JPS5910723A - Secondary air control device for internal-combustion engine - Google Patents
Secondary air control device for internal-combustion engineInfo
- Publication number
- JPS5910723A JPS5910723A JP3152982A JP3152982A JPS5910723A JP S5910723 A JPS5910723 A JP S5910723A JP 3152982 A JP3152982 A JP 3152982A JP 3152982 A JP3152982 A JP 3152982A JP S5910723 A JPS5910723 A JP S5910723A
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- secondary air
- air
- chamber
- pressure chamber
- 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
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
- F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
- F01N3/22—Control of additional air supply only, e.g. using by-passes or variable air pump drives
- F01N3/227—Control of additional air supply only, e.g. using by-passes or variable air pump drives using pneumatically operated valves, e.g. membrane valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
- F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
- F01N3/22—Control of additional air supply only, e.g. using by-passes or variable air pump drives
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Toxicology (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Exhaust Gas After Treatment (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の技術分野〕
本発明は内燃機関の２次空気制御装置に係り、特に高負
荷・高速時にのみ排気系への２次空気の供給を確実に断
ち、排気ガスの悪化をきだすことなく排気系の排気温度
や触媒温度の上昇による熱害等を防止し得る内燃機関の
２次空気制御装置に関する。Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a secondary air control device for an internal combustion engine, and in particular, it reliably cuts off the supply of secondary air to the exhaust system only at high loads and high speeds, thereby reducing exhaust gas. The present invention relates to a secondary air control device for an internal combustion engine that can prevent heat damage caused by a rise in exhaust gas temperature or catalyst temperature in an exhaust system without causing deterioration of the temperature.
自動車等のエンジンには、燃焼室から排出される排気ガ
スに含まれるＨＣやＣＯを再燃焼させて浄化処理するた
めに、排気系に２次空気を供給する２次空気供給装置が
設けられている。２次空気供給装置はエアポンプから２
次空気供給通路を介して排気系に２次空気を送供するが
、高負荷・高速運転時においても２次空気を供給するど
排気系が過熱され、触媒コノバータやサーマルリアクタ
が熱損傷されるなどの問題がある。このだめ、２次空気
供給通路には、負荷変動等に応じて排気系への２次空気
喰を制御する２次空気制御装置が採用されている。Engines such as automobiles are equipped with a secondary air supply device that supplies secondary air to the exhaust system in order to reburn and purify HC and CO contained in exhaust gas discharged from the combustion chamber. There is. The secondary air supply device is from the air pump 2
Secondary air is supplied to the exhaust system through the secondary air supply passage, but even during high-load and high-speed operation, the exhaust system is overheated and the catalytic converter and thermal reactor may be damaged by heat. There is a problem. However, the secondary air supply passage is equipped with a secondary air control device that controls the intake of secondary air to the exhaust system in accordance with load fluctuations and the like.
以下に従来のこの種制御装置について説明する。A conventional control device of this type will be explained below.
従来の２次空気量制御は、主に吸気管負圧を利用するも
のであり、第１図のように構成されている。Conventional secondary air amount control mainly utilizes intake pipe negative pressure, and is configured as shown in FIG.
図において、ａはエアポンプからの２次空気を排気マニ
ホルドに送供するだめの２次空気供給通路であり、２次
空気供給通路ａには、２次空気制御バルブｂが設けられ
ている。２次空気制御バルブｌ）は、供給通路ａから２
次空気が流入する流入室Ｃと、流入室Ｃの空気を大気解
放等ダイバートさせるダイバート室ｄと、吸気管負圧信
号チューブＣを介して吸気マニホルドと連通しダイヤフ
ラムｆにより密閉状に区画されたダイヤフラム室ｇとを
有している。吸気管負圧は、エンジン負荷に比例し、低
負荷のときには吸気管負圧は大きく（低圧）、ダイヤフ
ラム室ｇ内負圧によりダイヤフラ１、 （はスプリング
１．をＦＦ、縮しつつ図中７Ｆ方へと引っ張られ、ダイ
ヤフラノ・「に井棒電で連結された弁体Ｊは流入室Ｃと
ダイバート室（１とを連通ずる連通口１（を寒ぐことと
なり、流入室Ｃの空気は流出０看より排気マニホルド側
の２次空気供給通路ａを経て排気マニホルドに供給され
る（第１図実線矢印）。In the figure, a is a secondary air supply passage for supplying secondary air from the air pump to the exhaust manifold, and the secondary air supply passage a is provided with a secondary air control valve b. The secondary air control valve l) is connected to the supply passage a to 2
An inlet chamber C into which the next air flows, a divert chamber d which diverts the air in the inlet chamber C to release to the atmosphere, etc., communicates with the intake manifold via an intake pipe negative pressure signal tube C, and is hermetically divided by a diaphragm f. It has a diaphragm chamber g. The negative pressure in the intake pipe is proportional to the engine load, and when the load is low, the negative pressure in the intake pipe is large (low pressure). The valve body J connected to the diaphragm and the diversion chamber cools the communication port 1 (which connects the inflow chamber C and the divert chamber 1), and the air in the inflow chamber C cools down. Outflow 0 is supplied to the exhaust manifold through the secondary air supply passage a on the exhaust manifold side (solid line arrow in Figure 1).
一方、エンジン高負荷のときには、吸気管負圧は小さく
大気圧に近づくだめ、ダイヤフラム「はスプリング１１
の復元力により右方へと戻され、弁体Ｊも右方へと移動
し弁体Ｊにより流出０看は覆われ２次空気供給通路ａは
遮断され、流入室Ｃに供給された空気は連通口によりダ
イバート室ｄに流入し排出口ｍより排出され（第１図破
線矢印）、排気マニホルドへの２次空気の供給は断たれ
る。On the other hand, when the engine is under high load, the intake pipe negative pressure is small and cannot approach atmospheric pressure, so the diaphragm ``spring 11''
is returned to the right by the restoring force, and the valve body J also moves to the right, the outflow area is covered by the valve body J, the secondary air supply passage a is blocked, and the air supplied to the inflow chamber C is The air flows into the divert chamber d through the communication port and is discharged through the exhaust port m (dashed arrow in FIG. 1), and the supply of secondary air to the exhaust manifold is cut off.
と、ころが、このような吸気管負圧変動すなわち負荷変
動による２次空気制御では、所定以上の高負荷のときに
は、エンジン回転数に関係なく２次空気をダイバートさ
せることとなり、第２図中、斜線で示すように２次空気
ダイバート域がエンジン低回転域にも存在する。しかし
ながら、排気系が過熱され触媒コンバータの熱害などが
問題となるのは、高負荷・高速回転域だけであり、上記
のように高負荷・低速域においても２次空気をダイバー
トさせて排気系への２次空気の供給を止めてしまうと排
気ガスの悪化を招いてし壕う。このことは、殊に高負荷
走行時間が長い高地走行において問題となる。However, in secondary air control based on intake pipe negative pressure fluctuations, that is, load fluctuations, when the load is higher than a predetermined level, the secondary air is diverted regardless of the engine speed, as shown in Figure 2. , as shown by diagonal lines, a secondary air divert region also exists in the low engine speed region. However, problems such as overheating of the exhaust system and heat damage to the catalytic converter only occur in the high load/high speed range, and as mentioned above, even in the high load/low speed range, secondary air is diverted to the exhaust system. If the supply of secondary air to the engine is stopped, the exhaust gas will worsen. This becomes a problem especially when driving at high altitudes for a long time under high load.
このだめ、吸気管負圧のみならず、これにエンジンスピ
ードセンサにより検出されたエンジン回転速度をも加味
して高負荷・高速域のみ排気系への２次空気を遮断制御
する方法も提案されている。To solve this problem, a method has been proposed in which not only the intake pipe negative pressure but also the engine speed detected by the engine speed sensor is taken into account to control the secondary air to the exhaust system only in high load and high speed ranges. There is.
しかしながら、この方法では、エンジンスピードセンサ
などが追加されるため、配管・配線が複雑化すると共に
、コストアップを余儀なくされるという問題がある。However, in this method, since an engine speed sensor and the like are added, piping and wiring become complicated, and costs are inevitably increased.
本発明は以上の従来の問題点全治効に解決すべく創案さ
れたものであり、本発明の目的は、高負荷・高速時にの
み排気系への２次空気供給を確実に遮断でき、排気ガス
の悪化をきたすことなく、排気系の過熱による熱害等を
防止し得、しかも構造簡単な２次空気制御装置を提供す
ることにある。The present invention has been devised to completely solve the above-mentioned conventional problems, and an object of the present invention is to reliably cut off the secondary air supply to the exhaust system only at high load and high speed, and to reduce exhaust gas. To provide a secondary air control device which can prevent heat damage caused by overheating of an exhaust system without causing deterioration of air flow, and which has a simple structure.
以下に本発明の好適一実施例を添付図面に従って詳述す
る。A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.
第３図において、１はエンジン本体でアリ、エンジン本
体１には、その各燃焼室に気化器２からの混合気を供給
する吸気マニホルド３が接続されると共に、燃焼室から
の燃焼排ガスを排気すべく排気マニホルド４が連設され
ている。まだ、５はエンジンのクランク軸にベルト等を
介して連結されエンジン回転により駆動され２次空気を
排気系に供給するエアポンプである。エアポンプ５はエ
アクリ−す７、吸気管６を介して吸気した空気を２次空
気として、２次空気供給通路８を通って排気マニホルド
４に設けられた２次空気噴射スハージャ９から排気−マ
ニホルド４内に噴射するようになっている。なお、１０
は２次空気供給通路８への排気ガスの流入を阻止する逆
止弁である。まだ、１１け排気管であり、排気管１１に
は触媒コ／ノ＜−夕１２が設けられている。In Fig. 3, reference numeral 1 denotes the engine body. The engine body 1 is connected to an intake manifold 3 that supplies the air-fuel mixture from the carburetor 2 to each combustion chamber, and also exhausts combustion exhaust gas from the combustion chambers. An exhaust manifold 4 is provided in series. Reference numeral 5 designates an air pump that is connected to the engine crankshaft via a belt or the like and is driven by engine rotation to supply secondary air to the exhaust system. The air pump 5 uses the air taken in through the air cleaner 7 and the intake pipe 6 as secondary air, and supplies the air through the secondary air supply passage 8 to the exhaust manifold 4 from the secondary air injection shajar 9 provided in the exhaust manifold 4. It is designed to be sprayed inside. In addition, 10
is a check valve that prevents exhaust gas from flowing into the secondary air supply passage 8. There are still 11 exhaust pipes, and the exhaust pipe 11 is provided with a catalytic converter 12.
２次空気供給通路８には、エアポンプ５から送られる２
次空気の空気量を制御する２次空気制御装置１３の中空
筒体状のバルブケーシング１４がＮＱ ケラれている。The secondary air supply passage 8 has 2 air supplied from the air pump 5.
The hollow cylindrical valve casing 14 of the secondary air control device 13 that controls the amount of secondary air is NQ vignetted.
バルブケーンフグ１４内には、隔壁１５により隔だれて
第１圧力室１６と第２圧力室１７とが区画されると共に
、ダイヤフラム１８によりダイヤフラム室１９とスプリ
ング室３７とが１メ画形成されている。第１圧力室１６
には、エアポツプ５からの２次空気が流入する空気流入
口２０と、第１圧力室１６に流入した空気を排気マニホ
ルド４側の２次空気供給通路８に送る空気流出口２１と
が形成されている。まだ第１圧力室１６と第２圧力室１
７とは隔壁１５に形成された連通口２２を介して連通さ
れている。Inside the valve cane puffer 14, a first pressure chamber 16 and a second pressure chamber 17 are separated by a partition wall 15, and a diaphragm chamber 19 and a spring chamber 37 are formed in one square by a diaphragm 18. There is. First pressure chamber 16
An air inlet 20 through which the secondary air from the air pop 5 flows in, and an air outlet 21 through which the air flowing into the first pressure chamber 16 flows into the secondary air supply passage 8 on the exhaust manifold 4 side are formed. ing. Still the first pressure chamber 16 and the second pressure chamber 1
7 through a communication port 22 formed in the partition wall 15.
更に、第１圧力室１６には、連通口２２と空気流出口２
１とを開閉するだめの弁ｔ＊２３が設けられており、弁
体２３とダイヤフラノ、１８との間は、連通口２２を挿
通させて設けられだ弁棒２４により連結されている。ま
た、第１圧力室１６とタ゛イヤフラム室１９とは信号取
出チューブ２５により連通接続されており、第１圧力室
１６の）「力変動がダイヤフラム室１９に伝達され、こ
れに応じてダイヤフラム１８が偏位することにより弁体
２３が移動シフ、連通口２２捷たけ空気流出口２１が閉
塞されるように構成されている。大気解放されたスプリ
ング室３７には、ダイヤフラノ、室１９内の圧力が設定
圧具」二にならないと、ダイヤフラム１８が右方へと移
動して弁体２３が連通口２２から離間しないように圧力
調整するスプリング２６が設けられている。スプリング
２６はスプリング受け２７とダイヤフラム１８との間に
介設され、また、スプリング受け２７は、弁棒２４のガ
イドとしての機能も有している。Furthermore, the first pressure chamber 16 has a communication port 22 and an air outlet 2.
A valve t*23 is provided to open and close the valve body 23 and the diaphragm 18, and the valve body 23 and the diaphragm 18 are connected by a valve rod 24 which is inserted through the communication port 22. Further, the first pressure chamber 16 and the diaphragm chamber 19 are connected to each other by a signal extraction tube 25, and force fluctuations in the first pressure chamber 16 are transmitted to the diaphragm chamber 19, and the diaphragm 18 is biased accordingly. When the valve body 23 is positioned, the valve body 23 is moved, the communication port 22 is closed, and the air outlet 21 is closed. A spring 26 is provided to adjust the pressure so that the diaphragm 18 moves to the right and the valve body 23 does not separate from the communication port 22 unless the set pressure is reached. The spring 26 is interposed between the spring receiver 27 and the diaphragm 18, and the spring receiver 27 also functions as a guide for the valve rod 24.
信号取出チューブ２５には、圧力調整オリフィス２８が
設けられると共に、信号取出チコーーブ２５内の空気を
第２圧力室１７にリークさせるだめのリーク通路２９が
第２圧力室１７と信号取出デユープ２５との間に介設さ
れている。リーク通路２９には、信号取出チューブ２５
から第２圧力室１７へのリーク量を調整するリーク調整
オリフィス３０が設けられている。第２圧力室１７には
、リーク通路２９から第２圧力室１７にリークされた空
気、あるいは第１圧力室１６から連通口２２を介して第
２圧力室１１に流入してきた空気を大気開放するだめの
開口３１が設けられている。The signal extraction tube 25 is provided with a pressure adjustment orifice 28 , and a leak passage 29 for leaking the air in the signal extraction tube 25 to the second pressure chamber 17 is provided between the second pressure chamber 17 and the signal extraction duplex 25 . is interposed in between. A signal extraction tube 25 is installed in the leak passage 29.
A leak adjustment orifice 30 is provided to adjust the amount of leak from the pressure chamber 17 to the second pressure chamber 17. The second pressure chamber 17 is vented to the atmosphere from air leaked from the leak passage 29 to the second pressure chamber 17 or from air flowing into the second pressure chamber 11 from the first pressure chamber 16 through the communication port 22. A reservoir opening 31 is provided.
次に、本実施例の作用について述べる。Next, the operation of this embodiment will be described.
排気系の排気圧力は、エンジン回転数及び負荷に比例し
て大きくなるが、エアポンプ５の吐出圧も排気圧力に打
ち勝つように排気圧力に比例して増大する。そこで、本
発明では、エアポンプ５の吐出圧力を利用して排気系へ
の２次空気の供給を制御している。The exhaust pressure of the exhaust system increases in proportion to the engine speed and load, and the discharge pressure of the air pump 5 also increases in proportion to the exhaust pressure so as to overcome the exhaust pressure. Therefore, in the present invention, the discharge pressure of the air pump 5 is used to control the supply of secondary air to the exhaust system.
エアポツプ５から吐出された空気は、２次空気供給通路
８を通って空気流入口２０より第１圧力室１６内に流入
するが、エンジンの低中速、低中負荷運転時においては
、第１圧力室１６の圧力（エアポツプの吐出圧）ｐ＋は
低い。従って、信号取出チュー７２５を介して連通され
たダイヤフラム室１９の圧力も低く、ダイヤフラム１８
はスプリング２６により図中左方へと押され、弁体２３
は隔壁１５に押し付けられ弁体２３により連通口２２は
閉成される。このため、第１圧力室１６に流入した空気
は、空気流出口２１より２次空気供給通路８を通って２
次空気噴射スパージャ９から排気マニホルド４内に噴射
される（２次空気インジェクション）。このときの第１
圧力室１６の圧力ｐ、は、第４図中実線で示すように、
エンジン回転数及び負荷とともに増大している。（図中
、−２００ｍｍＨｇ 、−１００ｍｍＨｇは負荷に比例
する吸気管負圧で、ＷＯＴは絞り弁全開時のときのもの
であるっ）また、第１圧力室１６から圧力調整オリフィ
ス２８を介して供給される信号取出チューブ２５内空気
の圧力Ｐ３は、第５図中、実線で示すようになる。信号
取出チューブ２５の空気はＩＪ、−り通路２９から第２
圧力室１７にリークされるが、このＩＪ−り量は少ない
ので、開口３１により大気開放される第２圧力室１７内
の圧力Ｐ２は、はぼ大気圧である（高速回転のときでも
２〜３１Ｍ Ｉｇ程度である。）。Air discharged from the air pop 5 passes through the secondary air supply passage 8 and flows into the first pressure chamber 16 from the air inlet 20. The pressure in the pressure chamber 16 (air pop discharge pressure) p+ is low. Therefore, the pressure in the diaphragm chamber 19 communicated via the signal extraction tube 725 is also low, and the diaphragm 18
is pushed to the left in the figure by the spring 26, and the valve body 23
is pressed against the partition wall 15, and the communication port 22 is closed by the valve body 23. Therefore, the air flowing into the first pressure chamber 16 passes through the secondary air supply passage 8 from the air outlet 21 and into the second pressure chamber 16.
Secondary air is injected into the exhaust manifold 4 from the sparger 9 (secondary air injection). At this time, the first
The pressure p in the pressure chamber 16 is as shown by the solid line in FIG.
It increases with engine speed and load. (In the figure, -200mmHg and -100mmHg are intake pipe negative pressures proportional to the load, and WOT is when the throttle valve is fully open.) Also, the pressure is supplied from the first pressure chamber 16 through the pressure adjustment orifice 28. The pressure P3 of the air inside the signal extraction tube 25 is as shown by the solid line in FIG. The air in the signal extraction tube 25 is supplied to the IJ from the second passage 29.
However, since the amount of IJ leaked to the pressure chamber 17 is small, the pressure P2 in the second pressure chamber 17, which is opened to the atmosphere through the opening 31, is approximately atmospheric pressure (even at high speed rotation, 31M Ig).
エンジンの回転数まだは負荷が上昇すると、第１圧力室
１６の圧力Ｐ、が上昇し、これに伴って信号取出チュー
ブ２５の圧力Ｐ３も上昇する。そして、ダイヤフラム室
１９圧がスプリング２６の設定圧以上になると、ダイヤ
フラム１８は右方へ、と偏位し、これに従って弁体２３
は隔壁１５より離れ、第３図中、鎖線で示すように、空
気流出口２１は塞がれ、連通口２２が開成される。こう
して、第１圧力室１６に流入した２次空気は、連通口２
２から第２圧力室１７に流入し開口３１より大気解放さ
れる（２次空気ダイバート）。第１圧力室１６の空気が
第２圧力室１７にダイバートされると、圧力Ｐ、は第４
図中、破線で示すように急激に低下するが、第２圧力室
１７の圧力Ｐ２は、第２圧力室１７にダイバートされる
２次空気量が多く、また開口３１が絞りとして機能する
ため、第４図中一点鎖線で示すように大幅に増大する。When the engine speed and load increase, the pressure P in the first pressure chamber 16 increases, and the pressure P3 in the signal extraction tube 25 increases accordingly. When the pressure in the diaphragm chamber 19 becomes equal to or higher than the set pressure of the spring 26, the diaphragm 18 is deflected to the right, and accordingly the valve body 23
is separated from the partition wall 15, and as shown by the chain line in FIG. 3, the air outlet 21 is closed and the communication port 22 is opened. In this way, the secondary air that has flowed into the first pressure chamber 16 is transferred to the communication port 2.
2 into the second pressure chamber 17 and released to the atmosphere through the opening 31 (secondary air divert). When the air in the first pressure chamber 16 is diverted to the second pressure chamber 17, the pressure P,
Although the pressure P2 in the second pressure chamber 17 decreases rapidly as shown by the broken line in the figure, the amount of secondary air diverted to the second pressure chamber 17 is large, and the opening 31 functions as a restrictor. As shown by the dashed line in FIG. 4, it increases significantly.
このため信号取出チューブ２５かもリーク通路２９を介
してリークされる空気量は」二記インジェクション時よ
り少なくなり、圧力Ｐ３は、第５図中、破線で示すよう
に、インジェクション時よりやや」二昇する。それ故、
弁体２３は第１ ＩＥ力室１６の圧力Ｐ＋の低下にかか
わらず、２次空気供給通路８の空気流入口２１に密着し
た！、ま保持され、弁体２３がばたつくチャタリングの
発生を防止できる。本発明の特長とするところは、この
ように第１圧力室１６の圧力Ｐ１が、ダイバート時には
急激に落ちてしまうため、圧力Ｐ＋ だけでは弁体２３
の開閉制御はできないが、ダイバート時に上昇する第２
圧力室１７の圧力Ｐ２を利用し、圧力調整オリフィス２
８、リーク調整オリフィス３０を上述した条件を満足す
るように選定し、信号取出チューブ２５内の圧力Ｐ３が
イ／ジエクション時、ダイバート時ともに、はぼ同一と
なるようにしたことにある。Therefore, the amount of air leaked through the signal extraction tube 25 and the leak passage 29 is smaller than during the second injection, and the pressure P3 is slightly higher than during the second injection, as shown by the broken line in Fig. 5. do. Therefore,
The valve body 23 was in close contact with the air inlet 21 of the secondary air supply passage 8 regardless of the decrease in the pressure P+ in the first IE force chamber 16! , it is possible to prevent the occurrence of chattering caused by flapping of the valve body 23. The feature of the present invention is that the pressure P1 in the first pressure chamber 16 drops rapidly during the diversion, so if only the pressure P+
Although it is not possible to control the opening and closing of the
Using the pressure P2 of the pressure chamber 17, the pressure adjustment orifice 2
8. The leak adjustment orifice 30 is selected to satisfy the above-mentioned conditions so that the pressure P3 inside the signal extraction tube 25 is almost the same during both ejection and diversion.
エンジンが高速、高負荷域から低中速、低中負荷域に戻
ると、圧力ＰＩ、Ｐ２の低下とともに圧力Ｐ３も低下し
、ダイヤフラム１８は左方へと偏位し、弁体２３は空気
流出口２１から離れ隔壁１５に密着し連通口２２は遮断
され、２次空気は２次空気噴射スパージャ９から噴射さ
れ、再びインジエク／ヨン状態となる。第５図でＰ４を
設定圧とすると、ＷＯＴ 、 −＋ ００關Ｈｇ、−２
００陥Ｈｇ、の負荷では回転数Ｎ、、Ｎ、、Ｎ３以上で
２次空気はダイバートされるどととなる。When the engine returns from the high-speed, high-load range to the low-medium speed and low-medium load range, the pressure P3 decreases as well as the pressures PI and P2, the diaphragm 18 deviates to the left, and the valve body 23 It separates from the outlet 21 and comes into close contact with the partition wall 15, and the communication port 22 is blocked, and the secondary air is injected from the secondary air injection sparger 9, returning to the injected/yon state. In Figure 5, if P4 is the set pressure, WOT, -+ 00Hg, -2
At a load of 0.00 Hg, the secondary air is diverted at rotation speeds N, , N, , N3 or higher.
以上のようにして、本実施例の２次空気制御装置１３に
より、第６図に斜線で示すように、排気系への２次空気
の供給を断ちダイバートさせる２次空気ダイバート域が
高速・高負荷域に限定されるだめ、排気ガス中のＣＯや
ＨＣの増大を招くことなく、触媒コンバータ１２等の過
熱を防止することができる。As described above, the secondary air control device 13 of this embodiment allows the secondary air divert area to cut off and divert the supply of secondary air to the exhaust system at high speed and high speed, as shown by diagonal lines in FIG. Since it is limited to the load range, overheating of the catalytic converter 12 and the like can be prevented without causing an increase in CO and HC in the exhaust gas.
なお、上記実施例において、圧力Ｐ、、Ｐ、の変化によ
って変動する信号取出チューブ２５の圧力Ｐ３の急激な
変化を抑止し、弁体２３のチャタリング発生を更に防止
すべく、第３図中、破線で示すように、信号取出チュー
ブ２５にオリフィス３２を設けてもよい。本実施例にお
いては、ダイヤフラム１８、ダイヤフラム室１９、弁体
２３、弁棒２４、スプリング２６等が開閉作動手段であ
る。In the above embodiment, in order to suppress sudden changes in the pressure P3 of the signal extraction tube 25, which fluctuates due to changes in the pressures P, P, and to further prevent chattering of the valve body 23, the following steps are shown in FIG. An orifice 32 may be provided in the signal extraction tube 25 as shown by the broken line. In this embodiment, the diaphragm 18, the diaphragm chamber 19, the valve body 23, the valve rod 24, the spring 26, etc. are the opening/closing operating means.
上記実施例における２次空気制御は、エアボ／プ５から
吐出され第１圧力室１６に流入する２次空気自身の圧力
によって弁体２３を作動するものであるが、第７図、第
８図に示すように、これとは別系統の吸気マニホルド負
圧を作動源として弁体２３を作動するようにしてもよい
。The secondary air control in the above embodiment operates the valve body 23 by the pressure of the secondary air itself discharged from the air pump 5 and flowing into the first pressure chamber 16. As shown in FIG. 2, the valve body 23 may be operated using the intake manifold negative pressure in a separate system as the operating source.
第７図においては、信号取出チューブ２５に吸気管負圧
制御弁３３が設けられている。低中速、低中負荷域では
、第１圧力室１６の圧力Ｐ＋は低く、未だ制御弁３３の
ダイヤフラノ、３４を作動し得す、バルブ３５は吸気管
からの負圧通路３６を閉じ、大気がスプリング室３７に
導かれており、ダイヤフラム１８は左方に押され弁体２
３は連通口２２を遮断し、２次空気は排気系へと送られ
インジェクション状態にある。負荷又は工／ジン回転が
−にかり高負荷・高速域になると、圧力Ｐ３が上昇し、
’＋ｌ１ｌｌ ｉ＋＋弁３３のダイヤフラム室３８の圧
力も上昇し、ダイヤフラム３４がスプリング３９を圧縮
しつつダイヤフラム３４を左方へと偏位させ、バルブ３
５が大気パイプ４０を塞ぎ、負圧通路３６が開く。する
と、吸気管負圧により負圧通路３６を介してスプリング
室３７の空気が吸入されダイヤフラム１８は右方へと偏
位され、弁体２３ｄ、空気流出口２１を遮断し、２次空
気は連通口２２を通って第２圧力室１７、開口３１へと
ダイハートされる。この状態より再び負荷まだはエンジ
ン回転が低下すると、ダイヤプラム室３８の圧力が「が
り、ダイヤフラム３４は右動しバルブ３６は負圧通路３
６を閉じ大気パイプ４０よりスプリング室３７には大気
が導かれて弁体２３は左方へと作動され連通口２２は閉
成されて再びインジエク７ヨン状態となる。In FIG. 7, the signal extraction tube 25 is provided with an intake pipe negative pressure control valve 33. In the low-medium speed and low-medium load range, the pressure P+ in the first pressure chamber 16 is low and the diaphragm 34 of the control valve 33 can still be operated, and the valve 35 closes the negative pressure passage 36 from the intake pipe. Atmospheric air is guided into the spring chamber 37, and the diaphragm 18 is pushed to the left and the valve body 2
3 blocks the communication port 22, and the secondary air is sent to the exhaust system and is in an injection state. When the load or engine rotation becomes negative and reaches a high load/high speed range, pressure P3 increases,
'+l1ll i++ The pressure in the diaphragm chamber 38 of the valve 33 also increases, and the diaphragm 34 compresses the spring 39 while deflecting the diaphragm 34 to the left.
5 closes the atmospheric pipe 40, and the negative pressure passage 36 opens. Then, the air in the spring chamber 37 is sucked in through the negative pressure passage 36 due to the negative pressure in the intake pipe, and the diaphragm 18 is deflected to the right, blocking the valve body 23d and the air outlet 21, and allowing the secondary air to communicate. It is die-hardened through the opening 22 to the second pressure chamber 17 and the opening 31 . When the engine speed decreases again from this state, the pressure in the diaphragm chamber 38 decreases, the diaphragm 34 moves to the right, and the valve 36 opens the negative pressure passage 3.
6 is closed, atmospheric air is introduced into the spring chamber 37 from the atmospheric pipe 40, the valve body 23 is actuated to the left, the communication port 22 is closed, and the injector is in the injected state again.
まだ、第・８図の実施例においては、信号取出チューブ
２５をプレッシャースイッチ４１に接続すると共に、プ
レッシャースイッチ４１によりＯＮ 。However, in the embodiment shown in FIG. 8, the signal extraction tube 25 is connected to the pressure switch 41, and the pressure switch 41 is turned on.
ＯＦ下副制御れスプリング室３７に吸気管負圧才だは大
気を導＜：つ方ルノイド弁４２を設けて、スプリング室
３７に吸気管負圧捷だは大気を切換えて導くようにして
ダイヤフラム１８及び弁体２３を作動し２次空気を制御
するものである。A diaphragm valve 42 is provided to guide the intake pipe negative pressure or the atmosphere into the spring chamber 37 under the OF lower sub-control, and to switch between the intake pipe negative pressure and the atmosphere to guide the spring chamber 37. 18 and the valve body 23 to control the secondary air.
上記、２つの実施例においては、信号取出チューブ２５
の圧力信号ないし圧力Ｐ３が変動しても、吸気管負圧制
御弁３３およびプレッシャースイッチ４１には、通常ヒ
ステリンスがあり、第９図に示すようなヒステリンスル
ープを描き、圧力幅（１においては弁体２３が作動され
ることのない不動域が形成される。まだ、吸気管負圧と
いう、２次空気とは全く別系統のより安定した信号によ
り弁体２３を作動しているだめより安定した制御ができ
る。更に、上述し７だような不動域が存在し制御弁３３
、プレツ／ヤースイッチ４１のダイヤフラム室３８．４
３圧力変化は、ディレィバルブ４４の絞りオリフィス４
５と１方向弁４６との作用によりおだやかな変化される
ため、第１０図実線で示す圧力Ｐ３変動に対して破線の
ごとき動特性を示ス。このだめ、弁体２３のＰ３変動に
伴うチャタリングの発生は完全に防止される。In the above two embodiments, the signal extraction tube 25
Even if the pressure signal or pressure P3 fluctuates, the intake pipe negative pressure control valve 33 and the pressure switch 41 usually have hysteresis, and a hysterin loop as shown in FIG. 9 is drawn, and the pressure width (in 1) A stationary region is formed in which the valve body 23 is not operated.It is still more stable than if the valve body 23 was operated by a more stable signal called intake pipe negative pressure, which is completely different from the secondary air. In addition, there is a stationary region such as 7 mentioned above, and the control valve 33
, diaphragm chamber 38.4 of prez/ya switch 41
3 The pressure change is caused by the throttle orifice 4 of the delay valve 44.
5 and the one-way valve 46, the pressure P3 exhibits dynamic characteristics as shown by the broken line with respect to the fluctuation of the pressure P3 shown by the solid line in FIG. As a result, the occurrence of chattering due to P3 fluctuation of the valve body 23 is completely prevented.
以上の説明より明らかなように本発明によれば、内燃機
関の高負荷・高速運転時にのみ排気系への２次空気の供
給を確実に遮断でき、排気ガスの悪化を招くことなく、
排気系の過熱による熱害等を防止することができ、しか
も構造簡単にして安価に提供できる等の優れた効果を発
揮することができる。As is clear from the above description, according to the present invention, it is possible to reliably cut off the supply of secondary air to the exhaust system only when the internal combustion engine is operating under high load and at high speed, without causing deterioration of exhaust gas.
It is possible to prevent heat damage caused by overheating of the exhaust system, and it is also possible to exhibit excellent effects such as being able to simplify the structure and provide it at low cost.
第１図は従来の２次空気制御装置を示す概略断面図、第
２図は第１図の装置による２次空気制御を説明するグラ
フ、第３図は本発明に係る装置を有する内燃機関の一実
施例を示す全体概略系統図、第４図、第５図は第３図の
２次空気制御装置の各部の圧力値を示すグラフ、第６図
は同装置による２次空気制御を説明するグラフ、第７図
は本発明の他の実施例を示す概略断面図、第８図は本発
明の別の実施例を示す概略断面図、第９図は第７図ない
し第８図の装置の静的作動特性を示すグラフ、第１０図
は同装置の動的作動特性を示すグラフである。
図中、１はエンジン本体、３は吸気マニホルド、４は排
気マニホルド、５はニーアポ７プ、６は吸気％燕蕃台嬌
蘂、８は２次空気供給通路、１０は逆止弁、１３は２次
空気制御装置、１６は第１川力室、１７は第２圧力室、
１８はダイヤフラム、１９はダイヤフラム室、２０は空
気流入口、２１は空気流出口、２２は連通口、２３は弁
体、２４は弁棒、２５は信号取出チューブ、２８は圧力
調整オリフィス、２９はリーク通路、３０はリーク調整
オリフィス、３１は開口、３３は吸気管負圧制御弁、３
４はダイヤフラム、３６は負圧通路、３７はスプリング
室、３８はダイヤフラム室、４０は大気パイプ、４１は
プレッ／ヤースイッチ、４２は；３方ソレノイド弁、Ｐ
ｉ ＋ Ｐ ２ ＋ Ｐ ３は圧力である。
特許出願人 いすソ自動車株式会社
代理人弁理士 絹 谷 信 雄
第１図
第２図
イヘー 、 −高エンシン
回昧
第７図
第９図
休−仄ｈ −高
第１０図
ヂρ（Ｉ −−
ルー Ａう苛 −尺FIG. 1 is a schematic sectional view showing a conventional secondary air control device, FIG. 2 is a graph explaining secondary air control by the device in FIG. 1, and FIG. 3 is an internal combustion engine equipped with the device according to the present invention. An overall schematic system diagram showing one embodiment, Figures 4 and 5 are graphs showing pressure values of each part of the secondary air control device in Figure 3, and Figure 6 explains secondary air control by the device. 7 is a schematic sectional view showing another embodiment of the present invention, FIG. 8 is a schematic sectional view showing another embodiment of the present invention, and FIG. 9 is a schematic sectional view of the apparatus shown in FIGS. 7 to 8. FIG. 10 is a graph showing the static operating characteristics, and FIG. 10 is a graph showing the dynamic operating characteristics of the device. In the figure, 1 is the engine body, 3 is the intake manifold, 4 is the exhaust manifold, 5 is the knee pop-up, 6 is the intake percentage, 8 is the secondary air supply passage, 10 is the check valve, and 13 is the Secondary air control device, 16 is the first river pressure chamber, 17 is the second pressure chamber,
18 is a diaphragm, 19 is a diaphragm chamber, 20 is an air inlet, 21 is an air outlet, 22 is a communication port, 23 is a valve body, 24 is a valve stem, 25 is a signal extraction tube, 28 is a pressure adjustment orifice, 29 is a Leak passage, 30 is a leak adjustment orifice, 31 is an opening, 33 is an intake pipe negative pressure control valve, 3
4 is a diaphragm, 36 is a negative pressure passage, 37 is a spring chamber, 38 is a diaphragm chamber, 40 is an atmospheric pipe, 41 is a pressure/ear switch, 42 is a three-way solenoid valve, P
i + P 2 + P 3 is pressure. Patent Applicant Isuso Jidosha Co., Ltd. Representative Patent Attorney Nobuo Kinutani Figure 1 Figure 2 Ihe, - High Enshin Kai Figure 7 Figure 9 Shu - 组h - High Figure 10 ヂρ (I - - Lou A urai - shaku
Claims (1)
る２次空気供給通路の２次空気量を制ｍｌする２次空気
制御装置において、上記２次空気供給通路に介設された
第１圧力室と、該第１圧力室に連通口を介して連通接続
され大気開放のだめの開口を有する第２圧力室と、上記
第１圧力室の圧力信号を取り出すべく、第１圧力室に接
続された信号取出チューブと、該チューブ 内の空気を
上記第２圧力室にリークすべく、第２圧力室と信号取出
チューブとの間に介設されたリーク通路と、上記信号取
出チューブの圧力信号に応じて上記連通口と一ヒ記第１
圧力室に流入した空気を上記排気系に導くだめの空気流
出口とを開閉作動する開閉作動手段とを備えだことを特
徴とする内燃機関の２次空気制御装置。 ２ 上記信号取出チューブが流計調整のオリフィスを有
することを特徴とする特許 囲第１項記載の内燃機関の２次空気制御装置。 ３ −ヒ記すーク通路がそのリーク量を調整するだめの
オリフィスを有することを特徴とする上記特許請求の範
囲第１項乃至第２項記載の内燃機関の２次空気制御装置
。[Scope of Claims] 1. In a secondary air control device that controls the amount of secondary air in a secondary air supply passage that supplies air discharged from an air pop to an exhaust system, a first pressure chamber that is connected to the first pressure chamber through a communication port and has an opening for venting to the atmosphere; a signal extraction tube connected to the signal extraction tube, a leak passage interposed between the second pressure chamber and the signal extraction tube to leak air in the tube to the second pressure chamber, and a signal extraction tube connected to the signal extraction tube. According to the pressure signal, the communication port and
A secondary air control device for an internal combustion engine, comprising an opening/closing means for opening/closing an air outlet for guiding air flowing into the pressure chamber to the exhaust system. 2. The secondary air control device for an internal combustion engine as set forth in paragraph 1 of the patent specification, characterized in that the signal extraction tube has an orifice for flow meter adjustment. 3. The secondary air control device for an internal combustion engine according to claims 1 and 2, wherein the soak passage has an orifice for adjusting the amount of leakage thereof.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3152982A JPS5910723A (en) | 1982-02-27 | 1982-02-27 | Secondary air control device for internal-combustion engine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3152982A JPS5910723A (en) | 1982-02-27 | 1982-02-27 | Secondary air control device for internal-combustion engine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS5910723A true JPS5910723A (en) | 1984-01-20 |
Family
ID=12333718
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3152982A Pending JPS5910723A (en) | 1982-02-27 | 1982-02-27 | Secondary air control device for internal-combustion engine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5910723A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0433691A1 (en) * | 1989-11-22 | 1991-06-26 | Siemens Aktiengesellschaft | Combined air flow control and check valve |
-
1982
- 1982-02-27 JP JP3152982A patent/JPS5910723A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0433691A1 (en) * | 1989-11-22 | 1991-06-26 | Siemens Aktiengesellschaft | Combined air flow control and check valve |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3906723A (en) | Exhaust gas purifying system | |
| US3921396A (en) | Exhaust gas purification system | |
| US4085586A (en) | Secondary air supply system for internal combustion engines | |
| US4437311A (en) | Apparatus for controlling the flow of exhaust gas in an internal combustion engine with a turbocharger and a catalytic converter | |
| US3888080A (en) | Air flow control valve | |
| US4257227A (en) | Secondary air controlling apparatus for internal combustion engines | |
| US4070830A (en) | Integral air switching diverter valve | |
| US4163434A (en) | Air-fuel ratio regulator for internal combustion engine | |
| US5375579A (en) | Evaporated fuel controller | |
| US4098241A (en) | Apparatus for preventing after-fire in an internal combustion engine | |
| JPS5910723A (en) | Secondary air control device for internal-combustion engine | |
| US4270347A (en) | Exhaust gas purification system for an internal combustion engine | |
| US3591961A (en) | Air pump flow control valve for engine exhaust emission control system | |
| US4177641A (en) | Apparatus for cleaning exhaust gas for an internal combustion engine | |
| US4202173A (en) | Secondary air supplying device of an internal combustion engine | |
| US5509397A (en) | Air supply system preventing backflow | |
| CA1108996A (en) | Power cruise diverter valve | |
| US4177642A (en) | Diverter valve for exhaust system of internal combustion engine | |
| JPS5911723B2 (en) | Secondary air control device for internal combustion engine exhaust system | |
| US4148189A (en) | Exhaust gas purifying system for engines | |
| US4147032A (en) | Secondary air supply control system | |
| US4104880A (en) | Exhaust gas purifying system having a diaphragm type control valve | |
| US4164207A (en) | Exhaust gas recirculation means | |
| CA1188940A (en) | Constant pressure relief valve for an air control valve | |
| CN100520039C (en) | Fuel supply limiter for carburetor |