Liquid interaction driven self-powered wireless sensor and preparation method thereof

Abstract

The invention relates to the technical field of wireless sensors, and discloses a liquid interaction driven self-powered wireless sensor and a preparation method thereof. The liquid interaction driven self-powered wireless sensor comprises an upper electrode, an electrification material film and an electromagnetic coil, the electrification material film is attached to the electromagnetic coil, the upper electrode is attached to the electrification material film, the upper electrode is connected with one end of the electromagnetic coil, and a capacitor is formed between the upper electrode and the other end of the electromagnetic coil. The capacitor and the electromagnetic coil form an oscillation circuit; when water drops drop on the electrification material film, the water drops and the electrification material film generate electricity through friction, so that when the water drops slide and pass through the upper electrode, a capacitor formed between the upper electrode and the electromagnetic coil is charged, an oscillation circuit formed by the capacitor and the electromagnetic coil generates an oscillation signal, and a decay magnetic field is generated around the electromagnetic coil due to the oscillation signal; and the electromagnetic coil wirelessly transmits an oscillation signal through the decay magnetic field, so that self-powered real-time transmission of the wireless sensor is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless sensors, and in particular to a liquid interactively driven self-powered wireless sensor and a preparation method thereof. Background Art

[0002] Wireless sensors have great application potential in the Internet of Things, covering smart homes, industrial Internet of Things, smart cities, medical health and other fields. They realize automated management and optimized decision-making through real-time monitoring and data transmission, improve efficiency, reduce costs, and enhance the intelligence and connectivity of the system.

[0003] Current wireless sensing solutions usually use liquid-solid friction nanogenerators to provide signals for wireless communication functional circuits, but this non-instantaneous self-powered wireless sensing solution cannot achieve real-time wireless communication without power supply. Another solution is to use liquid-solid friction nanogenerators to power the power storage unit in the wireless communication circuit, and wireless communication can be achieved after the power storage unit reaches the power requirement of the wireless communication circuit. However, this solution has problems such as signal delay and poor communication stability, and its performance in practical applications is challenging.

[0004] Therefore, the power generation performance of the current liquid-solid friction nanogenerator is far from sufficient to ensure the continuous communication of traditional wireless communication circuits, and cannot achieve self-powered real-time transmission, which greatly limits the application of wireless sensing solutions powered by liquid-solid friction nanogenerators. Summary of the invention

[0005] The purpose of the present invention is to provide a liquid interactively driven self-powered wireless sensor and a preparation method thereof, which can realize self-powered real-time transmission.

[0006] In order to solve the above technical problems, an embodiment of the present invention provides a liquid interactively driven self-powered wireless sensor, comprising: an upper electrode, an electrifying material film and an electromagnetic coil, wherein the electrifying material film is attached to the electromagnetic coil, the upper electrode is attached to the electrifying material film, and the upper electrode is connected to one end of the electromagnetic coil, so that a capacitor is formed between the upper electrode and the other end of the electromagnetic coil, and the capacitor and the electromagnetic coil form an oscillation circuit;

[0007] When water droplets fall on the electrifying material film, the water droplets and the electrifying material film generate electricity through friction. When the water droplets slide over the upper electrode, the capacitor formed between the upper electrode and the electromagnetic coil is charged, so that the oscillation circuit composed of the capacitor and the electromagnetic coil generates an oscillation signal. A decay magnetic field is generated around the electromagnetic coil due to the oscillation signal, and the electromagnetic coil wirelessly transmits the oscillation signal through the decay magnetic field to achieve wireless transmission.

[0008] Optionally, the upper electrode is a metal strip made of a conductive material such as copper, platinum, gold or silver, or a metal wire made of a conductive material such as copper, platinum, gold or silver.

[0009] Optionally, the electrifying material film is prepared from a composite material consisting of polytetrafluoroethylene, polyvinylidene fluoride, polyethylene terephthalate, polyvinyl chloride or fluoropolymer.

[0010] Optionally, the diameter of the electromagnetic coil is 0.01 to 200 mm, and the inductance value is 0.01 uH to 100 mH.

[0011] Optionally, the capacitance between the upper electrode and the electromagnetic coil is 0.01 pF to 100 uF.

[0012] Optionally, the decay magnetic field generated around the upper electrode and the electromagnetic coil is 500kHz to 15MHz.

[0013] Optionally, the electromagnetic coil is placed on a printed circuit board PCB or a flexible printed circuit board FPC.

[0014] An embodiment of the present invention further provides a method for preparing a liquid interactively driven self-powered wireless sensor, comprising:

[0015] A film of electrifying material is attached to the electromagnetic coil;

[0016] An upper electrode is attached to the electrifying material film, and the upper electrode is connected to one end of the electromagnetic coil, so that a capacitor is formed between the upper electrode and the electromagnetic coil, and the capacitor and the electromagnetic coil form an oscillating circuit;

[0017] Among them, when water droplets fall on the electrifying material film, the water droplets and the electrifying material film generate electricity through friction, so that when the water droplets slide over the upper electrode, the capacitor formed between the upper electrode and the electromagnetic coil is charged, so that the oscillation circuit composed of the capacitor and the electromagnetic coil generates an oscillation signal, and a decay magnetic field is generated around the electromagnetic coil due to the oscillation signal. The electromagnetic coil wirelessly transmits the oscillation signal through the decay magnetic field to realize wireless transmission.

[0018] The liquid interactively driven self-powered wireless sensor provided by the present invention has at least the following beneficial effects:

[0019] The present invention attaches an electrifying material film to the electromagnetic coil, and an upper electrode to the electrifying material film, which is equivalent to improving the lower electrode of the traditional liquid-solid friction nano-power generation device, giving the lower electrode an inductance characteristic, and the upper electrode is connected to one end of the electromagnetic coil, so that a capacitor is formed between the upper electrode and the other end of the electromagnetic coil, and then the capacitor and the electromagnetic coil form an oscillation circuit. At this time, when water drops fall on the electrifying material film, the water droplets and the electrifying material film generate electricity by friction, so that when the water droplets slide over the upper electrode, the capacitor formed between the upper electrode and the electromagnetic coil is charged, so that the oscillation circuit composed of the capacitor and the electromagnetic coil generates an oscillation signal, and a decay magnetic field is generated around the electromagnetic coil due to the oscillation signal. The electromagnetic coil wirelessly transmits the oscillation signal through the decay magnetic field to achieve wireless transmission.

[0020] Therefore, the wireless sensor of the present invention completes the liquid-solid contact power generation driven wireless transmission only through a three-layer structure (upper electrode, electrification material film and electromagnetic coil), wherein the electromagnetic coil is equivalent to the lower electrode of the traditional liquid-solid friction nanogenerator, and is therefore equivalent to constructing a liquid-solid friction nanogenerator based on a transistor discharge structure, and optimizing the transistor drain as a spiral electromagnetic coil. The liquid-solid friction nanogenerator of this structure generates a changing magnetic field (i.e., a decaying magnetic field) that can be used for communication in space through the instantaneous charge and discharge capacitor formed between the upper electrode and the electromagnetic coil, breaking through the scheme of powering the circuit after friction electrification and power storage, greatly simplifying the wireless transmission scheme, and solving the problem that the amount of electricity generated by the friction nanogenerator in the traditional scheme is far lower than the demand for starting the wireless transmission circuit, so that the liquid-solid friction nanogenerator is difficult to complete wireless transmission.

[0021] In addition, the wireless sensor has a simple structure and requires low self-power consumption, and is expected to be deployed over a large area to form a sensor network node for the liquid environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] One or more embodiments are exemplarily described by the pictures in the corresponding drawings, and these exemplary descriptions do not constitute limitations on the embodiments.

[0023] Figure 1 is a schematic structural diagram of a liquid interactively driven self-powered wireless sensor provided according to an embodiment of the present invention;

[0024] Figure 2 is a schematic diagram of the working mechanism of a liquid interactively driven self-powered wireless sensor provided according to an embodiment of the present invention;

[0025] Figure 3 The present invention is a flow chart of a method for preparing a liquid interactively driven self-powered wireless sensor according to an embodiment of the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. However, it will be appreciated by those skilled in the art that in the embodiments of the present invention, many technical details are proposed in order to enable the reader to better understand the present invention. However, even without these technical details and various changes and modifications based on the following embodiments, the technical scheme claimed in the present invention can be implemented. The division of the following embodiments is for the convenience of description and should not constitute any limitation on the specific implementation of the present invention. The various embodiments can be combined and referenced with each other without contradiction.

[0027] One embodiment of the present invention relates to a liquid interactively driven self-powered wireless sensor. The implementation details of the liquid interactively driven self-powered wireless sensor of this embodiment are described in detail below. The following content is only provided for the convenience of understanding the implementation details and is not necessary for the implementation of this solution.

[0028] The liquid interaction driven self-powered wireless sensor of this embodiment is as follows Figure 1 As shown, it consists of a three-layer structure, which includes, from top to bottom, an upper electrode 1, an electrifying material film 2 and an electromagnetic coil 3, wherein the electrifying material film 2 is attached to the electromagnetic coil 3, the upper electrode 1 is attached to the electrifying material film 2, and the upper electrode 1 is connected to one end of the electromagnetic coil 3, so that a capacitor is formed between the upper electrode 1 and the other end of the electromagnetic coil 3, and the capacitor and the electromagnetic coil 3 form an oscillation circuit.

[0029] Figure 2 The working mechanism of the liquid interactively driven self-powered wireless sensor of this embodiment is shown: when a water drop 4 falls on the electrifying material film 2, the water drop 4 and the electrifying material film 2 generate electricity by friction, so that when the water drop 4 slides over the upper electrode 1, the capacitor formed between the upper electrode 1 and the electromagnetic coil 3 is charged, so that the oscillation circuit composed of the capacitor and the electromagnetic coil 3 generates an oscillation signal, and a decay magnetic field is generated around the electromagnetic coil 3 due to the oscillation signal, so the electromagnetic coil 3 can wirelessly transmit the oscillation signal through the decay magnetic field to achieve wireless transmission. Attaching the electrifying material film 2 to the electromagnetic coil 3 can ensure that the electromagnetic coil 2 will not cause the water drop to short-circuit when the water drop rubs against the electrifying material film 2.

[0030] Among them, the preparation materials of the upper electrode 1 include but are not limited to: copper sheets, copper wires, and the types used are high-performance conductive materials, and are prepared into metal strips or metal wires through any of the above-mentioned high-performance conductive materials (such as copper, platinum, gold or silver), and finally the capacitance value between the upper electrode 1 and the other end of the electromagnetic coil 3 is 0.01pF~100uF.

[0031] The electrifying material film 2 is made of a composite material composed of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyethylene terephthalate (PET), polyvinyl chloride (PVC) or fluoropolymer, and the type used is a friction electrifying material.

[0032] The dimensions of the electromagnetic coil 3 are: outer diameter: 0.01-200 mm, inner diameter: 0-outer diameter, and the inductance value of the electromagnetic coil 3 is 0.01 uH-100 mH.

[0033] The decay magnetic field generated around the upper electrode 1 and the electromagnetic coil 3 is 500kHz to 15MHz.

[0034] In one example, the electromagnetic coil 3 is placed on a printed circuit board (PCB) or a flexible printed circuit board (FPC).

[0035] In this embodiment, the electrifying material film is attached to the electromagnetic coil, and the upper electrode is attached to the electrifying material film, which is equivalent to improving the lower electrode of the traditional liquid-solid friction nano-power generation device, giving the lower electrode an inductance characteristic, and the upper electrode is connected to one end of the electromagnetic coil, and a capacitor is formed between the upper electrode and the other end of the electromagnetic coil, so that the capacitor and the electromagnetic coil form an oscillation circuit. At this time, when water drops fall on the electrifying material film, the water droplets and the electrifying material film generate electricity by friction, so that when the water droplets slide over the upper electrode, the capacitor formed between the upper electrode and the electromagnetic coil is charged, so that the oscillation circuit composed of the capacitor and the electromagnetic coil generates an oscillation signal, and the electromagnetic coil generates a decay magnetic field due to the oscillation signal around the electromagnetic coil, and the electromagnetic coil wirelessly transmits the oscillation signal through the decay magnetic field to achieve wireless transmission.

[0036] Therefore, the wireless sensor completes the liquid-solid contact power generation driven wireless transmission through only three layers of structure (upper electrode, electrifying material film and electromagnetic coil), among which the electromagnetic coil is equivalent to the lower electrode of the traditional liquid-solid friction nanogenerator, so it is equivalent to constructing a liquid-solid friction nanogenerator based on the transistor discharge structure, and optimizing the transistor drain into a spiral electromagnetic coil. The liquid-solid friction nanogenerator of this structure generates a changing magnetic field (i.e., decaying magnetic field) that can be used for communication in space through the instantaneous charge and discharge capacitor formed between the upper electrode and the electromagnetic coil, breaking through the scheme of powering the circuit after friction electrification and power storage, greatly simplifying the wireless transmission scheme, and solving the problem that the power generated by the friction nanogenerator in the traditional scheme is far lower than the demand for starting the wireless transmission circuit, so that the liquid-solid friction nanogenerator is difficult to complete wireless transmission.

[0037] In addition, the wireless sensor has a simple structure and requires low self-power consumption, and is expected to be deployed over a large area to form a sensor network node for the liquid environment.

[0038] Another embodiment of the present invention relates to a method for preparing a liquid interactively driven self-powered wireless sensor. The implementation details of the method for preparing the liquid interactively driven self-powered wireless sensor of this embodiment are specifically described below. The following content is only for the convenience of understanding the implementation details provided, and is not necessary for the implementation of this solution. The flowchart of the method for preparing the liquid interactively driven self-powered wireless sensor of this embodiment can be as follows: Figure 3 As shown, including:

[0039] Step 301, attaching an electrifying material film to the electromagnetic coil.

[0040] Step 302, attaching an upper electrode to the electrifying material film, and connecting the upper electrode to one end of the electromagnetic coil, so that a capacitor is formed between the upper electrode and the other end of the electromagnetic coil, and the capacitor and the electromagnetic coil form an oscillation circuit;

[0041] Among them, when water droplets fall on the electrifying material film, the water droplets and the electrifying material film generate electricity through friction, so that when the water droplets slide over the upper electrode, the capacitor formed between the upper electrode and the electromagnetic coil is charged, so that the oscillation circuit composed of the capacitor and the electromagnetic coil generates an oscillation signal, and a decay magnetic field is generated around the electromagnetic coil due to the oscillation signal. The electromagnetic coil wirelessly transmits the oscillation signal through the decay magnetic field to realize wireless transmission.

[0042] It is not difficult to find that this embodiment is a preparation method embodiment corresponding to the above wireless sensor embodiment, and this embodiment can be implemented in conjunction with the above wireless sensor embodiment. The relevant technical details and technical effects mentioned in the above embodiment are still valid in this embodiment, and in order to reduce repetition, they are not repeated here. Accordingly, the relevant technical details mentioned in this embodiment can also be applied in the above embodiment.

[0043] In one embodiment, the preparation method of the liquid interactively driven self-powered wireless sensor of the present invention is as follows:

[0044] (1) A charging material film is attached to the electromagnetic coil substrate, wherein the electromagnetic coil with an outer diameter of 70 mm is adjusted to have an inductance value of 10 uH on the PCB by using line width and line spacing, and the charging material film is a PTFE film.

[0045] (2) An upper electrode is attached to the electrifying material film and connected to one end of the electromagnetic coil. The upper electrode is a copper sheet with a width of 1 mm. The capacitance between the upper electrode and the other end of the electromagnetic coil is about 3 pF.

[0046] When a water drop falls on the device and slides over the upper electrode, a decaying magnetic field of about 2.9 MHz is generated around the device. A coupling coil or a magnetic field detection device can be used to monitor the magnetic field signal.

[0047] In one embodiment, the preparation method of the liquid interactively driven self-powered wireless sensor of the present invention is as follows:

[0048] (1) A charging material film is attached to the electromagnetic coil substrate, wherein the electromagnetic coil is changed to a copper sheet without inductance characteristics, and the charging material film is a PTFE film.

[0049] (2) An upper electrode is attached to the electrifying material film and connected to one end of the electromagnetic coil. The upper electrode is a copper sheet with a width of 1 mm. The capacitance between the upper electrode and the other end of the electromagnetic coil is about 1 pF.

[0050] When a water drop falls on the device and slides over the upper electrode, no magnetic field change is generated around the device, and the magnetic field signal cannot be monitored using a coupling coil or magnetic field detection equipment.

[0051] In one embodiment, the preparation method of the liquid interactively driven self-powered wireless sensor of the present invention is as follows:

[0052] The preparation method of the self-powered wireless sensor of the water droplet friction nanogenerator of the present invention is as follows:

[0053] (1) A charging material film is attached to the electromagnetic coil substrate, wherein the electromagnetic coil with an outer diameter of 70 mm is adjusted to have an inductance value of 20 uH on the PCB by using line width and line spacing, and the charging material film is a PTFE film.

[0054] (2) An upper electrode is attached to the electrifying material film and connected to one end of the electromagnetic coil. The upper electrode is a copper sheet with a width of 1 mm. The capacitance between the upper electrode and the other end of the electromagnetic coil is about 2.7 pF.

[0055] When a water drop falls on the device and slides over the upper electrode, a decaying magnetic field of about 2.2 MHz is generated around the device. The magnetic field signal can be monitored using a coupling coil or a magnetic field detection device.

[0056] In one embodiment, the preparation method of the liquid interactively driven self-powered wireless sensor of the present invention is as follows:

[0057] (1) A charging material film is attached to the electromagnetic coil substrate, wherein the electromagnetic coil with an outer diameter of 100 mm is adjusted to have an inductance value of 10 uH on the PCB by using line width and line spacing, and the charging material film is a PTFE film.

[0058] (2) An upper electrode is attached to the electrifying material film and connected to one end of the electromagnetic coil. The upper electrode is a copper sheet with a width of 1 mm. The capacitance between the upper electrode and the other end of the electromagnetic coil is about 3.5 pF.

[0059] When a water drop falls on the device and slides over the upper electrode, a decaying magnetic field of about 2.7 MHz is generated around the device. The magnetic field signal can be monitored using a coupling coil or a magnetic field detection device.

[0060] Those skilled in the art can understand that the above embodiments are specific embodiments of the present invention, and in practical applications, various changes can be made to them in form and detail without departing from the spirit and scope of the embodiments of the present invention. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the embodiments of the present invention, so the protection scope of the embodiments of the present invention shall be based on the scope defined in the claims.

Claims

1. A liquid interactively driven self-powered wireless sensor, characterized in that: include: An upper electrode, an electrifying material film and an electromagnetic coil; The electrifying material film is attached to the electromagnetic coil, the upper electrode is attached to the electrifying material film, and the upper electrode is connected to one end of the electromagnetic coil, so that a capacitor is formed between the upper electrode and the other end of the electromagnetic coil, and the capacitor and the electromagnetic coil form an oscillation circuit; When water droplets fall on the electrifying material film, the water droplets and the electrifying material film generate electricity through friction. When the water droplets slide over the upper electrode, the capacitor formed between the upper electrode and the electromagnetic coil is charged, so that the oscillation circuit composed of the capacitor and the electromagnetic coil generates an oscillation signal. A decay magnetic field is generated around the electromagnetic coil due to the oscillation signal. The electromagnetic coil wirelessly transmits the oscillation signal through the decay magnetic field to achieve wireless transmission.

2. The liquid interactively driven self-powered wireless sensor according to claim 1, characterized in that: The upper electrode is a metal strip made of a conductive material such as copper, platinum, gold or silver, or a metal wire made of a conductive material such as copper, platinum, gold or silver.

3. The liquid interactively driven self-powered wireless sensor according to claim 1, characterized in that: The electrifying material film is prepared from a composite material consisting of polytetrafluoroethylene, polyvinylidene fluoride, polyethylene terephthalate, polyvinyl chloride or fluoropolymer.

4. The liquid interactively driven self-powered wireless sensor according to claim 1, characterized in that: The diameter of the electromagnetic coil is 0.01-200 mm, and the inductance value is 0.01 uH-100 mH.

5. The liquid interactively driven self-powered wireless sensor according to claim 1, characterized in that: The capacitance between the upper electrode and the electromagnetic coil is 0.01 pF to 100 uF.

6. The liquid interactively driven self-powered wireless sensor according to claim 1, characterized in that: The decay magnetic field generated around the upper electrode and the electromagnetic coil is 500kHz-15MHz.

7. The liquid interactively driven self-powered wireless sensor according to claim 1, characterized in that: The electromagnetic coil is placed on a printed circuit board PCB or a flexible printed circuit board FPC.

8. A method for preparing a liquid interactively driven self-powered wireless sensor, characterized in that: include: A film of electrifying material is attached to the electromagnetic coil; An upper electrode is attached to the electrifying material film, and the upper electrode is connected to one end of the electromagnetic coil, so that a capacitor is formed between the upper electrode and the other end of the electromagnetic coil, and the capacitor and the electromagnetic coil form an oscillating circuit; Among them, when water droplets fall on the electrifying material film, the water droplets and the electrifying material film generate electricity through friction, so that when the water droplets slide over the upper electrode, the capacitor formed between the upper electrode and the electromagnetic coil is charged, so that the oscillation circuit composed of the capacitor and the electromagnetic coil generates an oscillation signal, and a decay magnetic field is generated around the electromagnetic coil due to the oscillation signal. The electromagnetic coil wirelessly transmits the oscillation signal through the decay magnetic field to realize wireless transmission.

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