JPH086570B2 - Internal combustion engine - Google Patents

Internal combustion engine

Info

Publication number
JPH086570B2
JPH086570B2 JP2213376A JP21337690A JPH086570B2 JP H086570 B2 JPH086570 B2 JP H086570B2 JP 2213376 A JP2213376 A JP 2213376A JP 21337690 A JP21337690 A JP 21337690A JP H086570 B2 JPH086570 B2 JP H086570B2
Authority
JP
Japan
Prior art keywords
intake
valve
opening
minute
side rocker
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 - Fee Related
Application number
JP2213376A
Other languages
Japanese (ja)
Other versions
JPH0494407A (en
Inventor
千早 杉本
毅 岩田
龍司 松門
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Honda Motor Co Ltd
Original Assignee
Honda Motor Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Honda Motor Co Ltd filed Critical Honda Motor Co Ltd
Priority to JP2213376A priority Critical patent/JPH086570B2/en
Priority to US07/742,831 priority patent/US5209201A/en
Priority to CA002048913A priority patent/CA2048913C/en
Priority to AT91307403T priority patent/ATE124108T1/en
Priority to DE69110573T priority patent/DE69110573T2/en
Priority to EP91307403A priority patent/EP0470869B1/en
Priority to ES91307403T priority patent/ES2076476T3/en
Publication of JPH0494407A publication Critical patent/JPH0494407A/en
Publication of JPH086570B2 publication Critical patent/JPH086570B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Landscapes

  • Valve-Gear Or Valve Arrangements (AREA)
  • Valve Device For Special Equipments (AREA)
  • Output Control And Ontrol Of Special Type Engine (AREA)
  • Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)

Description

【発明の詳細な説明】 A.発明の目的 （１） 産業上の利用分野 本発明は、主として機関の低速運転域での吸入行程で
一対の吸気弁のうち一方の吸気弁を開閉駆動するための
開閉作動用カム、ならびに他方の吸気弁を実質的な休止
状態とする程度の微小量だけ開くための微小作動用カム
を含む複数のカムが設けられたカムシャフトを備える動
弁装置には、両吸気弁の作動特性を機関の運転状態に応
じて切換可能な弁作動特性切換手段が設けられ、前記一
対の吸気弁に連なる吸気系に対し吸入行程で燃料噴射を
行う燃料噴射弁を備えてなる、内燃機関に関する。DETAILED DESCRIPTION OF THE INVENTION A. Objects of the Invention (1) Field of Industrial Application The present invention is mainly for opening and closing one of a pair of intake valves in an intake stroke in a low speed operation range of an engine. The valve operating device having a cam shaft provided with a plurality of cams including the opening / closing operation cam, and the minute operation cam for opening the other intake valve by a minute amount to a substantially rest state, A valve operating characteristic switching means that can switch the operating characteristics of both intake valves according to the operating state of the engine is provided, and a fuel injection valve that injects fuel in an intake stroke to an intake system connected to the pair of intake valves is provided. It relates to an internal combustion engine.

（２） 従来の技術 従来、一対の吸気弁のうちの一方を機関低速運転域で
微小量だけリフトさせるようにして、機関低速運転域で
の燃費の増大を防止するとともに実質閉止状態にある吸
気ポートの燃料滞留を回避して燃料を安定性を図るよう
にした内燃機関が、例えば実開昭60−195913号公報等に
より開示されている。(2) Conventional Technology In the related art, one of a pair of intake valves is lifted by a small amount in the engine low speed operation range to prevent an increase in fuel consumption in the engine low speed operation range and to substantially prevent intake air from being closed. An internal combustion engine which avoids fuel retention in a port and stabilizes fuel is disclosed in, for example, Japanese Utility Model Laid-Open No. 60-195913.

（３） 発明が解決しようとする課題 上記従来のもののように、主として機関の低速運転域
で一方の吸気弁を開閉作動させ、他方の吸気弁を実質的
に閉弁状態となる程度に僅かに開くようにすると、実質
的には一方の吸気弁側のみから燃焼室に混合気が流入す
ることにより燃焼室内にスワールを形成して燃焼性を向
上するとともに、他方の吸気弁側の吸気ポートへの燃料
滞留および他方の吸気弁の弁座への固着を回避すること
が可能となる。(3) Problems to be Solved by the Invention Like the above-mentioned conventional one, the intake valve is slightly opened and closed so that one intake valve is opened and closed mainly in the low speed operation range of the engine, and the other intake valve is substantially closed. When opened, the air-fuel mixture practically flows from only one intake valve side into the combustion chamber to form a swirl in the combustion chamber to improve combustibility and to the intake port on the other intake valve side. It is possible to avoid the fuel accumulation and the sticking of the other intake valve to the valve seat.

しかるに、他方の吸気弁を僅かに開くタイミングによ
っては、一方の吸気弁側からの混合気流入によるスワー
ル生成を阻害するおそれがあり、また燃料噴射弁の開弁
タイミングによっては、前記他方の吸気弁が僅かに開く
ことに関係して良好な層状給気を達成し得なくなるおそ
れもあり、従って他方の吸気弁を僅かに開くタイミング
や燃料噴射弁を開くタイミングをそれぞれ適切に選ぶ必
要がある。However, depending on the timing of opening the other intake valve slightly, there is a risk that swirl generation due to air-fuel mixture inflow from one intake valve side may be hindered, and depending on the opening timing of the fuel injection valve, the other intake valve It may not be possible to achieve a good stratified charge due to the slight opening of the intake valve, so that it is necessary to appropriately select the timing of slightly opening the other intake valve and the timing of opening the fuel injection valve.

また、弁作動特性切換手段により弁作動特性を切換え
る際にその切換が失敗することがあり、前記他方の吸気
弁が実質的に休止している状態から開閉作動用カムで開
閉駆動すべく切換える際に切換失敗が生じたときには、
微小作動用カムにより吸気弁の閉弁方向の作動を規制し
て吸気弁が弁座に衝撃的に衝突することを避けることが
可能であるが、微小作動用カムの開角時期によっては、
前記切換失敗時に磁気弁が比較的高リフトまで開弁方向
に作動している途中から反転して閉弁方向に作動して弁
座に衝撃的に衝突することがある。Further, when switching the valve operating characteristics by the valve operating characteristic switching means, the switching may fail, and when switching from the state in which the other intake valve is substantially inactive to the opening / closing driving by the opening / closing operation cam. When switching fails in
It is possible to prevent the intake valve from colliding with the valve seat by impact by restricting the operation of the intake valve in the valve closing direction by the minute operation cam, but depending on the opening angle of the minute operation cam,
When the switching fails, the magnetic valve may reverse from the middle of operating in the valve opening direction up to a comparatively high lift and may operate in the valve closing direction to collide with the valve seat.

本発明は、かかる事情に鑑みてなされたものであり、
一方の吸気弁からのスワール生成に極力支障を来さない
ようにするとともに弁作動特性切換手段の切換失敗時に
吸気弁の衝撃緩和を果たし得るように、微小作動用カム
による吸気弁の開き作動タイミングを定めると共に、こ
の吸気弁の僅かな開き動作によっても良好な層状給気が
達成されてトルク変動が効果的に抑えられるように燃料
噴射弁の燃料噴射終了時期を定めた内燃機関を提供する
ことを目的とする。The present invention has been made in view of such circumstances,
The timing of opening the intake valve by the minute actuation cam so that the swirl generation from one intake valve is not hindered as much as possible and the impact of the intake valve can be mitigated when the valve operation characteristic switching means fails to switch. And to provide an internal combustion engine in which the fuel injection end timing of the fuel injection valve is determined such that good stratified charge can be achieved and the torque fluctuation can be effectively suppressed even by a slight opening operation of the intake valve. With the goal.

B.発明の構成 （１） 課題を解決するための手段 上記目的を達成するために、請求項１に記載の発明に
よれば、微小作動用カムは、主として機関の低速運転域
での開閉作動用カムによる一方の吸気弁の開弁リフト曲
線の開角中心時期よりも遅角側に開角中心時期を有する
とともに前記開弁リフト曲線のクランク角に沿う終端の
緩衝曲線部近傍に終端時期を有する微小リフト曲線で他
方の吸気弁を開くべく形成され、実質的に前記一方の吸
気弁のみが開閉作動している運転状態での燃料噴射弁の
燃料噴射終了時期が吸入行程前半に設定される。B. Structure of the Invention (1) Means for Solving the Problems In order to achieve the above object, according to the invention described in claim 1, the minute actuation cam mainly opens and closes in a low speed operation range of the engine. The intake cam has an opening center time on the side of the opening angle of the opening lift curve of one intake valve, and an ending time near the end of the buffer curve portion along the crank angle of the opening lift curve. The intake valve is formed to open the other intake valve with a small lift curve, and the fuel injection end timing of the fuel injection valve is set in the first half of the intake stroke in the operating state in which only the one intake valve is substantially opened and closed. .

また請求項２に記載の発明によれば、上記請求項１の
発明の構成に加えて、微小作動用カムによる微小リフト
曲線の最大リフト部は、開閉作動用カムによる開弁リフ
ト曲線の最大リフト部よりもクランク角に沿う後方側に
設定され、更に請求項第項記載の発明によれば、上記
請求項１又は２の発明の構成に加えて、動弁装置は、カ
ムシャフトの各カムおよび一対の吸気弁間で相互に隣接
して設けられる複数の弁駆動部材を備え、弁作動特性切
換手段は、隣接した弁駆動部材相互の連結および連結解
除を切換可能に構成される。According to the invention of claim 2, in addition to the configuration of the invention of claim 1, the maximum lift portion of the minute lift curve by the minute operation cam is the maximum lift of the valve opening lift curve by the opening / closing operation cam. According to the invention of claim 1, further to the configuration of the invention of claim 1 or 2, in addition to the configuration of the invention of claim 1 or 2, A plurality of valve drive members provided adjacent to each other between the pair of intake valves are provided, and the valve operating characteristic switching means is configured to be able to switch connection and disconnection between the adjacent valve drive members.

（２） 作用 上記請求項１の発明の構成によれば、主として機関の
低速運転域における吸入行程で開閉作動用カムにより開
閉駆動される一方の吸気弁よりも遅れて微小カムにより
他方の吸気弁をわずかに開くようにし、他方の吸気弁が
わずかに開くことによるスワール生成への悪影響を極力
回避することができ、また弁作動特性切換手段による弁
作動特性切換が失敗したときにも、他方の吸気弁が比較
的高リフトまで開弁した後には微小作動用カムの規制に
より弁座に直接衝突することが回避される。(2) Operation According to the configuration of the invention of the above-mentioned claim 1, the other intake valve is driven by the minute cam later than the one intake valve which is driven to be opened / closed by the opening / closing cam mainly in the intake stroke in the low speed operation range of the engine. Can be opened slightly, and the adverse effect on swirl generation due to the slight opening of the other intake valve can be avoided as much as possible, and when the valve operation characteristic switching by the valve operation characteristic switching means fails, the other After the intake valve is opened to a relatively high lift, direct collision with the valve seat is avoided by regulating the minute actuation cam.

しかも燃料噴射終了時期を、前記他方の吸気弁が殆ど
開かれていない吸入行程の前半に設定することにより、
良好な層状給気が達成されてトルク変動を極力抑えるこ
とができる。Moreover, by setting the fuel injection end timing in the first half of the intake stroke in which the other intake valve is almost not opened,
Good stratified air supply is achieved, and torque fluctuations can be suppressed as much as possible.

また特に上記請求項２の発明の構成によれば、微小作
動用カムによる微小リフト曲線の最大リフト部を開閉作
動用カムによる開弁リフト曲線の最大リフト部よりもク
ランク角に沿う後方側に設定することにより、上記請求
項１の発明の作用がより促進される。Further, in particular, according to the configuration of the invention of claim 2, the maximum lift portion of the minute lift curve by the minute operation cam is set to the rear side along the crank angle with respect to the maximum lift portion of the valve opening lift curve by the opening / closing operation cam. By doing so, the action of the invention of claim 1 is further promoted.

（３） 実施例 以下、図面により本発明の実施例について説明する。(3) Examples Hereinafter, examples of the present invention will be described with reference to the drawings.

第１図ないし第７図は本発明の一実施例を示すもので
あり、第１図は全体構成図、第２図は第１図のII−II線
に沿う部分切欠き拡大平面図、第３図は吸気弁作動状態
と燃料噴射時期との関係を示す図、第４図は燃料噴射時
期の燃料安定性に及ぼす影響の実験結果を示すグラフ、
第５図は燃料噴射終了時期のトルク変動率に及ぼす影響
を実験結果を示すグラフ、第６図は実質休止状態にある
吸気弁の開角中心時期の相違による燃焼限界に及ぼす影
響の実験結果を示すグラフ、第７図は実質休止状態にあ
る吸気弁の開角中心時期の相違によるトルク変動率、燃
費および排ガス性状に及ぼす影響の実験結果を示すグラ
フである。1 to 7 show an embodiment of the present invention. FIG. 1 is an overall configuration diagram, FIG. 2 is an enlarged plan view of a partial notch along line II-II of FIG. FIG. 3 is a diagram showing the relationship between the intake valve operating state and fuel injection timing, and FIG. 4 is a graph showing experimental results of the effect of fuel injection timing on fuel stability.
FIG. 5 is a graph showing the experimental result of the influence of the fuel injection end timing on the torque fluctuation rate, and FIG. 6 is the experimental result of the influence on the combustion limit due to the difference in the opening angle center timing of the intake valve in the substantially idle state. The graph shown in FIG. 7 is a graph showing the experimental results of the influence on the torque fluctuation rate, the fuel consumption, and the exhaust gas property due to the difference in the center timing of the opening angle of the intake valve in the substantially resting state.

先ず第１図において、SOHC型多気筒内燃機関における
機関本体の主要部を構成すべく、シリンダブロック１の
上面にシリンダヘッド２が結合され、シリンダブロック
１に設けられた複数のシリンダ３には上面に凹部4aを有
するピストン４が摺動可能にそれぞれ嵌合され、それら
のピストン４の上面およびシリンダヘッド２間に燃焼室
５がそれぞれ形成される。First, in FIG. 1, a cylinder head 2 is coupled to an upper surface of a cylinder block 1 and upper surfaces of a plurality of cylinders 3 provided in the cylinder block 1 so as to constitute a main part of an engine body in an SOHC type multi-cylinder internal combustion engine. Pistons 4 each having a recess 4a are slidably fitted therein, and combustion chambers 5 are formed between the upper surfaces of the pistons 4 and the cylinder head 2.

燃焼室５の天井面に開口するようにして、一対の吸気
弁口６と一対の排気弁口７とがシリンダヘッド２に設け
られる。またシリンダヘッド２には、その一側面に開口
する単一の吸気開口端９から分岐して前記一対の吸気弁
口６に個別に連なる一対の吸気ポート８と、前記一対の
排気弁口７に個別に連なるとともにシリンダヘッド２の
他側面に開口した単一の排気開口端11に共通に連なる一
対の排気ポート10とが設けられる。両吸気弁口６を個別
に開閉可能な一対の吸気弁VI1,VI2は、シリンダヘッド
２に配設した一対のガイド筒12にそれぞれ摺動可能に嵌
合されており、各ガイド筒12から突出した各吸気弁VI1,
VI2の上端部にそれぞれ固定されたリテーナ13とシリン
ダヘッド２との間には各吸気弁VI1,VI2を囲繞するコイ
ル状の弁バネ14がそれぞれ介設され、それらの弁ばね14
により各吸気弁VI1,VI2は上方すなわち閉弁方向に付勢
される。さらに両排気弁口７を個別に開閉可能な一対の
排気弁VE1,VE2は、シリンダヘッド２に配設された一対
のガイド筒15にそれぞれ摺動可能に嵌合されており、各
ガイド筒15から突出した各排気弁VE1,VE2の上端部にそ
れぞれ固定されたリテーナ16とシリンダヘッド２との間
には各排気弁VE1,VE2を囲繞するコイル状の弁ばね17が
それぞれ介設され、それらの弁ばね17により各排気弁V
E1,VE2は上方すなわち閉弁方向に付勢される。A pair of intake valve openings 6 and a pair of exhaust valve openings 7 are provided in the cylinder head 2 so as to open to the ceiling surface of the combustion chamber 5. Further, the cylinder head 2 has a pair of intake ports 8 branching from a single intake opening end 9 opening on one side surface thereof and continuously connected to the pair of intake valve openings 6, and a pair of exhaust valve openings 7. A pair of exhaust ports 10 that are individually connected and that are commonly connected to a single exhaust opening end 11 that is opened on the other side surface of the cylinder head 2 are provided. A pair of intake valves V I1 and V I2 that can open and close both intake valve openings 6 individually are slidably fitted to a pair of guide cylinders 12 arranged on the cylinder head 2, respectively. From each intake valve V I1 ,
Between the retainer 13 fixed to the upper end of V I2 and the cylinder head 2, coiled valve springs 14 surrounding the intake valves V I1 and V I2 are provided, respectively.
As a result, the intake valves V I1 and V I2 are urged upward, that is, in the valve closing direction. Further, a pair of exhaust valves V E1 and V E2 capable of individually opening and closing both exhaust valve openings 7 are slidably fitted to a pair of guide cylinders 15 arranged on the cylinder head 2, respectively. Between the retainer 16 fixed to the upper ends of the exhaust valves V E1 and V E2 protruding from the cylinder 15 and the cylinder head 2, there are coiled valve springs 17 surrounding the exhaust valves V E1 and V E2. Each exhaust valve V is installed by its respective valve spring 17.
E1 and V E2 are urged upward, that is, in the valve closing direction.

第２図を併せて参照して、両吸気弁VI1,VI2および両
排気弁VE1,VE2に動弁装置18が連結される。この動弁装
置18は、図示しないクランクシャフトに1/2の減速比で
連動、連結される単一のカムシャフト19と、カムシャフ
ト19の回転運動を両吸気弁VI1,VI2の開閉運動に変換す
るための弁駆動部材としての第１および第２吸気側ロッ
カアーム20,21と、前記カムシャフト19の回転運動を両
排気弁VE1,VE2の開閉運動に変換するための第１および
第２排気側ロッカアーム22,23とを備える。Referring also to FIG. 2 , a valve train 18 is connected to both intake valves V I1 and V I2 and both exhaust valves V E1 and V E2 . The valve operating device 18 rotates a single camshaft 19 linked to a crankshaft (not shown) at a speed reduction ratio of 1/2 and rotational movement of the camshaft 19 to open and close both intake valves V I1 and V I2 . The first and second intake-side rocker arms 20 and 21 as valve drive members for converting to and the first and second rotational motions of the camshaft 19 to the opening and closing motions of both exhaust valves V E1 and V E2. The second exhaust-side rocker arms 22 and 23 are provided.

カムシャフト19は、シリンダヘッド２と、前記クラン
クシャフト19の軸線に沿うシリンダ３の両側で該シリン
ダヘッド２上にそれぞれ結合されるホルダ24とで、シリ
ンダ３の軸線と直交する水平な軸線を有しながら回転自
在に支承される。The camshaft 19 includes a cylinder head 2 and holders 24 that are respectively coupled to the cylinder head 2 on both sides of the cylinder 3 along the axis of the crankshaft 19 and have a horizontal axis perpendicular to the axis of the cylinder 3. While being rotatably supported.

カムシャフト19には、吸気側開閉作動用カム25と、該
カム25の一側に隣接配置される微小作動用カム26とが一
体に設けられるとともに、吸気側開閉作動用カム25およ
び微小作動用カム26の両側に排気側開閉作動用カム27,2
7が一体に設けられる。前記微小作動用カム26は、主と
して機関の低速運転域で両吸気弁VI1,VI2の一方VI2を実
質的に休止状態とすべく基本的にはカムシャフト19を軸
線を中心とする円形の外面を有するように形成されるも
のであるが、吸気側開閉作動用カム25の高位部に対応す
る位置にはわずかに突出した突部が設けられている。し
かもカムシャフト19の軸線に沿う方向での該微小作動用
カム26の幅は比較的狭く設定される。The cam shaft 19 is integrally provided with an intake side opening / closing operation cam 25 and a minute operation cam 26 adjacent to one side of the cam 25. The intake side opening / closing operation cam 25 and the minute operation cam are also provided. Exhaust side opening / closing operation cams 27,2 on both sides of cam 26
7 are provided integrally. The micro-actuating cam 26 is basically a circle centered on the axis of the camshaft 19 so that one of the intake valves V I1 and V I2 , V I2, is substantially in a resting state mainly in the low speed operation region of the engine. Although it is formed so as to have an outer surface, a slightly protruding projection is provided at a position corresponding to the high position of the intake side opening / closing operation cam 25. Moreover, the width of the micro-actuation cam 26 in the direction along the axis of the cam shaft 19 is set to be relatively narrow.

一方の吸気弁VI1には第１吸気側ロッカアーム20が連
動、連結され、他方の吸気弁VI2には第２吸気側ロッカ
アーム21が連動、連結され、両吸気側ロッカアーム20,2
1は、カムシャフト19の斜め上方位置で該カムシャフト1
9と平行な軸線を有しながらホルダ24に固定的に支持さ
れた吸気側ロッカシャフト28で揺動自在に支承される。
また両排気側ロッカアーム22,23は、両排気弁VE1,VE2に
個別に連動、連結されており、前記カムシャフト19の斜
め上方位置で前記吸気側ロッカシャフト28と平行にして
ホルダ24に固定的に支持された排気側ロッカシャフト29
に揺動自在に支承される。The one of the intake valves V I1 is the first intake-side rocker arm 20 interlocking is connected, the other intake valve V I2 second intake-side rocker arm 21 is linked, coupled, the intake-side rocker arm 20, 2
1 is a position diagonally above the camshaft 19
An intake side rocker shaft 28 fixedly supported by a holder 24 while having an axis parallel to 9 is swingably supported.
Both exhaust side rocker arms 22 and 23 are individually interlocked and connected to both exhaust valves V E1 and V E2 , and are arranged in a holder 24 in a position diagonally above the cam shaft 19 in parallel with the intake side rocker shaft 28. Exhaust rocker shaft 29 fixedly supported
It is rockably supported by.

第１吸気側ロッカアーム20の一端には吸気側開閉作動
用カム25に隣接するローラ30が軸支され、第２吸気側ロ
ッカアーム21の一端には微小作動用カム26に摺接する摺
接部31が微小作動用カム26に対応して幅を狭くしながら
設けられる。また両排気側ロッカアーム22,23の一端に
は、排気側開閉作動用カム27,27に摺接するローラ32が
それぞれ軸支される。A roller 30 adjacent to the intake side opening / closing operation cam 25 is pivotally supported at one end of the first intake side rocker arm 20, and a sliding contact portion 31 slidingly contacting the minute operation cam 26 is provided at one end of the second intake side rocker arm 21. It is provided with a narrow width corresponding to the minute actuation cam 26. Further, rollers 32, which are in sliding contact with the exhaust side opening / closing operation cams 27, 27, are axially supported at one ends of both the exhaust side rocker arms 22, 23, respectively.

第１および第２吸気側ロッカアーム20,21の他端に
は、両吸気弁VI1,VI2の上端に当接するタペットねじ33
がそれぞれ進退自在に螺合されており、両吸気側ロッカ
アーム20,21の揺動作動に応じて各吸気弁VI1,VI2が開閉
作動することになる。また両排気側ロッカアーム22,23
の他端には、各排気弁VE1,VE2の上端に当接するタペッ
トねじ34がそれぞれ進退自在に螺合されており、両排気
側ロッカアーム22,23の揺動作動に応じて各排気弁VE1,V
E2が開閉作動することになる。The other end of each of the first and second intake-side rocker arms 20 and 21 has a tappet screw 33 that abuts the upper ends of the intake valves V I1 and V I2.
Are respectively screwed so that they can move back and forth, and the intake valves V I1 and V I2 are opened and closed according to the swinging operation of both intake side rocker arms 20 and 21. Also, both exhaust side rocker arms 22, 23
A tappet screw 34, which abuts on the upper ends of the exhaust valves V E1 and V E2 , is screwed into the other end of the exhaust valve V E1 and V E2 so as to move back and forth. V E1,, V
E2 will open and close.

両吸気側ロッカアーム20,21には、両吸気弁VI1,VI2の
作動特性を、主として機関の低速回転域と、主として機
関の高速回転域とで切換えるべく、両吸気側ロッカアー
ム20,21の連結状態、ならびに両吸気側ロッカアーム20,
21の連結解除状態を切換可能な弁作動特性切換手段35が
設けられる。The intake-side rocker arms 20 and 21 have two intake-side rocker arms 20 and 21 in order to switch the operating characteristics of the intake valves V I1 and V I2 mainly between the low-speed rotation range of the engine and the high-speed rotation range of the engine. Connected state, both intake side rocker arm 20,
A valve operating characteristic switching means 35 capable of switching the connection release state of 21 is provided.

この弁作動特性切換手段35は、両吸気側ロッカアーム
20,21を連結可能な連結ピストン36と、連結ピストン36
の移動を規制する規制部材37と、連結ピストン36および
規制部材37を連結解除側に付勢する戻しばね38とを備え
る。This valve operating characteristic switching means 35 is provided on both intake side rocker arms.
Connection piston 36 that can connect 20, 21 and connection piston 36
And a return spring 38 that urges the connecting piston 36 and the restricting member 37 toward the disconnection side.

連結ピストン36は、その一端と第１吸気側ロッカアー
ム20との間に油圧室39を画成しながら吸気側ロッカシャ
フト28と平行な軸線方向に移動可能にして第１吸気側ロ
ッカアーム20に摺動可能に嵌合される。また第１吸気側
ロッカアーム20には油圧室39に連通する連通路40が穿設
され、吸気側ロッカシャフト28内には、第１吸気側ロッ
カアーム20の揺動状態にかかわらず前記連通路40すなわ
ち油圧室39に常時連通する油路41（第１図参照）が設け
られる。而して該油路41は、第１図に示すように、連結
切換用電磁制御弁42を介して油圧源43に接続される。The connecting piston 36 is slidable on the first intake-side rocker arm 20 while defining a hydraulic chamber 39 between one end thereof and the first intake-side rocker arm 20 so as to be movable in the axial direction parallel to the intake-side rocker shaft 28. It is possible to be fitted. A communication passage 40 communicating with the hydraulic chamber 39 is formed in the first intake-side rocker arm 20, and the communication passage 40, that is, the communication passage 40, is formed in the intake-side rocker shaft 28 regardless of the swinging state of the first intake-side rocker arm 20. An oil passage 41 (see FIG. 1) that is in constant communication with the hydraulic chamber 39 is provided. As shown in FIG. 1, the oil passage 41 is connected to a hydraulic pressure source 43 via a connection switching electromagnetic control valve 42.

第２吸気側ロッカアーム21には、前記連結ピストン36
の他端に閉塞端が当接される有底円筒状の規制部材37が
摺動可能に嵌合される。また戻しばね38は第２吸気側ロ
ッカアーム21および規制部材37間に縮設されており、こ
の戻しばね38のばね力により相互に当接した前記連結ピ
ストン36および規制部材37が油圧室39側に付勢される。The connecting piston 36 is attached to the second intake-side rocker arm 21.
A closed-end cylindrical regulation member 37 whose closed end is in contact with the other end of the is fitted slidably. Further, the return spring 38 is contracted between the second intake side rocker arm 21 and the regulating member 37, and the connecting piston 36 and the regulating member 37, which are brought into contact with each other by the spring force of the return spring 38, move toward the hydraulic chamber 39 side. Be energized.

かかる弁作動特性切換手段35において、主として機関
の低速運転域では連結切換用電磁制御弁42により油圧室
39の油圧は解放されており、戻しばね38のばね力によ
り、連結ピストン36および規制部材37の当接面は第１お
よび第２吸気側ロッカアーム20,21間に対応する位置に
ある。したがって両吸気側ロッカアーム20,21は相互に
相対角変位可能な状態にあり、カムシャフト19の回転作
動により第１吸気側ロッカアーム20は吸気側開閉作動用
カム25との摺接に応じて揺動し、一方の吸気弁VI1は吸
気側カム25の形状に応じたタイミングおよびリフト量で
開閉作動する。また微小作動用カム26に摺接した第２吸
気側ロッカアーム21は実質的に休止状態となり、他方の
吸気弁VI2を実質的に休止させることができる。しかも
吸気弁VI2は完全に休止するのではなく、一方の吸気弁V
I1が開弁するときには開弁方向にわずかに作動するの
で、完全な閉弁状態を保ったときに生じる吸気弁VI2の
弁座への固着および燃料の滞留を防止することができ
る。さらに排気弁VE1,VE2は排気側開閉作動用カム27,27
の形状に応じたタイミングおよびリフト量で開閉作動す
る。In the valve operating characteristic switching means 35, the hydraulic chamber is controlled by the connection switching electromagnetic control valve 42 mainly in the low speed operation range of the engine.
The hydraulic pressure of 39 is released, and the contact surface of the connecting piston 36 and the regulating member 37 is located at a position corresponding to between the first and second intake-side rocker arms 20 and 21 due to the spring force of the return spring 38. Therefore, both intake side rocker arms 20 and 21 are in a state where they can be displaced relative to each other, and the rotation of the cam shaft 19 causes the first intake side rocker arm 20 to swing in accordance with the sliding contact with the intake side opening / closing operation cam 25. Then, one intake valve V I1 opens and closes at the timing and lift amount according to the shape of the intake cam 25. Further, the second intake-side rocker arm 21 that is in sliding contact with the minute actuation cam 26 is substantially in a resting state, and the other intake valve V I2 can be substantially resting. Moreover, the intake valve V I2 does not completely rest, but one intake valve V I2
When I1 opens, the valve slightly operates in the opening direction, so that it is possible to prevent the intake valve V I2 from sticking to the valve seat and accumulating fuel, which occurs when the valve is completely closed. Further, the exhaust valves V E1 and V E2 are connected to the exhaust side opening / closing operation cams 27 and 27.
It opens and closes at the timing and lift according to the shape of.

ところで、吸気側開閉作動用カム25による吸気弁VI1
の開弁リフト曲線C1に対して、微小作動用カム26による
吸気弁VI2の微小リフト曲線C2は、第３図（ａ）で示す
ように設定される。すなわち微小リフト曲線C2の開角中
心時期θC2は、開弁リフト曲線C1の開角中心時期θC1よ
りもクランク角に沿う遅角側に設定され、望ましくは、
微小リフト曲線C2の最大リフト部C2Mは開弁リフト曲線C
1の最大リフト部C1Mよりもクランク角に沿う遅角側に設
定される。しかも微小リフト曲線C2の終端時期θVCは、
開弁リフト曲線C1のクランク角に沿う終端の緩衝曲線部
C1S近傍に設定されている。By the way, the intake valve V I1
In contrast to the valve opening lift curve C 1 of Fig. 3, the minute lift curve C 2 of the intake valve V I2 by the cam for minute operation 26 is set as shown in Fig. 3 (a). That is, the opening angle center timing θ C2 of the minute lift curve C 2 is set on the retard side along the crank angle with respect to the opening angle center timing θ C1 of the valve opening lift curve C 1 , and desirably,
The maximum lift portion C 2M of the small lift curve C 2 is the valve opening lift curve C
It is set to the retard side along the crank angle than the first maximum lift portion C 1M. Moreover, the terminal timing θ VC of the minute lift curve C 2 is
Buffer curve section at the end along the crank angle of the valve opening lift curve C 1
It is set near C 1S .

また主として機関の高速運転時には連結切換用電磁制
御弁42に開弁し、油圧室39の高油圧を作用させる。これ
により連結ピストン36は戻しばね38のばね力に抗して油
圧室39の容積を増大する方向に移動しようとし、連結ピ
ストン36および規制部材37の軸線が一致したとき、すな
わち両吸気側ロッカアーム20,21が静止状態に入ったと
きに連結ピストン36が第２吸気側ロッカアーム21に嵌合
し、両吸気側ロッカアーム20,21が連結状態となり、吸
気側開閉作動用カム25に摺接している第１吸気側ロッカ
アーム20とともに第２吸気側ロッカアーム21が揺動し、
両吸気弁VI1,VI2は吸気側開閉作動用カム25の形状に応
じたタイミングおよびリフト量（第３図（ａ）の開弁リ
フト曲線C1で示すプロフィル）で開閉作動せしめられ
る。また両排気側ロッカアーム22,23は、低速運転域と
同様に排気側開閉作動用カム27,27の形状に応じたタイ
ミングおよびリフト量で両排気弁VE1,VE2を開閉作動せ
しめる。Further, mainly during high-speed operation of the engine, the connection switching electromagnetic control valve 42 is opened, and the high hydraulic pressure in the hydraulic chamber 39 is applied. As a result, the connecting piston 36 tries to move in the direction of increasing the volume of the hydraulic chamber 39 against the spring force of the return spring 38, and when the axes of the connecting piston 36 and the regulating member 37 coincide, that is, both intake side rocker arms 20. , 21 enters the stationary state, the connecting piston 36 fits into the second intake-side rocker arm 21, both intake-side rocker arms 20, 21 are in a connected state, and are in sliding contact with the intake-side opening / closing operation cam 25. The first intake-side rocker arm 20 swings together with the first intake-side rocker arm 20,
Both intake valves V I1 and V I2 are opened / closed at a timing and a lift amount (a profile shown by a valve opening lift curve C 1 in FIG. 3A) according to the shape of the intake side opening / closing operation cam 25. Further, both exhaust side rocker arms 22 and 23 open and close both exhaust valves V E1 and V E2 at the timing and lift amount according to the shape of the exhaust side opening / closing operation cams 27 and 27 as in the low speed operation range.

シリンダヘッド２には、両排気側ロッカアーム22,23
間で上方に向かうにつれて側方に傾斜するようにしてプ
ラグ筒部44が設けられており、このプラグ筒部44から挿
入される点火プラグ45が燃焼室５の天井面略中央部でシ
リンダヘッド２に取付けられる。The cylinder head 2 has rocker arms 22 and 23 on both exhaust sides.
A plug tube portion 44 is provided so as to incline sideways as it goes upward between them, and an ignition plug 45 inserted from this plug tube portion 44 has a cylinder head 2 at a substantially central portion of the ceiling surface of the combustion chamber 5. Mounted on.

再び第１図において、シリンダヘッド２の吸気開口端
９には、吸気マニホールド46と、スロットル弁47を有す
るスロットルボディ48とを介してエアクリーナ49が接続
される。而してエアクリーナ49から吸気開口端９までの
間で、スロットルボディ48および吸気マニホールド46内
には吸気路50が形成され、該吸気路50には、バイパス通
路51と、ファーストアイドル通路52とがスロットル弁47
を迂回して並行に接続されており、バイパス通路51には
バイパス用電磁制御弁53が介設され、ファーストアイド
ル通路52には機関本体の冷却水温に応じて作動するワッ
クス弁54が介設される。Referring again to FIG. 1, an air cleaner 49 is connected to the intake opening end 9 of the cylinder head 2 via an intake manifold 46 and a throttle body 48 having a throttle valve 47. An intake passage 50 is formed in the throttle body 48 and the intake manifold 46 between the air cleaner 49 and the intake opening end 9, and the intake passage 50 has a bypass passage 51 and a first idle passage 52. Throttle valve 47
A bypass electromagnetic control valve 53 is provided in the bypass passage 51, and a wax valve 54 that operates according to the cooling water temperature of the engine body is provided in the first idle passage 52. It

吸気マニホールド46におけるシリンダヘッド２側の端
部には、前記両吸気弁VI1,VI2に連なる吸気系、具体的
には吸気開口端９から両吸気ポート８に向けて、吸入行
程で均等に燃料を噴射すべく燃料噴射弁55が取付けら
れ、該燃料噴射弁55には燃料供給源56が接続される。At the end of the intake manifold 46 on the cylinder head 2 side, an intake system connected to the intake valves V I1 and V I2 , specifically, from the intake opening end 9 toward both intake ports 8 is evenly provided in the intake stroke. A fuel injection valve 55 is attached to inject fuel, and a fuel supply source 56 is connected to the fuel injection valve 55.

この燃料噴射弁55は、燃料供給源56から供給される燃
料を制御可能にして噴射することが可能であるとともに
噴射した燃料を微粒化するためのアシストエアを噴射可
能に構成されるものであり、アシストエアを供給するた
めの通路57が燃料噴射弁55に接続される。而して該通路
57は、各気筒に共通な空気ヘッダ58に接続されており、
この空気ヘッダ58は、電磁式空気量制御弁59およびアイ
ドル調整ねじ60を介して、スロットル弁47よりも上流側
の吸気路50に接続される。The fuel injection valve 55 is configured to be able to controllably inject the fuel supplied from the fuel supply source 56 and to inject assist air for atomizing the injected fuel. A passage 57 for supplying the assist air is connected to the fuel injection valve 55. Thus the passage
57 is connected to the air header 58 common to each cylinder,
The air header 58 is connected to the intake passage 50 on the upstream side of the throttle valve 47 via the electromagnetic air amount control valve 59 and the idle adjusting screw 60.

シリンダヘッド２の吸気開口端11には排気マニホール
ト61を介して触媒コンバータ62が接続される。A catalytic converter 62 is connected to the intake opening end 11 of the cylinder head 2 via an exhaust manifold 61.

前記連結切換用電磁制御弁42、バイパス用電磁制御弁
53、燃料噴射弁55、電磁式空気量制御弁59の作動は、コ
ンピュータから成る制御手段67により制御されるもので
あり、該制御手段67には、吸気圧力センサ64で検出され
る吸気圧力PB、機関冷却水温センサ65で検出される冷却
水温TW、ならびに回転数センサ66で検出される機関回転
数NEが入力される。Electromagnetic control valve 42 for switching the connection, electromagnetic control valve for bypass
The operations of the fuel injection valve 53, the fuel injection valve 55, and the electromagnetic air amount control valve 59 are controlled by a control means 67 composed of a computer, and the control means 67 includes an intake pressure P detected by an intake pressure sensor 64. B , the cooling water temperature T W detected by the engine cooling water temperature sensor 65, and the engine speed N E detected by the rotation speed sensor 66 are input.

而して、制御手段67は、機関が主として低速回転域に
あるときには両吸気弁VI1,VI2の一方VI2を実質的に休止
させるべく両吸気側ロッカアーム20,21を連結解除状態
とするとともに機関が主として高速回転域にあるときに
は両吸気弁VI1,VI2を吸気側開閉作動用カム25により開
閉作動せしめるべく両吸気側ロッカアーム20,21を連結
状態とするように弁作動特性切換手段35の作動を制御す
るとともに、機関が主として低速回転域にある状態すな
わち両吸気弁VI1,VI2の一方VI2が実質的に休止状態にあ
るときには燃料噴射弁55の燃料噴射時期を、第３図
（ｂ）で示すように、燃料噴射終了時期θFEが吸入行程
の前半たとえば吸入行程開始TDCから50〜90度の範囲と
なるように制御するものである。And Thus, the control unit 67, a decoupling state the intake side rocker arm 20, 21 so as to substantially pause one V I2 of the intake valves V I1, V I2 when the engine is in the low rotational speed range mainly In addition, when the engine is mainly in the high speed rotation range, the valve operating characteristic switching means is set so that both intake side rocker arms 20 and 21 are connected so that both intake valves V I1 and V I2 are opened and closed by the intake side opening and closing operation cam 25. While controlling the operation of 35, when the engine is mainly in the low speed rotation range, that is, when one of the intake valves V I1 and V I2 , V I2, is substantially in the idle state, the fuel injection timing of the fuel injection valve 55 is set to As shown in FIG. 3B, the fuel injection end timing θ FE is controlled so as to fall within the range of 50 to 90 degrees from the first half of the intake stroke, for example, the intake stroke start TDC.

次にこの実施例の作用について説明すると、機関が主
として高速回転域にあるときには、制御手段67は弁作動
特性切換手段35により両吸気側ロッカアーム20,21を連
結状態とし、動弁装置18は両吸気弁VI1,VI2を吸気側開
閉作動用カム25で定まるタイミングおよびリフト量で開
閉作動させる。Next, the operation of this embodiment will be described. When the engine is mainly in the high speed rotation range, the control means 67 connects both intake side rocker arms 20, 21 by the valve operating characteristic switching means 35, and the valve operating device 18 operates both The intake valves V I1 and V I2 are opened / closed at the timing and lift determined by the intake side opening / closing cam 25.

また機関が主として低速回転域にあるときには、制御
手段67により弁作動特性切換手段35は両吸気側ロッカア
ーム20,21の連結を解除する状態に切換作動せしめられ
る。これにより、両吸気弁VI1,VI2のうちの一方VVI2は
実質的に休止状態となり、他方の吸気弁VI1のみが吸気
側開閉作動用カム25で定まるタイミングおよびリフト量
で開閉作動せしめられる。Further, when the engine is mainly in the low speed rotation range, the valve operating characteristic switching means 35 is switched by the control means 67 to a state where the connection between the intake side rocker arms 20 and 21 is released. Thus, one VV I2 of the intake valves V I1, V I2 is substantially become dormant, only the other intake valve V I1 is made to opened and closed with a timing and a lift amount determined by the intake-side opening and closing cam 25 To be

これにより燃焼室５内には、実質的には両吸気弁口６
の一方のみから混合気が流入することになり、燃焼室５
内にスワールが形成されることになる。しかも該スワー
ル生成時の燃料噴射弁55による燃料噴射終了時期θFEは
第３図（ｂ）で示すように、吸入行程の前半望ましくは
吸入行程開始TDCから50〜90度の範囲に設定されるもの
であり、噴射燃料を開閉作動している吸気弁VI1に対応
する吸気弁口６から燃料室５内に順次導入して軸方向層
状給気を達成することが可能となり、本発明者の実験結
果を示す第４図のように、燃焼性を向上することが可能
となるとともに、本発明者の実験結果を示す第５図のよ
うに、トルク変動率を小さく抑えることができる。As a result, in the combustion chamber 5, substantially both intake valve ports 6
The air-fuel mixture will flow in from only one side of the combustion chamber 5
A swirl will be formed inside. Moreover, as shown in FIG. 3B, the fuel injection end timing θ FE by the fuel injection valve 55 at the time of the swirl generation is set in the first half of the intake stroke, preferably in the range of 50 to 90 degrees from the intake stroke start TDC. Therefore, it becomes possible to introduce the injected fuel into the fuel chamber 5 sequentially from the intake valve port 6 corresponding to the intake valve V I1 which is opening and closing, and achieve the axial stratified charge. Combustibility can be improved as shown in FIG. 4 showing the experimental result, and the torque fluctuation rate can be suppressed to be small as shown in FIG. 5 showing the experimental result of the present inventor.

さらに微小作動用カム26によりわずかに開弁される吸
気弁VI2の開角中心時期θC2は、第３図（ａ）で示すよ
うに、吸入行程にあって後半側望ましくは吸入行程開始
TDCから130〜180度の範囲に設定されており、しかも微
小リフト曲線C2の最大リフト部C2Mは開弁リフト曲線C1
の最大リフト部C1Mよりもクランク角に沿う遅角側に設
定されている。そのように設定すると、吸気弁VI2のわ
ずかな開弁に伴うスワールの乱れ発生を抑制することが
可能となる。而して開角中心時期θC2に対する燃焼限界
を実験結果と示すと第６図のようになり、開角中心時期
θC2を吸入行程にあって後半側望ましくは吸入行程開始
TDCから130〜180度の範囲に設定すると、希薄燃焼限界
が向上することが明らかである。また開角中心時期θC2
の相違によるトルク変動、燃費および排ガス性状に及ぼ
す影響について本発明者が実験した結果を示すと第７図
のようになり、前記開角中心時期θC2を吸入行程の中央
部に設定したときを破線で示す曲線としたときに、開角
中心時期θC2を吸入行程の後半に設定したときには実線
で示す曲線のようになり、トルク変動率および燃費を低
く抑えることができるとともに排ガス性状を良好にする
ことができる。Further, as shown in FIG. 3 (a), the opening angle center timing θ C2 of the intake valve V I2 which is slightly opened by the minute actuation cam 26 is in the intake stroke and is preferably in the latter half of the intake stroke.
It is set in the range of 130 to 180 degrees from TDC, and the maximum lift portion C 2M of the minute lift curve C 2 is the valve opening lift curve C 1
It is set on the retard side along the crank angle with respect to the maximum lift section C 1M . With such a setting, it becomes possible to suppress the occurrence of swirl turbulence due to the slight opening of the intake valve V I2 . Fig. 6 shows the combustion limit for the open angle center timing θ C2 as an experimental result. The open angle center timing θ C2 is in the intake stroke, and the latter half of the intake stroke is desirable.
It is clear that the lean burn limit is improved by setting the range from 130 to 180 degrees from TDC. Also, the center angle of opening angle θ C2
Fig. 7 shows the results of experiments conducted by the present inventor regarding the influence of the difference on the torque fluctuation, fuel consumption and exhaust gas properties. The results obtained when the opening angle central timing θ C2 is set at the center of the intake stroke are shown in Fig. 7. When the open-angle center timing θ C2 is set to the latter half of the intake stroke when the curve is shown by the broken line, it becomes the curve shown by the solid line, which makes it possible to suppress the torque fluctuation rate and fuel consumption to a low level and to improve the exhaust gas properties. can do.

かかる内熱機関においてピストン４の燃焼室５に臨む
上面には凹部4aが設けられており、その凹部4aにより燃
焼室５のコンパクト化が可能となる。また動弁装置18は
両吸気弁VI1,VI2および面排気弁VE1,VE2に対して共通な
単一のカムシャフト19を備えるものであり、燃焼室５の
天井面略中央部には点火プラグ45が配設されるので、シ
リンダ３の軸線を含む平面への投影図上で両吸気弁VI1,
VI2が両排気弁VE1,VE2の軸線がなす角度を狭くすること
が可能であり、これによっても燃焼室５のコンパクト化
が可能である。このような燃焼室５のコンパクト化によ
り、燃焼室５内で生じるスワール速度を増大し、燃焼性
をより向上させることができる。In such an internal heat engine, a recess 4a is provided on the upper surface of the piston 4 facing the combustion chamber 5, and the recess 4a enables the combustion chamber 5 to be made compact. Further, the valve gear 18 is provided with a single camshaft 19 which is common to both the intake valves V I1 , V I2 and the surface exhaust valves V E1 , V E2 , and is provided at a substantially central portion of the ceiling surface of the combustion chamber 5. Is provided with a spark plug 45, so that both intake valves V I1 ,
It is possible to narrow the angle formed by the axes of the two exhaust valves V E1 and V E2 by V I2 , which also allows the combustion chamber 5 to be made compact. By making the combustion chamber 5 compact in this way, the swirl speed generated in the combustion chamber 5 can be increased and the combustibility can be further improved.

さらに燃焼噴射弁55におけるアシストエアにより噴射
燃料の微粒化を図ると、希薄燃焼性がより一層向上す
る。Further, when the injected fuel is atomized by the assist air in the combustion injection valve 55, the lean burnability is further improved.

また吸気弁VI2をわずかに開いて実質休止状態とする
ことにより、吸気弁VI2に対応する吸気ポート８内に燃
料噴射弁55から噴射される燃料が滞留することを防止
し、空燃比の変動が生じることを回避することが可能と
なる。Further, by slightly opening the intake valve V I2 to bring it into a substantially resting state, the fuel injected from the fuel injection valve 55 is prevented from staying in the intake port 8 corresponding to the intake valve V I2 , and the air-fuel ratio It is possible to avoid fluctuations.

ところで、主として低速回転域にある状態から主とし
て高速回転域にある状態へと機関の運転領域が変化する
際に、弁作動特性切換手段35により両吸気側ロッカアー
ム20,21を連結解除状態から連結状態へと切換えるとき
に、弁作動特性切換手段35の連結ピストン36がわずかに
第２吸気側ロッカアーム21内に嵌合した状態で、吸気側
カム25による第１吸気側ロッカアーム20の叩かれによ
り、前記嵌合状態が外れて切換が失敗することがある。
而して、その切換失敗が吸気弁VI1の開弁方向作動途中
に生じたときには、第２吸気側ロッカアーム21は第１吸
気側ロッカアーム20とともに開弁方向に揺動作動してい
る途中に第１吸気側ロッカアーム20との連結が解除され
ることになり、吸気弁VI2は開弁作動途中から弁ばね14
により閉弁方向に反転作動することになり、その閉弁方
向への反転作動が比較的高いリフト位置で生じたときに
は吸気弁VI2が弁座に衝撃的に着座するおそれがある。
しかるに、第２吸気側ロッカアーム21に対応してカムシ
ャフト19には微小作動用カム26が設けられており、その
微小作動用カム26によりわずかに開弁される吸気弁VI2
の開角中心時期θC2が吸入行程の後半側であってしかも
閉弁時期θVCが吸気側開閉作動用カム25による吸気弁V
I1の開弁リフト曲線C1の緩衝曲線部C1S近傍に対応する
時期に設定されている。すなわち吸気弁VI1が比較的高
い位置までリフトした後の吸入行程では、第１および第
２吸気側ロッカアーム20,21の連結が解除されると、第
２吸気側ロッカアーム21および吸気弁VI2の作動は微小
作動用カム26で規制されることになる。このため、弁作
動特性切換手段35による低速回転域から高速回転域への
切換失敗により吸気弁VI2が比較的高いリフト位置から
閉弁方向に反転作動しても、第２吸気側ロッカアーム21
の閉弁方向作動が微小作動用カム26で規制されることに
より、吸気弁VI2が衝撃的に着座することが回避され、
衝撃音の発生を防止することができる。By the way, when the operating region of the engine changes from a state mainly in the low speed rotation range to a state mainly in the high speed rotation range, the valve actuation characteristic switching means 35 causes both intake side rocker arms 20, 21 to be in the connection state from the connection release state to the connection state. At the time of switching to, the connection piston 36 of the valve operating characteristic switching means 35 is slightly fitted into the second intake side rocker arm 21, and the first intake side rocker arm 20 is hit by the intake side cam 25, so that The mated state may be lost and the switching may fail.
Thus, when the switching failure occurs during the operation of the intake valve V I1 in the valve opening direction, the second intake side rocker arm 21 moves together with the first intake side rocker arm 20 while swinging in the valve opening direction. 1 The connection with the rocker arm 20 on the intake side is released, and the intake valve V I2 opens the valve spring 14 during the opening operation.
This causes reversal operation in the valve closing direction, and when the reversal operation in the valve closing direction occurs at a relatively high lift position, the intake valve V I2 may be impacted and seated on the valve seat.
However, the camshaft 19 is provided with a minute actuation cam 26 corresponding to the second intake-side rocker arm 21, and the intake valve V I2 is slightly opened by the minute actuation cam 26.
The opening angle center timing θ C2 is in the latter half of the intake stroke and the valve closing timing θ VC is the intake valve opening / closing operation cam 25 intake valve V
It is set at a time corresponding to the vicinity of the buffer curve portion C 1S of the valve opening lift curve C 1 of I1 . That is, in the intake stroke after the intake valve V I1 has been lifted to a relatively high position, when the first and second intake side rocker arms 20, 21 are disconnected, the second intake side rocker arm 21 and the intake valve V I2 The operation is regulated by the minute operation cam 26. Therefore, even if the intake valve V I2 reverses from the relatively high lift position to the valve closing direction due to the failure of the valve operation characteristic switching means 35 to switch from the low speed rotation range to the high speed rotation range, the second intake side rocker arm 21
By restricting the valve closing direction operation of the intake valve by the minute operation cam 26, it is possible to prevent the intake valve V I2 from being seated by shock,
It is possible to prevent the generation of impact noise.

また機関が主として低速回転域にあるときには、制御
手段67により弁作動特性切換手段35は両吸気側ロッカア
ーム20,21の連結を解除する状態に切換作動せしめられ
る。これにより、両吸気弁VI1,VI2のうちの一方VI2は実
質的に休止状態となり、他方の吸気弁VI1のみが吸気側
カム25で定まるタイミングおよびリフト量で開閉作動せ
しめられる。Further, when the engine is mainly in the low speed rotation range, the valve operating characteristic switching means 35 is switched by the control means 67 to a state where the connection between the intake side rocker arms 20 and 21 is released. Thus, one V I2 of the intake valves V I1, V I2 is substantially become dormant, only the other intake valve V I1 is made to opened and closed with a timing and a lift amount determined by the intake cam 25.

第８図、第９図および第10図は本発明の他の実施例を
示すものであり、上述の実施例に対応する部分には同一
の参照符号を付す。FIG. 8, FIG. 9 and FIG. 10 show another embodiment of the present invention, and the portions corresponding to the above-mentioned embodiment are designated by the same reference numerals.

この動弁装置18′は、カムシャフト19′と、カムシャ
フト19′の回転運動を両吸気弁VI1,VI2の開閉運動に変
換するための弁駆動部材としての第１、第２および第３
吸気側ロッカアーム71,72,73と、前記カムシャフト19′
の回転運動を両排気弁VE1,VE2の開閉運動に変換するた
めの第１および第２排気側ロッカアーム22,23とを備え
る。This valve operating device 18 'includes a cam shaft 19', and first, second, and first valve drive members for converting rotational movements of the cam shaft 19 'into opening / closing movements of both intake valves V I1 , V I2 . Three
The intake side rocker arms 71, 72, 73 and the camshaft 19 '
And the first and second exhaust side rocker arms 22 and 23 for converting the rotational movement of the above into the opening and closing movements of both exhaust valves V E1 and V E2 .

カムシャフト19′には、機関の低速運転に対応した形
状の第１吸気側開閉作動用カム74と、機関の高速運転に
対応した形状に形成されながら第１吸気側開閉作動用カ
ム74の一側に隣接配置される第２吸気側開閉作動用カム
75と、第２吸気側開閉作動用カム75の一側に隣接する微
小作動用カム76とが一体に設けられるとともに、第１吸
気側開閉作動用カム74および微小作動用カム76の両側に
排気側開閉作動用カム27,27が一体に設けられる。The camshaft 19 'includes a first intake side opening / closing operation cam 74 having a shape corresponding to the low speed operation of the engine and a first intake side opening / closing operation cam 74 having a shape corresponding to the high speed operation of the engine. Second intake side opening / closing operation cam adjacent to the side
75 and a minute operation cam 76 adjacent to one side of the second intake side opening / closing operation cam 75 are integrally provided, and exhaust is provided on both sides of the first intake side opening / closing operation cam 74 and the minute operation cam 76. Side opening / closing operation cams 27, 27 are integrally provided.

一方の吸気弁VI1には第１吸気側ロッカアーム71が連
動、連結され、他方の吸気弁VI2には第３吸気側ロッカ
アーム73が連動、連結され、両吸気弁VI1,VI2に対して
自由となり得る第２吸気側ロッカアーム72が第１および
第３吸気側ロッカアーム71,73間に配置される。而して
各吸気側ロッカアーム71〜73は吸気側ロッカシャフト28
で揺動自在に支承される。また両排気弁VE1,VE2に個別
に連動、連結された第１および第２排気側ロッカアーム
22,23は排気側ロッカシャフト29に揺動自在に支承され
る。The one of the intake valves V I1 interlocked first intake-side rocker arm 71, is connected, the third intake-side rocker arm 73 is linked, is coupled to the other intake valve V I2, with respect to the intake valves V I1, V I2 A second intake-side rocker arm 72, which can be free, is arranged between the first and third intake-side rocker arms 71, 73. Thus, the intake-side rocker arms 71 to 73 are the intake-side rocker shafts 28.
It is rockably supported by. In addition, the first and second exhaust side rocker arms that are individually interlocked and connected to both exhaust valves V E1 and V E2
22 and 23 are swingably supported on the exhaust side rocker shaft 29.

第１吸気側ロッカアーム71の一端は第１吸気側開閉作
動用カム74に摺接され、第３吸気側ロッカアーム73の一
端は微小作動用カム76に摺接され、第２吸気側ロッカア
ーム72は第２吸気側開閉作動用カム75に摺接される。ま
た両排気側ロッカアーム22,23の一端は排気側開閉作動
用カム27,27にそれぞれ摺接される。One end of the first intake side rocker arm 71 is in sliding contact with the first intake side opening / closing operation cam 74, one end of the third intake side rocker arm 73 is in sliding contact with the minute operation cam 76, and the second intake side rocker arm 72 is 2 Sliding contact with the intake side opening / closing operation cam 75. Further, one ends of both the exhaust side rocker arms 22 and 23 are in sliding contact with the exhaust side opening / closing operation cams 27 and 27, respectively.

ところで、ホルダ24の上端には支持板78が固設されて
おり、この支持板78には、第２吸気側ロッカアーム72を
カムシャフト19′の第２吸気側開閉作動用カム75に摺接
させる方向に弾発付勢するロストモーション機構79が配
設される。By the way, a support plate 78 is fixedly provided on the upper end of the holder 24, and the second intake side rocker arm 72 is slidably brought into contact with the second intake side opening / closing operation cam 75 of the cam shaft 19 '. A lost motion mechanism 79 that elastically urges in the direction is provided.

各吸気側ロッカアーム71〜73には弁作動特性切換手段
35′が設けられており、この弁作動特性切換手段35′
は、第１吸気側ロッカアーム71および第２吸気側ロッカ
アーム72を連結可能な連結ピストン82と、第２吸気側ロ
ッカアーム72および第３吸気側ロッカアーム73を連結可
能な連結ピン83と、連結ピストン82および連結 ピン83の移動を規制する規制部材84と、連結ピストン8
2、連結ピン83および規制部材84を連結解除側に付勢す
る戻しばね85とを備える。Each intake side rocker arm 71-73 has a valve operating characteristic switching means.
35 'is provided, and this valve operating characteristic switching means 35' is provided.
Is a connecting piston 82 capable of connecting the first intake-side rocker arm 71 and the second intake-side rocker arm 72, a connecting pin 83 capable of connecting the second intake-side rocker arm 72 and the third intake-side rocker arm 73, a connecting piston 82, The regulating member 84 for regulating the movement of the connecting pin 83 and the connecting piston 8
2. A return spring 85 for urging the connecting pin 83 and the regulating member 84 toward the connection release side.

連結ピストン82は、吸気側ロッカシャフト28と平行な
軸線方向に移動可能として第１吸気側ロッカアーム71に
摺動可能に嵌合され、該連結ピストン82の一端と第１吸
気側ロッカアーム71との間には、吸気側ロッカシャフト
28内の油路41に通じる油圧室86が画成される。第２吸気
側ロッカアーム72には、前記連結ピストン82の他端に一
端が当接される連結ピン83が吸気側ロッカシャフト28と
平行な軸線方向に摺動可能に嵌合される。さらに第３吸
気側ロッカアーム73には、連結ピン83の他端に当接する
有底円筒状の規制部材84が吸気側ロッカシャフト28と平
行な軸線方向に摺動可能に嵌合されており、戻しばね85
は、規制部材84および第３吸気側ロッカアーム73間に縮
設される。The connecting piston 82 is slidably fitted to the first intake-side rocker arm 71 so as to be movable in the axial direction parallel to the intake-side rocker shaft 28, and is disposed between one end of the connecting piston 82 and the first intake-side rocker arm 71. On the intake side rocker shaft
A hydraulic chamber 86 communicating with the oil passage 41 in 28 is defined. A connecting pin 83, one end of which abuts against the other end of the connecting piston 82, is fitted to the second intake-side rocker arm 72 so as to be slidable in the axial direction parallel to the intake-side rocker shaft 28. Further, a cylindrical bottomed cylindrical regulating member 84 that abuts the other end of the connecting pin 83 is fitted to the third intake side rocker arm 73 so as to be slidable in the axial direction parallel to the intake side rocker shaft 28, and then returned. Spring 85
Is contracted between the restricting member 84 and the third intake-side rocker arm 73.

かかる弁作動特性切換手段35′では、主として機関の
低速回転域で油圧室86の油圧を解放すると、戻しばね85
のばね力により、連結ピストン82および連結ピン83の当
接面は第１吸気側ロッカアーム71および第２吸気側ロッ
カアーム72間に対応する位置にあり，連結ピン83および
規制部材84の当接面は第２吸気側ロッカアーム72および
第３吸気側ロッカアーム72間に対応する位置にある。し
たがって各ロッカアーム71〜73は相互に相対角変位可能
な状態にあり、カムシャフト19′の回転作動により第１
吸気側ロッカアーム71は第１吸気側開閉作動用カム74と
の摺接に応じて揺動し、一方の吸気弁VI1は第１吸気側
開閉作動用カム74の形状に応じたタイミングおよびリフ
ト量で開閉作動する。また微小作動用カム76に摺接した
第３吸気側ロッカアーム73は実質的に休止状態となり、
他方の吸気弁VI2を実質的に休止させることができる。
さらに第２吸気側ロッカアーム72は第２吸気側開閉作動
用カム75との摺接に応じて揺動するが、その揺動動作は
第１および第３吸気側ロッカアーム71,73に何らの影響
も及ぼさない。また排気弁VE1,VE2は排気側開閉作動用
カム27,27の形状に応じたタイミングおよびリフト量で
開閉作動する。In the valve operating characteristic switching means 35 ', when the hydraulic pressure in the hydraulic chamber 86 is released mainly in the low speed rotation range of the engine, the return spring 85
Due to the spring force of the connecting piston 82 and the connecting pin 83, the contact surfaces of the connecting pin 82 and the regulating member 84 are in contact with each other between the first intake side rocker arm 71 and the second intake side rocker arm 72. It is located at a position corresponding to between the second intake-side rocker arm 72 and the third intake-side rocker arm 72. Therefore, the rocker arms 71 to 73 are in a state of being capable of relative angular displacement with respect to each other, and the first rotation of the camshaft 19 'causes
The intake-side rocker arm 71 swings in response to the sliding contact with the first intake-side opening / closing operation cam 74, and one intake valve V I1 has the timing and lift amount according to the shape of the first intake-side opening / closing operation cam 74. Open and close with. Further, the third intake-side rocker arm 73 which is in sliding contact with the minute actuation cam 76 is substantially in a rest state,
The other intake valve V I2 can be substantially deactivated.
Further, the second intake side rocker arm 72 swings in response to the sliding contact with the second intake side opening / closing operation cam 75, but the swinging operation has no influence on the first and third intake side rocker arms 71, 73. Does not reach. Further, the exhaust valves V E1 and V E2 are opened / closed at timings and lift amounts according to the shapes of the exhaust side opening / closing actuating cams 27, 27.

ところで、微小作動用カム76による吸気弁VI2の微小
リフト曲線C2における開角中心時期θC2は、第10図に示
すように、第１吸気側開閉作動用カム74による吸気弁V
I1の開弁リフト曲線C1′における開角中心時期θC1′よ
りもクランク角に沿う遅角側の吸入行程、望ましくは吸
入行程開始TDCから130〜180度の範囲に設定されてい
る。しかも微小作動用カム76によりわずかに開弁される
吸気弁VI2の閉弁時期θVCは、第１吸気側開閉作動用カ
ム74による吸気弁VI1の開弁リフト曲線C1′におけるク
ランク角に沿う終端部の緩衝曲線部C1S′に対応する部
分に設定されるものである。By the way, as shown in FIG. 10, the opening angle center timing θ C2 of the minute lift curve C 2 of the intake valve V I2 by the minute operation cam 76 is determined by the intake valve V I by the first intake side opening / closing operation cam 74.
The intake stroke on the retard side along the crank angle with respect to the opening angle central timing θ C1 ′ in the valve opening lift curve C 1 ′ of I1 is set, preferably in the range of 130 to 180 degrees from the intake stroke start TDC. Moreover, the closing timing θ VC of the intake valve V I2 slightly opened by the minute actuation cam 76 is determined by the crank angle in the valve opening lift curve C 1 ′ of the intake valve V I1 by the first intake side opening / closing actuation cam 74. It is set at a portion corresponding to the buffer curve portion C 1S ′ at the end portion along the line.

主として機関の高速回転域で油圧室86に高油圧を作用
させると、連結ピストン82は連結ピン83を押圧しながら
戻しばね85のばね力に抗して油圧室86の容積を増大する
方向に移動しようとし、連結ピストン82、連結ピン83お
よび規制部材84の軸線が一致したとき、すなわち各吸気
側ロッカアーム71〜73が静止状態に入ったときに連結ピ
ストン82が第２吸気側ロッカアーム72に嵌合し、それに
応じて連結ピン33が第吸気側ロッカアーム73に嵌合する
ことにより、各吸気側ロッカアーム71〜73が連結状態と
なる。したがって第２吸気側開閉作動用カム75に摺接し
ている第２吸気側ロッカアーム72とともに第１および第
３吸気側ロッカアーム71,73が揺動し、両吸気弁VI1,VI2
は第２吸気側開閉作動用カム75の形状に応じたタイミン
グおよびリフト量で、第10図の開弁リフト曲線C3で示す
ように開閉作動せしめられる。また両排気側ロッカアー
ム22,23は、低速運転域と同様に排気側開閉作動用カム2
7,27の形状に応じたタイミングおよびリフト量で両排気
弁VE1,VE2を開閉作動せしめる。When a high hydraulic pressure is applied to the hydraulic chamber 86 mainly in the high-speed rotation range of the engine, the connecting piston 82 moves in a direction of increasing the volume of the hydraulic chamber 86 against the spring force of the return spring 85 while pressing the connecting pin 83. When the axes of the connecting piston 82, the connecting pin 83, and the regulating member 84 are aligned with each other, that is, when the intake-side rocker arms 71 to 73 enter the stationary state, the connecting piston 82 is fitted to the second intake-side rocker arm 72. Then, the connecting pin 33 is fitted into the first intake-side rocker arm 73 accordingly, whereby the intake-side rocker arms 71 to 73 are brought into a connected state. Therefore, the first and third intake-side rocker arms 71 and 73 swing together with the second intake-side rocker arm 72 that is in sliding contact with the second intake-side opening / closing operation cam 75, and both intake valves V I1 and V I2
Is a timing and a lift amount according to the shape of the second intake side opening / closing operation cam 75, and is opened / closed as shown by the valve opening lift curve C 3 in FIG. Both exhaust side rocker arms 22 and 23 are connected to the exhaust side opening / closing operation cam 2 as in the low speed operation range.
Both exhaust valves V E1 and V E2 are opened and closed at the timing and lift amount according to the shape of 7,27.

このような動弁装置18′を備える内燃機関において
も、第１図ないし第７図で示した実施例と同様の制御を
行なうことにより、上記実施例と同様の効果を奏するこ
とができる。Even in an internal combustion engine equipped with such a valve operating device 18 ', the same effects as those of the above-described embodiment can be obtained by performing the same control as that of the embodiment shown in FIGS. 1 to 7.

C.発明の効果 以上のように各請求項の発明によれば、主として機関
の低速運転域における吸入行程では、開閉作動用カムに
より開閉駆動される一方の吸気弁よりも遅れて微小カム
により地方の吸気弁を僅かに開くようにしたので、該地
方の吸気弁の、実質休止状態となるような僅かな開き動
作がスワール生成に与える悪影響を排除して燃焼性を向
上することができ、しかも弁作動特性切換手段による弁
作動特性切換が失敗して他方の吸気弁が比較的高リフト
まで開弁方向に作動した後に閉弁方向に反転作動して
も、微小作動用カムの規制により吸気弁が弁座に直接衝
突することを回避して衝撃音の発生を効果的に防止でき
る。C. Effects of the Invention As described above, according to the inventions of the claims, in the intake stroke mainly in the low-speed operation range of the engine, the minute cam is used to delay the local movement of the intake valve which is opened and closed by the opening / closing operation cam. Since the intake valve is slightly opened, the adverse effect of swirl generation caused by a slight opening operation of the local intake valve on the swirl generation can be eliminated and the combustibility can be improved. Even if the valve operation characteristic switching means fails to switch the valve operation characteristic and the other intake valve operates in the valve opening direction up to a relatively high lift and then reverses in the valve closing direction, the intake valve is controlled by the minute operation cam. It is possible to effectively prevent the impact sound from being generated by avoiding the direct collision with the valve seat.

その上、燃料噴射終了時期を、前記他方の吸気弁が殆
ど開かれていない吸入行程の前半に設定したので、該他
方の吸気弁を上記のように僅かに開き動作させるにも係
わらず良好な層状給気が達成され、トルク変動を抑える
ことが可能となる。Moreover, since the fuel injection end timing is set to the first half of the intake stroke in which the other intake valve is almost not opened, the other intake valve is operated in a favorable manner in spite of the slight opening operation as described above. Stratified air supply is achieved, and torque fluctuations can be suppressed.

また請求項２の発明によれば、微小作動用カムによる
微小リフト曲線の最大リフト部を開閉作動用カムによる
開弁リフト曲線の最大リフト部よりもクランク角に沿う
後方側に設定することにより、他方の吸気弁が僅かに開
いたときのスワール生成阻害をより有効に回避すること
が可能となる。Further, according to the invention of claim 2, the maximum lift portion of the minute lift curve by the cam for minute operation is set to the rear side along the crank angle with respect to the maximum lift portion of the valve lift curve by the cam for opening / closing operation. It becomes possible to more effectively avoid the swirl generation inhibition when the other intake valve is slightly opened.

【図面の簡単な説明】[Brief description of drawings]

第１図ないし第７図は本発明の一実施例を示すものであ
り、第１図は全体構成図、第２図は第１図のII−II線に
沿う部分切欠き拡大平面図、第３図は吸気弁作動状態と
燃料噴射時期との関係を示す図、第４図は燃料噴射時期
の燃焼安定性に及ぼす影響の実験結果を示すグラフ、第
５図は燃料噴射終了時期のトルク変動率に及ぼす影響を
実験結果を示すグラフ、第６図は実質休止状態にある吸
気弁の開角中心時期の相違による燃焼限界に及ぼす影響
の実験結果を示すグラフ、第７図は実質休止状態にある
吸気弁の開角中心時期の相違によるトルク変動率、燃費
および排ガス性状に及ぼす影響の実験結果を示すグラ
フ、第８図ないし第10図は本発明の他の実施例を示すも
のであり、第８図は動弁装置の縦断面図であって第９図
のVIII−VIII線断面図、第９図は第８図のIX−IX線断面
図、第10図は吸気弁作動状態と燃料噴射時期との関係を
示す図である。 18,18′……動弁装置、19,19′……カムシャフト、20,2
1;71,72,73……弁駆動部材としての吸気側ロッカアー
ム、25,74,75……開閉作動用カム、26,76……微小作動
用カム、35,35′……弁作動特性切換手段、55……燃料
噴射弁、 C1,C1′……開弁リフト曲線、C1M,C2M……最大リフト
部、C1S,C1S′……緩衝曲線部、C2……微小リフト曲
線、VI1,VI2……吸気弁、θC1,θC1′，θC2……開角中
心時期、θFE……燃料噴射終了時期、θVC……終端時期1 to 7 show an embodiment of the present invention. FIG. 1 is an overall configuration diagram, FIG. 2 is an enlarged plan view of a partial notch along line II-II of FIG. FIG. 3 is a diagram showing the relationship between the intake valve operating state and the fuel injection timing, FIG. 4 is a graph showing the experimental results of the influence of the fuel injection timing on the combustion stability, and FIG. 5 is the torque fluctuation at the fuel injection end timing. Fig. 6 is a graph showing the experimental result of the effect on the combustion rate, Fig. 6 is a graph showing the experimental result of the effect on the combustion limit due to the difference in the opening angle center timing of the intake valve in the substantially resting state, and Fig. 7 is the substantially resting state. FIG. 8 to FIG. 10 are graphs showing the experimental results of the influences on the torque fluctuation rate, the fuel consumption, and the exhaust gas properties due to the difference in the opening center timing of a certain intake valve, and FIGS. 8 to 10 show another embodiment of the present invention. FIG. 8 is a vertical cross-sectional view of the valve gear, which is a cross-sectional view taken along the line VIII-VIII in FIG. Figure 9 sectional view taken along line IX-IX of Figure 8, Figure 10 is a diagram showing the relationship between the intake valve operating state and the fuel injection timing. 18,18 ′ …… Valve operating device, 19,19 ′ …… Camshaft, 20,2
1; 71,72,73 …… Intake side rocker arm as valve drive member, 25,74,75 …… Cam for opening / closing operation, 26,76 …… Cam for minute operation, 35,35 ′ …… Switching valve operation characteristics means, 55 ...... fuel injection valve, C 1, C 1 '...... opening lift curve, C 1M, C 2M ...... maximum lift unit, C 1S, C 1S' ...... buffer curve portion, C 2 ...... minute Lift curve, V I1 , V I2 …… Intake valve, θ C1 , θ C1 ′, θ C2 …… Open angle center timing, θ FE …… Fuel injection end timing, θ VC …… End timing

───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.6 識別記号 庁内整理番号 ＦＩ 技術表示箇所 Ｆ０２Ｄ 41/34 Ｆ 9247−3Ｇ (56)参考文献 特開 昭63−124817（ＪＰ，Ａ) 特開 昭62−288305（ＪＰ，Ａ) 特開 昭64−80735（ＪＰ，Ａ)─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 6 Identification number Internal reference number FI Technical indication location F02D 41/34 F 9247-3G (56) References JP-A-63-124817 (JP, A) Special features Kai 62-288305 (JP, A) JP 64-80735 (JP, A)

Claims (3)

【特許請求の範囲】[Claims] 【請求項１】主として機関の低速運転域での吸入行程で
一対の吸気弁（VI1,V12）のうち一方の吸気弁（VI1）を
開閉駆動するための開閉作動用カム（25,74）、ならび
に他方の吸気弁（VI2）を実質的な休止状態とする程度
の微小量だけ開くための微小作動用カム（26,76）を含
む複数のカム（25,26;74,75,76）が設けられたカムシャ
フト（19,19′）を備える動弁装置（18,18′）には、両
吸気弁（VI1,VI2）の作動特性を機関の運転状態に応じ
て切換可能な弁作動特性切換手段（35,35′）が設けら
れ、前記一対の吸気弁（VI1,VI2）に連なる吸気系に対
し吸入行程で燃料噴射を行う燃料噴射弁（55）を備えて
なる、内燃機関において、 前記微小作動用カム（26,76）は、主として機関の低速
運転域での開閉作動用カム（25,74）による一方の吸気
弁（VI1）の開弁リフト曲線（C1,C1′）の開角中心時期
（θC1,θC1′）よりも遅角側に開角中心時期（θC2）
を有するとともに前記開弁リフト曲線（C1,C1′）のク
ランク角に沿う終端の緩衝曲線部（C1S,C1S′）近傍に
終端時期（θVC）を有する微小リフト曲線（C2）で他方
の吸気弁（VI2）を開くべく形成され、実質的に前記一
方の吸気弁（VI1）のみが開閉作動している運転状態で
の前記燃料噴射弁（55）の燃料噴射終了時期（θEF）が
吸入行程前半に設定されることを特徴とする内燃機関。Claims: 1. An opening / closing actuating cam (25, 25) for opening and closing one intake valve (V I1 ) of a pair of intake valves (V I1 , V 12 ) mainly in an intake stroke in a low speed operation range of an engine. 74), as well as a plurality of cams (25,26; 74,75) including a micro-actuating cam (26,76) for opening the other intake valve (V I2 ) by a minute amount to put it into a substantially resting state. , 76) provided with a camshaft (19, 19 '), the operating characteristics of both intake valves (V I1 , V I2 ) depend on the operating condition of the engine. A switchable valve operating characteristic switching means (35, 35 ') is provided, and a fuel injection valve (55) for injecting fuel in an intake stroke to an intake system connected to the pair of intake valves (V I1 , V I2 ) is provided. In the internal combustion engine, the minute actuation cams (26, 76) are used to open and close one intake valve (V I1 ) mainly by the opening / closing actuation cams (25, 74) in the low speed operation range of the engine. Open angle center timing (θ C2 ) on the retard side of the lift curve (C 1 , C 1 ′) open angle central timing (θ C1 , θ C1 ′)
And a minute lift curve (C 2 ) having an end time (θ VC ) in the vicinity of a buffer curve part (C 1S , C 1S ′) at the end along the crank angle of the valve opening lift curve (C 1 , C 1 ′). ) Is formed to open the other intake valve (V I2 ), and the fuel injection of the fuel injection valve (55) is completed in the operating state in which only the one intake valve (V I1 ) is substantially opened and closed. An internal combustion engine characterized in that the timing (θ EF ) is set in the first half of the intake stroke. 【請求項２】微小作動用カム（26,76）による微小リフ
ト曲線（C2）の最大リフト部（C2M）は、開閉作動用カ
ム（25,74）による開弁リフト曲線（C1,C1′）の最大リ
フト部（C1M,C1M′）よりもクランク角に沿う後方側に
設定されることを特徴とする請求項第項記載の内燃機
関。 2. The maximum lift portion (C 2M ) of the minute lift curve (C 2 ) formed by the minute operation cams (26, 76) is the valve opening lift curve (C 1 , 'maximum lift portion (C 1M, C 1M) of') an internal combustion engine as in claim claim, wherein the set to the rear side along the crank angle than C 1. 【請求項３】動弁装置（18,18′）は、カムシャフト（1
9,19′）の各カム（25,26;74,75,76）および一対の吸気
弁（VI1,VI2）間で相互に隣接して設けられる複数の弁
駆動部材（20,21;71,72,73）を備え、弁作動特性切換手
段（35,35′）は、隣接した弁駆動部材（20,21;71,72,7
3）相互の連結および連結解除を切換可能に構成される
ことを特徴とする請求項第項又は第項記載の内燃機
関。3. The valve operating device (18, 18 ') includes a camshaft (1
9,19 ') cams (25,26; 74,75,76) and a plurality of valve drive members (20,21;) provided adjacent to each other between the pair of intake valves (V I1 , V I2 ). 71, 72, 73), and the valve operating characteristic switching means (35, 35 ') is provided with the adjacent valve driving members (20, 21; 71, 72, 7).
3) The internal combustion engine according to claim 1 or 2, which is configured to be switchable between mutual connection and disconnection.
JP2213376A 1990-08-10 1990-08-10 Internal combustion engine Expired - Fee Related JPH086570B2 (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
JP2213376A JPH086570B2 (en) 1990-08-10 1990-08-10 Internal combustion engine
US07/742,831 US5209201A (en) 1990-08-10 1991-08-08 Internal combustion engine
CA002048913A CA2048913C (en) 1990-08-10 1991-08-09 Internal combustion engine
AT91307403T ATE124108T1 (en) 1990-08-10 1991-08-12 INTERNAL COMBUSTION ENGINE.
DE69110573T DE69110573T2 (en) 1990-08-10 1991-08-12 Internal combustion engine.
EP91307403A EP0470869B1 (en) 1990-08-10 1991-08-12 Internal combustion engine
ES91307403T ES2076476T3 (en) 1990-08-10 1991-08-12 INTERNAL COMBUSTION ENGINE.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2213376A JPH086570B2 (en) 1990-08-10 1990-08-10 Internal combustion engine

Publications (2)

Publication Number Publication Date
JPH0494407A JPH0494407A (en) 1992-03-26
JPH086570B2 true JPH086570B2 (en) 1996-01-24

Family

ID=16638169

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2213376A Expired - Fee Related JPH086570B2 (en) 1990-08-10 1990-08-10 Internal combustion engine

Country Status (1)

Country Link
JP (1) JPH086570B2 (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3631770B2 (en) * 1993-01-22 2005-03-23 本田技研工業株式会社 Intake device for internal combustion engine
JP2517119Y2 (en) * 1993-09-28 1996-11-13 本田技研工業株式会社 Valve train for internal combustion engine
FR2830899B1 (en) * 2001-10-12 2004-06-11 Renault METHOD FOR CONTROLLING A CAMLESS MOTOR
WO2012014288A1 (en) * 2010-07-27 2012-02-02 トヨタ自動車株式会社 Internal combustion engine controller
JP5758253B2 (en) * 2011-09-25 2015-08-05 本田技研工業株式会社 Multi-cylinder internal combustion engine

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62288305A (en) * 1986-06-04 1987-12-15 Fuji Heavy Ind Ltd Control of valve of car engine
JPS63124817A (en) * 1986-11-12 1988-05-28 Honda Motor Co Ltd Valve actuating device of internal combustion engine
JPS6480735A (en) * 1987-09-22 1989-03-27 Honda Motor Co Ltd Multiple cylinder internal combustion engine

Also Published As

Publication number Publication date
JPH0494407A (en) 1992-03-26

Similar Documents

Publication Publication Date Title
EP0703351B1 (en) Valve operating system for multi-cylinder internal combustion engine
EP0470869B1 (en) Internal combustion engine
US7377249B1 (en) Outward-opening gas-exchange valve system for an internal combustion engine
JP3631770B2 (en) Intake device for internal combustion engine
JP5580480B2 (en) 6 cycle engine
EP1234958B1 (en) A method of and apparatus for controlling quantity of air drawn into internal combustion engine
JPH0893515A (en) Valve gear characteristics and air-fuel ratio change-over control method in internal combustion engine
JP2762216B2 (en) Internal combustion engine
JPH086570B2 (en) Internal combustion engine
Kreuter et al. The META VVH system-A continuously variable valve timing system
JPH0830433B2 (en) Internal combustion engine
JP4670546B2 (en) Spark ignition type 4-cycle engine
JPH0797938A (en) Internal combustion engine
JP4233915B2 (en) Engine valve gear
JP3388058B2 (en) Ignition control device for engine
JP2632208B2 (en) Intake device for internal combustion engine
JP3213039B2 (en) Variable compression ratio engine
JPH08170512A (en) Engine with valve opening/closing mechanism
JPH07107367B2 (en) Internal combustion engine intake system
JP3127317B2 (en) Exhaust gas recirculation system for multi-cylinder internal combustion engine
JP3453788B2 (en) Engine with storage room
JPH0811935B2 (en) Intake control device for internal combustion engine
JP4878694B2 (en) Internal combustion engine
JP2588362B2 (en) Multi-cylinder internal combustion engine
JPH11324739A (en) Controller for direct gasoline-injection engine

Legal Events

Date Code Title Description
FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20080124

Year of fee payment: 12

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20090124

Year of fee payment: 13

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20100124

Year of fee payment: 14

LAPS Cancellation because of no payment of annual fees