JP2000054811A - Cam follower having sheet metal rocker arm and its assembling method - Google Patents
Cam follower having sheet metal rocker arm and its assembling methodInfo
- Publication number
- JP2000054811A JP2000054811A JP10225661A JP22566198A JP2000054811A JP 2000054811 A JP2000054811 A JP 2000054811A JP 10225661 A JP10225661 A JP 10225661A JP 22566198 A JP22566198 A JP 22566198A JP 2000054811 A JP2000054811 A JP 2000054811A
- Authority
- JP
- Japan
- Prior art keywords
- side walls
- pivot
- pair
- rocker arm
- sheet metal
- 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
Landscapes
- Valve-Gear Or Valve Arrangements (AREA)
- Lubrication Of Internal Combustion Engines (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】この発明は、エンジンの動弁
機構に組み込み、カムシャフトの回転を弁体（吸気弁及
び排気弁）の往復運動に変換する為のロッカーアームの
うち、金属板にプレス加工を施す事により造る板金製ロ
ッカーアームを備えたカムフォロアとその組立方法の改
良に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rocker arm for converting the rotation of a camshaft into a reciprocating motion of a valve body (an intake valve and an exhaust valve). BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cam follower having a rocker arm made of sheet metal, which is manufactured by performing processing, and an improvement of an assembling method thereof.
【０００２】[0002]
【従来の技術】レシプロエンジン（往復ピストンエンジ
ン）には、一部の２サイクルエンジンを除き、クランク
シャフトの回転と同期して開閉する吸気弁及び排気弁を
設けている。この様なレシプロエンジンでは、上記クラ
ンクシャフトの回転と同期して（４サイクルエンジンの
場合には１／２の回転速度で）回転するカムシャフトの
動きを、ロッカーアームにより、上記吸気弁及び排気弁
に伝達し、これら吸気弁及び排気弁を軸方向に亙り往復
運動させる。2. Description of the Related Art A reciprocating engine (reciprocating piston engine) is provided with an intake valve and an exhaust valve which open and close in synchronization with rotation of a crankshaft, except for a part of a two-cycle engine. In such a reciprocating engine, the movement of the camshaft that rotates in synchronization with the rotation of the crankshaft (at a rotation speed of 1/2 in the case of a four-cycle engine) is controlled by the rocker arm using the intake valve and the exhaust valve. To reciprocate the intake and exhaust valves in the axial direction.
【０００３】従来は、この様なエンジンの動弁機構に組
み込むロッカーアームを、鋳造品（鋳鉄品或はアルミニ
ウムダイキャスト品）とする事が一般的であった。とこ
ろが、鋳造品は重量が嵩んだり（鋳鉄品の場合）、或は
十分に強度を確保する為には容積が嵩張る（アルミニウ
ムダイキャスト品の場合）。又、一般的にはロストワッ
クス法により造る為、製造コストが嵩む事も避けられな
い。この為に近年、鋼板等の金属板にプレス加工を施す
事により上記ロッカーアームを造る事が考えられ、一部
で実施されている。Conventionally, a rocker arm to be incorporated in such a valve operating mechanism of an engine is generally a cast product (a cast iron product or an aluminum die-cast product). However, the cast product is heavy (in the case of a cast iron product), or has a large volume in order to secure sufficient strength (in the case of an aluminum die-cast product). In addition, since it is generally manufactured by the lost wax method, it is inevitable that the production cost increases. For this reason, in recent years, it has been considered to manufacture the rocker arm by pressing a metal plate such as a steel plate, and this has been partially implemented.
【０００４】この様な事情で考えられた板金製ロッカー
アームとして従来から、例えば特開平３−１７２５０６
号公報に記載されたものがある。図３〜６は、この公報
に記載された、板金製ロッカーアームを示している。こ
の板金製ロッカーアームを造る場合には、先ず、材料と
なる金属板（例えば厚さが２〜４mm程度の炭素鋼板）を
プレス加工で打ち抜く事により、図３（Ａ）に示す様な
形状を有する素板（ブランク）１を形成する。As a rocker arm made of sheet metal considered under such circumstances, a conventional rocker arm is disclosed in, for example, Japanese Patent Application Laid-Open No. 3-172506.
Is described in Japanese Patent Application Publication No. 3 to 6 show a sheet metal rocker arm described in this publication. When manufacturing this sheet metal rocker arm, first, a metal plate (for example, a carbon steel plate having a thickness of about 2 to 4 mm) as a material is punched out by press working to obtain a shape as shown in FIG. A blank (blank) 1 is formed.
【０００５】次いで、この素板１にプレスによる曲げ加
工を施して、図４に示す様な第一中間素材２を形成す
る。この第一中間素材２は、互いに平行な１対の側壁部
３、３と、これら両側壁部３、３の幅方向端縁同士を連
結する連結部４と、これら両側壁部３、３と連結部４と
により三方を囲まれる空間の中間部に設けられたローラ
収容凹部５と、上記連結部４の中間部一端寄り部分に設
けられた、球状凹面であるピボット部６とを有する。Next, the blank 1 is subjected to bending by a press to form a first intermediate material 2 as shown in FIG. The first intermediate material 2 includes a pair of side walls 3, 3 parallel to each other, a connecting portion 4 for connecting the width direction edges of the side walls 3, 3, and the side walls 3, 3. It has a roller housing concave portion 5 provided at an intermediate portion of a space surrounded by the connecting portion 4 on three sides, and a pivot portion 6 provided as a spherical concave surface provided at a portion near one end of the intermediate portion of the connecting portion 4.
【０００６】次いで、上述の様な第一中間素材２を構成
する上記連結部４の一部で上記ローラ収容凹部５に対応
する部分に、図５に示す様な、上記各側壁部３、３と平
行な側から見た場合に鼓形の透孔７を形成して、第二中
間素材８とする。この第二中間素材８の一部で、この透
孔７を幅方向｛図５（Ａ）の上下方向｝両側から挟む位
置には、それぞれ円弧状の突出部９、９が、互いの突縁
同士を対向させた状態で存在する。又、上記透孔７は、
中央部の幅Ｗ7 を両端寄り部分の幅に比較して狭くして
いる。Next, a part of the connecting part 4 constituting the first intermediate material 2 as described above, which corresponds to the roller accommodating recess 5, is provided with the side wall parts 3, 3 as shown in FIG. When viewed from a side parallel to the above, the hourglass-shaped through hole 7 is formed to be a second intermediate material 8. At portions of the second intermediate material 8 which sandwich the through hole 7 from both sides in the width direction {vertical direction in FIG. 5 (A)}, arc-shaped projections 9, 9 are formed at the protruding edges of each other. They exist in a state where they face each other. The through hole 7 is
It is narrower than the width W 7 of the central portion to the width near both ends portions.
【０００７】上述の様な第二中間素材８には、続く工程
で、上記透孔７の周囲部分に、バーリング加工及び扱き
加工を施す事により、図６に示す様な第三中間素材１０
とする。この第三中間素材１０は、上記透孔７部分を、
上記各側壁部３、３と平行な側から見た場合に矩形の開
口１１とすると共に、上記連結部４の他端部分の形状を
整えて、吸気弁或は排気弁を構成する弁体の基端部を突
き当てる為のバルブ係合部１２としたものである。上述
の様な第三中間素材１０には、続く工程で、上記両側壁
部３、３の互いに整合する位置に、カムと係合するロー
ラを回転自在に支持する為の支持軸の両端部を支持する
為の円形の通孔を形成し、板金製ロッカーアームとして
完成する。[0007] In the subsequent step, the surrounding portion of the through hole 7 is subjected to burring and handling to the second intermediate material 8 as shown in FIG.
And This third intermediate material 10 has
When viewed from the side parallel to each of the side walls 3, 3, a rectangular opening 11 is formed, and the shape of the other end of the connecting portion 4 is adjusted to form a valve element constituting an intake valve or an exhaust valve. This is a valve engaging portion 12 for abutting the base end. In the subsequent step, the both ends of the support shaft for rotatably supporting the rollers engaged with the cams are provided on the third intermediate material 10 as described above at the positions where the side walls 3 and 3 are aligned with each other. A circular through-hole for supporting is formed, and a rocker arm made of sheet metal is completed.
【０００８】この様な板金製ロッカーアームに上記ロー
ラを組み付けるには、上記両側壁部３、３同士の間にロ
ーラを配置した状態で、このローラ及び上記１対の通孔
に枢軸を挿通する。その後、この枢軸の両端部をこれら
両通孔の内周面に向けかしめ広げる事により、この枢軸
を上記１対の側壁部３、３同士の間に掛け渡す状態で固
定する。この状態で上記ローラは、上記１対の側壁部
３、３同士の間の前記ローラ収容凹部５に、回転自在に
支持される。そして、この様な板金製ロッカーアームを
備えたカムフォロアをエンジンに組み付けた状態では、
上記ローラの外周面をカムの外周面に当接させ、前記ピ
ボット部６にラッシュアジャスタの先端部を突き当て、
前記バルブ係合部１２に吸気弁又は排気弁の基端部を突
き当てる。In order to assemble the roller to such a rocker arm made of sheet metal, a pivot is inserted through the roller and the pair of through holes with the roller disposed between the side walls 3,3. . After that, both ends of the pivot are crimped toward the inner peripheral surfaces of the two through holes to fix the pivot in a state of being bridged between the pair of side walls 3. In this state, the roller is rotatably supported by the roller accommodating recess 5 between the pair of side walls 3. And, with the cam follower equipped with such a sheet metal rocker arm attached to the engine,
The outer peripheral surface of the roller is brought into contact with the outer peripheral surface of the cam, and the tip of the lash adjuster is abutted against the pivot portion 6,
A base end of an intake valve or an exhaust valve is abutted against the valve engaging portion 12.
【０００９】[0009]
【発明が解決しようとする課題】板金製ロッカーアーム
は、鋳造品のロッカーアームに比べて優れた靱性を有す
る反面、力の作用方向によっては弾性変形し易い場合が
ある。即ち、ローラ支持用の枢軸の両端部を掛け渡す為
の１対の側壁部３、３はそれぞれ平板状である為、これ
ら各側壁部３、３に対し直角方向の力が加わると、比較
的容易に弾性変形する。一方、これら各側壁部３、３に
上記枢軸の両端部を結合固定すべく、この枢軸の両端部
をこれら両通孔の内周面に向けかしめ広げると、上記各
側壁部３、３の一部でこれら各通孔を形成した部分に、
互いに近づく方向の力が加わる。そして、この力に基づ
いて上記各側壁部３、３が弾性変形する。A rocker arm made of sheet metal has excellent toughness as compared with a rocker arm of a cast product, but may be easily elastically deformed depending on the direction of force application. That is, since the pair of side walls 3, 3 for bridging both ends of the roller supporting pivot are flat, respectively, when a force in a direction perpendicular to these side walls 3, 3 is applied, the side walls 3, 3 are relatively flat. Easily elastically deforms. On the other hand, when both ends of the pivot are crimped toward the inner peripheral surfaces of the through holes in order to connect and fix both ends of the pivot to the side walls 3, 3, one end of each of the side walls 3, 3 is formed. In the part where these through holes were formed in the part,
Forces approaching each other are applied. Then, the side walls 3 are elastically deformed based on this force.
【００１０】従来の板金製ロッカーアームの場合には、
上記枢軸の両端部をかしめ広げる以前の状態で、上記１
対の側壁部３、３を互いに平行にしていた。この為、上
記枢軸の両端部を上記各通孔の内周面に向けかしめ広げ
た状態では、上記１対の側壁部３、３同士が互いに非平
行になる。従って、これら各側壁部３、３の内側面（互
いに対向する側面）と、上記枢軸の中間部に回転自在に
支持したローラの軸方向両端面とが非平行になる。この
結果、上記各側壁部３、３の内側面とローラの軸方向両
端面とが均等に広い面積で接触せず、極く狭い部分で接
触したり、上記各側壁部３、３の端縁とローラの軸方向
両端面とが接触する、所謂エッヂ当たりを生じる。In the case of a conventional rocker arm made of sheet metal,
Before swaging both ends of the pivot,
The pair of side walls 3, 3 were parallel to each other. Therefore, in a state in which both ends of the pivot are crimped toward the inner peripheral surfaces of the through holes, the pair of side walls 3, 3 are not parallel to each other. Therefore, the inner side surfaces (side surfaces facing each other) of each of the side wall portions 3 and 3 are not parallel to both axial end surfaces of the roller rotatably supported at the intermediate portion of the pivot. As a result, the inner side surfaces of the side walls 3 and 3 and the axial end surfaces of the rollers do not uniformly contact with each other over a wide area, but contact with a very narrow portion. Contact between the roller and both end surfaces in the axial direction of the roller.
【００１１】この様な状態では、上記各側壁部３、３の
内側面とローラの軸方向両端面との間に、これら両面同
士の摩擦を低減させる為の油膜が十分に形成されにくく
なる。そして、ローラの回転に要する抵抗が増大した
り、或はローラ若しくは板金製ロッカーアームの摩耗量
が増大する為、好ましくない。本発明の板金製ロッカー
アームを備えたカムフォロアとその組立方法は、この様
な不都合を解消すべく発明したものである。In such a state, it is difficult to sufficiently form an oil film between the inner surface of each of the side walls 3 and the both end surfaces in the axial direction of the roller to reduce friction between these two surfaces. This is not preferable because the resistance required for the rotation of the roller increases or the amount of wear of the roller or the rocker arm made of sheet metal increases. The cam follower having the rocker arm made of sheet metal and the method of assembling the same according to the present invention have been invented in order to solve such inconveniences.
【００１２】[0012]
【課題を解決するための手段】本発明の板金製ロッカー
アームを備えたカムフォロアとその組立方法のうち、請
求項１に記載した板金製ロッカーアームを備えたカムフ
ォロアは、前述した従来の板金製ロッカーアームを備え
たカムフォロアと同様に、金属板により造られ、互いに
ほぼ平行な１対の側壁部と、これら両側壁部同士を連結
する連結部とを備えた板金製ロッカーアームと、これら
両側壁部の互いに整合する位置に形成した１対の通孔同
士の間に掛け渡した状態で、その両端部をこれら両通孔
の内周面に向けかしめ広げる事により、上記１対の側壁
部同士の間に掛け渡す状態で固定した枢軸と、この枢軸
の中間部周囲に回転自在に支持したローラとから構成す
る。特に、本発明の板金製ロッカーアームを備えたカム
フォロアに於いては、上記枢軸の両端部をかしめ広げる
以前の状態で、上記１対の側壁部のうちの上記各通孔を
形成した部分の間隔を、上記枢軸の両端部をかしめ広げ
た状態でのこの部分の間隔よりも広くしておく事によ
り、この枢軸の両端部をかしめ広げた状態で上記１対の
側壁部同士を平行にする。According to the cam follower having the rocker arm made of sheet metal of the present invention and the method of assembling the same, the cam follower having the rocker arm made of sheet metal according to claim 1 is a conventional rocker made of sheet metal as described above. Similar to a cam follower provided with an arm, a sheet metal rocker arm made of a metal plate and provided with a pair of substantially parallel side walls and a connecting portion connecting the both side walls to each other; In a state of being bridged between a pair of through-holes formed at positions matching with each other, the opposite end portions are swaged toward the inner peripheral surfaces of both of the through-holes, thereby forming the pair of side wall portions. It comprises a pivot fixed in a state of being bridged therebetween, and a roller rotatably supported around an intermediate portion of the pivot. In particular, in the cam follower provided with the rocker arm made of sheet metal of the present invention, before the both ends of the pivot are swaged apart, the distance between the portions where the through holes are formed in the pair of side walls is formed. Is wider than the distance between the two ends of the pivot when the two ends are swaged, so that the pair of side walls are parallel to each other with both ends of the pivot swaged.
【００１３】又、請求項２に記載した、板金製ロッカー
アームを備えたカムフォロアの組立方法は、やはり前述
した板金製ロッカーアームを備えたカムフォロアの組立
方法と同様に、金属板により、１対の側壁部とこれら両
側壁部同士を連結する連結部とを備え、これら両側壁部
の互いに整合する位置に１対の通孔を形成した板金製ロ
ッカーアームを造る。これと共に、上記両側壁部同士の
間にローラを配置した状態で、このローラ及び上記１対
の通孔に枢軸を挿通した後、この枢軸の両端部をこれら
両通孔の内周面に向けかしめ広げる事により、この枢軸
を上記１対の側壁部同士の間に掛け渡す状態で固定す
る。特に、本発明の板金製ロッカーアームを備えたカム
フォロアの組立方法に於いては、上記枢軸の両端部をか
しめ広げる以前の状態で、上記１対の側壁部のうちの上
記各通孔を形成した部分の間隔を、上記枢軸の両端部を
かしめ広げた状態でのこの部分の間隔よりも広くしてお
く。そして、この枢軸の両端部をかしめ広げる事に伴っ
て上記１対の側壁部のうちの上記各通孔を形成した部分
の間隔を狭くする事により、上記１対の側壁部同士を平
行にする。According to a second aspect of the present invention, there is provided a method of assembling a cam follower having a rocker arm made of sheet metal, similarly to the above-described method of assembling a cam follower having a rocker arm made of sheet metal, using a pair of metal plates. A rocker arm made of sheet metal is provided which includes a side wall portion and a connecting portion for connecting the both side wall portions, and a pair of through holes are formed at positions where the side wall portions match each other. At the same time, after inserting a pivot into the roller and the pair of through holes in a state in which the roller is disposed between the both side wall portions, both ends of the pivot are directed toward the inner peripheral surfaces of the two through holes. By caulking and widening, the pivot is fixed between the pair of side wall portions. In particular, in the method of assembling a cam follower having a rocker arm made of sheet metal according to the present invention, the through-holes of the pair of side wall portions are formed before both ends of the pivot are swaged. The interval between the portions is set to be wider than the interval between the portions when both ends of the pivot are swaged. Then, by caulking and expanding both ends of the pivot, the interval between the portions where the through holes are formed in the pair of side walls is narrowed, so that the pair of side walls are parallel to each other. .
【００１４】[0014]
【作用】上述の様な構成を有する本発明の板金製ロッカ
ーアームを備えたカムフォロアとその組立方法によれ
ば、板金製ロッカーアームとローラと枢軸とを組み合わ
せ、この枢軸の両端部をこの板金製ロッカーアームを構
成する１対の側壁部に結合固定した状態で、これら両側
壁部と上記ローラの軸方向両端面とを互いに平行にでき
る。従って、これら両側壁部の内側面とローラの軸方向
両端面との間に、これら両面同士の摩擦を低減させる為
の油膜が十分に形成できて、ローラの回転に要する抵抗
を低減すると共に、ローラ及び板金製ロッカーアームの
摩耗量の低減を図れる。According to the cam follower provided with the sheet metal rocker arm of the present invention having the above-described structure and the method of assembling the same, the sheet metal rocker arm, the roller and the pivot are combined, and both ends of the pivot are made of the sheet metal. In a state of being fixedly connected to the pair of side walls constituting the rocker arm, the both side walls and the both axial end surfaces of the roller can be made parallel to each other. Therefore, an oil film for reducing friction between these two surfaces can be sufficiently formed between the inner side surfaces of these side wall portions and both end surfaces in the axial direction of the roller, thereby reducing the resistance required for the rotation of the roller, The wear amount of the roller and the sheet metal rocker arm can be reduced.
【００１５】[0015]
【発明の実施の形態】図１は、本発明の実施の形態の第
１例を示している。板金製ロッカーアーム１３は、低炭
素鋼板、肌焼鋼板等の金属板を打ち抜き成形し、更に曲
げ加工を施す事により造られ、互いにほぼ平行な１対の
側壁部３、３と、これら両側壁部３、３同士を連結する
連結部４（図５〜６参照）とを備える。尚、この様な板
金製ロッカーアーム１３は、例えば前述の図３〜６に示
した様にして造るが、この板金製ロッカーアーム１３自
体の製造方法は特に限定しない。又、この板金製ロッカ
ーアーム１３は、必ずしも１枚の金属板により形成する
必要はない。例えば、上記１対の側壁部３、３と連結部
４とを別々に形成した後、これら別々に造った部品同士
を溶接により結合しても良い。この場合には、弁体との
係合により大きな応力を発生する上記連結部４の板厚
を、あまり大きな応力を発生しない、上記各側壁部３、
３の板厚よりも大きくできる。更には、上記板金製ロッ
カーアーム１３を１枚の金属板により造る場合でも、上
記連結部４に相当する部分の板厚を、増厚加工により大
きくする事もできる。本発明の要旨は、上記１対の側壁
部３、３部分にあるので、板金製ロッカーアーム１３自
体の製造方法が何れの場合でも、本発明の対象となる。
又、側壁部３、３以外の部分の形状及び構造は、図示の
場合と異なっても良い。更には、側壁部３、３のうちの
ローラを支持する部分の位置も、前述の図４〜６に示す
様な長さ方向中間部に限らず、長さ方向端部でも良い。FIG. 1 shows a first embodiment of the present invention. The rocker arm 13 made of sheet metal is formed by punching and forming a metal plate such as a low carbon steel plate, a case hardening steel plate and the like, and then performing a bending process. And a connecting portion 4 (see FIGS. 5 and 6) for connecting the portions 3 and 3 to each other. The sheet metal rocker arm 13 is manufactured, for example, as shown in FIGS. 3 to 6 described above, but the method of manufacturing the sheet metal rocker arm 13 itself is not particularly limited. Further, the sheet metal rocker arm 13 does not necessarily need to be formed of one metal plate. For example, after the pair of side walls 3 and 3 and the connecting portion 4 are separately formed, these separately manufactured components may be joined by welding. In this case, the thickness of the connecting portion 4 which generates a large stress due to engagement with the valve body is reduced by the side wall portions 3 which do not generate a large stress.
3 can be larger than the plate thickness. Further, even when the sheet metal rocker arm 13 is made of one metal plate, the thickness of the portion corresponding to the connecting portion 4 can be increased by thickening. Since the gist of the present invention lies in the pair of side wall portions 3 and 3, the present invention is applicable to any method of manufacturing the sheet metal rocker arm 13 itself.
Further, the shape and structure of portions other than the side wall portions 3 and 3 may be different from those shown in the drawings. Further, the position of the portion of the side wall portions 3 and 3 supporting the roller is not limited to the intermediate portion in the longitudinal direction as shown in FIGS.
【００１６】何れにしても、上記板金製ロッカーアーム
１３を構成する１対の側壁部３、３の互いに整合する位
置には、１対の通孔１４、１４を形成している。そし
て、これら両通孔１４、１４同士の間に枢軸１５を掛け
渡している。この枢軸１５は、軸受鋼等の炭素鋼により
（好ましくは中空円管状に）形成し、外周面中間部は焼
き入れにより硬化しており、両端部は焼き入れせずに柔
らかい（生の）ままの状態としている。又、上記各通孔
１４、１４の外端（互いに反対側の端）開口周縁部に
は、それぞれ円すい凹面状の面取り部１６、１６を、全
周に亙って形成している。更に、上記枢軸１５の中間部
で上記１対の側壁部３、３同士の間部分の周囲には、軸
受鋼或はセラミックにより円筒状に形成したローラ１７
を、ラジアルニードル軸受１８により、回転自在に支持
している。In any case, a pair of through-holes 14, 14 are formed at positions where the pair of side walls 3, 3 constituting the sheet metal rocker arm 13 are aligned with each other. The pivot 15 is extended between the two through holes 14. The pivot 15 is formed of carbon steel such as bearing steel (preferably in the form of a hollow circular tube), the middle of the outer peripheral surface is hardened by quenching, and both ends are soft (raw) without quenching. State. In addition, conical concave chamfers 16 are formed on the outer periphery of the outer ends (opposite ends) of the through holes 14 over the entire circumference. Further, a roller 17 formed of bearing steel or ceramic into a cylindrical shape is provided around the portion between the pair of side wall portions 3, 3 at an intermediate portion of the pivot shaft 15.
Are rotatably supported by a radial needle bearing 18.
【００１７】上記枢軸１５は、その両端部を上記両通孔
１４、１４の内周面に向けかしめ広げる事により、上記
１対の側壁部３、３同士の間に掛け渡す状態で固定して
いる。即ち、上記枢軸１５の両端部を上記両通孔１４、
１４内に位置させた状態で、この枢軸１５の両端面に、
円環状でくさび状の尖端縁を有する、図示しないかしめ
治具の先端を強く押し付ける。そして、上記枢軸１５の
両端部外径寄り部分を直径方向外方に塑性変形させて、
この枢軸１５の両端部外周面を上記面取り部１６、１６
に向けかしめ付ける。この状態で、この枢軸１５が上記
両通孔１４、１４から抜け出したり、或はこれら両通孔
１４、１４の内側で回転する事がなくなる。The pivot 15 is fixed in a state of being bridged between the pair of side walls 3, 3 by crimping the both ends toward the inner peripheral surfaces of the through holes 14, 14. I have. That is, both ends of the pivot 15 are connected to the two through holes 14,
14, with both ends of this pivot 15
The tip of an unillustrated caulking jig having an annular wedge-shaped pointed edge is strongly pressed. Then, both ends of the pivot 15 near the outer diameter are plastically deformed radially outward,
The outer peripheral surfaces of both ends of the pivot 15 are chamfered to the chamfered portions 16, 16.
To crimp. In this state, the pivot 15 does not come out of the through holes 14 or rotate inside the through holes 14.
【００１８】特に、本発明の場合には、図１（Ａ）に示
した、上記枢軸１５の両端部をかしめ広げる以前の状態
で、上記１対の側壁部３、３のうちの上記各通孔１４、
１４を形成した部分の間隔Ｄ0 を、図１（Ｂ）に示し
た、上記枢軸１５の両端部をかしめ広げた状態でのこの
部分の間隔Ｄ1 よりも広く（Ｄ0 ＞Ｄ1 ）している。即
ち、本例の場合には、図１（Ａ）に誇張して示す様に、
上記各側壁部３、３を、それぞれの内側面（互いに対向
する側面）が凹面となる方向に、断面円弧状に湾曲させ
ている。そして、図１（Ｂ）に示す様に、上記枢軸１５
の両端部をかしめ広げた状態で、上記１対の側壁部３、
３同士が平行になる様にしている。In particular, in the case of the present invention, before each end of the pivot 15 is swaged as shown in FIG. Hole 14,
The distance D 0 of the formed portions 14, shown in FIG. 1 (B), larger than the distance D 1 of the this portion in a state in which spread caulking both end portions of the pivot 15 (D 0> D 1) and ing. That is, in the case of this example, as shown exaggeratedly in FIG.
Each of the side walls 3, 3 is curved in an arc-shaped cross section in a direction in which the respective inner side surfaces (side surfaces facing each other) become concave. Then, as shown in FIG.
In a state where both end portions of the pair are swaged, the pair of side wall portions 3,
3 are parallel to each other.
【００１９】即ち、図１（Ｂ）に示す様な、板金製ロッ
カーアームを備えたカムフォロアを組み立てる場合に
は、上記両側壁部３、３同士の間に前記ローラ１７及び
ラジアルニードル軸受１８を配置した状態で、これらロ
ーラ１７、ラジアルニードル軸受１８及び上記１対の通
孔１４、１４に上記枢軸１５を挿通した後、この枢軸１
５の両端部をこれら両通孔１４、１４の内周面に向けか
しめ広げる。この際、かしめ広げた部分が前記各面取り
部１６、１６に強く当接し、上記１対の側壁部３、３の
うちの上記各通孔１４、１４を形成した部分を、互いに
近づく方向に強く押圧する。この結果、上記各側壁部
３、３が弾性変形して、図１（Ｂ）に示す様に、これら
各側壁部３、３の内側面と上記ローラ１７の軸方向両端
面とが平行になる。That is, when assembling a cam follower having a rocker arm made of sheet metal as shown in FIG. 1B, the roller 17 and the radial needle bearing 18 are arranged between the side walls 3, 3. In this state, the pivot shaft 15 is inserted through the roller 17, the radial needle bearing 18, and the pair of through holes 14, 14, and then the pivot shaft 1 is rotated.
5 are crimped toward the inner peripheral surfaces of both through holes 14. At this time, the swaged portion strongly contacts the chamfered portions 16, 16, and the portions of the pair of side walls 3, in which the through holes 14, 14 are formed, are strongly pressed in a direction approaching each other. Press. As a result, the side walls 3 and 3 are elastically deformed, and the inner side surfaces of the side walls 3 and 3 are parallel to both axial end surfaces of the roller 17 as shown in FIG. .
【００２０】この様に、組立完了の状態で、上記各側壁
部３、３の内側面と上記ローラ１７の軸方向両端面とが
平行になる為、このローラ１７が軸方向に変位し、何れ
かの側壁部３の内側面とローラ１７の軸方向端面とが摺
接した場合でも、摺接面積を十分に確保できる。この
為、摺接部に、これら両面同士の摩擦を低減させる為の
油膜を十分に形成できて、上記ローラ１７の回転に要す
る抵抗を低減すると共に、このローラ１７及び前記板金
製ロッカーアーム１３の摩耗量の低減を図れる。As described above, when the assembly is completed, the inner side surfaces of the side walls 3 and 3 and the both end surfaces in the axial direction of the roller 17 are parallel to each other, so that the roller 17 is displaced in the axial direction. Even when the inner side surface of the side wall portion 3 slides against the axial end surface of the roller 17, a sufficient sliding contact area can be ensured. For this reason, an oil film for reducing the friction between these two surfaces can be sufficiently formed on the sliding contact portion, so that the resistance required for the rotation of the roller 17 is reduced, and the roller 17 and the rocker arm 13 made of sheet metal are formed. The amount of wear can be reduced.
【００２１】次に、図２は、本発明の実施の形態の第２
例を示している。本例の場合には、１対の側壁部３、３
のうち、枢軸１５（図１参照）の両端部を係止する為の
通孔１４、１４を形成した部分の幅方向一端縁（図２の
下端縁）同士を、連結部４により互いに連結している。
そして、上記各通孔１４、１４は、上記各側壁部３、３
の他端縁寄り部分の互いに整合する位置に形成してい
る。この様な形状の板金製ロッカーアーム１３ａに本発
明を実施する場合には、上記枢軸１５の両端部をかしめ
広げる以前の状態で、上記両側壁部３、３同士の間隔
を、図２に実線で誇張して示す様に、上記各通孔１４、
１４を形成した他端縁寄り部分で広く、一端縁寄り部分
で狭くする。上記枢軸１５の両端部を上記両側壁部３、
３に結合固定すべく、この枢軸１５の両端部をかしめ広
げた場合には、図２に鎖線で示す様に、上記両側壁部
３、３の他端縁寄り部分の間隔が狭まって、これら両側
壁部３、３の内側面同士が互いに平行になる。その他の
構成及び作用に就いては、上述した第１例の場合と同様
である。FIG. 2 shows a second embodiment of the present invention.
An example is shown. In the case of this example, a pair of side wall portions 3, 3
Of these, one end in the width direction (lower end in FIG. 2) of a portion in which through holes 14, 14 for locking both ends of the pivot 15 (see FIG. 1) are connected to each other by the connecting portion 4. ing.
And each said through-hole 14, 14 is each said side wall part 3,3.
Are formed at positions that are aligned with each other at the other end edge portion. When the present invention is applied to the rocker arm 13a made of sheet metal having such a shape, before the both ends of the pivot 15 are swaged apart, the distance between the side walls 3, 3 is shown by a solid line in FIG. As shown exaggeratedly in each of the through holes 14,
It is widened at the portion near the other end where 14 is formed and narrowed at the portion near the one end. The both ends of the pivot 15 are connected to the both side walls 3,
When the both ends of the pivot 15 are swaged and widened in order to fix them to the joint 3, as shown by a chain line in FIG. The inner side surfaces of the side walls 3 are parallel to each other. Other configurations and operations are the same as those of the first example described above.
【００２２】尚、本発明を実施する場合に、枢軸１５
（図１〜２）とバルブ係合部１２（図６）との平行度
（一方を他方に向け平行移動させて重ね合わせたと仮定
した場合に於ける凹凸の差）は、０．０１０mm以下にす
る事が、偏荷重を防止して耐久性を維持する面からは好
ましい。同様の理由で、上記枢軸１５の両端部を支持す
る為、各側壁部３、３に形成した通孔１４、１４のこれ
ら各側壁部３、３に対する直角度（これら各通孔１４、
１４の中心軸に対し直角な仮想平面に対する各側壁部
３、３の凹凸の差）を０．０２５mm以下にする事が好ま
しい。又、上記バルブ係合部１２の表面粗さは０．４ａ
（μｍRa）以下に、ピボット部６（図６）の表面粗さは
３．２Ｓ（Ｒmax ）以下に、それぞれ抑える事が、これ
ら各部１２、６と当接する弁体の基端部若しくはラッシ
ュアジャスタの先端部の摩耗防止を図る上からは好まし
い。更に、上記バルブ係合部１２の幅方向両側に設けた
壁部の直角度を０．０５０mm以下、上記１対の通孔１
４、１４の同軸度を０．００６mm以下、これら各通孔１
４、１４の真円度を０．００５mm以下、これら各通孔１
４、１４の内周面の表面粗さを０．４ａ以下にする事
が、板金製ロッカーアームを備えたカムフォロアの性能
を確保する面からは好ましい。尚、これらの条件を満た
すべく、板金製ロッカーアーム１３、１３ａに、プレス
加工によるサイジングの他、切削加工、研磨加工等、必
要とする機械加工を施す。When the present invention is carried out, the pivot 15
The degree of parallelism (the difference in unevenness when assuming that one is parallel-moved toward the other and superposed) is less than 0.010 mm (FIGS. 1-2) and the valve engaging portion 12 (FIG. 6). Is preferable from the viewpoint of preventing uneven load and maintaining durability. For the same reason, in order to support both ends of the pivot 15, the perpendicularity of the through holes 14, 14 formed in the side walls 3, 3 to the respective side walls 3, 3 (the through holes 14, 3).
It is preferable to set the difference between the irregularities of the side walls 3 and 3 with respect to the virtual plane perpendicular to the center axis of 14 to 0.025 mm or less. The surface roughness of the valve engaging portion 12 is 0.4a.
(ΜmRa) or less, and the surface roughness of the pivot portion 6 (FIG. 6) should be suppressed to 3.2S (R max ) or less, respectively. It is preferable from the viewpoint of preventing wear of the tip portion of the device. Further, the squareness of the wall portions provided on both sides in the width direction of the valve engaging portion 12 is 0.050 mm or less, and the pair of through holes 1
The coaxiality of each of the holes 4 and 14 is 0.006 mm or less.
The roundness of each of the holes 4 and 14 is 0.005 mm or less.
It is preferable that the surface roughness of the inner peripheral surface of each of 4 and 14 be 0.4a or less from the viewpoint of ensuring the performance of the cam follower having the rocker arm made of sheet metal. In order to satisfy these conditions, the rocker arms 13 and 13a made of sheet metal are subjected to necessary machining such as cutting and polishing in addition to sizing by press working.
【００２３】[0023]
【発明の効果】本発明の板金製ロッカーアームを備えた
カムフォロアとその組立方法は、以上に述べた通り構成
され作用するので、ローラの回転を軽い力で行なえ、し
かも各部の摩耗を低減して優れた耐久性を有する板金製
ロッカーアームを備えたカムフォロアを実現できる。The cam follower having the rocker arm made of sheet metal and the method of assembling the same according to the present invention are constructed and operated as described above, so that the rotation of the roller can be performed with a small force and the wear of each part can be reduced. A cam follower having a sheet metal rocker arm having excellent durability can be realized.
【図面の簡単な説明】[Brief description of the drawings]
【図１】本発明の実施の形態の第１例を示しており、
（Ａ）は枢軸の両端部をかしめ広げる以前の状態を、
（Ｂ）は同じくかしめ広げた後の状態を、それぞれ示
す、図６（Ｂ）のＸ−Ｘ断面に相当する図。FIG. 1 shows a first example of an embodiment of the present invention;
(A) shows the state before crimping both ends of the axis,
FIG. 7B is a view corresponding to a cross section taken along line XX of FIG.
【図２】同第２例を示す、板金製ロッカーアームの部分
略断面図。FIG. 2 is a partial schematic cross-sectional view of a rocker arm made of sheet metal, showing the second example.
【図３】従来から知られている板金製ロッカーアームの
製造時に第一工程で造られた素板を示しており、（Ａ）
は平面図、（Ｂ）は（Ａ）のａ−ａ断面図。FIG. 3 shows a raw plate manufactured in a first step at the time of manufacturing a conventionally known rocker arm made of sheet metal, and (A)
2 is a plan view, and FIG. 2B is a cross-sectional view taken along line aa of FIG.
【図４】同じく第二工程を経て造られた第一中間素材を
示しており、（Ａ）は平面図、（Ｂ）は（Ａ）のａ−ａ
断面図。4A and 4B show a first intermediate material similarly produced through the second step, wherein FIG. 4A is a plan view and FIG. 4B is aa of FIG.
Sectional view.
【図５】同じく第三工程を経て造られた第二中間素材を
示しており、（Ａ）は平面図、（Ｂ）は（Ａ）のａ−ａ
断面図。5A and 5B show a second intermediate material similarly manufactured through the third step, wherein FIG. 5A is a plan view and FIG. 5B is aa of FIG.
Sectional view.
【図６】同じく第四工程を経て造られた第三中間素材を
示しており、（Ａ）は平面図、（Ｂ）は（Ａ）のａ−ａ
断面図。FIG. 6 shows a third intermediate material similarly produced through the fourth step, wherein (A) is a plan view and (B) is aa of (A).
Sectional view.
１ 素板 ２ 第一中間素材 ３ 側壁部 ４ 連結部 ５ ローラ収容凹部 ６ ピボット部 ７ 透孔 ８ 第二中間素材 ９ 突出部 １０ 第三中間素材 １１ 開口 １２ バルブ係合部 １３、１３ａ 板金製ロッカーアーム １４ 通孔 １５ 枢軸 １６ 面取り部 １７ ローラ １８ ラジアルニードル軸受 REFERENCE SIGNS LIST 1 base plate 2 first intermediate material 3 side wall portion 4 connecting portion 5 roller accommodating concave portion 6 pivot portion 7 through hole 8 second intermediate material 9 projecting portion 10 third intermediate material 11 opening 12 valve engaging portion 13, 13a sheet metal rocker Arm 14 Through-hole 15 Axis 16 Chamfer 17 Roller 18 Radial needle bearing
───────────────────────────────────────────────────── フロントページの続き Ｆターム(参考） 3G013 BA06 BC11 BD35 3G016 BB09 BB22 CA01 CA05 CA22 CA29 CA32 CA44 EA03 EA14 FA07 FA13 FA35 FA39 GA00 GA02 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3G013 BA06 BC11 BD35 3G016 BB09 BB22 CA01 CA05 CA22 CA29 CA32 CA44 EA03 EA14 FA07 FA13 FA35 FA39 GA00 GA02
Claims (2)
１対の側壁部と、これら両側壁部同士を連結する連結部
とを備えた板金製ロッカーアームと、これら両側壁部の
互いに整合する位置に形成した１対の通孔同士の間に掛
け渡した状態で、その両端部をこれら両通孔の内周面に
向けかしめ広げる事により、上記１対の側壁部同士の間
に掛け渡す状態で固定した枢軸と、この枢軸の中間部周
囲に回転自在に支持したローラとから成る板金製ロッカ
ーアームを備えたカムフォロアに於いて、上記枢軸の両
端部をかしめ広げる以前の状態で、上記１対の側壁部の
うちの上記各通孔を形成した部分の間隔を、上記枢軸の
両端部をかしめ広げた状態でのこの部分の間隔よりも広
くしておく事により、この枢軸の両端部をかしめ広げた
状態で上記１対の側壁部同士を平行にした事を特徴とす
る板金製ロッカーアームを備えたカムフォロア。1. A rocker arm made of a metal plate and provided with a pair of side walls substantially parallel to each other and a connecting portion connecting the both side walls, and the two side walls are aligned with each other. In a state of being bridged between the pair of through holes formed at the positions, the both ends are crimped toward the inner peripheral surfaces of these through holes to bridge between the pair of side wall portions. In a cam follower provided with a sheet metal rocker arm composed of a pivot fixed in a state and a roller rotatably supported around an intermediate part of the pivot, the cam follower may be used in a state before both ends of the pivot are swaged. By making the distance between the portions where the above-mentioned through holes are formed in the pair of side walls wider than the distance between the portions where the both ends of the pivot are crimped, the both ends of the pivot can be extended. The pair of sides above with the crimped state A cam follower with a sheet metal rocker arm, characterized in that the walls are parallel to each other.
側壁部同士を連結する連結部とを備え、これら両側壁部
の互いに整合する位置に１対の通孔を形成した板金製ロ
ッカーアームを造ると共に、上記両側壁部同士の間にロ
ーラを配置した状態で、このローラ及び上記１対の通孔
に枢軸を挿通した後、この枢軸の両端部をこれら両通孔
の内周面に向けかしめ広げる事により、この枢軸を上記
１対の側壁部同士の間に掛け渡す状態で固定する板金製
ロッカーアームを備えたカムフォロアの組立方法に於い
て、上記枢軸の両端部をかしめ広げる以前の状態で、上
記１対の側壁部のうちの上記各通孔を形成した部分の間
隔を、上記枢軸の両端部をかしめ広げた状態でのこの部
分の間隔よりも広くしておき、この枢軸の両端部をかし
め広げる事に伴って上記１対の側壁部のうちの上記各通
孔を形成した部分の間隔を狭くする事により、上記１対
の側壁部同士を平行にする事を特徴とする板金製ロッカ
ーアームを備えたカムフォロアの組立方法。2. A rocker made of sheet metal, comprising a pair of side walls and a connecting portion connecting the both side walls with a metal plate, and forming a pair of through holes at positions where the side walls are aligned with each other. After the arm is formed and a roller is disposed between the side walls, a pivot is inserted into the roller and the pair of through holes, and both ends of the pivot are connected to the inner peripheral surfaces of the two holes. In a method of assembling a cam follower provided with a sheet metal rocker arm for fixing the pivot in a state of being bridged between the pair of side walls, the two ends of the pivot are crimped. In this state, the interval between the portions where the respective through holes are formed in the pair of side wall portions is made larger than the interval between the portions where both ends of the pivot are crimped and widened. With crimping both ends of A cam follower having a rocker arm made of sheet metal, characterized in that the pair of side walls is made parallel by narrowing the interval between the portions where the through holes are formed in the pair of side walls. Assembly method.
Priority Applications (10)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10225661A JP2000054811A (en) | 1998-08-10 | 1998-08-10 | Cam follower having sheet metal rocker arm and its assembling method |
| US09/265,957 US6199527B1 (en) | 1998-03-12 | 1999-03-11 | Sheet metal rocker arm, manufacturing method thereof, cam follower with said rocker arm, and assembling method thereof |
| US09/729,111 US6334416B2 (en) | 1998-03-12 | 2000-12-05 | Sheet metal rocker arm, manufacturing method thereof, cam follower with said rocker arm, and assembling method thereof |
| US09/912,366 US6508215B2 (en) | 1998-03-12 | 2001-07-26 | Sheet metal rocker arm, manufacturing method thereof, cam follower with said rocker arm, and assembling method thereof |
| US09/912,387 US20010045198A1 (en) | 1998-03-12 | 2001-07-26 | Sheet metal rocker arm, manufacturing method thereof, cam follower with said rocker arm, and assembling method thereof |
| US10/101,868 US6601555B2 (en) | 1998-03-12 | 2002-03-21 | Sheet metal rocker arm, manufacturing method thereof, cam follower with said rocker arm, and assembling method thereof |
| US10/254,533 US6588101B2 (en) | 1998-03-12 | 2002-09-26 | Sheet metal rocker arm, manufacturing method thereof, cam follower with said rocker arm, and assembling method thereof |
| US10/288,452 US20030066502A1 (en) | 1998-03-12 | 2002-11-06 | Sheet metal rocker arm, manufacturing method thereof, cam follower with said rocker arm, and assembling method thereof |
| US10/342,235 US6672266B2 (en) | 1998-03-12 | 2003-01-15 | Sheet metal rocker arm, manufacturing method thereof, cam follower with said rocker arm, and assembling method thereof |
| US10/702,047 US6959676B2 (en) | 1998-03-12 | 2003-11-06 | Sheet metal rocker arm, manufacturing method thereof, cam follower with said rocker arm, and assembling method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10225661A JP2000054811A (en) | 1998-08-10 | 1998-08-10 | Cam follower having sheet metal rocker arm and its assembling method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2000054811A true JP2000054811A (en) | 2000-02-22 |
| JP2000054811A5 JP2000054811A5 (en) | 2005-06-30 |
Family
ID=16832803
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10225661A Pending JP2000054811A (en) | 1998-03-12 | 1998-08-10 | Cam follower having sheet metal rocker arm and its assembling method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2000054811A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2006013696A1 (en) * | 2004-08-02 | 2006-02-09 | Ntn Corporation | Rolling bearing for rocker arm |
| WO2020213630A1 (en) * | 2019-04-19 | 2020-10-22 | 株式会社日進製作所 | Rocker arm |
-
1998
- 1998-08-10 JP JP10225661A patent/JP2000054811A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2006013696A1 (en) * | 2004-08-02 | 2006-02-09 | Ntn Corporation | Rolling bearing for rocker arm |
| US7614374B2 (en) | 2004-08-02 | 2009-11-10 | Ntn Corporation | Rolling bearing for rocker arm |
| WO2020213630A1 (en) * | 2019-04-19 | 2020-10-22 | 株式会社日進製作所 | Rocker arm |
| JPWO2020213630A1 (en) * | 2019-04-19 | 2021-12-16 | 株式会社日進製作所 | Rocker arm |
| JP7162733B2 (en) | 2019-04-19 | 2022-10-28 | 株式会社日進製作所 | rocker arm |
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