JP3843839B2

JP3843839B2 - Angular velocity sensor

Info

Publication number: JP3843839B2
Application number: JP2001400138A
Authority: JP
Inventors: 正数畑中; 幸二山本; 昌良村上
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2001-12-28
Filing date: 2001-12-28
Publication date: 2006-11-08
Anticipated expiration: 2021-12-28
Also published as: JP2003194544A

Description

【０００１】
【発明の属する技術分野】
本発明は、航空機・車両などの移動体の姿勢制御やナビゲーションシステム等に用いられる角速度センサに関するものである。
【０００２】
【従来の技術】
従来のこの種の角速度センサとしては特開平１１−５１６５８号公報に開示されたものが知られている。
【０００３】
以下、従来の角速度センサについて、図面を参照しながら説明する。
【０００４】
図７は従来の角速度センサの斜視図である。
【０００５】
図７において、１は音叉で、一対の柱部２と、この柱部２の端部を接続する固着部３とにより構成されている。そして、前記音叉１における一対の柱部２のそれぞれの上面には第１の駆動電極４が設けられるとともに、この第１の駆動電極４と同一面上に第２の駆動電極５を設けている。そしてまた、前記音叉１は、一対の柱部２における第１の駆動電極４および第２の駆動電極５を設けた面と同一面上にモニター電極６および分極検知電極７を設けるとともに、一対の柱部２のそれぞれの外側面には検出電極８を設けている。９は支持部で、前記音叉１における固着部３を支持している。１０は基台で、上面に凸部１１を設けるとともに、この凸部１１の上面に支持部９の下面を固着している。また、前記基台１０には上面から下面にわたって絶縁物１２を介して挿通する端子１３を設けており、そしてこの端子１３は、音叉１における第１の駆動電極４、第２の駆動電極５、モニター電極６および検出電極８にワイヤー線１４により電気的に接続されている。
【０００６】
以上のように構成されている従来の角速度センサについて、次に、その動作を説明する。
【０００７】
音叉１における第１の駆動電極４および第２の駆動電極５に交流電圧を印加することにより音叉１が駆動方向の固有振動数で駆動方向に速度Ｖで屈曲振動する。この状態において、音叉１が音叉１の中心軸回りに角速度ωで回転すると、音叉１における一対の柱部２にＦ＝２ｍＶ・ωのコリオリ力が発生する。このコリオリ力により検出電極８に発生する電荷を増幅し、出力電圧として外部コンピュータ等（図示せず）で測定することにより角速度を検出していた。
【０００８】
ここで、音叉１に強い振動が長時間にわたって加わることにより、第１の駆動電極４および第２の駆動電極５と基台１０における端子１３とを結ぶワイヤー線１４が外れた場合、従来の角速度センサにおいては、音叉１が振動しなくなるため、ワイヤー線１４の断線を検知することができるものであった。
【０００９】
【発明が解決しようとする課題】
しかしながら上記従来の構成においては、角速度センサに強い振動が加わることにより、音叉１における一方の検出電極８と端子１３とを結ぶワイヤー線１４が外れてしまうと、出力電圧が半減するため、あたかも角速度センサに半分の角速度が加わっているように誤認してしまうこととなり、その結果、ワイヤー線１４の断線を検知することができないため、誤まった角速度を検出してしまうという課題を有していた。
【００１０】
本発明は上記従来の課題を解決するもので、誤った角速度を検出するということがなく、断線を確実に検知することができる角速度センサを提供することを目的とするものである。
【００１１】
【課題を解決するための手段】
上記目的を達成するために、本発明は以下の構成を有するものである。
【００１２】
本発明の請求項１に記載の発明は、特に、一対の駆動電極および一対の検出電極を設けた振動体と、この振動体における一対の駆動電極および一対の検出電極を延出させて形成した一対の駆動電極延出部および一対の検出電極延出部を有する固着部とからなる音叉と、この音叉における固着部を固着するとともに少なくとも４つの端子を挿通させた基台と、この基台における端子と前記音叉の固着部における駆動電極延出部あるいは検出電極延出部とを電気的に接続するワイヤー線とを備え、前記音叉の振動体における駆動電極と検出電極との間隙を略同一にすることにより、駆動電極と両隣の検出電極との間に生じる静電容量を略同一にするとともに、音叉における固着部に駆動電極を延出させて形成した駆動電極延出部の両隣に、この駆動電極延出部との間隙が略同一になるように検出電極延出部を延出形成することにより、駆動電極延出部と両隣の検出電極延出部との間に生じる静電容量を略同一にしたもので、この構成によれば、角速度センサに角速度を付与しない状態において、音叉における一方の検出電極と端子とを結ぶワイヤー線が外れてしまうと、駆動電極から発生する高周波成分によるクロストークノイズは他方の検出電極のみに誘電体よりなる振動体を伝わって到達することになり、その結果、クロストークノイズにより一対の検出電極に発生する電荷が互いに打ち消しあうことはなくなるため、常時、他方の検出電極に電圧が発生することになり、これにより、一方の検出電極と端子とを結ぶワイヤー線の断線を検知することができるという作用効果を有するとともに、クロストークノイズにより発生する電荷が駆動電極延出部から誘電体よりなる固着部を伝わって検出電極延出部に到達することになるため、音叉における一方の検出電極延出部と電気的に接続された検出電極と端子とを結ぶワイヤー線が外れてしまうと、駆動電極延出部から発生する高周波成分によるクロストークノイズが他方の検出電極延出部のみに誘電体よりなる固着部を伝わって到達することになり、その結果、クロストークノイズにより一対の検出電極延出部に発生する電荷が互いに打ち消しあうことはなくなるため、常時、他方の検出電極延出部に発生する電圧は大となり、これにより、一方の検出電極と端子とを結ぶワイヤー線の断線を確実に検知することができるという作用効果を有するものである。
【００１３】
本発明の請求項２に記載の発明は、特に、音叉における固着部に一方の駆動電極を延出させて形成した一方の駆動電極延出部に一方の検出電極延出部を沿わせるとともに、前記固着部に他方の駆動電極を延出させて形成した他方の駆動電極延出部に他方の検出電極延出部を沿わせ、かつ前記一方の駆動電極延出部に一方の検出電極延出部を沿わせる距離およびそれらの間隙と、他方の駆動電極延出部に他方の検出電極延出部を沿わせる距離およびそれらの間隙とを略同一にすることにより、一方の駆動電極延出部と一方の検出電極延出部との間に生じる静電容量および他方の駆動電極延出部と他方の検出電極延出部との間に生じる静電容量を互いに略同一にしたもので、この構成によれば、駆動電極延出部に検出電極延出部が沿う距離がさらに長くなるため、クロストークノイズが検出電極延出部に到達することにより発生する電荷が大となり、その結果、一方の検出電極と端子とを結ぶワイヤー線の断線を、さらに確実に検知することができるという作用効果を有するものである。
【００１４】
本発明の請求項３に記載の発明は、特に、駆動電極延出部を枝部を有する櫛形状に形成するとともに、検出電極延出部を枝部を有する櫛形状に形成し、さらに前記駆動電極延出部における枝部と前記検出電極延出部における枝部とを互いに交差させたもので、この構成によれば、クロストークノイズが駆動電極延出部における枝部から検出電極延出部における枝部に到達するため、固着部の長さを長くすることなく、検出電極延出部に発生する電圧を大きくすることができ、その結果、一方の検出電極と端子とを結ぶワイヤー線の断線を、さらに、確実に検知することができるという作用効果を有するものである。
【００１５】
本発明の請求項４に記載の発明は、特に、上面および下面に一方の駆動電極を設けるとともに両側面に一対の検出電極を設けた第１の振動体と、この第１の振動体と平行に設けられるとともに上面にモニター電極を設け、かつ下面に駆動電極を設け、さらに両側面に検出電極を設けた第２の振動体と、前記第１の振動体の一端部と第２の振動体の一端部とを接続するとともに、上面に第１の振動体における駆動電極、検出電極、第２の振動体におけるモニター電極、駆動電極および検出電極をそれぞれ延出させて駆動電極延出部、検出電極延出部およびモニター電極延出部を形成した固着部とからなる音叉と、この音叉における固着部を上面に固着するとともに少なくとも５つの端子挿入孔を設け、この端子挿入孔に少なくとも５つの端子を挿通させた基台と、この基台における端子と前記音叉の固着部における駆動電極延出部、検出電極延出部およびモニター電極延出部とを電気的に接続するワイヤー線とを備え、前記第１の振動体および第２の振動体における駆動電極と検出電極との間隙を略同一にすることにより、第１の振動体および第２の振動体における駆動電極と両隣の検出電極との間に生じる静電容量を略同一にするとともに、音叉における固着部に駆動電極を延出させて形成した第１の振動体あるいは第２の振動体における駆動電極延出部の両隣に、この駆動電極延出部との間隙が略同一になるように第１の振動体あるいは第２の振動体における検出電極延出部を延出形成することにより、駆動電極延出部と両隣の検出電極延出部との間に生じる静電容量を略同一にしたもので、この構成によれば、角速度センサに角速度を付与しない状態において、音叉における一方の検出電極と端子とを結ぶワイヤー線が外れてしまうと、駆動電極から発生する高周波成分によるクロストークノイズが他方の検出電極のみに誘電体よりなる振動体を伝わって到達することになり、その結果、クロストークノイズにより一対の検出電極に発生する電荷が互いに打ち消しあうことはなくなるため、常時、他方の検出電極に電圧が発生することになり、これにより、一方の検出電極と端子とを結ぶワイヤー線の断線を検知することができるとともに、クロストークノイズにより発生する電荷が駆動電極延出部から誘電体よりなる固着部を伝わって検出電極延出部に到達することになるため、音叉における一方の検出電極延出部と電気的に接続された検出電極と端子とを結ぶワイヤー線が外れてしまうと、駆動電極延出部から発生する高周波成分によるクロストークノイズが他方の検出電極延出部のみに誘電体よりなる固着部を伝わって到達することになり、その結果、クロストークノイズにより一対の検出電極延出部に発生する電荷が互いに打ち消しあうことはなくなるため、常時、他方の検出電極延出部に発生する電圧は大となり、これにより、一方の検出電極と端子とを結ぶワイヤー線の断線を確実に検知することができるという作用効果を有するものである。
【００１６】
本発明の請求項５に記載の発明は、特に、固着部に駆動電極を延出させて形成した第１の振動体における駆動電極延出部に第１の振動体における検出電極延出部を沿わせるとともに、前記固着部に駆動電極を延出させて形成した第２の振動体における駆動電極延出部に第２の振動体における検出電極延出部を沿わせ、かつ前記第１の振動体における駆動電極延出部に検出電極延出部を沿わせる距離およびそれらの間隙と、第２の振動体における駆動電極延出部に検出電極延出部を沿わせる距離およびそれらの間隙とを略同一にすることにより、駆動電極延出部と検出電極延出部との間に生じる静電容量を互いに略同一にしたもので、この構成によれば、駆動電極延出部に検出電極延出部が沿う距離がさらに長くなるため、クロストークノイズが検出電極延出部に到達することにより発生する電荷が大となり、その結果、一方の検出電極と端子とを結ぶワイヤー線の断線を、さらに確実に検知することができるという作用効果を有するものである。
【００１７】
本発明の請求項６に記載の発明は、特に、駆動電極延出部を枝部を有する櫛形状に形成するとともに、検出電極延出部を枝部を有する櫛形状に形成し、さらに前記駆動電極延出部における枝部と前記検出電極延出部における枝部とを互いに交差させたもので、この構成によれば、クロストークノイズが駆動電極延出部における枝部から検出電極延出部における枝部に到達するため、固着部の長さを長くすることなく、検出電極延出部に発生する電圧を大きくすることができ、その結果、一方の検出電極延出部とワイヤー線との断線を、さらに確実に検知することができるという作用効果を有するものである。
【００１８】
【発明の実施の形態】
（実施の形態１）
以下、実施の形態１を用いて、本発明の特に請求項１，２および請求項４，５に記載の発明について説明する。
【００１９】
図１は本発明の実施の形態１における角速度センサの斜視図、図２は同角速度センサにおける音叉を基台から取り外した状態を示す音叉の下面図である。
【００２０】
図１、図２において、２１は互いに結晶軸の異なる単結晶の水晶製の薄板を貼り合わせた誘電体よりなる第１の振動体で、この第１の振動体２１は、表面に第１の駆動電極２２を設けるとともに、裏面に図２に示すように、第２の駆動電極２３を設け、かつ外側面に例えば金、アルミ、ニッケル等からなる第１の検出電極２４を設け、さらに内側面に例えば金、アルミ、ニッケル等からなる第２の検出電極２５を設けている。２６は互いに結晶軸の異なる単結晶の水晶製の薄板を貼り合わせた誘電体よりなる第２の振動体で、この第２の振動体２６は、表面に、例えば金、アルミ、ニッケル等からなるモニター電極２７を設けるとともに、裏面に第１の振動体２１における第１の駆動電極２２と電気的に接続された第３の駆動電極２８を設け、かつ外側面に第３の検出電極２９を設け、さらに内側面に第４の検出電極３０を設けている。そして、第１の駆動電極２２と第１の検出電極２４との間隙を第１の駆動電極２２と第２の検出電極２５との間隙と略同一にするとともに、第２の駆動電極２３と第１の検出電極２４との間隙を第２の駆動電極２３と第２の検出電極２５との間隙と略同一にし、かつモニター電極２７と第３の検出電極２９との間隙をモニター電極２７と第４の検出電極３０との間隙と略同一にし、さらに第３の駆動電極２８と第３の検出電極２９との間隙を第３の駆動電極２８と第４の検出電極３０との間隙と略同一になるように構成している。３１は水晶製の誘電体よりなる固着部で、第１の振動体２１の一端と第２の振動体２６の一端を接続するとともに、振動しないように構成されている。そして、第１の振動体２１、第２の振動体２６および固着部３１により音叉３２を構成している。
【００２１】
また、音叉３２における固着部３１の上面には、第１の振動体２１における第１の駆動電極２２を延出させて形成した第１の駆動電極延出部３３を設けており、かつこの第１の駆動電極延出部３３の一方の側には、第１の検出電極２４を延出させて形成した第１の検出電極延出部３４を設けるとともに、他方の側には、第２の検出電極２５を延出させて形成した第２の検出電極延出部３５を設けている。そしてまた、第１の振動体２１における第１の駆動電極２２および第１の駆動電極延出部３３をさらに固着部３１において延出させて形成した第２の駆動電極延出部３６に第２の振動体における第３の検出電極２９を延出させて形成した第３の検出電極延出部３７を沿わせるとともに、第１の振動体２１における第２の駆動電極２３および下面の第３の駆動電極延出部３８をさらに固着部３１において延出させて形成した第４の駆動電極延出部３９に前記第１の振動体２１における第１の検出電極延出部３４を沿わせ、かつ前記第１の振動体２１における第２の駆動電極延出部３６に第２の振動体２６における第３の検出電極延出部３７を沿わせる距離およびそれらの間隙と、第１の振動体２１における第４の駆動電極延出部３９に第１の振動体２１における第１の検出電極延出部３４を沿わせる距離およびそれらの間隙とを略同一にしている。さらに、前記固着部３１の下面に位置するように第１の振動体２１における第１の検出電極２４を延出させて形成した第４の検出電極延出部４０を第１の振動体２１における第２の駆動電極２３を延出させて形成した第３の駆動電極延出部３８に沿わせるとともに、前記固着部３１の下面に位置するように第２の振動体２６における第３の駆動電極２８を延出させて形成した第５の駆動電極延出部４１に第２の振動体２６における第３の検出電極２９を延出させて形成した第５の検出電極延出部４２を沿わせ、かつ前記第１の振動体２１における第３の駆動電極延出部３８に第４の検出電極延出部４０を沿わせる距離およびそれらの間隙と、第２の振動体２６における第５の駆動電極延出部４１に第５の検出電極延出部４２を沿わせる距離およびそれらの間隙とを略同一にしている。さらにまた、前記音叉３２における固着部３１の上面には、モニター電極２７を延出させて形成したモニター電極延出部２７ａを設けている。
【００２２】
４３は金属製の基台で、この基台４３は上面に支持部４４を設けており、この支持部４４の上面に前記音叉３２における固着部３１の一部を固着している。また、前記基台４３には５つの端子挿入孔４５を設けており、そしてこの端子挿入孔４５には、第１の駆動電極２２、第１の駆動電極延出部３３および第２の駆動電極延出部３６とワイヤー線４６により電気的に接続された第１の駆動用端子４７と、第２の駆動電極２３、図２に示す第３の駆動電極延出部３８および第４の駆動電極延出部３９とワイヤー線４６により電気的に接続された第２の駆動用端子４８と、第１の検出電極２４および第１の検出電極延出部３４とワイヤー線４６により電気的に接続された第１の検出用端子４９と、第２の検出電極２５、第４の検出電極３０と第２の検出電極延出部３５とワイヤー線４６により電気的に接続された第２の検出用端子５０と、モニター電極２７およびモニター電極延出部２７ａとワイヤー線４６により電気的に接続されたモニター用端子５１とを、それぞれガラスからなる絶縁物５２を介して設けている。また、前記第１の振動体２１における第１の検出電極２４と、第２の振動体２６における第３の検出電極２９とは第１の検出電極延出部３４、ジャンパー用ワイヤー線５３および第３の検出電極延出部３７を介して電気的に接続されている。
【００２３】
以上のように構成された本発明の一実施の形態における角速度センサについて、次に、その組立方法を説明する。
【００２４】
まず、互いに結晶層の異なる単結晶からなる水晶製の薄板を貼り合わせることにより第１の振動体２１、第２の振動体２６および固着部３１からなる音叉３２を形成する。
【００２５】
次に、第１の振動体２１の正面に第１の駆動電極２２、裏面に第２の駆動電極２３、外側面に第１の検出電極２４、内側面に第２の検出電極２５を、第２の振動体２６の正面にモニター電極２７、裏面に第３の駆動電極２８、内側面に第４の検出電極３０、外側面に第３の検出電極２９を、さらに固着部３１の上面に第１の駆動電極延出部３３、第１の検出電極延出部３４、第２の検出電極延出部３５、第２の駆動電極延出部３６、第３の検出電極延出部３７および第４の駆動電極延出部３９を、固着部３１の下面に第４の検出電極延出部４０、第３の駆動電極延出部３８、第５の駆動電極延出部４１および第５の検出電極延出部４２を金を蒸着することによりそれぞれ形成する。
【００２６】
次に、基台４３における端子挿入孔４５に第１の駆動用端子４７、第２の駆動用端子４８、第１の検出用端子４９、第２の検出用端子５０およびモニター用端子５１をそれぞれ挿通させた後、それぞれの端子挿入孔４５にガラスからなる絶縁物５２を充填する。
【００２７】
次に、音叉３２における固着部３１を基台４３における支持部４４の上面に固着した後、基台４３における第１の駆動用端子４７に音叉３２における第２の駆動電極延出部３６を、第２の駆動用端子４８に第４の駆動電極延出部３９を、第１の検出用端子４９に第１の検出電極延出部３４を、第２の検出用端子５０に第２の検出電極延出部３５を、モニター用端子５１にモニター電極延出部２７ａを、それぞれ金からなるワイヤー線４６を介してワイヤーボンディングにより電気的に接続する。
【００２８】
次に、音叉３２における固着部３１の上面で、第１の検出電極延出部３４を第３の検出電極延出部３７にジャンパー用ワイヤー線５３を介してワイヤーボンディングにより電気的に接続する。
【００２９】
以上のようにして組み立てられた本発明の実施の形態１における角速度センサについて、次に、その動作を説明する。
【００３０】
基台４３における第１の駆動用端子４７および第２の駆動用端子４８に実効値約３００ｍｖの交流電圧を印加する。このとき、まず、第２の駆動用端子４８および第４の駆動電極延出部３９を介して、図３に示すように、第１の振動体２１における第２の駆動電極２３に正電圧を印加するとともに、第１の駆動用端子４７、第２の駆動電極延出部３６および第１の駆動電極延出部３３を介して第１の駆動電極２２に負電圧を印加すると、第１の検出電極２４側では、水晶製の薄板における結晶軸の方向と電荷の方向が一致するため、伸びることになり、一方、第２の検出電極２５側では、結晶軸の方向と電荷の方向が反対になるため、縮むことになり、その結果、第１の振動体２１が第２の振動体２６側に傾く。次に、第２の駆動用端子４８、第４の駆動電極延出部３９および第３の駆動電極延出部３８を介して、図４に示すように、第１の振動体２１における第２の駆動電極２３に負電圧を印加するとともに、第１の駆動用端子４７、第２の駆動電極延出部３６および第１の駆動電極延出部３３を介して第１の駆動電極２２に正電圧を印加すると、第１の検出電極２４側では、水晶製の薄板における結晶軸の方向と電荷の方向が反対になるため、縮むことになり、一方、第２の検出電極２５側では、結晶軸の方向と電荷の方向が一致するため、延びることになり、その結果、第１の振動体２１が外側、すなわち、第２の振動体２６とは反対側の方向に傾く。
【００３１】
そして、第２の振動体２６における第３の駆動電極２８およびモニター電極２７にも同様に交流電圧を印加すると、第１の振動体２１と第２の振動体２６は固着部３１により機械的に接続されているため、第１の振動体２１および第２の振動体２６は固着部３１の長手方向に駆動方向の固有振動数において速度Ｖで屈曲振動する。そしてまた、この第１の振動体２１および第２の振動体２６が屈曲振動している状態において、音叉３２が音叉３２の長手方向の中心軸周りに角速度ωで回転すると、第１の振動体２１および第２の振動体２６にＦ＝２ｍｖωのコリオリ力が発生する。このコリオリ力により、第１の検出電極２４に発生する電荷を第１の検出電極延出部３４を介して第１の検出用端子４９に、第２の検出電極２５および第４の検出電極３０に発生する電荷を第２の検出電極延出部３５を介して第２の検出用端子５０に、第３の検出電極２９に発生する電荷を第３の検出電極延出部３７、ジャンパー用ワイヤー線５３および第１の検出電極延出部３４を介して第１の検出用端子４９に入力し、さらに、第１の検出用端子４９および第２の検出用端子５０の出力電圧を差動増幅器（図示せず）を介して相手側のコンピューター（図示せず）に差動の出力電圧を入力することにより、角速度を検出するものである。
【００３２】
ここで、角速度が角速度センサに負荷されない状態において、強い振動が角速度センサに加わり、第２の検出電極延出部３５からワイヤー線４６が外れた場合を考えて見ると、本発明の実施の形態１における角速度センサにおいては、第１の駆動電極２２から発生する高周波成分によるクロストークノイズは誘電体よりなる第１の振動体２１の容量結合を介して第１の検出電極２４および第２の検出電極２５に伝わるが、第２の検出電極延出部３５からワイヤー線４６が外れているため、第１の検出電極２４に発生した電圧約３Ｖのみが第１の検出電極延出部３４および第１の検出用端子４９を介して差動増幅器（図示せず）に入力されることになる。この場合、本発明の実施の形態１においては、第１の振動体２１における第１の駆動電極２２と、第１の検出電極２４および第２の検出電極２５との間隙を略同一にすることにより、第１の振動体２１における第１の駆動電極２２と両隣に位置する第１の検出電極２４および第２の検出電極２５との間に生じる静電容量を略同一にしているため、角速度センサに角速度を付与しない状態において、音叉３２における第２の検出電極２５と第２の検出用端子５０とを第２の検出電極延出部３５を介して結ぶワイヤー線４６が外れてしまうと、第１の駆動電極２２から発生する高周波成分によるクロストークノイズは第１の検出電極２４のみに誘電体よりなる第１の振動体２１を伝わって到達することになり、その結果、クロストークノイズにより第１の検出電極２４および第２の検出電極２５に発生する電荷が互いに打ち消しあうことはなくなるため、常時、第２の検出電極２５に電圧が発生することになり、これにより、第２の検出電極延出部３５と第２の検出用端子５０とを結ぶワイヤー線４６の断線を検知することができるという作用効果を有するものである。
【００３３】
また、第１の駆動電極延出部３３から発生する高周波成分によるクロストークノイズは誘電体よりなる固着部３１の容量結合を介して第１の検出電極延出部３４および第２の検出電極延出部３５に伝わるが、第２の検出電極延出部３５からワイヤー線４６が外れているため、第１の検出電極延出部３４に発生した電圧約１．５Ｖのみが第１の検出電極延出部３４および第１の検出用端子４９を介して差動増幅器（図示せず）に入力されることになる。そして、前述した第１の駆動電極２２から第１の検出電極２４に入力される約３Ｖに加算した合計約４．５Ｖが第１の検出用端子４９を介して差動増幅器（図示せず）に入力されることになる。この場合、本発明の実施の形態１においては、固着部３１に第１の振動体２１における第１の駆動電極２２を延出させて形成した第１の駆動電極延出部３３の両隣に、この第１の駆動電極延出部３３との間隙が略同一になるように第１の振動体２１における第１の検出電極延出部３４および第２の検出電極延出部３５を延出形成することにより、第１の駆動電極延出部３３と両隣の第１の検出電極延出部３４および第２の検出電極延出部３５との間に生じる静電容量を略同一にしているため、第１の駆動電極延出部３３からクロストークノイズにより発生する電荷は誘電体よりなる固着部３１を伝わって第１の検出電極延出部３４および第２の検出電極延出部３５に到達することになり、その結果、音叉３２における第２の検出電極２５と電気的に接続された第２の検出電極延出部３５と第２の検出用端子５０とを結ぶワイヤー線４６が外れてしまうと、第１の駆動電極延出部３３から発生する高周波成分によるクロストークノイズは第１の検出電極延出部３４のみに誘電体よりなる固着部３１を伝わって到達することになり、これにより、クロストークノイズにより第１の検出電極延出部３４および第２の検出電極延出部３５に発生する電荷が互いに差動増幅器（図示せず）において打ち消しあうことはなくなるため、常時、第１の検出電極延出部３４に発生する電圧は大となり、その結果、第２の検出電極２５と電気的に接続された第２の検出電極延出部３５と第２の検出用端子５０とを結ぶワイヤー線４６の断線を確実に検知することができるという作用効果を有するものである。
【００３４】
次に、例えば１００ｄｅｇ／ｓｅｃの角速度が角速度センサに負荷されている場合を考えて見ると、本発明の実施の形態１における角速度センサにおいては、負荷されている角速度の方向により、出力電圧が０．５Ｖあるいは４．５Ｖとなる。差動増幅器（図示せず）の出力信号はクランプ回路（図示せず）に入力されている。そして、クランプ回路（図示せず）により、差動増幅器（図示せず）の出力信号が０Ｖ以下あるいは５Ｖ以上となったときに、ワイヤー線４６の断線を検知するように構成されている。前述したように、第２の検出電極延出部３５からワイヤー線４６が外れると、第１の検出電極２４に約３Ｖの電圧が生じるとともに、第１の検出電極延出部３４に約１．５Ｖの電圧が発生するため、これらを合わせた４．５Ｖが第１の検出用端子４９を介して、差動増幅器（図示せず）に入力されることになる。したがって、角速度の負荷により、出力電圧が約０．５Ｖになっている状態においても、差動増幅器（図示せず）に入力された４．５Ｖとの合計が５Ｖを超えるため、クランプ回路（図示せず）によってクランプされることになり、これにより、第２の検出電極延出部３５と第２の検出用端子５０とを結ぶワイヤー線４６の断線を検知することができるものである。
【００３５】
同様に、角速度が角速度センサに負荷されない状態において、強い振動が角速度センサに加わり、第１の検出電極延出部３４からワイヤー線４６が外れた場合を考えて見ると、本発明の実施の形態１における角速度センサにおいては、第１の駆動電極２２から発生する高周波成分によるクロストークノイズは誘電体よりなる第１の振動体２１の容量結合を介して第１の検出電極２４および第２の検出電極２５に伝わるが、第１の検出電極延出部３４からワイヤー線４６が外れているため、第２の検出電極２５に発生した電圧約３Ｖのみが第２の検出電極延出部３５および第２の検出用端子５０を介して差動増幅器（図示せず）に入力されることになる。また、第１の駆動電極延出部３３から発生する高周波成分によるクロストークノイズは誘電体よりなる固着部３１の容量結合を介して第１の検出電極延出部３４および第２の検出電極延出部３５に伝わるが、第１の検出電極延出部３４からワイヤー線４６が外れているため、第２の検出電極延出部３５に発生した電圧約１．５Ｖのみがワイヤー線４６および第２の検出用端子５０を介して差動増幅器（図示せず）に入力されることになる。そして、前述した第１の駆動電極２２から第２の検出電極２５に入力される電圧約３Ｖに、第２の検出電極延出部３５に発生した電圧約１．５Ｖを加算した合計約４．５Ｖの電圧は第２の検出用端子５０を介して差動増幅器（図示せず）に入力されることになる。
【００３６】
さらに、角速度が角速度センサに負荷されない状態において、強い振動が角速度センサに加わり、ジャンパー用ワイヤー線５３が第１の検出電極延出部３４から外れた場合を考えて見ると、本発明の実施の形態１における角速度センサにおいては、図２に示すように、第３の駆動電極２８から発生する高周波成分によるクロストークノイズが誘電体よりなる第２の振動体２６の容量結合を介して第３の検出電極２９および第４の検出電極３０に伝わるが、第１の検出電極延出部３４からジャンパー用ワイヤー線５３が外れているため、第４の検出電極３０に発生した電圧約３Ｖのみが第２の検出電極延出部３５、ワイヤー線４６および第２の検出用端子５０を介して差動増幅器（図示せず）に入力されることになる。また、図２に示すように、第３の駆動電極延出部３８から発生する高周波成分によるクロストークノイズは誘電体よりなる固着部３１の容量結合を介して第４の検出電極延出部４０に伝わり、一方、第５の駆動電極延出部４１から発生する高周波成分によるクロストークノイズは誘電体よりなる固着部３１の容量結合を介して第５の検出電極延出部４２に伝わるが、第１の検出電極延出部３４からジャンパー用ワイヤー線５３が外れているため、第１の検出電極延出部３４に発生した電圧約１．７Ｖのみがワイヤー線４６および第１の検出用端子４９を介して差動増幅器（図示せず）に入力されることになる。さらに、第２の駆動電極延出部３６から発生する高周波成分によるクロストークノイズは誘電体よりなる固着部３１の容量結合を介して第３の検出電極延出部３７に伝わるとともに、第４の駆動電極延出部３９から発生する高周波成分によるクロストークノイズは誘電体よりなる固着部３１の容量結合を介して第１の検出電極延出部３４に伝わるが、第１の検出電極延出部３４からジャンパー用ワイヤー線５３が外れているため、第１の検出電極延出部３４に発生した電圧約２．４Ｖのみがワイヤー線４６および第１の検出用端子４９を介して差動増幅器（図示せず）に入力されることになる。そして、前述した第４の検出電極３０に発生した電圧約３Ｖに、第１の検出電極延出部３４に発生した電圧約１．７Ｖを加算した合計約７．１Ｖの電圧はワイヤー線４６および第１の検出用端子４９を介して差動増幅器（図示せず）に入力されることになる。
【００３７】
なお、上記本発明の実施の形態１における角速度センサにおいては、第１の振動体２１および第２の振動体２６のそれぞれの一端を固着部３１で接続することにより音叉３２を構成したが、四角柱状あるいは三角柱状一つの振動体で音叉を構成しても本発明の実施の形態１と同様の作用効果を有するものである。
【００３８】
（実施の形態２）
以下、実施の形態２を用いて、本発明の特に請求項３および請求項６に記載の発明について説明する。
【００３９】
図５は本発明の実施の形態２における角速度センサの音叉の上面図、図６は同角速度センサの音叉の下面図である。
【００４０】
なお、この実施の形態２においては、上記実施の形態１の構成と同様の構成を有するものについては、同一符号を付してその説明を省略し、実施の形態１と異なる点のみを説明する。
【００４１】
図５、図６において、音叉３２における固着部３１の上面には、第１の振動体２１における第１の駆動電極２２を延出させて形成した枝部６１を有する櫛形状の第１の駆動電極延出部３３ａを設けている。そして、第１の駆動電極延出部３３ａの一方の側に第１の検出電極２４を延出させて形成した枝部６２を有する櫛形状の第１の検出電極延出部３４ａを設けるとともに、他方の側に第２の検出電極２５を延出させて形成した枝部６３を有する第２の検出電極延出部３５ａを設けている。そしてまた、これらは第１の駆動電極延出部３３ａにおける枝部６１と第１の検出電極延出部３４ａにおける枝部６２とを互いに交差させるとともに、第１の駆動電極延出部３３ａにおける枝部６１と第２の検出電極延出部３５ａにおける枝部６３とを互いに交差させている。
【００４２】
ここで、角速度が角速度センサに負荷されない状態において、強い振動が角速度センサに加わり、第２の検出電極延出部３５ａからワイヤー線４６が外れた場合を考えて見ると、本発明の実施の形態２における角速度センサにおいては、第１の駆動電極延出部３３ａから発生する高周波成分によるクロストークノイズは誘電体よりなる固着部３１の容量結合を介して第１の検出電極延出部３４ａおよび第２の検出電極延出部３５ａに伝わるが、第２の検出電極延出部３５ａからワイヤー線４６が外れているため、第１の検出電極延出部３４ａに発生した電圧約１．３Ｖのみが第１の検出用端子４９を介して差動増幅器（図示せず）に入力されることになる。この場合、本発明の実施の形態２においては、第１の駆動電極延出部３３ａを枝部６１を有する櫛形状に形成するとともに、第１の検出電極延出部３４ａを枝部６２を有する櫛形状に形成し、さらに前記第１の駆動電極延出部３３ａにおける枝部６１と第１の検出電極延出部３４ａにおける枝部６２とを互いに交差させているため、クロストークノイズは第１の駆動電極延出部３３ａにおける枝部６１から第１の検出電極延出部３４ａにおける枝部６２に到達することになり、その結果、固着部３１の長さを長くすることなく、第１の検出電極延出部３４ａに発生する電圧を大きくすることができるため、第２の検出電極延出部３５ａと第２の検出用端子５０とを結ぶワイヤー線４６の断線を、さらに確実に検知することができるという作用効果を有するものである。
【００４３】
また、本発明の実施の形態２においては、上記本発明の実施の形態１と同様、第１の振動体２１における第１の駆動電極２２および第１の駆動電極延出部３３ａをさらに固着部３１において延出させて形成した第２の駆動電極延出部３６ａに第２の振動体２６における第３の検出電極２９を延出させて形成した第３の検出電極延出部３７ａを沿わせるとともに、第１の振動体２１における第２の駆動電極２３および下面の第３の駆動電極延出部３８ａをさらに固着部３１において延出させて形成した第４の駆動電極延出部３９ａに前記第１の振動体２１における第１の検出電極延出部３４ａを沿わせ、かつ前記第１の振動体２１における第２の駆動電極延出部３６ａに第２の振動体２６における第３の検出電極延出部３７ａを沿わせる距離およびそれらの間隙と、第１の振動体２１における第４の駆動電極延出部３９ａに第１の振動体２１における第１の検出電極延出部３４ａを沿わせる距離およびそれらの間隙とを略同一にし、そして前記第２の駆動電極延出部３６ａにおける枝部６４と、第３の検出電極延出部３７ａにおける枝部６５とを互いに交差させるとともに、第４の駆動電極延出部３９ａにおける枝部６６と、第１の検出電極延出部３４ａにおける枝部６７とを互いに交差させているものである。
【００４４】
そしてまた、本発明の実施の形態２においては、図６に示すように、固着部３１の下面に位置するように第１の振動体２１における第１の検出電極２４を延出させて形成した枝部６８を有する櫛形状の第４の検出電極延出部４０ａを第１の振動体２１における第２の駆動電極２３を延出させて形成した枝部６９を有する櫛形状の第３の駆動電極延出部３８ａに沿わせるとともに、前記固着部３１の下面に位置するように第２の振動体２６における第３の駆動電極２８を延出させて形成した枝部７０を有する櫛形状の第５の駆動電極延出部４１ａに第２の振動体２６における第３の検出電極２９を延出させて形成した枝部７１を有する櫛形状の第５の検出電極延出部４２ａを沿わせ、かつ前記第１の振動体２１における第３の駆動電極延出部３８ａに第４の検出電極延出部４０ａを沿わせる距離およびそれらの間隙と、第２の振動体２６における第５の駆動電極延出部４１ａに第５の検出電極延出部４２ａを沿わせる距離およびそれらの間隙とを略同一にし、そして前記第３の駆動電極延出部３８ａにおける枝部６９と、第４の検出電極延出部４０ａにおける枝部６８とを互いに交差させるとともに、第５の駆動電極延出部４１ａにおける枝部７０と、第５の検出電極延出部４２ａにおける枝部７１とを互いに交差させているものである。
【００４５】
【発明の効果】
以上のように本発明の角速度センサによれば、音叉の振動体における駆動電極と検出電極との間隙を略同一にすることにより、駆動電極と両隣に位置する検出電極との間に生じる静電容量を略同一にするとともに、音叉における固着部に一方の駆動電極を延出させて形成した一方の駆動電極延出部に一方の検出電極延出部を沿わせるとともに、前記固着部に他方の駆動電極を延出させて形成した他方の駆動電極延出部に他方の検出電極延出部を沿わせ、かつ前記一方の駆動電極延出部に一方の検出電極延出部を沿わせる距離およびそれらの間隙と、他方の駆動電極延出部に他方の検出電極延出部を沿わせる距離およびそれらの間隙とを略同一にすることにより、一方の駆動電極延出部と一方の検出電極延出部との間に生じる静電容量および他方の駆動電極延出部と他方の検出電極延出部との間に生じる静電容量を互いに略同一にしているため、角速度センサに角速度を付与しない状態において、音叉における一方の検出電極と端子とを結ぶワイヤー線が外れてしまうと、駆動電極から発生する高周波成分によるクロストークノイズは他方の検出電極のみに誘電体よりなる振動体を伝わって到達することになり、その結果、クロストークノイズにより一対の検出電極に発生する電荷が互いに打ち消しあうことはなくなるため、常時、他方の検出電極に電圧が発生することになり、これにより、一方の検出電極と端子とを結ぶワイヤー線の断線を検知することができるという効果を奏するとともに、クロストークノイズにより発生する電荷が駆動電極延出部から誘電体よりなる固着部を伝わって検出電極延出部に到達することになるため、音叉における一方の検出電極延出部と電気的に接続された検出電極と端子とを結ぶワイヤー線が外れてしまうと、駆動電極延出部から発生する高周波成分によるクロストークノイズが他方の検出電極延出部のみに誘電体よりなる固着部を伝わって到達することになり、その結果、クロストークノイズにより一対の検出電極延出部に発生する電荷が互いに打ち消しあうことはなくなるため、常時、他方の検出電極延出部に発生する電圧は大となり、これにより、一方の検出電極と端子とを結ぶワイヤー線の断線を確実に検知することができるという効果を奏するものである。
【図面の簡単な説明】
【図１】本発明の実施の形態１における角速度センサの斜視図
【図２】同要部である音叉を基台から取り外した状態を示す下面図
【図３】同動作を示す断面図
【図４】同動作を示す断面図
【図５】本発明の実施の形態２の角速度センサにおける音叉の上面図
【図６】同要部である音叉の下面図
【図７】従来の角速度センサの斜視図
【符号の説明】
２１第１の振動体
２２第１の駆動電極
２３第２の駆動電極
２４第１の検出電極
２５第２の検出電極
２６第２の振動体
２７モニター電極
２７ａモニター電極延出部
２８第３の駆動電極
２９第３の検出電極
３０第４の検出電極
３１固着部
３２音叉
３３第１の駆動電極延出部
３３ａ櫛形状の第１の駆動電極延出部
３４第１の検出電極延出部
３４ａ櫛形状の第１の検出電極延出部
３５第２の検出電極延出部
３５ａ櫛形状の第２の検出電極延出部
３６第２の駆動電極延出部
３６ａ櫛形状の第２の駆動電極延出部
３７第３の検出電極延出部
３７ａ櫛形状の第３の検出電極延出部
３８第３の駆動電極延出部
３８ａ櫛形状の第３の駆動電極延出部
３９第４の駆動電極延出部
３９ａ櫛形状の第４の駆動電極延出部
４０第４の検出電極延出部
４０ａ櫛形状の第４の検出電極延出部
４１第５の駆動電極延出部
４１ａ櫛形状の第５の駆動電極延出部
４２第５の検出電極延出部
４２ａ櫛形状の第５の検出電極延出部
４３基台
４６ワイヤー線
４７第１の駆動用端子
４８第２の駆動用端子
４９第１の検出用端子
５０第２の検出用端子
５１モニター用端子
５３ジャンパー用ワイヤー線
６１，６２，６３，６４，６５，６６，６７枝部
６８，６９，７０，７１枝部[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an angular velocity sensor used for attitude control of a moving body such as an aircraft or a vehicle, a navigation system, or the like.
[0002]
[Prior art]
  As a conventional angular velocity sensor of this kind, one disclosed in Japanese Patent Laid-Open No. 11-51658 is known.
[0003]
  Hereinafter, a conventional angular velocity sensor will be described with reference to the drawings.
[0004]
  FIG. 7 is a perspective view of a conventional angular velocity sensor.
[0005]
  In FIG. 7, reference numeral 1 denotes a tuning fork, which includes a pair of pillar portions 2 and a fixing portion 3 that connects the end portions of the pillar portions 2. A first drive electrode 4 is provided on the upper surface of each of the pair of column portions 2 in the tuning fork 1, and a second drive electrode 5 is provided on the same plane as the first drive electrode 4. . The tuning fork 1 includes a monitor electrode 6 and a polarization detection electrode 7 on the same surface as the surface on which the first drive electrode 4 and the second drive electrode 5 are provided in the pair of column portions 2, and a pair of A detection electrode 8 is provided on each outer surface of the column part 2. Reference numeral 9 denotes a support portion that supports the fixing portion 3 of the tuning fork 1. Reference numeral 10 denotes a base, and a convex portion 11 is provided on the upper surface, and the lower surface of the support portion 9 is fixed to the upper surface of the convex portion 11. In addition, the base 10 is provided with a terminal 13 inserted through an insulator 12 from the upper surface to the lower surface, and the terminal 13 includes the first drive electrode 4, the second drive electrode 5, and the like in the tuning fork 1. The monitor electrode 6 and the detection electrode 8 are electrically connected by a wire 14.
[0006]
  Next, the operation of the conventional angular velocity sensor configured as described above will be described.
[0007]
  By applying an alternating voltage to the first drive electrode 4 and the second drive electrode 5 in the tuning fork 1, the tuning fork 1 is flexibly vibrated at a natural frequency in the driving direction and at a speed V in the driving direction. In this state, when the tuning fork 1 rotates around the central axis of the tuning fork 1 at an angular velocity ω, a Coriolis force of F = 2 mV · ω is generated in the pair of column portions 2 of the tuning fork 1. The electric charge generated in the detection electrode 8 is amplified by this Coriolis force, and the angular velocity is detected by measuring the output voltage with an external computer or the like (not shown).
[0008]
  Here, when strong vibration is applied to the tuning fork 1 over a long period of time, when the wire wire 14 connecting the first drive electrode 4 and the second drive electrode 5 and the terminal 13 of the base 10 is disconnected, the conventional angular velocity is obtained. In the sensor, since the tuning fork 1 does not vibrate, the disconnection of the wire 14 can be detected.
[0009]
[Problems to be solved by the invention]
  However, in the above-described conventional configuration, if the wire wire 14 connecting one detection electrode 8 and the terminal 13 in the tuning fork 1 is disconnected due to strong vibration applied to the angular velocity sensor, the output voltage is reduced by half. As a result, the sensor is misunderstood as if half the angular velocity is applied. As a result, since the disconnection of the wire 14 cannot be detected, there is a problem that the erroneous angular velocity is detected. .
[0010]
  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object of the present invention is to provide an angular velocity sensor that can reliably detect a disconnection without detecting an erroneous angular velocity.
[0011]
[Means for Solving the Problems]
  In order to achieve the above object, the present invention has the following configuration.
[0012]
  The invention described in claim 1 of the present invention is particularly formed by extending a vibration body provided with a pair of drive electrodes and a pair of detection electrodes, and a pair of drive electrodes and a pair of detection electrodes in the vibration body. A tuning fork comprising a fixed portion having a pair of drive electrode extending portions and a pair of detection electrode extending portions, a base for fixing the fixed portion of the tuning fork and inserting at least four terminals, A wire wire for electrically connecting the terminal and the drive electrode extension or detection electrode extension in the fixing portion of the tuning fork, and the gap between the drive electrode and the detection electrode in the tuning fork vibrator is substantially the same. By doing so, the capacitance generated between the drive electrode and the adjacent detection electrodes is made substantially the same.In addition, the detection electrode extension is extended on both sides of the drive electrode extension formed by extending the drive electrode to the fixed part of the tuning fork so that the gap with the drive electrode extension is substantially the same. By forming the capacitance, the capacitance generated between the drive electrode extension and the adjacent detection electrode extension is made substantially the same.Thus, according to this configuration, if the wire connecting the one detection electrode and the terminal of the tuning fork is disconnected in a state where no angular velocity is applied to the angular velocity sensor, crosstalk noise due to high frequency components generated from the drive electrode is reduced. Only the other detection electrode reaches the vibration body made of a dielectric material, and as a result, the charges generated in the pair of detection electrodes do not cancel each other due to crosstalk noise. A voltage is generated in the electrode, and this has the effect of detecting the disconnection of the wire connecting the one detection electrode and the terminal.At the same time, the electric charge generated by the crosstalk noise travels from the drive electrode extension portion to the detection electrode extension portion through the fixed portion made of a dielectric, so that it is electrically connected to one detection electrode extension portion of the tuning fork. If the wire connecting the detection electrode connected to the terminal and the terminal is disconnected, the crosstalk noise due to the high-frequency component generated from the drive electrode extension portion causes the fixed detection portion made of a dielectric material only to the other detection electrode extension portion. As a result, the electric charges generated in the pair of detection electrode extensions due to crosstalk noise do not cancel each other, so that the voltage generated in the other detection electrode extension is always large. Thus, the disconnection of the wire connecting the one detection electrode and the terminal can be reliably detected.
[0013]
  Claims of the invention2In particular, the invention described in (1) has one detection electrode extension portion along one drive electrode extension portion formed by extending one drive electrode to a fixation portion in a tuning fork, and the other fixation portion to the other fixation electrode portion. A distance for extending the other detection electrode extension part along the other drive electrode extension part formed by extending the drive electrode, and extending one detection electrode extension part along the one drive electrode extension part; and By making the gap, the distance along which the other detection electrode extension part extends along the other drive electrode extension part, and the gap between them substantially equal, one drive electrode extension part and one detection electrode extension The capacitance generated between the extended portion and the other drive electrode extended portion and the other detected electrode extended portion are substantially the same, and according to this configuration, the drive Since the distance along which the detection electrode extension extends along the electrode extension is further increased, The electric charge generated by the loss talk noise reaching the detection electrode extension increases, and as a result, the disconnection of the wire connecting the one detection electrode and the terminal can be detected more reliably. It is what has.
[0014]
  Claims of the invention3In particular, the drive electrode extension portion is formed in a comb shape having a branch portion, the detection electrode extension portion is formed in a comb shape having a branch portion, and the branch in the drive electrode extension portion is further formed. And the branch part of the detection electrode extension part cross each other. According to this configuration, crosstalk noise reaches the branch part of the detection electrode extension part from the branch part of the drive electrode extension part. Therefore, it is possible to increase the voltage generated at the detection electrode extension without increasing the length of the fixing portion, and as a result, it is possible to further reliably disconnect the wire connecting the one detection electrode and the terminal. It has the effect that it can be detected.
[0015]
  Claims of the invention4In particular, the invention described in 1 is provided with a first vibrating body provided with one drive electrode on the upper surface and the lower surface and a pair of detection electrodes on both side surfaces, and provided in parallel with the first vibrating body and on the upper surface. Connecting a second vibrator having a monitor electrode, a drive electrode on the lower surface, and a detection electrode on both sides, and one end of the first vibrator and one end of the second vibrator In addition, the drive electrode, the detection electrode, the monitor electrode, the drive electrode, and the detection electrode in the second vibrating body are extended on the upper surface to extend the drive electrode, the detection electrode extension, and the monitor, respectively. A tuning fork composed of a fixing portion having an electrode extension portion, a fixing base in which the fixing portion of the tuning fork is fixed to the upper surface, at least five terminal insertion holes are provided, and at least five terminals are inserted into the terminal insertion holes. When A wire wire for electrically connecting a terminal of the base and a drive electrode extension portion, a detection electrode extension portion, and a monitor electrode extension portion in the fixing portion of the tuning fork, the first vibrator and the first By making the gap between the drive electrode and the detection electrode in the two vibration bodies substantially the same, the capacitance generated between the drive electrode and the adjacent detection electrodes in the first vibration body and the second vibration body is substantially reduced. SameIn addition, the gap with the drive electrode extension is substantially the same on both sides of the drive electrode extension in the first vibrator or the second vibrator formed by extending the drive electrode to the fixing part in the tuning fork. The capacitance generated between the drive electrode extension part and the adjacent detection electrode extension part by extending the detection electrode extension part in the first vibrator or the second vibrator so as to become Are almost identicalThus, according to this configuration, if the wire wire connecting one detection electrode and the terminal in the tuning fork is disconnected in a state where the angular velocity is not applied to the angular velocity sensor, crosstalk noise due to high frequency components generated from the drive electrode is generated. Only the other detection electrode reaches the vibration body made of a dielectric material, and as a result, the charges generated in the pair of detection electrodes do not cancel each other due to crosstalk noise. A voltage will be generated in the electrode, which can detect the disconnection of the wire connecting the one detection electrode and the terminal.In both cases, the electric charge generated by the crosstalk noise travels from the drive electrode extension part to the detection electrode extension part through the fixed part made of the dielectric, so that it is electrically connected to one detection electrode extension part of the tuning fork. If the wire connecting the detection electrode connected to the terminal and the terminal is disconnected, the crosstalk noise due to the high-frequency component generated from the drive electrode extension portion causes the fixed detection portion made of a dielectric material only to the other detection electrode extension portion. As a result, the electric charges generated in the pair of detection electrode extensions due to crosstalk noise do not cancel each other, so that the voltage generated in the other detection electrode extension is always large. Thus, the disconnection of the wire connecting the one detection electrode and the terminal can be reliably detected.
[0016]
  Claims of the invention5In particular, the invention described in (1) has the detection electrode extension portion in the first vibrating body along the driving electrode extension portion in the first vibrating body formed by extending the driving electrode in the fixing portion, and the fixing The drive electrode extending portion of the second vibrating body is formed along the drive electrode extending portion of the second vibrating body, and the driving electrode extending portion of the first vibrating body is extended. By making the distance along which the detection electrode extension part runs along the part and the gap between them, and the distance along which the detection electrode extension part runs along the drive electrode extension part in the second vibrator and the gap between them are substantially the same The capacitance generated between the drive electrode extension and the detection electrode extension is substantially the same. According to this configuration, the distance along which the detection electrode extension extends along the drive electrode extension Since it becomes longer, crosstalk noise is generated at the detection electrode extension. Charge becomes large caused by reaching, with the result that those having effect that breakage of the wire line connecting the one detection electrode and the terminal, it is possible to more reliably detected.
[0017]
  Claims of the invention6In particular, the drive electrode extension portion is formed in a comb shape having a branch portion, the detection electrode extension portion is formed in a comb shape having a branch portion, and the branch in the drive electrode extension portion is further formed. And the branch part of the detection electrode extension part cross each other. According to this configuration, crosstalk noise reaches the branch part of the detection electrode extension part from the branch part of the drive electrode extension part. Therefore, it is possible to increase the voltage generated in the detection electrode extension without increasing the length of the fixing portion, and as a result, the disconnection between one detection electrode extension and the wire wire can be more reliably performed. It has the effect that it can be detected.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
  (Embodiment 1)
  Hereinafter, using the first embodiment, the present invention is particularly claimed.1, 2And claims4,5Will be described.
[0019]
  FIG. 1 is a perspective view of an angular velocity sensor according to Embodiment 1 of the present invention, and FIG. 2 is a bottom view of the tuning fork showing a state in which the tuning fork in the angular velocity sensor is removed from a base.
[0020]
  In FIGS. 1 and 2, reference numeral 21 denotes a first vibrating body made of a dielectric material in which single crystal quartz thin plates having different crystal axes are bonded to each other. As shown in FIG. 2, the drive electrode 22 is provided, the second drive electrode 23 is provided on the back surface, the first detection electrode 24 made of, for example, gold, aluminum, nickel, or the like is provided on the outer surface, and the inner surface is further provided. The second detection electrode 25 made of, for example, gold, aluminum, nickel or the like is provided. Reference numeral 26 denotes a second vibrating body made of a dielectric material formed by bonding single crystal quartz thin plates having different crystal axes. The second vibrating body 26 is made of, for example, gold, aluminum, nickel or the like on the surface. A monitor electrode 27 is provided, a third drive electrode 28 electrically connected to the first drive electrode 22 in the first vibrating body 21 is provided on the back surface, and a third detection electrode 29 is provided on the outer surface. Further, a fourth detection electrode 30 is provided on the inner surface. The gap between the first drive electrode 22 and the first detection electrode 24 is made substantially the same as the gap between the first drive electrode 22 and the second detection electrode 25, and the second drive electrode 23 and the second detection electrode 25 are The gap between the first detection electrode 24 and the second drive electrode 23 and the second detection electrode 25 is substantially the same as the gap between the monitor electrode 27 and the third detection electrode 29. The gap between the third drive electrode 28 and the third detection electrode 29 is substantially the same as the gap between the third drive electrode 28 and the fourth detection electrode 30. It is configured to be. Reference numeral 31 denotes a fixing portion made of a quartz dielectric, which connects one end of the first vibrating body 21 and one end of the second vibrating body 26 and is configured not to vibrate. The first vibrating body 21, the second vibrating body 26 and the fixing portion 31 constitute a tuning fork 32.
[0021]
  A first drive electrode extending portion 33 formed by extending the first drive electrode 22 of the first vibrating body 21 is provided on the upper surface of the fixing portion 31 of the tuning fork 32. A first detection electrode extension 34 formed by extending the first detection electrode 24 is provided on one side of one drive electrode extension 33, and a second is provided on the other side. A second detection electrode extending portion 35 formed by extending the detection electrode 25 is provided. Further, the second drive electrode extension 36 formed by extending the first drive electrode 22 and the first drive electrode extension 33 in the first vibrating body 21 further in the fixing portion 31 is secondly added. The third detection electrode extension portion 37 formed by extending the third detection electrode 29 in the vibration body is provided along the second drive electrode 23 and the third surface of the lower surface of the first vibration body 21. The first detection electrode extension portion 34 of the first vibrating body 21 is aligned with the fourth drive electrode extension portion 39 formed by further extending the drive electrode extension portion 38 at the fixing portion 31, and The distance along which the third drive electrode extension part 37 of the second vibrator 26 extends along the second drive electrode extension part 36 of the first vibrator 21 and the gap between them, and the first vibrator 21 In the fourth drive electrode extension 39 in FIG. A distance and their gap placed along the first detection electrode extending portion 34 in the body 21 are substantially the same. Further, a fourth detection electrode extending portion 40 formed by extending the first detection electrode 24 in the first vibrating body 21 so as to be positioned on the lower surface of the fixing portion 31 is provided in the first vibrating body 21. The third drive electrode in the second vibrating body 26 is positioned along the third drive electrode extension portion 38 formed by extending the second drive electrode 23 and located on the lower surface of the fixing portion 31. The fifth detection electrode extension portion 42 formed by extending the third detection electrode 29 of the second vibrating body 26 is placed along the fifth drive electrode extension portion 41 formed by extending the number 28. And the distance along which the fourth detection electrode extension 40 extends along the third drive electrode extension 38 in the first vibrator 21 and the gap between them, and the fifth drive in the second vibrator 26 The distance for extending the fifth detection electrode extension 42 to the electrode extension 41 is as follows. Beauty and their gap is substantially the same. Furthermore, a monitor electrode extension portion 27 a formed by extending the monitor electrode 27 is provided on the upper surface of the fixing portion 31 in the tuning fork 32.
[0022]
  Reference numeral 43 denotes a metal base. The base 43 has a support portion 44 provided on the upper surface, and a part of the fixing portion 31 of the tuning fork 32 is fixed to the upper surface of the support portion 44. The base 43 is provided with five terminal insertion holes 45. The terminal insertion holes 45 have a first drive electrode 22, a first drive electrode extension 33, and a second drive electrode. The first drive terminal 47, the second drive electrode 23, the third drive electrode extension 38 and the fourth drive electrode shown in FIG. 2 electrically connected to the extension 36 and the wire 46 The second drive terminal 48 electrically connected by the extension part 39 and the wire line 46, and the first detection electrode 24 and the first detection electrode extension part 34 and the wire line 46 are electrically connected. The first detection terminal 49, the second detection electrode 25, the fourth detection electrode 30, the second detection electrode extension 35, and the second detection terminal electrically connected by the wire 46 50, monitor electrode 27, monitor electrode extension 27a, and wire A monitor terminal 51 which is electrically connected by line 46, respectively provided via an insulator 52 made of glass. In addition, the first detection electrode 24 in the first vibrating body 21 and the third detection electrode 29 in the second vibrating body 26 include a first detection electrode extending portion 34, a jumper wire 53, and a first detection electrode 24. 3 are connected electrically via the three detection electrode extending portions 37.
[0023]
  Next, a method for assembling the angular velocity sensor according to the embodiment of the present invention configured as described above will be described.
[0024]
  First, a tuning fork 32 including a first vibrating body 21, a second vibrating body 26, and a fixing portion 31 is formed by laminating quartz thin plates made of single crystals having different crystal layers.
[0025]
  Next, the first drive electrode 22 on the front surface of the first vibrating body 21, the second drive electrode 23 on the back surface, the first detection electrode 24 on the outer surface, the second detection electrode 25 on the inner surface, Monitor electrode 27 on the front side of the vibrating body 26, the third drive electrode 28 on the back side, the fourth detection electrode 30 on the inner side, the third detection electrode 29 on the outer side, and the third detection electrode 29 on the upper side of the fixing part 31. 1 drive electrode extension 33, first detection electrode extension 34, second detection electrode extension 35, second drive electrode extension 36, third detection electrode extension 37 and first The fourth drive electrode extension 39 is formed on the lower surface of the fixing portion 31, the fourth detection electrode extension 40, the third drive electrode extension 38, the fifth drive electrode extension 41, and the fifth detection. The electrode extending portions 42 are formed by depositing gold.
[0026]
  Next, the first drive terminal 47, the second drive terminal 48, the first detection terminal 49, the second detection terminal 50, and the monitor terminal 51 are respectively inserted into the terminal insertion holes 45 in the base 43. After the insertion, each terminal insertion hole 45 is filled with an insulator 52 made of glass.
[0027]
  Next, after fixing the fixing portion 31 in the tuning fork 32 to the upper surface of the support portion 44 in the base 43, the second drive electrode extending portion 36 in the tuning fork 32 is connected to the first driving terminal 47 in the base 43. The fourth drive electrode extension 39 is formed in the second drive terminal 48, the first detection electrode extension 34 is formed in the first detection terminal 49, and the second detection is performed in the second detection terminal 50. The electrode extension portion 35 is electrically connected to the monitor terminal 51 by the wire bonding via the wire wire 46 made of gold, respectively, to the monitor electrode extension portion 27a.
[0028]
  Next, on the upper surface of the fixing portion 31 in the tuning fork 32, the first detection electrode extension 34 is electrically connected to the third detection electrode extension 37 through the jumper wire 53 by wire bonding.
[0029]
  Next, the operation of the angular velocity sensor according to the first embodiment of the present invention assembled as described above will be described.
[0030]
  An AC voltage having an effective value of about 300 mV is applied to the first drive terminal 47 and the second drive terminal 48 in the base 43. At this time, first, a positive voltage is applied to the second drive electrode 23 in the first vibrating body 21 via the second drive terminal 48 and the fourth drive electrode extension 39 as shown in FIG. When a negative voltage is applied to the first drive electrode 22 via the first drive terminal 47, the second drive electrode extension 36, and the first drive electrode extension 33, the first drive terminal 22 is applied. On the detection electrode 24 side, the direction of the crystal axis and the direction of the charge in the quartz thin plate coincide with each other, and therefore, the direction of the second detection electrode 25 is extended. Therefore, the first vibrating body 21 is inclined toward the second vibrating body 26 as a result. Next, as shown in FIG. 4, the second drive terminal 48 in the first vibrating body 21 is provided via the second drive terminal 48, the fourth drive electrode extension 39, and the third drive electrode extension 38. A negative voltage is applied to the first drive electrode 23, and the first drive electrode 22 is positively applied to the first drive electrode 22 via the first drive terminal 47, the second drive electrode extension 36 and the first drive electrode extension 33. When a voltage is applied, the first detection electrode 24 side contracts because the direction of the crystal axis in the quartz thin plate is opposite to the direction of the charge, while on the second detection electrode 25 side, the crystal is shrunk. Since the direction of the axis coincides with the direction of the charge, it extends, and as a result, the first vibrating body 21 is inclined outward, that is, in the direction opposite to the second vibrating body 26.
[0031]
  Similarly, when an AC voltage is applied to the third drive electrode 28 and the monitor electrode 27 in the second vibrating body 26, the first vibrating body 21 and the second vibrating body 26 are mechanically moved by the fixing portion 31. Since they are connected, the first vibrating body 21 and the second vibrating body 26 bend and vibrate at a speed V in the longitudinal direction of the fixing portion 31 at the natural frequency in the driving direction. Further, when the tuning fork 32 rotates at the angular velocity ω around the longitudinal center axis of the tuning fork 32 in a state where the first vibrating body 21 and the second vibrating body 26 are flexibly vibrating, the first vibrating body. A Coriolis force of F = 2 mvω is generated in 21 and the second vibrating body 26. Due to this Coriolis force, the charge generated in the first detection electrode 24 is transferred to the first detection terminal 49 via the first detection electrode extension 34 and the second detection electrode 25 and the fourth detection electrode 30. The charge generated in the second detection electrode extension part 35 is supplied to the second detection terminal 50, and the charge generated in the third detection electrode 29 is supplied to the third detection electrode extension part 37, the jumper wire. The first detection terminal 49 is input to the first detection terminal 49 via the line 53 and the first detection electrode extension 34, and the output voltages of the first detection terminal 49 and the second detection terminal 50 are differentially amplified. An angular velocity is detected by inputting a differential output voltage to a partner computer (not shown) via a not-shown (not shown).
[0032]
  Here, in the state where the angular velocity is not applied to the angular velocity sensor, when a strong vibration is applied to the angular velocity sensor and the wire wire 46 is detached from the second detection electrode extending portion 35, the embodiment of the present invention is considered. In the angular velocity sensor 1, crosstalk noise due to a high frequency component generated from the first drive electrode 22 is detected by the first detection electrode 24 and the second detection via capacitive coupling of the first vibrating body 21 made of a dielectric. Although transmitted to the electrode 25, since the wire wire 46 is disconnected from the second detection electrode extension portion 35, only the voltage of about 3 V generated at the first detection electrode 24 is applied to the first detection electrode extension portion 34 and the second detection electrode extension portion 34. 1 is input to a differential amplifier (not shown) through one detection terminal 49. In this case, in the first embodiment of the present invention, the gap between the first drive electrode 22 and the first detection electrode 24 and the second detection electrode 25 in the first vibrating body 21 is made substantially the same. As a result, the capacitance generated between the first drive electrode 22 and the first detection electrode 24 and the second detection electrode 25 located on both sides of the first vibrating body 21 is made substantially the same. In a state where no angular velocity is applied to the sensor, if the wire wire 46 that connects the second detection electrode 25 and the second detection terminal 50 in the tuning fork 32 via the second detection electrode extension 35 is disconnected, The crosstalk noise due to the high frequency component generated from the first drive electrode 22 reaches only the first detection electrode 24 through the first vibrating body 21 made of a dielectric, and as a result, crosstalk noise is generated. Yo Since the electric charges generated in the first detection electrode 24 and the second detection electrode 25 do not cancel each other, a voltage is always generated in the second detection electrode 25, whereby the second detection electrode 25 This has the effect of detecting the disconnection of the wire 46 connecting the electrode extension 35 and the second detection terminal 50.
[0033]
  Further, the crosstalk noise due to the high frequency component generated from the first drive electrode extension portion 33 is caused by the first detection electrode extension portion 34 and the second detection electrode extension via the capacitive coupling of the fixing portion 31 made of a dielectric. However, since the wire wire 46 is disconnected from the second detection electrode extension 35, only the voltage of about 1.5 V generated in the first detection electrode extension 34 is the first detection electrode. The signal is input to a differential amplifier (not shown) through the extension 34 and the first detection terminal 49. Then, a total of about 4.5 V added to about 3 V input from the first drive electrode 22 to the first detection electrode 24 is added to the differential amplifier (not shown) via the first detection terminal 49. Will be entered. In this case, in the first embodiment of the present invention, on both sides of the first drive electrode extension portion 33 formed by extending the first drive electrode 22 in the first vibrating body 21 to the fixing portion 31, The first detection electrode extension portion 34 and the second detection electrode extension portion 35 of the first vibrating body 21 are formed to extend so that the gap with the first drive electrode extension portion 33 is substantially the same. As a result, the capacitance generated between the first drive electrode extension 33 and the first detection electrode extension 34 and the second detection electrode extension 35 adjacent to each other is made substantially the same. The electric charge generated by the crosstalk noise from the first drive electrode extension part 33 travels through the fixed part 31 made of a dielectric material and reaches the first detection electrode extension part 34 and the second detection electrode extension part 35. As a result, the second detection electrode 25 in the tuning fork 32 and the electric If the wire 46 that connects the second detection electrode extension 35 and the second detection terminal 50 connected to each other is disconnected, a cross due to a high frequency component generated from the first drive electrode extension 33 The talk noise reaches only the first detection electrode extension portion 34 through the fixed portion 31 made of a dielectric, and thereby the first detection electrode extension portion 34 and the second detection noise are caused by the crosstalk noise. Since the charges generated in the detection electrode extension 35 do not cancel each other in the differential amplifier (not shown), the voltage generated in the first detection electrode extension 34 is always large, and as a result, The effect of being able to reliably detect the disconnection of the wire wire 46 connecting the second detection electrode extension portion 35 electrically connected to the second detection electrode 25 and the second detection terminal 50. Have That.
[0034]
  Next, considering, for example, the case where an angular velocity of 100 deg / sec is loaded on the angular velocity sensor, in the angular velocity sensor according to Embodiment 1 of the present invention, the output voltage is 0 depending on the direction of the loaded angular velocity. .5V or 4.5V. An output signal of a differential amplifier (not shown) is input to a clamp circuit (not shown). The disconnection of the wire 46 is detected when the output signal of the differential amplifier (not shown) becomes 0V or less or 5V or more by a clamp circuit (not shown). As described above, when the wire wire 46 is disconnected from the second detection electrode extension 35, a voltage of about 3 V is generated in the first detection electrode 24, and about 1.V is generated in the first detection electrode extension 34. Since a voltage of 5V is generated, 4.5V including these is input to the differential amplifier (not shown) via the first detection terminal 49. Therefore, even when the output voltage is about 0.5V due to the load of the angular velocity, the sum of 4.5V input to the differential amplifier (not shown) exceeds 5V, so the clamp circuit (FIG. Therefore, it is possible to detect the disconnection of the wire 46 that connects the second detection electrode extension 35 and the second detection terminal 50.
[0035]
  Similarly, in the state where the angular velocity is not applied to the angular velocity sensor, when a strong vibration is applied to the angular velocity sensor and the wire wire 46 is detached from the first detection electrode extension 34, the embodiment of the present invention is considered. In the angular velocity sensor 1, crosstalk noise due to a high frequency component generated from the first drive electrode 22 is detected by the first detection electrode 24 and the second detection via capacitive coupling of the first vibrating body 21 made of a dielectric. Although transmitted to the electrode 25, since the wire wire 46 is disconnected from the first detection electrode extension 34, only the voltage of about 3 V generated at the second detection electrode 25 is applied to the second detection electrode extension 35 and the second detection electrode 35. The signal is input to a differential amplifier (not shown) via two detection terminals 50. Further, the crosstalk noise due to the high frequency component generated from the first drive electrode extension portion 33 is caused by the first detection electrode extension portion 34 and the second detection electrode extension via the capacitive coupling of the fixing portion 31 made of a dielectric. However, since the wire wire 46 is disconnected from the first detection electrode extension portion 34, only the voltage of about 1.5 V generated at the second detection electrode extension portion 35 is applied to the wire wire 46 and the first detection electrode extension portion 34. The signal is input to a differential amplifier (not shown) via two detection terminals 50. Then, a total of about 4 V, which is obtained by adding the voltage of about 1.5 V generated in the second detection electrode extension 35 to the voltage of about 3 V input to the second detection electrode 25 from the first drive electrode 22 described above. The voltage of 5V is input to a differential amplifier (not shown) via the second detection terminal 50.
[0036]
  Furthermore, when the angular velocity is not applied to the angular velocity sensor, a strong vibration is applied to the angular velocity sensor, and the case where the jumper wire 53 is disconnected from the first detection electrode extension 34 is considered. In the angular velocity sensor in the first mode, as shown in FIG. 2, the crosstalk noise due to the high frequency component generated from the third drive electrode 28 is generated through the capacitive coupling of the second vibrating body 26 made of a dielectric. Although it is transmitted to the detection electrode 29 and the fourth detection electrode 30, since the jumper wire 53 is disconnected from the first detection electrode extension 34, only the voltage of about 3V generated at the fourth detection electrode 30 is the first. The signal is input to a differential amplifier (not shown) through the two detection electrode extending portions 35, the wire line 46, and the second detection terminal 50. Further, as shown in FIG. 2, the crosstalk noise due to the high frequency component generated from the third drive electrode extending portion 38 is caused by the fourth detection electrode extending portion 40 via the capacitive coupling of the fixed portion 31 made of a dielectric. On the other hand, the crosstalk noise due to the high frequency component generated from the fifth drive electrode extension 41 is transmitted to the fifth detection electrode extension 42 via the capacitive coupling of the fixed portion 31 made of a dielectric. Since the jumper wire 53 is disconnected from the first detection electrode extension 34, only the voltage of about 1.7 V generated in the first detection electrode extension 34 is applied to the wire 46 and the first detection terminal. 49 to be input to a differential amplifier (not shown). Further, the crosstalk noise due to the high frequency component generated from the second drive electrode extension 36 is transmitted to the third detection electrode extension 37 through the capacitive coupling of the fixed portion 31 made of a dielectric, and the fourth Crosstalk noise due to high frequency components generated from the drive electrode extension 39 is transmitted to the first detection electrode extension 34 via the capacitive coupling of the fixed portion 31 made of a dielectric, but the first detection electrode extension Since the jumper wire 53 is disconnected from the wire 34, only a voltage of about 2.4 V generated in the first detection electrode extension 34 is supplied to the differential amplifier (through the wire wire 46 and the first detection terminal 49. (Not shown). Then, the voltage of about 7.1 V generated by adding the voltage of about 1.7 V generated at the first detection electrode extension 34 to the voltage of about 3 V generated at the fourth detection electrode 30 described above is the total voltage of about 7.1 V. The signal is input to a differential amplifier (not shown) via the first detection terminal 49.
[0037]
  In the angular velocity sensor according to the first embodiment of the present invention, the tuning fork 32 is configured by connecting one end of each of the first vibrating body 21 and the second vibrating body 26 with the fixing portion 31. Even if the tuning fork is constituted by a single columnar or triangular columnar vibrating body, the same effects as those of the first embodiment of the present invention are obtained.
[0038]
  (Embodiment 2)
  Hereinafter, the second embodiment is used to particularly claim the present invention.3And claims6Will be described.
[0039]
  FIG. 5 is a top view of the tuning fork of the angular velocity sensor according to Embodiment 2 of the present invention, and FIG. 6 is a bottom view of the tuning fork of the angular velocity sensor.
[0040]
  In the second embodiment, components having the same configurations as those of the first embodiment are denoted by the same reference numerals, description thereof is omitted, and only differences from the first embodiment are described. .
[0041]
  5 and 6, a comb-shaped first drive having a branch portion 61 formed by extending the first drive electrode 22 of the first vibrating body 21 on the upper surface of the fixing portion 31 of the tuning fork 32. An electrode extension 33a is provided. A comb-shaped first detection electrode extension 34a having a branch 62 formed by extending the first detection electrode 24 is provided on one side of the first drive electrode extension 33a. On the other side, a second detection electrode extending portion 35a having a branch portion 63 formed by extending the second detection electrode 25 is provided. In addition, they cross the branch 61 in the first drive electrode extension 33a and the branch 62 in the first detection electrode extension 34a, and branch in the first drive electrode extension 33a. The part 61 and the branch part 63 in the second detection electrode extension part 35a intersect each other.
[0042]
  Here, in the state where the angular velocity is not applied to the angular velocity sensor, when a strong vibration is applied to the angular velocity sensor and the wire wire 46 is detached from the second detection electrode extending portion 35a, the embodiment of the present invention is considered. In the angular velocity sensor 2, crosstalk noise due to the high frequency component generated from the first drive electrode extension 33 a is caused by the first detection electrode extension 34 a and the second through the capacitive coupling of the fixed part 31 made of a dielectric. However, since the wire wire 46 is disconnected from the second detection electrode extension portion 35a, only the voltage of about 1.3 V generated at the first detection electrode extension portion 34a is transmitted. The signal is input to a differential amplifier (not shown) via the first detection terminal 49. In this case, in the second embodiment of the present invention, the first drive electrode extension portion 33a is formed in a comb shape having the branch portions 61, and the first detection electrode extension portion 34a has the branch portions 62. Since the first driving electrode extending portion 33a and the first detecting electrode extending portion 34a intersect with each other, the branch portion 61 in the first drive electrode extending portion 33a and the branch portion 62 in the first detecting electrode extending portion 34a intersect each other. The branch part 61 in the drive electrode extension part 33a reaches the branch part 62 in the first detection electrode extension part 34a, and as a result, the first fixing electrode 31 is not lengthened. Since the voltage generated in the detection electrode extension 34a can be increased, the disconnection of the wire 46 that connects the second detection electrode extension 35a and the second detection terminal 50 is more reliably detected. Action that can It is those having the results.
[0043]
  Further, in the second embodiment of the present invention, as in the first embodiment of the present invention, the first drive electrode 22 and the first drive electrode extending portion 33a in the first vibrating body 21 are further fixed. The third detection electrode extension portion 37a formed by extending the third detection electrode 29 of the second vibrating body 26 is made to extend along the second drive electrode extension portion 36a formed by extension at 31. In addition, the second drive electrode 23 of the first vibrating body 21 and the third drive electrode extension portion 38a on the lower surface are further extended at the fixing portion 31 to the fourth drive electrode extension portion 39a. A third detection in the second vibrating body 26 is made along the first detection electrode extending portion 34a in the first vibrating body 21 and in the second driving electrode extending portion 36a in the first vibrating body 21. The distance along the electrode extension 37a And the distance between the first drive electrode extension portion 39a of the first vibrating body 21 and the distance between the first detection electrode extension portion 34a of the first vibration body 21 and the gap therebetween. The branch part 64 in the second drive electrode extension part 36a and the branch part 65 in the third detection electrode extension part 37a intersect with each other, and in the fourth drive electrode extension part 39a. The branch part 66 and the branch part 67 in the first detection electrode extension part 34a intersect each other.
[0044]
  In the second embodiment of the present invention, as shown in FIG. 6, the first detection electrode 24 in the first vibrating body 21 is formed to extend so as to be positioned on the lower surface of the fixing portion 31. Comb-shaped third drive having a branch portion 69 formed by extending the second drive electrode 23 of the first vibrating body 21 from the comb-shaped fourth detection electrode extension portion 40a having the branch portion 68. A comb-shaped first portion having a branch portion 70 formed by extending the third drive electrode 28 in the second vibrating body 26 so as to be along the electrode extension portion 38 a and to be located on the lower surface of the fixing portion 31. A comb-shaped fifth detection electrode extension portion 42a having a branch portion 71 formed by extending the third detection electrode 29 of the second vibrating body 26 to the five drive electrode extension portions 41a, And the 3rd drive electrode extension part 3 in the said 1st vibrating body 21 A distance along which the fourth detection electrode extending portion 40a extends along a and a gap between them, and a fifth drive electrode extending portion 41a in the second vibrating body 26 along the fifth detection electrode extending portion 42a. The distance and the gap between them are substantially the same, and the branch 69 in the third drive electrode extension 38a and the branch 68 in the fourth detection electrode extension 40a intersect each other, and the fifth The branch part 70 in the drive electrode extension part 41a and the branch part 71 in the fifth detection electrode extension part 42a cross each other.
[0045]
【The invention's effect】
  As described above, according to the angular velocity sensor of the present invention, the gap between the drive electrode and the detection electrode in the vibrating body of the tuning fork is made substantially the same, so that the static electricity generated between the drive electrode and the detection electrode located on both sides can be obtained. Capacity is almost the sameAt the same time, one drive electrode extension portion formed by extending one drive electrode to the fixed portion of the tuning fork extends along one detection electrode extension portion, and the other drive electrode extends to the fixed portion. The distance between the other drive electrode extension part formed along the other detection electrode extension part and the one drive electrode extension part along the one detection electrode extension part, and the gap between them, The distance between the other drive electrode extension part and the other detection electrode extension part and the gap between them are made substantially the same so that the distance between one drive electrode extension part and one detection electrode extension part And the capacitance generated between the other drive electrode extension and the other detection electrode extension are substantially the same.Therefore, in the state where no angular velocity is applied to the angular velocity sensor, if the wire connecting the one detection electrode and the terminal in the tuning fork is disconnected, the crosstalk noise due to the high frequency component generated from the drive electrode is detected by the other detection electrode. As a result, the electric charges generated in the pair of detection electrodes do not cancel each other due to the crosstalk noise, so that the voltage is always applied to the other detection electrode. As a result, the disconnection of the wire connecting the one detection electrode and the terminal can be detected.In addition, since the electric charge generated by the crosstalk noise travels from the drive electrode extension part to the detection electrode extension part through the fixed part made of a dielectric material, If the wire connecting the sensing electrode and the terminal connected to each other is disconnected, the crosstalk noise caused by the high-frequency component generated from the drive electrode extension is fixed only to the other detection electrode extension. As a result, the charges generated in the pair of detection electrode extensions will not cancel each other due to crosstalk noise, so the voltage generated in the other detection electrode extension is always As a result, it is possible to reliably detect the disconnection of the wire connecting the one detection electrode and the terminal.
[Brief description of the drawings]
FIG. 1 is a perspective view of an angular velocity sensor according to Embodiment 1 of the present invention.
FIG. 2 is a bottom view showing a state in which the tuning fork as the main part is removed from the base.
FIG. 3 is a sectional view showing the same operation
FIG. 4 is a cross-sectional view showing the same operation
FIG. 5 is a top view of a tuning fork in the angular velocity sensor according to the second embodiment of the present invention.
FIG. 6 is a bottom view of the tuning fork which is the main part of the same.
FIG. 7 is a perspective view of a conventional angular velocity sensor.
[Explanation of symbols]
  21 First vibrator
  22 First drive electrode
  23 Second drive electrode
  24 first detection electrode
  25 Second detection electrode
  26 Second vibrator
  27 Monitor electrode
  27a Monitor electrode extension
  28 Third drive electrode
  29 Third detection electrode
  30 Fourth detection electrode
  31 Adhering part
  32 Tuning Fork
  33 First drive electrode extension
  33a Comb-shaped first drive electrode extension part
  34 First detection electrode extension
  34a Comb-shaped first detection electrode extension part
  35 Second detection electrode extension
  35a Comb-shaped second detection electrode extension part
  36 Second drive electrode extension
  36a Comb-shaped second drive electrode extension
  37 Third detection electrode extension
  37a Comb-shaped third detection electrode extension
  38 Third drive electrode extension
  38a Comb-shaped third drive electrode extension
  39 Fourth drive electrode extension
  39a Comb-shaped fourth drive electrode extension
  40 Fourth detection electrode extension
  40a Comb-shaped fourth detection electrode extension
  41 Fifth drive electrode extension
  41a Comb-shaped fifth drive electrode extension
  42 5th detection electrode extension part
  42a Comb-shaped fifth detection electrode extension
  43 base
  46 wire wire
  47 First drive terminal
  48 Second drive terminal
  49 First detection terminal
  50 Second detection terminal
  51 Monitor terminal
  53 Jumper wire
  61, 62, 63, 64, 65, 66, 67 Branch
  68, 69, 70, 71 branch

Claims

A vibration body provided with a pair of drive electrodes and a pair of detection electrodes, a pair of drive electrode extensions formed by extending the pair of drive electrodes and the pair of detection electrodes in the vibration body, and a pair of detection electrodes A tuning fork comprising a fixing portion having a portion, a base to which the fixing portion of the tuning fork is fixed and at least four terminals are inserted, and a drive electrode extending portion at a fixing portion of the terminal and the tuning fork of the base or A wire wire that electrically connects the detection electrode extension, and by making the gap between the drive electrode and the detection electrode in the vibrating body of the tuning fork substantially the same, in addition to substantially the same electrostatic capacitance generated, on both sides of the drive electrodes extending portion which is formed by extending the driving electrodes secured portion of the tuning fork, so that the gap between the drive electrodes extending portion is substantially the same By extending form the detection electrode extending portions, the angular velocity sensors at substantially the same electrostatic capacitance generated between the detection electrode extension portion of the driving electrode extending portion and both sides.

Formed by extending one drive electrode to one of the drive electrodes extended to the fixed portion of the tuning fork and extending the other drive electrode to the fixed portion The distance between the other driving electrode extension part along the other detection electrode extension part and the one driving electrode extension part along the one detection electrode extension part, the gap between them, and the other drive By making the distance along which the other detection electrode extension part extends along the electrode extension part and the gap between them substantially the same, static electricity generated between one drive electrode extension part and one detection electrode extension part is generated. 2. The angular velocity sensor according to claim 1, wherein the capacitance and the capacitance generated between the other drive electrode extension and the other detection electrode extension are substantially the same.

The drive electrode extension is formed in a comb shape having branches, the detection electrode extension is formed in a comb shape having branches, and the branch in the drive electrode extension and the detection electrode extension The angular velocity sensor according to claim 1 or 2, wherein the branch portions in the crossing each other.

A first vibrating body provided with one drive electrode on the upper surface and the lower surface and a pair of detection electrodes on both side surfaces, a monitor electrode provided on the upper surface, provided in parallel with the first vibrating body, and on the lower surface A second vibrating body provided with a drive electrode and further provided with detection electrodes on both side surfaces is connected to one end of the first vibrating body and one end of the second vibrating body. Fixing in which drive electrode, detection electrode, monitor electrode, drive electrode and detection electrode in second vibrator are extended to form drive electrode extension, detection electrode extension and monitor electrode extension, respectively. A tuning fork consisting of a portion, a base in which the fixing portion of the tuning fork is fixed to the upper surface, at least five terminal insertion holes are provided, and at least five terminals are inserted into the terminal insertion holes, and terminals in the base A drive electrode extending portion, a detection electrode extending portion, and a monitor electrode extending portion in the fixing portion of the tuning fork, and a wire wire that electrically connects the driving electrode extending portion, and driving in the first vibrating body and the second vibrating body By making the gap between the electrode and the detection electrode substantially the same, the capacitance generated between the drive electrode and the adjacent detection electrodes in the first and second vibrating bodies is made substantially the same, and the tuning fork In the first vibrating body or the second vibrating body formed by extending the driving electrode to the fixing portion in the second vibrating body, the gap with the driving electrode extending portion is substantially the same on both sides of the driving electrode extending portion. By forming the detection electrode extension in the first vibrating body or the second vibration body, the capacitance generated between the drive electrode extension and the adjacent detection electrode extension is made substantially the same. angular velocity sensors.

The detection electrode extension portion of the first vibrating body extends along the drive electrode extension portion of the first vibrating body formed by extending the drive electrode to the fixing portion, and the driving electrode extends to the fixing portion. The drive electrode extension in the second vibrator is formed along the detection electrode extension in the second vibrator, and the detection electrode extension in the drive electrode extension in the first vibrator. The driving electrode extension and the detection are made substantially the same by the distance along the gap and the gap between them and the distance and the gap along which the detection electrode extension extends along the driving electrode extension in the second vibrating body. The angular velocity sensor according to claim 4 , wherein capacitances generated between the electrode extension portions are substantially the same.

The drive electrode extension is formed in a comb shape having branches, the detection electrode extension is formed in a comb shape having branches, and the branch in the drive electrode extension and the detection electrode extension The angular velocity sensor according to claim 4 or 5, wherein the branch portions in the crossing each other.