JPS6148619B2 - - Google Patents
Info
- Publication number
- JPS6148619B2 JPS6148619B2 JP17220780A JP17220780A JPS6148619B2 JP S6148619 B2 JPS6148619 B2 JP S6148619B2 JP 17220780 A JP17220780 A JP 17220780A JP 17220780 A JP17220780 A JP 17220780A JP S6148619 B2 JPS6148619 B2 JP S6148619B2
- Authority
- JP
- Japan
- Prior art keywords
- intake
- throttle valve
- engine
- negative pressure
- idling
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000007906 compression Methods 0.000 description 8
- 230000006835 compression Effects 0.000 description 7
- 239000000446 fuel Substances 0.000 description 6
- 238000002347 injection Methods 0.000 description 6
- 239000007924 injection Substances 0.000 description 6
- 239000000779 smoke Substances 0.000 description 6
- 238000002485 combustion reaction Methods 0.000 description 4
- 230000007423 decrease Effects 0.000 description 4
- 230000000994 depressogenic effect Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 2
- 230000001133 acceleration Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001934 delay Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
Landscapes
- Control Of Throttle Valves Provided In The Intake System Or In The Exhaust System (AREA)
Description
【発明の詳細な説明】
本発明は、デイーゼル機関のアイドリング又は
アイドリング乃至低負荷運転域での静粛性を向上
すると共に、機関の減速時におけるスモークの発
生を低減することを目的とする吸気制御装置に関
するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention provides an air intake control device that aims to improve the quietness of a diesel engine during idling or in the idling to low-load operating range, and to reduce the occurrence of smoke when the engine decelerates. It is related to.
一般にデイーゼル機関においては、機関への吸
入空気の絞り制御を行なうことなく、燃料噴射量
の増減操作によつて機関出力の調節を行なつてい
る。従つてこのデイーゼル機関への吸入空気は、
機関の運転状態とは無関係に常に大気解放のまゝ
燃焼室に導入されるので、アイドリング又はアイ
ドリング乃至低負荷運転での吸入空気量が多くな
りすぎ圧縮圧力が高く、これに伴う着火後の最高
圧力の上昇及び圧力の高い上昇率等によつて燃焼
騒音及び振動が高くなるのであつた。 In general, in a diesel engine, the engine output is adjusted by increasing or decreasing the amount of fuel injection, without controlling the intake air to the engine. Therefore, the intake air to this diesel engine is
Since the air is always introduced into the combustion chamber while being open to the atmosphere, regardless of the operating state of the engine, the amount of intake air becomes too large during idling or low-load operation, resulting in high compression pressure and the resulting maximum after ignition. Combustion noise and vibration increased due to the increase in pressure and the high rate of increase in pressure.
そこでこの問題を解決するため最近ではアイド
リング又はアイドリング乃至低負荷域において機
関への吸入空気量を絞ることが提案されている。
この吸気絞りにより、圧縮圧力が下がり、圧縮行
程中の角速度の低下が少なくなると共に、膨張行
程では最大圧力が減少するため回転力が小さくな
り角速度を加速する割合が低減し、圧縮、膨張行
程におけるクランク軸の角速度変動が少なくなる
から、機関の振動が低減する。更に適当な吸気絞
りは、圧縮終り温度を高める。デイーゼル機関で
は圧縮終り温度が高い程、着火遅れが少なくなつ
て燃焼が静粛になる。 In order to solve this problem, it has recently been proposed to throttle the amount of air taken into the engine during idling or in the idling or low load range.
This intake throttle reduces the compression pressure and reduces the drop in angular velocity during the compression stroke, and also reduces the maximum pressure during the expansion stroke, reducing the rotational force and reducing the rate of acceleration of the angular velocity during the compression and expansion strokes. Since the angular velocity fluctuation of the crankshaft is reduced, engine vibration is reduced. Furthermore, suitable intake throttling increases the end-of-compression temperature. In a diesel engine, the higher the compression end temperature, the less the ignition delay and the quieter the combustion.
しかし、アイドリング又はアイドリング乃至低
負荷域での吸気絞りを行なうデイーゼル機関にお
いて、吸気を絞り過ぎた場合（例えば機関の減速
時に絞り弁が閉じた状態で機関回転が行くなつた
場合など）においては、実圧縮比の低下により圧
縮絞り温度が下がり、燃焼が遅れて白煙乃至黒煙
等のスモークが発生するばかりか、着火が不安定
になり振動及び騒音が逆に増大することになる。 However, in a diesel engine that throttles the intake air during idling or in the idling or low load range, if the intake air is throttled too much (for example, when the engine slows down with the throttle valve closed when the engine is decelerating), As the actual compression ratio decreases, the compression orifice temperature decreases, which not only delays combustion and generates smoke such as white smoke or black smoke, but also causes ignition to become unstable and conversely increases vibration and noise.
本発明は、このようにアイドリング又はアイド
リング乃至低負荷域における吸気絞り手段を備え
たデイーゼル機関において、吸気絞り時に吸気管
負圧が異常に大きくなれば、絞り弁に対して設け
た吸気管負圧調節手段にて絞り弁を開いて吸気管
負圧を調整することにより、デイーゼル機関に吸
気絞りを適用した場合の問題を効果的に解消した
ものである。 The present invention provides that in a diesel engine equipped with an intake throttling means during idling or in a low load range, if the intake pipe negative pressure becomes abnormally large during intake throttling, the intake pipe negative pressure provided for the throttle valve is reduced. By opening the throttle valve using the adjusting means and adjusting the negative pressure in the intake pipe, the problem that occurs when an intake throttle is applied to a diesel engine is effectively solved.
以下本発明を第１図に示す第１実施例について
説明すると、図において１はデイーゼル機関（図
示せず）への吸気通路、２は機関に附属の燃料噴
射ポンプ、３はアクセルペダル、４は前記燃料噴
射ポンプ２における燃料噴射量調節用のコントロ
ールレバーでワイヤー５等を介して前記アクセル
ペダル３と連動させてある。前記吸気通路１に
は、弁軸６の回動によつて当該通路１を開閉する
ようにしたバタフライ式の絞り弁７を設け、該絞
り弁７の弁軸６に固着したレバー８をロツド９を
介してダイヤフラム式アクチエータ１０における
ダイヤフラム１１に連結してダイヤフラム室１２
内のばね１３にて絞り弁７を全開状態に押圧付勢
する。 The first embodiment of the present invention shown in FIG. 1 will be described below. In the figure, 1 is an intake passage to a diesel engine (not shown), 2 is a fuel injection pump attached to the engine, 3 is an accelerator pedal, and 4 is an intake passage to a diesel engine (not shown). A control lever for adjusting the fuel injection amount in the fuel injection pump 2 is linked to the accelerator pedal 3 via a wire 5 or the like. The intake passage 1 is provided with a butterfly type throttle valve 7 which opens and closes the passage 1 by rotating the valve stem 6, and a lever 8 fixed to the valve stem 6 of the throttle valve 7 is connected to a rod 9. The diaphragm chamber 12 is connected to the diaphragm 11 in the diaphragm actuator 10 via the
The inner spring 13 presses and urges the throttle valve 7 to a fully open state.
また、図中符号１４はダイヤフラム式の負圧切
換弁を示し、該切換弁１４内における連通路１５
には、これを切換弁１４内における大気連通室１
６に開口するポート１７を設け、切換弁１４に大
気連通室１６とダイヤフラム室を区成するように
取付けたダイヤフラム１８には前記ポート１７を
開閉するフラツプ１８′を設け、ダイヤフラム室
１９内のばね２０にてフラツプ１８′をポート１
７に対して常閉方向に押圧付勢し、ダイヤフラム
室１９を、前記吸気通路１において絞り弁７より
下流側（機関側）に設けたポート２１に負圧取出
通路２２を介して接続し、切換弁１４における連
通路１５の一端を通路２３を介して前記アクチエ
ータ１０のダイヤフラム室１２に接続する一方、
他端を機関に連動するバキユームポンプ２４等の
真空源に通路２５を介して接続し、該通路２５中
に設けた電磁弁２６とバツテリー２７とをつなぐ
配線２８中には、前記コントロールレバー４又は
アクセルペダル３をアイドリング又はアイドリン
グ乃至低負荷域の位置にしたときONとなつて、
電磁弁２６が開くようにしたスイツチ２９を設け
て成るものである。 Further, reference numeral 14 in the figure indicates a diaphragm type negative pressure switching valve, and a communication passage 15 in the switching valve 14.
In this case, this is connected to the atmosphere communication chamber 1 in the switching valve 14.
A diaphragm 18 attached to the switching valve 14 to separate the atmosphere communication chamber 16 and the diaphragm chamber is provided with a flap 18' for opening and closing the port 17. At 20, connect flap 18' to port 1.
7 in the normally closed direction, and connects the diaphragm chamber 19 to a port 21 provided on the downstream side (engine side) of the throttle valve 7 in the intake passage 1 via a negative pressure extraction passage 22, One end of the communication passage 15 in the switching valve 14 is connected to the diaphragm chamber 12 of the actuator 10 via the passage 23,
The other end of the control lever 4 is connected to a vacuum source such as a vacuum pump 24 linked to the engine via a passage 25, and a wiring 28 connecting a solenoid valve 26 provided in the passage 25 and a battery 27 includes the control lever 4. Or it turns ON when the accelerator pedal 3 is in the idling or idling to low load range position,
A switch 29 is provided to open the solenoid valve 26.
この構成において、アクセルペダル３をアイド
リング又は低負荷運転域以上に踏み込んだ状態で
は、配線２８中のスイツチ２９がOFFで電磁弁
２６が閉じることにより、アクチエータ１０のダ
イヤフラム室１２には真空が作用せず、従つて絞
り弁７はダイヤフラム室１２内のばね１３にて全
開に保持されるから、機関への吸入空気の絞り制
御は行なわれないが、アクセルペダル３を踏まな
いか少しだけ踏んだ状態では、配線２８中のスイ
ツチ２９がONになつて電磁弁２６が開くことに
より、アクチエータ１０のダイヤフラム室１２に
真空圧が作用し、この真空圧でダイヤフラム１１
がばね１３に抗してダイヤフラム室１２内に引込
まれ、これに連動する絞り弁７が全閉となるか
ら、機関への吸入空気は、アイドリング又はアイ
ドリング乃至低負荷域において絞り制御されるの
である。 In this configuration, when the accelerator pedal 3 is depressed beyond the idling or low-load operating range, the switch 29 in the wiring 28 is turned OFF and the solenoid valve 26 is closed, so that a vacuum is not applied to the diaphragm chamber 12 of the actuator 10. Therefore, since the throttle valve 7 is held fully open by the spring 13 in the diaphragm chamber 12, the intake air to the engine is not throttled, but when the accelerator pedal 3 is not depressed or only slightly depressed. Now, when the switch 29 in the wiring 28 is turned on and the solenoid valve 26 is opened, vacuum pressure acts on the diaphragm chamber 12 of the actuator 10, and this vacuum pressure causes the diaphragm 11 to open.
is drawn into the diaphragm chamber 12 against the spring 13, and the throttle valve 7 linked thereto is fully closed, so that the intake air to the engine is throttle-controlled at idling or in the idling to low load range. .
この吸気絞りの状態で、絞り弁７以降の吸気管
負圧が一定以上に大きくなると、この負圧は切換
弁１４におけるダイヤフラム室１９に作用し、ダ
イヤフラム１８がばね２０に抗して後退してポー
ト１７が開くから、連通路１５にはポート１７か
ら大気が吸い込まれ、連通路１５の真空圧つまり
アクチエータ１０におけるダイヤフラム室１２の
真空圧は小さくなり、大気圧と真空源の真空圧と
の合成真空圧力になることにより、絞り弁７は全
閉の状態からこの合成真空圧に見合う所まで開い
て、吸入空気量が増大するから吸気管負圧が一定
以上に大きくなることが防止され、吸気絞り状態
での吸気管負圧が一定以上に大きくならないよう
に制御できるのである。 In this state of intake throttling, when the negative pressure in the intake pipe after the throttle valve 7 becomes greater than a certain level, this negative pressure acts on the diaphragm chamber 19 in the switching valve 14, causing the diaphragm 18 to retreat against the spring 20. Since the port 17 is open, the atmosphere is sucked into the communication path 15 from the port 17, and the vacuum pressure in the communication path 15, that is, the vacuum pressure in the diaphragm chamber 12 in the actuator 10, decreases, and the combination of the atmospheric pressure and the vacuum pressure of the vacuum source decreases. By creating a vacuum pressure, the throttle valve 7 opens from a fully closed state to a point corresponding to this synthetic vacuum pressure, increasing the amount of intake air, preventing the intake pipe negative pressure from increasing beyond a certain level, and reducing the intake pressure. This makes it possible to control the intake pipe negative pressure in the throttled state so that it does not exceed a certain level.
第２図及び第３図は第２の実施例であり、この
図において機関への吸気通路１中に設けたバタフ
ライ式絞り弁７における弁軸６は、吸気通路１の
中心から適宜寸法ｅだけずれた偏芯位置に設けら
れ、この弁軸６の通路外側端部には、レバー８′
を回動自在に被嵌すると共に該レバー８′の側面
に接当するストツパー３０を固着し、該ストツパ
ー３０とレバー８′との間にはストツパー３０を
レバー８′に常時接当するように付勢するねじり
ばね３１を弁軸６に被嵌して設ける一方、レバー
８′をロツド９を介してダイヤフラム式のアクチ
エータ１０のダイヤフラム１１に連結してダイヤ
フラム室１２内のばね１３にて絞り弁７を全開状
態に押圧付勢し、そのダイヤフラム室１２と機関
に附属のバキユームポンプ１４等の真空源とを接
続する通路２５中に電磁弁２６を設け、該電磁弁
２６とバツテリー２７とをつなぐ配線２８中に
は、燃料噴射ポンプ２のコントロールレバー４又
はアクセルペダル３をアイドリング又はアイドリ
ング乃至低負荷域の位置にしたときONとなつ
て、電磁弁２６が開くようにしたスイツチ２９を
設けて成るものである。 2 and 3 show a second embodiment, and in these figures, the valve stem 6 of the butterfly throttle valve 7 provided in the intake passage 1 to the engine is located at an appropriate distance e from the center of the intake passage 1. A lever 8' is provided at an eccentric position, and a lever 8' is provided at the outer end of the passage of the valve shaft 6.
A stopper 30 is fixedly attached to the lever 8' so that the lever 8' is rotatably fitted thereto and abuts against the side surface of the lever 8'. A biasing torsion spring 31 is fitted onto the valve stem 6, and the lever 8' is connected to the diaphragm 11 of the diaphragm actuator 10 via the rod 9, so that the spring 13 in the diaphragm chamber 12 operates the throttle valve. A solenoid valve 26 is provided in a passage 25 connecting the diaphragm chamber 12 and a vacuum source such as a vacuum pump 14 attached to the engine, and the solenoid valve 26 and battery 27 are The connecting wiring 28 is provided with a switch 29 which is turned on and opens the solenoid valve 26 when the control lever 4 or accelerator pedal 3 of the fuel injection pump 2 is placed in the idling or idling or low load range position. It is what it is.
この第２の実施例において、アクセルペダル３
を踏み込んだ状態では電磁弁２６は閉となるの
で、絞り弁７は全開で、吸気の絞り制御は行なわ
れないが、アクセルペダル３を踏まないか、少し
踏んだ状態にすると、電磁弁２６が開きアクチエ
ター１０のダイヤフラム室１２に真空圧が作用す
るので絞り弁７はこの真空圧によつて２点鎖線で
示すように全閉となつて、アイドリング又はアイ
ドリング乃至低負荷域における吸気絞り制御が行
なわれる。この吸気絞りの状態では、吸気管負圧
の全圧が偏芯軸の絞り弁７に対して矢印Ａ方向つ
まり絞り弁７を開ける方向に作用する。そしてこ
の全圧が吸気管負圧に比例し、吸気管負圧が一定
以上に大きくなると、絞り弁７は前記全圧によつ
てねじりばね１３に抗して、全閉の状態からねじ
ばね力と全圧とが釣り合う所まで開くから、吸気
管負圧が一定以上に大きくなることが防止され、
吸気絞り状態での吸気管負圧が一定以上に大きく
ならないように制御できるのであり、この第２実
施例は前記第１実施例における負圧切換弁１４を
必要としないから、構造が極めて簡単で且つ故障
が少なくて信頼性が高い。 In this second embodiment, the accelerator pedal 3
When the accelerator pedal 3 is depressed, the solenoid valve 26 is closed, so the throttle valve 7 is fully open and no intake throttle control is performed. Since vacuum pressure acts on the diaphragm chamber 12 of the opening actuator 10, the throttle valve 7 is fully closed as shown by the two-dot chain line due to this vacuum pressure, and intake throttle control is performed at idling or in the idling to low load range. It can be done. In this intake throttle state, the total intake pipe negative pressure acts on the throttle valve 7 on the eccentric axis in the direction of arrow A, that is, in the direction in which the throttle valve 7 is opened. This total pressure is proportional to the negative pressure in the intake pipe, and when the negative pressure in the intake pipe becomes larger than a certain level, the throttle valve 7 resists the torsion spring 13 due to the total pressure, and changes from the fully closed state to the screw spring force. Since it opens until the intake pipe and total pressure are balanced, the intake pipe negative pressure is prevented from increasing beyond a certain level.
It is possible to control the intake pipe negative pressure in the intake throttled state so that it does not exceed a certain level, and since this second embodiment does not require the negative pressure switching valve 14 in the first embodiment, the structure is extremely simple. In addition, there are few failures and high reliability.
また、本発明は、絞り弁の閉位置において、当
該絞り弁を吸気管負圧に応動して開閉する手段と
しては、前記２の実施例に限らず、他の手段を用
いて、閉状態の絞り弁を吸気管負圧に応動して開
閉するようにしても良いのである。 Furthermore, the present invention is not limited to the second embodiment described above, and uses other means to open and close the throttle valve in response to intake pipe negative pressure when the throttle valve is in the closed position. The throttle valve may be opened and closed in response to intake pipe negative pressure.
以上の通り本発明は、アイドリング又はアイド
リング乃至低負荷域における吸気絞り手段を備え
たデイーゼル機関において、吸気絞り状態の絞り
弁を、吸気管負圧が大きくなるとこれに応じて開
くことにより吸気管負圧が一定以上に大きくなら
ないように制御するものであるから、吸気の絞り
過ぎによるスモークの発生及び振動、騒音の増大
を防止できて、吸気絞りによる不具合を解消でき
るのである。 As described above, in a diesel engine equipped with an intake throttle means during idling or in a low load range, the present invention opens a throttle valve in an intake throttle state in response to an increase in intake pipe negative pressure. Since the pressure is controlled so that it does not exceed a certain level, it is possible to prevent the generation of smoke and increase in vibration and noise due to excessive restriction of the intake air, thereby eliminating problems caused by the restriction of the intake air.
また、吸気絞り制御時における吸気管負圧の増
大は、機関の減速時とアイドリング時とでは大き
く相違し、減速時における吸気管負圧の増大は大
きいから、その大きな吸気管負圧の増大を防止す
るには多量の空気を導入しなければならないが、
本発明は前記のように絞り弁を開いて大気を導入
するものであるから、絞り弁の開によつて多量の
大気を導入でき、従つて機関の減速に際しても吸
気管負圧の増大を適確に防止でき、換言すれば機
関の急激な減速に対しても、スモークの発生及び
振動、騒音の増大を確実に防止できる効果を有す
る。 In addition, the increase in intake pipe negative pressure during intake throttle control differs greatly between when the engine is decelerating and when the engine is idling, and the increase in intake pipe negative pressure during deceleration is large. To prevent this, a large amount of air must be introduced,
Since the present invention introduces atmospheric air by opening the throttle valve as described above, a large amount of atmospheric air can be introduced by opening the throttle valve, and therefore, even when the engine is decelerated, the increase in intake pipe negative pressure can be appropriately controlled. In other words, it has the effect of reliably preventing the generation of smoke and the increase in vibration and noise even when the engine suddenly decelerates.
第１図は本発明の第１実施例を示す図、第２図
は本発明の第２実施例を示す図、第３図は第２図
の−視断面図である。
２……燃料噴射ポンプ、３……アクセルペダ
ル、１……吸気通路、７……絞り弁、６……弁
軸、１０……アクチエータ。
FIG. 1 is a diagram showing a first embodiment of the invention, FIG. 2 is a diagram showing a second embodiment of the invention, and FIG. 3 is a cross-sectional view taken from - in FIG. 2. 2... Fuel injection pump, 3... Accelerator pedal, 1... Intake passage, 7... Throttle valve, 6... Valve shaft, 10... Actuator.
Claims (1)
機関のアイドリング又はアイドリング乃至低負荷
域において閉じ、これ以外の負荷域において大き
く開くようにした絞り弁を設け、該絞り弁には、
その閉位置において当該絞り弁を吸気管負圧に応
じて開閉する手段を設けたことを特徴とするデイ
ーゼル機関の吸気制御装置。1 In a diesel engine, in its intake passage,
A throttle valve is provided that closes when the engine is idling or in a low load range and opens wide in other load ranges, and the throttle valve includes:
An intake control device for a diesel engine, comprising means for opening and closing the throttle valve in its closed position in response to intake pipe negative pressure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17220780A JPS5797033A (en) | 1980-12-05 | 1980-12-05 | Intake control apparatus of diesel engine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17220780A JPS5797033A (en) | 1980-12-05 | 1980-12-05 | Intake control apparatus of diesel engine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5797033A JPS5797033A (en) | 1982-06-16 |
| JPS6148619B2 true JPS6148619B2 (en) | 1986-10-24 |
Family
ID=15937567
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17220780A Granted JPS5797033A (en) | 1980-12-05 | 1980-12-05 | Intake control apparatus of diesel engine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5797033A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS646334U (en) * | 1987-07-01 | 1989-01-13 | ||
| KR101896785B1 (en) * | 2016-10-18 | 2018-09-07 | 현대자동차주식회사 | Apparatus and method for flow generated noise reduction of vehicle engine |
-
1980
- 1980-12-05 JP JP17220780A patent/JPS5797033A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5797033A (en) | 1982-06-16 |
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