JPH0350247Y2

JPH0350247Y2 -

Info

Publication number: JPH0350247Y2
Application number: JP1984049581U
Authority: JP
Priority date: 1984-04-06
Filing date: 1984-04-06
Publication date: 1991-10-28
Also published as: JPS60162202U

Description

【考案の詳細な説明】この考案は、４バルブ型の４サイクルエンジン
のバルブ作動装置に関する。[Detailed Description of the Invention] This invention relates to a valve operating device for a four-valve type four-cycle engine.

４サイクルエンジンで、一つの気筒に二つの吸
気弁と二つの排気弁を設けた４バルブ型のエンジ
ンは、吸気弁及び排気弁の開口面積が大きくでき
て、吸排気効率を向上させることができるので高
性能エンジンにできる。しかし、吸気弁及び排気
弁が各々２つ必要になるだけでなく、直打式のも
のではカムが２つづつ必要になり、ロツカーアー
ム式のものでは、ロツカーアームを二又にして
も、バルブ隙間の調節が、各バルブ毎に必要にな
り、軽量化が困難で、複雑な構造になり、バルブ
の隙間調節にも手間がかかる不都合がある。 A 4-cycle engine with two intake valves and two exhaust valves per cylinder is a 4-valve type engine, which allows the opening areas of the intake and exhaust valves to be large, improving intake and exhaust efficiency. This makes it possible to create a high-performance engine. However, not only are two intake valves and two exhaust valves required, but the direct drive type also requires two cams, and the Rocker arm type requires two valve gaps even if the Rocker arm is bifurcated. Adjustment is required for each valve, making it difficult to reduce weight, resulting in a complicated structure, and requiring time and effort to adjust the gap between the valves.

この考案は、かかる点に鑑み改善したもので、
以下本考案を図面に示す実施例について説明す
る。 This idea is an improvement based on these points.
Embodiments of the present invention shown in the drawings will be described below.

吸気弁及び排気弁は、傘形のバルブ１が一対設
けられており、バルブスプリング２で上方に付勢
して閉じるようにしてあつて、バルブスプリング
２に抗して押下げると開くようになつている。左
右に伸びるアーム片３は、両端を左右のバルブ１
の上端に掛けわたすようにしてあつて、バルブ１
との当り面は、球面で当るようにしてある。摺動
片４は、断面が逆凹字状にできていて、中央をア
ーム片３の中央に乗せる。この当り面も球面にし
てある。摺動片４は、シリンダヘツド５に設けた
ガイド用の溝６に摺動自在に挿入して傾かないよ
うにしてある。摺動片４の上面には、隙間調節用
のシム７が嵌め合わせてあり、シム７の上面を、
カムシヤフト８のカム９の回転によつて押圧でき
るようにしてある。 The intake valve and the exhaust valve are provided with a pair of umbrella-shaped valves 1, which are urged upward by a valve spring 2 to close them, and are opened by pushing down against the valve spring 2. ing. The arm piece 3 that extends left and right has both ends attached to the left and right valves 1.
Valve 1
The contact surface is made to contact with a spherical surface. The sliding piece 4 has an inverted concave cross section, and its center is placed on the center of the arm piece 3. This contact surface is also spherical. The sliding piece 4 is slidably inserted into a guide groove 6 provided in the cylinder head 5 to prevent it from tilting. A shim 7 for adjusting the gap is fitted on the top surface of the sliding piece 4, and the top surface of the shim 7 is
It can be pressed by rotation of a cam 9 of a camshaft 8.

しかして、カムシヤフト８のカム９は、回転に
よつて、摺動片４の上面のシム７の面を押圧す
る。摺動片４はこの押圧によつて、シリンダヘツ
ド５の溝６に沿つて下方に摺動する。摺動片４の
摺動と共に、アーム片３も押され、両端で左右の
バルブ１をバネ２に抗して押下げて開く。アーム
片３は、中央を摺動片４に当ててあるので、左右
のバルブ１を均等に押下げる。左右のバランス
は、球面接触部で保ち、アンバランスを吸収でき
る。又、アーム片３とバルブ１は、球面当りでピ
ツチ誤差、傾き等を吸収する。しかもバルブ１と
カム９の隙間は、一つのシム７の交換で調節でき
る。 Thus, the cam 9 of the camshaft 8 presses the surface of the shim 7 on the upper surface of the sliding piece 4 by rotation. Due to this pressure, the sliding piece 4 slides downward along the groove 6 of the cylinder head 5. As the sliding piece 4 slides, the arm piece 3 is also pushed, and the left and right valves 1 are pushed down at both ends against the spring 2 and opened. Since the center of the arm piece 3 is placed against the sliding piece 4, the left and right valves 1 are pushed down equally. The balance between the left and right sides is maintained by the spherical contact area, and unbalance can be absorbed. Furthermore, the arm piece 3 and the valve 1 absorb pitch errors, inclinations, etc. by contacting the spherical surface. Furthermore, the gap between the valve 1 and the cam 9 can be adjusted by replacing one shim 7.

以上説明したように、この考案は、左右一対の
吸気又は排気用の傘形のバルブの上端に左右に伸
びるアーム片の両端を掛けわたし、バルブの上端
とアーム片とを球面によつて当接させるととも
に、シリンダヘツドの溝に摺動自在に挿入した断
面逆凹字形の摺動片をアーム片の中央に球面係合
させ、その摺動片の上面をカムシヤフトのカムの
回転によつて押圧して一対の傘形のバルブを開閉
するようにしたので、左右一対のバルブの隙間の
調整を摺動片に設けたシムを交換するだけで一カ
所で行なうことができ、また点検も簡単にでき
る。さらに摺動片は左右のバルブの邪魔になるこ
ともなく小型にでき、バルブ間の間隙が狭い小型
のエンジンにも使用できて軽量にできる。しかも
上端とアーム片間およびアーム片と摺動片間はそ
れぞれ球面係合するようにしてあるので、アーム
片が摺動片に対して傾斜可能で左右一対のバルブ
のクリアランスの不均一を吸収させることができ
る。尚、バルブ上端にタペツトを用いることがあ
るが、その場合は、アーム片はタペツトを押すこ
とになることは云うまでもない。 As explained above, this invention involves hanging both ends of arm pieces extending left and right over the upper ends of a pair of left and right umbrella-shaped intake or exhaust valves, and bringing the upper ends of the valves and the arm pieces into contact with the spherical surface. At the same time, a sliding piece having an inverted concave cross section that is slidably inserted into a groove in the cylinder head is brought into spherical engagement with the center of the arm piece, and the upper surface of the sliding piece is pressed by the rotation of the cam of the camshaft. Since the pair of umbrella-shaped valves are opened and closed using the lever, the gap between the pair of left and right valves can be adjusted in one place by simply replacing the shims provided on the sliding piece, and inspection is also easy. . Furthermore, the sliding piece can be made smaller without getting in the way of the left and right valves, and can be used in small engines with narrow gaps between valves, making it lightweight. Moreover, since the upper end and the arm piece and between the arm piece and the sliding piece are designed to engage each other spherically, the arm piece can be tilted with respect to the sliding piece, thereby absorbing uneven clearance between the left and right pair of valves. be able to. Note that a tappet may be used at the upper end of the valve, and in that case, it goes without saying that the arm piece will push against the tappet.

[Brief explanation of the drawing]

図は本考案の一実施例を示し、第１図は平面
図、第２図は第１図Ａ−Ａ矢視正面図、第３図は
第１図Ｂ−Ｂ矢視側面図である。１……バルブ、３……アーム片、４……摺動
片、５……シリンダヘツド、６……溝、８……カ
ムシヤフト、９……カム。 The drawings show an embodiment of the present invention, in which FIG. 1 is a plan view, FIG. 2 is a front view taken along the line AA in FIG. 1, and FIG. 3 is a side view taken along the line BB in FIG. 1. 1... Valve, 3... Arm piece, 4... Sliding piece, 5... Cylinder head, 6... Groove, 8... Camshaft, 9... Cam.

Claims

[Scope of utility model registration request]

Hang both ends of the arm pieces extending left and right over the upper ends of the pair of left and right intake or exhaust umbrella-shaped valves,
The upper end of the valve and the arm piece are brought into contact with the spherical surface, and a sliding piece with an inverted concave cross section that is slidably inserted into the groove of the cylinder head is spherically engaged with the center of the arm piece, and the sliding A valve operating device for a four-cycle engine, characterized in that the upper surface of the piece is pressed by rotation of a cam of a camshaft to open and close a pair of umbrella-shaped valves.