WO2014017184A1

WO2014017184A1 - Vibration power generation body and method for producing same

Info

Publication number: WO2014017184A1
Application number: PCT/JP2013/065856
Authority: WO
Inventors: 健彦水野; 考洋金谷
Original assignee: 株式会社ビスキャス
Priority date: 2012-07-25
Filing date: 2013-06-07
Publication date: 2014-01-30
Also published as: JP5691080B2; JP2014027756A

Abstract

A vibration power generation body (1) is primarily composed of an electret dielectric (3), electrodes (5a, 5b), and spacers (7). The electrodes (5a, 5b) are positioned on both surface of the electret dielectric (3) in such a manner as to face the electret dielectric (3). Both surfaces of the electret dielectric (3) are charged by charges that are opposite to each other. Furthermore, the electret dielectric (3) is constructed with a porous material (e.g., a resin foam). In other words, minute pores (4) are formed inside the electret dielectric (3).

Description

Vibration power generator and method of manufacturing the same

The present invention relates to a vibration power generator using an electret dielectric.

Conventionally, electrical energy includes vibrations of structures such as roads, bridges, buildings, and industrial machines, vibrations of moving bodies such as automobiles, railway vehicles, and aircraft, and environmental vibrations that are universally present in human movement and the environment. Attempts have been made to make effective use by converting to.

Such power generation methods that convert vibration energy into electricity can be broadly divided into methods that use electromagnetic induction, methods that use piezoelectric elements, and methods that use electrostatic induction. The system using electromagnetic induction is a system in which the relative position between the coil and the magnet is changed by vibration and power is generated by electromagnetic induction generated in the coil. The method using a piezoelectric element mainly uses a ceramic-based piezoelectric element and utilizes a phenomenon in which charges are induced on the surface of the piezoelectric element when strain is applied to the piezoelectric element by vibration.

In addition, an electret dielectric that holds a charge semipermanently is generally used for a system that uses electrostatic induction. By changing the relative position of the electret dielectric and the electrode disposed at a distance from the dielectric by vibration or the like, electric charges are electrostatically induced in the electrode, and power generation is performed. A power generation device using such a principle is described in, for example, Patent Document 1 and Patent Document 2.

JP 2010-136598 A JP 2000-50394 A

In the vibration power generation apparatus described in Patent Document 1, a plurality of strip-shaped base electrodes are arranged in parallel on the upper surface of a fixed substrate, and electrets are formed on the respective base electrodes. The movable substrate faces the surface of the fixed substrate on which the electret is disposed, and is disposed in parallel with a predetermined gap. Further, a strip-shaped counter electrode is formed on the counter surface of the movable substrate so as to oppose the base electrode. When vibration is applied, the movable substrate moves in parallel while maintaining a distance from the fixed substrate. Therefore, the relative position between the electret and the counter electrode changes in a parallel direction. At this time, electric power can be electrostatically induced in each electrode to generate power.

Patent Document 2 describes an electret condenser microphone that converts sound waves into electrical signals. In an electret condenser microphone, an electret dielectric film is formed on a cup-shaped back electrode that is a fixed electrode, and a vibration film that is a counter electrode is formed on the side facing the electret dielectric film. Further, the gap between the electret dielectric film and the vibration film is held by a spacer. When the sound wave propagates from the center hole and the vibration film vibrates, the relative position between the vibration film and the electret dielectric film changes. At this time, a charge is electrostatically induced in each electrode. The electric signal thus obtained can be output after signal amplification and impedance conversion.

Here, the electret dielectric is used after being charged in advance. Even in the above-described power generation method, electret dielectric charging is an important process in order to obtain sufficient power generation. However, in general, the electret dielectric surface is charged by using corona discharge by a corona discharge generator provided outside the electret dielectric, so that the charge processing step becomes large.

In addition, it is difficult for the above-described conventional power generation apparatus and the like to correspond to a wide variety of attachment site forms. For example, in the devices described in Patent Documents 1 and 2, and methods using electromagnetic induction and piezoelectric elements, each member is formed in a substantially rigid manner, so that it is inferior in flexibility such as changing the shape according to the attachment site. .

In the electret condenser microphone as disclosed in Patent Document 2, since the linearity between the input sound wave and the output electric signal is important, the obtained electric signal is small and the impedance of the power generation unit is high. For this reason, the electricity generated by the power generation unit is amplified by the semiconductor circuit and subjected to impedance conversion. Therefore, an external power source for driving the semiconductor circuit is necessary, and the generated electric energy cannot be effectively used in the first place.

The present invention has been made in view of such problems, and it is an object of the present invention to provide a vibration power generator and the like having high power generation efficiency that can be easily charged and can be applied to various installation locations. And

In order to achieve the above-described object, the first invention comprises a pair of electrodes and an electret dielectric that is provided between the pair of electrodes and retains electric charges, and the electret dielectric is empty inside. A flexible material composed of a porous material having pores, and when an external force is applied, the distance between at least one of the pair of electrodes and the electret dielectric changes at least in part. The vibration power generator is characterized in that it is possible.

With this configuration, a vibration power generator with a high degree of freedom in installation can be obtained. In particular, since there are holes in the electret dielectric, air discharge can be easily generated in the holes during electret dielectric charging. Therefore, by applying a voltage in the thickness direction of the electret dielectric, the electret dielectric can be charged using air discharge in the holes inside the electret dielectric, and the applied voltage required for the charging is compared. Therefore, the electret dielectric can be easily charged. In other words, in the case of an electret dielectric that does not have holes, the applied voltage required for charging the front and back surfaces of the electret dielectric is relatively high by applying a voltage in the thickness direction. The electret dielectric surface is charged by an external corona discharge generator. Compared to this case, the electrification process of the porous electret dielectric material having pores is facilitated.

Also, since the electret dielectric is flexible, the obtained vibration power generator can be deformed according to the installation location. At this time, since the electret dielectric is a porous material, the electret dielectric can be easily deformed in the thickness direction, and each electret dielectric can be deformed in the thickness direction (a partial change in the thickness of the electret dielectric). Electric charges are electrostatically induced in the electrodes, and power generation can be performed. Further, the electret dielectric can be reduced in weight.

A non-joining portion that is not joined to each other is formed between at least one of the electrodes and the electret dielectric, and when an external force is applied, at least a portion of the non-joining portion includes at least the electret dielectric, It is desirable that the distance to one of the electrodes can be changed.

With this configuration, when the vibration power generator receives an external force, the distance between the electret dielectric and the electrode changes in the thickness direction at the non-joint portion between the electret dielectric and the electrode. Accordingly, electric charges are electrostatically induced in each electrode, and power generation can be performed. That is, the vibration power generator of the present invention composed of a porous electret dielectric having pores inside is deformed in the thickness direction of the electret dielectric (a partial change in the thickness of the electret dielectric), Due to both the change in the distance between the electret dielectric and the electrode at the non-joined portion, electric charge is electrostatically induced in each electrode, and power can be generated.

It should be noted that the deformation by external force is not limited to the case where another material mechanically contacts the vibration power generator to deform the vibration power generator. For example, the vibration power generator can be deformed by being repeatedly applied to the vibration power generator, such as vibration of the structure itself that occurs at the attachment portion of the vibration power generator, external sound wave or air pressure change, wind (air flow), water flow, etc. It refers to the action of force from the outside to the vibration power generator. This external force may be minute. In addition, the vibration in the vibration power generator is not limited to the one whose amplitude or frequency is constant, but refers to one that can apply external force (including inertial force) repeatedly or irregularly. .

A spacer is partially provided between the electret dielectric and at least one of the electrodes, and the electret dielectric and the electrode are joined via at least a part of the spacer, and other than the spacer It is good also considering a site | part as the said non-joining part.

With such a configuration, it is possible to easily maintain the gap between the electret dielectric and the electrode by the thickness of the spacer. Therefore, the distance between the electret dielectric and the electrode can be changed more reliably according to the external force.

One of the pair of electrodes is a center electrode, the other is an external electrode, the electret dielectric is provided on an outer periphery of the center electrode, and the external electrode is provided on an outer periphery of the electret dielectric, It is good also as a structure by which the outer periphery of the external electrode was coat | covered with the coating | coated part.

With such a configuration, a cable-like vibration power generator with a high degree of freedom in installation can be obtained. In addition, such a cable-like vibration power generator is capable of at least partial deformation of the interface shape between the external electrode and the electret dielectric by an external force, so that the change in the relative position between the center electrode and the external electrode is possible. Can generate electricity.

A second invention is a method for manufacturing a vibration power generator, comprising: a pair of electrodes; and an electret dielectric that is a porous body provided between the pair of electrodes and having pores therein. A non-bonding portion that is not bonded to each other between at least one of the electrodes and the electret dielectric, and using a vibration power generator before charging treatment having a gap in at least a part of the non-bonding portion, A method of manufacturing a vibration power generator, characterized in that a voltage is applied between electrodes to cause discharge in the holes or in the gaps to charge the electret dielectric.

By using such electret dielectric charging method, electret dielectric charging in the vibration power generator manufacturing process is facilitated. That is, it is not necessary to provide a corona discharge generator outside, and a high voltage power source for applying a voltage between a pair of electrodes sandwiching the electret dielectric may be used as an alternative. Further, as described above, the voltage required for the charging process of the porous electret dielectric having pores may be a relatively low voltage, so that the charging process is facilitated. Furthermore, since the electret dielectric charging process can be positioned as the final step of manufacturing the vibration power generator, the vibration power generator can be easily manufactured.

In the present application, the term “electret dielectric” may be used not only for the charged state but also for the base material before the charging process.

According to the present invention, it is possible to provide a vibration power generator and the like having high power generation efficiency that can be easily applied to an installation place in various forms because the electret dielectric can be easily charged.

FIG. 1A is a diagram showing a vibration power generator 1, and FIG. 1B is a diagram showing a vibration power generator 1a. 2A is a diagram showing the electret dielectric 3, and FIG. 2B is an enlarged view of a portion J in FIG. 2A. FIG. 3A and FIG. 3B are conceptual diagrams showing a deformed state of the electrode 5 b and the electret dielectric 3. FIG. 4A is a view showing the vibration power generation body 30, and FIG. 4B is a view showing the vibration power generation body 30a. Sectional drawing which shows the vibration electric power generation body. FIG. 6A and FIG. 6B are diagrams showing a charged state of the electret dielectric 3. FIG. 7A and FIG. 7B are conceptual diagrams showing deformation states of the external electrode 43 and the electret dielectric 3. FIG. 8A and FIG. 8B are conceptual diagrams showing a change in the distance between the electret dielectric 3 and the external electrode 43. FIG. 9A is a cross-sectional view showing the vibration power generation body 40a, and FIG. 9B is a cross-sectional view showing the vibration power generation body 40b. FIGS. 10A, 10 </ b> B, and 10 </ b> C are diagrams showing a configuration in which the electret dielectric 3 is formed with the resin tape 51. The figure which shows the change of the electric power generation output voltage of a vibration electric power generation body. The figure which shows the vibration electric power generating apparatus 60. FIG. The figure which shows the comparison of the electric power generation output voltage of a vibration electric power generation body. The figure which shows the comparison of the electric power generation output voltage of a vibration electric power generation body. The figure which shows the comparison of the electric power generation output voltage of a vibration electric power generation body.

<Embodiment 1>
Hereinafter, the vibration electric power generation body 1 concerning embodiment of this invention is demonstrated. As shown in FIG. 1A, the vibration power generator 1 is mainly composed of an electret dielectric 3, electrodes 5a and 5b, a spacer 7, and the like.

Electrodes 5a and 5b are disposed on both sides of the electret dielectric 3 so as to face the electret dielectric 3, respectively. A spacer 7 is provided between the electret dielectric 3 and the electrodes 5a and 5b. The spacer 7 is for maintaining a gap between the electret dielectric 3 and the electrodes 5a and 5b. That is, the electret dielectric 3 and the electrodes 5a and 5b are joined via the spacer 7, and the portion that is not joined to each other via the spacer 7 becomes the non-joined portion 9, and the thickness of the spacer 7 is between them. A corresponding gap 6 (gap) is formed.

As the spacer 7, for example, a conductive or semiconductive material can be used, but it is preferable that the spacer 7 is made of an insulating material. Moreover, it is desirable that at least a part of all the spacers 7 is made of an adhesive or adhesive member. For example, the spacer 7 is partially formed of an adhesive member or the like to such an extent that the electret dielectric 3 and the electrodes 5a and 5b can be bonded and fixed, and the non-adhesive spacer 7 is provided at other portions. It may be used. The details of the spacer 7 will be described later.

In the present invention, the electret dielectric 3 and the electrodes 5a and 5b are both flexible. For example, the electrodes 5a and 5b can be formed of a metal foil that can be easily deformed, such as a metal foil having flexibility such as aluminum or copper. The electret dielectric 3 is made of, for example, a flexible resin that is a porous material having insulating properties. Therefore, the vibration power generation body 1 has flexibility as a whole, and can be modified to suit various installation locations.

As shown in FIG. 2A, both surfaces of the electret dielectric 3 are charged with charges having opposite polarities. Moreover, the electret dielectric material 3 is comprised with a porous material (for example, foamed resin etc.). That is, as shown in FIG. 2B, fine holes 4 are formed inside the electret dielectric 3.

Such an electret dielectric 3 can be charged on the surface using, for example, an electron irradiation method using an external charge source, a DC corona discharge method using an external corona generator, or an AC corona discharge method. In particular, the charging process can be easily performed by generating corona discharge on the surface of the base material of the electret dielectric 3.

Here, when a voltage is applied to the front and back surfaces (thickness direction) of the electret dielectric 3, corona discharge can be easily generated in the holes 4. Therefore, the corona discharge facilitates charging the hole 4 wall surface and the electret dielectric 3 near the hole 4 wall surface. As shown in FIG. 2B, the charge on the wall surface of the hole 4 and in the vicinity of the wall surface of the hole 4 is positive and negative along the voltage application direction (in this case, the thickness direction of the electret dielectric 3). It is considered that a region charged with electric charge is formed. Similarly, in the gap 6 formed in the non-joint portion 9 between the electret dielectric 3 and the electrodes 5a and 5b, corona discharge easily occurs in the gap 6 when a voltage is applied in the thickness direction of the vibration power generator 1. Can be made. Therefore, regions charged with positive charges and negative charges are formed on the front and back surfaces of the electret dielectric 3, respectively. Therefore, as described above, as a method for manufacturing the vibration power generator 1 and a method for charging the electret dielectric 3, for example, after electrifying the surface of the electret dielectric 3 using an external corona generating device, the electret dielectric There is a method of manufacturing the vibration power generator 1 by sandwiching the body 3 between the electrodes 5 a and 5 b and joining the electret dielectric 3 and the electrodes 5 a and 5 b via the spacer 7. Alternatively, before electret dielectric 3 is charged, electret dielectric 3 and electrodes 5a and 5b are bonded via spacer 7, and a voltage is applied between electrodes 5a and 5b in this state. A method of manufacturing the vibration power generator 1 by performing the electrification process of the electret dielectric 3 can also be adopted. Here, the latter method does not require the use of an external corona generator, and the electret dielectric 3 can be charged in the final step of the manufacturing process of the vibration power generator 1. Thus, the manufacture of the vibration power generator 1 and the electret dielectric 3 charging process are facilitated.

Also, since the holes 4 are present inside the electret dielectric 3, the electret dielectric 3 as a whole can be easily deformed. Therefore, the thickness of the electret dielectric 3 itself can be partially changed with a smaller external force. Therefore, although details will be described later, electric power can be generated by electrostatic induction of each electrode. That is, in addition to the power generation due to the change in the distance (gap length) between the electret dielectric 3 and the electrodes 5a and 5b in the gap 6 (non-joined portion 9), the electret dielectric 3 itself has a partial thickness change. Since power generation can be performed, power generation efficiency can be improved.

As described above, the electret dielectric 3 can be easily charged by using a porous material having pores 4 as the electret dielectric 3. For example, the electret dielectric 3 can be charged with a lower applied voltage as compared with the case where the holes 4 are not formed. The voltage applied to the base material of the electret dielectric 3 may be an alternating voltage or a direct voltage.

Here, at the time of electrification processing of the electret dielectric 3, electrodes 5a and 5b may be used as electrodes sandwiching the electret dielectric 3 of the porous material, or electrodes for electrification treatment may be used separately. Further, as a charging method other than the electrification dielectric charging process by voltage application or corona discharge, for example, when the electret dielectric 3 is composed of a nonwoven fabric, the charging process is performed by water current collision with sufficient pressure. Also good. Alternatively, the liquid mixture with an organic solvent or water may be passed through the non-woven fabric and then quickly dried to perform the charging treatment. Alternatively, the charging process may be performed by frictionally charging two types of fibers having different charge trains.

In the manufacturing process of the vibration power generator 1, the timing at which the electret dielectric 3 is charged is not particularly limited, and may be appropriately set according to the selected charging method. For example, the structure of the vibration power generator 1 may be assembled by using the electret dielectric 3 that has been previously charged. Alternatively, during the manufacturing process of the vibration power generator, the electret dielectric 3 may be charged using a corona generator or the like in a state where the base material of the electret dielectric 3 is incorporated as a part of the constituent members of the vibration power generator 1. Good. Alternatively, the charging process may be performed as a final process after the configuration of the vibration power generator is completely assembled.

Also, the holes 4 have a function of easily deforming the electret dielectric 3 itself by the holes 4 as well as for facilitating the charging process. Therefore, the vibration power generator 1 can be easily deformed with a smaller external force. For this reason, power generation efficiency can be improved. Further, the electret dielectric 3 is lightened by the holes 4.

Here, the electret dielectric 3 has a large charge amount (for example, a potential difference V ₀ [V] between the front and back surfaces of the electret dielectric 3), the electret dielectric 3 has a small thickness d [m], and the electret dielectric 3 As the relative dielectric constant ε _r is larger, the generated power of the vibration power generator 1 tends to increase. This is because the dielectric constant in vacuum is ε ₀ (= 8.854 × 10 ⁻¹² F / m), and the surface charge density charged on both surfaces of the electret dielectric 3 is + σ [C / m ² ], − When σ [C / m ² ] is assumed, the surface charge density is expressed by the following formula, and the larger the surface charge density σ, the larger the generated power of the vibration power generator 1.

In general, the occurrence of air discharge in the gap (gap) between the electrodes 5a and 5b and the electret dielectric 3 is determined by the gap length and the potential difference between the gaps, and approximately follows Paschen's law. Therefore, when the external force is not applied, and with respect to the change range of the gap length between the electrodes 5a and 5b and the electret dielectric 3 when the external force is applied, the electret is set so as to have a potential difference between the gaps where no air discharge occurs. It is desirable to set the potential difference V ₀ between the front surface and the back surface of the dielectric 3. For example, if the gap length (or the thickness of the spacer 7) when no external force is applied is 100 μm, the change range of the gap length when an external force is applied is 0 to 100 μm. With respect to the change range of the gap length, air discharge occurs when the potential difference V ₀ between the front surface and the back surface of the electret dielectric 3 is set to about 600 V or more. On the other hand, when air discharge occurs, the potential difference V ₀ between the front and back surfaces of the electret dielectric 3 after the occurrence of discharge is about 200 to 600V. Therefore, in the present invention, when the gap length is 100 μm, it is desirable to perform the charging process so that V ₀ is about 200 to 600V.

Note that the occurrence of air discharge in the gap 6 (gap) between the electrodes 5a and 5b and the electret dielectric 3 also depends on the manufacturing method of the vibration power generator 1 and the electret dielectric 3 charging method. For example, the electret dielectric 3 that has been previously charged is incorporated as an oscillating power generator 1 together with an electrode, the case where the electrification is performed during manufacture (incorporation), and the case where the electrification is performed after manufacture (incorporation). Since the range of the distance change between the electret dielectric 3 and the electrodes 5a and 5b during the production of each vibration power generator 1 and the range of the potential difference generated between the two differ, the conditions for generating air discharge are different. Therefore, in the selected method for manufacturing the vibration power generator 1, it is desirable to set the potential difference V ₀ between the front and back surfaces of the electret dielectric 3 that does not generate air discharge between the electret dielectric 3 and the electrodes 5 a and 5 b.

The electret dielectric 3 may use an insulating porous plastic sheet or porous plastic film, or an insulating porous rubber sheet or porous rubber film, or a sheet-like fiber body made of fibers of an insulating material. it can. Examples of the plastic include resins such as polyethylene, polypropylene, polyethylene terephthalate, and polyvinyl chloride. Further, depending on the use conditions, for example, a polyimide-based resin or a fluorine-based resin (for example, fluoroethylenepropylene or polytetrafluoroethylene) having excellent high-temperature characteristics can be used. As the rubber, for example, nitrile rubber, ethylene propylene rubber, acrylic rubber, urethane rubber, chloroprene rubber, silicone rubber, fluorine-based rubber, and the like can be used.

Further, as the insulating sheet-like fiber body, non-woven fabric or felt can be used in addition to woven fabric. Especially, the nonwoven fabric is utilized for the electret filter used for an air cleaner, a mask, etc., and has the characteristic of a favorable electret. As the material of such a nonwoven fabric, the same material as that of the plastic described above can be used.

As shown in FIG. 1A, a non-joining portion 9 is formed between the electret dielectric 3 and the electrodes 5a and 5b at a portion other than those joined via the spacer 7, and a gap 6 (gap) is formed. Exists. That is, in the non-joint part 9 (gap 6), the distance between the electret dielectric 3 and the electrodes 5a and 5b is easily changed by deformation. For example, the electrodes 5a and 5b can be brought into contact with the surface of the electret dielectric 3 by deformation of the electrodes 5a and 5b.

<About the power generation mechanism of the vibration power generator 1>
Next, the power generation mechanism of the vibration power generator 1 will be described. 3 (a) and 3 (b) are enlarged views of part A in FIG. As shown in FIG. 3A, for example, in a steady state (a state in which no external force is applied; the same applies hereinafter), a gap 6 between the electrode 5b and the electret dielectric 3 is formed in the gap 6 at the non-joint portion 9. A gap length B corresponding to the thickness of the spacer 7 is formed. From this state, as shown in FIG. 3B, when the external force C is applied in the thickness direction of the vibration power generator 1, the electrode 5b (and the electret dielectric 3) is deformed, and the gap length B is reduced. Change direction. Here, depending on the magnitude and time of the external force C to be applied, the electrode 5b and the electret dielectric 3 are in contact with each other at the contact portion 11 as shown in FIG.

At this time, the position corresponding to the contact portion 11 can be changed until the distance (gap length B) in the thickness direction between the electrode 5b and the electret dielectric 3 becomes zero. Further, in the contact portion 11, after the electrode 5 b and the electret dielectric 3 are contacted, the electret dielectric 3 is deformed by the external force C, and the thickness of the electret dielectric 3 is changed. Therefore, it is considered that electric charges of opposite polarity are electrostatically induced in each of the electrode 5a and the electrode 5b in accordance with a change in the distance (gap length B) between the electrode 5b and the electret dielectric 3 in the thickness direction. It is done. In addition, the dipole moment of the dipole formed by the charges charged with different polarities on the front and back surfaces and inside of the electret dielectric 3 (in the vicinity of the holes 4) causes deformation (thickness of the electret dielectric 3). Change). At that time, it is considered that charges of opposite polarity are electrostatically induced in each of the electrodes 5a and 5b sandwiching the electret dielectric 3 in accordance with the change in the thickness of the electret dielectric 3 to generate power. Similarly, when returning from the state of FIG. 3B to the state of FIG. 3A, the change in the distance in the thickness direction (gap length B) between the electrode 5b and the electret dielectric 3 and the electret dielectric 3 are the same. Electricity is generated by electrostatic induction according to the change in the thickness of the substrate. Here, the polarities of the charges induced in the electrodes 5a and 5b change in the direction in which the distance between the electrode 5b and the electret dielectric 3 approaches, and in the direction in which the thickness of the electret dielectric 3 decreases. The case where the distance between the electrode 5b and the electret dielectric 3 is changed in the direction away from each other and the thickness of the electret dielectric 3 is changed in the opposite direction is opposite. Therefore, the output voltage obtained from the vibration power generator 1 when a repeated external force change (including vibration) is applied is an alternating voltage. Although details will be described later, the power generation output voltage accompanying the change in the distance between the electrode 5b and the electret dielectric 3 and the change in the thickness of the electret dielectric 3 is immediately before the electrode 5b and the electret dielectric 3 come into contact with each other due to deformation. And immediately after peeling.

As described above, in the present invention, the electrodes 5a and 5b are deformed in the thickness direction with respect to the electret dielectric 3, and the gap length B is changed, and the thickness of the electret dielectric 3 itself is changed. Can generate electricity. In addition, in order to generate electric power efficiently with the whole vibration electric power generation body 1, the direction of the distance change (decrease direction or increase direction) of electrode 5a, 5b and the electret dielectric material 3, and the thickness of the electret dielectric material 3 It is desirable that the change direction (decreasing direction or increasing direction) and the timing (phase) thereof coincide with each other in each part of the vibration power generator 1. For example, when the electrodes 5a and 5b and the electret dielectric 3 are repeatedly contacted and peeled, it is desirable to match the timing of the contact and peeling between the parts of the vibration power generator 1.

Here, the portion where the spacer 7 is arranged depends on the material, but the thickness of the spacer 7 is less likely to change compared to the change in the gap length of the non-joining portion 9 (gap 6) with respect to the application of external force. . That is, the distance between the electrodes 5a and 5b and the electret dielectric 3 is unlikely to change at the portion where the spacer 7 is disposed. For this reason, the site | part in which the spacer 7 is arrange | positioned does not contribute easily to electric power generation. Therefore, it is desirable to make the spacer 7 as small as possible and make the total area of the spacer 7 in the vibration power generator 1 as small as possible. In addition, it is desirable to dispose the spacers 7 at a predetermined distance from each other to such an extent that the gap length B can be maintained with respect to the non-joining portion 9 (gap 6). Further, as described above, the planar arrangement of the spacers 7 on the front and back of the electret dielectric 3 is made in order to match the timing and the direction of the distance change between the electrodes 5a and 5b and the electret dielectric 3 on the front and back of the electret dielectric 3. It is desirable to match.

Note that the spacers 7 are arranged on the surface of the electret dielectric 3 in a shape (form) such as a dot shape, a stripe shape, and a lattice shape with a predetermined interval. When the spacer 7 has a dot shape, the shape of the spacer 7 in plan view may be an arbitrary shape such as a circle, an ellipse, a square, or a rectangle. At this time, it is desirable to make the area occupied by the vibration power generator 1 of each spacer as small as possible and to widen the non-joining portion 9.

When the vibration power generator 1 is repeatedly deformed by an external force, the electrodes 5a and 5b and the electret dielectric 3 are repeatedly contacted and peeled, but at this time, the gap between the electrodes 5a and 5b and the electret dielectric 3 is repeated. 6 is considered to cause air discharge. When such air discharge occurs, the potential difference between the front and back surfaces of the electret dielectric 3 may be reduced. Therefore, there is a possibility that power generation is not performed as the vibration power generator 1 is used. However, the inventors have found that even if the electrodes 5a and 5b and the electret dielectric 3 are repeatedly contacted and separated from each other, the power generation output of the vibration power generator 1 is immediately reduced and power generation is not performed. I found that there was nothing. The generation of air discharge in the gap 6 between the electrodes 5a, 5b and the electret dielectric 3 is considered to approximately follow Paschen's law as described above. Therefore, the distance between the electrodes 5a and 5b in the gap 6 and the electret dielectric 3 and the electrification potential of the electret dielectric 3 (potential difference between the front and back surfaces of the electret dielectric 3) are expressed by the air discharge according to Paschen's law. It is desirable to set in a range where no occurrence occurs.

Moreover, in this invention, as shown in FIG.1 (b), the vibration electric power generation body 1a in which the spacer 7 was provided only between one electrode 5b and the electret dielectric material 3 can also be used. The vibration power generation body 1 a has substantially the same configuration as the vibration power generation body 1, but the electrode 5 a is directly bonded to the electret dielectric 3 over the entire surface without the spacer 7. In this case, a gap 6 (non-joined portion 9) is formed by the spacer 7 disposed between the one electrode 5b and the electret dielectric 3. Therefore, power generation can be performed by a mechanism similar to that of the vibration power generator 1. Also in this case, it is desirable that the potential difference V ₀ between the front surface and the back surface of the electret dielectric 3 is about 200 to 600 V for the reasons described above.

The electrode 5a and the electret dielectric 3 may be fused by, for example, heat fusion. Or you may adhere | attach both with an adhesive agent or an adhesive. Or you may join both with an adhesive tape. For the adhesive, the pressure-sensitive adhesive, and the pressure-sensitive adhesive tape, a conductive material or a semiconductive material can be used, but a member having high insulation (high electrical resistivity) is desirable. However, when using an adhesive, a pressure-sensitive adhesive, or a pressure-sensitive adhesive tape, it is desirable to make their thickness as thin as possible. For example, it is desirable to make it sufficiently thin with respect to the distance between the electrodes 5 a and 5 b and the thickness of the electret dielectric 3.

Since the electrode 5a is joined to the entire surface of the electret dielectric 3 in the vibration power generator 1a, power is generated by a change in the distance between the one electrode 5b and the electret dielectric 3 and a change in the thickness of the electret dielectric 3. However, in the vibration power generator 1 that generates power by changing the distance between each of the electrodes 5 a and 5 b and the electret dielectric 3 and changing the thickness of the electret dielectric 3, for example, each of the electrodes 5 a and 5 b and the electret dielectric If the distance change direction and the timing (phase) of both of the body 3 and the body 3 do not coincide with each other, the power generation output voltages generated between the electrodes 5a and 5b may cancel each other. Therefore, it is necessary to match the direction and timing (phase) of the distance change between each of the electrodes 5 a and 5 b and the electret dielectric 3.

On the other hand, in the vibration power generator 1a, power is generated by a change in the distance between the one electrode 5b and the electret dielectric 3 and a change in the thickness of the electret dielectric 3, so that the electrode 5a, There is no need to match the direction and timing (phase) of the distance change between each of 5b and the electret dielectric 3. Further, compared with the vibration power generation body 1 of FIG. 1A, the vibration power generation body 1 a can be reduced in total thickness by the thickness of the spacer 7. In this way, the vibration power generator 1a can be used in consideration of the cost reduction due to the simplification of the structure and the point that the thickness can be reduced.

As mentioned above, since the electret dielectric 3 is comprised with the porous material which has the void | hole 4 inside the vibration electric power generation body of this Embodiment, the electrification process is easy. Moreover, since the member becomes flexible by the air holes 4, it can be easily deformed. Accordingly, since the electret dielectric 3 can be easily deformed even with a small external force, the power generation efficiency is good. Moreover, the vibration electric power generation body 1 can be freely bent and installed according to the form of the installation part. In addition, the vibration power generator 1 can be reduced in weight by the holes 4.

Further, the spacer 7 can maintain a predetermined gap length between the electrodes 5 a and 5 b and the electret dielectric 3. For this reason, it is possible to secure a deformation allowance of the electrodes 5a and 5b due to an external force (a deformation allowance in the thickness direction in which the distance between the electrodes 5a and 5b and the electret dielectric 3 changes). In addition, by optimizing the thickness of the spacer 7, the contact and peeling between the electrodes 5a and 5b and the electret dielectric 3 can be repeated. For this reason, high power generation can be obtained. Note that power generation can be efficiently performed by setting the thickness of the spacer 7 that holds the gap length to 30 μm to 100 μm.

<Embodiment 2>
Next, another embodiment will be described. In the following description, components having the same functions as those of the vibration power generator 1 are denoted by the same reference numerals as those in FIG.

The vibration power generation body 30 shown in FIG. 4A has substantially the same configuration as that of the vibration power generation body 1, but differs in that electrodes 31a and 31b are used instead of the electrodes 5a and 5b. The electrodes 31 a and 31 b are configured by laminating a conductive layer 33 and a resin layer 35, and are arranged so that each conductive layer 33 faces the electret dielectric 3.

Such electrodes 31a and 31b may be obtained by bonding a resin sheet and a metal foil by an adhesive, heat welding, or the like, or by performing metal vapor deposition or metal plating on the surface of the resin sheet. Good. In any case, it is sufficient that the conductor layer can be formed on the sheet (film) resin. The conductor can be appropriately selected from aluminum, tin, copper, and alloys thereof.

In addition, as such resin, resin, such as polyethylene, a polypropylene, a polyethylene terephthalate, can be used, for example. Further, depending on the use conditions, for example, a polyimide-based resin or a fluorine-based resin (for example, fluoroethylenepropylene or polytetrafluoroethylene) having excellent high-temperature characteristics can be used. In addition, rubber materials such as nitrile rubber, ethylene propylene rubber, acrylic rubber, urethane rubber, chloroprene rubber, silicone rubber, and fluorine rubber can also be used.

By using the electrodes 31a and 31b having a two-layer structure, it is possible to improve the followability of the electrode with respect to an external force or the like. For example, with only a thin conductor, after being deformed by an external force, the restoring force to the original shape becomes small. However, if the rigidity is increased only with the conductor, there is a problem of an increase in weight because it is necessary to increase the thickness of the conductor portion. In addition, this may cause the movement of the electrode to become dull.

On the other hand, in the present embodiment, by providing the resin layer 35, it is possible to suppress problems due to weight increase and increase the followability of the electrodes 31a and 31b with respect to external force, that is, rigidity. Moreover, electrical insulation between the electrodes 31a and 31b and the external environment can be achieved. In this embodiment, one electrode 31a may be directly joined to the electret dielectric 3 over the entire surface without using the spacer 7, as in the vibration power generator 30a shown in FIG.

<Embodiment 3>
Next, a vibration power generator 40 according to still another embodiment will be described. As shown in FIG. 5, the vibration power generator 40 having a cable shape mainly includes a center electrode 41, an electret dielectric 3, an external electrode 43, a covering portion 45, and the like.

A center electrode 41 is provided at the center of the vibration power generator 40. An electret dielectric 3 is provided on the outer periphery of the center electrode 41. An external electrode 43 is provided on the outer periphery of the electret dielectric 3. That is, the electret dielectric 3 is sandwiched between the center electrode 41 and the external electrode 43. A covering portion 45 is provided on the outer periphery of the external electrode 43. As described above, the vibration power generator 40 is a cable in which the center electrode 41, the electret dielectric 3, the external electrode 43, and the covering portion 45 are arranged coaxially.

When an external force is applied, at least the mutual interface shape of the external electrode 43 and the electret dielectric 3 can be partially deformed in a cross section perpendicular to the length direction of the vibration power generator 40. Further, the center electrode 41, the electret dielectric 3 and the external electrode 43 are each flexible, and the vibration power generator 40 can be bent and deformed into an arbitrary form.

As the center electrode 41 and the external electrode 43, a highly conductive material is desirable, but a semiconductive material may be used. As the conductive material, for example, a metal such as aluminum, copper, tin, iron, or an alloy thereof can be used. In addition, the surface of these metals may be plated with tin, silver, zinc, nickel or the like.

The center electrode 41 may be formed by, for example, twisting a single conductor wire or a plurality of conductor wires. The external electrode 43 can be formed by, for example, a metal braided wire, a metal tape winding, a spiral winding of a conductor wire, or the like, but considering flexibility and durability due to external force, a metal braid A line is desirable.

As shown in FIG. 6A, the electret dielectric 3 is positively charged on the center electrode 41 side which is the inner surface side and negatively charged on the outer electrode 43 side which is the outer surface side. That is, both surfaces of the electret dielectric 3 are semi-permanently charged with opposite polarities. Such an electret dielectric 3 can be formed by performing a predetermined charging process. As shown in FIG. 6B, the electret dielectric 3 may be negatively charged on the center electrode 41 side which is the inner surface side and positively charged on the outer electrode 43 side which is the outer surface side. Here, inside the electret dielectric 3, the holes 4 (FIG. 2B) are formed inside as described above.

<About the power generation mechanism of the vibration power generator 40>
Next, the power generation mechanism of the vibration power generator 40 will be described. As shown in FIG. 7A, for example, in a steady state (a state in which no external force is applied; the same applies hereinafter), a distance corresponding to the thickness of the electret dielectric 3 is provided between the center electrode 41 and the external electrode 43. Is maintained.

On the other hand, as shown in FIG. 7B, for example, when a compressive force (force in the direction of arrow G in the figure) is applied from the outside, the mutual interface shape of the external electrode 43 and the electret dielectric 3 is partially Deforms. Accordingly, both the thickness of the electret dielectric 3 and the distance between the center electrode 41 and the external electrode 43 change. At this time, according to the deformation (change in thickness) of the electret dielectric 3 and the relative position change between the center electrode 41 and the external electrode 43, charges having different polarities are induced in the respective electrodes, thereby generating power. To do.

As described above, the mechanism by which charges are induced in the center electrode 41 and the external electrode 43 can be considered as follows. On both surfaces of the electret dielectric 3, the dipole moment of the dipole formed by charges charged with different polarities changes as the electret dielectric 3 is deformed. At this time, it is considered that charges having opposite polarities are electrostatically induced in the center electrode 41 and the external electrode 43 disposed on the inner surface side and the outer surface side of the electret dielectric 3, respectively, to generate electric power.

Further, since the relative position between the center electrode 41 and the external electrode 43 partially changes, the capacitance between the center electrode 41 and the external electrode 43 changes. Therefore, it is considered that the electric charge induced in each electrode changes due to the presence of the electret dielectric 3 to generate power.

Actually, the center electrode 41 and the external electrode 43 are different from each other in that the amount of charge to be charged is different between the inner surface side and the outer surface side of the electret dielectric 3 and that the constituent members are arranged coaxially. The mechanism by which electric charges are induced is complicated. However, regardless of which mechanism is assumed, the polarity of the charges induced in the center electrode 41 and the external electrode 43 is such that the thickness of the electret dielectric 3 is small and the distance between the center electrode 41 and the external electrode 43 is The case of deformation in the approaching direction and the case of deformation in the direction in which the thickness of the electret dielectric 3 increases and the distance between the center electrode 41 and the external electrode 43 increases are opposite.

On the other hand, even if an external force is applied to the vibration power generation body 40, no charge is induced in the center electrode 41 and the external electrode 43 in a state where the shape of the vibration power generation body 40 does not change (a state where the deformation is stopped). No power is generated. At this time, when the impedance of the external circuit electrically connected to the center electrode 41 and the external electrode 43 is very large, if the impedance is infinite, no charge flows through the external circuit, and the vibration power generator 40 The amount of charge induced in the center electrode 41 and the external electrode 43 is held until the change in the shape of is stopped. Therefore, the potential difference between the center electrode 41 and the external electrode 43 corresponding to the amount of charge held is maintained. On the other hand, when the impedance of the external circuit electrically connected to the center electrode 41 and the external electrode 43 is low, electric charge flows through the external circuit, so that the potential difference between the center electrode 41 and the external electrode 43 is zero. Become. From the above, the output voltage obtained from the vibration power generator 40 when a repeated external force change (including vibration) is applied is an alternating voltage.

Further, it is desirable that a non-joint portion is formed between the electret dielectric 3 and at least one of the center electrode 41 or the external electrode 43. That is, it is desirable that the electret dielectric 3 can be easily separated from the center electrode 41 and the external electrode 43. Further, as shown in FIG. 8A, the electret dielectric 3 may not be completely in contact with the center electrode 41 or the external electrode 43, and a gap may be partially formed. In the illustrated example, part I of FIG. 8A shows a state in which the external electrode 43 and the electret dielectric 3 are separated and a gap 6 is generated therebetween.

From this state, for example, when an external force change in the radial direction of the vibration power generation body 40 (in the direction of arrow H in the figure) occurs and the mutual interface shape between the external electrode 43 and the electret dielectric 3 is partially deformed, FIG. As shown, the contact state at the non-joint portion between the external electrode 43 and the electret dielectric 3 changes. For example, part I of FIG. 8B shows a state where the external electrode 43 and the electret dielectric 3 shown in part I of FIG. 8A have changed from a peeled state to a contacted state. Yes. At this time, since the electret dielectric 3 itself is easily deformed by an external force, the thickness of the electret dielectric 3 itself also changes. That is, the distance between the external electrode 43 and the electret dielectric 3 partially changes, and the thickness of the electret dielectric 3 also changes at the portion where the external electrode 43 and the electret dielectric 3 are in contact with each other. And the external electrode 43 partially change in distance.

By doing in this way, in the interface in the non-junction part of the electret dielectric material 3 and the center electrode 41 or the external electrode 43, the area | region where a mutual contact, peeling, or friction arises at the time of deformation | transformation of the vibration electric power generation body 40 can be formed. And the thickness of the electret dielectric 3 itself can be partially changed. At this time, electric charges are induced in the center electrode 41 and the external electrode 43, and power generation can be performed.

As described above, the mechanism by which the charge is induced in each electrode by changing the contact state at the non-junction portion between the electret dielectric 3 and the center electrode 41 or the external electrode 43 is considered as follows.

First, by repeating contact and peeling between the electret dielectric 3 and the center electrode 41 or the external electrode 43 at the non-joint portion, the surface of the electret dielectric 3 and the respective surfaces of the center electrode 41 or the external electrode 43 The relative position of changes. Moreover, formation and disappearance of an air layer are repeated between the electret dielectric 3 and the center electrode 41 or the external electrode 43 by repeating peeling and contact. At that time, it is considered that charges having different polarities are induced in each electrode by electrostatic induction. Further, in the region where the electret dielectric 3 and the center electrode 41 or the external electrode 43 are repeatedly contacted and peeled, an external force is also applied to the electret dielectric 3, so that the thickness of the electret dielectric 3 also changes. In particular, the thickness of the porous electret dielectric material 3 having the pores 4 therein is easily changed by an external force as compared with the case where the pores 4 are not provided. At this time, since the dipole moment of the electret dielectric 3 changes due to the change in the thickness of the electret dielectric 3, it is considered that charges having different polarities are induced by the electrostatic induction.

Secondly, there is a phenomenon of charging (peeling charging, contact charging, frictional charging, etc.) when contact, delamination or friction occurs between the electret dielectric 3 and the center electrode 41 or the external electrode 43. The electric charge is generated in each of the central electrode 41 and the external electrode 43 to generate electric power. The charging phenomenon when different kinds of substances come into contact with each other, peel off, and friction is a complicated phenomenon because the charge amount and polarity differ depending on the state and conditions at that time. Therefore, in the present invention, it is considered that the former is dominant in the mechanism in which charges are induced in each electrode in accordance with the change in the contact state between the electret dielectric 3 and the center electrode 41 or the external electrode 43.

In addition, the inventors can contact and peel the electret dielectric 3 and each electrode from each other in a non-bonded state, rather than the case where the electret dielectric 3 is completely bonded to the center electrode 41 and the external electrode 43. It has been found that the power generation output voltage is larger in the state. Therefore, in the vibration power generation body 40 in which the non-junction portion is provided between the electret dielectric 3 and the center electrode 41 or the external electrode 43, the power generation due to the change in the dipole moment accompanying the deformation of the electret dielectric 3 described above. However, it is considered that the power generation accompanying the change in the contact state at the non-joint portion between the electret dielectric 3 and the center electrode 41 or the external electrode 43 is dominant.

The

vibration power generators

1, 1a, 30, 30a shown in FIGS. 1 (a), 1 (b), 4 (a), and 4 (b) have the gap 6 held by the spacer 7 so that the external force By providing the above, it is possible to change the distance between each electrode and the electret dielectric 3 in the non-joining portion 9 other than the spacer 7. However, even if the spacer 7 is used, the gap length of the non-joined portion 9 may not be kept constant. Therefore, in the non-joined part 9, the electrodes 5a and 5b and the electret dielectric 3 may be in partial contact even when no external force is applied. However, as described above, if the distance in the thickness direction between the electrodes 5a and 5b and the electret dielectric 3 can be partially changed by an external force (FIGS. 8A and 8B), the electrode 5a 5b can induce charge. Therefore, the spacer 7 is not necessarily required if the

vibration power generators

1, 1a, 30, and 30a are partially formed with non-joining portions.

<Embodiment 4>
As described above, the vibration power generator 40 of the present invention can generate power in response to deformation caused by an external force. Therefore, it is desirable that the vibration power generator 40 be easily deformed. For this reason, as shown in FIG. 9A, a vibration power generator 40a having a hollow center electrode 41 may be used. In the vibration power generation body 40a, since the space 47 is formed inside the center electrode 41, the deformation of the cross section of the vibration power generation body 40a by an external force is easy.

Further, as shown in FIG. 9B, a vibration power generation body 40b in which an elastic body 49 is disposed inside the hollow center electrode 41 may be used. As the elastic body, one that can be easily deformed and has a high shape restoring force is desirable. For example, a rubber string member or a wire member can be used. In this case, the center electrode 41 may be formed on the outer surface of the elastic body 49 by metal deposition, metal plating, or the like. Further, the center electrode 41 may be formed by winding a metal tape or a metal wire around the outer periphery of the elastic body 49. Further, the center electrode 41 may be formed by covering the outer periphery of the elastic body 49 with, for example, a copper braided wire in a tubular shape. The cross-sectional shape of the center electrode 41 may not be a perfect circle, but may be an ellipse or other shapes.

<About the manufacturing method of the vibration electric power generation body 40>
Next, a method for manufacturing the vibration power generator 40 will be described. The electret dielectric 3 can be formed by extruding and covering an insulating foamed plastic or foamed rubber on the outer periphery of the center electrode 41. After the base material of the electret dielectric 3 made of insulating foamed plastic or foam rubber is extruded and coated, an external electrode 43 is formed on the outer periphery, and the covering portion 45 is extruded and coated on the outer periphery of the external electrode 43. Thereafter, a DC voltage may be applied between the center electrode 41 and the external electrode 43 to charge the electret dielectric 3.

Further, as in the present invention, when the holes 4 are dispersed and exist inside the electret dielectric 3, or when a gap exists between the electret dielectric 3 and the center electrode 41 or the external electrode 43. As described above, a DC voltage may be applied between the center electrode 41 and the external electrode 43, but the electret dielectric 3 can be charged by applying an AC voltage. At this time, when the AC voltage is applied, air discharge can be generated in the gap portion or the hole portion with a lower applied voltage than when the DC voltage is applied. It is easy to form a charged region inside. Accordingly, the electret dielectric 3 can be easily charged.

The electret dielectric 3 may be formed by other methods. For example, the resin tape 51 may be formed by winding the resin tape 51 around the center electrode 41 so as to form one or more layers.
In this case, as shown to Fig.10 (a), the resin tape 51 may be wound helically so that each edge part may wrap (wrap winding). Further, as shown in FIG. 10B, the resin tapes 51 may be spirally wound with a gap 6 therebetween so that a gap is formed between the end portions (gap winding).

When the resin tape 51 is wrapped or a gap is wound, a spiral gap 6 is formed between the layers of the resin tape 51 wound around a plurality of layers. The gap 6 functions as the hole 4 of the present invention. That is, even if the resin tape 51 is made of a material without pores, the electret dielectric 3 formed by winding the resin tape 51 is the same as the electret dielectric 3 formed of the porous material described above. Work. That is, the gap 6 functions as the hole 4 of the present invention.

It should be noted that the resin tape 51 may be made of the same material as the electret dielectric 3 described above. That is, as the resin tape 51, an insulating porous plastic tape, porous rubber tape, fiber tape, or the like can be used. When the resin tape 51 made of a porous material is used, as shown in FIG. 10C, the resin tape 51 is abutted with no gap so that no wrap portion or gap portion is formed at each end portion. It may be wrapped around (butt wrap). Further, one layer or a plurality of layers may be wound with a resin tape vertically attached to the center conductor.

Also, electrification treatment can be performed before the external electrode 43 is formed after the base material of the electret dielectric 3 made of insulating foam plastic or foam rubber is extruded and coated on the outer periphery of the center electrode 41. That is, for example, after the base material of the electret dielectric 3 is extruded and coated on the outer periphery of the center electrode 41, the surface of the electret dielectric 3 is charged using an external corona discharge generator, and then the external electrode 43 and the covering portion 45 are charged. Can be sequentially formed to manufacture the vibration power generator 40. When the resin tape 51 is used, the charging process may be performed after the resin tape 51 is wound, or the resin tape 51 that has been previously charged may be wound.

<Relationship between the deformation of the vibration power generator 40 and the power generation output voltage>
FIG. 11 is a diagram illustrating a result of evaluating the relationship between the deformation of the vibration power generation body 40 and the power generation output voltage, where the horizontal axis represents time and the vertical axis represents the power generation output voltage. As the vibration power generator 40, a copper wire having a diameter of 1 mm was used for the center electrode 41, and the electret dielectric 3 was provided by extruding and covering a foamed polypropylene having a thickness of about 1 mm on the center electrode. A tin-plated copper braided wire was used for the external electrode 43, and polyvinyl chloride having a thickness of about 0.5 mm was used for the covering portion 45. In addition to the expanded polypropylene, expanded foam, expanded polyvinyl chloride, expanded silicone rubber, expanded ethylene propylene rubber is extruded on the center electrode 41 with a thickness of about 1 mm for the electret dielectric 3 and has the same configuration. The power generator 40 was similarly evaluated.

The obtained vibration power generator 40 was subjected to polarization charging treatment of the electret dielectric 3 by applying a DC voltage of 4 kV for 1 hour between the center electrode 41 and the external electrode 43 at room temperature. Regarding the polarity of the DC voltage, both the case where the central electrode 41 side is a negative electrode and the external electrode 43 side is a positive electrode and vice versa were evaluated. Further, in any vibration power generation body 40, the electret dielectric 3, the center electrode 41, and the external electrode 43 are in a non-bonded state, and deformation, deformation, or friction between the vibration power generation body 40 can occur. It is. Here, for the sake of simplicity, the relationship between the deformation of the vibration power generation body 40 of FIG. 11 and the power generation output voltage will be described by focusing on the changes in the interface shape and the contact state between the external electrode 43 and the electret dielectric 3.

FIG. 11 shows an example of observing, using an oscilloscope, a power generation output waveform when a pressing force is applied to the vibration power generation body 40 and the pressing force is removed after holding for a certain period of time. Here, the input impedance of the oscilloscope was DC 1 MΩ. Further, the potential of the electrode facing the surface side where the negative charge of the electret dielectric 3 is charged was used as the reference potential.

First, in the steady state, power generation is not performed when the interface shape and the contact state between the external electrode 43 and the electret dielectric 3 are not changed. From this state, when the vibration power generation body 40 is pressed and deformed, the interface shape between the external electrode 43 and the electret dielectric 3 in the pressed area changes. For example, in a portion where a gap is formed as shown in part I of FIG. 8A, the distance between the external electrode 43 and the electret dielectric 3 is small as shown in part I of FIG. 8B. Will eventually change to touch. In the region where the external electrode 43 and the electret dielectric 3 are in contact with each other, an external force (pressing) acts on the electret dielectric 3, so that the electret dielectric 3 is also deformed and the thickness of the electret dielectric 3 is reduced. Change. At the same time, in the pressed area, the distance between the external electrode 43 and the center electrode 41 also changes in the direction of decreasing. At this time, a positive voltage is generated in the vibration power generator 40 (I in FIG. 11).

Thereafter, when the change in shape of the vibration power generation body 40 is stopped in a state where the pressure is applied to the vibration power generation body 40, the mutual interface shape and contact state between the external electrode 43 and the electret dielectric 3 change, and the electret dielectric The thickness change of 3 stops. If the interface shape and the contact state of each other and the thickness of the electret dielectric 3 are maintained in this way, the vibration power generator 40 does not generate power and induces both the center electrode 41 and the external electrode 43 before that. Since the generated charge flows through the input impedance of the oscilloscope, the power generation output voltage of the vibration power generator 40 becomes 0 (II in FIG. 11). When the pressure is released from this state, the shape of the vibration power generation body 40 in the area subjected to the pressure is deformed so as to return to the shape in the original steady state. For this reason, the mutual interface shape and contact state between the external electrode 43 and the electret dielectric 3, and the thickness of the electret dielectric 3 also return to the interface shape and contact state in the steady state and the thickness of the electret dielectric 3. It will be transformed into. That is, the external electrode 43 and the electret dielectric 3 are deformed in a peeling direction (a direction in which both distances are separated), and the thickness of the electret dielectric 3 is changed in an increasing direction. At the same time, in the region where the pressure is released, the distance between the external electrode 43 and the center electrode 41 also changes in a direction that increases. At this time, a negative voltage having a polarity opposite to that described above is generated in the vibration power generator 40 (III in FIG. 11). Subsequently, when the shape change of the vibration power generator 40 stops after releasing the pressure, the mutual interface shape and contact state between the external electrode 43 and the electret dielectric 3 and the thickness of the electret dielectric 3 change. Stops, and the vibration power generator 40 does not generate power. At this time, similarly to the above, since the charge previously induced in both the center electrode 41 and the external electrode 43 flows through the input impedance of the oscilloscope, the power generation output voltage of the vibration power generator 40 becomes zero. .

As described above, in the present invention, the shape of the interface between the electret dielectric 3 and the external electrode 43 or the center electrode 41 in the vibration power generator 40 and the change in the contact state (contact and peeling), and further the deformation of the electret dielectric 3 Due to the change in thickness due to, power can be generated with high efficiency. Such a tendency was the same even when the material of the electret dielectric 3 was changed. The same tendency was observed even when the electret dielectric 3 was charged with the opposite polarity.

In addition, it was confirmed that the vibration

power generation bodies

1, 1a, 30, 30a, 40a, and 40b have the same relationship between the deformation of the vibration power generation body and the power generation output voltage as shown in FIG. In particular, by providing the spacer 7 between the electrode and the electret dielectric 3 and forming the gap 6, higher power generation was obtained. Specifically, in the process of applying pressure and deforming, the largest generated output voltage was shown immediately before the electrode contacted the electret dielectric 3. Also, in the process of returning to the original steady state even when the pressure is released, the power generation output voltage was the largest immediately after the electrode was peeled from the electret dielectric 3. Therefore, it is desirable that the electrode and the electret dielectric 3 repeat contact and peeling when the vibration power generator is deformed.

Moreover, the

vibration power generators

1, 1a, 30, 30a, 40, 40a, 40b according to the present invention can be used by connecting them in series or in parallel. By doing so, a larger power generation output voltage can be obtained. In this case, for example, electrodes in which positive charges are induced and electrodes in which negative charges are induced may be connected in parallel, or electrodes in which charges of different polarities are induced may be connected in series. Further, the

vibration power generators

1, 1a, 30, 30a, 40 may be laminated in a plurality of layers, arranged in a plurality on the plane, or may be arranged in combination.

Moreover, since the

vibration power generator

1, 1a, 30, 30a, 40, 40a, 40b according to the present invention has flexibility, the vibration power generator can be bent and used. For example, the

vibration power generators

1, 1a, 30, 30a may be used in a folded state. In this case, a plurality of vibration power generators are stacked and the electrodes are connected in parallel with the polarities aligned. The same effect as the case can be obtained. Further, the vibration power generators 40, 40a, and 40b can be used in a state of being bent in a spiral shape.

<Embodiment 5>
Next, a method for storing the power generation output generated by the

vibration power generator

1, 1a, 30, 30a, 40, 40a, 40b according to the present invention will be described. As shown in FIG. 12, the vibration power generator 60 includes the vibration power generator 1, a rectifier circuit 67, a power storage circuit 69, and the like. In addition, although the example using the vibration electric power generation body 1 is demonstrated in FIG. 12, it is applicable similarly to the vibration electric

power generation bodies

1a, 30, 30a, 40, 40a, 40b.

As the rectifier circuit 67, a full-wave rectifier circuit in which four diodes 61 are combined is used. The rectifier circuit 67 rectifies the output voltage from the vibration power generator 1. The power storage circuit 69 includes a power storage unit 63 such as a capacitor and a rechargeable battery, and a switch 65. The diode 61 preferably has a low forward resistance, a high reverse resistance, a fast time response speed, and a small loss. Further, it is desirable that the capacitor or the battery has a small leakage current in a charged state and a small charging loss.

As described above, the output voltage of the vibration power generator 1 when a repeated external force is applied is alternating current. Therefore, it is desirable that the output voltage of the vibration power generator 1 is rectified by the rectifier circuit 67 and the output of the rectifier circuit 67 is stored in the storage circuit 69.

When a plurality of vibration power generation bodies 1 are used, the electrodes 5a and 5b of all vibration power generation bodies 1 may be connected in parallel and then connected to the rectifier circuit 67. On the other hand, it is desirable to provide a rectifier circuit 67. That is, it is desirable to provide a rectifier circuit 67 for each vibration power generator 1 and connect it, and connect the output from each rectifier circuit 67 to the power storage circuit 69 in parallel with the same polarity. This is to prevent a decrease in power generation output due to cancellation of each other's power generation output when the timing of power generation and the polarity of the power generation output voltage in each vibration power generator 1 do not match. In addition, even when there is no mutual cancellation of the power generation output, when the vibration power generation body 1 that does not generate power is included, the vibration power generation body 1 that does not generate power as an external load with respect to the other vibration power generation bodies 1 that generate power This is to prevent a decrease in power generation output due to functioning.

The power generation output voltage was evaluated using various vibration power generators shown below.

(Example 1)
In Example 1, the structure shown in the vibration power generation body 30 (FIG. 4A) was adopted. The size of the vibration power generator was about 100 mm × about 100 mm × about 0.5 mm. The electrodes 31a and 31b were formed by using a 12 μm thick aluminum foil as the conductive layer 33 and using a 100 μm thick PET (polyethylene terephthalate) film as the resin layer 35 and bonding them by thermal welding. As the electret dielectric 3, a foamed polypropylene film having a thickness of 100 μm was used, and the entire foamed polypropylene film was uniformly charged by corona discharge. The potential difference between both surfaces of the electret dielectric 3 was about 200V.

In addition, as the spacer 7, an insulating adhesive was used. The aluminum foil surfaces of both electrodes and the electret dielectric 3 were adhered by applying an insulating adhesive in the form of dots using a mask pattern so as to be equally spaced two-dimensionally in the plane direction. The adhesion pattern after adhesion was a circle having a diameter of about 1 mm, a thickness of 100 μm, and the spacers were arranged at equal intervals. That is, the gap length between the electret dielectric 3 and each of the electrodes 31a and 31b was 100 μm. The distance between the centers of the spacers 7 was 10 mm, and the arrangement relationship of the spacers 7 provided on both surfaces of the electret dielectric 3 was arranged at the same position in plan view.

(Example 2)
Example 2 is substantially the same as Example 1, but has the structure shown in the vibration power generator 30a (FIG. 4B). The size of the vibration power generator was about 100 mm × about 100 mm × about 0.4 mm. The electrodes 31a and 31b and the electret dielectric 3 are the same as in the first embodiment. Note that the aluminum foil surface (conductive layer 33) of one electrode 31a is bonded to the electret dielectric 3 by heat fusion. The other electrode 31b and the electret dielectric 3 were coated with dots in the same manner as in Example 1 to form spacers 7.

(Comparative Example 1)
Comparative Example 1 is substantially the same as Example 1, except that a 100 μm thick polypropylene film that is not a porous material is used as the electret dielectric 3.

(Comparative Example 2)
Comparative Example 2 was substantially the same as Example 2, but a 100 μm thick polypropylene film that was not a porous material was used as the electret dielectric 3.

(Comparative Example 3)
Comparative Example 3 is substantially the same as Example 2, except that electrodes 31 a and 31 b on both sides are bonded to the entire surface of the electret dielectric 3. That is, the entire surfaces of the electrodes 31a and 31b and the electret dielectric 3 were bonded to each other without forming a non-bonded portion with respect to any of the electrodes on both sides.

(Comparative Example 4)
Comparative Example 4 is substantially the same as Example 2, except that a 100 μm thick polypropylene film that is not a porous material is used as the electret dielectric 3, and the electrodes 31 a and 31 b on both sides are bonded to the entire surface of the electret dielectric 3. did. That is, the entire surfaces of the electrodes 31a and 31b and the electret dielectric 3 were bonded to each other without forming a non-bonded portion with respect to any of the electrodes on both sides.

FIG. 13 shows the evaluation results of the power generation output voltage when the same vibration (vibration frequency is 1 Hz) is applied to the vibration power generators of Examples 1 to 2 and Comparative Examples 1 to 4. In addition, as a power generation output voltage, the power generation output voltage of the vibration power generation body of Example 1 is set to 1, and the normalized relative power generation output voltage is shown.

13, Examples 1 and 2 in which a porous material is applied as the material of the electret dielectric 3 showed a relatively high power generation output voltage compared to Comparative Examples 1 and 2 that are not porous materials. This is the same even if the comparative example 3 and the comparative example 4 are compared. That is, by using the electret dielectric 3 which is a porous material, the electret dielectric 3 is easily deformed, and as a result, the power generation output voltage is improved.

Moreover, although the comparative example 3 uses the porous material, since the electrodes 31a and 31b and the electret dielectric 3 are adhered on the entire surface, the power generation output voltage is inferior to those of Examples 1 and 2. However, compared with Comparative Example 4 in which the electret dielectric 3 has no holes, the power generation output voltage is remarkably large, and the power generation output voltage is improved by making the electret dielectric 3 porous. Moreover, when a gap is formed by providing a non-joining portion between the electrodes 31a and 31b and the electret dielectric 3, the power generation output voltage is further improved.

Further, as is clear from comparison between Example 1 in which the gap is formed on both sides of the electret dielectric 3 and Example 2 in which the gap is formed on only one side, the generated output voltage is higher when the gap is formed on both sides. Although there is a tendency, the difference is small. This is the same even if the comparative example 1 and the comparative example 2 are compared. That is, in consideration of manufacturability, use environment, and handleability of the vibration power generator, whether the gap is formed on both surfaces or only one surface may be appropriately set.

As described above, a porous material is used as the electret dielectric, and a higher power generation output voltage can be obtained by forming a gap (non-joined portion) between at least one electrode and the electret dielectric. As a result.

In addition, although illustration is abbreviate | omitted, in Example 2, several vibration electric power generation bodies 1a which changed gap length (adhesive thickness or spacer thickness) are manufactured, and the electrode 5b and the electret dielectric material 3 repeat a contact and peeling. When such external force (vibration) was repeatedly applied, the power generation output voltage increased as the gap length increased. That is, when the electrode 5b and the electret dielectric 3 are repeatedly contacted and peeled, the power generation output voltage increases as the amount of change in the distance between the electrode 5b and the electret dielectric 3 increases.

However, when the gap length exceeds 100 μm, the increase amount of the generated output voltage with respect to the increase amount of the gap length becomes smaller. Further, when the gap length is increased, the external force or vibration necessary for bringing the electrode 5b and the electret dielectric 3 into contact with each other also increases. Further, the total thickness of the vibration power generator is increased by increasing the gap length. Therefore, the gap length (spacer thickness) is preferably 100 μm or less.

(Example 3)
Next, the vibration power generator shown in the vibration power generator 40 (FIG. 5) was evaluated. In Example 3, a copper wire having a diameter of 1 mm was used for the center electrode 41, and as the electret dielectric 3, foamed polypropylene having a thickness of about 1 mm was extruded and coated on the center electrode 41. A tin-plated copper braided wire was used for the external electrode 43, and polyvinyl chloride having a thickness of about 0.5 mm was used for the covering portion 45.

The obtained vibration power generator was subjected to the electret dielectric 3 charging process by applying a DC voltage of 4 kV for 1 hour between the center electrode 41 and the external electrode 43 at room temperature. Regarding the polarity of the DC voltage, the case where the central electrode side was the negative electrode and the external electrode side was the positive electrode was evaluated, but the opposite result was also obtained.

Example 4
Example 4 is substantially the same as Example 3, but without the electret dielectric 3 being extruded, a foamed polypropylene insulating tape (thickness: about 100 μm, width: about 5 mm) is spirally wrapped in multiple layers. Thus, an electret dielectric 3 having a thickness of about 1 mm was formed. Other configurations and charging methods are the same as those in the third embodiment.

(Comparative Example 5)
Comparative Example 5 is substantially the same as Example 3, but the electret dielectric 3 was provided on the center electrode 41 by extruding and covering polypropylene that is not a porous material. Other configurations are the same as those of the third embodiment.

(Comparative Example 6)
Comparative Example 6 is substantially the same as Example 4, except that a polypropylene insulating tape (thickness: about 100 μm, width: about 5 mm) that is not a porous material is spirally wrapped in multiple layers as the electret dielectric 3. Thus, an electret dielectric 3 having a thickness of about 1 mm was formed. Other configurations and the charging method are the same as those in the fourth embodiment.

FIG. 14 shows the vibration power generators of Examples 3 to 4 and Comparative Examples 5 to 6, with the vibration power generators sandwiched between two rigid plates and the same from the outside of the two plates. The evaluation result of the power generation output voltage when the vibration (vibration frequency is 1 Hz) is given. In addition, as a power generation output voltage, the power generation output voltage of the vibration power generation body of Example 3 is set to 1, and the normalized relative power generation output voltage is shown.

As shown in FIG. 14, Examples 3 and 4 using a porous material as the material of the electret dielectric 3 showed a relatively high power generation output voltage compared to Comparative Examples 5 and 6 using no porous material. . That is, the power generation output voltage is improved by making the electret dielectric 3 easier to deform.

Here, the reason why the power generation output voltage of Comparative Examples 5 and 6 is extremely small is that the electret dielectric 3 is not easily deformed compared to Examples 3 and 4, and the electret dielectric 3 has a very small charge amount. It is possible. That is, charging is performed by applying a DC voltage of 4 kV between the center electrode and the external electrode of the vibration power generator. In Comparative Examples 5 and 6, the applied DC voltage is applied to the electret dielectric 3. It seems that it is not enough to charge.

That is, when the electret dielectric 3 is made of a porous material, the applied voltage is sufficient to generate air discharge in the air holes even with an applied voltage of about 4 kV, so that the electret dielectric 3 is sufficiently charged. It is possible to make it. On the other hand, it is presumed that it was difficult to sufficiently charge the electret dielectric 3 having no voids inside at a DC voltage of 4 kV. That is, by using a porous material for the electret dielectric 3, it is possible to reduce the voltage of the charging process. Moreover, in the comparative example 6, although the insulating tape which is not a porous material is used as the electret dielectric material 3, since the electret dielectric material 3 is formed by wrapping the insulating tape in multiple layers, FIG. A gap 6 as shown in FIG. However, as can be seen from a comparison between Example 3 and Example 4, Example 4 in which the gap 6 as shown in FIG. 10A exists inside the electret dielectric has such a gap 6 present. The reason why the power generation output voltage of Examples 3 and 4 is remarkably higher than that of Comparative Examples 5 and 6 is that although the power generation output voltage is slightly higher than that of Example 3, This is considered to be because the quality electret dielectric 3 is used. Therefore, compared with Comparative Example 5, the power generation output voltage is slightly higher in Comparative Example 6 in which the gap 6 as shown in FIG. 10A exists in the electret dielectric, but compared with Examples 3 and 4. Then, as described above, it is considered that the power generation output voltage is considerably lowered because the electret dielectric 3 is not sufficiently charged.

(Example 5)
Next, with respect to the vibration power generation body shown in the vibration power generation body 40 (FIG. 5), the vibration power generation body subjected to another electret dielectric 3 charging method and manufacturing method of the vibration power generation body was evaluated. The configuration and structure of the vibration power generator of Example 5 are substantially the same as those of Example 3. In Example 5, after the foamed polypropylene is extruded as the electret dielectric 3 on the center electrode 41, the surface potential of the foamed polypropylene is set to −4 kV (by a corona discharge device disposed with a gap around the outer periphery of the foamed polypropylene. The electret dielectric 3 was formed by approximately uniformly charging the potential of the center electrode to the reference). Thereafter, a tin-plated copper braided wire as the external electrode 43 and polyvinyl chloride as the covering portion 45 were sequentially coated to complete the vibration power generator.

(Example 6)
Example 6 is substantially the same as Example 5, but without the electret dielectric 3 being extruded, a foamed polypropylene insulating tape (thickness: about 100 μm, width: about 5 mm) is spirally wrapped in multiple layers. Thus, an electret dielectric 3 having a thickness of about 1 mm was formed. Other configurations, the electret dielectric charging method, and the vibration power generator manufacturing method are the same as in the fifth embodiment.

(Comparative Example 7)
Comparative Example 7 is substantially the same as Example 5, except that polypropylene, which is not a porous material, is extruded and coated on the center electrode 41 as the electret dielectric 3. Other configurations, the electret dielectric 3 charging method, and the vibration power generator manufacturing method are the same as in the fifth embodiment.

(Comparative Example 8)
Comparative Example 8 is substantially the same as Example 6, but as the electret dielectric 3, a polypropylene insulating tape (thickness: about 100 μm, width: about 5 mm) that is not a porous material is spirally wrapped in multiple layers. Thus, an electret dielectric 3 having a thickness of about 1 mm was formed. Other configurations, the electret dielectric 3 charging method, and the vibration power generator manufacturing method are the same as those in the sixth embodiment.

FIG. 15 shows the vibration power generators of Examples 5 to 6 and Comparative Examples 7 to 8, with the vibration power generators sandwiched between two rigid plates and the same from the outside of the two plates. The evaluation result of the power generation output voltage when the vibration (vibration frequency is 1 Hz) is given. In addition, as a power generation output voltage, the power generation output voltage of the vibration power generation body of Example 5 is set to 1, and a normalized relative power generation output voltage is shown.

As described above, the electret dielectrics 3 in Examples 5 and 6 and Comparative Examples 7 and 8 are all charged so as to have the same surface potential, but the electret dielectric 3 is made of a porous material. In Examples 5 and 6 using, the power generation output voltage was relatively high compared to Comparative Examples 7 and 8 in which no porous material was used. That is, the power generation output voltage is improved by making the electret dielectric 3 easier to deform.

As described above, as is clear from a comparison between Example 5 in which the electret dielectric 3 is extrusion-molded and Example 6 in which the electret dielectric 3 is formed with an insulating tape, it is more efficient to form the electret dielectric 3 with the insulating tape. Although the output voltage tends to be high, the difference is small. That is, in consideration of the manufacturability of the vibration power generator, which configuration is to be set may be appropriately set.

Further, Example 3 and Example 5, Example 4 and Example 6, Comparative Example 5 and Comparative Example 7, and Comparative Example 6 and Comparative Example 8 have the same configuration and structure of the vibration power generator, respectively. The charging method of the dielectric 3 and the method of manufacturing the vibration power generator are different. Here, when the power generation output voltage of each vibration power generation body in FIGS. 14 and 15 is compared, although the configuration and structure of the vibration power generation body are the same, Comparative Example 5 and Comparison with Example 3 and Example 4 are compared. The ratio of the power generation output voltage of Example 6 is considerably smaller than the ratio of the power generation output voltage of Comparative Example 7 and Comparative Example 8 to Example 5 and Example 6. This is one of the reasons that the electret dielectric 3 in Comparative Example 5 and Comparative Example 6 is not sufficiently charged as described above. The reason why the electret dielectric 3 is insufficiently charged is considered to be caused by a difference between the electret dielectric 3 charging method and the vibration power generator manufacturing method. That is, when the electret is charged by applying a voltage between a pair of electrodes sandwiching the electret dielectric 3 as a final step of the vibration power generator (Examples 3 and 4, Comparative Examples 5 and 6), The electret dielectric can be charged with a relatively low voltage (DC voltage or AC voltage). On the other hand, the electret dielectric 3 that is not porous needs to be charged at a relatively high voltage. Therefore, when both electret dielectrics 3 are charged with the same voltage value, there is a possibility that insufficient electrification with non-porous electret dielectrics will occur. On the other hand, when electret dielectrics are charged as an intermediate step in the manufacturing process of the vibration power generator (Examples 5 and 6, Comparative Examples 7 and 8), the corona discharge generator provided externally forcibly Since the surface potential of the electret dielectric 3 can be adjusted, the electret dielectric 3 is not insufficiently charged. Although there are advantages and disadvantages in both the electret dielectric 3 charging method and the vibration power generator manufacturing method, the electret dielectric 3 is applied by applying a voltage between the electrodes of the vibration power generator in the final step of the vibration power generator manufacturing process. This charging method is highly convenient in that it is not necessary to provide a large-scale corona discharge generator outside and in terms of quality control in the manufacturing process of the vibration power generator. And it becomes easy to employ | adopt the manufacturing method of such a vibration electric power generation body by using the porous electret dielectric material 3 for a vibration electric power generation body.

As described above, a high power generation output voltage can be obtained by using the electret dielectric 3 that is a porous material.

As described above, according to the present invention, it is possible to obtain a vibration power generator that can be easily charged, has excellent flexibility and free workability, and can easily be increased in area. As the vibration power generation body of the present invention, for example, it can be installed on an object that vibrates when a vehicle such as a sound barrier, a railroad rail or a sleeper installed under a road, a bridge, or a highway passes. it can. At this time, the obtained electric power senses the surrounding conditions (temperature, humidity, brightness, vibration acceleration, distortion, displacement, wind speed, vehicle speed and weight, etc.) of the vibration object, and drives the sensor for measurement. Can be made. Further, it can be used as a power source for an information collecting system or a monitoring system that transmits information obtained by a sensor by wire or wireless.

Also, when the power obtained is large, it can also be used as one of distributed power sources for lighting such as roads, auxiliary power sources for traffic lights, and smart grid concepts. In addition, on a road or the like, power may be generated by vibration when a vehicle or a person passes, thereby sensing information that the vehicle or person has passed and ambient brightness. In this case, only when the surroundings are dark, the stored power can be used to light the front of the vehicle or person, the guide plate, the guide light, and the like.

Also, the vibration power generator of the present invention can itself be used as a sensor for detecting a change in external force such as vibration. For example, it can be used in a security system in which a vibration power generator is installed in a site, a passage or the like, and power is generated by vibration when a suspicious person invades, thereby transmitting suspicious person intrusion information.

Also, the present invention can be applied to a moving body that itself vibrates, such as a vehicle, an aircraft, a person, or an animal. For example, a vibration power generator or a vibration power generator cable may be installed in a car body, a suspension, a tire (such as the inside of a tire, a rubber inner surface, or a wheel portion) of an automobile, and various sensors may be driven by the generated power. Moreover, when the electric power obtained is large, it can also be used as a power source for auxiliary charging to a secondary battery of an automobile. Similarly, it is applied to the body of a railway vehicle, the inside of a vehicle, wheels, dampers, suspensions, etc., and power for systems that monitor various parts of the vehicle by driving various sensors, interior lighting, emergency lights, advertising displays It can also be used as an (auxiliary) power source for panels and the like.

As a system sensor and power supply, a vibration power generator is installed in the seat of a vehicle, etc., and when a person is seated or generated by vibration during seating, it detects the person's seating and informs the driver's seat or cockpit. It can also be used.

Also, a vibration power generator or a vibration power cable can be applied to a building structure such as a building, factory, or house, or a structure included in a building structure. For example, the above-mentioned building structure includes the vibration of the ground, the influence of wind, the movement of people inside, the mechanical devices installed inside (for example, rotating machines such as motors, production equipment in factories, elevators and escalators, etc. In response to vibration when an elevator, an air conditioning fan, etc.) are operating, it itself vibrates. Therefore, it is possible to install a vibration power generator in a site that is susceptible to such vibration and generate electric power, and use it as a driving power source such as an emergency power source, various sensors, or a communication power source.

Also, the vibration power generator of the present invention can be applied to portable electronic devices such as personal computers, mobile phones, and remote controllers, and input devices such as touch panels, keyboards, and push buttons. For example, a vibration power generator is installed in the casing of a portable electronic device such as a personal computer or a mobile phone, and the power is generated by vibration during transportation or use of the device and used as an auxiliary charging power source for a secondary battery. You can also. It can also be used as a power source for a system that generates power by vibration of an input device and transmits input information to a master station or the like.

The embodiment of the present invention has been described above with reference to the accompanying drawings, but the technical scope of the present invention is not affected by the above-described embodiment. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

1, 1a, 30, 40, 40a, 40b ......... Vibration generator 3 ......... Electret dielectric 4 ...... Hole 5a, 5b, 31a, 31b ......... Electrode 6 ...... Gap 7 ......... Spacer 9 ......... Non-joint part 11 ... Contact part 33 ... Conductor layer 35 ... Resin layer 41 ... Center electrode 43 ... External electrode 45 ... Cover part 47 ... Space 49 ......... Elastic body 51 ......... Resin tape 60 ......... Vibration power generator 61 ......... Diode 63 ......... Power storage unit 65 ......... Switch 67 ......... Rectifier circuit 69 ......... Power storage circuit

Claims

A pair of electrodes;
An electret dielectric that is provided between the pair of electrodes and retains a charge;
Comprising
The electret dielectric is a flexible material composed of a porous material having pores inside.
A vibration power generator, wherein when an external force is applied, a distance between at least one of the pair of electrodes and the electret dielectric can be changed at least in part.
Between at least one of the electrodes and the electret dielectric, a non-joined portion that is not joined to each other is formed,
The vibration power generator according to claim 1, wherein when an external force is applied, a distance between the electret dielectric and at least one of the electrodes is changeable in at least a part of the non-joining portion.
A spacer is partially provided between the electret dielectric and at least one of the electrodes, and the electret dielectric and the electrode are joined via at least a part of the spacer, and other than the spacer The vibration power generator according to claim 2, wherein a part is the non-joining part.
One of the pair of electrodes is a center electrode, the other is an external electrode,
The electret dielectric is provided on the outer periphery of the center electrode, and the external electrode is provided on the outer periphery of the electret dielectric,
The vibration power generator according to claim 1, wherein an outer periphery of the external electrode is covered with a covering portion.
A method of manufacturing a vibration power generator,
A pair of electrodes, and an electret dielectric that is a porous material provided between the pair of electrodes and having pores therein, and between at least one of the electrodes and the electret dielectric Using non-bonded portions that are not bonded to each other, using a vibration power generation body before charging treatment having a gap in at least a part of the non-bonded portions,
A method of manufacturing a vibration power generator, wherein a voltage is applied between the pair of electrodes to cause discharge in the voids or in the gaps, thereby charging the electret dielectric.