JP5616877B2 - Bending method of aluminum alloy hollow extruded section, aluminum alloy hollow extruded section and automobile battery frame manufacturing method using this method, automobile battery frame and seat frame structure manufacturing method, and seat frame structure - Google Patents
Bending method of aluminum alloy hollow extruded section, aluminum alloy hollow extruded section and automobile battery frame manufacturing method using this method, automobile battery frame and seat frame structure manufacturing method, and seat frame structure Download PDFInfo
- Publication number
- JP5616877B2 JP5616877B2 JP2011255425A JP2011255425A JP5616877B2 JP 5616877 B2 JP5616877 B2 JP 5616877B2 JP 2011255425 A JP2011255425 A JP 2011255425A JP 2011255425 A JP2011255425 A JP 2011255425A JP 5616877 B2 JP5616877 B2 JP 5616877B2
- Authority
- JP
- Japan
- Prior art keywords
- bending
- hollow extruded
- shape
- aluminum alloy
- alloy hollow
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Bending Of Plates, Rods, And Pipes (AREA)
Description
本発明は、アルミニウム合金製中空押出形材の曲げ加工方法並びにこの方法を用いたアルミニウム合金製中空押出形材に関し、特に小さな曲げ半径で曲げ加工する場合に有効なアルミニウム合金製中空押出形材の曲げ加工方法並びにアルミニウム合金製中空押出形材に関する。さらに本発明は、前記中空押出形材の曲げ加工方法を用いた自動車用バッテリーフレーム製造方法と自動車用バッテリーフレーム及び座席のフレーム構造体製造方法と座席のフレーム構造体に関する。 The present invention relates to a method for bending an aluminum alloy hollow extruded shape and an aluminum alloy hollow extruded shape using the method, and more particularly to an aluminum alloy hollow extruded shape effective when bending with a small bending radius. The present invention relates to a bending method and an aluminum alloy hollow extruded shape. Furthermore, the present invention relates to an automobile battery frame manufacturing method, an automotive battery frame, a seat frame structure manufacturing method, and a seat frame structure using the hollow extruded profile bending method.
中空押出形材で構成された枠状フレームの斜視図を図9に示す。構造用部品では、部品剛性あるいは強度を確保するために、外周部に枠状の閉断面フレームが配置されるものが多い。近年、特に自動車では車体軽量化への要望が強くなり、このような構造用部品に対して、アルミニウム合金の適用が望まれるようになってきている。特に、アルミニウム合金製中空押出形材(以下、単に「中空押出形材」とも称す)は、鋼板やアルミニウム合金板材に比べて比強度が高く、このようなフレームへの適用が期待されている。 FIG. 9 shows a perspective view of a frame-like frame made of a hollow extruded shape member. In many structural parts, a frame-like closed cross-section frame is arranged on the outer peripheral portion in order to ensure the rigidity or strength of the part. In recent years, there has been a strong demand for reducing the weight of automobile bodies, especially in automobiles, and the application of aluminum alloys to such structural parts has been desired. In particular, aluminum alloy hollow extruded profiles (hereinafter also simply referred to as “hollow extruded profiles”) have higher specific strength than steel plates and aluminum alloy sheets, and are expected to be applied to such frames.
中空押出形材は断面自由度が高く、これを比較的自由に設計できることで、断面の肉厚配分や構造最適化による軽量化が期待できるという利点はあるが、長手方向には一様で、かつ直線形状という問題がある。このため、枠状フレームを構成する場合には、中空押出形材を曲げ加工する{図9(a)参照}か、複数の直材としての中空押出形材を溶接などで接合して{図9(b)参照}製作する必要がある。このような構造用部品(枠状フレーム)は、他部品との干渉回避の観点から、枠状フレーム内外の形状制約が厳しいものが多い。このため、中空押出形材を曲げ加工する場合には、比較的小さい曲げ半径での曲げ加工が要求されることが多く、曲げ加工時の破断や座屈しわの回避が課題になっている。 The hollow extruded profile has a high degree of freedom in cross section, and it can be designed relatively freely, so there is an advantage that weight reduction can be expected by thickness distribution of the cross section and structural optimization, but it is uniform in the longitudinal direction, There is also a problem of linear shape. For this reason, when forming a frame-like frame, the hollow extruded profile is bent {see FIG. 9 (a)}, or a plurality of straight extruded profiles are joined by welding or the like {FIG. 9 (b)} needs to be manufactured. In many cases, such structural parts (frame-shaped frames) have severe shape constraints inside and outside the frame-shaped frame from the viewpoint of avoiding interference with other parts. For this reason, when a hollow extruded profile is bent, bending with a relatively small bending radius is often required, and avoiding breakage and buckling during bending is a problem.
通常、複数の直材を溶接して枠状フレームを製作する場合、これらの直材同士をほぼ直角に接合し、製作することは可能である。しかし、溶接時の熱変形により、形状精度にバラツキが生じやすいこと、また、素材によっては溶接時に熱影響で強度が低下してしまうという問題がある。また、曲げ加工費に比べて溶接費は高く、コストアップも問題になる。また、ボルトなどの締結手段による機械的接合も考えられるが、全周溶接あるいは塑性加工に比べると、点接合になることによる接合部の強度低下が問題になる。以上の点を総合的に考えると、小さい曲げ半径の曲げ加工品で枠状フレームを構成していることが望まれる。 Usually, when a frame-shaped frame is manufactured by welding a plurality of direct materials, it is possible to manufacture these direct materials by joining them at a substantially right angle. However, there is a problem that variations in shape accuracy are likely to occur due to thermal deformation during welding, and depending on the material, the strength is reduced due to thermal effects during welding. Further, the welding cost is higher than the bending cost, and the cost increase becomes a problem. In addition, mechanical joining by means of fastening means such as bolts is conceivable. However, compared with all-around welding or plastic working, there is a problem that the strength of the joint is lowered due to point joining. Considering the above points comprehensively, it is desired that the frame-like frame is constituted by a bent product having a small bending radius.
上述した中空押出形材の曲げ加工には、ドローベンダーあるいはプレスベンダーが用いられること多い。これらの加工では、曲げ内側壁の座屈しわや断面変形を抑制するために、一般に芯金と呼ばれる工具を中空押出形材の内部に挿入し、断面をある程度保持しながら曲げ加工される。しかし、特に小さい曲げ半径での曲げ加工では、曲げ外側壁での破断が生じやすくなるという問題があった。また、このような芯金を用いない場合には、断面変形が顕著になり、他部品との接合のために必要な面精度、あるいは外観性状が得られないという問題が生じる。 A draw bender or a press bender is often used for the bending process of the hollow extruded section described above. In these processes, in order to suppress buckling wrinkles and cross-sectional deformation of the bending inner wall, a tool generally called a cored bar is inserted into the hollow extruded profile, and bending is performed while maintaining the cross section to some extent. However, there is a problem that the bending outer wall tends to be broken particularly in bending with a small bending radius. In addition, when such a mandrel is not used, cross-sectional deformation becomes remarkable, and there arises a problem that the surface accuracy or appearance properties necessary for joining with other parts cannot be obtained.
アルミニウム合金製中空押出形材は、従来から用いられている鋼管などに比べてさらに伸びが小さく、破断が生じやすい。特に、素材強度が高くなるほど、伸びも小さくなる傾向にあり、高強度が要求される部品ほど加工不良が発生しやすく、成形可能な製品形状が制限されることが大きな問題であった。このような中空押出形材の曲げ加工時の破断や断面変形抑制のために、以下のような提案がなされている。 The aluminum alloy hollow extruded section has a smaller elongation than a conventionally used steel pipe and is likely to break. In particular, as the strength of the material increases, the elongation tends to decrease. As a part requiring high strength, processing defects are more likely to occur, and the shape of a product that can be molded is limited. In order to suppress breakage and cross-sectional deformation during bending of such a hollow extruded profile, the following proposals have been made.
例えば、金属パイプの曲げ加工時の破断やしわの双方の抑制のために、高周波加熱などを用いた温間成形により、素材の伸びを向上させることで破断やしわを抑制する手法が開示されている(特許文献1参照)。しかし、このような温間領域での加工では、破断回避のための加工速度低下や加熱に起因するコストアップ、素材によっては温度上昇による材質変化、熱変形による形状精度悪化も問題になる。 For example, in order to suppress both breakage and wrinkles during bending of metal pipes, a technique for suppressing breakage and wrinkles by improving the elongation of the material by warm forming using high-frequency heating or the like has been disclosed. (See Patent Document 1). However, in such processing in the warm region, there are problems in that the processing speed is reduced to avoid breakage, the cost is increased due to heating, the material changes due to temperature rise, and the shape accuracy deteriorates due to thermal deformation depending on the material.
したがって、新たに発生する上記各種の問題点を解消する技術として、中空押出形材を冷間加工により、小さい曲げ半径で精度よく曲げ加工する手法が最も望まれる。このために、中空押出形材の曲げ内側壁を断面内側に凹ませながら曲げ加工することで、小さい曲げ半径での曲げ加工破断を防止する案がいくつか提案されている(特許文献2〜6参照)。これら特許文献2〜6に開示された技術の特徴は,曲げ内側壁を断面内側に凹ませることで、断面高さを局所的に減少あるいは曲げ中立軸の曲げ外側方向への移動により、曲げ外側壁に生じるひずみ量を低減するものである。 Therefore, as a technique for solving the various problems newly generated, a technique of bending a hollow extruded shape with high accuracy with a small bending radius by cold working is most desired. For this reason, several proposals have been proposed to prevent bending breakage at a small bending radius by bending while bending the inner wall of the hollow extruded shape member into the cross section inside (Patent Documents 2 to 6). reference). The features of the techniques disclosed in these Patent Documents 2 to 6 are that the inner wall of the bend is recessed inward of the cross section, and the height of the cross section is locally reduced or the bend neutral axis is moved outward in the bend direction. This is to reduce the amount of strain generated on the wall.
特に特許文献6の技術では、中空押出形材の側面壁に予め凹部を設けた後に曲げ加工することで、曲げ内側壁を積極的に断面内側に移動させて破断を防止する方法も提案されている(特許文献6参照)。 In particular, the technique of Patent Document 6 proposes a method of preventing breakage by positively moving the bent inner wall to the inner side of the cross section by bending the side wall of the hollow extruded shape member in advance after bending. (See Patent Document 6).
さらに、中空押出形材の曲げ加工の後、中空押出形材内部から内圧を加えるハイドロフォーム成形を追加することで、変断面加工と形状精度確保の両立を図る技術も開示されている(特許文献7参照)。 Furthermore, a technique is also disclosed for achieving both the cross-section processing and ensuring the shape accuracy by adding hydroform molding that applies internal pressure from the inside of the hollow extruded profile after bending the hollow extruded profile (Patent Document). 7).
しかしながら、上記特許文献2〜7に開示された技術にも、以下のような問題点が存在する。 However, the techniques disclosed in Patent Documents 2 to 7 have the following problems.
上記特許文献2〜6に開示された技術では、曲げ内側壁が断面内側に大きく凹むが、この際、金型による拘束を受けないために凹部形状が出来なりになり、この部位の形状精度を保証し難いという問題点がある。また、特許文献3のように、曲げ内側壁の変形に起因して、側面壁が断面外側に凸変形する場合には、他部品との干渉や接合も問題になることが多い。 In the techniques disclosed in Patent Documents 2 to 6, the bent inner side wall is greatly recessed inside the cross section, but at this time, since it is not restrained by the mold, a concave shape is formed, and the shape accuracy of this part is improved. There is a problem that it is difficult to guarantee. In addition, when the side wall is convexly deformed to the outside of the cross section due to the deformation of the inner wall of the bend as in Patent Document 3, interference with other parts and joining are often problematic.
上記特許文献6に開示された技術では、側面壁に断面内側への凹部を設けていることで、断面外側への凸変形は抑制できるが、曲げ内側壁は座屈によって、断面内側に大きく凹み変形するため、曲げ内側壁の精度確保を保証し難いという問題点は上記特許文献2〜5と共通である。そして、このように曲げ内側壁が大きく凹む場合、曲げ外側壁の変形も、長手方向の狭い領域に集中することになる。これに伴って、特許文献3の図5に見られるように曲げ外側壁も局所的に断面内側への凹部が生じやすくなり、曲げ内側および外側壁の形状精度を確保しにくいという問題がある。 In the technique disclosed in Patent Document 6 described above, convex deformation to the outside of the cross section can be suppressed by providing the side wall with a concave portion on the inside of the cross section, but the bent inner wall is greatly recessed on the inside of the cross section by buckling. The problem that it is difficult to ensure the accuracy of the inner wall of the bending due to deformation is the same as in Patent Documents 2 to 5. And when a bending inner side wall is dented greatly in this way, a deformation | transformation of a bending outer side wall will also concentrate on the narrow area | region of a longitudinal direction. Along with this, as shown in FIG. 5 of Patent Document 3, the bent outer wall also tends to be locally recessed in the cross section, and there is a problem that it is difficult to ensure the shape accuracy of the bent inner and outer walls.
上記特許文献7に開示された技術は、形材内部から液圧を加えるために、端部をクランプする必要があることで素材歩留まりが悪くなったり、液圧成形適用による加工時間の長時間化などによるコストアップが問題になる。 The technique disclosed in Patent Document 7 described above requires that the end be clamped in order to apply hydraulic pressure from the inside of the shape member, resulting in poor material yield or increased processing time due to application of hydraulic forming. Cost increases due to such problems.
本発明の目的は、冷間加工により比較的小さい曲げ半径で曲げ加工可能であり、曲げ内側壁と曲げ外側壁の面精度を確保しやすいアルミニウム合金製中空押出形材の曲げ加工方法並びにこの曲げ加工方法により曲げ加工されたアルミニウム合金製中空押出形材を提供することにある。さらに、前記中空押出形材の曲げ加工方法を用いた自動車用バッテリーフレーム製造方法と自動車用バッテリーフレーム及び座席のフレーム構造体製造方法と座席のフレーム構造体を提供することも目的とする。 An object of the present invention is a method of bending an aluminum alloy hollow extruded shape which can be bent with a relatively small bending radius by cold working and can easily ensure the surface accuracy of the inner wall and the outer wall of the bend, and the bending. An object of the present invention is to provide an aluminum alloy hollow extruded shape bent by a processing method. It is another object of the present invention to provide an automotive battery frame manufacturing method, an automotive battery frame and a seat frame structure manufacturing method, and a seat frame structure using the hollow extruded shape bending method.
この目的を達成するために、本発明の請求項1に記載の発明は、
アルミニウム合金製中空押出形材の曲げ加工方法であって、
この中空押出形材に曲げ加工を施す場合の前記中空押出形材の曲げ内側半径(r)方向に略平行な側面壁の少なくとも前記曲げ加工を施す領域に、前記中空押出形材の断面内側に凹み、かつ、前記中空押出形材の長手方向に伸びる所定の凹溝を設ける第1の工程と、
前記第1の工程後に、前記内側半径(r)の中心P1と前記曲げ加工を施す場合の曲げ角度(θ)の中央(θ/2)の位置を結ぶ直線上にあり、かつ、前記曲げ加工が施される領域から見て前記中心P1より遠い所定の位置に設定された点を回転中心P2とする、前記中空押出形材の曲げ外側壁に近接して設けられた移動金型を前記回転中心P2に対して回転させながら前記中空押出形材の曲げ加工を行う第2の工程と、
を有したことを特徴とするアルミニウム合金製中空押出形材の曲げ加工方法である。
In order to achieve this object, the invention according to claim 1 of the present invention provides:
A bending method of an aluminum alloy hollow extruded section,
In the case of bending the hollow extruded profile, at least the region of the side wall that is substantially parallel to the bending inner radius (r) direction of the hollow extruded profile is formed on the inner side of the cross section of the hollow extruded profile. A first step of forming a recess and a predetermined recess extending in the longitudinal direction of the hollow extruded profile;
After the first step, there is on a straight line connecting the position of the center (θ / 2) Bending angle (theta) when subjected to the bending work with the center P 1 of the inner radius (r), and the bending processing the rotation center P 2 point set at a predetermined position distant from the center P 1 as seen from the region to be applied, the movable die provided near the bending outer wall of the cylindrical workpiece a second step of the performing bending of the cylindrical workpiece while rotating relative to the rotation center P 2,
This is a method of bending an aluminum alloy hollow extruded section characterized by comprising:
請求項2に記載の発明は、請求項1に記載の発明において、
前記所定の凹溝の前記中空押出形材の長手方向の長さDは、曲げ金型を用いて前記中空押出形材を曲げる場合の側面壁上の曲げ開始点から下記式(1)で規定した長さを満足するようにしたことを特徴とする。
B:側面壁あるいは中リブにより支持される曲げ内側壁の幅
The invention according to claim 2 is the invention according to claim 1,
The length D in the longitudinal direction of the hollow extruded profile of the predetermined groove is defined by the following formula (1) from the bending start point on the side wall when the hollow extruded profile is bent using a bending die. It is characterized by satisfying the length.
請求項3に記載の発明は、請求項1または2に記載の発明において、前記中空押出形材の断面形状は略矩形であり、この断面の角には半径3mm以上の面取りが施されていることを特徴とする。 The invention according to claim 3 is the invention according to claim 1 or 2 , wherein the hollow extruded profile has a substantially rectangular cross-sectional shape, and a corner of the cross-section is chamfered with a radius of 3 mm or more. It is characterized by that.
請求項4に記載の発明は、請求項1乃至3のいずれか1項に記載の発明において、前記中空押出形材は、少なくとも第2の工程の曲げ加工が行われる前に材料到達温度が200℃以上、かつ、20sec以下(ゼロは含まない)の熱処理が施された6000系または7000系アルミニウム合金であることを特徴とする。 According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the hollow extruded profile has a material temperature of 200 before at least the second step of bending. It is characterized by being a 6000 series or 7000 series aluminum alloy that has been subjected to a heat treatment at a temperature of 0 ° C. or more and 20 seconds or less (excluding zero).
請求項5に記載の発明は、請求項1乃至4のいずれか1項に記載のアルミニウム合金製中空押出形材の曲げ加工方法により曲げ加工されたアルミニウム合金製中空押出形材である。 The invention according to claim 5 is an aluminum alloy hollow extruded shape that is bent by the method of bending an aluminum alloy hollow extruded shape according to any one of claims 1 to 4 .
請求項6に記載の発明は、請求項1乃至4のいずれか1項に記載のアルミニウム合金製中空押出形材の曲げ加工方法によりL字形、コ字形あるいはロ字形に曲げ加工したアルミニウム合金製中空押出形材を自動車用バッテリーフレームの一部として用いることを特徴とする自動車用バッテリーフレーム製造方法である。 The invention described in claim 6 is an aluminum alloy hollow that is bent into an L-shape, a U-shape or a B-shape by the method of bending an aluminum alloy hollow extruded shape according to any one of claims 1 to 4. An automotive battery frame manufacturing method characterized by using an extruded profile as a part of an automotive battery frame.
請求項7に記載の発明は、請求項1乃至4のいずれか1項に記載のアルミニウム合金製中空押出形材の曲げ加工方法によりL字形、コ字形あるいはロ字形に曲げ加工したアルミニウム合金製中空押出形材を一部に用いてなることを特徴とする自動車用バッテリーフレームである。 The invention described in claim 7 is an aluminum alloy hollow that is bent into an L shape, a U shape, or a B shape by the method of bending an aluminum alloy hollow extruded shape according to any one of claims 1 to 4. An automotive battery frame characterized in that an extruded profile is partially used.
請求項8に記載の発明は、請求項1乃至4のいずれか1項に記載のアルミニウム合金製中空押出形材の曲げ加工方法によりL字形、コ字形あるいはロ字形に曲げ加工したアルミニウム合金製中空押出形材を座席のフレーム構造体の一部として用いることを特徴とする座席のフレーム構造体製造方法である。 The invention described in claim 8 is an aluminum alloy hollow which is bent into an L shape, a U shape or a B shape by the method of bending an aluminum alloy hollow extruded shape according to any one of claims 1 to 4. A method for manufacturing a frame structure for a seat, wherein the extruded profile is used as a part of the frame structure for the seat.
請求項9に記載の発明は、請求項1乃至4のいずれか1項に記載のアルミニウム合金製中空押出形材の曲げ加工方法によりL字形、コ字形あるいはロ字形に曲げ加工したアルミニウム合金製中空押出形材を一部に用いてなることを特徴とする座席のフレーム構造体である。 The invention described in claim 9 is an aluminum alloy hollow that is bent into an L-shape, a U-shape or a B-shape by the method of bending an aluminum alloy hollow extruded shape according to any one of claims 1 to 4. A seat frame structure characterized by using an extruded profile partly.
以上のように、本発明は、
アルミニウム合金製中空押出形材の曲げ加工方法であって、
この中空押出形材に曲げ加工を施す場合の前記中空押出形材の曲げ内側半径(r)方向に略平行な側面壁の少なくとも前記曲げ加工を施す領域に、前記中空押出形材の断面内側に凹み、かつ、前記中空押出形材の長手方向に伸びる所定の凹溝を設ける第1の工程と、
前記第1の工程後に、前記内側半径(r)の中心P1と前記曲げ加工を施す場合の曲げ角度(θ)の中央(θ/2)の位置を結ぶ直線上にあり、かつ、前記曲げ加工が施される領域から見て前記中心P1より遠い所定の位置に設定された点を回転中心P2とする、前記中空押出形材の曲げ外側壁に近接して設けられた移動金型を前記回転中心P2に対して回転させながら前記中空押出形材の曲げ加工を行う第2の工程と、を有しているため、
冷間加工により比較的小さい曲げ半径で曲げ加工可能であり、曲げ内側壁と曲げ外側壁の面精度を確保しやすいアルミニウム合金製中空押出形材の曲げ加工方法並びにこの曲げ加工方法により曲げ加工されたアルミニウム合金製中空押出形材を提供することができる。さらに、前記中空押出形材の曲げ加工方法を用いた自動車用バッテリーフレーム製造方法と自動車用バッテリーフレーム及び座席のフレーム構造体製造方法と座席のフレーム構造体を提供することもできる。
As described above, the present invention
A bending method of an aluminum alloy hollow extruded section,
In the case of bending the hollow extruded profile, at least the region of the side wall that is substantially parallel to the bending inner radius (r) direction of the hollow extruded profile is formed on the inner side of the cross section of the hollow extruded profile. A first step of forming a recess and a predetermined recess extending in the longitudinal direction of the hollow extruded profile;
After the first step, there is on a straight line connecting the position of the center (θ / 2) Bending angle (theta) when subjected to the bending work with the center P 1 of the inner radius (r), and the bending processing the rotation center P 2 point set at a predetermined position distant from the center P 1 as seen from the region to be applied, the movable die provided near the bending outer wall of the cylindrical workpiece since the has a second step for bending the cylindrical workpiece while rotating relative to the rotation center P 2,
It can be bent with a relatively small bending radius by cold working, and it can be bent with this bending method, as well as a bending method of an aluminum alloy hollow extruded profile that is easy to ensure the surface accuracy of the inner wall and the outer wall. A hollow extruded shape made of an aluminum alloy can be provided. Furthermore, an automobile battery frame manufacturing method, an automotive battery frame and a seat frame structure manufacturing method, and a seat frame structure using the hollow extruded profile bending method can be provided.
以下、具体的に図面を参照しながら、本発明に係るアルミニウム合金製中空押出形材の曲げ加工方法について説明する。 Hereinafter, a method for bending an aluminum alloy hollow extruded section according to the present invention will be described with reference to the drawings.
(実施形態)
図1は本発明の一実施形態のアルミニウム合金製中空押出形材の曲げ加工方法を説明するための模式断面図であり、(a)は中空押出形材を曲げ金型にセットした状態の正面断面図、(b)は曲げ加工前に中空押出形材の側面壁に凹溝を設ける第1の工程を示す側面断面図、(c)は中空押出形材に対して曲げ加工を施す第2の工程を示す正面断面図である。
(Embodiment)
FIG. 1 is a schematic cross-sectional view for explaining a method of bending an aluminum alloy hollow extruded profile according to an embodiment of the present invention. FIG. 1 (a) is a front view showing a state where the hollow extruded profile is set in a bending mold. Sectional drawing, (b) is a side sectional view showing a first step of providing a concave groove in the side wall of the hollow extruded profile before bending, and (c) is a second diagram for bending the hollow extruded profile. It is front sectional drawing which shows this process.
図1において、1は断面が例えばロ字形のアルミニウム合金製中空押出形材、1aは曲げ外側壁、1bは曲げ内側壁、1cは左側面壁、1dは右側面壁、2は所定の凹溝3を形成するための押込み金型、4は曲げ金型、5は背面抑え金型、6は移動金型である。 In FIG. 1, reference numeral 1 denotes a hollow extruded shape made of an aluminum alloy whose cross section is, for example, a square shape, 1 a is a bent outer wall, 1 b is a bent inner wall, 1 c is a left side wall, 1 d is a right side wall, and 2 is a predetermined groove 3. A pressing die for forming, 4 is a bending die, 5 is a back holding die, and 6 is a moving die.
図1(a)は、中心P1から曲率半径rの曲面が設けられた曲げ金型4に中空押出形材1をセットした状態を示す。 Figure 1 (a) shows a state curved surface equipped with a bending molds 4 cylindrical workpiece 1 provided the radius of curvature r from the center P 1.
図1(b)は、図1(a)のようにセットされた中空押出形材1(曲げ外側壁1aと曲げ内側壁1bの幅:B、左側面壁1cと右側面壁1dの高さ:H)の曲げ半径(r)方向に略平行な左側面壁1cと右側面壁1dにそれぞれ押込み金型2を用いて、凹溝3が直線Xに接する曲げ開始点から長さD{図1(a)参照}となるようにプレス加工により設ける工程{第1の工程}を示す。この凹溝3は、後記図1(c)に示す曲げ加工を施す領域の全長に対応するように、かつ、左側面壁1cと右側面壁1dの高さ方向中心に設けられている。本実施形態のように、凹溝3を左側面壁1cと右側面壁1dの高さ方向中心に必ずしも設ける必要はないが、より対称に近い変形形状を得るためには、左側面壁1cと右側面壁1dの高さ方向中心に設けることが好ましい。なお、上記第1工程は、左側面壁1cと右側面壁1dのそれぞれにおいて、中空押出形材1のロ字形の断面内側への凹み変形を容易に起すために設けるものであり、必要に応じて形状と深さなどは便宜選択される。 FIG. 1 (b) shows a hollow extruded profile 1 set as shown in FIG. 1 (a) (width of bent outer wall 1a and bent inner wall 1b: B, height of left side wall 1c and right side wall 1d: H ) Of the left side wall 1c and the right side wall 1d substantially parallel to the bending radius (r) direction, respectively, by using the pressing mold 2 respectively, the length D from the bending start point where the concave groove 3 is in contact with the straight line X {FIG. 1 (a) The step {first step} provided by press working so as to be referred to is shown. The concave groove 3 is provided at the center in the height direction of the left side wall 1c and the right side wall 1d so as to correspond to the entire length of the region to be bent as shown in FIG. The concave groove 3 is not necessarily provided at the center in the height direction of the left side wall 1c and the right side wall 1d as in the present embodiment, but in order to obtain a deformed shape that is more symmetrical, the left side wall 1c and the right side wall 1d Is preferably provided at the center in the height direction. The first step is provided in order to easily cause dent deformation of the hollow extruded profile 1 to the inside of the square-shaped cross section in each of the left side wall 1c and the right side wall 1d, and the shape is formed as necessary. The depth and the like are selected for convenience.
図1(c)は、左側面壁1cと右側面壁1dのそれぞれに凹溝3が設けられた中空押出形材1を曲げ金型4と背面抑え金型で挟んだ状態で、中空押出形材1の曲げ外側壁1aに近接して設けられた移動金型6を回転中心P2を中心にして矢印で示す曲げ加工方向に回転させながら中空押出形材1を例えば曲げ角度θ=90°となるように曲げ加工を行う工程(第2の工程)を示す。上記回転中心P2は、中心P1と中空押出形材1の曲げ角度(θ=90°)の中央(θ/2=45°)の位置を結ぶ直線上にあり、かつ、中空押出形材1の曲げ加工が施される領域側から見て中心P1より遠い位置に設定された中心である。 FIG. 1 (c) shows a hollow extruded profile 1 in a state where a hollow extruded profile 1 in which a concave groove 3 is provided in each of a left side wall 1c and a right side wall 1d is sandwiched between a bending mold 4 and a back surface holding mold. a hollow extruded shape member 1 for example bending angle theta = 90 ° while rotating the movable die 6 provided near the outer side wall 1a in the bending direction indicated by the arrows around the rotational center P 2 bending A step of performing bending processing (second step) is shown. The rotation center P 2 is on a straight line connecting the center P 1 and the center (θ / 2 = 45 °) of the bending angle (θ = 90 °) of the hollow extruded shape 1 and is a hollow extruded shape. 1 of bending is the center which is set at a position farther from the center P 1 as viewed from the region side to be subjected.
上述したような第1工程と第2の工程を有しているため、冷間加工により比較的小さい曲げ半径で曲げ加工可能であり、曲げ外側壁の面精度を確保しやすい{曲げ外側壁1aの“破断”を回避できる。}アルミニウム合金製中空押出形材の曲げ加工方法並びにこの曲げ加工方法により曲げ加工されたアルミニウム合金製中空押出形材を提供することができる。さらに、前記中空押出形材の曲げ加工方法を用いた自動車用バッテリーフレーム製造方法と自動車用バッテリーフレーム及び座席のフレーム構造体製造方法と座席のフレーム構造体を提供することもできる。 Since the first process and the second process as described above are included, it is possible to perform bending with a relatively small bending radius by cold working, and it is easy to ensure the surface accuracy of the bending outer wall {bending outer wall 1a Can be avoided. } A method for bending an aluminum alloy hollow extruded shape and an aluminum alloy hollow extruded shape bent by this bending method can be provided. Furthermore, an automobile battery frame manufacturing method, an automotive battery frame and a seat frame structure manufacturing method, and a seat frame structure using the hollow extruded profile bending method can be provided.
図2(a)は、図1に示す本発明の曲げ加工方法を施した場合の中空押出形材1の左側面壁1cの状態を説明するための模式説明図であり、図2(b)は同左側面壁1cの拡大模式説明図である。上述したように、移動金型6を回転中心P2を中心にして回転移動させることにより、所定の凹溝3がそれぞれ設けられた左側面壁1cと右側面壁1dのそれぞれの高さHが縮小するような変形が促進される(図2参照)。また、この曲げ加工の際には、曲げ内側壁1bが曲げ金型4に押し付けられるように変形するため、曲げ内側壁1bにしわなどの凹凸変形が生じにくく、曲げ内側壁の面精度を確保しやすい。また、本発明に係る曲げ加工方法は、前述の特許文献2〜6に記載の技術に比べると、曲げ外側壁の変形領域を広くできることで、ひずみの集中を抑制、すなわち、ひずみ量がより小さく、破断が生じにくい。そしてひずみ量が小さく、かつ、工具による拘束も作用することで曲げ外側壁の精度も確保しやすい点に特徴がある。 FIG. 2A is a schematic explanatory view for explaining the state of the left side wall 1c of the hollow extruded profile 1 when the bending method of the present invention shown in FIG. 1 is applied, and FIG. It is an expansion schematic explanatory drawing of the left side wall 1c. As described above, by rotating movement around the rotational center P 2 a movable die 6, the respective heights H of the left wall 1c and the right wall 1d of predetermined grooves 3 are each provided is reduced Such deformation is promoted (see FIG. 2). Further, since the bending inner wall 1b is deformed so as to be pressed against the bending mold 4 at the time of the bending process, the bending inner wall 1b is not easily deformed by unevenness such as wrinkles, and the surface accuracy of the bending inner wall is ensured. It's easy to do. In addition, the bending method according to the present invention can suppress the concentration of strain, that is, the strain amount is smaller by making the deformation region of the bending outer wall wider than the techniques described in Patent Documents 2 to 6 described above. It is difficult to break. And the amount of distortion is small, and it is characterized in that it is easy to ensure the accuracy of the outer wall of the bending by acting with a constraint by a tool.
上記第1の工程においては、中空押出形材1の曲げ半径方向に略平行な左側面壁1cと右側面壁1dの少なくとも曲げ加工を施す領域に、中空押出形材1の断面内側に凹み、かつ、中空押出形材1の長手方向に伸びる所定の凹溝3が設けられているため、芯金を用いなくても、曲げ加工を施す領域以外の変形が生じにくくなり、曲げ外側壁1aの面精度等の形状精度が確保しやすい{すなわち、曲げ外側壁1aの“破断”を回避できる}という利点がある。これにより、曲げ加工時の芯金の挿入不良などの問題も生じにくくなるという利点がある。また、芯金を用いなくても中空押出形材1の形状精度の良い曲げ加工が出来るという点で、中空押出形材1への芯金の挿入距離が長くなる長尺物の曲げ加工に好適であり、かつ複数回の曲げ加工を行う必要がある中空押出形材1にも本発明は適用しやすいという利点がある。 In the first step, at least a region of the left side wall 1c and the right side wall 1d that is substantially parallel to the bending radius direction of the hollow extruded profile 1 is recessed on the inner side of the cross section of the hollow extruded profile 1, and Since the predetermined concave groove 3 extending in the longitudinal direction of the hollow extruded shape member 1 is provided, it is difficult to cause deformation other than the region to be bent without using a cored bar, and the surface accuracy of the bent outer wall 1a. Etc., that is, it is easy to ensure the shape accuracy {that is, “break” of the bent outer wall 1a can be avoided}. As a result, there is an advantage that problems such as poor insertion of the cored bar during bending are less likely to occur. Moreover, it is suitable for the bending of a long object in which the insertion distance of the core bar into the hollow extruded member 1 is long because the hollow extruded member 1 can be bent with good shape accuracy without using the core bar. In addition, there is an advantage that the present invention can be easily applied to the hollow extruded shape member 1 that needs to be bent a plurality of times.
また、第2の工程(曲げ加工)においては、中空押出形材1の(曲げ外側壁1aと曲げ内側壁1bの幅B)及び(左側面壁1cと右側面壁1dの高さH)並びに断面の肉厚t(後記)の条件によっては、曲げ内側壁1bの曲げ終わり点周辺に断面外側方向へ飛び出すような凸しわが発生する。この凸しわを小さくするためには、所定の凹溝3の長さDが、曲げ金型4を用いて中空押出形材1を曲げる場合の曲げ開始点(図1に示す中空押出形材1を横断する線X上にある)から下記式(1)で規定した長さを満足するように設けるのが望ましい。
所定の凹溝3の長さDが、上記式(1)で規定した長さを満足するように設けるのが望ましい理由について、図3、図4を用いながら以下に説明する。 The reason why it is desirable to provide the length D of the predetermined groove 3 so as to satisfy the length defined by the above formula (1) will be described below with reference to FIGS.
曲げ内側壁1bの凸しわは、圧縮応力に起因して発生する。上記図1に示すように、中空押出形材1の曲げ開始点側については、あらかじめ曲げ金型4と接触しているために、断面外側方向への凸しわは発生しにくい。しかし、中空押出形材1の曲げ終わり点側については、加工途中段階で、曲げ内側壁1bの断面外側方向を向く凸変形を抑制する工具がないために、凸しわが発生する可能性がある。しかし、本発明者は、中空押出形材1に曲げ加工を施す場合の中空押出形材1の曲げ内側半径(r)方向に略平行な左側面壁1cや右側面壁1dの少なくとも曲げ加工を施す領域に、中空押出形材1の断面内側に凹み、かつ、中空押出形材1の長手方向に伸びる上記式(1)で規定した長さDの凹溝3を設けておくことで、「前記凸しわが大幅に緩和される」という新たな知見を得た。 The convex wrinkles of the bent inner wall 1b are caused by compressive stress. As shown in FIG. 1 above, since the bending start point side of the hollow extruded shape member 1 is in contact with the bending mold 4 in advance, the wrinkle toward the outer side of the cross section hardly occurs. However, on the bending end point side of the hollow extruded shape 1, there is no tool that suppresses the convex deformation facing the outer side of the cross section of the bending inner side wall 1b in the middle of processing, and thus wrinkles may occur. . However, the inventor performs at least bending of the left side wall 1c and the right side wall 1d substantially parallel to the bending inner radius (r) direction of the hollow extruded shape 1 when the hollow extruded shape 1 is bent. In addition, a concave groove 3 having a length D defined by the above equation (1) extending in the longitudinal direction of the hollow extruded shape member 1 and extending in the longitudinal direction of the hollow extruded shape member 1 is provided. The new knowledge that wrinkles are greatly eased.
そして、この凹溝3の長さDについては、矩形断面形材の圧壊試験結果から得た知見に応じて設定することで、凸しわを抑制できることを見出した。具体的には、図3(a)に示す供試材{アルミニウム合金6063−T1調質材、断面形状(寸法B×B、厚さt、角にC面付与)×長さH}を用いて、図3(b)に示すような縦圧壊試験{圧壊速度2mm/sec、無潤滑}を行なった結果、図4に示すような知見を得た。すなわち、しわの平均波長λave{図3(c)参照}は、左側面壁1cや右側面壁1d側面壁あるいは中リブ(後記図6参照)により支持される曲げ内側壁1bの幅Bの約0.8〜1.6倍程度になる(図4参照)。つまり、曲げ加工部とその管長手方向前後に、前記しわの波長分に相当する領域をカバーするように前記凹溝3を設定することで、曲げ内側壁1bに加わる圧縮応力を大幅に低減し、凸しわを抑制できる。この長さが上記式(1)で規定した長さDである。この凹溝3の長さDは、上記式(1)で規定した長さよりも長く設定しても問題なく曲げ加工可能であるが、当然変形の生じる領域が拡大することになる。したがって、できるだけ変形を受けない領域を長くする方が、曲げ加工後の形状精度確保には有利であるため、前記凹溝3の長さDは上記式(1)で示す範囲に設けるのが好ましいといえる。 And about the length D of this ditch | groove 3, it discovered that a convex wrinkle could be suppressed by setting according to the knowledge acquired from the crushing test result of the rectangular cross-section shape material. Specifically, the test material {aluminum alloy 6063-T1 tempered material, cross-sectional shape (dimension B × B, thickness t, C surface added to corner) × length H} shown in FIG. 3A is used. Then, as a result of conducting a longitudinal crush test as shown in FIG. 3B {crushing speed 2 mm / sec, no lubrication}, knowledge as shown in FIG. 4 was obtained. That is, the average wavelength λave of wrinkles {see FIG. 3C) is about 0. 0 of the width B of the bent inner wall 1b supported by the left side wall 1c, the right side wall 1d, the side wall, or the middle rib (see FIG. It is about 8 to 1.6 times (see FIG. 4). That is, by setting the concave groove 3 so as to cover the bending portion and the longitudinal direction of the tube so as to cover the region corresponding to the wrinkle wavelength, the compressive stress applied to the bending inner wall 1b can be greatly reduced. , Convex wrinkles can be suppressed. This length is the length D defined by the above formula (1). Even if the length D of the concave groove 3 is set longer than the length defined by the above formula (1), it can be bent without any problem, but naturally, the region where deformation occurs is enlarged. Therefore, since it is more advantageous to ensure the shape accuracy after the bending process, it is preferable that the length D of the concave groove 3 is provided in the range represented by the above formula (1). It can be said.
また、前記所定の凹溝3の長さDは、曲げ金型4を用いて中空押出形材1を曲げる場合の左側面壁1cや右側面壁1d上の曲げ開始点から下記式(1)で規定した長さを満足するように設けることが好ましい。何故ならば、この曲げ開始点よりも端部側に設けても問題ないが、変形領域は当然拡大することになる。逆に、曲げ開始点よりも曲げ加工部側に移動すると、曲げ加工時の左側面壁1cや右側面壁1dの変形のきっかけが生じにくくなり、これに起因して中空押出形材1の断面の変形が生じやすくなる。 The length D of the predetermined groove 3 is defined by the following formula (1) from the bending start point on the left side wall 1c and the right side wall 1d when the hollow extruded profile 1 is bent using the bending die 4. It is preferable to provide so as to satisfy the length. This is because there is no problem even if it is provided on the end side of the bending start point, but the deformation region is naturally enlarged. On the other hand, if it moves to the bending part side from the bending start point, the deformation of the left side wall 1c and the right side wall 1d during the bending process is less likely to occur, resulting in the deformation of the cross section of the hollow extruded shape member 1 Is likely to occur.
また、中空押出形材1の曲げ外側壁1aの破断を確実に回避するためには、中空押出形材1の中央(θ/2)の位置における下記式(2)で示す曲げ外側ひずみ量(ε)と中空押出形材1の一軸引張変形における破断伸び(δ)との関係が、下記式(3)を満足するのが望ましい。
すなわち、上記式(2)は、図1に示す幾何学的形状から、曲げ角度中央(θ/2)での曲げ外側ひずみ量(ε)を算出したものであり、本条件に一致するように移動金型6の回転中心P2と中空押出形材1の曲げ内側壁1bとの初期距Rの位置を定めることで、曲げ外側ひずみ量(ε)は素材の一軸引張における破断伸び(δ)以下にすることが可能であり、破断を確実に回避できることになる。 That is, the above formula (2) is obtained by calculating the bending outer strain amount (ε) at the bending angle center (θ / 2) from the geometric shape shown in FIG. initial distance by determining the position of the R, bending the outer strain amount of the rotation center P 2 and bending the side wall 1b of the cylindrical workpiece 1 of the movable mold 6 (epsilon) elongation at break in a tensile uniaxial material ([delta]) It is possible to make the following, and the breakage can be surely avoided.
また,曲げ加工される中空押出形材1の断面形状は,他部品との接合面の確保を考慮すれば、略矩形であることが望ましいが、左側面壁1cや右側面壁1dでの曲げ破断防止の観点からは断面の角に半径が3mm以上のRが設けられていることが望ましい。それは、図2に示す通り、曲げ加工方法を実施した場合に左側面壁1cおよび右側面壁1dは断面内側に凹むように変形し、この際、左側面壁1cと右側面壁1dのそれぞれの表面には局所的な曲げひずみが発生する。よって、断面の角に設けられるRが小さくなれば、この曲げひずみも大きくなり、曲げ破断が生じる可能性があるためである。 In addition, the cross-sectional shape of the hollow extruded profile 1 to be bent is preferably substantially rectangular in consideration of securing the joint surface with other parts, but it prevents bending fracture at the left side wall 1c and the right side wall 1d. From this point of view, it is desirable that R having a radius of 3 mm or more is provided at the corner of the cross section. As shown in FIG. 2, when the bending method is performed, the left side wall 1c and the right side wall 1d are deformed so as to be recessed inside the cross section, and at this time, the respective surfaces of the left side wall 1c and the right side wall 1d are locally formed. Bending strain occurs. Therefore, if R provided at the corner of the cross section is reduced, this bending strain also increases, and bending fracture may occur.
(他の実施形態)
図5は本発明の他の実施形態のアルミニウム合金製中空押出形材の曲げ加工方法を説明するための模式断面図である。図5において、曲げ角度θを図1に示す実施形態に比し小さくしている以外は、図1に同じである。なお、移動金型6の回転中心P2は、曲げ金型の曲げ半径中心P1と曲げ角度(θ)の中央(θ/2)の位置を結ぶ直線上に設定されている。これにより、曲げ加工終了位置での中空押出形材1の断面高さHの減少量を0にすることが出来る。
(Other embodiments)
FIG. 5 is a schematic cross-sectional view for explaining a method of bending an aluminum alloy hollow extruded shape according to another embodiment of the present invention. 5 is the same as FIG. 1 except that the bending angle θ is smaller than that of the embodiment shown in FIG. The rotation center P 2 of the movable mold 6 is set on a straight line connecting the position of the center (θ / 2) of the bending radius center P 1 and the bending angle of bending molds (theta). Thereby, the amount of reduction in the cross-sectional height H of the hollow extruded profile 1 at the bending end position can be reduced to zero.
なお、本実施形態においては、中空押出形材1の断面形状がロ字形(中リブのない矩形)の例について説明したが、必ずしもこれに限定されるものではない。例えば、図6に示すように、日形あるいは田形など中リブ1eを設けた断面形状であっても、適用可能である。なお、図6(a)に示す中リブ1eには第1工程における凹溝3を設けることは困難であることから、断面外周に位置する側面壁に凹溝3を設け、この変形に起因して中リブ1eを変形させることになる。また、図6(b)や図6(c)に示すような側面壁の中間位置に中リブ1eが接続される場合、これを中心に凹溝3を設けることで対応可能である。 In addition, in this embodiment, although the cross-sectional shape of the hollow extrusion shape material 1 demonstrated the example of a square shape (rectangle without a middle rib), it is not necessarily limited to this. For example, as shown in FIG. 6, the present invention can be applied even to a cross-sectional shape provided with a middle rib 1 e such as a day shape or a rice field. 6 (a), it is difficult to provide the concave groove 3 in the first step in the middle rib 1e. Therefore, the concave groove 3 is provided in the side wall located on the outer periphery of the cross section. Thus, the middle rib 1e is deformed. Moreover, when the middle rib 1e is connected to the intermediate position of the side wall as shown in FIG. 6B or FIG. 6C, it can be dealt with by providing the concave groove 3 around this.
また、本発明の曲げ加工に用いるアルミニウム合金製中空押出形材は、素材の強度面から6000系あるいは7000系合金で構成されていることが望ましい。また、さらに望ましくは、曲げ外側壁での曲げ破断を防止するために、少なくとも曲げ加工(第2の工程)前に材料到達温度が200℃以上、かつ、20sec以下(ゼロは含まない)の短時間の熱処理が施された後、熱処理後3時間以内に冷間状態で曲げ加工することが最も望ましい。このような曲げ加工(第2の工程)前熱処理を施した場合、素材の局部伸びが増加することが知られており、側面壁のように顕著な曲げ変形が生じる部位に使うことで、曲げ変形部での破断を防止できるといえる。 Moreover, it is desirable that the aluminum alloy hollow extruded shape used in the bending process of the present invention is made of a 6000 series or 7000 series alloy in view of the strength of the material. More preferably, in order to prevent bending fracture at the outer wall of the bend, at least the material arrival temperature is 200 ° C. or more and 20 sec or less (excluding zero) before the bending process (second step). It is most desirable to perform bending in a cold state within 3 hours after the heat treatment for a period of time. It is known that when such pre-bending (second process) heat treatment is performed, the local elongation of the material increases, and it can be bent by using it at sites where significant bending deformation occurs, such as side walls. It can be said that breakage at the deformed portion can be prevented.
また、本発明の曲げ加工方法は、特に曲げ半径が小さく、かつ、曲げ角度θが大きい加工での破断防止、形状精度確保の点で有効である。また、このように曲げ加工されたアルミニウム合金製中空押出形材は、軽量化の観点から自動車などの輸送機用フレーム構造体に好適である。特に、複数の曲げ角度θ=90°曲げ加工により形成したL字形、コ字形あるいはロ字形フレームなどに用いるのには好適であり、自動車用バッテリーフレームあるいは座席のフレーム構造体の一部に用いることが望ましい。 In addition, the bending method of the present invention is particularly effective in preventing breakage and ensuring shape accuracy in processing with a small bending radius and a large bending angle θ. Also, the aluminum alloy hollow extruded shape bent as described above is suitable for a frame structure for a transportation machine such as an automobile from the viewpoint of weight reduction. In particular, it is suitable for use in L-shaped, U-shaped or B-shaped frames formed by bending a plurality of bending angles θ = 90 °, and used for a part of a frame structure of an automobile battery frame or a seat. Is desirable.
本発明の曲げ加工方法の効果を確認するために、動的陽解法ソフトLS−DYNAを用いて、シミュレーションにて検証した。中空押出形材1として、長さL、□40mm(ロ字形、B=40mm×H=40mm、断面の角R=5mm、肉厚t=2mm)の7000系押出形材のT1調質材を用いた。予め側面壁1c、1dの高さH方向中央に、曲げ加工部の全長に渡る深さ5mmの凹溝3をプレス加工により設けたものとする。 In order to confirm the effect of the bending method of the present invention, the dynamic explicit software LS-DYNA was used and verified by simulation. As a hollow extruded shape 1, a T1 tempered material of a 7000 series extruded shape having a length L, □ 40 mm (B-shaped, B = 40 mm × H = 40 mm, cross-sectional angle R = 5 mm, wall thickness t = 2 mm) Using. It is assumed that a concave groove 3 having a depth of 5 mm is provided by pressing in the center of the side walls 1c and 1d in the height H direction over the entire length of the bent portion.
また、予め左側面壁1cと右側面壁1dのそれぞれの高さH方向中央に、
(a)長さD=120mmの凹溝3を設けた場合(すなわち、D=(r+H/2)θ+1.0B、発明例)、
(b)長さD=80mmの凹溝3を設けた場合(すなわち、D=(r+H/2)θ、発明例)、
(c)凹溝3を設けない場合(比較例)の3条件を準備した。
その他の条件は共通で、冷間加工、曲げ内側半径r=30mm、前記移動金型6の回転中心P2と中空押出形材1の曲げ内側壁1bとの初期距離R=60mm、曲げ角度θ=90(deg)としており、芯金は用いずに曲げ加工している。
In addition, in the center in the height H direction of each of the left side wall 1c and the right side wall 1d,
(A) When the concave groove 3 having a length D = 120 mm is provided (that is, D = (r + H / 2) θ + 1.0B, invention example),
(B) When the concave groove 3 having a length D = 80 mm is provided (that is, D = (r + H / 2) θ, invention example)
(C) Three conditions were prepared when the concave groove 3 was not provided (comparative example).
Other conditions are common: cold working, bending inner radius r = 30 mm, initial distance R = 60 mm between the rotation center P 2 of the moving mold 6 and the bending inner wall 1 b of the hollow extruded shape 1, bending angle θ = 90 (deg), and bending is performed without using a cored bar.
上記3条件による曲げ加工後の曲げ内側壁1bの凸しわの発生状態を図7に示し、曲げ外側壁1aのひずみ状態の評価結果を図8に示す。図8(a)、(b)及び(d)に示すように、凹溝3を設けた上記発明例(a)、(b)では、曲げ外側壁1aのひずみ量の発生が抑制される。すなわち、本願発明の適用により、曲げ外側壁1aの破断を回避しつつ、小さな曲げ半径での曲げ加工ができることが確証された。また、図7(a)に示すように、凹溝3の長さDを中空押出形材1の曲げ加工部長さに比べて長くした発明例では、曲げ内側壁1bの曲げ終わり部の凹凸しわ深さは0.3mmであり、凸しわは顕著に抑制されており、曲げ内側壁1bの所定の面精度が確保されていることがわかる。一方で図7(b)の曲げ内側壁1bの曲げ終わり部の凹凸しわ深さは、1.3mmであった。以上のように、本発明に係る曲げ加工方法を採用することで、冷間加工により比較的小さい曲げ半径で曲げ加工を行った場合でも、曲げ外側壁1aの破断を初めて抑制可能(曲げ外側壁1aの所定の面精度が確保可能)であることが判明した。さらに、凹溝3の長さDを前述した式(1)に示すような{例えば、上記発明例(a)のような}値に設定することで、曲げ内側壁1bおよび曲げ外側壁1aの面精度をより向上させることが可能である(すなわち、曲げ内側壁1bの凸しわの発生と曲げ外側壁1aの破断の両方までも抑制することができる)ことが判明した。 FIG. 7 shows the state of occurrence of wrinkles on the bent inner wall 1b after bending under the above three conditions, and FIG. 8 shows the evaluation result of the strain state of the bent outer wall 1a. As shown in FIGS. 8A, 8 </ b> B, and 8 </ b> D, in the above-described invention examples (a) and (b) provided with the recessed grooves 3, the generation of the strain amount of the bent outer wall 1 a is suppressed. That is, by applying the present invention, it was confirmed that bending with a small bending radius can be performed while avoiding breakage of the bending outer wall 1a. Further, as shown in FIG. 7 (a), in the invention example in which the length D of the groove 3 is made longer than the length of the bent portion of the hollow extruded profile 1, the uneven wrinkles at the bending end portion of the bending inner side wall 1b. The depth is 0.3 mm, and the wrinkles are remarkably suppressed, and it can be seen that the predetermined surface accuracy of the bent inner side wall 1b is ensured. On the other hand, the uneven wrinkle depth at the bending end portion of the bending inner wall 1b in FIG. 7B was 1.3 mm. As described above, by adopting the bending method according to the present invention, it is possible to suppress the fracture of the bending outer wall 1a for the first time even when bending is performed with a relatively small bending radius by cold working (bending outer wall). It was found that the predetermined surface accuracy of 1a can be ensured). Furthermore, by setting the length D of the concave groove 3 to a value as shown in the above-described formula (1) {for example, as in the above-described invention example (a)}, the bending inner wall 1b and the bending outer wall 1a It was found that the surface accuracy can be further improved (that is, both the occurrence of wrinkles on the bent inner side wall 1b and the fracture of the bent outer wall 1a can be suppressed).
1 アルミニウム合金製中空押出形材
1a 曲げ外側壁
1b 曲げ内側壁
1c 左側面壁
1d 右側面壁
1e 中リブ
2 押込み金型
3 凹溝
4 曲げ金型
5 背面抑え金型
6 移動金型
DESCRIPTION OF SYMBOLS 1 Aluminum alloy hollow extrusion 1a Bending outer wall 1b Bending inner wall 1c Left side wall 1d Right side wall 1e Middle rib 2 Pushing die 3 Concave groove 4 Bending die 5 Back surface holding die 6 Moving die
Claims (9)
この中空押出形材に曲げ加工を施す場合の前記中空押出形材の曲げ内側半径(r)方向に略平行な側面壁の少なくとも前記曲げ加工を施す領域に、前記中空押出形材の断面内側に凹み、かつ、前記中空押出形材の長手方向に伸びる所定の凹溝を設ける第1の工程と、
前記第1の工程後に、前記内側半径(r)の中心P1と前記曲げ加工を施す場合の曲げ角度(θ)の中央(θ/2)の位置を結ぶ直線上にあり、かつ、前記曲げ加工が施される領域から見て前記中心P1より遠い所定の位置に設定された点を回転中心P2とする、前記中空押出形材の曲げ外側壁に近接して設けられた移動金型を前記回転中心P2に対して回転させながら前記中空押出形材の曲げ加工を行う第2の工程と、
を有したことを特徴とするアルミニウム合金製中空押出形材の曲げ加工方法。 A bending method of an aluminum alloy hollow extruded section,
In the case of bending the hollow extruded profile, at least the region of the side wall that is substantially parallel to the bending inner radius (r) direction of the hollow extruded profile is formed on the inner side of the cross section of the hollow extruded profile. A first step of forming a recess and a predetermined recess extending in the longitudinal direction of the hollow extruded profile;
After the first step, there is on a straight line connecting the position of the center (θ / 2) Bending angle (theta) when subjected to the bending work with the center P 1 of the inner radius (r), and the bending processing the rotation center P 2 point set at a predetermined position distant from the center P 1 as seen from the region to be applied, the movable die provided near the bending outer wall of the cylindrical workpiece a second step of the performing bending of the cylindrical workpiece while rotating relative to the rotation center P 2,
A method for bending a hollow extruded profile made of an aluminum alloy, comprising:
H:側面壁の高さ
B:側面壁あるいは中リブにより支持される曲げ内側壁の幅 The length D in the longitudinal direction of the hollow extruded profile of the predetermined groove is defined by the following formula (1) from the bending start point on the side wall when the hollow extruded profile is bent using a bending die. 2. The method for bending an aluminum alloy hollow extruded section according to claim 1, wherein said length is satisfied.
H: Side wall height
B: Width of bent inner wall supported by side wall or middle rib
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2011255425A JP5616877B2 (en) | 2011-11-22 | 2011-11-22 | Bending method of aluminum alloy hollow extruded section, aluminum alloy hollow extruded section and automobile battery frame manufacturing method using this method, automobile battery frame and seat frame structure manufacturing method, and seat frame structure |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2011255425A JP5616877B2 (en) | 2011-11-22 | 2011-11-22 | Bending method of aluminum alloy hollow extruded section, aluminum alloy hollow extruded section and automobile battery frame manufacturing method using this method, automobile battery frame and seat frame structure manufacturing method, and seat frame structure |
Publications (2)
Publication Number | Publication Date |
---|---|
JP2013107117A JP2013107117A (en) | 2013-06-06 |
JP5616877B2 true JP5616877B2 (en) | 2014-10-29 |
Family
ID=48704453
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2011255425A Active JP5616877B2 (en) | 2011-11-22 | 2011-11-22 | Bending method of aluminum alloy hollow extruded section, aluminum alloy hollow extruded section and automobile battery frame manufacturing method using this method, automobile battery frame and seat frame structure manufacturing method, and seat frame structure |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP5616877B2 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105251821A (en) * | 2015-11-18 | 2016-01-20 | 宁波泰尔汽车部件有限公司 | Bending and blanking device |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR102195733B1 (en) | 2014-01-20 | 2020-12-28 | 삼성에스디아이 주식회사 | Curved secondary battery |
CN105251819B (en) * | 2015-11-18 | 2017-05-10 | 宁波泰尔汽车部件有限公司 | Bending and blanking device |
CN105251828B (en) * | 2015-11-18 | 2017-03-08 | 宁波泰尔汽车部件有限公司 | Automatically bending blanking device |
EP3399571A1 (en) * | 2017-05-05 | 2018-11-07 | Constellium Singen GmbH | Battery box for electric vehicles |
CN114798857B (en) * | 2022-04-19 | 2023-12-19 | 福建省富达精密科技有限公司 | Intelligent processing technology for seamless bending of television frame |
CN114850304B (en) * | 2022-04-28 | 2022-12-16 | 北京航空航天大学 | Combined forming method of aviation variable cross-section curvature component |
CN114749556B (en) * | 2022-05-17 | 2024-01-30 | 杭州萧山江海实业有限公司 | Aluminum-magnesium-zinc roll forming frame profile forming device |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6033176A (en) * | 1983-07-30 | 1985-02-20 | スズキ株式会社 | Frame for motorcycle |
JP2876985B2 (en) * | 1994-03-18 | 1999-03-31 | 日本軽金属株式会社 | Frame material, frame member, frame material for automobile, and method of manufacturing frame member |
JP3371589B2 (en) * | 1994-12-27 | 2003-01-27 | 日産自動車株式会社 | Aluminum extruded profile for bending to body structural members |
JP4320856B2 (en) * | 1999-08-09 | 2009-08-26 | 日本軽金属株式会社 | Hollow shape bending method, seat back frame manufacturing method and seat back frame structure |
-
2011
- 2011-11-22 JP JP2011255425A patent/JP5616877B2/en active Active
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105251821A (en) * | 2015-11-18 | 2016-01-20 | 宁波泰尔汽车部件有限公司 | Bending and blanking device |
Also Published As
Publication number | Publication date |
---|---|
JP2013107117A (en) | 2013-06-06 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5616877B2 (en) | Bending method of aluminum alloy hollow extruded section, aluminum alloy hollow extruded section and automobile battery frame manufacturing method using this method, automobile battery frame and seat frame structure manufacturing method, and seat frame structure | |
US10946427B2 (en) | Blank, forming plate, press formed article manufacturing method, and press formed article | |
US10603703B2 (en) | Method of manufacturing press-formed product, and press-formed product | |
KR101692658B1 (en) | Press-molding method | |
JP5151784B2 (en) | Center pillar outer panel manufacturing method and center pillar outer panel blank | |
JP5876786B2 (en) | Outer panel press molding method | |
CA2991565C (en) | Method and apparatus for manufacturing press component | |
EP3321026B1 (en) | Manufacturing method for a bent member | |
KR20160019498A (en) | Press molding method | |
RU2702671C1 (en) | Panel-like molded article and method of its production | |
KR101940165B1 (en) | Press-molding method and method for producing press-molded component | |
CA2772925C (en) | Curved parts and method for manufacturing the same | |
WO2017038579A1 (en) | Method for manufacturing stretch-flange-formed component | |
JPWO2015056351A1 (en) | Method for producing section steel whose cross-sectional shape changes in the longitudinal direction and roll forming apparatus | |
JP4376602B2 (en) | Metal material processing method and metal processed product | |
EP2390021B1 (en) | Hollow member | |
EP3085468B1 (en) | Press molding method | |
JP6319383B2 (en) | Manufacturing method of stretch flange molded parts | |
JP5868568B2 (en) | Bent member forming method and bent member manufacturing method | |
JP4102731B2 (en) | Bending method of aluminum alloy hollow profile | |
JP6079854B2 (en) | Bent member forming method and bent member manufacturing method | |
JP2017042825A (en) | Manufacturing method for molded component with stretch flange | |
JP2017056462A (en) | Mold for press forming and press forming method | |
JP5434047B2 (en) | Bent member forming method and bent member | |
JP5564013B2 (en) | Metal tube having joint seat surface and method of manufacturing metal tube having joint seat surface |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20130902 |
|
A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20140610 |
|
A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20140612 |
|
A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20140807 |
|
TRDD | Decision of grant or rejection written | ||
A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20140909 |
|
A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20140912 |
|
R150 | Certificate of patent (=grant) or registration of utility model |
Ref document number: 5616877 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |