JP4067044B2 - Oscillator and vibratory gyroscope - Google Patents

Description

面であり、他方の側面が
【数４】

面である。
【００３３】
本発明の振動子からの出力に基づいたゼロ点温度ドリフトは、振動子がどのような形成方法によって形成されていたとしても、前述したような振動片の横断面形状の影響を受ける。従って、本発明の振動片および振動子の形成方法は特に限定されず、ウエットエッチング法、ドライエッチング法の他、レーザー光線を使用した成形法でもよい。
【００３４】
ただし、実際の量産という観点からは、ウエットエッチング法が最も好ましい。この場合、エッチャントは限定されないが、以下のものが好ましい。エッチャントは、ふっ酸を含有していることが好ましく、ふっ酸水溶液か、あるいはふっ酸とフッ化アンモニウムとを任意の割合で混合した水溶液が好ましい。エッチャントの濃度は、４０重量％以下が好ましく、エッチャントの温度は、４０〜８０℃が好ましい。
【００３５】
本発明の振動型ジャイロスコープは、前述の振動子を備えている。この振動型ジャイロスコープは、更に駆動手段、検出手段を備えている。駆動手段、検出手段は、一般には振動子上に形成される電極の形態をしている。
【００３６】
第一の発明においては、一方の駆動振動片および他方の駆動振動片の厚さが、基部の厚さよりも小さい。これによって、前述した面外屈曲振動モードの固有共振周波数ｆｓを低下させ、温度ドリフトを低減することが可能である。
【００３７】
図６は、この実施形態に係る振動子１Ｂおよび振動型ジャイロスコープ２３を示す斜視図である。振動子１Ｂの各構成部分のうち、図１〜図３に示した構成部分には同じ符号をつけ、その説明を省略する。
【００３８】
振動子１Ｂにおいては、一方の駆動振動片１３Ａ、１３Ｂ、他方の駆動振動片１３Ｃ、１３Ｄの厚さが、基部６の厚さに比べて薄くなっている。本例では、各拡張部１４Ａ、１４Ｂ、１４Ｃ、１４Ｄの厚さも、駆動振動片の厚さと同様に、基部６の厚さよりも小さくなっている。支持部５Ａ、５Ｂ、検出振動片２Ａ、２Ｂ、検出振動片側の拡張部７Ａ、７Ｂの厚さは、基部６の厚さとほぼ同じである。このように駆動振動片の厚さを小さくすると、前述した面外屈曲振動モードの固有共振周波数ｆｓが若干低下する。２７は駆動電極であり、２８は検出電極である。
【００３９】
ｆｓを低下させるという観点からは、（駆動振動片の厚さ／基部の厚さ）は、０．９以下とすることが好ましく、０．８以下とすることが一層好ましい。しかし、駆動振動片の機械的強度の観点からは、（駆動振動片の厚さ／基部の厚さ）は、０．４以上とすることが好ましい。
【００４０】
第二の発明においては、一方の支持部の厚さおよび他方の支持部の厚さが基部の厚さよりも小さい。これによって、面外屈曲振動モードの固有共振周波数ｆｓを低下させ、温度ドリフトを低減することが可能である。
【００４１】
図７は、この実施形態に係る振動子１Ｃを示す斜視図である。振動子１Ｃにおいては、一方の支持部１５Ａ、他方の支持部１５Ｂの厚さが、基部６の厚さに比べて薄くなっている。本例では、各駆動振動片３Ａ〜３Ｄ、各拡張部４Ａ〜４Ｄ、検出振動片２Ａ、２Ｂ、検出振動片側の拡張部７Ａ、７Ｂの厚さは、基部６の厚さとほぼ同じである。このように各支持部の厚さを小さくすると、前述した面外屈曲振動モードの固有共振周波数ｆｓが低下する。
【００４２】
ｆｓを低下させるという観点からは、（支持部の厚さ／基部の厚さ）は、０．９以下とすることが好ましく、０．８以下とすることが一層好ましい。支持部の機械的強度の観点からは、（支持部の厚さ／基部の厚さ）は、０．４以上とすることが好ましい。
【００４３】
また、好適な実施形態においては、一方の駆動振動片および他方の駆動振動片の厚さを、拡張部の厚さよりも小さくする。これによって、面外屈曲振動モードの固有共振周波数ｆｓを低下させ、温度ドリフトを低減することが可能である。
【００４４】
図８は、この実施形態に係る振動子１Ｄを示す斜視図である。振動子１Ｄにおいては、一方の駆動振動片１３Ａ、１３Ｂ、他方の駆動振動片１３Ｃ、１３Ｄの厚さが、基部６の厚さおよび各拡張部４Ａ、４Ｂ、４Ｃ、４Ｄの厚さに比べて小さくなっている。本例では、各拡張部４Ａ〜４Ｄ、支持部５Ａ、５Ｂ、検出振動片２Ａ、２Ｂ、検出振動片側の拡張部７Ａ、７Ｂの厚さは、基部６の厚さとほぼ同じである。このように各駆動振動片の厚さを小さくし、拡張部４Ａ〜４Ｄの厚さを大きくすると、面外屈曲振動モードの固有共振周波数ｆｓが低下する。
【００４５】
ｆｓを低下させるという観点からは、（駆動振動片の厚さ／拡張部の厚さ）は、０．９以下とすることが好ましく、０．８以下とすることが一層好ましい。しかし、駆動振動片の機械的強度の観点からは、（駆動振動片の厚さ／拡張部の厚さ）は、０．４以上とすることが好ましい。
【００４６】
好適な実施形態においては、検出振動片が、所定平面に対して略平行な一対の主面を有しており、主面から振動子の厚さ方向に向かって凹部が設けられている。これによって、検出振動片が湾曲変形しにくくなり、面外屈曲振動モードの固有共振周波数ｆｓが低くなり、またその振幅が小さくなる。この結果温度ドリフトが低下する。
【００４７】
図９は、この実施形態に係る振動子１Ｅを示す斜視図である。振動子１Ｅにおいては、一方の駆動振動片１３Ａ、１３Ｂ、他方の駆動振動片１３Ｃ、１３Ｄの厚さが、基部６の厚さに比べて小さくなっている。また、各拡張部１４Ａ、１４Ｂ、１４Ｃ、１４Ｄの厚さが、基部６の厚さに比べて小さい。本例では、支持部５Ａ、５Ｂ、検出振動片２Ａ、２Ｂ、検出振動片側の拡張部７Ａ、７Ｂの厚さは、基部６の厚さとほぼ同じである。そして、検出振動片２Ａ、２Ｂが、Ｘ−Ｙ面に対して略平行な一対の主面２ａを有しており、主面２ａから振動子の厚さ方向に向かって凹部３０Ａ、３０Ｂが設けられている。
【００４８】
ｆｓを低下させるという観点からは、（凹部３０Ａ、３０Ｂの深さ／検出振動片２Ａ、２Ｂの厚さ）は、０．０５以上とすることが好ましく、０．１以上とすることが一層好ましい。
【００４９】
図１０の振動子１Ｆにおいては、一方の駆動振動片１３Ａ、１３Ｂ、他方の駆動振動片１３Ｃ、１３Ｄ、一方の支持部１５Ａ、他方の支持部１５Ｂの厚さが、基部６の厚さよりも小さい。各拡張部４Ａ、４Ｂ、４Ｃ、４Ｄ、７Ａ、７Ｂ、検出振動片２Ａ、２Ｂの厚さは、基部６の厚さとほぼ同じである。
【００５０】
好適な実施形態においては、一方の駆動振動片および他方の駆動振動片が、所定平面に対して略平行な一対の主面を有しており、主面から振動子の厚さ方向に向かって凹部が設けられている。図１１は、この実施形態に係る振動子１Ｇを示す斜視図である。振動子１Ｇにおいては、一方の支持部１５Ａ、他方の支持部１５Ｂの厚さが、基部６の厚さに比べて小さくなっている。また、各駆動振動片３Ａ〜３Ｄ、拡張部４Ａ〜４Ｄ、検出振動片２Ａ、２Ｂ、検出振動片側の拡張部７Ａ、７Ｂの厚さは、基部６の厚さとほぼ同じである。そして、駆動振動片３Ａ〜３Ｄは、Ｘ−Ｙ面に対して略平行な一対の主面３ａを有しており、主面３ａから振動子の厚さ方向に向かって凹部２０Ａ、２０Ｂ、２０Ｃ、２０Ｄが設けられている。各検出振動片２Ａ、２Ｂの主面２ａには凹部３０Ａ、３０Ｂが形成されている。
【００５１】
ｆｓを低下させるという観点からは、（凹部２０〜２０Ｄの深さ／駆動振動片３Ａ〜３Ｄの厚さ）は、０．０５以上とすることが好ましく、０．１以上とすることが一層好ましい。
【００５２】
図１２の振動子１Ｈにおいては、支持部１５Ａ、１５Ｂ、駆動振動片１３Ａ〜１３Ｄ、拡張部１４Ａ〜１４Ｄの厚さが、基部６の厚さよりも小さい。そして、検出振動片２Ａ、２Ｂ、検出振動片側の拡張部７Ａ、７Ｂの厚さは、基部６の厚さとほぼ同じである。また、各検出振動片２Ａ、２Ｂの主面２ａには凹部３０Ａ、３０Ｂが形成されている。
【００５３】
図１３の振動子１Ｊにおいては、各支持部１５Ａ、１５Ｂの厚さは基部６の厚さよりも小さい。そして、各駆動振動片３Ａ〜３Ｄ、各拡張部４Ａ〜４Ｄおよび７Ａ、７Ｂ、検出振動片２Ａ、２Ｂの厚さは、基部６の厚さとほぼ同じである。各駆動振動片３Ａ〜３Ｄには、主面３ａから凹んだ凹部２０Ａ、２０Ｂが形成されている。
【００５４】
図１４の振動子１Ｋにおいては、支持部１５Ａ、１５Ｂの厚さは基部６の厚さよりも小さい。駆動振動片３Ａ〜３Ｄ、拡張部４Ａ〜４Ｄ、７Ａ、７Ｂ、検出振動片２Ａ、２Ｂの厚さは、基部６の厚さとほぼ同じである。各検出振動片２Ａ、２Ｂには、主面２ａから凹んだ凹部２０Ａ、２０Ｂが形成されている。
【００５５】
図１５の振動子１Ｌにおいては、駆動振動片１３Ａ〜１３Ｄの厚さは、基部６の厚さよりも小さい。支持部５Ａ、５Ｂ、拡張部４Ａ〜４Ｄ、７Ａ、７Ｂ、検出振動片２Ａ、２Ｂの厚さは、基部６の厚さとほぼ同じである。各検出振動片２Ａ、２Ｂには凹部３０Ａ、３０Ｂが形成されている。
【００５６】
なお、上記の各振動子においては、駆動電極等の駆動手段や検出電極等の検出手段は図示省略しているが、むろん例えば図６に示すように駆動手段、検出手段を設けることで振動型ジャイロスコープを提供できる。
【００５７】
【実施例】
（例１）
図６に示す振動子１Ｂを製造した。具体的には、所定の厚さの水晶のＺ板のウエハーに、スパッタ法によって、厚さ２００オングストロームのクロム膜と、厚さ１０００オングストロームの金膜とを順番に形成した。ウエハーの両面にレジストをコーティングし、ホトマスクを設置し、露光した。
【００５８】
このウエハーを、ヨウ素とヨウ化カリウムとの水溶液に浸漬し、余分な金膜をエッチングによって除去し、更に硝酸セリウムアンモニウムと過塩素酸との水溶液にウエハーを浸漬し、余分なクロム膜をエッチングして除去した。温度８０℃の重フッ化アンモニウムに２０時間ウエハーを浸漬し、ウエハーをエッチングし、振動子１Ｂの外形を形成した。メタルマスクを使用して、厚さ２０００オングストロームのアルミニウム膜を電極膜２７、２８として形成した。
【００５９】
得られた振動子１Ｂの基部６の寸法は１．０ｍｍ×１．０ｍｍである。各駆動振動片１３Ａ〜１３Ｄの長さは２．１ｍｍである。各検出振動片２Ａ、２Ｂの長さは１．７ｍｍである。基部６、支持部５Ａ、５Ｂ、検出振動片２Ａ、２Ｂ、拡張部７Ａ、７Ｂの厚さは０．１ｍｍである。駆動振動片１３Ａ〜１３Ｄ、拡張部１４Ａ〜１４Ｄの厚さは０．０８ｍｍである。
【００６０】
振動子１Ｂの基部６の中央に０．１５ｍｍ×０．１５ｍｍの正方形の支持孔を形成し、この支持孔にシリコーン樹脂接着剤を注入して接着する。得られた各振動型ジャイロスコープについて、検出信号の測定値の−４０℃より＋８５℃の温度域におけるゼロ点信号の温度変動を測定する。
【００６１】
１０個の振動子を上記のようにして作製し、−４０℃より＋８５℃の温度域におけるゼロ点信号の最大値と最小値との差をゼロ点温度ドリフトとした。そして、ゼロ点温度ドリフトの平均値（ｎ＝１０）を算出し、表１に示した。また、ｆｓおよびｆｄを測定し、表１に示した。
【００６２】
【表１】

【００６３】
実施例１の振動子１Ｂにおいては、ｆｄ＝ｆｓ＋１７８２である。このように設計することで、温度ドリフト量を４．０に低減することができた。
【００６４】
（例２）
例１と同様にして、図７に示す振動子１Ｃを製造した。ただし、支持部１５Ａ、１５Ｂの厚さは０．０８ｍｍとした。この測定結果を表１に示す。
【００６５】
（例３）
例１と同様にして、図８に示す振動子１Ｄを製造した。ただし、駆動振動片１３Ａ〜１３Ｄの厚さは０．０８ｍｍとした。この測定結果を表１に示す。
【００６６】
（例４）
例１と同様にして、図９に示す振動子１Ｅを製造した。ただし、駆動振動片１３Ａ〜１３Ｄの厚さ、拡張部１４Ａ〜１４Ｄの厚さは０．０８ｍｍとした。凹部３０Ａ、３０Ｂの深さは０．０１ｍｍとした。この測定結果を表１に示す。
【００６７】
（例５）
例１と同様にして、図１６に示す形状の振動子２５Ａを作製した。この測定結果を表１に示す。
【００６８】
（例６）
例１と同様にして、図１７に示す形状の振動子２５Ｂを作製した。この測定結果を表１に示す。
【００６９】
（例７）
例１と同様にして、図１８に示す形状の振動子２５Ｃを作製した。この測定結果を表１に示す。
【００７０】
（例８）
例１と同様にして、図１９に示す形状の振動子２５Ｄを作製した。この測定結果を表１に示す。
【００７１】
これらの結果から分かるように、面外屈曲振動モードの存在、および面外屈曲振動モードの固有共振周波数ｆｓと駆動振動モードの固有共振周波数ｆｄとの関係が、温度ドリフト量に対して顕著な影響を与えている。従って、面外屈曲振動モードの固有共振周波数ｆｓが適切な範囲となるように振動子を設計することによって、温度ドリフトを低減可能である。
【００７２】
【発明の効果】
以上述べたように、本発明によれば、振動子のゼロ点温度ドリフトを低減できる。
【図面の簡単な説明】
【図１】振動子１Ａの面外屈曲振動モードを説明するための平面図である。
【図２】支持部１Ａの面外屈曲振動モードを説明するためのＹ軸側から見た図である。
【図３】振動子１Ａの面外屈曲振動モードの形状を示す斜視図である。
【図４】駆動振動片におけるＺ軸方向の振動成分の発生プロセスを説明するための模式図である。
【図５】周波数差（ｆｓ−ｆｄ）と温度ドリフトとの関係を示すグラフである。
【図６】振動子１Ｂの斜視図である。
【図７】振動子１Ｃの斜視図である。
【図８】振動子１Ｄの斜視図である。
【図９】振動子１Ｅの斜視図である。
【図１０】振動子１Ｆの斜視図である。
【図１１】振動子１Ｇの斜視図である。
【図１２】振動子１Ｈの斜視図である。
【図１３】振動子１Ｊの斜視図である。
【図１４】振動子１Ｋの斜視図である。
【図１５】振動子１Ｌの斜視図である。
【図１６】振動子２５Ａの斜視図である。
【図１７】振動子２５Ｂの斜視図である。
【図１８】振動子２５Ｃの斜視図である。
【図１９】振動子２５Ｄの斜視図である。
【符号の説明】
１Ａ、１Ｂ、１Ｃ、１Ｄ、１Ｅ、１Ｆ、１Ｇ、１Ｈ、１Ｊ、１Ｋ、１Ｌ、２５Ａ、２５Ｂ、２５Ｃ、２５Ｄ 振動子 ２Ａ、２Ｂ 検出振動片 ２ａ 検出振動片の主面 ３Ａ、３Ｂ 一方の駆動振動片
３Ｃ、３Ｄ 他方の駆動振動片 ３ａ 駆動振動片の主面
３ｂ 側面 ４Ａ、４Ｂ、４Ｃ、４Ｄ 駆動振動片側の拡張部 ５Ａ 一方の支持部 ５Ｂ 他方の支持部 ６ 基部 ７Ａ、７Ｂ 検出振動片側の拡張部 １０Ａ 基部６上の振動ノード １０Ｂ 一方の駆動振動片上の振動ノード １０Ｃ 他方の駆動振動片上の振動ノード １３Ａ、１３Ｂ、１３Ｃ、１３Ｄ 基部に比べて厚さの小さい駆動振動片 １４Ａ、１４Ｂ、１４Ｃ、１４Ｄ 基部に比べて厚さの小さい拡張部 １５Ａ 基部に比べて厚さの小さい一方の支持部
１５Ｂ 基部に比べて厚さの小さい他方の支持部 ２０Ａ、２０Ｂ、２０Ｃ、２０Ｄ 駆動振動片の主面からへこんだ凹部 ３０Ａ、３０Ｂ 検出振動片の主面からへこんだ凹部 Ａ、Ｂ 面外屈曲振動モード[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vibrator and a vibratory gyroscope.
[0002]
[Prior art]
Recently, it has been studied to install a vibrating gyroscope in an automobile and use it for controlling the direction of the body of the automobile. For example, when a vibration type gyroscope is used as a rotation speed sensor used in a vehicle control method of a vehicle body rotation speed feedback type of an automobile, the direction of the steering wheel itself is detected by the rotation angle of the steering wheel. At the same time, the rotational speed at which the vehicle body is actually rotating is detected by the vibration gyroscope. Then, the direction of the steering wheel is compared with the actual rotational speed of the vehicle body to obtain a difference, and based on this difference, correction is made to the wheel torque and the steering angle, thereby realizing stable vehicle body control.
[0003]
In in-vehicle applications, the operating temperature range of the vibration type gyroscope is extremely wide, and for example, it is required to operate stably in a temperature range of −40 ° C .− + 85 ° C. Even when the resonance frequency of the pair of bending vibration pieces is adjusted to a constant value at room temperature, fluctuations and variations in the resonance frequency may increase when the ambient temperature changes greatly to high and low temperatures. As a result, a so-called zero point temperature drift occurs.
[0004]
The present applicant disclosed in Patent Document 1 that the zero point temperature drift is suppressed by providing tapered portions at the bases of both side surfaces of the bending vibration piece.
[Patent Document 1]
JP 2001-12952 A
[0005]
[Problems to be solved by the invention]
However, when the present inventors have further studied, it has been found that there are new problems depending on the material of the vibrator. That is, as described in Japanese Patent Application Laid-Open No. 2001-12952, tapered portions are provided at the bases of both side surfaces of the bending vibration piece, and the shapes of these taper portions are substantially the same, so that the bending vibration piece It is considered that the symmetry of the vibration mode increases and the zero point temperature drift decreases. However, when the zero point temperature drift is measured for each manufactured vibrator, the value of the zero point temperature drift may vary for each vibrator. And the variation of the zero point temperature drift for every vibrator | oscillator becomes large, and the ratio of inferior goods may increase as a result.
[0006]
In particular, when the vibrator is downsized, the zero point temperature drift tends to increase, and the variation in the zero point temperature drift of each vibrator tends to increase.
[0007]
An object of the present invention is to reduce the zero point temperature drift of the vibrator and to reduce the variation of the zero point temperature drift of each vibrator.
[0008]
[Means for Solving the Problems]
The first invention includes a base, one support connected to the base, one drive vibration piece extending from the one support, the other support connected to the base, and the other support. The other drive vibration piece, and a detection vibration piece connected to the base, a vibrator formed along a predetermined plane,
In the driving vibration mode, the driving vibration piece performs in-plane bending vibration, and in the detection vibration mode, the detection vibration piece performs in-plane bending vibration, The vibrator vibrates in an out-of-plane bending vibration mode, and in this out-of-plane bending vibration mode, one support portion and the other support portion bend and vibrate in a reverse phase in a direction substantially perpendicular to a predetermined plane, One drive vibration piece and the other drive vibration piece each have a node, a plurality of the one drive vibration piece is provided on the one support portion, and the other drive vibration piece is provided on the other support portion. A plurality of pieces are provided, and each of the one drive vibration piece and the other drive vibration piece is provided with an extended portion, and the thickness of the one drive vibration piece and the other drive vibration piece is It is characterized by being smaller than the thickness of the base.
The second invention includes a base, one support connected to the base, one drive vibration piece extending from the one support, the other support connected to the base, and the other support. A vibrator having a drive vibration piece on the other side extending from the support portion and a plurality of detection vibration pieces connected to the base, and formed along a predetermined plane;
In the driving vibration mode, the driving vibration piece performs in-plane bending vibration, and in the detection vibration mode, the detection vibration piece performs in-plane bending vibration, The vibrator vibrates in an out-of-plane bending vibration mode, and in this out-of-plane bending vibration mode, the one support portion and the other support portion bend and vibrate in opposite phases in a direction substantially perpendicular to the predetermined plane. The base, the one drive vibration piece, and the other drive vibration piece each have a node, and the one support vibration portion is provided with a plurality of the one drive vibration piece, and the other support vibration piece is provided. A plurality of the other drive vibration pieces are provided in the part, and an extension part is provided in each of the one drive vibration piece and the other drive vibration piece, and the thickness of the one support part and the other drive vibration piece are provided. The thickness of the support part is smaller than the thickness of the base part.
[0009]
The present invention also relates to a vibratory gyroscope comprising the vibrator.
[0010]
The present inventor has discovered the existence of the above-described out-of-plane bending vibration mode as a result of examining the cause of the variation and increase in the zero point temperature drift of each vibrator. And it discovered that this out-of-plane bending vibration mode brings about temperature drift by combining with other vibration modes.
[0011]
Hereinafter, further description will be given with reference to the drawings. A vibrator 1A shown in FIG. 1 is a vibrator proposed by the present applicant (Japanese Patent Laid-Open No. 11-281372). A detailed description of the shape and operation of the vibrator 1A is omitted since it is described in detail in Japanese Patent Application Laid-Open No. 11-281372.
[0012]
The vibrator 1A includes a base 6, one support 5A protruding from the base 6, one drive vibrating piece 3A, 3B extending from the one support 5A, the other support 5B protruding from the base 6, and the other The other drive vibration pieces 3C and 3D extending from the support portion 5B and the detection vibration pieces 2A and 2B extending from the base portion 6 are provided, which are formed along a predetermined plane (XY plane). In the drive vibration mode, each of the drive vibration pieces 3A to 3D is flexibly vibrated in the XY plane around the root to the support portion (arrow C). When the vibrator is rotated around the Z axis in this state, each of the support portions 5A and 5B bends and vibrates in the plane around the root to the base portion 6 (arrow D). In response to this, each of the detection vibrating pieces 2A, 2B bends and vibrates in the plane as indicated by an arrow E with the root to the base 6 as the center. The in-plane bending vibration as indicated by the arrow E is detected by detection means provided on the detection vibrating pieces 2A and 2B, and a signal corresponding to the rotational angular velocity is obtained.
[0013]
Here, this inventor discovered the out-of-plane bending vibration mode of a form as shown in FIGS. 1-3. However, FIG. 1 shows a plan view of the vibrator 1A and a schematic form of its AA cross section and BB cross section, and FIG. 2 shows a front view when the vibrator 1A is viewed from the Y-axis direction. FIG. 3 shows the form of the vibrator 1A at a certain point of time in the out-of-plane bending vibration mode.
[0014]
In this mode, one support portion 5A and the other support portion 5B flexurally vibrate in a direction substantially perpendicular to the predetermined plane (XY plane) (Z-axis direction) (see arrows A and B). . At any moment, the displacement of the support portion 5A relative to the XY plane is opposite to the displacement of the support portion 5B. That is, the out-of-plane bending vibration of the support portion 5A as indicated by the arrow A and the out-of-plane bending vibration of the support portion 5B as indicated by the arrow B are in opposite phases. In this out-of-plane bending vibration mode, the base has a vibration node (node) 10A, one drive vibration piece 3A, 3B has a node 10B, and the other drive vibration piece 3C, 3D. A node 10C is provided on the top.
[0015]
That is, in this mode, the entire vibrator 1A vibrates like a wave from the XY plane toward the Z-axis direction.
[0016]
When the vibrator exhibits such an out-of-plane bending vibration mode, the inventor can reduce temperature drift to a minimum by adjusting the natural resonance frequency and amplitude of the out-of-plane bending vibration mode. As a result, they have reached the present invention. In other words, the discovery and detection of such an out-of-plane bending vibration mode has the significance that it has become possible to take effective measures against temperature drift.
[0017]
It is considered that the out-of-plane bending vibration mode as described above does not appear if the vibrator is formed to be completely plane-symmetric with respect to the XY plane. However, in the actual process of forming a vibrator, the form of the vibrator is not symmetric with respect to the XY plane due to uncertain factors different from the design in the figure. Is expressed.
[0018]
The following causes are typically considered. In order to form the outer contour of the resonator element, for example, a wafer made of a piezoelectric single crystal is etched. At the stage of the etching process, for example, a photoresist is applied to both the front surface side and the back surface side of the wafer, a photomask is placed thereon, and the front side photomask and the back side photomask are aligned. Then, the photoresist is exposed and cured, the photomask is removed, and the photoresist is patterned. Then, the wafer is etched, and a contour corresponding to the photoresist pattern is formed on the wafer.
[0019]
Here, when a photomask is installed on both the front surface side and the back surface side of the wafer for alignment, a slight positional deviation may occur between both masks. In this case, as shown in FIG. 4, the cross-sectional contour of the drive vibrating piece 3 is a parallelogram (see the broken line). 3a is the front surface and back surface of the drive vibration piece, and 3b is a side surface. When the drive vibrating piece 3 is driven in the arrow C direction in this state, an unnecessary vibration component in the Z direction is generated.
[0020]
As described above, it is considered that the out-of-plane bending vibration mode as described above is generated as a result of the cross-sectional contours of the driving vibration piece and the detection vibration piece not being rectangular and being distorted.
[0021]
Then, it is considered that an unnecessary vibration component in the Z direction when the driving vibration piece is driven is combined with the out-of-plane bending vibration mode to generate a temperature drift.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, more preferred embodiments will be described.
“The vibrator is formed along a predetermined plane” does not mean a geometrically strict meaning, and a manufacturing error is allowed. In a preferred embodiment, the entire vibrator has a flat plate shape. The support part and the detection vibration piece are connected to the base when the support part and the detection vibration piece protrude directly from the base and when the support part and the detection vibration piece are connected to the base via another connection piece. Including connected cases. Preferably, the support portion protrudes directly from the base portion, or the detection vibration piece protrudes directly from the base portion.
[0023]
The present invention In FIG. 1, a plurality of one drive vibration piece are provided on one support portion, and a plurality of the other drive vibration pieces are provided on the other support portion. As shown in FIG. 1, a pair of drive vibration pieces can be provided for each support portion, but three or more drive vibration pieces may be provided.
[0024]
In a preferred embodiment, a plurality of detection vibrating pieces are provided. In this case, a more accurate measurement value can be obtained by mathematically processing (for example, adding or subtracting) the output signal from each detection vibrating piece.
[0025]
The present invention In FIG. 2, one of the drive vibration pieces and the other of the drive vibration pieces are provided with expansion portions.
[0026]
In a preferred embodiment, the natural resonance frequency fd (Hz) of the drive vibration mode excited by one drive vibration piece and the other drive vibration piece and the natural resonance frequency fs (Hz) of the out-of-plane bending vibration mode are obtained. Satisfy the following relationship.
fs + 4500 ≧ fd ≧ fs + 1500
(Alternatively, −1500 ≧ fs−fd ≧ −4500)
[0027]
As described above, when the out-of-plane vibration of the driving vibration piece (vibration in the Z-axis direction) and the out-of-plane bending vibration mode are combined to cause temperature drift, the natural resonance frequency fd of the driving vibration mode is generated. It has been found that it is effective to increase the frequency to a certain degree or more than the natural resonance frequency fs of the out-of-plane bending vibration mode. In a normal design, the natural resonance frequency fs of the out-of-plane bending vibration mode is higher than fd (fd <fs), and thus the temperature drift tends to increase.
[0028]
On the other hand, for example, as shown in FIG. 5, the temperature drift can be remarkably reduced by sufficiently reducing the natural resonance frequency fs of the out-of-plane bending vibration mode.
[0029]
Here, the difference between fd and fs is preferably 1500 Hz or more, and more preferably 2500 Hz or more. However, when the difference between fd and fs becomes too large, the temperature drift tends to rise again. For this reason, the difference between fd and fs is preferably 4500 Hz or less, and more preferably 3500 Hz or less.
[0030]
In a preferred embodiment, the vibrator is made of a piezoelectric single crystal. Examples of piezoelectric single crystals include quartz and LiNbO. ₃ LiTaO ₃ Lithium niobate-lithium tantalate solid solution (Li (Nb, Ta) O ₃ ) Single crystals, lithium borate single crystals, and langasite single crystals.
[0031]
Particularly preferably, the vibrator is made of a piezoelectric single crystal having an a-axis that is rotationally symmetrical three times in a predetermined plane and a c-axis in a direction perpendicular to the predetermined plane. This is particularly preferably quartz.
[0032]
In a preferred embodiment, one side is
[Equation 3]

The other side
[Expression 4]

Surface.
[0033]
The zero point temperature drift based on the output from the vibrator of the present invention is affected by the cross-sectional shape of the vibrator element as described above, regardless of the formation method of the vibrator. Therefore, the method for forming the resonator element and the vibrator of the present invention is not particularly limited, and a molding method using a laser beam may be used in addition to the wet etching method and the dry etching method.
[0034]
However, the wet etching method is most preferable from the viewpoint of actual mass production. In this case, the etchant is not limited, but the following is preferable. The etchant preferably contains hydrofluoric acid, and is preferably an aqueous hydrofluoric acid solution or an aqueous solution in which hydrofluoric acid and ammonium fluoride are mixed in an arbitrary ratio. The concentration of the etchant is preferably 40% by weight or less, and the temperature of the etchant is preferably 40 to 80 ° C.
[0035]
The vibrating gyroscope of the present invention includes the above-described vibrator. This vibratory gyroscope further includes a drive unit and a detection unit. The drive means and the detection means are generally in the form of electrodes formed on the vibrator.
[0036]
1st invention The thickness of one drive vibrating piece and the other drive vibrating piece is smaller than the thickness of the base. As a result, it is possible to reduce the natural resonance frequency fs of the above-described out-of-plane bending vibration mode and reduce the temperature drift.
[0037]
FIG. 6 is a perspective view showing the vibrator 1B and the vibrating gyroscope 23 according to this embodiment. Among the constituent parts of the vibrator 1B, the same reference numerals are given to the constituent parts shown in FIGS. 1 to 3, and the description thereof is omitted.
[0038]
In the vibrator 1 </ b> B, the thickness of one drive vibrating piece 13 </ b> A, 13 </ b> B and the other drive vibrating piece 13 </ b> C, 13 </ b> D is thinner than the thickness of the base 6. In this example, the thickness of each of the extended portions 14A, 14B, 14C, and 14D is also smaller than the thickness of the base portion 6 as is the thickness of the drive vibrating piece. The thicknesses of the support portions 5A and 5B, the detection vibration pieces 2A and 2B, and the extension portions 7A and 7B on the detection vibration piece side are substantially the same as the thickness of the base portion 6. When the thickness of the drive vibration piece is reduced in this way, the natural resonance frequency fs of the out-of-plane bending vibration mode described above slightly decreases. Reference numeral 27 denotes a drive electrode, and reference numeral 28 denotes a detection electrode.
[0039]
From the viewpoint of reducing fs, (the thickness of the driving vibration piece / the thickness of the base) is preferably 0.9 or less, and more preferably 0.8 or less. However, from the viewpoint of the mechanical strength of the driving vibration piece, (the thickness of the driving vibration piece / the thickness of the base) is preferably set to 0.4 or more.
[0040]
Second invention The thickness of one support part and the thickness of the other support part are smaller than the thickness of the base part. As a result, the natural resonance frequency fs of the out-of-plane bending vibration mode can be lowered, and the temperature drift can be reduced.
[0041]
FIG. 7 is a perspective view showing a vibrator 1C according to this embodiment. In the vibrator 1 </ b> C, the thickness of one support portion 15 </ b> A and the other support portion 15 </ b> B is thinner than the thickness of the base portion 6. In this example, the thicknesses of the drive vibration pieces 3A to 3D, the extension portions 4A to 4D, the detection vibration pieces 2A and 2B, and the extension portions 7A and 7B on the detection vibration piece side are substantially the same as the thickness of the base portion 6. Thus, when the thickness of each support portion is reduced, the natural resonance frequency fs of the out-of-plane bending vibration mode described above is lowered.
[0042]
From the viewpoint of reducing fs, (the thickness of the support portion / the thickness of the base portion) is preferably 0.9 or less, and more preferably 0.8 or less. From the viewpoint of the mechanical strength of the support portion, (the thickness of the support portion / the thickness of the base portion) is preferably 0.4 or more.
[0043]
In a preferred embodiment, the thickness of one drive vibration piece and the other drive vibration piece is made smaller than the thickness of the extension portion. As a result, the natural resonance frequency fs of the out-of-plane bending vibration mode can be lowered, and the temperature drift can be reduced.
[0044]
FIG. 8 is a perspective view showing a vibrator 1D according to this embodiment. In the vibrator 1D, the thickness of one drive vibrating piece 13A, 13B and the other drive vibrating piece 13C, 13D is larger than the thickness of the base 6 and the thickness of each of the extended portions 4A, 4B, 4C, 4D. It is getting smaller. In this example, the thicknesses of the expansion portions 4A to 4D, the support portions 5A and 5B, the detection vibration pieces 2A and 2B, and the expansion portions 7A and 7B on the detection vibration piece side are substantially the same as the thickness of the base portion 6. Thus, when the thickness of each drive vibration piece is reduced and the thicknesses of the expansion portions 4A to 4D are increased, the natural resonance frequency fs of the out-of-plane bending vibration mode is lowered.
[0045]
From the viewpoint of reducing fs, (the thickness of the drive vibration piece / the thickness of the extension portion) is preferably 0.9 or less, and more preferably 0.8 or less. However, from the viewpoint of the mechanical strength of the driving vibration piece, (thickness of the driving vibration piece / thickness of the extended portion) is preferably set to 0.4 or more.
[0046]
In a preferred embodiment, the detection vibrating piece has a pair of main surfaces substantially parallel to a predetermined plane, and a recess is provided from the main surface in the thickness direction of the vibrator. As a result, the detection vibrating piece is less likely to be bent and deformed, the natural resonance frequency fs of the out-of-plane bending vibration mode is lowered, and the amplitude is reduced. As a result, temperature drift is reduced.
[0047]
FIG. 9 is a perspective view showing a vibrator 1E according to this embodiment. In the vibrator 1 </ b> E, the thickness of one drive vibrating piece 13 </ b> A, 13 </ b> B and the other drive vibrating piece 13 </ b> C, 13 </ b> D is smaller than the thickness of the base 6. Further, the thickness of each of the extended portions 14A, 14B, 14C, and 14D is smaller than the thickness of the base portion 6. In this example, the thicknesses of the support portions 5A and 5B, the detection vibration pieces 2A and 2B, and the expansion portions 7A and 7B on the detection vibration piece side are substantially the same as the thickness of the base portion 6. The detection vibrating reeds 2A and 2B have a pair of main surfaces 2a substantially parallel to the XY plane, and concave portions 30A and 30B are provided from the main surface 2a in the thickness direction of the vibrator. It has been.
[0048]
From the viewpoint of reducing fs, (the depth of the recesses 30A and 30B / the thickness of the detection vibrating pieces 2A and 2B) is preferably 0.05 or more, and more preferably 0.1 or more. .
[0049]
In the vibrator 1F of FIG. 10, the thickness of one of the drive vibration pieces 13A and 13B, the other drive vibration piece 13C and 13D, the one support portion 15A, and the other support portion 15B is smaller than the thickness of the base portion 6. . The thicknesses of the extended portions 4A, 4B, 4C, 4D, 7A and 7B, and the detection vibrating pieces 2A and 2B are substantially the same as the thickness of the base portion 6.
[0050]
In a preferred embodiment, one drive vibration piece and the other drive vibration piece have a pair of main surfaces substantially parallel to a predetermined plane, and from the main surface toward the thickness direction of the vibrator. A recess is provided. FIG. 11 is a perspective view showing a vibrator 1G according to this embodiment. In the vibrator 1G, the thickness of one support portion 15A and the other support portion 15B is smaller than the thickness of the base portion 6. Further, the thicknesses of the drive vibration pieces 3A to 3D, the extension portions 4A to 4D, the detection vibration pieces 2A and 2B, and the extension portions 7A and 7B on the detection vibration piece side are substantially the same as the thickness of the base portion 6. The drive vibration pieces 3A to 3D have a pair of main surfaces 3a substantially parallel to the XY plane, and the recesses 20A, 20B, and 20C from the main surface 3a toward the thickness direction of the vibrator. , 20D are provided. Concave portions 30A and 30B are formed in the main surface 2a of each detection vibrating piece 2A and 2B.
[0051]
From the viewpoint of reducing fs, (the depth of the recesses 20 to 20D / the thickness of the driving vibration pieces 3A to 3D) is preferably 0.05 or more, and more preferably 0.1 or more. .
[0052]
In the vibrator 1 </ b> H of FIG. 12, the thicknesses of the support portions 15 </ b> A and 15 </ b> B, the drive vibration pieces 13 </ b> A to 13 </ b> D, and the extension portions 14 </ b> A to 14 </ b> D are smaller than the thickness of the base portion 6. The thicknesses of the detection vibration pieces 2A and 2B and the expansion portions 7A and 7B on the detection vibration piece side are substantially the same as the thickness of the base portion 6. In addition, recesses 30A and 30B are formed in the main surface 2a of each detection vibrating piece 2A and 2B.
[0053]
In the vibrator 1 </ b> J of FIG. 13, the thicknesses of the support portions 15 </ b> A and 15 </ b> B are smaller than the thickness of the base portion 6. The thicknesses of the drive vibration pieces 3A to 3D, the expansion portions 4A to 4D and 7A and 7B, and the detection vibration pieces 2A and 2B are substantially the same as the thickness of the base portion 6. Recesses 20A and 20B that are recessed from the main surface 3a are formed in each of the drive vibration pieces 3A to 3D.
[0054]
In the vibrator 1K of FIG. 14, the thickness of the support portions 15A and 15B is smaller than the thickness of the base portion 6. The thicknesses of the drive vibration pieces 3A to 3D, the extension portions 4A to 4D, 7A and 7B, and the detection vibration pieces 2A and 2B are substantially the same as the thickness of the base portion 6. Recesses 20A and 20B that are recessed from the main surface 2a are formed in the respective detection vibrating pieces 2A and 2B.
[0055]
In the vibrator 1 </ b> L of FIG. 15, the thickness of the drive vibration pieces 13 </ b> A to 13 </ b> D is smaller than the thickness of the base portion 6. The thicknesses of the support portions 5A and 5B, the expansion portions 4A to 4D, 7A and 7B, and the detection vibrating pieces 2A and 2B are substantially the same as the thickness of the base portion 6. Recesses 30A and 30B are formed in each of the detection vibrating pieces 2A and 2B.
[0056]
In each of the above vibrators, driving means such as driving electrodes and detecting means such as detecting electrodes are not shown, but of course, for example, by providing driving means and detecting means as shown in FIG. A gyroscope can be provided.
[0057]
【Example】
(Example 1)
A vibrator 1B shown in FIG. 6 was manufactured. Specifically, a chromium film having a thickness of 200 angstroms and a gold film having a thickness of 1000 angstroms were successively formed on a quartz Z-plate wafer having a predetermined thickness by sputtering. A resist was coated on both sides of the wafer, and a photomask was placed and exposed.
[0058]
This wafer is immersed in an aqueous solution of iodine and potassium iodide, and the excess gold film is removed by etching. Further, the wafer is immersed in an aqueous solution of cerium ammonium nitrate and perchloric acid, and the excess chromium film is etched. Removed. The wafer was immersed in ammonium bifluoride at a temperature of 80 ° C. for 20 hours, and the wafer was etched to form the outer shape of the vibrator 1B. Aluminum films having a thickness of 2000 angstroms were formed as electrode films 27 and 28 using a metal mask.
[0059]
The dimension of the base 6 of the obtained vibrator 1B is 1.0 mm × 1.0 mm. The length of each drive vibrating piece 13A to 13D is 2.1 mm. The length of each detection vibrating piece 2A, 2B is 1.7 mm. The thickness of the base portion 6, the support portions 5A and 5B, the detection vibrating pieces 2A and 2B, and the expansion portions 7A and 7B is 0.1 mm. The thickness of the drive vibrating pieces 13A to 13D and the extended portions 14A to 14D is 0.08 mm.
[0060]
A square support hole of 0.15 mm × 0.15 mm is formed in the center of the base 6 of the vibrator 1B, and a silicone resin adhesive is injected into the support hole and bonded. For each obtained vibration gyroscope, the temperature fluctuation of the zero point signal in the temperature range from −40 ° C. to + 85 ° C. of the measured value of the detection signal is measured.
[0061]
Ten vibrators were produced as described above, and the difference between the maximum value and the minimum value of the zero point signal in the temperature range from −40 ° C. to + 85 ° C. was defined as the zero point temperature drift. And the average value (n = 10) of the zero point temperature drift was calculated and shown in Table 1. Further, fs and fd were measured and shown in Table 1.
[0062]
[Table 1]

[0063]
In the vibrator 1B of the first embodiment, fd = fs + 1782. By designing in this way, the amount of temperature drift could be reduced to 4.0.
[0064]
(Example 2)
In the same manner as in Example 1, a vibrator 1C shown in FIG. However, the thickness of the support portions 15A and 15B was 0.08 mm. The measurement results are shown in Table 1.
[0065]
(Example 3)
In the same manner as in Example 1, the vibrator 1D shown in FIG. However, the thickness of the drive vibration pieces 13A to 13D was 0.08 mm. The measurement results are shown in Table 1.
[0066]
(Example 4)
In the same manner as in Example 1, a vibrator 1E shown in FIG. However, the thickness of the drive vibration pieces 13A to 13D and the thickness of the expansion portions 14A to 14D were set to 0.08 mm. The depth of the recesses 30A and 30B was set to 0.01 mm. The measurement results are shown in Table 1.
[0067]
(Example 5)
In the same manner as in Example 1, a vibrator 25A having the shape shown in FIG. The measurement results are shown in Table 1.
[0068]
(Example 6)
In the same manner as in Example 1, a vibrator 25B having the shape shown in FIG. The measurement results are shown in Table 1.
[0069]
(Example 7)
In the same manner as in Example 1, a vibrator 25C having the shape shown in FIG. The measurement results are shown in Table 1.
[0070]
(Example 8)
In the same manner as in Example 1, a vibrator 25D having the shape shown in FIG. 19 was produced. The measurement results are shown in Table 1.
[0071]
As can be seen from these results, the presence of the out-of-plane bending vibration mode and the relationship between the natural resonance frequency fs of the out-of-plane bending vibration mode and the natural resonance frequency fd of the driving vibration mode have a significant effect on the temperature drift amount. Is given. Therefore, the temperature drift can be reduced by designing the vibrator so that the natural resonance frequency fs of the out-of-plane bending vibration mode is within an appropriate range.
[0072]
【The invention's effect】
As described above, according to the present invention, the zero point temperature drift of the vibrator can be reduced.
[Brief description of the drawings]
FIG. 1 is a plan view for explaining an out-of-plane bending vibration mode of a vibrator 1A.
FIG. 2 is a view seen from the Y-axis side for explaining an out-of-plane bending vibration mode of the support portion 1A.
FIG. 3 is a perspective view showing the shape of an out-of-plane bending vibration mode of a vibrator 1A.
FIG. 4 is a schematic diagram for explaining a generation process of a vibration component in a Z-axis direction in a drive vibration piece.
FIG. 5 is a graph showing a relationship between a frequency difference (fs−fd) and a temperature drift.
FIG. 6 is a perspective view of a vibrator 1B.
FIG. 7 is a perspective view of a vibrator 1C.
FIG. 8 is a perspective view of a vibrator 1D.
FIG. 9 is a perspective view of a vibrator 1E.
FIG. 10 is a perspective view of a vibrator 1F.
FIG. 11 is a perspective view of a vibrator 1G.
FIG. 12 is a perspective view of a vibrator 1H.
FIG. 13 is a perspective view of a vibrator 1J.
FIG. 14 is a perspective view of a vibrator 1K.
FIG. 15 is a perspective view of a vibrator 1L.
FIG. 16 is a perspective view of a vibrator 25A.
FIG. 17 is a perspective view of a vibrator 25B.
FIG. 18 is a perspective view of a vibrator 25C.
FIG. 19 is a perspective view of a vibrator 25D.
[Explanation of symbols]
1A, 1B, 1C, 1D, 1E, 1F, 1G, 1H, 1J, 1K, 1L, 25A, 25B, 25C, 25D Vibrator 2A, 2B Detection vibration piece 2a Main surface of detection vibration piece 3A, 3B One drive Vibrating piece
3C, 3D The other drive vibration piece 3a The main surface of the drive vibration piece
3b Side face 4A, 4B, 4C, 4D Drive vibration piece side expansion part 5A One support part 5B Other support part 6 Base part 7A, 7B Detection vibration piece side extension part 10A Vibration node on base part 6B On one drive vibration piece Vibration node 10C Vibration node 13A, 13B, 13C, 13D on the other drive vibration piece Drive vibration piece 14A, 14B, 14C, 14D having a smaller thickness than the base part Extension part 15A having a smaller thickness than the base part 15A Compared to the base part One support part with small thickness
15B The other support portion 20A, 20B, 20C, 20D having a thickness smaller than that of the base portion Recessed portion 30A, 30B recessed from the main surface of the driving vibration piece Recessed portion A, B bending vibration from the main surface of the detection vibration piece mode

Claims (9)

A base, one support connected to the base, one drive vibration piece extending from the one support, the other support connected to the base, and the other support A vibrator having a drive vibration piece on the other side and a plurality of detection vibration pieces connected to the base, and formed along a predetermined plane;
In the driving vibration mode, the driving vibration piece vibrates in the plane, in the detection vibration mode, the detection vibration piece vibrates in the plane, and the vibrator vibrates in the out-of-plane bending vibration mode. The one support portion and the other support portion bend and vibrate in opposite phases in a direction substantially perpendicular to the predetermined plane, and the base, the one drive vibration piece, and the other drive vibration piece respectively A plurality of the one drive vibration piece is provided on the one support portion, and a plurality of the other drive vibration pieces are provided on the other support portion. An extension portion is provided in each of the piece and the other drive vibration piece, and the vibration is characterized in that the thickness of the one drive vibration piece and the other drive vibration piece is smaller than the thickness of the base portion. Child A base, one support connected to the base, one drive vibration piece extending from the one support, the other support connected to the base, and the other support A vibrator having a drive vibration piece on the other side and a plurality of detection vibration pieces connected to the base, and formed along a predetermined plane;
In the driving vibration mode, the driving vibration piece vibrates in the plane, in the detection vibration mode, the detection vibration piece vibrates in the plane, and the vibrator vibrates in the out-of-plane bending vibration mode. The one support portion and the other support portion bend and vibrate in opposite phases in a direction substantially perpendicular to the predetermined plane, and the base, the one drive vibration piece, and the other drive vibration piece respectively A plurality of the one drive vibration piece is provided on the one support portion, and a plurality of the other drive vibration pieces are provided on the other support portion. An extension portion is provided in each of the piece and the other drive vibration piece, and the thickness of the one support portion and the thickness of the other support portion are smaller than the thickness of the base portion. Child.   3. The vibrator according to claim 1, wherein thicknesses of the one driving vibration piece and the other driving vibration piece are smaller than a thickness of the extension portion. 4.   The one drive vibration piece and the other drive vibration piece have a pair of main surfaces substantially parallel to the predetermined plane, and a concave portion is formed from the main surface toward the thickness direction of the vibrator. The vibrator according to claim 1, wherein the vibrator is provided.   The vibrator according to any one of claims 1 to 4, wherein the vibrator is made of a piezoelectric single crystal.   The vibrator according to claim 1, wherein the vibrator is formed by etching. The one drive vibration piece and the other drive vibration piece have a pair of main surfaces substantially parallel to the predetermined plane and a pair of side surfaces substantially perpendicular to the predetermined plane. Of the side surfaces, one of the side surfaces is

The other side is

The vibrator according to claim 1, wherein the vibrator is a surface.   A vibratory gyroscope comprising the vibrator according to any one of claims 1 to 7. 9. The vibrating gyroscope according to claim 8, wherein a detection rotation axis is substantially perpendicular to the predetermined plane.

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