JP2013123337A - Power generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power generator capable of extracting huge electric power even when a small external force is applied to the generator.SOLUTION: In a power generator 1, a fixed base 3 provided with a fixed electrode 4 is opposed to a movable base 5 provided with an electret 7 having plural charging areas 11, and the movable base 5 is attached to a case material 2 by a support member 8. More specifically, the movable base 5 is attached to the case material 2 by the support member 8 such that, when an external force is applied to the movable base 5, the movable base 5 can swing in a plane orthogonal to a direction in which the movable base 5 is opposed to the fixed base 3 while the movable base 5 remains opposed to the fixed base 3, with a part between first and second end portions 8a and 8b of the support member 8 serving as a fulcrum.

Description

  The present invention relates to a power generation device using an electret, and more particularly to a movable substrate on which an electret having a plurality of charged regions is formed and a power generation device in which a fixed electrode is disposed so as to face the movable substrate.

  Conventionally, various electrostatic induction power generation devices have been proposed as power sources that do not require battery replacement. For example, Patent Literature 1 below discloses a power generation device 1001 shown in FIG.

  The power generation device 1001 has a case 1002. A fixed substrate 1003 is fixed in the case 1002. An electret 1004 is provided on the upper surface of the fixed substrate 1003 so as to cover one of the pair of comb-like electrodes. The electret 1004 has a plurality of strip-shaped portions. The strip-like part is charged positively or negatively.

  A movable substrate 1005 is disposed above the fixed substrate 1003. A counter electrode 1006 is formed on the lower surface of the movable substrate 1005. The counter electrode 1006 is composed of a pair of comb-like electrodes. The movable substrate 1005 is supported on the case 1002 by springs 1007 and 1008.

  When an external force such as acceleration is applied to the power generation apparatus 1001, the movable substrate 1005 vibrates in the direction indicated by the arrow, that is, in the horizontal direction. As a result, a state in which the counter electrode 1006 is opposed to the electret 1004 and a state in which the counter electrode 1006 is not opposed are developed. By repeating this, electric power can be taken out in the power generation apparatus 1001.

  Patent Document 2 below discloses a power generation device in which a fixed substrate having a counter electrode is opposed to a movable substrate provided with an electret. In Patent Document 2, spring members are respectively arranged between a pair of side surfaces facing each other and a case inner wall of the movable substrate. This spring member is composed of first and second plate spring members. The first and second plate spring members are fixed to each other at both ends, and are separated by a central portion. The central part of the spring member is in contact with the side surface of the movable substrate. That is, a pressing force is applied between the side surface of the movable substrate and the inner wall of the case at the center of the spring member. When an external force such as acceleration is applied, the spring members are alternately compressed, and the movable substrate can vibrate in the horizontal direction.

JP 2010-136598 A JP 2008-161036 A

  In the electrostatic induction power generation device described in Patent Document 1 or Patent Document 2, the movable substrate vibrates so as to reciprocate in the surface direction of the fixed substrate in a state where the movable substrate faces the fixed substrate. In order to enable such vibration, springs 1007 and 1008 and the spring member described in Patent Document 2 are used. However, in such a structure, it was necessary to apply a large acceleration of about 100 mG to vibrate the movable substrate.

  On the other hand, the acceleration of vibrations generated by human movements and devices used in daily life is about several mG. Therefore, in the conventional power generator, the movable substrate cannot be vibrated with such a small acceleration.

  An object of the present invention is to provide a power generation device that can extract a large amount of electric power by electrostatic induction even when a small external force generated by a human action or the like, for example, a small acceleration is applied.

  The power generation device according to the present invention includes a movable substrate, a fixed substrate, a fixed electrode, a support member, and a case material. The movable substrate has an electret, and has a plurality of charged regions in which the electret is arranged in parallel in the surface direction. The fixed substrate is provided to face the movable substrate. The fixed electrode is provided on the fixed substrate so as to face the plurality of charged regions. The fixed electrode has a plurality of electrode portions arranged in parallel in the surface direction. The support member has a first end and a second end, and the first end is fixed to the movable substrate. The second end portion of the support member is fixed to the case material. In the power generation device according to the present invention, the portion between the first and second ends of the support member in a plane orthogonal to the facing direction while maintaining the state where the movable substrate faces the fixed substrate when an external force is applied. The movable substrate is connected to the case material by a support member so that the movable substrate swings about the fulcrum.

  On the specific situation with the electric power generating apparatus which concerns on this invention, a supporting member consists of a leaf | plate spring whose direction which connects a 1st edge part and a 2nd edge part is a length direction. In this case, by using the leaf spring, the movable substrate can be reliably swung with a small external force with the portion between the first and second ends of the support member as a fulcrum.

  In another specific aspect of the power generation device according to the present invention, the movable substrate includes a support substrate and an electret laminated on the support substrate, and the support substrate and the support member are made of different members, and the support substrate The first end of the support member is fixed to the frame. In this case, since the electret is supported by the support substrate, the movable substrate is difficult to bend.

  In another specific aspect of the power generation device according to the present invention, the power generation device further includes a stopper provided to regulate a swing range when the movable substrate swings with an external force while maintaining a state of facing the fixed substrate. It has been. In this case, since the swing range of the movable substrate is restricted, the movable substrate is hardly damaged.

  In still another specific aspect of the power generation device according to the present invention, the plurality of charging regions include a first end located on the support member side, and a second end opposite to the first end. And having a shape that increases in width as it goes from the first end to the second end, and a plurality of charged regions are radial as they go from the first end to the second end The plurality of electrode portions of the fixed electrode have the same shape as the plurality of charged regions. In this case, even greater power can be extracted when the movable substrate swings. Preferably, each charging region and each electrode portion has a substantially triangular shape. In this case, since each electrode portion has a simple shape in each charging region, these can be easily formed.

  In still another specific aspect of the power generator according to the present invention, adjacent side edges are parallel to each other between adjacent charging regions. In this case, even greater power can be generated.

  In still another specific aspect of the power generator according to the present invention, the length connecting the first and second ends of the support member is a, the centers of the plurality of charged regions arranged radially, and the support of the movable substrate When the distance between the end faces to which the members are joined is b, b / a is in the range of 0.27 to 0.55. In this case, much larger electric power can be taken out.

  In the power generation device according to the present invention, since the movable substrate is connected to the case material by the support member as described above, when the external force is applied, the movable substrate is maintained while facing the fixed substrate. It swings with the portion between the first and second ends as a fulcrum. Therefore, even when a small external force is applied, the movable substrate is reliably swung. Therefore, electric power can be taken out by a small external force generated by a human action or the like.

(A) And (b) is a typical side sectional view and a typical front sectional view of a power generator concerning a 1st embodiment of the present invention. (A) is a typical front view which shows the movable substrate and support member which are used with the electric power generating apparatus which concerns on the 1st Embodiment of this invention, (b) is the typical top view. It is typical sectional drawing for demonstrating the electret charging method used for the electric power generating apparatus which concerns on the 1st Embodiment of this invention. It is a typical see-through | perspective top view of the fixed board | substrate 3 used with the electric power generating apparatus which concerns on the 1st Embodiment of this invention. It is a schematic plan view which shows the positional relationship of the some charging area in the electric power generating apparatus which concerns on the 1st Embodiment of this invention. FIG. 6 is a schematic plan view showing a positional relationship between a plurality of charged regions in a preferred modification of the power generator according to the first embodiment of the present invention. (A) And (b) is each typical top view for demonstrating the state to which a movable board | substrate rock | fluctuates in the electric power generating apparatus which concerns on the 1st Embodiment of this invention. (A)-(c) is each typical sectional drawing for demonstrating operation | movement of the electric power generating apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows the relationship between ratio b / a in the electric power generating apparatus which concerns on the 1st Embodiment of this invention, and the resonant frequency of the vibration of a movable substrate. It is a schematic plan view for demonstrating the other modification of the electric power generating apparatus which concerns on the 1st Embodiment of this invention. (A) And (b) is a typical side view for demonstrating the further another modification of the electric power generating apparatus which concerns on the 1st Embodiment of this invention. It is typical sectional drawing which shows an example of the conventional electric power generating apparatus.

  Hereinafter, the present invention will be clarified by describing specific embodiments of the present invention with reference to the drawings.

  1A and 1B are a schematic side cross-sectional view and a schematic front cross-sectional view of the power generation apparatus 1 according to the first embodiment of the present invention. The power generation device 1 has a case material 2. The case material 2 has an opening 2a opened upward. The shape of the case material 2 is not particularly limited, but in the present embodiment, the planar shape of the case material 2 is a rectangle. The case material 2 can be formed of an appropriate rigid material such as an insulating ceramic such as alumina, a synthetic resin, or a metal. In addition, when the case material 2 consists of metals, it is desirable to electrically insulate from the conductive member for taking out electric power suitably.

  The fixed substrate 3 is joined to the case material 2 so as to seal the opening 2 a of the case material 2. The fixed substrate 3 is made of an appropriate insulating material such as insulating ceramics such as alumina or synthetic resin. A fixed electrode 4 is formed on the surface (lower surface) of the fixed substrate 3 that is joined to the case material 2. The fixed electrode 4 is made of an appropriate metal such as Ag, Al, Cu, Au, or an alloy thereof, or an alloy mainly composed of these metals. The shape of the fixed electrode 4 will be described later.

  A movable substrate 5 is disposed in a space sealed by the case material 2 and the fixed substrate 3. In the present embodiment, the movable substrate 5 includes a support substrate 6 and an electret 7 provided on the support substrate 6. The support substrate 6 is made of metal in the present embodiment, but may be formed of ceramics, synthetic resin, or the like.

  The movable substrate 5 is supported on the case material 2 by a support member 8 made of a leaf spring. Fig.2 (a) is a typical front view which shows the movable substrate 5 and the supporting member 8 which are used with the electric power generating apparatus 1 which concerns on the 1st Embodiment of this invention, FIG.2 (b) is the model. FIG.

  As shown in FIGS. 2A and 2B, the support substrate 6 has a rectangular plate shape. The support substrate 6 has first and second side surfaces 6a and 6b facing each other. The first end portion 8a of the support member 8 is fixed to the second side surface 6b. Further, the second end portion 8 b of the support member 8 is fixed to the inner wall of the case material 2. The leaf spring constituting the support member 8 is made of an appropriate metal such as stainless steel. The first end 8a of the support member 8 is fixed to the center in the length direction of the second side surface 6b. Therefore, the movable substrate 5 is supported by the support member 8 so that the support member 8 can swing around the portion between the first end portion 8a and the second end portion 8b.

  On the other hand, a plurality of recesses 6 c are formed on the upper surface of the support substrate 6. A plurality of recesses 6 d are also formed on the lower surface of the support substrate 6. The recesses 6c and 6d have a square planar shape as shown in FIG. As shown in FIGS. 1A and 1B, a rotating body 9 is disposed in the recesses 6c and 6d. The diameter of the rotating body 9 is substantially equal to the distance between the bottom of the recess 6 c and the lower surface of the fixed substrate 3 and the distance between the bottom of the recess 6 d and the inner bottom surface of the case member 2. The rotating body 9 is housed so as to be rotatable in the recesses 6c and 6d.

  Therefore, the distance between the upper surface of the movable substrate 5 and the lower surface of the fixed substrate 3 and the distance between the lower surface of the movable substrate 5 and the inner bottom surface of the case material 2 can be made constant by the rotating body 9. ing. Since the distance between the upper surface of the movable substrate 5 and the lower surface of the fixed substrate 3 is constant, the distance between the electret 7 and the fixed electrode 4 is constant. That is, while maintaining the state where the electret 7 is opposed to the fixed electrode 4, the movable substrate 5 is located between the first and second end portions 8 a and 8 b of the support member 8 in a plane orthogonal to the facing direction. It can swing as a fulcrum.

  In this embodiment, the rotator 9 is constituted by a sphere made of metal. However, the rotating body 9 may be formed of ceramics, synthetic resin, or the like.

  Further, the arrangement of the rotating bodies 9 is not particularly limited, and it is desirable that a plurality of rotating bodies 9, preferably three or more rotating bodies 9 are uniformly arranged in a portion surrounding the fixed electrode 4. Thereby, the interval can be kept constant.

  In the power generation device 1 of the present embodiment, the movable substrate 5 swings as described above when an external force such as acceleration is applied. In the conventional power generation devices described in Patent Literature 1 and Patent Literature 2, the movable substrate vibrates so as to reciprocate in the surface direction of the fixed substrate in a state where the movable substrate faces the fixed substrate. For this reason, a pair of spring members must be disposed on both sides of the movable substrate. For this reason, the movable substrate does not vibrate sufficiently with a small external force, and power cannot be extracted. On the other hand, in the power generation device 1 of the present embodiment, the movable substrate 5 swings as described above, so that electric power can be extracted with a slight external force. Therefore, electric power can be generated even when a small acceleration generated by a human motion or the like is applied. This will be clarified by describing the electret 7 and the fixed electrode 4 in more detail.

As shown in FIG. 2B, an electret 7 is provided on a support substrate 6 made of metal. That is, the electret 7 is disposed in a region facing the region where the fixed electrode 4 is formed. The electret 7 is made of a synthetic resin or an inorganic material. Examples of the synthetic resin include a fluororesin such as polytetrafluoroethylene. Examples of the inorganic material include SiO ₂ . The electret 7 can be formed of an appropriate material that can be positively or negatively charged. In the present embodiment, the electret 7 is made of polytetrafluoroethylene. Although not particularly shown, a protective layer may be formed so as to cover the electret 7. As such a protective layer, an appropriate inorganic material such as SiN, AlN, Al ₂ O ₃ or an appropriate organic material can be used.

  In the present embodiment, the electret 7 has a plurality of charged regions 11. Each charging region 11 has a first end portion 11a located on the support member 8 side and a second end portion 11b on the opposite side. The plurality of charged regions 11 have a shape that increases in width from the first end portion 11a to the second end portion 11b. More specifically, in the present embodiment, each charging region 11 has a substantially triangular planar shape. That is, each charging region 11 has a substantially triangular planar shape with the first end portion 11a side as a vertex.

  However, in this embodiment, each charging region 11 has a substantially isosceles triangle shape in which the apex on the first end portion 11a side of the isosceles triangle is cut off, but is in the shape of an isosceles triangle. Also good. Further, the second end portion 11b side of the plurality of charging regions 11 may be a circular arc-shaped portion centering on a swing center described later. That is, the charging region 11 may have a fan shape.

  The plurality of charged regions 11 are positively or negatively charged. A method of charging the electret 7 will be described with reference to FIG. FIG. 3 is a schematic cross-sectional view for explaining a charging method of the electret 7 used in the power generation device 1 according to the first embodiment of the present invention.

  As shown in FIG. 3, a metal mask 12 is disposed on the upper surface of the electret 7 provided on the support substrate 6. The metal mask 12 has an opening 12a. The opening 12 a is provided at a position corresponding to the charging area 11 of the electret 7.

  As shown in FIG. 3, corona discharge is performed from above with the metal mask 12 placed on the electret 7. As a result, a negative charge is charged in the portion exposed by the opening 12a of the electret 7 as illustrated. Thereby, the part exposed by the opening part 12a of the electret 7 can be used as the charging area 11 which is a negative charging area. Note that a positive charge may be charged. In that case, the charging region 11 can be a positive charging region.

  As described above, the plurality of charged regions 11 having the shape shown in FIG. 2B can be easily formed.

  In the present embodiment, in the plurality of charging regions 11, the plurality of charging regions 11 are extended radially from the first end portion 11 a toward the second end portion 11 b side. The radial center preferably coincides with the swing center O when the movable substrate 5 swings. Thereby, large electric power can be taken out. However, the radial center and the swing center O do not necessarily coincide with each other.

  FIG. 4 is a schematic perspective plan view of the fixed substrate 3 used in the power generator 1 according to the first embodiment of the present invention. Specifically, FIG. 4 is a schematic plan view showing the fixed electrode 4 through the fixed substrate 3. The fixed electrode 4 includes a first electrode 4A and a second electrode 4B. The first electrode 4 </ b> A has a plurality of electrode portions 13. The second electrode 4B has a plurality of electrode portions 14. Each of the electrode portions 13 and 14 has a substantially triangular planar shape, similar to the charging region 11 of the electret 7 described above. One end of each of the plurality of electrode portions 13 is commonly connected by a bus bar 15. A bus bar 15 is connected to the first extraction electrode 16. One ends of the plurality of electrode portions 14 are commonly connected by a bus bar 17. A bus bar 17 is connected to the second extraction electrode 18.

  The plurality of electrode portions 13 and the plurality of electrode portions 14 are interleaved with each other like electrode fingers of known comb electrodes. But as shown in FIG. 4, the some electrode part 13 and the some electrode part 14 are extended radially. That is, the plurality of electrode portions 13 and 14 are formed so as to be radial around the virtual radiation center X.

  The plurality of electrode portions 13 and 14 have the same shape as the charging region 11 of the electret 7 as described above. In this case, the plurality of electrode portions 13 are formed such that the end portion on the radiation center X side is narrow and the width becomes wider toward the opposite end portion. Similarly, the plurality of electrode portions 14 are also formed so that the end on the radiation center X side is narrow and the width becomes wider toward the opposite end. However, the plurality of electrode portions 13 are commonly connected by the bus bar 15 on the side close to the radiation center X. On the other hand, the plurality of electrode portions 14 are commonly connected by a bus bar 17 at the end opposite to the radiation center X.

  The electrode portions 13 and 14 also have a substantially isosceles triangular shape, similar to the electrified region 11 of the electret 7, but may have an isosceles triangular shape or a sector shape. It may be.

  FIG. 5 is a schematic plan view showing the positional relationship between the plurality of charged regions 11 in the power generation device 1 according to the first embodiment of the present invention. FIG. 6 is a schematic plan view showing the positional relationship between the plurality of charged regions 11 in a preferred modification of the power generator 1 according to the first embodiment of the present invention. In FIG. 5, for ease of explanation, the width of each charging region 11 is shown slightly smaller. The charging region 11 has a pair of sides 11c and 11d, and the pair of sides 11c and 11d extends in a radial direction centered on the radiation center Y, that is, in a radial direction of a circle centered on the radiation center Y. In this case, the space between the adjacent charging regions 11 is increased.

  On the other hand, in the modification shown in FIG. 6, in the adjacent charging regions 11, 11, the side 11 c of one adjacent charging region 11 and the side 11 d of the other adjacent charging region 11 are adjacent to each other. It is parallel to the radial direction R passing through the center between the matching sides 11c and 11d. In other words, the side edges 11c and 11d adjacent to each other are not parallel to the radial direction of the circle centered on the radiation center Y. In this way, it is desirable that the adjacent sides 11c and 11d of the adjacent charging regions 11 and 11 are parallel to each other, particularly parallel to the radiation direction R indicated by the one-dot chain line in FIG. By making the side 11c of one adjacent charging region 11 and the side 11d of the other adjacent charging region 11 parallel to a radial direction R passing through the center between the adjacent sides 11c, 11d, The space between the charged regions 11 and 11 can be reduced. Thereby, the amount of power generation can be increased. In this case, it is desirable that the fixed electrode 4 has a similar shape. Thereby, the facing area between the charging region 11 of the electret 7 and the fixed electrode 4 can be further increased. Therefore, the power generation amount can be further increased.

  Next, with reference to FIG.7 and FIG.8, operation | movement of the electric power generating apparatus 1 is demonstrated. FIGS. 7A and 7B are schematic plan views for explaining a state in which the movable substrate 5 swings in the power generation apparatus 1 according to the first embodiment of the present invention. Specifically, FIGS. 7A and 7B are schematic plan views showing a state in which the fixed substrate 3 is watermarked. FIGS. 8A to 8C are schematic cross-sectional views for explaining the operation of the power generation apparatus 1 according to the first embodiment of the present invention. As shown in FIGS. 8A to 8C, a load 19 is connected to the fixed electrode 4 having the electrode portions 13 and 14.

  FIG. 7A shows a state of the movable substrate 5 before an external force is applied to the power generation apparatus 1. From this state, when an external force such as an acceleration generated by a human action or the like is applied, the movable substrate 5 swings as indicated by an arrow in the figure. That is, as shown in FIG. 7B, the movable substrate 5 is displaced around the fulcrum 8 c of the support member 8. The fulcrum 8C is the swing center O. Since the supporting member 8 is made of a leaf spring, the movable substrate 5 is moved from the state shown in FIG. 7 (b) to the state shown in FIG. It will move toward the opposite side. That is, the movable substrate 5 swings as indicated by an arrow in FIG.

  FIG. 8A shows a state before an external force is applied to the power generation apparatus 1 as in FIG. Of the electrode portions 13 and 14 of the fixed electrode 4 of the fixed substrate 3, it is assumed that the electrode portion 13 faces the charging region 11. In this case, a positive charge is induced in the electrode portion 13 by electrostatic induction.

  Thereafter, when an external force is applied to the power generation device 1, the movable substrate 5 moves to the right in the drawing with respect to the fixed substrate 3 as shown in FIG. 8B, and the electrode portion 14 faces the charging region 11. To do. In this state, a positive charge is induced in the electrode portion 14 by electrostatic induction. Further, as shown in FIG. 8C, the movable substrate 5 moves to the right side of the drawing with respect to the fixed substrate 3, and the electrode portion 13 again faces the charging region 11. In this case, a positive charge is induced again in the electrode portion 13.

  Therefore, when the movable substrate 5 swings as described above, AC power can be taken out between the first electrode 4A having the electrode portion 13 and the second electrode 4B having the electrode portion 14. That is, AC power can be applied to the load 19 shown in FIGS.

  As described above, in the power generation device 1 according to the present embodiment, the movable substrate 5 is arranged in the case material 2 so as to swing with a part of the support member 8 as a fulcrum. Can reliably generate power even when a small acceleration is applied.

  In order to extract a large amount of power with a small external force, it is more desirable that the center position of the radial charging region 11 has a ratio b / a described below in a range of 0.27 to 0.55. This will be described with reference to FIGS.

  The length a in FIG. 2B, that is, the length of the support member 8 is a. Here, the length of the support member 8 refers to the length from the portion of the support member 8 joined to the movable substrate 5 to the portion of the support member 8 joined to the case material 2. Further, the length from the fulcrum 8c, which is the swing center O shown in FIG. 2B, to the portion of the support member 8 that is joined to the movable substrate 5 is b. In other words, the length from the radial center of the plurality of charged regions 11 to the portion of the support member 8 joined to the movable substrate 5 is b. The ratio b / a of the length b to the length a was variously changed, and the change in the resonance frequency due to the vibration of the movable substrate 5 was obtained. The results are shown in FIG. This resonance frequency is a resonance frequency of vibration caused by an external force applied to the power generation device 1.

  The frequency of vibration obtained by human movement, such as walking, is in the range of 1 Hz to 50 Hz. As is clear from FIG. 9, in order to vibrate in such a low frequency band, the ratio b / a may be set so that the resonance frequency is in the vicinity of 1 Hz to 50 Hz. Therefore, if the ratio b / a is in the range of 0.27 to 0.55, the resonance frequency can be set to 1 to 50 Hz. Therefore, in order to extract sufficient power with such low-frequency vibration, it is desirable that the ratio b / a be in the range of 0.27 to 0.55.

  In this embodiment, the resonance frequency when the movable substrate 5 vibrates can be easily adjusted by adjusting the thickness and width of the support member 8 made of the plate spring. Therefore, the power generation device 1 can be easily provided according to the use, that is, according to the frequency of vibration caused by the applied external force.

  FIG. 10 is a schematic plan view showing another modification of the power generation device 1 according to the first embodiment of the present invention. Specifically, FIG. 10 is a schematic plan view showing a state in which the fixed substrate 3 is seen through. In the power generation device 1, the movable substrate 5 swings with the intermediate position of the support member 8 as a fulcrum. If the swing range is too large, the movable substrate 5 may collide with the inner wall of the case material 2. When the movable substrate 5 collides with the inner wall of the case material 2, the movable substrate 5 may be damaged. Alternatively, the movable substrate 5 may be displaced beyond the allowable deformation range of the support member 8. That is, when the support member 8 is deformed beyond the elastic recovery range, the movable substrate 5 cannot be continuously swung with the middle of the support member 8 as a fulcrum.

  In the modification shown in FIG. 10, the stopper 21 is fixed to the inner wall of the case material 2 in order to regulate the swing range of the movable substrate 5. That is, the stopper 21 protrudes from the inner wall of the case material 2 toward the movable substrate 5 so that the swing range is restricted in the swing direction of the movable substrate 5. The swing range of the movable substrate 5 can be adjusted by this protrusion amount.

  By providing the stopper 21, it is possible to prevent the movable substrate 5 from colliding with the inner wall of the case material 2. Or the deformation | transformation beyond the tolerance | permissible_range of the support member 8 can be prevented.

  FIGS. 11A and 11B are schematic side views for explaining still another modification of the power generation device 1 according to the first embodiment of the present invention. In the above embodiment, the first end 8a of the support member 8 is fixed to the side surface of the support substrate 6 constituting the movable substrate 5, but as shown in FIGS. 11 (a) and 11 (b), The support member 8 may be connected to the support substrate 6 by providing the support substrate 6 with a recess 6e and fitting the support member 8 into the recess 6e from the first end.

DESCRIPTION OF SYMBOLS 1 ... Electric power generation apparatus 2 ... Case material 2a ... Opening 3 ... Fixed substrate 4 ... Fixed electrode 4A ... 1st electrode 4B ... 2nd electrode 5 ... Movable substrate 6 ... Support substrate 6a, 6b ... Side surface 6c, 6d, 6e ... Recess 7 ... electret 8 ... support member 8a ... first end 8b ... second end 8c ... fulcrum 9 ... rotating body 11 ... charging region 11a ... first end 11b ... second end 11c, 11d ... Side 12 ... Metal mask 12a ... Opening parts 13 and 14 ... Electrode part 15 ... Bus bar 16 ... First extraction electrode 17 ... Bus bar 18 ... Second extraction electrode 19 ... Load 21 ... Stopper

Claims (8)

A movable substrate having an electret and having a plurality of charged regions in which the electret is arranged in parallel in the surface direction;
A fixed substrate provided to face the movable substrate;
A fixed electrode provided on the fixed substrate so as to face the plurality of charging regions, and having a plurality of electrode portions arranged side by side in a plane direction;
A support member having a first end and a second end, the first end being fixed to the movable substrate;
A case material to which a second end of the support member is fixed,
While the movable substrate is kept facing the fixed substrate when an external force is applied, the portion between the first and second ends of the support member is used as a fulcrum in a plane orthogonal to the facing direction. The power generation device, wherein the movable substrate is connected to the case material by the support member so that the movable substrate swings.   The power generator according to claim 1, wherein the support member includes a leaf spring whose length direction is a direction in which the first end and the second end are connected.   The movable substrate includes a support substrate and an electret laminated on the support substrate, and the support substrate and the support member are separate members, and the support substrate has a first end portion of the support member. The power generator according to claim 1 or 2, which is fixed.   The stopper according to any one of claims 1 to 3, further comprising a stopper provided to regulate a swing range when the movable substrate swings with an external force while maintaining a state of facing the fixed substrate. The power generator described. The plurality of charging regions have a first end located on the support member side and a second end opposite to the first end, and the second end from the first end to the second end A shape having a width that widens toward the end, and a plurality of charged regions are radially extended from the first end to the second end,
The power generator according to any one of claims 1 to 4, wherein the plurality of electrode portions of the fixed electrode have the same shape as the plurality of charged regions.   The power generation device according to claim 5, wherein each charging region and each electrode portion has a substantially triangular shape.   The power generation device according to claim 5 or 6, wherein adjacent side edges are parallel to each other between the adjacent charging regions. The length connecting the first and second end portions of the support member is a, between the centers of the plurality of radially arranged charging regions and the end surface of the movable substrate to which the support member is joined. The power generator according to any one of claims 1 to 7, wherein b / a is in a range of 0.27 to 0.55, where b is a distance.

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