JPH04318245A - Air-fuel ratio study control device for internal combustion engine - Google Patents
Air-fuel ratio study control device for internal combustion engineInfo
- Publication number
- JPH04318245A JPH04318245A JP8542191A JP8542191A JPH04318245A JP H04318245 A JPH04318245 A JP H04318245A JP 8542191 A JP8542191 A JP 8542191A JP 8542191 A JP8542191 A JP 8542191A JP H04318245 A JPH04318245 A JP H04318245A
- Authority
- JP
- Japan
- Prior art keywords
- air
- fuel ratio
- learning
- correction value
- fuel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000000446 fuel Substances 0.000 title claims abstract description 260
- 238000002485 combustion reaction Methods 0.000 title claims description 9
- 238000012937 correction Methods 0.000 claims abstract description 162
- 238000001514 detection method Methods 0.000 claims description 10
- 239000000203 mixture Substances 0.000 claims description 6
- 238000002347 injection Methods 0.000 abstract description 36
- 239000007924 injection Substances 0.000 abstract description 36
- 238000000034 method Methods 0.000 description 21
- 230000008569 process Effects 0.000 description 20
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 11
- 229910052760 oxygen Inorganic materials 0.000 description 11
- 239000001301 oxygen Substances 0.000 description 11
- 230000007423 decrease Effects 0.000 description 7
- 230000008859 change Effects 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 239000007789 gas Substances 0.000 description 4
- 230000004044 response Effects 0.000 description 4
- 239000000498 cooling water Substances 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000008901 benefit Effects 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
Landscapes
- Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
- Combined Controls Of Internal Combustion Engines (AREA)
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は内燃機関の空燃比学習制
御装置に関し、詳しくは、自動車用内燃機関における吸
入混合気の空燃比が目標空燃比に一致するように燃料供
給量を補正するための空燃比学習制御に関する。[Field of Industrial Application] The present invention relates to an air-fuel ratio learning control device for an internal combustion engine, and more specifically, for correcting the amount of fuel supplied so that the air-fuel ratio of an intake air-fuel mixture in an automobile internal combustion engine matches a target air-fuel ratio. Regarding air-fuel ratio learning control.
【０００２】0002
【従来の技術】従来、空燃比フィードバック補正制御機
能をもつ電子制御燃料噴射装置を備えた内燃機関におい
ては、特開昭６０−９０９４４号公報，特開昭６１−１
９０１４２号公報等に開示されるように、空燃比の学習
制御が採用されているものがある。[Prior Art] Conventionally, in an internal combustion engine equipped with an electronically controlled fuel injection device having an air-fuel ratio feedback correction control function, Japanese Patent Laid-Open No. 60-90944 and Japanese Patent Laid-Open No. 61-1
As disclosed in Japanese Patent No. 90142 and the like, there are some that employ learning control of the air-fuel ratio.
【０００３】空燃比フィードバック補正制御は、目標空
燃比（例えば理論空燃比）に対する実際の空燃比のリッ
チ・リーンを機関排気系に設けた酸素センサにより判別
し、該判別結果に基づき空燃比フィードバック補正係数
ＬＭＤを比例・積分制御などにより設定し、機関に吸入
される空気量に関与する機関運転状態のパラメータ（例
えば吸入空気流量Ｑと機関回転速度Ｎ）から算出される
基本燃料噴射量Ｔｐを、前記空燃比フィードバック補正
係数ＬＭＤで補正することで、実際の空燃比を目標空燃
比にフィードバック制御するものである。Air-fuel ratio feedback correction control uses an oxygen sensor installed in the engine exhaust system to determine whether the actual air-fuel ratio is rich or lean with respect to a target air-fuel ratio (for example, stoichiometric air-fuel ratio), and performs air-fuel ratio feedback correction based on the determination result. The coefficient LMD is set by proportional/integral control, etc., and the basic fuel injection amount Tp is calculated from engine operating state parameters (for example, intake air flow rate Q and engine rotational speed N) that are related to the amount of air taken into the engine. By correcting with the air-fuel ratio feedback correction coefficient LMD, the actual air-fuel ratio is feedback-controlled to the target air-fuel ratio.
【０００４】ここで、前記空燃比フィードバック補正係
数ＬＭＤの基準値（目標収束値）からの偏差を、複数に
区分された運転領域毎に学習して学習補正係数ＫＢＬＲ
Ｃ（空燃比学習補正値）を定め、基本燃料噴射量Ｔｐを
前記学習補正係数ＫＢＬＲＣ により補正して、補正係
数ＬＭＤなしで得られるベース空燃比が略目標空燃比に
一致するようにし、空燃比フィードバック制御中は更に
前記補正係数ＬＭＤで補正して燃料噴射量Ｔｉを演算す
るものである。[0004] Here, the deviation of the air-fuel ratio feedback correction coefficient LMD from the reference value (target convergence value) is learned for each of the plurality of operating regions and is determined as a learning correction coefficient KBLR.
C (air-fuel ratio learning correction value) is determined, and the basic fuel injection amount Tp is corrected by the learning correction coefficient KBLRC so that the base air-fuel ratio obtained without the correction coefficient LMD approximately matches the target air-fuel ratio, and the air-fuel ratio During feedback control, the fuel injection amount Ti is calculated by further correcting it using the correction coefficient LMD.
【０００５】これにより、運転条件毎に異なる補正要求
に対応した燃料補正が行え、空燃比フィードバック補正
係数ＬＭＤを基準値付近に安定させて、空燃比制御性を
向上させることができる。[0005] As a result, fuel correction can be performed in response to different correction requests for each operating condition, and the air-fuel ratio feedback correction coefficient LMD can be stabilized near the reference value, thereby improving air-fuel ratio controllability.
【０００６】[0006]
【発明が解決しようとする課題】ところで、前記運転領
域別の空燃比学習補正係数ＫＢＬＲＣ は、前述のよう
に運転条件の違いによる空燃比補正要求の違いに対応す
べく設定されるものであるから、運転領域を極力細かく
区分して学習させることが望まれる。しかしながら、運
転領域を細かく区分して狭い運転領域毎に学習補正係数
ＫＢＬＲＣ を学習させるようにすると、それぞれの運
転領域における学習機会が減少し、学習の収束性が悪化
すると共に、学習済領域と未学習領域とが混在すること
になって、運転領域間で大きな空燃比段差が発生してし
まう。[Problem to be Solved by the Invention] Incidentally, the air-fuel ratio learning correction coefficient KBLRC for each operating region is set to accommodate differences in air-fuel ratio correction requests due to differences in operating conditions, as described above. , it is desirable to learn by dividing the driving range as finely as possible. However, if the driving area is divided into small areas and the learning correction coefficient KBLRC is learned for each narrow driving area, the learning opportunities in each driving area will decrease, the convergence of learning will deteriorate, and the learned area will be different from the unlearned area. As a result, a large difference in air-fuel ratio occurs between the operating regions.
【０００７】そこで、本出願人は、運転領域の区分数を
異ならせた複数の学習マップを備えるようにし、これら
複数の学習マップの中でより区分数が少なく学習単位の
運転領域がより広い学習マップから学習を行わせ、学習
進行と共により区分数が多く学習単位の運転領域が狭い
学習マップ上での空燃比学習へと移行させるよう構成し
た空燃比学習制御装置を、先に提案した（特願平１−２
８２８８３号参照）。[0007] Therefore, the present applicant has provided a plurality of learning maps with different numbers of divisions in the driving area, and among these plurality of learning maps, a learning map with a smaller number of divisions and a learning unit with a wider driving area is provided. We have previously proposed an air-fuel ratio learning control device that is configured to perform learning from a map and, as learning progresses, to shift to air-fuel ratio learning on a learning map with a larger number of segments and a narrower operating area for each learning unit. Ganhei 1-2
82883).
【０００８】かかる空燃比学習によれば、学習初期は大
きな単位運転領域別に学習させることで学習収束性が確
保され、学習が進行すればより細かな単位運転領域別に
空燃比学習が行われるから、運転条件の違いによる補正
要求の違いに精度良く対応した学習が行える。しかしな
がら、上記のように運転領域別に空燃比学習補正値を記
憶する学習マップを複数備える構成では、多くのメモリ
容量を必要とするという欠点があった。According to such air-fuel ratio learning, learning convergence is ensured by learning in large unit operating regions at the initial stage of learning, and as learning progresses, air-fuel ratio learning is performed in smaller unit operating regions. Learning can be performed that accurately responds to differences in correction requests due to differences in operating conditions. However, the configuration including a plurality of learning maps for storing air-fuel ratio learning correction values for each driving range as described above has a disadvantage in that a large memory capacity is required.
【０００９】本発明は上記問題点に鑑みなされたもので
あり、学習の収束性と空燃比学習精度とを両立させた空
燃比学習を、メモリ容量を節約しつつ実現できるように
することを目的とする。また、運転条件毎に精度良い空
燃比学習を行わせつつ、ベース空燃比の急変時に学習を
速やかに収束させることができるようにすることを目的
とする。The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to realize air-fuel ratio learning that achieves both convergence of learning and accuracy of air-fuel ratio learning while saving memory capacity. shall be. Another object of the present invention is to perform air-fuel ratio learning with high accuracy for each operating condition, and to quickly converge the learning when the base air-fuel ratio suddenly changes.
【００１０】0010
【課題を解決するための手段】そのため本発明にかかる
内燃機関の空燃比学習制御装置は、図１に示すように構
成される。図１において、運転条件検出手段は、機関に
吸入される空気量に関与する運転パラメータを少なくと
も含む機関運転条件を検出し、基本燃料供給量設定手段
は前記検出された機関運転条件に基づいて基本燃料供給
量を設定する。[Means for Solving the Problems] Therefore, an air-fuel ratio learning control device for an internal combustion engine according to the present invention is constructed as shown in FIG. In FIG. 1, the operating condition detecting means detects the engine operating condition including at least an operating parameter related to the amount of air taken into the engine, and the basic fuel supply amount setting means detects the basic fuel supply amount based on the detected engine operating condition. Set the fuel supply amount.
【００１１】また、空燃比フィードバック補正値設定手
段は、空燃比検出手段で検出される機関吸入混合気の空
燃比と目標空燃比とを比較して実際の空燃比を前記目標
空燃比に近づけるように前記基本燃料供給量を補正する
ための空燃比フィードバック補正値を設定する。学習補
正値記憶手段は、機関運転条件に基づき複数に区分され
た運転領域毎に前記基本燃料供給量を補正するための空
燃比学習補正値を書き換え可能に記憶するものであり、
空燃比学習手段は、前記空燃比フィードバック補正値の
目標収束値からの偏差を学習し、前記学習補正値記憶手
段において該当領運転領域に対応して記憶されている前
記空燃比学習補正値を前記偏差を減少させる方向に修正
して書き換える。The air-fuel ratio feedback correction value setting means compares the air-fuel ratio of the engine intake air-fuel mixture detected by the air-fuel ratio detection means with a target air-fuel ratio to bring the actual air-fuel ratio closer to the target air-fuel ratio. An air-fuel ratio feedback correction value for correcting the basic fuel supply amount is set in . The learning correction value storage means rewritably stores an air-fuel ratio learning correction value for correcting the basic fuel supply amount for each of a plurality of operating regions divided based on engine operating conditions,
The air-fuel ratio learning means learns the deviation of the air-fuel ratio feedback correction value from the target convergence value, and the air-fuel ratio learning correction value stored in the learning correction value storage means corresponding to the relevant operating region is used as the air-fuel ratio learning correction value. Correct and rewrite in a direction that reduces the deviation.
【００１２】一方、学習済領域記憶手段は、前記空燃比
フィードバック補正値が目標収束値に略一致するときに
、そのときの前記学習補正値記憶手段上での該当運転領
域を学習済領域として判別し、かかる判別結果を前記学
習補正値記憶手段の各運転領域別に記憶する。また、推
定学習手段は、前記空燃比学習手段により書き換えられ
た該当運転領域の空燃比学習補正値を、前記該当運転領
域に対して運転条件の近い別の運転領域に対応する空燃
比学習補正値として学習補正値記憶手段上の該当運転領
域以外の空燃比学習補正値を書き換える。On the other hand, the learned region storage means, when the air-fuel ratio feedback correction value substantially matches the target convergence value, determines the corresponding operating region on the learned correction value storage means at that time as a learned region. The results of this determination are stored for each operating region in the learning correction value storage means. Further, the estimation learning means converts the air-fuel ratio learning correction value of the relevant operating region rewritten by the air-fuel ratio learning means into an air-fuel ratio learning correction value corresponding to another operating region having operating conditions close to the relevant operating region. As a result, the air-fuel ratio learning correction values other than the corresponding operating range are rewritten on the learning correction value storage means.
【００１３】学習済領域数による推定学習制御手段は、
前記学習済領域記憶手段に記憶される学習済領域数の増
大に応じて前記推定学習手段で空燃比学習補正値が該当
運転領域と共に書き換えられる運転領域の数を減少させ
る。そして、燃料供給量設定手段は、前記基本燃料供給
量，空燃比フィードバック補正値及び学習補正値記憶手
段において該当運転領域に対応して記憶されている空燃
比学習補正値に基づいて最終的な燃料供給量を設定し、
燃料供給制御手段は、前記設定された燃料供給量に基づ
いて燃料供給手段を駆動制御する。[0013] The estimation learning control means based on the number of learned regions is as follows:
In response to an increase in the number of learned regions stored in the learned region storage means, the estimated learning means reduces the number of operating regions in which the air-fuel ratio learning correction value is rewritten together with the corresponding operating region. The fuel supply amount setting means determines the final fuel supply amount based on the basic fuel supply amount, the air-fuel ratio feedback correction value, and the air-fuel ratio learning correction value stored in the learning correction value storage means corresponding to the corresponding operating region. Set the supply amount,
The fuel supply control means drives and controls the fuel supply means based on the set fuel supply amount.
【００１４】ここで、図１に点線で示すように、前記学
習済領域記憶手段及び学習済領域数による推定学習制御
手段に代えて、適正判断手段と適正判断による推定学習
制御手段とを設けて構成しても良い。前記適正判断手段
は、学習補正値記憶手段上において該当運転領域が切り
換わったときの前記空燃比フィードバック補正値の目標
収束値に対する偏差に基づいて空燃比学習の結果の適正
を判断し、適正判断による推定学習制御手段は、前記適
正判断手段で学習結果が不適正であることが判断された
ときに、推定学習手段により該当運転領域と共に空燃比
学習補正値が書き換えられる運転領域の数を最大数とし
、その後学習の進行と共に前記運転領域の数を減少させ
る。Here, as shown by the dotted line in FIG. 1, in place of the learned area storage means and the estimated learning control means based on the number of learned areas, an appropriate judgment means and an estimated learning control means based on the appropriate judgment are provided. It may be configured. The appropriateness determination means determines the appropriateness of the result of air-fuel ratio learning based on the deviation of the air-fuel ratio feedback correction value from the target convergence value when the corresponding operating region is switched on the learning correction value storage means, and makes an appropriate judgment. The estimated learning control means sets a maximum number of operating regions in which the air-fuel ratio learning correction value is rewritten together with the corresponding operating region by the estimated learning means when the learning result is determined to be inappropriate by the appropriateness determining means. Then, as learning progresses, the number of operating regions is decreased.
【００１５】[0015]
【作用】前記学習補正値記憶手段上の運転条件の近い運
転領域間では、空燃比学習補正値の要求レベルも近似す
るはずである。そこで、学習済領域数が少ないときには
、該当運転領域に運転条件が近い他の運転領域において
も、空燃比学習補正値の要求レベルとしては略同等であ
ると見做し、該当運転領域に対応する空燃比学習補正値
を周辺の運転領域にも充当させる。従って、学習済領域
数が少ない学習初期に、学習機会の得られない運転領域
の空燃比学習補正値がそのままに放置されることがなく
、少なくとも要求値に近いレベルに速やかに学習させる
ことができ、学習の収束性が確保される。また、学習済
領域が増大すると、該当運転領域と共に書き換えられる
運転領域の数が減少するから、個々の運転領域別の要求
に細かく対応した学習が可能となる。[Operation] The required level of the air-fuel ratio learning correction value is supposed to be similar between operating regions in which the operating conditions are similar on the learning correction value storage means. Therefore, when the number of learned regions is small, it is assumed that the required level of the air-fuel ratio learning correction value is approximately the same even in other operating regions whose operating conditions are close to the corresponding operating region, and the required level of the air-fuel ratio learning correction value is considered to be approximately the same, and the required level of the air-fuel ratio learning correction value is assumed to be approximately the same. The air-fuel ratio learning correction value is also applied to the surrounding driving range. Therefore, at the beginning of learning when the number of learned regions is small, the air-fuel ratio learning correction value for the operating region where no learning opportunity is available will not be left as is, and at least it can be quickly learned to a level close to the required value. , the convergence of learning is ensured. Furthermore, as the number of learned regions increases, the number of operating regions that are rewritten together with the relevant operating region decreases, making it possible to perform learning that precisely corresponds to the requirements of each individual operating region.
【００１６】一方、学習補正値記憶手段上において該当
運転領域が切り換わったときに、空燃比フィードバック
補正値を目標収束値から変化させる必要が生じたときに
は、切り換え後の該当運転領域に対応する空燃比学習補
正値が不適正であると予測される。そこで、学習補正値
記憶手段上において該当運転領域が切り換わったときの
前記空燃比フィードバック補正値の目標収束値に対する
偏差に基づいて空燃比学習結果の適正を判断し、学習結
果が不適切である場合には速やかな収束を図るために該
当運転領域と共に書き換えられる運転領域数を最大数と
し、学習の進行と共に前記運転領域の数を減少させて、
運転領域別の精度良い学習が行えるようにする。On the other hand, if it is necessary to change the air-fuel ratio feedback correction value from the target convergence value when the corresponding operating region is switched on the learning correction value storage means, the air-fuel ratio feedback correction value corresponding to the corresponding operating region after switching is changed. It is predicted that the fuel ratio learning correction value is inappropriate. Therefore, the suitability of the air-fuel ratio learning result is determined based on the deviation of the air-fuel ratio feedback correction value from the target convergence value when the relevant operating region is switched on the learning correction value storage means, and the learning result is determined to be inappropriate. In this case, in order to achieve rapid convergence, the number of operating regions that are rewritten together with the corresponding operating region is set to the maximum number, and the number of operating regions is reduced as learning progresses,
To enable accurate learning for each driving area.
【００１７】[0017]
【実施例】以下に本発明の実施例を説明する。一実施例
を示す図２において、内燃機関１にはエアクリーナ２か
ら吸気ダクト３，スロットル弁４及び吸気マニホールド
５を介して空気が吸入される。吸気マニホールド５の各
ブランチ部には、各気筒別に燃料供給手段としての燃料
噴射弁６が設けられている。この燃料噴射弁６は、ソレ
ノイドに通電されて開弁し、通電停止されて閉弁する電
磁式燃料噴射弁であって、後述するコントロールユニッ
ト１２からの駆動パルス信号により通電されて開弁し、
図示しない燃料ポンプから圧送されてプレッシャレギュ
レータにより所定の圧力に調整された燃料を、機関１に
間欠的に噴射供給する。[Examples] Examples of the present invention will be described below. In FIG. 2 showing one embodiment, air is taken into an internal combustion engine 1 from an air cleaner 2 via an intake duct 3, a throttle valve 4, and an intake manifold 5. As shown in FIG. Each branch of the intake manifold 5 is provided with a fuel injection valve 6 as a fuel supply means for each cylinder. The fuel injection valve 6 is an electromagnetic fuel injection valve that opens when the solenoid is energized and closes when the energization is stopped, and opens when the solenoid is energized by a drive pulse signal from the control unit 12,
The engine 1 is intermittently injected with fuel that is pressure-fed from a fuel pump (not shown) and adjusted to a predetermined pressure by a pressure regulator.
【００１８】機関１の各燃焼室には点火栓７が設けられ
ていて、これにより火花点火して混合気を着火燃焼させ
る。そして、機関１からは、排気マニホールド８，排気
ダクト９，三元触媒１０及びマフラー１１を介して排気
が排出される。コントロールユニット１２は、ＣＰＵ，
ＲＯＭ，ＲＡＭ，Ａ／Ｄ変換器及び入出力インタフェイ
ス等を含んで構成されるマイクロコンピュータを備え、
各種のセンサからの入力信号を受け、後述の如く演算処
理して、燃料噴射弁６の作動を制御する。Each combustion chamber of the engine 1 is provided with an ignition plug 7, which ignites a spark to ignite and burn the air-fuel mixture. Then, exhaust gas is discharged from the engine 1 via an exhaust manifold 8, an exhaust duct 9, a three-way catalyst 10, and a muffler 11. The control unit 12 includes a CPU,
Equipped with a microcomputer including ROM, RAM, A/D converter, input/output interface, etc.
It receives input signals from various sensors, performs arithmetic processing as described later, and controls the operation of the fuel injection valve 6.
【００１９】前記各種のセンサとしては、吸気ダクト３
中にエアフローメータ１３が設けられていて、機関１の
吸入空気流量Ｑに応じた信号を出力する。また、クラン
ク角センサ１４が設けられていて、本実施例の４気筒の
場合、クランク角１８０ °毎の基準信号ＲＥＦと、ク
ランク角１°又は２°毎の単位信号ＰＯＳとを出力する
。ここで、基準信号ＲＥＦの周期、或いは、所定時間内
における単位信号ＰＯＳの発生数を計測することにより
、機関回転速度Ｎを算出できる。また、機関１のウォー
タジャケットの冷却水温度Ｔｗを検出する水温センサ１
５が設けられている。The various sensors mentioned above include the intake duct 3
An air flow meter 13 is provided therein, and outputs a signal corresponding to the intake air flow rate Q of the engine 1. Further, a crank angle sensor 14 is provided, and in the case of the four-cylinder engine of this embodiment, outputs a reference signal REF for every 180 degrees of crank angle and a unit signal POS for every 1 degree or 2 degrees of crank angle. Here, the engine rotational speed N can be calculated by measuring the period of the reference signal REF or the number of occurrences of the unit signal POS within a predetermined period of time. Also, a water temperature sensor 1 that detects the cooling water temperature Tw of the water jacket of the engine 1.
5 is provided.
【００２０】ここで、上記エアフローメータ１３，クラ
ンク角センサ１４，水温センサ１５等が本実施例におけ
る運転条件検出手段に相当し、機関に吸入される空気量
に関与する運転パラメータとは、本実施例において吸入
空気流量Ｑ及び機関回転速度Ｎである。また、排気マニ
ホールド８の集合部に空燃比検出手段としての酸素セン
サ１６が設けられ、排気中の酸素濃度を介して吸入混合
気の空燃比を検出する。前記酸素センサ１６は、排気中
の酸素濃度が理論空燃比（本実施例における目標空燃比
）を境に急変することを利用して、実際の空燃比の理論
空燃比に対するリッチ・リーンを検出する公知のもので
あり、本実施例では、理論空燃比よりもリッチ空燃比で
あるときには比較的高い電圧信号を出力し、逆にリーン
空燃比であるときには０Ｖ付近の低い電圧信号を出力す
るものとする。Here, the air flow meter 13, crank angle sensor 14, water temperature sensor 15, etc. correspond to the operating condition detection means in this embodiment, and the operating parameters related to the amount of air taken into the engine are In the example, these are the intake air flow rate Q and the engine rotation speed N. Further, an oxygen sensor 16 as an air-fuel ratio detecting means is provided at the gathering part of the exhaust manifold 8, and detects the air-fuel ratio of the intake air-fuel mixture via the oxygen concentration in the exhaust gas. The oxygen sensor 16 detects whether the actual air-fuel ratio is rich or lean with respect to the stoichiometric air-fuel ratio by utilizing the fact that the oxygen concentration in the exhaust gas changes suddenly beyond the stoichiometric air-fuel ratio (target air-fuel ratio in this embodiment). This is a well-known method, and in this embodiment, a relatively high voltage signal is output when the air-fuel ratio is richer than the stoichiometric air-fuel ratio, and a low voltage signal near 0 V is output when the air-fuel ratio is leaner than the stoichiometric air-fuel ratio. do.
【００２１】ここにおいて、コントロールユニット１２
に内蔵されたマイクロコンピュータのＣＰＵは、図３〜
図７のフローチャートにそれぞれ示すＲＯＭ上のプログ
ラムに従って演算処理を行い、空燃比フィードバック補
正制御及び運転領域毎の空燃比学習補正制御を実行しつ
つ燃料噴射量Ｔｉを設定し、機関１への燃料供給を制御
する。[0021] Here, the control unit 12
The CPU of the microcomputer built into the
Arithmetic processing is performed according to the programs on the ROM shown in the flowchart of FIG. 7, and the fuel injection amount Ti is set while executing air-fuel ratio feedback correction control and air-fuel ratio learning correction control for each operating region, and fuel is supplied to the engine 1. control.
【００２２】尚、本実施例において、基本燃料供給量設
定手段，燃料供給量設定手段，燃料供給制御手段，空燃
比フィードバック補正値設定手段，空燃比学習手段，推
定学習手段，学習済領域記憶手段，学習済領域数による
推定学習制御手段，適正判断手段，適正判断による推定
学習制御手段，学習補正値記憶手段としての機能は、コ
ントロールユニット１２が備えている。In this embodiment, basic fuel supply amount setting means, fuel supply amount setting means, fuel supply control means, air-fuel ratio feedback correction value setting means, air-fuel ratio learning means, estimation learning means, and learned area storage means , an estimation learning control means based on the number of learned regions, an appropriate judgment means, an estimation learning control means based on an appropriate judgment, and a learning correction value storage means.
【００２３】図３のフローチャートに示すプログラムは
、基本燃料噴射量（基本燃料供給量）Ｔｐに乗算される
空燃比フィードバック補正係数ＬＭＤ（空燃比フィード
バック補正値）を、比例・積分制御により設定するプロ
グラムであり、機関１の１回転（１ｒｅｖ）毎に実行さ
れる。まず、ステップ１（図中ではＳ１としてある。以
下同様）では、酸素センサ（Ｏ２ ／Ｓ）１６から排気
中の酸素濃度に応じて出力される電圧信号を読み込む。The program shown in the flowchart of FIG. 3 is a program for setting the air-fuel ratio feedback correction coefficient LMD (air-fuel ratio feedback correction value) by which the basic fuel injection amount (basic fuel supply amount) Tp is multiplied by proportional/integral control. This is executed every one revolution (1 rev) of the engine 1. First, in step 1 (indicated as S1 in the figure; the same applies hereinafter), a voltage signal output from the oxygen sensor (O2/S) 16 according to the oxygen concentration in the exhaust gas is read.
【００２４】そして、次のステップ２では、ステップ１
で読み込んだ酸素センサ１６からの電圧信号と、目標空
燃比（理論空燃比）相当のスライスレベル（例えば５０
０ｍＶ）とを比較する。酸素センサ１６からの電圧信号
がスライスレベルよりも大きく空燃比が理論空燃比より
もリッチであると判別されたときには、ステップ３へ進
み、今回のリッチ判別が初回であるか否かを判別する。[0024] Then, in the next step 2, step 1
The voltage signal from the oxygen sensor 16 read in and the slice level (for example, 50
0 mV). When it is determined that the voltage signal from the oxygen sensor 16 is greater than the slice level and the air-fuel ratio is richer than the stoichiometric air-fuel ratio, the process proceeds to step 3, where it is determined whether or not the current rich determination is the first.
【００２５】リッチ判別が初回であるときには、ステッ
プ４へ進んで前回までに設定されている空燃比フィード
バック補正係数ＬＭＤを最大値ａにセットする。次のス
テップ５では、前回までの補正係数ＬＭＤから所定の比
例定数Ｐだけ減算して補正係数ＬＭＤの減少制御を図る
。また、ステップ６では、補正係数ＬＭＤの比例制御を
実行したこと、換言すれば、空燃比のリッチ・リーン反
転があったことが判別されるようにフラグＦＰに１をセ
ットする。When the rich determination is made for the first time, the process proceeds to step 4, where the air-fuel ratio feedback correction coefficient LMD set up to the previous time is set to the maximum value a. In the next step 5, a predetermined proportionality constant P is subtracted from the previous correction coefficient LMD to control the correction coefficient LMD to decrease. Further, in step 6, a flag FP is set to 1 so that it is determined that the proportional control of the correction coefficient LMD has been executed, in other words, that there has been a rich/lean reversal of the air-fuel ratio.
【００２６】一方、ステップ３で、リッチ判別が初回で
ないと判別されたときには、ステップ７へ進み、積分定
数Ｉに最新の燃料噴射量Ｔｉを乗算した値を、前回まで
の補正係数ＬＭＤから減算して補正係数ＬＭＤを更新す
る。また、ステップ２で酸素センサ１６からの電圧信号
がスライスレベルよりも小さく空燃比が目標に対してリ
ーンであると判別されたときには、リッチ判別のときと
同様にして、まず、ステップ８で今回のリーン判別が初
回であるか否かを判別し、初回であるときには、ステッ
プ９へ進んで前回までの補正係数ＬＭＤを最小値ｂにセ
ットする。On the other hand, if it is determined in step 3 that the rich determination is not the first time, the process proceeds to step 7, and the value obtained by multiplying the integral constant I by the latest fuel injection amount Ti is subtracted from the previous correction coefficient LMD. and updates the correction coefficient LMD. In addition, when it is determined in step 2 that the voltage signal from the oxygen sensor 16 is smaller than the slice level and that the air-fuel ratio is lean relative to the target, first, in step 8, the air-fuel ratio is determined to be lean relative to the target. It is determined whether or not the lean determination is the first time, and if it is the first time, the process advances to step 9 and the correction coefficient LMD up to the previous time is set to the minimum value b.
【００２７】次のステップ１０では、前回までの補正係
数ＬＭＤに比例定数Ｐを加算して更新することにより燃
料噴射量Ｔｉの増量補正を図り、ステップ１１では、比
例制御が実行されたことが判別されるようにフラグＦＰ
に１をセットする。ステップ８でリーン判別が初回でな
いと判別されたときには、ステップ１２へ進み、積分定
数Ｉに最新の燃料噴射量Ｔｉを乗算した値を、前回まで
の補正係数ＬＭＤに加算し、補正係数ＬＭＤを徐々に増
大させる。In the next step 10, the fuel injection amount Ti is increased by updating the previous correction coefficient LMD by adding the proportionality constant P, and in step 11, it is determined that the proportional control has been executed. Flag FP to be
Set 1 to . If it is determined in step 8 that the lean determination is not the first time, the process proceeds to step 12, where the value obtained by multiplying the integral constant I by the latest fuel injection amount Ti is added to the previous correction coefficient LMD, and the correction coefficient LMD is gradually increased. increase to
【００２８】リッチ・リーン判別の初回で補正係数ＬＭ
Ｄの比例制御を実行したときには、更に、空燃比学習制
御に関わる後述するような各種処理を行う。まず、ステ
ップ１３では、複数に区分された運転領域別に空燃比学
習補正係数ＫＢＬＲＣ を更新可能に記憶する空燃比学
習マップ上における学習済領域数の増大に応じて減少設
定され、ゼロがセットされているときに略全ての運転領
域で学習が終了していることを示す推定学習カウンタＺ
Ｚがゼロであるか否かを判別する。[0028] At the first time of rich/lean discrimination, the correction coefficient LM
When proportional control D is executed, various processes related to air-fuel ratio learning control, which will be described later, are further performed. First, in step 13, the air-fuel ratio learning correction coefficient KBLRC is set to decrease according to the increase in the number of learned regions on the air-fuel ratio learning map that stores the air-fuel ratio learning correction coefficient KBLRC in an updatable manner for each operating region divided into a plurality of regions, and is set to zero. Estimated learning counter Z indicates that learning has been completed in almost all driving ranges when
Determine whether Z is zero.
【００２９】尚、前記推定学習カウンタＺＺの設定制御
については、図４のフローチャートに従って後に詳細に
説明する。また、本実施例における学習終了は、空燃比
フィードバック補正係数ＬＭＤによる補正なしで目標空
燃比（理論空燃比）が得られている状態、換言すれば、
空燃比フィードバック補正係数ＬＭＤが目標収束値＝１
．０ に略一致しているときに、そのときの該当運転領
域が学習済であると判断するものとする。The setting control of the estimated learning counter ZZ will be explained in detail later in accordance with the flowchart of FIG. Furthermore, the completion of learning in this embodiment means a state in which the target air-fuel ratio (theoretical air-fuel ratio) is obtained without correction by the air-fuel ratio feedback correction coefficient LMD, in other words,
Air-fuel ratio feedback correction coefficient LMD is target convergence value = 1
．． 0, it is determined that the relevant driving region at that time has been learned.
【００３０】前記学習マップは、本実施例において基本
燃料噴射量Ｔｐと機関回転速度Ｎとに基づいて運転領域
を１６×１６の２５６ 領域に区分し、これら区分され
た運転領域毎に学習補正係数ＫＢＬＲＣ （初期値＝１
．０ ）を更新可能に記憶するものである。ステップ１
３で推定学習カウンタＺＺにゼロがセットされていると
判別されたときには、ステップ１４へ進み、前回比例制
御を行ったときの学習マップ上の該当運転領域と、現在
の該当運転領域とが同一であるか否かを判別する。In this embodiment, the learning map divides the operating region into 256 regions (16×16) based on the basic fuel injection amount Tp and the engine speed N, and sets the learning correction coefficient for each of these divided operating regions. KBLRC (initial value=1
．． 0) is stored in an updatable manner. Step 1
If it is determined in step 3 that the estimated learning counter ZZ is set to zero, the process proceeds to step 14, where it is determined that the corresponding operating area on the learning map when proportional control was performed last time is the same as the current applicable operating area. Determine whether it exists or not.
【００３１】ここで、該当領域が切り換わったことが判
別されたときには、ステップ１５へ進み、前記ステップ
４，９で設定された補正係数ＬＭＤの最大値ａ，最小値
ｂの平均値と、補正係数ＬＭＤの目標収束値（＝１．０
）との偏差の絶対値に基づいて、学習結果の不適正度
合いを示すΔストレスを設定する。即ち、ステップ１３
で学習が全運転領域において略終了していることが判別
されたから、学習が精度良く行われていれば、該当運転
領域が切り換わっても補正係数ＬＭＤは略目標収束値（
＝１．０ ）付近に安定しているはずであり、目標収束
値に対する偏差が大きいときほど、学習結果と要求レベ
ルとの間に差があると推定できる。そこで、前記ステッ
プ１５では、補正係数ＬＭＤの平均値が目標収束値に対
して大きな偏差を有しているときほど前記Δストレスを
大きく設定し、該Δストレスの増大が学習結果の不適正
さの増大を示すようにしてある。Here, when it is determined that the corresponding area has been switched, the process proceeds to step 15, and the average value of the maximum value a and minimum value b of the correction coefficient LMD set in steps 4 and 9, and the correction Target convergence value of coefficient LMD (=1.0
), Δstress indicating the degree of inappropriateness of the learning result is set. That is, step 13
Since it was determined that learning was almost completed in all operating regions, if learning was performed with high accuracy, the correction coefficient LMD would remain approximately at the target convergence value (
= 1.0 ), and it can be estimated that the larger the deviation from the target convergence value, the greater the difference between the learning result and the required level. Therefore, in step 15, the Δstress is set to be larger when the average value of the correction coefficient LMD has a larger deviation from the target convergence value, and an increase in the Δstress may cause inappropriate learning results. It is designed to show the increase.
【００３２】ステップ１５で設定されたΔストレスは、
次のステップ１６で前回までの積算値「ストレス」に加
算され、この加算結果が新たに「ストレス」にセットさ
れ、前記Δストレスが補正係数ＬＭＤの比例制御毎に積
算されるようにしてある。従って、例えばエアフローメ
ータ１３や燃料噴射弁６の劣化によってベース空燃比が
全体的に変化し、学習済の学習補正係数ＫＢＬＲＣによ
る補正のみでは目標空燃比が得られず補正係数ＬＭＤに
よる補正が必要な状態になった場合には、学習マップ上
での該当運転領域の切り換え毎に比較的大きなΔストレ
スが設定され、これが順次積算されることによって、急
激に前記「ストレス」は増大されることになる。そこで
、後述するように前記「ストレス」が所定レベル以上に
なったときには、学習済の結果が不適正であると判断し
、空燃比学習を最初からやり直すようにしてある。The Δ stress set in step 15 is
In the next step 16, it is added to the previous integrated value "stress", and this addition result is newly set to "stress", so that the Δ stress is integrated every time the correction coefficient LMD is proportionally controlled. Therefore, for example, if the base air-fuel ratio changes overall due to deterioration of the air flow meter 13 or fuel injection valve 6, the target air-fuel ratio cannot be obtained only by correction using the learned correction coefficient KBLRC, and correction using the correction coefficient LMD is necessary. In this case, a relatively large Δ stress is set each time the corresponding driving region is switched on the learning map, and as this is sequentially integrated, the "stress" is rapidly increased. . Therefore, as will be described later, when the "stress" exceeds a predetermined level, it is determined that the learned result is inappropriate, and the air-fuel ratio learning is restarted from the beginning.
【００３３】図４及び図５のフローチャートに示すプロ
グラムは、運転領域別の学習補正係数ＫＢＬＲＣ を更
新設定する空燃比学習プログラムであり、所定微小時間
（例えば１０ｍｓ）毎に実行される。まず、ステップ２
１では、前記図３のフローチャートにおいて補正係数Ｌ
ＭＤの比例制御が行われたときに１がセットされるフラ
グＦＰの判別を行い、フラグＦＰにゼロがセットされて
いるときには、そのまま本プログラムを終了させ、フラ
グＦＰに１がセットされているときには、ステップ２２
でフラグＦＰをゼロリセットしてから、空燃比学習に関
わるステップ２３以降の処理へ進む。従って、後述する
空燃比学習は、補正係数ＬＭＤの比例制御毎（空燃比の
リッチ・リーン反転毎）に実行されるようにしてある。The program shown in the flowcharts of FIGS. 4 and 5 is an air-fuel ratio learning program that updates and sets the learning correction coefficient KBLRC for each operating region, and is executed at predetermined minute intervals (for example, 10 ms). First, step 2
1, the correction coefficient L in the flowchart of FIG.
Determine the flag FP that is set to 1 when MD proportional control is performed, and if the flag FP is set to zero, terminate this program as it is, and if the flag FP is set to 1. , step 22
After resetting the flag FP to zero, the process proceeds to step 23 and subsequent steps related to air-fuel ratio learning. Therefore, the air-fuel ratio learning described later is executed every time the correction coefficient LMD is proportionally controlled (every time the air-fuel ratio is reversed between rich and lean).
【００３４】ステップ２３では、最新に演算された基本
燃料噴射量Ｔｐと機関回転速度Ｎとに基づいて、現在の
運転条件が該当する学習マップ上での運転領域（該当運
転領域）を、格子位置〔Ｉ〕〔Ｋ〕として特定する。次
のステップ２４では、補正係数ＬＭＤの平均値（ａ＋ｂ
）／２が略１．０ であるか否かを判別する。補正係数
ＬＭＤの平均値が略１．０ であるときには、学習補正
係数ＫＢＬＲＣ のみの補正によって略目標空燃比が得
られている状態であって、現在の運転条件が該当する学
習マップ上の領域に対応する学習補正係数ＫＢＬＲＣ
が適正であると推察される。そこで、ステップ２５へ進
んで該当運転領域〔Ｉ〕〔Ｋ〕に対応する学習済フラグ
Ｆｌａｇ 〔Ｉ〕〔Ｋ〕に１をセットし、前記学習済フ
ラグＦｌａｇ に１がセットされている領域が学習済領
域であると判別されるようにする。In step 23, based on the most recently calculated basic fuel injection amount Tp and engine rotational speed N, the operating area (corresponding operating area) on the learning map to which the current operating conditions apply is determined by the grid position. [I] [K]. In the next step 24, the average value (a+b
)/2 is approximately 1.0. When the average value of the correction coefficient LMD is approximately 1.0, it means that approximately the target air-fuel ratio has been obtained by correcting only the learning correction coefficient KBLRC, and the current operating condition falls within the area on the learning map to which it corresponds. Corresponding learning correction coefficient KBLRC
is presumed to be appropriate. Therefore, the process proceeds to step 25, where the learned flag Flag [I] [K] corresponding to the corresponding operation region [I] [K] is set to 1, and the region for which the learned flag Flag is set to 1 is learned. The area is determined to be a completed area.
【００３５】ステップ２６では、後述する図６のフロー
チャートに示すプログラムにおいて、前記学習済フラグ
Ｆｌａｇ に基づき検出される学習マップ上の２５６
領域中での学習済領域数Ｓｔａｔｕｓ に基づいて、前
記推定学習カウンタＺＺを設定する。ここで、前記推定
学習カウンタＺＺは、学習済領域数Ｓｔａｔｕｓ が多
くなるに従って減少設定され、学習済領域数Ｓｔａｔｕ
ｓ が最大数である２５６ 付近である場合にはゼロに
設定される。At step 26, in the program shown in the flowchart of FIG. 6, which will be described later, 256
The estimated learning counter ZZ is set based on the number of learned areas Status in the area. Here, the estimated learning counter ZZ is set to decrease as the number of learned regions Status increases, and the estimated learning counter ZZ is set to decrease as the number of learned regions Status increases.
If s is around the maximum number of 256, it is set to zero.
【００３６】前記推定学習カウンタＺＺは、学習マップ
上の２５６ 領域中の１つの該当運転領域の学習補正係
数ＫＢＬＲＣ を書き換えるときに、この該当運転領域
に対応する学習補正係数ＫＢＬＲＣ をそのまま充当さ
せる運転条件の近い他の領域数を決定するパラメータで
あり、推定学習カウンタＺＺがゼロであるときには、該
当運転領域のみが学習されるが、前記推定学習カウンタ
ＺＺの増大に応じて一度に学習補正係数ＫＢＬＲＣ が
更新される領域数が増大する。即ち、学習済領域数の増
大に応じて徐々に一度に学習される運転領域範囲が狭め
られるようにしてある。The estimated learning counter ZZ is a driving condition in which, when rewriting the learning correction coefficient KBLRC of one of the 256 areas on the learning map, the learning correction coefficient KBLRC corresponding to this corresponding driving area is applied as is. This is a parameter that determines the number of other regions close to The number of updated areas increases. That is, as the number of learned regions increases, the range of driving regions learned at one time is gradually narrowed.
【００３７】ステップ２７以降には、上記のように推定
学習カウンタＺＺに応じた空燃比学習にかかる各種処理
が設定されている。ステップ２７では、学習マップ上の
２５６ 領域の中の該当運転領域に対応して記憶されて
いる学習補正係数ＫＢＬＲＣ 〔Ｉ〕〔Ｋ〕に対して、
補正係数ＬＭＤの平均値の目標収束値（＝１．０ ）に
対する偏差の所定割合（本実施例では１／８）を加算し
、該加算結果を新たな学習補正係数ＫＢＬＲＣ として
設定する。After step 27, various processes related to air-fuel ratio learning according to the estimated learning counter ZZ are set as described above. In step 27, for the learning correction coefficients KBLRC [I] [K] stored corresponding to the corresponding driving region among the 256 regions on the learning map,
A predetermined ratio (1/8 in this embodiment) of the deviation of the average value of the correction coefficient LMD from the target convergence value (=1.0) is added, and the addition result is set as a new learning correction coefficient KBLRC.
【００３８】次のステップ２８では、学習マップで基本
燃料噴射量Ｔｐにより区切られる１６格子上での該当位
置を示す〔Ｉ〕に前記推定学習カウンタＺＺを加算した
値を、基本燃料噴射量Ｔｐで区切られる格子上で一度に
学習させる格子範囲の最大位置を示すｐｍａｘ にセッ
トすると共に、前記格子位置〔Ｉ〕から前記推定学習カ
ウンタＺＺを減算した値を、基本燃料噴射量Ｔｐで区切
られる格子上で一度に学習させる格子範囲の最小位置を
示すｐｍｉｎにセットする。即ち、該当格子位置〔Ｉ〕
を含むｐｍｉｎ 〜ｐｍａｘ を、基本燃料噴射量Ｔｐ
で区切られる格子上で今回学習させる範囲とするもので
ある。In the next step 28, the value obtained by adding the estimated learning counter ZZ to [I] indicating the corresponding position on the 16 grids divided by the basic fuel injection amount Tp in the learning map is calculated as the basic fuel injection amount Tp. Set pmax indicating the maximum position of the grid range to be learned at once on the grid divided, and set the value obtained by subtracting the estimated learning counter ZZ from the grid position [I] on the grid divided by the basic fuel injection amount Tp. Set pmin to indicate the minimum position of the grid range to be learned at once. That is, the corresponding grid position [I]
pmin to pmax including basic fuel injection amount Tp
The range to be learned this time is on a grid divided by .
【００３９】ステップ２９〜ステップ３２では、前記ス
テップ２８で設定したｐｍｉｎ 及びｐｍａｘ が、φ
〜１５の設定範囲を越えて設定されたときに、許容最小
値であるゼロ又は許容最大値である１５に規制する処理
を行う。同様に、ステップ３３では、機関回転速度Ｎに
より区分される格子上での学習領域をｑｍｉｎ （←Ｋ
−ＺＺ）〜ｑｍａｘ （←Ｋ＋ＺＺ）として設定し、ス
テップ３４〜ステップ３７では前記学習領域設定ｑｍｉ
ｎ 〜ｑｍａｘ を、φ〜１５の設定範囲内に規制する
処理を行う。In steps 29 to 32, pmin and pmax set in step 28 are changed to φ
When the setting exceeds the setting range of ~15, a process is performed to limit the value to zero, which is the minimum allowable value, or to 15, which is the maximum allowable value. Similarly, in step 33, the learning area on the grid divided by the engine rotational speed N is set to qmin (←K
−ZZ) to qmax (←K+ZZ), and in steps 34 to 37, the learning area setting qmi
A process is performed to restrict n to qmax within a set range of φ to 15.
【００４０】そして、次のステップ３８では、上記のよ
うにして設定された学習範囲の中で、格子番号の一番小
さい領域を示すｐｍｉｎ ，ｑｍｉｎ をそれぞれカウ
ンタｉ，ｊにセットする。ステップ３９では、前記ｐｍ
ｉｎ が初期設定されたカウンタｉが最大値ｐｍａｘ
以下であるか否かを判別し、ｐｍａｘ 以下であるとき
には、ステップ４０へ進む。In the next step 38, pmin and qmin indicating the area with the smallest grid number within the learning range set as described above are set in counters i and j, respectively. In step 39, the pm
The counter i for which in is initially set is the maximum value pmax
It is determined whether or not it is less than or equal to pmax, and if it is less than or equal to pmax, the process proceeds to step 40.
【００４１】ステップ４０では、前記ｑｍｉｎ が初期
設定されたカウンタｊが最大値ｑｍａｘ 以下であるか
否かを判別し、ここで、カウンタｊがｑｍａｘ 以下で
あると判別されたときには、ステップ４１へ進み、〔ｉ
〕〔ｊ〕で指示される領域位置に対応する学習補正係数
ＫＢＬＲＣ を、前記ステップ２７で該当領域に対応す
る値として更新設定された学習補正係数ＫＢＬＲＣ に
書き換える。[0041] In step 40, it is determined whether the counter j whose qmin is initialized is less than or equal to the maximum value qmax. If it is determined that the counter j is less than or equal to qmax, the process proceeds to step 41. , [i
] The learning correction coefficient KBLRC corresponding to the area position indicated by [j] is rewritten to the learning correction coefficient KBLRC updated and set as the value corresponding to the corresponding area in step 27.
【００４２】次のステップ４２では、カウンタｊを１ア
ップさせて、再びステップ４０へ戻り、カウンタｊがｑ
ｍａｘ を越えるまでは、ステップ４１へ進ませて〔ｉ
〕〔ｊ〕で指示される領域位置に同じ学習補正係数ＫＢ
ＬＲＣ を設定させる。ステップ４０でカウンタｊがｑ
ｍａｘを越えると判別されたときには、ステップ４３へ
進み、カウンタｉを１アップさせると共に、カウンタｊ
をｑｍｉｎ にリセットし、ステップ３９へ進む。そし
て、ステップ３９でカウンタｉがｐｍａｘ を越えたと
判別されるまでは、カウンタｉを固定した状態でカウン
タｊをｑｍｉｎ からｑｍａｘ まで変化させ、〔ｉ〕
〔ｊ〕で指示される領域位置に同じ学習補正係数ＫＢＬ
ＲＣ を設定させる処理を繰り返す。In the next step 42, the counter j is incremented by 1, and the process returns to step 40, where the counter j becomes q.
Until max is exceeded, proceed to step 41 [i
] The same learning correction coefficient KB is applied to the area position indicated by [j]
Let LRC be set. At step 40, counter j becomes q.
When it is determined that the value exceeds max, the process proceeds to step 43, where the counter i is incremented by 1, and the counter j is incremented by 1.
is reset to qmin, and the process proceeds to step 39. Then, until it is determined in step 39 that counter i has exceeded pmax, counter j is changed from qmin to qmax with counter i fixed, and [i]
The same learning correction coefficient KBL is applied to the area position indicated by [j]
Repeat the process to set RC.
【００４３】かかる学習により、学習マップ上の２５６
領域中で、該当運転領域〔Ｉ〕〔Ｋ〕を含む〔ｐｍｉ
ｎ 〕〔ｑｍｉｎ 〕〜〔ｐｍａｘ 〕〔ｑｍａｘ 〕
の各運転領域（該当運転領域の運転条件に近い他の運転
領域）に、該当運転領域〔Ｉ〕〔Ｋ〕に対応するものと
同じ学習補正係数ＫＢＬＲＣ を設定するものであり、
前記推定学習カウンタＺＺが比較的大きく設定される学
習済領域数が少ない状態では、該当運転領域〔Ｉ〕〔Ｋ
〕を含む広範囲に同じ学習補正係数ＫＢＬＲＣ が適用
されることになって良好な学習収束性が得られ、学習済
領域が増えて前記推定学習カウンタＺＺが減少するに従
って学習範囲が狭められ、最終的には学習マップ上で区
切られた２５６ 領域をそれぞれ個別に学習することに
なる。[0043] Through such learning, 256 on the learning map
In the area, [pmi] includes the relevant operation area [I] [K]
n ] [qmin] ~ [pmax] [qmax]
The same learning correction coefficient KBLRC as that corresponding to the corresponding operating region [I] [K] is set for each operating region (another operating region close to the operating conditions of the corresponding operating region).
In a state where the estimated learning counter ZZ is set relatively large and the number of learned regions is small, the corresponding driving region [I] [K
] The same learning correction coefficient KBLRC is applied to a wide range including In this case, each of the 256 areas divided on the learning map will be studied individually.
【００４４】従って、運転領域を細かく区分した学習マ
ップのみを備えた構成で、学習の収束性と学習精度とを
両立させることができ、学習補正係数ＫＢＬＲＣ を記
憶させる単位運転領域の広さを異ならせた複数の学習マ
ップを備えて学習させる場合に比べ、メモリ容量を節約
できる。図６のフローチャートに示すプログラムは、運
転領域を２５６ 領域に区分した学習マップ上での学習
済領域を、各運転領域別に設定記憶される学習済フラグ
Ｆｌａｇ に基づいて検出し、かかる学習済領域数を計
数するためのプログラムであり、バックグラウンドジョ
ブ（ＢＧＪ）として実行される。Therefore, it is possible to achieve both learning convergence and learning accuracy with a configuration that includes only a learning map that finely divides the driving area, and it is possible to achieve both learning convergence and learning accuracy by changing the width of the unit driving area in which the learning correction coefficient KBLRC is stored. Memory capacity can be saved compared to when training is performed using multiple learning maps. The program shown in the flowchart of FIG. 6 detects learned areas on a learning map that divides the driving area into 256 areas based on a learned flag set and stored for each driving area, and calculates the number of learned areas. This is a program for counting the number of digits, and is executed as a background job (BGJ).
【００４５】まず、ステップ５１では、２５６ 領域そ
れぞれを個別に指示するためのカウンタｉ，ｊをそれぞ
れゼロリセットすると共に、学習済の領域数を計数する
ためのカウンタＺをゼロリセットする。ステップ５２〜
５８では、カウンタｉを固定させておいて、カウンタｊ
をゼロから１５までカウントアップしていき、〔ｉ〕〔
ｊ〕で指示される領域に対応する学習済フラグＦｌａｇ
が１であるときにはカウンタＺを１アップさせる処理
を繰り返し行うことで、２５６ 領域の全てで学習済フ
ラグＦｌａｇ を判別し、学習済である（学習済フラグ
Ｆｌａｇ に１がセットされている）運転領域の数がカ
ウンタＺにセットされるようにする。First, in step 51, counters i and j for individually indicating each of the 256 areas are reset to zero, and a counter Z for counting the number of learned areas is reset to zero. Step 52~
58, counter i is fixed and counter j
Count up from zero to 15, [i]
Learned flag Flag corresponding to the area indicated by j]
When is 1, by repeating the process of incrementing the counter Z by 1, the learned flag Flag is determined in all 256 areas, and the operating area that has been learned (the learned flag Flag is set to 1) is determined. is set in counter Z.
【００４６】そして、ステップ５９では、カウンタＺの
値を学習済領域数Ｓｔａｔｕｓ にセットし、この学習
済領域数Ｓｔａｔｕｓ に基づいて図４のフローチャー
トにおけるステップ２６で推定学習カウンタＺＺが設定
されるようにする。次のステップ６０では、図３のフロ
ーチャートにおいて補正係数ＬＭＤの比例制御毎に更新
設定される「ストレス」が所定レベルを越えているか否
かを判別する。前記「ストレス」は、学習マップの全て
の領域が学習済であるのに、ベース空燃比の変化によっ
て学習結果が不適正となって、該当運転領域の切り換え
時に、要求補正レベルと学習されている学習補正係数Ｋ
ＢＬＲＣ とのレベル差を補償すべく補正係数ＬＭＤを
大きく変化させる必要が生じると、該当運転領域の切り
換え毎に増大設定されることになる。従って、前記「ス
トレス」が所定レベルを越える場合には、学習済の結果
が実際のベース空燃比に対応していないものと予測され
る。Then, in step 59, the value of the counter Z is set to the learned area number Status, and the estimated learning counter ZZ is set in step 26 in the flowchart of FIG. 4 based on this learned area number Status. do. In the next step 60, it is determined whether "stress", which is updated and set every time the correction coefficient LMD is proportionally controlled in the flowchart of FIG. 3, exceeds a predetermined level. The above-mentioned "stress" is that even though all areas of the learning map have been learned, the learning result becomes inappropriate due to a change in the base air-fuel ratio, and the required correction level is learned when switching to the corresponding operating area. Learning correction coefficient K
If it becomes necessary to greatly change the correction coefficient LMD to compensate for the level difference with BLRC, the correction coefficient LMD will be set to be increased each time the corresponding operating region is switched. Therefore, if the "stress" exceeds a predetermined level, it is predicted that the learned result does not correspond to the actual base air-fuel ratio.
【００４７】そこで、ステップ６０で前記「ストレス」
が所定レベルを越えると判別されたときには、ステップ
６１で前記学習済領域数Ｓｔａｔｕｓにゼロをセットす
ることによって、学習マップ上で該当領域と共に学習補
正係数ＫＢＬＲＣ が書き換えられる領域数を最大とす
る一方、学習済であるとして１がセットされている各運
転領域の学習済フラグＦｌａｇ 〔φ〕〔φ〕〜〔１５
〕〔１５〕を全てゼロリセットし、該当運転領域を含む
広い範囲を一度に学習させる学習から再度行わせる。[0047] Therefore, in step 60, the above-mentioned "stress"
When it is determined that the learning correction coefficient KBLRC exceeds a predetermined level, the learned area number Status is set to zero in step 61, thereby maximizing the number of areas where the learning correction coefficient KBLRC is rewritten together with the corresponding area on the learning map, Learned flag Flag [φ] [φ] to [15] for each driving region that is set to 1 indicating that it has been learned
] [15] All are reset to zero, and the learning is started again by learning a wide range including the relevant driving range at once.
【００４８】従って、ベース空燃比が変化して学習結果
が不適正となったときに、広い運転領域を単位として再
学習が速やかに進行するから、ベース空燃比の急変時に
おける空燃比制御性の悪化を最小限に抑止でき、学習が
進行して学習済領域数が増大していくと、学習領域が狭
くなって（該当領域と共に学習される領域数が少なくな
って）、運転条件毎の補正要求に答えた補正が再度行え
るようになる。このため、基本的に細かく区分された運
転領域別に空燃比学習を行わせつつ、ベース空燃比の急
変時には速やかに学習を収束させることができる。[0048] Therefore, when the base air-fuel ratio changes and the learning result becomes inappropriate, re-learning proceeds quickly in a wide operating range, which improves the air-fuel ratio controllability when the base air-fuel ratio suddenly changes. The deterioration can be suppressed to a minimum, and as learning progresses and the number of learned areas increases, the learning area becomes narrower (the number of areas learned along with the corresponding area decreases), and corrections for each driving condition are made. Corrections in response to requests can be made again. Therefore, while air-fuel ratio learning is basically performed for each finely divided operating region, the learning can be quickly converged when the base air-fuel ratio suddenly changes.
【００４９】また、ステップ６２では、前記「ストレス
」をゼロリセットし、上記のようにして行われる再学習
が全ての領域で収束してから、学習結果の不適正さが前
記「ストレス」に積算されるようにする。図７のフロー
チャートに示すプログラムは燃料噴射量の設定プログラ
ムであり、所定微小時間（例えば１０ｍｓ）毎に実行さ
れる。Further, in step 62, the "stress" is reset to zero, and after the relearning performed as described above has converged in all areas, the inappropriateness of the learning result is accumulated in the "stress". to be done. The program shown in the flowchart of FIG. 7 is a fuel injection amount setting program, and is executed at predetermined minute intervals (for example, 10 ms).
【００５０】まず、ステップ７１では、エアフローメー
タ１３によって検出された吸入空気流量Ｑやクランク角
センサ１４からの信号に基づき演算された機関回転速度
Ｎなどを読み込む。ステップ７２では、吸入空気流量Ｑ
と機関回転速度Ｎとに基づいて基本燃料噴射量Ｔｐ（←
Ｑ／Ｎ×Ｋ；Ｋは定数）を演算する。First, in step 71, the intake air flow rate Q detected by the air flow meter 13, the engine rotational speed N calculated based on the signal from the crank angle sensor 14, etc. are read. In step 72, the intake air flow rate Q
The basic fuel injection amount Tp (←
Q/N×K; K is a constant) is calculated.
【００５１】ステップ７３では、図３のフローチャート
に比例積分制御される空燃比フィードバック補正係数Ｌ
ＭＤを読み込む。ステップ７４では、水温センサ１５で
検出される冷却水温度に基づく基本補正係数や過渡補正
係数などを含んだ各種補正係数を設定する。ステップ７
５では、バッテリ電圧の変化による燃料噴射弁６の有効
開弁時間の変化を補正するための電圧補正分Ｔｓを設定
する。In step 73, the air-fuel ratio feedback correction coefficient L, which is subjected to proportional-integral control according to the flowchart of FIG.
Load the MD. In step 74, various correction coefficients including a basic correction coefficient and a transient correction coefficient based on the cooling water temperature detected by the water temperature sensor 15 are set. Step 7
5, a voltage correction amount Ts is set for correcting a change in the effective valve opening time of the fuel injection valve 6 due to a change in battery voltage.
【００５２】また、ステップ７６では、前記ステップ７
２で演算された基本燃料噴射量Ｔｐと機関回転速度Ｎと
から、学習マップ上の該当運転領域を特定し、かかる該
当運転領域に対応して記憶されている学習補正係数ＫＢ
ＬＲＣを読み出す。そして、ステップ７７では、基本燃
料噴射量Ｔｐを、空燃比フィードバック補正係数ＬＭＤ
，各種補正係数ＣＯＥＦ，電圧補正分Ｔｓ，学習補正係
数ＫＢＬＲＣ によって補正し、最終的な燃料噴射量Ｔ
ｉ（←２Ｔｐ×ＫＢＬＲＣ ×ＬＭＤ×ＣＯＥＦ＋Ｔｓ
）を演算する。[0052] Also, in step 76, the step 7
From the basic fuel injection amount Tp and engine rotational speed N calculated in step 2, the corresponding operating region on the learning map is specified, and the learning correction coefficient KB stored corresponding to the corresponding operating region is determined.
Read LRC. Then, in step 77, the basic fuel injection amount Tp is adjusted to the air-fuel ratio feedback correction coefficient LMD.
, various correction coefficients COEF, voltage correction Ts, learning correction coefficient KBLRC, and the final fuel injection amount T
i(←2Tp×KBLRC×LMD×COEF+Ts
) is calculated.
【００５３】コントロールユニット１２は、機関回転に
同期した所定の噴射タイミングになると、上記ステップ
７７で最新に設定された燃料噴射量Ｔｉに相当する駆動
パルス信号を燃料噴射弁６に出力して、機関への燃料噴
射供給を行わせる。尚、本実施例では、基本燃料噴射量
Ｔｐと機関回転速度Ｎとに基づいて運転領域を２５６
領域に区分し、これらの運転領域別に学習補正係数ＫＢ
ＬＲＣ を学習させるよう構成したが、区分数や運転条
件を上記に限定するものでないことは明らかである。ま
た、基本燃料噴射量Ｔｐの設定は、吸入空気流量Ｑと機
関回転速度Ｎとに基づくものに限定されず、例えば吸入
負圧と機関回転速度Ｎとから基本燃料噴射量Ｔｐが設定
されるものであっても良い。When a predetermined injection timing synchronized with the engine rotation is reached, the control unit 12 outputs a drive pulse signal corresponding to the fuel injection amount Ti most recently set in step 77 to the fuel injection valve 6, thereby starting the engine. to supply fuel by injection. In this embodiment, the operating range is set to 256 based on the basic fuel injection amount Tp and the engine rotational speed N.
The learning correction coefficient KB is divided into operating regions.
Although the system is configured to learn LRC, it is clear that the number of classifications and operating conditions are not limited to the above. Further, the setting of the basic fuel injection amount Tp is not limited to one based on the intake air flow rate Q and the engine rotation speed N, but, for example, the basic fuel injection amount Tp can be set based on the intake negative pressure and the engine rotation speed N. It may be.
【００５４】[0054]
【発明の効果】以上説明したように本発明によると、学
習初期の学習収束性を確保しつつ、運転条件の違いによ
る補正要求の違いに精度良く対応した空燃比学習を、必
要とされるメモリ容量を節約して実現できるという効果
がある。また、運転条件に細かく対応した空燃比学習を
行わせつつ、ベース空燃比の変化により学習結果が不適
正になったときに、速やかに再学習を収束させることが
できるという効果がある。As explained above, according to the present invention, air-fuel ratio learning that accurately responds to differences in correction requests due to differences in operating conditions while ensuring learning convergence at the initial stage of learning can be performed using the required memory. This has the effect of saving capacity. Another advantage is that while air-fuel ratio learning is performed in detail in response to operating conditions, re-learning can be quickly converged when the learning result becomes inappropriate due to a change in the base air-fuel ratio.
【図１】本発明の構成を示すブロック図。FIG. 1 is a block diagram showing the configuration of the present invention.
【図２】本発明の一実施例を示すシステム概略図。FIG. 2 is a system schematic diagram showing an embodiment of the present invention.
【図３】空燃比フィードバック制御を示すフローチャー
ト。FIG. 3 is a flowchart showing air-fuel ratio feedback control.
【図４】空燃比学習制御を示すフローチャート。FIG. 4 is a flowchart showing air-fuel ratio learning control.
【図５】空燃比学習制御を示すフローチャート。FIG. 5 is a flowchart showing air-fuel ratio learning control.
【図６】学習済領域数の検出制御を示すフローチャート
。FIG. 6 is a flowchart showing control for detecting the number of learned regions.
【図７】燃料噴射量の設定制御を示すフローチャート。FIG. 7 is a flowchart showing fuel injection amount setting control.
１ 機関 ６ 燃料噴射弁 １２ コントロールユニット １３ エアフローメータ １４ クランク角センサ １５ 水温センサ １６ 酸素センサ 1. Institution 6 Fuel injection valve 12 Control unit 13 Air flow meter 14 Crank angle sensor 15 Water temperature sensor 16 Oxygen sensor
Claims (2)
ラメータを少なくとも含む機関運転条件を検出する運転
条件検出手段と、該運転条件検出手段で検出された機関
運転条件に基づいて基本燃料供給量を設定する基本燃料
供給量設定手段と、機関吸入混合気の空燃比を検出する
空燃比検出手段と、該空燃比検出手段で検出された空燃
比と目標空燃比とを比較して実際の空燃比を前記目標空
燃比に近づけるように前記基本燃料供給量を補正するた
めの空燃比フィードバック補正値を設定する空燃比フィ
ードバック補正値設定手段と、機関運転条件に基づき複
数に区分された運転領域毎に前記基本燃料供給量を補正
するための空燃比学習補正値を書き換え可能に記憶する
学習補正値記憶手段と、前記空燃比フィードバック補正
値の目標収束値からの偏差を学習し、前記学習補正値記
憶手段において該当領運転領域に対応して記憶されてい
る前記空燃比学習補正値を前記偏差を減少させる方向に
修正して書き換える空燃比学習手段と、前記空燃比フィ
ードバック補正値が目標収束値に略一致するときに、そ
のときの前記学習補正値記憶手段上での該当運転領域を
学習済領域として判別し、かかる判別結果を前記学習補
正値記憶手段の各運転領域別に記憶する学習済領域記憶
手段と、前記空燃比学習手段により書き換えられた該当
運転領域の空燃比学習補正値を、前記該当運転領域に対
して運転条件の近い別の運転領域に対応する空燃比学習
補正値として学習補正値記憶手段上の該当運転領域以外
の空燃比学習補正値を書き換える推定学習手段と、前記
学習済領域記憶手段に記憶される学習済領域数の増大に
応じて前記推定学習手段で空燃比学習補正値が該当運転
領域と共に書き換えられる運転領域の数を減少させる学
習済領域数による推定学習制御手段と、前記基本燃料供
給量，空燃比フィードバック補正値及び学習補正値記憶
手段において該当運転領域に対応して記憶されている空
燃比学習補正値に基づいて最終的な燃料供給量を設定す
る燃料供給量設定手段と、該燃料供給量設定手段で設定
された燃料供給量に基づいて燃料供給手段を駆動制御す
る燃料供給制御手段と、を含んで構成されたことを特徴
とする内燃機関の空燃比学習制御装置。1. Operating condition detection means for detecting engine operating conditions including at least operating parameters related to the amount of air taken into the engine; and basic fuel supply based on the engine operating conditions detected by the operating condition detection means. A basic fuel supply amount setting means for setting the amount of fuel supply, an air-fuel ratio detection means for detecting the air-fuel ratio of the engine intake air-fuel mixture, and an air-fuel ratio detected by the air-fuel ratio detection means and a target air-fuel ratio are compared to determine the actual air-fuel ratio. an air-fuel ratio feedback correction value setting means for setting an air-fuel ratio feedback correction value for correcting the basic fuel supply amount so as to bring the air-fuel ratio closer to the target air-fuel ratio; and an operating region divided into a plurality of regions based on engine operating conditions. a learning correction value storage means for rewritably storing an air-fuel ratio learning correction value for correcting the basic fuel supply amount at each time, and learning a deviation of the air-fuel ratio feedback correction value from a target convergence value, an air-fuel ratio learning means for correcting and rewriting the air-fuel ratio learning correction value stored in the value storage means corresponding to the relevant operating region in a direction that reduces the deviation; and the air-fuel ratio feedback correction value is a target convergence value. a learned area for determining the relevant driving area on the learning correction value storage means at that time as a learned area when substantially matching the learning correction value storage means, and storing the determination result for each driving area in the learning correction value storage means; Learning correction is performed by storing the air-fuel ratio learning correction value of the corresponding operating region rewritten by the storage means and the air-fuel ratio learning means as an air-fuel ratio learning correction value corresponding to another operating region whose operating conditions are close to the corresponding operating region. an estimation learning means for rewriting the air-fuel ratio learning correction value in a value storage means other than the relevant operating region; and an air-fuel ratio learning correction by the estimation learning means according to an increase in the number of learned regions stored in the learned region storage means. Estimation learning control means based on the number of learned regions that reduces the number of operating regions whose values are rewritten together with the corresponding operating region; and the basic fuel supply amount, air-fuel ratio feedback correction value and learning correction value storage means that correspond to the corresponding operating region. a fuel supply amount setting means for setting a final fuel supply amount based on an air-fuel ratio learning correction value stored in the memory; and a fuel supply amount setting means for driving the fuel supply means based on the fuel supply amount set by the fuel supply amount setting means. An air-fuel ratio learning control device for an internal combustion engine, comprising a fuel supply control means for controlling the air-fuel ratio.
ラメータを少なくとも含む機関運転条件を検出する運転
条件検出手段と、該運転条件検出手段で検出された機関
運転条件に基づいて基本燃料供給量を設定する基本燃料
供給量設定手段と、機関吸入混合気の空燃比を検出する
空燃比検出手段と、該空燃比検出手段で検出された空燃
比と目標空燃比とを比較して実際の空燃比を前記目標空
燃比に近づけるように前記基本燃料供給量を補正するた
めの空燃比フィードバック補正値を設定する空燃比フィ
ードバック補正値設定手段と、機関運転条件に基づき複
数に区分された運転領域毎に前記基本燃料供給量を補正
するための空燃比学習補正値を書き換え可能に記憶する
学習補正値記憶手段と、前記空燃比フィードバック補正
値の目標収束値からの偏差を学習し、前記学習補正値記
憶手段において該当領運転領域に対応して記憶されてい
る前記空燃比学習補正値を前記偏差を減少させる方向に
修正して書き換える空燃比学習手段と、該空燃比学習手
段により書き換えられた該当運転領域の空燃比学習補正
値を、前記該当運転領域に対して運転条件の近い別の運
転領域に対応する空燃比学習補正値として学習補正値記
憶手段上の該当運転領域以外の空燃比学習補正値を書き
換える推定学習手段と、前記学習補正値記憶手段上にお
いて該当運転領域が切り換わったときの前記空燃比フィ
ードバック補正値の目標収束値に対する偏差に基づいて
空燃比学習結果の適正を判断する適正判断手段と、該適
正判断手段で学習結果が不適正であることが判断された
ときに、前記推定学習手段により該当運転領域と共に空
燃比学習補正値が書き換えられる運転領域の数を最大数
とし、その後学習の進行と共に前記運転領域の数を減少
させる適正判断による推定学習制御手段と、前記基本燃
料供給量，空燃比フィードバック補正値及び学習補正値
記憶手段において該当運転領域に対応して記憶されてい
る空燃比学習補正値に基づいて最終的な燃料供給量を設
定する燃料供給量設定手段と、該燃料供給量設定手段で
設定された燃料供給量に基づいて燃料供給手段を駆動制
御する燃料供給制御手段と、を含んで構成されたことを
特徴とする内燃機関の空燃比学習制御装置。2. Operating condition detection means for detecting engine operating conditions including at least operating parameters related to the amount of air taken into the engine; and basic fuel supply based on the engine operating conditions detected by the operating condition detection means. A basic fuel supply amount setting means for setting the amount of fuel supply, an air-fuel ratio detection means for detecting the air-fuel ratio of the engine intake air-fuel mixture, and an air-fuel ratio detected by the air-fuel ratio detection means and a target air-fuel ratio are compared to determine the actual air-fuel ratio. an air-fuel ratio feedback correction value setting means for setting an air-fuel ratio feedback correction value for correcting the basic fuel supply amount so as to bring the air-fuel ratio closer to the target air-fuel ratio; and an operating region divided into a plurality of regions based on engine operating conditions. a learning correction value storage means for rewritably storing an air-fuel ratio learning correction value for correcting the basic fuel supply amount at each time, and learning a deviation of the air-fuel ratio feedback correction value from a target convergence value, air-fuel ratio learning means for correcting and rewriting the air-fuel ratio learning correction value stored in the value storage means corresponding to the relevant operating region in a direction that reduces the deviation; The air-fuel ratio learning correction value for the operating region is used as the air-fuel ratio learning correction value corresponding to another operating region whose operating conditions are close to the corresponding operating region, and the air-fuel ratio learning correction value for the operating region other than the corresponding operating region is stored in the learning correction value storage means. Estimation learning means for rewriting the value; and appropriateness for determining the appropriateness of the air-fuel ratio learning result based on the deviation of the air-fuel ratio feedback correction value from the target convergence value when the corresponding operating region is switched on the learning correction value storage means. determining means, and when the learning result is determined to be inappropriate by the appropriateness determining means, the maximum number of operating regions for which the air-fuel ratio learning correction value is rewritten together with the corresponding operating region by the estimating learning means; Thereafter, as the learning progresses, the number of operating regions is reduced by an estimated learning control means based on appropriate judgment, and the basic fuel supply amount, air-fuel ratio feedback correction value, and learning correction value storage means are stored in correspondence with the corresponding operating region. a fuel supply amount setting means for setting the final fuel supply amount based on the air-fuel ratio learning correction value, and a fuel supply for driving and controlling the fuel supply means based on the fuel supply amount set by the fuel supply amount setting means. An air-fuel ratio learning control device for an internal combustion engine, comprising: a control means.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8542191A JP2631579B2 (en) | 1991-04-17 | 1991-04-17 | Air-fuel ratio learning control device for internal combustion engine |
| US07/869,341 US5297046A (en) | 1991-04-17 | 1992-04-16 | System and method for learning and controlling air/fuel mixture ratio for internal combustion engine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8542191A JP2631579B2 (en) | 1991-04-17 | 1991-04-17 | Air-fuel ratio learning control device for internal combustion engine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04318245A true JPH04318245A (en) | 1992-11-09 |
| JP2631579B2 JP2631579B2 (en) | 1997-07-16 |
Family
ID=13858357
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8542191A Expired - Fee Related JP2631579B2 (en) | 1991-04-17 | 1991-04-17 | Air-fuel ratio learning control device for internal combustion engine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2631579B2 (en) |
-
1991
- 1991-04-17 JP JP8542191A patent/JP2631579B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JP2631579B2 (en) | 1997-07-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPH0826805B2 (en) | Air-fuel ratio learning controller for internal combustion engine | |
| JP2742431B2 (en) | Engine air-fuel ratio control device | |
| JPH03179147A (en) | Air-fuel learning controller for internal combustion engine | |
| JPH0689690B2 (en) | Air-fuel ratio learning controller for internal combustion engine | |
| JPH04318245A (en) | Air-fuel ratio study control device for internal combustion engine | |
| JP2715208B2 (en) | Air-fuel ratio learning control device for internal combustion engine | |
| JP2582571B2 (en) | Learning control device for air-fuel ratio of internal combustion engine | |
| JPH04321741A (en) | Air-fuel ratio learning control device for internal combustion engine | |
| JPH0979072A (en) | Air-fuel ratio learning control device for internal combustion engine | |
| JP2640566B2 (en) | Air-fuel ratio learning control device for internal combustion engine | |
| JPH04318246A (en) | Air-fuel ratio study control device for internal combustion engine | |
| JPH04241756A (en) | Air-fuel ratio study control device for internal combustion engine | |
| JP2627825B2 (en) | Air-fuel ratio learning control device for internal combustion engine | |
| JP2940916B2 (en) | Air-fuel ratio control device for internal combustion engine | |
| JP2631580B2 (en) | Air-fuel ratio learning control device for internal combustion engine | |
| JPH0450449Y2 (en) | ||
| JPH0686831B2 (en) | Air-fuel ratio learning controller for internal combustion engine | |
| JPH04237847A (en) | Air-fuel ratio learning controller for internal combustion engine | |
| JPH01106938A (en) | Control device for learning of internal combustion engine | |
| JPS63297752A (en) | Learning controller for air-fuel ratio for internal combustion engine | |
| JPH04318247A (en) | Air-fuel ratio study control device for internal combustion engine | |
| JPH05156988A (en) | Air fuel ratio control device of internal combustion engine | |
| JPS62165555A (en) | Air-fuel ratio control method for internal combustion engine | |
| JPH04255545A (en) | Air-fuel ratio study control device for internal combustion engine | |
| JPH04255544A (en) | Air-fuel ratio study control device for internal combustion engine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| S111 | Request for change of ownership or part of ownership |
Free format text: JAPANESE INTERMEDIATE CODE: R313111 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| LAPS | Cancellation because of no payment of annual fees |