JP3642189B2 - Active noise and vibration control device for vehicle - Google Patents

Description

そこで、この（２）式中の「２α」を新たな収束係数αとし、「２βα」を新たな発散抑制係数βとすれば、適応ディジタルフィルタＷのフィルタ係数Ｗ_i の更新式は下記の（３）式のようになる。
【００５５】

ここで、（ｎ），（ｎ＋１）が付く項は、サンプリング時刻ｎ，ｎ＋１，における値であることを表している。また、更新用基準信号Ｒ^T は、理論的には、基準信号ｘを、能動型エンジンマウント２０の電磁アクチュエータ５２及び荷重センサ６４間の伝達関数Ｃをモデル化した伝達関数フィルタＣ＾でフィルタ処理をした値であるが、基準信号ｘの大きさは“１”であるから、伝達関数フィルタＣ＾のインパルス応答を基準信号ｘに同期して次々と生成した場合のそれらインパルス応答波形のサンプリング時刻ｎにおける和に一致する。
【００５６】
また、理論的には、基準信号ｘを適応ディジタルフィルタＷでフィルタ処理して駆動信号ｙを生成するのであるが、基準信号ｘの大きさが“１”であるため、フィルタ係数Ｗ_i を順番に駆動信号ｙとして出力しても、フィルタ処理の結果を駆動信号ｙとしたのと同じ結果になる。
【００５７】
そして、コントローラ２５は、上記のような駆動信号ｙの出力処理及び適応ディジタルフィルタＷの各フィルタ係数Ｗ_i の更新処理を、基準信号ｘの最新のインパルスが生成された時点を基準に開始される固定サンプリング・クロックに同期して実行するようになっている。ここで、基準信号ｘのインパルスの生成に伴ってクリアされ固定サンプリング・クロックに同期してインクリメントされるカウンタをｉ（＝０、１、２、…、Ｌ−１）、サンプリング・クロックの一周期内（サンプリング周期内）に実行されるフィルタ係数Ｗ_j の更新処理を各フィルタ係数Ｗ_j に対して実行するために用いられるカウンタをｊ（＝０、１、２、…、Ｌ−１）とすると、上記（３）式に示した各フィルタ係数Ｗ_j の更新式は、それらｉ，ｊの関係から、具体的には下記のようになる。
【００５８】

但し、Ｌは、基準信号ｘの一周期（制御周期）内に駆動信号ｙとして出力されるフィルタ係数Ｗ_j の個数（タップ数）であり、基準信号ｘの周期Ｔ_x を固定サンプリング・クロックの周期Ｔ_c で割った結果の小数点以下を切り上げた値である。また、Ｌ１は、基準信号ｘの一周期内に駆動信号ｙとして出力されるフィルタ係数Ｗ_j の実際のタップ長の小数点以下まで考慮して求められる整数タップ長であって、基準信号ｘの周期Ｔ_x を固定サンプリング・クロックの周期Ｔ_c で割った結果を小数点第一位で四捨五入した値である。
【００５９】
つまり、コントローラ２５内では、０〜（Ｌ−１）の間で１ずつ増加するカウンタｉのそれぞれに対して、カウンタｊを０から（Ｌ−１）にまで１ずつ増加させる毎に、上記（４）〜（７）のいずれかの更新式に従ってフィルタ係数Ｗ_j が更新されるのである。
【００６０】
そして、上記（４）〜（７）式を実行するためには、上述したタップ数Ｌ及び整数タップ長Ｌ１を常に把握しておかなければならないから、基準信号ｘの周期Ｔ_x の最新の値を常に検出するようになっている。具体的には、基準信号ｘの最新のインパルスとその一つ前のインパルスとの入力間隔を、クロックパルスをカウントする周期測定用タイマによって常時計測し、これにより周期Ｔ_x を取得するようになっている。
【００６１】
また、コントローラ２５は、周期測定用タイマの他に、サンプリング・クロックの周期が経過したことを認識するためのタイマ（サンプリング・クロック測定用タイマ）を有していて、最新の基準信号ｘのインパルスが生成された時点から、サンプリング・クロックの周期と同じ時間を繰り返し測定し、そのサンプリング・クロックに同期して駆動信号ｙを出力するようになっている。
【００６２】
さらに、コントローラ２５は、イグニッションがオンとなって電源が投入された直後には、上記のような駆動信号ｙの出力処理及び適応ディジタルフィルタＷの各フィルタ係数Ｗ_i の更新処理に先駆けて、所定のイニシャライズ処理を実行するようになっている。イニシャライズ処理としては、コントローラ２５を構成するマイクロコンピュータのメモリチェック処理、故障診断処理、Ａ／Ｄ変換器のチェック処理、ＲＡＭの初期化処理、ＥＥＰ−ＲＯＭからのデータ読み出し処理等があるが、ここでは説明の便宜上、イニシャライズ処理Ａ，Ｂ，Ｃ及びＤと呼ぶことにする。
【００６３】
つまり、イグニッションがオンとなって電源が供給されるようになると、コントローラ２５は、決められた手順に従って、先ずはイニシャライズ処理Ａ，Ｂ，Ｃ及びＤを実行するのであるが、本実施の形態では、これらイニシャライズ処理Ａ〜Ｄを、前半処理Ａ，Ｂ及びＣと、後半処理Ｄとに分けている。そして、イグニッションがオンになった直後には、取り敢えず、前半処理Ａ，Ｂ及びＣを実行し、それが完了した時点で待機状態となり、基準信号ｘの新たなインパルスが入力されるまで他の演算処理は実行しないようになっている。この待機状態において基準信号ｘの新たなインパルスが入力されたら、上述した周期測定用タイマをクリアスタートさせるとともに、後半処理Ｄを開始するようになっている。
【００６４】
後半処理Ｄが完了したら、基準信号ｘの新たなインパルスが入力されるまで再び待機状態となり、そのインパルスの入力が確認されたら、そのときの周期測定用タイマの値を保持するとともに、周期測定用タイマを再びクリアスタートさせる。そして、その保持した値に基づいて基準信号ｘの周期Ｔ_x を求め、その周期Ｔ_x から上記タップ数Ｌ及び整数タップ長Ｌ１を演算するようになっている。
【００６５】
なお、イニシャライズ処理Ａ〜Ｄのそれぞれに要する処理時間は、それらの処理の内容から容易に判るものである。そこで、イニシャライズ処理Ａ〜Ｄを前半処理及び後半処理に分ける際には、後半処理に要する処理時間が、前半処理を完了した直後における基準信号ｘの周期Ｔ_x の予測される最短の値よりも短くなるように、前半処理及び後半処理を選定する。例えば、イグニッションスイッチオン（ＩＧＮ．ＯＮ）と略同時にエンジン１７が始動した（ＥＮＧ．ＯＮ）と仮定した場合に、イニシャライズ処理Ａ〜Ｄを全て連続して実行したときのその完了時点におけるエンジン回転数が２００ｒｐｍだとすると、そのときの基準信号ｘの周期（レシプロ４気筒エンジンの場合）は0.15秒（１５０msec）になる。そこで、余裕を見て、後半処理として、処理時間が１００msecとなるように後半処理を選定する。この場合、略１００msecの処理時間を要するイニシャライズ処理がない場合には、トータルの処理時間が１００msec程度になるように複数のイニシャライズ処理を組み合わせて後半処理としてもよい。
【００６６】
また、後述するように、前半処理と後半処理との間に無駄時間Ｔ_e が存在するため、上記のようにイニシャライズ処理Ａ〜Ｄを全て連続して実行したときのその完了時点における基準信号ｘの周期と、それらイニシャライズ処理を前半処理及び後半処理に分けた場合にその後半処理を実行するときの基準信号ｘの周期とは、厳密には一致せず、同じ条件であれば、後者の方が短くなる。しかし、無駄時間Ｔ_e は、本実施の形態では、後述するように基準信号ｘの一周期よりも長くなることはないから、前者と後者との差は、基準信号ｘの隣り合った一周期間の差程度ということになり、これは極小さい。このため、上記のような余裕を見て後半処理を選定すれば、実際に後半処理に要する処理時間が、その時点の基準信号ｘの周期を超えてしまうようなことは容易に回避できるのである。
【００６７】
次に、本実施の形態の動作を説明する。
イグニッションスイッチがオンとなって電源が供給されるようになると、コントローラ２５は、所定の演算処理を実行し、電磁アクチュエータ５２に駆動信号ｙを出力し、能動型エンジンマウント２０に振動を低減し得る能動的な支持力を発生させるようになる。これを、コントローラ２５内で実行される処理の概要を示すフローチャートである図４に従って具体的に説明する。
【００６８】
即ち、電源が供給されると、コントローラ２５は図４の処理を開始し、先ず、そのステップ１０１において、サブルーチン処理としてのイニシャライズ処理Ａが実行され、それが完了したら図４のメインルーチンに復帰してステップ１０２に移行し、サブルーチン処理としてのイニシャライズ処理Ｂが実行され、それが完了したら図４のメインルーチンに復帰してステップ１０３に移行し、サブルーチン処理としてのイニシャライズ処理Ｃが実行される。
【００６９】
一方、イグニッションスイッチがオンになった後に、運転者がエンジンキーをさらに回すと、エンジン１７が始動し、基準信号ｘがコントローラ２５に供給されるようになるが、ステップ１０１〜１０３を実行している間は他の割り込み処理は禁止され、、基準信号ｘの入力も確認されないため、それに応じた処理も実行されない。
【００７０】
そして、ステップ１０３の処理が完了すると、コントローラ２５は割り込み禁止が解除され、ステップ１０４に移行し、基準信号ｘの新たなインパルスが入力されるまで待機状態となる。
【００７１】
つまり、図５に示すように、イグニッションスイッチがオン（ＩＧＮ．ＯＮ）になると、イニシャライズ処理Ａ，Ｂ及びＣが連続して実行され、その間は他の処理は実行されないが、イニシャライズ処理Ｃが完了した時刻ｔ₁ で待機状態になり、基準信号ｘの新たなインパルスが入力されるまで処理は停止する。
【００７２】
図４に戻って、ステップ１０４で基準信号ｘのインパルスが確認されたら、ステップ１０５に移行し、ここで周期測定用タイマがクリアスタートし、次いでステップ１０６に移行し、サブルーチン処理としてのイニシャライズ処理Ｄが実行される。
【００７３】
つまり、図５の例であれば、時刻ｔ₂ において、第一回目の周期演算のためのタイマの計測が開始されるとともに、イニシャライズ処理Ｄの処理が開始されるのである。
【００７４】
このとき、イニシャライズ処理Ｄに要する処理時間は、その時点における基準信号ｘの周期Ｔ_x よりも短いから、サブルーチン処理としてのイニシャライズ処理Ｄが完了して図４のメインルーチンに復帰した時点では、ステップ１０４の判定が「ＹＥＳ」となった後に新たな基準信号ｘのインパルスが生成されているようなことはない。図５の例であれば、ステップ１０４の判定が「ＹＥＳ」となった時刻ｔ₂ から基準信号ｘのその次のインパルスが生成される時刻ｔ₃ に至るまでに、確実にイニシャライズ処理Ｄは完了している。
【００７５】
従って、図４のステップ１０６から１０７に移行し、基準信号ｘの新たなインパルスが入力されるまで待機し、このステップ１０７でインパルスの入力が確認されたときの周期計測用タイマの値は、最新の基準信号ｘの周期Ｔ_x を表していることになる。
【００７６】
そこで、ステップ１０７の判定が「ＹＥＳ」となったら、ステップ１０８に移行し、周期測定用タイマのその時点の値が保存されるとともに、次いでステップ１０９に移行し、周期測定用タイマが再びクリアスタートする。
【００７７】
そして、ステップ１１０に移行し、ステップ１０８で保存した周期測定用タイマの値に基づき、基準信号ｘの周期Ｔ_x が求められ、その周期Ｔ_x と固定サンプリング・クロックの周期Ｔ_c とに基づき、タップ数Ｌ及び整数タップ長Ｌ１が演算される。なお、図４の処理が開始されてからステップ１１０の処理の実行回数が２以上の場合には、後述するカウンタｉの値に基づいてタップ数Ｌを求め、また、そのカウンタｉの値とサンプリング・クロック測定用タイマの値とに基づいて整数タップ長Ｌ１を求めることも可能である。
【００７８】
次いで、ステップ１１１に移行し、カウンタｉが零クリアされた後に、ステップ１１２に移行し、サンプリング・クロック測定用タイマがクリア・スタートされ、そして、ステップ１１３に移行し、適応ディジタルフィルタＷのｉ番目のフィルタ係数Ｗ_i が駆動信号ｙとして出力される。
【００７９】
次いで、ステップ１１４に移行し、カウンタｉが０か否かが判定され、この判定が「ＹＥＳ」の場合には、制御周期（基準信号ｘの周期）が始まった直後であると判断して、一制御周期が始まったことに伴う初期処理を実行すべく、ステップ１１５に移行し、伝達関数フィルタＣ＾に基づき、更新用基準信号Ｒ^T が演算される。なお、ステップ１１５では、基準信号ｘの新たな一周期分の更新用基準信号Ｒ^T がまとめて演算される。
【００８０】
ステップ１１４の判定が「ＮＯ」の場合並びにステップ１１５の処理を終えた場合には、ステップ１１６に移行し、残留振動信号ｅが読み込まれる。そして、ステップ１１７に移行して、カウンタｊが零クリアされる。
【００８１】
そして、ステップ１１８に移行し、カウンタｉ及びｊに基づいて上記（４）〜（７）式のいずれかが選択され、そのときのカウンタｊに対応した適応ディジタルフィルタＷのフィルタ係数Ｗ_j が更新される。
【００８２】
次いで、ステップ１１９に移行し、基準信号ｘの次のインパルスが入力されているか否かを判定し、ここで基準信号ｘが入力されていないと判定された場合には、適応ディジタルフィルタＷの次のフィルタ係数の更新又は駆動信号ｙの出力処理を実行すべく、ステップ１２０に移行する。
【００８３】
ステップ１２０では、全フィルタ係数Ｗ_j に対する更新演算が完了しているか否か、つまりカウンタｊがタップ数Ｌ（正確には、カウンタｊは０からスタートするため、タップ数Ｌから１を減じた値）に達しているか否かが判定され、この判定が「ＮＯ」の場合には、ステップ１２１に移行し、カウンタｊをインクリメントした後に、ステップ１１８に戻って上述した処理を繰り返し実行する。
【００８４】
しかし、ステップ１２０の判定が「ＹＥＳ」の場合には、適応ディジタルフィルタＷのフィルタ係数Ｗ_j のうち、駆動信号ｙとして必要な数のフィルタ係数の更新処理が完了したと判断できるから、ステップ１２２に移行してカウンタｉをインクリメントする。次いでステップ１２３に移行し、上記ステップ１１２でクリア・スタートさせたサンプリング・クロック測定用タイマの値が固定サンプリング・クロックの周期Ｔ_c に達するまで待機した後、上記ステップ１１２に戻って上述した処理を繰り返し実行する。
【００８５】
一方、ステップ１１９で基準信号ｘの新たなインパルスが入力されたと判断された場合には、ステップ１０８に戻って、上述した処理を繰り返し実行する。
このような図４の処理を繰り返し実行する結果、コントローラ２５から能動型エンジンマウント２０の電磁アクチュエータ５２に対しては、基準信号ｘが入力された時点から、固定サンプリング・クロックに同期して、適応ディジタルフィルタＷのフィルタ係数Ｗ_i が順番に駆動信号ｙとして供給される。
【００８６】
この結果、励磁コイル５２ｂに駆動信号ｙに応じた磁力が発生するが、磁路形成部材７８Ｂには、すでに永久磁石５２ｃによる一定の磁力が付与されているから、その励磁コイル５２ｂによる磁力は永久磁石５２ｃの磁力を強める又は弱めるように作用すると考えることができる。このように、永久磁石５２ｃの磁力が強まったり弱まったりすると、可動部材７８が正逆両方向に変位し、可動部材７８が変位すれば、主流体室８４の容積が変化し、その容積変化によって支持弾性体３２の拡張ばねが変形するから、この能動型エンジンマウント２０に正逆両方向の能動的な支持力が発生するのである。
【００８７】
そして、駆動信号ｙとなる適応ディジタルフィルタＷの各フィルタ係数Ｗ_i は、ＳＦＸアルゴリズムに従った上記（４）〜（７）式によって逐次更新されるため、ある程度の時間が経過して適応ディジタルフィルタＷの各フィルタ係数Ｗ_i が最適値に収束した後は、駆動信号ｙが能動型エンジンマウント２０に供給されることによって、エンジン１７から能動型エンジンマウント２０を介して車体１８側に伝達されるアイドル振動やこもり音振動が低減されるようになる。
【００８８】
さらに、本実施の形態では、図５にも例示したように、コントローラ２５に電源が投入された直後のイニシャライズ処理を、前半処理Ａ〜Ｃと後半処理Ｄとに分けるとともに、その後半処理Ｄを、第一回目の周期測定タイマによる測定処理と並列に実行するようにしているから、無駄時間Ｔ_e を大幅に短縮できるという利点がある。
【００８９】
つまり、図６の示した従来例では、イニシャライズ処理Ａ〜Ｄを連続して実行する構成であるため、無駄時間Ｔ_e は、最小でも基準信号ｘの周期Ｔ_x を超え、最大では周期Ｔ_x の二倍近くにも鳴るのに対し、図５に示した本実施の形態であれば、無駄時間Ｔ_e は、最大でも基準信号ｘの周期Ｔ_x 未満（イニシャライズ処理Ｃの完了の直前にインパルスが入力された場合）であり、タイミングが合えば（イニシャライズ処理Ｃの完了の直後にイニシャライズが入力された場合）、無駄時間Ｔ_e は略零になる。その結果、本来の振動低減制御が実行されるまでの時間を、従来に比べて短縮できるから、それだけ早期のうちに振動低減効果が発揮できるようになる。
【００９０】
なお、能動型エンジンマウント２０内の流体共振系の共振周波数を２０Ｈｚに調節している結果、５〜１５Ｈｚの振動であるエンジンシェイク発生時にもある程度の減衰力がこの能動型エンジンマウント２０で発生するため、エンジン１７側で発生したエンジンシェイクが能動型エンジンマウント２０によってある程度減衰されるとともに、図示しない他の流体封入式エンジンマウント等によってもエンジンシェイクは減衰されるから、これによっても車体１８側の振動レベルが低減される。
【００９１】
ここで、本実施の形態では、エンジン１７が振動源に対応し、能動型エンジンマウント２０の荷重センサ６４以外の部分が制御振動源に対応し、荷重センサ６４が残留振動検出手段に対応し、パルス信号生成器１９が基準信号生成手段に対応し、コントローラ２５が制御手段に対応し、図４のステップ１０４、１０５、１０７、１１０、１１９及びコントローラ２５内の周期測定用タイマが周期取得手段に対応する。
【００９２】
なお、上記実施の形態においては、残留振動を能動型エンジンマウント２０に内蔵した荷重センサ６４によって検出しているが、これに限定されるものではなく、例えば車室内の乗員足元位置にフロア振動を検出する加速度センサを配設し、その加速度センサの出力信号を残留振動信号ｅとしてもよい。
【００９３】
そして、上記実施の形態においては、本発明における車両用能動型騒音振動制御装置をエンジン１７から車体１８に伝達される振動を低減する車両用能動型振動制御装置に適用した場合について説明したが、本発明の対象はこれに限定されるものではなく、騒音源としてのエンジン１７から車室内に伝達される騒音を低減する車両用能動型騒音制御装置であってもよく、かかる車両用能動型騒音制御装置とする場合には、車室内に制御音を発生するための制御音源としてのラウドスピーカと、車室内の残留騒音を検出する残留騒音検出手段としてのマイクロフォンとを設け、上記実施の形態と同様の演算処理を実行すれば、上記実施の形態と同様の作用効果を得ることができる。
【００９４】
さらに、上記各実施の形態では、駆動信号ｙを生成するアルゴリズムとしてＳＦＸアルゴリズムを適用しているが、適用可能なアルゴリズムはこれに限定されるものではなく、例えば、通常のＬＭＳアルゴリズム、Ｆｉｌｔｅｒｅｄ−Ｘ ＬＭＳアルゴリズム等であってもよい。
【図面の簡単な説明】
【図１】一実施の形態を示す車両の概略構成図である。
【図２】能動型エンジンマウントの一例を平面視で示した図である。
【図３】図２のＡ−Ａ矢視断面及びＢ−Ｂ矢視断面図である。
【図４】振動低減処理の概要を示すフローチャートである。
【図５】実施の形態の動作を説明するタイムチャートである。
【図６】従来例の動作を説明するタイムチャートである。
【符号の説明】
１７ エンジン（振動源）
１８ 車体
１９ パルス信号生成器（基準信号生成手段）
２０ 能動型エンジンマウント（制御振動源）
２５ コントローラ（制御手段）
５２ 電磁アクチュエータ
６４ 荷重センサ（残留振動検出手段）[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an active noise / vibration control device for a vehicle which generates active control sound or control vibration to reduce noise or vibration, and in particular, can further improve control characteristics immediately after engine startup. It is what I did.
[0002]
[Prior art]
As this type of conventional technology, for example, there is one disclosed in Japanese Patent Laid-Open No. 9-319380 previously proposed by the present applicant as an embodiment. That is, the prior art described in the column of the embodiment of the publication relates to an active vibration control device for a vehicle using an adaptive algorithm such as an LMS algorithm, and more specifically, an adaptive digital filter having a variable filter coefficient. As an algorithm for updating the filter coefficient of the adaptive digital filter, a synchronous Filtered-XLMS algorithm (hereinafter referred to as SFX algorithm) is applied, and vibration generated in the engine according to the SFX algorithm The control vibration for reducing the noise is generated.
[0003]
When an adaptive algorithm such as the above SFX algorithm is executed, it is necessary to grasp the period of noise or vibration generated, but the period of noise or vibration generated in the engine changes with the engine speed. The noise or vibration cycle must always be detected and understood. Therefore, in the conventional apparatus, for example, in the case of a reciprocating four-cylinder engine, every time the crankshaft rotates 1/2, combustion occurs once and causes vibration. A reference signal composed of a synchronized impulse train is generated, and the period of noise or vibration is acquired based on the input interval between the latest impulse of the reference signal and the previous impulse.
[0004]
In the configuration in which the period of noise or vibration is detected based on the impulse input interval as described above, the period detected when the reference signal impulse is generated is actually the previous impulse. Strictly speaking, it does not represent the period after the latest impulse of the reference signal is generated. However, in the case of an engine that rotates at a relatively high speed, the input interval between the latest impulse of the reference signal and the previous impulse is the input interval between the latest impulse of the reference signal and the next impulse. Since it is very close and it can be considered that both are substantially the same, the accuracy of the vibration reduction control does not greatly decrease for that reason.
[0005]
[Problems to be solved by the invention]
Certainly, detecting the period of noise or vibration based on the input interval of impulses as described above does not cause a major problem during the execution of vibration reduction control. According to the above, it was found that there is a point to be improved in the control contents immediately after the ignition switch is turned on and the controller is turned on.
[0006]
That is, FIG. 6 shows the calculation processing status in the controller immediately after the driver inserts the engine key in the vehicle and rotates it to turn on the ignition switch (IGN.ON). As shown in FIG. 6, in the vehicle, when the ignition switch is turned on, the controller is turned on, thereby enabling arithmetic processing. When the controller is powered on, initialization processing is executed prior to vibration reduction control. In the example of FIG. 6, the initialization processes A, B, C, and D are executed in this order as the initialization process.
[0007]
On the other hand, when the driver further rotates the engine key from the ignition-on position to start the engine (ENG.ON), the cell motor starts and cranks, and then the engine starts. The time from when the ignition switch is turned on until the engine is started (IGN.ON to ENG.ON) is generally very short although it depends on the driver's habit. For this reason, as shown in FIG. 6, the reference signal x formed of an impulse train is generated during the initialization process, but other interrupt processes are prohibited during the initialization process, and the reference signal x Is not monitored, when all the initialization processes are completed, in the example of FIG. 6, the time t when the initialization process D is completed. ₁ Only then will the input of the reference signal x be monitored. Then, the first period calculation of noise or vibration is time t ₁ The time t when the second impulse of the reference signal x is generated later ₂ Therefore, the noise or vibration reduction control is actually started at time t. ₂ After that.
[0008]
That is, the initialization process is performed at time t. ₁ In spite of being completed, the control sound and the control vibration are actually generated after at least two impulses are input as the reference signal x. In some cases, the reference signal x After the time of approximately two cycles elapses, during that time, the dead time T during which the CPU is in a standby state _e It becomes.
[0009]
Since the engine speed at the time of cranking is normally about 100 to 200 rpm, in the case of a reciprocating four-cylinder engine, the cycle of the reference signal x at the time of cranking is about 0.15 to 0.3 seconds. Therefore, the dead time T between the end of the initialization process and the actual start of noise or vibration reduction control _e Can be considered to exceed 0.15 seconds at the minimum and 0.5 seconds at the maximum. _e The longer the is, the higher the possibility of discomfort to the occupant.
[0010]
The present invention has been made paying attention to such problems to be solved by the conventional technology, and provides an active noise vibration control device for a vehicle that can reduce the dead time as described above. It is an object.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 makes noise or vibration generated by interfering with noise or vibration emitted from an engine and control sound or control vibration emitted from a control sound source or a control vibration source. The vibration is reduced, and the period of noise or vibration generated from the engine is acquired based on the input interval of the pulse signal synchronized with the rotation of the crankshaft of the engine, and the acquired period In an active noise / vibration control device for a vehicle that is used for arithmetic processing after the latest pulse signal is generated, initialization processing immediately after the power is turned on When the first half of the process is completed, the initialization process is in a standby state. When the input of the pulse signal is confirmed during the standby, the initialization by the timer for acquiring the period of the noise or vibration and the initialization are performed. Based on the measured value of the timer when the second half of the process is started and the input of the new pulse signal is confirmed after the completion of the second half of the process, Noise or vibration The first cycle is acquired It was to so.
[0012]
In order to achieve the above object, the invention according to claim 2 includes a control sound source or a control vibration source capable of generating a control sound or a control vibration that interferes with a noise or vibration emitted from an engine, A residual noise detecting means or residual vibration detecting means for detecting noise or vibration and outputting it as a residual noise signal or residual vibration signal, and a reference signal for generating a reference signal composed of an impulse train synchronized with the noise or vibration generated from the engine Generating means, and control means for generating and outputting a drive signal for driving the control sound source or control vibration source so as to reduce the noise or vibration after the interference based on the residual noise signal or residual vibration signal and the reference signal; The control means takes the period of the noise or vibration based on the latest impulse of the reference signal and the input interval of the previous impulse. Active noise for a vehicle having a period acquisition means for performing the calculation processing after the latest impulse of the reference signal is generated, using the period of the noise or vibration acquired by the period acquisition means. In the vibration control device, the control means includes an initialization process immediately after the power is turned on. When the first half of the processing is completed, a standby state is entered, and when the input of a new impulse of the reference signal is confirmed during the standby, the measurement by the timer for acquiring the period of the noise or vibration and the initialization are performed. Based on the measured value of the timer when the input of a new impulse of the reference signal is confirmed after completion of the latter half of the process, Noise or vibration Get first cycle I tried to do it.
[0014]
And claims 3 The invention according to claim 1 1 or 2 In the vehicular active noise and vibration control apparatus according to the invention, the processing time required for the latter half of the initialization process is determined immediately after the first half of the initialization process is completed. Noise or vibration cycle The latter treatment was selected so as to be shorter.
[0015]
Here, in the invention according to claim 1, since the first acquisition process of the noise or vibration cycle is executed during the execution of the initialization process immediately after the power is turned on, the initialization process is completed. Compared to the case where the periodic income process is started later, the noise or vibration reduction process is started earlier.
[0016]
Further, in the invention according to claim 2, since the control means executes the first acquisition process of the cycle of noise or vibration during the execution of the initialization process immediately after the power is turned on, the initialization process is performed. Compared with the case where the periodic income processing is started after the completion of the above, the noise or vibration reduction processing is started earlier.
[0017]
That is, Claim 1, 2 In the invention pertaining to , Lee The initialization process is divided into the first half and the second half, and when the first half of the process is completed, it is temporarily in a standby state. During such waiting, Pulse signal or Monitor whether a new impulse of the reference signal has been input and Pulse signal or When the impulse input is confirmed, the standby state is released.
[0018]
When the standby state is released , Zhou Timer for period acquisition But start You And the second half of the initialization process But Start. In other words, since the latter half of the initialization process and the measurement process by the period acquisition timer proceed in parallel, one process is completed after the latter half of the initialization process is completed. Pulse signal or The period of noise or vibration can be acquired from the measured value of the timer when the impulse input is confirmed.
[0019]
And claims 3 In the invention according to the present invention, during the execution of the second half of the initialization process, New pulse signal or Since the possibility that a new impulse of the reference signal is generated can be eliminated, after completion of the second half of the initialization process, one Pulse signal or The period of noise or vibration can be reliably obtained from the measured value of the timer when the input of the impulse is confirmed.
[0020]
And this claim 3 In order to realize the invention according to the above, it is necessary to divide all initialization processes into the first half and the second half so as to satisfy the above-mentioned requirements. For example, taking the invention according to claim 2 as an example It becomes as follows.
[0021]
That is, the relationship between the elapsed time from the time of engine start (ENG.ON) and the period of the reference signal x (the input interval between two adjacent impulses) is determined in detail by conducting an experiment in advance for each engine type. Assuming that the engine is started almost at the same time as when the ignition switch is turned on (IGN.ON), and when the initialization process is continuously performed after the ignition switch is turned on, the initialization process is completed. The period of the reference signal x is determined from the above correspondence, and all the initializations are performed so that the time required for the latter half of the initialization process is shorter than the determined period of the reference signal x with a certain margin. What is necessary is just to divide processing into the first half and the second half.
[0022]
【The invention's effect】
According to the present invention, since the first acquisition process of the period of noise or vibration is executed during the execution of the initialization process immediately after the power is turned on, the period income process is started after the initialization process is completed. Compared to the case, since the noise or vibration reduction process can be started earlier, there is an effect that the possibility of giving the passenger discomfort can be reduced.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 to FIG. 5 are diagrams showing an embodiment of the present invention. FIG. 1 is an application of an active vibration control device for a vehicle which is an embodiment of an active noise vibration control device for a vehicle according to the present invention. 1 is a schematic side view of a vehicle.
[0024]
First, the configuration will be described. An engine 17 mounted horizontally is supported by a vehicle body 18 including a suspension member and the like via an active engine mount 20 disposed rearward in the vehicle body front-rear direction. Actually, a plurality of engine mounts that generate a passive support force according to the relative displacement between the engine 17 and the vehicle body 18 are interposed between the engine 17 and the vehicle body 18 in addition to the active engine mount 20. ing. As a passive engine mount, for example, a normal engine mount that supports a load with a rubber-like elastic body, or a known fluid-filled mount in which a fluid is sealed inside a rubber-like elastic body so that a damping force can be generated. An insulator or the like can be applied.
[0025]
FIG. 2 is a plan view showing the upper structure of the active engine mount 20 connected via a bracket (not shown) fixed to the engine 17, and protrudes upward from the engine side connecting member 30. The two connecting bolts 30a are inserted into the above-described bracket insertion holes from below, and the nuts are screwed to fix the upper end of the engine 17 to the engine 17. Reference numeral 60 denotes a rebound restricting member. The rebound restricting member 60 is orthogonal to a line connecting the two connecting bolts 30a and extends in an arch shape above the engine side connecting member 30. It is fixed to the case 43 and is located above the rebound stopper 31 made of a rubber elastic body fixed to the upper surface of the engine side connecting member 30.
[0026]
FIG. 3 shows the internal structure of the active engine mount 20 shown in the cross-sectional view of FIG. 2, and the cross-section taken along the line AA along the line connecting the two connecting bolts 30 a of FIG. 3 (hereinafter referred to as a mount shaft) P in FIG. ₁ Is shown on the right side as a boundary, and a cross section taken along line B-B in a direction orthogonal to the line connecting the two connecting bolts 30a in FIG. ₁ Is shown on the right as a boundary.
[0027]
This active engine mount 20 incorporates mount parts such as an outer cylinder 34, an intermediate cylinder 36, an orifice component member 37, a support elastic body 32 and the like in a device case 43, and a partition wall of a fluid chamber 84 is formed below these mount parts. A device that incorporates an electromagnetic actuator 52 that displaces a movable member 78 that is elastically supported while forming a part in a direction in which the volume of the fluid chamber 84 changes, and a load sensor 64 that detects a vibration state of a vehicle body member (not shown). More specifically, the engine-side connecting member 30 described above is formed with a rounded bottom edge 30g and a mount shaft P. ₁ The 1st hole 30c is formed in the position in alignment with. Further, the connecting bolt 30 a that is fitted into the engine connecting member 30 from the lower side and faces upward has a head portion 30 d protruding from the lower surface of the engine side connecting member 30. Here, the outer peripheral edge portion of the head portion 30d is rounded.
[0028]
A hollow cylindrical body 30b having an inverted trapezoidal cross section is fixed to the lower surface of the engine side connecting member 30. The hollow cylinder 30b has a second hole 30e formed at a position close to the connecting bolt 30a, and a mount shaft P ₁ A third hole 30f is formed in the lower surface along the line. In addition, the hole is not formed in the position spaced apart from the connection bolt 30a of this hollow cylinder 30b.
[0029]
A rubber support elastic body 32 is fixed to the lower surface side of the engine side connecting member 30 by vulcanization so as to cover the inside of the hollow cylinder 30b and the lower side of the engine side connecting member 30. .
[0030]
That is, the support elastic body 32 is a rubber elastic body having a diameter expanded downward from the engine side connecting member 30 side, and a cavity 32a having a mountain-shaped cross section is formed on the inner surface. As shown on the left side of FIG. 3, the outer peripheral surface of the support elastic body 32 at a portion away from the connecting bolt 30 a is continuous with the rebound stopper 31 while covering the outer peripheral portion of the engine side connecting member 30. On the other hand, as shown on the right side of FIG. 3, the support elastic body 32 close to the connection bolt 30a is formed with a covering portion 32b that covers the entire region of the head 30d of the connection bolt 30a, and the head 30d. The outer periphery of the lower position has a shape that is greatly recessed inward (hereinafter referred to as a recessed outer peripheral portion indicated by reference numeral 32c). Further, the inner surface of the support elastic body 32 facing the concave outer peripheral portion 32c while forming the above-described hollow portion 32a also has a shape bulging inwardly (hereinafter referred to as a bulging inner peripheral portion indicated by reference numeral 32d). ). The thickness of the portion of the supporting elastic body 32 in the vicinity of the connecting bolt 30a is the thickness of the portion away from the connecting bolt 30a by providing the bulging inner peripheral portion 32d facing the concave outer peripheral portion 32c. It is set to be almost the same as the thickness.
[0031]
And the lower end part of the thin support elastic body 32 has a mount axis P ₁ Is coupled to the inner peripheral surface of the intermediate cylinder 36 coaxially with the hollow cylinder 30b in the vibrating body support direction by vulcanization adhesion.
[0032]
The intermediate cylinder 36 is a member in which a small diameter cylinder part 36c is continuously formed between an upper end cylinder part 36a and a lower end cylinder part 36b having the same outer diameter, and an annular recess is provided on the outer periphery. Although not shown, an opening is formed in the small diameter cylindrical portion 36c, and the inner side and the outer side of the intermediate cylindrical body 36 communicate with each other through the opening.
[0033]
An outer cylinder 34 is fitted on the outer side of the intermediate cylinder 36, and the outer cylinder 34 has an inner peripheral diameter that is the same as the outer diameters of the upper end cylinder part 36a and the lower end cylinder part 36b of the intermediate cylinder 36, and the shaft This is a cylindrical member whose length in the direction is set to the same dimension as that of the intermediate cylinder 36. In addition, an opening 34a is formed in the outer cylinder 34, and the outer periphery of a diaphragm 42 made of a rubber thin film elastic body is coupled to the opening edge of the opening 34a to close the opening 34a. It bulges toward the inside of the outer cylinder 34.
[0034]
When the outer cylinder 34 having the above-described configuration is externally fitted to the intermediate cylinder 36 so as to surround the annular recess, an annular space is defined in the circumferential direction between the outer cylinder 34 and the intermediate cylinder 36, and a diaphragm is formed in the annular space. 42 is arranged in a bulging state. A cylindrical orifice component member 37 is fitted inside the intermediate cylinder 36.
[0035]
The orifice component member 37 includes a minimum diameter cylindrical portion 37a formed to have a diameter smaller than that of the small diameter cylindrical portion 36c of the intermediate cylindrical body 36, and an upper annular portion facing radially outward at the upper and lower end portions of the minimum diameter cylindrical portion 37a. 37b and a lower annular portion 37c are formed, and an annular space is provided between the intermediate cylindrical body 36 and a position surrounded by the minimum diameter cylindrical portion 37a and the upper and lower annular portions 37b and 37c. Moreover, the 2nd opening part 37d is formed in a part of minimum diameter cylinder part 37a. Here, the upper annular portion 37b is located below the support elastic body 32, but as shown on the right side of FIG. 2, it is located below the support elastic body 32 close to the connecting bolt 30a. Upper annular part 37b ₁ Is formed with a thin wall and provided with a recess, and is opposed to a position away from the bulging inner peripheral portion 32d of the support elastic body 32.
[0036]
The device case 43 has an upper end caulking portion 43a having a circular opening smaller in diameter than the outer peripheral diameter of the upper end cylindrical portion 36a at the upper end portion, and the shape of the case main body that is continuous with the upper end caulking portion 43a. , A member having a cylindrical shape in which the inner peripheral diameter is the same as the outer peripheral diameter of the outer cylinder 34 and continues to the lower end opening (the lower end opening is indicated by a broken line in FIG. 2). After the completion, the lower end opening is caulked inward in the radial direction to form a caulking portion indicated by a solid line in FIG.
[0037]
Then, the outer cylinder 34 in which the support elastic body 32, the intermediate cylinder 36, the orifice component member 37, and the diaphragm 42 are integrated is fitted inside from the lower end opening of the device case 43, and is externally attached to the lower surface of the upper end caulking section 43a. When the upper ends of the cylinder 34 and the intermediate cylinder 36 are brought into contact with each other, they are arranged in the upper part in the apparatus case 43. At this time, an air chamber 42c is defined in a portion surrounded by the inner peripheral surface of the device case 43 and the diaphragm 42. An air hole 43a is formed at a position facing the air chamber 42c. The air chamber 42c and the atmosphere communicate with each other through 43a.
[0038]
A cylindrical spacer 70 is fitted in the lower part of the device case 43, a movable member 78 is disposed in the upper part of the spacer 70, and an electromagnetic actuator 52 is disposed in the lower part of the spacer 70. . The spacer 70 has a substantially cylindrical diaphragm 70c formed of a cylindrical upper cylindrical body 70a, a cylindrical lower cylindrical body 70b, and a rubber thin film elastic body vulcanized and bonded between the upper and lower ends of the cylindrical bodies. It consists of and.
[0039]
The electromagnetic actuator 52 includes a cylindrical yoke 52a having an outer appearance, an annular exciting coil 52b disposed on the upper end surface side of the yoke 52a, and a permanent magnet having a magnetic pole fixed vertically at the center of the upper surface of the yoke 52a. 52c. The yoke 52a includes an annular first yoke member 53a and a second yoke member 53b in which a permanent magnet 52c is fixed to the central cylindrical portion.
[0040]
The diaphragm 70c between the upper and lower cylinders 70a and 70b bulges toward a recess 52d formed on the outer periphery of the yoke 52a.
A load sensor 64 is interposed between the lower surface of the yoke 52a and the lid member 62 provided with the vehicle body side connecting bolt 60 in order to detect residual vibration necessary for vibration reduction control. As the load sensor 64, a piezoelectric element, a magnetostrictive element, a strain gauge, or the like is applicable, and the detection result of this sensor is supplied to the controller 25 as a residual vibration signal e as shown in FIG. Yes.
[0041]
On the other hand, above the electromagnetic actuator 52, a seal ring 72 for fixing a seal member, a support ring 74 that supports an outer peripheral portion of a leaf spring 82 to be described later from the lower end, a permanent magnet 52c of the electromagnetic actuator 52, and A gap holding ring 76 that sets a gap H between the movable members 78 is disposed. The outer diameters of the seal ring 72, the support ring 74, and the gap retaining ring 76 are set to the same dimensions as the inner diameter of the upper cylinder 70a of the spacer 70 described above, and the upper cylinder protrudes upward from the yoke 52a. The seal ring 72, the support ring 74, and the gap retaining ring 76 are all fitted in the body 70a. A movable member 78 is arranged inside the seal ring 72, the support ring 74, and the gap retaining ring 76 so as to be displaceable in the vertical direction.
[0042]
The movable member 78 is a member composed of a disk-shaped partition wall forming member 78A and a magnetic path forming member 78B formed in a disk shape larger in diameter than the partition wall forming member 78A, and is far from the electromagnetic actuator 52. A bolt hole 80a is formed in the axial center of the partition wall forming member 78A positioned on the side, and the movable member bolt 80 penetrating the magnetic path forming member 78B close to the electromagnetic actuator 52 is screwed into the bolt hole 80a, thereby forming the partition wall. The member 78A and the magnetic path forming member 78B are integrally connected.
[0043]
A constricted portion 79 that is continuous in a ring shape is defined between the partition forming member 78A and the magnetic path forming member 78B, and a leaf spring 82 for elastically supporting the movable member 78 is accommodated in the constricted portion 79. ing. In other words, the leaf spring 82 is a disk-shaped member having a hole at the center, and the inner periphery of the leaf spring 82 is supported at the free end from the lower center of the back surface of the partition wall forming member 78A. A spring support portion 74a of the support ring 74 supports the outer peripheral portion of the support ring 74 from below, so that the movable member 78 is elastically supported by the device case 43 via the leaf spring 82.
[0044]
The partition wall forming member 78A is a member in which the thickness of the partition wall portion 80c facing the fluid chamber 84 is reduced, and an annular rib 80b protruding upward from the outer periphery of the partition wall portion 80c is formed. A fluid chamber 84 is formed by the upper surface of the partition wall forming member 78 </ b> A, the lower surface of the support elastic body 32, and the inner peripheral surface of the orifice component member 37, and the fluid is sealed in the fluid chamber 84.
[0045]
Further, in order to prevent fluid from leaking from the fluid chamber 84 to the constricted portion 79 side that accommodates the leaf spring 82, there is a rubber-like elasticity between the outer periphery of the partition forming member 78A and the inner periphery of the seal ring 72. A ring-shaped seal member 86 composed of a body is fixed, and the relative deformation in the vertical direction of the movable member 78 with respect to the seal ring 72 and the device case 43 is allowed by elastic deformation of the seal member 86.
[0046]
Next, the vibration input damping action of the active engine mount 20 of this embodiment will be briefly described. In the active engine mount 20 of the present embodiment, the hollow portion 32a of the support elastic body 32 and the axial center space of the orifice component member 37 communicate with each other, and the axial center space of the orifice component member 37 and the orifice component member 37 and the intermediate cylinder body. 36 is communicated via the second opening 37d, and the annular space and the space where the diaphragm 42 bulges communicate via the opening formed in the intermediate cylinder 36. A fluid such as ethylene glycol is sealed in the communication path from the hollow portion 32a of the support elastic body 32 to the space where the diaphragm 42 swells.
[0047]
When the communication path from the cavity 32 a of the support elastic body 32 to the annular space between the orifice constituent member 37 and the intermediate cylinder 36 is a main fluid chamber 84, the vicinity of the opening formed in the intermediate cylinder 36 is defined. A fluid resonance system is formed in which a region surrounded by the diaphragm 42 is formed as an orifice, and the region surrounded by the diaphragm 42 is opposed to the opening. The characteristics of the fluid resonance system, that is, the characteristics determined by the mass of the fluid in the orifice, the expansion direction spring of the support elastic body 32, and the expansion direction spring of the diaphragm 42, are generated when idling vibration occurs while the vehicle is stopped, that is, 20 to When the engine mounts 20 </ b> A and 20 </ b> B are vibrated at 30 Hz, they are adjusted so as to exhibit a high dynamic spring constant and a high damping force.
[0048]
On the other hand, the excitation coil 52b of the electromagnetic actuator 52 generates a predetermined electromagnetic force according to a drive signal y that is a current supplied from the controller 25 through, for example, a harness. The controller 25 includes a microcomputer, a necessary interface circuit, an A / D converter, a D / A converter, an amplifier, a storage medium such as a ROM, a RAM, and the like, and can actively reduce vibrations generated by the engine 17. A drive signal y for the active engine mount 20 is generated and output so that a dynamic support force is generated in the active engine mount 20.
[0049]
As described above, the active engine mount 20 includes the load sensor 64, detects the vibration state of the vehicle body 18 in the form of a load and outputs it as a residual vibration signal e, and the residual vibration signal e interferes. For example, a signal representing the vibration afterward is supplied to the controller 25 through a harness.
[0050]
Here, the idle vibration and the booming noise vibration generated in the engine 17 are mainly caused by the engine vibration of the secondary component of engine rotation being transmitted to the vehicle body 18 in the case of a reciprocating four-cylinder engine, for example. If the drive signal y is generated and output in synchronization with the secondary rotation component, the vibration on the vehicle body side can be reduced. Therefore, in the present embodiment, an impulse signal is generated in synchronization with the rotation of the crankshaft of the engine 17 (for example, in the case of a reciprocating four-cylinder engine, one is generated every time the crankshaft rotates 180 degrees), and the reference signal x The reference signal x is supplied to the controller 25.
[0051]
The controller 25 calculates the drive signal y for the active engine mount 20 by executing the SFX algorithm, which is one of the adaptive algorithms, based on the supplied residual vibration signal e and the reference signal x, and drives the drive signal y. The signal y is output to the active engine mount 20.
[0052]
Specifically, the controller 25 uses the filter coefficient W _i (I = 0, 1, 2,..., I-1: I is the number of taps) A variable adaptive digital filter W is provided, and a predetermined sampling clock is supplied from the time when the latest reference signal x is input. At intervals, the filter coefficient W of the adaptive digital filter W _i Are sequentially output as the drive signal y, while the filter coefficient W of the adaptive digital filter W is based on the reference signal x and the residual vibration signal e. _i The process which updates suitably is performed.
[0053]
However, in this embodiment, the following equation (1) is used as an evaluation function in the SFX algorithm.
Jm = {e (n)} ² + Β {y (n)} ² ...... (1)
That is, in the LMS algorithm, the filter coefficient W in the direction in which the evaluation function Jm decreases. _i As is clear from the content of the right side of the above equation (1), the filter coefficient W is updated. _i Are successively updated so that the square value of the residual vibration signal e becomes smaller and the value obtained by multiplying the square value of the drive signal y by β becomes smaller. Β is a coefficient referred to as a divergence suppression coefficient, and the drive signal y tends to decrease as the divergence suppression coefficient β increases. That is, the divergence suppression coefficient β has an effect of suppressing divergence of control.
[0054]
The convergence coefficient is α, and the filter coefficient W is based on the evaluation function Jm expressed by the above equation (1). _i When the update formula is obtained, the following formula (2) is obtained.

Therefore, if “2α” in the equation (2) is a new convergence coefficient α and “2βα” is a new divergence suppression coefficient β, the filter coefficient W of the adaptive digital filter W is obtained. _i The update formula is as shown in the following formula (3).
[0055]

Here, the terms with (n) and (n + 1) represent values at sampling times n and n + 1. Also, the update reference signal R ^T Is theoretically a value obtained by filtering the reference signal x with a transfer function filter C ^ that models the transfer function C between the electromagnetic actuator 52 and the load sensor 64 of the active engine mount 20. Since the magnitude of the signal x is “1”, it coincides with the sum at the sampling time n of those impulse response waveforms when the impulse responses of the transfer function filter C ^ are successively generated in synchronization with the reference signal x.
[0056]
Theoretically, the reference signal x is filtered by the adaptive digital filter W to generate the drive signal y. Since the magnitude of the reference signal x is “1”, the filter coefficient W _i Are sequentially output as the drive signal y, the result is the same as when the filter processing result is the drive signal y.
[0057]
Then, the controller 25 outputs the drive signal y as described above and each filter coefficient W of the adaptive digital filter W. _i The update process is executed in synchronization with a fixed sampling clock that starts on the basis of the time when the latest impulse of the reference signal x is generated. Here, i (= 0, 1, 2,..., L−1) is a counter that is cleared in accordance with the generation of the impulse of the reference signal x and is incremented in synchronization with the fixed sampling clock. Filter coefficient W executed within (within sampling period) _j Update processing for each filter coefficient W _j If the counter used to execute is j (= 0, 1, 2,..., L−1), each filter coefficient W shown in the above equation (3) _j The updating formula is specifically as follows from the relationship between i and j.
[0058]

However, L is a filter coefficient W output as a drive signal y within one cycle (control cycle) of the reference signal x. _j And the period T of the reference signal x _x Is the fixed sampling clock period T _c The result of dividing by the number rounded up to the nearest decimal point. L1 is a filter coefficient W output as the drive signal y within one cycle of the reference signal x. _j , Which is an integer tap length determined in consideration of the decimal point of the actual tap length, and the period T of the reference signal x _x Is the fixed sampling clock period T _c The result of dividing by 1 is rounded off to the first decimal place.
[0059]
That is, in the controller 25, each time the counter j is incremented by 1 from 0 to (L−1), for each counter i that is incremented by 1 between 0 and (L−1), the above ( 4) Filter coefficient W according to the update formula of any one of (7) _j Will be updated.
[0060]
In order to execute the above equations (4) to (7), it is necessary to always know the number of taps L and the integer tap length L1 described above, and therefore the cycle T of the reference signal x. _x The latest value of is always detected. Specifically, the input interval between the latest impulse of the reference signal x and the immediately preceding impulse is constantly measured by a cycle measuring timer that counts clock pulses, and thereby the cycle T _x To get to.
[0061]
In addition to the period measurement timer, the controller 25 has a timer (sampling clock measurement timer) for recognizing that the sampling clock period has elapsed, and the impulse of the latest reference signal x. From the time when the signal is generated, the same time as the period of the sampling clock is repeatedly measured, and the drive signal y is output in synchronization with the sampling clock.
[0062]
Further, immediately after the ignition is turned on and the power is turned on, the controller 25 outputs the drive signal y as described above and each filter coefficient W of the adaptive digital filter W. _i Prior to the update process, a predetermined initialization process is executed. Examples of the initialization process include a memory check process of the microcomputer constituting the controller 25, a failure diagnosis process, an A / D converter check process, a RAM initialization process, a data read process from the EEPROM, and the like. For convenience of explanation, these processes will be referred to as initialization processes A, B, C, and D.
[0063]
That is, when the ignition is turned on and power is supplied, the controller 25 first executes initialization processes A, B, C, and D according to a determined procedure. These initialization processes A to D are divided into first half processes A, B and C and second half process D. Immediately after the ignition is turned on, the first half processes A, B and C are executed for the time being, and when it is completed, the process enters a standby state, and another calculation is performed until a new impulse of the reference signal x is input. Processing is not executed. When a new impulse of the reference signal x is input in this standby state, the above-described period measurement timer is cleared and the second half process D is started.
[0064]
When the second half processing D is completed, the process again enters a standby state until a new impulse of the reference signal x is input. When the input of the impulse is confirmed, the period measurement timer value at that time is held and the period measurement timer is used. Clear start timer again. Then, based on the held value, the period T of the reference signal x _x And the period T _x From the above, the tap number L and the integer tap length L1 are calculated.
[0065]
Note that the processing time required for each of the initialization processes A to D can be easily determined from the contents of the processes. Therefore, when the initialization processes A to D are divided into the first half process and the second half process, the processing time required for the second half process is the period T of the reference signal x immediately after the first half process is completed. _x The first half process and the second half process are selected so as to be shorter than the predicted shortest value. For example, when it is assumed that the engine 17 is started (ENG.ON) substantially at the same time as the ignition switch is turned on (IGN.ON), the engine speed at the completion time when the initialization processes A to D are all executed continuously. Is 200 rpm, the period of the reference signal x at that time (in the case of a reciprocating four-cylinder engine) is 0.15 seconds (150 msec). Therefore, with a margin, the latter half of the process is selected as the latter half of the process so that the processing time is 100 msec. In this case, if there is no initialization process that requires a processing time of approximately 100 msec, a plurality of initialization processes may be combined to form the latter half of the process so that the total processing time is about 100 msec.
[0066]
Further, as will be described later, a dead time T between the first half process and the second half process. _e Therefore, when all of the initialization processes A to D are continuously executed as described above, the period of the reference signal x at the time of completion, and the latter half when the initialization processes are divided into the first half process and the second half process. The period of the reference signal x when executing the process does not exactly match, and the latter is shorter under the same conditions. However, wasted time T _e In the present embodiment, as will be described later, since it does not become longer than one period of the reference signal x, the difference between the former and the latter is about the difference between adjacent periods of the reference signal x. This is extremely small. For this reason, if the latter half process is selected in view of the above-mentioned margin, it is possible to easily avoid that the processing time actually required for the latter half process exceeds the period of the reference signal x at that time. .
[0067]
Next, the operation of the present embodiment will be described.
When the ignition switch is turned on and power is supplied, the controller 25 can execute a predetermined calculation process, output a drive signal y to the electromagnetic actuator 52, and reduce vibration to the active engine mount 20. Active support force is generated. This will be specifically described with reference to FIG. 4 which is a flowchart showing an outline of processing executed in the controller 25.
[0068]
That is, when the power is supplied, the controller 25 starts the process shown in FIG. 4. First, in step 101, the initialization process A is executed as a subroutine process, and when this is completed, the process returns to the main routine shown in FIG. Then, the process proceeds to step 102, where the initialization process B as a subroutine process is executed. When this is completed, the process returns to the main routine of FIG. 4 and the process proceeds to step 103, where the initialization process C as a subroutine process is executed.
[0069]
On the other hand, if the driver further turns the engine key after the ignition switch is turned on, the engine 17 is started and the reference signal x is supplied to the controller 25. During this period, other interrupt processing is prohibited and the input of the reference signal x is not confirmed, so that the processing corresponding thereto is not executed.
[0070]
Then, when the processing of step 103 is completed, the controller 25 cancels the prohibition of interrupt, moves to step 104, and waits until a new impulse of the reference signal x is input.
[0071]
In other words, as shown in FIG. 5, when the ignition switch is turned on (IGN.ON), the initialization processes A, B, and C are executed continuously, and no other processes are executed during that time, but the initialization process C is completed. Time t ₁ The process is stopped until a new impulse of the reference signal x is input.
[0072]
Returning to FIG. 4, when the impulse of the reference signal x is confirmed in step 104, the routine proceeds to step 105, where the period measurement timer starts clearing, and then the routine proceeds to step 106, where the initialization process D as a subroutine process is performed. Is executed.
[0073]
That is, in the example of FIG. ₂ In step S1, the measurement of the timer for the first cycle calculation is started, and the initialization process D is started.
[0074]
At this time, the processing time required for the initialization process D is the period T of the reference signal x at that time. _x Therefore, when the initialization process D as a subroutine process is completed and the process returns to the main routine of FIG. 4, an impulse of a new reference signal x is generated after the determination of step 104 becomes “YES”. There is nothing like that. In the example of FIG. 5, the time t when the determination in step 104 is “YES”. ₂ At which the next impulse of the reference signal x is generated t _Three The initialization process D is surely completed up to the point.
[0075]
Therefore, the process proceeds from step 106 to step 107 in FIG. 4 and waits until a new impulse of the reference signal x is input. The value of the period measurement timer when the impulse input is confirmed in step 107 is the latest value. Period T of reference signal x _x It means that.
[0076]
Therefore, if the determination in step 107 is “YES”, the process proceeds to step 108 where the current value of the period measurement timer is stored, and then the process proceeds to step 109, where the period measurement timer is again cleared and started. To do.
[0077]
Then, the process proceeds to step 110, where the period T of the reference signal x is based on the value of the period measurement timer stored in step 108. _x Is obtained, and its period T _x And fixed sampling clock period T _c Based on the above, the tap number L and the integer tap length L1 are calculated. When the number of executions of step 110 is 2 or more after the process of FIG. 4 is started, the number of taps L is obtained based on the value of the counter i described later, and the value of the counter i and the sampling are obtained. It is also possible to obtain the integer tap length L1 based on the value of the clock measurement timer.
[0078]
Next, the process proceeds to step 111. After the counter i is cleared to zero, the process proceeds to step 112, the sampling clock measurement timer is cleared and started, and the process proceeds to step 113, where the i-th adaptive digital filter W Filter coefficient W _i Is output as the drive signal y.
[0079]
Next, the routine proceeds to step 114 where it is determined whether or not the counter i is 0. If this determination is “YES”, it is determined that the control cycle (the cycle of the reference signal x) has just started, In order to execute the initial process associated with the start of one control cycle, the routine proceeds to step 115, where the update reference signal R is based on the transfer function filter C ^. ^T Is calculated. In step 115, the update reference signal R for one new period of the reference signal x. ^T Are calculated together.
[0080]
When the determination at step 114 is “NO” and when the processing at step 115 is finished, the routine proceeds to step 116 where the residual vibration signal e is read. Then, the process proceeds to step 117, and the counter j is cleared to zero.
[0081]
Then, the process proceeds to step 118, where one of the above equations (4) to (7) is selected based on the counters i and j, and the filter coefficient W of the adaptive digital filter W corresponding to the counter j at that time. _j Is updated.
[0082]
Next, the process proceeds to step 119, where it is determined whether or not the next impulse of the reference signal x is input. If it is determined that the reference signal x is not input, the next of the adaptive digital filter W is determined. In order to execute the update of the filter coefficient or the output process of the drive signal y, the routine proceeds to step 120.
[0083]
In step 120, the total filter coefficient W _j Whether the counter j has reached the tap number L (more precisely, since the counter j starts from 0, the value obtained by subtracting 1 from the tap number L) is determined. If this determination is “NO”, the process proceeds to step 121, the counter j is incremented, and then the process returns to step 118 to repeatedly execute the above-described processing.
[0084]
However, if the determination in step 120 is “YES”, the filter coefficient W of the adaptive digital filter W _j Among them, since it can be determined that the update processing of the necessary number of filter coefficients as the drive signal y has been completed, the process proceeds to step 122 and the counter i is incremented. Next, the process proceeds to step 123 where the value of the sampling clock measurement timer cleared and started in step 112 is the fixed sampling clock cycle T. _c Then, the process returns to step 112 to repeat the above-described processing.
[0085]
On the other hand, if it is determined in step 119 that a new impulse of the reference signal x has been input, the process returns to step 108 and the above-described processing is repeatedly executed.
As a result of repeatedly executing the processing in FIG. 4 as described above, the controller 25 adapts to the electromagnetic actuator 52 of the active engine mount 20 in synchronization with the fixed sampling clock from the time when the reference signal x is input. Filter coefficient W of digital filter W _i Are sequentially supplied as the drive signal y.
[0086]
As a result, a magnetic force corresponding to the drive signal y is generated in the excitation coil 52b. However, since a constant magnetic force by the permanent magnet 52c has already been applied to the magnetic path forming member 78B, the magnetic force by the excitation coil 52b is permanent. It can be considered to act to increase or decrease the magnetic force of the magnet 52c. As described above, when the magnetic force of the permanent magnet 52c is increased or decreased, the movable member 78 is displaced in both forward and reverse directions, and when the movable member 78 is displaced, the volume of the main fluid chamber 84 is changed and supported by the change in volume. Since the expansion spring of the elastic body 32 is deformed, an active supporting force in both forward and reverse directions is generated in the active engine mount 20.
[0087]
Then, each filter coefficient W of the adaptive digital filter W that becomes the drive signal y _i Are sequentially updated according to the above equations (4) to (7) according to the SFX algorithm, and therefore each filter coefficient W of the adaptive digital filter W after a certain amount of time has passed. _i Is converged to the optimum value, the drive signal y is supplied to the active engine mount 20, so that the idling vibration and the booming noise vibration transmitted from the engine 17 to the vehicle body 18 side through the active engine mount 20 are generated. Will be reduced.
[0088]
Furthermore, in the present embodiment, as illustrated in FIG. 5, the initialization process immediately after the controller 25 is powered on is divided into the first half process A to C and the second half process D, and the second half process D is Since it is executed in parallel with the measurement processing by the first period measurement timer, the dead time T _e There is an advantage that can be greatly shortened.
[0089]
That is, in the conventional example shown in FIG. 6, the initialization processes A to D are continuously executed. _e Is at least the period T of the reference signal x _x Exceeding the maximum, period T _x However, in the present embodiment shown in FIG. 5, the dead time T _e Is at most the period T of the reference signal x _x Less than (when an impulse is input immediately before the completion of the initialization process C) and the timing is correct (when initialization is input immediately after the completion of the initialization process C), the dead time T _e Becomes almost zero. As a result, the time until the original vibration reduction control is executed can be shortened as compared with the conventional case, so that the vibration reduction effect can be exerted earlier.
[0090]
In addition, as a result of adjusting the resonance frequency of the fluid resonance system in the active engine mount 20 to 20 Hz, a certain amount of damping force is generated in the active engine mount 20 even when an engine shake that is a vibration of 5 to 15 Hz occurs. Therefore, the engine shake generated on the engine 17 side is attenuated to some extent by the active engine mount 20, and the engine shake is also attenuated by other fluid-filled engine mounts (not shown). The vibration level is reduced.
[0091]
Here, in the present embodiment, the engine 17 corresponds to the vibration source, the portion other than the load sensor 64 of the active engine mount 20 corresponds to the control vibration source, the load sensor 64 corresponds to the residual vibration detection means, The pulse signal generator 19 corresponds to the reference signal generation means, the controller 25 corresponds to the control means, steps 104, 105, 107, 110, and 119 in FIG. 4 and the period measurement timer in the controller 25 serve as the period acquisition means. Correspond.
[0092]
In the above embodiment, the residual vibration is detected by the load sensor 64 built in the active engine mount 20, but the present invention is not limited to this. For example, floor vibration is generated at the position of the passenger's foot in the passenger compartment. An acceleration sensor for detection may be provided, and the output signal of the acceleration sensor may be the residual vibration signal e.
[0093]
And in the said embodiment, although the case where the active noise vibration control apparatus for vehicles in this invention was applied to the active vibration control apparatus for vehicles which reduces the vibration transmitted to the vehicle body 18 from the engine 17 was demonstrated, The subject of the present invention is not limited to this, and may be an active noise control device for a vehicle that reduces noise transmitted from the engine 17 as a noise source to the vehicle interior. In the case of the control device, a loudspeaker as a control sound source for generating control sound in the vehicle interior and a microphone as residual noise detection means for detecting residual noise in the vehicle interior are provided, If the same arithmetic processing is executed, the same effect as that of the above embodiment can be obtained.
[0094]
Further, in each of the above embodiments, the SFX algorithm is applied as an algorithm for generating the drive signal y. However, the applicable algorithm is not limited to this, and for example, a normal LMS algorithm, Filtered-X An LMS algorithm or the like may be used.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a vehicle showing an embodiment.
FIG. 2 is a diagram showing an example of an active engine mount in a plan view.
3 is a cross-sectional view taken along arrows AA and BB in FIG. 2;
FIG. 4 is a flowchart showing an outline of vibration reduction processing.
FIG. 5 is a time chart for explaining the operation of the embodiment.
FIG. 6 is a time chart for explaining the operation of a conventional example.
[Explanation of symbols]
17 Engine (vibration source)
18 body
19 Pulse signal generator (reference signal generating means)
20 Active engine mount (control vibration source)
25 Controller (control means)
52 Electromagnetic actuator
64 Load sensor (residual vibration detection means)

Claims (3)

By reducing the noise or vibration emitted from the engine and the control sound or control vibration emitted from the control sound source or control vibration source, noise or vibration is reduced.
The period of the noise or vibration generated from the engine is acquired based on the input interval of the pulse signal synchronized with the rotation of the crankshaft of the engine, and the acquired pulse signal is generated based on the acquired period. In the active noise and vibration control device for a vehicle that is to be used for later arithmetic processing,
When the first half of the initialization process immediately after the power is turned on is completed, the initialization process enters a standby state, and when the input of the pulse signal is confirmed during the standby process, the period of the noise or vibration is acquired. Based on the measured value of the timer when the input of the new pulse signal is confirmed after the completion of the latter half of the process and the measurement by the timer for the first time and the latter half of the initialization process are started. the possible vehicular active noise and vibration control device according to claim the first round of the cycle of the noise or vibration is in so that the acquisition. Control sound source or control vibration source capable of generating control sound or control vibration that interferes with noise or vibration emitted from the engine, and residual noise that detects the noise or vibration after the interference and outputs it as a residual noise signal or residual vibration signal Based on detection means or residual vibration detection means, reference signal generation means for generating a reference signal composed of an impulse train synchronized with noise or vibration emitted from the engine, and based on the residual noise signal or residual vibration signal and the reference signal Control means for generating and outputting a drive signal for driving the control sound source or the control vibration source so that the noise or vibration after the interference is reduced, and
The control means includes period acquisition means for acquiring the period of the noise or vibration based on the latest impulse of the reference signal and the input interval of the immediately preceding impulse, and the noise acquired by the period acquisition means. Alternatively, in the vehicle active noise vibration control device adapted to use the period of vibration for the arithmetic processing after the latest impulse of the reference signal is generated,
The control means enters a standby state when the first half of the initialization process immediately after power is turned on, and when the input of a new impulse of the reference signal is confirmed during the standby, The measurement by the timer for obtaining the period of vibration and the latter half of the initialization process are started, and the input of a new impulse of the reference signal is confirmed after completion of the latter half of the process. An active noise / vibration control device for a vehicle , wherein a first cycle of the noise or vibration is acquired based on a measured value of a timer . Said initializing said processing time required for the second half of the process of treatment, the so processed the first half of the initializing process is shorter than the noise or vibration cycle immediately after completion of claim 1 which is selected the second half of the process or vehicular active noise and vibration control equipment according.

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