阅读说明：本技术 一种基于pvdf薄膜的柔性振动传感器及其制备方法 (Flexible vibration sensor based on PVDF (polyvinylidene fluoride) film and preparation method thereof ) 是由 杨成韬 谢易微 孙贤 孙星林 于 2020-03-20 设计创作，主要内容包括：本发明涉及一种基于PVDF薄膜的柔性振动传感器,属于传感技术领域。本发明提出的传感器具有良好的柔韧性、延展性、可自由弯曲甚至折叠,而且结构形式灵活多样,可根据测量物体表面条件的要求任意布置,能够非常方便地对复杂的测量物体表面进行检测,可在生物医疗、桥梁等具有不规则表面的领域发挥重大作用。此外,本发明还涉及一种基于PVDF薄膜的柔性振动传感器的制备方法,该方法适用的薄膜尺寸灵活、能大大缩短薄膜封装成器件的时间,同时也不会对PVDF薄膜造成损伤,且与现有生产工艺相兼容,同时具有封装操作方便、封装耗时短、封装尺寸小、反应灵敏等优点,封装后的PVDF器件可以很好的将接收到的振动信号转化成电荷信号,适于大规模的推广使用。(The invention relates to a flexible vibration sensor based on a PVDF film, belonging to the technical field of sensing. The sensor provided by the invention has good flexibility and ductility, can be freely bent or even folded, has flexible and various structural forms, can be randomly arranged according to the requirements of the surface conditions of the measured object, can conveniently detect the surface of the complex measured object, and can play an important role in the fields with irregular surfaces, such as biological medicine, bridges and the like. In addition, the invention also relates to a preparation method of the PVDF film-based flexible vibration sensor, the method is suitable for the flexible film size, can greatly shorten the time of packaging the film into a device, does not damage the PVDF film, is compatible with the existing production process, and has the advantages of convenient packaging operation, short packaging time consumption, small packaging size, sensitive reaction and the like.)

1. The flexible vibration sensor based on the PVDF film is characterized by comprising a polyimide film (1), a first electrode (2), a second electrode (3), a third electrode (4), the PVDF film (5), a first lead end and a second lead end;

the polyimide film (1) comprises a first part and a second part which are connected with each other, the first electrode (2) is arranged on the first part, the second electrode (3) and the third electrode (4) are longitudinally arranged on the second part at intervals, and the tail ends of the second electrode (3) and the third electrode (4) are positioned at the edge of the second part and far away from the first part;

the polyimide film (1) is folded in half so that the first portion and the second portion are laminated, and the third electrode (4) is connected to the first electrode (2) with ends of the second electrode (3) and the third electrode (4) exposed; -said PVDF film (5) is sandwiched between said first and second portions; one end, close to the diagonal line, of the first electrode (2) is arranged on one side, adjacent to the first part, of the PVDF film (5), one end, close to the diagonal line, of the second electrode (3) is arranged on one side, adjacent to the second part, of the PVDF film (5), and the area of one end, close to the diagonal line, of the first electrode (2) and the area of one end, close to the diagonal line, of the second electrode (3) are both smaller than the area of the PVDF film (5); the end of the third electrode (4) is connected to the first lead terminal, and the end of the second electrode (3) is connected to the second lead terminal.

2. The PVDF film based flexible vibration sensor as claimed in claim 1, wherein the polyimide film (1) is rectangular in shape; and/or the shape of the electrode is rectangular or L-shaped.

3. A PVDF film based flexible vibration sensor as in claim 1, wherein the electrodes are provided on the polyimide film (1) by means of electroplating.

4. The PVDF-based flexible vibration sensor as claimed in any one of claims 1-3, wherein the material of the electrode is Cu, Ag, Ni or Au.

5. A PVDF film based flexible vibration sensor as in any of claims 1-3, wherein the thickness of the electrodes is 10-30 μm.

6. A PVDF-based flexible vibration sensor as in any of claims 1-3, wherein said PVDF film (5) and said first (2) and second (3) electrodes are bonded using a quick-drying conductive silver adhesive.

7. A PVDF film based flexible vibration sensor as in any of claims 1-3, wherein the first lead end comprises a first pop rivet (6) and a first cold-pressed O-type terminal (7); the second lead end comprises a second hollow rivet (8) and a second O-shaped cold-pressed terminal (9).

8. A preparation method of a PVDF film-based flexible vibration sensor is characterized by comprising the following steps:

cutting the PVDF film, and corroding the edge of the cut PVDF film to remove residual fine metal wires on the edge;

arranging a first electrode (2) on a first part of a polyimide film (1), arranging a second electrode (3) and a third electrode (4) on a second part of the polyimide film (1) at intervals longitudinally, wherein the first part and the second part are connected with each other along a folding line, and the tail ends of the second electrode (3) and the third electrode (4) are arranged at the edge of the second part and far away from the first part;

coating quick-drying conductive silver adhesive on the electrodes, coating packaging glue on other areas, and placing the cut PVDF film on one end of the second electrode (3) close to the folding line; the area of one end of the second electrode (3) close to the folding line is smaller than that of the PVDF film;

folding the polyimide film (1) in half along a folding line to laminate the first part and the second part, connecting the third electrode (4) with the first electrode (2), and exposing the ends of the second electrode (3) and the third electrode (4), wherein one end of the first electrode (2) close to the folding line is arranged on one side of the PVDF film (5) adjacent to the first part, and the area of one end of the first electrode (2) close to the folding line is smaller than that of the PVDF film;

pressing the position of the PVDF film, discharging redundant glue in the device by using a scraper and bonding the quick-drying conductive silver adhesive;

a first lead terminal and a second lead terminal are used to be connected to the ends of the third electrode (4) and the second electrode (3), respectively.

9. The method of claim 1, wherein the etching is performed with dilute hydrochloric acid.

10. The method for preparing a PVDF-film based flexible vibration sensor as claimed in claim 1, wherein the step of connecting the first and second lead terminals to the ends of the third electrode (4) and the second electrode (3) respectively is as follows: and punching holes at the tail ends of the third electrode (4) and the second electrode (3) by using a hollow rivet, placing the O-shaped cold-pressed terminal on the hollow rivet after punching, and compacting the hollow rivet to enable the O-shaped cold-pressed terminal to be embedded into the hollow rivet.

Technical Field

The invention belongs to the technical field of sensing, and particularly relates to a flexible vibration sensor based on a PVDF film and a preparation method thereof.

Background

In recent years, the fields of expressways, railway construction, bridges, aerospace and the like are rapidly developed, and the safety of the facilities is concerned with not only economic development but also people safety and national safety. To ensure the safety of these facilities, health monitoring of these facilities is required. The traditional piezoelectric ceramic sensor has the defects of large volume, high hardness, incapability of bending and the like, and in the actual application process, the sensor usually needs to acquire signals on a specific irregular surface, so the application range has certain limitation. The flexible sensor has good flexibility and ductility, can be freely bent or even folded, has flexible and various structural forms, can be randomly arranged according to the requirements of measurement conditions, and can conveniently detect complex surfaces. PVDF (polyvinylidene fluoride) film is a polymer film with excellent piezoelectric performance, has higher thermal stability, fatigue resistance and radiation resistance, chemical stability 10 times higher than that of ceramic, and acoustic impedance (S is 2.7 multiplied by 106 Pa.s/m)³) The frequency response range can reach 10 near water and human muscle tissue^-5–10^-9Hz, has high application sensitivity, and therefore, has become the most potential polymer piezoelectric material. In summary, the invention provides a PVDF film-based flexible vibration sensor with high efficiency and small package size and a manufacturing method thereof based on the flexible piezoelectric sensor requirements.

Disclosure of Invention

The invention aims to solve the technical problem in the prior art and provides a flexible vibration sensor based on a PVDF film and a preparation method thereof.

In order to solve the above technical problem, an embodiment of the present invention provides a flexible vibration sensor based on a PVDF film, including a polyimide film, a first electrode, a second electrode, a third electrode, a PVDF film, a first lead terminal, and a second lead terminal;

the polyimide film comprises a first part and a second part which are connected with each other, the first electrode is arranged on the first part, the second electrode and a third electrode are longitudinally arranged on the second part at intervals, and the tail ends of the second electrode and the third electrode are positioned at the edge of the second part and far away from the first part;

the polyimide film is folded in half to laminate the first portion and the second portion, and the third electrode is connected to the first electrode with ends of the second electrode and the third electrode exposed; the PVDF film is clamped between the first part and the second part; one end of the first electrode close to the diagonal line is arranged on one side, adjacent to the first part, of the PVDF film, one end of the second electrode close to the diagonal line is arranged on one side, adjacent to the second part, of the PVDF film, and the area of one end of the first electrode close to the diagonal line and the area of one end of the second electrode close to the diagonal line are both smaller than the area of the PVDF film; the end of the third electrode is connected to the first lead terminal, and the end of the second electrode is connected to the second lead terminal.

On the basis of the technical scheme, the invention can be further improved as follows.

Further, the shape of the polyimide film is rectangular; and/or the shape of the electrode is rectangular or L-shaped.

Further, the polyimide film has the dimensions of 10-30cm in length, 4cm in width and 55 μm in thickness.

Furthermore, the electrodes are arranged on the polyimide film in an electroplating mode.

Further, the electrode is made of copper, silver, nickel or gold.

Further, the thickness of the electrode is 10-30 μm.

Further, the thickness of the electrode is 18 μm.

Furthermore, quick-dry conductive silver adhesive is adopted to bond the PVDF film with the first electrode and the second electrode.

Further, the first part and the second part of the polyimide film are bonded by using packaging glue.

Further, the packaging glue is YLG-PVC30 soft glue.

Further, the first lead end comprises a first hollow rivet and a first O-shaped cold-pressed terminal; the second lead end comprises a second hollow rivet and a second O-shaped cold-pressed terminal.

Further, the internal diameter of the hollow rivet is 2.5 mm.

Furthermore, the type of the O-shaped cold-pressed terminal is OT 0.5-3.

In order to solve the above technical problems, an embodiment of the present invention provides a method for manufacturing a PVDF film-based flexible vibration sensor, including the following steps:

cutting the PVDF film, and corroding the edge of the cut PVDF film to remove residual fine metal wires on the edge;

arranging a first electrode on a first part of a polyimide film, arranging a second electrode and a third electrode on a second part of the polyimide film at intervals longitudinally, wherein the first part and the second part are connected with each other along a folding line, and the tail ends of the second electrode and the third electrode are arranged at the edge of the second part and far away from the first part;

coating quick-drying conductive silver adhesive on the electrode, coating packaging glue on other areas, and placing the cut PVDF film on one end of the second electrode close to the folding line; the area of one end of the second electrode close to the folding line is smaller than that of the PVDF film;

folding the polyimide film in half along a folding line to laminate the first part and the second part, connecting the third electrode with the first electrode and exposing the ends of the second electrode and the third electrode, wherein one end of the first electrode close to the folding line is arranged on one side of the PVDF film adjacent to the first part, and the area of one end of the first electrode close to the folding line is smaller than that of the PVDF film;

pressing the position of the PVDF film, discharging redundant glue in the device by using a scraper and bonding the quick-drying conductive silver adhesive;

first and second lead terminals are used to be connected to the ends of the third and second electrodes, respectively.

Further, the etching is performed using dilute hydrochloric acid.

Further, the step of connecting the first lead terminal and the second lead terminal to the ends of the third electrode and the second electrode, respectively, specifically includes: and punching holes at the tail ends of the third electrode and the second electrode by using a hollow rivet, arranging the O-shaped cold pressing terminal on the hollow rivet after punching, compacting the hollow rivet, and embedding the O-shaped cold pressing terminal into the hollow rivet.

Further, the scraper is a ruler, a plastic scraper or a rubber scraper.

Further, the packaging glue is YLG-PVC30 soft glue.

The invention has the beneficial effects that: the sensor provided by the invention has good flexibility and ductility, can be freely bent or even folded, has flexible and various structural forms, can be randomly arranged according to the requirements of the surface conditions of the measured object, can conveniently detect the surface of the complex measured object, and can play an important role in the fields with irregular surfaces, such as biological medicine, bridges and the like. In addition, the preparation method of the PVDF-film-based flexible vibration sensor is applicable to flexible film size, can greatly shorten the time for packaging the film into a device, does not damage the PVDF film, is compatible with the existing production process, and has the advantages of convenient packaging operation, short packaging time consumption, small packaging size, sensitive reaction and the like.

Drawings

FIG. 1 is a schematic view of a structure for forming an electrode on a polyimide film;

FIG. 2 is a schematic diagram of a structure in which a PVDF film is placed on an electrode;

FIG. 3 is a cross-sectional view of a PVDF film based flexible vibration sensor in accordance with an embodiment of the present invention;

fig. 4 is a graph illustrating an actual effect test of a PVDF film-based flexible vibration sensor according to an embodiment of the present invention.

In the drawings, the components represented by the respective reference numerals are listed below:

1. polyimide film, 2, first electrode, 3, second electrode, 4, third electrode, 5, PVDF film, 6, first hollow rivet, 7, first O type cold pressing terminal, 8, second hollow rivet, 9, second O type cold pressing terminal.

Detailed Description

The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the invention.

As shown in fig. 1 to 3, a PVDF film-based flexible vibration sensor according to a first embodiment of the present invention includes a polyimide film 1, a first electrode 2, a second electrode 3, a third electrode 4, a PVDF film 5, a first lead terminal, and a second lead terminal;

the polyimide film 1 comprises a first part and a second part which are connected with each other, the first electrode 2 is arranged on the first part, the second electrode 3 and the third electrode 4 are longitudinally arranged on the second part at intervals, and the tail ends of the second electrode 3 and the third electrode 4 are positioned at the edge of the second part and far away from the first part;

the polyimide film 1 is folded in half so that the first portion and the second portion are laminated, and the third electrode 4 is connected to the first electrode 2, and ends of the second electrode 3 and the third electrode 4 are exposed; the PVDF film 5 is sandwiched between the first part and the second part; one end of the first electrode 2 close to the diagonal line is arranged on one side of the PVDF film 5 adjacent to the first part, one end of the second electrode 3 close to the diagonal line is arranged on one side of the PVDF film 5 adjacent to the second part, and the area of one end of the first electrode 2 close to the diagonal line and the area of one end of the second electrode 3 close to the diagonal line are both smaller than the area of the PVDF film 5; the end of the third electrode 4 is connected to the first lead terminal, and the end of the second electrode 3 is connected to the second lead terminal.

In the above embodiment, the first electrode and the third electrode are used to extract the charge signal on one side of the PVDF film 5, and the second electrode is used to extract the charge signal on the other side of the PVDF film 5.

The area of one end of the first electrode 2 close to the folding line and the area of one end of the second electrode 3 close to the folding line are both smaller than the area of the PVDF film 5, so that the first electrode and the second electrode are prevented from being in contact to cause short circuit.

Optionally, the shape of the polyimide film 1 is rectangular; and/or the shape of the electrode is rectangular or L-shaped.

Alternatively, the polyimide film 1 has a length of 10 to 30cm, a width of 4cm and a thickness of 55 μm.

Optionally, the electrode is disposed on the polyimide film 1 by electroplating.

Optionally, the material of the electrode is copper, silver, nickel or gold.

Optionally, the thickness of the electrode is 10-30 μm.

Optionally, the thickness of the electrode is 18 μm.

Optionally, quick-drying conductive silver adhesive is used to bond the PVDF film 5 with the first electrode 2 and the second electrode 3.

Optionally, the first and second portions of the polyimide film 1 are bonded with a potting glue.

Optionally, the packaging glue is YLG-PVC30 soft glue.

Optionally, the first lead end comprises a first pop rivet 6 and a first cold-pressed O-terminal 7; the second lead end comprises a second hollow rivet 8 and a second O-shaped cold-pressed terminal 9.

Optionally, the blind rivet has an internal diameter of 2.5 mm.

Optionally, the type of the O-shaped cold-pressed terminal is OT 0.5-3.

The preparation method of the flexible vibration sensor based on the PVDF film provided by the second embodiment of the invention comprises the following steps:

cutting the PVDF film, and corroding the edge of the cut PVDF film to remove residual fine metal wires on the edge;

arranging a first electrode 2 on a first part of a polyimide film 1, arranging a second electrode 3 and a third electrode 4 on a second part of the polyimide film 1 at intervals longitudinally, wherein the first part and the second part are connected with each other along a folding line, and the tail ends of the second electrode 3 and the third electrode 4 are arranged on the edge of the second part and far away from the first part, as shown in FIG. 1;

coating quick-drying conductive silver adhesive on the electrodes, coating packaging glue on other areas, and placing the cut PVDF film on one end of the second electrode 3 close to the folding line; the area of one end of the second electrode 3 close to the folding line is smaller than that of the PVDF film, as shown in FIG. 2;

folding the polyimide film 1 in half along a folding line to laminate the first part and the second part, connecting the third electrode 4 with the first electrode 2, and exposing the ends of the second electrode 3 and the third electrode 4, wherein one end of the first electrode 2 close to the folding line is arranged on one side of the PVDF film 5 adjacent to the first part, and the area of one end of the first electrode 2 close to the folding line is smaller than that of the PVDF film;

pressing the position of the PVDF film, discharging redundant glue in the device by using a scraper and bonding the quick-drying conductive silver adhesive;

a first lead terminal and a second lead terminal are connected to the ends of the third electrode 4 and the second electrode 3, respectively, as shown in fig. 3, and fig. 3 is a cross-sectional view of a packaged PVDF film-based flexible vibration sensor with the first portion removed.

In the above embodiment, the PVDF film may be cut by using a surgical blade, and the cutting area should be slightly larger than the area of the required PVDF film, so as to leave a margin for the subsequent edge etching treatment; pressing the position of the PVDF film by adopting a flat weight; the scraper is adopted to discharge the redundant glue in the device, so that the flexibility of the device can be improved; the device can be placed in the shade to bond the silver paste.

Optionally, the etching is performed with dilute hydrochloric acid.

In the above embodiment, a thin cotton swab can be used to dip dilute hydrochloric acid and lightly wipe the edge to perform corrosion, and the amount of the dilute hydrochloric acid and the length of the edge electrode treatment need to be paid attention to during the corrosion process, so as to prevent measurement errors caused by excessive corrosion.

Optionally, the step of connecting the first lead terminal and the second lead terminal to the ends of the third electrode 4 and the second electrode 3 respectively includes: and punching holes at the tail ends of the third electrode 4 and the second electrode 3 by using a hollow rivet, arranging the O-shaped cold pressing terminal on the hollow rivet after punching, and compacting the hollow rivet to enable the O-shaped cold pressing terminal to be embedded into the hollow rivet.

Optionally, the squeegee is a ruler, a plastic squeegee, or a rubber squeegee.

Optionally, the packaging glue is YLG-PVC30 soft glue.

Fig. 4 shows a test chart of the actual effect of the PVDF film-based flexible vibration sensor, which is provided by the present invention, and the specific test mode is as follows: an external lead of the oscilloscope is connected with a cold-pressed terminal of the sensor by using an alligator clip, the sensor is arranged on the surface of the steel pipe, a certain vibration source is given to the outside, the waveform shown in figure 4 can be captured, and the sensor packaged by the method is high in sensitivity.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.