Patent Translate Powered by EPO and Google Notice This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate, complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or financial decisions, should not be based on machine-translation output. DESCRIPTION JP2013051663 Abstract: To provide an acoustoelectric converter capable of changing the directivity characteristics according to the preference and use of a user with a simple configuration. An electrostatic speaker 1 includes a fixed electrode 10 and a fixed electrode 10 and a sheet-like vibrating member spaced apart from the fixed electrode 10 and 50, and a vibrating member 30 and a fixed electrode 10 and 50. It is provided with elastic members 20 and 40 having air permeability provided between them, and shape memory members 60A to 60H which are deformed to any one of a plurality of shape patterns predetermined by energization and maintain the shape after deformation. ing. When the shape memory members 60A to 60H are deformed, the electrostatic speaker 1 is deformed into any one of a concave surface shape, a planar shape, a convex surface shape, and a zigzag shape along with the deformation of the shape memory members 60A to 60H. . [Selected figure] Figure 1 Acoustoelectric converter [0001] The present invention relates to an acoustoelectric transducer. [0002] Loudspeakers known as electrostatic speakers (capacitor speakers) are known, and are noted in that they can be designed to be lightweight and compact. 11-05-2019 1 Here, an example of the configuration of the electrostatic speaker will be described. The electrostatic loudspeaker comprises two fixed electrodes facing each other across a gap and a sheet-like member (hereinafter referred to as a vibrator) having conductivity and supported so as not to contact the fixed electrode between the fixed electrodes. Configured When a predetermined voltage is applied between the fixed electrode and the vibrating body, a force that pulls the vibrating body toward one of the electrodes acts by the generated potential difference. On the other hand, when the direction of the voltage to be applied is reversed, a force in the reverse direction acts on the vibrating body, and the vibrating body moves in the reverse direction. As described above, the vibration state (such as the frequency and the amplitude) of the vibrator can be changed by appropriately applying a voltage to the electrode. Therefore, if the applied voltage value is changed according to the input signal, the vibrator is Is vibrated accordingly, and a sound wave corresponding to the input signal is generated from the vibrator. By forming the fixed electrode with a member having good sound wave permeability (for example, a metal plate provided with a large number of holes), the generated sound wave passes through the fixed electrode and is output as a sound to the outside of the speaker. [0003] By the way, in a so-called flat type speaker including an electrostatic type speaker, in order to generate a sound wave having a large vibration area and close to a plane wave due to its structure, control is performed to widen the directivity characteristics of the sound wave generated by the vibrator. It is known to be difficult to do. In addition, various techniques have been proposed for controlling directivity characteristics in a speaker. For example, Patent Document 1 proposes a technique for collecting a sound wave reflected by a reflector horn at a focal point by combining a spherical horn reflector horn and a speaker. Further, Patent Document 2 proposes a technology for causing acoustic vibration to converge at one point by using a curved acoustic vibration radiation plate. Further, according to Patent Document 3, a plurality of speakers are arranged in a spherical shape or on a plane, and by adjusting the delay amount and volume for outputting sound from each speaker, the sound output from each speaker is focused. There has been proposed a speaker reproducing apparatus capable of emitting sound. Further, Patent Document 4 proposes an electrostatic speaker that improves the directivity of a high range by using an accordion curtain-like diaphragm. In addition, in Patent Document 5, an electrostatic speaker having a diaphragm in which the diaphragm is bent in accordion pleats, and a plurality of flat electrodes in which fixed electrodes are inserted from the front and rear surfaces of the diaphragm into the fold thereof is disclosed. Proposed. Further, Patent Document 6 proposes a capacitor speaker which has flexibility and can be deformed into any of a concave surface shape, a planar shape, and a convex surface shape. Further, Patent Document 7 proposes an electrostatic type speaker which can be changed into a predetermined shape by energizing a shape memory member at the time of use, while making it possible to 11-05-2019 2 freely change the shape when not in use. [0004] JP-A 04-339494 JP-A 11-239394 JP-A 03-159500 JP-A 52-096610 JP-A 56-100600 JP-A 2007-58658 JP-A 2009-194442 Official gazette [0005] By the way, it is preferable if the directivity characteristic can be appropriately changed in the speaker in accordance with the preference and use of the user. In the technique described in Patent Document 1, since the spherical shell-like reflector horn is fixed, the directivity characteristic can not be changed. Further, even with the technique described in Patent Document 2, the directivity characteristic can not be changed because the shape of the acoustic vibration radiation plate is fixed. In the technique described in Patent Document 3, in order to change the directivity, it is necessary to provide a delay circuit or a gain adjustment circuit for each of the speakers constituting the speaker group to control the operation of each circuit. Could be cumbersome. Further, the speaker array requires many speaker units to form a wide-band sound field, which may be costly. Further, even with the techniques described in Patent Documents 4 and 5, the shape of the vibrating membrane is fixed in an accordion curtain shape (accordion pleat shape), and the directivity characteristic can not be changed. Further, in the technique described in Patent Document 6, it is necessary to provide a drive mechanism such as a motor to deform the speaker, which may make the device configuration complicated. Further, even with the technology described in Patent Document 7, the directivity characteristics can not be changed. Moreover, although it is also possible to use the structure of these speakers as a structure of a microphone, also in this case, it was not possible to change the directivity of the sound collection according to the user's preference or application. The present invention has been made in view of the above-described background, and it is an object of the present invention to provide an acousto-electric converter that can change the directivity characteristics according to the user's direction and application with a simple configuration. [0006] In order to solve the problems described above, according to the present invention, there is provided an electrode, a sheet-like vibrator having conductivity, which is spaced apart from the electrode, and a vent provided between the vibrator and the electrode. An elastic member having 11-05-2019 3 flexibility, fixed to at least one of the electrode and the elastic member, continuously performing energization and heating, and applying a force, any one of a plurality of shape patterns A shape memory member which is deformed to maintain the shape after deformation, and which has a shape different in shape depending on the mode of energization and heating and / or the manner of application of the force; There is provided an acoustoelectric transducer characterized in that the electrode, the vibrator and the elastic member are deformed with the deformation of a shape memory member. [0007] In a preferred aspect of the present invention, as the shape memory member is deformed, the electrode, the vibrator, and the elastic member have a concave surface shape in which the center is concaved in one direction, and the center in the one direction. May be deformed into at least one of a convex curved surface shape, a flat surface shape and a serpentine shape. [0008] In a further preferred aspect of the present invention, the shape memory member may be made of a plurality of shape memory alloys, and the shape may be changed depending on which of the plurality of shape memory alloys is energized. [0009] According to the present invention, in the acoustoelectric transducer, the directional characteristics can be changed according to the preference and the application of the user with a simple configuration. [0010] FIG. 1 is a schematic view of an electrostatic loudspeaker 1 according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the electrostatic speaker 1; FIG. 1 schematically shows the shape of an electrostatic speaker 1. 11-05-2019 4 FIG. 6 is a connection diagram showing a connection between shape memory members 60A to 60H and a power supply 80. FIG. 2 is a cross-sectional view of an electrostatic microphone 2; [0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the present embodiment, an example in which the acoustoelectric transducer is applied as an electrostatic speaker that converts an acoustic signal (electric signal) into a sound wave (sound) will be described. In the following description, sound and sound wave are used synonymously. FIG. 1 is a view schematically showing the appearance of an electrostatic speaker 1 according to an embodiment of the present invention, and FIG. 2 is a view schematically showing a cross section and an electrical configuration of the electrostatic speaker 1. . The electrostatic speaker 1 according to the present embodiment has a flexible structure in which the plane is rectangular and thin. The X, Y, and Z axes in these figures respectively indicate the longitudinal direction, the width direction, and the thickness direction of the electrostatic speaker 1. Moreover, the symbol in which "*" was described in "(circle)" in FIG. 2 has shown going to the front from the back of a drawing. The electrostatic loudspeaker 1 shown in FIGS. 1 and 2 is a socalled push-pull electrostatic loudspeaker having a rectangular flat fixed electrode 10 and a fixed electrode 50 provided substantially in parallel at a predetermined distance. The electrostatic speaker 1 has a vibrating body 30 sandwiched between the fixed electrode 10 and the fixed electrode 50 via a space. Between the fixed electrode 10 and the vibrating body 30 and between the fixed electrode 50 and the vibrating body 30, rectangular flat elastic members 20 and 40 having elasticity and air permeability are provided, respectively. 30 is movable to the fixed electrode 10 side and the fixed electrode 50 side. Both ends of the fixed electrode 10 and the fixed electrode 50 are fixed by a fixing member (not shown) made of an insulating material such as rubber. The fixing member is fixed to the fixed electrode 10 and the fixed electrode 50 using an adhesive or the like. The dimensions of the components such as the vibrator 30 and the fixed electrodes 10 and 50 in the drawing are different from the actual dimensions so that the shapes of the components can be easily understood. [0012] (Configuration of Electrostatic Loudspeaker 1) First, each part of the electrostatic loudspeaker 1 will be described. The fixed electrode 10 and the fixed electrode 50 are made of non-woven 11-05-2019 5 fabric in which a conductive material such as metal is deposited by sputtering. By making the non-woven fabric in this way, sound waves can pass through the gaps of the fibers of the nonwoven fabric. The fixed electrode 10 and the fixed electrode 50 may be formed of a non-woven fabric coated with a conductive dye. In addition, the fixed electrode 10 and the fixed electrode 50 may be formed of a warp having a conductivity and a conductive cloth formed by weaving a weft having a conductivity as well. In short, the fixed electrode 10 and the fixed electrode 50 may be made of materials having both conductivity, sound wave transmission (air permeability) and flexibility. Since the fixed electrode 10 and the fixed electrode 50 are made of flexible members that can be bent, they can be deformed into any shape, for example, a serpentine shape. [0013] The vibrating body 30 is a thin foil-like rectangular electrode. The vibrating body 30 is formed by depositing a conductive material such as metal on a film (thin film or sheet) using a polymer material such as PET (polyethylene terephthalate, polyethylene terephthalate), PP (polypropylene, polypropylene) or polyester. It is formed. Vibrator 30 may be formed of a material obtained by applying a conductive dye to a film. As described above, in the present embodiment, since the vibrating body 30 is also made of a flexible member that can be bent, it can be deformed into an arbitrary shape, for example, a zigzag shape. [0014] The elastic members 20 and 40 are made of a soft and air-permeable member, and may be, for example, a material obtained by compressing heat with a batt, and a synthetic resin in the form of a sponge or a non-woven cloth. It may be. Other members may be used as long as they are flexible and have insulation and sound transmission. In this embodiment, although the thing which has air permeability as an elastic member is used, an elastic member may not have air permeability and should just have insulation and sound permeability. Since the elastic members 20 and 40 are formed of flexible members that can be bent, they can be deformed into any shape, for example, a serpentine shape. In the present embodiment, the lengths of the elastic members 20 and 40 in the X and Y directions are longer than the lengths of the fixed electrode 10 in the X and Y directions, and the X and Y directions of the vibrating body 30 It is longer than the length of Further, the thicknesses (the heights in the Z direction) of the elastic member 20 and the elastic member 40 are the same. [0015] 11-05-2019 6 The shape memory members 60A to 60H are members in which the surface of a linear shape memory alloy is coated with a synthetic resin having insulation properties and heat resistance. The shape memory members 60A to 60H are disposed by adhering to the fixed electrode 10 with an adhesive, an adhesive tape, or the like. In this case, the shape memory members 60A, 60C, 60E, and 60G are disposed adjacent to each other, and are provided along one end of the fixed electrode 10 in the width direction. Shape memory members 60B, 60D, 60F, 60H are disposed adjacent to each other, and are provided along the other end of the fixed electrode 10 in the width direction. For example, when the fixed electrode 10 is a non-woven fabric or a conductive cloth, the shape memory members 60A to 60H may be attached by sewing to the fixed electrode. The point is that the shape memory members 60A to 60H may be fixed to the fixed electrode 10, and the shape change of the shape memory members 60A to 60H may be interlocked with the fixed electrode 10. The shape memory alloy of the shape memory members 60A to 60H is, for example, a shape memory alloy disclosed in Japanese Patent Application Laid-Open No. 200220848. [0016] When current flows, the shape memory members 60A to 60H increase in temperature due to Joule heat, shrink hard and deform into a memorized shape. On the other hand, when the energization of the shape memory members 60A to 60H is stopped, the temperature decreases, and the shape memory members 60A to 60H become soft and can be easily deformed. The shape memory members 60A and 60B in this embodiment store an arc shape such that the fixed electrode 10 side is inside the circle as shown in FIG. 3A. Shape memory members 60C and 60D store linear shapes, and shape memory members 60E and 60F store arc-like curved shapes such that the fixed electrode 10 side is outside the circle as shown in FIG. 3 (b). ing. As shown in FIG. 3C, the shape memory members 60G and 60H store so-called serpentine shapes in which peaks and valleys are alternately repeated. [0017] FIG. 4 is a connection diagram showing a connection relationship between shape memory members 60A to 60H and a power supply 80. As shown in FIG. As shown in FIG. 4, one end of each of the shape memory members 60A, 60C, 60E, and 60G is connected to the positive terminal of the power supply 80 through the switches 81A, 81B, 81C, and 81D, respectively. The other ends of shape memory members 60A, 60C, 60E and 60G are connected to one ends of 11-05-2019 7 shape memory members 60B, 60D, 60F and 60H respectively, and the other ends of shape memory members 60B, 60D, 60F and 60H are power supplies It is connected to the negative terminal of 80. The broken line shown in FIG. 4 shows the outer edge of the fixed electrode 10 when the electrostatic speaker 1 is placed on a flat and horizontal surface, and is disposed inside the outer edge of the conductors L used for the above-mentioned connection. The surface is covered with a synthetic resin having insulating properties and heat resistance, and is formed of a flexible material to such an extent that the flexibility of the electrostatic speaker 1 is not impaired. These lead wires are also fixed to the fixed electrode 10 by an adhesive, an adhesive tape or the like as in the shape memory members 60A to 60H. When the fixed electrode 10 is a non-woven fabric or a conductive cloth, the lead may be attached to the fixed electrode 10 by sewing. Further, the ends of the leads L connected to the switches 81A, 81B, 81C, 81D are arranged in a harness shape on the fixed electrode 10 and are connected to the terminals of the connector CN, via the connector CN. The switches 81A, 81B, 81C, 81D and the power supply 80 are connected. [0018] As shown in FIG. 2, the electrostatic speaker 1 includes a transformer 70, an input unit 71 to which an acoustic signal is input from the outside, and a bias power supply 72 which applies a DC bias to the vibrator 30. The bias power supply 72 is connected to the vibrating body 30 and the middle point on the output side of the transformer 70, and the two fixed electrodes 10 and 50 are connected to one end and the other end of the output side of the transformer 70, respectively. . The operation unit 83 is an operation unit that includes an operation element such as a button and outputs a signal according to the content operated by the user. The switch control unit 82 controls on / off of the switches 81A, 81B, 81C, and 81D in accordance with a signal output from the operation unit 83. The switch control unit 82 is an operation receiving unit that receives an operation for specifying a shape from the user, and the shape memory members 60A to 60C in a mode corresponding to the specified shape so that the shape corresponds to the received operation. It is a deformation ¦ transformation means which deform ¦ transforms shape memory member 60A-60H by supplying with respect to 60H. In addition, in FIG. 2, in order to prevent that a drawing becomes complicated, only shape memory member 60A, 60B is shown in figure, and illustration of shape memory members 60C-60H is abbreviate ¦ omitted. [0019] (Operation of Electrostatic Type Speaker 1) In the electrostatic type speaker 1, there is no 11-05-2019 8 conduction between the power source 80 and the shape memory member 60A when the switch 81A is off, and current flows from the power source 80 to the shape memory members 60A, 60B. Not flowing. Similarly, when the switch 81B is off, there is no conduction between the power supply 80 and the shape memory member 60C, and no current flows from the power supply 80 to the shape memory members 60C and 60D. Similarly, there is no conduction between the power supply 80 and the shape memory member 60E when the switch 81C is off, and no current flows from the power supply 80 to the shape memory members 60E, 60F, and the switch 81D is off when the switch 81D is off There is no conduction with the shape memory member 60G, and no current flows from the power supply 80 to the shape memory members 60G and 60H. Shape memory members 60A to 60H can be softened and freely deformed when no current flows. [0020] On the other hand, when the switch 81A is turned on, current flows from the power supply 80 to the shape memory members 60A, 60B, and when current flows in the shape memory members 60A, 60B, the temperature of the shape memory members 60A, 60B rises due to Joule heat, The storage members 60A and 60B are deformed into an arc-like curved shape such that the fixed electrode 10 side is inside the circle. Since the shape memory members 60A and 60B are fixed to the fixed electrode 10, the fixed electrodes 10 and 50, the elastic members 20 and 40, and the vibrator 30 (i.e., electrostatic speakers) along with the deformation of the shape memory members 60A and 60B. Both ends in the width direction of 1) are curved, whereby the entire electrostatic speaker 1 is curved. FIG. 3A schematically shows the shape of the electrostatic speaker 1 when the switch 81A is turned on. Since the shape memory members 60A and 60B are located along two sides in the longitudinal direction of the fixed electrode 10, when the shape memory members 60A and 60B are deformed in a curved shape, the electrostatic speaker 1 is shaped by human hands Even without preparation, it becomes a curved curved surface shape in the longitudinal direction. That is, when the switch 81A is turned on, the fixed electrodes 10 and 50, the vibrator 30, and the elastic members 20 and 40 are viewed from the front when the Z direction is the front as the shape memory members 60A and 60B are deformed. Deforms into a concave shape with a hollow center. [0021] When the switch 81B is turned on, current flows from the power supply 80 to the shape memory members 60C and 60D, and when current flows in the shape memory members 60C and 60D, the temperature of the shape memory members 60C and 60D rises due to Joule heat, and the shape The shapes of the storage members 60C and 60D are deformed. Since the shape memory 11-05-2019 9 members 60C and 60D are located along the both widthwise ends of the fixed electrode 10, when the shape memory members 60C and 60D are deformed in a straight line, the electrostatic speaker 1 is not shaped by human hands. Is a planar shape as illustrated in FIG. That is, with the deformation of the shape memory members 60C and 60D, the fixed electrodes 10 and 50, the vibrator 30, and the elastic members 20 and 40 are deformed into a planar shape. [0022] In addition, when the switch 81C is turned on, current flows from the power supply 80 to the shape memory members 60E and 60F, and the shape memory members 60E and 60F are curved in an arc shape such that the fixed electrode 10 side is outside the circle. Deform. FIG. 3B is a view schematically showing the shape of the electrostatic speaker 1 when the switch 81C is turned on. Since the shape memory members 60E and 60F are located along the widthwise ends of the fixed electrode 10, when the shape memory members 60E and 60F are deformed into a convex curve, both ends in the width direction of the electrostatic speaker 1 are curved. As a result, the electrostatic speaker 1 has a convex curved shape which is curved in the longitudinal direction. That is, with the deformation of the shape memory members 60E and 60F, the fixed electrodes 10 and 50, the vibrator 30, and the elastic members 20 and 40 have convex curved shapes in which the center is expanded as viewed from the front when the Z direction is the front. Transform into [0023] When the switch 81D is turned on, current flows from the power supply 80 to the shape memory members 60G and 60H, and the shape of the shape memory members 60G and 60H is deformed into a zigzag shape. FIG. 3C schematically shows the shape of the electrostatic speaker 1 when the switch 81D is turned on. Since the shape memory members 60G and 60H are positioned along the widthwise ends of the fixed electrode 10, when the shape memory members 60G and 60H are deformed into a serpentine shape, the electrostatic speaker 1 has a shape that is serpentine folded in the longitudinal direction. Become. That is, with the deformation of the shape memory members 60G and 60H, the fixed electrodes 10 and 50, the vibrator 30, and the elastic members 20 and 40 are deformed into a serpentine shape. As described above, in the present embodiment, as the shape memory members 60A to 60H are deformed, the fixed electrodes 10 and 50, the vibrator 30, and the elastic members 20 and 40 have a concave surface shape, a planar shape, a convex surface shape, and a serpentine shape. It deforms into one of the shapes. 11-05-2019 10 [0024] When an acoustic signal is input to the input unit 71 in a state in which the electrostatic speaker 1 is deformed, a voltage corresponding to the input acoustic signal is applied to the fixed electrodes 10 and 50 to which the bias voltage is applied. Thereby, the vibrating body 30 vibrates corresponding to the input signal. As a result, a sound wave corresponding to the input signal is generated, and the generated sound passes through the fixed electrodes 10 and 50 and is emitted to the outside of the electrostatic speaker 1. [0025] In the case where the electrostatic speaker 1 has a concave surface shape with respect to the Z direction in the drawing, the sound wave output from the electrostatic speaker 1 in the Z direction is focused and the sound wave propagates only in a narrow range. A sound field is formed which is less likely to cause sound leakage to the surroundings (sound waves are concentrated at the focal point). On the other hand, when the electrostatic speaker 1 has a planar shape, the sound wave output from the electrostatic speaker 1 has a strong rectilinearity, so that a sound field in which the sound propagates to a distance with little attenuation is formed ( Plane waves are generated). When the electrostatic speaker 1 has a convex curved surface shape in the Z direction, the sound wave output from the electrostatic speaker 1 in the Z direction is diffused, so the sound is propagated in a wide range (corresponding to the convex curved surface) Surface waves are generated). In the case where the electrostatic speaker 1 has a serpentine shape, air is compressed and pushed out in each of the serpentine concave portions, and the acoustic wave output from the electrostatic speaker 1 is more omnidirectional than the convex curved shape. A sound field close to (a curved wave close to a point sound source is generated). [0026] In this embodiment, by changing the shape of the electrostatic speaker 1 from a planar shape to a zigzag shape, it is possible to change from a narrow directional flat speaker to a wide directional speaker. Even in the case of the convex curved shape, the directivity is wide, but in the case of the convex curved shape, the width of the speaker is not so narrow because it is configured by only one convex curved surface, while the shape of the electrostatic speaker 1 is twisted. In the case of the shape, since the vibrating body is composed of a plurality of folds (that is, a plurality of convex curved surfaces and a concave curved surface), the speaker width can be 11-05-2019 11 significantly reduced. Further, in the case of the convex curved surface shape, the depth before and after the electrostatic speaker 1 is required to some extent, but in the case of the serpentine shape, the depth can be narrower than the convex curved surface shape. In addition, since the serpentine shape is a flat shape when viewed as a whole, it can be said that it is more stable than the curved shape. [0027] The user of the electrostatic loudspeaker 1 can select and use the shape of the electrostatic loudspeaker 1 according to his / her preference and application. Specifically, for example, when it is desired to use the electrostatic speaker 1 in a zigzag shape, the user performs an operation for turning on the switch 81D using the operation unit 83. The switch control unit 82 turns on the switch 81D according to the signal output from the operation unit 83, and when the switch 81D is turned on, the electrostatic speaker 1 is deformed into a serpentine shape as described above. [0028] Flat-shaped speakers are characterized by narrow directivity, but in some cases they may want to emit sound over a large area. Even in such a case, according to the present embodiment, one electrostatic speaker 1 realizes both a flat-shaped (narrow directivity) speaker and a zigzagshaped (wide directivity) speaker can do. As described above, according to the present embodiment, the user can use the electrostatic speaker 1 to realize directivity characteristics according to his or her preference and application without performing complicated operations. Moreover, in this embodiment, there is no need to separately provide a drive mechanism such as a motor for deforming the electrostatic speaker 1, and the device configuration can be simplified. [0029] [Modifications] Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and can be practiced in various other forms. For example, the above-described embodiment may be modified as follows to implement the present invention. (1) In the embodiment described above, although two power supplies are required for the bias power supply 72 and the power supply 80, voltage division is 11-05-2019 12 performed from the bias power supply 72, a current is supplied to the shape memory members 60A to 60H, and one power supply is provided. It may be In this configuration, if a current flows from the bias power supply 72 by the switch only when the electrostatic speaker 1 is used, the electrostatic speaker 1 is deformed into a predetermined shape only by turning on the electrostatic speaker 1. be able to. In addition, since no current flows in the shape memory members 60A to 60H in a state where the bias power supply 72 is not turned on and the electrostatic speaker 1 can not produce sound, deformation of the electrostatic speaker 1 is wasted when it is not caused to produce sound The power consumption can be reduced without causing the problem. [0030] (2) Further, in the present invention, the shapes of the fixed electrodes 10 and 50, the elastic members 20 and 40, and the vibrating body 30 are not limited to rectangles, and may be other shapes such as polygons, circles and ovals. It may be. Further, in the present invention, the whole of the electrostatic speaker 1 may be covered with a nonconductive and acoustically transparent member. [0031] When a conductive cloth is used as the fixed electrodes 10 and 50, the above-described shape memory alloy may be formed into a thread and woven into the fixed electrodes 10 and 50, and current may be supplied to the shape memory alloy thus made to be deformed. Good. [0032] (3) In the embodiment described above, the shape memory members 60A to 60H are positioned along two sides in the longitudinal direction (X direction in FIG. 1) of the fixed electrode 10. However, each side of the fixed electrode 10 (rectangle In the case (1), shape memory members may be arranged along the four sides). Further, the shape memory member may be disposed along two sides in the Y direction of the fixed electrode 10. In the embodiment described above, the shape memory members 60A to 60H are positioned along the respective sides of the fixed electrode 10. However, the shape memory members may be positioned along the diagonals of the fixed electrode 10 . 11-05-2019 13 [0033] Further, a plurality of shape memory members may be positioned between the fixed electrode 10 and the elastic members 20 and 40 in parallel with the shape memory members 60A to 60H. Further, the shape memory members 60A to 60H are arranged not only at the edge portion of the fixed electrode 10 but also at the edge portion of the fixed electrode 50 so that the electrostatic speaker 1 can be deformed using both surfaces of the electrostatic speaker 1 You may In addition, the shape memory members 60A to 60H may be disposed on both the elastic member 20 and the elastic member 40 or either of the elastic members 20 and 40 instead of the fixed electrodes 10 and 50. [0034] (4) In the embodiment described above, the electrostatic speaker 1 has been described as being deformed into a concave surface shape, a planar shape, a convex surface shape, or a serpentine shape, but the shape of the electrostatic speaker 1 Are not limited to those described above, but may be in other shapes. The point is that the fixed electrodes 10 and 50, the vibrator 30, and the elastic members 20 and 40 may be deformed into a plurality of shapes in accordance with the deformation of the shape memory member. [0035] (5) In the above embodiment, although a plurality of shape memory alloys are used as the shape memory members, the shape memory members are not limited to those described above, for example, they are deformed by applying a force, and the shape after deformation is maintained It may be a member. The point is that the shape memory member is a shape memory member that is deformed into any of a plurality of shape patterns and maintains the shape after deformation by at least one of continuously performing energization and heating and applying a force. Any shape may be used as long as it has a different shape depending on the mode of energization and heating and / or the manner of application of force. As a mode of energization, the shape may be made different depending on which of the plurality of shape memory alloys is energized. Moreover, as a mode of heating, for example, a plurality of bimetals that are deformed by a change in temperature may be used as a shape memory member, and the shape may be changed depending on which bimetal is heated. Also, for example, the shape may be changed by changing the temperature of heating. 11-05-2019 14 [0036] (6) Moreover, in the above-mentioned embodiment, the aspect in which the electrostatic loudspeaker 1 is a push-pull electrostatic loudspeaker has been described. However, the electrostatic speaker 1 may be a so-called single electrostatic speaker having only one fixed electrode. [0037] (7) In the embodiment and the modification described above, an example in which the acoustoelectric converter is applied to an electrostatic speaker that converts an acoustic signal (electric signal) into sound (sound) has been described. , And may be applied to electrostatic microphones that convert sound waves (sounds) into sound signals (electric signals). FIG. 5 is a diagram showing the electrical configuration of the electrostatic microphone 2 according to this modification. The configuration of the electrostatic microphone 2 shown in FIG. 5 is different from that of the electrostatic speaker 1 of FIG. 2 described above in that an output terminal 73 is provided instead of the input unit 71. In addition, the transformation ratio of the transformer 70 is adjusted suitably. [0038] When a sound is generated outside, the vibrating body 30 is vibrated by the sound, and the distance between the vibrating body 30 and the electrodes 10 and 50 changes according to the vibration. , 50 change in capacitance occurs. The change in capacitance causes a current to flow between the electrode 10 and the electrode 50, thereby providing a voltage output, that is, an acoustic signal. Then, this acoustic signal is supplied to the transformer 70, transformed by the transformer 70, and output to the output terminal 73. [0039] The electrostatic microphone 2 can also be deformed into various shapes as the electrostatic speaker 1 in the above-described embodiment. The user of the electrostatic microphone 2 can 11-05-2019 15 select and use the shape of the electrostatic microphone 2 in accordance with his / her preference and application. Specifically, for example, when it is desired to use the microphone 2 in a zigzag shape, the user performs an operation for turning on the switch 81D using the operation unit 83. The switch control unit 82 turns on the switch 81D according to the signal output from the operation unit 83, and when the switch 81D is turned on, the microphone 2 is deformed into a zigzag shape as in the above-described embodiment. [0040] DESCRIPTION OF SYMBOLS 1 ... electrostatic type speaker (acoustic electrical transducer), 2 ... electrostatic type microphone (electroacoustic transducer) 10, 50 ... fixed electrode, 20, 40 ... elastic member, 30 ... vibrating body, 60A, 60B, 60C 60D, 60E, 60F, 60G ... shape memory member, 70 ... transformer, 71 ... input unit, 72 ... bias power supply, 80 ... power supply, 81A, 81B, 81C, 81D ... switch, 82 ... switch control unit, 83 ... Operation unit 11-05-2019 16
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