JP2008244710A - Electroacoustic transducer - Google Patents

Electroacoustic transducer Download PDF

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Publication number
JP2008244710A
JP2008244710A JP2007080775A JP2007080775A JP2008244710A JP 2008244710 A JP2008244710 A JP 2008244710A JP 2007080775 A JP2007080775 A JP 2007080775A JP 2007080775 A JP2007080775 A JP 2007080775A JP 2008244710 A JP2008244710 A JP 2008244710A
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Prior art keywords
magnetic circuit
yoke
stopper member
electroacoustic transducer
outer peripheral
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Japanese (ja)
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Toshio Itakura
敏雄 板倉
Masahito Furuya
正仁 古屋
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Citizen Electronics Co Ltd
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Citizen Electronics Co Ltd
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Priority to JP2007080775A priority Critical patent/JP2008244710A/en
Publication of JP2008244710A publication Critical patent/JP2008244710A/en
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Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that work is difficult for forming a flange part by extending the outer peripheral part of a yoke. <P>SOLUTION: The electroacoustic transducer comprises a magnetic circuit part 1 configured by laminating a magnet 3 and a top plate 4 inside the yoke 2, a voice coil 5 arranged inside a gap g between the inner peripheral part of the sidewall of the yoke 2 of the magnetic circuit part 1 and the outer peripheral part of the top plate 4, a diaphragm 7 for holding the voice coil 5 on the outer part of the magnetic circuit part 1, and a suspension 8 held by a case 6 for holding the magnetic circuit part 1, and a stopper member 12 to which bending work is executed is disposed to the magnetic circuit part 1. The stopper member 12 is composed of a metal or resin member and is clamped between the flange part lower surface of the yoke 2 and a ring-like weight 11 fixed to the outer peripheral part of the yoke 2. The stopper member 12 absorbs an external impact and prevents the deformation and breakage of components. Since the stopper member 12 is a separate component, it is easily worked. For that, additional mass is added and vibration characteristics are stabilized. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

本発明は、携帯電話やPDAなどの移動通信機器に組み込まれ、パネルや電話機の筐体等を振動させることにより、着信を知らせる電気音響変換器に関する。   The present invention relates to an electroacoustic transducer that is incorporated in a mobile communication device such as a mobile phone or a PDA, and notifies an incoming call by vibrating a panel, a casing of a telephone, or the like.

従来、携帯電話やPDAなどの移動通信機器には、使用者に着信を知らせるのに、ブザー音やメロディ音を発生したり、音を出さずに機器の筐体を振動させるように切り替えて使用するように構成されている。そのために、小型スピーカに類する音響発生用のスピーカと、偏心重りを小型モータで回転させて振動を発生する振動体を合わせて内蔵する構造が取られてきた。しかし、このようにスピーカと振動体との両方を組込むことは機器の小型化や低価格化の上で不利であった。そこで、近年1個のもので音響と振動の両方を発生させる磁気駆動型アクチュエータである多機能振動アクチュエータ(振動体)が用いられるようになっている。このような、多機能振動アクチュエータは外力によって衝撃を受けた場合、変形したり破損により共振特性が劣化したり、内部の部品同士が接触するなどして、動作中に擦過音を生じたりすることがある。これに対処した多機能型発音体が開示されている。(例えば、特許文献1参照)   Conventionally, mobile communication devices such as mobile phones and PDAs are used by switching to generate a buzzer or melody sound or vibrate the device housing without making a sound to notify the user of an incoming call. Is configured to do. Therefore, a structure has been adopted in which a speaker for generating sound similar to a small speaker and a vibrating body that generates vibration by rotating an eccentric weight with a small motor are combined. However, incorporating both the speaker and the vibrator in this manner is disadvantageous in terms of downsizing and cost reduction of the device. Therefore, in recent years, a multi-function vibration actuator (vibrating body), which is a magnetically driven actuator that generates both sound and vibration, has been used. When such multi-function vibration actuators are impacted by an external force, they may be deformed or damaged, resulting in deterioration of resonance characteristics, or internal parts coming into contact with each other, which may cause scratching noise during operation. There is. A multifunctional sounding body that addresses this is disclosed. (For example, see Patent Document 1)

特開2000−278794号(第3頁、図1、図2)JP 2000-278794 (3rd page, FIG. 1, FIG. 2)

上記した特許文献1に開示されている多機能型発音体アクチュエータの構造は、図4で示されるように、プラスチックなどで作られたケース21の下面側にステンレス鋼などの金属の第2振動板22を固定し、これに純鉄やパーマロイなどの磁性材料のヨーク23が点溶接で結合してある。ヨーク23には磁石24が固定され、磁石24の上面に磁性材料のトッププレート25が積層・固着されている。前記磁石24、トッププレート25及びヨーク23で磁気回路部26を構成する。前記ケース21の上面側にはポリイミド、ポリエステルなどで成形した第1の振動板27が取付けられ、その下面にボイスコイル28が固定されている。ボイスコイル28はトッププレート25の外周とヨーク23の内側で作られる磁気ギャップg内に位置している。前記ボイスコイル28に可聴周波数の信号電流を流すと、第1振動板27が振動してブザー音、メロディ、音声など可聴音を発し、それより低い信号を用いると、ヨーク23や磁石24が一体になった第2振動板22が振動し、この振動はケース21を経てこの発音体を組み込んだ携帯機器に伝わる。   As shown in FIG. 4, the structure of the multi-function sounding body actuator disclosed in Patent Document 1 described above is a second diaphragm made of metal such as stainless steel on the lower surface side of a case 21 made of plastic or the like. 22 is fixed, and a yoke 23 made of a magnetic material such as pure iron or permalloy is joined to this by spot welding. A magnet 24 is fixed to the yoke 23, and a top plate 25 made of a magnetic material is laminated and fixed on the upper surface of the magnet 24. The magnet 24, the top plate 25, and the yoke 23 constitute a magnetic circuit unit 26. A first diaphragm 27 formed of polyimide, polyester, or the like is attached to the upper surface side of the case 21, and a voice coil 28 is fixed to the lower surface thereof. The voice coil 28 is located in a magnetic gap g formed on the outer periphery of the top plate 25 and the inner side of the yoke 23. When a signal current having an audible frequency is passed through the voice coil 28, the first diaphragm 27 vibrates and emits an audible sound such as a buzzer sound, a melody or a voice. When a lower signal is used, the yoke 23 and the magnet 24 are integrated. The second diaphragm 22 becomes a vibration, and this vibration is transmitted through the case 21 to the portable device in which the sounding body is incorporated.

前記ヨーク23の外周に鍔部29を設け、一方、ケース21の内周に凹部30を設けて、前記鍔部29を前記凹部30内に位置させるように構成する。こうすることにより、発音体が外部から衝撃を受けた時に、ヨーク23が大きく変位しようとしても、鍔部29が前記凹部30の上下の肩部31、32に当接してそれ以上は変位しないので、第2振動板22が変形したり、あるいはヨーク23やトッププレート25が第1振動板27やこれに固定されたボイスコイル28に衝突して、これらの部品を変形させたり破損させたりすることを防止する。   A flange 29 is provided on the outer periphery of the yoke 23, while a recess 30 is provided on the inner periphery of the case 21 so that the flange 29 is positioned in the recess 30. By doing so, when the sounding body receives an impact from the outside, even if the yoke 23 tends to be greatly displaced, the collar portion 29 abuts on the upper and lower shoulder portions 31 and 32 of the concave portion 30 and no further displacement occurs. The second diaphragm 22 is deformed, or the yoke 23 and the top plate 25 collide with the first diaphragm 27 and the voice coil 28 fixed to the first diaphragm 27 to deform or damage these components. To prevent.

解決しようとする問題点としては、上記した特許文献1に開示した多機能型発音体で、
衝撃緩衝部はヨークの外周部を延長した構造にしている。このような構造の場合は形状が
複雑で加工が困難である。などの問題があった。
As a problem to be solved, the multifunctional sounding body disclosed in Patent Document 1 described above,
The shock absorbing portion has a structure in which the outer peripheral portion of the yoke is extended. In the case of such a structure, the shape is complicated and difficult to process. There were problems such as.

本発明は、上述の欠点を解消するもので、その目的は、磁気回路部にストッパー部材を別部品として配設するため加工が容易であると共に、製品に衝撃が加わった際の磁気回路部の過剰振幅による故障を防止する。また、ストッパー部材を別部品にするため、その分、磁気回路部へ付加質量が加わり振動特性が向上する、薄型で信頼性に優れた電気音響変換器を提供するものである。   The present invention eliminates the above-described drawbacks, and its purpose is to dispose a stopper member as a separate part in the magnetic circuit portion, which is easy to process, and the magnetic circuit portion when an impact is applied to the product. Prevents failure due to excessive amplitude. In addition, since the stopper member is a separate part, a thin and highly reliable electroacoustic transducer in which additional mass is added to the magnetic circuit portion and vibration characteristics are improved is provided.

上記目的を達成するために、本発明における電気音響変換器は、碗形状をしたヨークと、該ヨークの内部に順次積層される板状の磁石およびトッププレートから構成される磁気回路部と、該磁気回路部のヨークの側壁の内周部とトッププレートの外周部との間に形成される空隙内に配置されるボイスコイルと、前記磁気回路部の外方でボイスコイルを保持する振動板と、振動伝達部のケースに保持され、前記磁気回路部を保持するサスペンションとよりなる電気音響変換器において、前記磁気回路部に曲げ加工を施したストッパー部材を配設したことを特徴とするものである。   In order to achieve the above object, an electroacoustic transducer according to the present invention includes a yoke having a bowl shape, a magnetic circuit unit including a plate-like magnet and a top plate that are sequentially stacked inside the yoke, A voice coil disposed in a gap formed between the inner peripheral portion of the side wall of the yoke of the magnetic circuit portion and the outer peripheral portion of the top plate; and a diaphragm for holding the voice coil outside the magnetic circuit portion. An electroacoustic transducer comprising a suspension that is held by a case of a vibration transmission unit and that holds the magnetic circuit unit, wherein a stopper member that is bent on the magnetic circuit unit is disposed. is there.

また、前記磁気回路部に配設したストッパー部材は、金属または樹脂部材であることを特徴とするものである。   Further, the stopper member disposed in the magnetic circuit portion is a metal or a resin member.

また、前記磁気回路部に配設されたストッパー部材は、前記ヨークの碗形状の鍔部下面とヨークの外周部に固定されたリング状の錘との間に挟持されていることを特徴とすることを特徴とするものである。   The stopper member disposed in the magnetic circuit portion is sandwiched between a lower surface of the flange-shaped flange portion of the yoke and a ring-shaped weight fixed to the outer peripheral portion of the yoke. It is characterized by this.

本発明の電気音響変換器は、磁気回路部に衝撃吸収材としてのストッパー部材を別部品として配設することにより部品加工が容易である。また、ストッパー部材を別部品にするため、その分、磁気回路部へ付加質量が加わり振動特性の安定化が図られ、信頼性に優れ薄型の電気音響変換器を提供することが可能である。   The electroacoustic transducer of the present invention can be easily processed by disposing a stopper member as a shock absorbing material as a separate component in the magnetic circuit portion. In addition, since the stopper member is a separate part, an additional mass is added to the magnetic circuit portion, and the vibration characteristics are stabilized. Thus, it is possible to provide a thin electroacoustic transducer having excellent reliability.

本発明の電気音響変換器について、図面に基づいて説明する。   The electroacoustic transducer of the present invention will be described with reference to the drawings.

図1は、本発明の実施例に係わる電気音響変換器の断面図である。図1において、従来例と同様に、この振動体の磁気回路部1は、略碗形状をしたヨーク2と、該ヨーク2の内部に順次積み重ねられる平板状の磁石3およびトッププレート4から構成される。そして、この磁気回路部1と、ヨーク2の側壁の内周部と平板状のトッププレート4の外周部との間に形成される空隙(ギャップ)g内にボイスコイル5を配設する。該ボイスコイル5は前記磁気回路部1の外方でケース6の上方において、振動板7に固定されている。   FIG. 1 is a cross-sectional view of an electroacoustic transducer according to an embodiment of the present invention. In FIG. 1, as in the conventional example, the magnetic circuit portion 1 of the vibrating body is composed of a yoke 2 having a substantially bowl shape, a flat magnet 3 and a top plate 4 sequentially stacked inside the yoke 2. The The voice coil 5 is disposed in a gap (gap) g formed between the magnetic circuit portion 1 and the inner peripheral portion of the side wall of the yoke 2 and the outer peripheral portion of the flat top plate 4. The voice coil 5 is fixed to the diaphragm 7 outside the magnetic circuit unit 1 and above the case 6.

前記磁気回路部1を構成するヨーク2にはサスペンション8が固着されている。サスペンション8はヨーク2の外側に向かって延びる複数の腕部を有し、この腕部の外端はケース6にインサートモールドなどにより固着されている。従って、磁気回路部1はサスペンション8の腕状部に弾性的に懸架され、一体となって軸方向に振動することができる。上カバー9は前記ケース6の上部に取着され、背面カバー10は下面に取着されたである。   A suspension 8 is fixed to the yoke 2 constituting the magnetic circuit unit 1. The suspension 8 has a plurality of arm portions extending toward the outside of the yoke 2, and the outer ends of the arm portions are fixed to the case 6 by an insert mold or the like. Therefore, the magnetic circuit portion 1 is elastically suspended on the arm-like portion of the suspension 8 and can vibrate in the axial direction as a unit. The upper cover 9 is attached to the upper part of the case 6 and the back cover 10 is attached to the lower surface.

前記ヨーク2の外周のリング状の部分には鉄やタングステン合金などの高比重の磁性材料によりなる付加質量(錘)11がヨーク2に一体的に結合固定されている。前記ヨーク2の碗形状の鍔部下面とヨーク2の外周部に固定されたリング状の錘11との間には後述するストッパー部材12が挟持されている。   An additional mass (weight) 11 made of a high specific gravity magnetic material such as iron or tungsten alloy is integrally coupled and fixed to the yoke 2 at a ring-shaped portion on the outer periphery of the yoke 2. A stopper member 12, which will be described later, is sandwiched between the lower surface of the flange-shaped flange portion of the yoke 2 and a ring-shaped weight 11 fixed to the outer periphery of the yoke 2.

図2(a)は、ストッパー部材の平面図、図2(b)は、図2(a)の断面図、図3(a)は、磁気回路部にストッパー部材を配設した平面図、図3(b)は、図3(a)の断面図である。図2において、ストッパー部材12は、金属薄板をリング状にプレス抜きし、外周部を皿状に折り曲げて形成する。中央部には前記ヨーク2の外周のリング状の部分に嵌合する貫通孔12aと外周部には折り曲げられた鍔部12bが形成されている。図3において、磁気回路部1を構成するヨーク2の碗形状の鍔部下面とヨーク2の外周部に固定されたリング状の錘11との間にストッパー部材12が挟持される。前記ストッパー部材12は樹脂部材で成形しても良い。   2A is a plan view of the stopper member, FIG. 2B is a cross-sectional view of FIG. 2A, and FIG. 3A is a plan view in which the stopper member is disposed in the magnetic circuit portion. 3 (b) is a cross-sectional view of FIG. 3 (a). In FIG. 2, the stopper member 12 is formed by pressing a thin metal plate into a ring shape and bending the outer peripheral portion into a dish shape. A through hole 12a that fits in the ring-shaped portion on the outer periphery of the yoke 2 is formed in the center portion, and a bent flange portion 12b is formed on the outer periphery portion. In FIG. 3, a stopper member 12 is sandwiched between the lower surface of the flange-shaped flange portion of the yoke 2 constituting the magnetic circuit portion 1 and the ring-shaped weight 11 fixed to the outer peripheral portion of the yoke 2. The stopper member 12 may be formed of a resin member.

以上述べた構成の電気音響変換器の作用・効果について説明する。図1において、前記ストッパー部材12の外周部で折り曲げられた鍔部12bは、ケース6の内周の凹部13内に位置させるように構成する。こうすることにより、電気音響変換器が外部から衝撃を受けた時に、ヨーク2が大きく変位しようとしても、鍔部12bが前記凹部13の上下の肩部14(ケース側)、15(背面カバー側)に当接してそれ以上は変位しないので、ヨーク2やトッププレート4が振動板7やこれに固定されたボイスコイル5に衝突して、これらの部品を変形させたり破損させたりすることを防止する。ストッパー部材12を別部品として配設することにより、部品加工が容易である。また、ストッパー部材12を別部品にするため、前記錘11と相乗して、その分、磁気回路部へ付加質量が加わり振動特性の安定化が図られ、信頼性に優れ薄型の電気音響変換器を提供することが可能である。   The operation and effect of the electroacoustic transducer having the above-described configuration will be described. In FIG. 1, the flange portion 12 b bent at the outer peripheral portion of the stopper member 12 is configured to be positioned in the concave portion 13 on the inner periphery of the case 6. In this way, when the electroacoustic transducer receives an impact from the outside, even if the yoke 2 tends to be greatly displaced, the flange portion 12b has the upper and lower shoulder portions 14 (case side) and 15 (rear cover side) of the recess 13. ), And the yoke 2 and the top plate 4 are prevented from colliding with the diaphragm 7 and the voice coil 5 fixed thereto to deform or damage these components. To do. By disposing the stopper member 12 as a separate part, parts processing is easy. In addition, since the stopper member 12 is a separate part, in synergy with the weight 11, an additional mass is added to the magnetic circuit portion to stabilize the vibration characteristics, and the thin electroacoustic transducer is excellent in reliability. Can be provided.

本発明の実施例に係わる電気音響変換器の断面図である。It is sectional drawing of the electroacoustic transducer concerning the Example of this invention. (a)はストッパー部材の平面図、(b)は(a)の断面図である。(A) is a top view of a stopper member, (b) is sectional drawing of (a). (a)は磁気回路部にストッパー部材を配設した平面図、(b)は(a)の断面図である。(A) is the top view which arrange | positioned the stopper member in the magnetic circuit part, (b) is sectional drawing of (a). 従来の多機能型発音体の断面図である。It is sectional drawing of the conventional multifunction type sounding body.

符号の説明Explanation of symbols

1 磁気回路部
2 ヨーク
3 磁石
4 トッププレート
5 ボイスコイル
6 ケース
7 振動板
8 サスペンション
9 上カバー
10 背面カバー
11 付加質量(錘)
12 ストッパー部材
12a 貫通孔
12b ストッパー部材鍔部
DESCRIPTION OF SYMBOLS 1 Magnetic circuit part 2 Yoke 3 Magnet 4 Top plate 5 Voice coil 6 Case 7 Diaphragm 8 Suspension 9 Upper cover 10 Back cover 11 Additional mass (weight)
12 Stopper member 12a Through hole 12b Stopper member collar

Claims (3)

碗形状をしたヨークと、該ヨークの内部に順次積層される板状の磁石およびトッププレートから構成される磁気回路部と、該磁気回路部のヨークの側壁の内周部とトッププレートの外周部との間に形成される空隙内に配置されるボイスコイルと、前記磁気回路部の外方でボイスコイルを保持する振動板と、振動伝達部のケースに保持され、前記磁気回路部を保持するサスペンションとよりなる電気音響変換器において、前記磁気回路部に曲げ加工を施したストッパー部材を配設したことを特徴とする電気音響変換器。   A yoke having a bowl shape, a magnetic circuit portion composed of a plate-like magnet and a top plate sequentially stacked inside the yoke, an inner peripheral portion of the side wall of the yoke of the magnetic circuit portion, and an outer peripheral portion of the top plate A voice coil disposed in a gap formed between the magnetic circuit unit, a diaphragm holding the voice coil outside the magnetic circuit unit, and a case of the vibration transmission unit to hold the magnetic circuit unit An electroacoustic transducer comprising a suspension, wherein a stopper member that is bent on the magnetic circuit portion is disposed. 前記磁気回路部に配設したストッパー部材は、金属または樹脂部材であることを特徴とする請求項1記載の電気音響変換器。   The electroacoustic transducer according to claim 1, wherein the stopper member disposed in the magnetic circuit unit is a metal or a resin member. 前記磁気回路部に配設されたストッパー部材は、前記ヨークの碗形状の鍔部下面とヨークの外周部に固定されたリング状の錘との間に挟持されていることを特徴とする請求項1または2記載の電気音響変換器。
The stopper member disposed in the magnetic circuit portion is sandwiched between a lower surface of the flange-shaped flange portion of the yoke and a ring-shaped weight fixed to the outer peripheral portion of the yoke. The electroacoustic transducer according to 1 or 2.
JP2007080775A 2007-03-27 2007-03-27 Electroacoustic transducer Pending JP2008244710A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
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CN101931846A (en) * 2009-06-24 2010-12-29 宝星电子股份有限公司 Multifunction micro speaker
WO2011013462A1 (en) * 2009-07-29 2011-02-03 三洋電機株式会社 Electroacoustic transducer having vibration function
CN102273226A (en) * 2010-01-06 2011-12-07 宝星电子株式会社 Multifunctional microspeaker
CN114501256A (en) * 2022-03-23 2022-05-13 歌尔股份有限公司 Sound production device and electronic equipment
WO2022201969A1 (en) * 2021-03-24 2022-09-29 富士フイルム株式会社 Ultrasonic system and method for controlling ultrasonic system

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101931846A (en) * 2009-06-24 2010-12-29 宝星电子股份有限公司 Multifunction micro speaker
WO2011013462A1 (en) * 2009-07-29 2011-02-03 三洋電機株式会社 Electroacoustic transducer having vibration function
CN102273226A (en) * 2010-01-06 2011-12-07 宝星电子株式会社 Multifunctional microspeaker
WO2022201969A1 (en) * 2021-03-24 2022-09-29 富士フイルム株式会社 Ultrasonic system and method for controlling ultrasonic system
CN114501256A (en) * 2022-03-23 2022-05-13 歌尔股份有限公司 Sound production device and electronic equipment
CN114501256B (en) * 2022-03-23 2023-09-29 歌尔股份有限公司 Sound producing device and electronic equipment

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