicone threaded plug to form the drainage hole at the end of the encapsulation glue layer.

[0009] In some implementations, in step S33, before placing the conductivity sensor into the packaging mold, O-rings are respectively mounted on the outside of both ends of the housing.

[0010] In some embodiments, the operation process of step S4 includes the steps of: S41, placing the conductivity sensor in an air box with the drainage hole facing downward; S42, heating the outside of the packaging glue layer to 60°C~70°C and keeping it warm for at least 30 minutes to melt the packaging wax layer and drain it through the drainage hole.

[0011] In some implementations, in step S5, a syringe is used to fill the cavity interlayer with thermally conductive silicone oil, and after filling, a threaded rubber plug or a bellows is used to seal the drainage hole.

[0012] In some embodiments, the encapsulation wax layer has a thickness of 0.8 mm to 1.2 mm.

[0013] The present invention further proposes a conductivity sensor, which is packaged using any of the conductivity sensor packaging methods described above, wherein a packaging glue layer is packaged outside a shell of the conductivity sensor, and thermal conductive silicone oil is filled between the packaging glue layer and the outer wall of the shell.

[0014] The present invention also provides a temperature-salinity-depth measuring instrument, comprising the above conductivity sensor.

[0015] Compared with the prior art, the present invention has achieved the following technical effects: the conductivity sensor packaging method proposed in the present invention specifically performs wax dipping packaging on the outside of the sensor housing before the traditional glue filling packaging is performed. After the two packagings are completed, the wax is removed by heating to form a cavity interlayer between the packaging glue layer and the housing. After the cavity interlayer is filled with thermal conductive silicone oil, the drainage hole is blocked, and the entire conductivity sensor packaging process is completed. The present invention is easy to operate. The conductivity sensor formed by the packaging method is filled with thermal conductive silicone oil between the packaging glue layer and the housing. The thermal conductive silicone oil is located on the outer circle of the outer wall of the housing. When the outside of the packaging glue layer is subjected to pressure, the housing can be provided with force buffering, so that the deformation of the entire conductivity sensor is uniform, thereby solving the problem of inaccurate measurement caused by uneven deformation of the conductivity sensor under high pressure. In addition, the thermal conductive silicone oil can also make the conductivity sensor quickly sense temperature, make the measurement more accurate, and further improve the measurement accuracy of the sensor.

[0016] The conductivity sensor proposed in the present invention is packaged based on the above conductivity sensor packaging method. Thermal conductive silicone oil is filled between the packaging glue layer and the shell. The thermal conductive silicone oil is located on the outer circle of the outer wall of the shell. When the outside of the packaging glue layer is under pressure, it can provide force buffering for the shell to make the deformation of the entire conductivity sensor uniform, thereby solving the problem of inaccurate measurement caused by uneven deformation of the conductivity sensor under high pressure. In addition, the thermal conductive silicone oil can also make the conductivity sensor quickly sense temperature, make the measurement more accurate, and further improve the measurement accuracy of the sensor.

[0017] The temperature-salinity-depth measuring instrument proposed in the present invention includes the above-mentioned conductivity sensor and has all the characteristics of the above-mentioned conductivity sensor, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 This is an operation flow chart of the conductivity sensor packaging method disclosed in an embodiment of the present invention.

[0020] Figure 2 Schematic diagram of the packaging structure of the original three-electrode conductivity sensor.

[0021] Figure 3 A schematic diagram of the packaging structure of a three-electrode conductivity sensor disclosed in an embodiment of the present invention.

[0022] Figure 4The figure is a schematic diagram of the use of the packaging mold disclosed in the embodiment of the present invention.

[0023] Figure 5 This is the 70MPa stress deformation analysis diagram (total deformation) of the original three-electrode conductivity sensor.

[0024] Figure 6 This is a 70MPa stress deformation analysis diagram (static stress analysis diagram) of the three-electrode conductivity sensor disclosed in an embodiment of the present invention.

[0025] Figure 7 This is a thermal strain diagram (volume change) of the three-electrode conductivity sensor disclosed in an embodiment of the present invention from 25°C to 1.5°C.

[0026] In the figure, the reference numerals are: 1, conductivity sensor; 2, housing; 3, electrode installation position; 4, packaging mold; 5, silicone threaded plug; 6, thermal conductive silicone oil; 7, packaging glue layer; 8, flange. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] One of the purposes of the present invention is to provide a novel conductivity sensor packaging method to solve the problem that the existing conductivity sensor is packaged using a one-time potting process and deforms unevenly under high pressure, resulting in inaccurate measurement and large errors.

[0029] Another object of the present invention is to provide a conductivity sensor packaged based on the above conductivity sensor packaging method.

[0030] Another object of the present invention is to provide a temperature-salinity-depth measuring instrument comprising the above-mentioned conductivity sensor.

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Example 1: Figure 1 and Figure 3As shown, this embodiment proposes a conductivity sensor packaging method, including the following steps: S1, connecting an extension line to the internal electrode of the shell 2 of the conductivity sensor 1, and passing the extension line through the side wall of the shell 2; S2, after sealing the ports at both ends of the shell 2 with rubber plugs, immersing the entire conductivity sensor in liquid paraffin, and then quickly taking it out, after the paraffin solidifies, coating the outside of the shell 2 to form a packaging wax layer, and completing the wax immersion packaging. In the above operation, the role of the rubber plug is to seal the two ends of the shell 2 to prevent the liquid paraffin from entering the interior of the shell 2; S3, after the wax immersion packaging is completed, remove the rubber plugs at the ports at both ends of the shell 2, and repair The encapsulation wax layer on the outside of the entire housing 2 is formed so that the encapsulation wax layer only covers the outer wall of the housing 2 and does not affect the two end ports of the housing 2; then the conductivity sensor that has been wax-sealed once is encapsulated by a second encapsulation process to form an encapsulation glue layer 7 on the outside of the encapsulation wax layer, and a drainage hole is reserved on the encapsulation glue layer 7; S4, the outside of the encapsulation glue layer 7 is heated to melt the encapsulation wax layer and drain it through the reserved drainage hole to form a cavity sandwich between the encapsulation glue layer 7 and the housing 2; S5, the aforementioned cavity sandwich is filled with thermal conductive silicone oil 6, and the drainage hole is blocked after filling to prevent leakage of the thermal conductive silicone oil 6. The above-mentioned conductivity sensor packaging method, before the traditional encapsulation packaging is performed, wax dipping is specially performed on the outside of the sensor housing. After the two encapsulations are completed, heating and wax removal are performed to form a cavity sandwich between the encapsulation glue layer 7 and the housing 2. After the cavity sandwich is filled with thermal conductive silicone oil 6, the drainage hole is blocked, and the entire conductivity sensor packaging process is completed. The conductivity sensor 1 formed by the packaging method has a thermally conductive silicone oil 6 filled between the packaging glue layer 7 and the shell 2. The thermally conductive silicone oil 6 is located on the outer circle of the outer wall of the shell 2. When the packaging glue layer 7 is subjected to pressure, it can provide force buffering for the shell 2, so that the deformation of the entire conductivity sensor 1 is uniform, thereby solving the problem of inaccurate measurement caused by uneven deformation of the conductivity sensor under high pressure. In addition, the thermally conductive silicone oil 6 can make the conductivity sensor quickly sense temperature, make the measurement more accurate, and further improve the measurement accuracy of the sensor.

[0033] In some embodiments, the conductivity sensor to which the above conductivity sensor packaging method can be applied includes but is not limited to the existing three-electrode conductivity sensor. The housing 2 of the three-electrode conductivity sensor is generally a cylindrical glass tube, which is hollow inside and open at both ends, and an electrode installation position 3 for electrode installation is provided inside the cylindrical glass tube; for the three-electrode conductivity sensor, three groups of electrodes are generally arranged along the axial direction inside the housing 2. Seawater flows in through the opening at one end of the housing 2 and flows out through the opening at the other end. In the process of flowing through the inside of the housing 2, each electrode completes the detection of the conductivity of the seawater; the above-mentioned three-electrode conductivity sensor is an existing finished product, and its structure and working principle are not described in detail here.

[0034] The structure of the traditional three-electrode conductivity sensor after packaging is as follows Figure 2 As shown, the outer wall of the housing 2 is directly encapsulated to form an encapsulation adhesive layer 7, that is, the outer wall of the housing 2 is in direct contact with the encapsulation adhesive layer 7. Based on the above conductivity sensor encapsulation method of the present application, the structure of the three-electrode conductivity sensor after encapsulation is as follows Figure 3 As shown, thermal conductive silicone oil 6 is also filled between the packaging glue layer 7 and the shell 2. The thermal conductive silicone oil 6 is located on the outer circle of the outer wall of the shell 2. When the packaging glue layer 7 is subjected to external force, it can provide force buffering for the shell 2 so that the entire conductivity sensor 1 is subjected to uniform force.

[0035] In some embodiments, preferably in step S1, the electrode is connected to the extension wire by welding, and the extension wire is electrically connected to the electrode. The extension wire is generally encapsulated in the encapsulation glue layer 7, and the flange 8 provided at the end of the encapsulation glue layer 7 extends out to be electrically connected to other electrical components in the temperature-salinity-depth measuring instrument.

[0036] In some embodiments, preferably in step S2, when the conductivity sensor with rubber plugs at both ends is encapsulated by wax dipping, the conductivity sensor is vertically immersed in liquid paraffin as a whole, and quickly taken out after being completely immersed, and after the paraffin solidifies, an encapsulation wax layer with a thickness of 0.8 mm to 1.2 mm is formed. In actual operation, the thickness of the encapsulation wax layer can be 0.8 mm, 1 mm or 1.2 mm, among which 1 mm is the best.

[0037] In some embodiments, the operation process of step S3 is preferably performed as follows: S31, removing the rubber plugs at the ports at both ends of the housing 2; S32, cutting the packaging wax layer at the ports at both ends of the housing 2 so that the axial ends of the packaging wax layer are not longer than the axial ends of the housing 2; S33, after placing the conductivity sensor into the packaging mold 4, placing a silicone threaded plug 5 ( Figure 4 The black solid area in the figure is the silicone threaded plug 5, which is arranged opposite to the flange 8); S34, mold closing and glue pouring to form a packaging glue layer 7 on the outside of the packaging wax layer; S35, demoulding and taking out the conductivity sensor, and removing the silicone threaded plug 5 to form a drainage hole at the end of the packaging glue layer 7 that penetrates the wall thickness direction of the packaging glue layer 7. Generally, one drainage hole is reserved on the packaging glue layer 7. It should be noted that the packaging mold 4 used in step S33 and the packaging process and packaging principle of the packaging glue layer 7 are mature technologies, and will not be described in detail here.

[0038] In some embodiments, preferably in step S33, before placing the conductivity sensor into the encapsulation mold 4, O-rings are respectively mounted on the outer ends of the housing 2. In actual operation, preferably, after the encapsulation wax layer is cut, its two ends are respectively shorter than the axial ends of the housing 2, and the O-rings are mounted on the portion of the housing 2 that extends out of the encapsulation wax layer. The O-rings can be used to ensure that the ends of the formed encapsulation adhesive layer 7 are sealed with the ends of the housing 2, and after the encapsulation is completed, the O-rings are encapsulated inside the encapsulation adhesive layer 7.

[0039] In some embodiments, the operation process of step S4 is preferably performed according to the following steps: S41, place the conductivity sensor in an air box with the drain hole facing downward, and place a container such as a paper cup directly below the drain hole to receive the melted wax liquid; S42, heat the outside of the encapsulating adhesive layer 7 to 60°C~70°C, and keep it warm for at least 30 minutes to melt the encapsulating wax layer and drain it through the drain hole. In actual operation, it is preferred to use a high-temperature air box to heat the encapsulating adhesive layer 7, that is, place the conductivity sensor encapsulated with the encapsulating adhesive layer 7 into the high-temperature air box with the drain hole facing downward, and place a container such as a paper cup directly below the drain hole; then start the high-temperature air box, set the corresponding temperature and time to complete the heating and melting of the wax layer inside the encapsulating adhesive layer 7.

[0040] In some embodiments, preferably in step S5, a syringe is used to fill the cavity interlayer with thermal conductive silicone oil 6, and after filling, a threaded rubber plug or a bellows is used to seal the drainage hole, thereby forming a conductivity sensor 1 with a novel packaging structure, such as Figure 3 shown.

[0041] In summary, the conductivity sensor packaging method proposed in this scheme achieves the purpose of uniform pressure change of the conductivity sensor based on secondary packaging and thermal conductive silicone oil injection technology. The technical effect and technical principle of the conductivity sensor packaging method proposed in this scheme are specifically described below.

[0042] The shell of the three-electrode conductivity sensor is made of glass. Due to the large pressure in the deep sea, the deformation of the glass tube cannot be ignored, so pressure compensation is required during conductivity measurement. Figure 2 The sensor structure shown in the figure is subjected to 70MPa pressure simulation analysis. Figure 5 As shown, only the encapsulation glue layer 7 causes the conductivity sensor to be subjected to uneven pressure and nonlinear deformation. Although pressure compensation is performed through the ideal model, it does not coincide with the actual deformation, resulting in a large maximum allowable error in the conductivity sensor measurement. In order to obtain higher accuracy, the conductivity sensor needs to be designed with a uniform pressure change.

[0043] By using the conductivity sensor packaging method proposed in this solution, the conductivity sensor is packaged twice, and the inside of the packaging glue layer 7 is filled with thermal conductive silicone oil, which can ensure that each point between the electrodes in the glass tube (i.e., the sensor housing) is under the same pressure, and the glass tube wall will not be unevenly stressed due to the unilateral force of the external elastic colloid (i.e., the packaging glue layer 7), thereby avoiding local damage to the sensor under high pressure. Figure 6As shown, the conductivity sensor prepared by the conductivity sensor packaging method of this scheme is subjected to 70MPa pressure simulation analysis (the figure represents the static displacement change in the static stress analysis). The glass tube wall is subjected to uniform force, which is completely equivalent to the force on the glass tube of a pure conductivity cell. The mechanical properties are repeatable and calculable, which facilitates the establishment of a pressure compensation algorithm and pressure compensation correction, thereby compensating for the change in the conductivity cell constant and improving the sensor measurement accuracy. The principle of pressure compensation correction is as follows.

[0044] The conductivity sensor uses a three-electrode conductivity cell as the sensitive element. By measuring the seawater resistance R between the electrodes c The change of seawater resistance and conductivity is measured by measuring the seawater conductivity C. The relationship between seawater resistance and conductivity is:

[0045] R c =K / C ----------------Formula 1

[0046] In the formula, R c is the seawater resistance between the electrodes, C is the conductivity, and K is the conductivity cell constant, which is expressed as

[0047] K=L / S ----------------Formula 2

[0048] Where L is the length between the electrodes of the conductivity cell, and S is the cross-sectional area of ​​the conductivity cell. c The seawater conductivity C can be obtained.

[0049] Under pressure, the conductivity C is affected by the change of the conductivity cell and pressure compensation is required.

[0050] For a cube under hydrostatic force, the mechanical formula is

[0051] ΔL / L =-P(1-2μ) / E ---------------Formula 3

[0052] Since this relationship is linear in force and displacement, the strain relationship also applies to the length, radius, and wall thickness of the cylinder.

[0053] Therefore, under pressure, the conductivity calculation formula should be

[0054] C P =L P / S / R C =[L 0 (1+ΔL / L 0 )] / [S(1+Δ r / r 0 ) 2 ] / R C =C 0 / (1+ΔL / L0 ) --------------Formula 4

[0055] Combining the above formulas, we can conclude

[0056] C P = C 0 / [1-P(1-2μ) / E]= C 0 / (1-9.4*10 -8 *P), pressure compensation coefficient P cor =-9.4*10 -8 .

[0057] Among them C P is the conductivity after pressure correction, C 0 The current shell 2 is made of glass, and its elastic modulus E is 6.38×10 10 Pa; Poisson's ratio μ is 0.2; P is the current pressure, unit ×10 4 Pa.

[0058] Similarly, when the temperature changes, due to thermal expansion and contraction, the size of the conductivity cell will also change slightly, and this change cannot be ignored. Figure 7 Shown is the thermal strain diagram of the conductivity cell from 25℃ to 1.5℃ (the diagram represents the volume change).

[0059] According to the thermodynamic formula analysis:

[0060] ΔL / L =α*ΔT--------------------------Equation 5

[0061] C T =L T / S / R C =[L 0 (1+ΔL / L 0 )] / [S(1+Δ r / r 0 ) 2 ] / R C =C 0 / (1+ΔL / L 0 )=C 0 / (1+α*ΔT)-------------Equation 6

[0062] Among them C T is the conductivity after temperature change, C 0 is the conductivity at 0℃, ΔT is the difference between temperature and 0℃, in ℃, the current shell 2 is glass, and its thermal expansion coefficient is α 20~300 =(3.33*10 -6 ) / ℃.

[0063] C T = C 0 / (1+α*ΔT)=C 0 / (1+3.33*10 -6 *ΔT), temperature compensation coefficient T cor is 3.33*10 -6 .

[0064] In practical applications, temperature and pressure are coupled, so the change in the conductivity cell size is a coupled variable between the two. In summary, C TP =C 0 / (1+3.33*10 -6 *ΔT-9.4*10 -8 *P). Where C 0 is the conductivity at 0℃ and zero pressure, ΔT is the difference between temperature and 0℃, in ℃, and P is the current pressure, in ×10 4 Pa.

[0065] Therefore, this solution is based on secondary packaging and thermal conductive silicone oil filling technology, which can not only make the deformation caused by pressure uniform, but also make the conductivity sensor quickly sense temperature and make the measurement more accurate.

[0066] The above technical effects of this scheme are experimentally verified and explained below.

[0067] Example 1: Use a special tool and a high-precision pressure calibrator to test the pressure effect of the pressure-varying conductivity sensor made by the above conductivity sensor packaging method. Connect the tool and one of the pressure pipes of the pressure calibrator, place it in a high-precision constant temperature water tank, and control the temperature based on the actual temperature value of 0℃~2℃ at a water depth of 7000 meters, and perform conductivity tests under different pressures. The test results are shown in Table 1.

[0068] Table 1 Conductivity measurement values ​​under different pressures

[0069]

[0070] After pressure and temperature compensation correction, the results are shown in Table 2.

[0071] Table 2 Conductivity measurement correction values ​​under different pressures

[0072]

[0073] Comparative Example 1: The specific operation is the same as in Example 1 above. Figure 2 The traditional conductivity sensor shown is installed in a special tooling and connected to another pressure tube of the pressure calibrator. It is placed in a high-precision constant temperature water tank and compared with the pressure-varying conductivity sensor. The test results are shown in Table 3 below.

[0074] Table 3 Conductivity measurement values ​​under different pressures

[0075]

[0076] After pressure and temperature compensation correction, the results are shown in Table 4.

[0077] Table 4 Conductivity measurement correction values ​​under different pressures

[0078]

[0079] Comparing Table 2 with Table 4, it can be seen that the conductivity measurement value of the pressure-varying conductivity sensor is closer to the true value.

[0080] Embodiment 2: This embodiment provides a conductivity sensor 1, such as Figure 3 As shown, it is packaged by the conductivity sensor packaging method of Example 1, the outer shell 2 of the conductivity sensor is packaged with a packaging glue layer 7, and the space between the packaging glue layer 7 and the outer wall of the shell 2 is filled with thermal conductive silicone oil 6.

[0081] The conductivity sensor 1 of this embodiment may specifically be a three-electrode conductivity sensor, and its technical effects may refer to those of Embodiment 1, which will not be described in detail here.

[0082] Embodiment 3: This embodiment provides a temperature-salinity-depth measuring instrument, which includes and is installed with the conductivity sensor 1 of Embodiment 2.

[0083] It should be noted that the structures, proportions, sizes, etc. drawn in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change of the proportional relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. The change or adjustment of their relative relationship should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0084] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A conductivity sensor packaging method, characterized in that: The method comprises the following steps: S1, connecting an extension line to an electrode inside a housing (2) of a conductivity sensor, and passing the extension line through a side wall of the housing (2); S2, sealing the ports at both ends of the housing (2) with rubber plugs, and then encapsulating the conductivity sensor with wax to form an encapsulation wax layer on the outside of the housing (2), wherein the thickness of the encapsulation wax layer is 0.8 mm to 1.2 mm; S3, removing the rubber plugs at the ports at both ends of the housing (2), and encapsulating the conductivity sensor with glue to form an encapsulation glue layer (7) on the outside of the encapsulation wax layer; and the encapsulation glue layer (7) is reserved with drainage holes; the operation process of step S3 comprises the following steps: S31, removing the rubber plugs at the ports at both ends of the housing (2); S32, cutting the encapsulation wax layer at the ports at both ends of the housing (2) so that the axial ends of the encapsulation wax layer are not longer than the axial ends of the housing (2); S33, placing the conductivity sensor into the encapsulation mold (4), and then A silicone threaded plug (5) is placed on the outer side of one end of the shell (2); S34, mold closing and glue pouring to cover the outside of the packaging wax layer to form the packaging glue layer (7); S35, demoulding and taking out the conductivity sensor, and removing the silicone threaded plug (5) to form the drainage hole at the end of the packaging glue layer (7); S4, heating the outside of the packaging glue layer (7) to melt the packaging wax layer and drain it through the drainage hole to form a cavity sandwich between the packaging glue layer (7) and the shell (2); S5, filling the cavity sandwich with thermal conductive silicone oil (6), and sealing the drainage hole after filling.

2. The conductivity sensor packaging method according to claim 1, characterized in that: In step S1, the electrode is connected to the extension line by welding.

3. The conductivity sensor packaging method according to claim 1, characterized in that: In step S2, when the conductivity sensor is encapsulated by wax immersion, the conductivity sensor is vertically immersed in liquid paraffin.

4. The conductivity sensor packaging method according to claim 1, characterized in that: In step S33, before placing the conductivity sensor into the packaging mold (4), O-rings are respectively mounted on the outside of both ends of the housing (2).

5. The conductivity sensor packaging method according to any one of claims 1 to 3, characterized in that: The operation process of step S4 comprises the following steps: S41, placing the conductivity sensor in an air box with the drainage hole facing downward; S42, heating the outside of the packaging glue layer (7) to 60°C-70°C and keeping the temperature for at least 30 minutes, so that the packaging wax layer melts and is drained through the drainage hole.

6. The conductivity sensor packaging method according to any one of claims 1 to 3, characterized in that: In step S5, a syringe is used to fill the cavity interlayer with thermally conductive silicone oil (6), and after the filling, a threaded rubber plug or a bellows is used to seal the drainage hole.

7. A conductivity sensor, characterized in that: The conductivity sensor is packaged by the conductivity sensor packaging method according to any one of claims 1 to 6, wherein a packaging glue layer (7) is packaged outside the housing (2) of the conductivity sensor, and thermal conductive silicone oil (6) is filled between the packaging glue layer (7) and the outer wall of the housing (2).

8. A temperature-salinity-depth measuring instrument, characterized in that: Comprising the conductivity sensor (1) as claimed in claim 7.

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