JP2018191481A - Oscillation power generation element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oscillation power generation element capable of improving a power generation amount.SOLUTION: An oscillation power generation element comprises: a first electrode (11) which is supported by a cantilever structure that one end (E1) is fixed to a stator part (17), and the other end (E2) is a free end; a second electrode (14) that is opposite to the first electrode, and is supported by the cantilever structure that the one end (E3) is fixed to the stator part (17), and the other end (E4) is a free end; an electret (12) arranged between the first electrode and the second electrode; an insulation layer (13) arranged between the first electrode and the second electrode; and a stopper (16) that peels off the second electrode contacted to the first electrode through the electret and the insulation layer from the first electrode by regulating a movement of the first electrode oriented to the second electrode side.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vibration power generation element using an electret.

  In recent years, a vibration power generation element that generates power using vibration energy has been developed (see, for example, Non-Patent Document 1).

  Non-Patent Document 1 discloses a vibration power generation element that generates power by vibrating a plate-like upper electrode provided with a dielectric and a plate-like lower electrode provided with an electret in the vertical direction. In the vibration power generation element of Non-Patent Document 1, the upper electrode and the lower electrode generate power by repeating surface contact and peeling through a dielectric and an electret.

  Moreover, as a technique for generating power using vibration energy, for example, Patent Document 1 and Patent Document 2 can be cited.

JP 2014-107982 A Japanese Patent Laying-Open No. 2005-0665463

Tomokazu Takahashi, Masato Suzuki, Toshio Nishida, Yasuhiro Yoshikawa, Seiji Aoyagi “VERTICAL CAPACITIVE ENERGY HARVESTER POSITIVELY USING CONTACT BETWEEN PROOF MASS AND ELECTRET PLATE -STIFFNESS MACTHING BY SPRING SUPPORT OF PLATE AND STICTION PRESTION BYISSTOPECEC, PORTUGAL, 15-22 January, 2015, p.1145-1148

  However, the vibration power generation element listed in Non-Patent Document 1 has room for improvement in terms of improving the power generation amount.

  An object of this invention is to provide the vibration electric power generation element which can improve the electric power generation amount.

The vibration power generation element of one embodiment of the present invention is
A first electrode supported by a cantilever structure in which one end is fixed to a fixed portion and the other end is a free end;
A second electrode supported by a cantilever structure facing the first electrode, having one end fixed to the fixing portion and the other end being a free end;
An electret disposed between the first electrode and the second electrode;
An insulating layer disposed between the first electrode and the second electrode;
The second electrode that is in contact with the first electrode via the electret and the insulating layer is peeled off from the first electrode by restricting the movement of the first electrode toward the second electrode. A stopper to
Is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the vibration electric power generation element which can improve electric power generation amount can be provided.

It is a perspective view of the vibration electric power generation element of embodiment which concerns on this invention. It is side surface sectional drawing of the vibration electric power generation element of embodiment which concerns on this invention. It is a top view of the vibration electric power generation element of embodiment which concerns on this invention. It is a perspective view which shows an example of operation | movement of the vibration electric power generation element of embodiment which concerns on this invention. It is side surface sectional drawing which shows an example of operation | movement of the vibration electric power generation element of embodiment which concerns on this invention. It is a perspective view which shows an example of operation | movement of the vibration electric power generation element of embodiment which concerns on this invention. It is side surface sectional drawing which shows an example of operation | movement of the vibration electric power generation element of embodiment which concerns on this invention. It is a figure which shows an example of the relationship between the position of the electrode and output voltage in the vibration electric power generation element of embodiment which concerns on this invention. It is a figure which shows an example of the peeling condition of the 1st electrode and 2nd electrode at the time of dividing | segmenting the vibration electric power generation element of embodiment which concerns on this invention into a some area. It is a figure which shows the example of the waveform of the output voltage in each area shown to FIG. 7A. It is a figure which shows schematic structure of the 2nd electrode of a modification. It is a figure which shows the comparison result of the output voltage and the instantaneous electric power of Example 1 and the comparative example 1 of the vibration electric power generation element of embodiment which concerns on this invention. It is a figure which shows the comparison result of the electric power generation amount of Example 2 and Comparative Examples 2-5 of the vibration electric power generation element of embodiment which concerns on this invention.

(Background to the present invention)
In recent years, vibration power generation elements that generate power using vibration energy (kinetic energy) have been developed. For example, in Non-Patent Document 1, a plate-like upper electrode and a lower electrode arranged facing each other vibrate in the vertical direction (thickness direction), and surface contact and peeling are repeated through a dielectric and an electret. A vibration power generation element for generating power is disclosed.

  Patent Document 1 discloses a power generation device that suppresses the amplitude of a vibration part supported by a support part so as to be able to vibrate with a vibration suppressing member in order to realize a stable output. Further, cited reference 2 discloses a vibrator for vibration power generation provided with a stopper for preventing one electrode from coming into contact with the other electrode and short-circuiting.

  However, in Non-Patent Document 1, since the plate-like upper electrode and lower electrode in surface contact are peeled off in the thickness direction, the two electrodes are difficult to peel off. In Patent Documents 1 and 2, a stopper is used to suppress an excessive amplitude of the vibrator. For this reason, in Non-patent Document 1, Patent Documents 1 and 2, there is a problem that loss of kinetic energy occurs and power generation cannot be improved.

  Therefore, the present inventors have arrived at the following invention in order to solve the above problems.

The vibration power generation element of one embodiment of the present invention is
A first electrode supported by a cantilever structure in which one end is fixed to a fixed portion and the other end is a free end;
A second electrode supported by a cantilever structure facing the first electrode, having one end fixed to the fixing portion and the other end being a free end;
An electret disposed between the first electrode and the second electrode;
An insulating layer disposed between the first electrode and the second electrode;
The second electrode that is in contact with the first electrode via the electret and the insulating layer is peeled off from the first electrode by restricting the movement of the first electrode toward the second electrode. A stopper to
Is provided.

  With such a configuration, the second electrode that is in contact with the first electrode via the electret and the insulating layer can be peeled off from the first electrode, so that loss of kinetic energy is suppressed and power generation is improved. Can be made.

  The stopper may peel off the second electrode from the first electrode starting from the other end of the second electrode.

  With such a configuration, since the second electrode can be peeled off from the first electrode starting from the other end (free end) of the second electrode, the loss of kinetic energy is suppressed and the power generation amount is further improved. Can do.

  The electret may be in contact with either the first electrode or the second electrode.

  With such a configuration, the first electrode or the second electrode on which the electret is disposed and the electret can be maintained in contact with each other without being peeled off. For this reason, it can suppress that the electric power stored in the electret 12 discharges toward the 1st electrode or the 2nd electrode by the side where the electret is arrange | positioned, and electric power generation amount falls.

  The stopper may be disposed inside a movable range of the other end of the second electrode in a direction in which the first electrode and the second electrode face each other.

  With such a configuration, the second electrode can be more easily separated from the first electrode by the stopper.

  The area of the surface of the second electrode on the side facing the first electrode may be smaller than the area of the surface of the first electrode on the side facing the second electrode.

  With such a configuration, the electrostatic attractive force can be lowered, and the second electrode can be more easily separated from the first electrode.

  The stopper may be disposed at a position that overlaps the first electrode instead of overlapping the second electrode when viewed from the direction in which the first electrode and the second electrode face each other.

  With such a configuration, the second electrode can be more easily separated from the first electrode.

  The stopper may be arranged along a direction extending from one end of the first electrode toward the other end.

  With such a configuration, the second electrode can be stably peeled off from the first electrode. For this reason, the loss of kinetic energy can be reduced and the amount of power generation can be further improved.

  Furthermore, you may provide the weight provided in the said 2nd electrode.

  With such a configuration, kinetic energy can be improved and the amount of power generation can be improved.

  The weight may be provided at the other end of the second electrode.

  With such a configuration, kinetic energy can be further improved, and the amount of power generation can be further improved.

  The second electrode may have a plurality of electrode portions connected at one end and supported by a cantilever structure having the other end as a free end.

  With such a configuration, power generation can be performed according to various frequency bands.

  Hereinafter, embodiments according to the present invention will be described with reference to the accompanying drawings. In each drawing, each element is exaggerated for easy explanation.

(Embodiment)
A vibration power generation element according to an embodiment of the present invention will be described.

[overall structure]
FIG. 1 is a perspective view of a vibration power generation element 10 according to an embodiment of the present invention. FIG. 2 is a side sectional view of the vibration power generation element 10. FIG. 3 is a plan view of the vibration power generation element 10. 1 to 3 indicate the longitudinal direction, the lateral direction, and the thickness direction of the vibration power generation element 10, respectively. Moreover, FIGS. 1-3 has shown the schematic of the vibration electric power generation element 10 when the external vibration is not applied. 1-3 show an example of the vibration power generation element 10, and the configuration of the vibration power generation element 10 is not limited to these.

  As shown in FIGS. 1 to 3, the vibration power generation element 10 includes a first electrode 11, an electret 12, an insulating layer 13, a second electrode 14, a weight 15, and a stopper 16. The vibration power generation element 10 has a double cantilever structure in which one end of the first electrode 11 and the second electrode 14 is fixed to the fixing portion 17 via the electret 12 and the insulating layer 13.

<First electrode>
As shown in FIG. 2, the first electrode 11 is supported by a cantilever structure in which one end E1 is fixed to the fixing portion 17 and the other end E2 is a free end. The first electrode 11 is formed of a plate-like member that extends from the fixed portion 17 in the Y direction. The first electrode 11 is made of an elastically deformable material. The 1st electrode 11 can be formed with materials, such as copper, aluminum, iron, platinum, or those alloys, for example. In the embodiment, the first electrode 11 is formed of a rectangular copper plate from the viewpoint of ease of processing and cost.

<Electret>
The electret 12 is a member that holds a charge semipermanently. Specifically, the electret 12 is formed in a plate shape and is a member that can be elastically deformed. As the electret 12, an organic electret in which a charge is held in a polymer compound such as Cytop (registered trademark) may be used. Alternatively, an inorganic electret in which a charge is held on a base material such as silicon oxide (SiO ₂ ) or silicon nitride (SiN) may be used.

  The electret 12 is disposed between the first electrode 11 and the second electrode 14. Specifically, the electret 12 is disposed on the first electrode 11 and is disposed on the surface of the first electrode 11 on the side where the second electrode 14 is disposed. In the embodiment, the electret 12 covers the surface of the first electrode 11 on the side where the second electrode 14 is disposed. By adopting a configuration in which the surface of the first electrode 11 on the side where the second electrode 14 is disposed is not exposed, the charge outflow to the exposed first electrode 11 can be suppressed during the charge injection into the electret 12. Thereby, the charge injection efficiency to the electret 12 can be improved.

<Insulating layer>
The insulating layer 13 is an insulating member disposed between the first electrode 11 and the second electrode 14. In the embodiment, the insulating layer 13 is disposed between the electret 12 and the second electrode 14. The insulating layer 13 is formed in a plate shape or a film shape, and covers the surface of the second electrode 14 on the side where the first electrode 11 is disposed. In addition, the thickness of the insulating layer 13 can be made thinner than the thickness of the first electrode 11 and the second electrode 14 as long as dielectric breakdown does not occur. By reducing the thickness of the insulating layer 13, the amount of charge transfer can be increased, so that the amount of power generation can be improved. The insulating layer 13 is formed according to the shape of the second electrode 14.

  The insulating layer 13 is formed of an insulating material that can be elastically deformed. The insulating layer 13 can be formed of a material such as an epoxy resin, a silicon oxide film, vinyl chloride, nylon, or polyester.

<Second electrode>
The second electrode 14 is supported by a cantilever structure that faces the first electrode 11 with the electret 12 and the insulating layer 13 interposed therebetween, fixes one end E3 to the fixing portion 17, and has the other end E4 as a free end. Yes. The second electrode 14 is formed of a plate-like member that extends from the fixed portion 17 in the Y direction. The second electrode 14 is made of an elastically deformable material. The 2nd electrode 14 can be formed with materials, such as copper, aluminum, iron, platinum, or those alloys, for example. In the embodiment, from the viewpoint of ease of processing and cost, the second electrode 14 is formed of a rectangular copper plate, like the first electrode 11.

  The area of the surface of the second electrode 14 facing the first electrode 11 is smaller than the area of the surface of the first electrode 11 facing the second electrode 14.

<Weight>
The weight 15 is a member that increases the kinetic energy of the second electrode 14 that vibrates in response to external vibration. The weight 15 is provided on the second electrode 14. Specifically, as shown in FIG. 2, the weight 15 is provided at the other end E <b> 4 of the second electrode 14.

<Stopper>
The stopper 16 is a member that regulates the movement of the first electrode 11 toward the second electrode 14 that is performed by external vibration. Specifically, the stopper 16 restricts the movement in the Z direction between the first electrode 11 and the electret 12 that move toward the side where the second electrode 14 is disposed. Thereby, the second electrode 14 in contact with the first electrode 11 can be peeled off from the first electrode 11 with the other end E4 of the second electrode 14 as a starting point. That is, the second electrode 14 that is in contact with the first electrode 11 can be gradually peeled from the first electrode 11 from the other end E4 to the one end E3 of the second electrode 14 by the stopper 16. In the embodiment, the stopper 16 separates the second electrode 14 and the insulating layer 13 from the first electrode 11 and the electret 12.

  The stopper 16 is formed of, for example, two rigid bodies formed in a plate shape. The stopper 16 can be formed of a material such as a polymer such as an acrylic resin, fiber, glass, rubber, or a composite material thereof.

  As shown in FIG. 2, the stopper 16 is disposed along the direction extending from one end E1 to the other end E2 of the first electrode 11, that is, the Y direction. As shown in FIG. 3, the stopper 16 does not overlap the second electrode 14 when viewed from the direction in which the first electrode 11 and the second electrode 14 face each other, that is, when viewed from the Z direction. 11 is arranged so as to overlap.

  The stopper 16 is disposed in the direction in which the first electrode 11 and the second electrode 14 face each other, that is, inside the movable range of the other end E4 of the second electrode 14 in the Z direction. In other words, the stopper 16 is disposed inside the amplitude in the Z direction of the other end E4 of the second electrode 14 that vibrates in response to external vibration.

  In the embodiment, one end of the first electrode 11, electret 12, insulating layer 13, and second electrode 14 is formed longer in the X direction than the other end in order to improve the fixing strength.

[Operation]
The operation of the vibration power generation element 10 will be described.

  FIG. 4A is a perspective view illustrating an example of the operation of the vibration power generation element 10. FIG. 4B is a side sectional view showing an example of the operation of the vibration power generation element 10. FIG. 5A is a perspective view illustrating an example of the operation of the vibration power generation element 10. FIG. 5B is a side sectional view showing an example of the operation of the vibration power generation element 10. In FIG. 4A and FIG. 5A, illustration of the fixing portion 17 is omitted for ease of explanation.

  4A, 4B, 5A, and 5B, one end E1 of the first electrode 11 is connected to the ground terminal via a load 18. One end E3 of the second electrode 14 is directly connected to the ground terminal. The load 18 is a load for taking out a current flowing between the first electrode 11 and the ground terminal as a voltage. For example, a resistor or a capacitor can be used as the load 18.

  4A and 4B show a first state in which the other end E2 of the first electrode 11 and the other end E4 of the second electrode 14 are moved below the stopper 16 when subjected to external vibration. ing. As shown in FIGS. 4A and 4B, in the first state, the second electrode 14 is in contact with the first electrode 11 via the electret 12 and the insulating layer 13. In the first state, a current flows from the first electrode 11 to the ground terminal via the load 18 (see arrow 21 in FIG. 4A).

  5A and 5B show a second state in which the other end E4 of the second electrode 14 moves above the stopper 16 when subjected to external vibration. As shown in FIGS. 5A and 5B, in the second state, the movement of the first electrode 11 and the electret 12 toward the second electrode 14 is restricted by the stopper 16. As a result, the second electrode 14 gradually peels from the first electrode 11 from the other end E4 of the second electrode 14 toward the one end E3. In other words, the other end E4 of the second electrode 14 is peeled off so as to be turned up from the other end E2 of the first electrode 11. In the second state, a current flows from the ground end to the first electrode 11 via the load 18 (see arrow 22 in FIG. 4B).

  As described above, in the vibration power generation element 10, the second electrode 14 comes into contact with the first electrode 11 through the electret 12 and the insulating layer 13 when receiving external vibration. In the vibration power generation element 10, the other end E <b> 4 of the second electrode 14 is peeled off so as to be turned up from the other end E <b> 2 of the first electrode 11. As described above, the vibration power generation element 10 generates power by repeating contact and peeling between the first electrode 11 and the second electrode 14.

<Relationship between electrode position and output voltage>
FIG. 6 shows an example of the relationship between the electrode position and the output voltage in the vibration power generation element 10. In FIG. 6, the symbol “Tp” indicates the position of the stopper 16 in the Z direction.

As shown in FIG. 6, the first electrode 11 and the second electrode 14 are at a position lower than the position Tp of the stopper 16 during the time t _{1 to} t ₂ . From time t _{1 to} t ₂ , the second electrode E2 and the other electrode E4 of the second electrode 14 are in contact with each other and move toward the stopper 16.

At time _{t 2,} the other end E2 of the first electrode 11 and the other end E4 of the second electrode 14 reaches the position Tp of the stopper 16, the other end E4 of the second electrode 14 is the other end of the first electrode E2 Peel from. At time t _2, the output voltage is rapidly lowered. Thereafter, as the other end E4 of the second electrode 14 is peeled off from the first electrode 11, the output voltage increases.

From time t _{3 to} t ₅ , the other end E 4 of the second electrode 14 moves toward the first electrode 11, and again reaches the other end E 2 of the first electrode 11 through the electret 12 and the insulating layer 13. Contact. From time t _{3 to} t ₅ , the output voltage gradually decreases.

  FIG. 7A is a diagram illustrating an example of a peeling state between the first electrode 11 and the second electrode 14 when the vibration power generation element 10 is divided into a plurality of sections D1-D5. FIG. 7B shows an example of the waveform of the output voltage in the plurality of sections shown in FIG. 7A. 7A and 7B show an example of the peeling state when the other end E4 of the second electrode 14 is farthest from the other end E2 of the first electrode 11. FIG. The section D1-D5 is a section obtained by dividing a part where peeling occurs from one end E3 to the other end E4 of the second electrode 14 into five. Moreover, in FIG. 7A and FIG. 7B, the image figure of the peeling condition of each area is shown so that the peeling condition of the 2nd electrode 14 and the 1st electrode 11 in area D1-D5 can be compared easily.

  As shown in FIG. 7A, the other end E4 of the second electrode 14 is peeled off from the other end E2 of the first electrode 11, so that the second electrode 14 and the second electrode 14 are arranged in the order of sections D1, D2, D3, D4, and D5. The distance (peeling amount) from the first electrode 11 is large. In other words, the distance (peeling amount) between the second electrode 14 and the first electrode 11 increases as the distance from the one end E3 to the other end E4 of the second electrode 14 increases.

  As shown in FIG. 7B, the time during which the output voltage can be extracted is longer in the order of sections D1, D2, D3, D4, and D5. This is because, after the second electrode 14 is peeled from the first electrode 11, the second electrode 14 passes through the electret 12 and the insulating layer 13 in the order of the sections D1, D2, D3, D4, and D5. It is because it contacts 11. That is, the time during which the second electrode 14 is peeled from the first electrode 11 increases in the order of the sections D1, D2, D3, D4, and D5. For this reason, the time during which the output voltage can be extracted in the order of the sections D1, D2, D3, D4, and D5 becomes longer.

  As shown in FIG. 7B, the waveform of the output voltage of the entire vibration power generation element 10 is obtained by adding the output waveforms of the sections D1-D5.

[effect]
According to the vibration power generation element 10 according to the embodiment, the following effects can be obtained.

  According to the vibration power generation element 10, the first electrode 11 can be peeled off by the stopper 16 so that the second electrode 14 is turned up from the first electrode 11 starting from the other end E4 of the second electrode 14. The electrostatic attraction between the first electrode 14 and the second electrode 14 can be reduced. Thereby, since the 2nd electrode 14 can be easily peeled from the 1st electrode 11, the loss of a kinetic energy can be suppressed and the electric power generation amount can be improved.

  According to the vibration power generation element 10, since the electrostatic attractive force between the first electrode 11 and the second electrode 14 can be reduced, the electret 12 having a high surface potential can be used. Thereby, the electric power generation amount can be further improved.

  According to the vibration power generation element 10, power generation can be performed with a simple structure. In addition, the parts constituting the vibration power generation element 10 can be easily processed, and the cost can be reduced. Furthermore, there is a merit that there are many choices of materials constituting the vibration power generation element 10.

  The stopper 16 is disposed inside the movable range of the other end E4 of the second electrode 14 in the direction in which the first electrode 11 and the second electrode 14 face each other, that is, in the Z direction. With such a configuration, the second electrode 14 can be easily separated from the first electrode 11.

  The area of the surface of the second electrode 14 on the side facing the first electrode 11 is smaller than the area of the surface of the first electrode 11 on the side facing the second electrode 14. With such a configuration, since the electrostatic attractive force between the first electrode 11 and the second electrode 14 can be reduced, the second electrode 14 can be easily separated from the first electrode 11.

  The stopper 16 is disposed not at the second electrode 14 but at the position overlapping the first electrode 11 when viewed from the direction in which the first electrode 11 and the second electrode 14 face each other, that is, from the Z direction. With such a configuration, the second electrode 14 can be more easily separated from the first electrode 11.

  The stopper 16 is disposed along the direction extending from one end E1 to the other end E2 of the first electrode 11, that is, the Y direction. With such a configuration, the other end E4 of the second electrode 14 can be gradually separated from the first electrode 11 from the other end E4 of the second electrode 14 toward the one end E3. For this reason, since the other end E4 of the 2nd electrode 14 can be stably peeled from the 1st electrode 11, the loss of a kinetic energy can further be suppressed.

  In the vibration power generation element 10, a weight 15 is provided on the second electrode 14. With such a configuration, kinetic energy can be increased and the amount of power generation can be improved. Moreover, by providing the weight 15 at the other end E4 of the second electrode 14, the kinetic energy can be further increased, and the amount of power generation can be further improved.

  The vibration power generation element 10 can be attached in various directions such as a vertical direction, a horizontal direction, and an oblique direction.

  Such a vibration power generation element 10 can constitute a power generation device by being incorporated in a circuit or the like, for example. For this reason, the electric power generating apparatus which has the effect of the vibration electric power generation element 10 mentioned above can be provided.

  In the embodiment, the example in which the first electrode 11 and the second electrode 14 are formed of the same material has been described. However, the present invention is not limited to this. For example, the first electrode 11 and the second electrode 14 may be formed of different materials.

  In the embodiment, the example in which the insulating layer 13 covers the surface of the second electrode 14 on the side facing the first electrode 11 has been described, but the embodiment is not limited thereto. The insulating layer 13 only needs to insulate between the second electrode 14 and the electret 12, and may be formed on the electret 12 side, for example.

  In the embodiment, the example in which the electret 12 is disposed on the first electrode 11 and the insulating layer 13 is disposed on the second electrode 14 has been described. However, the present invention is not limited to this. For example, the electret 12 may be disposed on the second electrode 14 and the insulating layer 13 may be disposed on the first electrode 11.

  In the embodiment, the stopper 16 is described as an example in which the second electrode 14 and the insulating layer 13 are peeled off, but the present invention is not limited to this. For example, the stopper 16 may peel only the second electrode 14.

  In the first embodiment, it is preferable that the second electrode 14, the insulating layer 13, and the electret 12 are not separated from the first electrode 11. When the electret 12 is peeled from the first electrode 11, the electric charge stored in the electret 12 is discharged toward the first electrode 11, so that the amount of power generation may be reduced. For this reason, it is preferable to maintain the state which the 1st electrode 11 in which the electret 12 is arrange | positioned, and the electret 12 do not peel. With such a configuration, it is possible to suppress a decrease in the amount of power generated due to the electric charge stored in the electret 12 being discharged toward the first electrode 11.

  When the electret 12 is disposed on the second electrode 14 and the insulating layer 13 is disposed on the first electrode 11, the second electrode 14 and the electret 12 are separated from the insulating layer 13 and the first electrode 11 by the stopper 16. It may be peeled off. In this case, it is preferable that the second electrode 14 and the electret 12 are peeled from the insulating layer 13 and the first electrode 11 in a state where they are in contact with each other. With such a configuration, it is possible to suppress a decrease in the amount of power generated due to the electric charge stored in the electret 12 being discharged toward the second electrode 14.

  In the embodiment, the stopper 16 has been described with respect to the example in which the stopper 16 is disposed along the direction extending from the one end E1 to the other end E2 of the first electrode 11, that is, the Y direction, but the present invention is not limited thereto. The stopper 16 turns the other end E4 of the second electrode 14 from the first electrode 11 by restricting the movement of the first electrode 11 toward the second electrode 14, that is, the movement of the first electrode 1 in the Z direction. What is necessary is just to be arrange | positioned in the position which can be made to peel so that it may raise. The stopper 16 may be arrange | positioned at the other end E2 of the 1st electrode 11, for example.

  In the embodiment, the example in which the weight 15 is provided at the other end E4 of the second electrode 14 has been described, but the embodiment is not limited thereto. For example, the weight 15 may be provided between one end E3 and the other end E4 of the second electrode 14. In the vibration power generation element 10, the weight 15 is for increasing kinetic energy and is not an essential component. For example, in the vibration power generation element 10, in order to increase the kinetic energy, the thickness of the other end E4 of the second electrode 14 is increased without using the weight 15, and the weight of the other end E4 is set to another part. You may enlarge compared.

  In embodiment, although the electret 12 and the insulating layer 13 demonstrated the example by which one end is fixed to the fixing | fixed part 17, it is not limited to this. The electret 12 and the insulating layer 13 may be disposed between the first electrode 11 and the second electrode 14 and may not be supported by the fixing portion 17.

  In the embodiment, the example in which the length in the X direction at one end of the first electrode 11, the electret 12, the insulating layer 13, and the second electrode 14 is made longer than that at the other end is not limited to this. For example, the length in the X direction of one end of the first electrode 11, electret 12, insulating layer 13, and second electrode 14 may be the same length as the other end or may be shorter than the other end.

  In the embodiment, the second electrode 14 is a flat electrode formed of a rectangular copper plate, but is not limited thereto. If it is desired to change the frequency band according to various external vibrations, the shape of the second electrode 14 may be changed. For example, in the vibration power generation element 10, when it is desired to change the corresponding external vibration frequency band, the dimension of the second electrode 14 may be changed. Alternatively, the second electrode 14 may be formed of a plurality of electrode portions in order to cope with multi-frequency external vibrations.

  FIG. 8 shows a schematic configuration of the second electrode 14a of the modification. As shown in FIG. 8, the second electrode 14a is connected at one end E3 and has a plurality of electrode portions 14aa, 14ab, 14ac supported by a cantilever structure with the other ends E4a, E4b, E4c as free ends. You may have. The plurality of electrode portions 14aa, 14ab, 14ac are formed of a plate-like member extending in the Y direction from one end E3 of the fixed second electrode 14a. Specifically, the plurality of electrode portions 14aa, 14ab, 14ac are formed in a flat plate shape.

  The plurality of electrode portions 14aa, 14ab, 14ac are connected at one end E3, and are supported in a cantilever structure having one end E3 as a fixed end and the other end E4a, E4b, E4c as a free end. Further, the plurality of electrode portions 14aa, 14ab, 14ac are arranged with an interval in the X direction.

  The plurality of electrode portions 14aa, 14ab, 14ac shown in FIG. 8 have different lengths in the Y direction, that is, lengths from one end E3 to the other ends E4a, E4b, E4c. With such a configuration, it is possible to increase the frequency band in which power generation is possible, and thus it is possible to generate power according to external vibrations of various frequencies.

  In addition, although several electrode part 14aa, 14ab, 14ac demonstrated the example from which the length of a Y direction differs, respectively, it is not limited to this. For example, the plurality of electrode portions 14aa, 14ab, and 14ac may have different lengths in the X direction. Further, the number of electrode portions is not limited to three, and may be two or four or more.

  Examples will be described below.

(Example 1)
In Example 1, the output voltage and the instantaneous output power were measured using the vibration power generation element 10 of the embodiment. As Comparative Example 1, the output voltage and the instantaneous output power were measured using the vibration power generation element of the reference example.

  In the vibration power generation element 10 of Example 1, the first electrode 11 and the second electrode 14 are formed of a flat copper plate having a thickness of 40 μm. Further, as the electret 12, Teflon (registered trademark) CYTOP (Asahi Glass Co., Ltd.) was used. The insulating layer 13 is made of an epoxy resin having a thickness of 50 μm.

  In Comparative Example 1, the plate-like upper electrode and the lower electrode arranged opposite to each other vibrate in the vertical direction (thickness direction), and power generation is performed by repeating surface contact and peeling via a dielectric and an electret. The vibration power generation element to be used was used. In Comparative Example 1, a spacer is disposed between the dielectric and the electret in order to assist the separation between the upper electrode and the lower electrode.

  FIG. 9 shows a comparison result of output voltage and instantaneous power between Example 1 and Comparative Example 1. As shown in FIG. 9, one period of the example is 71 ms and one period of the comparative example 1 is 57 ms. Here, “one period” means a movement until two electrodes come into contact with each other, peel off, and come into contact again.

  Focusing on the waveform of the output voltage, Example 1 can extract the voltage for a longer time than Comparative Example 1. Focusing on the instantaneous power, the output time of Example 1 is 50 ms, while the output time of Comparative Example 1 is 26 ms. Further, the peak value of the instantaneous power in Example 1 is 600 μw, whereas the peak value of the instantaneous power in Comparative Example 1 is 350 μW.

  Thus, in Example 1, since the voltage can be taken out for a longer time than in Comparative Example 1, the output time can be extended. In Example 1, the instantaneous power can be made larger than that in Comparative Example 1.

(Example 2)
In Example 2, the power generation amount was measured using the vibration power generation element 10 of the embodiment. Further, as Comparative Examples 2 to 5, the power generation amount was measured using the vibration power generation element of the reference example. In Example 2 and Comparative Examples 2 to 5, the vibration condition was 1.96 m / s ² .

  In Example 2, the same vibration power generation element 10 as in Example 1 was used.

  In Comparative Examples 2 to 5, a vibration power generation element having a configuration equivalent to that of Comparative Example 1 was used. In Comparative Example 2, the vibration power generation element of the reference example having no spacer was used. In Comparative Examples 3 to 5, spacers having spacer heights of 24 μm, 36 μm, and 48 μm were used, respectively.

  FIG. 10 shows a comparison result of the power generation amount between Example 2 and Comparative Examples 2 to 5. As shown in FIG. 10, the second child example 2 was able to obtain a higher power generation amount than the comparative examples 2 to 5.

  Although the present invention has been fully described in connection with preferred embodiments with reference to the accompanying drawings, various variations and modifications will be apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as long as they do not depart from the scope of the present invention.

  The vibration power generation element of the present invention is useful for a self-supporting wireless sensor for monitoring social / traffic infrastructure, a self-supporting power source of a wearable terminal / healthcare terminal, and the like.

DESCRIPTION OF SYMBOLS 10 Vibration power generation element 11 1st electrode 12 Electret 13 Insulating layer 14, 14a 2nd electrode 14aa, 14ab, 14ac Electrode part 15 Weight 16 Stopper 17 Fixed part 18 Load 21, 22 Current flow direction

Claims (10)

A first electrode supported by a cantilever structure in which one end is fixed to a fixed portion and the other end is a free end;
A second electrode supported by a cantilever structure facing the first electrode, having one end fixed to the fixing portion and the other end being a free end;
An electret disposed between the first electrode and the second electrode;
An insulating layer disposed between the first electrode and the second electrode;
The second electrode that is in contact with the first electrode via the electret and the insulating layer is peeled off from the first electrode by restricting the movement of the first electrode toward the second electrode. A stopper to
A vibration power generation device comprising:   2. The vibration power generation element according to claim 1, wherein the stopper peels the second electrode from the first electrode with the other end of the second electrode as a starting point.   3. The vibration power generation element according to claim 1, wherein the electret is in contact with one of the first electrode and the second electrode.   The vibration according to any one of claims 1 to 3, wherein the stopper is disposed inside a movable range of the other end of the second electrode in a direction in which the first electrode and the second electrode face each other. Power generation element.   The area of the surface of the second electrode on the side facing the first electrode is smaller than the area of the surface of the first electrode on the side facing the second electrode. The vibration power generation element according to 1.   6. The vibration power generation according to claim 5, wherein the stopper is disposed at a position that overlaps the first electrode but not the second electrode when viewed from a direction in which the first electrode and the second electrode face each other. element.   The vibration power generation element according to claim 1, wherein the stopper is disposed along a direction extending from one end of the first electrode toward the other end. Furthermore,
The vibration power generation device according to any one of claims 1 to 7, further comprising a weight provided on the second electrode.   The vibration power generating element according to claim 8, wherein the weight is provided at the other end of the second electrode.   10. The vibration power generation element according to claim 1, wherein the second electrode includes a plurality of electrode portions that are connected at one end and supported by a cantilever structure having the other end as a free end. .

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