JPH06204778A - Manufacture of piezoelectric vibrator - Google Patents

Manufacture of piezoelectric vibrator

Info

Publication number
JPH06204778A
JPH06204778A JP101293A JP101293A JPH06204778A JP H06204778 A JPH06204778 A JP H06204778A JP 101293 A JP101293 A JP 101293A JP 101293 A JP101293 A JP 101293A JP H06204778 A JPH06204778 A JP H06204778A
Authority
JP
Japan
Prior art keywords
piezoelectric vibrator
piezoelectric
resonance frequency
vibrator
processing
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.)
Pending
Application number
JP101293A
Other languages
Japanese (ja)
Inventor
Osamu Kawasaki
修 川崎
Toshiharu Okada
俊治 岡田
Shinichi Mizuguchi
信一 水口
Yukihiko Ise
悠紀彦 伊勢
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP101293A priority Critical patent/JPH06204778A/en
Publication of JPH06204778A publication Critical patent/JPH06204778A/en
Pending legal-status Critical Current

Links

Landscapes

  • Piezo-Electric Transducers For Audible Bands (AREA)
  • Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
  • Ultra Sonic Daignosis Equipment (AREA)

Abstract

PURPOSE:To reduce the heat generation at processing and to obtain the adjustment method of a resonance frequency with high accuracy and without deterioration in the material and the characteristic of the piezoelectric vibrator with respect to the manufacture of a piezoelectric element in which part of the piezoelectric vibrator is removed to adjust the resonance frequency of the piezoelectric vibrator. CONSTITUTION:A piezoelectric vibrator 1 is formed to be a paper-tablet in which an electrode 2 is provided to opposite faces, and the lengthwise vibration displacing the length of the vibrator 1 is stimulated by applying an AC electric field to the electrode 2. The resonance frequency of the lengthwise vibration depends on a type of material and the length of the element of the piezoelectric vibrator 1. Thus, an end face of the piezoelectric vibrator 1 is processed to scrape the piezoelectric material with a laser beam by DELTAt each DELTAt is smaller than a laser beam diameter) from the end face. Thus, the production of residual material due to processing is prevented and the processing time is reduced and the manufacture with less thermal deterioration is obtained.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、圧電セラミック、水
晶、リチウム酸ニオブ等の圧電材料を用いた圧電振動子
の製造方法に関し、より詳しくは、所望の値の共振周波
数を有する圧電素子の製造方法に関するものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a piezoelectric vibrator using a piezoelectric material such as piezoelectric ceramic, crystal, niobium lithium oxide, and more particularly, manufacturing a piezoelectric element having a resonance frequency of a desired value. It is about the method.

【0002】[0002]

【従来の技術】以下に、図面を参照しながら、圧電セラ
ミック、水晶、リチウム酸ニオブ等の圧電材料を用いた
圧電振動子の共振周波数調整方法の従来技術について説
明を行う。
2. Description of the Related Art A conventional technique of a resonance frequency adjusting method for a piezoelectric vibrator using a piezoelectric material such as piezoelectric ceramic, crystal, niobium lithium oxide, etc. will be described below with reference to the drawings.

【0003】メカニカルフィルタや発振子等に用いられ
る圧電振動子は、圧電セラミック、水晶、リチウム酸ニ
オブ等の材料で作られている。そして、圧電振動子の共
振周波数はその材料定数と加工寸法によって決まる。従
って、圧電振動子の材料が決まれば共振周波数はその寸
法によって決まる。
Piezoelectric vibrators used for mechanical filters, oscillators, etc. are made of materials such as piezoelectric ceramics, crystal, and niobium lithium oxide. The resonance frequency of the piezoelectric vibrator is determined by its material constant and processing size. Therefore, if the material of the piezoelectric vibrator is determined, the resonance frequency is determined by its size.

【0004】ところで、一般的には圧電材料の材料定数
はばらつきを持つために、所定の共振周波数を得るにも
寸法を一意的に決めることができず、材料定数を計測し
た後に振動子を加工することにより、共振周波数の調整
を行わなければならない。
By the way, in general, since the material constants of piezoelectric materials vary, it is not possible to uniquely determine the dimensions in order to obtain a predetermined resonance frequency. After measuring the material constants, the vibrator is processed. Therefore, the resonance frequency must be adjusted.

【0005】しかし、材料定数は同一ロット内でもばら
つき振動子の形態にした後に微調整が必要になる。材料
定数のばらつきの大きい圧電セラミックでは、とくに調
整の絶対値が大きく共振周波数の調整は重要な工程であ
る。
However, the material constants need to be finely adjusted even in the same lot after forming the variation oscillator. For piezoelectric ceramics with large variations in material constants, the absolute value of adjustment is particularly large, and adjusting the resonance frequency is an important step.

【0006】図3は、圧電セラミック等の圧電材料で作
られた従来の圧電振動子の斜視図であり、対抗する主面
に電極が形成され、この電極間に電界を印加すれば角板
の拡がり振動が励振される。同図では、圧電振動子の共
振周波数を調整するために、4つの各辺の中央部を砥石
またはダイヤモンド・カッティング・ホイール等の機械
加工方法またはレーザービーム加工で溝加工することに
より共振周波数の調整をしている。
FIG. 3 is a perspective view of a conventional piezoelectric vibrator made of a piezoelectric material such as a piezoelectric ceramic. Electrodes are formed on opposing main surfaces, and if an electric field is applied between the electrodes, a rectangular plate is formed. Spreading vibration is excited. In the same figure, in order to adjust the resonance frequency of the piezoelectric vibrator, the resonance frequency is adjusted by machining the central portion of each of the four sides with a machining method such as a grindstone or a diamond cutting wheel, or by grooving with laser beam Are doing

【0007】図4は、圧電セラミック等の圧電材料で作
られたもう1つの従来の圧電振動子の斜視図であり、同
様に角板の拡がり振動を用いている。同図では、圧電振
動子の共振周波数を調整するために、4つの各角を砥石
またはダイヤモンド・カッティング・ホイール等の機械
加工方法またはレーザービーム加工で切断して落とすこ
とで共振周波数の調整をしている。
FIG. 4 is a perspective view of another conventional piezoelectric vibrator made of a piezoelectric material such as piezoelectric ceramic, and similarly uses the spreading vibration of a square plate. In the figure, in order to adjust the resonance frequency of the piezoelectric vibrator, the resonance frequency is adjusted by cutting and dropping each of the four corners with a machining method such as a grindstone or a diamond cutting wheel or laser beam processing. ing.

【0008】[0008]

【発明が解決しようとする課題】砥石またはダイヤモン
ド・カッティング・ホイール等の機械加工方法で圧電振
動子の共振周波数の調整をする場合には、加工精度が悪
いので正確な共振周波数の調整が困難であり、また調整
の歩どまりが悪いという課題があった。加えて、機械加
工法では加工時に圧電振動子に力が加わるため、損傷を
与え易くまた調整のための加工時の圧電振動子の保持な
どの取扱いも面倒であるという課題があった。
When the resonance frequency of the piezoelectric vibrator is adjusted by a machining method such as a grindstone or a diamond cutting wheel, the machining accuracy is poor and it is difficult to adjust the resonance frequency accurately. There was also a problem that the adjustment yield was poor. In addition, in the machining method, since a force is applied to the piezoelectric vibrator during processing, there is a problem that it is easily damaged and handling such as holding the piezoelectric vibrator during processing for adjustment is troublesome.

【0009】レーザービーム加工で圧電振動子の共振周
波数の調整をする場合には、従来の4つの各辺の中央部
にレーザービーム幅よりも大きい加工溝加工するか、4
つの各角を落とすという方法では、加工に時間がかかる
ために圧電振動子に熱が発生し、この熱のため圧電振動
子が劣化するという課題があった。また加工時の溶融物
や残留物が振動子に残りやすいという課題もあった。
When the resonance frequency of the piezoelectric vibrator is adjusted by laser beam machining, a conventional machining groove having a width larger than the laser beam width is formed at the center of each of the four sides.
In the method of dropping each of the two corners, there is a problem that heat is generated in the piezoelectric vibrator due to the long processing time and the heat deteriorates the piezoelectric vibrator. In addition, there is a problem that a melt or a residue during processing tends to remain on the vibrator.

【0010】例えば、図4に示すように、板状の圧電材
料の一面側からレーザーを照射して角部を切断除去する
場合のレーザー加工のメカニズムは以下のようになる。
For example, as shown in FIG. 4, the mechanism of laser processing in the case of irradiating a laser from one surface side of a plate-shaped piezoelectric material to cut and remove a corner is as follows.

【0011】レーザー照射による加熱によって、圧電材
料の加熱、溶融あるいは蒸発が始まる。この加熱、溶融
あるいは蒸発は、当然にレーザーが照射される面側から
開始されるから、レーザー照射面側では、溶融状態であ
るのに対して、レーザー照射面と反対の面側では固体
(非溶融)状態である状況が生じる。
The heating by the laser irradiation starts heating, melting or evaporation of the piezoelectric material. This heating, melting, or evaporation naturally starts from the surface side to which the laser is irradiated, so that the laser irradiation surface side is in a molten state, while the surface opposite to the laser irradiation surface is solid (non-solid). The situation arises that is in the "melted" state.

【0012】この状況下では、圧電材料の溶融部では、
その内部において、比較的低融点の材料が急激に気化し
て爆発的な体積膨張を生じ、溶融している圧電材料を周
囲に飛散させる。この場合、圧電材料の溶融部は、その
底面(レーザー照射側と反対の面側)と側面を非溶融状
態の圧電材料で取り囲まれているために、この飛散物
は、レーザーの照射面側に飛散することとなり、レーザ
ー照射部の周辺には、この飛散物が付着し、圧電材料を
汚染することとなる。
Under this circumstance, in the fused portion of the piezoelectric material,
Inside, a material having a relatively low melting point is rapidly vaporized to cause explosive volume expansion, and the molten piezoelectric material is scattered around. In this case, since the melted portion of the piezoelectric material is surrounded by the non-melted piezoelectric material on the bottom surface (the surface opposite to the laser irradiation side) and the side surface, this scattered material is on the laser irradiation surface side. As a result of scattering, the scattered matter adheres to the periphery of the laser irradiation portion and contaminates the piezoelectric material.

【0013】更に、レーザー加工により切断が完了した
時には、レーザー照射面と反対の面側において、切断部
の稜線に、いわゆるバリと呼ばれる残留物が形成される
のが一般的である。
Further, when the cutting is completed by laser processing, a residue called a burr is generally formed on the ridge line of the cut portion on the side opposite to the laser irradiation surface.

【0014】また、レーザー照射面と反対側の面が溶融
状態となるのは、基本的には、レーザー照射面側からの
熱伝導等による加熱で溶融状態となるか、あるいは、レ
ーザー照射面側の材料が蒸発して、反対面側に直接的に
レーザー照射が行われて加熱されるかであるから、反対
側の面が溶融状態となるまでには、比較的、時間を要
し、またその時間において、溶融部の熱が周囲に伝導し
て圧電材料に熱的な劣化を与える。特に、キュリー点の
低い圧電セラミックの場合には、前記の熱劣化が特に問
題であり、レーザービーム加工を共振周波数調整に用い
ることが困難であった。また、4つの箇所を加工するた
めに加工時間がかかるという課題もあった。
The surface opposite to the laser-irradiated surface is in a molten state basically because the surface is in a molten state by heating due to heat conduction from the laser-irradiated surface side or the laser-irradiated surface side. It is relatively time-consuming until the opposite surface becomes in a molten state, because the material is vaporized and the opposite surface is directly irradiated with laser and heated. At that time, the heat of the melted portion is conducted to the surroundings to cause thermal deterioration of the piezoelectric material. In particular, in the case of a piezoelectric ceramic having a low Curie point, the above-mentioned thermal deterioration is a particular problem, and it is difficult to use laser beam processing for resonance frequency adjustment. Further, there is a problem that it takes a long processing time to process the four places.

【0015】また、バリや付着した飛散物は、製造後に
おいて脱落しやすいために、共振周波数が変動しやすい
という課題も有していた。
Further, since burrs and adhered scattered substances are likely to fall off after manufacturing, there is a problem that the resonance frequency is likely to change.

【0016】[0016]

【課題を解決するための手段】圧電振動子の端面を、レ
ーザービーム加工にて端面から順次加工することによ
り、圧電振動子の共振周波数を調整する。
A resonance frequency of a piezoelectric vibrator is adjusted by sequentially processing the end face of the piezoelectric vibrator by laser beam processing.

【0017】[0017]

【作用】圧電材料を用いた圧電振動子において、圧電振
動子の端面をレーザービーム加工にて端面から順次加工
することにより、加工による圧電振動子の熱発生を小さ
くするとともに、残留物が振動子上に残らないようにす
る。また振動子の保持などの取扱いを容易にして、圧電
振動子の劣化のない信頼性と精度の高い共振周波数の調
整方法を実現する。
[Function] In the piezoelectric vibrator using the piezoelectric material, the end face of the piezoelectric vibrator is sequentially processed by laser beam processing, so that heat generation of the piezoelectric vibrator due to the processing is reduced and the residue is generated by the vibrator. Do not leave it on top. Further, it facilitates handling such as holding the vibrator, and realizes a method of adjusting the resonance frequency with high reliability and high accuracy without deterioration of the piezoelectric vibrator.

【0018】[0018]

【実施例】以下、図面に従って本発明の実施例について
詳細な説明を行う。
Embodiments of the present invention will be described in detail below with reference to the drawings.

【0019】図1は本発明の圧電振動子の周波数調整方
法の1実施例の斜視図である。同図において、1は圧電
セラミック、水晶、リチウム酸ニオブ等の材料で作ら
れ、対抗する面に電極2を付けた短冊状の圧電振動子で
あり、電極2に交流電界を印加することにより、振動子
1の長さ方向に主変位を持つ長さ振動モードを励振する
ことができる。この長さ振動の共振周波数は、圧電振動
子1の材料と素子長さ寸法で決まり、共振周波数の調整
は長さ寸法を変えることで調整する。
FIG. 1 is a perspective view of an embodiment of a frequency adjusting method for a piezoelectric vibrator according to the present invention. In FIG. 1, reference numeral 1 denotes a strip-shaped piezoelectric vibrator made of a material such as piezoelectric ceramic, crystal, niobium lithium oxide, etc., and having electrodes 2 attached to opposite surfaces thereof. By applying an alternating electric field to the electrodes 2, A length vibration mode having a main displacement in the length direction of the vibrator 1 can be excited. The resonance frequency of the length vibration is determined by the material of the piezoelectric vibrator 1 and the element length dimension, and the resonance frequency is adjusted by changing the length dimension.

【0020】圧電振動子1の1つの端面部を、図1に示
すように端面に沿って端面からΔtだけずつレーザービ
ームにより圧電材料をそぎ落とすように加工する。つま
り、図2(a)に示すように圧電振動子1の端面部をレ
ーザーで落として加工するのではなく、図2(b)に示
すようにレーザービームのビーム幅よりも小さい領域を
そぎ落とすように加工する。
As shown in FIG. 1, one end face portion of the piezoelectric vibrator 1 is processed so that the piezoelectric material is scraped off by a laser beam along the end face by Δt from the end face. That is, the end face portion of the piezoelectric vibrator 1 is not processed by laser cutting as shown in FIG. 2A, but a region smaller than the beam width of the laser beam is cut off as shown in FIG. 2B. To process.

【0021】例えばレーザービームの幅が50ミクロン
の時には、加工する幅Δtは約5〜30ミクロン程度に
設定する。これにより、レーザー加工の高速化が実現で
きるので、圧電素子の熱の発生を防ぐことができる。ま
た、加工時の残留物が削り取られてしまうのできれいな
加工面が得られる。
For example, when the width of the laser beam is 50 μm, the processing width Δt is set to about 5 to 30 μm. As a result, the speed of laser processing can be increased, and heat generation of the piezoelectric element can be prevented. In addition, since the residue during machining is scraped off, a clean machined surface can be obtained.

【0022】ここでは、本発明の実施例として、長さ振
動の圧電振動子の共振周波数を振動子の1つの端面で調
整する場合について述べたが、両端を加工することによ
り調整しても同様であることはいうまでもない。また、
他の振動モードを使った圧電振動子を同様にレーザービ
ームでそぎ落とすように端面から加工して共振周波数の
調整することも同様に容易である。
As an example of the present invention, the case where the resonance frequency of the length-vibrating piezoelectric vibrator is adjusted by one end face of the vibrator has been described, but the same is true by adjusting both ends. Needless to say. Also,
Similarly, it is also easy to adjust the resonance frequency by processing the piezoelectric vibrator using another vibration mode from the end face so as to be cut off by the laser beam.

【0023】なお、上記実施例では、熱エネルギーとし
てレーザーを用いたが、必ずしもコヒーレント光である
必要はなく、通常の光を集光して用いても良い。
Although the laser is used as the thermal energy in the above embodiment, it is not always necessary to use coherent light, and ordinary light may be condensed and used.

【0024】[0024]

【発明の効果】圧電材料を用いた圧電振動子において、
圧電振動子の端面をレーザービーム加工にて端面から順
次そぎ落とす様に加工することにより、加工速度をあげ
ることができるので、加工による圧電振動子の熱発生を
小さくすることができる。また、加工の残留物が圧電振
動子の端面に残るのを防止できるので、圧電振動子の材
料劣化および特性劣化のない信頼性の高い共振周波数調
整方法を実現することができる。また調整加工時に圧電
振動子に力がかからないので、振動子の保持などが容易
になり、例えばフィルタ、発振子等として実装した後に
調整加工をすることができる。
In the piezoelectric vibrator using the piezoelectric material,
Since the processing speed can be increased by processing the end faces of the piezoelectric vibrator by laser beam processing so that the end faces are sequentially cut off from the end faces, heat generation of the piezoelectric vibrator due to the processing can be reduced. Further, since it is possible to prevent the processing residue from remaining on the end face of the piezoelectric vibrator, it is possible to realize a highly reliable resonance frequency adjusting method without material deterioration and characteristic deterioration of the piezoelectric vibrator. Further, since no force is applied to the piezoelectric vibrator during the adjustment processing, it becomes easy to hold the vibrator, and the adjustment processing can be performed after the piezoelectric vibrator is mounted as, for example, a filter or an oscillator.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明の圧電振動子の製造方法の一実施例を示
す斜視図
FIG. 1 is a perspective view showing an embodiment of a method for manufacturing a piezoelectric vibrator of the present invention.

【図2】同実施例の補足説明図FIG. 2 is a supplementary explanatory diagram of the embodiment.

【図3】従来の圧電振動子の製造方法を示す斜視図FIG. 3 is a perspective view showing a method for manufacturing a conventional piezoelectric vibrator.

【図4】他の従来の圧電振動子の製造方法を示す斜視図FIG. 4 is a perspective view showing another conventional method for manufacturing a piezoelectric vibrator.

【符号の説明】[Explanation of symbols]

1、3、4 圧電振動子 2 電極 1, 3, 4 Piezoelectric vibrator 2 electrodes

───────────────────────────────────────────────────── フロントページの続き (72)発明者 伊勢 悠紀彦 大阪府門真市大字門真1006番地 松下電器 産業株式会社内 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Yukihiko Ise 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】圧電材料を用いた圧電振動子において、上
記圧電振動子の端面部に熱エネルギーを照射して、端面
から前記圧電材料を微少量づつ除去することにより、上
記圧電振動子の共振周波数を所望の値に調整することを
特徴とする圧電振動子の製造方法。
1. A piezoelectric vibrator using a piezoelectric material, wherein the end face of the piezoelectric vibrator is irradiated with thermal energy to remove the piezoelectric material in minute amounts from the end face, thereby causing resonance of the piezoelectric vibrator. A method of manufacturing a piezoelectric vibrator, comprising adjusting a frequency to a desired value.
JP101293A 1993-01-07 1993-01-07 Manufacture of piezoelectric vibrator Pending JPH06204778A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP101293A JPH06204778A (en) 1993-01-07 1993-01-07 Manufacture of piezoelectric vibrator

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP101293A JPH06204778A (en) 1993-01-07 1993-01-07 Manufacture of piezoelectric vibrator

Publications (1)

Publication Number Publication Date
JPH06204778A true JPH06204778A (en) 1994-07-22

Family

ID=11489668

Family Applications (1)

Application Number Title Priority Date Filing Date
JP101293A Pending JPH06204778A (en) 1993-01-07 1993-01-07 Manufacture of piezoelectric vibrator

Country Status (1)

Country Link
JP (1) JPH06204778A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
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US7245057B2 (en) 2000-12-15 2007-07-17 Intel Corporation Micro-electromechanical structure resonator frequency adjustment using radiant energy trimming and laser/focused ion beam assisted deposition
EP2063470A1 (en) 2005-02-10 2009-05-27 Seiko Epson Corporation Piezoelectric vibrator, method for adjusting piezoelectric vibrator, piezoelectric actuator, timepiece, and electronic device
US8736144B2 (en) 2010-12-10 2014-05-27 Canon Kabushiki Kaisha Vibration type driving apparatus

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7245057B2 (en) 2000-12-15 2007-07-17 Intel Corporation Micro-electromechanical structure resonator frequency adjustment using radiant energy trimming and laser/focused ion beam assisted deposition
EP2063470A1 (en) 2005-02-10 2009-05-27 Seiko Epson Corporation Piezoelectric vibrator, method for adjusting piezoelectric vibrator, piezoelectric actuator, timepiece, and electronic device
US7671518B2 (en) 2005-02-10 2010-03-02 Seiko Epson Corporation Piezoelectric vibrator, method for adjusting piezoelectric vibrator, piezoelectric actuator, timepiece, and electronic device
US8736144B2 (en) 2010-12-10 2014-05-27 Canon Kabushiki Kaisha Vibration type driving apparatus

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