JP6040545B2 - Electrostatic transducer - Google Patents

Description

  The present invention relates to an electrostatic transducer.

  As an electrostatic speaker (electrostatic transducer) that is flexible and can be bent, for example, there is an electrostatic speaker disclosed in Patent Document 1. In this electrostatic speaker, a polyester film in which aluminum is vapor-deposited is disposed between two cloths woven with conductive yarn, and ester wool is disposed between the film and the cloth.

JP 2008-54154 A

  The electrostatic speaker of Patent Document 1 is a push-pull electrostatic speaker, which supplies an audio signal to two cloths and a bias voltage to a vibrating film. In order to supply a bias voltage to the film, a bias voltage is supplied to the electrostatic speaker via a cable from a drive circuit that drives the electrostatic speaker. The cable and the electrostatic speaker are connected by a connector, but if the connector and the film are connected by solder, the film is made of polyester and the film may be damaged by the heat during soldering. is there.

  The present invention has been made under the background described above, and an object of the present invention is to provide a technique for suppressing damage to a component to which a signal is supplied in an electrostatic transducer.

In order to achieve the above object, the present invention provides a flexible electrode, a flexible vibrating body facing the electrode at a distance, an elasticity, and the electrode and the vibrating body. An elastic member disposed therebetween, a first conductor portion having conductivity, and a second conductor portion having conductivity, and an end portion of the first conductor portion and an end portion of the second conductor portion are A flexible substrate arranged side by side, a flexible adhesive between the surface of the electrode and the first conductor part, and a conductive material between the vibrator and the second conductor part. and a bonding agent having the ends of the front SL end of the first conductor portion and the second conductor section, and wherein the electrode is positioned outside the edge of the vibrating body and the elastic member An electrostatic transducer is provided.

  In this invention, it is good also as a structure provided with two or more said flexible substrates.

  In the present invention, the electrostatic transducer may have a shape having a plurality of sides when viewed from the electrode side and includes at least one flexible substrate corresponding to each side.

  Moreover, in this invention, it is good also as a structure provided with the frame which has a connector which is arrange | positioned at the edge of the said electrostatic transducer and the edge part of a said 1st conductor part and the edge part of the said 2nd conductor part are fitted.

In the present invention, the second elastic member having elasticity, which is located on the opposite side to the elastic member when viewed from the vibrating body, and the opposite side from the vibrating body when viewed from the second elastic member And the second electrode having flexibility, and the flexible substrate includes a third conductor portion having conductivity, the end portion of the first conductor portion, and the second conductor portion of the second conductor portion. end of said end portion and said third conductor portion are arranged side by side, have an adhesive having conductivity lies between said surface and said third conductor portion of the second electrode, disposed base parallel The end portion of the first conductor portion, the end portion of the second conductor portion, and the end portion of the third conductor portion are the electrode, the second electrode, the vibrating body, the elastic member, and the first member. It is good also as a structure located outside the edge of 2 elastic members.

  ADVANTAGE OF THE INVENTION According to this invention, damage to the components to which a signal is supplied in an electrostatic transducer can be suppressed.

1 is an external view of an electrostatic speaker 1 according to an embodiment of the present invention. FIG. 3 is an exploded view of the electrostatic speaker 1. The top view and sectional drawing of the flexible substrate 70. FIG. FIG. 2 is a top view of the electrostatic speaker 1. BB sectional drawing of FIG. CC sectional view taken on the line of FIG. FIG. 3 is a diagram showing a configuration of a drive circuit 100. The top view of the electrostatic speaker 1 which concerns on a modification. The top view of the electrostatic speaker 1 which concerns on a modification. FIG. 3 is a perspective view of an electrostatic speaker 1 including a frame 2. The top view of the electrostatic speaker 1 which concerns on a modification. The figure which showed the structure of the acoustic signal generation circuit.

[Embodiment]
FIG. 1 is an external view of an electrostatic speaker 1 as an example of an electrostatic electroacoustic transducer (electrostatic transducer) according to an embodiment of the present invention, and FIG. 2 is an exploded view of the electrostatic speaker 1. FIG. In the figure, directions are shown by orthogonal X-axis, Y-axis, and Z-axis. When the electrostatic speaker 1 is viewed from the front, the left-right direction is the X-axis direction, the depth direction is the Y-axis direction, and the up-down direction. The direction is the Z-axis direction. In the following description, for convenience of description, the positive direction side of the Z axis may be referred to as the upper surface side, and the negative direction side of the Z axis may be referred to as the lower surface side. In addition, the dimension of each member in the drawing is different from the actual dimension so that the shape and positional relationship of each member can be easily understood.

As shown in the figure, the electrostatic speaker 1 includes a vibrating body 10, electrodes 20U and 20L, elastic members 30U and 30L, protection members 60U and 60L, and a flexible substrate 70. In addition, illustration of the flexible substrate 70 is abbreviate | omitted in FIG.
In the present embodiment, the configurations of the electrode 20U and the electrode 20L are the same, and the configurations of the elastic member 30U and the elastic member 30L are the same. For this reason, in these members, when there is no particular need to distinguish between a member having a suffix “U” and a member having a suffix “L”, description of “L” and “U” is omitted. . Further, the configurations of the protection member 60U and the protection member 60L are the same. For this reason, also in these members, when there is no particular need to distinguish between members having the suffix “U” and members having the suffix “L”, description of “L” and “U” is omitted. To do.

(Configuration of each part of the electrostatic speaker 1)
First, each part constituting the electrostatic speaker 1 will be described. When viewed from the upper surface side, the rectangular vibrating body 10 is electrically conductive on one surface of a synthetic resin film (insulating layer) having insulating properties and flexibility such as PET (polyethylene terephthalate) or PP (polypropylene). It has a sheet-like configuration in which a conductive metal (conductive layer) is formed by vapor-depositing a conductive metal. In the present embodiment, the conductive film is formed on one surface of the film, but may be formed on both surfaces of the film. The vibrating body 10 may have a configuration in which a conductive metal is rolled into a film shape.

  The elastic member 30 is a non-woven fabric in the present embodiment, and can pass air and sound without conducting electricity, and its shape is rectangular when viewed from the upper surface side. The elastic member 30 has elasticity, and is deformed when a force is applied from the outside, and returns to its original shape when the force applied from the outside is removed. The elastic member 30 may be any member that has insulating properties, allows sound to pass through, and has elasticity. The elastic member 30 is formed by applying heat to a batting and compressing it, a woven cloth, a synthetic resin having insulating properties, and the like. It may be the one that was made. Further, the elastic member 30 may be configured such that air does not pass as long as sound passes. For example, the elastic member 30 may be formed by forming a discontinuous bubble sponge having elasticity into a sheet shape. In the present embodiment, the length of the elastic member 30 in the X-axis direction is longer than the length of the vibrating body 10 in the X-axis direction, and the length of the elastic member 30 in the Y-axis direction is longer than the length of the vibrating body 10 in the Y-axis direction. Although it is long, it is not limited to this configuration.

  The electrode (fixed electrode) 20 is made of an insulating synthetic resin film (insulating layer) such as PET or PP, and a conductive metal (conductive layer) is deposited on one surface of the film by depositing a conductive metal. ). The electrode 20 is rectangular when viewed from the upper surface side. The electrode 20 has a plurality of holes penetrating from the front surface to the back surface, and allows passage of air and sound. In addition, illustration of this hole is abbreviate | omitted in drawing. In the present embodiment, the length of the electrode 20 in the X-axis direction and the length in the Y-axis direction are the same as those of the vibrating body 10. Similarly to the vibrating body 10, the electrode 20 may have a conductive film formed on both surfaces of the film, or may be a film formed by rolling a conductive metal.

  The protection member 60 is an insulating cloth. The protection member 60 has a rectangular shape when viewed from the upper surface side, and allows passage of air and sound. In the present embodiment, the length in the X-axis direction and the length in the Y-axis direction of the protection member 60 are the same as those of the elastic member 30. The protective member 60 only needs to have insulating properties, and may be, for example, a synthetic resin sheet.

  The sheet-like flexible substrate 70 is a flexible and bendable substrate. 3A is a view of the flexible substrate 70 as viewed from the upper surface side, and FIG. 3B is a cross-sectional view taken along line AA in FIG. The flexible substrate 70 includes conductive portions 701 to 703 that are conductive thin films (for example, copper) and insulating synthetic resin (for example, polyimide) films 704 and 705. Each of the conductor parts 701 to 703 is roughly divided into a strip-like adhesive part 70A and a lead part 70B connected to the adhesive part 70A. The conductor portions 701 to 703 are arranged so that the long sides of the strip-shaped adhesive portion 70A are parallel to each other. The lead portions 70B of the conductor portions 701 to 703 are formed so as to be narrower than the adhesive portion 70A when viewed from the upper surface side, and the long sides of the strip portions are parallel to each other.

The film 704 is bonded to the upper surface side of the conductor portions 701 to 703. The portion of the film 704 that contacts the bonding portion 70A of the conductor portions 701 to 703 has a band shape, the length is longer than the long side of the bonding portion 70A, and the width is wider than the short side of the bonding portion 70A. Note that a gap is provided between each band-like portion. For this reason, each conductor part can be bent separately. Further, the portions of the film 704 that contact the lead portions 70B of the conductor portions 701 to 703 are formed so that the end portions of the lead portions 70B are exposed.
The film 705 is bonded to the lower surface side of the lead portion 70B of the conductor portions 701 to 703. The film 705 is formed to have a larger area than the region where the lead portions 70B of the conductor portions 701 to 703 are seen from the bottom surface side so that the lead portions 70B of the conductor portions 701 to 703 are not exposed to the lower surface side. ing.

(Structure of electrostatic speaker 1)
Next, the structure of the electrostatic speaker 1 will be described. 4 is a top view of the electrostatic speaker 1, and FIG. 5 is a cross-sectional view taken along the line BB of FIG. The electrostatic speaker 1 of the present embodiment has a rectangular shape when viewed from the upper surface side (a shape when viewed in plan). In the electrostatic speaker 1, the vibrating body 10 is disposed between the lower surface side of the elastic member 30U and the upper surface side of the elastic member 30L, with the conductive film side being the upper surface side. The vibrating body 10 is coated with an adhesive with a width of several millimeters from the edge to the inside and adhered to the elastic member 30U and the elastic member 30L, and the inside of the portion where the adhesive is applied is elastic with the elastic member 30U. The member 30L is not fixed. The elastic member 30U and the elastic member 30L are also fixed to each other by applying an adhesive with a width of several millimeters from the edge to the inside.

  The electrode 20U is bonded to the upper surface side of the elastic member 30U. The electrode 20L is bonded to the lower surface side of the elastic member 30L. The electrode 20U is adhesively applied to the elastic member 30U with a width of several mm inward from the edge, and the electrode 20L is elastically applied to the elastic member 30U with a width of several mm inward from the edge. It is glued to. The inside of the electrode 20 is not fixed to the elastic member 30 from the portion where the adhesive is applied. The electrode 20U is disposed such that the side with the conductive film is the upper surface side, and the electrode 20L is disposed so that the side with the conductive film is the upper surface side. That is, the conductive film of each electrode is on the upper surface side.

  The protection member 60U is bonded to the upper surface side of the electrode 20U. The protective member 60L is bonded to the lower surface side of the electrode 20L. The protective member 60U is adhesively applied to the elastic member 30U with a width of several mm inward from the edge, and the protective member 60L is elastic with adhesive applied to the elastic member 30U with a width of several mm inward from the edge. It is bonded to the member 30L. The protective member 60 is in a state where the inner side of the part where the adhesive is applied is not fixed to the electrode 20.

  Next, the arrangement of the flexible substrate 70 will be described. 6 is a cross-sectional view taken along the line CC of FIG. The flexible substrate 70 has an adhesive portion 70 </ b> A located inside the electrode 20 and a lead portion 70 </ b> B located outside the electrode 20 as viewed from the upper surface side. Further, as shown in FIG. 6, the flexible substrate 70 has the conductor portion 701 on the upper surface side of the electrode 20U (side with the conductive film), the conductor portion 702 on the upper surface side of the vibrating body 10 (side with the conductive film), The conductor part 703 is located on the upper surface side (side with the conductive film) of the electrode 20L. The conductor portion 701 is bonded to the conductive film of the electrode 20U with a conductive adhesive, the conductor portion 702 is bonded to the conductive film of the vibrating body 10 with a conductive adhesive, and the conductor portion 703 is conductive. It is bonded to the conductive film of the electrode 20L with an adhesive having

(Electrical configuration of the electrostatic speaker 1)
Next, an electrical configuration relating to the electrostatic speaker 1 will be described. FIG. 7 is a diagram showing the configuration of the drive circuit 100 that drives the electrostatic speaker 1. As shown in FIG. 7, the driving circuit 100 for driving the electrostatic speaker 1 includes an amplifying unit 130, a transformer 110, a bias power supply 111, resistors R11 to R13, a diode D1, and a first connector for a flexible substrate. 140.

  The amplifying unit 130 is an amplifying unit that amplifies and outputs an input acoustic signal. The amplifying unit 130 is connected to the terminals T14 and T15 of the primary side coil of the transformer 110 via the resistors R11 and R12. The AC acoustic signal amplified by the amplifying unit 130 is supplied to the transformer 110. The transformer 110 boosts the acoustic signal supplied from the amplification unit 130. One terminal T11 of the secondary coil of the transformer 110 is connected to the first terminal of the first connector 140, and the other terminal T12 of the secondary coil of the transformer 110 is the fifth terminal of the first connector 140. It is connected to the. The center tap T13 of the secondary coil of the transformer 110 is connected to the ground GND that is the reference potential of the drive circuit 100.

  The bias power supply 111 generates a DC signal for applying a bias voltage to the vibrating body 10. The DC signal output from the bias power supply 111 is supplied to the third terminal of the first connector 140 through the diode D1 and the resistor R13. Note that the second and fourth terminals of the first connector 140 are connected to the ground GND of the drive circuit 100.

  The lead portion 70 </ b> B of the flexible substrate 70 is fitted into the first connector 140. When the lead portion 70B is fitted to the first connector 140, the end portion of the conductor portion 701 exposed on the upper surface side of the lead portion 70B comes into contact with the first terminal of the first connector 140. In addition, the end portion of the conductor portion 702 is in contact with the third terminal of the first connector 140, and the end portion of the conductor portion 703 is in contact with the fifth terminal of the first connector 140. Thereby, the terminal T11 is electrically connected to the electrode 20U via the conductor portion 701, and the bias power source 111 is electrically connected to the vibrating body 10 via the diode D1, the resistor R13, and the conductor portion 702. The terminal T12 is connected to the electrode 20L through the conductor portion 703.

(Operation of the embodiment)
Next, the operation of this embodiment will be described. When the lead-out portion 70B of the flexible substrate 70 is fitted into the first connector 140, the bias power supply 111 is electrically connected to the vibrating body 10 via the diode D1 and the resistor R13, and a predetermined DC bias voltage is vibrated. Applied to the body 10. Here, when the amplitude of the acoustic signal input to the amplifying unit 130 is 0V, since the center tap T13 of the transformer 110 is connected to the ground GND, the voltage at the terminal T11 and the terminal T12 is 0V.

  When an AC acoustic signal is input to the amplifying unit 130, the input acoustic signal is amplified and supplied to the primary side of the transformer 110. The acoustic signal boosted by the transformer 110, which is a boosting means, and output from the terminal T12 has the same amplitude as the acoustic signal boosted by the transformer 110 and output from the terminal T11, and the polarity of the signal is reversed.

  When a positive acoustic signal is input to the amplifying unit 130, the polarity of the acoustic signal output from the secondary terminal T11 of the transformer 110 becomes positive, and the polarity of the acoustic signal output from the terminal T12 becomes negative. In this case, the electrostatic attractive force between the vibrating body 10 and the electrode 20U is weakened, while the electrostatic attractive force between the vibrating body 10 and the electrode 20L is increased. Then, the vibrating body 10 is displaced to the electrode 20L side (the negative direction of the Z axis) according to the difference between the electrostatic attractive force acting on the electrode 20U side and the electrostatic attractive force acting on the electrode 20L side.

  Further, when a negative acoustic signal is input to the amplifying unit 130, the polarity of the acoustic signal output from the secondary terminal T11 of the transformer 110 becomes negative, and the polarity of the acoustic signal output from the terminal T12 becomes negative. When it becomes positive, the electrostatic attractive force between the vibrating body 10 and the electrode 20L is weakened, while the electrostatic attractive force between the vibrating body 10 and the electrode 20U is increased. Then, the vibrating body 10 is displaced to the electrode 20U side (the positive direction of the Z axis) according to the difference between the electrostatic attractive force acting on the electrode 20U side and the electrostatic attractive force acting on the electrode 20L side.

  Thus, the vibrating body 10 is displaced in the positive direction of the Z-axis and the negative direction of the Z-axis in accordance with the acoustic signal, and becomes a vibration by sequentially changing the displacement direction, and the vibration state (frequency, amplitude, A sound wave corresponding to the phase is generated from the vibrating body 10. The generated sound wave is radiated as sound to the outside of the electrostatic speaker 1 through the elastic member 30 having acoustic transparency, the electrode 20 and the protective member 60.

  In the present embodiment, various signals from the drive circuit 100 are supplied to the electrode 20 and the vibrating body 10 via the flexible substrate 70. Since the conductor portions 701 to 703 of the flexible substrate 70 are electrically connected to the electrode 20 and the vibrating body 10 with a conductive adhesive, the electrostatic type can be easily performed without damaging the electrode 20 and the vibrating body 10 due to heat. The speaker 1 can be assembled. Further, since the lead-out portion 70B of the flexible substrate 70 is fitted into the first connector 140 for the flexible substrate, the electrostatic speaker 1 and the drive circuit 100 can be easily connected. Moreover, since the vibrating body 10, the electrode 20, the elastic member 30, and the protective member 60 constituting the electrostatic speaker 1 are all formed in a thin sheet shape, they can be freely bent. Further, since the flexible substrate 70 can be bent, the electrostatic speaker 1 can be radiated with a curved surface.

[Modification]
As mentioned above, although embodiment of this invention was described, this invention is not limited to embodiment mentioned above, It can implement with another various form. For example, the present invention may be implemented by modifying the above-described embodiment as follows. In addition, you may combine each of embodiment mentioned above and the following modifications.

In the embodiment described above, the shape of the portion of the conductor portions 701 to 703 bonded to the electrode 20 or the vibrating body 10 is a band shape, but the shape of this portion is not limited to the band shape. For example, as long as it is a sheet shape, other shapes such as a circle and a polygon may be used.
In the above-described embodiment, the strip portions bonded to the electrode 20 and the vibrating body 10 in the conductor portions 701 to 703 are parallel to each other, but the shape of the flexible substrate 70 is limited to this configuration. It is not a thing. For example, the structure provided with the conductor parts 701-703 radially from the drawer | drawing-out part 70B may be sufficient.

In the embodiment described above, the flexible substrate 70 is disposed at the center portion in the X-axis direction when viewed from the upper surface side, but the position of the flexible substrate 70 is not limited to this position. For example, as shown in FIG. 8, it may be arranged at a position close to the side along the Y axis as viewed from the upper surface side.
In the above-described embodiment, the number of flexible substrates 70 is one, but the number of flexible substrates 70 is not limited to one. For example, as shown in FIG. 9, a plurality of flexible boards 70 may be provided. In FIG. 9, four flexible boards 70 are provided, but the number of flexible boards 70 may be two, three, or five or more.

  In the above-described embodiment, as shown in FIG. 10, the edge of the electrostatic speaker may be sandwiched between the groove portions of the rod-shaped metal or resin frame 2. In addition, the 1st connector for flexible substrates may be arrange | positioned inside the frame 2, and a 1st connector and a drive circuit may be connected with a cable. In FIG. 10, the frame 2 is provided on two sides of the electrostatic speaker 1 facing each other, but the frame 2 may be provided on four sides.

  In the embodiment described above, the lead-out portion 70B of the flexible substrate 70 protrudes outside the protective member 60 and the elastic member 30 when viewed from the upper surface side, but the arrangement position of the flexible substrate 70 is limited to this configuration. It is not a thing. For example, as shown in FIG. 11, a groove-shaped notch may be provided in the protective member 60 and the elastic member 30, and the drawer portion 70B may be located at this position.

  In the embodiment described above, the elastic member 30 may be disposed on the electrode 20U, and a film including a conductive film may be disposed on the elastic member 30. In this configuration, the number of conductor portions in the flexible substrate 70 is four. One of the four conductor portions is bonded to the conductive film of the film, and the conductor portion is electrically connected to the ground GND of the drive circuit. According to this configuration, even if the protection member 60 is broken, the human body does not contact the electrode 20U, and current can be prevented from flowing from the electrostatic speaker 1 to the human body. Note that the elastic member 30 may be disposed under the electrode 20L, a film including a conductive film may be disposed on the elastic member 30, and the conductor portion may be bonded to the film.

  In the above-described embodiment, the electrostatic speaker 1 is a push-pull type, but the electrostatic speaker may be a single-type electrostatic speaker that vibrates the vibrating body 10 with one electrode 20. In the case of a single type, the flexible substrate 70 has two conductor portions.

  In the embodiment described above, the conductive portion is bonded to the electrode 20 and the vibrating body 10 with a conductive adhesive, but the conductive portion is bonded to the electrode 20 and the vibrating body 10 with a conductive adhesive tape. It may be.

  In the embodiment described above, the electrostatic speaker 1 has a rectangular shape when viewed from the upper surface side, but may have another shape such as a polygon, a circle, or an ellipse.

In the above-described embodiment, the configuration in which the flexible substrate 70, the electrode 20, the vibrating body 10, and the elastic member 30 are stacked is a speaker that converts an acoustic signal into sound, but this configuration converts sound into an acoustic signal. An electrostatic microphone (electrostatic transducer) can also be used.
FIG. 12 is a diagram illustrating a configuration of the microphone 2 according to the present modification and an acoustic signal generation circuit 200 that generates an acoustic signal representing the sound collected by the microphone 2. In the present modification, the microphone 2 has the same configuration as that of the electrostatic speaker 1 described above. Therefore, the members constituting the microphone 2 are denoted by the same reference numerals as those of the electrostatic speaker 1 and the description thereof will be given. Is omitted. The configuration of the acoustic signal generation circuit 200 is the same as that of the drive circuit 100 except that the direction in which the signal flows is different from that of the drive circuit 100. Therefore, the components included in the acoustic signal generation circuit 200 are the components included in the drive circuit 100. The same reference numerals are given and description of each component is omitted. In addition, the transformation ratio of the transformer 110 and the resistance values of the resistors R11 to R13 are adjusted as appropriate.

The electrode 20 which is a conductor and the vibrating body 10 which is a conductor face each other at a distance, and the electrode 20 and the vibrating body 10 function as a capacitor constituted by a parallel plate conductor. Since a bias voltage is applied to the vibrating body 10, a constant charge is accumulated in the capacitor when no sound reaches the microphone.
When sound reaches the microphone 2, the vibrating body 10 vibrates due to the reached sound. When the vibrating body 10 vibrates, the distance between the vibrating body 10 and the electrodes 20U and 20L changes, so that the capacitance between the vibrating body 10 and the electrode 20 changes.

For example, when the vibrating body 10 is displaced toward the electrode 20U, the distance between the electrode 20U and the vibrating body 10 is shortened, and the capacitance between the electrode 20U and the vibrating body 10 is increased. In addition, the distance between the electrode 20L and the vibrating body 10 is increased, and the capacitance between the electrode 20L and the vibrating body 10 is decreased.
When the capacitance changes in this way, the potential of the electrode 20U changes so that the potential difference between the electrode 20U and the vibrating body 10 decreases, and the potential of the electrode 20L increases so that the potential difference between the electrode 20L and the vibrating body 10 increases. Changes. Here, since a potential difference is generated between the electrode 20U and the electrode 20L, a current flows through the secondary coil of the transformer 110.

  Further, when the vibrating body 10 is displaced to the electrode 20L side, the distance between the electrode 20L and the vibrating body 10 is shortened, and the capacitance between the electrode 20L and the vibrating body 10 is increased. In addition, the distance between the electrode 20U and the vibrating body 10 is increased, and the capacitance between the electrode 20U and the vibrating body 10 is decreased. Then, the potential of the electrode 20L changes so that the potential difference between the electrode 20L and the vibrating body 10 becomes small, and the potential of the electrode 20U changes so that the potential difference between the electrode 20U and the vibrating body 10 becomes large. Here, a potential difference is generated between the electrode 20U and the electrode 20L, and a current flows through the secondary coil of the transformer 110 in a direction opposite to that when the vibrating body 10 is displaced in the direction of the electrode 20U.

  When a current flows through the secondary coil of the transformer 110, a current also flows through the primary coil of the transformer 110 corresponding to this current. The signal that has flowed through the primary coil is amplified by the amplification unit 130, and the amplified signal is output from the amplification unit 130 as an acoustic signal representing the sound collected by the microphone 2.

  In this modification, when the impedance of the transformer 110 is low, the frequency characteristics at a low frequency may be deteriorated due to the influence of the load capacity of the microphone 2. In this case, an amplifier having a high impedance may be connected to the electrodes 20U and 20L instead of the transformer 110 to suppress a decrease in frequency characteristics.

DESCRIPTION OF SYMBOLS 1 ... Electrostatic speaker, 2 ... Frame, 10 ... Vibrating body, 20, 20U, 20L ... Electrode, 30, 30U, 30L ... Elastic member, 60, 60U, 60L ... Protection member, 70 ... Flexible substrate, 100 ... Drive Circuit: 110: Transformer, 111: Bias power supply, 130: Amplifier, 140: First connector, 200: Acoustic signal generation circuit, 701 to 703: Conductor, 704, 705 ... Film, D1: Diode, R11 to R13 …Resistor

Claims (5)

A flexible electrode;
A vibrator having flexibility and facing the electrode at a distance;
An elastic member having elasticity and disposed between the electrode and the vibrator;
It has a 1st conductor part which has electroconductivity, and a 2nd conductor part which has electroconductivity, and the edge part of the 1st conductor part and the edge part of the 2nd conductor part are arranged side by side, and it has flexibility A flexible substrate ;
An adhesive having conductivity between the surface of the electrode and the first conductor portion;
An adhesive having conductivity between the vibrator and the second conductor portion ;
Before SL end of the second conductor portion and the end portion of the first conductor portion, the electrode, electrostatic transducer, characterized in that positioned outside the edge of the vibrating member and the elastic member.   The electrostatic transducer according to claim 1, comprising a plurality of the flexible substrates. The static transducer according to claim 2, wherein the electrostatic transducer has a shape having a plurality of sides in a plan view from the electrode side, and includes at least one flexible substrate corresponding to each side. Electric transducer. The frame according to any one of claims 1 to 3, further comprising: a frame disposed at an edge of the electrostatic transducer and having a connector into which an end of the first conductor portion and an end of the second conductor portion are fitted. The electrostatic transducer according to any one of the above. A second elastic member located on the opposite side of the elastic member from the vibrating body and having elasticity;
A second electrode having flexibility, located on the opposite side of the vibrating body as viewed from the second elastic member,
The flexible substrate includes a conductive third conductor portion, the end portion of the first conductor portion, the end portion of the second conductor portion, and the end portion of the third conductor portion are arranged side by side,
An adhesive having conductivity between the surface of the second electrode and the third conductor portion;
Said end portion of said first conductor portion disposed parallel base, the said end portion of said end portion of the second conductor section and the third conductor portion, the electrode, the second electrode, the vibration body, The electrostatic transducer according to claim 1, wherein the electrostatic transducer is located outside an edge of the elastic member and the second elastic member.

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