JP2018157663A - Electromechanical converter and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve output of an electromechanical converter equally to a case where a charging film consists of a positively charged material and a negatively charged material, while constituting the charging film from a material which is positively or negatively charged.SOLUTION: An electromechanical converter configured to perform conversion between electric power and a motive force by utilizing an electrostatic interaction between a charging part and an opposite electrode comprises: a stationary substrate; a movable member which is movable while keeping a fixed distance to the stationary substrate; multiple charging films which are formed on a first surface of the movable member facing the stationary substrate and a second surface at an opposite side of the opposing surface in a staggered manner in a movement direction of the movable member on the first surface and the second surface and charged with the mutually same polarity; and multiple opposite electrodes which are disposed on a surface of the stationary substrate facing the movable member in the movement direction. Electric charge of an opposite polarity to the multiple charging films is induced in a region between the charging films on the first and second surfaces of the movable member, such that regions charged with the mutually opposite polarities are disposed on the first and second surfaces alternately in the movement direction.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an electromechanical transducer and a method for manufacturing the same.

  2. Description of the Related Art An electromechanical converter that performs conversion between electric power and power by an electrostatic interaction generated by using an electret having a property of retaining a charge semipermanently is known. For example, Patent Document 1 includes a first electrode provided with an electret and a second electrode spaced apart from the electret, and one of the electret and the second electrode with respect to the other due to external vibration. An electrostatic induction power generating element that moves relatively is described. Further, Patent Document 2 includes a first substrate having a plurality of electret films and a second substrate having a plurality of electrodes, and the first substrate performs a lateral movement, whereby the electret There is described an electrostatic induction generator that generates electric power by taking out the change of electric charge as electric energy by increasing and decreasing the overlapping area of the membrane and the electrode, and taking out the change of electric charge as electric energy.

JP 2012-138514 A International Publication No. 2010/047076

  In general, the charging film (charging portion) of such an electromechanical converter is composed only of a material that is charged positively or negatively. For example, in the case where the electromechanical converter is a generator that converts power into electric power, the generated output becomes a magnitude corresponding to the potential difference between the potential of the charging unit and the ground potential, so the generated output is further improved. It is difficult to let This also applies to the case where the electromechanical converter is an electric motor that converts electric power into power.

  When two types of charged film are produced with a positively charged material and a negatively charged material, and the charging part is configured by arranging them alternately to form the charged film with a material that charges positively or negatively Rather, the output of the electromechanical converter is improved. However, in that case, it is necessary to produce both a positively charged film and a negatively charged film with two kinds of materials, and the charging process at the time of manufacturing the electromechanical converter becomes complicated.

  The present invention improves the output of an electromechanical converter equivalent to the case where the charging film is composed of a material that is positively charged and a material that is negatively charged while the charging film is composed of a material that is positively or negatively charged. For the purpose.

  An electromechanical converter that performs conversion between electric power and power using electrostatic interaction between a charging unit and a counter electrode, and a fixed distance between the fixed substrate and the fixed substrate. The first surface and the second surface are the first surface that is the movable member that can be maintained and the first surface that is the opposite surface of the movable member to the fixed substrate, and the second surface that is the opposite surface of the movable member. A plurality of charged films formed alternately in the moving direction of the movable member on the two surfaces and charged to the same polarity with each other, and a plurality of counter electrodes arranged in the moving direction on the surface facing the movable member of the fixed substrate, And a charge having a polarity opposite to that of the plurality of charged films is induced in a region between the charged films on the first surface and the second surface of the movable member, whereby the first surface and the second surface In this aspect, the regions charged in opposite polarities are alternately arranged in the moving direction. Electromechanical transducer is provided to.

  In the above electromechanical transducer, the movable member is preferably made of a dielectric.

  In the electromechanical converter, the plurality of charged films include a plurality of grooves formed alternately in the moving direction between the first surface and the second surface on the first surface and the second surface of the movable member. The first surface and the second surface of the movable member are preferably flat surfaces that are free of irregularities due to the plurality of charging films and the plurality of groove portions.

  The electromechanical converter further includes a second fixed substrate disposed on the opposite side of the fixed substrate across the movable member, and the plurality of counter electrodes are opposed to the movable member of the second fixed substrate. It is preferable to arrange in the movement direction also on the surface.

  In the above electromechanical transducer, the movable member is rotatable around a rotation axis passing through the center of the movable member, and the plurality of charged films and the plurality of counter electrodes are radially arranged around the rotation axis. Preferably it is.

  In the above electromechanical transducer, the movable member is a slide plate that can reciprocate in a direction parallel to the fixed substrate, and the plurality of charged films and the plurality of counter electrodes each have a strip shape extending perpendicularly to the moving direction. It is preferable to have.

  The electromechanical converter includes a drive unit that applies a voltage whose polarity is alternately switched to the plurality of counter electrodes and moves the movable member by electrostatic force generated between the plurality of charged films and the plurality of counter electrodes. Furthermore, it is preferable to have.

  The electromechanical converter preferably further includes a power storage unit that accumulates electric power generated by electrostatic induction between the plurality of charged films and the plurality of counter electrodes according to the movement of the movable member.

  An electromechanical transducer manufacturing method that performs conversion between electric power and power using an electrostatic interaction between a charging unit and a counter electrode, the first surface of the substrate and the first surface of the substrate. A plurality of thin film regions made of an insulator are formed on the second surface, which is the surface opposite to the first surface, spaced apart from each other so that the first surface and the second surface are staggered. The step of grounding the substrate and disposing the discharge electrode so as to face each of the plurality of thin film regions and discharging electrons from the discharge electrode toward the substrate by discharging, thereby forming the plurality of thin film regions And charging with a step of charging at the same time and a step of arranging the substrate so as to face the fixed substrate so as to be movable at a fixed distance from the fixed substrate on which a plurality of counter electrodes are arranged. By the process, the thin film regions on the first surface and the second surface of the substrate Manufacturing in which charges having opposite polarities to a plurality of thin film regions are induced in a region between them, and regions charged to opposite polarities are alternately formed on the first surface and the second surface A method is provided.

  According to the electromechanical converter described above, the electromechanical conversion is equivalent to the case where the charging film is made of a material that is positively charged and the material that is negatively charged while the charging film is made of a material that charges positively or negatively. The output of the vessel can be improved.

1 is a schematic configuration diagram of an electromechanical converter 1. FIG. 2 is a perspective view of a power generation unit 10. FIG. 2 is a partial cross-sectional view of the power generation unit 10 along a circumferential direction centering on a rotation shaft 11. FIG. FIG. 3 is a cross-sectional view of the electromechanical converter 1 showing an arrangement example of the rotary weight 18. FIG. 4 is a diagram for explaining a charging method of the charging film 14. It is a fragmentary sectional view of another rotating member 12 '. It is a fragmentary sectional view of another electric power generation part 10 '. It is a schematic block diagram of another electromechanical converter 1 '. 6 is a schematic configuration diagram of still another electromechanical converter 2. FIG. 3 is a schematic configuration diagram of still another electromechanical converter 3. FIG. It is a figure which shows the difference of the output waveform of the electric power generation part of a comparative example, and the electric power generation part.

  Hereinafter, an electromechanical transducer and a manufacturing method thereof will be described with reference to the drawings. However, it should be understood that the present invention is not limited to the drawings or the embodiments described below.

  FIG. 1 is a schematic configuration diagram of an electromechanical converter 1. The electromechanical converter 1 includes a power generation unit 10 and a power storage unit 20. The power generation unit 10 includes a rotating shaft 11, a rotating member 12, a fixed substrate 13, a charging film 14, and counter electrodes 15 and 16. In FIG. 1, as the power generation unit 10, the upper surface of the fixed substrate 13 and the lower surface of the rotating member 12 are shown side by side. The electromechanical converter 1 uses the kinetic energy of the external environment to rotate the rotating member 12 and generates static electricity by electrostatic induction between the rotating member 12 and the counter electrodes 15 and 16, thereby generating electric power from the power. This is a power generation device (electret power generator) to be taken out.

  FIG. 2 is a perspective view of the power generation unit 10. FIG. 3 is a partial cross-sectional view of the power generation unit 10 along the circumferential direction around the rotation shaft 11. As shown in FIGS. 2 and 3, the power generation unit 10 includes a rotating member 12 and a fixed substrate 13 that are arranged in parallel to each other. A fixed interval is provided between the rotating member 12 and the fixed substrate 13. In FIG. 3, for the sake of simplicity, the horizontal direction of the drawing is illustrated so as to correspond to the circumferential direction of the rotating member 12 and the fixed substrate 13 (the direction of arrow C in FIG. 2).

  The rotation shaft 11 is an axis that serves as the rotation center of the rotation member 12, and penetrates the center of the rotation member 12 as shown in FIG. 2. The upper and lower ends of the rotating shaft 11 are fixed to a housing of the electromechanical converter 1 (not shown) via bearings. In addition, illustration of the rotating shaft 11 is abbreviate | omitted in FIG.

  The rotating member 12 is an example of a movable member, and is made of a known substrate material such as a silicon substrate or a glass epoxy substrate. The material of the rotating member 12 is preferably a dielectric rather than a metal. As shown in FIG. 2, the rotating member 12 has a disk shape, for example, and is connected to the rotating shaft 11 at the center thereof. In the power generation unit 10, for example, a rotating member 12 or a rotating weight having a weight balance deviation is attached separately from the rotating member 12. The rotating member 12 is a circumferential direction around the rotating shaft 11 by using the motion of a human body carrying the electromechanical converter 1 or vibration of a machine or the like to which the electromechanical converter 1 is attached as a power source. It can rotate in the direction of arrow C (clockwise and counterclockwise). That is, the rotating member 12 can move with a fixed distance from the fixed substrate 13.

  FIG. 4 is a cross-sectional view of the electromechanical transducer 1 showing an arrangement example of the rotary weight 18. FIG. 4 shows an example in which a rotating weight 18 for rotating the rotating member 12 is arranged separately from the rotating member 12 in the housing of the electromechanical converter 1. In the illustrated example, the rotary weight 18 is attached to a rotary shaft 11 ′ different from the rotary shaft 11 provided in the housing of the electromechanical converter 1. In this case, a gear 19 is attached to the rotary shaft 11, and a gear (speed increasing gear train) 19 'is attached to the rotary shaft 11', and the gear 19 and the gear 19 'are connected. Thereby, the rotary motion of the rotary weight 18 is transmitted to the gear 19 via the gear 19 ', and the rotary member 12 can be rotated.

  The fixed substrate 13 is made of a known substrate material such as a glass epoxy substrate. As shown in FIG. 2, the fixed substrate 13 has a disk shape, for example, and is disposed below the rotating member 12 so as to face the lower surface of the rotating member 12. Unlike the rotating member 12, the fixed substrate 13 is fixed to a housing of the electromechanical converter 1 (not shown).

The charging film 14 is a thin film made of an electret material, and is formed radially on the upper and lower surfaces of the rotating member 12 around the rotating shaft 11 except for the central portion around the rotating shaft 11. The charging film 14 includes a plurality of rectangular or substantially trapezoidal partial regions formed at intervals in the circumferential direction, and all are charged to the same polarity. In the following description, it is assumed that the charging film 14 is negatively charged. Examples of the electret material for the charging film 14 include resin materials such as fluororesins represented by CYTOP (registered trademark), polypropylene (PP), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polystyrene (PS), poly Polymer materials such as tetrafluoroethylene (PTFE), polyvinyldendifluoride (PVDF) or polyvinylfluoride (PVF), or inorganic materials such as silicon oxide (SiO ₂ ) or silicon nitride (SiN) are used. .

  The charging film 14 includes a lower surface (first surface) of the rotating member 12 that is a surface facing the fixed substrate 13, and an upper surface (second surface) of the rotating member 12 that is a surface opposite to the facing surface. In FIG. 1, they are shifted from each other by one pitch. That is, the charging film 14 is not disposed on the upper surface of the rotating member 12 at the circumferential position where the charging film 14 is disposed on the lower surface of the rotating member 12. Similarly, the charging film is disposed on the upper surface of the rotating member 12. The charging film 14 is not disposed on the lower surface of the rotating member 12 at the circumferential position where the 14 is disposed. In other words, the charging film 14 is alternately formed in the rotation direction of the rotating member 12 between the lower surface and the upper surface of the rotating member 12.

  As shown in FIG. 3, negative charges are concentrated on the surface of the charging film 14, and positive charges are induced on the surface of the charging film 14 that is in contact with the rotating member 12. Thereby, also in the rotating member 12, negative charges are induced on the surface in contact with the charging film 14, and positive charges are induced on the surface opposite to the charging film 14. For this reason, when the negatively charged charging film 14 is disposed on one side of the rotating member 12, positive charges are induced on the back side of the substrate. By constituting the rotating member 12 with a dielectric, a charge having a polarity opposite to that of the charging film 14 is induced on the surface of the rotating member 12 opposite to the charging film 14, and the surface on the opposite side is charged on the charging film 14. It becomes the opposite potential. Therefore, the same state as that in which both a positively charged charging film and a negatively charged charging film are produced can be realized with only one kind of negatively charged material.

  As described above, in the rotating member 12, a positive charge that is opposite to the charging film 14 is induced in a rectangular or substantially trapezoidal region 121 between the charging films 14 on the upper and lower surfaces. In the rotating member 12, the negatively charged charging films 14 are alternately arranged in the circumferential direction on the upper surface and the lower surface, and regions 121 other than the charging film 14 in which positive charges are induced are also circumferential on the upper surface and the lower surface. Alternatingly arranged in the direction. For this reason, on the upper and lower surfaces of the rotating member 12, positive charging regions 121 and negative charging films 14 charged in opposite polarities are alternately arranged in the circumferential direction. Further, their arrangement is shifted by one pitch (one rectangular or substantially trapezoidal region) between the upper surface and the lower surface.

  The counter electrodes 15 and 16 are each composed of a plurality of rectangular or substantially trapezoidal electrodes, and alternately on the upper surface of the fixed substrate 13 (the surface facing the rotating member 12) in the circumferential direction and centering on the rotating shaft 11 It is formed radially. The counter electrodes 15 and the counter electrodes 16 are formed at intervals in the circumferential direction, and are arranged at equal intervals, like the charging film 14. On the same circumference around the rotation axis 11, the counter electrode 15 and the counter electrode 16 have the same width, and the size is preferably the same as or substantially the same as the width of the charging film 14. Further, it is preferable that the number of the charging films 14, the number of the counter electrodes 15, and the number of the counter electrodes 16 on one side of the rotating member 12 are the same.

  When the rotating member 12 rotates, the overlapping area between the positive charging region 121 and the negative charging film 14 on the lower surface of the rotating member 12 and the counter electrodes 15 and 16 increases or decreases accordingly. For this reason, the electric charge drawn to the counter electrodes 15 and 16 by the electric field created by the positive charging region 121 and the negative charging film 14 increases or decreases as the rotating member 12 rotates. In this way, the power generation unit 10 generates power using electrostatic induction by generating an alternating current between the counter electrode 15 and the counter electrode 16.

  The power storage unit 20 includes a rectifier circuit 21 and a secondary battery 22, and generates electric power generated by electrostatic induction between the charging region 121 and the charging film 14 and the counter electrodes 15 and 16 according to the rotation of the rotating member 12. accumulate. Outputs from the counter electrodes 15 and 16 are connected to a rectifier circuit 21, and the rectifier circuit 21 is connected to a secondary battery 22. The rectifier circuit 21 is a bridge-type circuit having four diodes, and rectifies a current generated between the counter electrode 15 and the counter electrode 16. The secondary battery 22 is a chargeable / dischargeable battery such as a lithium secondary battery, accumulates electric power generated by the power generation unit 10, and supplies the electric power to a circuit to be driven (not shown).

  FIG. 5 is a diagram for explaining a charging method of the charging film 14. At the time of manufacturing the power generation unit 10 (electromechanical converter 1), first, an insulating material is used with an interval between the upper and lower surfaces of the dielectric substrate that becomes the rotating member 12 so that the upper surface and the lower surface are staggered. A plurality of thin film regions 14 'are formed. At this time, charging electrodes may be formed on the upper and lower surfaces of the dielectric substrate, and a resin film, for example, may be formed thereon as the thin film region 14 ′ that becomes the charging film 14. Then, as shown in FIG. 5, the dielectric substrate (rotating member 12) is grounded, and discharge electrodes (needle electrodes) 91 are arranged so as to face the thin film regions 14 'on the upper and lower surfaces of the dielectric substrate. Is done. A high voltage of about several thousand volts is applied to each discharge electrode 91 by the high voltage power supply 90.

  Then, since electrons are emitted from the discharge electrode 91 toward the dielectric substrate by corona discharge, the thin film regions 14 ′ on the upper and lower surfaces of the dielectric substrate are simultaneously negatively charged by the electrons to become the charged film 14. . As the thin film region 14 ′ is charged, positive charges having a polarity opposite to that of the charged film 14 are induced in the region 121 between the thin film regions 14 ′ on the upper and lower surfaces of the dielectric substrate. For this reason, on the upper and lower surfaces of the dielectric substrate, regions (charged regions 121 and charged films 14) charged with opposite polarities are alternately formed. In addition, the dielectric substrate is fixed to the rotating shaft 11 so as to face the fixed substrate 13 so as to be rotatable with a fixed distance from the fixed substrate 13 on which the counter electrodes 15 and 16 are arranged. The Through the above steps, the power generation unit 10 shown in FIG. 1 is completed, and when the counter electrodes 15 and 16 are electrically connected to the power storage unit 20, the electromechanical converter 1 is completed.

  Note that the charging step shown in FIG. 5 may be performed on each side of the rotating member 12. However, if charging is performed one side at a time, a part of the charge of the charged film 14 on one surface that has been charged first may be lost due to the influence of the next charging process. For this reason, it is preferable to charge the charging films 14 on both surfaces of the rotating member 12 at the same time because the potential of the charging film 14 can be maintained higher.

  FIG. 11A and FIG. 11B are diagrams showing differences in output waveforms between the power generation unit and the power generation unit 10 of the comparative example, respectively. FIG. 11A shows an output waveform of the voltage V from the counter electrodes 15 and 16 of the power generation unit having the same configuration as the power generation unit 10 except that there is no charging unit 14 on the upper surface side of the rotating member 12. 11 (B) shows an output waveform of the voltage V from the counter electrodes 15 and 16 of the power generation unit 10.

  In the power generation unit of the comparative example, the charging film 14 is formed only on the lower surface of the rotating member 12 (the surface facing the fixed substrate 13), and there is nothing corresponding to the positive charging region 121 described above. Electrostatic induction occurs in the negative potential region. For this reason, the waveform of the output voltage from the power generation unit of the comparative example is as shown in FIG. In this case, the power generation output from the power generation unit has a magnitude corresponding to the potential difference between the negative potential of the charging film 14 and the ground potential (the potential of the region between the charging films 14).

  On the other hand, in the power generation unit 10, the region 121 between the charged films 14, which was the ground potential in the above comparative example, becomes a positive potential, and electrostatic induction occurs in the region of the positive potential and the negative potential. For this reason, the waveform of the output voltage from the power generation unit 10 is as shown in FIG. The power generation output of the power generation unit 10 has a magnitude corresponding to the potential difference between the negative potential of the charging film 14 and the positive potential of the region 121, and the width A2 of the output waveform from the power generation unit 10 is from the power generation unit of the comparative example. It is larger than the width A1 of the output waveform. Therefore, in the electromechanical converter 1 having the power generation unit 10, the potential difference of electrostatic induction is larger than that of the electromechanical converter having the power generation unit of the comparative example, and the power generation output is improved.

  Further, in the electromechanical converter 1, since the positively charged region 121 can be formed only with a negatively charged material, the charged material only needs to be charged to one of the polarities. The forming process is simplified. In order to increase the amount of positive charges induced in the region 121 and increase the potential, it is preferable that the thickness of the dielectric substrate serving as the rotating member 12 is as thin as possible within a range in which necessary strength is ensured. .

  FIG. 6 is a partial cross-sectional view of another rotating member 12 '. The rotating member 12 ′ has a disk shape like the rotating member 12 of FIG. 2, and in FIG. 6, as in FIG. 3, the horizontal direction of the drawing is the circumferential direction of the rotating member 12 ′ (FIG. 2). The figure is modified so as to correspond to the direction of arrow C).

  On the upper and lower surfaces of the rotating member 12 ′, similarly to the rotating member 12, positive charging regions 121 and negative charging films 14 charged in opposite polarities are alternately arranged in the circumferential direction, respectively. Their arrangement is shifted by one pitch between the upper surface and the lower surface. However, the rotating member 12 is a flat substrate, and the charging film 14 protrudes from the upper and lower surfaces of the rotating member 12 by the thickness of the charging film 14, whereas the rotating member 12 ′ has the upper and lower surfaces for the charging film 14. A plurality of grooves are formed, and the surface of the rotating member 12 other than the grooves and the exposed surface of the charging film 14 are in the same plane. More specifically, a plurality of grooves are alternately formed in the circumferential direction on the upper and lower surfaces of the rotating member 12 ′, and the charging film 14 of the rotating member 12 ′ includes the grooves. It is formed to satisfy. For this reason, the upper and lower surfaces of the rotating member 12 ′ are flat surfaces free from unevenness due to the charging film 14 and the groove portions thereof.

  As described above, the charging film 14 may be embedded in the rotating member, and the upper and lower surfaces of the rotating member 12 ′ may be flat. In that case, the depth of each groove may be the same on the upper and lower surfaces of the rotating member 12 ′. For example, the depth of each groove is set to about ½ of the thickness of the rotating member 12 ′, You may align a bottom face at substantially the same height. Alternatively, in order to increase the positive charge induced in the region 121 on the lower surface side of the rotating member 12 ′, which is the surface facing the fixed substrate 13, on the side opposite to the fixed substrate 13 from the lower surface side of the rotating member 12 ′. The bottom surface of the charging film 14 on the upper surface side may be brought closer to the fixed substrate 13 by deepening a groove on the upper surface side.

  If the thickness of the rotating member is the same, the rotating member 12 'is closer to the surface of the rotating member on the opposite side of the charging film 14 than the rotating member 12 by the amount of the groove portion. The amount of positive charges induced in the region 121 increases. Therefore, when the rotating member 12 ′ is used, the potential difference between the negative potential of the charging film 14 and the positive potential of the charging region 121 becomes larger than when the rotating member 12 is used, and the power generation output is further improved. In addition, since the flatness of the surface of the rotating member increases when the charging film 14 is embedded in the rotating member rather than protruding from the surface of the rotating member, the rotating member 12 ′ is more stable with the fixed substrate 13. The distance between can be reduced. Since the voltage generated between the rotating member and the fixed substrate 13 is higher, the rotating member 12 'is preferable also in this respect. Further, since the rotating member 12 ′ has no surface irregularity due to the charging film 14, there is an advantage that the air resistance is low even when rotating at a high speed.

  FIG. 7 is a partial cross-sectional view of another power generation unit 10 ′. The power generation unit 10 ′ includes a fixed substrate in addition to the same rotating shaft 11 (not shown in FIG. 7), the rotation member 12, the fixed substrate 13, the charging film 14, and the counter electrodes 15 and 16 as those of the power generation unit 10 described above. 17. 7 is modified so that the horizontal direction of the drawing corresponds to the circumferential direction of the rotating member 12 and the fixed substrates 13 and 17 (in the direction of arrow C in FIG. 2), as in FIG.

  The fixed substrate 17 is the same as the fixed substrate 13 and is disposed on the upper side of the rotating member 12 so as to be vertically symmetrical with the fixed substrate 13 with the rotating member 12 interposed therebetween. Similarly to the fixed substrate 13, the counter electrodes 15 and 16 are alternately formed on the fixed substrate 17 in the circumferential direction. Like the power generation unit 10 ′, the fixed substrate 17, which is the second fixed substrate, so that the counter electrodes 15 and 16 face not only one surface (lower surface) but also the other surface (upper surface) of the rotating member 12. May be arranged. Thereby, compared with the electric power generation part 10, electric power generation amount can be increased easily.

  In the power generation unit 10 of the electromechanical converter 1 shown in FIG. 1, the generated current is taken out from the two sets of counter electrodes 15 and 16 formed on the fixed substrate 13. The form of the electromechanical transducer 1 is convenient because it is only necessary to take out current from only the electrodes on the stationary substrate 13 that is stationary, and electrical connection with the rotating member 12 that rotates is unnecessary. However, the present invention is not limited to this configuration, and both the rotating member 12 and the fixed substrate 13 may be electrically connected to the power storage unit 20 to extract the generated current. An example in this case will be described next.

  FIG. 8 is a schematic configuration diagram of another electromechanical transducer 1 ′. The power generation unit 10 ″ of the electromechanical converter 1 ′ has the same configuration as that of the power generation unit 10 of FIG. 1 except that the rotating member 12 is electrically connected to the power storage unit 20 and on the fixed substrate 13. Is different from the power generation unit 10 in that only one set of counter electrodes 15 is formed. In the power generation unit 10 ″, the rotating shaft 11 is made of a conductive member, and each rectangular or substantially trapezoidal partial region that forms the charging film 14 is connected to the rotating shaft 11 via an electrical contact. In the electromechanical converter 1 ′, the power storage unit 20 is electrically connected to the rotating shaft 11 and the counter electrode 15, and the generated current is taken out through them. Instead of connecting each partial region of the charging film 14 to the rotating shaft 11 one by one, the connecting wires may be connected to the rotating shaft 11 after connecting the partial regions to each other.

  FIG. 9 is a schematic configuration diagram of still another electromechanical transducer 2. The electromechanical converter 2 includes an actuator 30 and a drive unit 40, and the actuator 30 has the same configuration as that of the power generation unit 10 of the electromechanical converter 1. Also in the actuator 30, the positive charging regions 121 and the negative charging films 14 are alternately arranged in the circumferential direction on the upper and lower surfaces of the rotating member 12, respectively. It's misaligned. Moreover, the counter electrodes 15 and 16 of the actuator 30 are connected to the drive unit 40 through electric wirings. The electromechanical converter 2 uses the electrostatic force generated between the rotating member 12 and the counter electrodes 15 and 16 based on the electric signal input to the drive unit 40 to rotate the rotating member 12. A drive device (electret motor) that extracts power from electric power.

  The drive unit 40 is a circuit for driving the actuator 30 and includes a clock 41 and comparators 42 and 43. The drive unit 40 applies an alternating voltage whose polarity is alternately switched to the counter electrodes 15 and 16, and is generated between the charging region 121 and the charging film 14 of the rotating member 12 and the counter electrodes 15 and 16 of the fixed substrate 13. The rotating member 12 is rotated by the electrostatic force.

  As shown in FIG. 9, the output of the clock 41 is connected to the inputs of the comparators 42 and 43, the output of the comparator 42 is connected to the counter electrode 15, and the output of the comparator 43 is connected to the counter electrode 16 via electric wiring. Connected. The comparators 42 and 43 respectively compare the potential of the input signal from the clock 41 with the ground potential, and output the result as a binary value, but the output signals of the comparators 42 and 43 have opposite signs. When the input signal from the clock 41 is H, the counter electrode 15 has a potential of + V and the counter electrode 16 has a potential of −V. When the input signal is L, the counter electrode 15 has a potential of −V and the counter electrode 16 has a potential of + V. Become.

  When the actuator 30 is driven, the drive unit 40 applies a voltage having the same sign as the charging of the charging film 14 to one counter electrode 15, and applies a voltage having a sign different from the charging of the charging film 14 to the other counter electrode 16. Then, the signs of those voltages are alternately inverted. When the voltage is applied in this way, the electric field generated by the charging region 121 and the charging film 14 and the electric field generated by the counter electrodes 15 and 16 cause an interaction between the charging region 121 and the charging film 14 and the counter electrodes 15 and 16. Attraction or repulsion occurs between them. When the drive unit 40 applies an alternating voltage to the counter electrodes 15 and 16, a continuous force is applied to the rotating member 12, so that the rotating member 12 can be rotated.

  Even in the electromechanical transducer 2 having the actuator 30, the region 121 between the charged films 14 becomes a positive potential, and an electrostatic force is generated between the counter electrodes 15 and 16 there. For this reason, in the electromechanical converter 2, for example, the charging film 14 is formed only on the lower surface of the rotating member 12 (the surface facing the fixed substrate 13), and there is an actuator that does not correspond to the positive charging region 121. The generated driving force (rotational torque) is larger than in the example electromechanical transducer. In other words, the electromechanical converter 2 has an effect that a rotational torque having the same magnitude as that of the electromechanical converter of the comparative example can be obtained even when the applied voltage is lower than that of the electromechanical converter of the comparative example. . That is, since the electromechanical converter 2 can be driven with lower power consumption than the electromechanical converter of the comparative example, it is suitable for application to an electronic device such as a wristwatch that is driven by a battery having a small capacity.

  In the actuator 30 of the electromechanical converter 2, the rotating member 12 may be replaced with the rotating member 12 ′ in FIG. 6, or, like the power generation unit 10 ′ in FIG. A second fixed substrate having the counter electrodes 15 and 16 may be disposed on the opposite side to the above.

  FIGS. 10A to 10C are schematic configuration diagrams of still another electromechanical transducer 3. As shown in FIG. 10A, the electromechanical transducer 3 includes an actuator 50 and a drive unit 40. The actuator 50 includes a housing 51, a slide plate 52, a fixed substrate 53, a charging film 54, and counter electrodes 55 and 56. FIGS. 10B and 10C are plan views showing the arrangement of the counter electrodes 55 and 56 and the moving direction of the slide plate 52.

  The electromechanical transducer 3 reciprocates the slide plate 52 using an electrostatic force generated between the slide plate 52 and the counter electrodes 55 and 56 based on the electric signal input to the drive unit 40. Thus, the drive device extracts power from electric power. The movable member of the electromechanical transducer is not limited to the rotating member 12 of the electromechanical transducers 1, 1 ′, 2, but is slidably moved like the slide plate 52 of the electromechanical transducer 3. There may be.

  The slide plate 52 is an example of a movable member, and is made of a known substrate material such as a silicon substrate or a glass epoxy substrate, and is supported in the housing 51 by a movable support portion (not shown). Similarly to the rotating member 12, the material of the slide plate 52 is preferably a dielectric rather than a metal. The fixed substrate 53 is disposed on the bottom surface of the box-shaped casing 51. The slide plate 52 can reciprocate in a direction parallel to the fixed substrate 53 (horizontal direction, arrow A direction) while maintaining a certain distance from the fixed substrate 53.

  The charging film 54 is a thin film made of electret material and charged to the same polarity (for example, negative), extends in a direction orthogonal to the moving direction of the slide plate 52, and is arranged at equal intervals in the moving direction of the slide plate 52. It is composed of a plurality of strip-like (linear) regions. The charging film 54 is formed on the upper and lower surfaces of the slide plate 52 so as to be shifted from each other by one pitch (that is, alternately in the moving direction of the slide plate 52). If the polarity of the charging film 54 is negative, the material of the slide plate 52 is made of a dielectric material, so that the belt-like region 521 between the charge films 54 on the upper and lower surfaces of the slide plate 52 has The opposite positive charge is induced. Therefore, also in the actuator 50, on the upper and lower surfaces of the slide plate 52, the positive charging regions 521 and the negative charging films 54 are alternately arranged in the direction of the arrow A, and these arrangements are arranged on the upper and lower surfaces. Is shifted by one pitch.

  The counter electrodes 55 and 56 are each composed of a plurality of strip-like electrodes extending in a direction orthogonal to the moving direction of the slide plate 52, and are alternately formed on the upper surface of the fixed substrate 53 in the moving direction of the slide plate 52. It is preferable that the counter electrodes 55 and the counter electrodes 56 are arranged at equal intervals, and the widths thereof are the same. The width of the counter electrodes 55 and 56 is preferably the same as or substantially the same as the width of the charging film 54, and the number of the charging films 54, the number of the counter electrodes 55, and the counter electrode 56 on one side of the slide plate 52. The number is also preferably the same.

  The drive unit 40 is a circuit for driving the actuator 50, and is connected to the counter electrodes 55 and 56 via electric wiring. The drive unit 40 has the same configuration as that of the electromechanical converter 2 and applies a voltage whose polarity is alternately switched to the counter electrodes 55 and 56, so that the drive unit 40 in FIG. 10B and FIG. As shown, the slide plate 52 is slid in the horizontal direction (arrow A direction) within the housing 51.

  Even in the electromechanical transducer 3 having the actuator 50, the region 521 between the charged films 54 becomes a positive potential, and an electrostatic force is generated between the counter electrodes 15 and 16 there. Therefore, in the electromechanical converter 3, the charging film 54 is formed only on the lower surface of the slide plate 52 (the surface facing the fixed substrate 53), or the charging film 54 is the same in the arrow A direction on the upper and lower surfaces of the slide plate 52. The generated driving force is larger than in the case of an electromechanical transducer having an actuator formed at a position.

  In the actuator 50 of the electromechanical converter 3, a plurality of grooves for the charging film 54 are formed on the slide plate 52, the charging film 54 is formed so as to fill the grooves, and the charging film 54 is attached to the slide plate 52. The upper and lower surfaces may be flat surfaces free from unevenness due to the charging film 54 and the grooves. Further, like the power generation unit 10 ′ in FIG. 7, the counter electrodes 55 and 56 are arranged on the upper surface of the casing 51 so as to face the upper surface of the slide plate 52, and the counter electrodes 55 and 56 are also driven. The unit 40 may be electrically connected. Further, the drive unit 40 of the electromechanical converter 3 is replaced with the power storage unit 20 of the electromechanical converter 1, and the slide plate 52 is slid in the arrow A direction using the kinetic energy of the external environment. You may comprise the electric power generating apparatus which produces | generates static electricity by the electrostatic induction between the counter electrodes 55 and 56, and takes out electric power from motive power.

1, 1 ′, 2, 3 Electromechanical converter 10, 10 ′, 10 ″ Power generation unit 11, 11 ′ Rotating shaft 12, 12 ′ Rotating member 13, 17, 53 Fixed substrate 14, 54 Charged film 15, 16, 55, 56 Counter electrode 20 Power storage unit 30, 50 Actuator 40 Drive unit 52 Slide plate

Claims (9)

An electromechanical converter that performs conversion between electric power and power using electrostatic interaction between a charging unit and a counter electrode,
A fixed substrate;
A movable member movable with a fixed distance from the fixed substrate;
The first surface and the second surface are a first surface that is a surface facing the fixed substrate of the movable member and a second surface that is a surface opposite to the facing surface of the movable member. And a plurality of charged films that are alternately formed in the moving direction of the movable member and are charged to the same polarity.
A plurality of counter electrodes arranged in the moving direction on a surface of the fixed substrate facing the movable member;
A charge having a polarity opposite to that of the plurality of charged films is induced in a region between the charged films on the first surface and the second surface of the movable member, whereby the first surface and In the second surface, regions charged in opposite polarities are alternately arranged in the moving direction.
An electromechanical converter characterized by that.   The electromechanical transducer according to claim 1, wherein the movable member is made of a dielectric. The plurality of charged films satisfy a plurality of grooves formed alternately in the moving direction between the first surface and the second surface on the first surface and the second surface of the movable member. Is formed as
3. The electromechanical converter according to claim 1, wherein the first surface and the second surface of the movable member are flat surfaces that are free from unevenness due to the plurality of charging films and the plurality of groove portions. A second fixed substrate disposed on the opposite side of the fixed substrate across the movable member;
The electromechanical transducer according to any one of claims 1 to 3, wherein the plurality of counter electrodes are arranged in the moving direction also on a surface of the second fixed substrate facing the movable member. The movable member is rotatable about a rotation axis passing through a center of the movable member;
5. The electromechanical converter according to claim 1, wherein the plurality of charged films and the plurality of counter electrodes are arranged radially around the rotation axis. The movable member is a slide plate capable of reciprocating in a direction parallel to the fixed substrate;
5. The electromechanical converter according to claim 1, wherein each of the plurality of charged films and the plurality of counter electrodes has a strip shape extending perpendicularly to the moving direction. 6.   And a driving unit configured to apply a voltage whose polarity is alternately switched to the plurality of counter electrodes and move the movable member by an electrostatic force generated between the plurality of charged films and the plurality of counter electrodes. Item 7. The electromechanical converter according to any one of Items 1 to 6.   7. The power storage unit according to claim 1, further comprising a power storage unit that stores electric power generated by electrostatic induction between the plurality of charged films and the plurality of counter electrodes according to the movement of the movable member. The electromechanical transducer as described. A method of manufacturing an electromechanical converter that performs conversion between electric power and power using electrostatic interaction between a charging unit and a counter electrode,
The first surface of the substrate and the second surface that is the surface opposite to the first surface are spaced apart from each other so that the first surface and the second surface are staggered. Forming a plurality of thin film regions by an insulator; and
The plurality of thin films are grounded by disposing an electrode for discharge so as to face each of the plurality of thin film regions and discharging electrons from the discharge electrode toward the substrate by discharging. Charging the region simultaneously,
Arranging the substrate so as to face the fixed substrate so as to be movable with a fixed distance between the fixed substrate on which a plurality of counter electrodes are arranged, and
The charging step induces a charge having a polarity opposite to that of the plurality of thin film regions in a region between the thin film regions on the first surface and the second surface of the substrate. In the surface and the second surface, regions charged in opposite polarities are alternately formed.
The manufacturing method characterized by the above-mentioned.

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