JP2007104371A - Electrostatic ultrasonic wave transducer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize removal of an electrode contact from a vibrating membrane at low cost and using a simple constitution, without the possibility of destroying a conductive layer(deposited film layer) at the electrode contact. <P>SOLUTION: A vibration membrane 12 with an electrode removing portion 122 is arranged and fixed by bonding on a membrane frame member 123 at first. Under the condition with the vibration membrane 12 arranged on the membrane frame member 123, a conductive rubber 127 is arranged at the electrode removing portion 122. Then, the conductive rubber 127 is fitted with pressure and is fixed to the electrode removing portion 122 by using a metallic member 124 formed by conductive material with a connected electrode wire 126. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrostatic ultrasonic transducer, and in particular, the extraction of an electrode contact from a vibrating membrane is realized with an inexpensive and simple configuration without fear of destroying the deposited film layer (conductive layer) of the electrode contact portion. The present invention relates to an electrostatic ultrasonic transducer.

  Conventionally, an electrostatic ultrasonic transducer is known as a broadband oscillation type ultrasonic transducer capable of generating a high sound pressure over a high frequency band. FIG. 5 shows a configuration example of a broadband oscillation type electrostatic ultrasonic transducer. This electrostatic ultrasonic transducer is called a pull type because it works only in the direction in which the vibrating membrane is attracted to the fixed electrode side.

  The electrostatic ultrasonic transducer shown in FIG. 5 uses a dielectric 131 (insulator) such as PET (polyethylene terephthalate resin) having a thickness of about 3 to 10 μm as a vibrating body (vibrating film). An upper electrode 132 formed as a metal foil such as aluminum is integrally formed on the upper surface of the dielectric 131 by a process such as vapor deposition, and a lower electrode 133 formed of brass is formed on the lower surface of the dielectric 131. It is provided so that it may contact a part. The lower electrode 133 is connected to a lead 152 and fixed to a base plate 135 made of bakelite or the like.

  The upper electrode 132 is connected to a lead 153, and the lead 153 is connected to the DC bias power supply 150. A DC bias voltage for attracting the upper electrode of about 50 to 150 V is constantly applied to the upper electrode 132 by the DC bias power source 150, and the upper electrode 132 is attracted to the lower electrode 133 side. Reference numeral 151 denotes a signal source.

  The dielectric 131, the upper electrode 132, and the base plate 135 are caulked by the case 130 together with the metal rings 136, 137, and 138 and the mesh 139.

  On the surface of the lower electrode 133 on the dielectric 131 side, a plurality of minute grooves (uneven portions) having a non-uniform shape of about several tens to several hundreds of μm are formed. Since this minute groove becomes a gap between the lower electrode 133 and the dielectric 131, the electrostatic capacity distribution between the upper electrode 132 and the lower electrode 133 changes minutely. These random minute grooves are formed by manually roughing the surface of the lower electrode 133 with a file. An electrostatic ultrasonic transducer has a wide frequency characteristic by forming innumerable capacitors having different gap sizes and depths (see, for example, Patent Documents 1 and 2).

  As described above, the electrostatic ultrasonic transducer shown in FIG. 5 is conventionally known as a broadband ultrasonic transducer (Pull type) capable of generating a relatively high sound pressure over a wide frequency band. .

  However, the maximum value of the sound pressure is slightly low, for example, the sound pressure is as low as 120 dB or less, and the sound pressure is slightly insufficient for use as an ultrasonic speaker. An ultrasonic sound pressure of 120 dB or more is necessary for the parametric effect to sufficiently appear in an ultrasonic speaker. However, it is difficult to achieve this numerical value with an electrostatic ultrasonic transducer (pull type). Polymer piezoelectric elements such as ceramic piezoelectric elements and PVDF have been used as ultrasonic transmitters. However, since the piezoelectric element has a sharp resonance point regardless of the material, and is practically used as an ultrasonic speaker by being driven at the resonance frequency, the frequency region where a high sound pressure can be secured is extremely narrow. That is, it can be said that it is a narrow band.

  In order to solve such a problem, an electrostatic ultrasonic transducer as shown in FIG. 6 is currently proposed (Japanese Patent Application No. 2004-173946). Such a structure is generally referred to as a push-pull type, and has the ability to satisfy both high bandwidth and high sound pressure at the same time as compared to a pull type electrostatic ultrasonic transducer. .

  In FIG. 6, the push-pull type electrostatic ultrasonic transducer includes a pair of fixed electrodes 10 and 11 including a conductive member formed of a conductive material that functions as an electrode, and a pair of fixed electrodes. It has a vibration film 12 having a (deposition film layer) 121, a pair of fixed electrodes 10 and 11, and a member (not shown) for holding the vibration film.

  The vibration film 12 includes an insulating layer 120 and a conductive layer 121 formed of a conductive material. The conductive layer 121 is unipolar (positive or negative) by a DC bias power supply 16. DC bias voltage) may be applied.

  In addition, the pair of fixed electrodes 10 and 11 have the same number and a plurality of through holes (stepped through holes) 14 at positions facing each other with the vibration film 12 therebetween, and the conductive members of the pair of fixed electrodes 10 and 11. An AC signal is applied between the signal sources 18A and 18B. Capacitors are formed on the fixed electrode 10 and the conductive layer 121, and on the fixed electrode 11 and the conductive layer 121, respectively.

  In the above configuration, in the ultrasonic transducer, a DC bias voltage having a single polarity (positive polarity in this example) is applied to the conductive layer 121 of the vibration film 12 by the DC bias power supply 16. On the other hand, an AC signal is applied to the pair of fixed electrodes 10 and 11 by the signal sources 18A and 18B. As a result, in the positive half cycle of the AC signal output from the signal sources 18A and 18B, since a positive voltage is applied to the fixed electrode 10, the surface portion 13A not sandwiched between the fixed electrodes of the vibrating membrane 12 is applied. The electrostatic repulsive force acts, and the surface portion 13A is pulled downward in FIG. At this time, since a negative voltage is applied to the opposed fixed electrode 11, an electrostatic attraction force acts on the back surface portion 13B which is the back surface side of the surface portion 13A of the vibration film 12, The back surface portion 13B is pulled further upward in FIG.

  Accordingly, the membrane portion of the vibrating membrane 12 that is not sandwiched between the pair of fixed electrodes 10 and 11 receives an electrostatic repulsive force and an electrostatic repulsive force in the same direction. Similarly, in the negative half cycle of the AC signal output from the signal sources 18A and 18B, the electrostatic attracting force is applied to the upper surface portion 13A of the vibrating membrane 12 in FIG. In FIG. 6, an electrostatic repulsive force acts on the upper side, and the film portion not sandwiched between the pair of fixed electrodes 10 and 11 of the vibrating membrane 12 receives the electrostatic repulsive force and the electrostatic repulsive force in the same direction. In this way, the direction in which the electrostatic force changes alternately while the vibrating membrane 12 receives the electrostatic repulsive force and the electrostatic repulsive force in the same direction according to the change in polarity of the AC signal. An acoustic signal having a sound pressure level sufficient to obtain a parametric array effect can be generated.

  In this way, the ultrasonic transducer is called a push-pull type because the vibrating membrane 12 receives a force from the pair of fixed electrodes 10 and 11 and vibrates. The push-pull type electrostatic ultrasonic transducer is capable of simultaneously satisfying wide bandwidth and high sound pressure compared to the pull type electrostatic ultrasonic transducer that only acts on the vibrating membrane. have.

  In the electrostatic ultrasonic transducer shown in FIG. 6, the fixed electrodes 10 and 11 may be made of a conductive material. For example, SUS, brass, iron, or nickel may be used alone. In addition, since it is necessary to reduce the weight, a desired hole processing is performed on a glass epoxy substrate or a paper phenol substrate generally used for circuit boards, and then plating is performed with nickel, gold, silver, copper, or the like. It is also possible. In this case, in order to prevent warping after molding, it is also effective to devise plating on the both surfaces. However, in consideration of insulation, it is desirable that some kind of insulation treatment be performed on the vibration film side of each fixed electrode. For example, a convex portion insulated with a liquid solder resist, a photosensitive film, a photosensitive coating material, a non-conductive paint, an electrodeposition material, or the like is formed.

  As described above, in the push-pull type electrostatic ultrasonic transducer, a high voltage DC bias voltage is applied to the vibration film, and an AC voltage is applied to the fixed electrode, so that the fixed electrode-vibration film The membrane part vibrates due to the electrostatic force (attraction and repulsive force) acting on. In this case, in order to realize the vibration of the ultrasonic band, it is necessary to reduce the hole diameter of the vibration part to several mm or less, and by providing a large number of vibration holes, a transducer with high followability and high output is configured. There is a need.

By the way, in the pull-type electrostatic ultrasonic transducer and the push-pull type electrostatic ultrasonic transducer, it is necessary to apply a DC bias voltage to the vibration film. It is not easy to take out, and a method of reducing the contact resistance by metallicon (metal spraying) generally used for a film capacitor or the like is effective. However, there is a problem that the apparatus and the like become large in the manufacturing process by metallicon (metal spraying). In addition, there is a method of taking out the electrode by the metal contact by a structure in which the metal member is pressed into contact with the vapor deposition layer portion (conductive layer). There is.
JP 2000-50387 A JP 2000-50392 A

  As described above, in order to take out the electrode contact from the vibration film in the electrostatic ultrasonic transducer, the contact resistance is reduced by metallicon (metal spraying), or the metal member is pressed against the vapor deposition layer portion (conductive layer). The method is used. However, each method has a problem, and it is not easy to take out the electrode contact from the vibrating membrane.

  The present invention has been made to solve such a problem, and an object of the present invention is to extract an electrode contact from a vibration film in an electrostatic ultrasonic transducer, and to conduct a conductive layer (deposition film layer) of the electrode contact portion. It is an object of the present invention to provide an ultrasonic transducer that can be realized with an inexpensive and simple configuration without fear of destroying the antenna.

The present invention has been made to solve the above-described problems, and an ultrasonic transducer according to the present invention includes a first fixed electrode having a plurality of holes and a plurality of pairs that are paired with the first fixed electrode. A second fixed electrode in which a hole is formed; a vibration film that is sandwiched between the pair of fixed electrodes and has a conductive layer to which a DC bias voltage is applied; and the pair of fixed electrode and the vibration film An electrostatic ultrasonic transducer in which an AC signal is applied between the pair of fixed electrodes, wherein the vibration film is placed on a film frame member, and the vibration film A pressing member formed of conductive rubber is placed on the electrode extraction portion of the conductive layer, and the pressing member is attached to the electrode extraction portion by a fixing member formed of a conductive material to which one end of the electrode wiring is connected. Characterized by being pressed and fixed To.
With such a configuration, the vibration film provided with the electrode take-out portion is arranged and fixed on the film frame member by a method such as adhesion. Then, a pressing member such as conductive rubber is disposed on the electrode extraction portion in a state where the vibration film is disposed on the film frame member. Then, the pressing member is pressed against and fixed to the electrode take-out portion by a conductive material fixing member to which the electrode wiring is connected. The pressing contact fixing of the pressing member to the electrode extraction portion is performed, for example, by sandwiching the pressing member and the electrode extraction portion and fixing the fixing member and the film frame member with screws.
This eliminates the need for a processing apparatus that applies metallicon (metal spraying) or the like to the electrode lead-out portion, thereby reducing the equipment cost of the manufacturing process. In addition, the electrode contact can be configured without destroying and deteriorating the conductive layer, and the adhesion between the electrode take-out portion and the electrode (conductive rubber) can be secured, so that the contact resistance can be lowered.

The electrostatic ultrasonic transducer according to the present invention includes a first fixed electrode having a plurality of holes formed therein, and a second fixed electrode having a plurality of holes formed in pairs with the first fixed electrodes. A vibration film sandwiched between the pair of fixed electrodes, having a conductive layer to which a DC bias voltage is applied to the conductive layer, and a holding member that holds the pair of fixed electrodes and the vibration film, An electrostatic ultrasonic transducer in which an AC signal is applied between a pair of fixed electrodes, and a groove is formed in an outer peripheral portion of the film frame material on which the vibration film is placed. An electrode extraction part is formed in which the conductive layer is exposed in a shape covering the groove part, and the vibration film is placed on the film frame member so as to cover the groove part with the electrode extraction part of the vibration film, With the electrode extraction part covering the groove part, with conductive rubber The formed pressing member is inserted into the groove portion from the upper surface of the electrode extraction portion, and the pressing member is pressed against the groove portion and fixed by a fixing member formed of a conductive material to which one end of the electrode wiring is connected. It is characterized by that.
With such a configuration, in the push-pull type electrostatic ultrasonic transducer, a groove is provided in the periphery of the membrane frame material for fixing the vibrating membrane, and the vibrating membrane is covered with the groove portion of the membrane frame material. An electrode lead-out portion is provided in a simple shape. Then, the vibrating membrane is disposed on the membrane frame material so that the electrode extraction portion of the diaphragm covers the groove portion of the membrane frame material, and the electrode extraction portion of the diaphragm is made of the membrane frame material by a pressing member made of conductive rubber. Push it into the groove. Then, the pressing member is pressed against the groove portion of the film frame member and the electrode take-out portion is pressed and fixed to the film frame member by a fixing member formed of a conductive material to which the electrode wiring is connected. The pressing contact fixing of the pressing member to the groove portion is performed, for example, by sandwiching the pressing member and the electrode extraction portion and fixing the fixing member and the film frame member with screws.
This eliminates the need for a processing apparatus that applies metallicon (metal spraying) or the like to the electrode lead-out portion, thereby reducing the equipment cost of the manufacturing process. In addition, the electrode contact can be configured without destroying and deteriorating the conductive layer, and the adhesion between the electrode take-out portion and the electrode can be secured, so that the contact resistance can be lowered. In addition, it is not necessary to bond the vibration film to the film frame material, so that the number of processes can be reduced, and the manufacturing cost can be reduced.

The electrostatic ultrasonic transducer according to the present invention includes a fixed electrode having a concavo-convex portion on a surface, a vibration film having a conductive layer and disposed on the surface of the fixed electrode, and holding the fixed electrode and the vibration film. An electrostatic ultrasonic transducer that is driven by applying an AC signal between a conductive layer of the vibrating membrane and a fixed electrode, and the vibrating membrane is placed on the membrane frame member A pressing member made of conductive rubber is placed on the electrode extraction portion of the conductive layer of the vibrating membrane, and the pressing member is formed by a fixing member formed of a conductive material to which one end of the electrode wiring is connected. The electrode take-out portion is pressed and fixed.
With such a configuration, in the pull-type electrostatic ultrasonic transducer, the vibration film provided with the electrode take-out portion is arranged and fixed on the film frame member by a method such as adhesion. Then, a pressing member such as conductive rubber is disposed on the electrode extraction portion in a state where the vibration film is disposed on the film frame member. Then, the pressing member is pressed against and fixed to the electrode take-out portion by a conductive material fixing member to which the electrode wiring is connected. The pressing contact fixing of the pressing member to the electrode extraction portion is performed, for example, by sandwiching the pressing member and the electrode extraction portion and fixing the fixing member and the film frame member with screws.
This eliminates the need for a processing apparatus that applies metallicon (metal spraying) or the like to the electrode lead-out portion, thereby reducing the equipment cost of the manufacturing process. In addition, the electrode contact can be configured without destroying and deteriorating the conductive layer, and the adhesion between the electrode take-out portion and the electrode (conductive rubber) can be secured, so that the contact resistance can be lowered.

The electrostatic ultrasonic transducer according to the present invention includes a fixed electrode having a concavo-convex portion on a surface, a vibration film having a conductive layer and disposed on the surface of the fixed electrode, and holding the fixed electrode and the vibration film. An electrostatic ultrasonic transducer that is driven by applying an AC signal between a conductive layer of the vibrating membrane and a fixed electrode, and a film frame member on which the vibrating membrane is placed A groove is formed on the outer periphery of the electrode, and the diaphragm is formed with an electrode take-out part with a conductive layer exposed in a shape covering the groove, and the groove is covered with the electrode take-out part of the diaphragm In this way, the vibration film is placed on the film frame member, and the pressing member formed of conductive rubber is inserted into the groove portion from the upper surface of the electrode extraction portion with the electrode extraction portion covering the groove portion. And one end of the electrode wiring was connected The fixing member formed of a conductive material, wherein the pressing member is pressed against the groove, and wherein the fixed.
With such a configuration, in the pull-type electrostatic ultrasonic transducer, a groove is provided in the peripheral portion of the film frame material for fixing the vibration film, and the vibration film covers the groove of the film frame material. An electrode extraction part is provided in the shape. Then, the vibrating membrane is disposed on the membrane frame material so that the electrode extraction portion of the diaphragm covers the groove portion of the membrane frame material, and the electrode extraction portion of the diaphragm is made of the membrane frame material by a pressing member made of conductive rubber. Push it into the groove. Then, the pressing member is pressed against the groove portion of the film frame member and the electrode take-out portion is pressed and fixed to the film frame member by a fixing member formed of a conductive material to which the electrode wiring is connected. The pressing contact fixing of the pressing member to the groove portion is performed, for example, by sandwiching the pressing member and the electrode extraction portion and fixing the fixing member and the film frame member with screws.
This eliminates the need for a processing apparatus that applies metallicon (metal spraying) or the like to the electrode lead-out portion, thereby reducing the equipment cost of the manufacturing process. In addition, the electrode contact can be configured without destroying and deteriorating the conductive layer, and the adhesion between the electrode take-out portion and the electrode can be secured, so that the contact resistance can be lowered. In addition, it is not necessary to bond the vibration film to the film frame material, so that the number of processes can be reduced, and the manufacturing cost can be reduced.

[Description of Electrostatic Ultrasonic Transducer Subject of the Present Invention]
The present invention is characterized in a method of forming an electrode for giving a signal to a vibrating membrane in an electrostatic ultrasonic transducer. The electrostatic ultrasonic transducer that is the subject of the present invention includes a push-pull type electrostatic ultrasonic transducer and a pull type electrostatic ultrasonic transducer.

  FIG. 1A is a diagram illustrating a configuration example of a push-pull electrostatic ultrasonic transducer that is an object of the present invention. In this electrostatic ultrasonic transducer, the vibrating membrane 12 is sandwiched between a pair of fixed electrodes 10, 11, a DC bias voltage is applied to the conductive layer 121 of the vibrating membrane 12 by a DC bias power supply 16, and the pair of fixed electrodes 10. , 11 is configured to apply an AC signal from the signal sources 18A, 18B. The basic configuration and operation are the same as those of the push-pull type electrostatic ultrasonic transducer shown in FIG.

  FIG. 1B is a diagram illustrating a configuration example of a pull-type electrostatic ultrasonic transducer that is an object of the present invention. In this electrostatic ultrasonic transducer, the vibrating membrane 12 is disposed on the fixed electrode 11A having the concavo-convex portions 15A and 15B, and a DC bias voltage is applied to the conductive layer 121 of the vibrating membrane 12 by the DC bias power supply 16 to fix the vibrating membrane 12. The electrode 11A is configured to apply an AC signal from a signal source 18B. The basic configuration and operation are the same as those of the pull-type electrostatic ultrasonic transducer shown in FIG. 5 described above.

  FIG. 1C is a partially enlarged view of the vibrating membrane 12 and is a view showing an electrode extraction portion of the conductive layer of the vibrating membrane. As shown in FIG. 1C, the vibration film 12 is configured such that a conductive layer (deposition film layer) 121 is sandwiched between insulating layers 120, and only an electrode extraction portion (electrode contact portion) 122 is insulated on one side. The layer 120 is not formed. A direct current bias voltage is applied to the vibrating membrane 12 through the electrode extraction portion 122.

[Description of First Configuration Example of Electrode Portion of Vibration Membrane]
FIG. 2 is a diagram showing a first configuration example of the electrode portion of the vibrating membrane in the electrostatic ultrasonic transducer of the present invention. FIG. 2A shows the assembly procedure of the diaphragm, and FIG. 2B shows the assembled state.

As shown in FIG. 2A, in order to assemble the diaphragm 12, a film frame member 123 for adhering and fixing the diaphragm 12, a conductive rubber 127 having a high conductivity, and a conductive rubber 127 are connected to the electrode extraction portion. A metal member 124 is prepared for pressure contact with 122. The metal member 124 is configured to draw out the electrode wiring 126 by soldering or the like. Further, as the performance of the conductive rubber 127, a high conductivity type having a volume resistivity of about 1 × 10 ⁻¹ Ωcm is desirable. In the example shown in FIG. 2, the vibrating membrane 12 and the membrane frame member 123 have a disc shape, but the vibrating membrane 12 and the membrane frame member 123 may have arbitrary shapes.

And the assembly of this diaphragm 12 is performed by the following procedure.
First, the peripheral part of the vibration film 12 is bonded to the outer peripheral part of the film frame member 123 with an adhesive (step S1). Next, the conductive rubber 127 matched with the shape of the electrode extraction part 122 is pressed against the film surface of the electrode extraction part 122 (step S2), and the metal member 124 is pressed from above with the metal member 124. Further, the electrode wiring 126 is drawn out from the metal member 124 by soldering or the like (step S3).

  When the vibrating membrane is assembled, as shown in FIG. 2B, the periphery of the vibrating membrane 12 is bonded and fixed on the membrane frame member 123, and the conductive film is placed on the electrode extraction portion 122 of the vibrating membrane 12. The conductive rubber 127 is disposed, and the conductive rubber 127 is pressed and fixed to the electrode extraction portion 122 by the metal member 124. In FIG. 2B, the screw hole 125 and the screw are omitted for easy viewing of the drawing.

  With the configuration described above, there is no need for a processing apparatus that applies metallicon (metal spray) or the like to the electrode extraction portion 122 of the vibration film 12, and the equipment cost of the manufacturing process can be reduced. In addition, an electrode contact can be formed without destroying and deteriorating the conductive layer of the electrode lead-out part 122, and the adhesion between the electrode lead-out part 122 and the electrodes (the conductive rubber 127 and the metal member 124) can be secured. The resistance can be lowered.

  Note that the configuration example of the electrode portion of the vibration membrane shown in FIG. 2 includes the vibration membrane of the push-pull type electrostatic ultrasonic transducer shown in FIG. 1A and the pull-type static electricity shown in FIG. The present invention can be applied to both vibration membranes of electric ultrasonic transducers.

[Description of Second Configuration Example of Electrode Portion of Vibration Membrane]
FIG. 3 is a diagram showing a second configuration example of the electrode portion of the vibrating membrane in the electrostatic ultrasonic transducer of the present invention. FIG. 3A shows the procedure for assembling the diaphragm, and FIG. 3B shows the assembled state.

  In the second configuration example, as shown in FIG. 3A, an electrode extraction portion 122A is provided over the entire outer periphery of the vibrating membrane 12A, and a DC bias voltage is applied to the vibrating membrane 12A through the electrode extraction portion 122A. To do.

  In order to assemble the vibrating membrane 12A, the membrane frame member 123A for fixing the vibrating membrane 12A, the conductive rubber 127A having a ring-shaped high conductivity, and the conductive rubber 127A are pressed against the electrode extraction portion 122A. A metal member 124A for attachment is prepared. The metal member 124A is configured to draw out the electrode wiring 126 by soldering or the like.

  The film frame member 123A is provided with a groove 128 in an annular shape. As shown in FIGS. 4A and 4B, an electrode extraction portion 122A of the vibrating membrane 12A is disposed on the groove 128, and the electrode extraction portion 122A is placed in the groove 128 by the conductive rubber 127A. Press to secure.

The performance of the conductive rubber 127A is preferably a high conductivity type having a volume specific resistance of about 1 × 10 ⁻¹ Ωcm. In the example shown in FIG. 3, the vibrating membrane 12A and the membrane frame member 123A are shown in a disc shape, but the vibrating membrane 12A and the membrane frame member 123A may have any shape.

The assembly of the vibrating membrane 12A is performed according to the following procedure.
Referring to FIG. 3A, first, the vibrating membrane 12A is placed on the membrane frame member 123A so that the electrode extraction portion 122A of the vibrating membrane 12A covers the groove 128 of the membrane frame member 123A. (Step S11), the conductive rubber 127A is pushed into the groove 128 from above (Step S12), and the electrode extraction portion 122A of the vibrating membrane 12A is fixed to the membrane frame member 123A. Then, the metal member 124A is disposed on the upper part of the conductive rubber 127A, and the metal member 124A and the membrane frame member 123A are fixed by screws, so that the conductive rubber 127A and the electrode extraction portion 122A are pressed against the groove 128 by screwing. To do. Further, the electrode wiring 126A is drawn out from the metal member 124A by soldering or the like (step S13).

  When the vibrating membrane is assembled, as shown in FIG. 3B, the vibrating membrane 12A is fixed on the membrane frame member 123A by the conductive rubber 127A, and the conductive rubber 127A is pressure-fixed by the metal member 124. It will be in the state. Note that in FIG. 3B, the screw hole 125A and the screw are omitted for easy viewing of the drawing.

  With the configuration described above, there is no need for a processing apparatus that applies metallicon (metal spraying) or the like to the electrode lead-out portion 122A, and equipment costs in the manufacturing process can be reduced. In addition, an electrode contact can be formed without destroying and deteriorating the conductive layer (deposited film layer) of the electrode lead-out portion 122A, and the adhesion between the electrode lead-out portion 122A and the electrodes (the conductive rubber 127A and the metal member 124A) is secured. Therefore, the contact resistance can be lowered. In addition, it is not necessary to bond the vibrating membrane 12A to the membrane frame member 123A, so that the corresponding steps can be reduced and the manufacturing cost can be reduced.

  Note that the configuration example of the electrode portion of the vibration membrane shown in FIG. 3 includes the vibration membrane of the push-pull type electrostatic ultrasonic transducer shown in FIG. 1A and the pull-type static electricity shown in FIG. The present invention can be applied to both vibration membranes of electric ultrasonic transducers.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the electrostatic ultrasonic transducer of the present invention and the above-described illustrated examples, and various modifications are made without departing from the scope of the present invention. Of course you get.

The figure which shows the structural example of the electrostatic ultrasonic transducer used as the object of this invention. The figure which shows the 1st structural example of the electrode part of a diaphragm. The figure which shows the 2nd structural example of the electrode part of a diaphragm. The figure for demonstrating the insertion method of a conductive rubber and a groove part. The figure which shows the structural example of a pull type electrostatic ultrasonic transducer. The figure which shows the structural example of a push-pull type electrostatic ultrasonic transducer.

Explanation of symbols

10, 11 Fixed electrode, 12, 12A Vibration membrane, 13A Surface portion, 13B Back surface portion 14 Through hole (stepped through hole), 15A convex portion, 15B concave portion, 16 DC bias power supply,
18A, 18B signal source, 120 insulating layer, 121 conductive layer (deposited film layer),
122, 122A electrode extraction part, 123, 123A film frame material,
124, 124A metal member, 125, 125A screw hole,
126, 126A Electrode wiring, 127, 127A Conductive rubber

Claims (4)

A first fixed electrode formed with a plurality of holes, a second fixed electrode formed with a plurality of holes paired with the first fixed electrode, and a conductive layer sandwiched between the pair of fixed electrodes. And a vibration film to which a DC bias voltage is applied to the conductive layer, the pair of fixed electrodes, and a holding member for holding the vibration film, and an AC signal is applied between the pair of fixed electrodes. An electrostatic ultrasonic transducer,
The vibrating membrane is placed on a membrane frame member,
A pressing member formed of conductive rubber is placed on the electrode extraction portion in the conductive layer of the vibration membrane,
An electrostatic ultrasonic transducer, wherein the pressing member is pressed against and fixed to the electrode take-out portion by a fixing member formed of a conductive material to which one end of an electrode wiring is connected. A first fixed electrode formed with a plurality of holes, a second fixed electrode formed with a plurality of holes paired with the first fixed electrode, and a conductive layer sandwiched between the pair of fixed electrodes. And a vibration film to which a DC bias voltage is applied to the conductive layer, the pair of fixed electrodes, and a holding member for holding the vibration film, and an AC signal is applied between the pair of fixed electrodes. An electrostatic ultrasonic transducer,
Grooves are formed on the outer periphery of the film frame material on which the vibration film is placed,
The vibration film is formed with an electrode extraction part in which the conductive layer is exposed in a shape covering the groove part,
The vibrating membrane is placed on the membrane frame material so as to cover the groove portion with the electrode extraction portion of the vibrating membrane,
With the electrode extraction part covering the groove part, a pressing member formed of conductive rubber is inserted into the groove part from the upper surface of the electrode extraction part,
An electrostatic ultrasonic transducer characterized in that the pressing member is pressed against and fixed to the groove portion by a fixing member formed of a conductive material to which one end of an electrode wiring is connected. A fixed electrode having a concavo-convex portion on a surface; a vibration film having a conductive layer and disposed on a surface of the fixed electrode; and a member for holding the fixed electrode and the vibration film, the conductive layer of the vibration film An electrostatic ultrasonic transducer that is driven by applying an AC signal between a fixed electrode and a fixed electrode,
The vibrating membrane is placed on a membrane frame member,
A pressing member formed of conductive rubber is placed on the electrode extraction portion in the conductive layer of the vibration membrane,
An electrostatic ultrasonic transducer, wherein the pressing member is pressed against and fixed to the electrode take-out portion by a fixing member formed of a conductive material to which one end of an electrode wiring is connected. A fixed electrode having a concavo-convex portion on a surface; a vibration film having a conductive layer and disposed on a surface of the fixed electrode; and a member for holding the fixed electrode and the vibration film, the conductive layer of the vibration film An electrostatic ultrasonic transducer that is driven by applying an AC signal between a fixed electrode and a fixed electrode,
Grooves are formed on the outer periphery of the film frame material on which the vibration film is placed,
The vibration film is formed with an electrode extraction part in which the conductive layer is exposed in a shape covering the groove part,
The vibrating membrane is placed on the membrane frame material so as to cover the groove portion with the electrode extraction portion of the vibrating membrane,
With the electrode extraction part covering the groove part, a pressing member formed of conductive rubber is inserted into the groove part from the upper surface of the electrode extraction part,
An electrostatic ultrasonic transducer characterized in that the pressing member is pressed against and fixed to the groove portion by a fixing member formed of a conductive material to which one end of an electrode wiring is connected.

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