JP2010187305A - Acoustic diaphragm and method for manufacturing the same, and electroacoustic transducer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an acoustic diaphragm that can be designed and manufactured at low cost and can effectively restrain divisional vibrations of subdomes, to provide a method of manufacturing the acoustic diaphragm, and to obtain an electroacoustic transducer using the acoustic diaphragm. <P>SOLUTION: The acoustic diaphragm includes a diaphragm ground 30, including a main dome 31 and the subdome 32 surrounding the periphery of the main dome 31; and a reinforcing member 10, made of a hot melt adhesive provided in the subdome 32. The electroacoustic transducer 1 includes a magnetic circuit component; a voice coil disposed in a magnetic gap formed by the magnetic circuit component; and the acoustic diaphragm 3, to which the voice coil has been fixed. The acoustic diaphragm 3 is an acoustic diaphragm described above. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an acoustic diaphragm that can be designed and manufactured at low cost and can effectively suppress the divided vibration of a sub-dome, a manufacturing method thereof, and an electroacoustic transducer using the acoustic diaphragm.

  The electroacoustic transducer converts the electrical signal input from the outside into the vibration of the acoustic diaphragm, such as a speaker unit or a headphone unit having a similar structure to the speaker unit, and outputs the sound wave, and a microphone. It can be roughly classified into a unit such as a unit that receives sound waves input from the outside with an acoustic diaphragm, converts them into electrical signals, and outputs them.

  In addition, among the speaker unit, the headphone unit, and the microphone unit, the acoustic diaphragm configured by the main dome and the ring-shaped sub dome, and the voice coil fixed to the acoustic diaphragm, the electrical signal is converted into a sound wave. Or the type which converts a sound wave into an electric signal is called a dynamic speaker unit, a dynamic headphone unit, and a dynamic microphone unit, respectively.

  As a conventional example of the electroacoustic transducer described above, the configuration of a dynamic headphone unit will be described with reference to FIG.

  The dynamic headphone unit 1 has a unit frame 2 as a base, and additionally includes a magnetic circuit component, an acoustic diaphragm 3 and a voice coil 4 as main components.

  The unit frame 2 is a disk-shaped component, and has a cylindrical portion 21 at the center, and the inner peripheral side of the cylindrical portion 21 is a through hole.

  The magnetic circuit constituting member includes a yoke 5 formed in a circular dish shape, a disk-shaped magnet 6 fixed to the inner bottom surface of the yoke 5, and a front end (upper end in FIG. 12) surface of the magnet 6. A disk-shaped pole piece 7 is provided. A cylindrical gap 8 is formed over the entire circumference between the inner peripheral surface of the front end portion of the yoke 5 and the pole piece 7, and this gap 8 becomes a magnetic gap through which the magnetic flux from the magnet 6 passes. Yes. The outer periphery of the yoke 5 is fitted into the cylindrical portion 21 of the unit frame 2 and integrated with the unit frame 2.

  The acoustic diaphragm 3 has a main dome 31 at the center and a sub dome 32 surrounding the main dome 31, and the outer peripheral edge of the sub dome 32 is fixed to the outer peripheral edge of the unit frame 2. The acoustic diaphragm 3 is a thin plate-like component made of, for example, a thermoplastic resin. The acoustic diaphragm 3 is acoustically vibrated by an electromagnetic force generated in a voice coil 4 described later with an outer peripheral edge fixed to the unit frame 2 as a fulcrum. It can vibrate in the front-rear direction against the elasticity of the plate 3 itself. The front end of the voice coil 4 is fixed to the back side of the acoustic diaphragm 3 along the boundary between the main dome 31 and the sub dome 32.

  The voice coil 4 is a part formed by winding a thin conducting wire in a cylindrical shape, and is arranged in the magnetic gap, and can move in the front-rear direction without touching the yoke 5 and the pole piece 7 together with the acoustic diaphragm 3. It has become.

  As apparent from the configuration described above, since the voice coil 4 is disposed in the magnetic gap, when an audio signal is input to the voice coil 4, the current according to the audio signal and the magnetic flux in the magnetic gap are reduced. Due to the electromagnetic force, the voice coil 4 moves in the front-rear direction. Since the acoustic diaphragm 3 vibrates back and forth together with the voice coil 4, a sound wave according to the audio signal is emitted from the acoustic diaphragm 3.

  The main dome 31 of the acoustic diaphragm 3 needs to have an appropriate rigidity or stiffness so as not to be deformed by vibration, and the sub dome 32 needs to have elasticity so that the voice coil 4 performs a piston motion. However, split vibration is generated due to the elasticity of the sub dome 32, and abnormal noise may occur due to abnormal vibration different from the signal input to the peripheral portion of the acoustic diaphragm 3.

As one of the countermeasures against this problem, there is an invention described in Patent Document 1. The acoustic diaphragm 3 shown in FIGS. 13 to 15 is an acoustic diaphragm having substantially the same configuration as the acoustic diaphragm according to the invention described in Patent Document 1. In addition, the same code | symbol was attached | subjected about the same component as the conventional acoustic diaphragm shown in FIG.
In the sub-dome 32 of the acoustic diaphragm 3 shown in FIGS. 13 to 15, V-shaped grooves 33 are formed radially along the tangential direction of the outer peripheral edge of the main dome 31 and spirally as a whole. Hereinafter, such a groove is referred to as a tangential groove 33.
The tangential groove 33 functions as a rib for reinforcement of the sub dome 32, improves the stiffness of the sub dome 32, prevents divided vibration of the sub dome 32, and the voice coil fixed to the acoustic diaphragm 3 faithfully follows the input signal. Piston motion is made.

JP 2005-303775 A

  By the way, when designing an acoustic diaphragm using the conventional tangential groove described above, in order to determine the optimum shape of the tangential groove, a prototype of an acoustic diaphragm having a different tangential groove shape is actually used. Many of them are created, and the best ones are applied to products. In order to create a large number of prototypes in this way, it is necessary to create a large number of prototype molds, which is uneconomical.

  The present invention has been made in view of the above problems, and can be designed and manufactured at low cost, and an acoustic diaphragm capable of effectively suppressing the divided vibration of the subdome, its manufacturing method, and An object of the present invention is to provide an electroacoustic transducer using the.

  The main aspect of the present invention is an acoustic diaphragm including a diaphragm body having a main dome and a sub dome surrounding the main dome, and a reinforcing member made of a hot melt adhesive provided on the sub dome. Features.

  Although it does not specifically limit in this invention, It is preferable to further provide the 2nd reinforcement member which consists of a hot-melt-adhesive provided in the said main dome.

  Moreover, although it does not specifically limit in this invention, It is preferable that the said hot-melt-adhesive is soluble in an organic solvent.

  Although not particularly limited in the present invention, it is preferable that the reinforcing member and the second reinforcing member are provided on one surface side of the diaphragm base.

  Although not particularly limited in the present invention, it is preferable that the reinforcing member and the second reinforcing member are provided integrally.

  The present invention is also a method of manufacturing an acoustic diaphragm comprising: a diaphragm base having a main dome and a sub dome surrounding the main dome; and a reinforcing member made of a hot melt adhesive provided on the sub dome. A printing process for printing a reinforcing member pattern with the hot melt adhesive at a position corresponding to the sub dome of the material thin film, and molding the material thin film on which the reinforcing member pattern is printed, and the main dome and the sub dome are provided. And a forming step of forming the diaphragm base and the reinforcing member.

  Although it does not specifically limit in this invention, It is preferable to further provide the hardening process which hardens the said hot-melt-adhesive printed as the said reinforcement member pattern.

  In the present invention, although not particularly limited, in the printing step, it is preferable that the second reinforcing member pattern is printed with the hot melt adhesive at a position corresponding to the main dome of the material thin film.

  Further, although not particularly limited in the present invention, it is preferable that the reinforcing member pattern and the second reinforcing member pattern are printed on one surface side of the material thin film.

  Further, although not particularly limited in the present invention, it is preferable that the reinforcing member pattern and the second reinforcing member pattern are integrally printed.

  Although not particularly limited in the present invention, the hot melt adhesive is soluble in an organic solvent, and the hot melt adhesive dissolved in the organic solvent in the printing step is printed on the material thin film. The curing step is preferably performed by evaporating the organic solvent of the hot melt adhesive printed on the material thin film.

  The present invention also provides an electroacoustic transducer comprising a magnetic circuit component, a voice coil disposed in a magnetic gap formed by the magnetic circuit component, and an acoustic diaphragm to which the voice coil is fixed. The acoustic diaphragm is the above-described acoustic diaphragm.

  Although not particularly limited in the present invention, the voice coil is preferably fixed to the acoustic diaphragm with a hot melt adhesive.

  According to the present invention, an acoustic diaphragm that can be designed and manufactured at low cost and can effectively suppress the divided vibration of the subdome, a manufacturing method thereof, and an electroacoustic transducer using the acoustic diaphragm are provided. be able to.

It is a top view which shows the acoustic diaphragm which concerns on embodiment of this invention. It is sectional drawing which follows the centerline of the said acoustic diaphragm. It is sectional drawing which follows the AA line of FIG. It is a top view which shows the 1st modification of the acoustic diaphragm which concerns on embodiment of this invention. It is a top view which shows the 2nd modification of the acoustic diaphragm which concerns on embodiment of this invention. It is a top view which shows the 3rd modification of the acoustic diaphragm which concerns on embodiment of this invention. It is a top view which shows the 4th modification of the acoustic diaphragm which concerns on embodiment of this invention. It is a top view which shows the printing process of the manufacturing method of the acoustic diaphragm which concerns on embodiment of this invention. It is sectional drawing which shows the formation process of the manufacturing method of the acoustic diaphragm which concerns on embodiment of this invention. It is sectional drawing of the acoustic diaphragm manufactured by the manufacturing method of the acoustic diaphragm which concerns on embodiment of this invention. It is a longitudinal cross-sectional view which shows the example of the dynamic headphone unit which is an example of the electroacoustic transducer using the acoustic diaphragm which concerns on this invention. It is a longitudinal cross-sectional view which shows the dynamic headphone unit which is an example of the conventional electroacoustic transducer. It is a top view which shows the acoustic diaphragm used for the conventional electroacoustic transducer. It is a longitudinal cross-sectional view which follows the centerline of the said acoustic diaphragm. It is sectional drawing which follows the AA line of FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of an acoustic diaphragm, an acoustic diaphragm manufacturing method, and an electroacoustic transducer according to the present invention will be described with reference to the drawings. In addition, the same code | symbol was attached | subjected about the same component as the conventional acoustic diaphragm and electroacoustic transducer mentioned above.

[Acoustic diaphragm]
<First Embodiment>
In the acoustic diaphragm 3 according to this embodiment shown in FIGS. 1 to 3, a main dome 31 and a sub dome 32 surrounding the periphery of the main dome 31 are formed at the center of the diaphragm base 30. The outer peripheral edge of the sub dome 32 is fixed to the outer peripheral edge of the unit frame 2 when attached to the unit frame 2 shown in FIG. The same material as that of a conventional acoustic diaphragm is used for the diaphragm base 30.

  A reinforcing member 10 is provided on the back side of the diaphragm base 30. The reinforcing member 10 has a main dome reinforcing member 101 provided so as to cover the entire back side of the main dome 31, a radial shape along the tangential direction of the outer peripheral edge of the main dome 31, and a spiral shape as a whole. A sub dome reinforcing member 102 provided on the back surface side of the sub dome 32 and an outer peripheral edge reinforcing member 103 provided so as to cover the back surface side of the outer peripheral edge portion of the sub dome 32 are integrally provided.

  The reinforcing member 10 is formed of a cured hot melt adhesive. This hot-melt adhesive is a polyester-based hot-melt adhesive that is soluble in an organic solvent. The hot melt adhesive applied to the material thin film that is the material of the diaphragm base during the production of the acoustic diaphragm is in the form of a paste dissolved in an organic solvent, and is cured by evaporating the organic solvent after application, Fixed to the diaphragm base. Further, even after the organic solvent evaporates and hardens, the hot melt adhesive has a property of being melted by being heated to a melting point or higher and being cured again by being cooled to a temperature lower than the melting point. Furthermore, the hot melt adhesive has a property that it is soluble in an organic solvent even after curing. In this embodiment, a hot melt adhesive having a melting point of about 150 ° C. is used.

  In the design and manufacture of the acoustic diaphragm 3 according to this embodiment described above, a large number of prototypes can be created simply by changing the plate of the reinforcing member pattern and changing the printing shape. Therefore, unlike the conventional diaphragm, there is no need to create a new mold every time the prototype is created, which is economical. Thus, the acoustic diaphragm according to the present embodiment can be designed and manufactured at a low cost.

  Moreover, since the main dome 31 is reinforced by providing the main dome reinforcing member 101 so as to cover the entire main dome 31, deformation of the main dome 31 due to sound waves can be effectively prevented.

  Further, the sub dome 32 is provided with the sub dome reinforcing member 102 radially along the tangential direction of the outer peripheral edge of the main dome 31 and spirally as a whole, so that the sub dome 32 ensures its elasticity. However, since it is partially reinforced and the stiffness is improved, it is possible to effectively prevent the occurrence of divided vibration.

  In the reinforcing member 10 of the acoustic diaphragm 3 according to the present embodiment, the main dome reinforcing member 101, the sub dome reinforcing member 102, and the outer peripheral edge reinforcing member 103 are integrally formed on the back side of the acoustic diaphragm. Although the hot melt adhesive is used, the present invention is not limited to this, and various forms can be adopted.

  For example, the main dome reinforcing member, the sub dome reinforcing member, and the outer peripheral edge reinforcing member may be provided separately on the back side of the diaphragm.

  In addition, the main dome reinforcing member, the sub dome reinforcing member, and the outer peripheral edge reinforcing member may be provided separately, and may be provided so as to be separated on the back side and the front side of the diaphragm.

  In addition, as the reinforcing member, only the sub dome reinforcing member or only the sub dome reinforcing member and the outer peripheral edge reinforcing member may be provided as a single body or separate members.

  Further, the main dome reinforcing member, the sub dome reinforcing member, and the outer peripheral edge reinforcing member may be made of different materials without using the same hot melt adhesive.

  Furthermore, in the reinforcing member 10 of the acoustic diaphragm 3 according to the present embodiment, the sub dome reinforcing member 102 is arranged radially along the tangential direction of the outer peripheral edge of the main dome 31 and spirally as a whole. However, the present invention is not limited to this, and the sub-dome reinforcing member 102 can have various shapes.

  Hereinafter, modifications of the acoustic diaphragm according to the present embodiment will be described. However, the shape of the reinforcing member of the acoustic diaphragm according to the present invention is not limited to the above embodiment and the following modified examples, and any shape that can effectively prevent the occurrence of divided vibration in the sub-dome is preferably used. be able to.

<First Modification>
In FIG. 4, the acoustic diaphragm 3 which concerns on the 1st modification of this embodiment is shown. In addition, the same code | symbol is attached | subjected about the same component as the acoustic diaphragm shown in FIG.

  The acoustic diaphragm 3 according to the first modified example has a sub dome reinforcing member 102 provided radially on the back side of the sub dome 32 from the outer peripheral edge of the main dome 31 along the radial direction of the main dome 31. This is the same as the acoustic diaphragm 3 shown in FIG.

  Since the main dome 31 is also reinforced by the acoustic diaphragm 3 shown in the first modification, deformation of the main dome 31 due to sound waves can be effectively prevented, and the sub dome 32 ensures its elasticity. However, since it is partially reinforced and the stiffness is improved, it is possible to effectively prevent the occurrence of divided vibration.

<Second Modification>
In FIG. 5, the acoustic diaphragm 3 which concerns on the 2nd modification of this embodiment is shown. In addition, the same code | symbol is attached | subjected about the same component as the acoustic diaphragm shown in FIG.

  The acoustic diaphragm 3 according to the second modified example is that the sub dome reinforcing member 102 is provided on the back side of the sub dome 32 so as to be spirally connected to the main dome reinforcing member 101 around the main dome 31. These are the same as the acoustic diaphragm 3 shown in FIGS.

  Since the main dome 31 is also reinforced by the acoustic diaphragm 3 shown in the second modified example, deformation of the main dome 31 due to sound waves can be effectively prevented, and the sub dome 32 ensures its elasticity. However, since it is partially reinforced and the stiffness is improved, it is possible to effectively prevent the occurrence of divided vibration.

<Third Modification>
In FIG. 6, the acoustic diaphragm 3 which concerns on the 3rd modification of this embodiment is shown. In addition, the same code | symbol is attached | subjected about the same component as the acoustic diaphragm shown in FIG.

  The acoustic diaphragm 3 according to the third modification is similar to that shown in FIGS. 1 to 3 except that the sub dome reinforcing member 102 is provided in an elliptical shape along the radial direction of the main dome 31 at a plurality of locations on the back side of the sub dome 32. This is the same as the acoustic diaphragm shown in FIG.

  Since the main dome 31 is also reinforced by the acoustic diaphragm 3 shown in the third modified example, deformation of the main dome 31 due to sound waves can be effectively prevented, and the sub dome 32 ensures its elasticity. However, since it is partially reinforced and the stiffness is improved, it is possible to effectively prevent the occurrence of divided vibration.

<Fourth Modification>
In FIG. 7, the acoustic diaphragm 3 which concerns on the 4th modification of this embodiment is shown. In addition, the same code | symbol is attached | subjected about the same component as the acoustic diaphragm shown in FIG.

  In the acoustic diaphragm 3 according to the fourth modification, the sub dome reinforcing member 102 is provided on the back side of the sub dome 32. The sub dome reinforcing member 102 is connected to the outer peripheral edge of the main dome 31 and extends along the radial direction of the main dome 31, and the elliptical part 106 provided at the tip of the linear part and connected to the outer peripheral edge reinforcing member 103. And have. Other than the structure of the sub dome reinforcing member 102, the acoustic diaphragm shown in FIGS.

  Since the main dome 31 is also reinforced by the acoustic diaphragm 3 shown in the fourth modified example, deformation of the main dome 31 due to sound waves can be effectively prevented, and the sub dome 32 ensures its elasticity. However, since it is partially reinforced and the stiffness is improved, it is possible to effectively prevent the occurrence of divided vibration.

[Method of manufacturing acoustic diaphragm]
An embodiment of a method for manufacturing an acoustic diaphragm according to the present invention will be described below.

<Printing process>
First, as shown in FIG. 8, a reinforcing member pattern 104 is printed on a material thin film 34 made of a square thermoplastic resin film using a hot melt adhesive dissolved in an organic solvent to form a paste. In the present embodiment, the reinforcing member pattern 104 is provided on the back surface side of the portion corresponding to the main dome reinforcing member provided on the back surface side of the portion corresponding to the main dome of the material thin film 34 and the portion corresponding to the sub dome. The portion corresponding to the sub dome reinforcing member and the portion corresponding to the outer peripheral edge reinforcing member provided so as to cover the back side of the outer peripheral edge portion of the portion corresponding to the sub dome are integrally printed. It has become. The portion corresponding to the sub dome reinforcing member is provided radially along the tangential direction of the outer peripheral edge of the portion corresponding to the main dome reinforcing member and spirally as a whole.

  In the present invention, the shape of the diaphragm pattern 104 is not limited to this. If the finally formed sub-dome reinforcing member 102 can effectively prevent the divided vibration of the sub-dome 32, the diaphragm according to the present invention described above. Various shapes can be used as illustrated in Modifications 1 to 4 of the acoustic diaphragm.

<Curing process>
Next, the hot-melt adhesive of the reinforcing member pattern 104 is cured by evaporating the organic solvent contained in the reinforcing member pattern 104 printed on the material thin film 34. Volatilization of the organic solvent can be performed by leaving it to stand at room temperature for a predetermined time, or by heating it for a predetermined time at a temperature lower than the melting point of the hot melt adhesive, or by leaving it in a low pressure or vacuum state for a predetermined time. it can.

<Molding process>
Next, as shown in FIG. 9, the material thin film 34 in which the reinforcing member pattern 104 is cured is molded using the mold 15, so that the shapes of the main dome 31 and the sub dome 32 of the acoustic diaphragm 3, and The shape of the reinforcing member 10 is formed.

  As shown in FIG. 9, the mold 15 used for forming the material thin film 34 is divided into two upper and lower molds. The upper mold 151 is provided with a sealing material 152 that seals the inside of the mold when the upper and lower molds are combined, and a blower port 153 that sends hot air into the mold. The lower mold 155 is formed with a molding portion 156 formed with a three-dimensional shape for molding the main dome and the sub dome of the acoustic diaphragm, and an intake port (not shown).

  In the present embodiment, the mold having the above-described shape is used. However, the present invention is not limited to this, and any shape can be used as long as the acoustic diaphragm according to the present invention can be molded. .

  In the formation of the acoustic diaphragm, in order to prevent the hot melt adhesive of the reinforcing member pattern 104 melted by heating from adhering to the mold 15, the material thin film 34 faces the reinforcing member pattern 104 upward and the lower mold. 155. When the mold 15 is closed, a predetermined interval is formed between the material thin film 4 and the reinforcing member pattern 104 in the mold 15 and the upper mold 151.

  After the material thin film 4 is placed on the lower mold 155, the upper mold 151 is brought into close contact with the lower mold 155, the mold 15 is sealed, and the mold 15 is overheated. The reinforcing member pattern 104 and the material thin film 34 are softened by the heat of the mold 15, and air is sucked into the mold from the air inlet provided in the lower mold 155 and the blower opening of the upper mold. Close contact with the lower mold by hot air. Then, the same shape as the forming portion 156, that is, the shape corresponding to the main dome 31 and the sub dome 32, and the shape of the reinforcing member 10 are formed.

  After the shape corresponding to the main dome 31, the sub dome 32, and the reinforcing member 10 is formed on the material thin film 34, the mold 15 is cooled, so that the material thin film 34 and the reinforcing member pattern 104 after molding are cooled and cured. To do. This cooling is performed by keeping the mold 15 at a temperature lower than the melting point of the material thin film 34 and the hot melt adhesive of the reinforcing member pattern 104 for a predetermined time.

<Resection process>
After cooling, the material thin film 34 that has been molded is taken out of the mold 15. Then, an unnecessary part is cut out from the material thin film 34, and the manufacture of the acoustic diaphragm 3 shown in FIG. 10 is completed. 9, 10, and 11, the cross-sectional shape of the reinforcing member pattern 104 is expressed in a simplified manner.

  According to the manufacturing method of the acoustic diaphragm 3 described above, even when a large number of prototypes of the acoustic diaphragm 3 are created in order to determine the optimal shape of the reinforcing member 10, the plate of the reinforcing member pattern 104 is changed and the printed shape is changed. The mold 15 can be used in common. Therefore, unlike the conventional method for manufacturing an acoustic diaphragm, there is no need to create a new mold for each trial production, which is economical. Thus, according to the method for manufacturing an acoustic diaphragm according to the present embodiment, the diaphragm can be designed and manufactured at low cost.

  In the present embodiment, the hot-melt adhesive soluble in the organic solvent is used for printing the reinforcing member pattern 104 in the organic solvent. However, the present invention is not limited to this, and various forms are used. Can be adopted.

  For example, a hot melt adhesive that is insoluble in an organic solvent may be used for printing the reinforcing member pattern, and this may be heated and melted with a glue gun or the like.

[Electroacoustic transducer]
Next, an example of the electroacoustic transducer according to the present invention will be described using the dynamic headphone unit 1 shown in FIG. 11 as an example. Since the configuration of the electroacoustic transducer shown in FIG. 11 is the same as the configuration of the conventional electroacoustic transducer shown in FIG. 12 except for the structure of the acoustic diaphragm 3, detailed description thereof is omitted. In the dynamic headphone unit shown in FIG. 11, the same components as those of the dynamic headphone unit shown in FIG.

  As shown in FIG. 11, the dynamic headphone unit 1 according to the present embodiment has a reinforcing member 10 formed on the back side of the acoustic diaphragm 3. The configuration of the acoustic diaphragm 3 provided with the reinforcing member 10 used in the present embodiment is the same as that of the acoustic diaphragm described with reference to FIGS. Description is omitted.

  In the present invention, the configuration of the acoustic diaphragm is not limited to this. If the divided vibration of the sub dome 32 in the acoustic diaphragm of the electroacoustic transducer to be finally formed can be effectively prevented, the above-described application will be described. As exemplified in Modifications 1 to 4 of the acoustic diaphragm according to the invention, acoustic diaphragms of various shapes can be used.

  In the dynamic headphone unit 1 according to the present embodiment, the voice coil 4 is attached to the molded acoustic diaphragm 3 at a portion corresponding to the boundary between the main dome 31 and the sub dome 32 of the acoustic diaphragm 3 in the reinforcing member 10. This can be done by applying an organic solvent to the contact portion between the voice coil 4 and the reinforcing member 10 while pressing the voice coil 4. By applying the organic solvent, the hot melt adhesive at the contact portion of the reinforcing member 10 is dissolved, and the contact portion between the voice coil 4 and the reinforcing member 10 is covered with the dissolved hot melt adhesive. Then, the hot-melt adhesive is cured again by evaporating the organic solvent from the dissolved hot-melt adhesive, and the voice coil 4 is fixed to the acoustic diaphragm 3.

  In the application of the organic solvent to the contact portion between the acoustic diaphragm 3 and the voice coil 4 described above, it is sufficient that the hot melt adhesive at the contact portion is dissolved, and the organic material is applied to the portions other than the contact portion. Even if the solvent is applied, there is no problem as long as the shape of the reinforcing member 10 is not disturbed. Therefore, high work accuracy is not required. If the voice coil 4 is attached to the wrong position, the voice coil 4 can be easily detached from the acoustic diaphragm 3 by applying an organic solvent again or heating the attachment part. Since the operation can be performed again, loss of component materials due to an operation error can be suppressed.

  Further, in the dynamic headphone unit 1 which is an example of the electroacoustic transducer according to the present invention, the molded acoustic diaphragm 3 is fixed to the unit frame 2 by attaching an organic solvent to the outer peripheral edge reinforcing member 103 of the acoustic diaphragm 3. Is applied, the hot melt adhesive of the outer peripheral edge reinforcing member 103 is dissolved, the acoustic diaphragm 3 is placed on the unit frame 2, and the organic solvent is evaporated from the dissolved hot melt adhesive. Can do.

  In fixing the acoustic diaphragm 3 to the unit frame 2 described above, it is only necessary that the hot melt adhesive at the contact portion between the unit frame 2 and the acoustic diaphragm 3 is dissolved. Even if the organic solvent is applied, there is no problem as long as the shape of the reinforcing member 10 is not disturbed. Therefore, high work accuracy is not required. Further, when the acoustic diaphragm 3 is fixed in a wrong position, the acoustic diaphragm 3 can be easily detached from the unit frame 2 by applying an organic solvent again or heating the fixing portion. Since the work can be performed again, loss of parts material due to work mistakes can be suppressed.

  By using the electroacoustic transducer including the acoustic diaphragm according to the present invention as in the dynamic headphone unit 1 described above, generation of divided vibration of the sub-dome is prevented, and generation of abnormal noise is effectively prevented. .

  In addition, since the acoustic diaphragm can be designed and manufactured at a low cost, the design and manufacturing cost of the electroacoustic transducer including the acoustic diaphragm can be reduced.

  In the present embodiment, the dynamic headphone unit has been described as an example of the electroacoustic transducer. However, the present invention is not limited to this, and the present embodiment is not limited to this and may be used in various electroacoustic transducers such as a dynamic microphone unit and a dynamic speaker unit. The acoustic diaphragm can be used.

1 dynamic headphone unit 3 diaphragm 31 main dome 32 sub dome 34 material thin film 10 reinforcing member 101 main dome reinforcing member 102 sub dome reinforcing member 103 outer peripheral edge reinforcing member 104 reinforcing member pattern 15 mold

Claims (13)

A diaphragm base having a main dome and a sub dome surrounding the main dome;
A reinforcing member made of a hot-melt adhesive provided on the sub-dome;
Acoustic diaphragm with   The acoustic diaphragm according to claim 1, further comprising a second reinforcing member made of a hot-melt adhesive provided on the main dome.   The acoustic diaphragm according to claim 1, wherein the hot melt adhesive is soluble in an organic solvent.   The acoustic diaphragm according to claim 2 or 3, wherein the reinforcing member and the second reinforcing member are provided on one surface side of the diaphragm base.   The acoustic diaphragm according to claim 4, wherein the reinforcing member and the second reinforcing member are integrally provided. A method for producing an acoustic diaphragm comprising: a diaphragm body having a main dome and a sub dome surrounding the main dome; and a reinforcing member made of a hot melt adhesive provided on the sub dome,
A printing step of printing a reinforcing member pattern with the hot melt adhesive at a position corresponding to the sub dome of the material thin film;
Molding a material thin film on which the reinforcing member pattern is printed, and forming a diaphragm base having the main dome and the sub dome and the reinforcing member;
A method for manufacturing an acoustic diaphragm comprising:   The method for manufacturing an acoustic diaphragm according to claim 6, further comprising a curing step of curing the hot melt adhesive printed as the reinforcing member pattern.   The method for manufacturing an acoustic diaphragm according to claim 6 or 7, wherein in the printing step, a second reinforcing member pattern is further printed by the hot melt adhesive at a position corresponding to the main dome of the material thin film.   The method for manufacturing an acoustic diaphragm according to claim 8, wherein the reinforcing member pattern and the second reinforcing member pattern are printed on one surface side of the material thin film.   The method for manufacturing an acoustic diaphragm according to claim 9, wherein the reinforcing member pattern and the second reinforcing member pattern are printed together. The hot melt adhesive is soluble in an organic solvent, and the hot melt adhesive in a state dissolved in the organic solvent in the printing process is printed on the material thin film,
The method for producing an acoustic diaphragm according to claim 7, wherein the curing step is performed by evaporating an organic solvent of the hot melt adhesive printed on the material thin film. A magnetic circuit component;
A voice coil disposed in a magnetic gap formed by the magnetic circuit component;
An acoustic diaphragm to which the voice coil is fixed;
An electroacoustic transducer comprising:
The electroacoustic transducer according to any one of claims 1 to 5, wherein the acoustic diaphragm is an acoustic diaphragm.   The electroacoustic transducer according to claim 12, wherein the voice coil is fixed to the acoustic diaphragm with a hot melt adhesive.

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