JPS61253129A - Hydraulic pressure forming - Google Patents

Abstract

PURPOSE:To prevent an unsymmetrical deformation of a product to be formed by providing a surface of a blank holder for hydraulic pressure forming facing to a die with an annular groove so as to block a movement of the part generated fold by generating the fold at an external periphery of the product reached to the groove. CONSTITUTION:A product 1 to be formed is pinch-holded between a blank holder 13 contained within a cover 2, and the pressure liquid is introduced an entrance hole 6 through a flow inlet 5 so that the product 1 is deformed along a recessed part 7 for forming. In this instance, a surface of the blank holder 13 facing to a die 4 is provided with an annular groove 14, and a fold 15 is generated on an external periphery of a flange 11 of the product 1 reached the groove 14 during forming. Thereby the product 1 is blocked for movements by means of the fold 15. Thus, an unsymmetrical deformation of the product is prevented.

Description

【発明の詳細な説明】 〈産業上の利用分野〉 本発明は、被成形品が非対称に変形するのを防止した液
圧成形方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a hydraulic molding method that prevents asymmetrical deformation of a molded product.

〈従来の技術〉 第４図によシ従来の液圧成形方法を説明すると、被成形
品１は蓋２内に収納されたしわ押え板３とダイス４との
間に挾まれ、蓋２の圧力液流入口５に圧力液を流入する
と、この圧力液はしわ押え板３に穿設された圧力液流入
孔６を通って被成形品１を押し下げ、ダイス４に形成さ
れた成形用凹部７に沿って変形される。この時、しわ押
え板３は、蓋２のバネ用孔８に圧装されたバネ９によシ
被成形品ｌに適度の圧力で押し付けられておシ、被成形
品１にしわが生じることがなく、また蓋２とダイス４の
最外周部においてシールされているので圧力液が洩れる
ことがない。また、ダイス４には空気抜き孔１０が穿設
されている。<Prior art> The conventional hydraulic forming method will be explained with reference to FIG. When the pressure fluid flows into the pressure fluid inlet 5, the pressure fluid passes through the pressure fluid inflow hole 6 formed in the wrinkle holding plate 3, pushes down the molded product 1, and presses down the molded product 1 into the molding recess 7 formed in the die 4. is deformed along. At this time, the wrinkle pressing plate 3 is pressed against the molded product 1 with a moderate pressure by the spring 9 fitted into the spring hole 8 of the lid 2, thereby preventing wrinkles from forming on the molded product 1. Moreover, since the lid 2 and the die 4 are sealed at their outermost peripheries, no pressure fluid leaks. Further, the die 4 is provided with an air vent hole 10.

〈発明が解決しようとする問題点〉 このように１被成形品１は成形途中、外周にしわ押え力
をうけているが、力を円周上均一に与えることは困難で
あシ、また、均一に与え得たとしても、被成形品変形が
ダイス４中心に対して非対称に変形してもこれを防止す
る作用は小さい。このため、被成形品１はダイス４中心
に対して非対称に変形し、７ランノ部１１が片側だけダ
イス４内に絞シ込まれることが多く（成形品１２の一例
を第５図に示す。）、水洩れを生じて成形できなくなる
。<Problems to be Solved by the Invention> As described above, the molded product 1 is subjected to wrinkle pressing force on the outer periphery during molding, but it is difficult to apply the force uniformly over the circumference. Even if the deformation can be applied uniformly, even if the molded product is deformed asymmetrically with respect to the center of the die 4, the effect of preventing this deformation is small. For this reason, the molded product 1 is deformed asymmetrically with respect to the center of the die 4, and the seven-run part 11 is often squeezed into the die 4 only on one side (an example of the molded product 12 is shown in FIG. 5). ), water leaks and molding becomes impossible.

この対策として、被成形品１の径を大きくすることが可
能であるが、材料歩留シが悪くなシ、また、張出し成形
に近くなるため板厚減小の問題を生じる。As a countermeasure to this problem, it is possible to increase the diameter of the molded product 1, but this results in poor material yield and also causes the problem of reduction in board thickness since it becomes similar to stretch molding.

本発明は、かかる従来技術の問題点を解消し、被成形品
が非対称に変形するのを防止した液圧成形方法を提供す
ることを目的とする。SUMMARY OF THE INVENTION An object of the present invention is to provide a hydroforming method that solves the problems of the prior art and prevents asymmetrical deformation of a molded product.

く問題点を解決するための手段〉 斯かる目的を達成する本発明の構成は、成形用凹部を有
するダイスと圧力液流入孔の形成されたしわ押え板との
間に被成形品を挾圧すると共に前記圧力液流入孔から圧
力液を流入して前記被成形品を前記成形用凹部に沿わせ
て変形させる液圧成形方法において、前記しわ押え板と
ダイスの対向面の少なくとも一方に円周方向に沿う溝を
設けることにより溝部に達した被成形品外周部にしわを
発生させ、このしわでその部分の被成形品が移動するの
を防止することを特徴とする。Means for Solving the Problems> The structure of the present invention to achieve the above object is to sandwich and press a molded product between a die having a molding recess and a wrinkle holding plate in which a pressure fluid inflow hole is formed. In the hydraulic forming method, the pressurized liquid flows in from the pressure liquid inflow hole to deform the molded product along the molding recess. By providing a groove along the groove, wrinkles are generated on the outer periphery of the molded product that reaches the groove, and these wrinkles prevent the molded product from moving in that area.

〈実施例〉 第１図ないし第３図によシ本発明の一実施例を説明する
と、被成形品１は蓋２内に収納されたしわ押え板１３と
ダイス４との間に挾まれ、しわ押え板１３は蓋２のバネ
用孔８に圧装されたバネ９によシ被成形品１に適度の圧
力で押し付けられている。そして、蓋２に形成された圧
力液流入口５に圧力液を流入すると、この圧力液はしわ
押え板１３に形成され前記圧力液流入口５に連通ずる圧
力液流入孔６を通って、被成形品１を押し下げ、ダイス
４に形成された成形用凹部７に沿って変形させる。そし
て、蓋２とダイス４の最外周部はおいてシールされてい
るので圧力液は洩れることがない。また、ダイス４には
空気抜き孔１０が穿設されている。そして、本実施例に
おいては、しわ押え板１３のダイス４との対向面に環状
溝１４が設けである。従って、成形中、被成形品１の７
ランフ１１外局部かしわ押え板１３の環状溝１４に達す
ると、７ランソ１１の外周部は円周方向に圧縮力をうけ
ているので環状の溝部１４でしわ１５を発生する。この
ため、第３図の矢印で示したようＫ、ダイス４内へ引込
む力Ｆに対し溝１４の壁にしわ１５が接して前記ダイス
４内に引込む力Ｆに抵抗する。このため、この部分の移
動量はなくなるか減少する。このようにして、被成形品
１が非対象に変形するのが防止される。従って、被成形
品１の径を小さくできるので、材料の歩留シが向上し、
板厚減小量も小さくなる。<Embodiment> An embodiment of the present invention will be described with reference to FIGS. 1 to 3. A molded product 1 is held between a wrinkle presser plate 13 housed in a lid 2 and a die 4, The wrinkle pressing plate 13 is pressed against the molded product 1 with an appropriate pressure by a spring 9 that is press-fitted in a spring hole 8 of the lid 2. When the pressure liquid flows into the pressure liquid inlet 5 formed in the lid 2, this pressure liquid passes through the pressure liquid inflow hole 6 formed in the wrinkle press plate 13 and communicates with the pressure liquid inlet 5, and then passes through the pressure liquid inlet 6, which is formed in the wrinkle press plate 13 and communicates with the pressure liquid inlet 5. The molded product 1 is pushed down and deformed along the molding recess 7 formed in the die 4. Since the outermost periphery of the lid 2 and the die 4 are sealed together, the pressure liquid will not leak. Further, the die 4 is provided with an air vent hole 10. In this embodiment, an annular groove 14 is provided on the surface of the wrinkle pressing plate 13 facing the die 4. Therefore, during molding, 7 of molded product 1
When the luff 11 reaches the annular groove 14 of the outer local wrinkle presser plate 13, the outer circumferential portion of the seven lances 11 is subjected to a compressive force in the circumferential direction, so that wrinkles 15 are generated in the annular groove portion 14. Therefore, as shown by the arrow in FIG. 3, the wrinkles 15 come into contact with the wall of the groove 14 and resist the force F pulling into the die 4. Therefore, the amount of movement of this portion is eliminated or reduced. In this way, the molded article 1 is prevented from deforming asymmetrically. Therefore, the diameter of the molded product 1 can be reduced, improving the material yield,
The amount of plate thickness reduction also becomes smaller.

前記環状溝１４はダイス４のしわ押え板１３との対向面
に設けてもよく、ダイス４としわ押え板１３の少なくと
も一方の面に設ければよい。また、溝１４の幅は被成形
品１の径、厚さ等で異なり、溝１４の数は１個でもよい
が複数個でもよい。また、溝１４の角部は第３図に示す
ようＫＲ部１６とするのが好ましい。また、しわ１５を
発生させる溝は環状溝１４でなく、円弧溝でもよい。The annular groove 14 may be provided on the surface of the die 4 facing the wrinkle presser plate 13, or may be provided on at least one surface of the die 4 and the wrinkle presser plate 13. Furthermore, the width of the groove 14 varies depending on the diameter, thickness, etc. of the molded product 1, and the number of grooves 14 may be one or more. Furthermore, it is preferable that the corner portions of the grooves 14 be KR portions 16 as shown in FIG. Furthermore, the grooves that generate the wrinkles 15 may be circular arc grooves instead of the annular grooves 14.

なお、以上の被成形品１移動防止は、ゴム成形等にも適
用できる。Note that the above-described prevention of movement of the molded product 1 can also be applied to rubber molding and the like.

〈発明の効果〉 以上、図面に示した実施例にもとすいて説明したように
１本発明によれば、しゎ押え板とダイスの対向面の少な
くとも一方に設けた円周方向に沿う溝部に達した被成形
品外周部にしわを発生させ、このしわでその部分の被成
形品が移動するのを防止することにょシ、被成形品が非
対称に変形するのが防止される。<Effects of the Invention> As explained above with reference to the embodiments shown in the drawings, according to the present invention, the groove portion along the circumferential direction provided on at least one of the facing surfaces of the pressing plate and the die. By generating wrinkles on the outer periphery of the molded product that has reached this point and preventing the molded product from moving in that area, asymmetrical deformation of the molded product can be prevented.

従って、小径の被成形品を使用できるので、材料の歩留
シが向上すると共に、絞シ抵抗が小さくな〕板厚変化が
小さくなる。Therefore, since it is possible to use a small-diameter molded product, the material yield is improved, the drawing resistance is reduced, and the change in plate thickness is reduced.

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

第１図は本発明の一実施例に使用する装置の断面図、第
２図は第１図中のしゎ押え板の一部分を示す拡大断面図
、第３図は第１図中の部分拡大断面図でしわを発生した
状態を示し、第４図は従来の液圧成形に使用する装置の
断面図、第５図は第４図の装置を使用した絞り成形品の
一例を示す斜視図である。 図面中、１は被成形品、４はダイス、６は圧力液流入孔
、７は成形用凹部、１３はしわ押え板、１４は環状溝、
１５はしわである。Fig. 1 is a sectional view of a device used in an embodiment of the present invention, Fig. 2 is an enlarged sectional view showing a part of the presser plate in Fig. 1, and Fig. 3 is an enlarged partial view of Fig. 1. A cross-sectional view shows a state in which wrinkles have been generated, FIG. 4 is a cross-sectional view of a device used for conventional hydraulic forming, and FIG. 5 is a perspective view showing an example of a drawn product using the device shown in FIG. be. In the drawing, 1 is a molded product, 4 is a die, 6 is a pressure liquid inflow hole, 7 is a molding recess, 13 is a wrinkle pressing plate, 14 is an annular groove,
15 is a wrinkle.

Claims (1)

【特許請求の範囲】[Claims] 成形用凹部を有するダイスと圧力液流入孔の形成された
しわ押え板との間に被成形品を挾圧すると共に前記圧力
液流入孔から圧力液を流入して前記被成形品を前記成形
用凹部に沿わせて変形させる液圧成形方法において、前
記しわ押え板とダイスの対向面の少なくとも一方に円周
方向に沿う溝を設けることにより溝部に達した被成形品
外周部にしわを発生させ、このしわでその部分の被成形
品が移動するのを防止することを特徴とする液圧成形方
法。A molded product is clamped between a die having a molding recess and a wrinkle holding plate in which a pressure fluid inflow hole is formed, and a pressure fluid is introduced from the pressure fluid inflow hole to move the molded product into the molding recess. In a hydropressure forming method in which the molded product is deformed along the groove, a groove is provided along the circumferential direction on at least one of the opposing surfaces of the wrinkle presser plate and the die, so that wrinkles are generated on the outer periphery of the molded product that reaches the groove, A hydroforming method characterized in that the wrinkles prevent the part to be molded from moving.