JP5855434B2 - Electrostatic induction type electromechanical transducer - Google Patents

Description

  The present invention relates to an electrostatic induction type electromechanical transducer.

  As this type of device, one using an electret (injecting a charge into an insulating material such as a synthetic resin) is known (for example, JP-A-58-6118, JP-A-2001-177899, (See JP 2006-180450 A, JP 2007-298297 A, JP 2010-136598 A, etc.).

  This type of conventional device still has room for improvement in terms of durability and output. The present invention has been made to cope with such a problem.

<Configuration>
The electrostatic induction type electromechanical transducer of the present invention includes an electret, a first counter electrode, and a second counter electrode.

  The electret is a film-like or plate-like member made of a ferroelectric material. In this electret, the first region and the second region are alternately arranged so as to be adjacent to each other along the main surface direction. Here, the first region refers to a region where the polarization direction along the thickness direction (the direction defining the thickness of the electret) is the first direction. The second region refers to a region in which the polarization direction along the thickness direction is the second direction. The second direction is a direction opposite to the first direction. The main surface direction is a direction parallel to the main surface (a surface orthogonal to the thickness direction of the electret). In the first region or the second region, it is preferable that the polarization is formed substantially uniformly throughout the thickness direction.

  A plurality of the first regions and a plurality of the second regions may be provided so that the polarization direction is periodically reversed along the main surface direction. In this case, the inversion structure of the polarization direction may have a stripe shape with a period of 3 to 600 μm.

  The first counter electrode is provided to be relatively movable along the electret and the principal surface direction. This 1st counter electrode is arrange | positioned in the position corresponding to said 1st area | region or said 2nd area | region so that one of the pair of said main surfaces in the said electret may be opposed.

  The second counter electrode is provided so as to be relatively movable along the electret and the principal surface direction. The second counter electrode is disposed at a position corresponding to the first region or the second region so as to face the other one of the pair of main surfaces of the electret different from the one. .

  In the electrostatic induction electromechanical transducer of the present invention, typically, the first counter electrode is disposed at a position corresponding to the first region, while the second counter electrode is the first counter electrode. It is arranged at a position corresponding to the second region. Alternatively, the first counter electrode is disposed at a position corresponding to the first region and the second region, and the second counter electrode also corresponds to the first region and the second region. Placed in position.

  The electrostatic induction type electromechanical transducer of the present invention may further include a first counter substrate and a second counter substrate. In this case, the first counter substrate is disposed to face the one of the pair of main surfaces of the electret, and is provided to support the first counter electrode. The second counter substrate is disposed to face the other of the pair of main surfaces of the electret, and is provided to support the second counter electrode.

  The first counter substrate and the second counter substrate may be provided to be relatively movable along the main surface direction. Alternatively, the first counter substrate and the second counter substrate may be provided so as not to move relative to each other along the main surface direction.

<Action and effect>
In the electret according to the present invention, positive and negative charges are alternated in each adjacent region, so that the polarization state can be stably maintained for a long period of time. On the other hand, in the conventional ferroelectric electret disclosed in Japanese Patent Application Laid-Open No. 2007-298297 and the like, the polarization process is simply performed uniformly, and the same polarity is provided on the same side of the pair of main surfaces. Charge concentrates. For this reason, in such a conventional ferroelectric electret, the polarization structure becomes unstable due to repulsion between charges, and depolarization occurs.

  In the electrostatic induction electromechanical transducer of the present invention, since the electret has the configuration as described above, the electret is provided on the one side of the pair of main surfaces of the electret. The electromechanical conversion is performed by the first counter electrode, and the electromechanical conversion is also performed by the second counter electrode provided on the other side different from the one of the pair of main surfaces of the electret. Therefore, the output is improved as compared with the conventional device of this type.

It is sectional drawing which shows schematic structure of one Embodiment of the electrostatic induction type | mold electromechanical conversion element of this invention. It is a disassembled perspective view which shows an example of the specific structure of the electrostatic induction type | mold electromechanical conversion element shown by FIG. FIG. 3 is a partially exploded perspective view of the electrostatic induction type electromechanical transducer shown in FIG. 2. FIG. 4 is a perspective view showing an overall appearance of the electrostatic induction type electromechanical transducer shown in FIGS. 2 and 3. It is sectional drawing which shows schematic structure of the modification of the electrostatic induction type | mold electromechanical conversion element shown by FIG. It is sectional drawing which shows schematic structure of the other modification of the electrostatic induction type | mold electromechanical conversion element shown by FIG. It is sectional drawing which shows schematic structure of the other modification of the electrostatic induction type | mold electromechanical conversion element shown by FIG. It is sectional drawing which shows schematic structure of the other modification of the electrostatic induction type | mold electromechanical conversion element shown by FIG. It is sectional drawing which shows schematic structure of the other modification of the electrostatic induction type | mold electromechanical conversion element shown by FIG. It is sectional drawing which shows schematic structure of a part of other modification of the electrostatic induction type | mold electromechanical conversion element shown by FIG. It is sectional drawing which shows schematic structure of a part of other modification of the electrostatic induction type | mold electromechanical conversion element shown by FIG. It is sectional drawing which shows schematic structure of a part of other modification of the electrostatic induction type | mold electromechanical conversion element shown by FIG. It is sectional drawing which shows schematic structure of a part of other modification of the electrostatic induction type | mold electromechanical conversion element shown by FIG.

  Hereinafter, preferred embodiments of the present invention will be described using examples and comparative examples. In addition, the description about the following embodiment is specific to the extent possible, merely an example of the embodiment of the present invention in order to satisfy the description requirement (description requirement / practicability requirement) of the specification required by law. It is only what is described in.

  Therefore, as will be described later, it is quite natural that the present invention is not limited to the specific configurations of the embodiments and examples described below. Examples of various modifications that can be made to the present embodiment and examples (modifications) are inserted during the description of the embodiment, so that understanding of the description of the consistent embodiment is hindered. It is mainly listed at the end.

<Outline configuration>
FIG. 1 is a cross-sectional view showing a schematic configuration of an embodiment of the electrostatic induction type electromechanical transducer of the present invention. Referring to FIG. 1, an electrostatic induction-type electromechanical transducer 1 of the present embodiment is a power generation device (a electromechanical transducer that generates electricity by environmental vibration), and includes an electret 2, a first counter electrode 3, One counter substrate 4, a second counter electrode 5, a second counter substrate 6, a first output unit 7, and a second output unit 8 are provided.

  The electret 2 is a film-like or plate-like member made of a ferroelectric and has a plurality of first regions 21 and second regions 22. The first region 21 and the second region 22 are polarized so that components in the thickness direction of the polarization direction (z-axis direction in the figure) are opposite to each other. Here, the “thickness direction” is a direction that defines the “thickness” of the electret 2. That is, the “thickness direction” is a direction orthogonal to a pair of main surfaces (first main surface MS1 and second main surface MS2) that are surfaces parallel to the xy plane in the drawing of electret 2. Specifically, in the present embodiment, the first region 21 is polarized in one direction (z-axis positive direction in the drawing) parallel to the thickness direction. On the other hand, the second region 22 is polarized in another direction (z-axis negative direction in the figure) parallel to the thickness direction. Moreover, in the 1st area | region 21 and the 2nd area | region 22, polarization is formed substantially uniformly over the whole in the thickness direction.

  In the present embodiment, the electret 2 is provided so as to be capable of reciprocating in one direction (x-axis direction in the figure) in the main surface direction that is the creeping direction of the first main surface MS1 and the second main surface MS2. In the electret 2, the first region 21 and the second region 22 are adjacent to each other along the reciprocating direction of the electret 2 (the x-axis direction in the figure: the same as the “region arrangement direction” described later). Are arranged alternately. That is, the first region 21 and the second region 22 are long in a direction perpendicular to the above-described reciprocating direction and perpendicular to the thickness direction (hereinafter referred to as “electrode longitudinal direction”: y-axis direction in the figure). It has a direction, and is provided in a stripe shape such that the polarization direction is periodically reversed at a predetermined cycle (specifically, 3 to 600 μm) along the above-described reciprocating direction.

  The first counter electrode 3 is a thin wire-like conductive film formed along the above-described electrode longitudinal direction, and is provided to face the first main surface MS1. In the present embodiment, each of the plurality of first counter electrodes 3 is disposed at a position corresponding to each of the plurality of first regions 21. The plurality of first counter electrodes 3 are formed on a surface facing the first main surface MS1 in the first counter substrate 4 provided to face the first main surface MS1. The plurality of first counter electrodes 3 are coupled (electrically connected) to each other at the end portions in the electrode longitudinal direction.

  The second counter electrode 5 is a thin wire-like conductive film formed in the same manner as the first counter electrode 3 described above, and is provided to face the second main surface MS2. In the present embodiment, each of the plurality of second counter electrodes 5 is disposed at a position corresponding to each of the plurality of second regions 22. The plurality of second counter electrodes 5 are formed on a surface facing the second main surface MS2 in the second counter substrate 6 provided to face the second main surface MS2. The plurality of second counter electrodes 5 are coupled to each other at the end portions in the electrode longitudinal direction.

  In the present embodiment, the first counter substrate 4 and the second counter substrate 6 are fixed so as not to move relative to each other. That is, in the present embodiment, the electrostatic induction type electromechanical transducer 1 has the electret 2 in the region arrangement direction (the plurality of first regions 21 and the second regions) with respect to the first counter substrate 4 and the second counter substrate 6. The region 22 is arranged in the direction of arrangement (x-axis direction in the figure) to perform a mechanical-electrical conversion operation.

  The first output unit 7 includes a first output terminal 71 and a first ground side terminal 72. The first output terminal 71 is coupled (electrically connected) to the plurality of first counter electrodes 3. Similarly, the second output unit 8 includes a second output terminal 81 and a second ground side terminal 82. The second output terminal 81 is coupled to the plurality of second counter electrodes 5.

<Specific example>
FIG. 2 is an exploded perspective view showing an example of a specific configuration of the electrostatic induction type electromechanical transducer 1 shown in FIG. FIG. 3 is a partially exploded perspective view of the electrostatic induction type electromechanical transducer 1 shown in FIG. FIG. 4 is a perspective view showing the overall appearance of the electrostatic induction type electromechanical transducer 1 shown in FIGS. 2 and 3. Hereinafter, the details of the configuration of the electrostatic induction type electromechanical transducer 1 of this specific example will be described with reference to FIGS.

  The casing 110 of the electrostatic induction type electromechanical transducer 1 includes a guide member 111. The guide member 111 is a plate-like member made of insulating ceramics, supports the electret 2 so as to be reciprocable in the x-axis direction in the figure, and fixes the first counter substrate 4 and the second counter substrate 6 to each other. It is comprised so that it may support.

  Specifically, the guide member 111 is formed with an electret guide hole 111a, a first substrate support groove 111b, and a second substrate support groove 111c. The electret guide hole 111a is a through-hole formed along the thickness direction (z-axis direction in the figure) of the guide member 111, and guides the electret 2 so as to reciprocate in the x-axis direction in the figure. (See the arrows in FIG. 3).

  The first substrate support groove 111b is a groove formed on one surface (upper surface in the drawing) of the guide member 111 to a depth corresponding to the thickness of the first counter substrate 4, and the reciprocating direction of the electret 2 (X-axis direction in the figure) is provided. The first substrate support groove 111b is formed to such a depth that a predetermined gap is provided between the electret 2 and the first counter electrode 3 formed on the first counter substrate 4.

  The second substrate support groove 111c is a groove formed at a depth corresponding to the thickness of the second counter substrate 6 on the other surface (bottom surface in the drawing) of the guide member 111, and the reciprocating direction of the electret 2 (X-axis direction in the figure) is provided. Further, the second substrate support groove 111 c is formed to such a depth that a predetermined gap is provided between the electret 2 and the second counter electrode 5 formed on the second counter substrate 6.

  A first output terminal 71 is provided at one end of the first counter substrate 4 in the reciprocating direction of the electret 2 (x-axis direction in the drawing). Further, a stopper 112 is provided on the other end side of the first counter substrate 4 in the above-described reciprocating direction so as to be adjacent to the first counter substrate 4. The first counter substrate 4 is fitted in the first substrate support groove 111b so that the first output terminal 71 protrudes to one side (x-axis positive direction in the drawing) in the above-described reciprocating direction. The stopper 112 is a plate-like member made of insulating ceramics, and is disposed in the first substrate support groove 111b so as to contact the other end portion of the first counter substrate 4 described above.

  Similarly, a second output terminal 81 is provided at one end of the second counter substrate 6 in the reciprocating direction of the electret 2 (x-axis direction in the drawing). Further, a stopper 113 is provided on the other end side of the second counter substrate 6 in the above-described reciprocating direction so as to be adjacent to the second counter substrate 6. The second counter substrate 6 is fitted in the second substrate support groove 111c so that the second output terminal 81 protrudes to the other side (the negative x-axis direction in the drawing) in the above-described reciprocating direction. The stopper 113 is a plate-like member made of insulating ceramics, and is disposed in the second substrate support groove 111 c so as to contact the other end portion of the second counter substrate 6.

  That is, in this specific example, the first counter substrate 4 and the second counter substrate 6 are disposed such that the first output terminal 71 and the second output terminal 81 protrude in opposite directions.

  The guide member 111 is joined to a first cover plate 114 and a second cover plate 115 which are plate-like members made of insulating ceramics. The first cover plate 114 is provided on the first counter substrate 4 side. That is, the first counter substrate 4 is sandwiched between the guide member 111 and the first cover plate 114. Similarly, the second counter substrate 6 is sandwiched between the guide member 111 and the second cover plate 115.

<Action and effect>
In the electrostatic induction type electromechanical transducer element 1 (see FIGS. 1 to 4) of the present embodiment having such a configuration, the first counter substrate 4 and the second counter electrode 5 provided with the first counter electrode 3 include The electret 2 moves relative to the provided second counter substrate 6 in the above-described reciprocating direction (x-axis direction in the drawing). Due to such relative movement, fluctuations in charges induced in the first counter electrode 3 and the second counter electrode 5 occur. In this way, the mechanical energy of the relative movement is converted into electric energy (see JP 2010-136598 A, etc.).

  In this respect, in the electrostatic induction type electromechanical transducer 1 of the present embodiment, the first regions 21 and the second regions 22 whose polarization directions are reversed are arranged alternately along the region arrangement direction. For this reason, in the first main surface MS1 and the second main surface MS2, positive and negative charges are alternated for each adjacent region. Thereby, it becomes possible to hold | maintain the polarization state of the electret 2 stably for a long period of time. Therefore, according to the configuration of the present embodiment, it is possible to achieve better durability.

  From this point of view, if the arrangement period of the first region 21 and the second region 22 is too large, the size in the region arrangement direction of the first region 21 or the second region 22 becomes too large. The effect of stabilizing becomes smaller. On the other hand, it is difficult to stably (industrially) create a configuration in which the arrangement period of the first region 21 and the second region 22 is too small. Therefore, the inversion period of the polarization direction, that is, the arrangement period of the first region 21 and the second region 22 is preferably 3 to 600 μm.

  Moreover, in the electrostatic induction type electromechanical transducer 1 of the present embodiment, the first output unit is obtained by using the charges generated on both the first main surface MS1 side and the second main surface MS2 side of the electret 2. The output can be obtained by both the 7 and the second output unit 8. Therefore, according to such a configuration, the amount of conversion from the same mechanical energy to electrical energy is doubled.

  Thus, according to the configuration of the present embodiment, both good durability and high output in the electrostatic induction type electromechanical transducer 1 can be achieved.

<List of examples of modification>
It should be noted that the above-described embodiments and specific examples are merely examples of the realization of the present invention that the applicant considered to be the best at the time of filing of the present application, as described above. The invention should not be limited at all by the above-described embodiments and specific examples. Therefore, it goes without saying that various modifications can be made to the above-described embodiments and specific examples without departing from the essential part of the present invention.

  Hereinafter, some modifications will be exemplified. In the following description of the modification, components having the same configurations and functions as the components in the above-described embodiment are given the same name and the same reference numerals in this modification. And about description of the said component, description in the above-mentioned embodiment shall be used suitably in the range which is not inconsistent.

  However, it goes without saying that the modified examples are not limited to the following. The limited interpretation of the present invention based on the description of the above-described embodiment and the following modifications unfairly harms the interests of the applicant (especially rushing the application under the principle of prior application), but improperly imitates the imitator. It is beneficial and not allowed.

  It goes without saying that the configuration of the above-described embodiment and the configuration described in each of the following modifications can be combined in an appropriate manner within a technically consistent range.

  The present invention is not limited to the specific configuration described above. That is, it goes without saying that various modifications can be made to the above-described specific configuration within the scope of the present invention. For example, the shape and material of each member are not limited to the specific examples described above.

  As shown in FIG. 1, the first counter electrode 3 is disposed only at a position corresponding to the first region 21, while the second counter electrode 5 is disposed only at a position corresponding to the second region 22. In this case, the voltage waveform induced in the first counter electrode 3 and the voltage waveform induced in the second counter electrode 5 are substantially the same.

  Therefore, in this case, as shown in FIG. 1, the first output portion 7 on the first counter electrode 3 side having the first output terminal 71 and the first ground side terminal 72, the second output terminal 81, Instead of the configuration in which the second output portion 8 on the second counter electrode 5 side having the second ground side terminal 82 is separately provided, a configuration as shown in FIG. 5 can be adopted. In the configuration of the modification shown in FIG. 5, a first output terminal 71 connected to the plurality of first counter electrodes 3, a second output terminal 81 connected to the plurality of second counter electrodes 5, and In between, a load can be directly connected.

  In the configuration shown in FIGS. 1 to 4, the first counter substrate 4 and the second counter substrate 6 are fixed to the casing 110, and the electret 2 freely reciprocates. It was. However, the present invention is not limited to such a configuration. That is, as shown in FIG. 6, the first counter substrate 4 and the second counter substrate 6 may be reciprocally moved integrally, contrary to the above example.

  Further, the first output portion 7 on the first counter electrode 3 side having the first output terminal 71 and the first ground side terminal 72, the second counter electrode having the second output terminal 81 and the second ground side terminal 82. In the configuration in which the second output section 8 on the 5 side is provided separately, as shown in FIG. 7, the first counter substrate 4 and the second counter substrate 6 can be reciprocated separately. Also good. In this case, as shown in FIG. 8, the first counter substrate 4 side and the second counter substrate 6 side may have different natural frequencies. According to such a configuration, it is possible to perform a power generation operation widely corresponding to a change in the frequency of environmental vibration.

  The arrangement of the first counter electrode 3 and the second counter electrode 5 is not limited to the “alternate” state as shown in FIG. Specifically, for example, both the first counter electrode 3 and the second counter electrode 5 may be disposed only at positions corresponding to the first region 21.

  FIG. 9 is a cross-sectional view showing a schematic configuration of another modification of the electrostatic induction electromechanical transducer 1 shown in FIG. Referring to FIG. 9, on the first counter substrate 4, the first counter electrode 3 a disposed at a position corresponding to the first region 21 and the first counter electrode disposed at a position corresponding to the second region 22. Counter electrode 3b. Similarly, on the second counter substrate 6, a second counter electrode 5 a disposed at a position corresponding to the first region 21 and a second counter electrode 5 b disposed at a position corresponding to the second region 22. And are formed.

  Moreover, in this modification, the 1st output part 7 is provided with the 1st output terminal 71a, the 1st output terminal 71b, the 1st ground side terminal 72a, and the 1st ground side terminal 72b. The first output terminal 71a is coupled to the plurality of first counter electrodes 3a. The first output terminal 71b is coupled to the plurality of first counter electrodes 3b.

  Similarly, in the present modification, the second output unit 8 includes a second output terminal 81a, a second output terminal 81b, a second ground side terminal 82a, and a second ground side terminal 82b. . The second output terminal 81a is coupled to the plurality of second counter electrodes 5a. The second output terminal 81b is coupled to the plurality of second counter electrodes 5b.

  In such a configuration, the electrode density on the first counter substrate 4 and the second counter substrate 6 can be made as high as possible. Therefore, according to such a configuration, it is possible to further increase the output.

  As shown in FIGS. 10 to 12, an insulating first electrode cover layer 901 that covers the first counter electrode 3 may be provided on the first counter substrate 4 side. Similarly, an insulating second electrode cover layer 902 that covers the second counter electrode 5 may be provided on the second counter substrate 6 side. In addition, the 1st electrode cover layer 901 and the 2nd electrode cover layer 902 may be comprised from the same material, and may be comprised from a different material. Alternatively, only one of the first electrode cover layer 901 and the second electrode cover layer 902 may be formed depending on the installation mode of the electrostatic induction type electromechanical transducer 1.

  In this case, the first electrode cover layer 901 covers the entire surface of the surface (main surface) of the first counter substrate 4 on which the first counter electrode 3 is formed, as shown in FIG. It may be provided as a coating layer. Alternatively, as shown in FIG. 11, the first electrode cover layer 901 may be used as an insulating sheet or an insulating film interposed between the first counter electrode 3 and the electret 2 (see FIG. 1 and the like). The surface of the substrate 4 (main surface) may be provided in a state of “floating” from the surface on which the first counter electrode 3 is formed. Alternatively, the first electrode cover layer 901 may be provided only on the first counter electrode 3 as shown in FIG.

  Similarly, as shown in FIG. 10, the second electrode cover layer 902 covers the entire surface on which the second counter electrode 5 is formed on the surface (main surface) of the second counter substrate 6. It may be provided as a coating layer. Alternatively, as shown in FIG. 11, the second electrode cover layer 902 can be used as an insulating sheet or an insulating film interposed between the second counter electrode 5 and the electret 2 (see FIG. 1 and the like). The surface of the substrate 6 (main surface) may be provided in a “floating” state from the surface on which the second counter electrode 5 is formed. Alternatively, the second electrode cover layer 902 may be provided only on the second counter electrode 5 as shown in FIG.

  As shown in FIG. 13, the electret 2 may be formed with an insulating electret cover layer 903a that covers the first main surface MS1. Similarly, the electret 2 may be provided with an insulating electret cover layer 903b that covers the second main surface MS2. Note that only one of the electret cover layer 903a and the electret cover layer 903b may be formed depending on the installation mode of the electrostatic induction type electromechanical transducer 1.

  By adopting the configuration shown in at least one of FIGS. 10 to 13, the insulating state between the electret 2 and the first counter electrode 3 or the second counter electrode 5 can be ensured satisfactorily. . When the configurations of FIGS. 10 to 12 and the configuration of FIG. 13 are combined, the material constituting the first electrode cover layer 901 and / or the second electrode cover layer 902 and the electret cover layers 903a and 903b are configured. The material can be selected to be close on the triboelectric train.

  In addition, depending on the installation mode of the electrostatic induction type electromechanical transducer 1, instead of the configuration using the various cover layers described above, the first counter electrode 3 and / or the second counter electrode 5, the electret 2, A configuration in which a gel-like insulating material is filled in between may be employed.

  The present invention is not limited to the power generation element (mechanical / electrical conversion element that generates power by environmental vibration) as in the above-described example, and can also be used for a microphone, various sensors, etc. Changed as appropriate.) The vibration (relative movement) direction may also be the thickness direction. That is, the electret 2 may be movable relative to each electrode two-dimensionally or three-dimensionally.

  The first region 21 and the second region 22 may have the same or different widths in the region arrangement direction. Further, the first region 21 and the second region 22 do not have to be so-called “striped” in plan view as in the above-described examples. Specifically, for example, a so-called “checkered pattern” may be used in a plan view. Specifically, the first region 21 and the second region 22 having a substantially rectangular shape (typically a substantially square shape) in plan view may be alternately arranged two-dimensionally.

  The polarization direction may not be parallel to the thickness direction. That is, the angle α [°] formed between the polarization direction in the first region 21 and the positive z-axis direction is −45 ≦ α ≦ + 45, and is formed between the polarization direction in the second region 22 and the negative z-axis direction. The angle β may be such that [°] is −45 ≦ β ≦ + 45 (in this case, the absolute value of α may be the same as or different from the absolute value of β).

  Other modifications not specifically mentioned are naturally included in the technical scope of the present invention without departing from the essential part of the present invention.

  In addition, in each element constituting the means for solving the problems of the present invention, elements expressed functionally and functionally include the specific structures disclosed in the above-described embodiments and modifications, It includes any structure that can realize this action / function. Furthermore, the contents of the prior application and each publication (including the specification and the drawings) cited in the present specification may be incorporated as appropriate as part of the present specification.

DESCRIPTION OF SYMBOLS 1 ... Electrostatic induction type | mold electromechanical conversion element 110 ... Casing 111 ... Guide member 111a ... Electret guide hole 111b ... 1st board | substrate support groove | channel 111c ... 2nd board | substrate support groove | channel 112 ... Stopper 113 ... Stopper 114 ... 1st cover board 115 ... 2nd cover board 2 ... electret 21 ... 1st area | region 22 ... 2nd area | region 3 ... 1st counter electrode 3a ... 1st counter electrode 3b ... 1st counter electrode 4 ... 1st counter substrate 5 ... 2nd counter electrode 5a Second counter electrode 5b Second counter electrode 6 Second counter substrate 7 First output section 71 First output terminal 71a First output terminal 71b First output terminal 72 First ground terminal 72a 1st ground side terminal 72b ... 1st ground side terminal 8 ... 2nd output part 81 ... 2nd output terminal 81a ... 2nd output terminal 81b ... 2nd output terminal 82 ... 2nd ground side terminal 82a ... 2nd ground side terminal 82b ... second ground side terminal 901 ... first electrode cover layer 902 ... second electrode cover layer 903a ... electret cover layer 903b ... electret cover layer MS1 ... first main surface MS2 ... second main surface

JP 58-6118 A JP 2001-177899 A JP 2006-180450 A JP 2007-298297 A JP 2010-136598 A

Claims (9)

A first region whose polarization direction along the thickness direction is a first direction, and a second region whose polarization direction along the thickness direction is a second direction opposite to the first direction. And electrets made of ferroelectric films alternately arranged so as to be adjacent to each other along a principal surface direction that is a direction parallel to a principal surface that is a surface orthogonal to the thickness direction,
The electret is disposed at a position corresponding to the first region or the second region so as to face one of the pair of main surfaces, and moves relative to the electret along the main surface direction. A first counter electrode provided in a possible manner;
The electret and the main surface are arranged at positions corresponding to the first region or the second region so as to face the other one different from the one of the pair of main surfaces in the electret. A second counter electrode provided to be relatively movable along the direction;
Equipped with a,
The first region and the second region are formed on the electret which is a member that is continuous in the region arrangement direction of the first region and the second region. Inductive electromechanical transducer. The electrostatic induction type electromechanical transducer according to claim 1,
The first region or the second region in the electret is characterized in that polarization is formed substantially uniformly throughout the thickness direction.
Static induction type electromechanical transducer. The electrostatic induction type electromechanical transducer according to claim 1 or 2,
The first counter electrode is disposed at a position corresponding to the first region,
The second counter electrode is disposed at a position corresponding to the second region,
Static induction type electromechanical transducer. The electrostatic induction type electromechanical transducer according to claim 1 or 2,
The first counter electrode is disposed at a position corresponding to the first region and the second region,
The second counter electrode is arranged at a position corresponding to the first region and the second region,
Static induction type electromechanical transducer. In the electrostatic induction type electromechanical transducer according to any one of claims 1 to 4,
A first counter substrate disposed to face the one of the pair of main surfaces of the electret and provided to support the first counter electrode;
A second counter substrate disposed to face the other of the pair of main surfaces of the electret and provided to support the second counter electrode;
Further comprising:
Static induction type electromechanical transducer. The electrostatic induction type electromechanical transducer according to claim 5,
The first counter substrate and the second counter substrate are provided to be relatively movable along the principal surface direction.
Static induction type electromechanical transducer. The electrostatic induction type electromechanical transducer according to claim 5,
The first counter substrate and the second counter substrate are provided so as not to be relatively movable along the principal surface direction.
Static induction type electromechanical transducer. It is an electrostatic induction type electromechanical transducer according to any one of claims 1 to 7,
A plurality of the first regions and a plurality of the second regions are provided so that the polarization direction is periodically reversed along the main surface direction.
Static induction type electromechanical transducer. The electrostatic induction type electromechanical transducer according to claim 8,
The inversion structure of the polarization direction is a stripe shape with a period of 3 to 600 μm,
Static induction type electromechanical transducer.

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