JPS641470Y2 - - Google Patents
Info
- Publication number
- JPS641470Y2 JPS641470Y2 JP1981073897U JP7389781U JPS641470Y2 JP S641470 Y2 JPS641470 Y2 JP S641470Y2 JP 1981073897 U JP1981073897 U JP 1981073897U JP 7389781 U JP7389781 U JP 7389781U JP S641470 Y2 JPS641470 Y2 JP S641470Y2
- Authority
- JP
- Japan
- Prior art keywords
- scavenging
- passage
- cylinder
- pressure relief
- engine
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 230000002000 scavenging effect Effects 0.000 claims description 58
- 230000006835 compression Effects 0.000 description 16
- 238000007906 compression Methods 0.000 description 16
- 230000007423 decrease Effects 0.000 description 6
- 238000002485 combustion reaction Methods 0.000 description 5
- 238000009792 diffusion process Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 2
- 238000003915 air pollution Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000010687 lubricating oil Substances 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F1/00—Cylinders; Cylinder heads
- F02F1/18—Other cylinders
- F02F1/22—Other cylinders characterised by having ports in cylinder wall for scavenging or charging
-
- 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
- F02B75/00—Other engines
- F02B75/02—Engines characterised by their cycles, e.g. six-stroke
- F02B2075/022—Engines characterised by their cycles, e.g. six-stroke having less than six strokes per cycle
- F02B2075/025—Engines characterised by their cycles, e.g. six-stroke having less than six strokes per cycle two
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Cylinder Crankcases Of Internal Combustion Engines (AREA)
- Output Control And Ontrol Of Special Type Engine (AREA)
Description
【考案の詳細な説明】
（産業上の利用分野）
本考案は、２サイクルエンジンのシリンダに関
する。[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a cylinder for a two-stroke engine.
（従来の技術）
第４図に示す如く、２サイクルエンジンのシリ
ンダａにおいて、排気ポートｂのシリンダ側開口
部上端に切欠溝ｃを設け、燃焼室内の圧力を切欠
溝ｃから排気ポートｂへ逃がすことにより、リコ
イルスタータ等によるエンジン起動時の起動トル
クの低減を図るものは知られている。(Prior art) As shown in Fig. 4, in the cylinder a of a two-stroke engine, a notch c is provided at the upper end of the cylinder side opening of the exhaust port b, and the pressure in the combustion chamber is released from the notch groove c to the exhaust port b. It is known to reduce the starting torque when starting the engine using a recoil starter or the like.
また、第４図に鎖線で示す如くシリンダ壁に排
気ポートｂよりも上方位置から吸気ポートｄに至
るバイパス通路ｅを設け、このバイパス通路ｅを
介して圧力を吸気ポートｄに逃がすものも知られ
ている。 It is also known that a bypass passage e is provided in the cylinder wall from a position above the exhaust port b to the intake port d, as shown by the chain line in FIG. 4, and the pressure is released to the intake port d via the bypass passage e. ing.
（考案が解決しようとする課題）
しかし、上記切欠溝ｃを設けたものにおいて
は、圧縮行程において新気ガスの一部が切欠溝ｃ
から排気ポートｂへ流出するという問題がある。
一方、上記バイパス通路ｅを設けたものにおいて
は、膨張行程において既燃ガスの一部がバイパス
通路ｅより吸気ポートｄへ流入し、続いてクラン
クケース内で新気ガス中へ拡散されるため、給気
比が低くなつてしまう。(Problem to be solved by the invention) However, in the case where the above-mentioned notched groove c is provided, part of the fresh gas is absorbed into the notched groove c during the compression stroke.
There is a problem that the air flows out from the air to the exhaust port b.
On the other hand, in the case where the bypass passage e is provided, a part of the burnt gas flows into the intake port d from the bypass passage e during the expansion stroke, and is subsequently diffused into fresh gas within the crankcase. The air supply ratio becomes low.
そうして、上述の切欠溝やバイパス通路という
圧力逃がし通路をエンジンの全運転期間にわたつ
てピストンの摺動により開閉する方式を採用する
場合、エンジンの通常運転時においても上述の排
気ポートへの新気の流出やクランクケース内の新
気ガス中への既燃ガスの拡散が生ずるものであ
り、このことは、上記新気の流出が燃料消費率の
上昇や大気汚染の原因となり、あるいは上記既燃
ガスの拡散がエンジンの性能の低下を招くという
点で重要な問題となる。 If a method is adopted in which the above-mentioned pressure relief passages such as notched grooves and bypass passages are opened and closed by sliding pistons throughout the entire operating period of the engine, even during normal operation of the engine, the above-mentioned exhaust port is closed. This causes the outflow of fresh air and the diffusion of burnt gas into the fresh air gas in the crankcase. Diffusion of burnt gas is an important problem in that it causes deterioration in engine performance.
これに対し、上記バイパス通路のような圧力逃
がし通路にバルブを設けて、エンジンの通常運転
時にはこれを閉塞するということが考えられるの
であるが、単に圧力逃がし機構の構造が複雑にな
るだけでなく、汎用エンジンにおいてはバルブ操
作レバーの設置場所の確保が難しいとともに、エ
ンジンの起動操作の都度、バルブの開閉操作を必
要とし、さらには、バルブの締め忘れを招く懸念
もある。 On the other hand, it is conceivable to provide a valve in a pressure relief passage such as the bypass passage mentioned above and close it during normal operation of the engine, but this would not only complicate the structure of the pressure relief mechanism but also In a general-purpose engine, it is difficult to secure a place to install a valve operating lever, and the valve must be opened and closed each time the engine is started, and furthermore, there is a concern that the valve may be forgotten to be tightened.
（課題を解決するための手段）
本考案は、このような課題に対して、燃焼室内
の圧力を掃気通路に逃がすようにして、排気ポー
トへの新気の流出やクランクケース内の新気ガス
中への既燃ガスの拡散を防止するとともに、圧力
逃がし通路に開閉用のバルブを設けずとも、圧縮
行程での燃焼室に対する上記通路の連通時間は、
エンジンの起動時には長く、エンジンの通常運転
時には瞬時であつて、このことにより、エンジン
の起動時には圧縮比を低減しながら、通常運転時
には圧縮比の低減を抑えることが可能であること
を利用し、圧力逃がし通路をエンジンの全運転期
間にわたりピストンの摺動により開閉する方式を
採用するものである。(Means for solving the problem) The present invention solves this problem by releasing the pressure inside the combustion chamber to the scavenging passage, thereby reducing the flow of fresh air to the exhaust port and the fresh air gas inside the crankcase. In addition to preventing the diffusion of burnt gas inside, the communication time of the passage to the combustion chamber during the compression stroke is
Taking advantage of the fact that the compression ratio is long when the engine is started, and instantaneous when the engine is running normally, and thus it is possible to reduce the compression ratio when the engine is started, while suppressing the reduction in the compression ratio during normal operation. A method is adopted in which the pressure relief passage is opened and closed by the sliding movement of a piston throughout the entire operating period of the engine.
すなわち、本考案に係る２サイクルエンジンの
シリンダは、１または２以上の掃気通路を設けた
ものにおいて、一端が排気ポートよりも上方のシ
リンダ壁内面に、他端が掃気通路にそれぞれ開口
し、エンジンの全運転期間にわたつてピストンの
摺動により開閉される圧力逃がし通路が形成され
ていることを特徴とする。 That is, the cylinder of the two-stroke engine according to the present invention has one or more scavenging passages, one end of which opens on the inner surface of the cylinder wall above the exhaust port, and the other end of which opens into the scavenging passage. A pressure relief passage is formed that is opened and closed by the sliding movement of the piston over the entire operating period.
（作用）
上記２サイクルエンジンのシリンダにおいて
は、圧力逃がし通路はエンジンの全運転期間にわ
たつてピストンの摺動により開閉されるが、シリ
ンダ内のガスが圧力逃がし通路を通つて掃気通路
に流れる量は、シリンダ内と掃気通路間の圧力差
が同じであれば、シリンダ内に対する圧力逃がし
通路の連通時間に比例する。そして、シリンダ内
のガスの圧縮は、上昇行程のピストンの上縁が排
気ポートの上縁に達した時から始まるが、エンジ
ン起動時のようにエンジン回転数が極めて低いと
きは、圧縮開始から圧力逃がし通路がピストンで
閉塞されるまでの時間、つまり、圧力逃がし通路
の連通時間が長い。しかし、エンジン回転数が高
くなるにつれて上記連通時間は短くなり、高速回
転時には圧力逃がし通路は燃焼室に対し瞬時しか
連通しないことになる。(Function) In the cylinder of the two-stroke engine mentioned above, the pressure relief passage is opened and closed by the sliding movement of the piston over the entire operating period of the engine, but the amount of gas in the cylinder that flows through the pressure relief passage to the scavenging passage is is proportional to the communication time of the pressure relief passage with respect to the cylinder, if the pressure difference between the inside of the cylinder and the scavenging passage is the same. Compression of the gas in the cylinder begins when the upper edge of the piston on its upward stroke reaches the upper edge of the exhaust port. The time it takes for the relief passage to be closed by the piston, that is, the communication time of the pressure relief passage is long. However, as the engine speed increases, the communication time becomes shorter, and the pressure relief passage communicates with the combustion chamber only momentarily during high-speed rotation.
従つて、上記連通時間が極めて短い通常運転時
にはシリンダ内のガスが圧力逃がし通路へ流れる
量は少なく、この圧力逃がし通路があつても圧縮
比はあまり低下しないが、上記連通時間が長いエ
ンジンの起動時には、圧力逃がし通路へ流れるガ
スの量が多くなり、この圧力逃がし通路が閉じら
れるまでは圧力の上昇はあまりない。よつて、起
動時は通常運転時に比べて圧縮比が低くなつて起
動トルクが低減する。 Therefore, during normal operation when the communication time is extremely short, the amount of gas in the cylinder flowing into the pressure relief passage is small, and even if this pressure relief passage exists, the compression ratio does not decrease much, but when starting the engine, the communication time is long. Sometimes, there is a large amount of gas flowing into the pressure relief passage, and the pressure does not increase significantly until the pressure relief passage is closed. Therefore, at startup, the compression ratio is lower than during normal operation, and the startup torque is reduced.
また、この圧縮行程においては、新気ガスの一
部は掃気通路に流れるだけであり、外部には流出
しない。さらに、膨張行程において、既燃ガスの
一部は圧力逃がし通路を経て掃気通路に流入する
が、そのまま掃気通路に滞留するためクランクケ
ース内へ流入する既燃ガスは微量である。また、
掃気行程においては、上記膨張行程で掃気通路に
滞留した既燃ガスが排気ポートへ吹き抜ける掃気
初期のガスとなるため、排気ポートへの新気の吹
き抜け量が少なくなる。 Further, in this compression stroke, a part of the fresh gas only flows into the scavenging passage and does not flow out to the outside. Furthermore, during the expansion stroke, a portion of the burnt gas flows into the scavenging passage through the pressure relief passage, but since it stays in the scavenging passage as it is, only a small amount of the burnt gas flows into the crankcase. Also,
In the scavenging stroke, the burnt gas that remained in the scavenging passage during the expansion stroke becomes the initial scavenging gas that blows through to the exhaust port, so the amount of fresh air that blows through to the exhaust port decreases.
（考案の効果）
従つて、本考案によれば、一端が排気ポートよ
りも上方のシリンダ壁内面に、他端が掃気通路に
それぞれ開口し、エンジンの全運転期間にわたつ
てピストンの摺動により開閉される圧力逃がし通
路を形成したから、エンジンの起動トルクの低減
が図れることになり、また、排気ポートへの新気
の流出やクランクケース内の新気ガス中への既燃
ガスの拡散の問題はなく、且つ圧力逃がし通路を
バルブで開閉する必要はないことから、簡単な構
造で燃料消費率の上昇や大気汚染、あるいはエン
ジンの性能の低下の問題を招くことなく、エンジ
ンの始動性を向上せしめることができる。(Effect of the invention) Therefore, according to the invention, one end is opened on the inner surface of the cylinder wall above the exhaust port, and the other end is opened in the scavenging passage, and the piston slides through the entire operating period of the engine. By creating a pressure relief passage that opens and closes, it is possible to reduce the engine starting torque, and it also prevents fresh air from flowing into the exhaust port and burning gas from diffusing into the fresh air in the crankcase. There is no problem, and since there is no need to open and close the pressure relief passage with a valve, the simple structure improves engine startability without increasing fuel consumption, air pollution, or deteriorating engine performance. It can be improved.
（実施例）
以下、本考案の実施例を図面に基づいて説明す
る。(Example) Hereinafter, an example of the present invention will be described based on the drawings.
＜実施例 １＞
本例は第１図に示し、１は２サイクルエンジン
で、シリンダヘツド２、シリンダ３及びクランク
ケース４が順に連設され、ピストン５のピストン
ピン６とクランクシヤフト７のクランクピン８と
がコンロツド９で連結されている。１０はシリン
ダ側掃気通路、１１はクランクケース側掃気通
路、１２は排気ポート、１３は掃気内壁である。<Example 1> This example is shown in FIG. 1, and 1 is a two-stroke engine, in which a cylinder head 2, a cylinder 3, and a crankcase 4 are connected in sequence, and a piston pin 6 of a piston 5 and a crank pin of a crankshaft 7 are connected. 8 are connected by connecting rod 9. 10 is a cylinder side scavenging passage, 11 is a crankcase side scavenging passage, 12 is an exhaust port, and 13 is a scavenging inner wall.
シリンダ３には、排気ポート１２のシリンダ側
開口部よりも上位置においてシリンダ壁を内外に
貫通した横孔１５と、シリンダ側掃気通路１０よ
りシリンダ上端に至り、前記横孔１５に直交した
縦孔１６とが形成されている。そして、上記横孔
１５の外側開口はプラグ１７で、また、縦孔１６
の上端開口はガスケツト１８でそれぞれ閉塞され
ており、これにより、上記横孔１５と縦孔１６と
で、一端が排気ポート１２よりも上方のシリンダ
壁内面に、他端がシリンダ側掃気通路１０にそれ
ぞれ開口し、エンジンの全運転期間にわたつてピ
ストン５の摺動により開閉される圧力逃がし通路
１９が構成されている。なお、第１図中、２０は
ピストンピン潤滑油孔である。 The cylinder 3 has a horizontal hole 15 that penetrates the cylinder wall inside and out at a position above the cylinder side opening of the exhaust port 12, and a vertical hole that reaches the upper end of the cylinder from the cylinder side scavenging passage 10 and is perpendicular to the horizontal hole 15. 16 are formed. The outer opening of the horizontal hole 15 is a plug 17, and the vertical hole 16 is a plug 17.
The upper end openings are each closed by a gasket 18, so that the horizontal hole 15 and the vertical hole 16 have one end connected to the inner surface of the cylinder wall above the exhaust port 12, and the other end connected to the cylinder side scavenging passage 10. A pressure relief passage 19 is formed, which is opened and closed by the sliding movement of the piston 5 over the entire operating period of the engine. In addition, in FIG. 1, 20 is a piston pin lubricating oil hole.
上記構造において、シリンダ内のガスの圧縮
は、上昇行程のピストン５の上縁が排気ポート１
２の上縁に達した時から始まり、圧縮開始から圧
力逃がし通路１９がピストン５で閉塞されるま
で、シリンダ３内の新気ガスの一部が圧力逃がし
通路１９を介して掃気通路１０，１１に流れ圧縮
比が低下する。この場合、エンジン起動時のよう
にエンジン回転数が極めて低いときは、圧縮開始
から圧力逃がし通路１９がピストン５で閉塞され
るまでの時間、つまり、圧力逃がし通路１９の連
通時間が長く、エンジン回転数が高くなるにつれ
て上記連通時間が短くなり、高速回転時には圧力
逃がし通路１９は燃焼室に対し瞬時しか連通しな
いことになる。 In the above structure, the gas in the cylinder is compressed when the upper edge of the piston 5 on the upward stroke reaches the exhaust port 1.
Starting from the time when the upper edge of the cylinder 2 is reached, a part of the fresh gas in the cylinder 3 passes through the pressure relief passage 19 to the scavenging passages 10 and 11 from the start of compression until the pressure relief passage 19 is closed by the piston 5. The flow compression ratio decreases. In this case, when the engine speed is extremely low, such as when starting the engine, the time from the start of compression until the pressure relief passage 19 is closed by the piston 5, that is, the communication time of the pressure relief passage 19 is long, and the engine speed As the number increases, the communication time becomes shorter, and at high speed rotation, the pressure relief passage 19 communicates with the combustion chamber only momentarily.
従つて、上記連通時間が極めて短い通常運転時
にはシリンダ内のガスが圧力逃がし通路１９へ流
れる量は少なく、この圧力逃がし通路１９があつ
ても圧縮比はあまり低下しないが、上記連通時間
が長いエンジンの起動時には、圧力逃がし通路１
９へ流れるガスの量が多くなり、この圧力逃がし
通路１９が閉じられるまでは圧力の上昇はあまり
なく、通常運転時に比べて圧縮比が低くなり、上
記起動トルクが低減されることになる。これによ
り、小さな起動トルクで大きな起動回転速度が得
られるため、エンジンの始動性が向上し、また、
圧縮行程を容易に乗り切ることができるようにな
るため、起動操作時の逆転シヨツク、所謂ケツチ
ンが防止される。 Therefore, during normal operation when the communication time is extremely short, the amount of gas in the cylinder flowing into the pressure relief passage 19 is small, and even if this pressure relief passage 19 is provided, the compression ratio does not decrease much, but in an engine where the communication time is long. When starting up, pressure relief passage 1
The amount of gas flowing into the engine 9 increases and the pressure does not increase much until the pressure relief passage 19 is closed, the compression ratio becomes lower than during normal operation, and the starting torque is reduced. As a result, a large starting rotation speed can be obtained with a small starting torque, improving engine starting performance.
Since the compression stroke can be easily overcome, a reverse shock or so-called butt during a starting operation is prevented.
また、エンジンの起動時及び通常運転時におい
て、上記圧縮行程では、新気ガスの一部は掃気通
路１０，１１に流れるだけであり、外部には流出
しない。さらに、膨張行程において、既燃ガスの
一部は圧力逃がし通路１９を経て掃気通路１０，
１１に流入するが、そのまま掃気通路１０，１１
に滞留するためクランクケース４内へ流入する既
燃ガスは微量であり、新気ガスとの混合はほとん
ど生じない。また、掃気行程においては、上記膨
張行程で掃気通路１０，１１に滞留した既燃ガス
が排気ポート１２へ吹き抜ける掃気初期のガスと
なるため、排気ポート１２への新気の吹き抜け量
が少なくなる。 Furthermore, during the engine startup and normal operation, a portion of the fresh gas only flows into the scavenging passages 10 and 11 during the compression stroke, and does not flow out to the outside. Further, during the expansion stroke, a part of the burnt gas passes through the pressure relief passage 19 and the scavenging passage 10.
11, but directly flows into the scavenging passages 10, 11.
The amount of burned gas that flows into the crankcase 4 is very small and hardly mixes with fresh gas. Furthermore, in the scavenging stroke, the burnt gas that has remained in the scavenging passages 10 and 11 during the expansion stroke becomes gas at the initial stage of scavenging that blows through to the exhaust port 12, so the amount of fresh air that blows through to the exhaust port 12 is reduced.
＜実施例 ２＞
本例はその要部を第２図に示し、圧力逃がし通
路を設ける位置を特定したものである。<Example 2> In this example, the main part is shown in FIG. 2, and the position where the pressure relief passage is provided is specified.
すなわち、シリンダ３には排気ポート１２側か
ら吸気ポート２１側に至る両半円周に沿つてそれ
ぞれ複数の掃気通路２２〜２４が形成されてお
り、排気ポート１２から最も遠い位置の掃気通路
２４に圧力逃がし通路２５の一端が開口してい
る。 That is, a plurality of scavenging passages 22 to 24 are formed in the cylinder 3 along both semicircumferences from the exhaust port 12 side to the intake port 21 side. One end of the pressure relief passage 25 is open.
本例においては、排気ポート１２から最も遠い
位置の掃気通路２４に既燃ガスが滞留するが、各
掃気通路２２〜２４から出る掃気ガスはシリンダ
内面に沿つて上方へ移動し、ループを描いた後、
排気ポート１２に至ることから、排気ポート１２
から最も遠い位置の掃気通路２４から出る掃気初
期のガス、すなわち前記既燃ガスが他の掃気通路
２２，２３から出る新気ガスよりも先に排気ポー
ト１２へ吹き抜けるため、新気ガスの吹き抜け量
が減少する。 In this example, burnt gas remains in the scavenging passage 24 located farthest from the exhaust port 12, but the scavenging gas exiting from each scavenging passage 22 to 24 moves upward along the inner surface of the cylinder, forming a loop. rear,
Since it reaches the exhaust port 12, the exhaust port 12
Since the gas at the initial stage of scavenging, that is, the burnt gas, which exits from the scavenging passage 24 at the farthest position from the scavenging passage 24, blows through to the exhaust port 12 before the fresh gas exiting from the other scavenging passages 22 and 23, the amount of fresh gas blown through is small. decreases.
＜実施例 ３＞
本例はその要部を第３図に示し、圧力逃がし通
路を設けた掃気通路２４の開口時期を他の掃気通
路２２，２３のそれよりも早めたものである。<Embodiment 3> The main part of this example is shown in FIG. 3, and the scavenging passage 24 provided with a pressure relief passage is opened earlier than the other scavenging passages 22 and 23.
すなわち、複数の掃気通路２２〜２４のうち、
排気ポート１２から最も遠い位置の掃気通路２４
は、シリンダ側開口部２９の上端が他の掃気通路
２２，２３のシリンダ側開口部２７，２８よりも
上死点側に位置している。そして、シリンダ壁内
面には上記掃気通路２４の上端より排気ポート１
２よりも上方位置に至る溝が形成されていて、こ
の溝を圧力逃がし通路２６としている。 That is, among the plurality of scavenging passages 22 to 24,
Scavenging passage 24 located farthest from the exhaust port 12
In this case, the upper end of the cylinder-side opening 29 is located closer to the top dead center than the cylinder-side openings 27 and 28 of the other scavenging passages 22 and 23. An exhaust port 1 is provided on the inner surface of the cylinder wall from the upper end of the scavenging passage 24.
A groove extending to a position above 2 is formed, and this groove serves as a pressure relief passage 26.
従つて、本例においては、圧力逃がし通路２６
を設けた掃気通路２４が他の掃気通路２２，２３
よりも先に開口するため、前記掃気通路２４に滞
留した既燃ガスが他の掃気通路２２，２３から流
出する掃気ガス、すなわち、新気ガスよりも先に
シリンダ内に流出し、この既燃ガスが主として排
気ポート１２へ吹き抜ける掃気初期のガスとな
り、排気ポート１２への新気ガスの吹き抜け量が
減少する。 Therefore, in this example, the pressure relief passage 26
The scavenging passage 24 provided with the scavenging passages 22 and 23
Since the scavenging passage 24 opens earlier than the scavenging passage 24, the burnt gas remaining in the scavenging passage 24 flows out into the cylinder before the scavenging gas flowing out from the other scavenging passages 22, 23, that is, fresh air gas, and this burned gas The gas mainly becomes the gas at the initial stage of scavenging that blows through to the exhaust port 12, and the amount of fresh gas that blows through to the exhaust port 12 decreases.
第１図乃至第３図は本考案の実施例を示し、第
１図は実施例１の２サイクルエンジンを示す中央
縦断面図、第２図は実施例２のシリンダを第１図
の−線において示す断面図、第３図は実施例
３のシリンダを示す第２図と同様の図、第４図は
従来例を示す第２図と同様の図である。
１……２サイクルエンジン、２……シリンダヘ
ツド、３……シリンダ、４……クランクケース、
５……ピストン、１０，１１，２２〜２４……掃
気通路、１２……排気ポート、１３……掃気内
壁、１５……横孔、１６……縦孔、１９，２５，
２６……圧力逃がし通路、２１……吸気ポート、
２７〜２９……掃気通路のシリンダ側開口部。
1 to 3 show embodiments of the present invention, FIG. 1 is a central longitudinal cross-sectional view showing a two-stroke engine of embodiment 1, and FIG. 2 shows a cylinder of embodiment 2 taken along the line - in FIG. 3 is a view similar to FIG. 2 showing the cylinder of the third embodiment, and FIG. 4 is a view similar to FIG. 2 showing the conventional example. 1... 2-stroke engine, 2... cylinder head, 3... cylinder, 4... crank case,
5...Piston, 10, 11, 22-24...Scavenging passage, 12...Exhaust port, 13...Scavenging inner wall, 15...Horizontal hole, 16...Vertical hole, 19, 25,
26...Pressure relief passage, 21...Intake port,
27 to 29... Cylinder side opening of the scavenging passage.
Claims (1)
ルエンジンのシリンダにおいて、一端が排気ポ
ートよりも上方のシリンダ壁内面に、他端が掃
気通路にそれぞれ開口し、エンジンの全運転期
間にわたつてピストンの摺動により開閉される
圧力逃がし通路が形成されていることを特徴と
する２サイクルエンジンのシリンダ。 (2) 複数の掃気通路が設けられ、圧力逃がし通路
が開口した掃気通路はシリンダ側開口部の上端
が他の掃気通路のシリンダ側開口部の上端より
も上死点側に位置し、圧力逃がし通路が開口し
た掃気通路の開口時期を他の掃気通路の開口時
期よりも早くした実用新案登録請求の範囲第１
項に記載の２サイクルエンジンのシリンダ。 (3) 複数の掃気通路が設けられ、圧力逃がし通路
が排気ポートより最も遠い位置の掃気通路に開
口した実用新案登録請求の範囲第１項または第
２項に記載の２サイクルエンジンのシリンダ。[Claims for Utility Model Registration] (1) In a two-stroke engine cylinder provided with one or more scavenging passages, one end opens on the inner surface of the cylinder wall above the exhaust port, and the other end opens into the scavenging passage. A cylinder for a two-stroke engine, characterized in that a pressure relief passage is formed that is opened and closed by sliding of a piston over the entire operating period of the engine. (2) In the scavenging passage where a plurality of scavenging passages are provided and the pressure relief passage is open, the upper end of the cylinder side opening is located closer to the top dead center than the upper end of the cylinder side opening of other scavenging passages, and the pressure relief passage is Scope of Utility Model Registration Claim No. 1 in which the opening timing of the scavenging passage where the passage is opened is earlier than the opening timing of other scavenging passages.
The cylinder of the two-stroke engine described in section. (3) A cylinder for a two-stroke engine according to claim 1 or 2, in which a plurality of scavenging passages are provided, and the pressure relief passage opens at the scavenging passage located furthest from the exhaust port.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1981073897U JPS641470Y2 (en) | 1981-05-20 | 1981-05-20 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1981073897U JPS641470Y2 (en) | 1981-05-20 | 1981-05-20 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57186635U JPS57186635U (en) | 1982-11-26 |
| JPS641470Y2 true JPS641470Y2 (en) | 1989-01-13 |
Family
ID=29869668
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1981073897U Expired JPS641470Y2 (en) | 1981-05-20 | 1981-05-20 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS641470Y2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59139519U (en) * | 1983-03-08 | 1984-09-18 | 川崎重工業株式会社 | 2 cycle engine |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1386177A (en) * | 1972-08-17 | 1975-03-05 | Norton Villiers Ltd | Internal combustion engines |
| JPS5421714B2 (en) * | 1975-07-18 | 1979-08-01 | ||
| JPS5611623U (en) * | 1979-07-04 | 1981-01-31 | ||
| JPS5673897A (en) * | 1979-11-16 | 1981-06-18 | Hitachi Ltd | Power source control system for nulcear fusion reactor |
| JPS57113963A (en) * | 1980-12-29 | 1982-07-15 | Yamaha Motor Co Ltd | Interlocking device for choke and decompressor in internal-combustion engine |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5851376Y2 (en) * | 1977-07-15 | 1983-11-22 | 川崎重工業株式会社 | Scavenging device for crank chamber compression type 2-stroke engine |
-
1981
- 1981-05-20 JP JP1981073897U patent/JPS641470Y2/ja not_active Expired
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1386177A (en) * | 1972-08-17 | 1975-03-05 | Norton Villiers Ltd | Internal combustion engines |
| JPS5421714B2 (en) * | 1975-07-18 | 1979-08-01 | ||
| JPS5611623U (en) * | 1979-07-04 | 1981-01-31 | ||
| JPS5673897A (en) * | 1979-11-16 | 1981-06-18 | Hitachi Ltd | Power source control system for nulcear fusion reactor |
| JPS57113963A (en) * | 1980-12-29 | 1982-07-15 | Yamaha Motor Co Ltd | Interlocking device for choke and decompressor in internal-combustion engine |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57186635U (en) | 1982-11-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6513465B2 (en) | Two-stroke internal combustion engine | |
| US5628295A (en) | Two-stroke internal combustion engine | |
| EP0382063A1 (en) | 2-Cycle multi-cylinder engine | |
| US4167161A (en) | Directional auxiliary intake injection for internal combustion engine | |
| US5027757A (en) | Two-stroke cycle engine cylinder construction | |
| JPS587058Y2 (en) | Crank chamber compression type 2-stroke engine | |
| JP3406119B2 (en) | 2-stroke diesel engine with swirl chamber auxiliary combustion chamber | |
| JPS641470Y2 (en) | ||
| US4938192A (en) | Piston cylinder combination with engine cylinder wall having valve ports and combustion chamber | |
| US6145483A (en) | Two-cycle internal combustion engine | |
| AU605984B2 (en) | Decompression device in a two-cycle engine | |
| US5603291A (en) | Internal combustion engine with valve built into piston head | |
| US5524578A (en) | Two-cycle engine having improved idle relief | |
| JPS595780B2 (en) | 2 Cycle engine assembly | |
| JP3622019B2 (en) | Internal combustion engine | |
| JP3948081B2 (en) | Spark ignition internal combustion engine | |
| US5540195A (en) | Vuka two-stroke engine | |
| JPH0335864Y2 (en) | ||
| JP2526986Y2 (en) | Engine piston structure | |
| JPH0110418Y2 (en) | ||
| JPH0123650B2 (en) | ||
| JPH0420991Y2 (en) | ||
| JPS5819303Y2 (en) | 2 cycle engine | |
| JPS5842578Y2 (en) | Air supply system for two-stroke internal combustion engine | |
| JPS5933843Y2 (en) | 2 cylinder 2 cycle engine |