JP3109296B2 - Speaker diaphragm - Google Patents
Speaker diaphragmInfo
- Publication number
- JP3109296B2 JP3109296B2 JP04316835A JP31683592A JP3109296B2 JP 3109296 B2 JP3109296 B2 JP 3109296B2 JP 04316835 A JP04316835 A JP 04316835A JP 31683592 A JP31683592 A JP 31683592A JP 3109296 B2 JP3109296 B2 JP 3109296B2
- Authority
- JP
- Japan
- Prior art keywords
- diaphragm
- speaker
- fiber
- voice coil
- chitin
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Compositions Of Macromolecular Compounds (AREA)
- Paper (AREA)
- Diaphragms For Electromechanical Transducers (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は音響出力機器等に用いる
スピーカ用振動板に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diaphragm for a speaker used for an audio output device or the like.
【０００２】[0002]
【従来の技術】近年、オーディオ関連業界においては、
再生音楽ソースのデジタル化に伴い、音響出力機器とし
てのスピーカの特性において、従来よりもさらに出力音
圧、歪み率、平坦性に優れた高音質のスピーカが望まれ
ており、音響特性を左右するスピーカ用振動板はますま
す重要視されている。2. Description of the Related Art In recent years, in the audio-related industry,
With the digitization of playback music sources, there is a demand for a high-quality speaker with better output sound pressure, distortion rate, and flatness than ever before in terms of the characteristics of a speaker as an audio output device. Speaker diaphragms are becoming increasingly important.
【０００３】以下、上述の従来のスピーカの例につい
て、その動作を説明する。スピーカは振動板、ボイスコ
イルボビン、ボイスコイルなどの振動系と、マグネッ
ト、ポール、プレート、ヨークよりなる磁気回路系から
なる。Hereinafter, the operation of the above-described conventional speaker will be described. The speaker includes a vibration system such as a diaphragm, a voice coil bobbin, and a voice coil, and a magnetic circuit system including a magnet, a pole, a plate, and a yoke.
【０００４】この振動板はボイスコイルボビンに固着さ
れ、ボイスコイルボビンの先端に設けられたボイスコイ
ルが磁気回路の磁気ギャップに挿入されて構成されてい
る。The diaphragm is fixed to a voice coil bobbin, and a voice coil provided at the tip of the voice coil bobbin is inserted into a magnetic gap of a magnetic circuit.
【０００５】以上のように構成されたスピーカについ
て、以下その動作について説明する。一様な磁場の中に
あるボイスコイルに音声電流が流れるとボイスコイルに
上下方向の電磁力が発生し、電流に応じて振動する。こ
の振動が振動板に伝えられ、振動板から音波として放射
される。The operation of the loudspeaker configured as described above will be described below. When a voice current flows through a voice coil in a uniform magnetic field, a vertical electromagnetic force is generated in the voice coil, and the voice coil vibrates according to the current. This vibration is transmitted to the diaphragm, and emitted from the diaphragm as sound waves.
【０００６】[0006]
【発明が解決しようとする課題】スピーカ用振動板は、
使用する周波数帯域にわたってピストン運動することが
理想とされるが、振動中に振動板が変形したり分割振動
が生ずると、音圧−周波数特性、歪み率、位相特性等が
劣化し、高忠実再生の妨げとなる。また、従来多く用い
られているパルプを用いた振動板のもつＥ／ρ（ただ
し、Ｅ：弾性率、ρ：密度）が小さいため、図４に示す
ように高域共振周波数が低く、スピーカが高域まで再生
できないという欠点があった。SUMMARY OF THE INVENTION A speaker diaphragm is
Ideally, the piston moves over the frequency band to be used, but if the diaphragm is deformed or vibrates during vibration, the sound pressure-frequency characteristics, distortion rate, phase characteristics, etc. will deteriorate, and high fidelity reproduction will occur. Hinders Further, since the diaphragm using pulp, which has been widely used in the past, has a small E / ρ (E: elastic modulus, ρ: density), the high-band resonance frequency is low as shown in FIG. There was a drawback that it was not possible to reproduce up to high frequencies.
【０００７】従来、このパルプを用いた振動板の欠点を
補うため、補強材として高弾性率の強化繊維を混抄し、
樹脂バインダーでパルプ繊維と結合させたり、高弾性率
の樹脂を含浸する手法が行われてきた。Conventionally, in order to compensate for the drawbacks of a diaphragm using this pulp, a reinforcing fiber having a high elastic modulus is mixed as a reinforcing material.
Techniques of bonding with pulp fibers with a resin binder or impregnating with a resin having a high elastic modulus have been used.
【０００８】しかし、スピーカは、車載需要の増大とと
もに使用環境において苛酷になり、特に高温下での使用
を余儀なくされてきている。さらに、再生機器のアンプ
出力の増大化とともに、大入力時のボイスコイルの発熱
量も増大し、ボイスコイル付近での温度環境も厳しいも
のとなってきている。However, the loudspeaker has become severe in a use environment with an increase in demand for mounting on a vehicle, and has been inevitably used especially at a high temperature. Further, with an increase in the amplifier output of the playback device, the amount of heat generated by the voice coil at the time of a large input also increases, and the temperature environment near the voice coil has become severe.
【０００９】これに伴って、パルプを用いた振動板の強
化繊維、バインダー、または含浸材の各々において、耐
熱性の低いものではパルプを用いた振動板の欠点を補う
には問題があった。Along with this, there has been a problem in compensating for the drawbacks of the pulp-based diaphragm, if the reinforcing fiber, binder, or impregnating material of the pulp-based diaphragm has low heat resistance.
【００１０】本発明は上記従来の問題点を解決するもの
で、振動中に振動板が変形したり分割振動を生ぜず、高
域共振周波数が高く、音圧−周波数特性、歪み率、位相
特性が優れ、かつ耐熱性、耐溶剤性、耐候性の高いスピ
ーカ用振動板を提供することを目的とする。The present invention solves the above-mentioned conventional problems, in which the diaphragm does not deform or generate divided vibration during vibration, the high-band resonance frequency is high, the sound pressure-frequency characteristic, the distortion rate, and the phase characteristic It is an object of the present invention to provide a speaker diaphragm having excellent heat resistance, solvent resistance and weather resistance.
【００１１】[0011]
【課題を解決するための手段】この目的を達成するため
に本発明のスピーカ用振動板は、キチン質からなる繊維
の表面を脱アセチル化し、キトサン層を形成した繊維を
単独で抄造、あるいは異なる材料と混抄し、所定の形状
に成形するという構成、さらにはバインダーとして分子
内にエポキシ基を有する合成樹脂のモノマーあるいはオ
リゴマーの水溶液もしくはエマルジョン等の水和物を用
いて抄造成形した構成としたものである。In order to achieve this object, a speaker diaphragm according to the present invention is characterized in that the surface of a chitin fiber is deacetylated to produce a chitosan layer-formed fiber by itself or differently. A composition formed by mixing with materials and molding into a predetermined shape, and a composition formed by using a hydrate such as an aqueous solution or emulsion of a monomer or oligomer of a synthetic resin having an epoxy group in the molecule as a binder. It is.
【００１２】[0012]
【作用】この構成によると、キチン質が化学構造上パル
プを構成するセルローズと同様の骨格を有しており、高
い弾性率を有しているため、上記した材料を用いると弾
性率が大きくなり、これを振動板として用いた場合、振
動板の曲げ剛性が非常に大きく、振動中に振動板が変形
したり分割共振が生じることがきわめて少ない。また基
材として、キチン質からなる繊維の表面を脱アセチル化
し、キトサン層を形成した繊維を単独で抄造した構成
物、あるいはその他の材料と混抄した構成物を用いてい
るため、比弾性率Ｅ／ρ（ただし、Ｅ：弾性率、ρ：密
度）が大きく、これを振動板として用いた場合、スピー
カの再生帯域が高音側にのび、すぐれた音圧−周波数特
性、歪み率、位相特性を持つスピーカを得ることができ
る。According to this structure, chitin has a chemical structure similar to that of cellulose constituting pulp and has a high modulus of elasticity. When this is used as a diaphragm, the diaphragm has a very high bending rigidity, so that the diaphragm is unlikely to be deformed or split resonance occurs during vibration. Further, since the surface of the chitin fiber is deacetylated and the fiber having the chitosan layer formed is formed by itself or mixed with other materials, the specific elastic modulus E is used as the base material. / Ρ (E: elastic modulus, ρ: density) is large, and when this is used as a diaphragm, the reproduction band of the speaker extends to the high frequency side, and excellent sound pressure-frequency characteristics, distortion rate, and phase characteristics are obtained. Speaker can be obtained.
【００１３】また、キチン質は、非常に大きい内部損失
を持っているため、これを単独で抄造した振動板、ある
いはその他の材料と混抄した振動板は、これを振動板と
して用いた場合、スピーカの音圧−周波数特性の山谷を
平坦化し、忠実な音響特性を得ることができる。[0013] Further, since chitin has a very large internal loss, a diaphragm made by itself or a diaphragm mixed with other materials, when this is used as a diaphragm, causes a loudspeaker. Of the sound pressure-frequency characteristics of the first embodiment can be flattened, and faithful acoustic characteristics can be obtained.
【００１４】さらに、このスピーカ用振動板は、天然高
分子のキチン質の繊維を用いているため、耐溶剤性、耐
熱性、耐候性に優れ、これを振動板として用いた場合、
スピーカに大きな入力信号を入れることができ、また苛
酷な条件下でのスピーカの使用に耐え得る。Further, since this speaker diaphragm uses natural polymer chitin fibers, it has excellent solvent resistance, heat resistance and weather resistance. When this is used as a diaphragm,
A large input signal can be input to the speaker, and the speaker can be used under severe conditions.
【００１５】[0015]
【実施例】（実施例１）以下、本発明の一実施例のスピ
ーカ用振動板について図面を用いて説明する。(Embodiment 1) A speaker diaphragm according to an embodiment of the present invention will be described below with reference to the drawings.
【００１６】本発明の一実施例におけるスピーカ用振動
板は、図１，図２に示すように甲殻類の外皮形成物の主
成分であるキチン質を繊維状にしたものの表面を脱アセ
チル化し、キトサン層を形成した繊維３を単独で抄造し
た構成物、あるいは他の材料と混抄した構成物を振動板
の形状に成形した振動板本体１の周縁部にフリーエッジ
２を貼付けて構成されている。このスピーカ用振動板
は、ボイスコイルボビンに固着され、ボイスコイルボビ
ンの先端に設けられたボイスコイルが磁気回路の磁気ギ
ャップに挿入されてスピーカを構成する。As shown in FIGS. 1 and 2, the speaker diaphragm in one embodiment of the present invention is obtained by deacetylating the surface of a fibrous chitin material which is a main component of a crustacean shell-forming substance. A free edge 2 is attached to the periphery of a diaphragm main body 1 in which a composition obtained by individually forming the fiber 3 having a chitosan layer or a composition mixed with another material is formed into a diaphragm shape. . The speaker diaphragm is fixed to a voice coil bobbin, and a voice coil provided at the tip of the voice coil bobbin is inserted into a magnetic gap of a magnetic circuit to constitute a speaker.
【００１７】以上のように構成されたスピーカについ
て、以下その動作について説明する。スピーカは、振動
板、ボイスコイルボビン、ボイスコイルなどの振動系と
マグネット、ポール、プレート、ヨークよりなる磁気回
路系よりなる。一様な磁場の中にあるボイスコイルに音
声電流が流れると、ボイスコイルに上下方向の電磁力が
発生し電流に応じて振動する。この振動を正しくスピー
カ用振動板に伝え、音波として放出される。The operation of the loudspeaker configured as described above will be described below. The speaker includes a vibration system such as a diaphragm, a voice coil bobbin, and a voice coil, and a magnetic circuit system including a magnet, a pole, a plate, and a yoke. When a voice current flows through a voice coil in a uniform magnetic field, a vertical electromagnetic force is generated in the voice coil, and the voice coil vibrates according to the current. This vibration is correctly transmitted to the speaker diaphragm and emitted as a sound wave.
【００１８】また、ボイスコイルに流れる音声電流は、
電磁力を発生させるとともに多くは熱エネルギーとして
変換される。このときのボイスコイルの温度は入力され
る音声電流の大きさに応じて高くなり、しばしば２００
℃を越える。そしてこの熱は、ボイスコイルボビンを通
じて振動板本体１にも伝達されるため、熱変形温度の高
くない材料で構成された振動板は変形をきたし、発生す
る音が歪んだりノイズの発生する原因となるが本発明の
スピーカ用振動板は変形をきたすことはなく歪み、ノイ
ズの発生は阻止できる。The voice current flowing through the voice coil is:
While generating electromagnetic force, most are converted as heat energy. At this time, the temperature of the voice coil increases in accordance with the magnitude of the input voice current, and is often 200
Exceeds ° C. Since this heat is also transmitted to the diaphragm main body 1 through the voice coil bobbin, the diaphragm made of a material having a low thermal deformation temperature is deformed, and the generated sound is distorted or causes noise. However, the speaker diaphragm of the present invention is not deformed and is distorted, so that generation of noise can be prevented.
【００１９】次に、スピーカ用振動板の製造方法につい
て述べると、甲殻類の外皮形成物の主成分であるキチン
質を、溶媒、たとえばジメチルアセトアミド、Ｎ−メチ
ル−２−ピロリドン、リチウムクロライド等を混合した
溶媒に溶解し、その溶液より湿式紡糸法により、０．７
〜１デニールの太さの繊維を紡糸する。その後、濃アル
カリ処理を行って表面を脱アセチル化してキトサン層を
形成する。Next, a method for producing a speaker diaphragm will be described. Chitin, which is the main component of the crustacean shell-forming product, is treated with a solvent such as dimethylacetamide, N-methyl-2-pyrrolidone, lithium chloride or the like. It was dissolved in a mixed solvent, and the solution was subjected to wet spinning by 0.7 wt.
Spin fibers of ~ 1 denier thickness. Then, the surface is deacetylated by performing a concentrated alkali treatment to form a chitosan layer.
【００２０】この繊維を３〜１０mmの長さに切断し、水
中に０．１〜０．３％分散させ、６０〜８０メッシュの
金網を用いて抄造した後、加熱プレス、熱風圧乾燥機等
で所定の振動板形状に成形する。このとき、分散させる
水を塩酸、酢酸等でｐＨ７〜５の弱酸性にするとキトサ
ン層が膨潤し易くなり、乾燥成形時に繊維どうしが接着
して強固な結合を生じ易く、振動板本体１の弾性率が向
上する。The fiber is cut to a length of 3 to 10 mm, dispersed in water in a concentration of 0.1 to 0.3%, and formed using a wire mesh of 60 to 80 mesh, and then heated, pressed with a hot air dryer or the like. To form a predetermined diaphragm shape. At this time, if the water to be dispersed is made weakly acidic with a pH of 7 to 5 using hydrochloric acid, acetic acid or the like, the chitosan layer is easily swelled, and the fibers are easily adhered to each other at the time of dry molding to form a strong bond. The rate is improved.
【００２１】（実施例２）実施例１に示したキチン質繊
維を叩解した未晒しクラフトパルプに対して重量比で１
０〜１５％加え、この混合物を水中に重量比で０．１〜
０．３％分散させ実施例１と同様の方法にて抄造、成形
する。Example 2 The chitinous fiber shown in Example 1 was beaten and unbleached kraft pulp at a weight ratio of 1 to 1.
0 to 15%, and the mixture is added in water in a weight ratio of 0.1 to 0.1%.
Disperse 0.3%, and form and mold in the same manner as in Example 1.
【００２２】叩解したクラフトパルプは、その表面がフ
ィブリル化しており、抄造時にその表面が比較的滑らか
なキチン質繊維と程よく絡み合い、繊維どうしの結合が
密になって成形物の弾性率がさらに向上する。The beaten kraft pulp has a fibrillated surface, and the surface is moderately entangled with relatively smooth chitinous fibers during papermaking, whereby the fibers are tightly bonded to each other to further improve the elasticity of the molded product. I do.
【００２３】（実施例３）実施例２に示した材料を水中
に分散させた後、アルキルケテンダイマー、ポリアミド
ポリアミン−エピクロルヒドリン樹脂等をバインダーと
して添加し、実施例１と同様の方法にて抄造、成形す
る。(Example 3) After dispersing the material shown in Example 2 in water, an alkyl ketene dimer, a polyamide polyamine-epichlorohydrin resin and the like were added as a binder, and papermaking was performed in the same manner as in Example 1. Molding.
【００２４】このとき、加熱乾燥中に、ポリアミドポリ
アミン−エピクロルヒドリン中のエポキシ基とキチン繊
維表面のキトサン中のアミノ基およびクラフトパルプを
構成するセルローズ中の水酸基が化学反応して強固な結
合を生じ、成形物の弾性率がさらに向上する。At this time, during the heating and drying, the epoxy group in the polyamide polyamine-epichlorohydrin, the amino group in the chitosan on the chitin fiber surface, and the hydroxyl group in the cellulose constituting the kraft pulp undergo a chemical reaction to form a strong bond, The elastic modulus of the molded product is further improved.
【００２５】以上のように本実施例によれば、甲殻類の
外皮構成物の主成分であるキチン質を繊維状にしたもの
の表面を脱アセチル化し、キトサン層を形成した繊維を
単独で抄造、あるいは異なる材料と混抄した構成物を振
動板の形状に成形して用いたスピーカ用振動板は、振動
板の変形、分割振動が生ぜず図３に示すような良好な音
響特性が得られ、パルプ製コーン型振動板と比較して歪
み率を２２dB低下させることができる。As described above, according to the present embodiment, chitin, which is the main component of the shell composition of the crustacean, is made into a fibrous form, and the surface is deacetylated to produce a fiber having a chitosan layer alone. Alternatively, a diaphragm for a loudspeaker in which a composition mixed with a different material is formed into the shape of a diaphragm is used, and good acoustic characteristics as shown in FIG. 3 are obtained without causing deformation and divided vibration of the diaphragm. The distortion rate can be reduced by 22 dB as compared with the cone type diaphragm.
【００２６】音圧−周波数特性の山谷も±３dBとパルプ
の振動板と比較して、約±３dB低下させることができ
た。The peaks and valleys of the sound pressure-frequency characteristics were also ± 3 dB, which was about ± 3 dB lower than that of the pulp diaphragm.
【００２７】本発明で用いたキチン質繊維を用いたスピ
ーカ用振動板と従来用いられてきたパルプよりなるスピ
ーカ用振動板の物性値を（表１）に示す。The physical properties of the speaker diaphragm using chitin fibers used in the present invention and the speaker diaphragm made of pulp conventionally used are shown in Table 1.
【００２８】[0028]
【表１】 [Table 1]
【００２９】[0029]
【発明の効果】以上のように本発明は、甲殻類の外皮構
成物の主成分であるキチン質を繊維状にしたものの表面
を脱アセチル化し、キトサン層を形成した繊維を単独で
抄造、あるいは異なる材料と混抄した構成物を成形し、
スピーカ用振動板としたもので、歪み率が小さく、高域
共振周波数が高く、良好な音響特性と音質を有し、また
耐熱性の高い、耐溶剤性、耐候性の高い、かつ耐入力の
高い、音響出力の大きなスピーカを得ることができ、良
好な音響特性及び音質と高い信頼性を有するスピーカを
実現できるものである。As described above, according to the present invention, chitin, which is the main component of the shell composition of crustaceans, is made into a fibrous form, the surface of which is deacetylated, and a fiber having a chitosan layer is formed alone, or Forming a composition mixed with different materials,
A speaker diaphragm with low distortion, high high-frequency resonance, good acoustic and sound quality, high heat resistance, high solvent resistance, high weather resistance, and high input resistance. It is possible to obtain a speaker having a high sound output and a high sound output, and to realize a speaker having good acoustic characteristics and sound quality and high reliability.
【図１】本発明のスピーカ用振動板の一実施例を示す断
面図FIG. 1 is a cross-sectional view showing one embodiment of a speaker diaphragm of the present invention.
【図２】同要部の拡大断面図FIG. 2 is an enlarged cross-sectional view of the main part.
【図３】同スピーカ用振動板を用いたスピーカの音圧−
周波数特性図FIG. 3 shows a sound pressure of a speaker using the speaker diaphragm.
Frequency characteristic diagram
【図４】従来のスピーカ用振動板を用いたスピーカの音
圧−周波数特性図FIG. 4 is a sound pressure-frequency characteristic diagram of a speaker using a conventional speaker diaphragm.
１ 振動板本体 ２ フリーエッジ ３ 繊維 1 Diaphragm body 2 Free edge 3 Textile
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平５−183984（ＪＰ，Ａ) 特開 平４−70099（ＪＰ，Ａ) 特開 平３−232400（ＪＰ，Ａ) 特開 平３−229600（ＪＰ，Ａ) 特開 平４−213300（ＪＰ，Ａ) 特開 平２−65399（ＪＰ，Ａ) 特開 昭63−287298（ＪＰ，Ａ) 特開 昭63−246098（ＪＰ，Ａ) 特開 昭63−38399（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) H04R 7/02 C08L 5/08 D21H 13/30 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-5-183984 (JP, A) JP-A-4-70099 (JP, A) JP-A-3-232400 (JP, A) JP-A-3-232 229600 (JP, A) JP-A-4-213300 (JP, A) JP-A-2-65399 (JP, A) JP-A-63-287298 (JP, A) JP-A-63-246098 (JP, A) JP-A-63-38399 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) H04R 7/02 C08L 5/08 D21H 13/30
Claims (3)
化し、キトサン層を形成した繊維を単独で抄造、あるい
は異なる材料と混抄し、所定の形状に成形したスピーカ
用振動板。1. A speaker diaphragm formed by deacetylating the surface of a fiber composed of chitin and forming a fiber having a chitosan layer by itself or by mixing with a different material to form a predetermined shape.
繊維を用いた請求項１に記載のスピーカ用振動板。2. The speaker diaphragm according to claim 1, wherein the fiber to be mixed is a plant fiber such as pulp.
する合成樹脂のモノマーあるいはオリゴマーの水溶液も
しくはエマルジョンを用いた請求項１記載のスピーカ用
振動板。3. The diaphragm for a speaker according to claim 1, wherein an aqueous solution or emulsion of a monomer or oligomer of a synthetic resin having an epoxy group in a molecule is used as the binder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04316835A JP3109296B2 (en) | 1992-11-26 | 1992-11-26 | Speaker diaphragm |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04316835A JP3109296B2 (en) | 1992-11-26 | 1992-11-26 | Speaker diaphragm |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH06165288A JPH06165288A (en) | 1994-06-10 |
| JP3109296B2 true JP3109296B2 (en) | 2000-11-13 |
Family
ID=18081447
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP04316835A Expired - Fee Related JP3109296B2 (en) | 1992-11-26 | 1992-11-26 | Speaker diaphragm |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3109296B2 (en) |
-
1992
- 1992-11-26 JP JP04316835A patent/JP3109296B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH06165288A (en) | 1994-06-10 |
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| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |