JP4101527B2 - Gear detector failure diagnosis device - Google Patents

Description

【００７０】
なおメータギヤ３２のギヤ比ＧＲ（ｍ）を
【００７１】
【数２】

【００７２】
とし、４速のギヤ比即ち減速比ＧＲ（４）を
【００７３】
【数３】

【００７４】
とする。（１）式の両辺に入力主ギヤ１１の歯数ＺＭ５を乗じると、車速センサ２１の回転軸３１が１回転する間即ち車速センサ２１が２５パルス発生する間に、変速機回転センサ２０から発生する変速機パルス数ＰＴＭが算出できる（入力主ギヤ１１の通過歯数＝入力副ギヤ１２の通過歯数なので）。即ち、
【００７５】
【数４】

【００７６】
基本的にはこの（２）式に従えば上記原理に基づくギヤ段検出方法を実現できる。即ち、（２）式における各ギヤ段のギヤ比ＧＲ（１），ＧＲ（２），ＧＲ（３），・・・と、メータギヤ３２のギヤ比ＧＲ（ｍ）と、入力主ギヤ１１の歯数ＺＭ５とを予めＥＣＵ１６に記憶しておき、ＥＣＵ１６において、車速センサ２１からの２５個のパルスをカウントすると共に、その間に変速機回転センサから発生された変速機パルス数ＰＴＭをカウントする。そしてこのカウントされた変速機パルス数ＰＴＭと、上記メータギヤのギヤ比ＧＲ（ｍ）及び入力主ギヤ１１の歯数ＺＭ５とを（２）式に代入し、その上で（２）式に各ギヤ段のギヤ比ＧＲ（１），ＧＲ（２），ＧＲ（３），・・・を順次代入していく。そして（２）式がほぼ成立したギヤ段を現在のギヤ段として決定する。以上を第一の方法とする。
【００７７】
しかしながら、本実施形態ではＥＣＵ１６における内部処理を簡単化するため、以下のような処理を行っている。（２）式の両辺をギヤ比ＧＲ（４）で割ると、
【００７８】
【数５】

【００７９】
となる。つまり、変速機パルス数ＰＴＭをギヤ比で割った値はギヤ段に拘わらず一定値Ｎｄとなるのである。そこで、ＥＣＵ１６にはこの一定値Ｎｄと、各ギヤ段のギヤ比ＧＲ（１），ＧＲ（２），ＧＲ（３），・・・のみを予め記憶しておく。そしてギヤ段の検出に際しては、ＥＣＵ１６において、車速センサ２１からの２５個のパルスをカウントする間の変速機回転センサ２０からの変速機パルス数ＰＴＭをカウントし、このカウントされた変速機パルス数ＰＴＭと上記一定値Ｎｄとを（３）式に代入し、その上で（３）式に各ギヤ段のギヤ比ＧＲ（１），ＧＲ（２），ＧＲ（３），・・・を順次代入していき、（３）式がほぼ成立したギヤ段を現在のギヤ段として決定する。これを第二の方法とする。
【００８０】
なお、実測値としての変速機パルス数ＰＴＭを現在のギヤ段のギヤ比で割っても理論上の一定値Ｎｄには正確に一致しないことがある。よってその除算によって得られた値が一定値Ｎｄに略一致したとき、例えば一定値Ｎｄに対しその数％以内に入っているとき（３）式成立とする。これが「ほぼ成立」の意味である。
【００８１】
また、（３）式に基づく別の方法としては、カウントされた変速機パルス数ＰＴＭを一定値Ｎｄで割ってギヤ比を算出し、このギヤ比に対応したギヤ段を現在のギヤ段として決定してもよい。この計算でも前記同様に除算によって得られた値が現在のギヤ段のギヤ比に正確に一致しないことがあるので、そのギヤ比に略一致、例えばそのギヤ比に対し数％以内に入っているとき、そのギヤ比に対応したギヤ段を現在のギヤ段としてもよい。これを第三の方法とする。
【００８２】
ここで、上記第二の方法を具体値を挙げて説明する。図１２に示すように、例えばメータドライブギヤ３３の歯数Ｚｄ１＝４、メータドリブンギヤ３４の歯数Ｚｄ２＝１０、入力主ギヤ１１の歯数ＺＭ５＝２８とする。このとき（３）式の左辺＝１０／４×２８＝７０となる。そこでこの７０という値を一定値ＮｄとしてＥＣＵ１６に記憶しておく。
【００８３】
また、図１３（ａ）に示すような各ギヤ段のギヤ比ＧＲをＥＣＵ１６に記憶しておく。なおここでは便宜上５速の変速機の例を取り扱う。図１に示した変速機は基本となる５速変速機に６速部分（６速主ギヤＭ６等からなる）をエキストラギヤとして追加したものであり、この６速部分を省略すれば５速変速機となる。
【００８４】
図１３（ｂ）に示すのは、実際に変速機が各々のギヤ段に入っているとき、車速パルスが２５個発生したならば発生するであろう変速機パルス数ＰＴＭである。従っていま仮に車速パルスが２５個発生する間に実際の変速機パルスが２０３個発生し、これがＥＣＵ１６でカウントされたとする。するとＥＣＵ１６は、２０３を各ギヤ段のギヤ比ＧＲ（Ｒ）＝５．０６８，ＧＲ（１）＝５．３１５，ＧＲ（２）＝２．９０８・・・で割った値を順次算出し、先の一定値Ｎｄ＝７０に最も近いものを探し出す。ここでは２速のときが２０３／２．９０８＝６９．８と７０に最も近い（つまり７０の数％以内に入っている）ため、現在のギヤ段を２速と判定する。
【００８５】
図１３（ａ）の（Ｎｄ）は、各ギヤ段の変速機パルス数ＰＴＭを各ギヤ段のギヤ比ＧＲで割って小数点以下を切り捨てた値を参考までに示したものである。先の２速の例でいえば、６９．８の小数点以下を切り捨てた６９．０が（Ｎｄ）の値である。
【００８６】
なお、第三の方法に従えば、実際の変速機パルス数ＰＴＭ＝２０３を一定値Ｎｄ＝７０で割って得られる値２．９に最も近いギヤ比を探し出し、ＧＲ（２）＝２．９０８が最も近いので、２速と判定することになる。
【００８７】
さて、図１４に示すように、車種によっては車速センサ２１とＥＣＵ１６との間にパルス整合器３５が介在され、ＥＣＵ１６がパルス整合器３５を介して車速パルスを入力する場合がある。即ち、タイヤ動半径やファイナルギヤ比等のバリエーションが比較的多い車型については、工場出荷時のメータドリブンギヤ３４の組み替えが大変なことがあるので、この組み替えを行わない代わりにパルス整合器３５を調整し、これにより車速パルスの時間間隔を調整し、ＥＣＵ１６には車速６０ｋｍ／ｈのとき６３７ｒｐｍに相当する車速パルスが入力されるようにすることがある。
【００８８】
この場合、メータギヤ比はほぼ６０ｋｍ／ｈ＝６３７ｒｐｍ相当となるようなギヤ比に固定されると共に、パルス整合器３５にはその調整時に補正係数αが設定される。補正係数αは通常０．８〜１．２の範囲で可変であるが、パルス整合器３５が調整された後は一定値に固定される。パルス整合器３５への１の入力に対しその出力はαとなり、入力が２５パルスだとするとその出力は２５αパルスとなる。設定後のαの値はＥＣＵ１６に送られて記憶される。
【００８９】
この場合（２）式は以下のように変形できる。
【００９０】
【数６】

【００９１】
従って、両辺をギヤ比ＧＲ（４）で割った値も一定値となり、この一定値をＮｄとすると（３）式は以下のように改められる。
【００９２】
【数７】

【００９３】
従って、前記同様、（２）’式を用いて第一の方法によりギヤ段を決定でき、（３）’式を用いて第二及び第三の方法によりギヤ段を決定できる。
【００９４】
図１５にはこの場合の車速と変速機回転速度との関係を示している。補正係数αのとり得る範囲（αｍｉｎ＝０．８〜αｍａｘ＝１．２）に対応して、各ギヤ段における比例直線にもハッチングで示すようなある程度の範囲が生じる。ここで仮に図示の如く各ギヤ段の範囲が重ならないようであれば、計算値がいずれかの範囲に入ったときその入ったギヤ段を現在のギヤ段として特定することが可能である。
【００９５】
即ち、（３）’式によれば、補正係数αが最小値αｍｉｎのときＮｄは最大値Ｎｄｍａｘとなり、補正係数αが最大値αｍａｘのときＮｄは最小値Ｎｄｍｉｎとなる。そこで、実際にカウントされた変速機パルス数ＰＴＭをギヤ比ＧＲで割った値ＰＴＭ／ＧＲを各ギヤ段毎に計算し、Ｎｄｍｉｎ≦ＰＴＭ／ＧＲ≦Ｎｄｍａｘを満たすようなギヤ段を現在のギヤ段として決定することができる。
【００９６】
このように、かかるギヤ段検出装置によれば、センサの出力を時間要素で割って速度換算した値を用いるのではなく、センサから出力されるパルスの数自体（所謂パルスの生値）を用いて現在のギヤ段を決定するので、低車速時にも正確なギヤ段検出を行え、検出精度を上げることができ、ギヤ段の誤判定を未然に防止できる。
【００９７】
特にかかるギヤ段検出装置により、ギヤポジションセンサ２４の故障時にもギヤ段を検出でき、クラッチ制御（特に低車速時のクラッチ制御）が支障無く行える。また図１７に示すように４速又は６速のいずれに入っているかが１個のセレクトスイッチＳＷ２では判別できない場合であっても、このセレクトスイッチＳＷ２との併用により、或いはかかるギヤ段検出装置単独により、４速又は６速のいずれに入っているかを判別できる。そしてより積極的にはセンサやスイッチの数をさらに減少し、或いは全て省略することも可能であり、これにより一層のコスト低減が可能となる。
【００９８】
なお、低車速時には一定数のパルスが溜まるまでに時間がかかるので、ギヤ段検出に従来より時間が掛かるかもしれないが、それでも従来より遙かに正確なギヤ段検出が可能なのでそのメリットは大である。一方高車速時にはパルスが一瞬で溜まるのでギヤ段検出も即行える。
【００９９】
さて、次に、本発明に関わるギヤ段検出器の故障診断装置を説明する。
【０１００】
上記で説明したように、本実施形態ではギヤ段検出装置によっても現在或いは実際のギヤ段を検出できる。よってギヤポジションセンサ２４により検出されたギヤ段（以下「センサ検出ギヤ段」という）と、ギヤ段検出装置により検出されたギヤ段（以下「パルス検出ギヤ段」という）とが異なる場合、ギヤポジションセンサ２４とギヤ段検出装置とのいずれかが故障（又は異常、以下同様）であると考えることができる。
【０１０１】
ギヤ段検出装置の故障は以下のようにしてＥＣＵ１６により検出される。例えば図１２及び図１３に示した上記第二の方法による例において、装置が正常ならば、実際に計測された変速機パルス数ＰＴＭを各ギヤ段のギヤ比ＧＲで割った値はほぼ一定値Ｎｄ＝７０となるはずである。しかしそれが７０±Ｘ（ｅｘ．Ｘ＝３）の範囲に入らないようであれば装置を故障と判定することができる。例えば変速機が実際に２速に入っていた場合、図１３（ｂ）によれば約２０３の変速機パルスが発生するはずであるが、これが例えば２２０とかいうように大きく２０３から外れるような変速機パルス数が検知された場合、装置を故障と判断することになる。なおノイズ等の影響で一時的に計算結果が予定値から大きく外れることもある。このような場合も含め、計算結果が予定値から大きく外れたときはギヤ段を検出しない。
【０１０２】
一方、ギヤ段検出装置により正確なパルス検出ギヤ段が検出されたという前提の下で、ＥＣＵ１６は、センサ検出ギヤ段がパルス検出ギヤ段と異なるとき、ギヤポジションセンサ２４が故障であると判断する。図１７に示したように、ギヤポジションセンサ２４はシフトストロークセンサ３１とセレクトスイッチＳＷ１、ＳＷ２とからなり、ギヤポジションセンサ２４の故障とはこれらセンサ又はスイッチのいずれかの故障を意味する。
【０１０３】
最も簡単な故障検出方法としては以下の方法がある。仮にシフトストロークセンサ３１が正常でシフト方向最前列の位置（リバース、２速、４速又は６速相当の位置）を示している場合、ギヤ段検出装置では４速と判断しているのに、セレクトスイッチＳＷ１、ＳＷ２は両方ＯＦＦで２速を検出していたとする。この場合、本来セレクトスイッチＳＷ２はＯＮでなければならないのだから、セレクトスイッチＳＷ２が故障、特に断線等によるオープン故障であると判断することができる。
【０１０４】
しかし、本実施形態ではさらに正確な故障判断を行うため以下の方法を採用している。なお前提としてシフトストロークセンサ３１とギヤ段検出装置とは正常であるとする。図１８▲１▼に示されるように、いま仮に変速機が実際にリバースに入っており、真のギヤ段がリバースであったとする。そしてシフトストロークセンサ３１によってシフト方向最前列の位置（リバース、２速、４速又は６速相当の位置）が示されており、他方セレクトスイッチＳＷ１のオープン故障によりセレクトスイッチＳＷ１、ＳＷ２がＯＦＦになっていて、ギヤポジションセンサ２４によっては誤って２速が検出されているとする。この場合、車速パルス２５個当たりの変速機パルス数ＰＴＭは図１３（ｂ）にも示したように約３５４個が実測されるはずである。この３５４個を誤検出された２速のギヤ比＝２．９０８で割ると１２１．７となり約１２１となる。
【０１０５】
従って、本実施形態では、図１８に示されるマップのうち変速機パルス数ＰＴＭを除く各データをＥＣＵ１６に予め記憶しておき、セレクトスイッチＳＷ１又はＳＷ２のオープン故障を正確に検知するようになっている。即ち、実測された変速機パルス数ＰＴＭ（上記リバースの例▲１▼でいえば３５４個、以下同様）を、ギヤポジションセンサ２４によって誤検出されたギヤ段（２ｎｄ）のギヤ比（２．９０８）で割り、その値が対応する一定値Ｎｄ（１２１．０）にほぼ一致したら、セレクトスイッチＳＷ１がオープン故障であると判断し、真のギヤ段を対応するギヤ段（リバース）とする。逆にほぼ一致しなかったらオープン故障の判断はしない。ギヤ段検出装置の故障や一時的なノイズの影響等が考えられるからである。
【０１０６】
図１８▲２▼は、真のギヤ段が１速でシフトストロークセンサ３１が最後列の位置（１速、３速又は５速相当の位置）を示しているのに、セレクトスイッチＳＷ１のオープン故障により誤って３速が検出されている場合である。
【０１０７】
図１８▲３▼は、真のギヤ段が４速でシフトストロークセンサ３１が最前列の位置を示しているのに、セレクトスイッチＳＷ２のオープン故障により誤って２速が検出されている場合である。
【０１０８】
図１８▲４▼は、真のギヤ段が５速でシフトストロークセンサ３１が最後列の位置を示しているのに、セレクトスイッチＳＷ２のオープン故障により誤って３速が検出されている場合である。
【０１０９】
このように、故障時のデータを予め記憶しておいてこれと照合し確認する作業を加えることによって、ギヤ段検出器の故障診断をより正確に行える。なおここではセレクトスイッチＳＷ１又はＳＷ２のオープン故障のみを示したが、ショート等のクローズ故障やシフトストロークセンサ３１の故障にも同様の方法が採用できる。
【０１１０】
さて、このようにギヤポジションセンサ２４の故障が検出されると、ＥＣＵ１６はこの故障が検出されている時間を計測する。より具体的には、ＥＣＵ１６は、所定時間（例えば２０ｍｓｅｃ）毎に故障が検出されたかどうかの判断と、故障が検出された場合の内蔵カウンタの単位数（例えば１）ずつの増大とを繰り返す。なおカウント値の初期値はゼロである。そしてそのカウント値が所定値（例えば１０又は１４）に達したら、最終的にギヤポジションセンサ２４の故障と判断する。
【０１１１】
一方、そのカウンタ増大中に現ギヤ段からのギヤ抜き操作があったとき、ＥＣＵ１６は、そのギヤ段に再度入れられるまでギヤ抜き操作時のカウント値を保持する。例えば、現ギヤ段＝４速での走行中にギヤポジションセンサ２４の故障が検知され、カウントアップが実行されているときに、４速からのギヤ抜き操作が行われた事実がノブスイッチ２５の出力により検知されると、カウントアップを中断すると共にギヤ抜き操作時のカウント値を保持する。そして再び４速に入れられ且つ故障が検知されれば、保持されていたカウント値からカウントアップを再開し、カウント値が所定値に達したら最終的にギヤポジションセンサ２４の故障と判断する。
【０１１２】
逆に、カウントアップ中にギヤポジションセンサ２４からの正常な信号、即ち４速であることを示す信号を検出したときは所定時間毎にカウンタを１ずつ減少する。なおカウント値をキャンセルし初期値に戻すようにしてもよい。
【０１１３】
また、故障を検出しているカウントアップ中には、予めどのスイッチがどんな故障（断線又は短絡）をしているかという故障モードが分かっているので、断線故障と検出しているスイッチがＯＮになった場合や、短絡故障と検出しているスイッチがＯＦＦになった場合等の正常な信号を検出したときに、速やかに所定時間毎にカウントを１ずつ減少させたり、カウント値をキャンセルし初期値に戻すようにしてもよい。これにより、正確且つ迅速に故障診断できるようになる。
【０１１４】
従来は、故障が検知されてもカウントアップ中にギヤ抜き操作があったときは、カウント値をキャンセルするような方法が採られていた。しかし、本実施形態では、ギヤ抜き操作があったときカウント値を保持し、再度そのギヤ段に入れられたとき故障が検出されればカウントアップを再開するので、ギヤ抜き操作により故障の疑いが解消されることはなく、正確な故障診断が行える。これにより信頼性を高めることが可能となる。
【０１１５】
なお、本発明の実施形態は上述のものに限られない。例えば、上記実施形態ではカウンタを用いてギヤ段検出器の故障検出時間を計測したが、例えばタイマ等を用いて故障検出時間を直接計測するようにしても良い。
【０１１６】
また、上記実施形態では自動クラッチとマニュアル変速機とを組合せた動力伝達装置であったが、クラッチはマニュアルでも構わないし、変速機も自動であっても構わない。要は、変速機のギヤ段検出器を備えるあらゆる装置に本発明を適用できる。また車両の動力伝達装置以外にも適用できるものである。
【０１１７】
上記実施形態ではギヤ段検出装置によるギヤ段検出に際し、車速パルスの単位数を１回転（３６０°位相）相当の２５パルスに設定したが、これは例えば２回転（７２０°位相）相当、半回転（１８０°位相）相当のように適宜変更できるものである。これを一般的にＮ回転相当とすると、式（１）〜（３）、（２）’、（３）’の両辺にＮを掛けるのと同じこととなり、実質的には上記方法が変更されるわけではなく、カウントされる変速機パルス数の値（図１３（ｂ）、図１８）が変わるだけである。
【０１１８】
上記実施形態のギヤ段検出装置では、変速機の出力軸側パルス（車速パルス）を基準とし、出力軸側パルスが単位数（２５パルス）をカウントしたときの入力軸側パルス数によりギヤ段を特定したが、これは逆でも良く、入力軸側パルス（変速機パルス）を基準としてもよい。
【０１１９】
上記実施形態では入力軸側パルス発生手段を副軸側に設けた変速機回転センサ２０とし、入力副ギヤ１２の通過歯数をカウントしているが、これは入力軸側に設けたセンサで構成しても良く、入力主ギヤ１１の通過歯数をカウントするようにしてもよい。
【０１２０】
【発明の効果】
以上説明したように本発明によれば、ギヤ段検出器の故障診断を正確に行え、信頼性を高められるという、優れた効果が発揮される。
【図面の簡単な説明】
【図１】本実施形態に係る車両の動力伝達装置を示すスケルトン図である。
【図２】本実施形態に係る油圧供給装置を示す油圧回路図である。
【図３】本実施形態に係る油圧供給装置の特性線図である。
【図４】本実施形態に係る電子制御装置を示す構成図である。
【図５】本実施形態に係るクラッチ接続制御の内容を示すタイムチャートで、シフトアップの場合である。
【図６】本実施形態に係るクラッチ接続制御の内容を示すタイムチャートで、シフトダウンの場合である。
【図７】本実施形態に係るクラッチ接続制御の内容を示すタイムチャートで、ガレージシフトの場合である。
【図８】本実施形態に係るシフトアップ時のステップデューティ算出マップである。
【図９】本実施形態に係るシフトダウン時のステップデューティ算出マップである。
【図１０】本実施形態に係るガレージシフト時のステップデューティ算出マップである。
【図１１】ギヤ段検出装置の一実施形態を示す構成図である。
【図１２】図１１のギヤ段検出装置を簡略化して示した図である。
【図１３】ギヤ段検出に用いる各ギヤ段のギヤ比等の具体値を示す。
【図１４】ギヤ段検出装置の他の実施形態を示す構成図である。
【図１５】補正係数の範囲を考慮した車速と変速機回転速度との関係を示すグラフである。
【図１６】一般的な車速と変速機回転速度との関係を示すグラフである。
【図１７】本実施形態に係るギヤポジションセンサの構成を示す図である。
【図１８】ギヤ段検出器の故障判定に用いるマップである。
【符号の説明】
８ インプットシャフト
９ アウトプットシャフト
１６ 電子コントロールユニット（ＥＣＵ）
２０ 変速機回転センサ
２１ 車速センサ
２４ ギヤポジションセンサ
３１ シフトストロークセンサ
ＧＲ ギヤ段のギヤ比
Ｎｄ 一定値
ＰＴＭ 車速パルス数
ＳＷ１，ＳＷ２ セレクトスイッチ
Ｔ／Ｍ 変速機[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gear stage detector failure diagnosis apparatus, and more particularly to an apparatus for diagnosing whether or not a gear stage detector that detects a gear stage of a vehicle transmission is faulty.
[0002]
[Prior art]
The present inventors have provided a fluid coupling (including a torque converter) that can be locked up between an engine and a transmission and a friction type transmission clutch in series, and the power of the vehicle that automatically connects and disconnects the transmission clutch during a shift. A new transmission device was developed. In this case, at the time of shifting, the clutch is automatically disengaged simultaneously with the start of gear removal, and the clutch is automatically engaged simultaneously with gear-in.
[0003]
Thus, since the clutch is controlled according to the gear position of the transmission, it is important to detect the current or actual gear position of the transmission. Therefore, a gear stage detector including a sensor and a switch is provided in the transmission. However, if the gear stage detector breaks down due to disconnection or short circuit, there is a problem such that clutch control becomes impossible, so normally the gear stage is detected by another means for fail-safe. . If the gear detected by the gear detector is different from the gear detected by another means, it is considered that the gear detector has failed and the clutch is detected by the gear detected by another means. Execute control.
[0004]
[Problems to be solved by the invention]
However, when diagnosing a failure of a conventional gear stage detector, even if a failure is detected in a state of being in a predetermined gear stage, the fault data is temporarily canceled if the gear is removed from the gear stage. In many cases, there is a problem that accurate failure determination cannot be performed.
[0005]
In view of the above problems, the present invention has been invented, and an object thereof is to provide a failure diagnosis apparatus that can accurately determine a failure of a gear stage detector.
[0006]
[Means for Solving the Problems]
A failure detection apparatus for a gear detector according to the present invention includes a gear detector including a sensor, a switch, and the like for detecting that the transmission has entered a predetermined gear, A failure detection means for detecting a failure of the gear detector, and a failure determination for measuring the time during which the failure is detected and finally determining that the gear detector is failed when the time reaches a predetermined time And a holding means for holding a time value at the time of the gear release operation when the gear release operation from the gear stage is performed during the time measurement.
[0007]
Here, it is preferable that the failure determination means restarts the time measurement from the held time value when a failure is detected by the failure detection means even after re-entering the gear stage.
[0008]
Further, it is preferable that the failure determination means decreases the time or sets an initial value when no failure is detected by the failure detection means.
[0009]
Further, the failure detection means uses an output pulse of a sensor provided on the input / output shaft side of the transmission, and sets the gear stage based on the number of other pulses when one reference pulse is output as a unit number. When the gear stage detecting means to detect and the detected gear stage is different from the gear stage detected by the gear stage detector, if the gear stage detector is broken, it is detected by this. The wrong gear stage will be determined, and the number of pulses of the other will be divided by the gear ratio of the wrong gear stage, and when the value almost matches the predetermined value, the gear stage will be finally detected. It is preferable that it comprises a judging means for judging that the device is out of order.
[0010]
In addition, as a substitute value for the time, a count value of a counter that can be increased or decreased by a unit number every predetermined time may be used.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the accompanying drawings.
[0012]
FIG. 1 shows a power transmission device for a vehicle to which the present invention is applied. As shown in the figure, a clutch mechanism 1 is provided between the engine E and the transmission T / M. The clutch mechanism 1 includes a fluid coupling (fluid coupling) 2 provided on the upstream side in the power transmission direction, and a downstream side thereof. In this embodiment, the clutch is a friction type clutch provided in series, and in this embodiment, the transmission clutch 3 is a wet multi-plate clutch. The fluid coupling here is a broad concept including a torque converter, and the torque converter is also used in the present embodiment. The vehicle to which this apparatus is applied is a relatively large vehicle such as a truck. Engine E is a diesel engine.
[0013]
The fluid coupling 2 is interposed between the pump 4 connected to the output shaft (crankshaft) of the engine, the turbine 5 facing the pump 4 and connected to the input side of the clutch 3, and the turbine 5 and the pump 4. The stator 6 is provided. A lock-up clutch 7 is provided in parallel with the fluid coupling 2, which connects and disconnects the pump 4 and the turbine 5 to enable the fluid coupling 2 to be locked up. The transmission clutch 3 has an input side connected to the turbine 5 via the input shaft 3a, an output side connected to the input shaft 8 of the transmission T / M, and connects / disconnects between the fluid coupling 2 and the transmission T / M. .
[0014]
The transmission T / M includes an input shaft (input shaft) 8, an output shaft (output shaft) 9 disposed coaxially with the input shaft 8, and a counter shaft (secondary shaft) 10 disposed in parallel therewith. An input main gear 11 is provided on the input shaft 8. The output shaft 9 is supported by a first speed main gear M1, a second speed main gear M2, a third speed main gear M3, a fourth speed main gear M4, and a reverse main gear MR. A main gear M6 is fixed. The counter shaft 10 has an input sub gear 12 meshed with the input main gear 11, a first speed sub gear C1 meshed with the first speed main gear M1, a second speed sub gear C2 meshed with the second speed main gear M2, and 3 A third speed sub gear C3 meshing with the speed main gear M3, a fourth speed sub gear C4 meshing with the fourth speed main gear M4, and a reverse sub gear CR meshing with the reverse main gear MR via the idle gear IR are fixed. In addition, a sixth-speed sub gear C6 that meshes with the sixth-speed main gear M6 is pivotally supported.
[0015]
According to this transmission T / M, when the sleeve S / R1 spline-engaged with the hub H / R1 fixed to the output shaft 9 is spline-engaged with the dog DR of the reverse main gear MR, the output shaft 9 is reversely rotated. When the sleeve S / R1 is spline-engaged with the dog D1 of the first-speed main gear M1, the output shaft 9 rotates at the first speed. Then, when the sleeve S / 23 spline-engaged with the hub H / 23 fixed to the output shaft 9 is spline-engaged with the dog D2 of the second-speed main gear M2, the output shaft 9 rotates at the second speed, and the sleeve When S / 23 is spline-engaged with the dog D3 of the third speed main gear M3, the output shaft 9 rotates at the third speed.
[0016]
When the sleeve S / 45 that is spline-engaged with the hub H / 45 fixed to the output shaft 9 is spline-engaged with the dog D4 of the 4-speed main gear M4, the output shaft 9 rotates at a speed equivalent to 4th speed, and the sleeve When S / 45 is spline-engaged with the dog D5 of the input main gear 11, the output shaft 9 rotates at the fifth speed (direct connection). When the sleeve S6 splined to the hub H6 fixed to the countershaft 10 is splined to the dog D6 of the sixth speed sub gear C6, the output shaft 9 rotates at the sixth speed. Each of the sleeves is manually operated by a driver by a shift lever in the cab through a shift fork and a shift rod (not shown). That is, the transmission T / M is a manual type.
[0017]
The transmission clutch 3 has a normal wet multi-plate clutch configuration. That is, although not shown in the drawings, in the clutch casing filled with oil, the clutch plates are alternately meshed with each other on the input side and the output side, and the clutch plates are pressed against each other by the clutch piston or released. Then, the clutch is connected and disconnected. Referring to FIG. 2, the clutch piston 27 is always biased to the disengagement side by the clutch spring 28, and the clutch 3 is engaged when a hydraulic pressure exceeding this is applied to the clutch piston 27. The clutch fastening force or the torque capacity of the clutch is increased according to the applied hydraulic pressure.
[0018]
Next, a hydraulic pressure supply device for supplying the operating hydraulic pressure to the transmission clutch 3 will be described. As shown in FIG. 2, the oil in the oil tank 13 is sucked and discharged by the hydraulic pump OP through the filter 14, and the discharge pressure is adjusted by the relief valve 15 to create a constant line pressure PL. The oil of the line pressure PL is sent to the clutch 3 under pressure control or pressure reduction control. For this reason, two valves, a clutch control valve CCV and a clutch solenoid valve CSV, are used. That is, a pilot operated hydraulic control system is employed in which the clutch control valve CCV connected to the main hydraulic line is opened and closed according to the pilot hydraulic pressure Pp sent from the clutch solenoid valve CSV. The magnitude of the pilot oil pressure Pp is changed according to a duty pulse output from an electronic control unit (hereinafter referred to as ECU) 16.
[0019]
That is, the clutch solenoid valve CSV is an electromagnetic valve having an electromagnetic solenoid. The clutch solenoid valve CSV is opened / closed according to ON / OFF of a duty pulse signal output from the ECU 16, and the line pressure PL is always supplied. Then, the pilot oil pressure Pp corresponding to the duty (duty ratio) D of the duty pulse is output.
[0020]
The clutch control valve CCV is a spool valve that is controlled steplessly based on the pilot oil pressure Pp and is not electronically controlled. That is, the built-in spool is stroked to the open side according to the magnitude of the pilot oil pressure Pp, thereby adjusting the line pressure PL as appropriate and feeding it to the clutch 3 as the clutch pressure Pc. Thus, as a result, the hydraulic pressure supplied to the clutch 3 is duty-controlled by the ECU 16.
[0021]
An accumulator 17 is provided in the middle of the path connecting the clutch solenoid valve CSV and the clutch control valve CCV.
[0022]
FIG. 3 shows a characteristic diagram of the hydraulic pressure supply device. The horizontal axis represents the duty D of the duty pulse output from the ECU 16, more specifically, the ON duty indicating the ratio of the solenoid ON time in the basic control cycle (20 msec in this embodiment). In this embodiment, the clutch is completely engaged when the duty D is 0 (). This is to make it possible to maintain the running of the vehicle by setting the clutch in the connected state even when no power is supplied to the clutch solenoid valve CSV due to an electrical system failure or the like (so-called OFF stack state). .
[0023]
As shown in the figure, the larger the duty D is, the smaller the contact is, and the smaller the duty is. As the value of the duty D decreases, the value of the pilot hydraulic pressure Pp output from the clutch control valve CCV increases proportionally, and accordingly, the hydraulic pressure supplied to the clutch, that is, the clutch pressure Pc, and the torque capacity of the clutch 3 Tc tends to increase proportionally. Although the valve opening V of the clutch control valve CCV is 3 positions in the figure, the spool valve is slightly stroked at an intermediate opening (valve opening 0 mm in the figure) other than fully open and fully closed in practice. The pressure Pc can be changed continuously.
[0024]
Although there is a control system for the lock-up clutch 7 in this embodiment, the description is omitted here because it is not directly related to the present invention. The configuration of the hydraulic control system is substantially the same as that of the transmission clutch 3.
[0025]
Next, an electronic control device for electronically controlling the power transmission device will be described with reference to FIG. In addition to the clutch solenoid valve CSV, various switches and sensors are connected to the ECU 16 in order to electronically control the apparatus. This includes an engine rotation sensor 18 for detecting the engine rotation speed (specifically, the rotation speed, the same applies hereinafter), and a turbine rotation sensor 19 for detecting the rotation speed on the input side of the clutch 3, that is, the rotation speed of the turbine 5. A transmission rotation sensor 20 for detecting the rotation speed of the transmission T / M, typically the rotation speed of the input auxiliary gear 12, and a vehicle speed sensor 21 for detecting the vehicle speed are included. These sensors are also shown in FIG. In particular, the ECU 16 calculates the rotational speed of the input shaft 8 from the output of the transmission rotation sensor 20 and the gear ratio of the input main gear 11 and the input sub-gear 12, and uses this to calculate the output side rotational speed of the clutch 3 and the transmission T. / M input shaft side rotation speed.
[0026]
The ECU 16 also detects a parking brake switch 22 for detecting whether the parking brake is operating, a foot brake switch 23 for detecting whether the foot brake is operating, and a gear position of the transmission. A gear position sensor 24 is also connected. In particular, the gear position sensor 24 forms a gear stage detector according to the present invention.
[0027]
A knob switch 25 is also connected to the ECU 16. That is, in this embodiment, in order to detect the start timing of the shifting operation by the driver or to determine the timing to start the clutch disengagement, the shift knob of the cab can slightly swing in the shift direction with respect to the lever. The knob switch 25 is provided between the lever and the shift knob. When the shift operation is performed by the driver, if the shift knob is swung prior to the operation of the lever, the knob switch 25 is turned ON, and the clutch disengagement is started with this as a signal. The specific configuration is the same as that shown in JP-A-11-236931.
[0028]
Further, the power transmission device of the present embodiment is provided with a slope start assist device (HSA; Hill Start Aid) as shown in the same publication, and in the cab to manually turn on / off the device. An HSA switch 26 is provided, and the HSA switch 26 is connected to the ECU 16.
[0029]
Next, the operation and control method of the power transmission device according to this embodiment will be described.
[0030]
In this power transmission device, the power of the engine E is transmitted in the order of the fluid coupling 2, the transmission clutch 3, and the transmission T / M. In principle, the lock-up clutch 7 is always turned on (contacted) after starting, and turned off (disconnected) when stopping and starting. Therefore, when starting, the creep of the fluid coupling 2 can be used like an AT car, and the control becomes simpler than that in which the friction clutch is electronically controlled to start. Can prevent loss. The transmission clutch 3 is automatically connected / disconnected every time a shift is made. This is the same as a normal MT car.
[0031]
Here, the connection / disconnection control of the lock-up clutch 7 will be described in detail. The lock-up clutch 7 is engaged at a predetermined speed (approximately 10 km / h in the present embodiment) which is a relatively low vehicle speed. More precisely, the lock-up clutch engagement is established when the input shaft rotation speed reaches a predetermined rotation speed (uniformly 900 rpm in the present embodiment) or more at each gear stage. When the vehicle starts at the starting stage (for example, the second speed, which is a frequently used starting stage) and the input shaft speed reaches the predetermined speed (900 rpm), the lockup clutch is engaged, and the vehicle speed at this time is low ( About 10km / h).
[0032]
First, the operation at the start of the vehicle, that is, the case of a garage shift will be described. Suppose that the driver tries to start and operates the shift lever to the starting stage while the vehicle is stopped in the gear neutral and brake (including both foot brake and parking brake) operating states. Then, in the shift lever, the knob knob 25 is turned on before the operation of the lever, so that the knob switch 25 is turned on, and the clutch 3 is automatically disconnected by this signal. Then, when the shift lever is continuously operated, the transmission T / M is geared into the starting stage, and when this is detected by the gear position sensor 24, the clutch 3 is automatically connected. Since the turbine 5 is stopped from the drive wheel side by this connection, the pump 4 slides with respect to the turbine 5 and a creep force is generated. Therefore, if the brake is released or the accelerator is depressed, the vehicle starts to move.
[0033]
Next, the operation at the time of shifting while the vehicle is running, that is, the case of shifting up or down will be described. When the vehicle is traveling at a predetermined gear stage, it is assumed that the driver tries to shift gear and operates the shift lever to the next gear stage. Then, prior to the operation of the lever, the shift knob swings, the knob switch 25 is turned on, and the clutch 3 is automatically disconnected with this signal. When the shift lever is subsequently operated, the transmission T / M is geared into the next shift stage. When this is detected by the gear position sensor 24, the clutch 3 is automatically connected. This completes the shift. During this shift, the lockup clutch 7 remains ON, and the engine power is transmitted to the clutch 3 as it is.
[0034]
The clutch control method during traveling will be described in detail with reference to FIGS. FIG. 5 shows the case of shifting up, and FIG. 6 shows the case of shifting down. First, the case of upshifting will be described.
[0035]
As shown in FIG. 5, when the knob switch is turned on (t1), the clutch is completely disengaged, and when the shift gear is operated to shift to the next gear stage, the clutch connection is started (t2).
[0036]
First, one-shot contact control is executed. That is, the start duty (one-shot contact duty) Dst at which the clutch 3 is greatly engaged to the fully connected position beyond the torque point is output from the ECU 16 during the waiting time Δtst that is a short time. Here, the start duty Dst = 0 (%) and the waiting time Δtst = 0.1 sec.
[0037]
In the conventional one-shot contact control, the start duty Dst = about 60 (%) and the waiting time Δtst = 0.5 sec. The reason why the start duty Dst is set to about 60 (%) is that a torque point duty, which will be described later, is about 50%, and the clutch needs to be surely stopped before the torque point, and the waiting time Δtst is set to 0.5 sec. This is because this time is required to finish the initial invalid stroke of the clutch and the clutch pressure increase at the start duty = about 60%.
[0038]
On the other hand, in the one-shot contact control here, the start duty on the contact side than the conventional one is output for a shorter time than the conventional one. In this way, since the duty value is the contact side, the amount of oil applied to the clutch is increased, and the clutch can be operated to the connection side faster. On the other hand, since the clutch itself needs to be stopped before the torque point as in the prior art, such a waiting time Δtst is set by an actual machine test. As a result, the same one-shot contact mode as in the prior art can be realized in a shorter time than in the prior art, and the clutch engagement time can be further shortened while preventing clutch contact shock.
[0039]
In particular, as in the present embodiment, it is preferable to set the start duty Dst to the closest value (completely connected equivalent value) = 0 (%). This is because the highest clutch engagement speed can be obtained. Similarly, a value in the vicinity thereof (for example, 10 (%)) is also preferable. However, the value of the start duty Dst can be arbitrarily selected as long as it is a value closer to the conventional side. The value of the start duty Dst may be determined from a map or the like based on the vehicle operating state. Since the waiting time Δtst is also set according to the model, it is not limited to 0.1 sec. This value can also take an arbitrary value.
[0040]
The one-shot contact control is open loop control. The torque point of the clutch is a learning value and is stored in the ECU 16 with the duty value. For example, as shown in FIG. 3, the torque point learning value is a duty D = 50 () indicating a torque capacity Tcm = about 200 (Nm). If the torque capacity diagram shifts as shown by a broken line due to variations in the clutch or the like, the torque point learning value also changes accordingly.
[0041]
Now, after the clutch one-shot engagement control, the control shifts to clutch loose engagement control (t3). That is, the slow engagement duty Dk that causes the clutch 3 to be loosely engaged is output from the ECU 16 at predetermined time intervals. The predetermined time here is equal to the control cycle Δt = 20 msec in this embodiment. However, it may be equal to a plurality of control cycles nΔt. Hereinafter, this predetermined time is referred to as a slow contact cycle.
[0042]
In this gradual engagement control, the value of the gradual engagement duty for each gradual engagement cycle is determined based on the rotational difference on the input / output side of the clutch. The value Ne of the engine speed detected by the engine speed sensor 18 is used as the clutch input side speed. This is because the lock-up clutch is engaged during traveling, and it can be considered that the clutch input side rotational speed = engine rotational speed. As the clutch output side rotational speed, the value Ni of the input shaft rotational speed calculated from the output of the transmission rotation sensor 20 and the gear ratio as described above is used.
[0043]
Since the shift is up here, the engine speed Ne is higher than the input shaft speed Ni as shown in FIG. Therefore, the rotation difference ΔN is calculated by subtracting the input shaft rotation speed Ni from the engine rotation speed Ne (ΔN = Ne−Ni).
[0044]
As shown in FIG. 8, the value of the step duty Ds with respect to the rotation difference ΔN is set in a map format for each gear stage of the transmission. This step duty calculation map is stored in advance in the ECU 16.
[0045]
Specific contents of the clutch loose engagement control are as follows. First, the slow contact duty Dk3 as an initial value is output in the slow contact cycle at time t3. The value of the slow contact duty Dk3 is slightly closer to the torque point learning value. Then, the rotation difference ΔN3 at this time is calculated, and the step duty Ds3 is determined from the current gear and the value of ΔN3 according to the map of FIG. In the slow contact cycle at time t4, which is the next control round, a value obtained by subtracting the step duty Ds3 from the previous slow contact duty Dk3 is set as the current slow contact duty Dk4, which is output from the ECU 16. Hereinafter, similarly, the rotation difference ΔNn is calculated at the slow contact period at time tn (n = 4, 5, 6,...), The step duty Dsn is determined according to the map of FIG. In the slow contact cycle of tn + 1, the step duty Dsn is subtracted from the previous slow contact duty Dkn to obtain the current slow contact duty Dkn + 1, which is output from the ECU 16. By repeating such control, the clutch is gradually connected, and the rotational difference ΔN gradually decreases.
[0046]
Note that the calculation cycle of the step duty Ds and the control cycle Δt are not necessarily equal. At this time, the slow contact duty Dk is updated every time the step duty Ds is calculated, and this update cycle becomes the slow contact cycle.
[0047]
In this way, when the predetermined slow contact end condition is satisfied, the slow contact control is terminated, and the clutch rapid contact control is shifted to. The slow engagement end condition of the present embodiment is that the rotation difference ΔN is a small value of 150 rpm or less, or that the duty output from the ECU 16 reaches the slow engagement end duty De that can be considered that the clutch is sufficiently connected. is there. In the clutch quick contact control, a quick contact duty = 0 is output for a predetermined time = 0.3 sec. Thereafter, clutch complete engagement control is performed, and clutch engagement control is terminated. Similarly, in the clutch complete contact control, the complete contact duty = 0 is output for a predetermined time = 1 sec.
[0048]
Next, the case of downshift will be described with reference to FIGS. When shifting down, it is almost the same as when shifting up. The difference is that when the gear is downshifted, as shown in FIG. 6 (d), the input shaft rotational speed Ni is higher than the engine rotational speed Ne, so the calculation of the rotational difference ΔN is also reversed, and the rotational difference ΔN is This is a point calculated by subtracting the engine speed Ne from the speed Ni (ΔN = Ni−Ne). Further, the value of the step duty Ds is set separately from the case of upshifting, and specifically, a step duty calculation map for downshifting as shown in FIG. 9 is prepared separately. In this map, the values in the map are more suitable for downshifting. The contents of the other clutch contact control are the same as described above, and in the one-shot contact control, the start duty Dst = 0 (%) is output as a waiting time Δtst = 0.1 sec.
[0049]
Next, the case of the garage shift will be described with reference to FIGS. In FIG. 7, before time t1, the vehicle is stopped before starting, and the gear neutral, brake operating state, engine idling, transmission clutch 3 is connected, lockup clutch 7 is disconnected, engine output is fluid coupling 2, transmission clutch 3 to the countershaft 10 of the transmission T / M and the main gear M1. This is because the mission oil stored in the transmission T / M is agitated by the rotation of the sub-gears 12. At this time, the engine speed Ne, the turbine speed Nt, and the input shaft speed Ni are all equal.
[0050]
When the driver performs a gear shifting operation from this state, the knob switch is first turned ON and the clutch is completely disengaged (t1). As a result, the input shaft rotational speed Ni falls, and when the gear is engaged in the starting stage, the clutch is engaged. Is started (t2). Simultaneously with the gear-in, the input shaft 8 is stopped by a brake from the drive wheel side, so that the rotation speed becomes zero.
[0051]
The first one-contact control is the same as described above. That is, the start duty Dst = 0 (%) is output at a constant waiting time Δtst = 0.1 sec. Next, the slow contact control similar to the above is executed. In the loose contact control, the step duty Ds is read from the garage shift dedicated map shown in FIG. In this loose connection control, the turbine 5 is gradually braked from the drive wheel side in accordance with the clutch connection, so the turbine rotational speed Nt gradually decreases.
[0052]
Therefore, when the rotational difference ΔNet (= Ne−Nt) between the engine rotational speed Ne and the turbine rotational speed Nt reaches a predetermined value Nm (300 rpm in the present embodiment), it is considered that the clutch is substantially substantially connected, and is slow. The contact control is terminated, and thereafter, the clutch sudden contact control and the clutch complete contact control similar to those described above are performed, and the connection control is terminated.
[0053]
Next, a failure diagnosis device for a gear stage detector according to the present invention applied to such a power transmission device for a vehicle will be described.
[0054]
In the power transmission device, the clutch engagement is started simultaneously with the gear-in, and the shift-up / shift-down determination is performed, so that the current or actual gear stage or gear position of the transmission is always detected. In principle, this detection is performed by the gear position sensor 24 (see FIG. 4) as a gear position detector.
[0055]
FIG. 17 shows details of the gear position sensor 24. The gear position sensor 24 is provided in the transmission mechanism of the transmission. R, 1, 2,... Mean reverse, 1st speed, 2nd speed,..., And the shift lever is moved along an H pattern as shown. The gear position sensor 24 includes a shift stroke sensor 31 that detects a stroke in the shift direction of a member interlocked with the shift lever, and two select switches SW1 and SW2 that detect a position in the select direction of the member. One select switch SW1 is provided at a select position corresponding to reverse and first gear, and is turned ON at that position. The other select switch SW2 is provided at the select position corresponding to the 4th speed and the 5th speed, and is turned ON at that position. For example, when the shift stroke sensor 31 indicates the position in the forefront row in the shift direction (reverse, second speed, fourth speed, or sixth speed position), if the select switch SW1 is ON and the select switch SW2 is OFF, the reverse, select switch SW1 If SW2 is OFF, the current gear stage can be determined such as the second speed. Whether it is 4th speed or 6th speed cannot be determined by the select switch SW2, so it is determined by a gear position detecting device described later. In addition to the above, various types of gear stage detectors are possible.
[0056]
By the way, when a failure such as a disconnection or a short circuit occurs in the gear position sensor 24, it becomes impossible to determine which position the gear is currently in, which causes troubles in clutch control and the like. Therefore, as a backup, in this embodiment, a device for indirectly detecting or estimating the gear stage of the transmission is provided without using the gear position sensor 24. This will be described in detail below.
[0057]
Such a gear position detection device discriminates the current gear position by using rotation pulses respectively generated from the vehicle speed sensor 21 and the transmission rotation sensor 22 during the rotation operation of the transmission. The configuration is shown in FIG. 11, and the same elements as those described above are denoted by the same reference numerals.
[0058]
As shown in the figure, the present apparatus is mainly composed of the transmission T / M, a vehicle speed sensor 21, a transmission rotation sensor 22, and an ECU 16. The rotation shaft 31 of the vehicle speed sensor 21 is rotationally driven by the output shaft 9 via the meter gear 32. Although the meter gear 32 is simplified in FIG. 1, the meter drive gear 33 fixed to the output shaft 9 as shown in FIG. 11 and the meter driven gear 34 meshed with the meter gear 32 and fixed to the rotary shaft 31 are shown in detail. It consists of. The vehicle speed sensor 21 generates a pulse signal at every equal phase interval of the rotating shaft 31 and generates a predetermined number (25 in this embodiment) of pulse signals per rotation of the rotating shaft 31. This pulse signal is directly input to the ECU 16. Since the rotating shaft 31 is interlocked with the output shaft 9, the vehicle speed sensor 21 eventually constitutes output shaft side pulse generating means for generating a number of pulse signals corresponding to the rotational phase of the output shaft (output shaft) 9.
[0059]
On the other hand, the transmission rotation sensor 22 generates a pulse signal each time the teeth of the input sub-gear 12 facing it pass, and outputs this pulse signal to the ECU 16. Since the input sub-gear 12 is interlocked with the input shaft 8, the transmission rotation sensor 22 eventually constitutes input shaft side pulse generating means for generating a number of pulse signals corresponding to the rotational phase of the input shaft (input shaft) 8. .
[0060]
By the way, as shown in FIG. 16, when the transmission is in any gear stage, theoretically, the relationship between the vehicle speed and the transmission rotational speed (that is, the input shaft rotational speed) depends on the gear ratio of each gear stage. It becomes proportional relation. In the graph, only the first speed (1st), the second speed (2nd), and the third speed (3rd) are illustrated. Therefore, if the transmission rotational speed at a certain vehicle speed is known, it is possible to determine what speed the current gear stage is. This principle is used in the prior art disclosed in JP-A-4-171353.
[0061]
However, in reality, there is no problem because the difference ΔN in transmission speed between the gears is large at a relatively high vehicle speed V2, but the difference ΔN is small at a relatively low vehicle speed V1. There is a possibility that an error between the calculated value and the calculated value becomes large and erroneous determination of the gear stage occurs.
[0062]
That is, in the ECU, the number of pulses (referred to as vehicle speed pulse and transmission pulse, respectively) generated from the vehicle speed sensor and the transmission rotation sensor during a predetermined time determined in advance is counted. A process of calculating the vehicle speed and the transmission rotational speed by dividing by the predetermined time is executed. However, since the pulse generation interval is long at low vehicle speeds, there is no guarantee that a sufficient number of pulses are included in the predetermined time, so the calculated value obtained by dividing this by the time element is not necessarily accurate. It cannot be said that it is a bad value. Therefore, the method for determining the gear position based on such a calculated value is likely to cause an erroneous determination. If the influence of noise or the like is taken into consideration, there is a greater possibility that the calculated value will deviate from an accurate value and cause erroneous determination.
[0063]
Therefore, in this apparatus, instead of using the calculated value divided by such a time element, the gear stage determination is performed using the pulse itself output from the sensor.
[0064]
The principle of the gear position detection method in this apparatus is as follows. That is, if the transmission is in one of the gear stages, the input shaft rotates in a certain phase while the output shaft rotates in a certain phase. Then, how much the input shaft rotates with respect to a certain output shaft rotation phase is determined according to the gear ratio of the gear stage that is entered at that time.
[0065]
Therefore, it is possible to specify the current gear stage by detecting how many input shaft side rotation pulses are generated while a certain number of output shaft side rotation pulses are generated. To explain with an easy-to-understand example, for example, when the vehicle speed sensor 21 generates 10 pulses, which is the unit number, the transmission rotation sensor 22 is 50 for the first speed, 40 for the second speed, and for the third speed. Assume that 30 pulses are generated. The values of the first speed of 50, the second speed of 40, and the third speed of 30 are stored in the ECU 16 in advance, and the vehicle speed sensor 21 receives 10 pulses when the transmission is actually rotating while the vehicle is running. The number of pulses of the transmission rotation sensor 22 is counted while If the counted number of pulses is 50, the current gear can be determined such that the first speed is 40, the second speed is 40, the third speed is 30, and so on. The device is in principle like this.
[0066]
Although this example is based on the output shaft side, it can also be based on the input shaft side.
[0067]
The embodiment shown in FIG. 11 follows this principle. The code | symbol which attaches Z first in the figure represents the number of teeth of each gear. The vehicle speed sensor 21 generates 25 vehicle speed pulses (25 pls) per one rotation (1 rev) of the rotating shaft 31. The vehicle speed pulse input to the ECU 16 is required to be equivalent to 637 rpm when the vehicle speed is 60 km / h, and the gear ratio of the meter gear 32 is set so that such a vehicle speed pulse is generated from the vehicle speed sensor 21. Specifically, the number of teeth Zd1 of the meter drive gear 33 and the number of teeth Zd2 of the meter driven gear 34 are determined. Note that if the tire moving radius, final gear ratio, and the like differ depending on the vehicle type, the meter driven gear 34 is appropriately reassembled.
[0068]
Here, a case where the transmission is in the fourth speed will be described as an example. The input shaft rotational speed Ni when the rotating shaft 31 of the vehicle speed sensor 21 makes one rotation is obtained by the following equation (1).
[0069]
[Expression 1]

[0070]
Note that the gear ratio GR (m) of the meter gear 32 is
[0071]
[Expression 2]

[0072]
4th gear ratio, that is, reduction ratio GR (4)
[0073]
[Equation 3]

[0074]
And When both sides of the equation (1) are multiplied by the number of teeth ZM5 of the input main gear 11, generated from the transmission rotation sensor 20 while the rotation shaft 31 of the vehicle speed sensor 21 rotates once, that is, while the vehicle speed sensor 21 generates 25 pulses. The transmission pulse number PTM to be calculated can be calculated (since the number of passing teeth of the input main gear 11 = the number of passing teeth of the input sub gear 12). That is,
[0075]
[Expression 4]

[0076]
Basically, according to the equation (2), a gear position detection method based on the above principle can be realized. That is, the gear ratios GR (1), GR (2), GR (3),..., The gear ratio GR (m) of the meter gear 32 and the teeth of the input main gear 11 in the equation (2). The number ZM5 is stored in the ECU 16 in advance, and the ECU 16 counts 25 pulses from the vehicle speed sensor 21 and counts the number of transmission pulses PTM generated from the transmission rotation sensor during that time. The counted transmission pulse number PTM, the gear ratio GR (m) of the meter gear and the number of teeth ZM5 of the input main gear 11 are substituted into the equation (2), and then each gear is converted into the equation (2). The gear ratios GR (1), GR (2), GR (3),... Are sequentially substituted. Then, the gear stage in which the expression (2) is substantially established is determined as the current gear stage. The above is the first method.
[0077]
However, in the present embodiment, the following processing is performed in order to simplify the internal processing in the ECU 16. Dividing both sides of equation (2) by gear ratio GR (4)
[0078]
[Equation 5]

[0079]
It becomes. That is, the value obtained by dividing the transmission pulse number PTM by the gear ratio becomes a constant value Nd regardless of the gear stage. Therefore, the ECU 16 stores only the constant value Nd and the gear ratios GR (1), GR (2), GR (3),. When the gear stage is detected, the ECU 16 counts the transmission pulse number PTM from the transmission rotation sensor 20 while counting 25 pulses from the vehicle speed sensor 21, and the counted transmission pulse number PTM. And the above-mentioned constant value Nd are substituted into the equation (3), and then the gear ratios GR (1), GR (2), GR (3),... Are sequentially substituted into the equation (3). Then, the gear stage in which the expression (3) is substantially established is determined as the current gear stage. This is the second method.
[0080]
Note that even if the transmission pulse number PTM as an actual measurement value is divided by the gear ratio of the current gear stage, it may not exactly match the theoretical constant value Nd. Therefore, when the value obtained by the division substantially coincides with the constant value Nd, for example, when the value is within a few percent of the constant value Nd, the expression (3) is established. This is the meaning of “almost established”.
[0081]
As another method based on the equation (3), the gear ratio is calculated by dividing the counted transmission pulse number PTM by the constant value Nd, and the gear stage corresponding to this gear ratio is determined as the current gear stage. May be. In this calculation as well, the value obtained by division may not exactly match the gear ratio of the current gear stage, as described above. Sometimes, the gear stage corresponding to the gear ratio may be the current gear stage. This is the third method.
[0082]
Here, the second method will be described with specific values. As shown in FIG. 12, for example, the number of teeth Zd1 = 4 of the meter drive gear 33, the number of teeth Zd2 = 10 of the meter driven gear 34, and the number of teeth ZM5 = 28 of the input main gear 11 are set. At this time, the left side of equation (3) = 10/4 × 28 = 70. Therefore, this value 70 is stored in the ECU 16 as a constant value Nd.
[0083]
Further, the gear ratio GR of each gear stage as shown in FIG. Here, for the sake of convenience, an example of a 5-speed transmission will be treated. The transmission shown in FIG. 1 is obtained by adding a 6-speed portion (consisting of a 6-speed main gear M6, etc.) as an extra gear to the basic 5-speed transmission, and if this 6-speed portion is omitted, a 5-speed transmission is achieved. It becomes a machine.
[0084]
FIG. 13B shows the number of transmission pulses PTM that will be generated if 25 vehicle speed pulses are generated when the transmission is actually in each gear stage. Accordingly, it is assumed that 203 actual transmission pulses are generated while 25 vehicle speed pulses are generated, and this is counted by the ECU 16. Then, the ECU 16 sequentially calculates a value obtained by dividing 203 by the gear ratio GR (R) = 5.068, GR (1) = 5.315, GR (2) = 2.908. Find the one closest to the previous constant value Nd = 70. Here, since the second speed is 203 / 2.908 = 69.8, which is closest to 70 (that is, within a few percent of 70), the current gear stage is determined to be the second speed.
[0085]
(Nd) in FIG. 13A shows, for reference, a value obtained by dividing the transmission pulse number PTM of each gear stage by the gear ratio GR of each gear stage and rounding down the decimal point. In the example of the second speed, 69.0 obtained by rounding down the decimal point of 69.8 is the value of (Nd).
[0086]
According to the third method, the gear ratio closest to the value 2.9 obtained by dividing the actual transmission pulse number PTM = 203 by the constant value Nd = 70 is found, and GR (2) = 2.908. Is the closest, so it is determined to be the second speed.
[0087]
As shown in FIG. 14, depending on the vehicle type, a pulse matching unit 35 may be interposed between the vehicle speed sensor 21 and the ECU 16, and the ECU 16 may input a vehicle speed pulse via the pulse matching unit 35. In other words, for vehicle types with relatively large variations in tire dynamic radius, final gear ratio, etc., it may be difficult to reassemble the meter-driven gear 34 at the time of shipment from the factory, so adjust the pulse matching unit 35 instead of not performing this reconfiguration. Thus, the time interval of the vehicle speed pulse is adjusted, and the vehicle speed pulse corresponding to 637 rpm may be input to the ECU 16 when the vehicle speed is 60 km / h.
[0088]
In this case, the meter gear ratio is fixed to a gear ratio corresponding to approximately 60 km / h = 637 rpm, and a correction coefficient α is set in the pulse matching unit 35 during the adjustment. The correction coefficient α is normally variable in the range of 0.8 to 1.2, but is fixed to a constant value after the pulse matching unit 35 is adjusted. For one input to the pulse matcher 35, the output is α, and if the input is 25 pulses, the output is 25α pulses. The value of α after setting is sent to the ECU 16 and stored therein.
[0089]
In this case, equation (2) can be modified as follows.
[0090]
[Formula 6]

[0091]
Accordingly, a value obtained by dividing both sides by the gear ratio GR (4) is also a constant value, and when this constant value is Nd, the expression (3) is amended as follows.
[0092]
[Expression 7]

[0093]
Accordingly, as described above, the gear stage can be determined by the first method using the expression (2) ′, and the gear stage can be determined by the second and third methods using the expression (3) ′.
[0094]
FIG. 15 shows the relationship between the vehicle speed and the transmission rotational speed in this case. Corresponding to the possible range of the correction coefficient α (αmin = 0.8 to αmax = 1.2), a certain range as shown by hatching occurs in the proportional straight line at each gear stage. Here, if the ranges of the gear stages do not overlap as shown in the figure, when the calculated value falls within any range, it is possible to specify that gear stage as the current gear stage.
[0095]
That is, according to the equation (3) ′, Nd is the maximum value Ndmax when the correction coefficient α is the minimum value αmin, and Nd is the minimum value Ndmin when the correction coefficient α is the maximum value αmax. Therefore, a value PTM / GR obtained by dividing the actually counted transmission pulse number PTM by the gear ratio GR is calculated for each gear stage, and the gear stage satisfying Ndmin ≦ PTM / GR ≦ Ndmax is determined. Can be determined as
[0096]
In this way, according to the gear position detection device, the number of pulses output from the sensor itself (so-called pulse raw value) is used instead of using the value obtained by dividing the output of the sensor by the time element and converting the speed. Since the current gear stage is determined, accurate gear stage detection can be performed even at low vehicle speeds, detection accuracy can be improved, and erroneous determination of the gear stage can be prevented.
[0097]
In particular, such a gear position detection device can detect the gear position even when the gear position sensor 24 fails, and can perform clutch control (particularly, clutch control at low vehicle speeds) without any trouble. Further, as shown in FIG. 17, even if one select switch SW2 cannot determine whether the vehicle is in 4th speed or 6th speed, it can be used in combination with this select switch SW2 or the gear position detecting device alone. Thus, it is possible to determine whether the vehicle is in 4th speed or 6th speed. More actively, the number of sensors and switches can be further reduced, or all of them can be omitted, thereby further reducing the cost.
[0098]
In addition, it takes time for a certain number of pulses to accumulate at low vehicle speeds, so it may take more time than before to detect the gear position, but it is still much more advantageous because it can detect gear stages much more accurately than before. It is. On the other hand, at high vehicle speeds, pulses accumulate instantly so that gear position can be detected immediately.
[0099]
Next, the gear stage detector failure diagnosis apparatus according to the present invention will be described.
[0100]
As described above, in the present embodiment, the current or actual gear can be detected also by the gear detection device. Therefore, when the gear stage detected by the gear position sensor 24 (hereinafter referred to as “sensor detection gear stage”) and the gear stage detected by the gear stage detection device (hereinafter referred to as “pulse detection gear stage”) are different, It can be considered that either the sensor 24 or the gear position detection device is faulty (or abnormal, the same applies hereinafter).
[0101]
The failure of the gear stage detection device is detected by the ECU 16 as follows. For example, in the example of the second method shown in FIGS. 12 and 13, if the apparatus is normal, the value obtained by dividing the actually measured transmission pulse number PTM by the gear ratio GR of each gear stage is substantially constant. Nd = 70 should be obtained. However, if it does not fall within the range of 70 ± X (ex. X = 3), the device can be determined as a failure. For example, when the transmission is actually in the second speed, according to FIG. 13 (b), about 203 transmission pulses should be generated. If the number of pulses is detected, the device is determined to be faulty. Note that the calculation result may be significantly different from the expected value temporarily due to the influence of noise or the like. Including such cases, the gear stage is not detected when the calculation result deviates significantly from the planned value.
[0102]
On the other hand, on the assumption that an accurate pulse detection gear stage is detected by the gear stage detection device, the ECU 16 determines that the gear position sensor 24 is faulty when the sensor detection gear stage is different from the pulse detection gear stage. . As shown in FIG. 17, the gear position sensor 24 includes a shift stroke sensor 31 and select switches SW1 and SW2, and the failure of the gear position sensor 24 means a failure of any of these sensors or switches.
[0103]
The simplest failure detection method includes the following methods. If the shift stroke sensor 31 is normal and indicates the position in the forefront row in the shift direction (reverse, 2nd, 4th or 6th speed), the gear position detection device determines that it is 4th. Assume that the selector switches SW1 and SW2 are both OFF and the second speed is detected. In this case, since the select switch SW2 must originally be ON, it can be determined that the select switch SW2 is in failure, particularly an open failure due to disconnection or the like.
[0104]
However, in the present embodiment, the following method is adopted to make a more accurate failure determination. It is assumed that the shift stroke sensor 31 and the gear position detection device are normal. As shown in FIG. 18 (1), it is assumed that the transmission is actually in reverse and the true gear is reverse. The shift stroke sensor 31 indicates the position in the foremost line in the shift direction (reverse, second speed, fourth speed, or sixth speed position). On the other hand, the select switches SW1 and SW2 are turned OFF due to an open failure of the select switch SW1. In addition, it is assumed that the second speed is erroneously detected by the gear position sensor 24. In this case, about 354 transmission pulse numbers PTM per 25 vehicle speed pulses should be actually measured as shown in FIG. Dividing these 354 pieces by the erroneously detected second gear ratio = 2.908 gives 121.7, which is approximately 121.
[0105]
Therefore, in this embodiment, each data excluding the transmission pulse number PTM in the map shown in FIG. 18 is stored in the ECU 16 in advance, and an open failure of the select switch SW1 or SW2 is accurately detected. Yes. That is, the actually measured transmission pulse number PTM (354 in the case of the reverse example {circle over (1)}, the same applies hereinafter) of the gear ratio (2.908) erroneously detected by the gear position sensor 24 (2.908). ) And the value almost coincides with the corresponding constant value Nd (121.0), it is determined that the select switch SW1 has an open failure, and the true gear is set as the corresponding gear (reverse). On the other hand, if they do not match, open failure is not judged. This is because a failure of the gear stage detection device, a temporary noise influence, or the like can be considered.
[0106]
18 (2) shows that the true gear stage is 1st and the shift stroke sensor 31 indicates the position of the last row (position corresponding to 1st speed, 3rd speed or 5th speed), but the select switch SW1 has an open failure. This is a case where the third speed is detected by mistake.
[0107]
FIG. 18 (3) shows the case where the true gear stage is 4th and the shift stroke sensor 31 indicates the position of the front row, but the 2nd gear is erroneously detected due to the open failure of the select switch SW2. .
[0108]
FIG. 18 (4) shows a case where the third gear is erroneously detected due to an open failure of the select switch SW2 even though the true gear stage is fifth and the shift stroke sensor 31 indicates the position of the last row. .
[0109]
As described above, the failure diagnosis of the gear detector can be performed more accurately by storing the data at the time of failure in advance and adding the work of checking and checking the data. Although only an open failure of the select switch SW1 or SW2 is shown here, the same method can be adopted for a close failure such as a short circuit or a failure of the shift stroke sensor 31.
[0110]
When the failure of the gear position sensor 24 is detected in this way, the ECU 16 measures the time during which this failure is detected. More specifically, the ECU 16 repeats the determination of whether or not a failure is detected every predetermined time (for example, 20 msec) and the increment of the number of units of the built-in counter (for example, 1) when the failure is detected. Note that the initial value of the count value is zero. When the count value reaches a predetermined value (for example, 10 or 14), it is finally determined that the gear position sensor 24 is out of order.
[0111]
On the other hand, when there is a gear release operation from the current gear stage while the counter is increasing, the ECU 16 holds the count value at the time of the gear release operation until the gear is re-entered. For example, the fact that the gear position sensor 24 has failed during the traveling at the current gear stage = 4th speed and the count-up is being executed is the fact that the gear release operation from the 4th speed has been performed. When detected by the output, the count-up is interrupted and the count value at the time of gear release operation is held. If the fourth speed is entered again and a failure is detected, the count-up is restarted from the held count value. When the count value reaches a predetermined value, it is finally determined that the gear position sensor 24 has failed.
[0112]
On the contrary, when a normal signal from the gear position sensor 24, that is, a signal indicating the fourth speed is detected during counting up, the counter is decremented by 1 every predetermined time. The count value may be canceled and returned to the initial value.
[0113]
Further, during the count-up a failure is detected in advance so which switch is found failure modes or have any failure (broken wire or a short circuit), the switch detects the disconnection failure is ON When a normal signal is detected, such as when a switch that detects a short-circuit failure is turned off, the count is quickly decremented by 1 every predetermined time, or the count value is canceled and the initial value You may make it return to. As a result, the failure diagnosis can be performed accurately and quickly.
[0114]
Conventionally, even if a failure is detected, a method has been adopted in which the count value is canceled when a gear release operation is performed during count-up. However, in this embodiment, the count value is held when the gear is removed, and when the failure is detected when the gear is re-entered, the count-up is restarted. It is not solved and accurate fault diagnosis can be performed. This makes it possible to improve reliability.
[0115]
The embodiment of the present invention is not limited to the above. For example, in the above embodiment, the failure detection time of the gear stage detector is measured using a counter, but the failure detection time may be directly measured using a timer or the like, for example.
[0116]
In the above embodiment, the power transmission device is a combination of an automatic clutch and a manual transmission. However, the clutch may be a manual, and the transmission may be automatic. In short, the present invention can be applied to any device having a gear stage detector of a transmission. Further, the present invention can be applied to devices other than vehicle power transmission devices.
[0117]
In the above embodiment, when detecting the gear stage by the gear stage detection device, the unit number of the vehicle speed pulse is set to 25 pulses corresponding to one rotation (360 ° phase), but this is equivalent to, for example, two rotations (720 ° phase) and half rotation It can be changed as appropriate, such as (180 ° phase). If this is generally equivalent to N rotations, it is the same as multiplying both sides of equations (1) to (3), (2) ′, and (3) ′ by N, and the method is substantially changed. Instead, the value of the number of transmission pulses to be counted (FIG. 13 (b), FIG. 18) only changes.
[0118]
In the gear stage detection device of the above embodiment, the gear stage is determined by the number of pulses on the input shaft side when the output shaft side pulse counts the number of units (25 pulses) on the basis of the output shaft side pulse (vehicle speed pulse) of the transmission. Although specified, this may be reversed, and an input shaft side pulse (transmission pulse) may be used as a reference.
[0119]
In the above embodiment, the input shaft side pulse generating means is the transmission rotation sensor 20 provided on the auxiliary shaft side, and the number of passing teeth of the input auxiliary gear 12 is counted, but this is constituted by a sensor provided on the input shaft side. Alternatively, the number of passing teeth of the input main gear 11 may be counted.
[0120]
【The invention's effect】
As described above, according to the present invention, it is possible to accurately perform a fault diagnosis of the gear stage detector, and to exhibit an excellent effect of improving reliability.
[Brief description of the drawings]
FIG. 1 is a skeleton diagram showing a power transmission device for a vehicle according to an embodiment.
FIG. 2 is a hydraulic circuit diagram showing a hydraulic pressure supply device according to the present embodiment.
FIG. 3 is a characteristic diagram of the hydraulic pressure supply device according to the present embodiment.
FIG. 4 is a configuration diagram illustrating an electronic control device according to the present embodiment.
FIG. 5 is a time chart showing the contents of clutch connection control according to the present embodiment and is a case of upshifting.
FIG. 6 is a time chart showing the contents of clutch connection control according to the present embodiment, in the case of downshifting.
FIG. 7 is a time chart showing the contents of clutch connection control according to the present embodiment and is a case of a garage shift.
FIG. 8 is a step duty calculation map during upshifting according to the present embodiment.
FIG. 9 is a step duty calculation map at the time of downshift according to the present embodiment.
FIG. 10 is a step duty calculation map during a garage shift according to the present embodiment.
FIG. 11 is a configuration diagram showing an embodiment of a gear position detection device.
12 is a diagram schematically illustrating the gear stage detection device of FIG. 11. FIG.
FIG. 13 shows specific values such as the gear ratio of each gear stage used for gear stage detection.
FIG. 14 is a configuration diagram showing another embodiment of the gear position detection device.
FIG. 15 is a graph showing a relationship between a vehicle speed and a transmission rotational speed in consideration of a correction coefficient range.
FIG. 16 is a graph showing the relationship between general vehicle speed and transmission rotation speed.
FIG. 17 is a diagram showing a configuration of a gear position sensor according to the present embodiment.
FIG. 18 is a map used for failure determination of a gear stage detector.
[Explanation of symbols]
8 Input shaft
9 Output shaft
16 Electronic control unit (ECU)
20 Transmission rotation sensor
21 Vehicle speed sensor
24 Gear position sensor
31 Shift stroke sensor
Gear ratio of GR gear stage
Nd constant value
Number of PTM vehicle speed pulses
SW1, SW2 select switch
T / M transmission

Claims (5)

A gear detector including a sensor, a switch, and the like for detecting that the transmission has entered a predetermined gear stage; and a failure detection means for detecting a failure of the gear detector in the gear stage. A failure determination means for measuring the time during which the failure has been detected and finally determining that the gear detector has failed when the time reaches a predetermined time; and a gear from the gear during the time measurement. A failure diagnosis apparatus for a gear stage detector, comprising: holding means for holding a time value at the time of the gear release operation when the gear release operation is performed. 2. The gear stage according to claim 1, wherein the failure determination means restarts the time measurement from the held time value when a failure is detected by the failure detection means even after being re-entered in the gear stage. Detector fault diagnosis device. 3. The gear stage detector failure diagnosis apparatus according to claim 1, wherein the failure determination means reduces the time or sets the initial value when no failure is detected by the failure detection means. The failure detection means uses the output pulse of a sensor provided on the input / output shaft side of the transmission, and detects the gear stage based on the other pulse number when one reference pulse is output as a unit number. When the gear stage detecting means and the detected gear stage are different from the gear stage detected by the gear stage detector, if the gear stage detector is out of order, it is detected by this. Determine the wrong gear stage, divide the number of the other pulse by the gear ratio of the wrong gear stage, and when the value almost matches the predetermined value, finally the gear stage detector The gear stage detector failure diagnosis apparatus according to any one of claims 1 to 3, further comprising determination means for determining a failure. The gear stage detector failure diagnosis apparatus according to any one of claims 1 to 4, wherein a count value of a counter that can be increased or decreased by a unit number every predetermined time is used as the substitute value of the time.

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