JPS6314212B2 - - Google Patents
Info
- Publication number
- JPS6314212B2 JPS6314212B2 JP16161782A JP16161782A JPS6314212B2 JP S6314212 B2 JPS6314212 B2 JP S6314212B2 JP 16161782 A JP16161782 A JP 16161782A JP 16161782 A JP16161782 A JP 16161782A JP S6314212 B2 JPS6314212 B2 JP S6314212B2
- Authority
- JP
- Japan
- Prior art keywords
- piston
- crank
- crankshaft
- cylinder
- small end
- 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
- 238000002485 combustion reaction Methods 0.000 claims description 19
- 239000000203 mixture Substances 0.000 description 6
- 239000000446 fuel Substances 0.000 description 5
- 238000004880 explosion Methods 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 3
- 230000006835 compression Effects 0.000 description 3
- 238000007906 compression Methods 0.000 description 3
- 235000014676 Phragmites communis Nutrition 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000002000 scavenging effect Effects 0.000 description 2
- 230000001133 acceleration Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 239000010687 lubricating oil Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000005192 partition Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 230000010363 phase shift Effects 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B75/00—Other engines
- F02B75/16—Engines characterised by number of cylinders, e.g. single-cylinder engines
- F02B75/18—Multi-cylinder engines
- F02B75/22—Multi-cylinder engines with cylinders in V, fan, or star arrangement
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
- F16F15/22—Compensation of inertia forces
- F16F15/26—Compensation of inertia forces of crankshaft systems using solid masses, other than the ordinary pistons, moving with the system, i.e. masses connected through a kinematic mechanism or gear system
- F16F15/264—Rotating balancer shafts
-
- 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
- F02B75/16—Engines characterised by number of cylinders, e.g. single-cylinder engines
- F02B75/18—Multi-cylinder engines
- F02B2075/1804—Number of cylinders
- F02B2075/1812—Number of cylinders three
-
- 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
- F02B67/00—Engines characterised by the arrangement of auxiliary apparatus not being otherwise provided for, e.g. the apparatus having different functions; Driving auxiliary apparatus from engines, not otherwise provided for
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Aviation & Aerospace Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Shafts, Cranks, Connecting Bars, And Related Bearings (AREA)
Description
【発明の詳細な説明】
本発明は、一次慣性力による振動を取除くよう
にした三気筒内燃機関に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a three-cylinder internal combustion engine that eliminates vibrations caused by primary inertia force.
従来、三気筒内燃機関において一次慣性力によ
る振動を取除くようにしたものとしては、三本の
クランクピンをクランク角上120゜の間隔をおいて
配置したものが知られているが、それはクランク
ピンの位相ずれのために、クランク軸に不釣合偶
力が発生する欠点がある。 Conventionally, a known method for removing vibrations caused by primary inertia in a three-cylinder internal combustion engine is to arrange three crank pins at an interval of 120° above the crank angle. There is a drawback that an unbalanced couple is generated on the crankshaft due to the phase shift of the pins.
本発明は、そのような不釣合い偶力を発生させ
ることなく、一次慣性力による振動を取除くよう
にした、簡単有効な三気筒内燃機関を提供するこ
とを目的とする。 An object of the present invention is to provide a simple and effective three-cylinder internal combustion engine that eliminates vibrations caused by primary inertial force without generating such an unbalanced couple.
以下、図面により本発明の一実施例について説
明すると、第１図においてオートバイの車体フレ
ームＦに本発明の三気筒内燃機関Ｅが搭載され、
この機関Ｅのクランク軸１及びこれに駆動される
変速機の出力軸２ｏは前，後輪Wf，Wrの車軸３
ｆ，３ｒと平行に配置され、出力軸２ｏはチエン
伝動装置４を介して後輪Wrを駆動する。 Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In FIG. 1, a three-cylinder internal combustion engine E of the present invention is mounted on a body frame F of a motorcycle.
The crankshaft 1 of this engine E and the output shaft 2o of the transmission driven by it are the axles 3 of the front and rear wheels Wf and Wr.
The output shaft 2o drives the rear wheel Wr via a chain transmission 4.
第２図及び第３図に示すように、三気筒内燃機
関Ｅは２サイクル型に構成されており、そのクラ
ンク軸１の三本のクランクピン５1，５2，５3が
同軸線上に整列させてあり、その左右両外側位置
のクランクピン５1，５2を第１及び第２クランク
ピン、中央位置のクランクピン５3を第３クラン
クピンという。 As shown in FIGS. 2 and 3, the three-cylinder internal combustion engine E is configured as a two-stroke type, and the three crank pins 5 1 , 5 2 , 5 3 of the crankshaft 1 are aligned on the same axis. The crank pins 5 1 and 5 2 at the left and right outer positions are called first and second crank pins, and the crank pin 5 3 at the center position is called a third crank pin.
クランク軸１の左端部には発電機６が、また右
端部には駆動歯車７がそれぞれ取付けられ、駆動
歯車７は変速機の入力軸２ｉ上に設けたクラツチ
９の被動歯車８と噛合する。 A generator 6 is attached to the left end of the crankshaft 1, and a drive gear 7 is attached to the right end, and the drive gear 7 meshes with a driven gear 8 of a clutch 9 provided on the input shaft 2i of the transmission.
クランク軸１は四個のベアリング１０，１０…
を介してクランクケース１１に支承される。四個
のベアリング１０，１０…は三本のクランクピン
５1，５2，５3をそれぞれ挟むように配置され、
これらベアリングを支持する隔壁によつてクラン
クケース１１の内部は第１，第２，第３クランク
ピン５1，５2，５3をそれぞれ収容する第１，第
２，第３クランク室１２1，１２2，１２3に区画
される。 The crankshaft 1 has four bearings 10, 10...
It is supported by the crankcase 11 via. The four bearings 10, 10... are arranged so as to sandwich the three crank pins 5 1 , 5 2 , 5 3 , respectively.
The interior of the crankcase 11 is divided into first, second, and third crank chambers 12 1 accommodating the first, second, and third crank pins 5 1 , 5 2 , and 5 3 , respectively, by the partition walls that support these bearings. It is divided into 12 2 and 12 3 .
第１，第２，第３クランクピン５1，５2，５3
には第１，第２，第３コンロツド１４1，１４2，
１４3及び第１，第２，第３ピストンピン１５1，
１５2，１５3を介して第１，第２，第３ピストン
１３1，１３2，１３3がそれぞれ連接され、これ
らピストン１３1，１３2，１３3が摺合する第１，
第２，第３シリンダブロツク１６1，１６2，１６
３がクランクケース１１に固着される。その際、
第１及び第２シリンダブロツク１６1，１６2は車
両の前方を向くように、また第３シリンダブロツ
ク１６3は上方を向くようにそれぞれ配置され、
かくして第１及び第２シリンダブロツク１６1，
１６2と第３シリンダブロツク１６3とは90゜のバ
ンク角を以てＶ字形に配置される。 First, second, third crank pins 5 1 , 5 2 , 5 3
The first, second and third connecting rods 14 1 , 14 2 ,
14 3 and first, second, and third piston pins 15 1 ,
The first, second , and third pistons 13 1 , 13 2 , and 13 3 are connected to each other through the pistons 15 2 and 15 3 , and the first and third pistons 13 1 , 13 2 , and 13 3 slide together.
Second and third cylinder blocks 16 1 , 16 2 , 16
3 is fixed to the crankcase 11. that time,
The first and second cylinder blocks 16 1 and 16 2 are arranged so as to face the front of the vehicle, and the third cylinder block 16 3 is arranged so as to face upward, respectively.
Thus, the first and second cylinder blocks 16 1 ,
The cylinder block 162 and the third cylinder block 163 are arranged in a V-shape with a bank angle of 90 degrees.
第１，第２，第３シリンダブロツク１６1，１
６2，１６3の先端部外周には、第１，第２，第３
シリンダヘツド１７1，１７2，１７3が螺着され、
さらにこれらシリンダヘツド１７1，１７2，１７
３の周囲に水ジヤケツト１８1，１８2，１８3を形
成する第１，第２，第３ヘツドカバー１９1，１
９2，１９3が装着される。第１，第２，第３シリ
ンダヘツド１７1，１７2，１７3には第１，第２，
第３点火栓２０1，２０2，２０3が螺着され、こ
れら点火栓２０1，２０2，２０3は、第１及び第
２シリンダヘツド１７1，１７2内の燃焼室２１1，
２１2で同時爆発を生起させるように、またこれ
らの爆発時期と第３シリンダヘツド１７2内の燃
焼室２１3での爆発時期との間にクランク角で90゜
の位相差を与えるように、図示しない点火制御装
置により制御される。 1st, 2nd, 3rd cylinder block 16 1 , 1
On the outer periphery of the tips of 6 2 and 16 3 , there are 1st, 2nd, 3rd
Cylinder heads 17 1 , 17 2 , 17 3 are screwed on,
Furthermore, these cylinder heads 17 1 , 17 2 , 17
first , second and third head covers 19 1 , 1 forming water jackets 18 1 , 18 2 , 18 3 around the
9 2 and 19 3 are installed. The first, second and third cylinder heads 17 1 , 17 2 , 17 3 have the first, second and third cylinder heads 17 1 , 17 2 and 17 3 .
Third spark plugs 20 1 , 20 2 , 20 3 are screwed onto the combustion chambers 21 1 , 20 3 in the first and second cylinder heads 17 1 , 17 2 .
21 2 to cause simultaneous explosions, and to provide a phase difference of 90° in crank angle between these explosion timings and the explosion timing in the combustion chamber 21 3 in the third cylinder head 17 2 . It is controlled by an ignition control device (not shown).
第１及び第２ピストン１３1，１３2系の往復質
量は互いに等しくされ、且つこれらの往復質量の
和と第３ピストン１３3系の往復質量とは互いに
略等しくされる。このような条件を満すために、
本発明では第１及び第２コンロツド１４1，１４2
の小端部１４1a，１４2aの外径よりも第３コンロ
ツド１４3の小端部１４3aの外径を大きくするも
ので、その際第４図に示すように、第３コンロツ
ド１４3の小端部１４3aを第３コンロツド１４3の
長手方向に長軸を向けた楕円形に形成すれば、同
一質量の円形小端部に比べ、第３ピストン１３3
の内周壁との間隙を充分広く得ることができ、し
たがつて第３クランク室１２3から第３ピストン
１３3の中空部への混合気または潤滑油の進入が
容易になつて、第３ピストン１３3の冷却が支障
なく行われる。 The reciprocating masses of the first and second piston 13 1 and 13 2 systems are made equal to each other, and the sum of these reciprocating masses and the reciprocating mass of the third piston 13 3 system are made substantially equal to each other. In order to meet these conditions,
In the present invention, the first and second connecting rods 14 1 , 14 2
The outer diameter of the small end 14 3 a of the third connecting rod 14 3 is made larger than the outer diameter of the small ends 14 1 a, 14 2 a of the third connecting rod 14 3 , as shown in FIG. If the small end 14 3 a of the piston 14 3 is formed into an elliptical shape with its long axis directed in the longitudinal direction of the third connecting rod 14 3 , the third piston 13 3 will be smaller than the circular small end of the same mass.
A sufficiently wide gap can be obtained between the inner peripheral wall of the third crank chamber 123 and the third piston 133 , so that the air-fuel mixture or lubricating oil can easily enter the hollow part of the third piston 133 from the third crank chamber 123. 13 3 cooling is carried out without any problem.
上記のようにしても、第３ピストン１３3系の
往復質量が不足する場合には、第２及び３図に示
すように第１及び第２ピストン１３1，１３2を中
空に形成する一方、、第３ピストン１３3をそれら
よりも大径に且つ中実に形成するとよい。 Even with the above method, if the reciprocating mass of the third piston 13 3 system is insufficient, the first and second pistons 13 1 and 13 2 are formed hollow as shown in FIGS. 2 and 3, while , the third piston 13 3 is preferably formed to have a larger diameter than those and to be solid.
クランク軸１は三本のクランクピン５1，５2，
５3をそれぞれ支持する各一対の第１，第２，第
３クランクウエブ２２1，２２1′；２２2，２２
2′；２２3，２２3を有し、これらにクランク軸１
の回転中心を挟んで第１，第２，第３クランクピ
ン５1，５2，５3と正反対側に配置される各一対
の第１，第２，第３バランスウエイト２３1，２
３1′；２３2，２３2′；２３3，２３3が連設され、
これらバランスウエイトは、これらの回転時の遠
心力の総和が第１及び第２ピストン１３1，１３2
系の一次慣性力と第３ピストン１３3系の一次慣
性力とにそれぞれ略釣合い、且つ質量分布が左右
対称的になるように形成される。 The crankshaft 1 has three crank pins 5 1 , 5 2 ,
Each pair of first, second , and third crank webs 22 1 , 22 1 ′; 22 2 , 22 supporting the crank webs 22 1 , 22 1 ′;
2 ′; 22 3 , 22 3 , and the crankshaft 1 is connected to these.
Each pair of first, second, and third balance weights 23 1 , 2 are disposed on opposite sides of the first, second, and third crank pins 5 1 , 5 2 , and 5 3 with respect to the center of rotation of the balance weights 23 1 , 2 .
3 1 ′; 23 2 , 23 2 ′; 23 3 , 23 3 are arranged in series,
These balance weights are such that the total centrifugal force during their rotation is the first and second pistons 13 1 , 13 2
The primary inertial force of the third piston 133 system is approximately balanced with the primary inertial force of the third piston 133 system, and the mass distribution is symmetrical.
尚、一次慣性力の大きさはそのピストン系の往
復質量とその加速度との積によつて表わされる。 The magnitude of the primary inertial force is expressed by the product of the reciprocating mass of the piston system and its acceleration.
さらに、第１，第２，第３バランスウエイト２
３1，２３1′；２３2，２３2′；２３3，２３3には第
１，第２，第３クランクピン５1，５2，５3系の
回転質量と等しい質量が、クランク軸１の回転バ
ランスのために付加される。 Furthermore, the first, second and third balance weights 2
3 1 , 23 1 ′; 23 2 , 23 2 ′; 23 3 , 23 3 has a mass equal to the rotating mass of the first, second, and third crank pins 5 1 , 5 2 , 5 3 systems, and the crankshaft 1 is added for rotational balance.
各シリンダブロツク１６1（１６2，１６3につい
ても同様）には、同列のクランク室１２1に連通
する吸気ポート２４と、そのクランク室１２1を
同列の燃焼室２１1に連通させる左右一対の掃気
ポート２５，２５と、上記燃焼室２１1を排気管
２６または２７（第１図参照）に連通させる排気
ポート２８とが設けられ、各吸気ポート２４には
混合気の逆流を阻止するリード弁２９が装着され
る。各吸気ポート２４は、第１及び第２シリンダ
ブロツク１６1，１６2と第３シリンダブロツク１
６3との間に形成されたＶ字状空間３０に開口す
るように設けられ、そして各吸気ポート２４に装
着される気化器３１とそのエアクリーナ３２とが
上記空間３０に配設される。 Each cylinder block 16 1 (the same applies to 16 2 and 16 3 ) has an intake port 24 that communicates with the crank chamber 12 1 in the same row, and a pair of left and right ports that communicate the crank chamber 12 1 with the combustion chamber 21 1 in the same row. Scavenging ports 25, 25 and an exhaust port 28 that communicates the combustion chamber 211 with an exhaust pipe 26 or 27 (see FIG. 1) are provided, and each intake port 24 is provided with a reed valve to prevent backflow of the air-fuel mixture. 29 is installed. Each intake port 24 is connected to the first and second cylinder blocks 16 1 , 16 2 and the third cylinder block 1 .
A carburetor 31 and its air cleaner 32 are disposed in the space 30 so as to open into a V-shaped space 30 formed between the intake port 24 and the intake port 24.
而して、機関Ｅの運転時には、第１シリンダブ
ロツク１６1側について言えば、ピストン１３1の
上昇行程でクランク室１２1が減圧されるので、
気化器３１で生成された混合気が吸気ポート２４
及びリード弁２９を通してクランク室１２1に吸
入され、ピストン１３1の下降行程でクランク室
１２1は加圧されるので、ここで加圧された混合
気は掃気ポート２５，２５を通して燃焼室２１1
へ充填され、そしてピストン１３1の上昇行程で
圧縮された後、点火栓２０1の放電により着火さ
れ燃焼（爆発）してピストン１３1に下降力を付
与し、このピストン１３1の下降途中から排気ポ
ート２８が開き、それから燃焼室２１1の排ガス
が排出される。第２及び第３シリンダブロツク１
６1，１６2側でも同様の作用が行われる。 When the engine E is in operation, the pressure in the crank chamber 12 1 is reduced during the upward stroke of the piston 13 1 on the first cylinder block 16 1 side.
The air-fuel mixture generated in the carburetor 31 is transferred to the intake port 24
The air-fuel mixture is sucked into the crank chamber 12 1 through the reed valve 29, and the crank chamber 12 1 is pressurized during the downward stroke of the piston 13 1 , so the pressurized air-fuel mixture flows into the combustion chamber 21 1 through the scavenging ports 25, 25.
After being compressed during the upward stroke of the piston 13 1 , it is ignited and combusted (exploded) by the discharge of the spark plug 20 1 , giving a downward force to the piston 13 1 , and from the middle of the downward movement of the piston 13 1 . The exhaust port 28 opens and exhaust gas from the combustion chamber 21 1 is exhausted from it. 2nd and 3rd cylinder block 1
A similar action is performed on the 6 1 and 16 2 sides.
この間、バランスウエイト２３1，２３1′；２
３2，２３2′；２３3，２３3群が第１及び第２シリ
ンダブロツク１６1，１６2の中心線を含む水平面
上に来たとき、それらの遠心力は第１及び第２ピ
ストン１３1，１３2系の総合一次慣性力と釣合
い、また上記バランスウエイト群が第３シリンダ
ブロツク１６3の中心線を含む垂直面上に来たと
き、それらの遠心力は第３ピストン１３1系の一
次慣性力と釣合う。 During this time, the balance weights 23 1 , 23 1 '; 2
3 2 , 23 2 ′; When the 23 3 and 23 3 groups are on a horizontal plane that includes the center lines of the first and second cylinder blocks 16 1 and 16 2 , their centrifugal force is applied to the first and second pistons 13 When the balance weight group is on a vertical plane including the center line of the third cylinder block 163 , the centrifugal force of the third piston 131 system is Balances the primary inertial force.
また、左右両側位置の第１及び第２ピストン１
３1，１３2系の一次慣性力の合力はクランク軸１
の中央部に作用し、また中央位置の第３ピストン
１３3系の一次慣性力も同じくクランク軸１の中
央部に作用し、その作用点は常に不動であり、一
方、バランスウエイト２３1，２３1′；２３2，２
３2′；２３3，２３3の質量分布は左右対称的であ
るから、これらによる遠心力も上記作用点に集中
し、その結果クランク軸１には偶力は発生しな
い。 In addition, the first and second pistons 1 located on both the left and right sides
3 1 , 13 The resultant force of the primary inertial force of the two systems is the crankshaft 1
The primary inertial force of the third piston 13 3 system at the center also acts on the center of the crankshaft 1, and its point of action is always stationary.On the other hand, the balance weights 23 1 , 23 1 ′;23 2 ,2
Since the mass distribution of 3 2 '; 23 3 and 23 3 is symmetrical, the centrifugal force caused by these is also concentrated at the point of action, and as a result, no couple is generated on the crankshaft 1.
第１，第２，第３シリンダブロツク１６1，１
６2，１６3においてピストン１３1，１３2，１３2
の行程容積及び燃焼室２１1，２１2，２１3の圧
縮比がそれぞれ等しくしてある場合、クランク室
１２1，１２2，１２3の圧縮比が相違していると、
燃焼室２１1，２１2，２１3での混合気の爆発力
に差違を来たして好ましくない。ところが、前述
のように第１及び第２ピストン１３1，１３2系の
総合往復質量と第３ピストン１３3系の往復質量
とを等しくするために、第３ピストン１３3系の
ピストンピン１５3及びコンロツド小端部１４3a
を他の系のものより大径に形成すると、その分だ
け第３クランク室１２3は有効容積が他のクラン
ク室１２1，１２2より小さくなるため、第３クラ
ンク室１２3の圧縮比は他のクランク室１２1，１
２2のそれより大きくなる。 1st, 2nd, 3rd cylinder block 16 1 , 1
Pistons 13 1 , 13 2 , 13 2 at 6 2 , 16 3
When the stroke volumes of the combustion chambers 21 1 , 21 2 , and 21 3 are the same, and the compression ratios of the crank chambers 12 1 , 12 2 , and 12 3 are different,
This is undesirable because it causes a difference in the explosive power of the mixture in the combustion chambers 21 1 , 21 2 , 21 3 . However, as mentioned above, in order to equalize the total reciprocating mass of the first and second piston 13 1 , 13 2 systems and the reciprocating mass of the third piston 13 3 system, the piston pin 15 3 of the third piston 13 3 system and conrod small end 14 3 a
If the diameter of the third crank chamber 12 3 is larger than that of other systems, the effective volume of the third crank chamber 12 3 will be smaller than that of the other crank chambers 12 1 and 12 2 , so the compression ratio of the third crank chamber 12 3 will be Other crank chambers 12 1 , 1
2 It becomes larger than that of 2 .
このようなクランク室間の圧縮比の差を是正す
るために、第３クランク室１２3の横幅（軸方向
長さ）を他のクランク室１２1，１２2の各横幅よ
り長くすると共に、第３バランスウエイト２３3，
２３3の総合厚さを他のバランスウエイト２３1，
２３1′；２３2，２３2′の各総合厚さより厚くする
ことにより、第３クランク室１２3と第３バラン
スウエイト２３2，２３3との間隙容積を他のクラ
ンク室１２1，１２3との他のバランスウエイト２
３1，２３1′；２３2，２３2′との各間隙容積より
大きくすることは有効である。このようにする
と、各クランク室とバランスウエイトとの半径方
向間隙は一定でよいから加工上有利である。 In order to correct such a difference in compression ratio between the crank chambers, the width (length in the axial direction) of the third crank chamber 12 3 is made longer than the width of each of the other crank chambers 12 1 and 12 2 , and 3 balance weight 23 3 ,
The overall thickness of 23 3 is the other balance weight 23 1 ,
23 1 ′; 23 2 , 23 2 ′, the gap volume between the third crank chamber 12 3 and the third balance weights 23 2 , 23 3 is smaller than that of the other crank chambers 12 1 , 12 3 Other balance weight 2 with
It is effective to make the space larger than the respective gap volumes between 3 1 , 23 1 ′; 23 2 and 23 2 ′. This is advantageous in processing since the radial gap between each crank chamber and the balance weight may be constant.
またこの場合、機関Ｅの横幅を可及的短くする
ために、第１及び第２クランクウエブ２２1，２
２1′；２２2，２２2′において各内側ウエブ２２1′，
２２2′を各外側ウエブ２２1，２２2より肉薄にす
ることは有効である。即ちこのようにすると、内
側ウエブ２２1′，２２2′を薄くした分だけ第１，
第２シリンダブロツク１６1，１６2間の距離を短
めることができる。 In addition, in this case, in order to make the width of the engine E as short as possible, the first and second crank webs 22 1 , 2
2 1 ′; each inner web 22 1 ′ at 22 2 , 22 2 ′;
It is advantageous to make 22 2 ' thinner than each outer web 22 1 , 22 2 . That is, by doing this , the first,
The distance between the second cylinder blocks 16 1 and 16 2 can be shortened.
さらにこの場合、薄肉の内側ウエブ２２1′，２
２2′とクランクピン５1，５2とをそれぞれ一体に
形成し、これらクランクピン５1，５2の先端部を
厚肉の外側ウエブ２２1，２２2の結合孔３３1，
３３2に圧入結合すれば、それらの圧入深さが充
分に得られるので、クランクピンの結合強度の高
い組立式クランク軸１を得る上で有効である。 Furthermore, in this case, the thin inner webs 22 1 ′, 2
2 2 ′ and crank pins 5 1 , 5 2 are integrally formed, respectively, and the tips of these crank pins 5 1 , 5 2 are inserted into the coupling holes 33 1 , 22 2 of the thick outer webs 22 1 , 22 2 .
33 2 , a sufficient press-fitting depth can be obtained, which is effective in obtaining a prefabricated crankshaft 1 with high coupling strength of the crank pin.
尚、本発明は４サイクル型三気筒内燃機関にも
適用することができ、その場合は第１及び第２シ
リンダブロツク１６1，１６2間で爆発時期をクラ
ンク角上360゜ずらせる方がよい。 The present invention can also be applied to a four-stroke three-cylinder internal combustion engine, in which case it is better to shift the explosion timing between the first and second cylinder blocks 16 1 and 16 2 by 360° above the crank angle. .
以上のように本発明によれば、クランク軸に第
１及び第２クランクピンとこれらの中間位置を占
める第３クランクピンとを同軸線上に整列して設
け、前記第１，第２及び第３クランクピンに第
１，第２及び第３コンロツドを介して第１，第２
及び第３ピストンをそれぞれ連接し、前記第１及
び第２ピストンを収容する第１及び第２シリンダ
ブロツクと、前記第３ピストンを収容する第３シ
リンダブロツクとを90゜のバンク角に開いてＶ字
状に配置し、前記第１及び第２ピストン系の総合
往復質量と前記第３ピストン系の往復質量とを略
等しくすると共に、前記第１及び第２ピストン系
の総合一次慣性力と第３ピストン系の一次慣性力
とにそれぞれ略釣合うバランスウエイトを前記ク
ランク軸に設けたので、共通のバランスウエイト
を以て第１及び第２ピストン系の一次慣性力と第
３ピストン系の一次慣性力とにそれぞれ釣合せる
ことができ、一次慣性力によるエンジンの振動を
除去することができる。 As described above, according to the present invention, the first and second crank pins and the third crank pin occupying an intermediate position therebetween are arranged on the same axis and arranged on the crankshaft, and the first, second and third crank pins are arranged on the same axis. to the first and second connecting rods via the first, second and third connecting rods.
and a third piston are connected to each other, and the first and second cylinder blocks accommodating the first and second pistons and the third cylinder block accommodating the third piston are opened at a bank angle of 90 degrees to form a V. The total reciprocating mass of the first and second piston systems is made substantially equal to the reciprocating mass of the third piston system, and the total primary inertia of the first and second piston systems is equal to the third piston system. Since balance weights are provided on the crankshaft that approximately balance the primary inertia forces of the piston systems, the common balance weights are used to balance the primary inertia forces of the first and second piston systems and the primary inertia forces of the third piston system. They can be balanced, and engine vibrations caused by primary inertia force can be eliminated.
また、前記第１及び第２ピストン系の総合往復
質量と前記第３ピストン系の往復質量とを略等し
くするために、前記第１及び第２コンロツドの小
端部の外径よりも第３コンロツドの小端部の外径
を大きくしたので、第３コンロツドの小端部の単
なる形状変更により所期の往復質量の釣合いを容
易に得ることができる。 Furthermore, in order to make the total reciprocating mass of the first and second piston systems substantially equal to the reciprocating mass of the third piston system, the outer diameter of the third conrod is smaller than the outer diameter of the small end of the first and second conrod. Since the outer diameter of the small end of the third connecting rod is increased, the desired reciprocating mass balance can be easily obtained by simply changing the shape of the small end of the third connecting rod.
また、全ピストン系の一次慣性力の合力の作用
点は常にピストン軸の中央部の点にあつて変動す
ることはないから、前記バランスウエイトの遠心
力を上記一点に集中させることによりクランク軸
に不釣合い偶力が発生することを防止することが
でき、不釣合い偶力によるエンジンの振動をも回
避することができ、しかも従来の三気筒内燃機関
に比べ格別構造が複雑になることもない。 In addition, since the point of action of the resultant force of the primary inertial forces of the entire piston system is always at the central point of the piston shaft and does not change, by concentrating the centrifugal force of the balance weight on the one point, it is applied to the crankshaft. It is possible to prevent the occurrence of an unbalanced couple, it is also possible to avoid engine vibration due to the unbalanced couple, and the structure is not particularly complicated compared to a conventional three-cylinder internal combustion engine.
尚、本発明において第１及び第２ピストン系の
往復質量W1＋W2と第３ピストン系の往復質量
W3とを略等しくするということは、振動防止上
許容される範囲でW1＋W2とW3とが互いに近接
している場合を含むもので、具体的にはW3がW1
＋W2の75〜110％の範囲に収まれば実際上差支え
ない。 In addition, in the present invention, the reciprocating mass W 1 + W 2 of the first and second piston systems and the reciprocating mass of the third piston system
Making W 3 substantially equal includes the case where W 1 + W 2 and W 3 are close to each other within the permissible range for vibration prevention. Specifically, W 3 is equal to W 1
There is no problem in practice as long as it falls within the range of 75 to 110% of +W 2 .
第１図は本発明の一実施例に基づく三気筒内燃
機関を搭載したオートバイの側面図、第２図は上
記機関の要部縦断平面図、第３図は第２図の―
線断面図、第４図は上記機関の第３コンロツド
小端部の変形例を示す部分側面図である。
Ｅ……三気筒内燃機関、１……クランク軸、５
１〜５3……第１〜第３クランクピン、１１……ク
ランクケース、１２1〜１２3……第１〜第３クラ
ンク室、１３1〜１３3……第１〜第３ピストン、
１４1〜１４3……第１〜第３コンロツド、１４
1a，１４2a，１４3a……小端部、１５1〜１５3…
…第１〜第３ピストンピン、１６1〜１６3……第
１〜第３シリンダブロツク、２２1，２２1′；２
２2，２２2′；２２3，２２3……第１，第２，第３
クランクウエブ、２３1，２３1′；２３2，２３
2′；２３3，２３3……第１，第２，第３バランス
ウエイト。
FIG. 1 is a side view of a motorcycle equipped with a three-cylinder internal combustion engine according to an embodiment of the present invention, FIG. 2 is a longitudinal sectional plan view of the main parts of the engine, and FIG.
A line sectional view, and FIG. 4 is a partial side view showing a modification of the third connecting rod small end of the engine. E... Three-cylinder internal combustion engine, 1... Crankshaft, 5
1 to 5 3 ... first to third crank pin, 11 ... crank case, 12 1 to 12 3 ... first to third crank chamber, 13 1 to 13 3 ... first to third piston,
14 1 ~ 14 3 ... 1st ~ 3rd conrod, 14
1 a, 14 2 a, 14 3 a...small end, 15 1 to 15 3 ...
...first to third piston pins, 16 1 to 16 3 ...first to third cylinder blocks, 22 1 , 22 1 '; 2
2 2 , 22 2 ′; 22 3 , 22 3 ...first, second, third
Crank web, 23 1 , 23 1 '; 23 2 , 23
2 ′; 23 3 , 23 3 ...first, second, and third balance weights.
Claims (1)
れらの中間位置を占める第３クランクピンとを同
軸線上に整列して設け、これら第１，第２及び第
３クランクピンに第１，第２及び第３コンロツド
を介して第１，第２及び第３ピストンをそれぞれ
連接し、前記第１及び第２ピストンを収容する第
１及び第２シリンダブロツクと、前記第３ピスト
ンを収容する第３ブロツクとを90°のバンク角に
開いてＶ字状に配置し、前記第１及び第２ピスト
ン系の総合往復質量と前記第３ピストン系の往復
質量とが略等しくなるように前記第１及び第２コ
ンロツドの小端部の外径よりも第３コンロツドの
小端部の外径を大きくし、前記第１及び第２ピス
トン系の総合一次慣性力と前記第３ピストン系の
一次慣性力とにそれぞれ略釣合うバランスウエイ
トを前記クランク軸に設けてなる、三気筒内燃機
関。 ２ 特許請求の範囲第１項記載のものにおいて、
前記第３コンロツドの小端部を、該コンロツドの
長手方向を長軸方向とする楕円形に形成した、三
気筒内燃機関。[Scope of Claims] 1. First and second crank pins and a third crank pin occupying an intermediate position therebetween are arranged coaxially on the crankshaft, and a first crank pin is arranged on the first, second and third crank pins. , first, second and third pistons are connected via second and third connecting rods, respectively, and first and second cylinder blocks housing the first and second pistons and housing the third piston. The third block is arranged in a V-shape with a bank angle of 90°, and the third block is arranged in a V-shape with a bank angle of 90°, and the first and second piston systems are arranged so that the total reciprocating mass of the first and second piston systems is approximately equal to the reciprocating mass of the third piston system. The outer diameter of the small end of the third connecting rod is made larger than the outer diameter of the small end of the first and second connecting rods, and the total primary inertia of the first and second piston systems and the primary inertia of the third piston system are A three-cylinder internal combustion engine, wherein the crankshaft is provided with balance weights that substantially balance the respective forces. 2. In what is stated in claim 1,
A three-cylinder internal combustion engine, wherein the small end of the third connecting rod is formed into an elliptical shape with the longitudinal direction of the third connecting rod as the major axis direction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16161782A JPS5950247A (en) | 1982-09-17 | 1982-09-17 | Internal-combustion engine having three cylinders |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16161782A JPS5950247A (en) | 1982-09-17 | 1982-09-17 | Internal-combustion engine having three cylinders |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5950247A JPS5950247A (en) | 1984-03-23 |
| JPS6314212B2 true JPS6314212B2 (en) | 1988-03-30 |
Family
ID=15738573
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16161782A Granted JPS5950247A (en) | 1982-09-17 | 1982-09-17 | Internal-combustion engine having three cylinders |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5950247A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB8608237D0 (en) * | 1986-04-04 | 1986-05-08 | Collins Motor Corp Ltd | Reciprocatory positive displacement machines |
-
1982
- 1982-09-17 JP JP16161782A patent/JPS5950247A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5950247A (en) | 1984-03-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8757123B2 (en) | Balancing an opposed-piston, opposed-cylinder engine | |
| US5044333A (en) | Balancing arrangement for internal combustion engine | |
| JPS6131332B2 (en) | ||
| US4517933A (en) | Crank shaft of V-type internal-combustion engine | |
| JPH0561485B2 (en) | ||
| US4685428A (en) | Multi-cylinder internal combustion engine | |
| JPH0315045B2 (en) | ||
| JP3942693B2 (en) | Oil separator structure of internal combustion engine | |
| JPH09324651A (en) | Crankcase supercharged v-engine | |
| US5189993A (en) | In-line three cylinder combustion engine | |
| JPS6314212B2 (en) | ||
| US1881027A (en) | Reciprocating engine | |
| JP2870654B2 (en) | Parallel 2-cylinder 4-cycle engine | |
| JPS5946359A (en) | V-type 2-cycle internal-combustion engine for autobicycle | |
| JPH0222201B2 (en) | ||
| JPS6314213B2 (en) | ||
| JPS6352216B2 (en) | ||
| JPS6344986B2 (en) | ||
| JPH0315044B2 (en) | ||
| JPS5946324A (en) | V-type internal-comustion engine for motorcycle | |
| US20040211383A1 (en) | Secondary balancer of vertical engine of outboard motor | |
| US4974449A (en) | Method for balancing the crankshaft in an uneven degree firing engine | |
| JPH049465Y2 (en) | ||
| US1703096A (en) | burtnett | |
| JPH09166126A (en) | Crank construction for in-parallel multicylinder engine |