JP2010062972A - Manufacturing method for speaker diaphragm, and speaker diaphragm manufactured by the manufacturing method, speaker using the speaker diaphragm, and electronic device and moving body using the speaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the stiffness of a speaker diaphragm by increase in weight to an extent which does not affect the characteristics of the diaphragm, in order to raise the high pass threshold frequency. <P>SOLUTION: As for the speaker diaphragm manufactured by paper-making method, fine natural fiber is applied to or deposited on a section coupled to a voice coil bobbin. Thus, the stiffness of the speaker diaphragm can be improved by increase in weight to an extent which does not affect the characteristics of the diaphragm, and the high pass threshold frequency can be raised. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a method of manufacturing a speaker diaphragm used in various audio equipment and video equipment, a speaker diaphragm manufactured by the manufacturing method, a speaker and a stereo set using the speaker diaphragm, The present invention relates to an electronic device such as a television set and a moving body such as an automobile.

  In the recent audio industry and the automobile industry equipped with audio equipment, the quality of sound reproduced from speakers has improved dramatically due to the spread of digital equipment.

  The main trends for speakers in these industries are higher sound quality, smaller size, and thinner thickness. In order to improve the sound quality of a speaker, a papermaking diaphragm is used for the speaker. Conventionally, a material obtained by beating kraft pulp from conifers with a beater or the like has been used as a material for the papermaking diaphragm.

  On the other hand, if the diaphragm is reduced in size or thickness to make the speaker smaller or thinner, the rigidity of the diaphragm is lowered, and the high frequency limit frequency of the speaker is lowered to hinder high sound quality. there were.

Conventionally, in order to improve the rigidity of the diaphragm, the material of the diaphragm has been impregnated with a resin such as epoxy (see, for example, Patent Document 1).
JP 58-156296 A

  However, when the material of the diaphragm is impregnated with a resin such as epoxy, the weight of the diaphragm as a whole increases, so that the characteristics of the diaphragm are lowered and cost is increased. Moreover, it is difficult to further improve the high-frequency limit frequency only by making the diaphragm material rigid. Furthermore, when a resin such as epoxy is used to improve the rigidity of the diaphragm, there are problems such as the operator's hand being scratched and a large amount of solvent being required and costly.

  An object of the present invention is to improve the rigidity of a diaphragm for a speaker with a weight increase that does not affect the characteristics of the diaphragm, and to improve the high-frequency limit frequency. Moreover, it aims at protecting a worker's safety and reducing manufacturing cost.

  According to another aspect of the present invention, there is provided a method for manufacturing a speaker diaphragm, comprising: applying or depositing refined natural fibers to a portion of a speaker diaphragm manufactured by papermaking that is coupled to a voice coil bobbin. Features.

  A speaker diaphragm according to another aspect of the present invention is characterized in that, in a speaker diaphragm manufactured by papermaking, fine natural fibers are coated or deposited on a portion to be coupled with a voice coil bobbin. To do.

  A speaker according to another aspect of the present invention includes a frame coupled to a magnetic circuit, a voice coil having one end inserted in a magnetic gap of the magnetic circuit, a voice coil bobbin around which the voice coil is wound, A speaker having a diaphragm coupled to an outer peripheral portion and coupled to a voice coil bobbin, wherein fine natural fibers are coated or deposited on a portion of the diaphragm coupled to the voice coil bobbin. To do.

  An electronic apparatus according to another aspect of the present invention includes a frame coupled to a magnetic circuit, a voice coil having one end inserted in a magnetic gap of the magnetic circuit, a voice coil bobbin around which the voice coil is wound, and an outer periphery of the frame A portion of a diaphragm coupled to a voice coil bobbin in an electronic device including a speaker having a diaphragm coupled to a voice coil bobbin and an amplification circuit for amplifying an input signal to the speaker Is characterized in that fine natural fibers are applied or deposited.

  A moving body according to another aspect of the present invention includes a frame coupled to a magnetic circuit, a voice coil having one end inserted in a magnetic gap of the magnetic circuit, a voice coil bobbin around which the voice coil is wound, and an outer periphery of the frame In a moving body provided with a speaker having a diaphragm coupled to the other end of the voice coil, a refined natural fiber is applied to a portion of the diaphragm coupled to the voice coil bobbin. Or deposited.

  As described above, according to the present invention, the rigidity of the loudspeaker diaphragm can be improved by increasing the weight so as not to affect the characteristics of the diaphragm, and the high frequency limit frequency can be improved. Furthermore, it is possible to reduce worker safety and cost.

(Embodiment 1)
Hereinafter, one aspect of the present invention will be described with reference to the drawings.

  FIG. 1 is a process chart showing a method for manufacturing a diaphragm for a speaker by a papermaking method in an embodiment of the present invention.

  As shown in FIG. 1, first, the material for the diaphragm for the speaker is put into a beater containing water and finely beaten by a beating process over several days.

  Next, this beaten material is made up on a mold and a metal mesh placed on it by a papermaking method, and only moisture is discharged by sucking from below, so that it can be used as a diaphragm for speakers. To form.

Thereafter, the portions other than the central portion of the speaker diaphragm are masked. Then, a treatment liquid in which natural fibers refined to have an average fiber length of 0.5 mm or more and a BET specific surface area of 1 m ² / g or more is diluted with water is spray-coated or deposited on a diaphragm for speakers. . Since the speaker diaphragm is masked at portions other than the central portion, the processing liquid is applied or deposited on the central portion of the speaker diaphragm that has not been masked. Since the mold is sucked, only the moisture is discharged from the natural fiber treatment liquid applied or deposited on the central portion of the speaker diaphragm.

  Next, the water remaining without being discharged is heated and pressurized to evaporate.

  And the outer peripheral part which becomes unnecessary among the diaphragms for speakers, and the center hole part for inserting a voice coil bobbin are punch-processed with a metal mold | die. The central hole portion is provided by removing a part of the central portion of the speaker diaphragm on which the natural fiber treatment liquid is applied or deposited.

  Thus, the speaker diaphragm according to the manufacturing method of the present invention is completed.

  In addition, here, a method for manufacturing a diaphragm for a speaker using conventional papermaking, in which one embodiment of the present invention is applied, is shown. However, the present invention is not limited to this, and is applicable as long as it includes a papermaking process. In addition, the remaining portion of the central portion of the speaker diaphragm that has not been punched is coupled to the voice coil bobbin.

  Further, the spray application may be performed at the same time as or after the paper making process, and can be performed even after the pressurizing process and the punching process.

  Here, in the present invention, as a method of refining natural fibers, a method of beating with a bead mill after beating with a biaxial kneader is used. In this construction method, the material can be miniaturized at a lower cost and in a shorter time than the miniaturization method using a general beater. That is, it is possible to efficiently produce a fiber having a large reinforcing effect when applied to a speaker diaphragm. In addition, as a method of refining natural fibers, a method of beating with a bead mill instead of beating with a biaxial kneader may be used. In this case, the work process can be shortened and the cost can be reduced as compared with the method of beating with a bead mill after beating with a biaxial kneader.

In addition, it is desirable that the refined natural fiber has an average fiber length of 0.7 mm or more and 1.5 mm or less from the viewpoint of further improving the rigidity of the applied surface and the efficiency of producing the refined fiber. Further, the BET specific surface area is preferably 1 m ² / g or more from the viewpoint of the effect of improving the rigidity. If the BET specific surface area of the natural fiber is 1 m ² / g or more, the viscosity is low, so that spraying is difficult to block when spraying on the diaphragm, yield can be improved, and working time can be shortened.

  Moreover, it is desirable that the natural fiber to be applied is bamboo fiber. The reason for this is that bamboo fiber has high rigidity as a fiber and has a multilayer structure with a four-layer surface, which is suitable in that the surface is feathered by frictional force, and is also good in terms of the environment. And the like.

  Here, the specific example of the manufacturing method of the refined bamboo fiber in this invention and the manufacturing method of the diaphragm for speakers which applied the refined bamboo fiber by spraying is shown below.

700 g of bamboo fibers having an average fiber length of about 10 cm are treated with a pressure kneader having a volume of 3 liters at 25 rpm for 20 minutes and beaten. Thereafter, it is made into a 5% aqueous dispersion, treated with a 3 liter bead mill using glass beads for 20 minutes, and further beaten. The average fiber length of the beaten fiber was 0.8 mm, and the BET specific surface area was 2.11 m ² / g.

  Then, a solution obtained by diluting this treatment solution with water to 2% was placed on a sucked papermaking mold and spray-coated on a papermaking diaphragm in which portions other than the central portion were masked. Thereafter, it was dried at 160 ° C. for 5 minutes. Then, a part of the center of the papermaking diaphragm was punched to complete a speaker diaphragm. The spray coating may be performed after the papermaking diaphragm is dried, or may be performed before the papermaking diaphragm is dried. When spraying is applied before the papermaking diaphragm is dried, one drying step is omitted, so that the work process for manufacturing the speaker diaphragm can be shortened.

  The loudspeaker diaphragm manufactured by this method has an increase in weight of only about 0.5 g as compared with the loudspeaker diaphragm not sprayed with finely sized bamboo fibers. If the weight increases to such an extent, the influence on the characteristics of the diaphragm can be suppressed.

As described above, according to the manufacturing method of the present embodiment, the refined natural fiber, particularly bamboo fiber, is spray-applied only to the central portion of the speaker diaphragm that is coupled to the voice coil. It is possible to manufacture a speaker diaphragm having improved rigidity while suppressing it, and the high frequency limit frequency of the speaker diaphragm can be improved without greatly affecting the characteristics of the speaker diaphragm. . In addition, according to the manufacturing method of the present embodiment, natural fibers can be refined by a method of beating with a biaxial kneader and then beating with a bead mill, so that the fibers were refined in a short time at a lower cost than before. Natural fibers can be obtained. In addition, since a natural fiber is used without using a resin such as epoxy in order to improve the rigidity of the diaphragm, the operator's hand is not damaged and a large amount of solvent is not required. Therefore, not only can the rigidity of the diaphragm be improved, but also operator safety and cost reduction can be achieved.

(Embodiment 2)
Hereinafter, other aspects of the present invention will be described with reference to the drawings.

  FIG. 2 shows a plan view of the speaker diaphragm 10 manufactured by the manufacturing method of the first embodiment. The speaker diaphragm 10 shown in FIG. 2 has a track shape as an outer shape. The speaker diaphragm 10 has a center hole portion 11 for inserting a voice coil bobbin, and a center portion 12 on which natural fibers refined by the manufacturing method of the first embodiment are applied or deposited.

  In FIG. 2, the track shape is shown as the shape of the speaker diaphragm 10. However, the shape may be any shape such as a rectangular shape, a rectangular shape, an elliptical shape, or a circular shape.

  According to the present embodiment, since the rigidity of the speaker diaphragm is improved while an increase in the weight of the speaker diaphragm is suppressed, the reproduction limit frequency of the speaker diaphragm can be improved. .

(Embodiment 3)
Hereinafter, other aspects of the present invention will be described with reference to the drawings.

  FIG. 3 shows a cross-sectional view of the speaker 20 of the present embodiment.

  As shown in FIG. 3, the speaker 20 includes an inner magnet type magnetic circuit 24 in which a magnetized magnet 21 is sandwiched between an upper plate 22 and a yoke 23. A frame 26 is coupled to the upper plate 22 of the magnetic circuit 24. The outer periphery of the diaphragm 10 for a speaker according to the second embodiment is bonded to the peripheral portion of the frame 26 via an edge 27. Then, one end of the voice coil 28 is inserted into the center hole portion 11 of the diaphragm 10 for the speaker, and one end of the voice coil 28 and the center portion 12 of the diaphragm 10 for the speaker are coupled. The other end of the voice coil 28 is disposed in the magnetic gap 25 of the magnetic circuit 24 via a gap.

  In the present embodiment, the magnetic circuit 24 is an inner magnet type, but may be an outer magnet type.

  In this embodiment, the speaker diaphragm 10 and the edge 27 are separate from each other. However, the present invention can also be applied to a small speaker in which the speaker diaphragm 10 and the edge 27 are integrated. is there.

  Here, the frequency-sound pressure characteristics of the speaker 20 using the speaker diaphragm 10 with the central portion 12 spray-coated and the speaker using the speaker diaphragm with the central portion not spray-coated are measured. Both characteristics were compared. The sound pressure deviation width of the speaker using the speaker diaphragm not coated with spray is 12 dB, whereas the sound pressure deviation width of the speaker 20 using the sprayed speaker diaphragm 10 is It was 5 dB. In other words, the sound pressure deviation improved by 7 dB with a weight increase of only 0.5 g.

  According to the present embodiment, since the rigidity of the speaker diaphragm is improved while an increase in the weight of the speaker diaphragm is suppressed, the reproduction limit frequency of the speaker diaphragm can be improved. . Therefore, the speaker using the diaphragm for the speaker can provide a deep bass that is tightened in the low frequency range, and has a clear sound with reduced resonance specific to the high frequency range caused by insufficient rigidity of the diaphragm for the speaker. Can be provided.

(Embodiment 4)
Hereinafter, other aspects of the present invention will be described with reference to the drawings.

  FIG. 4 shows an external view of an audio mini-component system 30 which is an electronic apparatus according to the present embodiment.

  As shown in FIG. 4, the speaker system 32 is configured by incorporating the speaker 20 of the third embodiment into an enclosure 31. The speaker system 32 includes an amplifier 33 that amplifies an electric signal input to the speaker 20 and a player 34 that outputs a source input to the amplifier 33.

  According to the speaker system of the present embodiment, it is possible to obtain a deep bass sound that is tight in the low sound range and a clear and powerful sound quality in the high sound range. Furthermore, the speaker system can be excellent in terms of quality and reliability.

(Embodiment 5)
Hereinafter, other aspects of the present invention will be described with reference to the drawings.

  FIG. 5 shows a cross-sectional view of an automobile 40 which is a moving body of the present embodiment.

  As shown in FIG. 5, the automobile 20 is configured by incorporating the speaker 20 of Embodiment 3 into a rear tray or a front panel and using it as a part of car navigation or car audio.

  According to this embodiment, the sound pressure level in the high sound range of the speaker can be improved, and a clear and powerful sound quality can be obtained in the high sound range. Furthermore, it can be excellent in terms of quality and reliability, and the performance and quality of a moving body such as an automobile equipped with a speaker can be improved.

  A speaker diaphragm manufacturing method of the present invention, a speaker diaphragm manufactured by the manufacturing method, a speaker using the speaker diaphragm, an electronic apparatus such as an audiovisual apparatus or an information communication apparatus, and Useful for devices such as automobiles.

Process chart which shows the manufacturing method of the diaphragm for speakers in Embodiment 1 of this invention Plan view of a diaphragm for a speaker in Embodiment 2 of the present invention Sectional drawing of the speaker in Embodiment 3 of this invention External view of the electronic device in Embodiment 4 of this invention Sectional drawing of the moving body in Embodiment 5 of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Speaker diaphragm 11 Center hole part 12 Center part 20 Speaker 21 Magnet 22 Upper plate 23 Yoke 24 Magnetic circuit 25 Magnetic gap 26 Frame 27 Edge 28 Voice coil 30 Mini component system 31 Enclosure 32 Speaker system 33 Amplifier 34 Player 40 Automobile

Claims (10)

A method of manufacturing a speaker diaphragm, comprising: applying or depositing fine natural fibers on a portion of a speaker diaphragm manufactured by papermaking to be coupled to a voice coil bobbin. 2. The method for manufacturing a speaker diaphragm according to claim 1, wherein the natural fiber is bamboo fiber. The natural fibers, the manufacturing method of the diaphragm of the speaker of claim 1, a BET specific surface area is equal to or is 1 m ² / g or more. The method for manufacturing a speaker diaphragm according to claim 1, wherein the natural fiber is a secondary material for locally improving the rigidity of the diaphragm main body. 2. The method for manufacturing a diaphragm for a speaker according to claim 1, wherein the natural fiber is beaten and refined by at least a bead mill. 6. The method for manufacturing a diaphragm for a speaker according to claim 5, wherein the natural fibers are beaten by a biaxial kneader before being beaten by a bead mill. A loudspeaker diaphragm manufactured by making paper, wherein fine natural fibers are coated or deposited on a portion coupled to a voice coil bobbin. A frame coupled to a magnetic circuit;
A voice coil having one end inserted in the magnetic gap of the magnetic circuit;
A voice coil bobbin around which this voice coil is wound,
In a speaker including a diaphragm coupled to the outer periphery of the frame and coupled to the voice coil bobbin,
The speaker is characterized in that fine natural fibers are applied or deposited on a portion of the diaphragm coupled to the voice coil bobbin. A frame coupled to a magnetic circuit; a voice coil having one end inserted in a magnetic gap of the magnetic circuit; a voice coil bobbin around which the voice coil is wound; and a voice coil bobbin coupled to an outer periphery of the frame A speaker having a diaphragm coupled to
In an electronic device comprising at least an amplification circuit for amplifying an input signal to the speaker,
An electronic apparatus characterized in that a refined natural fiber is applied or deposited on a portion of the diaphragm coupled to the voice coil bobbin. A frame coupled to a magnetic circuit; a voice coil having one end inserted in a magnetic gap of the magnetic circuit; a voice coil bobbin around which the voice coil is wound; and a voice coil coupled to an outer periphery of the frame In a moving body provided with a speaker having a diaphragm coupled to the other end of
A moving body characterized in that fine natural fibers are applied or deposited on a portion of the diaphragm coupled to the voice coil bobbin.

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