CN114301328B - Super-elastic micro-nano energy collection and sensing integrated micro-system, manufacturing method and using method - Google Patents
Super-elastic micro-nano energy collection and sensing integrated micro-system, manufacturing method and using method Download PDFInfo
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- CN114301328B CN114301328B CN202210002684.3A CN202210002684A CN114301328B CN 114301328 B CN114301328 B CN 114301328B CN 202210002684 A CN202210002684 A CN 202210002684A CN 114301328 B CN114301328 B CN 114301328B
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Abstract
The invention discloses a super-elastic micro-nano energy collection and sensing integrated micro-system, a manufacturing method and a using method, wherein the micro-system comprises an elastic substrate, a flexible circuit board coil, a deformation body, a conductive permanent magnet and a packaging layer; the elastic substrate is positioned at the bottom of the deformation body, the packaging layer is positioned at the top of the deformation body, a first space for placing a coil of the flexible circuit board is arranged between the elastic substrate and the deformation body, and a second space for placing a conductive permanent magnet is arranged between the packaging layer and the deformation body; the flexible circuit board coil and the conductive permanent magnet are externally connected with power supply equipment, and/or the flexible circuit board coil is externally connected with excitation alternating current. The invention realizes a superelastic micro-system integrating micro-nano energy collection and sensing, the friction part and the electromagnetic part have good electrical property output, and simultaneously realizes an active electromagnetic motion sensing function based on an electromagnetic induction law and/or a passive inductive pressure sensing function based on an eddy current effect (a representation form of the electromagnetic induction effect).
Description
Technical Field
The invention relates to the field of wearable intelligent microsystems, in particular to a super-elastic micro-nano energy collection and sensing integrated microsystem, a manufacturing method and a using method.
Background
In recent years, wearable electronic devices have become an important component of the internet of things as an emerging electronic device, and penetrate into aspects of life of people, including business operations, national defense security, medical health, sports assistance, and the like. Along with the rapid development of the internet of things technology, the wearable electronic equipment has a multifunctional and intelligent integrated development trend, and higher requirements are provided for the characteristics of flexibility, adhesion and the like of the wearable electronic equipment.
Accordingly, many researchers have focused on developing flexible wearable intelligent microsystems, and desire to achieve integrated integration of energy harvesting+supply, sensing, driving, and other functions. Over the last decades, with continued effort and exploration by researchers, more and more flexible wearable multifunction electronic devices have been proposed. However, at present, the key and difficulty of implementing the flexible wearable intelligent micro system is how to integrate multiple flexible wearable single functional modules, which has single function and low integration level, so that further development and practical application of the wearable electronic devices and equipment are limited to a great extent.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a super-elastic micro-nano energy source acquisition and sensing integrated micro-system, a manufacturing method and a using method.
The aim of the invention is realized by the following technical scheme:
the invention provides a super-elastic micro-nano energy collection and sensing integrated micro-system, which comprises an elastic substrate, a flexible circuit board coil, a deformation body, a conductive permanent magnet and a packaging layer, wherein the elastic substrate is arranged on the flexible circuit board coil; the elastic substrate is positioned at the bottom of the deformation body, the packaging layer is positioned at the top of the deformation body, a first space for placing a coil of the flexible circuit board is arranged between the elastic substrate and the deformation body, and a second space for placing a conductive permanent magnet is arranged between the packaging layer and the deformation body; the flexible circuit board coil and the conductive permanent magnet are externally connected with power supply equipment, and/or the flexible circuit board coil is externally connected with excitation alternating current.
Further, a round hole is formed in the center of the coil of the flexible circuit board, and the elastic substrate is provided with a cylinder which is matched and fixed with the round hole.
Further, the flexible circuit board coil includes an insulating layer, a dielectric layer below the insulating layer, and a copper coil between the insulating layer and the dielectric layer, and between the dielectric layer and the dielectric layer.
Further, the power supply equipment is an LED display screen.
Further, the upper and lower parts of the deformation body are respectively provided with a patterning groove, wherein the upper layer grooves are mutually communicated upper rectangular-lower circular composite grooves, the lower circular grooves are used for fixedly placing circular conductive permanent magnets, and the upper rectangular grooves are used for placing packaging layers and packaging the circular conductive permanent magnets; the lower layer groove is another rectangular groove and is used for providing an air layer between the friction pair of the flexible circuit board coil and the lower surface of the deformation body.
In a second aspect of the present invention, a method for manufacturing a micro-nano super-elastic energy collection and sensing integrated micro-system, includes the following steps:
placing the flexible circuit board coil on the surface of a liquid elastic material, and drying the liquid elastic material to form an elastic substrate to complete the assembly of the elastic substrate and the flexible circuit board coil;
the method comprises the steps of adopting silicon rubber as an adhesive liquid, coating liquid silicon rubber on the edge of a deformation body, then placing the deformation body on an elastic substrate, and drying to complete the assembly of the elastic substrate, the coil of a flexible circuit board and the deformation body;
and fixing the conductive permanent magnet in a groove on the upper surface of the deformation body, and packaging the conductive permanent magnet by adopting liquid silicone rubber to form a packaging layer.
Further, the liquid elastic material is a liquid sendust/silicone rubber compound, namely, a sendust magnetic powder core and liquid silicone rubber are prepared through a blending method.
Further, the placing the flexible circuit board coil on the surface of the liquid elastic material includes:
the prepared liquid-state FeSiAl/silicone rubber compound is dripped into a groove of a 3D printing die, and then a coil of a flexible circuit board is lightly arranged on the surface of the liquid-state FeSiAl/silicone rubber compound;
the deformation body is a silicon rubber-air composite deformation body obtained by adopting liquid silicon rubber through reverse molding of an assembled composite 3D printing die.
Further, the deformation body is aligned with the center of the flexible circuit board coil, ensuring that the circular conductive permanent magnet is aligned with the center of the flexible circuit board coil.
According to a third aspect of the present invention, there is provided a method for using a micro-nano super-elastic energy collection and sensing integrated micro-system, including a micro-nano energy collection step and a sensing step, wherein the micro-nano energy collection step includes a friction electric energy collection sub-step and an electromagnetic electric energy collection sub-step, and the friction electric energy collection sub-step includes:
in the initial state, the lower surface of the deformation body and the surface of the coil of the flexible circuit board do not have net charges, and are in a balanced state;
when the external force presses the lower surface of the deformation body to be in close contact with the coil of the flexible circuit board, the lower surface of the deformation body and the surface of the coil of the flexible circuit board generate equal quantity of heterogeneous charges due to the friction electrification effect, and the charges can exist on the surface of the friction pair more stably;
once the external force is withdrawn to separate the lower surface of the deformation body from the coil of the flexible circuit board, negative charges carried on the lower surface of the deformation body can induce opposite positive charges on the conductive permanent magnet serving as the electrode due to the electrostatic induction effect, so that the charges can flow between the electrode and the ground;
when repeated external force presses to periodically contact and separate the lower surface of the deformation body and the coil of the flexible circuit board, the charges can generate reciprocating flow between the conductive permanent magnets serving as electrodes due to electrostatic induction, so that the biomechanical energy is converted into electric energy;
the electromagnetic electric energy source collection substep comprises the following steps:
based on Faraday electromagnetic induction law, when the conductive permanent magnet and the flexible circuit board coil are repeatedly pressed by external force to make the conductive permanent magnet and the flexible circuit board coil circularly and reciprocally approach or separate, the magnetic flux passing through the flexible circuit board coil can be continuously increased or reduced, so that periodic induction current is generated in a flexible circuit board coil loop;
the sensing step comprises an active electromagnetic sensing sub-step and/or a passive inductive sensing sub-step, the active electromagnetic sensing sub-step comprising:
based on the law of electromagnetic induction, the electric output of the electromagnetic part is related to the speed of magnetic flux change passing through the closed circuit, when the frequency of external mechanical input is changed, the relative motion of the conductive permanent magnet and the flexible circuit board coil is changed, and the magnetic flux change speed passing through the flexible circuit board coil is also changed, so that the electromagnetic output is changed;
the passive inductive sensing substep comprises:
the conductive permanent magnet is regarded as an induction conductive target, and the flexible circuit board coil is regarded as an induction coil;
when the flexible circuit board coil is excited by external alternating current, the flexible circuit board coil can generate an alternating magnetic field; based on the eddy current effect, eddy currents are induced on the conductive permanent magnet near the flexible circuit board coil, and the eddy currents generate a magnetic field in the opposite direction to the magnetic field of the flexible circuit board coil; the coupling effect of the two magnetic fields in opposite directions is influenced by the relative distance between the conductive permanent magnet and the coil of the flexible circuit board;
when the deformation body is deformed under the action of external mechanical input, the relative distance between the conductive permanent magnet and the flexible circuit board coil is changed, and the coupling effect between the two magnetic fields in opposite directions is also changed; and controlling the displacement of the induction target by changing the magnitude of the external force, and further quantitatively evaluating the induction response behavior of the flexible circuit board coil to the external force.
Further, the using method further comprises a power supply step, including: the energy acquired through the micro-nano energy acquisition step supplies power to the power supply equipment.
The beneficial effects of the invention are as follows:
(1) In an exemplary embodiment of the present invention, a superelastic microsystem integrating micro-nano energy collection and active electromagnetic sensing is implemented, that is, the microsystem proposed by the exemplary embodiment of the present invention has good electrical performance output (implementing simultaneous conversion from single mechanical input to triboelectric output and electromagnetic output) of both the friction part and the electromagnetic part, while the microsystem proposed by the exemplary embodiment of the present invention simultaneously implements electromagnetic motion sensing functions (active and/or passive) based on the law of electromagnetic induction.
(2) In yet another exemplary embodiment of the present invention, a circular hole is provided in the center of the flexible circuit board coil, and when the flexible circuit board coil is assembled with the elastic substrate, the circular hole is filled with a cylinder to increase the effective magnetic permeability of the coil, thereby increasing the electrical output of the electromagnetic portion.
(3) In another exemplary embodiment of the present invention, the flexible circuit board coil is externally connected with an exciting alternating current, including passive inductive sensing, and the working principle is that: when the closed induction coil is energized by Alternating Current (AC), the flexible circuit board coil generates an alternating magnetic field. Due to the eddy current effect, eddy currents will be induced on the conductive induction target near the flexible circuit board coil, and the eddy currents will generate a magnetic field in the opposite direction to the flexible circuit board coil magnetic field. The effective inductance of the flexible circuit board coil is thus a result of the coupling effect of the two magnetic fields in opposite directions. When the deformation body is deformed under the external mechanical input, the relative distance between the induction target and the flexible circuit board coil changes, and the coupling effect between the magnetic fields in two opposite directions also changes. Therefore, the displacement of the induction target can be controlled by changing the magnitude of external mechanical input (namely pressure), so that the inductance response behavior of the flexible circuit board coil to the pressure can be quantitatively estimated.
(4) In yet another exemplary embodiment of the present invention, a method for manufacturing the superelastic micro-nano energy collection and sensing integrated micro-system is disclosed.
(5) In yet another exemplary embodiment of the present invention, the use of a ferromagnetic elastomer-sendust/silicone rubber composite as the elastic substrate may increase the permeability of the flexible circuit board coil and increase the electrical output of the electromagnetic portion as compared to an insulating silicone rubber substrate alone.
(6) In yet another exemplary embodiment of the present invention, the elastic substrate, the fabrication of the deformation body, are all reverse molded by a composite 3D printing mold.
(7) In yet another exemplary embodiment of the present invention, a method of using the superelastic micro-nano energy harvesting and sensing integrated micro-system is disclosed.
Drawings
FIG. 1 is a schematic diagram of a micro-nano energy harvesting and sensing integrated micro-system according to an exemplary embodiment of the present invention;
FIG. 2 is a schematic diagram of the voltage output of the friction portion of the micro-nano energy harvesting and sensing integrated micro-system provided in an exemplary embodiment of the present invention;
FIG. 3 is a schematic diagram of the electromagnetic portion current output of the superelastic micro-nano energy harvesting and sensing integrated micro-system provided in an exemplary embodiment of the present invention;
FIG. 4 is a schematic diagram of current output of an active electromagnetic sensing function of a micro-nano super-elastic energy harvesting and sensing integrated micro-system provided in an exemplary embodiment of the invention;
FIG. 5 is a schematic diagram of a flexible circuit board coil of a micro-nano super elastic energy harvesting and sensing integrated micro-system according to an exemplary embodiment of the present invention;
FIG. 6 is a schematic diagram of the inductance of a passive electromagnetic sensing function of a superelastic micro-nano energy harvesting and sensing integrated micro-system provided in an exemplary embodiment of the present invention;
FIG. 7 is a composite 3D mold reverse schematic diagram of a variation of the superelastic micro-nano energy harvesting and sensing integrated micro-system provided in an exemplary embodiment of the present invention;
in the figure, 1-elastic substrate, 101-cylinder, 2-flexible circuit board coil, 201-round hole, 202-insulating layer, 203-dielectric layer, 204-copper coil, 3-shape variant, 4-conductive permanent magnet, 5-encapsulation layer.
Detailed Description
The following description of the embodiments of the present invention will be made apparent and fully understood from the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In the description of the present invention, it should be noted that directions or positional relationships indicated as being "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are directions or positional relationships described based on the drawings are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the apparatus or elements to be referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.
In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
The terminology used in the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. As used in this application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any or all possible combinations of one or more of the associated listed items.
It should be understood that although the terms first, second, third, etc. may be used herein to describe various information, these information should not be limited by these terms. These terms are only used to distinguish one type of information from another. For example, a first message may also be referred to as a second message, and similarly, a second message may also be referred to as a first message, without departing from the scope of the present application. The word "if" as used herein may be interpreted as "at … …" or "at … …" or "responsive to a determination", depending on the context. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In addition, the technical features of the different embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.
Referring to fig. 1, fig. 1 shows a superelastic micro-nano energy collection and sensing integrated micro-system provided in an exemplary embodiment of the present invention, which comprises an elastic substrate 1, a flexible circuit board coil 2, a deformation body 3, a conductive permanent magnet 4, and a packaging layer 5; the elastic substrate 1 is positioned at the bottom of the deformation body 3, the packaging layer 5 is positioned at the top of the deformation body 3, a first space for placing the coil 2 of the flexible circuit board is arranged between the elastic substrate 1 and the deformation body 3, and a second space for placing the conductive permanent magnet 4 is arranged between the packaging layer 5 and the deformation body 3; the flexible circuit board coil 2 and the conductive permanent magnet 4 are externally connected with power supply equipment, and/or the flexible circuit board coil 2 is externally connected with excitation alternating current.
Specifically, in this exemplary embodiment, the energy harvesting includes a friction portion and an electromagnetic portion, wherein:
(1) The friction part comprises a friction pair, namely a first friction layer-deformation body 3 lower surface and a second friction layer-flexible circuit board coil 2, wherein the material of the deformation body 3 lower surface can be silicon rubber, and the material of an insulating layer at the top of the flexible circuit board coil 2 can be polyimide; the conductive electrode is the conductive permanent magnet 4.
The friction part is a single-electrode nano friction generator, and can effectively convert mechanical energy input into electric energy output based on the coupling effect of friction electrification and electrostatic induction. The working process is as follows: in the initial state, the two friction materials, namely the lower surface of the deformation body 3 and the upper surface of the flexible circuit board coil 2, have no net charges and are in an equilibrium state. When the deformation body 3 is in close contact with the flexible circuit board coil 2, the surface of the two friction layers can generate equal amount of heterogeneous charges due to the friction electrification effect, and the charges can exist on the friction pair surface more stably. Once the lower surface of the deformation body 3 and the flexible circuit board coil 2 are separated, negative charges carried on the lower surface of the deformation body 3 induce opposite positive charges on the conductive permanent magnet 4 as an electrode due to electrostatic induction effect, thereby causing the charges to flow between the electrode and the ground. When the lower surface of the deformable body 3 and the flexible circuit board coil 2 are periodically contacted and separated, the charges can generate reciprocating flow between the electrodes due to electrostatic induction, so that the mechanical energy is converted into electric energy.
In one exemplary embodiment, the silicone rubber is an ECOFLEX series silicone rubber.
The ECOFLEX series silicone rubber is ultra-soft platinum silicone rubber, the liquid silicone rubber is prepared by mixing part A and part B liquid in proportion, the liquid silicone rubber can be naturally solidified at room temperature, the shrinkage rate is small, the viscosity is low, the fluidity is good, the high temperature resistance is excellent, and the temperature can reach 300-500 ℃. The cured silicone rubber is favored for excellent properties such as super flexibility, super ductility, high tensile strength, tear resistance, and a large number of times of mold turnover. (wherein, in a preferred exemplary embodiment, part A and part B are mixed in a mass ratio of 1:1 to form a liquid silicone rubber)
In one exemplary embodiment, the elastic substrate 1 is made of a magnetic powder core-sendust and an insulating polymer-silicone rubber mixed.
The Fe-Si-Al alloy magnetic powder core consists of three metal elements of 85% Fe, 9% Si and 6% Al and has relative magnetic conductivity as high as 16000-36000.
Compared with a single insulating silicon rubber substrate, the magnetic permeability of the flexible circuit board coil 2 can be improved by adopting the ferromagnetic elastomer-Fe-Si-Al/silicon rubber compound as the elastic substrate 1, and further, the electric output of the electromagnetic part can be improved.
(2) The electromagnetic part includes: the flexible circuit board coil 2 comprises a conductive permanent magnet 4, a flexible circuit board coil 2 and an elastic substrate 1.
The working principle of the electromagnetic part is as follows: based on faraday's law of electromagnetic induction, the induced current in a closed loop is proportional to the change in magnetic flux through the coil. When the conductive permanent magnet 4 and the flexible circuit board coil 2 perform periodic relative movement, periodic electric signal output (periodic induced current is generated in the loop of the flexible circuit board coil 2) is generated, and conversion from mechanical energy input to electric energy output is completed.
The friction part and the electromagnetic part can simultaneously generate friction electric output and electromagnetic output under the action of external force, so that the friction-electromagnetic composite micro-nano energy collection function is realized.
The friction part may generate an output voltage of about 240V under an external force of a frequency of 6Hz, as shown in fig. 2; the electromagnetic portion may produce an output current of about 3.3mA, as shown in fig. 3. Experiments prove that micro energy generated by the micro system can successfully drive some micro electronic devices, such as triboelectric output can be used for directly driving an LED display screen, an electromagnetic part can lighten the LED display screen with the help of an energy storage unit, and a friction-electromagnetic composite output can drive a low-power consumption calculator with the help of a power management circuit.
(3) Meanwhile, for the electromagnetic portion, the electromagnetic output thereof is correlated with the speed of change of the magnetic flux passing through the flexible circuit board coil 2. Therefore, according to the unique quantitative correlation between the electromagnetic output and the external excitation frequency, the active electromagnetic sensing function based on the electromagnetic induction effect can be realized.
The active electromagnetic sensing function of the superelastic microsystem proposed in the present exemplary embodiment benefits from the dependence of electromagnetic output on external mechanical frequencies. Based on the law of electromagnetic induction, the magnitude of the electrical output of the electromagnetic part is related to the speed of the magnetic flux passing through the closed circuit, when the frequency of the external mechanical input is changed, the relative motion of the conductive permanent magnet 4 and the flexible circuit board coil 2 is changed, and the change speed of the magnetic flux passing through the flexible circuit board coil 2 is also changed, so that the magnitude of the electromagnetic output is changed. Experiments have shown that the output current of the electromagnetic part increases almost linearly (0.5 mA to 6.5 mA) when the external force frequency increases gradually from 1Hz to 10Hz, as shown in fig. 4. It follows that the electromagnetic part can realize a good active electromagnetic sensing function based on a unique quantitative correlation between the electromagnetic output magnitude and the external mechanical input frequency.
(4) When the flexible circuit board coil 2 is externally connected with exciting alternating current:
specifically, in this exemplary embodiment, the superelastic micro-nano energy collection and sensing integrated micro-system proposed in an exemplary embodiment of the present invention includes a conductive permanent magnet 4 (induction conductor), a deformation body 3 (silicone rubber-air composite deformation body), a flexible circuit board coil 2 (induction coil); the structure provides feasibility for the micro system to realize the passive inductive sensing function based on the eddy current effect. The eddy currents are a manifestation of electromagnetic induction effects.
The working principle of the passive inductive sensing is as follows: when the closed induction coil is excited by Alternating Current (AC), the flexible circuit board coil 2 generates an alternating magnetic field. Due to the eddy current effect, eddy currents will be induced on the conductive induction target in the vicinity of the flexible circuit board coil 2, and the eddy currents will generate a magnetic field in the opposite direction to the magnetic field of the flexible circuit board coil 2. The effective inductance value of the flexible circuit board coil 2 is thus a result of the coupling effect of the two magnetic fields in opposite directions. When the deformation body 3 is deformed under the external mechanical input, the relative distance between the induction target and the flexible circuit board coil 2 is changed, and the coupling effect between the magnetic fields in two opposite directions is also changed. Therefore, by changing the magnitude of the external mechanical input (i.e. pressure), we can control the displacement of the induction target, and further quantitatively evaluate the inductive response behavior of the flexible circuit board coil 2 to the pressure, as shown in fig. 6. Based on the sensing behavior of the inductance value of the flexible circuit board coil to the external force, the micro system can realize the passive inductive sensing function based on the eddy current effect.
Therefore, in summary, the exemplary embodiment of the present invention realizes a superelastic micro-system integrating micro-nano energy collection and electromagnetic sensing (active and/or passive), that is, the micro-system proposed by the exemplary embodiment of the present invention has good electrical performance output (realizes simultaneous conversion from single mechanical input to triboelectric output and electromagnetic output) in both the friction part and the electromagnetic part, and simultaneously realizes both an active electromagnetic motion sensing function and a passive inductive pressure sensing function based on the law of electromagnetic induction.
More preferably, in an exemplary embodiment, the flexible circuit board coil 2 is provided with a circular hole 201 at the center, and the elastic base 1 is provided with a cylinder 101 that is matched and fixed with the circular hole 201.
Specifically, in this exemplary embodiment, the flexible circuit board coil 2 of the electromagnetic portion is obtained based on the flexible circuit technology, and a circular hole 201 is formed in the center of the flexible circuit board coil 2, and when the flexible circuit board coil 2 is assembled with the elastic substrate 1, the circular hole 201 is filled with the cylinder 101, so as to increase the effective magnetic permeability of the coil, and thus, the electrical output of the electromagnetic portion.
More preferably, in an exemplary embodiment, as shown in fig. 5, the flexible circuit board coil 2 includes an insulating layer 202, a dielectric layer 203, and a copper coil 204, the dielectric layer 203 being located below the insulating layer 202, the copper coil 204 being located between the insulating layer 202 and the dielectric layer 203, and between the dielectric layer 203 and the dielectric layer 203.
Wherein fig. 5 shows that the flexible circuit board coil 2 adopts a four-layer coil structure design, which comprises a dielectric layer 202, a copper coil 204, a dielectric layer 202, a copper coil 204 and an insulating layer 202 from below.
The flexible circuit originated in the 70 s of the last century and is a printed circuit with high reliability and excellent flexibility, and is widely focused and used by researchers due to its excellent characteristics of flexibility, bendability, light folding quality, convenience in installation and the like. In the structure of the flexible circuit, the constituent materials are mainly an insulating film material (most commonly, a polyester film or a polyimide film, wherein the polyimide film is used in an amount of approximately 80% by weight), a conductor (copper foil), and an adhesive. In one exemplary embodiment, polyimide is used as the substrate for both dielectric layer 202 and insulating layer 204.
The total thickness of the flexible circuit board coil 2 is 240 mu m; single layer coil (copper coil 204) has an inner diameter (D in ) 6.65mm, outer diameter (D out ) 20mm, 19 turns, 200 μm line width, 150 μm line spacing, 18 μm copper thickness.
More preferably, in an exemplary embodiment, the circular conductive permanent magnet 4 iron of the electromagnetic unit is a neodymium iron boron permanent magnet.
Wherein, the conductive permanent magnet 4 is a NdFeB permanent magnet, the diameter is 20mm, the thickness is 2mm, the surface resistance is about 0.35mΩ/sq, and the magnetic field strength is about 110.63mT.
More preferably, in an exemplary embodiment, as shown in fig. 1, the deformation body 3 is provided with patterned grooves at the upper and lower sides, wherein the upper layer groove is an upper rectangular-lower circular composite groove which is mutually communicated, the lower circular groove is used for fixedly placing the circular conductive permanent magnet 4, the upper rectangular groove is used for placing the encapsulation layer 5, and the circular conductive permanent magnet 4 is encapsulated; the lower rectangular groove is another rectangular groove, and is used for providing an air layer between the friction pair of the flexible circuit board coil 2 and the lower surface of the deformation body 3.
In still another exemplary embodiment of the present invention, a method for manufacturing a micro-nano super elastic energy collection and sensing integrated micro-system according to any one of the foregoing exemplary embodiments is provided, including the following steps:
s01: placing the flexible circuit board coil 2 on the surface of a liquid elastic material, and drying the liquid elastic material to form an elastic substrate 1, so as to complete the assembly of the elastic substrate 1 and the flexible circuit board coil 2;
s03: the method comprises the steps of adopting silicon rubber as an adhesive liquid, coating liquid silicon rubber on the edge of a deformation body 3, then placing the deformation body 3 on an elastic substrate 1, and drying to complete the assembly of the elastic substrate 1, a flexible circuit board coil 2 and the deformation body 3;
s05: the conductive permanent magnet 4 is fixed in a groove on the upper surface of the deformation body 3, and the conductive permanent magnet 4 is encapsulated by liquid silicone rubber, so that an encapsulation layer 5 is formed.
Specifically, in this exemplary embodiment, a manufacturing method of the super-elastic micro-nano energy collection and sensing integrated micro-system is disclosed.
More preferably, in an exemplary embodiment, the liquid elastic material is a liquid sendust/silicone rubber composite, i.e., a sendust powder core is blended with a liquid silicone rubber.
Specifically, in this exemplary embodiment, the use of a ferromagnetic elastomer-sendust/silicone rubber composite as the elastic substrate 1 can increase the permeability of the flexible circuit board coil 2 and increase the electrical output size of the electromagnetic portion, as compared to the insulating silicone rubber substrate alone. Wherein, in a preferred exemplary embodiment, the elastic substrate 1 is made by mixing and drying 3g of sendust core and 3g of liquid silicone rubber, and the sendust core has a diameter of 7 μm to 20 μm.
More preferably, in an exemplary embodiment, the placing the flexible circuit board coil on the surface of the liquid elastic material in the step S01 includes: the prepared liquid-state FeSiAl/silicone rubber compound is dripped into a groove of a 3D printing die, and then a flexible circuit board coil 2 is lightly arranged on the surface of the liquid-state FeSiAl/silicone rubber compound;
the deformation body 3 is a silicon rubber-air composite deformation body 3 obtained by adopting liquid silicon rubber through reverse molding of an assembled composite 3D printing die.
Thus, in this exemplary embodiment, the elastic substrate 1 and the deformation body 3 are manufactured by inverse molding with a composite 3D printing mold, wherein a schematic diagram of inverse molding with the composite 3D mold of the deformation body 3 is shown in fig. 7.
More preferably, in an exemplary embodiment, the deformation body 3 is aligned with the center of the flexible circuit board coil 2, ensuring that the circular conductive permanent magnet 4 is aligned with the center of the flexible circuit board coil 2.
In yet another exemplary embodiment of the present invention, a method for using the integrated micro-nano super elastic energy harvesting and sensing micro-system according to any one of the foregoing exemplary embodiments is provided, including a micro-nano energy harvesting step and a sensing step, the micro-nano energy harvesting step including a friction electric energy harvesting sub-step and an electromagnetic electric energy harvesting sub-step, the friction electric energy harvesting sub-step including:
in the initial state, the lower surface of the deformation body 3 and the surface of the flexible circuit board coil 2 are not provided with net charges, and are in an equilibrium state;
when the external force presses the lower surface of the deformation body 3 to be in close contact with the flexible circuit board coil 2, the lower surface of the deformation body 3 and the surface of the flexible circuit board coil 2 generate equal quantity of heterogeneous charges due to the friction electrification effect, and the charges can exist on the friction pair surface more stably;
once the external force is withdrawn to separate the lower surface of the deformation body 3 from the flexible circuit board coil 2, negative charges carried on the lower surface of the deformation body 3 induce opposite positive charges on the conductive permanent magnet 4 serving as an electrode due to the electrostatic induction effect, so that the charges flow between the electrode and the ground;
when repeated external force presses to periodically contact and separate the lower surface of the deformation body 3 and the flexible circuit board coil 2, the charges can generate reciprocating flow between the conductive permanent magnets 4 serving as electrodes due to electrostatic induction, so that the biomechanical energy is converted into electric energy;
the electromagnetic electric energy source collection substep comprises the following steps:
based on Faraday electromagnetic induction law, when the conductive permanent magnet 4 and the flexible circuit board coil 2 are repeatedly pressed by external force to make the conductive permanent magnet and the flexible circuit board coil 2 come close to or separate from each other in a cyclic and reciprocating manner, the magnetic flux passing through the flexible circuit board coil 2 can be continuously increased or reduced, so that periodic induction current is generated in the loop of the flexible circuit board coil 2;
comprising an active electromagnetic sensing sub-step and/or a passive inductive sensing sub-step, the active electromagnetic sensing sub-step comprising:
based on the law of electromagnetic induction, the magnitude of the electrical output of the electromagnetic part is related to the speed of the magnetic flux passing through the closed circuit, when the frequency of the external mechanical input is changed, the relative motion of the conductive permanent magnet 4 and the flexible circuit board coil 2 is changed, and the change speed of the magnetic flux passing through the flexible circuit board coil 2 is also changed, so that the magnitude of the electromagnetic output is changed.
The passive inductive sensing substep comprises:
the conductive permanent magnet 4 is regarded as an induction conductive target, and the flexible circuit board coil 2 is regarded as an induction coil;
when the flexible circuit board coil 2 is excited by external alternating current, the flexible circuit board coil 2 generates an alternating magnetic field; based on the eddy current effect, eddy currents are induced on the conductive permanent magnet 4 near the flexible circuit board coil 2, and the eddy currents generate a magnetic field in the opposite direction to the magnetic field of the flexible circuit board coil 2; the coupling effect of the two magnetic fields in opposite directions is influenced by the relative distance between the conductive permanent magnet 4 and the flexible circuit board coil 2;
when the deformation body is deformed under the action of external mechanical input, the relative distance between the conductive permanent magnet 4 and the flexible circuit board coil 2 is changed, and the coupling effect between the magnetic fields in two opposite directions is also changed; the displacement of the induction target is controlled by changing the magnitude of the external force, so that the inductance response behavior of the flexible circuit board coil 2 to the external force is quantitatively evaluated.
More preferably, in an exemplary embodiment, the using method further includes a power supplying step, including: the energy acquired through the micro-nano energy acquisition step supplies power to the power supply equipment.
In yet another exemplary embodiment of the present invention, a wearable electronic device is provided, the wearable electronic device including a superelastic micro-nano energy collection and sensing integrated micro-system, the system including an elastic substrate 1, a flexible circuit board coil 2, a deformation body 3, a conductive permanent magnet 4, and an encapsulation layer 5; the elastic substrate 1 is positioned at the bottom of the deformation body 3, the packaging layer 5 is positioned at the top of the deformation body 3, a first space for placing the coil 2 of the flexible circuit board is arranged between the elastic substrate 1 and the deformation body 3, and a second space for placing the conductive permanent magnet 4 is arranged between the packaging layer 5 and the deformation body 3; the flexible circuit board coil 2 and the conductive permanent magnet 4 are externally connected with power supply equipment, and/or the flexible circuit board coil 2 is externally connected with excitation alternating current.
More preferably, in an exemplary embodiment, the flexible circuit board coil 2 is provided with a circular hole 201 at the center, and the elastic base 1 is provided with a cylinder 101 that is matched and fixed with the circular hole 201.
More preferably, in an exemplary embodiment, the flexible circuit board coil 2 includes an insulating layer 202, a dielectric layer 203, and a copper coil 204, the dielectric layer 203 being located below the insulating layer 202, and the copper coil 204 being located between the insulating layer 202 and the dielectric layer 203, and between the dielectric layer 203 and the dielectric layer 203.
More preferably, in an exemplary embodiment, the power supply device is an LED display screen.
More preferably, in an exemplary embodiment, the deformation body 3 is provided with patterned grooves at the upper and lower sides, wherein the upper layer groove is an upper rectangular-lower circular composite groove which is mutually communicated, the lower circular groove is used for fixedly placing the circular conductive permanent magnet 4, the upper rectangular groove is used for placing the packaging layer 5, and the circular conductive permanent magnet 4 is packaged; the lower rectangular groove is another rectangular groove, and is used for providing an air layer between the friction pair of the flexible circuit board coil 2 and the lower surface of the deformation body 3.
More preferably, in an exemplary embodiment, the material of the lower surface of the deformation body 3 is silicone rubber, and the material of the insulating layer 202 on top of the flexible circuit board coil 2 is polyimide.
More preferably, in an exemplary embodiment, the elastic substrate 1 is made of a magnetic powder core-sendust and an insulating polymer-silicone rubber blend.
More preferably, in an exemplary embodiment, the triboelectric output (the friction part comprises a friction pair, namely the lower surface of the first friction layer-deformation body 3 and the second friction layer-flexible circuit board coil 2, wherein the lower surface material of the deformation body 3 can be silicon rubber, the insulating layer material on the top of the flexible circuit board coil 2 can be polyimide, the conductive electrode, namely the conductive permanent magnet 4) can be used for directly driving the LED display screen, the electromagnetic part (the electromagnetic part comprises the conductive permanent magnet 4, the flexible circuit board coil 2 and the elastic substrate 1) can lighten the LED display screen with the help of an energy storage unit, and the friction-electromagnetic composite output can drive the low-power consumption calculator with the help of a power management circuit.
More preferably, in an exemplary embodiment, the circular conductive permanent magnets 4 of the electromagnetic unit are neodymium-iron-boron permanent magnets.
The principle is the same as that of the foregoing exemplary embodiment, and a detailed description is omitted herein.
It is apparent that the above examples are given by way of illustration only and not by way of limitation, and that other variations or modifications may be made in the various forms based on the above description by those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. And obvious variations or modifications thereof are contemplated as falling within the scope of the present invention.
Claims (13)
1. A manufacturing method of a super-elastic micro-nano energy collection and sensing integrated micro-system is characterized by comprising the following steps of: the system comprises an elastic substrate, a flexible circuit board coil, a deformation body, a conductive permanent magnet and a packaging layer; the elastic substrate is positioned at the bottom of the deformation body, the packaging layer is positioned at the top of the deformation body, a first space for placing a coil of the flexible circuit board is arranged between the elastic substrate and the deformation body, and a second space for placing a conductive permanent magnet is arranged between the packaging layer and the deformation body; the flexible circuit board coil and the conductive permanent magnet are externally connected with power supply equipment, and/or the flexible circuit board coil is externally connected with excitation alternating current;
the manufacturing method comprises the following steps:
placing the flexible circuit board coil on the surface of a liquid elastic material, and drying the liquid elastic material to form an elastic substrate to complete the assembly of the elastic substrate and the flexible circuit board coil;
the method comprises the steps of adopting silicon rubber as an adhesive liquid, coating liquid silicon rubber on the edge of a deformation body, then placing the deformation body on an elastic substrate, and drying to complete the assembly of the elastic substrate, the coil of a flexible circuit board and the deformation body;
and fixing the conductive permanent magnet in a groove on the upper surface of the deformation body, and packaging the conductive permanent magnet by adopting liquid silicone rubber to form a packaging layer.
2. The method for manufacturing the super-elastic micro-nano energy collection and sensing integrated micro-system according to claim 1, which is characterized in that: the flexible circuit board coil center is equipped with the round hole, the elastic substrate be provided with the round hole match fixed cylinder.
3. The method for manufacturing the super-elastic micro-nano energy collection and sensing integrated micro-system according to claim 1, which is characterized in that: the flexible circuit board coil includes an insulating layer, a dielectric layer below the insulating layer, and a copper coil between the insulating layer and the dielectric layer, and between the dielectric layer and the dielectric layer.
4. The method for manufacturing the super-elastic micro-nano energy collection and sensing integrated micro-system according to claim 1, which is characterized in that: the power supply equipment is an LED display screen.
5. The method for manufacturing the super-elastic micro-nano energy collection and sensing integrated micro-system according to claim 1, which is characterized in that: the upper and lower parts of the deformation body are respectively provided with a patterning groove, wherein the upper layer grooves are upper rectangular-lower circular composite grooves which are communicated with each other, the lower circular grooves are used for fixedly placing circular conductive permanent magnets, the upper rectangular grooves are used for placing packaging layers, and the circular conductive permanent magnets are packaged; the lower layer groove is another rectangular groove and is used for providing an air layer between the friction pair of the flexible circuit board coil and the lower surface of the deformation body.
6. The manufacturing method according to any one of claims 1 to 5, characterized in that: the liquid elastic material is a liquid sendust/silicone rubber compound, namely, a sendust magnetic powder core and liquid silicone rubber are prepared by a blending method.
7. The method of manufacturing according to claim 6, wherein: the placing of the flexible circuit board coil on the surface of the liquid elastic material comprises:
the prepared liquid-state FeSiAl/silicone rubber compound is dripped into a groove of a 3D printing die, and then a coil of a flexible circuit board is lightly arranged on the surface of the liquid-state FeSiAl/silicone rubber compound;
the deformation body is a silicon rubber-air composite deformation body obtained by adopting liquid silicon rubber through reverse molding of an assembled composite 3D printing die.
8. The application method of the super-elastic micro-nano energy collection and sensing integrated micro-system is characterized by comprising the following steps of: the system comprises an elastic substrate, a flexible circuit board coil, a deformation body, a conductive permanent magnet and a packaging layer; the elastic substrate is positioned at the bottom of the deformation body, the packaging layer is positioned at the top of the deformation body, a first space for placing a coil of the flexible circuit board is arranged between the elastic substrate and the deformation body, and a second space for placing a conductive permanent magnet is arranged between the packaging layer and the deformation body; the flexible circuit board coil and the conductive permanent magnet are externally connected with power supply equipment, and/or the flexible circuit board coil is externally connected with excitation alternating current;
the using method comprises a micro-nano energy source acquisition step and a sensing step, wherein the micro-nano energy source acquisition step comprises a friction electric energy source acquisition sub-step and an electromagnetic electric energy source acquisition sub-step, and the friction electric energy source acquisition sub-step comprises the following steps:
in the initial state, the lower surface of the deformation body and the surface of the coil of the flexible circuit board do not have net charges, and are in a balanced state;
when the external force presses the lower surface of the deformation body to be in close contact with the coil of the flexible circuit board, the lower surface of the deformation body and the surface of the coil of the flexible circuit board generate equal quantity of heterogeneous charges due to the friction electrification effect, and the charges can exist on the surface of the friction pair more stably;
once the external force is withdrawn to separate the lower surface of the deformation body from the coil of the flexible circuit board, negative charges carried on the lower surface of the deformation body can induce opposite positive charges on the conductive permanent magnet serving as the electrode due to the electrostatic induction effect, so that the charges can flow between the electrode and the ground;
when repeated external force presses to periodically contact and separate the lower surface of the deformation body and the coil of the flexible circuit board, the charges can generate reciprocating flow between the conductive permanent magnets serving as electrodes due to electrostatic induction, so that the biomechanical energy is converted into electric energy;
the electromagnetic electric energy source collection substep comprises the following steps:
based on Faraday electromagnetic induction law, when the conductive permanent magnet and the flexible circuit board coil are repeatedly pressed by external force to make the conductive permanent magnet and the flexible circuit board coil circularly and reciprocally approach or separate, the magnetic flux passing through the flexible circuit board coil can be continuously increased or reduced, so that periodic induction current is generated in a flexible circuit board coil loop;
the sensing step comprises an active electromagnetic sensing sub-step and/or a passive inductive sensing sub-step, the active electromagnetic sensing sub-step comprising:
based on the law of electromagnetic induction, the electric output of the electromagnetic part is related to the speed of magnetic flux change passing through the closed circuit, when the frequency of external mechanical input is changed, the relative motion of the conductive permanent magnet and the flexible circuit board coil is changed, and the magnetic flux change speed passing through the flexible circuit board coil is also changed, so that the electromagnetic output is changed;
the passive inductive sensing substep comprises:
the conductive permanent magnet is regarded as an induction conductive target, and the flexible circuit board coil is regarded as an induction coil;
when the flexible circuit board coil is excited by external alternating current, the flexible circuit board coil can generate an alternating magnetic field; based on the eddy current effect, eddy currents are induced on the conductive permanent magnet near the flexible circuit board coil, and the eddy currents generate a magnetic field in the opposite direction to the magnetic field of the flexible circuit board coil; the coupling effect of the two magnetic fields in opposite directions is influenced by the relative distance between the conductive permanent magnet and the coil of the flexible circuit board;
when the deformation body is deformed under the action of external mechanical input, the relative distance between the conductive permanent magnet and the flexible circuit board coil is changed, and the coupling effect between the two magnetic fields in opposite directions is also changed; and controlling the displacement of the induction target by changing the magnitude of the external force, and further quantitatively evaluating the induction response behavior of the flexible circuit board coil to the external force.
9. The method for using the super-elastic micro-nano energy collection and sensing integrated micro-system according to claim 8, which is characterized in that: the flexible circuit board coil center is equipped with the round hole, the elastic substrate be provided with the round hole match fixed cylinder.
10. The method for using the super-elastic micro-nano energy collection and sensing integrated micro-system according to claim 8, which is characterized in that: the flexible circuit board coil includes an insulating layer, a dielectric layer below the insulating layer, and a copper coil between the insulating layer and the dielectric layer, and between the dielectric layer and the dielectric layer.
11. The method for using the super-elastic micro-nano energy collection and sensing integrated micro-system according to claim 8, which is characterized in that: the power supply equipment is an LED display screen.
12. The method for using the super-elastic micro-nano energy collection and sensing integrated micro-system according to claim 8, which is characterized in that: the upper and lower parts of the deformation body are respectively provided with a patterning groove, wherein the upper layer grooves are upper rectangular-lower circular composite grooves which are communicated with each other, the lower circular grooves are used for fixedly placing circular conductive permanent magnets, the upper rectangular grooves are used for placing packaging layers, and the circular conductive permanent magnets are packaged; the lower layer groove is another rectangular groove and is used for providing an air layer between the friction pair of the flexible circuit board coil and the lower surface of the deformation body.
13. The use according to any one of claims 8 to 12, characterized in that: the use method further comprises a power supply step, comprising: the energy acquired through the micro-nano energy acquisition step supplies power to the power supply equipment.
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| CN105846641A (en) * | 2016-04-19 | 2016-08-10 | 中北大学 | Magnet suspension-type vibration driving electromagnetic energy harvester |
| CN109889009A (en) * | 2019-03-21 | 2019-06-14 | 中山大学 | A kind of electromagnetism based on magnetic acicular texture-friction combined generator |
| CN111726026A (en) * | 2019-03-20 | 2020-09-29 | 深圳市柔纬联科技有限公司 | Combined type energy collector and wearable electronic equipment |
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| US9790928B2 (en) * | 2012-09-21 | 2017-10-17 | Georgia Tech Research Corporation | Triboelectric generators and sensors |
| US10932063B2 (en) * | 2018-05-29 | 2021-02-23 | Georgia Tech Research Corporation | Thin and flexible self-powered vibration transducer employing triboelectric nanogeneration |
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| CN105846641A (en) * | 2016-04-19 | 2016-08-10 | 中北大学 | Magnet suspension-type vibration driving electromagnetic energy harvester |
| CN111726026A (en) * | 2019-03-20 | 2020-09-29 | 深圳市柔纬联科技有限公司 | Combined type energy collector and wearable electronic equipment |
| CN109889009A (en) * | 2019-03-21 | 2019-06-14 | 中山大学 | A kind of electromagnetism based on magnetic acicular texture-friction combined generator |
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