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の製造方法の改良に関する。
This invention is built into a valve mechanism of an engine, and is made by pressing a metal plate among rocker arms for converting the rotation of a camshaft into a reciprocating motion of a valve body (intake valve and exhaust valve). The present invention relates to an improvement in a method for manufacturing a sheet metal rocker arm.
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それぞれの軸方向に往復運動させる。
The reciprocating engine (reciprocating piston engine) is provided with an intake valve and an exhaust valve that open and close in synchronization with the rotation of the crankshaft except for some two-cycle engines. In such a reciprocating engine, the movement of the camshaft that rotates in synchronization with the rotation of the crankshaft (in the case of a four-cycle engine, at half the rotational speed) The intake valve and the exhaust valve are reciprocated in the respective axial directions.
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低コストで得る為に、鋼板等の金属板に、打ち抜き加工、曲げ加工等のプレス加工を施す事により造る事が考えられ、一部で実施されている。この様な板金製ロッカーアームに就いて記載した刊行物として、特許文献１〜２が存在する。図５は、このうちの特許文献１に記載された板金製ロッカーアーム１を示している。この板金製ロッカーアーム１は、互いにほぼ平行な１対の側壁部２、２と、これら両側壁部２、２の幅方向一端縁同士を連結する連結部３及び第二連結部４とを有する。又、これら両側壁部２、２の長さ方向中間部に１対の通孔５を、互いに同心に形成し、これら両通孔５に、カムと係合するローラ６を回転自在に支持する為の支持軸７の両端部を支持自在としている。上記連結部３及び第二連結部４のうち、連結部３の片面には、弁体の基端部を突き当てる為の係合部８を、第二連結部４に、ラッシュアジャスタの先端部を突き当てる為の第二係合部９を、それぞれ形成している。この第二係合部９は、上記第二連結部４の中央部を厚さ方向に塑性変形させる事により、球状凹面としている。
In order to obtain a rocker arm to be incorporated into such a valve mechanism of an engine at a low cost, it is possible to make it by subjecting a metal plate such as a steel plate to stamping, bending, etc. Has been. Patent Documents 1 and 2 exist as publications describing such rocker arm made of sheet metal. FIG. 5 shows a sheet metal rocker arm 1 described in Patent Document 1 among them. The sheet metal rocker arm 1 has a pair of side wall portions 2 and 2 that are substantially parallel to each other, and a connecting portion 3 and a second connecting portion 4 that connect one end edges in the width direction of both side wall portions 2 and 2. . In addition, a pair of through holes 5 are formed concentrically with each other in the longitudinal direction intermediate portion of the both side wall portions 2 and 2, and the rollers 6 engaged with the cams are rotatably supported in these through holes 5. Thus, both end portions of the support shaft 7 are freely supported. Of the connecting portion 3 and the second connecting portion 4, an engaging portion 8 for abutting the base end portion of the valve body is provided on one surface of the connecting portion 3, and the distal end portion of the lash adjuster is provided on the second connecting portion 4. The second engaging portions 9 for abutting each other are formed. The second engaging portion 9 has a spherical concave surface by plastically deforming the central portion of the second connecting portion 4 in the thickness direction.
上述の様な板金製ロッカーアーム１の製造方法に就いては、前記特許文献１に記載されている。要するに、板金製ロッカーアーム１を造る場合には、第一工程として、図６に示す様に、１枚の金属板１０に絞り加工を施す事により、この金属板１０の一部に矩形状の壁部形成用凹部１１を形成する。次いで、第二工程として、この金属板１０に打ち抜き加工を施す事により、図７に示す様に、中央部に透孔１２を形成した、所定の外形を有する素板１３を形成する。この透孔１２は、上記壁部形成用凹部１１に対応する位置に設けており、この透孔１２の内周縁の幅方向両側から１対の凸円弧状部１４、１４が突出している。続いて、第三工程として、図８に示す様に、上記素板１３にプレス加工に基づく曲げ加工を施す事により、中間素材１５を造る。この中間素材１５は、互いにほぼ平行な１対の側壁部２、２と、これら両側壁部２、２の幅方向一端縁同士を連結する連結部３及び第二連結部４とを形成して成る。上記各側壁部２、２は、上記各凸円弧状部１４、１４をバーリング処理によりほぼ平行に対向させると共に、上記素材１３（図７）の幅方向｛図７（ａ）の上下方向｝両側部分をほぼ直角に、同方向に曲げ加工して成る。この様な第三工程の後、第四工程として、図９に示す様に、上記連結部３及び第二連結部４に、係合部８及び第二係合部９を、それぞれ形成して、第二中間素材４７とする。上記第二係合部９は、上記第二の連結部４に、反球状に絞り加工を施す事により形成する。そして、上記第二中間素材４７の各側壁部２、２の互いに整合する位置に１対の通孔５（図５参照）を形成する打ち抜き工程を経て、前述の図５に示した板金製ロッカーアーム１の完成品とする。
The manufacturing method of the sheet metal rocker arm 1 as described above is described in Patent Document 1. In short, when the sheet metal rocker arm 1 is manufactured, as shown in FIG. 6, as a first step, a single metal plate 10 is drawn to form a rectangular shape on a part of the metal plate 10. A wall forming recess 11 is formed. Next, as a second step, by punching the metal plate 10, as shown in FIG. 7, a base plate 13 having a predetermined outer shape with a through hole 12 formed at the center is formed. The through-hole 12 is provided at a position corresponding to the wall-forming recess 11, and a pair of convex arcuate portions 14, 14 project from both sides in the width direction of the inner periphery of the through-hole 12. Subsequently, as a third step, as shown in FIG. 8, the intermediate material 15 is made by bending the base plate 13 based on press working. The intermediate material 15 forms a pair of side wall portions 2 and 2 that are substantially parallel to each other, and a connecting portion 3 and a second connecting portion 4 that connect one end edges in the width direction of both side wall portions 2 and 2. Become. The side wall portions 2 and 2 have the convex arcuate portions 14 and 14 facing each other substantially in parallel by a burring process, and both sides of the material 13 (FIG. 7) in the width direction {vertical direction in FIG. 7 (a)}. The part is bent at a right angle in the same direction. After such a third step, as a fourth step, as shown in FIG. 9, an engaging portion 8 and a second engaging portion 9 are formed on the connecting portion 3 and the second connecting portion 4, respectively. The second intermediate material 47 is used. The second engaging portion 9 is formed by subjecting the second connecting portion 4 to an antispherical drawing process. Then, after a punching process of forming a pair of through holes 5 (see FIG. 5) at positions where the side walls 2, 2 of the second intermediate material 47 are aligned with each other, the sheet metal locker shown in FIG. Assume that arm 1 is finished.
この様な図５〜９に示した板金製ロッカーアームの製造方法の従来例の第１例の場合、中央部に透孔１２を形成した素板１３（図７）を造った後、この素板１３に曲げ加工を施す事により、１対の側壁部２、２と連結部３及び第二連結部４とを有する板金製ロッカーアーム１を造っている。これに対して、板金製ロッカーアームの別の製造方法として、透孔がない所定の形状（外形）を有する素板を形成した後、この素板にプレス加工に基づく曲げ加工（絞り加工）を施す事により、１対の側壁部と連結部とを有する第一中間素材を造り、その後、この第一中間素材の連結部に打ち抜き加工を施す事により、この連結部に透孔を形成した第二中間素材を造る製造方法も、従来から考えられている。図１０〜１３は、この様に従来から考えられている、板金製ロッカーアームの製造方法の従来例の第２例を示している。この従来例の第２例により製造する板金製ロッカーアーム１ａは、図１０に示す様に、１対の側壁部２、２と、これら両側壁部２、２の幅方向一端縁｛図１０（ｃ）の左端縁、図１０（ｄ）の右端縁）同士を連結する連結部３及び第二連結部４とを有する。又、これら連結部３及び第二連結部４に、係合部８及び第二係合部９を、それぞれ形成している。又、上記両側壁部２、２の曲げ方向（先端の向き）を、上記係合部３及び第二係合部４を形成する面（下面）とは逆の側の、上方としている。そして、上記各側壁部２、２の長さ方向中間部に１対の通孔５、５を、互いに同心に形成している。
In the case of the first example of the conventional method of manufacturing the sheet metal rocker arm shown in FIGS. 5 to 9, after the base plate 13 (FIG. 7) having the through-hole 12 formed in the central portion is manufactured, By bending the plate 13, the sheet metal rocker arm 1 having a pair of side wall portions 2, 2, a connecting portion 3, and a second connecting portion 4 is made. On the other hand, as another manufacturing method of the sheet metal rocker arm, after forming a base plate having a predetermined shape (outer shape) without a through hole, the base plate is subjected to bending processing (drawing processing) based on press processing. By forming a first intermediate material having a pair of side wall portions and a connecting portion, and then punching the connecting portion of the first intermediate material, a through hole is formed in the connecting portion. Conventionally, a manufacturing method for producing a two-intermediate material has been considered. 10 to 13 show a second example of a conventional example of a method for manufacturing a sheet metal rocker arm, which has been conventionally considered. As shown in FIG. 10, a sheet metal rocker arm 1a manufactured according to the second example of the conventional example has a pair of side wall portions 2, 2 and one end in the width direction of both side wall portions 2, 2 {FIG. c) a left end edge of FIG. 10 and a right end edge of FIG. Further, an engaging portion 8 and a second engaging portion 9 are formed on the connecting portion 3 and the second connecting portion 4, respectively. Further, the bending direction (direction of the tip) of the side wall portions 2 and 2 is set to the upper side opposite to the surface (lower surface) forming the engaging portion 3 and the second engaging portion 4. A pair of through holes 5 and 5 are formed concentrically with each other in the longitudinal direction intermediate portion of each of the side wall portions 2 and 2.
図１０に示した板金製ロッカーアーム１ａを製造する為に、板金製ロッカーアームの製造方法の従来例の第２例の場合には、第一工程として、肌焼き鋼板の如き炭素鋼板等、十分な剛性を有する金属板（平板材若しくはコイル材）を、図示しないプレス装置の打ち抜き型と受型との間に供給し、これら両型同士の間で、図１１に示す様な素板１８を打ち抜き形成する。この素板１８は、略矩形状の基部１９の幅方向両端部に１対の翼状部２０、２０を設けて成る。
In order to manufacture the sheet metal rocker arm 1a shown in FIG. 10, in the case of the second example of the conventional method of manufacturing the sheet metal rocker arm, as the first step, a carbon steel sheet such as a case-hardened steel sheet is sufficient. A metal plate (flat plate material or coil material) having a sufficient rigidity is supplied between a punching die and a receiving die of a press device (not shown), and a base plate 18 as shown in FIG. Stamped to form. The base plate 18 is formed by providing a pair of wing-like portions 20 and 20 at both ends in the width direction of a substantially rectangular base portion 19.
上記素板１８は、続く第二工程で、図１２に示す様な第一中間素材２１とする。この第二工程では、上記素板１８を、図示しないプレス装置に組み付けた押型と受型との間に供給して強く押圧し、上記素板１８の幅方向両端寄り部分に曲げ加工を施す。そして、上記素板１８を、１対の側壁部２、２と、これら両側壁部２、２の幅方向｛図１２（ｃ）（ｄ）の左右方向｝端縁同士を連結する連結部２２とから成る、上記第一中間素材２１とする。
The base plate 18 is a first intermediate material 21 as shown in FIG. In this second step, the base plate 18 is supplied between a pressing die and a receiving die assembled in a not-shown pressing device and pressed strongly, and bending processing is performed on portions of the base plate 18 near both ends in the width direction. Then, the base plate 18 is connected to the pair of side wall portions 2 and 2 and the side walls 2 and 2 in the width direction {right and left direction in FIGS. 12 (c) and 12 (d)}. The first intermediate material 21 is composed of
上述の様な第一中間素材２１には、続く第三工程で、図１３に示す様に矩形状の透孔２３を形成して、第二中間素材２４とする。この第二中間素材２４は、図示しないプレス加工装置に組み込んだ、プレス装置の打ち抜き型と受型との間に上記第一中間素材２１を供給し、これら両型同士の間で上記連結部２２（図１２）の中間部を打ち抜く事により、上記透孔２３を形成する。そして、上記連結部２２のうちの、透孔２３を挟んだ両側部分のうち、片側｛図１３（ａ）（ｂ）の右側｝部分が第一連結部３となり、他側｛図１３（ａ）（ｂ）の左側｝部分が第二連結部４となる。
In the first intermediate material 21 as described above, a rectangular through-hole 23 is formed as shown in FIG. The second intermediate material 24 supplies the first intermediate material 21 between a punching die and a receiving die of a press device, which is incorporated in a press working device (not shown), and the connecting portion 22 is provided between the two dies. The through-hole 23 is formed by punching out the middle part of FIG. Of the both side portions of the connecting portion 22 sandwiching the through hole 23, one side {the right side in FIGS. 13 (a) and 13 (b)} is the first connecting portion 3 and the other side {FIG. 13 (a). ) (Left side) of (b) is the second connecting portion 4.
上述の様にして構成した第二中間素材２４は、続く第四工程で、上記第一、第二連結部３、４を、押圧加工用の押型と受型との間にセットする。そして、この押型を受型に向け加圧して冷間鍛造を行ない、上記第一連結部３に、図示しない弁体の基端部を突き当てる為の第一の係合部８（図１０）を形成する。又、上記第二連結部４に、図示しないラッシュアジャスタの先端部を突き当てる為の第二の係合部９（図１０）を形成する。そして、その後の工程で、１対の側壁部２、２の中間部で互いに整合する位置に、それぞれ円形の通孔５、５を、プレス加工、或は旋削加工により形成して、前述の図１０に示した板金製ロッカーアーム１ａの完成品とする。これら両通孔５、５は、ローラ６を回転自在に支持する為の支持軸７（図５参照）の両端部を支持する為のものである。即ち、上記通孔５、５に両端部を支持した支持軸７の中間部周囲にローラ６を回転自在に支持すると共に、このローラ６の外周面をカムの外周面に当接させて、カムシャフトの回転運動を上記板金製ロッカーアーム１ａの揺動運動に変換自在とする。
The second intermediate material 24 configured as described above sets the first and second connecting portions 3 and 4 between the pressing mold and the receiving mold in the subsequent fourth step. Then, the pressing die is pressed toward the receiving die to perform cold forging, and a first engaging portion 8 (FIG. 10) for abutting a proximal end portion of a valve body (not shown) against the first connecting portion 3. Form. Further, a second engaging portion 9 (FIG. 10) for abutting the tip of a lash adjuster (not shown) is formed on the second connecting portion 4. Then, in the subsequent process, circular through holes 5 and 5 are respectively formed by press working or turning at positions where they are aligned with each other at the middle part of the pair of side wall parts 2 and 2. A finished product of the sheet metal rocker arm 1a shown in FIG. These through holes 5 and 5 are for supporting both ends of a support shaft 7 (see FIG. 5) for rotatably supporting the roller 6. That is, the roller 6 is rotatably supported around the intermediate portion of the support shaft 7 that supports both ends of the through holes 5 and 5, and the outer peripheral surface of the roller 6 is brought into contact with the outer peripheral surface of the cam. The rotational movement of the shaft can be freely converted into the rocking movement of the sheet metal rocker arm 1a.
上述した板金製ロッカーアームの製造方法の従来例の第１〜２例の場合、それぞれ次の様な改良すべき点がある。先ず、前述の図６〜９に示した従来例の第１例の場合、透孔１２を形成した素板１３に曲げ加工を施す事により、１対の側壁部２、２と第一、第二の連結部３、４とを有する中間素材１５を造っている。この場合、曲げ加工に伴い、中間素材１５の透孔１２の四隅周辺部に捩れ変形が発生し易くなり、著しい場合にはこの捩れ変形が更に進んで「重なり」と呼ばれる、２つの面同士が重なる様に変形する状態が生じる可能性がある。即ち、前述の図７に示した様な、透孔１２を有する素板１３に、幅方向（図７の上下方向）両側部分を図７の表側に曲げる様に曲げ加工を施すと、図１４に誇張して示す様に、第二連結部４の透孔１２の隅周辺に存在する透孔１２の内面同士の連続部が捻れる様に変形する（第一連結部３の透孔１２の隅周辺部の場合も同様。）。この結果、中間素材１５の透孔１２の四隅周辺部（図１４にイで囲んだ部分）に捩れ変形が発生し易くなる。
In the case of the first and second examples of the conventional method of manufacturing the metal plate rocker arm described above, there are the following points to be improved. First, in the case of the first example of the conventional example shown in FIGS. 6 to 9 described above, by bending the base plate 13 in which the through holes 12 are formed, the pair of side wall portions 2, 2 and the first, first, An intermediate material 15 having two connecting portions 3 and 4 is made. In this case, twisting deformation is likely to occur around the four corners of the through hole 12 of the intermediate material 15 along with the bending process, and in this case, the torsional deformation further proceeds and the two surfaces called “overlap” are formed. There is a possibility that a state of deformation occurs so as to overlap. That is, when the base plate 13 having the through holes 12 as shown in FIG. 7 is bent so that both side portions in the width direction (vertical direction in FIG. 7) are bent to the front side in FIG. As shown exaggeratedly, the continuous portion of the inner surfaces of the through holes 12 existing around the corners of the through holes 12 of the second connecting portion 4 is deformed so as to be twisted (the through holes 12 of the first connecting portion 3). The same applies to the corner area.) As a result, torsional deformation is likely to occur at the four corners of the through hole 12 of the intermediate material 15 (the portion surrounded by a in FIG. 14).
これに就いて、前述の図７に示した素板１３とは別形状の、図１５に示す、透孔１２を形成した素板１３ａに曲げ加工を施す事により、図１６に示す様な中間素材１５ａを造る場合を考えて、より詳しく説明する。図１５に示す様に、打ち抜き加工を施す事により透孔１２を形成した、曲げ加工を施す以前の素板１３ａでは、この透孔１３ａの内面の、長さ方向両端に位置するＡを付した面（Ａ面）と、幅方向両端に位置するＢを付した面（Ｂ面）とが、何れも素板１３ａの上面（図１５でＣを付した面）に対し直角方向に存在する。これに対して、図１６に示す様に１対の側壁部２、２を設けるべく曲げ加工を施した後の状態では、上記Ａ面が上記透孔１２の長さ方向（図１６の左右方向）に向いたままとなるの対し、上記Ｂ面は、側壁部２、２の高さ方向と同方向で、これら側壁部２、２同士を連結する連結部３の上面（図１６でＣを付した面）と同方向（図１６の上方）の、上記Ａ面とは直角な方向に向いた状態になる。この為、Ａ面とＢ面との連続部である透孔１２の四隅周辺部（図１６のロで囲んだ部分）に、「捩れ」と呼ばれる変形（捩れ変形）が発生する。この様な捩れ変形の発生は、中間素材１５、１５ａ（図８、１４、１６）の一部に亀裂等の損傷が生じ易くなり、板金製ロッカーアーム１の歩留りが悪化する原因となる。
Accordingly, by bending the base plate 13a having the through holes 12 shown in FIG. 15, which has a different shape from the base plate 13 shown in FIG. 7, the intermediate shown in FIG. The case where the material 15a is made will be described in more detail. As shown in FIG. 15, in the base plate 13a before the bending process is performed, the through holes 12 are formed by punching, and A is located at both ends in the length direction of the inner surface of the through holes 13a. Both the surface (A surface) and the surface (B surface) with B positioned at both ends in the width direction are present in a direction perpendicular to the upper surface (surface with C in FIG. 15) of the base plate 13a. On the other hand, as shown in FIG. 16, in the state after bending to provide a pair of side wall portions 2, 2, the A surface is the length direction of the through-hole 12 (the left-right direction in FIG. 16). The B surface is in the same direction as the height direction of the side wall portions 2 and 2 and the upper surface of the connecting portion 3 that connects the side wall portions 2 and 2 (C in FIG. 16). It is in a state in which it is oriented in a direction perpendicular to the surface A in the same direction (upper surface in FIG. 16) as the attached surface. For this reason, deformation (torsional deformation) called “twisting” occurs in the four corner peripheral portions (portions surrounded by B in FIG. 16) of the through-hole 12 that is a continuous portion of the A surface and the B surface. The occurrence of such torsional deformation is liable to cause damage such as cracks in a part of the intermediate materials 15 and 15a (FIGS. 8, 14, and 16), and causes the yield of the sheet metal rocker arm 1 to deteriorate.
又、上述の図１５に示した素板１３ａとは別形状の素板から造った板金製ロッカーアームとして、図１７〜１９に示す様な板金製ロッカーアーム４８、４９も、従来から考えられている。これら図１７〜１９に示した構造の場合には、透孔１２の四隅周辺部の捩れ変形が生じるだけでなく、この捩れ変形が更に進んで、「重なり」と呼ばれる変形状態が生じる可能性がある。即ち、これら各図の構造も、透孔１２を有する素板に曲げ加工を施す事により造ったものであるが、曲げ加工以前の透孔１２の内面のうち、長さ方向両端に位置するＡを付した面（Ａ面）とＢを付した面（Ｂ面）との連続部で、曲げ加工後に、透孔１２の四隅周辺部（図１７のハで囲んだ部分、図１８の斜線を付した部分、図１９のニで囲んだ部分）に、一部の面同士が重なり合う様に潰れる変形状態が生じる可能性がある。例えば、図１７〜１８に示す構造の場合には、曲げ加工前は、第二連結部４の上面（図１７、１８でＣを付した面）と側壁部２、２の外側面（図１７、１８でＤを付した面）とは、本来同一の仮想平面上に位置している。この為、図１７、１８に示す様に曲げ加工を施した後では、第二連結部４の上面の幅方向両端が各側壁部２、２の外側面にまで達した状態になり、上記第二連結部４のＡ面の長さ方向端部が、側壁部２、２のＢ面の長さ方向端部に覆いかぶさる様に変形して、一部が「重なり」状態となる可能性がある。又、図１９に示す構造の場合も、同様にして、透孔１２の四隅周辺部に重なりが生じる可能性がある。これに対して、側壁部２、２と、両側壁部２、２の連結部３又は第二連結部４との連続部に、重なりを防止する為の段差部を設ける事も従来から考えられているが、この場合には、製品の形状が複雑になったり、製造作業が複雑になる。
In addition, sheet metal rocker arms 48 and 49 as shown in FIGS. 17 to 19 have been conventionally considered as sheet metal rocker arms made of a sheet having a shape different from the element 13a shown in FIG. Yes. In the case of the structures shown in FIGS. 17 to 19, not only the torsional deformation around the four corners of the through-hole 12 occurs, but the torsional deformation further proceeds and a deformation state called “overlap” may occur. is there. That is, the structure of each of these figures is also made by bending the base plate having the through holes 12, but the A located at both ends in the length direction on the inner surface of the through holes 12 before the bending process. After the bending process, the four corners of the through-hole 12 (the part surrounded by c in FIG. 17 and the hatched line in FIG. 18 are the continuous parts of the surface (A surface) marked with B and the surface marked with B (B surface). There is a possibility that a deformed state in which a part of the surfaces are crushed so as to overlap each other may occur in the attached part (the part surrounded by d in FIG. 19). For example, in the case of the structure shown in FIGS. 17 to 18, before bending, the upper surface of the second connecting portion 4 (the surface marked with C in FIGS. 17 and 18) and the outer surfaces of the side walls 2 and 2 (FIG. 17). , 18 and D) are originally located on the same virtual plane. For this reason, after bending as shown in FIGS. 17 and 18, both ends in the width direction of the upper surface of the second connecting portion 4 reach the outer surfaces of the side wall portions 2, 2, There is a possibility that the end in the length direction of the A surface of the two connecting portions 4 is deformed so as to cover the end in the length direction of the B surface of the side walls 2 and 2, and a part thereof is in an “overlapping” state. is there. In the case of the structure shown in FIG. 19 as well, there is a possibility that overlaps occur around the four corners of the through hole 12 in the same manner. On the other hand, it is also conventionally considered to provide a stepped portion for preventing overlap at a continuous portion between the side wall portions 2 and 2 and the connecting portion 3 or the second connecting portion 4 of the side wall portions 2 and 2. In this case, however, the shape of the product becomes complicated and the manufacturing operation becomes complicated.
一方、前述の図１０〜１３に示した従来例の第２例の板金製ロッカーアームの製造方法の場合には、素板１８に１対の側壁部２、２を形成する為の曲げ加工（絞り加工）を行なった後、第一中間素材２１の連結部２２に打ち抜き加工を施して、透孔２３（図１３）を形成している。この為、図２０に誇張して示す様に、この透孔２３の形成後に、側壁部２の内側面（１対の側壁部２同士で互いに対向する面で、図２０の表側面）と透孔２３の内面との間に段差部１６が生じ易くなる。又、上記素板１８に曲げ加工を行なう場合には、図２１に誇張して示す様に、側壁部２の端部で曲げ加工した部分｛図２１（ｂ）の矢印イで示す部分｝に、材料の伸びによる肉ヤセ部が生じたり、側壁部２の内側面で透孔２３の周辺部に、図示しないプレス装置に組み付けた押型の押圧部のＲ部の押し跡である、引けと呼ばれる凹部１７が生じる原因となる。尚、図２１（ａ）では、梨地部分により、押型の抜き後に生じる抜き面を表している。
On the other hand, in the case of the manufacturing method of the sheet metal rocker arm of the second example of the conventional example shown in FIGS. 10 to 13 described above, the bending process for forming the pair of side wall portions 2 and 2 on the base plate 18 (see FIG. After performing the drawing process, the connecting portion 22 of the first intermediate material 21 is punched to form a through hole 23 (FIG. 13). For this reason, as shown exaggeratedly in FIG. 20, after the formation of the through hole 23, the inner side surface of the side wall portion 2 (the surface opposite to each other between the pair of side wall portions 2 and the front side surface of FIG. The step portion 16 is easily generated between the inner surface of the hole 23. Further, when the base plate 18 is bent, as shown exaggeratedly in FIG. 21, a portion bent at the end of the side wall portion 2 {portion indicated by an arrow a in FIG. 21 (b)}. This is called “shrinkage”, which is the result of the material being stretched, or the trace of the R portion of the pressing portion of the pressing die assembled in the pressing device (not shown) on the inner surface of the side wall 2 around the through hole 23. It becomes a cause which the recessed part 17 arises. In FIG. 21 (a), the matte portion represents the punched surface that occurs after the stamping die is punched.
更に、上述の何れの製造方法の場合も、板金製ロッカーアーム１、１ａを構成する金属板の板厚は側壁部２の板厚と同じになる為、金属板の板厚の選択の幅が狭い。例えば、板金製ロッカーアーム１、１ａの軽量化と強度向上とを高次元で両立させるべく、第一連結部３（図１０参照）等の、側壁部２以外の部分の板厚のみを他の部分の板厚よりも大きくしたり、この側壁部２以外の部分の形状を工夫する事を考慮した場合でも、上記金属板の板厚として、この側壁部２以外の部分の好ましい板厚と近いものを選定する事ができず、不都合が生じる。例えば、第一連結部３のみ板厚を特に大きくする事を考えた場合には、この第一連結部３となる部分を大きく増厚する為に、塑性変形量を大きくしなければならない。
Furthermore, in any of the manufacturing methods described above, the thickness of the metal plate constituting the metal plate rocker arms 1 and 1a is the same as the thickness of the side wall portion 2. narrow. For example, in order to achieve both the weight reduction and strength improvement of the metal plate rocker arms 1 and 1a at a high level, only the plate thicknesses of portions other than the side wall portion 2 such as the first connection portion 3 (see FIG. 10) are changed. Even when the thickness of the metal plate is made larger or the shape of the portion other than the side wall portion 2 is taken into consideration, the thickness of the metal plate is close to the preferred thickness of the portion other than the side wall portion 2. Things cannot be selected, causing inconvenience. For example, when it is considered that the thickness of only the first connecting portion 3 is particularly increased, the amount of plastic deformation must be increased in order to greatly increase the thickness of the portion that becomes the first connecting portion 3.
又、従来から、側壁部２の外側面（１対の側壁部２同士で互いに対向しない側の面）に扱き加工を施す事によりこの側壁部２の内側面の形状を整える事も考えられているが、この様に扱き加工を施す場合には、板金製ロッカーアーム１、１ａの材料が大きく流動する為、側壁部２の内側面の形状精度を十分に高くする事が難しくなり、一部にバリが生じる原因ともなる。この為、板金製ロッカーアーム１、１ａの歩留りが悪化する原因となる。
Further, conventionally, it has been considered that the shape of the inner side surface of the side wall portion 2 is adjusted by processing the outer side surface of the side wall portion 2 (the surface on the side where the pair of side wall portions 2 do not face each other). However, in the case of handling in this way, the material of the sheet metal rocker arms 1 and 1a flows greatly, so that it is difficult to sufficiently increase the shape accuracy of the inner side surface of the side wall 2. This also causes burrs. For this reason, the yield of the sheet metal rocker arms 1 and 1a deteriorates.
特開平７−１１９１９号公報JP-A-7-11919
特開２００３−３４３２１５号公報JP 2003-343215 A
本発明は、上述の様な事情に鑑みて、板金製ロッカーアームの側壁部の内側面と透孔の内面との間に段差部が生じたままの状態となる事を防止すると共に、板金製ロッカーアームを構成する金属板の板厚の選択の幅を大きくし、更に、側壁部の内側面の形状精度を安定して高くすべく発明したものである。
In view of the circumstances as described above, the present invention prevents a stepped portion from being left between the inner surface of the side wall portion of the rocker arm made of sheet metal and the inner surface of the through hole, and is made of sheet metal. The invention is invented to increase the selection range of the thickness of the metal plate constituting the rocker arm and to stably increase the shape accuracy of the inner surface of the side wall.
本発明の製造方法の対象となる板金製ロッカーアームは、１枚の金属板を打ち抜き成形する事により、所定の形状を有する素板を形成し、この素板にプレス加工に基づく曲げ加工を施す事により、互いにほぼ平行な１対の側壁部とこれら両側壁部の幅方向一端縁同士を連結する連結部とを形成して成る。そして、これら両側壁部の互いに整合する位置に形成した少なくとも１対の通孔と、上記連結部の一部に設けた、少なくとも１個の係合部とを備える。
そして、本発明の板金製ロッカーアームの製造方法は、上述の様な板金製ロッカーアームを造る際に、上記曲げ加工後に、上記１対の側壁部の内側面にシェービング加工を施す。
The sheet metal rocker arm which is the object of the manufacturing method of the present invention forms a base plate having a predetermined shape by punching and molding a single metal plate, and performs bending processing based on press processing on the base plate. Accordingly, a pair of side wall portions that are substantially parallel to each other and a connecting portion that connects one end edge in the width direction of both side wall portions are formed. And at least 1 pair of through-holes formed in the position where these both side wall parts mutually align, and at least 1 engaging part provided in a part of said connection part are provided.
And the manufacturing method of the sheet metal rocker arm of the present invention performs shaving on the inner side surfaces of the pair of side wall portions after the bending process when producing the sheet metal rocker arm as described above.
上述の様に構成する本発明の板金製ロッカーアームの製造方法によれば、ローラを収容すべく打ち抜き加工により形成した透孔の内面と側壁部の内側面との間に段差部が生じたままの状態となる事を防止できる。又、板金製ロッカーアームを構成する金属板の板厚の選択の幅を大きくできると共に、各側壁部の内側面の形状精度を安定して高くできる。即ち、本発明の板金製ロッカーアームの製造方法によれば、次の様な優れた効果を得られる。
（１） １対の側壁部を形成する為の曲げ加工に伴い、これら各側壁部の一部に厚さが減少する肉ヤセ部や、側壁部の内側面に押型の押圧部のＲ部の押し跡による、引け部と呼ばれる凹部が生じた場合でも、上記肉ヤセ部及び凹部を、何れもシェービング加工により除去できる。又、上記１対の側壁部と連結部とを有する中間素材を造った後、この中間素材の連結部に打ち抜き加工を施す事により透孔を形成するのに伴って、側壁部の内側面と透孔の内面との間に段差部が生じた場合でも、この段差部を上記シェービング加工により除去できる。この為、段差部が生じない良好な形状の側壁部の内側面を得る事ができる。
（２） 両側壁部の内側面にシェービング加工を施す事により、これら両側壁部の、少なくとも一部の板厚を小さく（薄く）できる。この為、板金製ロッカーアームを構成する金属板の板厚を選定する場合に、完成品での側壁部の一部の板厚よりも大きいものを選定できる。この場合でも、側壁部の一部の板厚は小さくできる為、軽量化を特に妨げる原因とはならない。この為、上記金属板の板厚の選択の幅を大きくできる。又、板金製ロッカーアームの強度向上と軽量化とを高次元で両立させる事を考慮した場合や、係合部等の側壁部以外の部分の形状に応じた好ましい板厚と近いものを選択する場合に有利になる。例えば、板金製ロッカーアームの強度向上と軽量化とを高次元で両立させるべく、連結部のみ特に板厚を大きくする場合でも、上記金属板の板厚を大きくできる為、増厚の為の加工を行ない易くなる。
（３） シェービング加工により、素材のうちの少ない取り代分を剪断的に除去できる為、材料の流動を少なくできると共に、加工時に材料に加わる荷重を小さくでき、変形を抑えるか、又はなくす事ができる。この為、各側壁部の外側面に扱き加工を施す事により、これら各側壁部の内側面の形状を整える場合よりも、各側壁部の内側面の形状精度を安定して高くできる。
According to the method for manufacturing a sheet metal rocker arm of the present invention configured as described above, a stepped portion remains between the inner surface of the through hole formed by punching to accommodate the roller and the inner surface of the side wall portion. Can be prevented. In addition, it is possible to increase the selection range of the thickness of the metal plate constituting the metal plate rocker arm, and to stably increase the shape accuracy of the inner side surface of each side wall portion. That is, according to the sheet metal rocker arm manufacturing method of the present invention, the following excellent effects can be obtained.
(1) With the bending process for forming a pair of side wall portions, the thickness of the side wall portions is reduced, or the inner surface of the side wall portions has an R portion of the pressing portion of the pressing die. Even when a concave portion called a shrinkage portion is generated due to the imprint, both the meat shank portion and the concave portion can be removed by shaving. In addition, after the intermediate material having the pair of side wall portions and the connecting portion is made, the through hole is formed by punching the connecting portion of the intermediate material, Even when a stepped portion is formed between the inner surface of the through hole, the stepped portion can be removed by the shaving process. For this reason, it is possible to obtain an inner side surface of the side wall portion having a good shape without a stepped portion.
(2) By shaving the inner side surfaces of both side wall portions, at least some of the plate thicknesses of these both side wall portions can be reduced (thin). For this reason, when selecting the thickness of the metal plate constituting the metal plate rocker arm, it is possible to select a thickness larger than the thickness of a part of the side wall portion of the finished product. Even in this case, since the thickness of a part of the side wall portion can be reduced, it does not cause any particular obstacle to weight reduction. For this reason, the range of selection of the plate thickness of the metal plate can be increased. Also, when considering the improvement of strength and weight reduction of the sheet metal rocker arm at a high level, select a sheet thickness close to the preferred thickness according to the shape of the portion other than the side wall portion such as the engaging portion. Be advantageous in case. For example, in order to achieve both high strength and light weight of the rocker arm made of sheet metal, the thickness of the metal plate can be increased even when the thickness of only the connecting part is increased. It becomes easy to do.
(3) Since the shaving process can remove a small part of the material in a shearing manner, the flow of the material can be reduced, the load applied to the material during processing can be reduced, and deformation can be suppressed or eliminated. it can. For this reason, when the outer surface of each side wall portion is treated, the shape accuracy of the inner side surface of each side wall portion can be stably increased as compared with the case where the shape of the inner side surface of each side wall portion is adjusted.
本発明を実施する場合に好ましくは、素板にプレス加工に基づく曲げ加工を施す事により、１対の側壁部と連結部とを有する中間素材を造った後に、この中間素材の連結部に打ち抜き加工を施す事により透孔を形成し、その後に上記１対の側壁部の内側面にシェービング加工を施す。
この好ましい構成によれば、上記透孔の四隅周辺部に捩れ変形が発生する事を抑える事ができる。この為、板金製ロッカーアームの亀裂等の損傷や重なりの発生を有効に防止でき、歩留りの向上を図れる。
In the case of carrying out the present invention, preferably, an intermediate material having a pair of side wall portions and a connecting portion is made by bending the base plate based on press working, and then punched into the connecting portion of the intermediate material. Through holes are formed by processing, and then shaving is applied to the inner surfaces of the pair of side wall portions.
According to this preferable configuration, it is possible to suppress the occurrence of torsional deformation around the four corners of the through hole. For this reason, it is possible to effectively prevent the occurrence of damage such as cracks and overlap of the rocker arm made of sheet metal, thereby improving the yield.
図１〜２は、本発明の実施例１を示している。これら各図のうち、図１は、本実施例の板金製ロッカーアームの製造方法により製造する、板金製ロッカーアーム１ａの完成品を、図２は、本実施例の製造方法で、透孔２３を有する第二中間素材２４を造った後の工程で、側壁部２の内側面にシェービング加工を施した後の状態を示している。本実施例の特徴は、素板１８（図１１参照）にプレス加工に基づく曲げ加工を施す事により、１対の側壁部２と、これら両側壁部２の幅方向一端縁同士を連結する連結部２２とを有する第一中間素材２１（図１２参照）を造った後、この第一中間素材２１に打ち抜き加工を施す事により透孔２３を有する第二中間素材２４を造り、その後工程で、上記両側壁部２の内側面にシェービング加工を施す点にある。又、このシェービング加工により、側壁部２のうち、長さ方向に関して上記透孔２３と一致する部分の板厚を、連結部３及び第二連結部４の板厚よりも小さく（薄く）している。又、本実施例の場合には、前述の図１０〜１３に示した従来例の第２例の場合と異なり、素板１８の中央部、第一中間素材２１の長さ方向中間部等を図１１、１２の裏側に膨出させる塑性加工を施している。従って、打ち抜き加工により透孔２３を形成した第二中間素材２４及び板金製ロッカーアーム１ａは、側壁部２の図１、２の下部の長さ方向中間部が下方に張り出した形状となっている。その他の板金製ロッカーアーム１ａの構造、並びに、板金製ロッカーアーム１ａを得る為の加工の基本手順に就いては、前述の図１０〜１３に示した従来例の第２例の場合と同様である為、同等部分に関する図示並びに説明は省略若しくは簡略にする。
1 and 2 show Embodiment 1 of the present invention. Among these drawings, FIG. 1 shows a finished product of the sheet metal rocker arm 1a manufactured by the sheet metal rocker arm manufacturing method of this embodiment, and FIG. 2 shows the manufacturing method of this embodiment. A state after the shaving process is performed on the inner side surface of the side wall portion 2 in the step after the second intermediate material 24 having the above is manufactured is shown. A feature of the present embodiment is that the base plate 18 (see FIG. 11) is subjected to a bending process based on a press process to connect a pair of side wall parts 2 and one end edges in the width direction of both side wall parts 2. After making the first intermediate material 21 (see FIG. 12) having the portion 22, the second intermediate material 24 having the through holes 23 is made by punching the first intermediate material 21. The shaving process is performed on the inner side surfaces of the both side wall portions 2. In addition, by this shaving process, the thickness of the side wall portion 2 that matches the through hole 23 in the length direction is made smaller (thinner) than the thickness of the connecting portion 3 and the second connecting portion 4. Yes. In the case of the present embodiment, unlike the case of the second example of the conventional example shown in FIGS. 10 to 13 described above, the central portion of the base plate 18, the intermediate portion in the length direction of the first intermediate material 21, and the like. The plastic working which bulges to the back side of FIG. Therefore, the second intermediate material 24 and the sheet metal rocker arm 1a in which the through holes 23 are formed by punching have a shape in which the lengthwise intermediate portion of the lower side of the side wall portion 2 in FIGS. . The other structure of the metal plate rocker arm 1a and the basic processing procedure for obtaining the metal plate rocker arm 1a are the same as in the second example of the conventional example shown in FIGS. For this reason, illustrations and descriptions of equivalent parts are omitted or simplified.
本実施例の場合には、第二中間素材２４を得るべく第一中間素材２１の連結部２２に打ち抜き加工を施す、第三工程の後に、この第二中間素材２４に、上記両側壁部２の内側面（互いに対向する側面）を削ってこれら両内側面２の寸法精度及び形状精度を向上させる、シェービング加工を施す。この様なシェービング加工を行なう為に、上記第二中間素材２４を図示しないダイセットに設置する。このダイセットは、上記両側壁部２の内側面を削る為のシェービングパンチと、これら両側壁部２を支承すると共にこのシェービングパンチの先端部を受け入れる為の受型とを備える。そして、この受型と上記シェービングパンチとの間に上記第二中間素材２４を設置し、このシェービングパンチを、上記各側壁部２の間部分及び透孔２３の内側部分を通じて、受型に対し遠近動させる事により、これら各側壁部２の内側面の長さ方向中間部で、長さ方向に関して透孔２３と一致する部分を削る。そして、これら各側壁部２の長さ方向中間部の板厚を、第一、第二連結部３、４の板厚よりも小さく（薄く）する。尚、図２（ｂ）に斜格子で示す部分が、上記シェービング加工により削り取った部分を示している。
In the case of the present embodiment, the second intermediate material 24 is punched into the connecting portion 22 of the first intermediate material 21 to obtain the second intermediate material 24. A shaving process is performed to improve the dimensional accuracy and shape accuracy of both inner side surfaces 2 by cutting the inner side surfaces (side surfaces facing each other). In order to perform such a shaving process, the second intermediate material 24 is placed on a die set (not shown). This die set includes a shaving punch for cutting the inner side surfaces of the both side wall portions 2 and a receiving die for supporting the both side wall portions 2 and receiving the leading end portions of the shaving punch. Then, the second intermediate material 24 is installed between the receiving mold and the shaving punch, and the shaving punch is moved away from the receiving mold through the portion between the side walls 2 and the inner portion of the through hole 23. By moving, the portion that coincides with the through hole 23 in the length direction is cut at the intermediate portion in the length direction of the inner side surface of each side wall portion 2. And the plate | board thickness of the length direction intermediate part of each side wall part 2 is made smaller (thinner) than the plate | board thickness of the 1st, 2nd connection parts 3 and 4. FIG. In addition, the part shown by the oblique lattice in FIG.2 (b) has shown the part shaved off by the said shaving process.
上述の様に構成する本実施例の板金製ロッカーアームの製造方法によれば、ローラ６（図５参照）を収容すべく打ち抜き加工により形成した透孔２３の内面と側壁部２、２の内側面との間に段差部１６が生じたままの状態となる事を防止できる。又、板金製ロッカーアーム１ａを構成する金属板の板厚の選択の幅を大きくできると共に、側壁部２、２の内側面の形状精度を安定して高くできる。
即ち、本実施例の板金製ロッカーアームの製造方法によれば、次の様な優れた効果を得られる。
（１） １対の側壁部２を形成する為の曲げ加工に伴い、これら各側壁部２の一部に厚さが減少する肉ヤセ部｛図２１（ｂ）に矢印イで示す部分｝や、側壁部２の内側面に押型の押圧部のＲ部の押し跡による、引け部と呼ばれる凹部１７（図２１参照）が生じた場合でも、上記肉ヤセ部及び凹部１７を、何れもシェービング加工により除去できる。又、上記１対の側壁部２と連結部２２とを有する第一中間素材２１を造った後、この中間素材２１の連結部２２に打ち抜き加工を施す事により透孔２３を形成するのに伴って、側壁部２の内側面と透孔２３の内面との間に段差部１６が生じた場合でも、この段差部１６を上記シェービング加工により除去できる。この為、段差部１６が生じない良好な形状の側壁部２の内側面を得る事ができる。又、この側壁部２の長さ方向中間部の板厚をほぼ均一にできる。
（２） 両側壁部２、２の内側面にシェービング加工を施す事により、これら両側壁部２、２の長さ方向中間部で、長さ方向に関して透孔２３と一致する部分の板厚を小さく（薄く）できる。この為、板金製ロッカーアーム１ａを構成する金属板の板厚を選定する場合に、第一連結部３の板厚等の、完成品での側壁部２、２の長さ方向中間部の板厚よりも大きいものを選定できる。この場合でも、両側壁部２、２の長さ方向中間部の板厚を小さくできる為、軽量化を特に妨げる原因とはならない。この為、上記金属板の板厚の選択の幅を大きくできる。又、板金製ロッカーアーム１ａの強度向上と軽量化とを高次元で両立させる事を考慮した場合や、係合部８や第二の係合部９（図１０参照）等の側壁部２以外の部分の形状に応じた好ましい板厚と近いものを選択する場合に有利になる。例えば、板金製ロッカーアーム１ａの強度向上と軽量化とを高次元で両立させるべく、第一連結部３のみ特に板厚を大きくする場合でも、上記金属板の板厚を大きくできる為、増厚の為の加工を行ない易くなる。
（３） シェービング加工により、第二中間素材２４のうちの少ない取り代分を剪断的に除去できる為、材料の流動を少なくできると共に、加工時に材料に加わる荷重を小さくでき、変形を抑えるか、又はなくす事ができる。この為、各側壁部２、２の外側面に扱き加工を施す事により、これら各側壁部２、２の内側面の形状を整える場合よりも、各側壁部２、２の内側面の形状精度を安定して高くできる。
According to the manufacturing method of the sheet metal rocker arm of the present embodiment configured as described above, the inner surface of the through-hole 23 and the inside of the side wall portions 2 and 2 formed by punching to accommodate the roller 6 (see FIG. 5). It can prevent that the level | step-difference part 16 has arisen between the side surfaces. In addition, it is possible to increase the selection width of the metal plate constituting the metal plate rocker arm 1a, and to stably increase the shape accuracy of the inner side surfaces of the side wall portions 2 and 2.
That is, according to the manufacturing method of the sheet metal rocker arm of the present embodiment, the following excellent effects can be obtained.
(1) As the bending process for forming the pair of side wall parts 2 is performed, the thickness of part of each of the side wall parts 2 is reduced (the part indicated by the arrow A in FIG. 21B) or Even when the concave portion 17 (refer to FIG. 21) called the shrinkage portion is generated on the inner surface of the side wall portion 2 due to the trace of the R portion of the pressing portion of the pressing die, both the shank portion and the concave portion 17 are shaved. Can be removed. Further, after forming the first intermediate material 21 having the pair of side wall portions 2 and the connecting portion 22, the through hole 23 is formed by punching the connecting portion 22 of the intermediate material 21. Even when the step 16 is formed between the inner surface of the side wall 2 and the inner surface of the through hole 23, the step 16 can be removed by the shaving process. For this reason, the inner side surface of the side wall portion 2 having a good shape in which the step portion 16 does not occur can be obtained. Further, the thickness of the intermediate portion in the longitudinal direction of the side wall portion 2 can be made substantially uniform.
(2) By shaving the inner side surfaces of the both side wall portions 2 and 2, the thickness of the portion that coincides with the through hole 23 in the length direction at the intermediate portion in the length direction of the both side wall portions 2 and 2 is set. Can be small (thin). For this reason, when selecting the plate thickness of the metal plate constituting the sheet metal rocker arm 1a, the plate in the intermediate portion in the longitudinal direction of the side wall portions 2 and 2 in the finished product, such as the plate thickness of the first connecting portion 3, etc. A material larger than the thickness can be selected. Even in this case, since the plate thickness of the middle portion in the longitudinal direction of the side wall portions 2 and 2 can be reduced, this does not particularly hinder weight reduction. For this reason, the range of selection of the plate thickness of the metal plate can be increased. In addition, when considering improving the strength and weight reduction of the rocker arm 1a made of sheet metal at a high level, and other than the side wall 2 such as the engaging portion 8 and the second engaging portion 9 (see FIG. 10). This is advantageous when selecting a sheet having a thickness close to the preferred thickness according to the shape of the portion. For example, the thickness of the metal plate can be increased even when only the first connecting portion 3 is made thicker in order to achieve both high strength and light weight in the metal rocker arm 1a. It becomes easy to perform the process for this.
(3) The shaving process can remove a small amount of the second intermediate material 24 in a shearing manner, so that the flow of the material can be reduced and the load applied to the material at the time of processing can be reduced to suppress deformation. Or you can eliminate it. For this reason, the shape accuracy of the inner side surfaces of the side wall portions 2 and 2 is improved by handling the outer side surfaces of the side wall portions 2 and 2, rather than adjusting the shape of the inner side surfaces of the side wall portions 2 and 2. Can be stably increased.
又、本実施例の場合には、所定の外形を有する素板１８（図１１参照）にプレス加工に基づく曲げ加工を施す事により、１対の側壁部２と連結部２２とを有する第一中間素材２１（図１２参照）を造った後に、この第一中間素材２１の連結部２２に打ち抜き加工を施す事により透孔２３を形成し、その後に上記１対の側壁部２の内側面にシェービング加工を施している。この為、前述の図５〜９、１４に示した様な、予め透孔１２を形成した素板１３に曲げ加工を施す事により１対の側壁部２、２と連結部３及び第二連結部４とを有する中間素材１５を造る、従来例の第１例の場合と異なり、上記透孔２３の四隅周辺部に捩れ変形が発生する事を抑える事ができる。従って、板金製ロッカーアーム１ａの亀裂等の損傷や重なりの発生を有効に防止でき、歩留りの向上を図れる。
In the case of the present embodiment, the base plate 18 (see FIG. 11) having a predetermined outer shape is subjected to a bending process based on a press process, whereby the first having the pair of side wall portions 2 and the connecting portion 22. After making the intermediate material 21 (see FIG. 12), a through hole 23 is formed by punching the connecting portion 22 of the first intermediate material 21, and then on the inner surface of the pair of side wall portions 2. Shaving is applied. For this reason, as shown in FIGS. 5 to 9 and 14 described above, a pair of side wall portions 2 and 2 and a connecting portion 3 and a second connecting portion are formed by bending a base plate 13 in which a through-hole 12 has been previously formed. Unlike the case of the first example of the conventional example in which the intermediate material 15 having the portion 4 is formed, it is possible to suppress the occurrence of torsional deformation in the four corners of the through hole 23. Therefore, it is possible to effectively prevent damage such as cracks and overlap of the sheet metal rocker arm 1a, and improve the yield.
次に、図３は、本発明の実施例２を示している。本実施例の場合には、板金製ロッカーアームを、所謂順送加工により造っている。この順送加工を行なう場合には、先ず、図示しないアンコイラから長さ方向（図３の左右方向）に送られる長尺な金属板１０の一部を、図３の（Ｂ）位置でプレス加工により打ち抜く事により、所定の外形を有する素板２５、２５を、打ち抜き後のスケルトン２６（打ち抜き残材）の柱部２７の両側に形成する。尚、上記金属板１０には、図３の（Ａ）位置で、その一部を厚さ方向に押圧して金属材料を隣接部に流動させる加工を施す事により、上記図３の（Ａ）位置に斜格子で示す部分の肉厚を増大させると共に、斜線で示す部分の肉厚を低下させている。
Next, FIG. 3 shows Embodiment 2 of the present invention. In the case of the present embodiment, the rocker arm made of sheet metal is made by so-called progressive processing. When performing this progressive processing, first, a part of the long metal plate 10 fed in the length direction (left and right direction in FIG. 3) from an uncoiler (not shown) is pressed at the position (B) in FIG. The base plates 25 and 25 having a predetermined outer shape are formed on both sides of the column portion 27 of the skeleton 26 (punching remaining material) after punching. Note that the metal plate 10 is subjected to a process of pressing a part thereof in the thickness direction at the position (A) in FIG. The thickness of the portion indicated by the oblique lattice at the position is increased, and the thickness of the portion indicated by the oblique line is reduced.
上記図３の（Ｂ）位置で形成された上記各素板２５、２５は、続く（Ｃ）位置で幅方向（図３の左右方向）両側部分をほぼ直角に、同方向に折り曲げて断面形状を略Ｕ字形とする曲げ加工を施して、第一中間素材２８、２８とする。この曲げ加工は、上記（Ｃ）位置に設置したダイセットに設けた受型と押型との間に上記各素板２５、２５を位置させた状態で、押型を受型に向け押し付ける事により行なう。
Each of the base plates 25, 25 formed at the position (B) in FIG. 3 is bent in the same direction at both sides in the width direction (left and right direction in FIG. 3) at the subsequent position (C). The first intermediate material 28, 28 is formed by bending to a substantially U-shape. This bending process is performed by pressing the pressing die against the receiving die in a state where the base plates 25 and 25 are positioned between the receiving die provided on the die set installed at the position (C) and the pressing die. .
これら両第一中間素材２８、２８には、図３の（Ｄ）位置で、中央部に鼓状の透孔２９を形成する打ち抜き加工を施して、第二中間素材３０、３０とする。この様な透孔２９を形成する為に、上記（Ｄ）位置に、打ち抜き用のパンチと受型とを備えたダイセットを設置しておく。
These first intermediate materials 28 and 28 are punched to form a drum-shaped through hole 29 in the center at the position (D) in FIG. In order to form such a through hole 29, a die set including a punch for punching and a receiving die is installed at the position (D).
上記両第二中間素材３０、３０には、図３の（Ｅ）位置で、上記透孔２９の両側縁からこの透孔２９の中央部に向けて突出した１対の凸円弧状部４６、４６を図３の裏面方向に折り立てて、図３の手前に折り立てられた部分と面一にする（同一平面上に位置させる）扱き加工を施す。そして、互いに平行な１対の側壁部２、２を備えた、第三中間素材３１、３１とする。この様な扱き加工を行なう為に、上記（Ｅ）位置に、上記透孔２９に突き通す扱き用のパンチと、このパンチにより塑性変形させられる上記両凸円弧状部４６、４６を受け入れる受型とを備えたダイセットを設置しておく。
A pair of convex arcuate portions 46 projecting from both side edges of the through hole 29 toward the center of the through hole 29 at the position (E) in FIG. 46 is folded in the direction of the back surface of FIG. 3 to make it flush with the portion folded in front of FIG. 3 (positioned on the same plane). And it is set as the 3rd intermediate material 31 and 31 provided with a pair of side wall parts 2 and 2 parallel to each other. In order to perform such handling processing, at the position (E), a handling punch that penetrates the through hole 29, and a receiving mold that receives the biconvex arc-shaped portions 46, 46 that are plastically deformed by the punch, Install a die set with
上記両第三中間素材３１、３１には、図３の（Ｆ）位置で、上記両側壁部２、２の内側面（互いに対向する側面）を削ってこれら両内側面の寸法精度及び形状精度を向上させる、シェービング加工を施して、第四中間素材３２、３２とする。この様なシェービング加工を行なう為に、上記（Ｆ）位置に、上記両側壁部２、２の内側面を削る為のシェービングパンチと、これら両側壁２、２を支承すると共にこのシェービングパンチの先端部を受け入れる為の受型とを備えたダイセットを設置しておく。
In the third intermediate materials 31 and 31, at the position (F) in FIG. 3, the inner side surfaces (side surfaces facing each other) of the both side wall portions 2 and 2 are shaved, and the dimensional accuracy and shape accuracy of both inner side surfaces are obtained. The fourth intermediate material 32, 32 is obtained by applying a shaving process to improve the quality of the material. In order to perform such a shaving process, at the position (F), a shaving punch for shaving the inner side surfaces of the side walls 2, 2 and the side walls 2, 2 are supported and the tip of the shaving punch A die set equipped with a receiving mold for receiving the part is installed.
上記両第四中間素材３２、３２には、図３の（Ｇ）位置で、これら両第四中間素材３２、３２を、押型と受型から成る、矯正用の金型で押圧して形状を整える整形加工を施して、第五中間素材３３、３３とする。上記第四中間素材３２、３２を上記第五中間素材３３、３３とするには、これら第四中間素材３２、３２を上記押型と受型との間で押圧して、形状を整える。
The above-mentioned fourth intermediate materials 32, 32 are pressed at the position (G) in FIG. 3 by pressing the both intermediate materials 32, 32 with a correction die comprising a pressing die and a receiving die. The fifth intermediate material 33, 33 is formed by performing shaping processing. In order to make the fourth intermediate materials 32 and 32 the fifth intermediate materials 33 and 33, the fourth intermediate materials 32 and 32 are pressed between the pressing mold and the receiving mold to adjust the shape.
上記両第五中間素材３３、３３には、図３の（Ｈ）位置で、上記両側壁部２、２同士の間部分に設けられた連結部３及び第二連結部４に、係合部８及び第二係合部９を形成する塑性加工を施して、第六中間素材３４、３４とする。これら両係合部６、７を形成する為、上記（Ｈ）位置に、第五中間素材３３、３３毎に１対の押部を備えた押型と、同じく１対の受部を備えた受型とから成る、塑性加工用の金型を備えた、ダイセットを設置しておく。上記第五中間素材３３、３３を上記第六中間素材３４、３４とするには、これら第五中間素材３３、３３のうちの連結部３及び第二連結部４を上記押型と受型との間で押圧して、これら両連結部３、４に上記両係合部６、７を形成する。
In the fifth intermediate material 33, 33, the engaging portion is connected to the connecting portion 3 and the second connecting portion 4 provided at the portion between the both side wall portions 2, 2 at the position (H) in FIG. 8 and the second engaging portion 9 are subjected to plastic working to form sixth intermediate materials 34 and 34. In order to form both the engaging portions 6 and 7, at the position (H), a pressing die having a pair of pressing portions for each of the fifth intermediate materials 33 and 33 and a receiving portion having a pair of receiving portions are also provided. A die set including a mold for plastic working is installed. In order to make the fifth intermediate material 33, 33 the sixth intermediate material 34, 34, the connecting portion 3 and the second connecting portion 4 of the fifth intermediate materials 33, 33 are connected to the pressing die and the receiving die. The two engaging portions 6 and 7 are formed on the connecting portions 3 and 4 by pressing between them.
上記両第六中間素材３４、３４には、図３の（Ｉ）位置で、上記両側壁部２、２の互いに整合する位置に通孔５、５を形成する打ち抜き加工を施して、第七中間素材３５、３５とする。
そして、最後に、上記両第七中間素材３５、３５を、図３の（Ｊ）位置で、前記スケルトン２６の柱部２７から（切断線α部分で）切り離して、板金製ロッカーアーム１ａを得る。
Both the sixth intermediate materials 34, 34 are punched to form through holes 5, 5 at the positions where the both side walls 2, 2 are aligned with each other at the position (I) in FIG. Intermediate materials 35 and 35 are used.
Finally, both the seventh intermediate materials 35, 35 are separated from the column portion 27 of the skeleton 26 (at the cutting line α portion) at the position (J) in FIG. 3 to obtain the sheet metal rocker arm 1a. .
上述の様な順送加工により上記板金製ロッカーアーム１ａを造る本実施例の場合も、前述の実施例１の場合と同様に、透孔２９の内面と側壁部２、２の内側面との間に段差部１６（図２０参照）が生じたままの状態となる事を防止できる。又、板金製ロッカーアーム１ａを構成する金属板１０の板厚の選択の幅を大きくできると共に、側壁部２、２の内側面の形状精度を安定して高くできる。又、本実施例の場合も、第一連結部３の増厚の為の加工を行ない易くなる。
その他の構成及び作用に就いては、前述の実施例１の場合と同様である為、同等部分に関する説明は省略する。
In the case of the present embodiment in which the sheet metal rocker arm 1a is manufactured by progressive processing as described above, the inner surface of the through-hole 29 and the inner surfaces of the side wall portions 2 and 2 are formed in the same manner as in the first embodiment. It can prevent that the level | step-difference part 16 (refer FIG. 20) remains in the middle. In addition, it is possible to increase the selection range of the thickness of the metal plate 10 constituting the sheet metal rocker arm 1a, and to stably increase the shape accuracy of the inner side surfaces of the side walls 2 and 2. Also in this embodiment, it becomes easy to perform processing for increasing the thickness of the first connecting portion 3.
Other configurations and operations are the same as those in the first embodiment described above, and thus the description of the equivalent parts is omitted.
次に、図４は、本発明の実施例３を示している。本実施例の場合には、上述の図３に示した実施例２の場合と異なり、板金製ロッカーアーム１ａの製造時に、長尺な金属板１０の送り方向と、素板３６及び各加工段階の中間素材３７〜４３の長さ方向とを一致させている。又、これら素板３６及び中間素材３７〜４３を、上記送り方向に関して互いに直列に配置している。即ち、本実施例の場合、図示しないアンコイラから長さ方向（図４の左右方向）に送られる長尺な金属板１０の一部を、図４の（Ｂ）位置でプレス加工により打ち抜く事により、所定の外形を有する素板３６を、打ち抜き後のスケルトン４４の幅方向（図４の上下方向）中央部に形成する。この素板３６と、上記金属板１０及び後述する各中間素材３７〜４３とは、それぞれの幅方向中央部同士を、この金属板１０の打ち抜き残部である、幅狭部４５、４５により連結している。即ち、この金属板１０と、上記素板３６と、上記各中間素材３７〜４３とは、これら素板３６及び各中間素材３７〜４３の長さ方向に関する、上記金属板１０の送り方向（図４の左右方向）に関して、互いに直列に、互いに等しいピッチＰで結合している。上記金属板１０を上記板金製ロッカーアーム１ａに加工する際には、この金属板１０と、上記素板３６と、上記各中間素材３７〜４３とを、上記ピッチＰ分ずつ、間欠的に（加工の為の停止を繰り返しつつ）送る。尚、上記金属板１０には、図４の（Ａ）位置で、その一部を厚さ方向に押圧して金属材料を隣接部に流動させる加工を施す事により、上記図４の（Ａ）位置に斜格子で示す部分の肉厚を増大させると共に、斜線で示す部分の肉厚を低下させている。
Next, FIG. 4 shows Embodiment 3 of the present invention. In the case of the present embodiment, unlike the case of the second embodiment shown in FIG. 3 described above, the feeding direction of the long metal plate 10, the base plate 36, and each processing stage are produced during the manufacture of the rocker arm 1 a made of sheet metal. The lengths of the intermediate materials 37 to 43 are made to coincide with each other. The base plate 36 and the intermediate materials 37 to 43 are arranged in series with respect to the feeding direction. That is, in the case of the present embodiment, by punching a part of the long metal plate 10 sent from an uncoiler (not shown) in the length direction (left and right direction in FIG. 4) at the position (B) in FIG. The base plate 36 having a predetermined outer shape is formed at the center in the width direction (vertical direction in FIG. 4) of the skeleton 44 after punching. The base plate 36, the metal plate 10 and each of the intermediate materials 37 to 43 to be described later are connected to each other in the center in the width direction by narrow portions 45 and 45, which are punching remaining portions of the metal plate 10. ing. That is, the metal plate 10, the base plate 36, and the intermediate materials 37 to 43 are related to the length direction of the base plate 36 and the intermediate materials 37 to 43. 4 in the left-right direction), and they are coupled in series with each other at an equal pitch P. When the metal plate 10 is processed into the sheet metal rocker arm 1a, the metal plate 10, the base plate 36, and the intermediate materials 37 to 43 are intermittently separated by the pitch P ( Sending while repeatedly stopping for processing). The metal plate 10 is subjected to a process of pressing a part thereof in the thickness direction at the position (A) in FIG. The thickness of the portion indicated by the oblique lattice at the position is increased, and the thickness of the portion indicated by the oblique line is reduced.
上記図４の（Ｂ）位置で形成された上記素板３６は、上記ピッチＰ分だけ後方（図４の右方）に送って、図４の（Ｃ）位置で停止させる。そして、この（Ｃ）位置で上記素板３６に、幅方向（図３の左右方向）両側部分をほぼ直角に、同方向に折り曲げて断面形状を略Ｕ字形とする曲げ加工を施して、第一中間素材３７とする。
The base plate 36 formed at the position (B) in FIG. 4 is sent rearward (to the right in FIG. 4) by the pitch P and stopped at the position (C) in FIG. Then, at the position (C), the base plate 36 is subjected to a bending process in which both side portions in the width direction (left-right direction in FIG. 3) are bent at substantially right angles in the same direction so that the cross-sectional shape is substantially U-shaped. One intermediate material 37 is used.
上記第一中間素材３７には、図４の（Ｄ）位置で、中央部に鼓状の透孔２９を形成する打ち抜き加工を施して、第二中間素材３８とする。
又、この第二中間素材３８には、図４の（Ｅ）位置で、上記透孔２９の両側縁からこの透孔２９の中央部に向けて突出した１対の凸円弧状部４６、４６を図４の裏面方向に折り立てて、図４の手前に折り立てられた部分と面一にする（同一平面上に位置させる）扱き加工を施す。そして、互いに平行な１対の側壁部２、２を備えた、第三中間素材３９とする。
The first intermediate material 37 is punched to form a drum-shaped through hole 29 in the center at the position (D) in FIG.
Further, the second intermediate material 38 has a pair of convex arc-shaped portions 46, 46 projecting from both side edges of the through hole 29 toward the center of the through hole 29 at the position (E) of FIG. 4 is folded in the direction of the back surface of FIG. 4 so as to be flush with the portion folded in front of FIG. 4 (positioned on the same plane). And it is set as the 3rd intermediate raw material 39 provided with a pair of side wall parts 2 and 2 parallel to each other.
この第三中間素材３１には、図４の（Ｆ）位置で、上記両側壁部２、２の内側面（互いに対向する側面）を削ってこれら両内側面の寸法精度及び形状精度を向上させる、シェービング加工を施して、第四中間素材４０とする。
この第四中間素材４０には、図４の（Ｇ）位置で、この第四中間素材４０を矯正用の金型で押圧して形状を整える整形加工を施して、第五中間素材４１とする。
この第五中間素材４１には、図４の（Ｈ）位置で、上記両側壁部２、２同士の間部分に設けた連結部３及び第二連結部４に、係合部８及び第二係合部９を形成する塑性加工を施して、第六中間素材４２とする。
この第六中間素材４２には、図４の（Ｉ）位置で、上記両側壁部２、２の互いに整合する位置に通孔５、５を形成する打ち抜き加工を施して、第七中間素材４３とする。
そして、最後に、上記第七中間素材４３を、図４の（Ｊ）位置で、前記スケルトン４４の幅狭部４５から（切断線α部分で）切り離して、板金製ロッカーアーム１ａを得る。
In the third intermediate material 31, at the position (F) in FIG. 4, the inner side surfaces (side surfaces facing each other) of the both side walls 2 and 2 are shaved to improve the dimensional accuracy and shape accuracy of both inner side surfaces. The fourth intermediate material 40 is formed by shaving.
The fourth intermediate material 40 is subjected to a shaping process for adjusting the shape by pressing the fourth intermediate material 40 with a correction mold at the position (G) in FIG. .
In the fifth intermediate material 41, at the position (H) in FIG. 4, the engaging portion 8 and the second connecting portion 3 are connected to the connecting portion 3 and the second connecting portion 4 provided in the portion between the both side wall portions 2, 2. The sixth intermediate material 42 is formed by plastic processing for forming the engaging portion 9.
The sixth intermediate material 42 is punched to form through holes 5 and 5 at positions where the side walls 2 and 2 are aligned with each other at the position (I) in FIG. And
Finally, the seventh intermediate material 43 is separated from the narrow portion 45 of the skeleton 44 (at the cutting line α portion) at the position (J) in FIG. 4 to obtain a sheet metal rocker arm 1a.
上述の様に構成する本実施例の板金製ロッカーアームの製造方法によれば、各工程で、素板３６及び中間素材３７〜４３を、長尺な金属板１０に繋った状態のまま、この金属板１０の送り方向に移送する為、上記各工程での、上記素板３６及び中間素材３７〜４３の金型内への送り込みやこの金型からの取り出し作業を容易に行なえる。又、上記素板３６及び中間素材３７〜４３のそれぞれの長さ方向を長尺な金属板１０の送り方向に一致させて、これら素板３７及び中間素材３７〜４３を、この送り方向に関して互いに直列に配置している。この為、上述の図３に示した実施例２の場合と異なり、隣り合う素板３６と中間素材３７との間、或は隣り合う中間素材３７〜４３同士の間に金型を配置する必要がない。この為、金型を配置する為のスペース確保の為に、隣り合う素板３６と中間素材３７〜４３とのピッチＰ、及び、隣り合う中間素材３７〜４３同士のピッチＰを大きくする必要がない。そして、このピッチＰを小さく抑えられる分、上記金属板１０から打ち抜かれる廃材の割合を少なくして（材料の無駄を少なくして）、材料費の低減を図れる。
その他の構成及び作用に就いては、上述の図３に示した実施例２の場合と同様である為、重複する説明は省略する。
尚、上述の図３〜４に示した実施例２、３の場合には、第一中間素材２８、３７に打ち抜き加工を施す事により鼓状の透孔２９を形成し、１対の凸円弧状部４６、４６が形成される様にしている。そしてこの構成により、完成後の板金製ロッカーアーム１ａで側壁部２、２の長さ方向中間部が図３〜４の裏側に張り出す様にしている。但し、これら各実施例２、３で、透孔２９を形成する以前に、金属板１０、素板２５、３６等の各凸円弧状部４６、４６に対応する部分を、図３〜４の裏側に膨出させる塑性加工を施す事もできる。
According to the sheet metal rocker arm manufacturing method of the present embodiment configured as described above, the base plate 36 and the intermediate materials 37 to 43 are connected to the long metal plate 10 in each step. Since the metal plate 10 is transferred in the feeding direction, the base plate 36 and the intermediate materials 37 to 43 can be easily fed into the mold and taken out from the mold in each step. Further, the length directions of the base plate 36 and the intermediate materials 37 to 43 are made to coincide with the feed direction of the long metal plate 10, and the base plate 37 and the intermediate materials 37 to 43 are mutually connected with respect to the feed direction. They are arranged in series. For this reason, unlike the case of the second embodiment shown in FIG. 3 described above, it is necessary to dispose a mold between the adjacent base plate 36 and the intermediate material 37 or between the adjacent intermediate materials 37 to 43. There is no. For this reason, it is necessary to increase the pitch P between the adjacent base plate 36 and the intermediate materials 37 to 43 and the pitch P between the adjacent intermediate materials 37 to 43 in order to secure a space for placing the mold. Absent. And since this pitch P can be kept small, the ratio of the waste material punched out from the metal plate 10 can be reduced (material waste is reduced), and the material cost can be reduced.
Since other configurations and operations are the same as those of the second embodiment shown in FIG. 3 described above, a duplicate description is omitted.
In the case of Examples 2 and 3 shown in FIGS. 3 to 4 described above, a drum-shaped through hole 29 is formed by punching the first intermediate material 28 and 37 to form a pair of convex circles. Arc-shaped portions 46 and 46 are formed. And by this structure, the length direction intermediate part of the side wall parts 2 and 2 is projected over the back side of FIGS. However, in these Examples 2 and 3, before forming the through holes 29, the portions corresponding to the convex arc-shaped portions 46 and 46 such as the metal plate 10 and the base plates 25 and 36 are shown in FIGS. Plastic working that bulges to the back side can also be performed.
本発明の実施例１の製造方法により製造する、板金製ロッカーアームの斜視図。The perspective view of the rocker arm made from a sheet metal manufactured with the manufacturing method of Example 1 of this invention.
透孔の打ち抜き加工後に側壁部の内側面にシェービング加工を施した後の状態を示しており、（ａ）は部分拡大斜視図、（ｂ）は（ａ）のＡ−Ａ断面図。The state after giving the shaving process to the inner surface of a side wall part after the punching process of a through-hole is shown, (a) is a partial expanded perspective view, (b) is AA sectional drawing of (a).
本発明の実施例２を示す、各工程でのプレス加工を施されたスケルトンの平面図。The top view of the skeleton which gave the press work in each process which shows Example 2 of this invention.
同実施例３を示す、図３と同様の図。The figure similar to FIG. 3 which shows the same Example 3. FIG.
板金製ロッカーアームの従来構造の第１例を示す斜視図。The perspective view which shows the 1st example of the conventional structure of a rocker arm made from sheet metal.
この板金製ロッカーアームの製造方法の従来例の第１例の第一工程により得られる金属板を示しており、（ａ）は平面図、（ｂ）は（ａ）のＢ−Ｂ断面図。The metal plate obtained by the 1st process of the 1st example of the prior art example of the manufacturing method of this sheet metal rocker arm is shown, (a) is a top view and (b) is a BB sectional view of (a).
同第二工程により得られる素板を示しており、（ａ）は平面図、（ｂ）は（ａ）のＣ−Ｃ断面図。The base plate obtained by the said 2nd process is shown, (a) is a top view, (b) is CC sectional drawing of (a).
同第三工程により得られる中間素材を示しており、（ａ）は平面図、（ｂ）は（ａ）のＤ−Ｄ断面図。The intermediate material obtained by the said 3rd process is shown, (a) is a top view, (b) is DD sectional drawing of (a).
同第四工程により得られる第二中間素材を示しており、（ａ）は平面図、（ｂ）は（ａ）のＥ−Ｅ断面図。The 2nd intermediate material obtained by the 4th process is shown, (a) is a top view and (b) is an EE sectional view of (a).
板金製ロッカーアームの従来構造の第２例を示しており、（ａ）は平面図、（ｂ）は（ａ）のＡ−Ａ断面図、（ｃ）は（ａ）のＢ−Ｂ断面図、（ｄ）は（ａ）のＣ−Ｃ断面図。The 2nd example of the conventional structure of a sheet metal rocker arm is shown, (a) is a top view, (b) is an AA sectional view of (a), (c) is a BB sectional view of (a). , (D) is CC sectional drawing of (a).
この板金製ロッカーアームの製造方法の従来例の第２例の第一工程により得られる素板を示しており、（ａ）は平面図、（ｂ）は（ａ）のＦ−Ｆ断面図。The base plate obtained by the 1st process of the 2nd example of the prior art example of the manufacturing method of this sheet metal rocker arm is shown, (a) is a top view and (b) is an FF sectional view of (a).
同第二工程により得られる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、（ｃ）は（ａ）のＢ−Ｂ断面図、（ｄ）は（ａ）のＣ−Ｃ断面図。The 1st intermediate material obtained by the said 2nd process is shown, (a) is a top view, (b) is AA sectional drawing of (a), (c) is BB sectional drawing of (a). , (D) is CC sectional drawing of (a).
同第三工程により得られる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、（ｃ）は（ａ）のＢ−Ｂ断面図、（ｄ）は（ａ）のＣ−Ｃ断面図。The 2nd intermediate material obtained by the said 3rd process is shown, (a) is a top view, (b) is AA sectional drawing of (a), (c) is BB sectional drawing of (a). , (D) is CC sectional drawing of (a).
板金製ロッカーアームの製造方法の従来例の第１例に於ける不都合を説明する為の、図９（ｂ）の下方から見た部分拡大斜視図。FIG. 10 is a partially enlarged perspective view seen from below in FIG. 9B for explaining inconveniences in the first example of the conventional example of the manufacturing method of the sheet metal rocker arm.
この不都合をより詳しく説明する為の素板の別形状の斜視図。The perspective view of another shape of the base plate for explaining this inconvenience in more detail.
図１５に示した素板に曲げ加工を施す事により得られる中間素材を示す斜視図。The perspective view which shows the intermediate material obtained by performing a bending process to the base plate shown in FIG.
曲げ加工により重なりが生じる事を説明する為の板金製ロッカーアームの従来例の別形状の第１例を示す斜視図。The perspective view which shows the 1st example of another shape of the prior art example of the rocker arm made from a sheet metal for demonstrating that overlap arises by bending.
図１７の部分拡大図。The elements on larger scale of FIG.
曲げ加工により重なりが生じる事を説明する為の板金製ロッカーアームの従来例の別形状の第２例を示す斜視図。The perspective view which shows the 2nd example of another shape of the prior art example of the rocker arm made from a sheet metal for demonstrating that overlap arises by bending.
板金製ロッカーアームの製造方法の従来例の第２例に於ける不都合を説明する為の、図１３（ｂ）の上方から見た部分拡大斜視図。FIG. 14 is a partially enlarged perspective view as viewed from above in FIG. 13B for explaining inconveniences in the second example of the conventional example of the manufacturing method of the sheet metal rocker arm.
同じく別の不都合を説明する為の、（ａ）は図１３（ｂ）の上方から見た部分拡大斜視図、（ｂ）は（ａ）のＧ−Ｇ断面図。Similarly, (a) is a partially enlarged perspective view seen from above in FIG. 13 (b), and (b) is a GG cross-sectional view of (a) for explaining another inconvenience.
符号の説明Explanation of symbols
１、１ａ 板金製ロッカーアーム
２ 側壁部
３ 連結部
４ 第二連結部
５ 通孔
６ ローラ
７ 支持軸
８ 係合部
９ 第二係合部
１０ 金属板
１１ 壁部形成用凹部
１２ 透孔
１３、１３ａ 素板
１４ 凸円弧状部
１５、１５ａ 中間素材
１６ 段差部
１７ 凹部
１８ 素板
１９ 基部
２０ 翼状部
２１ 第一中間素材
２２ 連結部
２３ 透孔
２４ 第二中間素材
２５ 素板
２６ スケルトン
２７ 柱部
２８ 第一中間素材
２９ 透孔
３０ 第二中間素材
３１ 第三中間素材
３２ 第四中間素材
３３ 第五中間素材
３４ 第六中間素材
３５ 第七中間素材
３６ 素板
３７ 第一中間素材
３８ 第二中間素材
３９ 第三中間素材
４０ 第四中間素材
４１ 第五中間素材
４２ 第六中間素材
４３ 第七中間素材
４４ スケルトン
４５ 幅狭部
４６ 凸円弧状部
４７ 第二中間素材
４８ 板金製ロッカーアーム
４９ 板金製ロッカーアーム
DESCRIPTION OF SYMBOLS 1, 1a Sheet metal rocker arm 2 Side wall part 3 Connection part 4 Second connection part 5 Through-hole 6 Roller 7 Support shaft 8 Engagement part 9 Second engagement part 10 Metal plate 11 Wall part formation recessed part 12 Through-hole 13, 13a Base plate 14 Convex arc-shaped portion 15, 15a Intermediate material 16 Stepped portion 17 Recessed portion 18 Base plate 19 Base portion 20 Wing-like portion 21 First intermediate material 22 Connecting portion 23 Through hole 24 Second intermediate material 25 Base plate 26 Skeleton 27 Column portion 28 First intermediate material 29 Through hole 30 Second intermediate material 31 Third intermediate material 32 Fourth intermediate material 33 Fifth intermediate material 34 Sixth intermediate material 35 Seventh intermediate material 36 Base plate 37 First intermediate material 38 Second intermediate Material 39 Third intermediate material 40 Fourth intermediate material 41 Fifth intermediate material 42 Sixth intermediate material 43 Seventh intermediate material 44 Skeleton 45 Narrow part 46 Convex arcuate part 47 Second intermediate material 4 8 Sheet metal rocker arm 49 Sheet metal rocker arm
