JPH0116155Y2 - - Google Patents
Info
- Publication number
- JPH0116155Y2 JPH0116155Y2 JP8773583U JP8773583U JPH0116155Y2 JP H0116155 Y2 JPH0116155 Y2 JP H0116155Y2 JP 8773583 U JP8773583 U JP 8773583U JP 8773583 U JP8773583 U JP 8773583U JP H0116155 Y2 JPH0116155 Y2 JP H0116155Y2
- Authority
- JP
- Japan
- Prior art keywords
- permanent magnet
- case
- cavity
- diaphragm
- electromagnet
- 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
- 230000002093 peripheral effect Effects 0.000 claims description 6
- 230000003993 interaction Effects 0.000 claims description 4
- BGPVFRJUHWVFKM-UHFFFAOYSA-N N1=C2C=CC=CC2=[N+]([O-])C1(CC1)CCC21N=C1C=CC=CC1=[N+]2[O-] Chemical compound N1=C2C=CC=CC2=[N+]([O-])C1(CC1)CCC21N=C1C=CC=CC1=[N+]2[O-] BGPVFRJUHWVFKM-UHFFFAOYSA-N 0.000 description 23
- 239000000853 adhesive Substances 0.000 description 14
- 230000001070 adhesive effect Effects 0.000 description 14
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000004907 flux Effects 0.000 description 2
- 238000005192 partition Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000002991 molded plastic Substances 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000005476 soldering Methods 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Landscapes
- Electrostatic, Electromagnetic, Magneto- Strictive, And Variable-Resistance Transducers (AREA)
Description
【考案の詳細な説明】
産業上の利用分野
本考案は、例えば各種の時計、カメラ、電子レ
ンジ、ポータブル．ビデオ．テープ．レコーダま
たはポケツトベル等において、報音用として使用
される音響変換器に関する。[Detailed Description of the Invention] Industrial Fields of Use This invention can be applied to various types of watches, cameras, microwave ovens, and portable devices, for example. video. tape. This invention relates to an acoustic transducer used for sound reporting in recorders, pagers, etc.
従来技術とその問題点
この種の音響変換器としては、圧電型等のもの
も知られているが、最近、2KHz前後の低周波領
域に共振点を持つ電磁型のものが注目されてい
る。この電磁型音響変換器は、振動板を直流的な
磁界と、交流的な磁界との磁気的相互作用により
励振して、振動音を得るものである。この場合、
音圧レベルを向上させる手段として、音響変換部
を収納するケースの内部に形成される空洞の空洞
共振系を利用して、音圧レベルを向上させる構造
のものが提案されている。Prior Art and Its Problems Although piezoelectric type acoustic transducers and the like are known as this type of acoustic transducer, recently, electromagnetic type acoustic transducers that have a resonance point in a low frequency region of around 2 KHz have been attracting attention. This electromagnetic acoustic transducer excites a diaphragm through magnetic interaction between a direct current magnetic field and an alternating current magnetic field to obtain vibrating sound. in this case,
As a means for improving the sound pressure level, a structure has been proposed in which the sound pressure level is improved by utilizing a cavity resonance system formed inside a case that houses an acoustic converter.
第１図及び第２図はこの種の前記電磁型音響変
換器の従来例における断面図である。まず第１図
の従来例では、コイル２を巻装した鉄心３を有す
るヨーク４の上面に、前記コイル２及び鉄心３か
ら成る電磁石を包囲する如く、フエライトマグネ
ツトもしくはプラスチツク成形マグネツト等の円
筒状の永久磁石５を配置すると共に、該永久磁石
５の上端面に円板状の振動板６を装架することに
より、音響変換部を構成し、この音響変換部を非
磁性金属材料または合成樹脂等より成る円筒状ケ
ース１の底部開口部に装着した構造となつてい
る。 FIGS. 1 and 2 are cross-sectional views of conventional examples of this type of electromagnetic acoustic transducer. First, in the conventional example shown in FIG. 1, a cylindrical magnet such as a ferrite magnet or a molded plastic magnet is placed on the upper surface of a yoke 4 having an iron core 3 around which a coil 2 is wound, so as to surround an electromagnet consisting of the coil 2 and iron core 3. An acoustic transducer is constructed by arranging a permanent magnet 5 and mounting a disc-shaped diaphragm 6 on the upper end surface of the permanent magnet 5. It has a structure in which it is attached to the bottom opening of a cylindrical case 1 consisting of a cylindrical case 1 and the like.
ケース１の内部は、下端縁を開口させた仕切板
７によつて二つの空室８及び９に区画し、一方の
空室８内に音響変換部を組込み、該音響変換部を
構成する永久磁石５の下端面の一部に通孔状また
は溝状の切欠１０を設け、該切欠１０を通して、
振動板６の背面側の空洞１１を空室９に連通させ
た構造となつている。空室９の上面側には放音孔
１２を穿設してあり、振動板６の背面側の空洞共
振を、永久磁石５に設けた切欠１０及び空室９を
通して、空室９の上方に設けた放音孔１２に導く
ようになつている。 The inside of the case 1 is divided into two chambers 8 and 9 by a partition plate 7 with an open lower edge, and an acoustic converter is built into one of the chambers 8, and a permanent A hole-shaped or groove-shaped cutout 10 is provided in a part of the lower end surface of the magnet 5, and the cutout 10 is inserted through the cutout 10.
It has a structure in which a cavity 11 on the back side of the diaphragm 6 is communicated with a cavity 9. A sound emitting hole 12 is bored on the upper side of the cavity 9, and the cavity resonance on the back side of the diaphragm 6 is transmitted above the cavity 9 through the notch 10 provided in the permanent magnet 5 and the cavity 9. The sound is guided to a sound emitting hole 12 provided.
また、振動板６の上方の前記ケース１の上面部
には放音孔１３を設けてあり、該放音孔１３によ
り、振動板６の前面の空洞１４の空洞共振系によ
る共振作用を利用して、音圧レベルを向上させる
ようにしてある。 Further, a sound emitting hole 13 is provided on the upper surface of the case 1 above the diaphragm 6, and the sound emitting hole 13 makes use of the resonance effect of the cavity resonance system of the cavity 14 on the front surface of the diaphragm 6. This is designed to improve the sound pressure level.
１５はヨーク４と共に前記ケース１の底部開口
部に装着される端子基板であり、前記コイル２の
コイル端末を導通接続させるピン状の端子１６，
１７を植設してある。 15 is a terminal board attached to the bottom opening of the case 1 together with the yoke 4, and a pin-shaped terminal 16 for electrically connecting the coil end of the coil 2;
17 have been planted.
この種の音響変換器は、振動板６の前面及び背
面側の空洞１１及び１４の空洞共振系による共振
作用を利用して、音圧レベルを向上させるもので
あるから、空洞１１及び１４を互いに遮断し、相
互干渉を阻止する必要がある。その手段として、
第１図の従来例では、永久磁石５とケース１との
間の適当な位置に接着剤１８を流し込み、この接
着剤１８によつて空洞１４を空室９から遮断して
いた。 This type of acoustic transducer uses the resonance effect of the cavity resonance system of the cavities 11 and 14 on the front and rear sides of the diaphragm 6 to improve the sound pressure level. It is necessary to block them and prevent mutual interference. As a means of doing so,
In the conventional example shown in FIG. 1, an adhesive 18 is poured into an appropriate position between the permanent magnet 5 and the case 1, and the cavity 14 is isolated from the cavity 9 by the adhesive 18.
しかしながら、永久磁石５の外周面とケース１
の内周面との間に接着剤１８を流し込む構造で
は、接着剤１８が永久磁石５の外周面とケース１
の内周面との間に形成される隙間を通つて、振動
板６の方向に流れ込み、振動板６がこの接着剤１
８によつて永久磁石５に接着されてしまい、特性
不良を招くことがあつた。また、組立作業が非常
に面倒で、量産性に欠ける等の難点もあつた。 However, the outer peripheral surface of the permanent magnet 5 and the case 1
In the structure in which the adhesive 18 is poured between the inner peripheral surface of the permanent magnet 5 and the outer peripheral surface of the permanent magnet 5, the adhesive 18 is poured between the outer peripheral surface of the permanent magnet 5 and the
The adhesive flows in the direction of the diaphragm 6 through the gap formed between the adhesive 1 and the inner peripheral surface of the diaphragm 6.
8, it was adhered to the permanent magnet 5, resulting in poor characteristics. Additionally, there were other drawbacks, such as the extremely troublesome assembly work and lack of mass production.
次に第２図の従来例では、接着剤を用いない
で、永久磁石５をケース１の内部に圧入して組立
てる構造となつている。この第２図の従来例にお
いては、第１図の従来例と異なつて、接着剤によ
る不具合を生じる余地はない。しかしながら、永
久磁石５をヨーク４の上に固着する構造を採つた
場合、両者４−５間に僅かでも組立位置ズレを生
じると、ヨーク４の外周がケース１の内径からは
み出してしまうため、組立が不可能になる。一
方、永久磁石５がヨーク４上に固定されていない
場合、つまり永久磁石５を自己の磁気的吸着力に
よつてヨーク４上に装着させた場合は、圧入作業
時に永久磁石５がヨーク４から浮き上がり、振動
特性に最も重要な空隙G1の寸法が変動し、周波
数特性、音圧及び音色が変動してしまうと言う難
点があつた。 Next, in the conventional example shown in FIG. 2, the permanent magnet 5 is press-fitted into the case 1 and assembled without using an adhesive. In the conventional example shown in FIG. 2, unlike the conventional example shown in FIG. 1, there is no possibility of problems caused by the adhesive. However, if a structure is adopted in which the permanent magnet 5 is fixed on the yoke 4, even a slight deviation in the assembly position between the two 4-5 will cause the outer periphery of the yoke 4 to protrude from the inner diameter of the case 1. becomes impossible. On the other hand, if the permanent magnet 5 is not fixed on the yoke 4, that is, if the permanent magnet 5 is mounted on the yoke 4 by its own magnetic attraction force, the permanent magnet 5 will be removed from the yoke 4 during press-fitting. There was a problem in that the dimensions of the air gap G1, which is most important for the lifting and vibration characteristics, fluctuated, resulting in fluctuations in frequency characteristics, sound pressure, and timbre.
本考案の目的
そこで本考案は上述する従来の欠点を除去し、
音響変換部をケース内部に組込む場合に、接着剤
による振動板の接着固定、永久磁石の浮上がり等
の不具合を生じる余地がなく、所定位置に簡単か
つ確実に位置決めでき、特性の安定した組立の簡
単な高信頼度の音響変換器を提供することを目的
とする。Purpose of the present invention Therefore, the present invention eliminates the above-mentioned conventional drawbacks,
When assembling the acoustic transducer inside the case, there is no possibility of problems such as fixation of the diaphragm with adhesive or floating of the permanent magnet, and the assembly can be easily and reliably positioned in a predetermined position, with stable characteristics. The purpose is to provide a simple and highly reliable acoustic transducer.
本考案の構成
上記目的を達成するため、本考案は、電磁石
と、該電磁石を包囲するように配置された永久磁
石と、前記電磁石の磁極に対して空隙を介して対
向し、前記電磁石及び前記永久磁石の磁気的相互
作用により励振される振動板とを備えて構成され
る音響変換部を、ケースの一端側からその内部に
嵌挿して構成される音響変換器において、前記ケ
ースは、前記音響変換部を収納する空室から区画
された別の空室を有し、該空室を前記振動板の背
面側の空洞共振系と連通させ、前記ケースの内周
面と前記永久磁石の端面とのそれぞれに、互いに
適合するテーパ面を設け、該テーパ面を互いに当
接させて前記２つの空室を区切つたことを特徴と
する。Structure of the Present Invention In order to achieve the above object, the present invention includes an electromagnet, a permanent magnet arranged to surround the electromagnet, and a permanent magnet that faces the magnetic pole of the electromagnet with an air gap between the electromagnet and the permanent magnet. An acoustic transducer configured by inserting an acoustic transducer including a diaphragm excited by magnetic interaction of permanent magnets into the interior of the case from one end side. It has a separate cavity separated from the cavity that houses the conversion section, communicates the cavity with a cavity resonance system on the back side of the diaphragm, and connects the inner circumferential surface of the case and the end face of the permanent magnet. Each of the chambers is provided with a tapered surface that fits with the other, and the tapered surfaces are brought into contact with each other to separate the two empty chambers.
実施例
第３図は本考案に係る音響変換器の正面断面図
である。図において、第１図及び第２図と同一の
参照符号は同一性ある構成部分を示している。図
示するように、本考案においては、音響変換部を
収納するケース１の内周面の適当な位置に、その
全周に亘つて、テーパ面１９を設ける一方、永久
磁石５の側端面の全周に亘つて、前記テーパ面１
９に適合するテーパ面２０を設け、該テーパ面１
９，２０が互いに密着して当接するように、永久
磁石５をケース１内に嵌挿してある。永久磁石５
は自己の磁気的吸着力により、ヨーク４上に装着
されている。Embodiment FIG. 3 is a front sectional view of an acoustic transducer according to the present invention. In the figures, the same reference numerals as in FIGS. 1 and 2 indicate the same components. As shown in the figure, in the present invention, a tapered surface 19 is provided at an appropriate position on the inner circumferential surface of the case 1 that houses the acoustic transducer, and a tapered surface 19 is provided along the entire circumference of the case 1. The tapered surface 1 over the circumference
A tapered surface 20 matching the shape of the tapered surface 1 is provided.
The permanent magnet 5 is inserted into the case 1 so that the magnets 9 and 20 are in close contact with each other. Permanent magnet 5
is mounted on the yoke 4 by its own magnetic attraction force.
このような構造であると、振動板６の前面に形
成される空洞共振系１４と、背面側に形成される
空洞共振系１１，９とを、接着剤を使用すること
なく、前記テーパ面１９−２０間の密着によつて
遮断することができる。従つて、接着剤によつて
振動板５が固着されると言つた不具合を生じる余
地がなく、特性の安定した音響変換器が得られ
る。また、ケース１と永久磁石５がテーパ面１９
−２０によりテーパ嵌合しているので、ケース１
側から永久磁石５の方向に押圧力が働き、永久磁
石５の浮上がりが阻止される。このため、振動板
６と磁極３との間の空隙が一定に保たれ、振動板
６の振動特性が安定する。更に前記テーパ嵌合に
より、永久磁石５に対して位置ズレ修正作用が働
くので、永久磁石５が組立工程において自動的に
所定位置にセツトされる。 With this structure, the cavity resonance system 14 formed on the front side of the diaphragm 6 and the cavity resonance systems 11 and 9 formed on the back side can be connected to the tapered surface 19 without using an adhesive. It can be blocked by close contact between -20 and 20. Therefore, there is no possibility of problems such as the diaphragm 5 being fixed by adhesive, and an acoustic transducer with stable characteristics can be obtained. In addition, the case 1 and the permanent magnet 5 are connected to the tapered surface 19.
Since the tapered fit is made by -20, case 1
A pressing force acts in the direction of the permanent magnet 5 from the side, and the permanent magnet 5 is prevented from floating. Therefore, the air gap between the diaphragm 6 and the magnetic pole 3 is kept constant, and the vibration characteristics of the diaphragm 6 are stabilized. Furthermore, since the tapered fitting acts to correct the positional deviation of the permanent magnet 5, the permanent magnet 5 is automatically set at a predetermined position during the assembly process.
更にこの実施例では、電磁石を構成するヨーク
４の一端側に、電磁音響変換部を収納する空室８
から、仕切板７によつて区画された空室９に達す
る切欠２１を設け、該切欠２１によつて、振動板
６の背面側の空洞１１と、空室９とを互いに連通
させた構造となつている。 Furthermore, in this embodiment, a vacant space 8 for housing an electromagnetic acoustic transducer is provided at one end side of the yoke 4 constituting the electromagnet.
, a notch 21 is provided that reaches the cavity 9 divided by the partition plate 7, and the cavity 11 on the back side of the diaphragm 6 and the cavity 9 are communicated with each other through the notch 21. It's summery.
このような構造であると、振動板６の背面側の
空洞１１と、空室９とを互いに連通させるに当つ
て、永久磁石５に対して何らの加工も施す必要が
ない。しかも、ヨーク４の切欠２１は、例えばプ
レス加工等の手段によつて、高精度で簡単に形成
することができる。このため、高精度で、特性の
安定した安価な音響変換器が得られる。また、回
路基板への実装時に半田付けフラツクスが侵入す
ることがないので、フラツクス侵入による特性劣
化等を生じることのない安定した特性の音響変換
器が得られる。 With this structure, there is no need to perform any processing on the permanent magnet 5 in order to make the cavity 11 on the back side of the diaphragm 6 and the cavity 9 communicate with each other. Moreover, the notch 21 of the yoke 4 can be easily formed with high precision by means such as press working. Therefore, an inexpensive acoustic transducer with high precision and stable characteristics can be obtained. Furthermore, since soldering flux does not enter during mounting on a circuit board, an acoustic transducer with stable characteristics that does not suffer from characteristic deterioration due to flux intrusion can be obtained.
本考案の効果
以上述べたように、本考案は、電磁石と、該電
磁石を包囲するように配置された永久磁石と、前
記電磁石の磁極に対して空隙を介して対向し、前
記電磁石及び前記永久磁石の磁気的相互作用によ
り励振される振動板とを備えて構成される音響変
換部を、ケースの一端側からその内部に嵌挿して
構成される音響変換器において、前記ケースは、
前記音響変換部を収納する空室から区画された別
の空室を有し、該空室を前記振動板の背面側の空
洞共振系と連通させ、前記ケースの内周面と前記
永久磁石の端面とのそれぞれに、互いに適合する
テーパ面を設け、該テーパ面を互いに当接させて
前記２つの空室を区切つたことを特徴とするか
ら、音響変換部をケース内部に組込む場合に、接
着剤による振動板の接着固定或いは永久磁石の浮
上がり等の不具合を生じる余地がなく、所定位置
に簡単かつ確実に位置決めでき、特性の安定した
組立の簡単な高信頼度の音響変換器を提供するこ
とができる。Effects of the present invention As described above, the present invention includes an electromagnet, a permanent magnet arranged to surround the electromagnet, and a permanent magnet that faces the magnetic poles of the electromagnet with an air gap between the electromagnet and the permanent magnet. In an acoustic transducer configured by inserting an acoustic transducer including a diaphragm excited by magnetic interaction of magnets into the interior of the case from one end side, the case includes:
It has another cavity separated from the cavity housing the acoustic converter, and communicates the cavity with the cavity resonance system on the back side of the diaphragm, and connects the inner circumferential surface of the case and the permanent magnet. A tapered surface that fits each other is provided on each of the end surfaces, and the two empty chambers are separated by making the tapered surfaces come into contact with each other. Therefore, when the acoustic converting section is assembled inside the case, there is no need to use adhesive. To provide a highly reliable acoustic transducer that can be easily and reliably positioned at a predetermined position, has stable characteristics, is easy to assemble, and has no possibility of problems such as adhesive fixation of a diaphragm with adhesive or floating of a permanent magnet. be able to.
第１図は従来の音響変換器の正面断面図、第２
図は同じく別の従来例における正面断面図、第３
図は本考案に係る音響変換器の正面断面図であ
る。
１…ケース、２…コイル、３…鉄心、４…ヨー
ク、５…永久磁石、６…振動板、１９…テーパ
面、２０…テーパ面。
Figure 1 is a front sectional view of a conventional acoustic transducer;
The figure is also a front sectional view of another conventional example.
The figure is a front sectional view of the acoustic transducer according to the present invention. DESCRIPTION OF SYMBOLS 1... Case, 2... Coil, 3... Iron core, 4... Yoke, 5... Permanent magnet, 6... Vibration plate, 19... Tapered surface, 20... Tapered surface.
Claims (1)
た永久磁石と、前記電磁石の磁極に対して空隙を
介して対向し、前記電磁石及び前記永久磁石の磁
気的相互作用により励振される振動板とを備えて
構成される音響変換部を、ケースの一端側からそ
の内部に嵌挿して構成される音響変換器におい
て、前記ケースは、前記音響変換部を収納する空
室から区画された別の空室を有し、該空室を前記
振動板の背面側の空洞共振系と連通させ、前記ケ
ースの内周面と前記永久磁石の端面とのそれぞれ
に、互いに適合するテーパ面を設け、該テーパ面
を互いに当接させて前記２つの空室を区切つたこ
とを特徴とする音響変換器。 An electromagnet, a permanent magnet arranged to surround the electromagnet, and a diaphragm that faces magnetic poles of the electromagnet with an air gap and is excited by magnetic interaction between the electromagnet and the permanent magnet. In the acoustic transducer configured by inserting an acoustic converting section into the interior of the case from one end side, the case has a separate empty room partitioned from the empty room that accommodates the acoustic converting section. , the cavity is communicated with the cavity resonance system on the back side of the diaphragm, and the inner peripheral surface of the case and the end surface of the permanent magnet are each provided with a tapered surface that matches each other, and the tapered surface An acoustic transducer characterized in that the two empty chambers are partitioned by making the two chambers come into contact with each other.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8773583U JPS59192199U (en) | 1983-06-08 | 1983-06-08 | acoustic transducer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8773583U JPS59192199U (en) | 1983-06-08 | 1983-06-08 | acoustic transducer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59192199U JPS59192199U (en) | 1984-12-20 |
| JPH0116155Y2 true JPH0116155Y2 (en) | 1989-05-12 |
Family
ID=30217651
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8773583U Granted JPS59192199U (en) | 1983-06-08 | 1983-06-08 | acoustic transducer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59192199U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6907955B2 (en) | 2002-10-28 | 2005-06-21 | Star Micronics Co., Ltd. | Electromagnetic electroacoustic transducer |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2781126B2 (en) * | 1993-05-27 | 1998-07-30 | スター精密株式会社 | Electroacoustic transducer |
-
1983
- 1983-06-08 JP JP8773583U patent/JPS59192199U/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6907955B2 (en) | 2002-10-28 | 2005-06-21 | Star Micronics Co., Ltd. | Electromagnetic electroacoustic transducer |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59192199U (en) | 1984-12-20 |
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