JP6701868B2 - Engine warm-up device - Google Patents

Engine warm-up device Download PDF

Info

Publication number
JP6701868B2
JP6701868B2 JP2016062394A JP2016062394A JP6701868B2 JP 6701868 B2 JP6701868 B2 JP 6701868B2 JP 2016062394 A JP2016062394 A JP 2016062394A JP 2016062394 A JP2016062394 A JP 2016062394A JP 6701868 B2 JP6701868 B2 JP 6701868B2
Authority
JP
Japan
Prior art keywords
egr
valve
exhaust
engine
intake
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.)
Active
Application number
JP2016062394A
Other languages
Japanese (ja)
Other versions
JP2017172565A (en
Inventor
和成 山本
和成 山本
慶子 柴田
慶子 柴田
宗昌 橋本
宗昌 橋本
聖 鎌倉
聖 鎌倉
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.)
Isuzu Motors Ltd
Original Assignee
Isuzu Motors 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 Isuzu Motors Ltd filed Critical Isuzu Motors Ltd
Priority to JP2016062394A priority Critical patent/JP6701868B2/en
Publication of JP2017172565A publication Critical patent/JP2017172565A/en
Application granted granted Critical
Publication of JP6701868B2 publication Critical patent/JP6701868B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

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

Description

本発明は、冷間始動されたエンジンを暖機するエンジン暖機装置に関するものである。   The present invention relates to an engine warm-up device that warms up a cold-started engine.

外部ＥＧＲ装置は、排ガスの一部を排気マニホルドから吸気マニホルドに環流させる。これにより、筒内の酸素量及び燃焼温度を低下させることができ、エンジンから排出されるＮＯｘを低減させることができる。   The external EGR device recirculates a part of the exhaust gas from the exhaust manifold to the intake manifold. As a result, the amount of oxygen in the cylinder and the combustion temperature can be reduced, and NOx emitted from the engine can be reduced.

外部ＥＧＲ装置は、ＥＧＲ通路、ＥＧＲバルブ及びＥＧＲクーラを備える。ＥＧＲクーラは、吸気マニホルドに環流する排ガスを冷却水との熱交換で冷却して排ガスのガス量を増加させ、吸気充填効率の低下を防ぐ。   The external EGR device includes an EGR passage, an EGR valve and an EGR cooler. The EGR cooler cools the exhaust gas circulating in the intake manifold by heat exchange with cooling water to increase the gas amount of the exhaust gas and prevent a decrease in intake charging efficiency.

ところで、エンジンの暖機運転時に外部ＥＧＲ装置を用いて暖機することがなされている。   By the way, during the warm-up operation of the engine, warm-up is performed using an external EGR device.

特開２０１０−０８４６４５号公報JP, 2010-084645, A 特開２００４−２４５１２０号公報JP, 2004-245120, A

しかしながら、外部ＥＧＲ装置をエンジンの冷間始動時に使用すると（１）ＥＧＲクーラでは排ガスから冷却水へ熱が奪われる。（２）また、これを防止するためにＥＧＲクーラをバイパスさせた場合でもエンジンルーム内は冷却水と同じ温度にあるため、（１）と同様に外気へと熱が奪われる。これらのために暖機に時間がかかり、燃費性能や排ガス性能が悪化するという問題があった。   However, if the external EGR device is used during cold start of the engine, (1) the EGR cooler draws heat from the exhaust gas to the cooling water. (2) Further, even when the EGR cooler is bypassed to prevent this, the temperature in the engine room is the same as the temperature of the cooling water, so heat is taken to the outside air as in (1). For these reasons, it takes a long time to warm up, and there is a problem that fuel efficiency performance and exhaust gas performance deteriorate.

また、排ガス中には水分が含まれるため、凝縮水が発生する。エンジン始動直後では、外気温度及び冷却水温度が低いこともあり、特にＥＧＲ通路の壁面付近では凝縮水が生成されやすい。このときの凝縮水の生成が繰り返されると、化学変化により凝縮水中に含まれる煤やハイドロカーボンが肥大化し、配管詰まりの原因となる可能性がある。配管詰まりは、排ガス性能や燃費に悪影響を与える可能性がある。   Further, since the exhaust gas contains water, condensed water is generated. Immediately after the engine is started, the outside air temperature and the cooling water temperature may be low, and condensed water is likely to be generated particularly near the wall surface of the EGR passage. If the generation of condensed water at this time is repeated, soot and hydrocarbon contained in the condensed water may be enlarged due to a chemical change, which may cause clogging of the pipe. Clogged pipes may adversely affect exhaust gas performance and fuel efficiency.

外部ＥＧＲ装置を使用しないと上述の問題は解決するが、それではＮＯｘの排出を抑えることができない。   If the external EGR device is not used, the above problem can be solved, but it cannot suppress NOx emission.

本発明の目的は、エンジンを冷間始動するときＮＯｘの排出を抑えつつエンジンの暖機が効率よくできるエンジン暖機装置を提供することにある。   An object of the present invention is to provide an engine warm-up device capable of efficiently warming up an engine while suppressing NOx emissions when the engine is cold started.

上述の目的を達成するため、本発明は、エンジンの冷間始動時に、エンジンを暖機するための昇温装置であって、前記エンジンの吸排気弁を開閉動するバルブ機構と、冷間始動時に前記バルブ機構での排気弁の開閉タイミングを変更して排気行程の途中で前記排気弁を強制的に閉じて排ガスを気筒内に閉じ込める内部ＥＧＲ形成装置とを備えたものである。   In order to achieve the above-mentioned object, the present invention is a temperature raising device for warming up an engine when the engine is cold started, and a valve mechanism that opens and closes an intake and exhaust valve of the engine, and a cold start. An internal EGR forming device for changing the opening/closing timing of the exhaust valve in the valve mechanism and forcibly closing the exhaust valve during the exhaust stroke to confine exhaust gas in the cylinder is provided.

本発明によれば、エンジンを冷間始動するときＮＯｘの排出を抑えつつエンジンの暖機が効率よくできる。   According to the present invention, it is possible to efficiently warm up the engine while suppressing the emission of NOx when the engine is cold-started.

本発明の一実施の形態に係るエンジンの概略説明図である。It is a schematic explanatory drawing of the engine which concerns on one embodiment of this invention. エンジン及び制御装置の概略説明図である。It is a schematic explanatory drawing of an engine and a control device. バルブタイミングを説明する線図である。It is a diagram explaining valve timing. 暖機時のエンジンの動作を説明する説明図である。It is explanatory drawing explaining operation|movement of the engine at the time of warming up.

以下、本発明の好適な実施の形態を添付図面にしたがって説明する。   Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

図１及び図２に示すように、エンジン１は、複数の気筒２を有するディーゼルエンジンからなる。エンジン１は、吸気弁３及び排気弁４を開閉動すると共に吸気弁３及び排気弁４の開閉タイミングが調節可能なバルブ機構５を有する。バルブ機構５は、後述する内部ＥＧＲ形成装置６からの制御信号で駆動されるソレノイドを有する。バルブ機構５は、吸気弁３及び排気弁４を直接的に駆動する。   As shown in FIGS. 1 and 2, the engine 1 is a diesel engine having a plurality of cylinders 2. The engine 1 has a valve mechanism 5 that can open and close the intake valve 3 and the exhaust valve 4 and can adjust the opening and closing timings of the intake valve 3 and the exhaust valve 4. The valve mechanism 5 has a solenoid driven by a control signal from an internal EGR formation device 6 described later. The valve mechanism 5 directly drives the intake valve 3 and the exhaust valve 4.

なお、バルブ機構５は、上述のものに限るものではない。例えばバルブ機構５は、内部ＥＧＲ形成装置６からの制御信号で駆動されるベーン式カム位相可変装置を備えたものであってもよく、他の形式の可変バルブタイミング機構を備えたものであってもよい。   The valve mechanism 5 is not limited to the one described above. For example, the valve mechanism 5 may include a vane type cam phase varying device driven by a control signal from the internal EGR forming device 6, or may include a variable valve timing mechanism of another type. Good.

また、エンジンの吸排気系には、過給機７が接続されると共に、外部ＥＧＲ装置８が接続されている。   A supercharger 7 and an external EGR device 8 are connected to the intake/exhaust system of the engine.

過給機７は、エンジン１の排気通路９に接続され排ガスで駆動されるタービン１０と、エンジン１の給気通路１１に接続されタービン１０からの動力で駆動されるコンプレッサ１２とを備える。また、給気通路１１には、コンプレッサ１２で圧縮された吸気を冷却するインタクーラ１３が接続されている。   The supercharger 7 includes a turbine 10 connected to the exhaust passage 9 of the engine 1 and driven by exhaust gas, and a compressor 12 connected to the supply passage 11 of the engine 1 and driven by power from the turbine 10. Further, an intercooler 13 that cools the intake air compressed by the compressor 12 is connected to the air supply passage 11.

外部ＥＧＲ装置８は、エンジン１の排気側から吸気側に排ガスを再循環させる第１ＥＧＲ通路１４と、第１ＥＧＲ通路１４に接続され第１ＥＧＲ通路１４を開閉する第１ＥＧＲバルブ１５と、第１ＥＧＲ通路１４に接続され吸気側に環流する排ガスを冷却するＥＧＲクーラ１６と、第１ＥＧＲ通路１４にＥＧＲクーラ１６をバイパスするように接続された第２ＥＧＲ通路１７と、第２ＥＧＲ通路１７に接続され第２ＥＧＲ通路１７を開閉する第２ＥＧＲバルブ１８とを備える。第１ＥＧＲ通路１４は、エンジン１のエキゾーストマニホルド１９に接続されると共にインテークマニホルド２０に接続される。ＥＧＲクーラ１６は、排ガスをエンジン冷却水との熱交換で冷却する。第１ＥＧＲバルブ１５及び第２ＥＧＲバルブ１８は、後述する昇温装置２１の内部ＥＧＲ形成装置６に接続されており、内部ＥＧＲ形成装置６からの制御信号で開度調節可能に開閉するようになっている。   The external EGR device 8 includes a first EGR passage 14 that recirculates exhaust gas from the exhaust side to the intake side of the engine 1, a first EGR valve 15 that is connected to the first EGR passage 14 to open and close the first EGR passage 14, and a first EGR passage 14 Connected to the EGR cooler 16 for cooling the exhaust gas recirculating to the intake side, a second EGR passage 17 connected to the first EGR passage 14 so as to bypass the EGR cooler 16, and a second EGR passage 17 connected to the second EGR passage 17. And a second EGR valve 18 for opening and closing. The first EGR passage 14 is connected to the exhaust manifold 19 of the engine 1 and the intake manifold 20. The EGR cooler 16 cools the exhaust gas by heat exchange with engine cooling water. The first EGR valve 15 and the second EGR valve 18 are connected to an internal EGR forming device 6 of a temperature raising device 21 described later, and are configured to open and close so that the opening can be adjusted by a control signal from the internal EGR forming device 6. There is.

昇温装置２１は、エンジン１の冷間始動時に、エンジン１を暖機するためのものである。昇温装置２１は、バルブ機構５と、冷間始動時に外部ＥＧＲを停止させると共に排気弁４のバルブタイミングで内部ＥＧＲを形成する内部ＥＧＲ形成装置６とを備える。   The temperature raising device 21 is for warming up the engine 1 when the engine 1 is cold started. The temperature raising device 21 includes a valve mechanism 5 and an internal EGR forming device 6 that forms the internal EGR at the valve timing of the exhaust valve 4 while stopping the external EGR at the cold start.

内部ＥＧＲ形成装置６は、制御装置（ＥＣＵ：エンジンコントロールユニット）からなる。内部ＥＧＲ形成装置６は、エンジン冷却水温度を検出する冷却水温度センサ２２に電気的に接続されると共に、排気通路９内の排ガス温度を測定する排ガス温度センサ２３に接続されている。   The internal EGR formation device 6 is composed of a control device (ECU: engine control unit). The internal EGR formation device 6 is electrically connected to a cooling water temperature sensor 22 that detects the engine cooling water temperature, and is also connected to an exhaust gas temperature sensor 23 that measures the exhaust gas temperature in the exhaust passage 9.

内部ＥＧＲ形成装置６は、エンジン１が冷間始動されたとき、第１ＥＧＲバルブ１５及び第２ＥＧＲバルブ１８を閉じると共に、バルブ機構５での排気弁４の開閉タイミングを通常運転時より早めるように変更する。具体的には、内部ＥＧＲ形成装置６は、冷却水温度センサ２２の検出値が、設定温度に満たないときには冷間始動されたと判断し、第１ＥＧＲバルブ１５及び第２ＥＧＲバルブ１８を全閉にすると共に、排気弁４の閉弁時期を通常運転時より早い暖機モードにするようにバルブ機構５を制御する。また、内部ＥＧＲ形成装置６は、冷却水温度センサ２２の検出値が設定温度に達したとき、排気弁４の閉弁時期を通常運転時の運転モードに戻すようにバルブ機構５を制御すると共に、第１ＥＧＲバルブ１５及び第２ＥＧＲバルブ１８を通常運転時の開度で開弁させるように制御する。設定温度は、第２ＥＧＲ通路１７が設定温度に昇温されたとき、第２ＥＧＲ通路１７内に排ガスが流れても凝縮水が生成されない温度に設定されている。   When the engine 1 is cold-started, the internal EGR formation device 6 closes the first EGR valve 15 and the second EGR valve 18, and changes the opening/closing timing of the exhaust valve 4 in the valve mechanism 5 to be earlier than during normal operation. To do. Specifically, when the detected value of the cooling water temperature sensor 22 does not reach the set temperature, the internal EGR formation device 6 determines that the engine has been cold started, and fully closes the first EGR valve 15 and the second EGR valve 18. At the same time, the valve mechanism 5 is controlled so that the closing timing of the exhaust valve 4 is set to a warm-up mode that is earlier than during normal operation. Further, the internal EGR formation device 6 controls the valve mechanism 5 so as to return the closing timing of the exhaust valve 4 to the operation mode during normal operation when the detected value of the cooling water temperature sensor 22 reaches the set temperature. , The first EGR valve 15 and the second EGR valve 18 are controlled to open at the opening during normal operation. The set temperature is set to a temperature at which condensed water is not generated even when exhaust gas flows in the second EGR passage 17 when the second EGR passage 17 is heated to the set temperature.

また、内部ＥＧＲ形成装置６は、排気弁４の開閉タイミングを制御することで内部ＥＧＲ量を調整してＮＯｘ量を少なくすべく排気弁４の開閉タイミングを制御する。この場合、内部ＥＧＲ量を多くすると、過給機のタービン１０への排気量が少なくなり、コンプレッサ１２の過給圧が低下する。このため、内部ＥＧＲ形成装置６は、吸気弁３を閉から開に動作させたとき、過給機７の過給圧が気筒内圧より高くなるように排気弁４の閉弁時期を制御して内部ＥＧＲ量を調整する。   Further, the internal EGR formation device 6 controls the opening/closing timing of the exhaust valve 4 in order to adjust the internal EGR amount by controlling the opening/closing timing of the exhaust valve 4 to reduce the NOx amount. In this case, if the amount of internal EGR is increased, the amount of exhaust gas to the turbine 10 of the supercharger decreases, and the boost pressure of the compressor 12 decreases. Therefore, the internal EGR formation device 6 controls the closing timing of the exhaust valve 4 so that the supercharging pressure of the supercharger 7 becomes higher than the cylinder internal pressure when the intake valve 3 is operated from closed to open. Adjust the internal EGR amount.

次に本実施の形態の作用を述べる。   Next, the operation of this embodiment will be described.

図１に示すように、エンジン１が始動されると、内部ＥＧＲ形成装置６は、冷却水温度センサ２２の検出値を基にエンジン１が冷間始動されたか否かを判断し、冷間始動されたとき以下の制御を行う。   As shown in FIG. 1, when the engine 1 is started, the internal EGR formation device 6 determines whether or not the engine 1 is cold started based on the detected value of the cooling water temperature sensor 22, and the cold start is performed. The following control will be performed when this is done.

エンジン１が冷間始動されたとき、内部ＥＧＲ形成装置６は、第１ＥＧＲバルブ１５及び第２ＥＧＲバルブ１８を全閉にすると共に、バルブ機構５での排気弁４の開閉タイミングを変更して排気行程の途中で排気弁４を強制的に閉じて排ガスを気筒２内に閉じ込めるように制御する。   When the engine 1 is cold started, the internal EGR formation device 6 fully closes the first EGR valve 15 and the second EGR valve 18, and changes the opening/closing timing of the exhaust valve 4 in the valve mechanism 5 to change the exhaust stroke. The exhaust valve 4 is forcibly closed in the middle of, and the exhaust gas is controlled to be confined in the cylinder 2.

これにより、排気行程中の排ガスの一部が気筒内に残って内部ＥＧＲが達成され、エンジンの暖機運転が行われる。   As a result, a part of the exhaust gas during the exhaust stroke remains in the cylinder to achieve the internal EGR, and the engine warm-up operation is performed.

図３は、吸気弁及び排気弁の開閉タイミングを、吸気弁及び排気弁の開口面積（縦軸）とクランク角（横軸）とで表したものである。横軸のＴＤＣは上死点を表し、ＢＤＣは下死点を表す。また、図中の実線は排気弁４及び吸気弁３の通常モードでの開閉弁動作を表し、破線は暖機モードでの排気弁４の開閉動作を表す。図４は、図３の膨張行程及び排気行程における吸気弁３、排気弁４及びピストン２４の動作を表すエンジンの動作説明図である。   FIG. 3 shows the opening/closing timings of the intake valve and the exhaust valve by the opening areas of the intake valve and the exhaust valve (vertical axis) and the crank angle (horizontal axis). TDC on the horizontal axis represents top dead center, and BDC represents bottom dead center. The solid line in the figure represents the opening/closing operation of the exhaust valve 4 and the intake valve 3 in the normal mode, and the broken line represents the opening/closing operation of the exhaust valve 4 in the warm-up mode. FIG. 4 is an operation explanatory diagram of the engine showing the operation of the intake valve 3, the exhaust valve 4 and the piston 24 in the expansion stroke and the exhaust stroke of FIG.

図３及び図４に示すように、エンジンが冷間始動され、内部ＥＧＲ形成装置６が排気弁４の開閉タイミングを進角させると、排気弁４は膨張行程の早いタイミングで開弁動作が開始され、排気行程の早いタイミングで閉弁動作が完了する。   As shown in FIGS. 3 and 4, when the engine is cold started and the internal EGR formation device 6 advances the opening/closing timing of the exhaust valve 4, the exhaust valve 4 starts the valve opening operation at the timing of the early expansion stroke. Then, the valve closing operation is completed at an early timing of the exhaust stroke.

例えば、図４に示すように圧縮行程から膨張行程に移る上死点にて、吸気弁３及び排気弁４は閉じられている。開閉タイミングが進角された排気弁４は、膨張行程の途中で開弁動作を開始し、膨張行程から排気行程に移る下死点近傍で略全開となる。この後、開閉タイミングが進角された排気弁４は、排気行程の早い段階で閉弁動作に移り、排気行程の途中で完全に閉弁される。これにより、気筒２中には、排ガスの一部が残留することとなる。その後、排気行程から吸気行程に移ると、吸気弁３が通常のタイミングで開閉される。インテークマニホルド２０内の圧力は気筒内圧より高いため、気筒２内に残留した排ガスが吸気側に戻ることはほとんどなく、インテークマニホルド２０からの新気が気筒２内に追加供給され、内部ＥＧＲが形成される。気筒２内に残留した排ガスは、エンジンの暖機を促進すると共に、吸気行程後の膨張行程で燃焼温度を抑制するように作用し、ＮＯｘの排出量を低減させる。   For example, as shown in FIG. 4, the intake valve 3 and the exhaust valve 4 are closed at the top dead center where the compression stroke shifts to the expansion stroke. The exhaust valve 4 whose opening/closing timing is advanced starts the valve opening operation in the middle of the expansion stroke and is substantially fully opened in the vicinity of the bottom dead center where the expansion stroke shifts to the exhaust stroke. After that, the exhaust valve 4 whose opening/closing timing is advanced moves to a valve closing operation at an early stage of the exhaust stroke, and is completely closed in the middle of the exhaust stroke. As a result, a part of the exhaust gas remains in the cylinder 2. After that, when shifting from the exhaust stroke to the intake stroke, the intake valve 3 is opened and closed at normal timing. Since the pressure in the intake manifold 20 is higher than the pressure in the cylinder, the exhaust gas remaining in the cylinder 2 hardly returns to the intake side, and fresh air from the intake manifold 20 is additionally supplied into the cylinder 2 to form an internal EGR. To be done. The exhaust gas remaining in the cylinders 2 promotes warm-up of the engine and suppresses the combustion temperature in the expansion stroke after the intake stroke, thereby reducing the NOx emission amount.

また、エンジン１の暖機中は、第１ＥＧＲバルブ１５及び第２ＥＧＲバルブ１８は全閉されており、排気弁４から排出された排ガスが第１ＥＧＲ通路１４及び第２ＥＧＲ通路１７に流れることはない。このため、第１ＥＧＲ通路１４及び第２ＥＧＲ通路１７内で凝縮水が生成されるのを防ぐことができ、煤やハイドロカーボンが肥大化して配管詰まりを引き起こすのを防ぐことができる。   Further, while the engine 1 is warming up, the first EGR valve 15 and the second EGR valve 18 are fully closed, and the exhaust gas discharged from the exhaust valve 4 does not flow into the first EGR passage 14 and the second EGR passage 17. Therefore, it is possible to prevent condensed water from being generated in the first EGR passage 14 and the second EGR passage 17, and it is possible to prevent the soot and the hydrocarbon from being enlarged and causing the pipe clogging.

この後、冷却水温度センサ２２で検出されるエンジン冷却水温度が設定温度に達すると、内部ＥＧＲ形成装置６は、排気弁４の閉弁時期を通常の運転モードに戻すと共に、第１ＥＧＲバルブ１５及び第２ＥＧＲバルブ１８を通常運転時の開度で開く。   After that, when the engine cooling water temperature detected by the cooling water temperature sensor 22 reaches the set temperature, the internal EGR formation device 6 returns the closing timing of the exhaust valve 4 to the normal operation mode and the first EGR valve 15 Also, the second EGR valve 18 is opened at the opening degree during normal operation.

このように、昇温装置２１が、エンジン１の吸排気弁３、４（吸気弁３及び排気弁４）を開閉動するバルブ機構５と、冷間始動時にバルブ機構５での排気弁４の開閉タイミングを変更して排気行程の途中で排気弁４を強制的に閉じて排ガスを気筒２内に閉じ込める内部ＥＧＲ形成装置６とを備えるものとしたため、ＮＯｘの排出を抑えつつエンジン１の暖機が効率よくできる。   As described above, the temperature raising device 21 controls the valve mechanism 5 that opens and closes the intake and exhaust valves 3 and 4 (the intake valve 3 and the exhaust valve 4) of the engine 1 and the exhaust valve 4 of the valve mechanism 5 at the time of cold start. Since the internal EGR forming device 6 that changes the opening/closing timing to forcibly close the exhaust valve 4 in the middle of the exhaust stroke to confine the exhaust gas in the cylinder 2 is used, the engine 1 is warmed up while suppressing NOx emissions. Can be done efficiently.

また、内部ＥＧＲ形成装置６は、冷間始動時に第１ＥＧＲバルブ１５及び第２ＥＧＲバルブ１８を閉じるものとしたため、排ガスがエンジン冷却水や外気に冷やされるのを防ぐことができる。このため、第１ＥＧＲ通路１４及び第２ＥＧＲ通路１７内で凝縮水の生成が繰り返されるのを防ぐことができ、第１ＥＧＲ通路１４及び第２ＥＧＲ通路１７内で凝縮水中に含まれる煤やハイドロカーボンが肥大化するのを防ぐことができる。   Further, since the internal EGR formation device 6 closes the first EGR valve 15 and the second EGR valve 18 at the time of cold start, it is possible to prevent the exhaust gas from being cooled to the engine cooling water or the outside air. For this reason, it is possible to prevent the condensed water from being repeatedly generated in the first EGR passage 14 and the second EGR passage 17, and soot and hydrocarbon contained in the condensed water in the first EGR passage 14 and the second EGR passage 17 are enlarged. Can be prevented.

内部ＥＧＲ形成装置６は、発生するＮＯｘ量が少なくなるように排気弁４の開閉タイミングを変更して内部ＥＧＲ量を調節するものとしたため、ＮＯｘ発生量を抑えつつ効率よくエンジン１を暖機できる。   Since the internal EGR formation device 6 adjusts the internal EGR amount by changing the opening/closing timing of the exhaust valve 4 so that the generated NOx amount decreases, the engine 1 can be efficiently warmed up while suppressing the NOx generation amount. ..

内部ＥＧＲ形成装置６は、排気行程でピストン２４が上死点に達する前に排気弁４を閉じるように制御すると共に、吸気弁３を閉から開に動作させたとき、過給機７の過給圧が気筒内圧より高くなるように排気弁４の閉弁時期を制御するものとしたため、吸気行程時に気筒２内に新気を安定して供給することができ、エンジン１を安定して駆動させることができる。   The internal EGR formation device 6 controls the exhaust valve 4 to be closed before the piston 24 reaches the top dead center in the exhaust stroke, and when the intake valve 3 is operated from closed to open, Since the closing timing of the exhaust valve 4 is controlled so that the supply pressure becomes higher than the cylinder pressure, fresh air can be stably supplied into the cylinder 2 during the intake stroke, and the engine 1 can be driven stably. Can be made

１ エンジン
２ 気筒
３ 吸気弁
４ 排気弁
５ バルブ機構
６ 内部ＥＧＲ形成装置 1 engine 2 cylinder 3 intake valve 4 exhaust valve 5 valve mechanism 6 internal EGR formation device

Claims (3)

エンジンの冷間始動時に、エンジンを暖機するための昇温装置であって、
前記エンジンの吸排気弁を開閉動するバルブ機構と、冷間始動時に前記バルブ機構での排気弁の開閉タイミングを変更して排気行程の途中で前記排気弁を強制的に閉じて排ガスを気筒内に閉じ込める内部ＥＧＲ形成装置とを備え、
前記エンジンの吸排気系には、外部ＥＧＲ装置が接続され、
前記外部ＥＧＲ装置は、前記エンジンの排気側から吸気側に排ガスを再循環させる第１ＥＧＲ通路と、前記第１ＥＧＲ通路に接続された第１ＥＧＲバルブと、前記第１ＥＧＲ通路に接続されたＥＧＲクーラと、前記第１ＥＧＲ通路に前記ＥＧＲクーラをバイパスするように接続された第２ＥＧＲ通路と、前記第２ＥＧＲ通路に接続された第２ＥＧＲバルブとを備え、
前記内部ＥＧＲ形成装置は、前記エンジンが冷間始動されたとき、前記第１ＥＧＲバルブ及び前記第２ＥＧＲバルブを閉じ、
前記内部ＥＧＲ形成装置は、エンジン冷却水温度が設定温度に達したとき、前記排気弁の閉弁時期を通常の運転モードに戻すように前記バルブ機構を制御すると共に、前記第１ＥＧＲバルブ及び前記第２ＥＧＲバルブを通常運転時の開度にするように制御し、
前記設定温度は、前記第２ＥＧＲ通路が設定温度に昇温されたとき、前記第２ＥＧＲ通路内に排ガスが流れても凝縮水が生成されない温度に設定された
ことを特徴とする昇温装置。 A temperature raising device for warming up the engine when the engine is cold started,
A valve mechanism that opens and closes the intake and exhaust valves of the engine and the opening and closing timing of the exhaust valve in the valve mechanism during cold start to forcefully close the exhaust valve in the middle of the exhaust stroke to exhaust the exhaust gas into the cylinder. And an internal EGR forming device that is confined in
An external EGR device is connected to the intake/exhaust system of the engine,
The external EGR device includes a first EGR passage that recirculates exhaust gas from an exhaust side to an intake side of the engine, a first EGR valve connected to the first EGR passage, and an EGR cooler connected to the first EGR passage, A second EGR passage connected to the first EGR passage so as to bypass the EGR cooler; and a second EGR valve connected to the second EGR passage,
The internal EGR formation device closes the first EGR valve and the second EGR valve when the engine is cold started,
The internal EGR formation device controls the valve mechanism to return the closing timing of the exhaust valve to a normal operation mode when the engine cooling water temperature reaches a set temperature, and the first EGR valve and the first EGR valve 2 Control the EGR valve so that it has the opening for normal operation,
The set temperature is set to a temperature at which condensed water is not generated even when exhaust gas flows in the second EGR passage when the second EGR passage is heated to the set temperature . 内部ＥＧＲ形成装置は、発生するＮＯｘ量が少なくなるように前記排気弁の開閉タイミングを変更して内部ＥＧＲ量を調節する請求項１に記載の昇温装置。 Internal EGR forming apparatus, heating apparatus according to claim 1 for adjusting the internal EGR amount by changing the opening and closing timing of the exhaust valve as the amount of NOx generated is reduced. エンジンの吸排気系に過給機が接続され、前記内部ＥＧＲ形成装置は、排気行程でピストンが上死点に達する前に排気弁を閉じるように制御すると共に、吸気弁を閉から開に動作させたとき、前記過給機の過給圧が気筒内圧より高くなるように前記排気弁の閉弁時期を制御する請求項１又は２に記載の昇温装置。 A supercharger is connected to the intake/exhaust system of the engine, and the internal EGR formation device controls the exhaust valve to close before the piston reaches the top dead center in the exhaust stroke, and operates the intake valve from close to open. The temperature raising device according to claim 1 or 2 , wherein when the control is performed, the closing timing of the exhaust valve is controlled so that the supercharging pressure of the supercharger becomes higher than the cylinder internal pressure.
JP2016062394A 2016-03-25 2016-03-25 Engine warm-up device Active JP6701868B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2016062394A JP6701868B2 (en) 2016-03-25 2016-03-25 Engine warm-up device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2016062394A JP6701868B2 (en) 2016-03-25 2016-03-25 Engine warm-up device

Publications (2)

Publication Number Publication Date
JP2017172565A JP2017172565A (en) 2017-09-28
JP6701868B2 true JP6701868B2 (en) 2020-05-27

Family

ID=59973784

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2016062394A Active JP6701868B2 (en) 2016-03-25 2016-03-25 Engine warm-up device

Country Status (1)

Country Link
JP (1) JP6701868B2 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7276589B2 (en) * 2020-02-20 2023-05-18 日産自動車株式会社 CONTROL METHOD AND CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINE
JP7405038B2 (en) 2020-08-07 2023-12-26 いすゞ自動車株式会社 Control device

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1130135A (en) * 1997-07-11 1999-02-02 Nippon Soken Inc Controller of diesel engine
JP4075638B2 (en) * 2003-02-18 2008-04-16 三菱自動車エンジニアリング株式会社 Engine valve timing control device
JP2009008023A (en) * 2007-06-28 2009-01-15 Toyota Motor Corp Exhaust control device for internal combustion engine
JP2009085053A (en) * 2007-09-28 2009-04-23 Toyota Motor Corp Control device for compression ignition internal combustion engine
JP2010121574A (en) * 2008-11-21 2010-06-03 Toyota Motor Corp Control device for internal combustion engine
JP5262788B2 (en) * 2009-02-12 2013-08-14 トヨタ自動車株式会社 Control device for an internal combustion engine with a supercharger
KR101518883B1 (en) * 2009-12-03 2015-05-12 현대자동차 주식회사 Apparatus and method for controlling a continuous variable valve lift actuator of diesel engine
JP2013167218A (en) * 2012-02-16 2013-08-29 Toyota Motor Corp Recirculating device of internal combustion engine
US9790852B2 (en) * 2013-06-12 2017-10-17 Toyota Jidosha Kabushiki Kaisha Condensed water treatment device for internal combustion engine

Also Published As

Publication number Publication date
JP2017172565A (en) 2017-09-28

Similar Documents

Publication Publication Date Title
RU112869U1 (en) EXHAUST GAS HEATING SYSTEM AND EXHAUST GAS COOLING
EP2181260B1 (en) Control apparatus and control method for internal combustion engine
US7066158B2 (en) Homogeneous charge compression ignition internal combustion engine that performs EGR, and ignition timing control method for the engine
US6807956B2 (en) Method for a cylinder-charge control in the case of an internal combustion engine
US20160195031A1 (en) Partial deactivation of an internal combustion engine
JP5348338B2 (en) Engine control device
JP2007315230A (en) Apparatus for recirculating exhaust gas of internal combustion engine
US9879617B2 (en) Control apparatus of engine
US20170030279A1 (en) Exhaust-gas-turbocharged internal combustion engine with partial deactivation and method for operating an internal combustion engine of said type
JP4442643B2 (en) Exhaust gas purification control device for internal combustion engine
US20180266365A1 (en) Exhaust gas control apparatus of internal combustion engine
JP3992016B2 (en) Control device for premixed compression self-ignition internal combustion engine
JP6520982B2 (en) Control device for internal combustion engine
JP6701868B2 (en) Engine warm-up device
JP2009264335A (en) Multistage supercharging system for internal combustion engine
JP2009085053A (en) Control device for compression ignition internal combustion engine
JP5381867B2 (en) Automatic stop device for diesel engine
JP4719142B2 (en) Multi-cylinder 4-cycle engine with internal EGR system
JP2012246797A (en) Internal combustion engine control apparatus
US11230981B2 (en) Supercharger-equipped engine
JP2015121156A (en) Control device of internal combustion engine
JP6399198B1 (en) Turbocharged engine
JP2004100521A (en) Combustion control apparatus for internal combustion engine
JP6962241B2 (en) Supercharged engine
JP2006112272A (en) Intake air temperature control system for internal combustion engine

Legal Events

Date Code Title Description
A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A821

Effective date: 20160325

A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20190228

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20191024

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20191112

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20200108

Free format text: JAPANESE INTERMEDIATE CODE: A821

Effective date: 20200108

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: 20200407

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20200420

R150 Certificate of patent or registration of utility model

Ref document number: 6701868

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150