JPH03246362A - Egr negative pressure generation control method and egr control device for diesel engine - Google Patents
Egr negative pressure generation control method and egr control device for diesel engineInfo
- Publication number
- JPH03246362A JPH03246362A JP2043689A JP4368990A JPH03246362A JP H03246362 A JPH03246362 A JP H03246362A JP 2043689 A JP2043689 A JP 2043689A JP 4368990 A JP4368990 A JP 4368990A JP H03246362 A JPH03246362 A JP H03246362A
- Authority
- JP
- Japan
- Prior art keywords
- valve
- negative pressure
- egr
- pressure generation
- passage
- 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.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims description 11
- 238000011144 upstream manufacturing Methods 0.000 claims abstract description 7
- 238000010586 diagram Methods 0.000 description 6
- 238000005516 engineering process Methods 0.000 description 3
- 239000000498 cooling water Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000010792 warming Methods 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B3/00—Engines characterised by air compression and subsequent fuel addition
- F02B3/06—Engines characterised by air compression and subsequent fuel addition with compression ignition
Landscapes
- Exhaust-Gas Circulating Devices (AREA)
- Control Of Throttle Valves Provided In The Intake System Or In The Exhaust System (AREA)
- Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
- Combined Controls Of Internal Combustion Engines (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、ディーゼルエンジンのＥＧＲ（排気ガス再循
環）制御装置に係り、さらに詳細には、エンジン吸気通
路に弁の開閉制御により負圧を発生させ、この負圧によ
りエンジンの排気ガスを還流通路を通して吸気系に導く
方式の負圧発生制御法及びこれを利用したＥＧＲ制御装
置に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an EGR (exhaust gas recirculation) control device for a diesel engine, and more specifically, to a system for applying negative pressure to an engine intake passage by controlling the opening and closing of a valve. The present invention relates to a negative pressure generation control method in which engine exhaust gas is guided to the intake system through a recirculation passage using the negative pressure, and an EGR control device using the same.
従来より、自動車等のガソリンエンジン、ディーゼルエ
ンジンの分野では、排気ガスの一部をＥＧＲ制御装置に
より吸気通路側に還元させて、エンジン気筒内の燃焼温
度を低減させ、ＮＯｘの発生量を低減させる技術が広く
知られている。Traditionally, in the field of gasoline engines and diesel engines for automobiles, a portion of exhaust gas is returned to the intake passage by an EGR control device to reduce the combustion temperature in the engine cylinder and reduce the amount of NOx generated. The technology is widely known.
このうち、ガソリンエンジンにおいては、吸気流量を制
御する絞り弁が存在するので、絞り弁の動作を利用して
、ＥＧＲ制御を行っている。例えば特開昭５３−２９４
１８号、特開昭５７−１８４４９号公報等に開示される
装置では、排気ガス還流通路に負圧ダイアフラム形流量
制御弁を配置し、一方、吸気通路には、絞り弁が全閉に
なるとその上流に位置し所定の開度以上になると絞り弁
下流に位置する開口を設け、この開口が絞り弁下流に位
置した時の負圧を前記負圧ダイアフラム形流量制御弁に
与えて、排気ガス還流通路を開き、吸気通路に排気ガス
の一部を導いている。Among these, in a gasoline engine, there is a throttle valve that controls the intake air flow rate, so EGR control is performed using the operation of the throttle valve. For example, JP-A-53-294
No. 18, Japanese Patent Application Laid-open No. 57-18449, etc., a negative pressure diaphragm type flow control valve is arranged in the exhaust gas recirculation passage, while in the intake passage, when the throttle valve is fully closed, the An opening located upstream and located downstream of the throttle valve is provided when the opening exceeds a predetermined opening degree, and this opening applies the negative pressure when located downstream of the throttle valve to the negative pressure diaphragm type flow control valve to recirculate the exhaust gas. The passage is opened and part of the exhaust gas is guided into the intake passage.
また、特開昭５９−１４７８４０号、特開昭６３−１９
２９４６号公報等に開示されるように、アイドル制御用
の吸気流量制御弁を排気ガス還流用の流量制御弁に切り
換えて使用できるようにしたものがある。なお、これら
の従来技術は、いずれも絞り弁の存在で絞り弁下流域に
負圧が発生するため、この負圧により排気ガスを吸気系
に吸引している。Also, JP-A-59-147840, JP-A-63-19
As disclosed in Japanese Patent No. 2946, etc., there is a device in which an intake flow rate control valve for idle control can be switched to a flow rate control valve for exhaust gas recirculation. Note that in all of these conventional techniques, the presence of the throttle valve generates negative pressure in the downstream region of the throttle valve, so exhaust gas is sucked into the intake system using this negative pressure.
一方、ディーゼルエンジンでは、一般に空気を流量制御
することなくエンジン気筒内に吸引し、出力制御は、気
筒内に噴射される燃料量によって行うため、ガソリンエ
ンジンのようにアクセルペダルにより連続的な吸気流量
制御を行ういわゆる本来の絞り弁は使用されていない。On the other hand, in diesel engines, air is generally sucked into the engine cylinders without flow rate control, and output control is performed by the amount of fuel injected into the cylinders. No so-called real throttle valves are used for control.
従って、従来は、吸気通路に絞り弁に類するＥＧＲ負圧
負圧発生用膜け、この弁を必要に応じて閉じる（但し開
度Ｏではなく、ある程度の開度を保つ）ことで弁下流に
負圧を発生させ、この負圧吸引力で排気ガスを排気ガス
還流通路を介して導入していた。Therefore, in the past, a membrane for generating EGR negative pressure, similar to a throttle valve, was installed in the intake passage, and this valve was closed as necessary (however, the opening was maintained at a certain degree, not at the opening degree of O), so that the valve could be opened downstream of the valve. Negative pressure was generated, and exhaust gas was introduced through the exhaust gas recirculation passage using this negative pressure suction force.
第６図にディーゼルエンジンに使用されるＥＧＲ制御装
置の従来例を示す。FIG. 6 shows a conventional example of an EGR control device used in a diesel engine.
第６図において、１はエンジン、２は排気通路、３はマ
フラー、４は吸気通路、５は吸気通路の一部をなすチャ
ンバボディ、６はエアクリーナである。In FIG. 6, 1 is an engine, 2 is an exhaust passage, 3 is a muffler, 4 is an intake passage, 5 is a chamber body forming a part of the intake passage, and 6 is an air cleaner.
チャンバボディ５の内部には、ＥＧＲ負圧発生用弁７が
弁軸８に固定され、弁軸８の一端には、回動レバー９が
装着される。レバー９は電磁ソレノイド式アクチュエー
タ１１のプランジャとロッド１０を介して連結される。Inside the chamber body 5, an EGR negative pressure generation valve 7 is fixed to a valve shaft 8, and a rotating lever 9 is attached to one end of the valve shaft 8. The lever 9 is connected to a plunger of an electromagnetic solenoid actuator 11 via a rod 10.
１２は排気ガス還流通路で、一端が排気通路２に接続さ
れ、他端が吸気通路４のＥＧＲ負圧負圧発生用尺７流域
４ａに接続され、その途中には、排気ガス導入用の弁１
３及びこれを開閉駆動させる電磁ソレノイド式アクチュ
エータ１４が配置される。Reference numeral 12 designates an exhaust gas recirculation passage, one end of which is connected to the exhaust passage 2, the other end of which is connected to the EGR negative pressure generation area 4a of the intake passage 4, and a valve for introducing exhaust gas is provided in the middle thereof. 1
3 and an electromagnetic solenoid actuator 14 for opening and closing the same.
１５は制御ユニットで、エンジン運転条件に応じてアク
チュエータ１１．１４にＥＧＲ負圧負圧発生用尺７排気
ガス導入用弁１３の開閉に関する指令信号を出力する。Reference numeral 15 denotes a control unit that outputs command signals regarding opening and closing of the exhaust gas introduction valve 13 for generating EGR negative pressure to the actuator 11.14 according to engine operating conditions.
このような構成では、ＥＧＲ負圧負圧発生用尺７定開度
に閉じると、弁７下流の吸気通路４ａに負圧が発生し、
この時に排気ガス導入用弁１３が開いて排気ガスの一部
が吸気系に導かれ、吸気と一緒に排気ガスがエンジン気
筒に供給される。In such a configuration, when the EGR negative pressure negative pressure generation valve 7 is closed to a fixed opening degree, negative pressure is generated in the intake passage 4a downstream of the valve 7,
At this time, the exhaust gas introduction valve 13 opens and a portion of the exhaust gas is introduced into the intake system, and the exhaust gas is supplied to the engine cylinders together with the intake air.
ディーゼルエンジンのＥＧＲ制御装置に関しては、例え
ば、特開昭５６−９６１４６号公報に開示されたものが
ある。この公開技術では、ＥＧＲ負圧発生用弁をバイパ
スさせた通路そのものに、排気還流用通路の一端を開口
させている・
〔発明が解決しようとする課題〕
前述した如くディーゼルエンジンのＥＧＲ制御装置では
、吸気通路にＥＧＲ負圧発生用弁を設けているが、この
ＥＧＲ負−圧発生用弁は、電磁式或いは負圧応動形ダイ
ヤフラム等のアクチュエータ（負圧はバキュームポンプ
等でつくられる）により、開か閉（ただし完全な閉では
ない）のオン・オフ制御がなされている。Regarding an EGR control device for a diesel engine, for example, there is one disclosed in Japanese Patent Laid-Open No. 56-96146. In this disclosed technology, one end of the exhaust gas recirculation passage is opened in the passage that bypasses the EGR negative pressure generation valve. [Problem to be solved by the invention] As mentioned above, the EGR control device of a diesel engine , an EGR negative pressure generation valve is provided in the intake passage, but this EGR negative pressure generation valve is operated by an actuator such as an electromagnetic type or a negative pressure responsive diaphragm (the negative pressure is generated by a vacuum pump, etc.). It is controlled to open or close (but not completely close).
その理由は、１つのアクチュエータでＥＧＲ負圧発生用
弁を精度良く中開度に保つことは、技術的及びコスト的
に困難なためである。The reason for this is that it is technically and economically difficult to accurately maintain the EGR negative pressure generation valve at a medium opening degree using one actuator.
すなわち、この種のアクチュエータは、コストの低減を
図るために、構造が簡単で単価の安いアクチュエータが
使用される。例えば、電磁式の場合には、プランジャの
磁気吸引力が戻しばねの力に勝って弁を作動させる方式
が採用される。That is, in this type of actuator, an actuator having a simple structure and a low unit price is used in order to reduce costs. For example, in the case of an electromagnetic type, a method is adopted in which the magnetic attraction force of the plunger overcomes the force of the return spring to operate the valve.
このようなアクチュエータは、電流制御等で弁が中間開
度に止まりそうであるが、実際にはばねとのバランスの
かねあいをとることが困難であり。With such an actuator, the valve is likely to remain at an intermediate opening due to current control, etc., but in reality it is difficult to balance the valve with the spring.
ばね力が必要以上に勝ったり、プランジャが磁場に近づ
くほど磁気吸引力が増加してプランジャが必要以上に吸
引されてしまう。その結果、弁開度を途中でバランス良
く保てない。The spring force may be stronger than necessary, or the magnetic attraction force increases as the plunger approaches the magnetic field, causing the plunger to be attracted more than necessary. As a result, the valve opening cannot be maintained in a well-balanced manner midway.
なお、ステップモータ等を用いてＥＧＲ負圧制御用弁を
多段に開度制御することも考えられるが。It is also conceivable to control the opening of the EGR negative pressure control valve in multiple stages using a step motor or the like.
ステップモータは、簡易な電磁弁等に較べはるかに高価
なものであり、また電磁弁に較べて大形となるで、コス
ト、搭載性の面から実用性に乏しい。Step motors are much more expensive than simple solenoid valves, etc., and are also larger than solenoid valves, making them impractical in terms of cost and mountability.
以上の理由により、従来はＥＧＲ制御弁を開か閉のいず
れかに制御する。そのため、吸気通路に発生させる負圧
発生域も１段階だけであり、ＥＧＲ制御の精度の面で改
善すべき点があった。For the above reasons, conventionally the EGR control valve is controlled to either open or close. Therefore, the negative pressure generation range generated in the intake passage is only one stage, and there is a need for improvement in terms of accuracy of EGR control.
特に、環境問題がとりざたされている今日、排気ガスの
浄化がさけばれ、全運転域に対応できるようなさらにき
め細かなＥＧＲ制御が要求されている。In particular, in today's environment where environmental issues are being talked about, purification of exhaust gas is being avoided, and more detailed EGR control that can cover the entire operating range is required.
本発明は以上の点に鑑みてなされたもので、その目的と
するところは、コスト的に安価で搭載性に優れた簡易な
アクチュエータを使用して、広範囲の運転域でＥＧＲ制
御を精度良く行い得る制御法及び装置を提供することに
ある。The present invention has been made in view of the above points, and its purpose is to accurately control EGR over a wide range of operating ranges using a simple actuator that is inexpensive and easy to install. The object of the present invention is to provide a control method and apparatus for obtaining the desired results.
第１の課題解決手段は、ＥＧＲ負圧発生制御法に関し、
その内容とするところは、
ディーゼルエンジンの吸気通路にＥＧＲ負圧発生用弁を
設け、このＥＧＲ負圧発生用弁を運転条件に応じて開閉
制御することでその弁下流域に負圧を発生させ、この負
圧によりエンジンの排気ガスを排気ガス還流通路を通し
て吸気通路に導く方式において、
前記吸気通路にＥＧＲ負圧発生用弁を迂回して該ＥＧＲ
負圧発生用弁の上下流を連通ずるバイパス通路を少なく
とも１つ設けると共に、このバイパス通路に補助弁を設
け、エンジンの運転条件に対応して前記ＥＧＲ負圧発生
用弁及び補助弁の開閉の組み合わせを変えることで、吸
気通路のＥＧＲ負圧発生用弁下流域に発生させる負圧を
多段階（２段階或いはそれ以上）に制御する。The first problem-solving means relates to an EGR negative pressure generation control method,
The content is that an EGR negative pressure generation valve is installed in the intake passage of a diesel engine, and by controlling the opening and closing of this EGR negative pressure generation valve according to operating conditions, negative pressure is generated in the downstream area of the valve. , in a system in which engine exhaust gas is guided to the intake passage through the exhaust gas recirculation passage by this negative pressure, the EGR is supplied to the intake passage by bypassing the EGR negative pressure generation valve.
At least one bypass passage communicating between the upstream and downstream sides of the negative pressure generation valve is provided, and an auxiliary valve is provided in this bypass passage, and the opening and closing of the EGR negative pressure generation valve and the auxiliary valve are controlled according to engine operating conditions. By changing the combination, the negative pressure generated in the downstream region of the EGR negative pressure generation valve in the intake passage is controlled in multiple stages (two stages or more).
第２の課題解決手段は、第１の課題解決手段の制御法を
利用したＥＧＲ制御装置に係り、その構成を、第１図の
実施例の符号を引用して説明すると、
ディーゼルエンジンの吸気通路４の開閉を行うＥＧＲ負
圧負圧発生用弁圧ＥＧＲ負圧負圧発生用弁圧動するアク
チュエータ１１と、排気通路２と吸気通路４のＥＧＲ負
圧発生用弁下流４ａとを連通させる排気ガス還流通路１
２と、排気ガス還流通路１２の開閉を行う排気ガス導入
用弁１３と、排気ガス導入用弁１３を即動するアクチュ
エータ１４とを備えた装置において、
吸気通路４にＥＧＲ負圧負圧発生用弁圧回してＥＧＲ負
圧負圧発生用弁圧下流を連通させるバイパス通路１６を
少なくとも１つ設け、
このバイパス通路１６の開閉を行う補助弁１８と、補助
弁１８を駆動するアクチュエータ１９と、エンジンの運
転状態を検出して、ＥＧＲ負圧負圧発生用弁圧助弁１８
及び排気ガス導入用弁１３の各アクチュエータ１１，１
９．１４に弁開閉指令信号を送る制御系で、予めエンジ
ン運転条件に対応させてＥＧＲ負圧負圧発生用弁圧助弁
１８及び排気ガス導入用弁１３の開閉の組み合わせパタ
ーンが設定しである制御手段１５Ａとを備えてなる。The second problem-solving means relates to an EGR control device that utilizes the control method of the first problem-solving means, and its configuration will be described by referring to the reference numerals of the embodiment shown in FIG. 1: An intake passage of a diesel engine. EGR negative pressure that opens and closes the EGR negative pressure generating valve pressure. Gas reflux passage 1
2, an exhaust gas introduction valve 13 that opens and closes the exhaust gas recirculation passage 12, and an actuator 14 that immediately operates the exhaust gas introduction valve 13. At least one bypass passage 16 is provided to communicate the downstream valve pressure for generating EGR negative pressure by turning the valve pressure, and an auxiliary valve 18 that opens and closes the bypass passage 16, an actuator 19 that drives the auxiliary valve 18, and an engine. detects the operating state of the EGR negative pressure negative pressure generation valve pressure auxiliary valve 18.
and each actuator 11, 1 of the exhaust gas introduction valve 13
In the control system that sends the valve opening/closing command signal to 9.14, a combination pattern of opening and closing of the EGR negative pressure generation valve pressure assist valve 18 and the exhaust gas introduction valve 13 can be set in advance in accordance with the engine operating conditions. A certain control means 15A is provided.
第１の課題解決手段によれば、吸気通路に設けたＥＧＲ
制御弁とこれを迂回するバイパス通路に設けた補助弁の
開閉の組み合わせパターンを、最少限次のように変える
ことができる。According to the first problem solving means, the EGR installed in the intake passage
The combination pattern of opening and closing of the control valve and the auxiliary valve provided in the bypass passage that bypasses the control valve can be changed at least as follows.
第１には、ＥＧＲ負圧負圧発生用量補助弁の双方を開と
する組み合わせである。この時には、ＥＧＲ負圧負圧発
生用量流域は大気圧となる。The first is a combination in which both EGR negative pressure generation and quantity auxiliary valves are opened. At this time, the EGR negative pressure generation area becomes atmospheric pressure.
また、ＥＧＲ負圧負圧発生用量、補助弁を閉とする組み
合わせの場合にも、吸気通路ＥＧＲ負圧発生用弁の下流
ははゾ大気圧となる。Further, even in the case of a combination of the EGR negative pressure generation amount and the auxiliary valve being closed, the downstream side of the intake passage EGR negative pressure generation valve becomes atmospheric pressure.
第２には、ＥＧＲ負圧負圧発生用量閉じ（但し、ある一
定開度が保たれる）、補助弁を開とする組み合わせであ
る。この時には、吸気通路はＥＧＲ負圧負圧発生用量り
絞られ、ＥＧＲ負圧負圧発生用量流に負圧が発生する。The second is a combination in which the EGR negative pressure negative pressure generation amount is closed (however, a certain degree of opening is maintained) and the auxiliary valve is opened. At this time, the intake passage is restricted in the amount of EGR negative pressure generated, and negative pressure is generated in the EGR negative pressure generation flow.
この場合の吸気は、絞られた吸気通路とバイパス通路を
流れる。In this case, the intake air flows through the restricted intake passage and the bypass passage.
第３に、ＥＧＲ負圧負圧発生用量じ、補助弁も閉とする
組み合わせである。この時には、吸気通路はＥＧＲ負圧
負圧発生用量り絞られ、さらにバイパス通路も閉じであ
るので、ＥＧＲ負圧負圧発生用量流に上記第２のパター
ンよりもさらに高い負圧（最大負圧）が発生する。Third, there is a combination in which the EGR negative pressure and the auxiliary valve are also closed. At this time, the intake passage is narrowed down to the amount of EGR negative pressure generated, and the bypass passage is also closed, so the EGR negative pressure generation flow has a higher negative pressure (maximum negative pressure) than in the second pattern. ) occurs.
この時の吸気は、絞られた吸気通路を流れる。At this time, the intake air flows through the narrowed intake passage.
以上のようにすれば、バイパス通路を１つとした場合に
は、例えば第５図に示すように、ＥＧＲ負圧負圧発生用
量流域の発生負圧を少なくとも２段階に制御することが
できる。また、その他に前記第１の組み合わせの状態を
加えることで、ＥＧＲ負圧負圧発生子弁下流域態を少な
くとも３種の圧力レベルに設定できる。In the above manner, when there is one bypass passage, the negative pressure generated in the EGR negative pressure generation area can be controlled in at least two stages, as shown in FIG. 5, for example. Furthermore, by adding the first combination of states to the above, the EGR negative pressure generator valve downstream state can be set to at least three different pressure levels.
さらに、バイパス通路を複数配設し各バイパス通路に補
助弁を設けた場合には、これらのバイパス通路の数だけ
順に通路を開閉できるので、さらに多段階に発生負圧を
制御することが可能となる。Furthermore, if multiple bypass passages are provided and each bypass passage is provided with an auxiliary valve, the passages can be opened and closed in sequence by the number of bypass passages, making it possible to control the generated negative pressure in even more stages. Become.
本制御法によれば、従来よりもＥＧＲ負圧負圧発生子弁
下流域生負圧をより一層段階的に制御できるので、その
分排気ガスの導入量を変えることができ、広範囲の運転
域にわたるＥＧＲ制御を可能にする。According to this control method, the negative pressure generated downstream of the EGR negative pressure generator valve can be controlled in a more stepwise manner than before, so the amount of exhaust gas introduced can be changed correspondingly, and a wide range of operation can be achieved. Enables comprehensive EGR control.
第２の課題解決手段については、実施例に詳述したので
、これを参照されたい。The second problem-solving means is described in detail in Examples, so please refer to this.
本発明の一実施例を第１図〜第５図により説明する。 An embodiment of the present invention will be described with reference to FIGS. 1 to 5.
第１図は、本発明の実施例たるＥＧＲ制御装置の説明図
で１図中、第６図の従来例と同一符号は同−或いは共通
する要素を示す。FIG. 1 is an explanatory diagram of an EGR control device according to an embodiment of the present invention. In FIG. 1, the same reference numerals as in the conventional example of FIG. 6 indicate the same or common elements.
本実施例では、吸気通路４にＥＧＲ負圧負圧発生用弁圧
け、排気ガス還流通路１２に排気ガス導入用弁１３を設
けるほかに、次のような要素が加えである。In this embodiment, in addition to providing an EGR negative pressure generation valve in the intake passage 4 and an exhaust gas introduction valve 13 in the exhaust gas recirculation passage 12, the following elements are added.
吸気通路４のチャンバボディ５の側壁には、ＥＧＲ負圧
負圧発生用弁圧回して弁７上下流を連通させるバイパス
通路１６が配設される。バイパス通路１６は、チャンバ
ボディ５と一体成形するか、或いはフレキシブルホース
等の管体で別体に形成し、これをチャンバボディに接続
してもよい。A bypass passage 16 is disposed on the side wall of the chamber body 5 of the intake passage 4 to circulate the pressure of the EGR negative pressure generation valve and communicate the upstream and downstream sides of the valve 7. The bypass passage 16 may be formed integrally with the chamber body 5, or may be formed separately from a tube such as a flexible hose and connected to the chamber body.
バイパス通路１６の途中には、通路１６の開閉を行うた
めの補助弁１８が配置される。補助弁１８は電磁式のア
クチュエータ１９により即動され、電磁弁として機能す
る。An auxiliary valve 18 for opening and closing the passage 16 is arranged in the middle of the bypass passage 16. The auxiliary valve 18 is immediately actuated by an electromagnetic actuator 19 and functions as a solenoid valve.
１７は、バイパス通路４の補助弁の下流に形成した絞り
で、絞り１７は、ＥＧＲ負圧負圧発生用尺７の時に補助
弁１８を開いた時でも、ＥＧＲ負圧発生用弁７下流が僅
かながら多少の負圧を維持できるように配慮して配置さ
れる。この絞り１７は、一定或いは可変の穴径の絞りで
あってもよい。Reference numeral 17 denotes a throttle formed downstream of the auxiliary valve in the bypass passage 4, and the throttle 17 prevents the downstream of the EGR negative pressure generation valve 7 from opening even when the auxiliary valve 18 is opened at the EGR negative pressure generation scale 7. It is carefully arranged to maintain a slight negative pressure. The diaphragm 17 may have a constant or variable hole diameter.
１５Ａは、ＥＧＲ負圧負圧発生用尺７助弁１８及び排気
ガス導入用弁１３の各アクチュエータ１１．１９．１４
に弁開閉指令信号を送る制御ユニットで、例えばマイク
ロコンピュータで構成される。制御ユニット１５Ａには
、予めエンジン運転条件に対応させてＥＧＲ負圧負圧発
生用尺７助弁１８及び排気ガス導入用弁１３の開閉の組
み合わせパターンが設定しである（この組み合わせパタ
ーンについては、後述する）。15A is each actuator 11, 19, 14 of the EGR negative pressure generation auxiliary valve 18 and the exhaust gas introduction valve 13.
A control unit that sends valve opening/closing command signals to the valve, and is composed of, for example, a microcomputer. In the control unit 15A, a combination pattern of opening and closing of the EGR negative pressure generation valve 7 auxiliary valve 18 and the exhaust gas introduction valve 13 is set in advance in accordance with the engine operating conditions (for this combination pattern, (described later).
また、制御ユニット１５Ａは、エンジン冷却水温度、エ
ンジン回転数、吸気温度等に関する信号を入力し、エン
ジンの暖機や負荷等の状態を検出する機能を有する。Further, the control unit 15A has a function of inputting signals related to engine cooling water temperature, engine speed, intake air temperature, etc., and detecting conditions such as engine warm-up and load.
本実施例では、ＥＧＲ負圧負圧発生用尺７助弁１８及び
排気ガス導入用弁１４の開閉の組み合わせパターンを第
３図のように設定しである（第３図は、バイパス通路１
６を１つとした場合を想定している）。In this embodiment, the combination pattern of opening and closing of the EGR negative pressure generation assist valve 18 and the exhaust gas introduction valve 14 is set as shown in FIG. 3 (FIG. 3 shows the bypass passage 1
(This assumes that 6 is one.)
すなわち、エンジンが暖機中で冷却水温が設定温度以下
であれば、出力の安定を優先させるために、運転の全域
にわたり排気ガス導入用弁（第３図ではこれをＥＧＲ弁
としである）１３を閉じＥＧＲは作用しない。この時、
ＥＧＲ負圧負圧発生用尺７補助弁（第３図ではこれをバ
イパス弁としである）１８は開状態にある。In other words, when the engine is warming up and the cooling water temperature is below the set temperature, the exhaust gas introduction valve (in Fig. 3, this is called the EGR valve) 13 is activated throughout the entire operation in order to prioritize output stability. Close the engine and EGR will not work. At this time,
The auxiliary valve 18 for generating EGR negative pressure (this is used as a bypass valve in FIG. 3) is in an open state.
暖機後、水温が設定温度以上の場合には、エンジンが、
■低負荷の時に、ＥＧＲ弁１４が開、ＥＧＲ負圧負圧発
生用尺７、バイパス弁１８が開、■低・中負荷の時に、
ＥＧＲ弁１４が開、ＥＧＲ負圧負圧発生用尺７、バイパ
ス弁１８が閉、■中負荷の時に、ＥＧＲ弁１４が開、Ｅ
ＧＲ負圧負圧発生用尺７、バイパス弁１８が開、■高負
荷の時には、出力本位とするためにＥＧＲ弁１３は閉で
ＥＧＲ作用はなされず、ＥＧＲ負圧負圧発生用尺７バイ
パス弁１８は開制御される。After warming up, if the water temperature is higher than the set temperature, the engine will: ■ At low load, EGR valve 14 opens, EGR negative pressure negative pressure generation scale 7 and bypass valve 18 open, ■ Low/medium load. At the time of
EGR valve 14 opens, EGR negative pressure negative pressure generation scale 7, bypass valve 18 closes, ■ At medium load, EGR valve 14 opens, E
When the load is high, the EGR valve 13 is closed and no EGR action is performed, and the bypass valve 18 for generating negative pressure is closed. Valve 18 is controlled to open.
これらの組み合わせは、制御ユニット１５Ａがエンジン
冷却氷温、回転数、吸気温度等に基づき、エンジン状態
を判断して、それに対応した信号を各アクチュエータに
送ることで実行され、そのフローチャートを第２図に示
す。第２図の８１〜Ｓ１０はステップで、このうち、Ｓ
２が暖機判断、Ｓ３が高負荷判断、Ｓ４が低負荷判断、
Ｓ５が低・中負荷判断、Ｓ６が中負荷判断のステップで
ある。These combinations are executed by the control unit 15A determining the engine condition based on the engine cooling ice temperature, rotation speed, intake air temperature, etc., and sending corresponding signals to each actuator.The flowchart is shown in FIG. Shown below. 81 to S10 in FIG. 2 are steps, of which S
2 is warm-up judgment, S3 is high load judgment, S4 is low load judgment,
S5 is a step for determining low/medium load, and S6 is a step for determining medium load.
上記制御パターンでは、上記■の低・中負荷の時に最も
ＥＧＲ負荷発生用弁下流４ａの負荷レベルが高く、排気
ガス還元量も多い。次いで、■の低・中負荷、■の中負
荷の順となる。なお、■の場合には、ＥＧＲ負荷負荷発
生用弁上４下流）大気圧のレベルにあり、エンジン気筒
の吸引力のみでＥＧＲが作用する。In the above control pattern, the load level of the EGR load generation valve downstream 4a is highest at the low/medium load of (2) above, and the amount of exhaust gas returned is also large. Next is low/medium load (■), and medium load (■). In the case of (2), the pressure is at the atmospheric pressure level (upstream and downstream of the EGR load generation valve), and EGR acts only by the suction force of the engine cylinders.
以上の制御パターンを第４図に示した従来の制御パター
ンと比較すると、従来の場合には、ＥＧＲ負圧発生用制
御弁のみの開閉だけで負圧を制御するので、本実施例の
上記■で示した低・中負荷の運転域のような負圧レベル
を設定できない。Comparing the above control pattern with the conventional control pattern shown in FIG. It is not possible to set the negative pressure level in the low/medium load operating range shown in .
これに対し、本実施例によれば、使用頻度の多いエンジ
ンの低・中負荷域で状況に適応したきめ細かなＥＧＲ制
御が可能となり、そのほか運転の広範囲にわたり、ＥＧ
Ｒ制御を行うことができる。In contrast, according to this embodiment, it is possible to perform fine-grained EGR control that adapts to the conditions in the frequently used engine's low and medium load ranges, and also to perform EGR control over a wide range of operation.
R control can be performed.
また、補助弁（バイパス弁）１８のアクチュエータ１９
は、簡易な電磁アクチュエータを使用することで、安価
にして小形のものが使用できる。In addition, the actuator 19 of the auxiliary valve (bypass valve) 18
By using a simple electromagnetic actuator, it can be made inexpensive and small.
従って、装置全体のコストをさほどかけず、しかも搭載
性に優れた装置を提供することができる。Therefore, it is possible to provide a device that does not require much cost for the entire device and has excellent mountability.
以上のように本発明におけるＥＧＲ負圧発生制御法及び
ＥＧＲ制御装置によれば、ディーゼルエンジンの吸気通
路内に多段階の負圧発生域を設定できるので、広範囲の
運転域にわたりきめ細かなＥＧＲ制御を可能とし、しか
も、構造的にも簡便で安価、小形なアクチュエータを使
用することで、コスト、搭載性に優れた装置を実現する
ことができる。As described above, according to the EGR negative pressure generation control method and EGR control device of the present invention, multi-stage negative pressure generation regions can be set in the intake passage of a diesel engine, so fine EGR control can be performed over a wide range of operating ranges. Moreover, by using a structurally simple, inexpensive, and compact actuator, it is possible to realize a device that is excellent in cost and installation.
第１図は、本発明の一実施例たるＥＧＲ制御装置の構成
図、第２図は、その動作を示すフローチャート、第３図
は上記実施例のＥＧＲ制御パターンを示す説明図、第４
図は、従来のディーゼルエンジンのＥＧＲ制御パターン
を示す説明図、第５図は、本発明の制御法を実行した時
の吸気通路の負圧発生域の状態例を示す説明図、第６図
は、ディーゼルエンジンの従来のＥＧＲ制御装置を示す
構成図である。
１・・・ディーゼルエンジン、２・・・排気管、４・・
・吸気通路、４ａ・・・ＥＧＲ負圧発生用弁の下流、５
・・・チャンバボディ、７・・・ＥＧＲ負圧発生用弁、
１１・・・アクチュエータ、１２・・・排気ガス還流通
路、１３・・・排気ガス導入用弁（ＥＧＲ弁）、１４・
・・アクチュエータ、１５Ａ・・・制御ユニット、１６
・・・バイパス通路、１７・・・絞り、１８・・・補助
弁（バイパス弁）、１９・・・アクチュエータ。
第
図
２
１・・テイーゼルエ／ジン、２・・・排気管、４・・・
吸気通路。
４ａ・・ＥＧＲ負圧発生用弁の下流、訃・・チャン・ぐ
ボアイ、７・・・ＥＧＲ負圧発生用弁、１１・・・アク
チュエータ。
１２・・・排気ガス還流通路、１３・・排気ガス導入用
弁（ＥＧＲ弁）、１４・・・アクチュエータ、１５Ａ・
・制御ユニット、１６・・バイパスＪ路、１７・・・絞
り、１８・・・補助弁（バイパス弁）、１９・・・アク
チュエータ。
第
図
第
図FIG. 1 is a configuration diagram of an EGR control device according to an embodiment of the present invention, FIG. 2 is a flowchart showing its operation, FIG. 3 is an explanatory diagram showing an EGR control pattern of the above embodiment, and FIG.
FIG. 5 is an explanatory diagram showing an EGR control pattern of a conventional diesel engine, FIG. 5 is an explanatory diagram showing an example of the state of the negative pressure generation area of the intake passage when the control method of the present invention is executed, and FIG. , is a configuration diagram showing a conventional EGR control device for a diesel engine. 1...Diesel engine, 2...Exhaust pipe, 4...
・Intake passage, 4a...Downstream of EGR negative pressure generation valve, 5
...Chamber body, 7...EGR negative pressure generation valve,
11... Actuator, 12... Exhaust gas recirculation passage, 13... Exhaust gas introduction valve (EGR valve), 14...
...Actuator, 15A...Control unit, 16
... Bypass passage, 17... Throttle, 18... Auxiliary valve (bypass valve), 19... Actuator. Fig. 2 1. Tasel engine/engine, 2. Exhaust pipe, 4.
intake passage. 4a...Downstream of the EGR negative pressure generation valve, 7...EGR negative pressure generation valve, 11...Actuator. 12... Exhaust gas recirculation passage, 13... Exhaust gas introduction valve (EGR valve), 14... Actuator, 15A...
- Control unit, 16... Bypass J path, 17... Throttle, 18... Auxiliary valve (bypass valve), 19... Actuator. Figure Figure
Claims (1)
弁を設け、該ＥＧＲ負圧発生用弁を運転条件に応じて開
閉制御することでその弁下流域に負圧を発生させ、この
負圧によりエンジンの排気ガスを排気ガス還流通路を通
して前記吸気通路に導く方式において、 前記吸気通路に前記ＥＧＲ負圧発生用弁を迂回して該Ｅ
ＧＲ負圧発生用弁の上下流を連通するバイパス通路を少
なくとも１つ設けると共に、このバイパス通路に補助弁
を設け、エンジンの運転条件に対応して前記ＥＧＲ負圧
発生用弁及び補助弁の開閉の組み合わせを変えることで
、前記吸気通路のＥＧＲ負圧発生用弁下流域に発生させ
る負圧を多段階（２段階或いはそれ以上）に制御するこ
とを特徴とするＥＧＲ負圧発生制御法。 ２、ディーゼルエンジンの吸気通路の開閉を行うＥＧＲ
負圧発生用弁と、前記ＥＧＲ負圧発生用弁を駆動するア
クチュエータと、排気通路と前記吸気通路のＥＧＲ負圧
発生用弁下流とを連通させる排気ガス還流通路と、該排
気ガス還流通路の開閉を行う排気ガス導入用弁と、該排
気ガス導入用弁を駆動するアクチュエータとを備えた装
置において、 前記吸気通路に前記ＥＧＲ負圧発生用弁を迂回して該Ｅ
ＧＲ負圧発生用弁の上下流を連通させるバイパス通路を
少なくとも１つ設け、 このバイパス通路の開閉を行う補助弁と、 該補助弁を駆動するアクチュエータと、 エンジンの運転状態を検出して、前記ＥＧＲ負圧発生用
弁、補助弁及び排気ガス導入用弁の各アクチュエータに
弁開閉指令信号を送る制御系で、予めエンジン運転条件
に対応させて前記ＥＧＲ負圧発生用弁、補助弁及び排気
ガス導入用弁の開閉の組み合わせパターンが設定してあ
る制御手段とを備えてなることを特徴とするディーゼル
エンジンのＥＧＲ制御装置。 ３、第２請求項において、前記ＥＧＲ負圧発生用弁、補
助弁及び排気ガス導入用弁を駆動するアクチュエータは
、電磁ソレノイドのオン・オフ制御により弁体を開閉駆
動するソレノイド式アクチュエータか、ダイアフラムに
印加される圧力を変化させることで弁体を開閉駆動する
ダイアフラム式アクチュエータを用いてなるディーゼル
エンジンのＥＧＲ制御装置。 ４、第２請求項又は第３請求項において、前記バイパス
通路の前記補助弁の下流に一定或いは可変の穴径の絞り
が設けてあるディーゼルエンジンのＥＧＲ制御装置。 ５、第２請求項ないし第４請求項のいずれか１項におい
て、前記バイパス通路は、前記ＥＧＲ負圧発生用弁を設
けた吸気用チャンバボディの側壁に該チャンバボディと
一体にして成形されるディーゼルエンジンのＥＧＲ制御
装置。 ６、第２請求項ないし第４請求項のいずれか１項におい
て、前記バイパス通路は、前記ＥＧＲ負圧発生用弁を設
けた吸気用チャンバボディと別体の管体で成形され、こ
の管体が前記チャンバボディ側壁に接続されるディーゼ
ルエンジンのＥＧＲ制御装置。[Claims] 1. An EGR negative pressure generation valve is provided in the intake passage of a diesel engine, and negative pressure is generated in the downstream region of the valve by controlling opening and closing of the EGR negative pressure generation valve according to operating conditions. In this method, the engine exhaust gas is guided to the intake passage through the exhaust gas recirculation passage by this negative pressure, and the EGR negative pressure generation valve is bypassed to the intake passage.
At least one bypass passage communicating upstream and downstream of the GR negative pressure generation valve is provided, and an auxiliary valve is provided in this bypass passage, and the EGR negative pressure generation valve and the auxiliary valve are opened and closed according to engine operating conditions. An EGR negative pressure generation control method, characterized in that the negative pressure generated in the intake passage downstream of the EGR negative pressure generation valve is controlled in multiple stages (two stages or more) by changing the combination of the following. 2. EGR that opens and closes the intake passage of a diesel engine
A negative pressure generation valve, an actuator that drives the EGR negative pressure generation valve, an exhaust gas recirculation passage that communicates the exhaust passage with a downstream side of the EGR negative pressure generation valve in the intake passage; In a device comprising an exhaust gas introduction valve that opens and closes, and an actuator that drives the exhaust gas introduction valve, the EGR negative pressure generation valve is bypassed in the intake passage.
At least one bypass passage is provided that communicates the upstream and downstream sides of the GR negative pressure generation valve, an auxiliary valve that opens and closes the bypass passage, an actuator that drives the auxiliary valve, and an actuator that detects the operating state of the engine and detects the operating state of the engine. A control system that sends valve opening/closing command signals to each actuator of the EGR negative pressure generation valve, auxiliary valve, and exhaust gas introduction valve. An EGR control device for a diesel engine, comprising a control means in which a combination pattern of opening and closing of an introduction valve is set. 3. In the second claim, the actuator for driving the EGR negative pressure generation valve, the auxiliary valve, and the exhaust gas introduction valve is a solenoid type actuator that opens and closes a valve body by on/off control of an electromagnetic solenoid, or a diaphragm. An EGR control device for a diesel engine that uses a diaphragm actuator that opens and closes a valve body by changing the pressure applied to the valve. 4. The EGR control device for a diesel engine according to claim 2 or 3, wherein a throttle with a constant or variable hole diameter is provided downstream of the auxiliary valve in the bypass passage. 5. In any one of claims 2 to 4, the bypass passage is formed integrally with a side wall of an intake chamber body provided with the EGR negative pressure generation valve. Diesel engine EGR control device. 6. In any one of claims 2 to 4, the bypass passage is formed of a tube separate from the intake chamber body provided with the EGR negative pressure generation valve, and is connected to the side wall of the chamber body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2043689A JPH03246362A (en) | 1990-02-23 | 1990-02-23 | Egr negative pressure generation control method and egr control device for diesel engine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2043689A JPH03246362A (en) | 1990-02-23 | 1990-02-23 | Egr negative pressure generation control method and egr control device for diesel engine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03246362A true JPH03246362A (en) | 1991-11-01 |
Family
ID=12670808
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2043689A Pending JPH03246362A (en) | 1990-02-23 | 1990-02-23 | Egr negative pressure generation control method and egr control device for diesel engine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03246362A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5507262A (en) * | 1994-06-29 | 1996-04-16 | Nippondenso Co., Ltd. | Control apparatus for internal combustion engine with exhaust gas recirculaton |
-
1990
- 1990-02-23 JP JP2043689A patent/JPH03246362A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5507262A (en) * | 1994-06-29 | 1996-04-16 | Nippondenso Co., Ltd. | Control apparatus for internal combustion engine with exhaust gas recirculaton |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2001164965A (en) | Engine control device | |
| JPH09264150A (en) | Electronic turbo charger west gate valve control device | |
| KR20030046823A (en) | Air-bypass valve system of turbo charger intercooler engine | |
| JPH1077912A (en) | Exhaust gas recirculation system | |
| JPH0243891B2 (en) | ||
| KR930702603A (en) | Air-fuel ratio control device of internal combustion engine | |
| US7980231B1 (en) | Outboard motor with an exhaust gas recirculation system and an idle exhaust relief system | |
| US4450806A (en) | Intake air throttle device of a diesel engine | |
| JPH03246362A (en) | Egr negative pressure generation control method and egr control device for diesel engine | |
| JPH04153524A (en) | Intake device of engine | |
| JP2737412B2 (en) | EGR valve rust prevention device | |
| JP2518703Y2 (en) | Auxiliary air amount control device | |
| JPS5970846A (en) | Divided-operation control type internal-combustion engine | |
| JP2008050959A (en) | Valve open close control device | |
| JP2597176Y2 (en) | Engine intake throttle device | |
| JPS59120771A (en) | Exhaust gas recirculation control method of diesel engine | |
| JPH01100317A (en) | Supercharged pressure control device for internal combustion engine | |
| JPH07233761A (en) | Exhaust reflux device for engine | |
| JP2995200B2 (en) | Engine air supply | |
| JPS6145053B2 (en) | ||
| JPS5827881A (en) | Fuel control valve | |
| JP2899596B2 (en) | Engine intake control method | |
| JPH04292534A (en) | Exhaust control device of internal combustion engine for vehicle | |
| JPS58220923A (en) | Air intake control device of internal-combustion engine | |
| JPH10318048A (en) | Exhaust gas re-circulating device for engine |