Mounting structure of large-area film sensor for strain test

Abstract

The utility model discloses a mounting structure of a large-area thin film sensor for a strain test. The mounting structure comprises a mounting adhesive, a protective adhesive and an adhesive tape, the bottom of the large-area thin film sensor is adhered to the surface of the to-be-mounted surface through mounting glue, the mounting glue between the test area and the to-be-mounted surface adopts surface mounting glue or a glue film, and the mounting glue between the circuit area and the to-be-mounted surface adopts fixing glue; the protective glue covers the top of the large-area film sensor and completely wraps the top and the side face of the whole large-area film sensor, and the adhesive tape covers the outside of the protective glue and completely wraps the outside of the whole protective glue. A regional installation mode is adopted, the circuit area is fixed by fixing glue which is easy to use, and the test area is installed by surface mount glue which needs to be pressurized, heated and cured, so that the test precision is ensured, the area which needs to be pressurized and heated is reduced, the problem that large-area pressurization and heating are needed when a meter-scale sensor is integrally mounted is avoided, and the installation speed is improved.

Description

Technical Field

[0001] The utility model belongs to the field of thin film sensors and relates to a mounting structure of a large-area thin film sensor for strain testing. Background Art

[0002] Both resistance strain gauges and large-area thin-film sensors are sensitive elements used for strain testing, and their materials, process flows, and subsequent application methods are generally the same. Resistance strain gauges are relatively small in size (≤20cm×20cm), while large-area thin-film sensors are mostly "meter-level" in size; resistance strain gauges are mostly used for short-term stress testing in relatively good or harsh environments, while large-area thin-film sensors must meet the requirements of long-term stable operation in outdoor environments. Therefore, a complete set of mounting and protection structures for large-area thin-film sensors is required to meet the use requirements of the sensor.

[0003] However, the current installation structure of large-area thin-film sensors has the problem that large-area pressurization and heating are required when the "meter-level" sensor is mounted as a whole, which makes installation inconvenient, time-consuming and labor-intensive. Utility Model Content

[0004] The purpose of the utility model is to overcome the shortcomings of the installation structure in the above-mentioned prior art, such as inconvenient installation, time-consuming and labor-intensive installation, and to provide an installation structure for a large-area thin film sensor for strain testing, which reduces the area required for pressurization and heating and improves installation efficiency.

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

[0006] A mounting structure for a large-area thin-film sensor for strain testing, comprising mounting glue, protective glue, a glue-blocking film and adhesive tape;

[0007] The bottom of the large-area thin-film sensor is glued to the surface of the installation surface by means of mounting glue. The mounting glue between the test area and the installation surface adopts patch glue or adhesive film, and the mounting glue between the circuit area and the installation surface adopts fixed glue. The protective glue covers the top of the large-area thin-film sensor, and the protective glue completely wraps the top and sides of the entire large-area thin-film sensor. The outside of the protective glue is covered with tape, and the tape completely wraps the entire outside of the protective glue.

[0008] Preferably, when installing on a concrete surface, a primer glue is provided between the bottom of the mounting glue and the surface to be installed.

[0009] Furthermore, the bonding strength between the primer and the concrete is ≥2.5MPa, the tensile elastic modulus is ≥3Gpa, the elongation is ≥1%, the thickness is 1mm to 5mm, and the area is 1.5 to 3 times the area of ​​the large-area thin film sensor.

[0010] Preferably, when patch adhesive is used, the thickness is 0.5 mm to 1 mm, and when adhesive film is used, the thickness is 5 to 15 μm. The area of ​​the patch adhesive is 1.5 to 3 times the area of ​​the test area.

[0011] Preferably, the material of the protective adhesive is butyl adhesive film, liquid butyl rubber, room temperature vulcanized silicone rubber or polyamide adhesive.

[0012] Preferably, the thickness of the protective glue is 2 mm to 5 mm.

[0013] Preferably, a glue-blocking film is provided between the top of the test area and the protective glue, and the material of the glue-blocking film is polytetrafluoroethylene, polyester or polyimide film.

[0014] Preferably, the thickness of the adhesive resistance film is 20 μm to 100 μm, and the area of ​​the adhesive resistance film is 1.5 to 2 times the area of ​​the test area.

[0015] Preferably, the edge of the tape exceeds the edge of the protective tape by 5 cm to 10 cm.

[0016] Compared with the prior art, the utility model has the following beneficial effects:

[0017] The utility model adopts a zoned installation method. The line area is fixed with easy-to-use fixing glue, and the test area is installed with a patch glue that requires pressurization and heat curing. While ensuring the test accuracy, the area that needs to be pressurized and heated is reduced, avoiding the problem of large-area pressurization and heating when the "meter-level" sensor is mounted as a whole, and improving the installation speed.

[0018] Furthermore, providing a primer can effectively resist moisture and isolate the influence of moisture and water vapor that may come into contact from the installation surface to the cover surface.

[0019] Furthermore, a resist film is used to isolate the protective adhesive layer from the test area, so as to prevent the protective adhesive layer from sticking to the test area and affecting the test data.

[0020] Furthermore, the sensor is wrapped with a highly weather-resistant base layer and protective layer to ensure long-term stable operation in harsh outdoor environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of a large-area thin-film sensor of the utility model;

[0022] Figure 2 This is a schematic diagram of the installation structure of the large-area thin-film sensor of the utility model;

[0023] Figure 3 This is a flow chart for installing a large-area thin-film sensor of the utility model;

[0024] Figure 4This is a curve diagram of sensor test data changes during the day in an outdoor environment of the utility model.

[0025] Among them: 1-circuit area; 2-test area; 3-priming glue; 4-fixing glue; 5-patch glue; 6-protective glue; 7-resistance film; 8-aluminum foil tape; 9-surface to be installed. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments; based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0027] It should be noted that the words "front", "rear", "left", "right", "up" and "down" used in the following description refer to directions in the drawings, and the words "inside" and "outside" refer to directions toward or away from the geometric center of a specific component, respectively.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0029] In the installation structure of the large-area thin-film sensor for strain testing described in the utility model, Figure 1 As shown, the large-area thin-film sensor includes two parts: a test area 2 and a circuit area 1.

[0030] In this embodiment, a plurality of test areas 2 are arranged at various positions of the large-area thin-film sensor, and the remaining area of ​​the large-area thin-film sensor is the circuit area 1 .

[0031] like Figure 2 As shown, the bottom of the large-area thin-film sensor is glued to the surface of the mounting surface 9 by mounting glue, wherein the mounting glue between the test area 2 and the mounting surface 9 adopts the patch glue 5 or the adhesive film, and the mounting glue between the circuit area 1 and the mounting surface 9 adopts the fixed glue 4. The mounting glue can use either liquid glue or solid adhesive film.

[0032] The installation method is divided into different areas: the line area 1 is fixed with glue or tape that is easy to use, does not require heating, and can be fixed by hand pressure; the test area 2 is installed with special patch glue 5 that needs to be pressurized and heated for curing. While ensuring the test accuracy, the problem of large-area pressurization and heating when the "meter-level" sensor is mounted as a whole is avoided.

[0033] When installing on a concrete surface, a primer 3 is provided between the bottom of the mounting glue and the surface to be installed 9, which effectively resists moisture and isolates the influence of moisture and water vapor that may come into contact from the installation surface to the cover surface, thereby preventing water seepage in the concrete from causing failure of large-area thin-film sensors.

[0034] The top of the large-area thin-film sensor is covered with a protective glue 6 as a protective layer. The protective glue 6 completely wraps the entire top of the large-area thin-film sensor. The protective glue 6 can be made of either liquid glue or solid glue film.

[0035] The outside of the protective adhesive 6 is covered with an aluminum foil tape 8 , and the aluminum foil tape 8 completely wraps the entire outside of the protective adhesive 6 .

[0036] like Figure 3 As shown, the large-area thin-film sensor is installed according to the following structure, starting from the surface to be installed, in order: ① Primer 3 (used when installed on a concrete surface, not on a metal surface) → ② Mounting Glue → ③ Large-area Thin-film Sensor → ④ Protective Glue 6 → ⑤ Aluminum Foil Tape 8. The above installation method can ensure the long-term stable operation of the large-area thin-film sensor in harsh outdoor environments.

[0037] The primer 3 used must be a special epoxy repair glue for concrete. The glue must meet the characteristics of small filler particles, easy to scrape, no flow after application, no shrinkage after curing, high weather resistance and good resistance to medium erosion. At the same time, the bonding strength between the glue and concrete should be ≥2.5MPa, the tensile elastic modulus should be ≥3Gpa, and the elongation should be ≥1%. Before primer, use tools to roughly level the installation surface 9 to remove protrusions and impurities. When primer, the glue thickness is controlled at 1mm~5mm, and the glue area is controlled at 1.5 times to 3 times the area of ​​the large-area thin film sensor. Bake at room temperature or heat according to the curing conditions until solidified, and then use tools to finely polish until it can be pasted.

[0038] The patch glue 5 used should be epoxy, acrylic patch glue 5, or adhesive film that cures at room temperature or ≤80°C. When using adhesive film, its thickness should be 5 to 15μm. When applying glue, only apply it to the patch position of the test area 2 on the large-area thin film sensor, and the thickness of the glue should be controlled at 0.5mm to 1mm. The area of ​​the adhesive film and the glue application should be controlled at 1.5 to 3 times the area of ​​the test area 2. Press the sensor test area 2 on the glue application area, and pressurize at room temperature or heat and pressurize until it cures according to the curing conditions.

[0039] At the same time as the patch, use hot melt adhesive, nail-free adhesive or double-sided tape to flatten and fix the circuit area 1 on the large-area thin-film sensor on the surface to be installed.

[0040] The protective glue 6 used should be one of the highly weather-resistant butyl film, liquid butyl rubber, room temperature vulcanized silicone rubber and polyamide glue. When using the film, its thickness should be 2mm to 5mm. When applying the glue, the thickness of the glue should be controlled at 2mm to 5mm. The film and glue application area should be controlled at 1.5 to 3 times the area of ​​the primer 3. And it should be baked at room temperature or heated according to the curing conditions until it is cured. If the fluidity of the glue liquid is relatively large, it needs to be applied 2 to 5 times, and each application needs to wait until the last glue layer is cured.

[0041] In order to prevent the thick protective glue 6 layer from sticking to the test area 2 and affecting the test results, a resist film 7 can be used in the test area 2 to separate the test area 2 from the protective glue 6. The resist film 7 used can be one of polytetrafluoroethylene, polyester and polyimide films with a thickness of 20μm to 100μm. The area of ​​the resist film 7 is controlled to be 1.5 times to 2 times the area of ​​the large-area thin film sensor test area 2.

[0042] Finally, a layer of aluminum foil tape 8 is applied to the entire installation area, and the edge of the aluminum foil tape 8 should extend 5 cm to 10 cm beyond the edge of the protective adhesive 6, thereby forming an installation structure for a large-area thin-film sensor.

[0043] The large-area thin-film sensor is wrapped with a highly weather-resistant base layer and protective layer, ensuring the long-term stable operation of the sensor in harsh outdoor environments.

[0044] The installation process of the large-area thin-film sensor installation structure for strain testing is as follows:

[0045] First, treat the surface to be installed. If the surface is a metal surface, use 300-400 mesh sandpaper to grind off the coating and rust until the metal color is exposed, then cross-grind at 45 degrees to create the texture, and wipe off the surface powder with anhydrous ethanol or acetone to complete the treatment. If the surface is a concrete surface, it is necessary to waterproof and level the surface. The specific method is: use a masonry chisel, a concrete rough planer + diamond grinding disc, etc. to remove the protrusions and impurities on the concrete surface, and wipe off the surface powder with anhydrous ethanol or acetone to perform rough leveling. Then evenly apply 1mm-5mm concrete-specific epoxy repair glue on the rough leveling surface, and control the glue application area to 1.5 times to 3 times the area of ​​the large-area thin-film sensor. The leveling glue is cured at room temperature or baked. Use a concrete rough planer + hard plastic grinding disc to grind the surface of the cured leveling glue, and wipe off the surface powder with anhydrous ethanol or acetone to complete the treatment.

[0046] Secondly, the large-area thin film sensor is mounted. During installation, first apply a layer of low-temperature (≤80°C) curing patch glue 5 to the installation position of the large-area thin film sensor test area 2, and the thickness of the glue is controlled to be 0.5mm~1mm, and the area of ​​the glue is controlled to be 1.5 times~3 times the area of ​​the test area 2; or use a soldering iron to heat press a layer of 5μm~15μm high modulus thermosetting adhesive film at a temperature higher than the softening temperature and lower than the curing temperature, and the area of ​​the adhesive film is controlled to be 1.5 times~3 times the area of ​​the test area 2. Then stick double-sided tape or apply nail-free glue to the large-area thin film sensor circuit area 1, align the large-area thin film sensor test area 2 with the installation position and press it manually until the surface of the large-area thin film sensor is flat and fixed. Next, use a soldering iron and a hot plate to heat press the large-area thin film sensor test area 2 according to the pressure, temperature, and time parameters of the patch glue 5 or the film curing, until the patch glue 5 or the film is completely cured, and the mounting of the large-area thin film sensor is completed.

[0047] Next, the large-area thin-film sensor is protected. First, a rubber-blocking film 7 of about 1.5 to 2 times the area of ​​the large-area thin-film sensor test area 2 is covered. The rubber-blocking film 7 can be made of polytetrafluoroethylene, polyester or polyimide. This step can prevent the subsequent protective glue 6 layer from affecting the test area 2. Then, a 2mm to 5mm butyl sealing film of 1.5 to 3 times the area of ​​the primer 3 is used to cover the entire installation surface, and manually pressed until it is completely fitted. If there is a gap on the edge of the rubber strip, use liquid butyl rubber to seal the edge.

[0048] Finally, use aluminum foil tape 8 to stick on the butyl sealing film. The edge of the aluminum foil tape 8 should exceed the edge of the butyl film by 5 cm to 10 cm, thus completing the installation of the large-area thin-film sensor.

[0049] After installation in the above manner, the large-area thin-film sensor was subjected to high temperature and high humidity treatment at 60°C and 90% RH for 168 hours. The resistance change data of the large-area thin-film sensor before and after the treatment are as follows:

[0050] Table 1 Data record of sensor resistance change after high temperature and high humidity treatment at 60℃ and 90%RH for 168h

[0051]

[0052]

[0053] After outdoor installation in the above manner, remote data observation of the sensor is carried out. The data changes within 6 days are as follows: Figure 4 As shown (the reading interval is 1h), Figure 4 It can be seen that the data fluctuation of the large-area thin-film sensor is within the allowable range.

[0054] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0055] It should be understood that the above description is for illustration and not for limitation. Many embodiments and many applications beyond the examples provided will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of the present teachings should not be determined with reference to the above description, but rather with reference to the foregoing claims and the full scope of equivalents to which such claims are entitled. For the purpose of comprehensiveness, all articles and references, including disclosures of patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended to be a waiver of the subject matter, nor should it be considered that the applicant has not considered the subject matter as part of the disclosed utility model subject matter.

Claims

1. A mounting structure for a large-area thin-film sensor for strain testing, characterized in that: It includes mounting glue, protective glue (6) and adhesive tape; The bottom of the large-area thin-film sensor is adhered to the surface of the mounting surface (9) by mounting glue, the mounting glue between the test area (2) and the mounting surface (9) is made of mounting glue (5) or adhesive film, and the mounting glue between the circuit area (1) and the mounting surface (9) is made of fixing glue (4); the protective glue (6) covers the top of the large-area thin-film sensor, and the protective glue (6) completely wraps the top and sides of the entire large-area thin-film sensor; the outside of the protective glue (6) is covered with adhesive tape, and the adhesive tape completely wraps the entire outside of the protective glue (6).

2. The installation structure of the large-area thin-film sensor for strain testing according to claim 1, characterized in that: When installing on a concrete surface, a primer glue (3) is provided between the bottom of the mounting glue and the surface to be installed (9).

3. The installation structure of the large-area thin-film sensor for strain testing according to claim 2, characterized in that: The bonding strength between the primer (3) and the concrete is ≥2.5MPa, the tensile elastic modulus is ≥3Gpa, the elongation is ≥1%, the thickness is 1mm-5mm, and the area is 1.5 to 3 times the area of ​​the large-area thin film sensor.

4. The installation structure of the large-area thin-film sensor for strain testing according to claim 1, characterized in that: When the patch glue (5) is used, the thickness is 0.5 mm to 1 mm, and when the adhesive film is used, the thickness is 5 to 15 μm. The area of ​​the patch glue (5) is 1.5 to 3 times the area of ​​the test area (2).

5. The installation structure of the large-area thin-film sensor for strain testing according to claim 1, characterized in that: The material of the protective adhesive (6) is butyl adhesive film, liquid butyl rubber, room temperature vulcanized silicone rubber or polyamide adhesive.

6. The installation structure of the large-area thin-film sensor for strain testing according to claim 1, characterized in that: The thickness of the protective glue (6) is 2 mm to 5 mm.

7. The installation structure of the large-area thin-film sensor for strain testing according to claim 1, characterized in that: A glue-blocking film (7) is provided between the top of the test area (2) and the protective glue (6), and the material of the glue-blocking film (7) is polytetrafluoroethylene, polyester or polyimide film.

8. The installation structure of the large-area thin-film sensor for strain testing according to claim 1, characterized in that: The thickness of the adhesive resistance film (7) is 20 μm to 100 μm, and the area of ​​the adhesive resistance film (7) is 1.5 to 2 times the area of ​​the test area (2).

9. The installation structure of the large-area thin-film sensor for strain testing according to claim 1, characterized in that: The edge of the tape extends beyond the edge of the protective adhesive (6) by 5 cm to 10 cm.

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