JPS5911962B2 - Acoustic components and their manufacturing method - Google Patents
Acoustic components and their manufacturing methodInfo
- Publication number
- JPS5911962B2 JPS5911962B2 JP10558675A JP10558675A JPS5911962B2 JP S5911962 B2 JPS5911962 B2 JP S5911962B2 JP 10558675 A JP10558675 A JP 10558675A JP 10558675 A JP10558675 A JP 10558675A JP S5911962 B2 JPS5911962 B2 JP S5911962B2
- Authority
- JP
- Japan
- Prior art keywords
- deposited film
- specific gravity
- aluminum
- film
- base material
- 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
Links
- 238000004519 manufacturing process Methods 0.000 title claims description 6
- 229910052782 aluminium Inorganic materials 0.000 claims description 36
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 36
- 230000005484 gravity Effects 0.000 claims description 28
- 239000000463 material Substances 0.000 claims description 26
- 238000007740 vapor deposition Methods 0.000 claims description 7
- 238000007743 anodising Methods 0.000 claims description 3
- 238000000034 method Methods 0.000 description 9
- 238000011282 treatment Methods 0.000 description 7
- 238000000151 deposition Methods 0.000 description 4
- 230000008021 deposition Effects 0.000 description 4
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- 238000001704 evaporation Methods 0.000 description 3
- 230000008020 evaporation Effects 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 239000010936 titanium Substances 0.000 description 3
- 238000001771 vacuum deposition Methods 0.000 description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 2
- 229910052790 beryllium Inorganic materials 0.000 description 2
- ATBAMAFKBVZNFJ-UHFFFAOYSA-N beryllium atom Chemical compound [Be] ATBAMAFKBVZNFJ-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229910052719 titanium Inorganic materials 0.000 description 2
- 238000007738 vacuum evaporation Methods 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 238000002048 anodisation reaction Methods 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 239000002861 polymer material Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
- 238000001291 vacuum drying Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Laminated Bodies (AREA)
- Diaphragms For Electromechanical Transducers (AREA)
Description
【発明の詳細な説明】
本発明は音響部品及びその製造方法に係り、軽量でヤン
グ率が高く、しかも固体中の音の伝搬速度（以下本明細
書中ではこのことを音速という）が高く（速く）て低比
重の音響部品及びその製造方法を提供することを目的と
する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an acoustic component and a method for manufacturing the same, which is lightweight, has a high Young's modulus, and has a high propagation speed of sound in a solid (hereinafter referred to as sound speed). The object of the present invention is to provide a low specific gravity acoustic component and a method for manufacturing the same.
一般に、ピックアップ用カンチレバーあるいはスピーカ
用振動板等の音響部品には、高い音速で小なる比重を有
する材料を用いることが、その性能向上につながるとい
うことは周知の通りである。Generally, it is well known that using a material having a high sound velocity and a small specific gravity for acoustic components such as a pickup cantilever or a speaker diaphragm leads to improved performance.
し力化て、従来はアルミニウム合金あるいはチタンなど
の金属をそのまま成型していたため、音響部品としての
性能は形状寸法により限られていた。また一般に音響部
品に用いられるベリリウム（Ｂｅ）などの高い音速で音
を伝搬する、いわゆ１０る高音速材料は、加工が難しく
、そのため、テーパ形のピックアップ用カンチレバーパ
イプあるいは特に高音用スピーカのドーム形の振動板を
作る場合には、真空蒸着法を用いた成型法が最近用いら
れている。Conventionally, metals such as aluminum alloy or titanium were molded as they were, and their performance as acoustic components was limited by their shape and dimensions. In addition, so-called high-sonic materials such as beryllium (Be), which are commonly used in acoustic components and which propagate sound at high speeds, are difficult to process, so they are used in tapered cantilever pipes for pickups or domes especially for high-frequency speakers. When making a shaped diaphragm, a molding method using a vacuum evaporation method has recently been used.
この真空蒸着法は、特に小型の部品１５に対して量産性
に富み、またある程度表面形状が複雑であつても成型可
能であるから、特に上記のカンチレバーあるいは振動板
に対して好適であるが、実用的な肉厚（厚さ）を真空蒸
着法によつて得るためには、高い蒸着速度が要求される
。この高い蒸着速度を得ることができる真空蒸着材とし
ては、アルミニウム（Ａｌ）が古くから知られており、
蒸着速度などを制御することにより、蒸着膜はバルクの
アルミニウムに近い性質の緻密なものから、比重の小な
る多孔性のものまで比較的自２５由に得られる。また、
このアルミニウムの蒸着膜を陽極酸化することによつて
、予め成型された音響部品の基材面上に容易に酸化膜を
形成することができる。然るに、緻密でヤング率の大な
る上記酸化膜の３０厚さを大とすることは、陽極酸化時
の印加電圧の制限等種々の原因により、一般に困難であ
り、またこのため、通常音響部品に用いられるような数
１０μｍ程度の厚さのアルミニウムの音速を高め、かつ
比重を小とすることは極めて困難であつた。This vacuum evaporation method is especially suitable for the above-mentioned cantilever or diaphragm because it is particularly suitable for mass production of small parts 15 and can be molded even if the surface shape is complex to some extent. In order to obtain a practical thickness by vacuum deposition, a high deposition rate is required. Aluminum (Al) has long been known as a vacuum evaporation material that can achieve this high evaporation rate.
By controlling the deposition rate, etc., the deposited film can be relatively freely obtained, ranging from a dense film with properties similar to that of bulk aluminum to a porous film with a low specific gravity. Also,
By anodizing this vapor-deposited aluminum film, an oxide film can be easily formed on the base material surface of the pre-molded acoustic component. However, it is generally difficult to increase the thickness of the above-mentioned oxide film, which is dense and has a large Young's modulus, due to various reasons such as limitations on the applied voltage during anodic oxidation. It has been extremely difficult to increase the sound velocity and reduce the specific gravity of aluminum, which has a thickness of approximately several tens of micrometers.
３５また、このような真空蒸着法あるいはスパッタリン
グなどの手段により、成型物表面上にコートされるベリ
リウム等の高音速材料は、一般に高価である等の欠点が
あつた。35 Furthermore, high sonic velocity materials such as beryllium, which are coated on the surface of molded products by means such as vacuum evaporation or sputtering, generally have drawbacks such as being expensive.
本発明は上記諸欠点を除去するものであり、以下図面と
共にその各実施例につき説明する。The present invention is intended to eliminate the above-mentioned drawbacks, and each embodiment thereof will be described below with reference to the drawings.
第１図は本発明により表面処理を施された音響部品の第
１実施例の縦断側面図を示す。同図中、１はアルミニウ
ム若しくは高分子材料などの予め成型されている音響部
品用基材で、この基材１の表面上に所定値以下の比重の
多孔性のアルミニウム蒸着膜２が真空蒸着される。ここ
で、上記アルミニウム蒸着膜２は例えば被蒸着材の温度
６０℃、蒸着速度２０μｍ／騙では比重が２．０のもの
が得られ、また更に蒸着速度を大にすることによつて比
重が２．０以下の軽いものも得られる。本発明はこのア
ルミニウム蒸着膜２に陽極酸化を施すことにより、音速
を急激に増加せしめるものであり、この音速の増加は厚
さ１００Ｉｔｍ程度までは被処理物である蒸着膜２の厚
さに依存しないことが確認された。なお、多孔性のアル
ミニウム蒸着膜２の比重は、比重の異なる蒸着膜につい
て各種同様の処理を施した結果、比重が２．４を超える
場合には、陽極酸化による音速増加の効果が小となり、
このときの音速が６２００ｍ／ｓ程度となる。従つて、
アルミニウム蒸着膜２の比重を２．４以下とすることに
より、大なる音速で比重が小で、しかも陽極酸化を施さ
れた蒸着膜の厚さを従来にくらべかなり大にできる。例
えば、蒸着速度２０μｍ／Ｍｍで比重２．０１音ｌ速４
０００ｍ／ｓ１厚さ４０１ｔｍのアルミニウム蒸着膜を
予め成型されている音響部品基材１上に真空蒸着して形
成した後、この蒸着膜を５％の蓚酸水溶液中において印
加電圧３０で３時間陽極酸化し、その後水洗、真空乾燥
して得られたものは、比重が２．０、音速は７５００ｍ
／ｓとなつた。FIG. 1 shows a longitudinal sectional side view of a first embodiment of an acoustic component surface-treated according to the present invention. In the figure, reference numeral 1 denotes a pre-formed base material for acoustic components such as aluminum or polymer material, and a porous aluminum deposited film 2 having a specific gravity of less than a predetermined value is vacuum deposited on the surface of this base material 1. Ru. Here, for example, the aluminum vapor-deposited film 2 can have a specific gravity of 2.0 when the temperature of the material to be vaporized is 60° C. and the vapor deposition rate is 20 μm/m, and when the vapor deposition rate is further increased, the specific gravity is 2.0. Light weights of less than .0 can also be obtained. The present invention rapidly increases the speed of sound by anodizing the aluminum vapor deposited film 2, and the increase in the sound speed depends on the thickness of the vapor deposited film 2, which is the object to be treated, up to a thickness of about 100 Itm. It was confirmed that it does not. In addition, the specific gravity of the porous aluminum vapor deposited film 2 was determined by applying various similar treatments to vapor deposited films with different specific gravity, and when the specific gravity exceeds 2.4, the effect of increasing the sound velocity due to anodic oxidation is small.
The speed of sound at this time is approximately 6200 m/s. Therefore,
By setting the specific gravity of the aluminum vapor deposited film 2 to 2.4 or less, the specific gravity is small at a high sound velocity, and the thickness of the anodized vapor deposited film can be made considerably larger than that of the conventional method. For example, at a deposition rate of 20 μm/Mm, a specific gravity of 2.01 and a sound l velocity of 4
After forming an aluminum vapor deposition film with a thickness of 000 m/s1 and a thickness of 401 tm on the pre-formed acoustic component base material 1 by vacuum vapor deposition, this vapor deposition film was anodized in a 5% oxalic acid aqueous solution at an applied voltage of 30 hours for 3 hours. The product obtained by washing with water and vacuum drying has a specific gravity of 2.0 and a sound velocity of 7500 m.
/s became.
これを従来の音響部品に用いられているアルミニウム、
チタン（Ｔｉ）と比較したのが下記の表である。また、
この処理方法による蒸着膜の比重と音速との関係は、第
２図に示す如くになり、蒸着速度を例えば２０Ｉｔｍ／
Ｍｍより遅くする程音速は７５００ｍ／ｓよりも小とな
る。This is compared to the aluminum used in conventional acoustic components.
The table below shows a comparison with titanium (Ti). Also,
The relationship between the specific gravity of the vapor deposited film and the sound velocity by this treatment method is as shown in Figure 2, and the vapor deposition rate is set to 20 Itm/
The sound speed becomes smaller than 7500 m/s as the speed becomes slower than Mm.
但し、蒸着膜の比重は前述したように蒸着速度が遅くな
るほど大になるが、上記の処理前後では殆ど変化しない
。なお、本発明のように多孔性のアルミニウム蒸着膜を
形成せず、単に厚さ４０μｍのアルミニウム成型物を上
記と同様の方法で陽極酸化したものは箔片の１Ｃ！！ｌ
当りの比重、音速ともに殆ど変化しなかつた。ところで
、上記の処理方法によつて得られるアルミニウム蒸着膜
２は基材１と共に一体的に使用されるが、基材１より剥
離してそのまま使用しても良い。However, as described above, the specific gravity of the deposited film increases as the deposition rate decreases, but it hardly changes before and after the above treatment. Note that, unlike the present invention, when a porous aluminum vapor-deposited film is not formed and a 40 μm thick aluminum molded product is simply anodized in the same manner as above, the foil piece is 1C! ! l
Both the specific gravity and the speed of sound at impact remained almost unchanged. Incidentally, although the aluminum vapor deposited film 2 obtained by the above-mentioned treatment method is used integrally with the base material 1, it may be peeled off from the base material 1 and used as it is.
この剥離して用いる場合、基材１がアルミニウムである
ときには、基材１の表面上に蒸着された蒸着膜の剥離を
行なうことなしに陽極酸化できるため、工程を簡略化で
きると共に、蒸着膜のみの場合の脆さを補うことができ
るので極めて有利である。第３図は本発明により表面処
理を施された音響部品の第２実施例の縦断側面図を示す
。When used after peeling off, when the base material 1 is aluminum, anodization can be performed without peeling off the vapor deposited film deposited on the surface of the base material 1, which simplifies the process and allows only the vapor deposited film to be used on the surface of the base material 1. This is extremely advantageous because it can compensate for the fragility of the case. FIG. 3 shows a longitudinal sectional side view of a second embodiment of an acoustic component surface-treated according to the present invention.
同図中、第１図と同一部分には同一符号を付し、その説
明を省略する。本実施例は基材１が例えば高分子材料な
どの場合（アルミニウムでも勿論よい）、その表面に緻
密なアルミニウム蒸着膜３を形成し、その後上記多孔性
蒸着膜２を形成して上記処理を行なうことにより、密着
性を保つたまま基材１の補強を行なうようにしたもので
ある。すなわち、緻密なアルミニウム蒸着膜３は、成型
されている基材１への密着性を保ち、かつ酸化処理を施
した多孔性蒸着膜２の剥離を防ぐものであり、この蒸着
膜３が多孔性であると蒸着膜３と基材１とが剥離し易く
なるため、可能な限り緻密で膜全体にわたつて酸化され
ない程度のものが良い。このためには、蒸着膜３の比重
としては、上記の音速増加の効果が小となる点が１つの
目安であるが、剥離試験によると比重が２．５以上の場
合、蒸着膜２，３間の接着は良好である。また、蒸着膜
３の厚さを適当に選定することによつて、蒸着膜３は全
体にわたつて酸化されないため基材１と蒸着膜３との間
で、上記処理前の密着性を保つことができる。上述の如
く、本発明になる音響部品及びその製造方法によれば、
少なくとも多孔性でかつ約２．４以下の比重を有する陽
極酸化されたアルミニウム蒸着膜が所定形状に形成され
てなるため、上記アルミニウム蒸着膜の厚さを大に形成
できるのでヤング率を大にでき、しかも比重が小で音速
が大なる音響部品を得ることができ、従つてピツクアツ
プのカンチレバ一あるいは高音用スピーカの振動板とし
て用いることによりこれらの再生周波数帯域を拡大（過
渡特性が良く、特に高域がのびる）でき、従来にくらべ
安価で量産性に富み、また上記アルミニウム蒸着膜は上
記約２．４よりも大なる値の比重でかつ全体が少なくと
も陽極酸化されない程度の厚さを有するアルミニウム蒸
着膜上に形成したため、上記２つのアルミニウム蒸着膜
間の接着を良好にでき、しかも上記陽極酸化されない程
度の厚さを有するアルミニウム蒸着膜が予め所定形状に
成型された音響部品用基材表面上に形成される場合は、
この基材と上記約２，４よりも大なる値の比重のアルミ
ニウム蒸着膜との間の密着性を保つたまま上記基材の補
強ができ、更に上記音響部品用基材をアルミニウムとし
、このアルミニウム及び上記約２．４以下の比重を有す
るアルミニウム蒸着膜を陽極酸化するようにしたため、
このアルミニウム蒸着膜を剥離することなく陽極酸化で
き、従つて工程が簡略化でき、上記蒸着膜のみを陽極酸
化する場合の脆さをなくすことができる等の数々の特長
を有するものである。In the figure, the same parts as in FIG. 1 are designated by the same reference numerals, and their explanations will be omitted. In this example, when the base material 1 is made of, for example, a polymeric material (of course, aluminum may also be used), a dense aluminum vapor deposited film 3 is formed on its surface, and then the porous vapor deposited film 2 is formed and the above treatment is performed. By doing so, the base material 1 is reinforced while maintaining adhesion. That is, the dense aluminum vapor deposited film 3 maintains adhesion to the base material 1 being molded and prevents the peeling of the porous vapor deposited film 2 that has been subjected to oxidation treatment. If this is the case, the deposited film 3 and the base material 1 will easily separate, so it is preferable that the film be as dense as possible and not oxidized over the entire film. For this purpose, one guideline for the specific gravity of the vapor deposited film 3 is that the effect of increasing the sound velocity described above is small; however, according to a peel test, if the specific gravity is 2.5 or more, the vapor deposited film 2, 3 The adhesion between them is good. In addition, by appropriately selecting the thickness of the vapor deposited film 3, the entire vapor deposited film 3 is not oxidized, so that the adhesion between the base material 1 and the vapor deposited film 3 before the above treatment can be maintained. I can do it. As described above, according to the acoustic component and the manufacturing method thereof according to the present invention,
Since an anodized aluminum evaporation film that is at least porous and has a specific gravity of about 2.4 or less is formed into a predetermined shape, the aluminum evaporation film can be formed to have a large thickness, so that the Young's modulus can be increased. Moreover, it is possible to obtain an acoustic component with a small specific gravity and a high sound velocity. Therefore, by using it as a pick-up cantilever or a diaphragm for a high-frequency speaker, the reproduction frequency band can be expanded (with good transient characteristics, especially for high-frequency speakers). The aluminum vapor-deposited film has a specific gravity greater than about 2.4 and is thick enough to prevent the entire film from being anodized. Since it is formed on the film, the adhesion between the two aluminum vapor deposited films can be improved, and the aluminum vapor deposited film having a thickness that is not anodic oxidized is formed on the surface of the base material for acoustic components that has been previously formed into a predetermined shape. If formed,
The base material can be reinforced while maintaining the adhesion between the base material and the aluminum vapor-deposited film having a specific gravity greater than about 2.4. Since aluminum and the aluminum vapor deposited film having a specific gravity of about 2.4 or less are anodized,
This method has a number of advantages, such as being able to anodize the aluminum vapor deposited film without peeling it off, simplifying the process, and eliminating the brittleness that would otherwise occur when only the vapor deposited film is anodized.
第１図は本発明になる音響部品の第１実施例の縦断側面
図、第２図は第１図の蒸着膜の比重と音速との関係を示
す図、第３図は本発明になる音響部品の第２実施例の縦
断側面図である。
１・・・・・・音響部品用基材、２・・・・・・多孔性
のアルミニウム蒸着膜、３・・・・・・緻密なアルミニ
ウム蒸着膜。FIG. 1 is a vertical side view of the first embodiment of the acoustic component according to the present invention, FIG. 2 is a diagram showing the relationship between the specific gravity of the vapor deposited film in FIG. 1 and the sound velocity, and FIG. 3 is the acoustic component according to the present invention. FIG. 6 is a longitudinal side view of a second embodiment of the component; 1... Base material for acoustic components, 2... Porous aluminum vapor deposited film, 3... Dense aluminum vapor deposited film.
Claims (1)
する陽極酸化されたアルミニウム蒸着膜が所定形状に形
成されてなることを特徴とする音響部品。 ２ 上記アルミニウム蒸着膜は、上記約２．４よりも大
なる値の比重でかつ全体が少なくとも陽極酸化されない
程度の厚さを有するアルミニウム蒸着膜上に形成されて
なることを特徴とする特許請求の範囲第１項記載の音響
部品。 ３ アルミニウムよりなる音響部品用基材上に上記約２
．４以下の比重を有する多孔性のアルミニウム蒸着膜を
形成する蒸着工程と、該基材及びアルミニウム蒸着膜を
陽極酸化する工程とよりなることを特徴とする特許請求
の範囲第１項記載の音響部品を製造する方法。Claims: 1. An acoustic component comprising at least an anodized aluminum vapor deposited film that is porous and has a specific gravity of about 2.4 or less and is formed into a predetermined shape. 2. The aluminum vapor-deposited film is formed on an aluminum vapor-deposited film having a specific gravity greater than the above-mentioned approximately 2.4 and a thickness to the extent that the entire film is at least not anodized. Acoustic components as described in scope 1. 3 Approximately 2 of the above are placed on the base material for acoustic components made of aluminum.
．． The acoustic component according to claim 1, comprising a vapor deposition step of forming a porous aluminum vapor deposited film having a specific gravity of 4 or less, and an anodizing step of the base material and the aluminum vapor deposited film. How to manufacture.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10558675A JPS5911962B2 (en) | 1975-09-02 | 1975-09-02 | Acoustic components and their manufacturing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10558675A JPS5911962B2 (en) | 1975-09-02 | 1975-09-02 | Acoustic components and their manufacturing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5229703A JPS5229703A (en) | 1977-03-05 |
| JPS5911962B2 true JPS5911962B2 (en) | 1984-03-19 |
Family
ID=14411592
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10558675A Expired JPS5911962B2 (en) | 1975-09-02 | 1975-09-02 | Acoustic components and their manufacturing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5911962B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS553549U (en) * | 1978-06-20 | 1980-01-10 |
-
1975
- 1975-09-02 JP JP10558675A patent/JPS5911962B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5229703A (en) | 1977-03-05 |
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