JP3727357B2 - 4-cycle engine fuel injection control system - Google Patents

4-cycle engine fuel injection control system Download PDF

Info

Publication number
JP3727357B2
JP3727357B2 JP26385192A JP26385192A JP3727357B2 JP 3727357 B2 JP3727357 B2 JP 3727357B2 JP 26385192 A JP26385192 A JP 26385192A JP 26385192 A JP26385192 A JP 26385192A JP 3727357 B2 JP3727357 B2 JP 3727357B2
Authority
JP
Japan
Prior art keywords
intake
valve
fuel injection
intake passage
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.)
Expired - Fee Related
Application number
JP26385192A
Other languages
Japanese (ja)
Other versions
JPH06117297A (en
Inventor
義治 井坂
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Yamaha Motor Co Ltd
Original Assignee
Yamaha Motor Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Yamaha Motor Co Ltd filed Critical Yamaha Motor Co Ltd
Priority to JP26385192A priority Critical patent/JP3727357B2/en
Publication of JPH06117297A publication Critical patent/JPH06117297A/en
Application granted granted Critical
Publication of JP3727357B2 publication Critical patent/JP3727357B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/40—Engine management systems

Landscapes

  • Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)

Description

【０００１】
【産業上の利用分野】
本発明は、４サイクルエンジンの燃料噴射制御装置に関し、特に低負荷域での燃焼安定性を確保でき、さらには高負荷域でのオーバリッチを解消できる装置に関する。
【０００２】
【従来の技術】
燃焼室に燃料を噴射する燃料噴射弁と、吸気通路断面積を可変制御する吸気制御弁とを備えた４サイクルエンジンが提案されている。この種のエンジンでは、通常燃料噴射弁による燃料の噴射は、吸気弁が閉じた各排気行程において該吸気弁のバルブヘット背面に向けてそれぞれ１回ずつ行われている。排気行程で吸気弁に噴射された燃料は気化し、混合気が吸気行程において燃焼室内に導入されることになる。一方、低速回転時等の吸気量の少ない場合には、吸気制御弁が吸気通路断面積を減少させる。これにより、吸気の流速が高められて吸気に方向性が生じ、リーン燃焼（希薄空燃比燃焼）を安定化させることができる。
【０００３】
【発明が解決しようとする課題】
ところが上記エンジンにおいて、低速回転かつ低負荷の場合には、燃料の噴射量が減る結果、燃焼状態が不安定となるおそれがある。そこで本発明者は、低負荷時等には点火プラグ近傍に燃料を集中させる成層化を図ることによりリーン燃焼を安定化をさせることを考えている。
【０００４】
一方、燃料の集中を低速回転かつ高負荷においてもそのまま行わせると、空気流速が高くなること及び燃料量が多くなることによってますます成層化が進み、その結果、燃焼室の一部が過濃（オーバリッチ）となり、極端な場合は黒煙が発生するおそれがある。
【０００５】
本発明は、上記問題点に鑑みてなされたもので、低負荷域での燃焼安定性の確保並びに高負荷域でのオーバリッチの解消を達成できる４サイクルエンジンの燃料噴射制御装置を提供することを目的としている。
【０００６】
【課題を解決するための手段】
本発明は、点火プラグが略中央に配置された燃焼室と、該燃焼室に開口する吸気弁開口に連通する吸気通路と、上記吸気弁開口を開閉する吸気弁と、上記吸気弁開口から上記燃焼室に向けて燃料を噴射する燃料噴射弁と、上記吸気通路を吸入空気量の少ない運転域で閉じ、吸入空気量の多い運転域で開く吸気制御弁とを備えた４サイクルエンジンにおいて、上記吸気制御弁は、丸棒の一部を切り欠くことにより弁部を形成してなり、吸気通路の底部に形成された弁穴内に配置され、吸気通路内面と面一となる全開位置と、吸気通路底壁側を絞り込む全閉位置との間で回動可能となっており、上記吸気制御弁が閉じかつ低負荷の場合には、上記燃料噴射弁による燃料噴射が少なくとも吸気弁が開いているときに行われるよう、また上記吸気制御弁が閉じかつ高負荷の場合には、上記燃料噴射弁による燃料噴射が吸気弁が開いているとき及びそ前行程にて閉じているときの両方において行われるよう、該燃料噴射弁を駆動制御する燃料噴射制御手段を備え、吸気通路の上記吸気制御弁より下流側に整流部材を配設し、該整流部材は、上記吸気通路の略中心線に沿って延び、その上流端部は全閉位置に位置する上記吸気制御弁の弁部の上方に位置し、その下流端部は吸気弁より点火プラグ側でかつ吸気弁開口の直近上流側に位置し、さらに上記上流端部と下流端部との間の部分でかつカム軸方向両端部は吸気通路の内面に当接しており、上記燃料噴射弁を上記整流部材より上流側に配設したことを特徴としている。
【０００７】
【作用】
本発明では、低負荷かつ低速回転時には、吸気制御弁が吸気通路断面積を減少させるとともに、燃料噴射制御手段の駆動制御により、燃料噴射弁による燃料噴射が少なくとも吸気弁が開いているときに行われる。この結果、リーン燃焼に対応して燃料供給量を少なく設定しながら点火プラグ近辺に燃料が存在した状態をつくることができ、燃料の着火が容易になる。これにより、成層化燃焼を行わせることができ、リーン燃焼時の燃焼安定性を確保できる。
【０００８】
また高負荷かつ低速回転時には、吸気制御弁が吸気通路断面積を減少させるとともに、燃料噴射制御手段の駆動制御により、燃料噴射弁による燃料噴射が、吸気弁が開いているとき及びその前行程（排気行程）にて閉じているときの両方において行われる。即ち燃料の一部は排気行程にて吸気弁が閉じているとき噴射されることにより均一な混合気となり、また残りの燃料は吸気弁が開いているとき噴射されることにより、点火プラグ近辺に集中して供給される。その結果全ての燃料を吸気行程で噴射する場合に生じる燃料の過度の集中を回避でき、空気利用率を向上して、オーバリッチを解消でき、成層化時に発生しやすい過濃による黒煙の発生を抑制できるとともに、高馬力を得ることができる。
【０００９】
【実施例】
以下、本発明の実施例を添付図面に基づいて説明する。
図１及び図２は本発明の一実施例による４サイクルエンジンの燃料噴射制御装置を説明するための図である。
【００１０】
図において、１は水冷式４サイクル並列４気筒４バルブエンジンであり、これは、クランクケース２上にシリンダブロック３，シリンダヘッド４を積層してヘッドボルトで締結し、該シリンダヘッド４の上側合面にヘッドカバー５を装着した構造のものである。上記シリンダブロック３に形成されたシリンダボア３ａ内にピストン７が摺動自在に挿入配置されており、該ピストン７はコンロッド８でクランク軸（図示せず）に連結されている。
【００１１】
上記シリンダヘッド４のシリンダブロック３側の下側合面４ａには燃焼室を構成する燃焼凹部４ｂが凹設されている。該燃焼凹部４ｂの中央には点火プラグ９が螺挿されており、また該点火プラグ９の周囲には吸気弁開口４ｃ，排気弁開口４ｄがそれぞれ２つずつ開口している。なお、上記各開口４ｃ，４ｄは、これらの部分に装着された概ねリング状のバルブシート２８，２９の各開口によってそれぞれ形成されている。また、各排気弁開口４ｄには排気弁１０のバルブヘッド１０ａが、各吸気弁開口４ｃには吸気弁１１のバルブヘッド１１ａがそれぞれ各開口を開閉可能に、すなわち上記バルブシート２８，２９の各シート面に当接可能に配置されている。この排気，吸気弁１０，１１のバルブステム１０ｂ，１１ｂはカム軸方向に見て所定の挟み角をなすように気筒軸方向に斜め上方に延びており、その上端には排気，吸気リフタ１２，１３がそれぞれ装着されている。また該各リフタ１２，１３上には、これを押圧駆動する排気，吸気カム軸１４，１５が気筒軸と直角方向に向けて、かつ互いに平行に配置されている。
【００１２】
上記２つの排気弁開口４ｄは二股状の排気通路１６でシリンダヘッド４の前壁４ｆ側に導出されており、該排気通路１６の壁面開口１６ａには図示しない排気管が接続されている。上記各吸気弁開口４ｃはそれぞれ吸気通路１７によりシリンダヘッド４の後壁４ｇ側に導出されている。この２本の吸気通路１７は気筒軸方向に見るとカム軸と直角方向に直線的に延びており、またカム軸方向に見ると、上記吸気弁開口４ｃからシリンダ後壁４ｇ側に円弧状に屈曲した後、略直線状に延びている。また、吸気通路１７の後壁開口１７ａには、吸気マニホールド１８を介してスロットルボディ２４が接続されており、該ボディ２４内にはスロットル弁２４ａが回動可能に配設されている。
【００１３】
上記各吸気通路１７の下流側直線部１７ｂには、弁穴１７ｃがカム軸方向に貫通形成されている。この弁穴１７ｃは、シリンダヘッド締結ボルト（図示せず）より気筒軸側に配置されており、かつその軸線が該吸気通路１７の底壁表面付近に位置し、吸気通路１７内部分は略半円状に形成されており、隣接する２つの気筒用吸気通路を連通している。この弁穴１７ｃ内には、各吸気通路１７の通路断面積及び断面形状を変化させるための吸気制御弁２５が挿入配置されている。この吸気制御弁２５は、丸棒の一部を吸気通路１７の下部内面と連続面をなすように切り欠くことにより各吸気通路１７を開閉する弁部２５ａを形成してなるものであり、上記弁部２５ａが弁穴１７ｃ内に没入して吸気通路内面と面一となる全開位置と、上記弁部２５ａが吸気通路底壁面から起立して吸気通路１７を略１／２に絞り込むとともに、吸気通路断面形状をカム軸方向に細長い横長形状とする全閉位置（図１参照）との間で回動可能となっている。この場合、上記弁部２５ａの外周面が上流側に位置するように回動する。
【００１４】
上記各吸気通路１７の天壁部分にはそれぞれ燃料噴射弁２６が装着されている。該各燃料噴射弁２６の噴射ノズルは、シリンダ後壁４ｇ内に形成された噴射孔２６ａを介して吸気制御弁２５の上端部、すなわち吸気通路面積の最も絞られた部分から吸気弁１１のバルブヘッド１１ａの裏面に渡る部分に向いている。従って噴射された燃料の一部は吸気制御弁２５及び後述する整流部材３０に当たることとなる。
【００１５】
上記吸気通路１７の吸気制御弁２５より下流側には整流部材３０が設けられている。この整流部材３０は吸気通路１７の略中心線に沿って延びており、その上流端部は、全閉位置に位置する上記吸気制御弁２５の弁部２５ａの上方に位置している。またその下流端部は、吸気弁１１より点火プラグ９側に位置し、かつ吸気弁開口４ｃの直近上流側に位置している。
【００１６】
また、このエンジンには制御装置４０が設けられている。制御装置４０には、スロットル開度センサ４１からのスロットルバルブ２４ａの開度信号ａ、カム角度センサ４２からのカム軸１５のカム角度信号ｂ、及び回転センサ４３からのエンジン回転速度信号ｃがそれぞれ入力され、各入力信号に基づいて燃料噴射弁２６を後述のように制御する。
【００１７】
次に本実施例の動作について説明する。
低速回転，低負荷時のように吸入空気量の少ない運転領域においては、上記制御装置４０からの制御信号（図示せず）によって、上記吸気制御弁２５が図１に示す全閉位置に回動する。すると、吸気制御弁２５の弁部２５ａによって上記吸気通路１７の底壁側が絞り込まれ、吸気が整流部材３０によって吸気通路１７の天壁側に偏るよう整流されつつ流れる。この結果、吸気が燃焼室内に高速で方向性をもって吹き込まれ、図１に矢印で示すようにタンブルが発生する。
【００１８】
この場合において上記制御装置４０からの制御信号Ａによって上記燃料噴射弁２６の噴射時期が制御され、図３に示すように吸気行程において即ち上記吸気弁１１が開いた状態において燃料が噴射される。噴射された燃料は、吸気弁開口４ｃを通って点火プラグ９近辺に導入され、これによりリーン燃焼に対応した少燃料噴射量でありながら点火プラグ９近辺に燃料が集中的に存在した状態をつくることができ、燃料の着火が容易になる。この結果、成層化燃焼を行わせることができ、リーン燃焼時の燃焼安定性を確保できる。
【００１９】
また、上記低速回転時において高負荷の場合には、上記制御装置４０からの制御信号Ａによって上記燃料噴射弁２６が制御され、図３に示すように、燃料の一部が吸気弁１１が閉じているとき即ち直前の排気行程で噴射され、燃料の残りは吸気弁１１が開いているときに噴射される。このように燃料の一部が吸気弁１１が閉じているとき噴射され、次の吸気行程で均一な混合気となって燃料室に導入されるので、全ての燃料を吸気弁が閉じている間に噴射した場合に生じる過度の燃料集中を防止できる。このようにして、空気利用率を向上でき、オーバリッチを解消して成層化時に発生しやすい過濃による黒煙の発生を抑制できるとともに、高馬力を得ることができる。
【００２０】
なお、吸気制御弁２５が開いている場合は、従来と同様に、全ての燃料が直前の排気行程において噴射される。また上記実施例では２つの吸気通路のそれぞれに燃料噴射弁を設けたが、本発明では勿論２つの吸気通路に対して１つの燃料噴射弁を設けても良い。
【００２１】
【発明の効果】
以上のように本発明に係る４サイクルエンジンの燃料噴射制御装置によれば、吸気制御弁が閉じかつ低負荷の場合には、燃料噴射弁による燃料噴射が少なくとも該吸気弁が開いているときに行われるので、燃料の着火が容易になり、これにより、成層化燃焼を行わせることができ、リーン燃焼時の燃焼安定性を確保できる。
【００２２】
また、吸気制御弁が閉じかつ高負荷の場合には、燃料噴射弁による燃料噴射が吸気弁が閉じているとき及び開いているときの両方において行われるので、吸気弁が閉じているとき噴射された燃料が均一な混合気となることからオーバリッチを解消でき、過濃による黒煙の発生を抑制できるとともに、高馬力を得ることができる。
【図面の簡単な説明】
【図１】本発明の一実施例による制御装置を備えた４サイクルエンジンの断面側面図である。
【図２】上記実施例における燃料噴射弁の配置状態を示す平面図である。
【図３】上記実施例装置の制御動作を説明するための図である。
【符号の説明】
１ エンジン
３ シリンダブロック
４ シリンダヘッド
４ｂ 燃焼凹部
１０ 排気弁
１１ 吸気弁
２６ 燃料噴射弁
４０ 制御装置[0001]
[Industrial application fields]
The present invention relates to a fuel injection control device for a four-cycle engine, and more particularly to a device capable of ensuring combustion stability in a low load region and further eliminating overrich in a high load region.
[0002]
[Prior art]
A four-cycle engine having a fuel injection valve that injects fuel into a combustion chamber and an intake control valve that variably controls an intake passage cross-sectional area has been proposed. In this type of engine, the fuel injection by the normal fuel injection valve is performed once each toward the back surface of the valve head of the intake valve in each exhaust stroke when the intake valve is closed. The fuel injected into the intake valve in the exhaust stroke is vaporized, and the air-fuel mixture is introduced into the combustion chamber in the intake stroke. On the other hand, when the intake amount is small, such as during low-speed rotation, the intake control valve reduces the intake passage cross-sectional area. As a result, the flow rate of the intake air is increased, the direction of the intake air is generated, and lean combustion (lean air-fuel ratio combustion) can be stabilized.
[0003]
[Problems to be solved by the invention]
However, in the above-described engine, when the engine rotates at a low speed and has a low load, the fuel injection amount decreases, and the combustion state may become unstable. In view of this, the present inventor considers that the lean combustion is stabilized by stratifying the fuel in the vicinity of the spark plug when the load is low.
[0004]
On the other hand, if the fuel is concentrated even at a low speed and a high load, the stratification proceeds more and more as the air flow rate increases and the amount of fuel increases. In extreme cases, black smoke may be generated.
[0005]
The present invention has been made in view of the above problems, and provides a fuel injection control device for a four-cycle engine capable of ensuring combustion stability in a low load region and eliminating overrich in a high load region. It is an object.
[0006]
[Means for Solving the Problems]
The present invention includes a combustion chamber in which a spark plug is disposed substantially in the center, an intake passage communicating with an intake valve opening that opens to the combustion chamber, an intake valve that opens and closes the intake valve opening, and the intake valve opening a fuel injection valve for injecting fuel into the combustion chamber, closing the intake passage in a small operation range of the intake air amount, the 4-cycle engine having an intake control valve opening at high operating range of the intake air amount, the The intake control valve forms a valve portion by cutting out a part of a round bar, and is disposed in a valve hole formed in the bottom portion of the intake passage. When the intake control valve is closed and the load is low, the fuel injection by the fuel injection valve is at least open. As sometimes done, also above intake control When the engine is closed and the load is high, the fuel injection valve is driven and controlled so that fuel injection by the fuel injection valve is performed both when the intake valve is open and when it is closed in the previous stroke. Provided with fuel injection control means, and a rectifying member is disposed downstream of the intake control valve in the intake passage, the rectifying member extends along a substantially center line of the intake passage, and an upstream end thereof is in a fully closed position. Is located above the valve portion of the intake control valve located at the downstream end portion of the intake control valve is located closer to the ignition plug side than the intake valve and immediately upstream of the intake valve opening, and further includes the upstream end portion and the downstream end portion. And both ends in the cam shaft direction are in contact with the inner surface of the intake passage, and the fuel injection valve is disposed upstream of the rectifying member.
[0007]
[Action]
In the present invention, during low load and low speed rotation, the intake control valve reduces the intake passage cross-sectional area, and the fuel injection by the fuel injection control means is performed at least when the intake valve is open by the drive control of the fuel injection control means. Is called. As a result, it is possible to create a state in which fuel is present in the vicinity of the spark plug while setting the amount of fuel supply corresponding to lean combustion, and fuel ignition is facilitated. Thereby, stratified combustion can be performed and the combustion stability at the time of lean combustion can be ensured.
[0008]
In addition, at the time of high load and low speed rotation, the intake control valve reduces the intake passage cross-sectional area, and the fuel injection control means drives the fuel injection by the fuel injection valve when the intake valve is open and its previous stroke ( It is performed both when closed in the exhaust stroke). In other words, a part of the fuel is injected when the intake valve is closed during the exhaust stroke, resulting in a uniform mixture, and the remaining fuel is injected when the intake valve is open, so that Concentrated supply. As a result, excessive concentration of fuel that occurs when all the fuel is injected in the intake stroke can be avoided, air utilization can be improved, over-rich can be eliminated, and black smoke is generated due to over-concentration that tends to occur during stratification. Can be suppressed and high horsepower can be obtained.
[0009]
【Example】
Embodiments of the present invention will be described below with reference to the accompanying drawings.
1 and 2 are views for explaining a fuel injection control device for a four-cycle engine according to an embodiment of the present invention.
[0010]
In the figure, reference numeral 1 denotes a water-cooled four-cycle parallel four-cylinder four-valve engine, in which a cylinder block 3 and a cylinder head 4 are stacked on a crankcase 2 and fastened with a head bolt. The head cover 5 is mounted on the surface. A piston 7 is slidably inserted in a cylinder bore 3 a formed in the cylinder block 3, and the piston 7 is connected to a crankshaft (not shown) by a connecting rod 8.
[0011]
A combustion recess 4b that constitutes a combustion chamber is formed in the lower joint surface 4a of the cylinder head 4 on the cylinder block 3 side. A spark plug 9 is screwed into the center of the combustion recess 4b, and two intake valve openings 4c and two exhaust valve openings 4d are opened around the spark plug 9, respectively. The openings 4c and 4d are formed by the openings of generally ring-shaped valve seats 28 and 29 attached to these portions. Further, the valve head 10a of the exhaust valve 10 can be opened and closed by each exhaust valve opening 4d, and the valve head 11a of the intake valve 11 can be opened and closed by each intake valve opening 4c, that is, each of the valve seats 28 and 29 can be opened and closed. It arrange | positions so that contact | abutting to a sheet | seat surface is possible. The valve stems 10b and 11b of the exhaust and intake valves 10 and 11 extend obliquely upward in the cylinder axial direction so as to form a predetermined sandwich angle when viewed in the cam shaft direction, and the exhaust and intake lifter 12 and 13 are respectively mounted. On each of the lifters 12 and 13, exhaust and intake camshafts 14 and 15 for pressing and driving the lifters 12 and 13 are arranged in a direction perpendicular to the cylinder shaft and parallel to each other.
[0012]
The two exhaust valve openings 4d are led out to the front wall 4f side of the cylinder head 4 by a bifurcated exhaust passage 16, and an exhaust pipe (not shown) is connected to the wall surface opening 16a of the exhaust passage 16. The intake valve openings 4c are led out to the rear wall 4g side of the cylinder head 4 by intake passages 17, respectively. The two intake passages 17 extend linearly in a direction perpendicular to the cam shaft when viewed in the cylinder axis direction, and when viewed in the cam axis direction, the two intake passages 17 have an arc shape from the intake valve opening 4c toward the cylinder rear wall 4g. After bending, it extends substantially linearly. A throttle body 24 is connected to the rear wall opening 17a of the intake passage 17 via an intake manifold 18, and a throttle valve 24a is rotatably disposed in the body 24.
[0013]
A valve hole 17c is formed through the downstream straight portion 17b of each intake passage 17 in the camshaft direction. This valve hole 17c is arranged on the cylinder shaft side from a cylinder head fastening bolt (not shown), and its axis is located near the bottom wall surface of the intake passage 17, and the inner portion of the intake passage 17 is substantially half. It is formed in a circular shape and communicates with two adjacent cylinder intake passages. An intake control valve 25 for changing the passage cross-sectional area and the cross-sectional shape of each intake passage 17 is inserted into the valve hole 17c. The intake control valve 25 is formed by forming a valve portion 25 a that opens and closes each intake passage 17 by cutting out a part of a round bar so as to form a continuous surface with the lower inner surface of the intake passage 17. The valve portion 25a is inserted into the valve hole 17c so as to be flush with the inner surface of the intake passage, and the valve portion 25a rises from the bottom surface of the intake passage to narrow the intake passage 17 to approximately ½. It can be rotated between a fully closed position (see FIG. 1) in which the passage cross-sectional shape is a horizontally long shape elongated in the cam shaft direction. In this case, it rotates so that the outer peripheral surface of the said valve part 25a may be located in an upstream.
[0014]
A fuel injection valve 26 is mounted on the top wall portion of each intake passage 17. The injection nozzle of each fuel injection valve 26 is a valve of the intake valve 11 from the upper end portion of the intake control valve 25, that is, the most narrowed portion of the intake passage area through an injection hole 26a formed in the cylinder rear wall 4g. It is suitable for the part across the back surface of the head 11a. Therefore, a part of the injected fuel hits the intake control valve 25 and a rectifying member 30 described later.
[0015]
A rectifying member 30 is provided downstream of the intake control valve 25 in the intake passage 17. The flow regulating member 30 extends along a substantially center line of the intake passage 17, and an upstream end portion thereof is located above the valve portion 25a of the intake control valve 25 located at the fully closed position. Further, the downstream end thereof is located closer to the spark plug 9 than the intake valve 11 and is located immediately upstream of the intake valve opening 4c.
[0016]
The engine 40 is provided with a control device 40. The control device 40 includes an opening degree signal a of the throttle valve 24a from the throttle opening degree sensor 41, a cam angle signal b of the camshaft 15 from the cam angle sensor 42, and an engine speed signal c from the rotation sensor 43. Based on each input signal, the fuel injection valve 26 is controlled as described later.
[0017]
Next, the operation of this embodiment will be described.
In an operation region where the intake air amount is small, such as during low speed rotation and low load, the intake control valve 25 is rotated to the fully closed position shown in FIG. 1 by a control signal (not shown) from the control device 40. To do. Then, the bottom wall side of the intake passage 17 is throttled by the valve portion 25a of the intake control valve 25, and the intake air flows while being rectified by the rectifying member 30 so as to be biased toward the top wall side of the intake passage 17. As a result, the intake air is blown into the combustion chamber at high speed and with directivity, and tumble occurs as shown by arrows in FIG.
[0018]
In this case, the injection timing of the fuel injection valve 26 is controlled by the control signal A from the control device 40, and fuel is injected during the intake stroke, that is, when the intake valve 11 is open as shown in FIG. The injected fuel is introduced into the vicinity of the spark plug 9 through the intake valve opening 4c, thereby creating a state where the fuel is concentrated in the vicinity of the spark plug 9 while being a small fuel injection amount corresponding to lean combustion. This makes it easy to ignite the fuel. As a result, stratified combustion can be performed, and combustion stability during lean combustion can be ensured.
[0019]
Further, in the case of a high load at the time of the low speed rotation, the fuel injection valve 26 is controlled by the control signal A from the control device 40, and a part of the fuel closes the intake valve 11 as shown in FIG. That is, in the previous exhaust stroke, the remainder of the fuel is injected when the intake valve 11 is open. In this way, a part of the fuel is injected when the intake valve 11 is closed, and is introduced into the fuel chamber as a uniform air-fuel mixture in the next intake stroke, so that all the fuel is removed while the intake valve is closed. It is possible to prevent excessive fuel concentration that occurs when the fuel is injected into the tank. In this way, the air utilization rate can be improved, over-rich can be eliminated, the generation of black smoke due to over-concentration that tends to occur during stratification can be suppressed, and high horsepower can be obtained.
[0020]
When the intake control valve 25 is open, all the fuel is injected in the immediately preceding exhaust stroke as in the conventional case. In the above embodiment, the fuel injection valve is provided in each of the two intake passages. However, in the present invention, of course, one fuel injection valve may be provided for the two intake passages.
[0021]
【The invention's effect】
As described above, according to the fuel injection control device for a four-cycle engine according to the present invention, when the intake control valve is closed and the load is low, the fuel injection by the fuel injection valve is at least when the intake valve is open. Therefore, the ignition of the fuel is facilitated, whereby stratified combustion can be performed, and combustion stability during lean combustion can be ensured.
[0022]
In addition, when the intake control valve is closed and the load is high, fuel injection by the fuel injection valve is performed both when the intake valve is closed and when it is open, so that the injection is performed when the intake valve is closed. Since the fuel becomes a uniform air-fuel mixture, it is possible to eliminate over-rich conditions, suppress the generation of black smoke due to over-concentration, and obtain high horsepower.
[Brief description of the drawings]
FIG. 1 is a cross-sectional side view of a four-cycle engine including a control device according to an embodiment of the present invention.
FIG. 2 is a plan view showing an arrangement state of fuel injection valves in the embodiment.
FIG. 3 is a diagram for explaining a control operation of the apparatus according to the embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Engine 3 Cylinder block 4 Cylinder head 4b Combustion recessed part 10 Exhaust valve 11 Intake valve 26 Fuel injection valve 40 Control apparatus

Claims (1)

点火プラグが略中央に配置された燃焼室と、該燃焼室に開口する吸気弁開口に連通する吸気通路と、上記吸気弁開口を開閉する吸気弁と、上記吸気弁開口から上記燃焼室に向けて燃料を噴射する燃料噴射弁と、上記吸気通路を吸入空気量の少ない運転域で閉じ、吸入空気量の多い運転域で開く吸気制御弁とを備えた４サイクルエンジンにおいて、上記吸気制御弁は、丸棒の一部を切り欠くことにより弁部を形成してなり、吸気通路の底部に形成された弁穴内に配置され、吸気通路内面と面一となる全開位置と、吸気通路底壁側を絞り込む全閉位置との間で回動可能となっており、上記吸気制御弁が閉じかつ低負荷の場合には、上記燃料噴射弁による燃料噴射が少なくとも吸気弁が開いているときに行われるよう、また上記吸気制御弁が閉じかつ高負荷の場合には、上記燃料噴射弁による燃料噴射が吸気弁が開いているとき及びそ前行程にて閉じているときの両方において行われるよう、該燃料噴射弁を駆動制御する燃料噴射制御手段を備え、吸気通路の上記吸気制御弁より下流側に整流部材を配設し、該整流部材は、上記吸気通路の略中心線に沿って延び、その上流端部は全閉位置に位置する上記吸気制御弁の弁部の上方に位置し、その下流端部は吸気弁より点火プラグ側でかつ吸気弁開口の直近上流側に位置し、さらに上記上流端部と下流端部との間の部分でかつカム軸方向両端部は吸気通路の内面に当接しており、上記燃料噴射弁を上記整流部材より上流側に配設したことを特徴とする４サイクルエンジンの燃料噴射制御装置。 A combustion chamber in which a spark plug is disposed substantially in the center, an intake passage communicating with the intake valve opening that opens to the combustion chamber, an intake valve that opens and closes the intake valve opening, and the intake valve opening toward the combustion chamber In a four-cycle engine having a fuel injection valve that injects fuel and an intake control valve that closes the intake passage in an operation region where the intake air amount is small and opens in an operation region where the intake air amount is large, the intake control valve is The valve portion is formed by cutting out a part of the round bar, and is disposed in the valve hole formed in the bottom portion of the intake passage. The fully open position is flush with the intake passage inner surface, and the intake passage bottom wall side When the intake control valve is closed and the load is low, fuel injection by the fuel injection valve is performed at least when the intake valve is open. Whether the intake control valve is closed In the case of a high load, fuel injection control that drives and controls the fuel injection valve so that fuel injection by the fuel injection valve is performed both when the intake valve is open and when it is closed in the previous stroke. And a rectifying member is disposed downstream of the intake control valve in the intake passage, the rectifying member extends along a substantially center line of the intake passage, and an upstream end portion thereof is located at a fully closed position. Located above the valve portion of the intake control valve, the downstream end portion thereof is located on the ignition plug side of the intake valve and immediately upstream of the intake valve opening, and further between the upstream end portion and the downstream end portion. A fuel injection control device for a four-cycle engine, wherein both ends of the camshaft direction are in contact with the inner surface of the intake passage, and the fuel injection valve is disposed upstream of the rectifying member.
JP26385192A 1992-10-01 1992-10-01 4-cycle engine fuel injection control system Expired - Fee Related JP3727357B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP26385192A JP3727357B2 (en) 1992-10-01 1992-10-01 4-cycle engine fuel injection control system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP26385192A JP3727357B2 (en) 1992-10-01 1992-10-01 4-cycle engine fuel injection control system

Publications (2)

Publication Number Publication Date
JPH06117297A JPH06117297A (en) 1994-04-26
JP3727357B2 true JP3727357B2 (en) 2005-12-14

Family

ID=17395114

Family Applications (1)

Application Number Title Priority Date Filing Date
JP26385192A Expired - Fee Related JP3727357B2 (en) 1992-10-01 1992-10-01 4-cycle engine fuel injection control system

Country Status (1)

Country Link
JP (1) JP3727357B2 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003239749A (en) * 2002-02-19 2003-08-27 Nissan Motor Co Ltd Fuel supply device for internal combustion engine

Also Published As

Publication number Publication date
JPH06117297A (en) 1994-04-26

Similar Documents

Publication Publication Date Title
USRE36500E (en) Internal combustion engine
US5937821A (en) Control apparatus for an in-cylinder injection type internal combustion engine
US5735240A (en) Direct injected engine
JPH0821342A (en) Fuel injection type engine
JPH07119592A (en) Engine with twin valve of fuel injection type
US20050081820A1 (en) Direct injection internal combustion engine
JP3727357B2 (en) 4-cycle engine fuel injection control system
US5720259A (en) Fuel injected multi-valve engine
US6367444B1 (en) Cylinder head for direct injected engine
JPS6282222A (en) Combustion chamber structure in engine
JPH09317476A (en) Cylinder fuel injection type engine
JPS61215422A (en) Multi-intake valve engine
JP3612875B2 (en) In-cylinder injection engine
JP3506769B2 (en) Engine intake control device
JP3639048B2 (en) In-cylinder fuel injection engine
JP3320805B2 (en) 4-cycle engine intake system
JP3012023B2 (en) Engine intake control device
JP3279600B2 (en) Engine intake control device
JP3264748B2 (en) Intake control structure for two-valve engine
JP3323283B2 (en) Intake device for 4-cycle internal combustion engine
JP3457751B2 (en) 4-cycle engine intake control system
JPH03264768A (en) Intake device of multivalve engine
JPH0658105B2 (en) Engine intake system
JPS6020574B2 (en) Exhaust gas recirculation device for multi-cylinder internal combustion engines
JPH03160113A (en) Intake device of multi-valve engine

Legal Events

Date Code Title Description
A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20040309

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20040507

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20050927

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20050928

R150 Certificate of patent or registration of utility model

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20111007

Year of fee payment: 6

LAPS Cancellation because of no payment of annual fees