JPS5919778B2 - Manufacturing method for motorcycle fenders - Google Patents

Description

【発明の詳細な説明】 本発明は自動二輪車用フエンダの製造方法に関するもの
である。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a fender for a motorcycle.

自動二輪車用フエンダの製造は従来ではプレス絞り成形
法、冷間ロール成形法、或はダイインタプレス成形法で
成形され、更に近時ではストレッチベンド成形法も提案
されている。Fenders for motorcycles have conventionally been manufactured by press drawing, cold roll forming, or die interpress forming, and recently, stretch bend forming has also been proposed.

プレス絞り成形法は、金属薄板素材を絞り成形で周辺に
余片を延出させた湾曲樋状に成形して中間素材を得、次
いで余片をカーリング用フランジ代を残してトリミング
し、更に素材の全周にカーリング部を形成し、最終工程
でステー取付用の孔をピアス加工して製品を得る。In the press drawing method, an intermediate material is obtained by drawing a thin metal sheet material into a curved gutter shape with a surplus extending around the periphery, and then the remaining material is trimmed leaving a flange allowance for curling. A curling part is formed around the entire circumference, and in the final step, a hole for attaching the stay is pierced to obtain the product.

かかる成形法は、金属薄板を略半円弧状に絞り加工する
ため製品表面となる部分を成形ビード及びメス型角ダイ
で擦りつつ成形するさいのショックライン、絞り傷が発
生し、素材四隅部に相当する部分の製品形状に圧縮応力
が作用してシワが発生し易く、この金属板の中央を境に
して外側には引張応力が、又内側には収縮応力が作用し
てスプリングバックが発生し、外観を損ねるという欠点
がある。In this forming method, the thin metal plate is drawn into a roughly semicircular arc shape, so shock lines and drawing scratches occur during forming while rubbing the surface of the product with a forming bead and a female square die, resulting in damage to the four corners of the material. Compressive stress acts on the product shape in the corresponding area, which tends to cause wrinkles, and tensile stress acts on the outside of the metal plate, and shrinkage stress acts on the inside, causing springback. , which has the disadvantage of spoiling the appearance.

ために爾後パラ仕上等の作業を必要とし、この作業も湾
曲面に行う必要があつて作業が面倒、煩雑であり、又熟
練を必要とし、更に皿面全周に仕上加工を施したりした
場合には作業は一層面９Ｌ煩雑となる。そして工程上も
ドロー、トリム、ベンド４工程、ピアス、カール２工程
、更にフォーム等の多工程を必要とし、作業性が悪く、
又絞り成形後のカーリング加工はニプラーによる手作業
工程となり、生産性が劣り、材料の歩留りも悪く、材料
経済上も好ましくない。ダイインタプレス成形法による
フエンダの製造も同様のシワ、スプリングバック、傷等
が発生し、外観性を損ねるという欠点があり、工程も前
記と同様にドロー、トリムピアス、カーリング、Ｕ曲、
ダイインタマシンによる先端成形、全体成形等の工程を
必要とし、面倒な作業を必要とする等前記と同様の問題
がある。Therefore, work such as para-finishing is required afterwards, and this work also needs to be done on a curved surface, which is troublesome and complicated, and requires skill.In addition, when finishing is performed on the entire circumference of the dish surface. The work becomes even more complicated. In addition, the process requires multiple steps such as draw, trim, bend (4 steps), piercing, curl (2 steps), and foaming, which is difficult to work with.
Further, the curling process after drawing is a manual process using a nippler, resulting in poor productivity and poor material yield, which is also unfavorable in terms of material economy. Manufacturing fenders using the die-interpress molding method also has the disadvantage that similar wrinkles, springback, and scratches occur, impairing the appearance.
It requires processes such as tip molding and overall molding using a die intermachine, and has the same problems as above, such as requiring troublesome work.

又冷間ロール成形法によるフエンダの製造法は、金属薄
板の両側をカーリング加工し、この素材をロール成形し
、爾後フエンダ形状に裁断加工し、次にフエンダ素材の
前後端部をカーリング加工する。Furthermore, in the method of manufacturing a fender by cold roll forming, both sides of a thin metal plate are curled, this material is roll-formed, and then cut into a fender shape, and then the front and rear ends of the fender material are curled.

かかる成形法はロール成形によりスプリングバックを生
じ、製品を高精度に維持することが難かしく、ロール成
形後に素材前後端部のカーリング加工等の端末処理は両
側のカーリング部との不連続を生じ、安全上、外観上好
ましくない上、処理工数が増え、又半円弧状の成形品に
端末処理を行う等生産性が悪い等の欠点がある。This forming method causes springback due to roll forming, making it difficult to maintain high precision of the product, and end treatments such as curling of the front and rear ends of the material after roll forming cause discontinuity with the curled parts on both sides. In addition to being unfavorable in terms of safety and appearance, it also increases the number of processing steps and has drawbacks such as poor productivity due to terminal treatment of semicircular arc-shaped molded products.

更に最近の成形法としてストレッチフォーム成形法が提
案されるが、これは金属薄板をフエンダの展開形状に打
抜いてこの素材両側縁部等をカーリング成形し、次に素
材断面形状をＵ字状に成形してこれをストレッチベンド
機で引張作用を与えながら略半円弧状に成形し、最後に
ステー取付孔をピアス加工等で成形するもので、工程と
してはブランク、フォーム、カーリング、りストライク
、Ｕ曲、ストレッチフォーム、ピアス等の各工程を必要
とし、高精度のフエンダを効率良く、且つ安価に製造す
ることができるものであるが、未だ工程数も多く、作業
工数も多くかかるという問題がある。Furthermore, a stretch foam molding method has been proposed as a recent molding method, in which a thin metal plate is punched out into the expanded shape of a fender, the edges on both sides of the material are curled, and then the cross-sectional shape of the material is made into a U-shape. This is shaped into a semi-circular arc while applying tension using a stretch bend machine, and finally the stay attachment holes are formed by piercing, etc. The process includes blank, foam, curling, re-strike, and U. It requires various processes such as bending, stretching foam, and piercing, and can manufacture high-precision fenders efficiently and inexpensively, but it still has the problem of requiring a large number of processes and a large number of man-hours. .

そこで本出願人は先に特願昭５３−１２００１９号とし
て自動二輪車用のフエンダや車両用のバツパの如き断面
Ｕ型で湾曲形状の金属薄板の成形法を提供した。Therefore, the present applicant previously provided a method for forming a curved thin metal sheet with a U-shaped cross section, such as fenders for motorcycles and bumpers for vehicles, in Japanese Patent Application No. 53-120019.

本発明者等はこれに着目し、自動二輪車用フエンダを具
体的に高精度に簡易な工程で得るべく本発明をなしたも
のである。The inventors of the present invention have focused on this, and have devised the present invention in order to specifically obtain a motorcycle fender with high precision and through a simple process.

本発明の目的は、金属薄板素材をフエンダの展開形状に
打ち抜くと同時にカール予備曲げステー取付孔を形成し
、該素材を断面形状がＵ字形状になる如く成形すると同
時に素材端末部を全周に亘りカーリングし、次に板厚方
向への圧力と曲げ力により素材略全部の表面に伸び変形
を与えつつ略円弧状に成形する如くし、シワのない高精
度の自動二輪車用フエンダを最少の工程で合理的に得る
ことができるようにした自動二輪車用フエンダの製造方
法を提供する。The purpose of the present invention is to simultaneously punch out a thin metal sheet material into the expanded shape of a fender, form a curl pre-bending stay attachment hole, form the material into a U-shaped cross section, and at the same time shape the end portion of the material around the entire circumference. The material is curled across the board, and then the entire surface of the material is stretched and deformed by applying pressure and bending force in the direction of the thickness of the material, forming it into an approximately circular arc shape.This creates wrinkle-free, high-precision motorcycle fenders with a minimum of manufacturing steps. To provide a method for manufacturing a motorcycle fender that can be reasonably obtained.

次に本発明の好適一実施例を添付図面に従つて詳述する
。Next, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

本発明は次の如き工程によつてフエンダを成形する。According to the present invention, a fender is formed by the following steps.

先ずその第１は、金属薄板をフエンダ展開形状に打ち抜
き、これと併せて同時にカール予備曲げ、ステー取付孔
も成形し、基本素材を得る。First, a metal thin plate is punched out into a fender development shape, and at the same time, preliminary curling and stay mounting holes are also formed to obtain a basic material.

次にこの基本素材を断面Ｕ字状に、即ち樋状になる如く
成形し、これと併せ同時に素材の全周の端末部をカーリ
ング成形し、全周の端末部にカール部を有する樋状素材
を得る。Next, this basic material is formed into a U-shaped cross section, that is, into a gutter shape, and at the same time, the end portions of the entire circumference of the material are curled to form a gutter-shaped material with curled portions at the end portions of the entire circumference. get.

更に該素材を板厚方向への圧力と曲げ力により素材の略
全部の表面に伸び変形を与えつつ略円弧状に成形する。Furthermore, the material is formed into a substantially circular arc shape while applying elongation deformation to substantially the entire surface of the material by applying pressure and bending force in the thickness direction.

以上の工程を詳細に説明する。The above steps will be explained in detail.

第１図は基本素材Ｗを示し、素材Ｗは両側が直線状で前
後が半円形で平面細長の小判状に金属薄板を打抜成形し
て得られ、かかる素材Ｗには打抜成形と同時にステー取
付孔Ｗ１・・・が所定の位置に所定の数穿孔される。Figure 1 shows a basic material W, which is obtained by punching and forming a thin metal plate into an oval shape with straight sides, semicircular front and back, and an elongated plane. A predetermined number of stay attachment holes W1 are bored at predetermined positions.

そして素材Ｗの好ましくは全周、少くとも両側の端末部
は、上記打抜成形と同時に第３図に示される如く中間部
Ｗ２より板厚分一段高い下向きの逆凹溝状のカーリング
予備成形段部Ｗ３，Ｗ３が予じめ成形され、フエンダ展
開形状で取付孔及び予備成形段部を備える成形基本素材
Ｗを得る。これらの形状、孔及び予備成形部は一回の抜
打成形工程で成形する。以上の素材Ｗを樋状に成形する
と同時に全周カーリング加工を行い、これを第２図乃至
第９図に示す。Preferably, the entire circumference of the material W, at least the end portions on both sides, is simultaneously formed by the above-mentioned punching and forming, as shown in FIG. The parts W3, W3 are formed in advance to obtain a molded basic material W having a fender developed shape and having attachment holes and a preformed stepped part. These shapes, holes and preforms are formed in a single stamping process. The above-mentioned material W was formed into a gutter shape and simultaneously curled all around, which is shown in FIGS. 2 to 9.

第２図は成形装置１を示し、図は右半分を断面とした半
裁断面図を示しているが、左右対称の機構を有する。FIG. 2 shows the molding apparatus 1, and although the figure shows a half-cut cross-sectional view with the right half as a cross-section, it has a symmetrical mechanism.

上型２は可動型で、これの長さ方向、図では左右方向の
中央部で幅方向の中央部に前後、即ち図の左右方向に開
放する逆Ｕ字型の溝状のＵ曲げ用ダイ３が下向きに開放
される如く設けられており、該ダイ３の成形溝３ａはフ
エンダの断面形状の外側の形状に設定されている。The upper mold 2 is a movable mold, and has an inverted U-shaped groove-shaped U-bending die that opens front and back, that is, in the left-right direction in the figure, at the center in the width direction at the center in the length direction, in the left-right direction in the figure. The molding groove 3a of the die 3 is set to have a shape outside the cross-sectional shape of the fender.

上型２の前後の左右両側にはガイド凹部２ａが縦設され
、上型２は図示しないブレス機によりで昇降動する。４
は下型本体でこれもブレス機ボルスター上にあり、本体
４は平面枠状で、これに囲まれるフローティングベース
５はダイクッションピン６・・・で゛支持され、ベース
５の上面中央部には前記ダイ３の成形溝３ａと適合する
上方に湾曲した略弧状でフエンダ内面の断面形状に適合
した成形突部７ａを備えるＵ曲げパンチ７が前後方向（
図では左右方向）に設けられている。Guide recesses 2a are vertically provided on both left and right sides of the upper mold 2, and the upper mold 2 is moved up and down by a press machine (not shown). 4
is the lower die main body, which is also located on the press machine bolster.The main body 4 has a planar frame shape, and the floating base 5 surrounded by this is supported by die cushion pins 6. A U-bending punch 7 is provided with a forming protrusion 7a that is curved upward and has a substantially arc shape that matches the forming groove 3a of the die 3 and matches the cross-sectional shape of the inner surface of the fender.
They are provided in the horizontal direction (in the figure).

下型本体４の両側部４ａ上には一対の両側部カールダイ
８，８が固設され、ダイ８の各上端部には逆Ｕ字溝状の
成形溝８ａが上面に開放される如く設けられ、該ダイ８
，８はパンチ７の両側下辺に平常は位置し、パンチ７及
びダイ３間で成形される素材Ｗの長さ方向に亘り、且つ
素材Ｗの両側に臨む如く配設されている。A pair of side curling dies 8, 8 are fixedly installed on both sides 4a of the lower mold body 4, and an inverted U-shaped molding groove 8a is provided at each upper end of the die 8 so as to be open to the upper surface. , the die 8
, 8 are normally located at the lower sides of both sides of the punch 7, and are disposed so as to extend in the length direction of the material W to be formed between the punch 7 and the die 3, and to face both sides of the material W.

一方、既述のフローテイングベース５の前記パンチ７の
前後、図では左右に前後部カールダイ９，９が向い合う
ように摺動自在に設けられ、ダイ９，９の向い合う端面
には各対向する方向、即ち夫々内向きに開放されるＵ字
状の成形溝９ａが各設けられている。そして溝９ａは素
材がＵ字型樋状に成形された場合の素材の前後部のカー
リングビード三次元形状に適合する如く設けられ、且つ
ダイ９，９の対向端部９ｂ，９ｂは素材の前後部の平面
投影形状に適合する如く平面向い合うＵ字状に形成され
ている。以上の前後部カールダイ９，９の各外方寄り部
には横断する如くピン９ｃを各設け、ピン９ｃの各両端
部にはガイドローラ１０を枢支する。一方、下型本体４
の前後寄り部の両側にはガイドプレート１１・・・を固
設し、該プレート１１・・・の上部には山部が夫々内方
向に向く如く前後で対称的な横Ｖ型のカム溝１２を各形
成し、カム溝１２は各プレート１１・・・の内面に形成
され、該カム溝１２に各ダイ９の両側に突出したローラ
１０を係合せしめる。以上において、素材Ｗを第２図及
び第３図に示される如くダイ３及びパンチ７間に投入し
、その後上型が下降し、パンチ７の突部７ａ中央部で素
材Ｗの下面中央部を支持し、ダイ３の成形溝３ａ両側の
フラットな下面３ｂ，３ｂが素材Ｗの両側の予備成形段
部Ｗ３，Ｗ３の上面に達する状態となる。On the other hand, front and rear curling dies 9, 9 are slidably provided to face each other in front and rear of the punch 7 of the floating base 5, in the figure, front and rear curling dies 9, 9 are provided so as to face each other. U-shaped molding grooves 9a are each provided which are opened inward, that is, inward. The groove 9a is provided to match the three-dimensional shape of the curling bead at the front and rear of the material when the material is formed into a U-shaped gutter shape, and the opposing ends 9b, 9b of the dies 9, 9 are provided at the front and rear of the material. They are formed in a U-shape that faces each other in plan view so as to match the planar projection shape of the part. A pin 9c is provided across each of the outer portions of the front and rear curling dies 9, 9, and a guide roller 10 is pivotally supported at each end of the pin 9c. On the other hand, the lower mold body 4
A guide plate 11 is fixed on both sides of the front and rear portions of the plate 11, and a horizontal V-shaped cam groove 12 is provided in the upper part of the plate 11, which is symmetrical in the front and rear so that the peaks thereof face inward. A cam groove 12 is formed on the inner surface of each plate 11, and rollers 10 protruding from both sides of each die 9 are engaged with the cam groove 12. In the above process, the material W is put between the die 3 and the punch 7 as shown in FIGS. 2 and 3, and then the upper die is lowered, and the center of the lower surface of the material W is touched by the center of the protrusion 7a of the punch 7. The flat lower surfaces 3b, 3b on both sides of the molding groove 3a of the die 3 reach the upper surfaces of the preformed step portions W3, W3 on both sides of the material W.

素材Ｗは上下型の長さ方向にその軸方向（長さ方向）が
沿つてセットされる。次に上型２を下動させ、これによ
りダイ３及びパンチ７の成形部３ａ，７ａで素材Ｗは断
面Ｕ字型の樋状に成形され、これを第４図及び第５図で
示し、これにより樋状の素材Ｗ４が成形される。The material W is set with its axial direction (lengthwise direction) along the length direction of the upper and lower molds. Next, the upper die 2 is moved downward, and the material W is thereby formed into a gutter shape with a U-shaped cross section by the die 3 and the forming parts 3a and 7a of the punch 7, as shown in FIGS. 4 and 5. As a result, a gutter-shaped material W4 is formed.

これと同時に成型装置１の上型本体２が下動し、これに
伴つてフローティングベース５も一体に上動し、カム溝
１２の上端に係合していたローラは該は該溝１２の各内
側に向いた斜辺１２ａに案内されて対称的に内側に摺動
案内される。これにより第２図、第４図に示される如く
素材Ｗ、或はＷ４の前後に対し離間していた前後部カー
ルダイ９，９は第６図の如く相寄る方向に案内摺動され
、斜辺１２ａ下端の横Ｖ型山部１２ｂに達し、これによ
りダイ９，９の成形溝９ａはＵ字型素材Ｗ４の前後端縁
に接し、これを内側にカーリング成形ｕ第７図に示され
る如く前後部のカール部Ｗ５が成形されることとなる。
下型本体４の更なる上昇でローラ１０はカム溝１２の下
の外方に向いた斜辺１２ｃに案内されて外方にガイドさ
れ、これによりダイ９は夫々成形終了後に外方に逃げる
ように摺動し、素材Ｗ４の両側の段部Ｗ３成形の障害と
ならないようにする。At the same time, the upper die main body 2 of the molding device 1 moves downward, and the floating base 5 also moves upward together with this, and the rollers that were engaged with the upper ends of the cam grooves 12 are moved to each side of the grooves 12. It is guided by the inwardly facing oblique side 12a and is slid symmetrically inward. As a result, the front and rear curling dies 9, 9, which were separated from the front and rear of the material W or W4 as shown in FIGS. 2 and 4, are guided and slid in the direction toward each other as shown in FIG. The forming grooves 9a of the dies 9, 9 come into contact with the front and rear edges of the U-shaped material W4, and this is curled inward as shown in FIG. A curled portion W5 is formed.
As the lower die main body 4 further rises, the roller 10 is guided outward by the oblique side 12c facing outward under the cam groove 12, so that the die 9 escapes outward after each molding is completed. It should slide so that it does not interfere with the forming of the stepped portions W3 on both sides of the material W4.

そして上記Ｕ曲げで両側の段部Ｗ３は第５図の如く下向
きに位置し、この段部Ｗ３先端部Ｗ６は対称的に内側に
折曲されていることとなり、本体２の下動の継続でフロ
ーティングベース５が下型４の両側を摺動下降しつつ成
形溝８ａが素材Ｗ４の先端部Ｗ６に接し、溝８ａにガイ
ドされつつ段部Ｗ３は内側にカーリング成形され、第９
図に示される如く素材Ｗ４の両側にカール部Ｗ７が成形
されることとなる。かくして第１０図に示される如く樋
状に成形され、且つ取付孔を備え、更には全周にカール
部を有する中間素材Ｗ８が成形されることとなる。With the U-bending described above, the stepped portions W3 on both sides are positioned downward as shown in FIG. 5, and the tips W6 of the stepped portions W3 are symmetrically bent inward. While the floating base 5 slides down on both sides of the lower die 4, the forming groove 8a comes into contact with the tip W6 of the material W4, and the step W3 is curled inward while being guided by the groove 8a.
As shown in the figure, curled portions W7 are formed on both sides of the material W4. In this way, as shown in FIG. 10, an intermediate material W8 is formed which is shaped like a gutter, has attachment holes, and further has curled portions around the entire circumference.

以上で得た中間素材Ｗ８を板厚方向に加圧しつつ曲げ成
形し、素材の略々全部の表面に伸び変形を与えつつ側面
略円弧状に成形する。この成形の具体的な一例を第１１
図以降で示し、この成形を装置と併せて説明する。The intermediate material W8 obtained above is bent while being pressurized in the thickness direction, and is formed into a substantially arcuate side surface while giving elongation deformation to substantially the entire surface of the material. A specific example of this molding is shown in the 11th section.
This molding will be explained in conjunction with the apparatus shown in the following figures.

第１１図は加圧、曲げ成形装置を示しており、前記と同
様に右半分を断面として示しているが左右対称に構成さ
れている。FIG. 11 shows a pressurizing and bending device, and although the right half is shown as a cross section as before, it is constructed symmetrically.

上型２０は昇降手段により昇降動自在で、これの下面中
央部に略々半円状の成形パンチ２１が一体に固着され、
パンチ２１の半円状下面にはフエンダの湾曲形状及び断
面形状の成形突部２１ａが設けられている。The upper die 20 is movable up and down by an elevating means, and a substantially semicircular forming punch 21 is integrally fixed to the center of the lower surface of the upper die 20.
The semicircular lower surface of the punch 21 is provided with a molded protrusion 21a having the curved shape and cross-sectional shape of a fender.

２２は下型で、前後両端にガイド孔２３，２３を備え、
孔２３に嵌装されたブッシュ２４を介してガイドポスト
２５が挿入され、ガイドポスト２５の上端は上型２０の
ガイド孔２６に嵌装されたブッシュ２７に挿入され、上
型２０はガイドポスト２５にガイドされて下型２２に対
して上下動する。22 is a lower mold, which has guide holes 23, 23 at both front and rear ends;
A guide post 25 is inserted through a bush 24 fitted into the hole 23, and the upper end of the guide post 25 is inserted into a bush 27 fitted into a guide hole 26 of the upper die 20. It moves up and down with respect to the lower die 22 while being guided by.

下型２２の上面の前後（図では左右）に装置内方及び上
方への延出部２８，２８を対称的に形成し、これ２８の
先端部にブラケット部２８ａを一体に設け、ブラケット
２８ａにストレートダイホルダ２９，２９の各外端部を
軸３０を介して軸支し、下型２２に対してストレートダ
イホルダ２９を回動自在とする。Extending portions 28, 28 extending inward and upward of the device are formed symmetrically on the front and rear (left and right in the figure) of the upper surface of the lower mold 22, and a bracket portion 28a is integrally provided at the tip of the lower mold 22. The outer ends of the straight die holders 29, 29 are supported via a shaft 30, and the straight die holder 29 is rotatable with respect to the lower die 22.

ストレートダイホルダ２９は装置中心線迄の長さを備え
、断面形状は第１４図に示される如くコ字型で、コ字状
の長溝２９ａにホルダ２９と略々同長のストレートダイ
３１を嵌挿し、これら２９，３１を固定せず、長さ方向
に摺動自在とする。ストレートダイ３１の上面を開口し
、断面略Ｕ字型の素材セット部３１ａを設け、前後で一
組をなすストレートダイ３１，３１の上部にバネ鋼で成
形した板状の制御ベルト３２を架け渡し、これの両端３
２ａ，３２ａを押板３３でダイ３１の外端部に挟着し、
ボルト等で締着する。The straight die holder 29 has a length up to the center line of the device, and has a U-shaped cross section as shown in FIG. , these 29 and 31 are not fixed, but are slidable in the length direction. The upper surface of the straight die 31 is opened, a material setting part 31a having a substantially U-shaped cross section is provided, and a plate-shaped control belt 32 formed of spring steel is stretched over the upper part of the front and rear straight dies 31, 31. , both ends of this 3
2a and 32a are sandwiched between the outer ends of the die 31 with the press plate 33,
Tighten with bolts, etc.

これによソー組のストレートダイ３１，３１をその両外
端部においてベルト３２で相互に結合されることとなる
。制御ベルト３２は素材の曲げ成形時、前記パンチ２１
に沿つたダイ３１の転動周長を決定し、且つ弾発力によ
りダイ３１を旧位に復帰させるものであり、又ダイ３１
の素材セット部３１ａは光沢のある鏡面に仕上げてある
。上型２０と下型２２との間にはカウンタプレッシャバ
ッド３４を設け、バッド３４の水平な中央部３４ａの両
端部３４ｂ，３４ｂを上方に起設するとともに、両端部
３４ｂに前記ガイドポスト２５を上下に貫通させて固定
する。As a result, the straight dies 31, 31 of the saw assembly are connected to each other by the belt 32 at both outer ends thereof. The control belt 32 is connected to the punch 21 during bending and forming of the material.
This method determines the rolling circumference of the die 31 along
The material setting section 31a has a glossy mirror finish. A counter pressure pad 34 is provided between the upper mold 20 and the lower mold 22, and both ends 34b, 34b of the horizontal central portion 34a of the pad 34 are raised upward, and the guide posts 25 are mounted on both ends 34b. Pass it through the top and bottom and fix it.

ストレートダイホルダ２９の内端部下面にはカウンタプ
レッシャシュー３５をピン３６で枢着し、該シュー３５
をバッド中央部３４ａ上面に摺動自在に取り付け、スト
レートダイホルダ２９をバッド３４に対して摺動可能と
する。このバッド３５の下方にはダイクッションピン３
７・・・を多数本並設する。以上において、ストレート
ダイ３１のセット部３１ａに既述の如く断面Ｕ字型で全
周にカール部を成形し、取付孔を成形した樋状の中間素
材Ｗ８をフリー状態で載置セットする。先ず上型２０を
降下せしめ、ガイド孔２６のブッシュ２７にガイドポス
ト２５を嵌挿させるとともに、パンチ２１の下頂部を素
材Ｗ８の上向きとなつた内面に接触させ、この状戴を第
１１図で示した。上型２０の更なる降下で素材Ｗにパン
チ２１の押圧力が作用し、押圧力はダイ３１、ストレー
トダイホルダ２９に加わり、カウンタプレッシャバッド
３４に作用し、バッド３４はダイクッションピン３７・
・・のクッション圧に抗して下動する。A counter pressure shoe 35 is pivotally attached to the lower surface of the inner end of the straight die holder 29 with a pin 36.
is slidably attached to the upper surface of the bat central portion 34a, so that the straight die holder 29 can be slid with respect to the bat 34. Below this pad 35 is a die cushion pin 3.
A large number of 7... are installed in parallel. In the above process, a curled portion having a U-shaped cross section is formed around the entire circumference of the setting portion 31a of the straight die 31 as described above, and the gutter-shaped intermediate material W8 having a mounting hole formed therein is placed and set in a free state. First, the upper mold 20 is lowered, and the guide post 25 is inserted into the bush 27 of the guide hole 26, and the lower top of the punch 21 is brought into contact with the upwardly facing inner surface of the workpiece W8, and this state is shown in FIG. Indicated. As the upper mold 20 further descends, the pressing force of the punch 21 acts on the material W, and the pressing force is applied to the die 31 and the straight die holder 29, and acts on the counter pressure pad 34, which in turn acts on the die cushion pin 37.
It moves downward against the cushion pressure of...

上型２０の降下の継続により該上型２０は下型２２に近
づき、この結果一対のストレートダイ２９，２９は軸３
０を申心として下方に開くように揺動し、この揺動はカ
ウンタプレッシャシュー３５がバッド３４上面を揺動す
ることによつてなされる。これに伴つて前記した制御ベ
ルト３２はパンチ２１の周端面２１ｂに巻き付く如く当
接し、且つ素材Ｗ８をセットしたストレートダイ３１は
パンチ２１の外周面に倣う如く転動し、ストレートダイ
ホルダ２９の回動変位量とベルト３２の長さの差に対応
してダイ３１はホルダ２９に対して摺動し、第１２図に
示す如き状態となる。ストレートダイ３１がパンチ２１
に倣いつつ転動する間に素材Ｗ８の曲げ加工がなされ、
この曲げ加工時、素材Ｗ８にはパンチ２１による曲げ力
の他にバッド３４、シュー３５、ストレートダイホルダ
２９、ストレートダイ３１を介して前記ダイクッション
ピン３７のクッション圧力が作用することとなり、この
ため素材Ｗ８には板厚方向への圧力が働き、この圧力は
多数本並設したピン３７・・・により素材Ｗ８の曲げ成
形を通して加わる。As the upper mold 20 continues to descend, the upper mold 20 approaches the lower mold 22, and as a result, the pair of straight dies 29, 29 move toward the shaft 3.
It swings so as to open downward with 0 as its center, and this swing is made by the counterpressure shoe 35 swinging on the upper surface of the pad 34. Along with this, the control belt 32 described above comes into contact with the circumferential end surface 21b of the punch 21 so as to wrap around it, and the straight die 31 with the material W8 set thereon rolls to follow the outer circumferential surface of the punch 21, causing the rotation of the straight die holder 29. The die 31 slides relative to the holder 29 in accordance with the difference between the amount of dynamic displacement and the length of the belt 32, resulting in a state as shown in FIG. 12. Straight die 31 is punch 21
While rolling while following the bending process of the material W8,
During this bending process, in addition to the bending force from the punch 21, cushion pressure from the die cushion pin 37 is applied to the material W8 via the pad 34, shoe 35, straight die holder 29, and straight die 31. Pressure in the thickness direction acts on W8, and this pressure is applied through bending of the material W8 by a large number of pins 37 arranged in parallel.

第１５図及び第１６図は上記の曲げ成形原理を簡略化し
て示し、金属材料に曲げ荷重を作用させると、材料内部
には中立軸を境界として圧縮変形部分、伸び変形部分が
発生し、伸び変形を発生させる引張力は圧縮変形部分の
圧縮変形抵抗力によつて生じる。この場合に厚さ方向へ
の圧力が作用していればこの圧縮変形抵抗力は極めて大
きくなり、又伸び変形抵抗力は小さくなるため、第１６
図に示される如く中立軸Ｎ−Ｎの位置は厚さ方向への圧
力を加えていない単純曲げの場合と比較して素材Ｗ８の
曲げ方向内側に偏位することとなり、弾性限界を越える
厚さ方向荷重によつて素材の略略全表面を伸び変形させ
て曲げ成形することができる。以上により厚さ方向圧力
を受けつつ曲げ加工される素材は略々全部が伸び変形に
よつてフエンダ形状に成形されることとなり、より少な
い材料で成形でき、得られたフエンダはシワ、デフオー
ム等が発生せず、良好な仕上面が得られ、更にはストレ
ートダイを鏡面仕上しているためフエンダの成形面には
これが転写され、光沢のある鏡面を得ることができ、爾
後バフ研摩等による仕上加工を必要としない。Figures 15 and 16 show the above-mentioned bending principle in a simplified manner. When a bending load is applied to a metal material, a compressive deformation part and an elongation deformation part occur inside the material with the neutral axis as the boundary, and The tensile force that causes the deformation is generated by the compressive deformation resistance force of the compressively deformed portion. In this case, if pressure is applied in the thickness direction, this compressive deformation resistance force will be extremely large, and the elongation deformation resistance force will be small.
As shown in the figure, the position of the neutral axis N-N is deviated inward in the bending direction of the material W8 compared to the case of simple bending where no pressure is applied in the thickness direction, and the thickness exceeds the elastic limit. By applying a directional load, substantially the entire surface of the material can be stretched and deformed to form a bend. As a result of the above, almost all of the material that is bent while being subjected to pressure in the thickness direction is formed into a fender shape by elongation deformation, so that it can be formed with less material, and the obtained fender has no wrinkles, deformation, etc. This does not occur and a good finished surface is obtained.Furthermore, since the straight die is mirror finished, this is transferred to the molding surface of the fender, resulting in a glossy mirror surface, which can then be finished by buffing etc. does not require.

以上により第１７図に示される如きフエンダを得ること
ができる。Through the above steps, a fender as shown in FIG. 17 can be obtained.

以上の樋状中間素材の加圧曲げ成形装置は上記に限られ
ず、要は板厚方向に加圧しつつ素材全面に伸び変形を与
つつ略々円弧状に成形すれば良い。The pressure bending apparatus for the trough-like intermediate material is not limited to the above, but it is sufficient to form the material into a substantially arc shape while applying pressure in the thickness direction and elongating deformation to the entire surface of the material.

以上で明らかな如く本発明によれば、金属薄板をフエン
ダ展開形状に打抜き、同時にカール予備曲げ、取付孔を
成形し、これを断面Ｕ字型の樋状に成形して同時に全周
をカーリングし、爾後板厚方向に加圧しつつ全表面に伸
び変形を与えつつ略円弧状に成形して自動二輪車のフエ
ンダを製造するようにしたため、先ず素材の打抜、同時
穿孔の工程と、樋状成形、同時の全周カーリング成形の
工程と、弧状成形の三工程でフエンダを製造することが
可能となり、従来に比しフエンダの製造工程を大幅に簡
略化することができ、製造の容易イＫコストダウン、設
備の省略を図ることができる他、得られた製品も爾後の
仕上加工を必要としない程度のものが精度良く得られ、
良好なフエンダを最少の工程で得られる等多大の利点を
有する。As is clear from the above, according to the present invention, a thin metal plate is punched out into a fender development shape, at the same time it is pre-curled, a mounting hole is formed, this is formed into a gutter shape with a U-shaped cross section, and the entire circumference is curled at the same time. After that, we decided to manufacture motorcycle fenders by applying pressure in the thickness direction while applying elongation deformation to the entire surface and forming it into a substantially circular arc shape.The first step was to punch the material, simultaneously drill holes, and form the gutter shape. It is now possible to manufacture fenders in three processes: simultaneous full circumference curling and arc forming, which greatly simplifies the fender manufacturing process compared to conventional methods, making manufacturing easier and lower costs. In addition to being able to omit downtime and equipment, the resulting product can be obtained with high precision and does not require subsequent finishing processing.
It has many advantages such as being able to obtain a good fender with a minimum number of steps.

【図面の簡単な説明】[Brief explanation of the drawing]

図面は本発明の好適一実施例を示すもので、第１図はフ
エンダ基本素材の斜視図、第２図は素材の断面Ｕ曲げ成
形及び全周カーリング成形を同時に行う装置の半裁側面
図、第３図は同要部の拡大端断面図、第４図はＵ曲げ成
形時の第２図と同様の図、第５図は第４図の状態の第３
図と同様の図、第６′図は素材前後部のカーリング成形
時の第２図と同様の図、第７図は成形素材の要部の拡大
断面図、第８図は両側カーリング成形時の第２図と同様
の図、第９図は第８図の状態の第３図と同様の図、第１
０図は得られた中間素材の斜視図、第１１図は曲げ成形
装置の半裁正面図、第１２図は成形状態の第１１図と同
様の図、第１３図は装置の一部を断面とした半裁平面図
、第１４図は第１３図の１４−１４線断面図、第１５、
第１６図は原理説明図、第１７図は得られたフエンダの
斜視図である。 尚図面中Ｗは基本素材、Ｗ１は取付孔、Ｗ４は中間素材
、Ｗ５，Ｗ７はカール部、Ｗ８は製品である。The drawings show a preferred embodiment of the present invention, and FIG. 1 is a perspective view of a basic fender material, FIG. 2 is a half-cut side view of an apparatus that simultaneously performs cross-sectional U-bending and full-circumference curling of the material, and FIG. Figure 3 is an enlarged end cross-sectional view of the same essential part, Figure 4 is a view similar to Figure 2 during U-bending, and Figure 5 is the third view in the state shown in Figure 4.
Figure 6' is a view similar to Figure 2 when curling the front and rear parts of the material, Figure 7 is an enlarged sectional view of the main part of the forming material, and Figure 8 is when curling on both sides. Figure 9 is a diagram similar to Figure 2, Figure 9 is a diagram similar to Figure 3 in the state of Figure 8;
Fig. 0 is a perspective view of the obtained intermediate material, Fig. 11 is a half-cut front view of the bending forming device, Fig. 12 is a view similar to Fig. 11 in the forming state, and Fig. 13 is a cross section of a part of the device. FIG. 14 is a cross-sectional view taken along the line 14-14 in FIG. 13, and FIG.
FIG. 16 is a diagram explaining the principle, and FIG. 17 is a perspective view of the obtained fender. In the drawings, W is a basic material, W1 is a mounting hole, W4 is an intermediate material, W5 and W7 are curled parts, and W8 is a product.

Claims (1)

【特許請求の範囲】[Claims] １ 金属薄板素材をフエンダの展開形状に打ち抜き、且
つ同時にカール予備曲げ、ステー取付孔を成形する基本
素材を成形する工程と、基本素材を断面形状がＵ字状で
樋状に成形し、且つ同時に素材の端末部全周をカーリン
グ成形して中間素材を成形する工程と、中間素材を板厚
方向への圧力と曲げ力により該素材略々全表面に伸び変
形を与えつつ略々円弧状に成形する工程とからなる自動
二輪車用フエンダの製造方法。1. A process of punching out a thin metal sheet material into the developed shape of the fender, and at the same time pre-curling and forming the basic material to form the stay attachment holes, and forming the basic material into a gutter shape with a U-shaped cross section, and at the same time. A process of forming an intermediate material by curling the entire circumference of the end portion of the material, and forming the intermediate material into a roughly circular arc shape while applying elongation deformation to almost the entire surface of the material by applying pressure and bending force in the thickness direction. A method for manufacturing a motorcycle fender comprising the steps of: