JPH08303250A - Intake device for internal combustion engine - Google Patents
Intake device for internal combustion engineInfo
- Publication number
- JPH08303250A JPH08303250A JP7108363A JP10836395A JPH08303250A JP H08303250 A JPH08303250 A JP H08303250A JP 7108363 A JP7108363 A JP 7108363A JP 10836395 A JP10836395 A JP 10836395A JP H08303250 A JPH08303250 A JP H08303250A
- Authority
- JP
- Japan
- Prior art keywords
- intake
- port
- intake port
- control valve
- intake 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
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
- F02B2275/00—Other engines, components or details, not provided for in other groups of this subclass
- F02B2275/48—Tumble motion in gas movement in cylinder
-
- 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
Landscapes
- Control Of Throttle Valves Provided In The Intake System Or In The Exhaust System (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、内燃機関の吸気装置に
関し、特に、所定の運転条件下で閉弁することにより吸
入空気の流れを制限してスワール等の筒内流を生成する
吸気制御弁を備えた内燃機関の吸気装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake device for an internal combustion engine, and more particularly to an intake control for closing a flow of intake air by closing a valve under a predetermined operating condition to generate an in-cylinder flow such as a swirl. The present invention relates to an intake device for an internal combustion engine equipped with a valve.
【０００２】[0002]
【従来の技術】近年、燃費や排気エミッション等の改善
のため、理論空燃比近傍よりも薄い空燃比で燃焼を行う
ようにした希薄燃焼機関（リーンバーンエンジン）が種
々提案されているが、かかる希薄燃焼を行う内燃機関で
は、混合気に占める燃料の割合が低いため、着火後の火
炎伝搬速度が遅く、燃焼が緩慢となる傾向がある。従っ
て、単に、混合気を希薄化しただけでは、燃焼状態が不
安定化し、運転性能が低下するおそれがあるため、例え
ば実開昭６３−１７８３０号公報等に開示されている如
く、一方のポート部に対応する切欠部が形成された吸気
制御弁を吸気通路内に設け、閉弁時には切欠部を介して
大部分の吸入空気を流通させることにより、シリンダ内
に適度なスワール（シリンダ内における吸気の主流に対
するシリンダ軸中心の周りを旋回する横渦流）、タンブ
ル（シリンダ内における吸気の主流に対するシリンダ軸
中心に直角方向の線の周りを旋回する縦渦流）を発生さ
せ、希薄燃焼時の燃焼安定性を図っている。2. Description of the Related Art In recent years, various lean-burn engines (lean-burn engines) have been proposed in which combustion is performed at an air-fuel ratio thinner than near the stoichiometric air-fuel ratio in order to improve fuel economy and exhaust emission. In an internal combustion engine that performs lean combustion, the proportion of fuel in the air-fuel mixture is low, so the flame propagation speed after ignition is low, and combustion tends to be slow. Therefore, if the air-fuel mixture is simply diluted, the combustion state may become unstable and the operating performance may deteriorate. For example, as disclosed in Japanese Utility Model Laid-Open No. 63-17830, one port An intake control valve with a notch corresponding to the section is provided in the intake passage, and most of the intake air is circulated through the notch when the valve is closed, so that an appropriate swirl (intake in the cylinder Of turbulence around the center axis of the cylinder) and tumble (longitudinal vortex that swirls around a line at right angles to the center of the cylinder axis relative to the main stream of intake air in the cylinder) to stabilize combustion during lean combustion. I am aiming for sex.
【０００３】そこで、かかる吸気制御弁を用いた従来技
術による内燃機関の吸気装置を図１０〜図１２に基づい
て説明すると、まず、図１０は、従来技術による内燃機
関の吸気装置の全体構成を示す構成説明図であって、シ
リンダ１は、図１１の断面図に示す如く、シリンダブロ
ック２に所定間隔で例えば４個、６個の如く複数個列設
され（１個のみ図示）、その内部にはピストン３が軸方
向（上下方向）に移動可能に設けられている。また、シ
リンダ１の上側を気液密に施蓋して設けられたシリンダ
ヘッド４とピストン３との間には例えば４弁ペントルー
フ型の燃焼室５が画成されており、この燃焼室５内に連
通するようにして、互いに対向する吸気ポート６と排気
ポート７とが、鋳造成形により、それぞれシリンダヘッ
ド４に一体的に形成されている。A conventional internal combustion engine intake system using such an intake control valve will be described with reference to FIGS. 10 to 12. First, FIG. 10 shows the overall structure of the conventional internal combustion engine intake system. FIG. 12 is a configuration explanatory view shown, in which, as shown in the sectional view of FIG. 11, a plurality of cylinders 1 are arranged in a cylinder block 2 at predetermined intervals, for example, 4 or 6 (only one is shown), and the inside thereof is shown. A piston 3 is provided in the shaft so as to be movable in the axial direction (vertical direction). A combustion chamber 5 of, for example, a four-valve pent roof type is defined between the cylinder head 4 and the piston 3 which are provided by covering the upper side of the cylinder 1 in a gas-liquid tight manner. An intake port 6 and an exhaust port 7 facing each other are formed integrally with the cylinder head 4 by casting.
【０００４】吸気ポート６は、図１０，図１１に示す如
く、その下流側が燃焼室５に向けて湾曲しつつ二股に分
岐して一対のタンブルポートをなす第１のポート部６
Ａ，第２のポート部６Ｂとなり、上流側の開口部６Ｃは
シリンダヘッド４の側面に開口し、全体として略Ｙ字状
に形成されている。また、前記排気ポート７も、その上
流側が燃焼室５に向けて湾曲しつつ二股に分岐して一対
の第１のポート部７Ａ，第２のポート部７Ｂとなり、下
流側の開口部７Ｃはシリンダヘッド４の側面で開口して
いる。そして、これら吸気ポート６，排気ポート７は、
図外の可変動弁機構等によって駆動される吸気弁８，排
気弁９を介して、その各ポート部６Ａ，６Ｂと各ポート
部７Ａ，７Ｂが所定のタイミングで燃焼室５と連通する
ようになっている。As shown in FIGS. 10 and 11, the intake port 6 has a first port portion 6 forming a pair of tumble ports by bifurcating while the downstream side thereof curves toward the combustion chamber 5.
A, the second port portion 6B, and the upstream side opening portion 6C is opened to the side surface of the cylinder head 4, and is formed in a substantially Y shape as a whole. The upstream side of the exhaust port 7 is also curved toward the combustion chamber 5 and bifurcated into a pair of a first port portion 7A and a second port portion 7B, and an opening 7C on the downstream side is a cylinder. The side surface of the head 4 is open. And these intake port 6 and exhaust port 7 are
Through the intake valve 8 and the exhaust valve 9 driven by a variable valve mechanism (not shown), the respective port portions 6A, 6B and the respective port portions 7A, 7B are communicated with the combustion chamber 5 at a predetermined timing. Has become.
【０００５】ここで、本明細書にいう「上流側」，「下
流側」とは、流体の流通方向における上流側，下流側を
それぞれ意味し、吸気ポート６では吸入空気の流入口た
る開口部６Ｃが上流側であり、排気ポート７では排気の
流出口たる開口部７Ｃが下流側となる。The terms "upstream side" and "downstream side" as used herein mean the upstream side and the downstream side, respectively, in the flow direction of the fluid, and the intake port 6 has an opening serving as an inlet of intake air. 6C is the upstream side, and in the exhaust port 7, the opening 7C that is the outlet of the exhaust is the downstream side.
【０００６】吸気通路１０は、その下流側の接続口１０
Ａが吸気ポート６の上流側開口部６Ｃに接続される一
方、その上流側は、吸気脈動を抑制するためのコレクタ
部を介して吸気集合通路（いずれも図示せず）に接続さ
れており、これら各シリンダ１毎に設けられた各吸気通
路１０と、コレクタ部と、吸気集合通路とによって吸気
マニホールド１１が構成されている。そして、吸気通路
１０の接続口１０Ａと吸気ポート６の上流側開口部６Ｃ
との接続箇所は、シリンダヘッド４の側面と略同一平面
上に位置する接続面１２となっている。The intake passage 10 has a connection port 10 on the downstream side thereof.
A is connected to the upstream opening 6C of the intake port 6, while its upstream side is connected to an intake collecting passage (neither is shown) via a collector portion for suppressing intake pulsation, An intake manifold 11 is configured by the intake passages 10 provided in each of the cylinders 1, the collector portion, and the intake collecting passages. The connection port 10A of the intake passage 10 and the upstream opening 6C of the intake port 6
The connection point with is a connection surface 12 that is located substantially on the same plane as the side surface of the cylinder head 4.
【０００７】また、吸気通路１０の接続口１０Ａの近傍
には吸入空気の流れを制御する吸気制御弁１３が設けら
れている。この吸気制御弁１３は、接続口１０Ａの近傍
に位置して吸気通路１０を横切るように挿通された弁軸
１３Ａと、弁軸１３Ａに取り付けられた略楕円板状の弁
体１３Ｂと、弁体１３Ｂの上側半分のうち吸気ポート６
の第１のポート部６Ａに対応した箇所を部分的に切り欠
いてなる切欠部１３Ｃとから、いわゆるバタフライ式開
閉弁として大略構成されており、前記切欠部１３Ｃは、
弁軸１３Ａの上側を寸法ｈだけオフセットして横方向に
切り欠いた水平部１３Ｃ1と、弁体１３Ｂの横幅方向の
略中心を通って水平部１３Ｃ1と直交するように上下方
向に切り欠かれた垂直部１３Ｃ2とを有している。An intake control valve 13 for controlling the flow of intake air is provided near the connection port 10A of the intake passage 10. This intake control valve 13 is located near the connection port 10A and is inserted so as to cross the intake passage 10, a valve body 13B having a substantially elliptical plate shape attached to the valve shaft 13A, and a valve body. Intake port 6 of the upper half of 13B
Is generally configured as a so-called butterfly type on-off valve from a notch 13C formed by partially notching a portion corresponding to the first port portion 6A, and the notch 13C is
A horizontal portion 13C 1 that is formed by offsetting the upper side of the valve shaft 13A by a dimension h and is cut out in the horizontal direction, and a vertical portion that is cut through in the horizontal direction of the valve body 13B and is orthogonal to the horizontal portion 13C 1 in the vertical direction. And a vertical portion 13C 2 which is cut.
【０００８】ここで、本明細書にいう「横方向」ないし
「横幅方向」とは、吸気ポート６の各ポート部６Ａ，６
Ｂの連設方向（各ポート部６Ａ，６Ｂが並ぶ方向）をい
い、シリンダ１の列設方向と略一致する。また、「上
側」，「下側」とは、原則として、機関本体の上側，下
側を意味し、特に、吸気制御弁１３について「上側」，
「下側」というときは、吸気制御弁１３が起立して吸気
通路１０を閉じたときの状態における上側，下側をい
う。The term "lateral direction" or "lateral width direction" as used herein means the port portions 6A, 6 of the intake port 6.
It refers to the continuous installation direction of B (the direction in which the port portions 6A and 6B are arranged side by side), and substantially coincides with the installation direction of the cylinders 1. In addition, “upper side” and “lower side” mean, in principle, the upper side and lower side of the engine body, and in particular, “upper side” and “lower side” of the intake control valve 13.
The term “lower side” refers to the upper side and the lower side in the state in which the intake control valve 13 is erected and the intake passage 10 is closed.
【０００９】そして、吸気制御弁１３は、その弁軸１３
Ａが図示せぬリンク等を介して吸気制御弁アクチュエー
タ１４に接続されており、この吸気制御弁アクチュエー
タ１４が後述するコントロールユニット１９からの制御
信号によって回転駆動することにより、起立して吸気通
路１０を閉じる閉弁状態と、略水平に倒れて吸気通路１
０を開く開弁状態とを形成するようになっている。The intake control valve 13 has a valve shaft 13
A is connected to the intake control valve actuator 14 via a link or the like (not shown), and the intake control valve actuator 14 is rotatably driven by a control signal from a control unit 19 which will be described later to stand up and the intake passage 10 is connected. Closed and the intake passage 1
A valve open state in which 0 is opened is formed.
【００１０】また、図中に示す１５は燃焼室５内に臨ん
でシリンダヘッド４に取り付けられた点火栓、１６は機
関回転数、クランク角を検出するクランク角センサ、１
７は吸気集合通路の上流側で吸入空気量を検出するエア
フローメータ、１８は吸入空気量を調整する図外のスロ
ットル弁のスロットル開度を検出するスロットルセンサ
をそれぞれ示し、これら点火栓１５及び各センサ１６〜
１８は、それぞれコントロールユニット１９に接続され
ている。Reference numeral 15 shown in the drawing is an ignition plug attached to the cylinder head 4 so as to face the inside of the combustion chamber 5, 16 is a crank angle sensor for detecting engine speed and crank angle, and 1 is a crank angle sensor.
Reference numeral 7 denotes an air flow meter for detecting the intake air amount on the upstream side of the intake collecting passage, and 18 denotes a throttle sensor for detecting the throttle opening of a throttle valve (not shown) for adjusting the intake air amount. Sensor 16-
Each 18 is connected to a control unit 19.
【００１１】機関を電気的に集中制御するコントロール
ユニット１９は、ＣＰＵ等からなる演算回路、ＲＯＭ，
ＲＡＭ等からなる記憶回路、入出力回路等を備えたマイ
クロコンピュータシステムとして構成され、その記憶回
路内には、図１２に示す制御マップが記憶されている。
即ち、この制御マップは、吸気制御弁１３の開閉動作を
制御するためのもので、希薄燃焼運転領域（図中「リー
ン」と示す）とストイキ運転領域（図中「ストイキ」と
示す）とが機関回転数Ｎと機関負荷ＴPとに対応して格
納されている。The control unit 19 for centrally electrically controlling the engine includes an arithmetic circuit including a CPU, a ROM,
It is configured as a microcomputer system including a storage circuit including a RAM and the like, an input / output circuit, and the like, and the control map shown in FIG. 12 is stored in the storage circuit.
That is, this control map is for controlling the opening / closing operation of the intake control valve 13, and the lean combustion operating region (indicated by "Lean" in the figure) and the stoichiometric operating region (indicated by "Stoichi" in the figure) are set. It is stored corresponding to the engine speed N and the engine load T P.
【００１２】そして、コントロールユニット１９は、制
御マップに基づいて、所定回転以下、所定負荷以下の希
薄燃焼運転領域では、吸気制御弁１３を閉弁させて吸入
空気の大部分を切欠部１３Ｃを介して通過させることに
より、燃焼室５内に適度なスワール，タンブルを生成し
て燃焼状態を安定化させる一方、理論空燃比近傍を目標
空燃比として運転するストイキ運転領域では、吸気制御
弁１３を開弁させて、吸入空気をそのまま燃焼室５内に
流入させるものである。Then, based on the control map, the control unit 19 closes the intake control valve 13 in the lean combustion operation region of a predetermined rotation or less and a predetermined load or less so that most of the intake air passes through the notch 13C. In order to generate a proper swirl and tumble in the combustion chamber 5 to stabilize the combustion state, the intake control valve 13 is opened in the stoichiometric operation region where the target air-fuel ratio is set near the stoichiometric air-fuel ratio. The valve is operated to allow the intake air to flow into the combustion chamber 5 as it is.
【００１３】従来技術による内燃機関の吸気装置は、上
述の如き構成を有するもので、希薄燃焼運転領域に達し
て、コントロールユニット１９が吸気制御弁アクチュエ
ータ１４を介して吸気制御弁１３を閉弁させると、吸入
空気の大部分が吸気制御弁１３の切欠部１３Ｃを介して
第１のポート部６Ａに流れるため、これにより、燃焼室
５内にスワール，タンブルが生成し、燃焼状態が安定化
する。The intake system for an internal combustion engine according to the prior art has the above-mentioned structure. When the lean combustion operation region is reached, the control unit 19 closes the intake control valve 13 via the intake control valve actuator 14. Then, most of the intake air flows to the first port portion 6A through the cutout portion 13C of the intake control valve 13, so that swirls and tumbles are generated in the combustion chamber 5 and the combustion state is stabilized. .
【００１４】[0014]
【発明が解決しようとする課題】ところで、上述した従
来技術による内燃機関の吸気装置では、所定の運転条件
下で吸気制御弁１３を閉弁させることにより、希薄燃焼
運転での燃焼状態の安定化を図っているが、吸気ポート
６は、鋳造によってシリンダヘッド４内に形成されるた
め、製造時の誤差によって吸気ポート６と吸気通路１０
との接続位置関係がずれてしまい、これにより、スワー
ル比、タンブル比が低下して、希薄燃焼運転時の運転性
等が悪化する可能性がある。In the intake system for an internal combustion engine according to the above-mentioned conventional technique, the intake control valve 13 is closed under a predetermined operating condition to stabilize the combustion state in the lean burn operation. However, since the intake port 6 is formed in the cylinder head 4 by casting, the intake port 6 and the intake passage 10 may be different due to a manufacturing error.
There is a possibility that the connection positional relationship with and shifts, which reduces the swirl ratio and the tumble ratio, and deteriorates the drivability during lean burn operation.
【００１５】即ち、吸気ポート６は、その形状の複雑さ
等に鑑みて、鋳造により成型されるのに対し、吸気通路
１０は、その内部に吸気制御弁１３を取り付ける関係
上、機械加工によって成型される。そして、鋳造の場合
は、機械加工に比べて製造誤差が大きいため、シリンダ
ヘッド４内における吸気ポート６の形成位置、特に、吸
気ポート６の上流側開口部６Ｃの形成位置が所定の基準
位置に対してばらつき易く、吸気ポート６の上流側開口
部６Ｃと吸気通路１０の接続口１０Ａとを正確に接続し
たつもりでも、実際には、上流側開口部６Ｃと接続口１
０Ａとがずれている場合がある。That is, the intake port 6 is molded by casting in consideration of the complexity of its shape, whereas the intake passage 10 is molded by machining because the intake control valve 13 is attached to the inside thereof. To be done. In the case of casting, since the manufacturing error is larger than that in machining, the formation position of the intake port 6 in the cylinder head 4, particularly the formation position of the upstream side opening 6C of the intake port 6 becomes a predetermined reference position. However, even if it is intended that the upstream opening 6C of the intake port 6 and the connection port 10A of the intake passage 10 are accurately connected, in reality, the upstream opening 6C and the connection port 1
There is a case where it is deviated from 0A.
【００１６】従って、上流側開口部６Ｃと接続口１０Ａ
とが基準位置で正確に接続されている場合には、希薄燃
焼運転に最適なスワール比，タンブル比を得ることがで
きるが、上流側開口部６Ｃと接続口１０Ａとの接続位置
関係がずれた場合には、そのずれの方向と大きさとによ
っては、スワール比、特にタンブル比が大きく減少する
ため、希薄燃焼運転性能が低下して、運転性等が悪化す
るおそれがある上に、機関毎に希薄燃焼運転性能がばら
つく可能性がある。特に、吸気制御弁の切欠部は、第１
のポート部に対応して弁体に横方向に形成されるため、
吸気ポートの形成位置が横方向にずれると、吸入空気流
に与える影響が大きい。Therefore, the upstream side opening 6C and the connection port 10A
When and are accurately connected at the reference position, the optimum swirl ratio and tumble ratio for the lean burn operation can be obtained, but the connection positional relationship between the upstream side opening 6C and the connection port 10A is deviated. In this case, depending on the direction and size of the deviation, the swirl ratio, particularly the tumble ratio, is greatly reduced, so the lean burn operation performance may be deteriorated, and the drivability may be deteriorated. Lean combustion operation performance may vary. In particular, the cutout portion of the intake control valve is
Since it is formed laterally on the valve body corresponding to the port part of
If the formation position of the intake port shifts in the lateral direction, it greatly affects the intake air flow.
【００１７】また、かかる寸法公差に起因する上流側開
口部６Ｃと接続口１０Ａとの接続位置関係のずれを解消
すべく、鋳造の精度管理を高めることも考えられるが、
上流側開口部６Ｃの形成位置ずれは、鋳造という製造プ
ロセスによって定まり、本質的に機械加工との間に精度
差が存在するため、位置ずれを完全に解消するのは困難
である上に、製造コスト等が大幅に増大する。Further, in order to eliminate the deviation of the connection positional relationship between the upstream side opening 6C and the connection port 10A due to the dimensional tolerance, it is conceivable to improve the precision control of casting.
The positional deviation of the upstream opening 6C is determined by a manufacturing process called casting, and since there is a difference in accuracy between the upstream and the opening, it is difficult to completely eliminate the positional deviation. The cost etc. will increase significantly.
【００１８】そこで、本発明は、かかる従来技術の問題
に鑑みてなされたもので、その目的は、吸気ポートと吸
気通路との接続位置関係がずれた場合でも、適度なスワ
ール，タンブルを確保することにより、希薄燃焼運転時
の運転性等を向上できるようにした内燃機関の吸気装置
の提供にある。Therefore, the present invention has been made in view of the above problems of the prior art, and an object thereof is to ensure proper swirl and tumble even when the connection positional relationship between the intake port and the intake passage is deviated. Accordingly, it is an object of the present invention to provide an intake system for an internal combustion engine that can improve the drivability during lean burn operation.
【００１９】[0019]
【課題を解決するための手段】そこで、本発明に係る内
燃機関の吸気装置が採用する構成は、シリンダを施蓋す
るシリンダヘッドに設けられ、下流側が二股に分岐して
一対のポート部となった吸気ポートと、この吸気ポート
の上流側開口部に接続された吸気通路と、この吸気通路
内に回動可能に設けられ、前記一対のポート部のうち第
１のポート部に対応する切欠部が弁体の横方向に形成さ
れた吸気制御弁とを有する内燃機関の吸気装置であっ
て、前記吸気通路と前記吸気ポートとを基準位置関係で
接続したときに、前記吸気通路の接続口の横方向両側部
のうち前記吸気制御弁の切欠部側に位置する第１の側部
が前記吸気ポートの上流側開口部よりも所定寸法だけ横
方向外側に位置するように設定したことを特徴としてい
る。Therefore, the structure adopted by the intake system for an internal combustion engine according to the present invention is provided in a cylinder head for covering a cylinder, and the downstream side is bifurcated into a pair of port portions. An intake port, an intake passage connected to an upstream opening of the intake port, and a cutout portion rotatably provided in the intake passage and corresponding to a first port portion of the pair of port portions. Is an intake device for an internal combustion engine having an intake control valve formed in the lateral direction of the valve body, and when the intake passage and the intake port are connected in a reference positional relationship, It is characterized in that the first side portion, which is located on the notch side of the intake control valve, of both side portions in the lateral direction is set to be laterally outward by a predetermined dimension from the upstream side opening portion of the intake port. There is.
【００２０】また、より具体的には、シリンダを施蓋す
るシリンダヘッドに鋳造成型によって設けられ、下流側
が二股に分岐して一対のポート部となった吸気ポート
と、この吸気ポートの上流側開口部に接続口を介して接
続され、少なくとも該接続口が機械加工によって成形さ
れた吸気通路と、この吸気通路内に前記接続口の近傍に
位置して回動可能に設けられ、前記一対のポート部のう
ち第１のポート部に対応する切欠部が弁体の横方向に形
成された吸気制御弁とを有する内燃機関の吸気装置であ
って、前記吸気通路の接続口の横幅を前記吸気ポートの
上流側開口部の横幅よりも所定寸法だけ大きく形成する
と共に、前記吸気制御弁の切欠部を前記吸気ポートの中
心線から前記所定寸法だけ偏心させて弁体の横方向に形
成し、前記吸気通路と前記吸気ポートとを基準位置関係
で接続したときに、前記吸気通路の接続口の横方向両側
部のうち前記吸気制御弁の切欠部側に位置する第１の側
部が前記吸気ポートの上流側開口部よりも前記所定寸法
だけ横方向外側に位置するように設定し、かつ、前記所
定寸法は、前記吸気ポートの製造公差の最大値に設定し
たことを特徴としている。More specifically, an intake port which is provided on the cylinder head for covering the cylinder by casting, and which has a bifurcated downstream side to form a pair of port portions, and an upstream opening of the intake port. And an intake passage formed by machining at least the connection opening, and rotatably provided in the intake passage in the vicinity of the connection opening. An intake device for an internal combustion engine, wherein a notch corresponding to a first port of the intake port is formed in a lateral direction of a valve body, and a lateral width of a connection port of the intake passage is set to the intake port. Is formed to be larger than the lateral width of the upstream side opening of the intake control valve by a predetermined dimension, and the notch of the intake control valve is formed in the lateral direction of the valve body by decentering from the center line of the intake port by the predetermined dimension. aisle When the intake port is connected in the reference positional relationship, the first side part located on the notch side of the intake control valve among the laterally opposite side parts of the connection port of the intake passage is the upstream side of the intake port. It is characterized in that it is set so as to be located laterally outward by the predetermined dimension with respect to the opening, and the predetermined dimension is set to the maximum value of the manufacturing tolerance of the intake port.
【００２１】さらに、前記吸気通路と前記吸気ポートと
を基準位置関係で接続したときに、前記第１の側部と前
記吸気ポートの上流側開口部との間に形成される段部に
面取り部を設けるのが好ましい。Further, when the intake passage and the intake port are connected in a reference positional relationship, a chamfered portion is formed on a step portion formed between the first side portion and the upstream opening of the intake port. Is preferably provided.
【００２２】[0022]
【作用】通常、シリンダヘッド内における吸気ポートの
形成位置が所定の基準位置にあるときに、希薄燃焼運転
に最適なスワール，タンブルを得るべく、吸気ポート、
吸気通路、吸気制御弁の相互関係が設定されるが、製造
公差によって吸気ポートの形成位置が所定の基準位置か
ら切欠部の形成方向である横方向にずれると、この「ず
れ」によって、吸気制御弁の上流側開口部と吸気ポート
の第１のポート部との位置関係もずれるため、スワール
比，タンブル比が低下する。特に、吸気ポートの形成位
置が横方向にずれると、吸気ポートの上流側開口部と吸
気通路の接続口との間に段部が形成され、この段部によ
って吸入空気流の流速が変化するため、タンブル比が影
響を受け易い。In general, when the formation position of the intake port in the cylinder head is at a predetermined reference position, in order to obtain swirls and tumbles optimal for lean burn operation, the intake port,
The mutual relationship between the intake passage and the intake control valve is set, but if the formation position of the intake port deviates from the predetermined reference position in the lateral direction, which is the direction of the notch, due to manufacturing tolerances, this "deviation" causes intake control. Since the positional relationship between the upstream opening of the valve and the first port of the intake port also shifts, the swirl ratio and tumble ratio decrease. In particular, if the formation position of the intake port shifts laterally, a step is formed between the upstream opening of the intake port and the connection port of the intake passage, and the step changes the flow velocity of the intake air flow. The tumble ratio is easily affected.
【００２３】しかし、本発明では、吸気通路と吸気ポー
トとを基準位置関係で接続したときに、吸気通路の接続
口の横方向両側部のうち吸気制御弁の切欠部側に位置す
る第１の側部が吸気ポートの上流側開口部よりも所定寸
法だけ横方向外側に位置するように設定する構成とした
ため、吸気ポートの形成位置が基準位置から吸気制御弁
の切欠部側に向けて横方向にずれた場合には、接続口の
第１の側部と上流側開口部とが近接し、両者間の段部が
減少するため、スワール比，タンブル比の低下が少なく
なる。However, according to the present invention, when the intake passage and the intake port are connected in the reference positional relationship, the first side of the intake control valve is located on the side of the cutout portion of the intake control valve in both lateral portions of the connection port of the intake passage. Since the side part is set to be located laterally outward from the upstream opening of the intake port by a predetermined dimension, the intake port formation position is lateral from the reference position toward the cutout side of the intake control valve. In the case of the deviation, the first side portion of the connection port and the upstream side opening portion come close to each other, and the step portion between the both is reduced, so that the swirl ratio and the tumble ratio are less likely to decrease.
【００２４】これとは逆に、吸気ポートの形成位置が基
準位置から吸気制御弁の切欠部の反対側に向けてずれた
場合には、上流側開口部と接続口との間の切欠部側に、
吸入空気の流路を狭めるような段部が前記所定寸法以上
にわたって形成されるが、この段部によって吸入空気の
流速が増大し、流速の減衰域が下流側にシフトするた
め、タンブル比の低下率は小さくなる。On the contrary, when the formation position of the intake port deviates from the reference position toward the opposite side of the notch of the intake control valve, the notch side between the upstream opening and the connection port. To
A step portion that narrows the flow path of the intake air is formed over the predetermined size or more, but this step portion increases the flow velocity of the intake air and shifts the attenuation region of the flow velocity to the downstream side, thus lowering the tumble ratio. The rate becomes smaller.
【００２５】従って、吸気ポートの形成位置が横方向の
左右いずれかの方向にずれても、その位置ずれ量が所定
寸法以下であれば、スワール比，タンブル比の低下を最
小限に抑えることができる。Therefore, even if the formation position of the intake port deviates to the left or right in the lateral direction, if the positional deviation amount is equal to or smaller than the predetermined dimension, the reduction of the swirl ratio and the tumble ratio can be minimized. it can.
【００２６】また、より具体的な請求項２の構成によれ
ば、吸気通路の接続口の横幅を吸気ポートの上流側開口
部の横幅よりも所定寸法だけ大きく形成するため、位置
ずれによるスワール比，タンブル比の低下を抑制するの
に必要最低限の大きさで吸気通路を形成することができ
る。さらに、吸気制御弁の切欠部を吸気ポートの中心線
から前記所定寸法だけ偏心させて弁体の横方向に形成す
るため、吸気ポートの形成位置が切欠部側に所定寸法ず
れた場合に、切欠部の位置と吸気ポートの中心線とが一
致する。また、請求項２の構成では、前記所定寸法を吸
気ポートの製造公差の最大値に設定するため、吸気ポー
トの形成位置ずれに拘わらず、常に、スワール比，タン
ブル比を確保して希薄燃焼運転時の運転性を維持でき
る。Further, according to the more specific configuration of claim 2, since the lateral width of the connection port of the intake passage is formed to be larger than the lateral width of the upstream side opening of the intake port by a predetermined dimension, the swirl ratio due to the positional deviation is formed. The intake passage can be formed with the minimum size necessary to suppress the decrease in the tumble ratio. Further, since the notch of the intake control valve is formed eccentrically from the center line of the intake port by the predetermined dimension in the lateral direction of the valve body, when the formation position of the intake port is shifted to the notch by the predetermined dimension, the notch is formed. The position of the part coincides with the center line of the intake port. Further, in the configuration of claim 2, since the predetermined size is set to the maximum value of the manufacturing tolerance of the intake port, the swirl ratio and the tumble ratio are always secured regardless of the displacement of the formation position of the intake port, and the lean burn operation is performed. The drivability of time can be maintained.
【００２７】さらに、接続口の第１の側部と吸気ポート
の上流側開口部との間に形成される段部に面取り部を設
ければ、吸気ポートと吸気通路とが位置ずれなく基準位
置関係で接続された場合に、切欠部を通過した吸入空気
を滑らかに第１のポート部に誘導することができる。Further, if the chamfered portion is provided on the step portion formed between the first side portion of the connection port and the upstream side opening portion of the intake port, the intake port and the intake passage can be positioned at the reference position without displacement. When connected in a relationship, the intake air that has passed through the notch can be smoothly guided to the first port.
【００２８】[0028]
【実施例】以下、本発明の実施例を図１〜図９を参照し
つつ説明する。なお、以下の各実施例では、上述した従
来技術と同一の構成に同一の符号を付し、その説明を省
略するものとする。Embodiments of the present invention will be described below with reference to FIGS. In each of the following embodiments, the same components as those of the above-described conventional technique are designated by the same reference numerals, and the description thereof will be omitted.
【００２９】本実施例による吸気通路２１は、従来技術
で述べた吸気通路１０と同様に、図外のコレクタ部及び
吸気集合通路と共に吸気マニホールド１１を構成してお
り、その下流側に位置する接続口２１Ａが吸気ポート６
の上流側開口部６Ｃに接続されているものの、接続口２
１Ａの横方向両側部２１Ａ1，２１Ａ2のうち、後述する
吸気制御弁２２の切欠部２２Ｃ側に位置する第１の側部
２１Ａ1は、図１に示す所定の基準位置関係において、
吸気ポート６の上流側開口部６Ｃよりも所定寸法δだけ
横方向外側に位置している。Like the intake passage 10 described in the prior art, the intake passage 21 according to the present embodiment constitutes an intake manifold 11 together with a collector portion and an intake collecting passage (not shown), and is connected downstream thereof. Port 21A is intake port 6
Connected to the upstream opening 6C of the
Of the lateral side portions 21A 1 and 21A 2 of 1A, the first side portion 21A 1 located on the side of the cutout portion 22C of the intake control valve 22, which will be described later, has a predetermined reference positional relationship shown in FIG.
It is located laterally outside by a predetermined dimension δ from the upstream opening 6C of the intake port 6.
【００３０】より具体的に説明すると、本実施例による
吸気通路２１は、図２の説明図にも示す如く、その横幅
寸法Ｗ1が吸気ポート６の上流側開口部６Ｃの横幅寸法
Ｗよりも、所定寸法δだけ大きくなるように拡幅して形
成されている。ここで、所定寸法δは、吸気ポート６の
形成位置が製造公差によってずれる可能性がある最大の
値として設定されるもので、例えば実験等によって各機
関の種類毎に予め求められ、一例として２ｍｍ程度に設
定されている。More specifically, the intake passage 21 according to the present embodiment has a lateral width W 1 which is larger than a lateral width W of the upstream opening 6C of the intake port 6, as shown in the explanatory view of FIG. The width is formed so as to increase by a predetermined dimension δ. Here, the predetermined dimension δ is set as a maximum value at which the formation position of the intake port 6 may be displaced due to manufacturing tolerances, and is obtained in advance for each engine type by, for example, an experiment, and is 2 mm as an example. It is set to a degree.
【００３１】また、切欠部２２Ｃ側に位置する第１の側
部２１Ａ1と切欠部２２Ｃの反対側に位置する第２の側
部２１Ａ2とは、ともに吸気ポート６の上流側開口部６
Ｃの両側部の形状と沿うように形成され、これら各側部
２１Ａ1，２１Ａ2間の端部をつなぐ上下の辺も上流側開
口部６Ｃの上下の辺とそれぞれ一致しており、全体とし
て、接続口２１Ａの断面形状は、上流側開口部６Ｃの断
面形状を横方向に所定寸法δだけ引き伸ばした略楕円状
ないし略小判状となっている。なお、図２中の軸線Ｏ−
Ｏは、上流側開口部６Ｃの横方向の中心（中心線Ｐ）に
垂直方向で直交する線である。The first side portion 21A 1 located on the cutout portion 22C side and the second side portion 21A 2 located on the opposite side of the cutout portion 22C are both located at the upstream opening 6 of the intake port 6.
The upper and lower sides which are formed so as to follow the shape of both side portions of C and which connect the end portions between these respective side portions 21A 1 and 21A 2 also coincide with the upper and lower sides of the upstream opening 6C, respectively, and as a whole. The cross-sectional shape of the connection port 21A is a substantially elliptical or oval shape in which the cross-sectional shape of the upstream opening 6C is laterally stretched by a predetermined dimension δ. The axis O- in FIG.
O is a line perpendicular to the horizontal center (center line P) of the upstream opening 6C.
【００３２】ここで、本実施例では、あたかも、吸気通
路２１の全体（接続口２１Ａからコレクタ部の接続口ま
での間）を、上流側開口部６Ｃよりも所定寸法δだけ拡
幅して形成する如く例示しているが、本発明は吸気ポー
ト６の位置ずれを吸収して適切なスワール比，タンブル
比を生成することを目的とするため、吸気通路２１の全
体が一様に拡幅して形成される必要は必ずしもなく、例
えば接続口２１Ａの近傍、好ましくは、接続口２１Ａの
開口端面から吸気制御弁２２の上流側近傍までの範囲
で、吸気ポート６の上流側開口部６Ｃよりも所定寸法δ
だけ拡幅して形成されていればよく、これより上流側の
形状は特に問わない。Here, in the present embodiment, it is as if the entire intake passage 21 (between the connection port 21A and the connection port of the collector portion) is wider than the upstream opening 6C by a predetermined dimension δ. However, since the present invention aims to absorb the positional deviation of the intake port 6 and generate an appropriate swirl ratio and tumble ratio, the entire intake passage 21 is formed to have a uniform width. For example, in the vicinity of the connection port 21A, preferably in the range from the opening end face of the connection port 21A to the vicinity of the upstream side of the intake control valve 22, a predetermined dimension larger than the upstream opening 6C of the intake port 6 is provided. δ
It suffices that it is formed by widening only the width, and the shape on the upstream side of this is not particularly limited.
【００３３】また、本明細書にいう「基準位置関係」と
は、図１に示す如く、吸気ポート６が所定の基準位置に
形成されたときの接続状態をいい、具体的には、吸気ポ
ート６の中心線Ｐに対して吸気通路２１の中心線Ｐ1が
吸気制御弁２２の切欠部２２Ｃ側に所定寸法δだけ偏心
し、この結果、接続口２１Ａの第１の側部２１Ａ1が所
定寸法δだけ上流側開口部６Ｃの横方向外側に位置する
状態をいう。The "reference position relationship" referred to in the present specification means a connection state when the intake port 6 is formed at a predetermined reference position as shown in FIG. The center line P 1 of the intake passage 21 is eccentric to the notch 22C side of the intake control valve 22 with respect to the center line P of 6 by a predetermined dimension δ, and as a result, the first side portion 21A 1 of the connection port 21A is predetermined. A state in which the dimension δ is located laterally outside the upstream opening 6C.
【００３４】なお、本実施例では、吸気通路２１の横幅
Ｗ1を所定寸法δだけ拡幅するため、この基準位置関係
においては、この拡幅分δが全て第１の側部２１Ａ1側
に後述の段部２３として現れ、これにより接続口２１Ａ
の第２の側部２１Ａ2が上流側開口部６Ｃに一致する。
但し、特に図示はしないが、本発明はこれに限らず、吸
気通路２１の横幅Ｗ2を所定寸法δよりも長い寸法δ1で
拡幅してもよく（Ｗ2＝Ｗ＋δ1、δ1＞δ、Ｗ2＞
Ｗ1）、この場合には、中心線Ｐ，Ｐ1間の偏心量が所定
寸法δとなる基準位置関係で接続すると、これら各寸法
δ，δ1の差分Δδだけ、第２の側部２１Ａ2が上流側開
口部６Ｃの横方向外側に位置することになるため（Δδ
＝δ1−δ）、この結果、第２の側部２１Ａ2側にも他の
段部が形成される。In this embodiment, since the lateral width W 1 of the intake passage 21 is widened by the predetermined dimension δ, in this reference positional relationship, the widened portion δ is entirely on the first side portion 21A 1 side, which will be described later. Appears as a step portion 23, whereby the connection port 21A
The second side portion 21A 2 of is aligned with the upstream side opening portion 6C.
However, although not particularly shown, the present invention is not limited to this, and the lateral width W 2 of the intake passage 21 may be widened by a dimension δ 1 longer than the predetermined dimension δ (W 2 = W + δ 1 , δ 1 > δ). , W 2 ＞
W 1 ), in this case, if the center lines P and P 1 are connected in a reference positional relationship in which the eccentric amount is a predetermined dimension δ, the difference Δδ between these dimensions δ and δ 1 is equal to the second side portion 21A. 2 is located laterally outside the upstream opening 6C (Δδ
= Δ 1 −δ), and as a result, another step is also formed on the second side 21A 2 side.
【００３５】しかし、このように、吸気通路２１の横幅
をＷ2に拡げて、第２の側部２１Ａ2側に段部を形成して
も、この第２の側部２１Ａ2付近は、吸気制御弁２２の
閉弁時に吸入空気の流れが遮断される箇所であり、スワ
ール，タンブルの生成に与える影響がもともと小さいた
め、製造コスト、取付寸法等が増大する割には、得られ
る効果が少ない。従って、換言すれば、本実施例では、
吸気通路２１の横幅を必要最低限の所定寸法δだけ拡幅
することにより、製造コストや取付寸法の増大を抑制し
つつ所望の効果を得ているのである。[0035] However, in this way, by expanding the width of the intake passage 21 to W 2, be formed a step portion on the second side 21A 2 side, the second side 21A near 2, intake This is a part where the flow of intake air is shut off when the control valve 22 is closed, and the effect on swirl and tumble generation is originally small, so the effect obtained is small despite the increase in manufacturing cost, mounting dimensions, etc. . Therefore, in other words, in this embodiment,
By widening the lateral width of the intake passage 21 by the required minimum predetermined size δ, the desired effect can be obtained while suppressing an increase in manufacturing cost and mounting size.
【００３６】本実施例による吸気制御弁２２は、従来技
術の吸気制御弁１３と同様に、吸気通路２１の接続口２
１Ａの上流側近傍に設けられ、吸気制御弁アクチュエー
タ１４に接続された弁軸２２Ａと、この弁軸２２Ａに取
り付けられた略楕円板状の弁体２２Ｂと、この弁体２２
Ｂの上側半分のうち第１のポート部６Ａに対応する箇所
を部分的に横方向に切り欠いてなる切欠部２２Ｃとから
バタフライ弁として大略構成され、切欠部２２Ｃは、弁
軸２２Ａの上側を寸法ｈ1だけオフセットして横方向に
切り欠いた水平部２２Ｃ1と、弁体２２Ｂの横幅方向の
略中心を通って水平部２２Ｃ1と直交する垂直部２２Ｃ2
とを有している（従って、この垂直部２２Ｃ2は、吸気
ポート６の中心線Ｐから所定寸法δだけ偏心してい
る）。また、本実施例では、吸気通路２１の横幅Ｗ1を
吸気ポート６の上流側開口部６Ｃの横幅Ｗよりも所定寸
法δだけ拡げているため、これに応じて、吸気制御弁２
２の横幅も従来技術で述べた吸気制御弁１３の横幅より
も長くなっている。The intake control valve 22 according to the present embodiment is similar to the intake control valve 13 of the prior art in that the connection port 2 of the intake passage 21.
1A, a valve shaft 22A connected to the intake control valve actuator 14 near the upstream side, a valve body 22B having a substantially elliptical plate shape attached to the valve shaft 22A, and the valve body 22.
Of the upper half of B, the portion corresponding to the first port portion 6A is roughly configured as a butterfly valve by a cutout portion 22C that is partially cut out in the lateral direction, and the cutout portion 22C is located above the valve shaft 22A. A horizontal portion 22C 1 that is offset by a dimension h 1 and is cut out in the lateral direction, and a vertical portion 22C 2 that is orthogonal to the horizontal portion 22C 1 and passes through the substantial center of the valve body 22B in the lateral width direction.
(Therefore, the vertical portion 22C 2 is eccentric from the center line P of the intake port 6 by a predetermined dimension δ). Further, in this embodiment, the lateral width W 1 of the intake passage 21 is wider than the lateral width W of the upstream opening 6C of the intake port 6 by the predetermined dimension δ, and accordingly, the intake control valve 2
The width of 2 is also larger than the width of the intake control valve 13 described in the prior art.
【００３７】そして、上述の如く、基準位置関係で接続
したときに、接続口２１Ａの第１の側部２１Ａ1が所定
寸法δだけ上流側開口部６Ｃの横方向外側に位置するた
め、この第１の側部２１Ａ1と上流側開口部６Ｃの側部
との間には、所定寸法δの段部２３が形成され、この段
部２３によって切欠部２２Ｃの下流側の流路が局所的に
狭められる。換言すれば、基準位置関係において、第１
の側部２１Ａ1の内側に、上流側開口部６Ｃの側部が所
定寸法δだけ入り込むことにより、段部２３が形成され
ていると把握できる。Then, as described above, when the connection is made in the reference positional relationship, the first side portion 21A 1 of the connection port 21A is located laterally outside the upstream opening 6C by a predetermined dimension δ. A step portion 23 having a predetermined size δ is formed between the side portion 21A 1 of 1 and the side portion of the upstream side opening portion 6C, and the step portion 23 locally forms a flow path on the downstream side of the cutout portion 22C. Narrowed. In other words, in the reference positional relationship, the first
It can be understood that the step portion 23 is formed by inserting the side portion of the upstream side opening portion 6C by a predetermined dimension δ inside the side portion 21A 1 .
【００３８】次に、本実施例の作用について述べる前
に、まず、吸気ポート６の形成位置の横ずれがスワール
比，タンブル比に与える影響について、図３，図４を参
照しつつ説明する。Before describing the operation of this embodiment, first, the influence of the lateral deviation of the formation position of the intake port 6 on the swirl ratio and the tumble ratio will be described with reference to FIGS. 3 and 4.
【００３９】即ち、図３は、従来技術による内燃機関の
吸気装置において、吸気ポート６の形成位置が横方向に
ずれる態様を示した説明図であって、図３中の（Ａ）
は、吸気ポート６が吸気制御弁１３の切欠部１３Ｃの反
対側に所定寸法δだけ横ずれして吸入空気の流路が縮小
した場合（以下、「縮小側ずれ状態」という）、図３中
の（Ｂ）は、吸気ポート６に形成位置のずれがなく、吸
気ポート６と吸気通路１０とが基準位置関係にある場合
（以下、「基準状態」という）、図３中の（Ｃ）は、吸
気ポート６が切欠部１３Ｃ側に所定寸法δだけ横ずれし
て吸入空気の流路が拡大した場合（以下、「拡大側ずれ
状態」という）をそれぞれ示す。That is, FIG. 3 is an explanatory view showing a mode in which the formation position of the intake port 6 is laterally displaced in the intake device for an internal combustion engine according to the prior art.
3 indicates that when the intake port 6 laterally shifts to the side opposite to the cutout portion 13C of the intake control valve 13 by a predetermined dimension δ and the flow path of the intake air is reduced (hereinafter, referred to as “reduction side shift state”). 3B shows a case where the intake port 6 has no deviation in the formation position and the intake port 6 and the intake passage 10 have a reference positional relationship (hereinafter, referred to as “reference state”), (C) in FIG. The case where the intake port 6 is laterally displaced toward the notch 13C by a predetermined dimension δ and the flow path of the intake air is expanded (hereinafter, referred to as “expansion side deviation state”) is shown.
【００４０】基準状態（Ｂ）では、切欠部１３Ｃの垂直
部１３Ｃ2が吸気ポート６の分岐点６Ｄと略一致し、吸
気ポート６の上流側開口部６Ｃの側部と切欠部１３Ｃの
垂直部１３Ｃ2との間の相対距離（以下、「相対距離」
という）Ｌは、切欠部１３Ｃの水平部１３Ｃ1の寸法と
略一致する。In the standard state (B), the vertical portion 13C 2 of the cutout portion 13C substantially coincides with the branch point 6D of the intake port 6, and the side portion of the upstream opening 6C of the intake port 6 and the vertical portion of the cutout portion 13C. 13C 2 relative distance (hereinafter, “relative distance”
L) is substantially the same as the dimension of the horizontal portion 13C 1 of the cutout portion 13C.
【００４１】また、縮小側ずれ状態（Ａ）では、切欠部
１３の垂直部１３Ｃ2が各ポート部６Ａ，６Ｂの分岐点
６Ｄから所定寸法δだけ相対的に第１のポート部６Ａ側
にずれ込むと共に、上流側開口部６Ｃの側部が切欠部１
３Ｃ側に入り込んで、所定寸法δの幅の段部Ｇ1が形成
され、この段部Ｇ1の分だけ、相対距離がＬ1と狭くなる
（Ｌ1＝Ｌ−δ）。Further, in the contraction side shift state (A), the vertical portion 13C 2 of the cutout portion 13 is relatively shifted from the branch point 6D of each port portion 6A, 6B by the predetermined dimension δ toward the first port portion 6A side. At the same time, the side portion of the upstream opening 6C is the cutout portion 1.
The step portion G 1 having a width of a predetermined dimension δ is formed by entering the 3C side, and the relative distance is reduced to L 1 by the step portion G 1 (L 1 = L−δ).
【００４２】これとは逆に、拡大側ずれ状態（Ｃ）で
は、切欠部１３Ｃの垂直部１３Ｃ2が分岐点６Ｄから所
定寸法δだけ相対的に第２のポート部６Ｂ側にずれ込ん
で、上流側開口部６Ｃの側部が切欠部１３Ｃの横方向外
側に位置し、これにより所定寸法δの幅の段部Ｇ2が形
成されて、相対距離がＬ2に広がる（Ｌ2＝Ｌ＋δ）。Contrary to this, in the expanded side shift state (C), the vertical portion 13C 2 of the cutout 13C relatively shifts from the branch point 6D by the predetermined dimension δ to the second port portion 6B side, and the upstream side. side of the side opening 6C is positioned laterally outwardly of the cutout portion 13C, thereby step portion G 2 of the width of a predetermined size [delta] is formed, the relative distance spreads L 2 (L 2 = L + δ).
【００４３】次に、これらの各接続状態（Ａ）〜（Ｃ）
とスワール比，タンブル比との関係について、図４の特
性図を参照しつつ説明する。Next, each of these connection states (A) to (C)
The relationship between the swirl ratio and the tumble ratio will be described with reference to the characteristic diagram of FIG.
【００４４】ここで、図４中、縮小側ずれ状態（Ａ）を
記号◇で、基準状態（Ｂ）を記号☆で、拡大側ずれ状態
（Ｃ）を記号◆で、それぞれ示す。In FIG. 4, the contraction side deviation state (A) is indicated by the symbol ⋄, the reference state (B) is indicated by the symbol ☆, and the enlargement side deviation state (C) is indicated by the symbol ◆.
【００４５】また、図４中に示す記号○は、吸気ポート
６の形成位置ずれがない状態で、切欠部１３Ｃの水平部
１３Ｃ1の長さを縮小側ずれ状態（Ａ）の相対距離Ｌ1に
設定した場合（基準状態（Ｂ）において切欠部１３Ｃの
幅を小さくした場合）を、同様に、記号●は、吸気ポー
ト６の形成位置ずれがない状態で、切欠部１３Ｃの水平
部１３Ｃ1の長さを拡大側ずれ状態（Ｃ）の相対距離Ｌ2
に設定した場合（基準状態（Ｂ）において切欠部１３Ｃ
の幅を広げた場合）を、それぞれ示し、これらは、吸気
制御弁１３の切欠部１３Ｃと吸気ポート６との相対関係
の変動がスワール比等に与える影響を知るために用意さ
れたものである。Further, the symbol ◯ shown in FIG. 4 indicates that the length of the horizontal portion 13C 1 of the cutout portion 13C is reduced when the intake port 6 is not displaced, and the relative distance L 1 in the reduced side displacement state (A). (When the width of the cutout 13C is reduced in the reference state (B)), the symbol ● similarly indicates that the horizontal portion 13C 1 of the cutout 13C is in the state where there is no displacement of the formation position of the intake port 6. The relative distance L 2 in the side offset state (C)
When set to (notch portion 13C in the reference state (B)
(When the width of the intake control valve 13 is widened), which are prepared in order to know the influence of the variation in the relative relationship between the cutout portion 13C of the intake control valve 13 and the intake port 6 on the swirl ratio and the like. .
【００４６】図４を参照すると、記号☆で示す通り、基
準状態（Ｂ）では、スワール比，タンブル比ともに略
「３」程度の値であるのに対し、縮小側ずれ状態（Ａ）
では、記号◇で示す通り、タンブル比が低下するもの
の、その低下分は比較的小さく、拡大側ずれ状態（Ｃ）
では、記号◆で示す通り、スワール比，タンブル比共に
大きく低下することが分かる。Referring to FIG. 4, as indicated by the symbol *, in the standard state (B), both the swirl ratio and the tumble ratio are about "3", while the reduction side shift state (A).
Then, as indicated by the symbol ◇, the tumble ratio decreases, but the decrease is relatively small, and the expansion side shift state (C)
Then, as indicated by the symbol ◆, it is found that both the swirl ratio and the tumble ratio are greatly reduced.
【００４７】また、吸気ポート６の形成位置ずれをなく
した状態で、相対距離だけを縮小側ずれ状態（Ａ）にお
ける相対距離Ｌ1に合わせた場合は、記号○で示す通
り、スワール比，タンブル比ともに殆ど変化がなく、同
様に、相対距離だけを拡大側ずれ状態（Ｃ）のＬ2に合
わせた場合は、記号●に示す如く、ややスワール比が低
下するものの、タンブル比に殆ど変化はないことが分か
る。If the relative distance alone is adjusted to the relative distance L 1 in the reduction side shift state (A) with the formation position shift of the intake port 6 eliminated, the swirl ratio and tumble are as shown by the symbol ◯. There is almost no change in the ratio, and similarly, when only the relative distance is adjusted to L 2 in the enlarged side shift state (C), the swirl ratio slightly decreases as shown by the symbol ●, but there is almost no change in the tumble ratio. I know there isn't.
【００４８】一方、図５は、相対距離とリーン限界（希
薄燃焼運転可能な空燃比の限界）との関係を示す特性図
であって、吸気ポート６の分岐点６Ｄと切欠部１３Ｃの
垂直部１３Ｃ2とが略同一線上に位置する基準状態
（Ｂ）では、記号☆で示す通り、リーン限界の空燃比は
略「２４．５」程度であるのに対し、相対距離Ｌ1が所
定寸法δだけ短くなる縮小側ずれ状態（Ａ）では、記号
◇で示す通り、殆ど変化せず、相対距離Ｌ2が所定寸法
δだけ長くなる拡大側ずれ状態（Ｃ）では、記号◆で示
す通り、リーン限界の空燃比が略「２２」程度まで大幅
に低下する。On the other hand, FIG. 5 is a characteristic diagram showing the relationship between the relative distance and the lean limit (the limit of the air-fuel ratio at which lean-burn operation is possible). The branch point 6D of the intake port 6 and the vertical portion of the notch 13C. In the standard state (B) in which 13C 2 is located on substantially the same line, the lean limit air-fuel ratio is about “24.5”, while the relative distance L 1 is the predetermined dimension δ, as indicated by the symbol ☆. In the contraction side shift state (A) where it shortens only, there is almost no change as indicated by the symbol ◇, and in the enlargement side shift state (C) where the relative distance L 2 becomes longer by the predetermined dimension δ, as indicated by the symbol ◆, lean The limit air-fuel ratio is significantly reduced to about "22".
【００４９】また、吸気ポート６の形成位置ずれをなく
した状態で、相対距離のみを縮小側ずれ状態（Ａ）の相
対距離Ｌ1に一致させた場合は、記号○に示す通り、リ
ーン限界の空燃比が略「２４」程度まで低下するが、そ
の変化は少なく、同様に、相対距離を拡大側ずれ状態
（Ｃ）の相対距離Ｌ2に一致させた場合も、記号●で示
す如く、リーン限界の空燃比は少しだけ低下する。Further, when only the relative distance is matched with the relative distance L 1 in the reduction side deviation state (A) in the state where the formation position deviation of the intake port 6 is eliminated, as shown by the symbol ◯, the lean limit is reached. Although the air-fuel ratio decreases to about "24", the change is small, and similarly, when the relative distance is made to coincide with the relative distance L 2 in the expanded side shift state (C), as indicated by the symbol ●, the lean air-fuel ratio is lean. The marginal air-fuel ratio is slightly reduced.
【００５０】従って、これら図４，図５から、上流側開
口部６Ｃの両側部のうち切欠部１３側に位置する側部と
切欠部１３Ｃの垂直部１３Ｃ2との間の相対距離がＬ2に
長くなると、記号◆，●に示す通り、スワール比，タン
ブル比が共に減少し、リーン限界の空燃比も低下するこ
とと、相対距離が同じでも段部Ｇ2が形成された拡大側
ずれ状態（Ｃ）の方がタンブル比の低下が著しいことと
が分かり、これによって、タンブル比の低下は、特に、
段部Ｇ2の影響によるものであることが理解できる。Therefore, from these FIGS. 4 and 5, the relative distance between the side portion located on the side of the cutout portion 13 and the vertical portion 13C 2 of the cutout portion 13C is L 2 on both sides of the upstream side opening portion 6C. becomes longer, the symbol ◆, as shown in ●, swirl ratio, decreased tumble ratio are both a possible to decrease the air-fuel ratio of the lean limit, enlarged side shift state relative distance is stepped portion G 2 is formed even with the same It can be seen that the tumble ratio is significantly reduced in (C).
It can be understood that this is due to the influence of the step G 2 .
【００５１】また、記号◇で示す通り、吸気ポート６の
形成位置が切欠部１３Ｃの反対側にずれても、スワール
比，タンブル比、リーン限界の空燃比ともに、その低下
が小さいため、吸入空気の流路を縮小する段部Ｇ1が形
成されても、この段部Ｇ1は、希薄燃焼運転に殆ど影響
を与えないことが理解できる。Further, as indicated by the symbol ◇, even if the formation position of the intake port 6 deviates to the side opposite to the cutout portion 13C, the reductions in the swirl ratio, the tumble ratio, and the lean limit air-fuel ratio are small, so the intake air is reduced. It can be understood that even if the step portion G 1 that reduces the flow path is formed, the step portion G 1 has almost no effect on the lean burn operation.
【００５２】つまり、拡大側ずれ状態（Ｃ）では、切欠
部１３Ｃの通過後に、吸入空気の流路が広がるため、吸
入空気の流速が低下してタンブル比が大きく低下するの
に対し、縮小側ずれ状態（Ａ）では、図３に示す如く、
段部Ｇ1により剥離領域Ｓが生じて吸入空気の流速が増
大し、その後の流路拡大による流速の減衰域が拡大側ず
れ状態（Ｃ）よりも下流側に移動するため、タンブル比
の低下が比較的少なくなるのである。That is, in the enlarged side shift state (C), the passage of the intake air is expanded after passing through the notch 13C, so that the flow velocity of the intake air is reduced and the tumble ratio is greatly reduced, while the reduction side is reduced. In the displaced state (A), as shown in FIG.
The stepped portion G 1 causes a separation region S to increase the flow velocity of the intake air, and the flow velocity attenuation region due to the subsequent expansion of the flow path moves to the downstream side of the expansion side shift state (C), so that the tumble ratio decreases. Is relatively small.
【００５３】次に、本実施例の作用について、説明す
る。まず、吸気ポート６の形成位置が基準位置にあって
位置ずれがない場合は、図１に示す如く、吸気通路２１
の第１の側部２１Ａ1側に、所定寸法δの段部２３が形
成されるが、この所定寸法δの段部２３が形成された状
態で、吸気制御弁２２等の仕様を予め設定するため、こ
のときのスワール比，タンブル比，リーン限界の空燃比
は、図４，図５中の記号☆と略同様の値となる。即ち、
この図１に示す基準位置関係において、その機関本体に
最適なスワール比，タンブル比が得られるように、切欠
部２２の形状等が設定してある。Next, the operation of this embodiment will be described. First, when the formation position of the intake port 6 is at the reference position and there is no displacement, as shown in FIG.
A step portion 23 having a predetermined dimension δ is formed on the first side portion 21A 1 side of the, and specifications of the intake control valve 22 and the like are preset in a state where the step portion 23 having the predetermined dimension δ is formed. Therefore, the swirl ratio, the tumble ratio, and the lean limit air-fuel ratio at this time have substantially the same values as the symbol ☆ in FIGS. 4 and 5. That is,
In the reference positional relationship shown in FIG. 1, the shape of the notch 22 and the like are set so that the optimum swirl ratio and tumble ratio can be obtained for the engine body.
【００５４】次に、図６に示す如く、吸気ポート６の形
成位置が切欠部２２Ｃ側に所定寸法δだけ横方向にずれ
た場合には、吸気ポート６の中心線Ｐと吸気通路２１の
中心線Ｐ1とが略一致すると共に、第１の側部２１Ａ1も
上流側開口部６Ｃの側部に略一致して、切欠部２２Ｃと
吸気ポート６との相対位置は変化するが、段部２３が第
１の側部２１Ａ1側から第２の側部２１Ａ2側に移り、こ
の結果、相対距離だけを所定寸法δだけ長くした場合と
同様の状態になるため、図４，図５中に記号●で示す如
く、スワール比，タンブル比等は殆ど低下しない。Next, as shown in FIG. 6, when the formation position of the intake port 6 is laterally displaced toward the notch 22C by a predetermined dimension δ, the center line P of the intake port 6 and the center of the intake passage 21 are separated. The line P 1 substantially coincides with the first side portion 21A 1 also substantially coincides with the side portion of the upstream opening 6C, and the relative position between the notch 22C and the intake port 6 changes, but the step portion 23 moves from the first side 21A 1 side to the second side 21A 2 side, and as a result, the same state as when the relative distance is lengthened by the predetermined dimension δ is obtained. As indicated by the symbol ●, the swirl ratio, tumble ratio, etc. hardly decrease.
【００５５】さらに、図６の状態とは逆に、図７に示す
如く、吸気ポート６の形成位置が切欠部２２Ｃとは反対
側に所定寸法δだけ横方向に位置ずれした場合は、吸気
ポート６の中心線Ｐと吸気通路２１の中心線Ｐ1とが２
δだけ離間すると共に、第１の側部２１Ａ1側の段部２
３の幅寸法もδから２δに拡大するため、第１の側部２
１Ａ1側に所定寸法δの段部２３が２個並んで形成され
たと等価な状態、即ち、図６に示す基準状態に対して、
所定寸法δの段部２３が新たに形成された状態となり、
スワール比等との間に、図３に示す縮小側ずれ状態
（Ａ）と同様の関係が成立する。従って、この場合も、
図４，図５中に、記号◇で示す如く、スワール比，タン
ブル比等は殆ど低下しない。Contrary to the state shown in FIG. 6, when the formation position of the intake port 6 is laterally displaced by a predetermined dimension δ on the side opposite to the notch 22C, as shown in FIG. 6 centerline P of the center line P 1 of the intake passage 21 2
The step portion 2 on the side of the first side portion 21A 1 is spaced apart by δ.
Since the width dimension of 3 also increases from δ to 2δ, the first side portion 2
In a state equivalent to the case where two step portions 23 having a predetermined dimension δ are formed side by side on the 1A 1 side, that is, with respect to the reference state shown in FIG.
A step 23 having a predetermined size δ is newly formed,
The same relationship as the reduction side shift state (A) shown in FIG. 3 is established between the swirl ratio and the like. Therefore, in this case as well,
As shown by the symbol ◇ in FIGS. 4 and 5, the swirl ratio, the tumble ratio, etc. hardly decrease.
【００５６】なお、図８に示す如く、吸気ポート６の形
成位置が寸法δ／２だけ切欠部２２Ｃ側に横ずれした場
合、即ち、図１に示す状態と図６に示す状態との中間の
状態で接続された場合も、スワール比，タンブル比等は
殆ど低下しない。As shown in FIG. 8, when the formation position of the intake port 6 is laterally displaced by the dimension δ / 2 toward the notch 22C, that is, an intermediate state between the state shown in FIG. 1 and the state shown in FIG. Even when connected by, the swirl ratio, the tumble ratio, etc. hardly decrease.
【００５７】このように構成される本実施例によれば、
以下の効果を奏する。According to the present embodiment configured as described above,
The following effects are obtained.
【００５８】第１に、吸気通路２１と吸気ポート６とを
基準位置関係で接続したときに、吸気通路２１の接続口
２１Ａの横方向両側部２１Ａ1，２１Ａ2のうち吸気制御
弁２２の切欠部２２Ｃ側に位置する第１の側部２１Ａ1
が吸気ポート６の上流側開口部６Ｃよりも所定寸法δだ
け横方向外側に位置するように設定したため、鋳造によ
る製造誤差によって、吸気ポート６の形成位置が切欠部
２２Ｃ側，切欠部２２Ｃの反対側のいずれの方向にずれ
た場合でも、スワール比，タンブル比，リーン限界の空
燃比が殆ど低下せず、実質的に、適切なスワール比，タ
ンブル比を確保することができる。この結果、吸気ポー
ト６の形成位置が多少ずれた場合でも、この位置ずれに
よる影響を排除して、安定した希薄燃焼運転時の運転性
を確保することができ、機関毎の運転性のばらつきを大
幅に低減することができる。First, when the intake passage 21 and the intake port 6 are connected in the reference positional relationship, the cutout of the intake control valve 22 in the laterally opposite side portions 21A 1 and 21A 2 of the connection port 21A of the intake passage 21. The first side portion 21A 1 located on the side of the portion 22C
Is set to be laterally outward by a predetermined dimension δ from the upstream opening 6C of the intake port 6, so that the formation position of the intake port 6 is opposite to the cutout 22C side and the cutout 22C due to a manufacturing error due to casting. Even if it shifts to either side, the swirl ratio, the tumble ratio, and the lean-limit air-fuel ratio hardly decrease, and it is possible to substantially secure the appropriate swirl ratio and tumble ratio. As a result, even if the formation position of the intake port 6 is slightly deviated, it is possible to eliminate the influence of this misregistration and ensure stable operability during lean combustion operation, and to reduce the operability of each engine. It can be significantly reduced.
【００５９】第２に、吸気通路２１の幅Ｗ1を吸気ポー
ト６の幅Ｗよりも所定寸法δだけ大きく形成した上で、
第１の側部２１Ａ1が上流側開口部６Ｃよりも所定寸法
δだけ横方向外側に位置するように接続する構成とした
ため、吸気通路２１を吸気ポート６の形成位置ずれを吸
収できる範囲内で必要最低限の大きさに形成することが
できる。この結果、吸気通路２１単体の製造コストの増
大を抑制しつつ、吸気ポート６の形成位置ずれによる希
薄燃焼運転時の影響を効果的に排除することができる。Secondly, after forming the width W 1 of the intake passage 21 larger than the width W of the intake port 6 by a predetermined dimension δ,
Since the first side portion 21A 1 is connected to the upstream side opening portion 6C so as to be positioned laterally outward by the predetermined dimension δ, the intake passage 21 is within a range capable of absorbing the formation position deviation of the intake port 6. It can be formed to the minimum required size. As a result, while suppressing an increase in the manufacturing cost of the intake passage 21 alone, it is possible to effectively eliminate the influence of the displacement of the formation position of the intake port 6 during the lean combustion operation.
【００６０】第３に、所定寸法δを鋳造成型による吸気
ポート６の製造公差の最大値に設定したため、常に、吸
気ポート６の位置ずれを吸収でき、吸気装置全体の製造
コスト等を大幅に低減することができる。Thirdly, since the predetermined size δ is set to the maximum value of the manufacturing tolerance of the intake port 6 formed by casting, the positional deviation of the intake port 6 can always be absorbed, and the manufacturing cost of the intake device as a whole is greatly reduced. can do.
【００６１】次に、図９に基づいて、本発明の第２の実
施例を説明する。なお、本実施例では、上述した第１の
実施例と同一の構成要素に同一の符号を付し、その説明
を省略するものとする。本実施例の特徴は、段部に面取
り部を設けた点にある。Next, a second embodiment of the present invention will be described with reference to FIG. In this embodiment, the same components as those in the first embodiment described above are designated by the same reference numerals, and the description thereof will be omitted. The feature of this embodiment is that a chamfer is provided on the step.
【００６２】即ち、図９は、本実施例による内燃機関の
吸気装置の要部を拡大して示す構成説明図であって、本
実施例による段部３１は、第１の実施例で述べた段部２
３と同様に、吸気通路２１の接続口２１Ａと吸気ポート
６の上流側開口部６Ｃとが基準位置関係で接続されたと
きに、接続口２１Ａの第１の側部２１Ａ1が上流側開口
部６Ｃよりも所定寸法δだけ横方向外側に位置すること
により形成されるものの、段部３１の内周側縁部には曲
面状の面取り部３２が設けられている。That is, FIG. 9 is an enlarged view of the construction of the main part of the intake system for an internal combustion engine according to this embodiment, and the step portion 31 according to this embodiment has been described in the first embodiment. Step 2
Similar to 3, when the connection port 21A of the intake passage 21 and the upstream opening 6C of the intake port 6 are connected in the reference positional relationship, the first side 21A 1 of the connection port 21A is connected to the upstream opening. A curved chamfered portion 32 is provided on the inner peripheral edge of the step portion 31, although the chamfered portion 32 is formed by being positioned laterally outward by a predetermined dimension δ from 6C.
【００６３】かくして、このように構成される本実施例
でも、上述した第１の実施例と同様の効果を得ることが
できる。これに加えて、本実施例では、段部３１に面取
り部３２を設ける構成としたため、吸気制御弁２２の切
欠部２２Ｃを通過した吸入空気を滑らかに第１のポート
部６Ａ内に導くことができ、より一層適切なスワール
比，タンブル比を得ることができる。つまり、吸気ポー
ト６の形成位置は、基準位置を中心として、左右両側に
最大δだけずれる可能性があるが、基準位置で形成され
る確率が最も高いため、かかる基準状態、即ち基準位置
関係でのスワール比，タンブル比を最適化するのが好ま
しい。そこで、本実施例では、吸気ポート６と吸気通路
２１とが基準位置関係で接続された場合に、吸入空気を
滑らかに第１のポート部６Ａに誘導できるように、段部
３１に面取り部３２を設けているのである。Thus, in this embodiment having such a configuration, the same effect as that of the above-described first embodiment can be obtained. In addition to this, since the chamfered portion 32 is provided in the step portion 31 in the present embodiment, the intake air that has passed through the notch portion 22C of the intake control valve 22 can be smoothly guided into the first port portion 6A. Therefore, a more appropriate swirl ratio and tumble ratio can be obtained. In other words, the formation position of the intake port 6 may be shifted by δ on the left and right sides with respect to the reference position by the maximum, but since the probability of being formed at the reference position is the highest, in such a reference state, that is, the reference position relationship. It is preferable to optimize the swirl ratio and the tumble ratio of. Therefore, in this embodiment, when the intake port 6 and the intake passage 21 are connected in the reference positional relationship, the chamfered portion 32 is provided on the stepped portion 31 so that the intake air can be smoothly guided to the first port portion 6A. Is provided.
【００６４】なお、前記各実施例では、吸気通路２１を
略楕円形状に形成する場合を例に挙げて説明したが、こ
れに限らず、略円形状等に形成してもよい。In each of the above-mentioned embodiments, the case where the intake passage 21 is formed in a substantially elliptical shape has been described as an example, but the present invention is not limited to this, and it may be formed in a substantially circular shape or the like.
【００６５】[0065]
【発明の効果】以上詳述した通り、本発明に係る内燃機
関の吸気装置によれば、製造誤差によって、吸気ポート
の形成位置が切欠部側，切欠部の反対側のいずれの方向
にずれた場合でも、実質的に、適切なスワール比，タン
ブル比を確保できるため、吸気ポートの形成位置のずれ
による影響を排除して、安定した希薄燃焼運転時の運転
性を確保でき、機関毎の運転性のばらつきを低減するこ
とができる。As described in detail above, according to the intake system for an internal combustion engine according to the present invention, the formation position of the intake port is deviated in either the notch side or the opposite side of the notch due to a manufacturing error. Even in such a case, the swirl ratio and tumble ratio can be substantially secured, so the influence of the deviation of the intake port formation position can be eliminated, and stable operability during lean burn operation can be secured, and the operation of each engine It is possible to reduce the variation in sex.
【００６６】また、吸気通路の幅を吸気ポートの幅より
も所定寸法だけ大きく形成して、第１の側部が上流側開
口部よりも所定寸法だけ横方向外側に位置するように接
続すると共に、製造公差の最大値を所定寸法と設定した
ため、吸気ポートの形成位置ずれを吸収できる範囲内
で、吸気通路を必要最低限の大きさに形成することがで
き、製造コストの増大を抑制しつつ、吸気ポートの形成
位置ずれによる希薄燃焼運転時の影響を効果的に排除で
きる。Further, the width of the intake passage is formed larger than the width of the intake port by a predetermined dimension, and the first side portion is connected so as to be located laterally outside by a predetermined dimension from the upstream opening. Since the maximum value of the manufacturing tolerance is set to the predetermined size, the intake passage can be formed to the necessary minimum size within the range in which the formation position deviation of the intake port can be absorbed, while suppressing the increase of the manufacturing cost. It is possible to effectively eliminate the influence of lean combustion operation due to displacement of the formation position of the intake port.
【００６７】さらに、接続口の第１の側部と吸気ポート
の上流側開口部との間に形成される段部に面取り部を設
ける構成としたため、吸気ポートと吸気通路とを基準位
置関係で接続したときに、切欠部を通過した吸入空気を
滑らかに第１のポート部に流入させることができ、これ
により、一層適切なスワール比，タンブル比を得ること
ができる。Further, since the chamfered portion is provided in the step portion formed between the first side portion of the connection port and the upstream side opening portion of the intake port, the intake port and the intake passage have a reference positional relationship. When connected, the intake air that has passed through the cutout portion can be made to smoothly flow into the first port portion, whereby a more appropriate swirl ratio and tumble ratio can be obtained.
【図１】本発明の第１の実施例に係る内燃機関の吸気装
置の全体構成を示す構成説明図である。FIG. 1 is a configuration explanatory diagram showing an overall configuration of an intake device for an internal combustion engine according to a first embodiment of the present invention.
【図２】基準位置関係において、吸気通路の接続口側か
ら吸気ポートの上流側開口部を見たときの構成説明図で
ある。FIG. 2 is a configuration explanatory diagram when the upstream opening of the intake port is viewed from the connection port side of the intake passage in the reference positional relationship.
【図３】従来技術のものにおいて、吸気ポートの形成位
置ずれの各態様を示す説明図である。FIG. 3 is an explanatory diagram showing each mode of displacement of the formation position of the intake port in the prior art.
【図４】位置ずれ状態等とスワール比，タンブル比との
関係を示す特性図である。FIG. 4 is a characteristic diagram showing a relationship between a position shift state and the like, and a swirl ratio and a tumble ratio.
【図５】位置ずれ状態等とリーン限界空燃比との関係を
示す特性図である。FIG. 5 is a characteristic diagram showing a relationship between a position shift state and the lean limit air-fuel ratio.
【図６】実施例による吸気ポートが切欠部側に所定寸法
だけずれた状態を示す説明図である。FIG. 6 is an explanatory diagram showing a state in which the intake port according to the embodiment is displaced toward the cutout portion by a predetermined dimension.
【図７】吸気ポートが切欠部の反対側に所定寸法だけず
れた状態を示す図６と同様の説明図である。FIG. 7 is an explanatory view similar to FIG. 6, showing a state in which the intake port is displaced on the side opposite to the cutout portion by a predetermined dimension.
【図８】吸気ポートが切欠部側に所定寸法の半分だけず
れた状態を示す図６と同様の説明図である。FIG. 8 is an explanatory view similar to FIG. 6, showing a state where the intake port is displaced toward the cutout portion by half a predetermined dimension.
【図９】本発明の第２の実施例に係る内燃機関の吸気装
置の要部を拡大して示す構成説明図である。FIG. 9 is a structural explanatory view showing an enlarged main part of an intake device for an internal combustion engine according to a second embodiment of the present invention.
【図１０】従来技術による内燃機関の吸気装置の全体構
成を示す構成説明図である。FIG. 10 is a structural explanatory view showing an overall structure of an intake device for an internal combustion engine according to a conventional technique.
【図１１】図１０中の要部を拡大して示す断面図であ
る。11 is a cross-sectional view showing an enlarged main part in FIG.
【図１２】吸気制御弁の開閉を制御するための制御マッ
プの説明図である。FIG. 12 is an explanatory diagram of a control map for controlling opening / closing of the intake control valve.
１…シリンダ ４…シリンダヘッド ６…吸気ポート ６Ａ…第１のポート部 ６Ｂ…第２のポート部 ６Ｃ…上流側開口部 ２１…吸気通路 ２１Ａ…接続口 ２１Ａ1…第１の側部 ２２…吸気制御弁 ２２Ｃ…切欠部 ２３，３１…段部 δ…所定寸法DESCRIPTION OF SYMBOLS 1 ... Cylinder 4 ... Cylinder head 6 ... Intake port 6A ... 1st port part 6B ... 2nd port part 6C ... Upstream side opening 21 ... Intake passage 21A ... Connection port 21A 1 ... 1st side part 22 ... Intake Control valve 22C ... Notch portion 23, 31 ... Step portion δ ... Predetermined dimension
Claims (3)
けられ、下流側が二股に分岐して一対のポート部となっ
た吸気ポートと、この吸気ポートの上流側開口部に接続
された吸気通路と、この吸気通路内に回動可能に設けら
れ、前記一対のポート部のうち第１のポート部に対応す
る切欠部が弁体の横方向に形成された吸気制御弁とを有
する内燃機関の吸気装置であって、 前記吸気通路と前記吸気ポートとを基準位置関係で接続
したときに、前記吸気通路の接続口の横方向両側部のう
ち前記吸気制御弁の切欠部側に位置する第１の側部が前
記吸気ポートの上流側開口部よりも所定寸法だけ横方向
外側に位置するように設定したことを特徴とする内燃機
関の吸気装置。1. An intake port provided on a cylinder head for covering a cylinder, the downstream side being bifurcated into a pair of port parts, and an intake passage connected to an upstream side opening part of the intake port. An intake device for an internal combustion engine, which includes an intake control valve rotatably provided in the intake passage and having a notch corresponding to the first port of the pair of ports formed laterally of the valve body. A first side located on the notch side of the intake control valve of the laterally opposite side portions of the connection port of the intake passage when the intake passage and the intake port are connected in a reference positional relationship. The intake device for an internal combustion engine is characterized in that the portion is located laterally outside by a predetermined dimension from the upstream opening of the intake port.
造成型によって設けられ、下流側が二股に分岐して一対
のポート部となった吸気ポートと、この吸気ポートの上
流側開口部に接続口を介して接続され、少なくとも該接
続口が機械加工によって成形された吸気通路と、この吸
気通路内に前記接続口の近傍に位置して回動可能に設け
られ、前記一対のポート部のうち第１のポート部に対応
する切欠部が弁体の横方向に形成された吸気制御弁とを
有する内燃機関の吸気装置であって、 前記吸気通路の接続口の横幅を前記吸気ポートの上流側
開口部の横幅よりも所定寸法だけ大きく形成すると共
に、 前記吸気制御弁の切欠部を前記吸気ポートの中心線から
前記所定寸法だけ偏心させて弁体の横方向に形成し、 前記吸気通路と前記吸気ポートとを基準位置関係で接続
したときに、前記吸気通路の接続口の横方向両側部のう
ち前記吸気制御弁の切欠部側に位置する第１の側部が前
記吸気ポートの上流側開口部よりも前記所定寸法だけ横
方向外側に位置するように設定し、 かつ、前記所定寸法は、前記吸気ポートの製造公差の最
大値に設定したことを特徴とする内燃機関の吸気装置。2. An intake port, which is provided on a cylinder head for covering a cylinder by casting and has a downstream side bifurcated into a pair of port parts, and an upstream side opening part of the intake port via a connection port. Connected to each other and at least the connection port is formed by machining, and an intake passage that is rotatably provided in the intake passage in the vicinity of the connection port. An intake device for an internal combustion engine, comprising: an intake control valve having a notch portion corresponding to a port portion formed in a lateral direction of a valve body, wherein a lateral width of a connection port of the intake passage is set to an upstream side opening portion of the intake port. The intake control valve is formed to be larger than the lateral width by a predetermined dimension, and the cutout portion of the intake control valve is formed eccentrically from the center line of the intake port by the predetermined dimension in the lateral direction of the valve body to form the intake passage and the intake port. To When connected in the reference positional relationship, the first side portion located on the side of the cutout portion of the intake control valve in the laterally opposite side portions of the connection port of the intake passage is located above the upstream opening portion of the intake port. An intake device for an internal combustion engine, wherein the intake device is set to be located laterally outward by a predetermined size, and the predetermined size is set to a maximum value of a manufacturing tolerance of the intake port.
位置関係で接続したときに、前記第１の側部と前記吸気
ポートの上流側開口部との間に形成される段部に面取り
部を設けたことを特徴とする請求項１又は請求項２に記
載の内燃機関の吸気装置。3. A chamfered portion formed on a step formed between the first side portion and an upstream side opening of the intake port when the intake passage and the intake port are connected in a reference positional relationship. The intake device for an internal combustion engine according to claim 1 or 2, further comprising:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7108363A JPH08303250A (en) | 1995-05-02 | 1995-05-02 | Intake device for internal combustion engine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7108363A JPH08303250A (en) | 1995-05-02 | 1995-05-02 | Intake device for internal combustion engine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH08303250A true JPH08303250A (en) | 1996-11-19 |
Family
ID=14482857
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7108363A Pending JPH08303250A (en) | 1995-05-02 | 1995-05-02 | Intake device for internal combustion engine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH08303250A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000220460A (en) * | 1999-01-28 | 2000-08-08 | Hitachi Ltd | Cylinder injection type internal combustion engine |
-
1995
- 1995-05-02 JP JP7108363A patent/JPH08303250A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000220460A (en) * | 1999-01-28 | 2000-08-08 | Hitachi Ltd | Cylinder injection type internal combustion engine |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3003339B2 (en) | Intake system for fuel injection type internal combustion engine | |
| JP2639721B2 (en) | Combustion chamber of internal combustion engine | |
| JPH07119472A (en) | Intake device for engine | |
| JPH048610B2 (en) | ||
| EP1464806A2 (en) | Intake apparatus for internal combustion engine | |
| US4951642A (en) | Combustion chamber of internal combustion engine | |
| JPH08303250A (en) | Intake device for internal combustion engine | |
| WO2022176862A1 (en) | Air intake structure for internal combustion engine | |
| US10072605B2 (en) | Internal combustion engine | |
| JPS58135321A (en) | Air intake device for internal-combustion engine | |
| JP2639720B2 (en) | Intake control device for internal combustion engine | |
| JPS61201826A (en) | Intake device of internal-combustion engine | |
| JP3318359B2 (en) | Engine intake control device | |
| JPH0415939Y2 (en) | ||
| JP3567295B2 (en) | Intake device for internal combustion engine | |
| JP2802308B2 (en) | 4-cylinder engine intake system | |
| JP2004143954A (en) | Air inlet port structure of internal combustion engine | |
| JPS588902Y2 (en) | engine intake system | |
| JPH0346183Y2 (en) | ||
| JPH09287460A (en) | Intake system for internal combustion engine | |
| JPH07279751A (en) | Intake device for internal combustion engine | |
| JPS597539Y2 (en) | Double intake internal combustion engine | |
| JPH07247917A (en) | Structure of exhaust reflux passage of engine | |
| JPH0236905Y2 (en) | ||
| JPH1037752A (en) | Intake device for internal combustion engine |