Passive electronic guidance device based on energy harvester

Abstract

The present invention relates to a passive electronic signpost based on an energy harvester, which includes a plurality of electronic light-emitting signposts, a foot pedal, and a plurality of buttons. A power generation device for converting kinetic energy generated when the foot pedal is stepped on into electric energy is provided under the foot pedal, and a power generation device for converting kinetic energy generated when the button is touched into electric energy is provided under the button. The power generation device uses more than one electret thin film energy harvester, and the electret thin film energy harvester is electrically connected to the electronic light-emitting signpost one by one. The passive electronic signpost based on the energy harvester of the present invention does not need to install a power supply, and the line connection is relatively simple, the installation and maintenance costs are low, it does not affect the environment, and it increases the fun.

Description

Technical Field

[0001] The present invention belongs to the technical field of electronic maps, and in particular relates to a passive electronic wayfinding device based on an energy harvester, which is suitable for occasions such as urban parks, living areas, campuses and outdoor mountaineering trails. Background Art

[0002] At present, most of the widely used signposts in urban parks, living areas, campuses, shopping malls and outdoor hiking trails are ordinary map-type signposts. Due to the large area of ​​the park, many buildings or road forks, ordinary map-type signposts are complicated, especially when several location information (such as current location and destination, etc.) need to be displayed at the same time, it is not convenient for tourists to find their way. Although Amap or Baidu Map have good positioning functions, they cannot play their role in areas with weak or no mobile phone signals. In multi-story buildings such as shopping malls, Amap or Baidu Map has the problem of inaccurate navigation location. Therefore, it is very important to install electronic signposts in urban parks, living areas, campuses, shopping malls and outdoor hiking trails to facilitate tourists to find their way.

[0003] Currently commonly used electronic road signs, such as the Chinese patent with patent number CN108761488A, disclose an electronic road sign device and its control method, which include an information input unit, a positioning unit, an audio acquisition unit, a processing unit, a radio frequency processing unit, and an audio playback unit; the information input unit, the positioning unit, the audio acquisition unit, the radio frequency processing unit, and the audio playback unit are respectively connected to the processing unit.

[0004] The currently commonly used electronic road signs require power supply and complex line connections, especially when installed in remote areas of the wild, which will bring huge installation and maintenance costs and may cause certain damage to the environment. The applicant's prior application applied for an invention patent for an energy harvester based on electret film (patent number CN105634323A). If the energy harvester in the prior application is applied to electronic road signs, it is possible to solve the above-mentioned problem that electronic road signs require power supply and complex line connections, and realize passive electronic road signs. Summary of the invention

[0005] Aiming at the problems that traditional electronic road signs need power supply and complex line connection, the present invention proposes a passive electronic road sign device based on an energy harvester.

[0006] In order to achieve the purpose, the technical solution provided by the present invention is:

[0007] A passive electronic guidance device based on an energy harvester comprises an electronic luminous signboard, a pedal, and a plurality of buttons. A power generation device for converting kinetic energy generated when the pedal is stepped on into electrical energy is provided under the pedal. A power generation device for converting kinetic energy generated when the button is touched into electrical energy is provided under the button. The power generation device adopts more than one electret thin film energy harvester, and the electret thin film energy harvester is electrically connected to the electronic luminous signboard.

[0008] Preferably, the electronic luminous sign includes a map indication board and a plurality of light-emitting bodies located below the map indication board, the map indication board is marked with the current position, a plurality of destinations corresponding to the buttons, and the walking routes between the current position and the destinations, and the buttons correspond to the destinations and the walking routes one by one; the electret thin film energy harvester below the foot pedal is electrically connected to the light-emitting body corresponding to the current position on the map indication board, and the electret thin film energy harvester below the buttons is electrically connected to the light-emitting bodies corresponding to the destinations and the walking routes on the map indication board; the map indication board is made of transparent material.

[0009] Preferably, the light emitting body is an LED light emitting diode.

[0010] Preferably, the electronic luminous sign uses a liquid crystal display screen, which is divided into several display areas, one of which corresponds to the current position, and the remaining display areas correspond one by one to the destination and the walking route between the current position and the destination; the electret thin film energy harvester under the foot pedal and the electret thin film energy harvester under the button are respectively connected to the drive control circuit of the liquid crystal display screen.

[0011] Preferably, the foot pedal is installed on the ground in front of the map sign.

[0012] Preferably, the electret film energy harvester comprises an upper electrode, a lower electrode and an electret film. The electret film is a bipolar electret film. The upper and lower surfaces of the electret film are respectively distributed with positive and negative charges. The electret film is arranged between the upper electrode and the lower electrode, and the electret film is not in direct contact with any of the upper and lower electrodes. The upper electrode and the electret film, as well as the lower electrode and the electret film, can be equivalent to two capacitors. The electret film provides fixed induced charges Q1 and Q2 for the variable capacitor. When the upper and lower electrodes vibrate, the air gap between the electret film and the upper and lower electrodes changes, and the induced charges are redistributed. The amount of induced charge change is △Q, thereby supplying power to the light-emitting body.

[0013] Preferably, a spring or an elastic film is provided in the gap between the electret film and the upper electrode, and in the gap between the electret film and the lower electrode.

[0014] Preferably, the electret thin film energy harvester is equipped with a rectifier, which includes diodes D1, D2, D3, and D4. The diodes D1, D2, D3, and D4 are electrically connected in sequence to form a series circuit, and the upper electrode is connected to the connection point of the diodes D1 and D4, and the lower electrode is connected to the connection point of the diodes D2 and D3.

[0015] Preferably, the electret thin film energy harvester is also equipped with a storage capacitor C and a diode D5, one end of the storage capacitor C is connected to the connection point of the diodes D1 and D2, and the other end of the storage capacitor is grounded; the positive electrode of the diode D5 is connected to the connection point of the diodes D1 and D2. The storage capacitor C can store the excess electric energy generated by the electret thin film energy harvester for the next use of the liquid crystal display. The diode D5 is used to control the output voltage.

[0016] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0017] 1. The energy harvester-based electronic luminous signboard of the present invention adopts an electret thin film energy harvester to replace traditional power supply equipment such as batteries and solar cells. The electret thin film energy harvester converts the kinetic energy generated when tourists step on the pedals or touch the buttons into electrical energy for lighting. The entire device does not need to be powered by a power supply, has low installation and maintenance costs, and does not affect the environment.

[0018] 2. The electret film energy harvester involved in the present invention adopts a bipolar electret film as the core material of the micro energy harvester. Compared with energy harvesters of other structures, it has a higher mechanical energy-electrical energy conversion efficiency; the bipolar electret film has a high surface potential and good stability. Using it as the core material of the micro energy harvester can realize independent and self-service provision of stable electric energy to the outside; using an elastic film as a dielectric material can effectively reduce the internal resistance, improve the output power and device application reliability.

[0019] 3. The liquid crystal display screen of the present invention allows users to "interact" with it, display information, and use various "shortcut keys" to perform human-computer interaction, which increases the fun. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic structural diagram of a passive electronic guidance device based on an energy harvester in Example 1;

[0021] Figure 2 It is the circuit schematic diagram of a passive electronic wayfinding device;

[0022] Figure 3 is a circuit schematic diagram of an electret thin film energy harvester in Example 1;

[0023] Figure 4This is a circuit schematic diagram of the electret thin film energy harvester of Example 2;

[0024] Figure 5 This is a usage status diagram of the electronic luminous signboard of Example 1;

[0025] Figure 6 It is a schematic diagram of the structure of the passive electronic guidance device of embodiment 3.

[0026] Illustrations: 1-pedal, 2-electronic luminous sign, 21-map indicator board, 22-luminous body, 23-display area, 3-key area, 31-key, 41-upper electrode, 42-lower electrode, 43-electret film, 44-elastic film, 45-rectifier, 46-spring. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0028] Embodiment 1

[0029] Combined with Figure 1 A passive electronic wayfinding device based on an energy harvester is shown, which can be used in urban parks, living areas, campuses, and outdoor hiking trails. In this embodiment, the passive electronic wayfinding device based on the energy harvester is set on campus, including an electronic luminous signboard 2, a pedal 1, and a plurality of buttons 31. A power generation device for converting the kinetic energy generated when stepping on the pedal into electrical energy is provided under the pedal, and a power generation device for converting the kinetic energy generated when the button is touched is provided under the button. The power generation device uses more than one electret thin film energy harvester, and the electret thin film energy harvester is electrically connected to the electronic luminous signboard.

[0030] The electronic luminous sign 2 includes a map indication board 21 and a plurality of luminous bodies 22 located below the map indication board 21. The map indication board 21 is marked with the current position, a plurality of destinations corresponding to the buttons, and the walking routes between the current position and the destinations. The buttons correspond to the destinations and the walking routes one by one. The electret film energy harvester below the pedal 1 is electrically connected to the luminous body corresponding to the current position on the map indication board, and the electret film energy harvester below the button 31 is electrically connected to the luminous body 22 corresponding to the destination and the walking route on the map indication board. The map indication board 21 is made of transparent material.

[0031] A plurality of buttons 31 are uniformly installed in the button area 3, which is located at one side of the electronic light-emitting indicator board 2. The foot pedal 1 is installed on the ground in front of the map indicator board.

[0032] The working principle of this passive electronic guidance device is:

[0033] Electret film energy harvesters are provided below the pedal 1 and the button 31, and the pedal 1 is installed on the ground in front of the electronic light-emitting sign 2. When the user needs route instructions, the user stands on the pedal 1 with the electronic light-emitting sign 2 in front of him. Since the electret film energy harvester under the pedal 1 is electrically connected to the light-emitting body 22 corresponding to the current position on the map indication board 21, the electret film energy harvester generates current to light up the light-emitting body 22 corresponding to the current position on the map indication board 21, thereby displaying the current position on the map indication board 21. The user selects the destination he wants to go to in the button area 3, for example Figure 5 As shown, "Seven Teachings" is selected, and the user touches the "Seven Teachings" button, then the electret film energy harvester under this button 31 generates current, lighting up the light-emitting body 22 corresponding to the destination and the walking route on the map indication board 21, thereby displaying the destination and the walking route on the map indication board 21.

[0034] Combined with Figure 2 , 3 As shown, the electret film energy harvester comprises an upper electrode 41, a lower electrode 42 and an electret film 43. The electret film 43 is 3×3 cm in size. 2 , a bipolar electret composite film with a thickness of 2mm and a maximum amplitude of 1.2mm. The electret film 43 adopts a bipolar electret film, and the upper and lower surfaces of the electret film are respectively distributed with positive and negative charges. The electret film 43 is arranged between the upper electrode 41 and the lower electrode 42, and the electret film does not contact any of the upper electrode and the lower electrode. An elastic film 44 with different elastic modulus and dielectric constant is arranged in the gap between the electret film 43 and the upper electrode 41, and in the gap between the electret film 43 and the lower electrode 42. The function of the elastic film 44 is to provide elastic force, so that the distance between the electret film 43 and the upper electrode 41 or the lower electrode 42 changes, and the output current and voltage drive the capacitance between the electret film and the electrode to change, causing the amount of induced charge on the electrode to change, and the output current and voltage. At the same time, considering that the output current of a single electret thin film energy harvester is relatively weak, the power generation device of the present invention recommends using multiple electret thin film energy harvesters to increase the output current and voltage through series / parallel connection to adapt the electrical parameters of the light-emitting body.

[0035] The power generation principle of this electret film energy harvester is:

[0036] The above-mentioned electret film 43 undergoes thermal polarization and corona polarization, and its internal dipole and space charge are polarized and characterized by surface equivalent charge. After corona discharge on the surface, the surface of the film has a very high voltage. The electret film 43 induces charges Q1 and Q2 on the upper and lower electrodes through its own electric field. At this time, the upper electrode 41 and the electret film 43 and the lower electrode 42 and the electret film 43 are equivalent to variable capacitors. Initially, the electret film 43 provides a fixed induced charge for the variable capacitor; when the air gap between the electret film 43 and the upper and lower electrodes changes, the charges between the two plates will be rearranged, and the induced charge change is △Q, thereby supplying power to the light-emitting body 22.

[0037] Combined with Figure 2 and 3 The electret thin film energy harvester is also equipped with a rectifier 45, an energy storage capacitor C and a diode D5. The rectifier 45 includes diodes D1, D2, D3, and D4. The diodes D1, D2, D3, and D4 are electrically connected in sequence to form a series circuit. The upper electrode is connected to the connection point of the diodes D1 and D4, and the lower electrode is connected to the connection point of the diodes D2 and D3; one end of the energy storage capacitor C is connected to the connection point of the diodes D1 and D2, and the other end of the energy storage capacitor is grounded. The energy storage capacitor C can store the excess electric energy generated by the electret thin film energy harvester for the light-emitting body 22 to use next time; the positive electrode of the diode D5 is connected to the connection point of the diodes D1 and D2, and the diode D5 is used to control the output voltage.

[0038] The energy storage capacitor C has the characteristics of long cycle charge and discharge time, simple charging circuit and long life. The whole power generation device is equivalent to an AC power supply, which charges the energy storage capacitor after rectification; when the voltage across the energy storage capacitor is greater than the voltage drop of the diode D5, the voltage is output to the outside.

[0039] Embodiment 2

[0040] Combination Figure 4 As shown, the electret film energy harvester of this embodiment has made certain improvements on the basis of the first embodiment. Specifically, a spring 46 is provided in the gap between the electret film 43 and the upper electrode 41, and in the gap between the electret film 43 and the lower electrode 42. In this embodiment, the spring 46 is used to replace the elastic film 44, and the function of the spring 46 is the same as that of the elastic film 44 in the first embodiment.

[0041] Embodiment 3

[0042] Combination Figure 6As shown, a passive electronic wayfinding device based on an energy harvester can be used in urban parks, living areas, campuses, and outdoor hiking trails. In this embodiment, the passive electronic wayfinding device based on the energy harvester is set in the campus, including an electronic luminous signboard 2, a pedal 1, and a plurality of buttons 31. A power generation device for converting the kinetic energy generated when stepping on the pedal into electrical energy is provided under the pedal 1. A power generation device for converting the kinetic energy generated when the button is touched into electrical energy is provided under the button 31. The power generation device adopts more than one electret thin film energy harvester, and the electret thin film energy harvester is electrically connected to the electronic luminous signboard.

[0043] The electronic luminous sign 2 adopts a liquid crystal display screen, which is divided into a plurality of display areas 23, one of which corresponds to the current position, and the remaining display areas 23 correspond to the destination and the walking route between the current position and the destination respectively; the electret thin film energy harvester under the pedal and the electret thin film energy harvester under the button are respectively connected to the driving control circuit of the liquid crystal display screen.

[0044] The power generation principle of the electret thin film energy harvester in this embodiment is the same as that in the first embodiment, and will not be described in this embodiment. The electronic light-emitting sign 2 in this embodiment uses a liquid crystal display screen, which is usually equipped with a universal drive control circuit. The drive control circuit can use a single-chip microcomputer AT89C51 or the like.

[0045] When a person stands on the pedal 1, the electret thin film energy harvester under the pedal 1 generates current, and the driving control circuit of the liquid crystal display screen controls the corresponding display area 23 to light up, and the display area displays the "current location" pattern. When a key 31 is pressed, the electret thin film energy harvester under the key 31 generates current, and the driving control circuit of the liquid crystal display screen controls the corresponding display area 23 to light up, and the display area displays the "destination and walking route" pattern corresponding to the key 31.

[0046] A plurality of buttons 31 are uniformly installed in the button area 3, which is located at one side of the electronic light-emitting indicator board 2. The foot pedal 1 is installed on the ground in front of the map indicator board.

[0047] The present invention is described in detail above in conjunction with the embodiments, but the contents described are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made according to the scope of application of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A passive electronic guidance device based on an energy harvester, characterized in that: It includes an electronic luminous sign, a foot pedal, and a plurality of buttons. A power generation device for converting kinetic energy generated when the foot pedal is stepped on into electric energy is provided under the foot pedal. A power generation device for converting kinetic energy generated when the button is touched into electric energy is provided under the button. The power generation device uses more than one electret thin film energy collector, and the electret thin film energy collector is electrically connected to the electronic luminous sign; The electronic luminous sign includes a map indication board and a plurality of luminous bodies located below the map indication board, wherein the map indication board is marked with a current position, a plurality of destinations corresponding to buttons, and a walking route between the current position and the destination, and the buttons correspond to the destinations and the walking routes one by one; the electret film energy collector below the pedal is electrically connected to the luminous body corresponding to the current position on the map indication board, and the electret film energy collector below the button is electrically connected to the luminous body corresponding to the destination and the walking route on the map indication board; Alternatively, the electronic light-emitting signboard adopts a liquid crystal display screen, which is divided into a plurality of display areas, one of which corresponds to the current position, and the remaining display areas correspond to the destination and the walking route between the current position and the destination; The electret film energy harvester under the foot pedal and the electret film energy harvester under the button are respectively connected to the driving control circuit of the liquid crystal display screen; The electret film energy harvester comprises an upper electrode, a lower electrode and an electret film. The electret film adopts a bipolar electret film. The upper and lower surfaces of the electret film are respectively distributed with positive and negative charges. The electret film is arranged between the upper electrode and the lower electrode, and the electret film is not in direct contact with any of the upper electrode and the lower electrode.

2. The passive electronic guidance device based on energy harvester according to claim 1, characterized in that: The map indicator board is made of transparent material.

3. The passive electronic guidance device based on energy harvester according to claim 2, characterized in that: The illuminant is an LED (light emitting diode).

4. The passive electronic guidance device based on energy harvester according to claim 1, characterized in that: The foot pedal is installed on the ground in front of the map sign.

5. The passive electronic guidance device based on energy harvester according to claim 1, characterized in that: A spring or an elastic film is provided in the gap between the electret film and the upper electrode, and in the gap between the electret film and the lower electrode.

6. The passive electronic map indicator board based on energy harvester according to claim 1 or 5, characterized in that: The electret thin film energy harvester is equipped with a rectifier, which includes diodes D1, D2, D3, and D4. The diodes D1, D2, D3, and D4 are electrically connected in sequence to form a series circuit, the upper electrode is connected to the connection point of the diodes D1 and D4, and the lower electrode is connected to the connection point of the diodes D2 and D3.

7. The passive electronic map indicator board based on energy harvester according to claim 6, characterized in that: The electret film energy harvester is also equipped with a storage capacitor C and a diode D5. One end of the storage capacitor C is connected to the connection point of the diodes D1 and D2, and the other end of the storage capacitor is grounded. The positive electrode of the diode D5 is connected to the connection point of the diodes D1 and D2.

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