JPH059620B2 - - Google Patents
Info
- Publication number
- JPH059620B2 JPH059620B2 JP57027845A JP2784582A JPH059620B2 JP H059620 B2 JPH059620 B2 JP H059620B2 JP 57027845 A JP57027845 A JP 57027845A JP 2784582 A JP2784582 A JP 2784582A JP H059620 B2 JPH059620 B2 JP H059620B2
- Authority
- JP
- Japan
- Prior art keywords
- increase
- engine
- intake pipe
- pipe pressure
- correction coefficient
- 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.)
- Expired - Lifetime
Links
- 239000000446 fuel Substances 0.000 claims description 60
- 238000002347 injection Methods 0.000 claims description 43
- 239000007924 injection Substances 0.000 claims description 43
- 238000012937 correction Methods 0.000 claims description 36
- 230000001133 acceleration Effects 0.000 claims description 30
- 238000013016 damping Methods 0.000 claims description 16
- 238000002485 combustion reaction Methods 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 11
- 230000001052 transient effect Effects 0.000 claims description 6
- 230000002238 attenuated effect Effects 0.000 claims description 3
- 230000004044 response Effects 0.000 description 10
- 239000007789 gas Substances 0.000 description 9
- 239000000498 cooling water Substances 0.000 description 8
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 7
- 229910052760 oxygen Inorganic materials 0.000 description 7
- 239000001301 oxygen Substances 0.000 description 7
- 230000000694 effects Effects 0.000 description 5
- 238000000746 purification Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000000994 depressogenic effect Effects 0.000 description 3
- 239000002826 coolant Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000004043 responsiveness Effects 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
- 230000004580 weight loss Effects 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/04—Introducing corrections for particular operating conditions
- F02D41/06—Introducing corrections for particular operating conditions for engine starting or warming up
- F02D41/068—Introducing corrections for particular operating conditions for engine starting or warming up for warming-up
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
Description
本発明は、内燃機関の電子制御燃料噴射方法に
係り、特に、電子制御燃料噴射装置を備えた自動
車用内燃機関に用るのに好適な、エンジンの吸気
管圧力とエンジン回転数に応じて基本噴射量を求
めると共に、過渡時は、エンジン運転状態に応じ
て算出される補正係数により前記基本噴射量を補
正することによつて燃料噴射量を決定するように
した内燃機関の電子制御燃料噴射方法の改良に関
する。
The present invention relates to an electronically controlled fuel injection method for an internal combustion engine, and is particularly suitable for use in an automobile internal combustion engine equipped with an electronically controlled fuel injection device. An electronically controlled fuel injection method for an internal combustion engine, which determines the fuel injection amount by determining the injection amount and, during transient periods, correcting the basic injection amount using a correction coefficient calculated according to the engine operating state. Regarding improvements.
自動車用エンジン等の内燃機関の燃焼室に所定
空燃比の混合気を供給する方法の一つに、電子制
御燃料噴射装置を用いるものがある。
これは、エンジン内に燃料を噴射するためのイ
ンジエクタを、例えば、エンジンの吸気マニホー
ルドあるいはスロツトルボデイに、エンジン気筒
数個あるいは１個配設し、該インジエクタの開弁
時間をエンジンの運転状態に応じて制御すること
により、所定の空燃比の混合気がエンシン燃焼室
に供給されるようにするものである。
この電子制御燃料噴射装置には、大別して、エ
ンジンの吸入空気量とエンジン回転数に応じて基
本噴射量を求めるようにした、いわゆる吸入空気
量感知式の電子制御燃料噴射装置と、エンジンの
吸気管圧力とエンジン回転数に応じて基本噴射量
を求めるようにした、いわゆる吸気管圧力感知式
の電子制御燃料噴射装置がある。
このうち前者は、空燃比を精密に制御すること
が可能であり、排気ガス浄化対策が施された自動
車用エンジンに広く用いられるようになつてい
る。
この吸入空気感知式の電子制御燃料噴射装置に
おいては、加速時のドライバビリテイ及び排気ガ
ス浄化性能を確保するべく、加速時に補正係数を
増大させ、次いで、所定の減衰速度で減衰させる
ことによつて加速増量を行うようにされている。
この加速増量においては、エンジン要求特性に
合わせて、加速増量の減衰速度を、減衰途中で低
速に切換えるようになされているが、従来は、前
記切換えを加速終了後の所定時間経過時に行うよ
うにしていたため、特に、エンジン暖機中の加速
性能を向上するべく、前記補正係数を更に所定の
補正倍率で増大した場合に、減衰速度の低速への
切換えが早く行われ過ぎて、切換え後に過増量と
なつて、空燃比がオーバーリツチとなることがあ
つた。
一方、後者の吸気管圧力感知式の電子制御燃料
噴射装置は、前者に比べて安価に構成できるとい
う利点を有する。
2. Description of the Related Art One of the methods for supplying an air-fuel mixture at a predetermined air-fuel ratio to the combustion chamber of an internal combustion engine such as an automobile engine uses an electronically controlled fuel injection device. In this method, an injector for injecting fuel into the engine is installed in the intake manifold or throttle body of the engine, for example, in several engine cylinders or one engine cylinder, and the valve opening time of the injector is adjusted depending on the operating state of the engine. By controlling this, an air-fuel mixture with a predetermined air-fuel ratio is supplied to the engine combustion chamber. These electronically controlled fuel injection devices can be roughly divided into so-called intake air amount sensing type electronically controlled fuel injection devices that calculate the basic injection amount according to the engine's intake air amount and engine speed, and There is a so-called intake pipe pressure sensing type electronically controlled fuel injection system that determines a basic injection amount according to pipe pressure and engine speed. Among these, the former allows for precise control of the air-fuel ratio, and has come to be widely used in automobile engines equipped with exhaust gas purification measures. In this intake air sensing type electronically controlled fuel injection system, in order to ensure drivability and exhaust gas purification performance during acceleration, the correction coefficient is increased during acceleration, and then damped at a predetermined damping speed. Accelerated increase in dosage is performed. In this acceleration increase, the attenuation speed of the acceleration increase is switched to a low speed in the middle of decay in accordance with the required engine characteristics, but conventionally, the switching was performed after a predetermined period of time had elapsed after the end of acceleration. In particular, when the correction coefficient is further increased by a predetermined correction factor in order to improve acceleration performance during engine warm-up, the damping speed is switched too quickly to a low speed, resulting in an excessive increase in the amount after switching. As a result, the air-fuel ratio sometimes became overrich. On the other hand, the latter electronically controlled fuel injection system that detects intake pipe pressure has the advantage that it can be constructed at a lower cost than the former.
しかしながら、空燃比の制御精度が低く、特
に、加速時においては、吸気管圧力が増大しなけ
れば燃料噴射量が増えないため、空燃比が一時的
にリーンとなつて、加速性能が低いものであつ
た。
このような問題点を解消するべく、従来は、絞
り弁に配設された櫛歯状のセンサから出力される
パルス列に応じて加速増量を行うようにしていた
が、ドライバビリテイを高めるためには、増量の
量を非常に大としなければならず、その場合に
は、空燃比がオーバーリツチとなつて、排気ガス
中の一酸化炭素量が異常に増大し、空燃比を三元
触媒コンバータに適した所定範囲内に維持するこ
とができなかつた。これは、排気下流側に配設し
た酸素濃度センサの出力信号に応じて燃料噴射量
をフイードバツク制御するようにした場合におい
ても、酸素濃度センサの応答が遅いため、同様で
ある。
従つて従来は、吸気管圧力感知式の電子制御燃
料噴射装置を、空燃比を精密に制御することが必
要な、排気ガス浄化対策が施された自動車用エン
ジンに用いることは困難であると考えられてい
た。
本発明は、前記従来の問題点を解消するべくな
されたもので、加速時に、アクセルペダルの踏み
方（即ちアイドルスイツチの状態と絞り弁開度）
の吸気管圧力の両者、及び、エンジン暖機状態に
よるエンジン要求特性の変化に見合つた、適切
な、過度とならない増量補正を行つて、空燃比を
理論空燃比近傍に維持することができ、従つて、
良好な過渡応答性能と排気ガス浄化性能を両立さ
せることができる内燃機関の電子制御燃料噴射方
法を提供することを目的とする。
However, the control accuracy of the air-fuel ratio is low, and especially during acceleration, the fuel injection amount cannot be increased unless the intake pipe pressure increases, so the air-fuel ratio temporarily becomes lean, resulting in poor acceleration performance. It was hot. In order to solve these problems, conventionally the acceleration was increased according to the pulse train output from a comb-like sensor installed in the throttle valve, but in order to improve drivability, In this case, the amount of increase must be very large, and in that case, the air-fuel ratio becomes overrich, the amount of carbon monoxide in the exhaust gas increases abnormally, and the air-fuel ratio is changed to a three-way catalytic converter. could not be maintained within a suitable predetermined range. This is the same even when the fuel injection amount is feedback-controlled in accordance with the output signal of the oxygen concentration sensor disposed downstream of the exhaust gas because the response of the oxygen concentration sensor is slow. Therefore, in the past, it was thought that it would be difficult to use an electronically controlled fuel injection system that senses intake pipe pressure in an automobile engine that requires precise control of the air-fuel ratio and that takes measures to purify exhaust gas. It was getting worse. The present invention was made to solve the above-mentioned conventional problems, and it is possible to determine how the accelerator pedal is pressed (i.e., the state of the idle switch and the opening degree of the throttle valve) during acceleration.
It is possible to maintain the air-fuel ratio near the stoichiometric air-fuel ratio by making appropriate and not excessive increase corrections commensurate with both the intake pipe pressure and the change in engine required characteristics due to the engine warm-up state. Then,
An object of the present invention is to provide an electronically controlled fuel injection method for an internal combustion engine that can achieve both good transient response performance and exhaust gas purification performance.
本発明は、エンジンの吸気管圧力とエンジン回
転数に応じて基本噴射量を求めると共に、過渡時
は、エンジン運転状態に応じて算出される補正係
数により前記基本噴射量を補正することによつて
燃料噴射量を決定するようにした内燃機関の電子
制御燃料噴射方法において、加速時に、アイドル
スイツチがオフとなつた時に補正係数を増大さ
せ、次いで、所定の減衰速度で減衰させるアフタ
アイドル増量と、絞り弁開度の所定期間毎の変化
量に応じた値を積算した値を補正係数とすること
により、絞り弁開度の増大速度に応じて補正係数
を増大させ、次いで、所定の減衰速度で減衰させ
る絞り弁開度増量と、吸気管圧力の所定期間毎の
変化量に応じた値の積算した値を補正係数とする
ことにより、吸気管圧力の増大速度に応じて補正
係数を増大させ、次いで、所定の減衰速度で減衰
させる吸気管圧力増量とを算出し、これら増量値
のうち、その最大値を用いて加速増量を行うと共
に、前記減衰途中で、前記補正係数がエンジン暖
機状態に応じて変化する所定レベル迄減衰した時
に、前記減衰速度を低速に切換えるようにして、
前記目的を達成したものである。
The present invention calculates the basic injection amount according to the engine intake pipe pressure and engine rotation speed, and during transient periods, corrects the basic injection amount using a correction coefficient calculated according to the engine operating state. In an electronically controlled fuel injection method for an internal combustion engine that determines the fuel injection amount, the after-idle amount increase is performed by increasing a correction coefficient when an idle switch is turned off during acceleration, and then attenuating at a predetermined decay speed; By setting a value obtained by integrating values corresponding to the amount of change in the throttle valve opening for each predetermined period as a correction coefficient, the correction coefficient is increased according to the increasing speed of the throttle valve opening, and then at a predetermined damping speed. The correction coefficient is increased according to the rate of increase in the intake pipe pressure by using the sum of the values corresponding to the increase in the opening of the throttle valve to be damped and the amount of change in the intake pipe pressure every predetermined period as a correction coefficient. Next, an increase in intake pipe pressure to be attenuated at a predetermined attenuation speed is calculated, and among these increase values, the maximum value is used to perform an acceleration increase. When the attenuation reaches a predetermined level that changes accordingly, the attenuation speed is switched to a low speed,
The above objective has been achieved.
本発明においては、加速時に、アクセルペダル
を踏んだ瞬間に増量補正を行う、極めて応答の早
いアフタアイドル増量と、吸気管圧力の増大に先
行して絞り弁開度の増大速度に応じた増量補正を
行う、応答の早い絞り弁開度増量と、吸気管圧力
の増大に応じた増量補正を行う、精度の高い吸気
管圧力増量と、を組合せて増量補正を行うように
しているので、応答が早く、且つ、精度の高い加
速増量を行うことができる。
即ち、前記アフタアイドル増量は、応答は極め
て早いが、どの程度の加速か判断できないため、
見込み補正しかできず、オーバーリツチ防止の観
点から多くの増量値とすることはできない。
又、前記絞り弁開度増量は、絞り弁開度に基づ
いて行われるため、アクセルペダルの踏み方に応
じた増量を迅速に行うことができ、高精度の吸気
管圧力増量が行われる迄の中間加速部分の応答性
を向上させることができる。
これらに対して、前記吸気管圧力増量は、絞り
弁開度が変化した後で吸気管圧力の変化が生じて
から行われる。この吸気管圧力増量は、実際にエ
ンジン燃焼室に吸入される空気量に基づいて行わ
れるものであり、精度が高い。
なお、吸入空気量感知式の場合には、加速時に
絞り弁が開かれると、絞り弁より上流側のエアフ
ローセンサ出力は直ちに吸入空気量の増加を検出
するのに対し、実際に燃焼室に吸入される空気量
は、絞り弁より下流側のサージタンクの分だけ増
加が遅れるため、前記センサ出力により計算され
る燃料量の方が先行して増加することになり、こ
れが適当な加速増量となるため、本発明のような
絞り弁開度増量を必要としない。
本発明においては、更に、前記アフタアイドル
増量、絞り弁開度増量及び吸気管圧力増量の最大
値を辿つて加速増量を行うようにしているので、
これらが重なる領域でも過増量となることがな
い。
又、前記減衰途中で、前記補正係数がエンジン
暖機状態に応じて変化する所定レベル迄減衰した
時に、前記減衰速度を低速に切換えるようにして
いるので、エンジン暖機状態によるエンジン要求
特性の変化に見合つた適切な加速増量が行われ
る。
In the present invention, during acceleration, the after-idle amount increase is performed at the moment the accelerator pedal is pressed, and the after-idle amount increases with extremely quick response.The amount is also increased in accordance with the rate of increase in the throttle valve opening prior to the increase in intake pipe pressure. Since the increase correction is performed by combining the throttle valve opening increase with a quick response, which performs the Acceleration increase can be performed quickly and with high precision. In other words, although the after-idle increase has an extremely quick response, it is not possible to determine how much acceleration the engine is accelerating.
Only estimated corrections can be made, and it is not possible to increase the amount by a large amount in order to prevent over-richness. In addition, since the throttle valve opening is increased based on the throttle valve opening, it can be quickly increased depending on how the accelerator pedal is pressed, and the intake pipe pressure can be increased with high accuracy. The responsiveness of the intermediate acceleration portion can be improved. On the other hand, the intake pipe pressure increase is performed after the intake pipe pressure changes after the throttle valve opening changes. This intake pipe pressure increase is performed based on the amount of air actually taken into the engine combustion chamber, and is highly accurate. In the case of the intake air amount sensing type, when the throttle valve is opened during acceleration, the air flow sensor output upstream of the throttle valve immediately detects an increase in the amount of intake air, whereas Since the increase in the amount of air caused by the throttle valve is delayed by the amount of the surge tank downstream from the throttle valve, the amount of fuel calculated from the sensor output increases in advance, and this becomes an appropriate increase in acceleration. Therefore, there is no need to increase the throttle valve opening as in the present invention. In the present invention, the acceleration increase is further performed by following the maximum values of the after-idle increase, the throttle valve opening increase, and the intake pipe pressure increase.
Even in the area where these overlap, the amount will not be increased excessively. Furthermore, during the attenuation, when the correction coefficient attenuates to a predetermined level that changes depending on the engine warm-up state, the attenuation speed is switched to a low speed, so that changes in engine required characteristics due to the engine warm-up state are avoided. Appropriate acceleration increases commensurate with the
以下、図面を参照して、本発明の実施例を詳細
に説明する。
本発明に係る内燃機関の電子制御燃料噴射方法
が採用された吸気管圧力感知式の電子制御燃料噴
射装置の実施例は、第１図及び第２図に示す如
く、外気を取入れるためのエアクリーナ１２と、
該エアクリーナ１２より取入れられた吸入空気の
温度を検出するための吸気温センサ１４と、吸気
通路１６中に配設され、運転席に配設されたアク
セルペダル（図示省略）と連動して開閉するよう
にされた、吸入空気の流量を制御するための絞り
弁１８と、該絞り弁１８がアイドル開度にあるか
否かを検出するためのアイドル接点（スイツチ）
及び絞り弁１８の開度に比例した電圧出力を発生
するポテンシヨメータを含むスロツトルセンサ２
０と、気筒間の吸気干渉を防止するためのサージ
タンク２２と、該サージタンク２２内の圧力から
吸気管圧力を検出するための吸気管圧力センサ２
３と、前記絞り弁１８をバイパスするバイパス通
路２４と、該バイパス通路２４の途中に配設さ
れ、該バイパス通路２４の開口面積を制御するこ
とによつて、アイドル回転速度を制御するための
アイドル回転制御弁２６と、吸気マニホールド２
８に配設された、エンジン１０の吸気ポートに向
けて燃料を噴射するためのインジエクタ３０と、
排気マニホールド３２に配設された、排気ガス中
の残存酸素濃度から空燃比を検知するための酸素
濃度センサ３４と、前記排気マニホールド３２下
流側の排気管３６の途中に配設された三元触媒コ
ンバータ３８と、エンジン１０のクランク軸の回
転と連動して回転するデイストリビユータ軸を有
するデイストリビユータ４０と、該デイストリビ
ユータ４０に内蔵された、前記デイストリビユー
タ軸の回転に応じて上死点信号及びクランク角信
号を出力する上死点センサ４２及びクランク角セ
ンサ４４と、エンジンブロツクに配設された、エ
ンジン冷却水温を検知するための冷却水温センサ
４６と、変速機４８の出力軸の回転数から車両の
走行速度を検出するための車速センサ５０と、前
記吸気管圧力センサ２３出力の吸気管圧力と前記
クランク角センサ４４の出力から求められるエン
ジン回転数に応じて、エンジン１工程あたりの基
本噴射量を求めると共に、これを前記スロツトル
センサ２０の出力、前記酸素濃度センサ３４出力
の空燃比、前記冷却水温センサ４６出力のエンジ
ン冷却水温等に応じて補正することによつて、燃
料噴射量を決定して前記インジエクタ３０に開弁
時間信号を出力し、又、エンジン運転状態に応じ
て点火時期を決定してイグナイタ付コイル５２に
点火信号を出力し、更に、アイドル時に前記アイ
ドル回転制御弁２６を制御するデジタル制御回路
５４とを備えた自動車用エンジン１０の吸気管圧
力感知式電子制御燃料噴射装置において、前記デ
ジタル制御回路５４内で、前記スロツトルセンサ
２０のアイドルスイツチの変化状態、前記スロツ
トルセンサ２０のポテンシヨメータ出力から検知
される絞り弁開度の変化状態、及び、前記吸気管
圧力センサ２３の出力から検知される吸気管圧力
の変化状態に応じて、加速時に補正係数を増大さ
せ、次いで、所定の減衰速度で減衰させることに
よつて加速増量を行うと共に、減衰途中で、前記
補正係数が、エンジン冷却水温に応じて変化する
所定レベルまで減衰した時に、前記減衰速度を低
速に切換えるようにしたものである。
前記デジタル制御回路５４は、第２図に詳細に
示す如く、各種演算処理を行うマイクロプロセツ
サからなる中央処理装置（以下CPUと称する）
６０と、前記吸気温センサ１４、スロツトルセン
サ２０のポテンシヨメータ、吸気管圧力センサ２
３、酸素濃度センサ３４、冷却水温センサ４６等
から入力されるアナログ信号を、デジタル信号に
変換して順次CPU６０に取込むためのマルチプ
レクサ付アナログ入力ポート６２と、前記スロツ
トルセンサ２０のアイドルスイツチ、上死点セン
サ４２、クランク角センサ４４、車速センサ５０
等から入力されるデジタル信号を、所定のタイミ
ングでCPU６０に取込むためのデジタル入力ポ
ート６４と、プログラムあるいは各種定数等を記
憶するためのリードオンリーメモリ（以下ROM
と称する）６６と、CPU６０における演算デー
タ等を一時的に記憶するためのランダムアクセス
メモリ（以下RAMと称する）６８と、機関停止
時にも補助電源から給電されて記憶を保持できる
バツクアツプ用ランダムアクセスメモリ（以下バ
ツクアツプRAMと称する）７０と、CPU６０に
おける演算結果を、所定のタイミングで前記アイ
ドル回転制御弁２６、インクジエクタ３０、イグ
ナイタ付コイル５２等に出力するためのデジタル
出力ポート７２と、上記各構成機器間を接続する
コモンバス７４とから構成されている。
以下、実施例の作用を説明する。
まずデジタル制御回路５４は、吸気管圧力セン
サ２３出力の吸気管圧力PMと、クランク角セン
サ４４の出力から算出されるエンジン回転数NE
により、ROM６６に予め記憶されているマツプ
から基本噴射時間TP（PM、NE）を読出す。
更に、各センサからの信号に応じて、次式を用
いて前記基本噴射時間TP（PM、NE）を補正す
ることにより、燃料噴射時間TAUを算出する。
TAU＝TP（PM、NE）＊（１＋Ｋ＊Ｆ）…… (1)
ここで、Ｆは、補正係数で、Ｆが正である場合
には増量補正を表わし、Ｆが負である場合には減
量補正を表わしている。又、Ｋは、前記補正係数
Ｆを更に補正するための補正倍率であり、通常は
１とされている。
このようにして決定された燃料噴射時間TAU
に対応する燃料噴射信号が、インジエクタ３０に
出力され、エンジン回転と同期してインジエクタ
３０が燃料噴射時間TAUだけ開かれて、エンジ
ン１０の吸気マニホールド２８内に燃料が噴射さ
れる。
本実施例における加速増量は、次のようにして
行われる。
即ち、第３図に示す如く、加速時に、アクセル
ペダルが踏み込まれ、スロツトルセンサ２０のア
イドルスイツチが、第３図Ａに示す如く、時刻t1
でオフとなると、絞り弁開度TA及び吸気管圧力
PMの増大に先行して、第３図Ｄに実線Ａで示す
ような、極めて迅速な増量補正を行うアフタアイ
ドル増量（以下LL増量と称する）が行われる。
このLL増量は、具体的には、例えば、補正係
数Ｆを、まず、正の所定値とし、次いで、エンジ
ン回転毎あるいは一定時間毎に所定の減衰速度で
０まで減衰させることによつて行われる。
次いで、絞り弁１８が更に開かれ、前記スロツ
トルセンサ２０のポテンシヨンメータ出力から検
知される絞り弁開度TAが、第３図Ｂに示す如
く、時刻t2で立上り始めると、吸気管圧力PMの
増大に先行して、第３図Ｄに実線Ｂで示すよう
な、絞り弁開度TAの増大速度に応じた迅速な増
量補正を行う絞り弁開度増量（以下TA増量と称
する）が行われる。
このTA増量は、具体的には、例えば、絞り弁
開度TAの所定時間毎の変化量に応じた値を積算
した値（正値）を補正係数Ｆとし、次いで、エン
ジン回転毎あるいは一定時間毎に、エンジン冷却
水温に応じて変化する所定レベルＬまでは高速
の、所定レベルＬ到達後は低速の、所定減衰速度
ΔF1、ΔF2（ΔF1＞ΔF2）で０まで減衰させること
によつて行われる。
更に、吸気管圧力PMが絞り弁開度TAの増大
に遅れて増大し始めると、時刻t3から、第３図Ｄ
に実線Ｃで示すような、吸気管圧力PMの増大速
度に応じた精度の高い増量補正を行う吸気管圧力
増量（以下PM増量と称する）が行われる。
このPM増量は、具体的には、例えば、吸気管
圧力PMの所定時間毎の変化量に応じた値を積算
した値（正値）を補正係数Ｆとし、次いで、エン
ジン回転毎あるいは一定時間毎に、エンジン冷却
水温に応じて変化する所定レベルＬまでは高速
の、所定レベルＬ到達後は低速の、所定減衰速度
ΔF1、ΔF2（ΔF1＞ΔF2）で０まで減衰させること
によつて行われる。
前記TA増量及びPM増量における補正係数Ｆ
の減衰速度の切換えは、エンジン冷却水温が高い
暖機終了後の状態では、第４図に実線Ｄで示す如
く、比較的低い所定レベルL1で行われ、一方、
エンジン冷却水温が低いエンジン暖機中の状態で
は、同じく第４図に実線Ｅで示す如く、比較的高
い所定レベルL2で行われるので、エンジン暖機
状態によるエンジン要求特性の変化に見合つた適
切な加速増量が行われる。
この加速増量の補正係数Ｆの減衰のプログラム
を第５図に示す。
これに対して、従来の吸入空気量感知式の電子
制御燃料噴射装置においては、エンジン暖機状態
に拘らず、加速終了後の所定時間経過時（時刻
t5）に減衰速度を低速に切換えるようにしていた
ため、エンジン暖機中における加速増量特性は、
第４図に破線Ｆで示す如くとなり、斜線領域が過
増量となつて、空燃比がオーバーリツチとなつて
いたものである。
なお、時刻t2〜t3ではLL増量とTA増量が重な
り、又、時刻t3〜t4では全ての増量が重なり、更
に、時刻t4〜t6ではTA増量とPM増量が重なつて
いるが、全ての増量を重畳して増量補正を行つて
しまうと、特に、応答は早いが精度の良くない
LL増量、TA増量の影響で、過増量となる恐れが
ある。
従つて、本発明においては、第３図Ｄに太い実
線で示す如く、前記LL増量、TA増量、PM増量
の最大値を辿つて加速増量を行うようにしてい
る。
前記のようにして、極めて応答の早いLL増量、
応答の早いTA増量、精度の高いPM増量を組合
せて加速増量を行うことによつて、アクセルペダ
ルを早く組み込んだ場合には多量の増量が実施さ
れ、一方、アクセルペダルを徐々に踏み込んだ場
合には少量の増量が行われる等、アクセルペダル
の踏み方に応じた適切な増量を実現することがで
き、空燃比を理論空燃比近傍に維持して、過渡応
答性能と排気ガス浄化性能を両立することができ
る。
なお、前記実施例においては、エンジン暖機状
態を、エンジン冷却水温から検知するようにして
いたが、エンジン暖機状態を検知する方法はこれ
に限定されず、例えば、エンジン温度、あるい
は、エンジン始動後の経過時間から検知すること
も可能である。
又、前記実施例においては、TA増量及びPM
増量の減衰途中で、同一の所定レベル到達時に、
減衰速度の切換えを行うようにしていたが、エン
ジンの要求特性によつては、TA増量とPM増量
で減衰速度の切換えレベルを変えたり、あるい
は、LL増量でも、減衰速度の切換えを行つたり
することが可能である。
Embodiments of the present invention will be described in detail below with reference to the drawings. An embodiment of the intake pipe pressure sensing type electronically controlled fuel injection device in which the electronically controlled fuel injection method for an internal combustion engine according to the present invention is adopted is as shown in FIGS. 1 and 2. 12 and
An intake temperature sensor 14 for detecting the temperature of the intake air taken in from the air cleaner 12 is disposed in the intake passage 16, and opens and closes in conjunction with an accelerator pedal (not shown) disposed in the driver's seat. A throttle valve 18 for controlling the flow rate of intake air, and an idle contact (switch) for detecting whether or not the throttle valve 18 is at an idle opening.
and a throttle sensor 2 including a potentiometer that generates a voltage output proportional to the opening degree of the throttle valve 18.
0, a surge tank 22 for preventing intake air interference between cylinders, and an intake pipe pressure sensor 2 for detecting intake pipe pressure from the pressure inside the surge tank 22.
3, a bypass passage 24 that bypasses the throttle valve 18, and an idler disposed in the middle of the bypass passage 24 for controlling the idle rotation speed by controlling the opening area of the bypass passage 24. Rotation control valve 26 and intake manifold 2
an injector 30 disposed at 8 for injecting fuel toward the intake port of the engine 10;
An oxygen concentration sensor 34 disposed in the exhaust manifold 32 for detecting the air-fuel ratio from the residual oxygen concentration in the exhaust gas, and a three-way catalyst disposed midway in the exhaust pipe 36 on the downstream side of the exhaust manifold 32. a converter 38; a distributor 40 having a distributor shaft that rotates in conjunction with the rotation of the crankshaft of the engine 10; A top dead center sensor 42 and a crank angle sensor 44 that output a dead center signal and a crank angle signal, a cooling water temperature sensor 46 disposed in the engine block to detect the engine cooling water temperature, and an output shaft of the transmission 48. The vehicle speed sensor 50 detects the running speed of the vehicle based on the rotation speed of the engine, and the engine speed is determined based on the engine rotation speed determined from the intake pipe pressure output from the intake pipe pressure sensor 23 and the output of the crank angle sensor 44. By determining the basic injection amount per hour and correcting this according to the output of the throttle sensor 20, the air-fuel ratio of the output of the oxygen concentration sensor 34, the engine coolant temperature of the output of the coolant temperature sensor 46, etc. It determines the fuel injection amount and outputs a valve opening time signal to the injector 30, determines the ignition timing according to the engine operating state and outputs an ignition signal to the igniter-equipped coil 52, and further, In the intake pipe pressure sensing type electronically controlled fuel injection system for the automobile engine 10, which is equipped with a digital control circuit 54 that controls the rotation control valve 26, in the digital control circuit 54, changes in the idle switch of the throttle sensor 20 are performed. during acceleration, the throttle valve opening degree detected from the potentiometer output of the throttle sensor 20, and the intake pipe pressure detected from the output of the intake pipe pressure sensor 23. Acceleration is increased by increasing the correction coefficient and then damping it at a predetermined damping speed. The damping speed is switched to a low speed. As shown in detail in FIG. 2, the digital control circuit 54 is a central processing unit (hereinafter referred to as CPU) consisting of a microprocessor that performs various arithmetic operations.
60, the intake temperature sensor 14, the potentiometer of the throttle sensor 20, and the intake pipe pressure sensor 2.
3. An analog input port 62 with a multiplexer for converting analog signals input from the oxygen concentration sensor 34, cooling water temperature sensor 46, etc. into digital signals and sequentially inputting them to the CPU 60; and an idle switch for the throttle sensor 20; Top dead center sensor 42, crank angle sensor 44, vehicle speed sensor 50
A digital input port 64 is used to input digital signals input from other devices into the CPU 60 at predetermined timing, and a read-only memory (hereinafter referred to as ROM) is used to store programs or various constants.
) 66, a random access memory (hereinafter referred to as RAM) 68 for temporarily storing calculation data etc. in the CPU 60, and a backup random access memory that can be supplied with power from an auxiliary power source and retain memory even when the engine is stopped. (hereinafter referred to as backup RAM) 70, a digital output port 72 for outputting the calculation results of the CPU 60 to the idle rotation control valve 26, injector 30, coil with igniter 52, etc. at a predetermined timing, and each of the above-mentioned components. and a common bus 74 that connects between the two. The effects of the embodiment will be explained below. First, the digital control circuit 54 calculates the intake pipe pressure PM output from the intake pipe pressure sensor 23 and the engine rotation speed NE calculated from the output of the crank angle sensor 44.
Accordingly, the basic injection time TP (PM, NE) is read from the map stored in the ROM 66 in advance. Furthermore, the fuel injection time TAU is calculated by correcting the basic injection time TP (PM, NE) using the following equation according to the signals from each sensor. TAU=TP(PM,NE)*(1+K*F)... (1) Here, F is a correction coefficient; if F is positive, it represents an increase correction; if F is negative, Represents weight loss correction. Further, K is a correction magnification for further correcting the correction coefficient F, and is normally set to 1. Fuel injection time TAU determined in this way
A fuel injection signal corresponding to this is output to the injector 30, the injector 30 is opened for the fuel injection time TAU in synchronization with the engine rotation, and fuel is injected into the intake manifold 28 of the engine 10. The accelerated increase in amount in this embodiment is performed as follows. That is, as shown in FIG. 3, the accelerator pedal is depressed during acceleration, and the idle switch of the throttle sensor 20 is activated at time t 1 as shown in FIG. 3A.
When it turns off, the throttle valve opening TA and intake pipe pressure
Prior to the increase in PM, after-idle power increase (hereinafter referred to as LL power increase) is performed, which performs extremely rapid power increase correction, as shown by the solid line A in FIG. 3D. Specifically, this LL increase is performed by, for example, first setting the correction coefficient F to a predetermined positive value, and then attenuating it to 0 at a predetermined damping speed every engine rotation or every fixed time. . Next, the throttle valve 18 is further opened, and when the throttle valve opening TA detected from the potentiometer output of the throttle sensor 20 starts to rise at time t2 as shown in FIG. 3B, the intake pipe pressure increases. Prior to the increase in PM, as shown by the solid line B in Figure 3D, the throttle valve opening is increased (hereinafter referred to as TA increase), which performs a rapid increase correction according to the rate of increase in the throttle valve opening TA. It will be done. Specifically, this TA increase is performed by setting the correction coefficient F to a value (positive value) that is the sum of the values corresponding to the amount of change in the throttle valve opening TA every predetermined time, and The damping speed is set to 0 at predetermined damping speeds ΔF 1 and ΔF 2 (ΔF 1 >ΔF 2 ), which is fast until a predetermined level L that changes according to the engine cooling water temperature, and slow after reaching the predetermined level L. It is done by folding. Furthermore, when the intake pipe pressure PM begins to increase with a delay in the increase in the throttle valve opening TA, from time t 3 , Fig. 3D
As shown by a solid line C, an intake pipe pressure increase (hereinafter referred to as PM increase) is performed that performs a highly accurate increase correction according to the rate of increase in intake pipe pressure PM. Specifically, this PM increase is performed, for example, by setting the correction coefficient F to a value (positive value) that is the sum of values corresponding to the amount of change in intake pipe pressure PM at each predetermined time interval, and By damping down to 0 at predetermined damping speeds ΔF 1 and ΔF 2 (ΔF 1 >ΔF 2 ), which are fast up to a predetermined level L that changes according to the engine cooling water temperature, and slow after reaching the predetermined level L. It is carried out with Correction coefficient F for the TA increase and PM increase
The switching of the damping speed is performed at a relatively low predetermined level L 1 as shown by the solid line D in FIG.
When the engine is warming up and the engine cooling water temperature is low, as shown by the solid line E in Fig. 4, the control is performed at a relatively high predetermined level L2 . Accelerated increase in dosage is carried out. A program for attenuating the correction coefficient F for this acceleration increase is shown in FIG. On the other hand, in the conventional electronically controlled fuel injection system that detects the amount of intake air, regardless of the warm-up state of the engine, the fuel injection device
Since the damping speed was switched to a low speed at t5 ), the acceleration increase characteristics during engine warm-up were as follows.
The result is as shown by the broken line F in FIG. 4, where the shaded area represents an excessive increase in fuel consumption and the air-fuel ratio becomes overrich. Note that from time t 2 to t 3 , the LL increase and TA increase overlap, from time t 3 to t 4 , all the increases overlap, and furthermore, from time t 4 to t 6 , the TA increase and PM increase overlap. However, if all the increases are superimposed and the increase correction is performed, the response is fast but the accuracy is not good.
Due to the effects of increasing LL and TA, there is a risk of overdosing. Therefore, in the present invention, as shown by the thick solid line in FIG. 3D, the accelerated increase is performed by following the maximum values of the LL increase, TA increase, and PM increase. As mentioned above, LL increase with extremely quick response,
By combining a quick response TA increase and a highly accurate PM increase to increase acceleration, a large amount is increased when the accelerator pedal is applied early, while a large amount is increased when the accelerator pedal is gradually depressed. It is possible to realize an appropriate increase in fuel volume depending on how the accelerator pedal is pressed, such as a small increase in fuel volume, and maintain the air-fuel ratio near the stoichiometric air-fuel ratio, achieving both transient response performance and exhaust gas purification performance. be able to. In the above embodiment, the engine warm-up state is detected from the engine cooling water temperature, but the method for detecting the engine warm-up state is not limited to this. It is also possible to detect from the later elapsed time. In addition, in the above example, TA increase and PM
During the decay of the increase, when the same predetermined level is reached,
It was designed to switch the damping speed, but depending on the required characteristics of the engine, the switching level of the damping speed can be changed by increasing the TA amount and the PM amount, or even by increasing the LL amount. It is possible to do so.
以上説明した通り、本発明によれば、アクセル
ペダルの踏み方と吸気管圧力の両者、及び、エン
ジン暖機状態によるエンジン要求特性の変化に見
合つた、適切な過度とならない増量補正を行うこ
とができ、空燃比を理論空燃比近傍に維持して、
良好な過渡応答性能と排気ガス浄化性能を両立す
ることができる。従つて、吸気管圧力感知式の電
子制御燃料噴射装置を用いた場合でも、精密な空
燃比制御を行うことが可能となるという優れた効
果を有する。
As explained above, according to the present invention, it is possible to perform an appropriate and not excessive increase correction commensurate with changes in engine required characteristics due to both the way the accelerator pedal is depressed and the intake pipe pressure, and the engine warm-up state. The air-fuel ratio can be maintained near the stoichiometric air-fuel ratio,
It is possible to achieve both good transient response performance and exhaust gas purification performance. Therefore, even when using an electronically controlled fuel injection device that senses intake pipe pressure, there is an excellent effect in that precise air-fuel ratio control can be performed.
第１図は、本発明に係る内燃機関の電子制御燃
料噴射方法が採用された、自動車用エンジンの吸
気管圧力感知式電子制御燃料噴射装置の実施例を
示すブロツク線図、第２図は、前記実施例で用い
られているデジタル制御回路の構成を示すブロツ
ク線図、第３図は、前記実施例における加速増量
の様子を示す線図、第４図は、同じく、加速増量
の減衰の様子を示す線図、第５図は、同じく、加
速増量の減衰のプログラムを示す流れ図である。
１０……エンジン、１４……吸気温センサ、１
８……絞り弁、２０……スロツトルセンサ、２３
……吸気管圧力センサ、３０……インジエクタ、
３４……酸素濃度センサ、４０……デイストリビ
ユータ、４２……上死点センサ、４４……クラン
ク角センサ、４６……冷却水温センサ、５４……
デジタル制御回路。
FIG. 1 is a block diagram showing an embodiment of an intake pipe pressure sensing type electronically controlled fuel injection device for an automobile engine in which the electronically controlled fuel injection method for an internal combustion engine according to the present invention is adopted, and FIG. FIG. 3 is a block diagram showing the configuration of the digital control circuit used in the embodiment, FIG. 3 is a diagram showing the acceleration increase in the embodiment, and FIG. 4 is a diagram showing the attenuation of the acceleration increase. FIG. 5 is also a flowchart showing the program for the attenuation of the acceleration increase. 10...Engine, 14...Intake temperature sensor, 1
8... Throttle valve, 20... Throttle sensor, 23
...Intake pipe pressure sensor, 30...Injector,
34... Oxygen concentration sensor, 40... Distributor, 42... Top dead center sensor, 44... Crank angle sensor, 46... Cooling water temperature sensor, 54...
Digital control circuit.
Claims (1)
じて基本噴射量を求めると共に、過渡時は、エン
ジン運転状態に応じて算出される補正係数により
前記基本噴射量を補正することによつて燃料噴射
量を決定するようにした内燃機関の電子制御燃料
噴射方法において、 加速時に、 アイドルスイツチがオフとなつた時に補正係数
を増大させ、次いで、所定の減衰速度で減衰させ
るアフタアイドル増量と、 絞り弁開度の所定期間毎の変化量に応じた値を
積算した値を補正係数とすることにより、絞り弁
開度の増大速度に応じて補正係数を増大させ、次
いで、所定の減衰速で減衰させる絞り弁開度増量
と、 吸気管圧力の所定期間毎の変化量に応じた値を
積算した値を補正係数とすることにより、吸気管
圧力の増大速度に応じて補正係数を増大させ、次
いで、所定の減衰速度で減衰させる吸気管圧力増
量とを算出し、 これら増量値のうち、その最大値を用いて加速
増量を行うと共に、 前記減衰途中で、前記補正係数がエンジン暖機
状態に応じて変化する所定レベル迄減衰した時
に、前記減衰速度を低速に切換えることを特徴と
する内燃機関の電子制御燃料噴射方法。[Scope of Claims] 1. The basic injection amount is determined according to the engine intake pipe pressure and the engine speed, and during transient periods, the basic injection amount is corrected using a correction coefficient calculated according to the engine operating state. In an electronically controlled fuel injection method for an internal combustion engine in which the amount of fuel injection is determined by The correction coefficient is increased according to the rate of increase in the throttle valve opening, and then the correction coefficient is increased according to the rate of increase in the throttle valve opening, and then the correction coefficient is increased according to the rate of increase in the throttle valve opening. By setting the correction coefficient as a value that is the sum of the increase in throttle valve opening that is attenuated by the damping speed and the amount of change in intake pipe pressure for each predetermined period, the correction coefficient can be adjusted according to the rate of increase in intake pipe pressure. The intake pipe pressure is increased, and then the intake pipe pressure is attenuated at a predetermined attenuation speed. Among these increase values, the maximum value is used to increase the intake pipe pressure during acceleration. An electronically controlled fuel injection method for an internal combustion engine, characterized in that the attenuation speed is switched to a low speed when the attenuation reaches a predetermined level that changes depending on the machine state.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2784582A JPS58144634A (en) | 1982-02-23 | 1982-02-23 | Method for electronically controlling fuel injection in internal-combustion engine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2784582A JPS58144634A (en) | 1982-02-23 | 1982-02-23 | Method for electronically controlling fuel injection in internal-combustion engine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58144634A JPS58144634A (en) | 1983-08-29 |
| JPH059620B2 true JPH059620B2 (en) | 1993-02-05 |
Family
ID=12232249
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2784582A Granted JPS58144634A (en) | 1982-02-23 | 1982-02-23 | Method for electronically controlling fuel injection in internal-combustion engine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58144634A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61151052U (en) * | 1985-03-11 | 1986-09-18 | ||
| JP2699075B2 (en) * | 1987-10-27 | 1998-01-19 | 株式会社ユニシアジェックス | Fuel supply device for internal combustion engine |
| JPH01232135A (en) * | 1988-03-10 | 1989-09-18 | Mazda Motor Corp | Accelerating fuel control device for engine |
| JPH02275036A (en) * | 1989-04-18 | 1990-11-09 | Mitsubishi Motors Corp | Fuel controller for engine |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55109733A (en) * | 1979-02-15 | 1980-08-23 | Nippon Denso Co Ltd | Acceleration increasing-rate control method in electronically-controlled fuel injector |
| JPS56124638A (en) * | 1980-03-07 | 1981-09-30 | Toyota Motor Corp | Method of controlling fuel supply to internal combustion engine |
-
1982
- 1982-02-23 JP JP2784582A patent/JPS58144634A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55109733A (en) * | 1979-02-15 | 1980-08-23 | Nippon Denso Co Ltd | Acceleration increasing-rate control method in electronically-controlled fuel injector |
| JPS56124638A (en) * | 1980-03-07 | 1981-09-30 | Toyota Motor Corp | Method of controlling fuel supply to internal combustion engine |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS58144634A (en) | 1983-08-29 |
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