JPH09250626A - Internal oil feeding type hollow cam shaft - Google Patents
Internal oil feeding type hollow cam shaftInfo
- Publication number
- JPH09250626A JPH09250626A JP5804096A JP5804096A JPH09250626A JP H09250626 A JPH09250626 A JP H09250626A JP 5804096 A JP5804096 A JP 5804096A JP 5804096 A JP5804096 A JP 5804096A JP H09250626 A JPH09250626 A JP H09250626A
- Authority
- JP
- Japan
- Prior art keywords
- cam
- oil
- oil supply
- supply hole
- nose
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/02—Valve drive
- F01L1/04—Valve drive by means of cams, camshafts, cam discs, eccentrics or the like
- F01L1/047—Camshafts
- F01L2001/0475—Hollow camshafts
Landscapes
- Valve-Gear Or Valve Arrangements (AREA)
- Lubrication Of Internal Combustion Engines (AREA)
- Gears, Cams (AREA)
- General Details Of Gearings (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】この発明は、カムシャフト、
特に自動車用エンジン等の内燃機関に使用されかつカム
面に潤滑油を供給する給油孔を有する内部給油式中空カ
ムシャフトに関する。The present invention relates to a camshaft,
More particularly, the present invention relates to an internal lubrication type hollow camshaft used for an internal combustion engine such as an automobile engine and having an oil supply hole for supplying lubricating oil to a cam surface.
【０００２】[0002]
【従来の技術】自動車のエンジン性能の改善に伴い、種
々の荷重が加わるカムシャフトに対して近時一層厳しい
摺動条件が要求されてきている。一般に、カムの焼き付
きを防止するカム摺動面への給油には下記の条件が求め
られる。2. Description of the Related Art With the improvement of engine performance of automobiles, camshafts subjected to various loads have recently been required to have more severe sliding conditions. Generally, the following conditions are required for lubricating a cam sliding surface for preventing cam seizure.
【０００３】（１） 供給する給油量が少ないこと。(1) The amount of oil to be supplied is small.
【０００４】（２） 潤滑油を供給するポンプを小さい
動力で駆動できること。(2) A pump for supplying lubricating oil can be driven with small power.
【０００５】（３） 高負荷かつ高回転数で運転できる
こと。(3) Operable under high load and high rotational speed.
【０００６】（４） 摺動面の潤滑効率が高いこと。(4) The lubrication efficiency of the sliding surface is high.
【０００７】（５） 必要な摺動部にのみ給油できかつ
潤滑油の飛散量が少ないこと。(5) The lubricating oil can be supplied only to necessary sliding parts and the amount of lubricating oil scattered is small.
【０００８】自動車用エンジンに多用される鋳鉄製のカ
ムシャフトは、高硬度を要求されるカム面を鋳造時に白
銑化するチルド法と鋳造後に表面硬化させる方法によっ
て主として製造される。また、カムの摺動部に対する給
油方法は、カムが潤滑油に浸るようにカムの周りに油溜
まりを形成して給油を行う外部給油方式と、カムシャフ
トの中心を中空にし、鋳造後にカムの摺動面に給油孔を
機械加工で穿孔し、カムの内部を通る潤滑油を摺動面に
導く内部給油方式に大別される。外部給油方式は、十分
な潤滑に多量の潤滑油を必要とし、給油に比較的大きな
容量のポンプが必要となる。このため、エンジンの高速
回転時に油の掻き上げ抵抗及びポンプ駆動による動力ロ
スが顕著に増し、負荷を駆動すべきエンジンの出力が損
なわれる。また、カムにより掻き上げた油が飛散する
上、高速回転時にカム摺動面に対する潤滑状態の制御が
困難となり、十分な潤滑効果を得ることができない。[0008] Cast iron camshafts, which are frequently used in automobile engines, are mainly manufactured by a chilled method of turning a cam surface, which requires high hardness, into white iron during casting, and a method of surface hardening after casting. In addition, the lubrication method for the sliding portion of the cam includes an external oiling method in which an oil reservoir is formed around the cam so that the cam is immersed in the lubricating oil to supply oil, and a method in which the center of the camshaft is hollow and the cam is cast after casting. It is roughly classified into an internal lubrication system in which a lubrication hole is drilled in the sliding surface by machining to guide the lubricating oil passing through the inside of the cam to the sliding surface. The external lubrication system requires a large amount of lubrication oil for sufficient lubrication, and a relatively large capacity pump is required for lubrication. For this reason, when the engine is rotating at high speed, the resistance to scraping up the oil and the power loss due to the driving of the pump are significantly increased, and the output of the engine to drive the load is impaired. In addition, the oil scraped up by the cam is scattered, and it is difficult to control the lubrication state of the cam sliding surface during high-speed rotation, so that a sufficient lubrication effect cannot be obtained.
【０００９】これに対し、内部給油方式は、ベースサー
クル部以外のカム摺動に最適な位置では硬度が高いた
め、機械加工により給油孔を形成できない。このため、
やむを得ず比較的硬度が低く加工の容易なベースサーク
ル部上に給油孔を機械加工で形成せざるを得ず、高速時
に焼き付きの発生しやすいカムのノーズ（鼻面）近傍へ
の給油が困難となる。また、小さな直径で給油孔をカム
に形成することが困難なため、給油孔の直径は大きくな
り、このため少量の潤滑油を高い油圧でカムの摺動部に
供給することができなかった。On the other hand, in the internal lubrication system, since the hardness is high at a position other than the base circle portion which is optimal for cam sliding, the lubrication hole cannot be formed by machining. For this reason,
Inevitably, an oil supply hole must be formed by machining on a base circle portion having relatively low hardness and easy processing, and it becomes difficult to lubricate the vicinity of a nose (nose surface) of a cam where seizure easily occurs at high speed. Further, since it is difficult to form an oil supply hole in the cam with a small diameter, the diameter of the oil supply hole becomes large, so that a small amount of lubricating oil cannot be supplied to the sliding portion of the cam with high oil pressure.
【００１０】[0010]
【発明が解決しようとする課題】例えば、図９〜図１１
に示すように、外部給油方式では、カム５０に隣接して
配置されたバルブリフタ５１に潤滑油が供給され、バル
ブリフタ５１の外面に付着する潤滑油５４は底面５２に
流動する。図１０及び図１１に示すように、カム５０が
反時計方向に回転すると、底面５２に付着した潤滑油が
カム５０のノーズ面５３によって掻き取られる。このた
め、カム５０が連続して高速回転するとバルブリフタ５
１の底面５２に十分な量の潤滑油５４が供給されず、カ
ム５０とバルブリフタ５１との間で焼き付きを発生す
る。この焼き付きを防止するため、カム５０が十分に浸
漬するだけの量の潤滑油を供給しなければならず、高速
回転で潤滑油の油掻き抵抗が顕著に増大した。Problems to be Solved by the Invention For example, FIGS.
As shown in (2), in the external lubrication method, lubricating oil is supplied to a valve lifter 51 disposed adjacent to the cam 50, and lubricating oil 54 attached to the outer surface of the valve lifter 51 flows to the bottom surface 52. As shown in FIGS. 10 and 11, when the cam 50 rotates counterclockwise, the lubricating oil attached to the bottom surface 52 is scraped off by the nose surface 53 of the cam 50. Therefore, when the cam 50 continuously rotates at a high speed, the valve lifter 5
A sufficient amount of the lubricating oil 54 is not supplied to the bottom surface 52 of the first unit 1, and seizure occurs between the cam 50 and the valve lifter 51. In order to prevent this seizure, it was necessary to supply a sufficient amount of lubricating oil so that the cam 50 was sufficiently immersed, and the oil scraping resistance of the lubricating oil was significantly increased at high speed rotation.
【００１１】また、内部給油方式では、機械加工の容易
なカムのベースサークル面に給油孔を形成する場合があ
るが、ベースサークル面に給油孔を形成しても、給油孔
から供給される潤滑油がノーズ面と底面との間にまで供
給されず焼き付きを発生する。このように、外部給油方
式及び内部給油方式のいずれも、エンジンの回転数及び
焼き付きの発生する焼き付き限界荷重を増加することが
できず運転能力が制限される欠点がある。In the internal lubrication system, an oil supply hole may be formed on the base circle surface of the cam which is easily machined. However, even if the oil supply hole is formed on the base circle surface, the lubrication supplied from the oil supply hole may be formed. Oil is not supplied between the nose surface and the bottom surface, causing seizure. As described above, both the external refueling method and the internal refueling method have a disadvantage that the engine speed and the seizing limit load at which seizure occurs cannot be increased, and the operating capacity is limited.
【００１２】この発明は、稼動時の焼き付き限界荷重を
増加できる内部給油式中空カムシャフトを提供すること
を目的とする。An object of the present invention is to provide an internal lubrication type hollow camshaft capable of increasing the seizure limit load during operation.
【００１３】[0013]
【課題を解決するための手段】この発明による内部給油
式中空カムシャフトは、軸部と、軸部に一体に形成され
たカム部とを備えている。カム部は、ベースサークル面
と、ベースサークル面から径方向に突出する凸面とを含
むカム面を備えている。軸部及びカム部に軸方向に形成
された配油孔に対してほぼ直角にカム部に形成され給油
孔の一端を配油孔に連結し、給油孔の他端をカム面上で
開放して、配油孔及び給油孔を通じてカム面に潤滑油を
供給する。凸面に形成されたノーズ面の中央とカムの中
心を通る中心線に対して２０゜〜３５゜の範囲内にカム
面の中間部を形成して、中間部に給油孔の他端を接続す
る。An internally refueling hollow camshaft according to the present invention includes a shaft portion and a cam portion integrally formed with the shaft portion. The cam portion has a cam surface including a base circle surface and a convex surface projecting radially from the base circle surface. One end of the oil supply hole formed in the cam portion is formed substantially perpendicular to the oil distribution hole formed in the shaft portion and the cam portion in the axial direction, and one end of the oil supply hole is connected to the oil distribution hole, and the other end of the oil supply hole is opened on the cam surface. Thus, lubricating oil is supplied to the cam surface through the oil distribution hole and the oil supply hole. An intermediate portion of the cam surface is formed within a range of 20 ° to 35 ° with respect to a center line passing through the center of the nose surface formed on the convex surface and the center of the cam, and the other end of the oil supply hole is connected to the intermediate portion. .
【００１４】一端が配油孔に連結された給油孔の他端は
ノーズ面が従動子に至る前のフランク面とショルダ面と
の間に接続されるため、給油孔からカム面上に供給され
る潤滑油は、ノーズ面が従動子に当接する直前に従動子
との間に油膜を形成する。このため、カム面の回転に伴
いノーズ面とノーズ面に続くカム面上に油膜が形成さ
れ、ノーズ面付近での油切れを防止することができる。The other end of the oil supply hole, one end of which is connected to the oil distribution hole, is connected between the flank surface and the shoulder surface before the nose surface reaches the follower. The lubricating oil forms an oil film with the follower immediately before the nose surface contacts the follower. For this reason, an oil film is formed on the nose surface and the cam surface following the nose surface with the rotation of the cam surface, and it is possible to prevent running out of oil near the nose surface.
【００１５】[0015]
【発明の実施の形態】以下、この発明による内部給油式
中空カムシャフトの実施形態を図１〜図８について説明
する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a hollow camshaft of an internal oil supply type according to the present invention will be described with reference to FIGS.
【００１６】図１及び図２に示すように、この発明によ
る内部給油式中空カムシャフト１は、軸部２と、軸部２
に一体に形成されたカム部３とを備えている。軸部２及
びカム部３には配油孔４が軸方向に形成されると共に、
配油孔４に対してほぼ直角に給油孔５がカム部３に形成
される。図２に示すように、カム部３は、ベースサーク
ル面７と、ベースサークル面７から径方向に突出する凸
面８とを含むカム面６を備えている。給油孔５の一端５
ａは配油孔４に連結され、他端５ｂは、カム面６上の第
１フランク面１４と第１ショルダ面１５との間に接続さ
れる。カム面６は、従動子１０に接触する回転方向に、
ベースサークル面７と、第１ランプ面１３と、第１フラ
ンク面１４と、第１ショルダ面１５と、ノーズ面１２
と、第２ショルダ面１６と、第２フランク面１７と、第
２ランプ面１８とを備え、第２ランプ面１８はベースサ
ークル面７に連結される。中間部１１は、カム面６のベ
ースサークル面７に連続するランプ面１３、１８と、フ
ランク面１４、１７と、ショルダ面１５、１６とを含
み、ショルダ面１５、１６は凸面８に形成されたノーズ
面１２に連続する。第１ランプ面１３、第１フランク面
１４及び第１ショルダ面１５は、ベースサークル面７及
びノーズ面１２を通る中心線に対して第２ランプ面１
８、第２ショルダ面１６及び第２フランク面１７と対称
である。第１ランプ面１３、第１フランク面１４及び第
１ショルダ面１５はカム面６上の中間部１１を構成し、
中間部１１に給油孔５の他端５ｂが接続される。８ａは
ベースサークル面７とランプ面１３との境界に形成され
る接触開始点である。カム面６の中間部１１は、凸面８
に形成されたノーズ面１２の中央とカムの中心を通る中
心線に対して２０゜〜３５゜の範囲内に形成される。As shown in FIGS. 1 and 2, an internally refueling hollow camshaft 1 according to the present invention comprises a shaft 2 and a shaft 2.
And a cam portion 3 formed integrally with the camshaft. Oil distribution holes 4 are formed in the shaft portion 2 and the cam portion 3 in the axial direction.
An oil supply hole 5 is formed in the cam portion 3 substantially at right angles to the oil distribution hole 4. As shown in FIG. 2, the cam portion 3 includes a cam surface 6 including a base circle surface 7 and a convex surface 8 projecting radially from the base circle surface 7. One end 5 of oil supply hole 5
a is connected to the oil distribution hole 4, and the other end 5 b is connected between the first flank surface 14 and the first shoulder surface 15 on the cam surface 6. The cam surface 6 rotates in the rotation direction in contact with the follower 10,
Base circle surface 7, first ramp surface 13, first flank surface 14, first shoulder surface 15, nose surface 12
, A second shoulder surface 16, a second flank surface 17, and a second ramp surface 18, and the second ramp surface 18 is connected to the base circle surface 7. The intermediate portion 11 includes ramp surfaces 13 and 18 continuous with the base circle surface 7 of the cam surface 6, flank surfaces 14 and 17, and shoulder surfaces 15 and 16. The shoulder surfaces 15 and 16 are formed on the convex surface 8. Nose surface 12. The first ramp surface 13, the first flank surface 14, and the first shoulder surface 15 are aligned with the center line passing through the base circle surface 7 and the nose surface 12.
8, the second shoulder surface 16 and the second flank surface 17 are symmetrical. The first ramp surface 13, the first flank surface 14, and the first shoulder surface 15 constitute an intermediate portion 11 on the cam surface 6,
The other end 5 b of the oil supply hole 5 is connected to the intermediate portion 11. 8a is a contact start point formed at the boundary between the base circle surface 7 and the ramp surface 13. The intermediate portion 11 of the cam surface 6 has a convex surface 8
Is formed within a range of 20 ° to 35 ° with respect to a center line passing through the center of the nose surface 12 and the center of the cam.
【００１７】図３に示すように、従動子１０はカム面６
に当接するほぼ平坦な当接面１０ａを有し、カム３が反
時計方向に回転すると、カム面６の中間部１１が従動子
１０に対面した後、従動子１０は回転するカム面６に当
接して直線運動を行い、配油孔４及び給油孔５を通じて
カム面６に潤滑油２０が供給される。図３に示すよう
に、給油孔５の他端５ｂはノーズ面１２が従動子１０に
至る前の第１フランク面１４と第１ショルダ面１５との
間に接続されるため、給油孔５からカム面６上に供給さ
れる潤滑油２０は、ノーズ面１２が従動子１０に当接す
る直前に従動子１０との間に油膜を形成し、適量の潤滑
油２０が摺動面に保持される。このため、カム面６の回
転に伴いノーズ面１２とノーズ面１２に続くカム面６上
に油膜が形成され、ノーズ面１２付近での油切れを防止
することができる。As shown in FIG. 3, the follower 10 is
When the cam 3 rotates counterclockwise, the intermediate portion 11 of the cam surface 6 faces the follower 10, and the follower 10 contacts the rotating cam surface 6. The lubricating oil 20 is supplied to the cam surface 6 through the oil distribution hole 4 and the oil supply hole 5 by making a linear motion in contact. As shown in FIG. 3, the other end 5 b of the oil supply hole 5 is connected between the first flank surface 14 and the first shoulder surface 15 before the nose surface 12 reaches the follower 10. The lubricating oil 20 supplied on the cam surface 6 forms an oil film with the follower 10 immediately before the nose surface 12 abuts on the follower 10, and an appropriate amount of the lubricating oil 20 is held on the sliding surface. . For this reason, an oil film is formed on the nose surface 12 and the cam surface 6 following the nose surface 12 with the rotation of the cam surface 6, and it is possible to prevent running out of oil near the nose surface 12.
【００１８】図４はカムシャフト１が時計方向に回転す
る実施形態を示す。給油孔５の他端が第２ショルダ面１
６と第２フランク面１７との間に接続される。第２ショ
ルダ面１６と第２フランク面１７との間に接続された給
油孔５を通じて潤滑油２０が供給される。カムシャフト
１の稼動の際に、カム面６が時計方向に回転すると、ノ
ーズ面１２が従動子１０に当接する直前に従動子１０と
の間に油膜を形成する。潤滑油２０は、第２ショルダ面
１６に付着し、ノーズ面１２、第１ショルダ面１５、第
１フランク面１４及び第１ランプ面１３上に延ばされ
る。このため、カム面６の回転に伴いノーズ面１２とノ
ーズ面１２に続くカム面６上に油膜が形成され、ノーズ
面１２付近での油切れを防止することができる。FIG. 4 shows an embodiment in which the camshaft 1 rotates clockwise. The other end of the oil supply hole 5 is the second shoulder surface 1
6 and the second flank surface 17. Lubricating oil 20 is supplied through oil supply hole 5 connected between second shoulder surface 16 and second flank surface 17. When the cam surface 6 rotates clockwise during operation of the camshaft 1, an oil film is formed between the cam surface 1 and the follower 10 immediately before the nose surface 12 contacts the follower 10. The lubricating oil 20 adheres to the second shoulder surface 16 and extends on the nose surface 12, the first shoulder surface 15, the first flank surface 14, and the first ramp surface 13. For this reason, an oil film is formed on the nose surface 12 and the cam surface 6 following the nose surface 12 with the rotation of the cam surface 6, and it is possible to prevent running out of oil near the nose surface 12.
【００１９】図５はこの発明によるカムシャフト１の焼
き付き性の評価を行うカム試験機を示す。カム試験機３
０は、球面ジョイント３１、３２にそれぞれ揺動可能に
接続されたタペット保持ロッド３３及び軸受保持ロッド
３４と、タペット保持ロッド３３の先端部に固定された
タペット試片３５と、タペット保持ロッド３３の先端部
の上面に当接して軸受保持ロッド３４に固定されたロー
ラ軸受３６と、軸受支持ロッド３４の先端部の上面に固
定された軸部３７ａを有するエンジンバルブ３７と、エ
ンジンバルブ３７を支持するホルダ３８と、軸受支持ロ
ッド３４の上面に当接するばね受３９とホルダ３８との
間に配置されかつエンジンバルブ３７の軸部３７ａを軸
受支持ロッド３４に対して押圧するバルブスプリング４
０とを備えている。タペット試片３５の下方にはカム試
片４１が回転可能の保持される。ホルダ３８とバルブス
プリング４０との間及びホルダ３８と支持テーブル４３
との間に調整用スペーサ４４、４５を配置し、ホルダ３
８をボルト４６で締結してバルブスプリング４０の圧縮
力が調整される。タペット保持ロッド３３の一部に歪ゲ
ージ４７を取付けて、タペット保持ロッド３３の歪を測
定して潤滑状態を調べる。カム試片４１の回転時にタペ
ット試片３５に作用する摩擦力の大きさは歪ゲージ４７
により測定される。自動車の動弁系を模擬したカム試験
機３０を用いて、カムの耐焼き付き性の評価を行った。FIG. 5 shows a cam tester for evaluating the seizure of the camshaft 1 according to the present invention. Cam testing machine 3
Reference numeral 0 denotes a tappet holding rod 33 and a bearing holding rod 34 that are swingably connected to the spherical joints 31 and 32, a tappet sample 35 fixed to the tip of the tappet holding rod 33, and a tappet holding rod 33, respectively. A roller bearing 36 fixed to the bearing holding rod 34 in contact with the upper surface of the distal end portion, an engine valve 37 having a shaft portion 37 a fixed to the upper surface of the distal end portion of the bearing support rod 34, and supports the engine valve 37. A valve spring 4 disposed between the holder 38 and a spring receiver 39 abutting on the upper surface of the bearing support rod 34 and the holder 38 and pressing the shaft portion 37a of the engine valve 37 against the bearing support rod 34.
0. A cam sample 41 is rotatably held below the tappet sample 35. Between the holder 38 and the valve spring 40 and between the holder 38 and the support table 43
And adjusting spacers 44 and 45 between them, and the holder 3
8 is tightened with bolts 46 to adjust the compression force of the valve spring 40. The strain gauge 47 is attached to a part of the tappet holding rod 33, and the strain of the tappet holding rod 33 is measured to check the lubrication state. The magnitude of the frictional force acting on the tappet specimen 35 when the cam specimen 41 rotates is determined by the strain gauge 47.
Is measured by Using a cam tester 30 simulating a valve train of an automobile, the seizure resistance of the cam was evaluated.
【００２０】歪ゲージ４７では、焼き付き発生の有無の
他に、焼き付き発生時の接触荷重を測定し、接触荷重か
ら焼付の発生する限界荷重を知ることができる。また、
カム試片４１の焼き付き性を試験するとき、潤滑に適し
た給油孔５の形成位置を決定することができる。In the strain gauge 47, in addition to the presence or absence of seizure, the contact load at the time of seizure is measured, and the critical load at which seizure occurs can be known from the contact load. Also,
When testing the seizure of the cam specimen 41, the position of the oil supply hole 5 suitable for lubrication can be determined.
【００２１】図６は耐焼き付き性試験の設定条件を示
す。即ち、潤滑油温度を約６０〜１００℃、回転速度を
６００〜１０００ｒｐｍ、バルブスプリング４０の初期
設定荷重を５００〜１６００Ｎ（ニュートン）の範囲内
で変化させる。使用したカム試片はチル鋳鉄、従動子は
焼結金属、潤滑油は８ＯＮ、潤滑油供給速度は毎分２１
９グラム、回転数は６００〜１０００ｒｐｍ、潤滑油の
動作温度は６０〜１００℃である。FIG. 6 shows the setting conditions of the seizure resistance test. That is, the lubricating oil temperature is changed in the range of about 60 to 100 ° C., the rotation speed is set in the range of 600 to 1000 rpm, and the initial load of the valve spring 40 is changed in the range of 500 to 1600 N (Newton). The used cam specimen was chill cast iron, the follower was sintered metal, the lubricating oil was 8 ON, and the lubricating oil supply rate was 21 per minute.
9g, rotation speed is 600 ~ 1000rpm, lubricating oil operating temperature is 60 ~ 100 ° C.
【００２２】ベースサークル面７、第１フランク面１
４、第１ショルダ面１５、ノーズ面１２、第２ショルダ
面１６、第２フランク面１７及びベースサークル面７の
各位置に給油孔５をそれぞれ形成したカム試片４１を用
意し、各カム試片４１に対し最大接触荷重を徐々に増加
させてカム荷重試験を行った。カム荷重試験の結果を図
７に示す。図７に示すように、ベースサークル面７に給
油孔５を設けたカムでは３.７２ｋＮ（キロニュート
ン）の最大接触荷重で焼き付きが発生するのに対し、第
１フランク面１４及び第１ショルダ面１５に給油孔５を
設けたカムでは、装置の限界である４ｋＮを越えても焼
き付きは発生しなかった。最大接触荷重を受けるノーズ
面１２又は潤滑油２０の切れる第１ショルダ面１６若し
くは第２フランク面１７に給油孔５を設けるとよいと思
われたが、前記カム試験では、潤滑油２０を掻き始める
ノーズ面１２の手前の第１フランク面１４及び第１ショ
ルダ面１５に給油孔５を設けると、焼き付き限界荷重を
増加でき、耐焼き付性を改善できることが解った。最大
接触荷重を受けるノーズ面１２によって従動子１０の当
接面１０ａから潤滑油が掻かれ、給油孔５がないと、ノ
ーズ面１２を過ぎたところで油膜切れが起きやすいと考
えられ、ノーズ面１２近傍では最大接触荷重の下で油膜
切れが生じて焼付が発生する。また、図８に示すよう
に、ノーズ面１２に給油孔５５を形成すると、給油孔５
５から流出する潤滑油５４に大きな逆方向の圧力が加え
られ、十分な量の潤滑油が供給されず、また、潤滑油が
ノーズ面１２の両側から外部へ逃げ易いため、油膜切れ
が発生する。そこで、この発明では、給油孔５から潤滑
油２０を中間部１１に供給するのが、油膜切れ性、油膜
保持性の両面で潤滑上最も適した位置と結論する。Base circle surface 7, first flank surface 1
4. A cam specimen 41 in which the lubrication holes 5 are formed at respective positions of the first shoulder surface 15, the nose surface 12, the second shoulder surface 16, the second flank surface 17 and the base circle surface 7 is prepared. A cam load test was performed by gradually increasing the maximum contact load on the piece 41. FIG. 7 shows the results of the cam load test. As shown in FIG. 7, in the cam provided with the oil supply hole 5 in the base circle surface 7, seizure occurs at a maximum contact load of 3.72 kN (kilo Newton), whereas the first flank surface 14 and the first shoulder surface In the case of the cam provided with the oil supply hole 5 in 15, no burn-in occurred even if the limit of the device was exceeded, 4 kN. It was thought that the oil supply hole 5 should be provided in the nose surface 12 receiving the maximum contact load or the first shoulder surface 16 or the second flank surface 17 where the lubricating oil 20 can be cut. However, in the cam test, the lubricating oil 20 starts to be scraped. It has been found that when the oil supply holes 5 are provided in the first flank surface 14 and the first shoulder surface 15 before the nose surface 12, the seizure limit load can be increased and the seizure resistance can be improved. If the lubricating oil is scraped from the contact surface 10a of the follower 10 by the nose surface 12 receiving the maximum contact load, and if there is no oil supply hole 5, it is considered that the oil film is likely to be cut off past the nose surface 12 and the nose surface 12 In the vicinity, under the maximum contact load, the oil film breaks and seizure occurs. Further, as shown in FIG. 8, when the oil supply hole 55 is formed in the nose surface 12, the oil supply hole 5 is formed.
A large reverse pressure is applied to the lubricating oil 54 flowing out of the nozzle 5, and a sufficient amount of the lubricating oil is not supplied. Further, since the lubricating oil easily escapes from both sides of the nose surface 12 to the outside, an oil film break occurs. . Therefore, in the present invention, it is concluded that supplying the lubricating oil 20 to the intermediate portion 11 from the oil supply hole 5 is the most suitable position for lubrication in both the oil film breaking property and the oil film holding property.
【００２３】本実施形態では下記の作用効果が得られ
る。In the present embodiment, the following operation and effect can be obtained.
【００２４】（１） 接触開始点８ａとベースサークル
面７との間の中間部１１に給油孔５を接続して焼き付き
限界荷重を増加することができる。(1) The oil supply hole 5 is connected to the intermediate portion 11 between the contact start point 8a and the base circle surface 7 to increase the seizure limit load.
【００２５】（２） 外部供給方式及びベースサークル
面７に給油孔５を設ける従来の内部給油方式に較べて、
給油量を大幅に低減することができる。(2) Compared with the external supply system and the conventional internal supply system in which the oil supply hole 5 is provided in the base circle surface 7,
The amount of refueling can be greatly reduced.
【００２６】（３） カム面６に適量の潤滑油２０を供
給してカム部３を円滑に回転し、エンジンの動力損失を
抑制することができる。(3) An appropriate amount of lubricating oil 20 is supplied to the cam surface 6 to rotate the cam portion 3 smoothly, thereby suppressing power loss of the engine.
【００２７】（４） カム面６と従動子１０との間に供
給された潤滑油２０を摺動部に確実に案内し、有効に潤
滑作用を発生させると共に、潤滑油２０の飛散量を減少
することができる。(4) The lubricating oil 20 supplied between the cam surface 6 and the follower 10 is reliably guided to the sliding portion to effectively generate a lubricating action and reduce the amount of the lubricating oil 20 scattered. can do.
【００２８】（５） カム面６と従動子１０との間の摺
動部に対する潤滑効果が高く耐摩耗性と耐焼き付き性を
向上することができ、高荷重かつ高回転のエンジンのカ
ム部及び従動部を比較的安価な材料で形成することがで
きる。(5) The lubricating effect on the sliding portion between the cam surface 6 and the follower 10 is high, and the abrasion resistance and seizure resistance can be improved. The follower can be made of a relatively inexpensive material.
【００２９】（６） カムの回転によって給油孔５内の
潤滑油に遠心力が与えられるため、比較的低いポンプ吐
出圧力でも十分な給油圧力を得ることができる。(6) A centrifugal force is applied to the lubricating oil in the oil supply hole 5 by the rotation of the cam, so that a sufficient oil supply pressure can be obtained even at a relatively low pump discharge pressure.
【００３０】この発明の実施形態は前記の例に限定され
ず、変更が可能である。従動子を平坦面を有するタペッ
トとして示したが、カムによりロッカーアームを従動子
として駆動してもよい。The embodiment of the present invention is not limited to the above example, but can be modified. Although the follower is shown as a tappet having a flat surface, the rocker arm may be driven as a follower by a cam.
【００３１】[0031]
【発明の効果】カムの摺動部に効果的に潤滑油を減少し
た量で供給できかつ焼き付き限界荷重を増加することが
できるため、カムの摺動部への潤滑油の供給量を減少す
ると共に、高トルクで高回転のエンジンを実現でき、エ
ンジンの性能を向上して寿命を延長することができる。The lubricating oil can be effectively supplied to the sliding portion of the cam in a reduced amount and the seizure limit load can be increased, so that the amount of lubricating oil supplied to the sliding portion of the cam can be reduced. At the same time, a high-torque, high-torque engine can be realized, the engine performance can be improved, and the life can be extended.
【図１】 この発明による内部給油式中空カムシャフト
の斜視図FIG. 1 is a perspective view of an internally refueling hollow camshaft according to the present invention.
【図２】 図１に示すカム部の正面図FIG. 2 is a front view of the cam section shown in FIG. 1;
【図３】 反時計方向に回転するこの発明による内部給
油式中空カムシャフトのカム部の正面図FIG. 3 is a front view of the cam portion of the internally lubricated hollow camshaft according to the present invention, which rotates counterclockwise.
【図４】 時計方向に回転するこの発明による内部給油
式中空カムシャフトのカム部の正面図FIG. 4 is a front view of the cam portion of the internally refueled hollow camshaft according to the present invention, which rotates clockwise.
【図５】 カムシャフトの焼き付き性の評価を行うカム
試験機の断面図FIG. 5 is a cross-sectional view of a cam tester for evaluating the seizure of a camshaft.
【図６】 耐焼き付き性試験の設定条件を示すグラフFIG. 6 is a graph showing setting conditions of a seizure resistance test.
【図７】 カム面の給油孔位置と焼き付き発生の限界荷
重との関係を示すグラフFIG. 7 is a graph showing a relationship between a position of an oil supply hole on a cam surface and a limit load at which seizure occurs.
【図８】 潤滑油の供給孔をノーズ面に形成した例を示
す正面図FIG. 8 is a front view showing an example in which a lubricating oil supply hole is formed on a nose surface.
【図９】 外部給油方式のカムが従動子に当接する前の
状態を示す正面図FIG. 9 is a front view showing a state before the cam of the external refueling system contacts the follower.
【図１０】 外部給油方式のカムが従動子に当接した後
の状態を示す正面図FIG. 10 is a front view showing a state after the cam of the external refueling system has contacted the follower.
【図１１】 外部給油方式のカムが従動子に当接した後
カムの後続面が当接する状態を示す正面図FIG. 11 is a front view showing a state in which the trailing surface of the cam comes into contact after the cam of the external refueling system comes into contact with the follower;
１・・内部給油式中空カムシャフト、 ２・・軸部、
３・・カム部、 ４・・配油孔、 ５・・給油孔、 ５
ａ・・一端、 ５ｂ・・他端、 ６・・カム面、 ７・
・ベースサークル面、 ８・・凸面、 ８ａ・・接触開
始点、 １０・・従動子、 １１・・中間部、 １２・
・ノーズ面、 １３・・第１ランプ面、１４・・第１フ
ランク面、 １５・・第１ショルダ面、 １６・・第２
ショルダ面、 １７・・第２フランク面、 １８・・第
２ランプ面、1. Internal hollow camshaft, 2. Shaft,
3 ··· Cam part, 4 · · Oil distribution hole, 5 · · Oil supply hole, 5
a ... one end, 5b ... the other end, 6. cam surface, 7.
· Base circle surface, 8 ··· Convex surface, 8a · · · Contact start point, 10 · · Follower, 11 · · · Middle part, 12 ·
-Nose surface, 13-1st ramp surface, 14-1st flank surface, 15-1st shoulder surface, 16-2nd
Shoulder surface, 17 ··· 2nd flank surface, 18 ··· 2nd ramp surface,
Claims (1)
とを備え、カム部は、ベースサークル面と、ベースサー
クル面から径方向に突出する凸面とを含むカム面を備
え、軸部及びカム部に軸方向に形成された配油孔に対し
てほぼ直角にカム部に形成され給油孔の一端を配油孔に
連結し、給油孔の他端をカム面上で開放して、配油孔及
び給油孔を通じてカム面に潤滑油を供給する内部給油式
中空カムシャフトにおいて、 凸面に形成されたノーズ面の中央とカムの中心を通る中
心線に対して２０゜〜３５゜の範囲内にカム面の中間部
を形成して、中間部に給油孔の他端を接続したことを特
徴とする内部給油式中空カムシャフト。A shaft portion and a cam portion formed integrally with the shaft portion, wherein the cam portion includes a cam surface including a base circle surface and a convex surface projecting radially from the base circle surface; One end of the oil supply hole formed in the cam portion is formed substantially perpendicular to the oil distribution hole formed in the shaft portion and the cam portion in the axial direction, and one end of the oil supply hole is connected to the oil distribution hole, and the other end of the oil supply hole is opened on the cam surface. In the internal oil supply type hollow camshaft that supplies lubricating oil to the cam surface through the oil distribution hole and the oil supply hole, the center line passing through the center of the cam and the center of the nose surface formed on the convex surface and the center of the cam. Wherein an intermediate portion of the cam surface is formed within the range, and the other end of the oil supply hole is connected to the intermediate portion.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5804096A JPH09250626A (en) | 1996-03-14 | 1996-03-14 | Internal oil feeding type hollow cam shaft |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5804096A JPH09250626A (en) | 1996-03-14 | 1996-03-14 | Internal oil feeding type hollow cam shaft |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH09250626A true JPH09250626A (en) | 1997-09-22 |
Family
ID=13072832
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5804096A Pending JPH09250626A (en) | 1996-03-14 | 1996-03-14 | Internal oil feeding type hollow cam shaft |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH09250626A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010116822A (en) * | 2008-11-12 | 2010-05-27 | Toyota Motor Corp | Lubricating device for valve train |
| JP2012013168A (en) * | 2010-07-01 | 2012-01-19 | Toyota Motor Corp | Lubricant supply structure |
| JP2018115681A (en) * | 2017-01-16 | 2018-07-26 | 住友重機械工業株式会社 | Speed reduction device and method of heat-treating rotary body |
| CN113958685A (en) * | 2021-11-08 | 2022-01-21 | 重庆市巨亮机械制造有限责任公司 | Powder metallurgy camshaft end combination |
-
1996
- 1996-03-14 JP JP5804096A patent/JPH09250626A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010116822A (en) * | 2008-11-12 | 2010-05-27 | Toyota Motor Corp | Lubricating device for valve train |
| JP2012013168A (en) * | 2010-07-01 | 2012-01-19 | Toyota Motor Corp | Lubricant supply structure |
| JP2018115681A (en) * | 2017-01-16 | 2018-07-26 | 住友重機械工業株式会社 | Speed reduction device and method of heat-treating rotary body |
| CN113958685A (en) * | 2021-11-08 | 2022-01-21 | 重庆市巨亮机械制造有限责任公司 | Powder metallurgy camshaft end combination |
| CN113958685B (en) * | 2021-11-08 | 2024-03-12 | 重庆市巨亮机械制造有限责任公司 | Powder metallurgy camshaft end combination |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5054440A (en) | Cam follower device for valve driving mechanism in engine | |
| US20040042698A1 (en) | Bearing device | |
| US5127374A (en) | Valve lifter | |
| US5178107A (en) | Valve lifter | |
| JPH1030419A (en) | Bearing device for internal combustion engine | |
| JP3003403B2 (en) | Bearing structure of internal combustion engine | |
| JPH09250626A (en) | Internal oil feeding type hollow cam shaft | |
| US7299777B2 (en) | Fastening of a bearing bolt to a roller tappet | |
| KR19990082841A (en) | Crankshaft Bearing for Large motor | |
| JPH11247845A (en) | Bearing device for roller support | |
| JPH07317899A (en) | Piston pin for internal combustion engine and machining method therefor | |
| US5325826A (en) | Journal bearing oil diverter | |
| EP1307635A1 (en) | Improvements in cam contacting devices | |
| EP1818554A3 (en) | Performance judgment method for dynamic pressure bearing and dynamic pressure bearing | |
| JP3780156B2 (en) | Rocker arm | |
| US20030185471A1 (en) | Sliding bearing | |
| JPH08233070A (en) | Roller for cam follower | |
| JPH09195724A (en) | Tappet roller bearing | |
| JPH074809U (en) | Lubrication structure of valve train | |
| JPH0660708U (en) | Camshaft | |
| JP2010203270A (en) | Lubricating device of double-link type internal combustion engine | |
| JPH03286109A (en) | Valve system of four-cycle engine | |
| US7219638B2 (en) | System comprising a cam and a cam follower element and use of such a system | |
| KR100521210B1 (en) | valve tip part of engine valve | |
| JPH1182494A (en) | Hydrostatic bearing device |