576909 A7 B7 五、發明説明（i 【發明所屬之技術領域】 ----------------費…： (請先閲讀背面之注意事項再填寫本頁) 本發明係有關於一種組裝在熱水器等之熱交換器罐體 及其製造方法。 【習知技藝】 此種熱交換器罐體係具有一内裝有吸熱水管之胴部、及 一彎折於胴部邊緣而接合燃燒框體等另一箱體之接合凸緣 者；在接合凸緣與另一箱體相接合之狀態下，熱交換器罐 體與其他箱體緊密地結合。 ° 習知，接合凸緣係以接連於胴部且單純之彎折凸緣所構 成。在此，由於罐體為銅製，此種單純彎折凸緣係於用以 進行焊接之爐内施行退火，繼而在下一步驟之與另二箱體 斂合之斂合步驟中，易使該接合凸緣變形，故較難保持密 閉性。在此，迄今對接合凸緣焊接不繡鋼等補強材料，以 防止接合凸緣之變形（參考日本專利公開公報特開平6一 1Π92 號、特開 2000-18727 號）。 又，如第9圖所示，習知有令接合凸緣a為一具有接連 於胴部b之彎折凸緣部a卜及重疊彎折凸緣部之胴部b之 相反側之面之重疊凸緣部心之雙重彎折構造，以提高接合 凸緣之強度者。 σ 【發明所欲解決之課題】 如上述習知之前例一旦在接合凸緣焊接補強材料，則零 件數與步驟增加而提高成本。又，如上述習知之後例之雙 重彎折構造的接合凸緣a中，經不住來自圖下方之外力， 且由於強度不足而導致密閉性不足。 本紙張尺度適用中國國家標準（CNS) Α4規格（210X297公爱） -4- 576909 五、發明説明（2 ) 然而，熱交換器罐體係結合 ^ 造而成，而於製造各罐體半 5 —對罐體半部製 板部之链料侧緣彎折成一接人&:具有形成該胴部之平 成之蠻折模型，藉由冲床將使用沖床與冲模形 切筒狀h 床將趣料塞進冲模，彎折加工成半 切植。在此，一旦令接合凸緣為如上述雙重^ 則接合凸緣對於坯料之彎折 ^ 二* <抵才几增大，且交总姦* 彎曲不良或接合凸緣之形變。 產生 本發明有鑒於上述之問翻& , 1 n . ^ 碭，而以提供熱交換器罐體為第 …，该熱父換器罐體係以不使用補強材料而盡量可提 高接合凸緣之強度者；又，以 了棱 乂徒供一製造方法為第2課題， 該方法係在不產生管折不良與接合凸緣之形變下可順利 地進行用以製造罐體半部之柱料之彎折加工。 【解決課題之手段】 為解决上述第1課題，本發明為一種熱交換器罐體，係 具有胴邛肖f折於該胴部邊緣並接合於另一箱體的 接合凸緣者；其中，令該接合凸緣為一具有連接於胴部之 f折凸緣部、及—重疊於彎折凸緣之重疊凸緣部之多重彎 折構@在重疊凸緣部上形成有一接合於胸部的接觸部 者。 又，為解決上述之第2課題，本發明為一種熱交換器罐 體之製造方法，係將半切筒狀之一對罐體半部結合者，其 係於製造各罐體半部時，於具有形成胴部之平板部之坯料 之侧緣彎折成前述多重彎折構造之接合凸緣後，使用冲床 與冲模形成之彎折冲模型，藉由冲床將坯料塞進冲模而彎 本紙張尺度適用中國國家標準（CNS) M規格Ul〇X297公釐） (請先閲讀背面之注意事項再填寫本頁) tr-i 擎 折加工成半切筒狀者，其 從板厚方A U ^务明，於冲模模型成一 在藉由溝部來限制接合凸緣部：r而可接納之溝部，而 工者。 mp歪斜之狀態下來進行彎折加 八外1 #明之熱交換器罐體，將施加於接合凸緣之一部 :』由接觸部而由胴部承受，而可提高強度。此時， 但—Γ重疊㈣部之邊緣作為制部而使其制於胴部， 縮：此使重疊凸緣部之末端沿著胴部彎曲而形成上述之接 ―和則接觸於胴部之接觸面積增大，更可提高強度。進 =右將接觸部結合於胴部，更可大幅地提高接合凸緣 t強度。 又’亦可將重疊凸緣部重疊於與彎折凸緣部之胴部相反 之：’使重疊凸緣部之末端沿著胴部内璧面彎折而形成接 觸部；此時一旦在胴部與接觸部之間產生空隙，則燃燒排 孔中之水分等將冷凝而積存於空隙，因此容易心而使耐 久=憂差。相對於此，若將重疊凸緣部重疊於彎折凸緣部 之胴部之面，而使上述之接觸部接觸於胴部之外壁面，縱 使胴部與接觸部間產生空隙也不致積存水份，而可提高耐 久性。 又根據本發明，令接合凸緣成多重彎折構造，即使接 :凸緣對於坯料之彎折加工之抵抗變大，接合凸緣藉由冲 模之溝部不致於板厚方向產生歪斜而可彎折，而可順利地 進行彎折加工。 【發明之實施態樣】 折 彎 沿 所 面576909 A7 B7 V. Description of the invention (i [Technical Field to which the Invention belongs] ---------------- Fee ...: (Please read the notes on the back before filling this page) The invention The invention relates to a heat exchanger tank body assembled in a water heater and the like, and a manufacturing method thereof. [Knowledge] This heat exchanger tank system has a crotch portion with a water suction pipe inside, and a bent edge of the crotch portion. Those who join the joint flange of another box, such as the combustion frame; in the state where the joint flange is joined with the other box, the heat exchanger tank is tightly combined with the other box. ° Known, the joint projection The edge is composed of simple bent flanges connected to the crotch. Here, because the tank is made of copper, this simple bent flange is annealed in the furnace used for welding, and then in the next step In the convergence step of convergence with the other two cases, the joint flange is easily deformed, so it is difficult to maintain the tightness. Here, welding materials such as stainless steel have been welded to the joint flange to prevent the joint flange Deformation (refer to Japanese Patent Laid-Open Publication No. 6-1Π92, JP 2000-18 No. 727). Also, as shown in FIG. 9, it is known that the joint flange a is the opposite of the flange portion a having the flange portion b connected to the flange portion b and the flange portion b overlapping the flange portion b. The side of the double-folded structure that overlaps the center of the flange portion to increase the strength of the joint flange. Σ [Problem to be solved by the invention] As in the previous example, once the reinforcing material is welded to the joint flange, the number of parts As the number of steps increases, the cost is increased. In addition, the joint flange a of the double-folded structure, as in the above-mentioned conventional example, cannot withstand external forces from the bottom of the figure, and the tightness is insufficient due to insufficient strength. This paper standard applies China National Standard (CNS) Α4 Specification (210X297 public love) -4- 576909 V. Description of the Invention (2) However, the heat exchanger tank system is made by combining ^, and each tank body is made of 5-half of the tank body The side edge of the chain material of the plate-making part is bent into a contact &: it has a heisei model that forms the crotch. The punch will use a punch and a die-shaped cylindrical h-bed to insert the fun into the punch. Bend into half-cut plants. Here, once the joint is made convex For the double ^ as described above, the bending of the joint flange to the blank ^ two * < the number of arrivals increases, and the total cross-section * poor bending or deformation of the joint flange. The present invention is made in view of the above problems & , 1 n. ^ 砀, and the provision of heat exchanger tanks is the first ... The heat-exchanger tank system is designed to increase the strength of the joint flange as much as possible without the use of reinforcement materials; A manufacturing method is the second problem, and this method can smoothly perform the bending processing for manufacturing the column material for the half of the tank body without causing tube breakage failure and deformation of the joint flange. [Means for solving the problem] is In order to solve the above-mentioned first problem, the present invention is a heat exchanger tank having a joint flange folded at the edge of the crotch and joined to another box; wherein the joint flange is a A multi-folded structure having an f-folded flange portion connected to the crotch portion and an overlapped flange portion overlapped with the folded flange @A contact portion that is connected to the chest is formed on the overlapped flange portion. In addition, in order to solve the second problem described above, the present invention is a method for manufacturing a heat exchanger tank, which is a combination of a half-cut cylindrical pair of tank halves. After bending the side edge of the blank with the flat part forming the crotch into the joint flange of the multiple bending structure, a bending punch model formed by a punch and a die is used to insert the blank into the die by the punch to bend the paper. Chinese National Standard (CNS) M specification Ul XX297 mm) (Please read the precautions on the back before filling this page) tr-i The machine is folded into a half-cut tube, the thickness of which is AU ^ The die is modeled as a groove portion that can be accepted by the groove portion to limit the joint flange portion, and the worker. When the mp is in a skewed state, bend it and add eight outer 1 # Ming heat exchanger tanks, which will be applied to one of the joint flanges: "The contact part and the crotch part will bear it, which can increase the strength. At this time, but-the edge of the overlapped ㈣ part is made as the control part and made on the 胴 part, and the contraction: this makes the end of the overlapping flange part bend along the 胴 part to form the above connection-and the contact that contacts the 胴 part The larger the area, the higher the strength. Forward = right The contact portion is combined with the crotch, which can greatly increase the strength of the joint flange t. Also, 'the overlapping flange portion can also be overlapped with the opposite of the bent portion of the flange portion:' make the end of the overlapping flange portion bend along the inside surface of the flange portion to form a contact portion; once in the flange portion If a gap is generated between the contact part and the water in the combustion exhaust hole, it will condense and accumulate in the gap, so it is easy to take care and make the durability = worry. On the other hand, if the overlapping flange portion is superposed on the surface of the crotch portion of the bent flange portion, and the above-mentioned contact portion is brought into contact with the outer wall surface of the crotch portion, even if a gap occurs between the crotch portion and the contact portion, water will not be accumulated It can improve durability. According to the present invention, the joint flange is made into a multi-folded structure. Even if the joint flange has greater resistance to the bending process of the blank, the joint flange can be bent by the groove portion of the die so that the plate thickness direction is not skewed. , And can be smoothly processed. [Implementation aspect of the invention] Bend along all sides
— (請先閲讀背面之注意事項再填寫本頁) t 576909 五、發明説明（ 么第1圖係顯不組裝於熱水器之熱交換器。此熱交換器係 =吸熱水官（未圖示）而形成，該吸熱水管係具備有一 角筒狀月同部10之銅製罐體1，而罐體1内包含有數個熱交 奐翼片2 ’而胴部i G之下半部外周繞捲有給水連絡管3， 过給水連絡管3則連接於吸熱水管之上游端，而吸熱水 管下游端連接著給熱水管4。 _於胴部10下端緣-折有一下凸緣u，其係接合於未圖 不而作為另一箱體之燃燒框體者，而罐體1係按該下凸緣 11而歛合於燃燒框體上。又，於彎折於胴部1G之上端緣 之上凸緣12點焊有一凸緣板13，並於罐體i藉該凸緣板 13而與一排氣框體相接合。 如第2圖所示’上述下凸緣u形成一雙重f折之構造， 係具有連接於胴部1()之料凸緣部na、與重叠於該弯折 緣邛11 a之重疊凸緣部丨〗b ;於重疊凸緣部11 &中更形 成有一接合於胴部10之接觸部Uce在第2圖所示之形態 中’將重疊凸緣部11b重疊f折於f折凸緣Ua之靠近綱 部：〇側面處’並使重疊凸緣部Ub之末端沿著胴部之外璧 面彎折而形成接觸部11 c。 再來’如第3圖所示，重疊凸緣部爪重疊弯折於與 =凸緣部Ha之胴部10之相對面，並使重叠凸緣部爪 著胴部10之内壁面彎折而形成接觸部Uc;又如第4圖 示’亦可使重疊凸緣部llb之邊緣接觸著胴部1()之外壁 而重疊f折，而將重疊凸緣部Ub之邊緣形成接觸部J 在第2圖至第4圖中任一形態中’係構建成一雙重弯 本紙張尺度適用中國國家標準（CNS) A4規格（210X297公釐）— (Please read the precautions on the back before filling out this page) t 576909 V. Description of the invention (the first picture shows the heat exchanger that is not assembled in the water heater. This heat exchanger = water absorption officer (not shown) Thus, the hot-water pipe is provided with a copper tank 1 having a rectangular cylindrical moon-shaped part 10, and the tank 1 contains a plurality of heat-exchanging fins 2 ', and the lower part of the crotch part i G is wound around the outer periphery. The feed water connection pipe 3, the feed water connection pipe 3 is connected to the upstream end of the hot water pipe, and the downstream end of the hot water pipe is connected to the hot water pipe 4. _ At the lower edge of the crotch 10-a flange u is folded, which is connected to Not shown as a combustion frame of another box, and the tank 1 is converged on the combustion frame according to the lower flange 11. Also, it is convex above the end edge bent over the crotch 1G. A flange plate 13 is spot-welded at the edge 12, and the can body i is joined to an exhaust frame by the flange plate 13. As shown in FIG. 2, the above-mentioned lower flange u forms a double f-folded structure. , Has a flange portion na connected to the crotch portion 1 (), and an overlapping flange portion overlapping the bending edge a11 a 丨 b; at the overlapping flange portion 11 & am p; Zhong Geng has a contact portion Uce joined to the crotch portion 10 in the form shown in FIG. 2 'overlapping the overlapping flange portion 11b and f folding the f-folding flange Ua near the outline portion: 0 side surface' and The contact portion 11 c is formed by bending the end of the overlapping flange portion Ub along the outside surface of the ridge portion. Then, as shown in FIG. 3, the overlapping flange portion claw is folded and overlapped with the flange portion Ha. The facing surface of the crotch portion 10, and the overlapping flange portion is bent against the inner wall surface of the crotch portion 10 to form a contact portion Uc; as shown in the fourth figure, the edge of the overlapping flange portion 11b may also contact the crotch. The outer wall of the part 1 () is overlapped by f-folds, and the edge of the overlapping flange part Ub forms a contact part J. In any of the forms in Figs. 2 to 4, it is constructed as a double bend. (CNS) A4 size (210X297 mm)
發明說明（ 構w ’以提鬲下凸緣11之剛性，同時藉接觸部11 c來使附 加於下凸緣11之部分外力由胴部10來承受，提升下凸緣 11之強度。因此，就算不加裝習知例般之補強材料，亦可 防止下凸緣11在燃燒框體之歛合步驟中變形，而保持其氣 密性。 ' ' 又，如第2圖與第3圖之實施樣態所示，使重疊凸緣[Explanation of the invention] The structure w 'is used to increase the rigidity of the lower flange 11, and at the same time, the contact portion 11c is used to cause the external force added to the lower flange 11 to be received by the flange 10, thereby improving the strength of the lower flange 11. Even if no conventional reinforcing material is added, the lower flange 11 can be prevented from deforming in the convergence step of the combustion frame, and its airtightness can be maintained. '' Also, as shown in FIG. 2 and FIG. 3 Shown in the form, overlapping flanges
1 1 U 之末端彎折而形成帶狀接觸部11c，增加相對於胴部 10之接觸面積，而更提升了下凸緣11之強度。又，按第3 圖之實施樣態，由於接觸部11c是位在胴部1〇之内壁面 側，因此在胴部10與接觸部llc之間產生空隙，而使燃燒 時排氣所產生之凝結水等滯留於空隙中而易造成腐蝕。而 相對於第2圖與第4圖之實施樣態，則係將接觸部丨丨c置 於胴部1 0之外壁面侧，因此就算胴部丨〇與接觸部丨丨c之 間產生有空隙也不會滯留水分，提高其耐久性。又，第2 圖乃至第4圖中任一實施樣態，均使接觸部Uc接合於胴 部1〇，而大幅地提升下凸緣U之強度。再者，罐體丨宜 為使一對呈半切筒狀之罐體半部丨a，丨a於爐中經由焊接而 結合成者（參照第1圖），且於該焊接步驟中將該接觸部 11C結合於胴部1 〇者。 如第5圖所示，各罐體半部ia係將具有胴部之平板 部之述料1 (銅板）之兩側邊緣彎折成下凸緣1 1與上凸 緣12後，再將坯料1 ’彎折加工成半切筒狀而成。於下凸 緣11之彎折時，如第6圖所示，先將坯料丨，之邊緣做镶 邊加工而形成重疊凸緣部11 b，再將鑲邊部做彎折加工而 本紙張尺度適用中國國家標準（CNS) A4規格（210X297公釐） tr (請先閲讀背面之注意事項再填寫本頁) 576909 A7 --- B7_ 五、發明説明(6 ) " ' " '~—~ (請先閲讀背面之注意事項再填寫本頁) 使重疊凸緣部llb形成為重疊彎折之彎折凸_山。在 此，第4圖之實施樣態雖有必要使鑲邊加工t寬度與彎折 加工之寬度正確地配合；然而在第2圖與第3圖之實施樣 態則因為尺寸與加工時之差異可透過接觸部11c之寬度變 化來調整，使得加工變得容易。 為了製造罐體半部la之述料折加工，係使用如 第7圖與第8圖所示之冲床1〇〇與冲冑1〇1所形成之彎折 沖模型，藉由冲床100如第8(八）至8⑻圖所示將述料^ 擠入冲模1(H。在此，由於在上凸緣12上形成與罐體半部 la之角部一致之缺口 12a，因此上凸緣12在彎折加工時並 無產生阻力；但由於下凸緣丨丨係如上述之雙重彎折構造且 並無形成缺口，因此下凸緣丨丨相對於彎折加工之阻力變 大，而容易於罐體半部la之角部產生有下凸緣u之邊紋 之形變。 在此，本實施樣態在冲模101之本體裝有一如第7圖所 示之凸緣壓板1 〇 1 a ,從厚板方向之兩側將下凸緣丨丨夾於 冲模本體與凸緣壓板l〇la間而形成一可收納之溝部 101 b。藉此，可透過溝部丨〇丨b來限制下凸緣丨丨部不會歪 斜於厚板方向之狀態下來進行坯料丨，之彎折加工，使得不 會在下凸緣11產生邊紋之類的形變。於彎折加工時，雖於 靠近胴部10之下凸緣U之外壁面施予強力，但如第2圖 所示，由於以接觸部；He覆蓋著此部分，有益於防止損壞 之發生。 又’在本實施樣態中，係將冲模1 〇 i之凹入深度L設 本紙張尺度適用中國國家標準（CNS) A4規格（210X297公董） -9- 576909 五、發明説明（ 定在罐體半部u角部之彎曲半徑尺的2 5倍以上。習知之 凹入深度L均在角部之f曲半徑“ 2倍左右所以在如 第8⑼圖所示之狀態下完成變折加工後，將使链料i，益法 擠入冲才莫HH的部分而變成X字形狀。針對此問題，本實 施態是進行到如第8⑻圖之狀態以將坯料i，擠入冲模 HH，不致產生彎折不良。為了確實地防止彎折不良產生： 希望可以將冲模101之凹入深度設定在罐體半部h之角部 的3倍以上。再者，本實施態樣雖然是配合罐體半部“ 之兩各角部而將冲模1〇1分隔成兩個，當然亦可使用1;字 型之單一冲模。 又，如第1圖所示，僅將下凸緣丨丨形成雙重彎折構造， 但亦可將上凸緣12做成和下凸緣11同一之雙重彎折構 造，而省略凸緣板13。進而，可於彎折凸緣部lla上重疊 彎折兩個以上重疊凸緣部11 b，而形成具三重以上之彎折 構造。 【圖式之簡單說明】 第1圖係顯示具有本發明罐體之熱交換器例之立體圖。 第2圖係本發明罐體第1實施樣態之接合凸緣部分之戴 面圖。 第3圖係本發明罐體第2實施樣態之接合凸緣部分之戴 面圖。 第4圖係本發明罐體第3實施樣態之接合凸緣部分之載 面圖。 第5圖係顯示用以彎折成接合凸緣之述料之立體圖。 本紙張尺度適用中國國家標準（CNS) A4規格（210X297公爱） -10· ---------------…tp--------------- (請先閲讀背面之注意事項再填寫本頁) 576909 A7 B7 五、發明説明 第6圖係顯示接合凸緣之彎折步驟圖。 第7圖係顯示本發明方法之實施上所使用之、彎折沖模 之立體圖。 第8圖係顯示經由彎折沖模（A)到（E)之坯料之彎折加工 由開始階段到完工為止之狀態之步驟圖。 第9圖係習知例之接合凸緣部分之截面圖。 【標號之說明】 1…罐體 Γ...坯料 2.. .熱交換翼片 3.. .給水連接管 4…給熱水管 10…胴部 11·.·接合（下）凸緣 11 a·.·彎折凸緣部 lib…重疊凸緣部 11c...接觸部 12···上凸緣 12a".缺口 13.. .凸緣板 100…冲床 101.. .冲模 101a···凸緣壓板 101b·.·溝部 本紙張尺度適用中國國家標準（CNS) Α4規格（210X297公釐） -I-…-…？ί (請先閲讀背面之注意事項再填寫本頁) -訂- 章 -11 -The end of 1 1 U is bent to form a strip-shaped contact portion 11c, which increases the contact area with respect to the crotch portion 10, and further increases the strength of the lower flange 11. In addition, according to the embodiment shown in FIG. 3, since the contact portion 11c is located on the inner wall surface side of the crotch portion 10, a gap is generated between the crotch portion 10 and the contact portion 11c, and the exhaust gas generated during combustion is generated. Condensed water and so on stay in the gap and easily cause corrosion. In contrast to the implementation patterns of FIGS. 2 and 4, the contact portion 丨 丨 c is placed on the side of the wall outside the ridge portion 10, so even if there is a gap between the ridge portion 丨 〇 and the contact portion 丨 丨 c, The voids do not retain moisture, which improves its durability. In addition, in any of the second embodiment to the fourth embodiment, the contact portion Uc is joined to the crotch portion 10, and the strength of the lower flange U is greatly improved. Furthermore, the tank body 丨 should preferably be a pair of tank body halves having a half-cut cylindrical shape 丨 a, 丨 a combined by welding in a furnace (refer to FIG. 1), and contacting this in the welding step Part 11C is connected to the crotch 10. As shown in FIG. 5, each half of the tank body ia is formed by bending both sides of the material 1 (copper plate) of the flat plate portion with the crotch into the lower flange 11 and the upper flange 12, and then the blank 1 'Bently processed into a half-cut tube. When the lower flange 11 is bent, as shown in FIG. 6, the edges of the blank 丨 and the edge are first processed to form the overlapping flange portion 11 b, and then the flanged portion is subjected to the bending processing to the paper size. Applicable to China National Standard (CNS) A4 specification (210X297 mm) tr (Please read the precautions on the back before filling this page) 576909 A7 --- B7_ V. Description of Invention (6) " '"' ~ — ~ (Please read the precautions on the back before filling in this page.) The overlapping flange portion 11b is formed as a folded convex ridge of overlapping bends. Here, although it is necessary to match the width of the trimming process t and the width of the bending process in the embodiment of Figure 4, the implementation of Figures 2 and 3 is different because of the difference in size and processing. It can be adjusted by changing the width of the contact portion 11c, making processing easier. In order to manufacture the material folding process of the half body la of the tank body, a bending punching model formed by a punch 100 and a punch 101 as shown in FIGS. 7 and 8 is used. (8) to 8), the material ^ is squeezed into the die 1 (H. Here, because the upper flange 12 is formed with a notch 12a consistent with the corner of the can body half la, the upper flange 12 is There is no resistance during the bending process; but because the lower flange 丨 丨 is a double bending structure as described above and no gap is formed, the resistance of the lower flange 丨 丨 to the bending process becomes larger, and it is easier for the can The corner of the body half la has a deformation of the edge of the lower flange u. Here, in this embodiment, a flange pressing plate 1 〇1 a as shown in FIG. The lower flange 丨 丨 is sandwiched between the die body and the flange pressing plate 10la on both sides of the plate direction to form a storable groove portion 101 b. By this, the lower flange can be restricted through the groove portion 丨 〇 丨 b The parts are not skewed in the direction of the thick plate, and the blank is processed in a bending process, so that no deformation such as fringe is generated in the lower flange 11. In the bending process, although a strong force is applied to the outer wall surface of the flange U near the lower part of the crotch 10, as shown in FIG. 2, since the contact portion is covered with He, this portion is useful for preventing damage from occurring. Also, in this embodiment, the recess depth L of the die 10i is set to the paper size applicable to the Chinese National Standard (CNS) A4 specification (210X297 public director) -9- 576909 5. Description of the invention (determined in the tank The bending radius of the corner of the body half u is more than 25 times. The depth of recess L is about 2 times of the radius of f of the corner, so after the bending process is completed in the state shown in Figure 8 , The chain material i will be squeezed into the part of the punch HH and turned into an X shape. In response to this problem, this embodiment is carried out to the state shown in Figure 8 to squeeze the blank i into the die HH, so that Defective bending occurs. In order to reliably prevent the occurrence of deficient bending, it is desirable to set the recessed depth of the die 101 to more than three times the corner of the can half h. Further, although this embodiment is adapted to the can body The "half" has two corners to separate the die 10 into two. Of course, 1 can also be used. A single die with a font. As shown in FIG. 1, only the lower flange 丨 丨 is formed into a double-folded structure, but the upper flange 12 may be made into the same double-folded structure as the lower flange 11. , And the flange plate 13 is omitted. Further, two or more overlapping flange portions 11 b can be folded on the folded flange portion 11a to form a folded structure with three or more layers. Fig. 1 is a perspective view showing an example of a heat exchanger having a can body of the present invention. Fig. 2 is a wearing surface view of a joint flange portion of the first embodiment of the can body of the present invention. Fig. 3 is a second view of the can body of the present invention. Wearing surface view of the joining flange part of the embodiment. Figure 4 is a sectional view of the joining flange part of the third embodiment of the tank body of the present invention. Fig. 5 is a perspective view showing the material used for bending into a joint flange. This paper size applies to China National Standard (CNS) A4 specification (210X297 public love) -10 · ---------------... tp ------------- -(Please read the notes on the back before filling this page) 576909 A7 B7 V. Description of the invention Figure 6 shows the bending steps of the joint flange. Figure 7 is a perspective view showing a bending die used in the implementation of the method of the present invention. Fig. 8 is a step chart showing the state of the bending process of the blank through the bending dies (A) to (E) from the initial stage to completion. Fig. 9 is a sectional view of a joint flange portion of a conventional example. [Description of reference numerals] 1 ... tank Γ ... blank 2 .. heat exchange fins 3 .... water supply connection pipe 4 ... water supply pipe 10 ... 胴 11 ··· joining (lower) flange 11 a ··· Folded flange part lib ... overlapping flange part 11c ... contact part 12 ··· upper flange 12a " .notch 13. .flange plate 100 ... punch 101 .... die 101a ... Flange pressure plate 101b ··· Groove The paper size is applicable to Chinese National Standard (CNS) A4 specification (210X297mm) -I -...-...? ί (Please read the notes on the back before filling out this page) -Order-Chapter -11-