WO2012144490A1 - Method for manufacturing threaded bottle can and manufacturing device - Google Patents

Abstract

Provided are a method for manufacturing a threaded bottle can and a manufacturing device with which a thread forming process can be performed without scratching an inside surface coating and which improves resealing operability. The opening part of a cylindrical body with a bottom is reduced in diameter and a shoulder part (2) is formed, and above this shoulder part (2), a cylindrical part (11) that widens in diameter to an outside diameter between the high parts and low parts of the threads and a tapered part (14) in which the diameter is progressively reduced toward the opening end part (13) from the upper end of the cylindrical part (11) are formed. A thread forming process is carried out on the cylindrical part (11), and the outside diameter of a part from the upper edge of the first high part of the threads formed in the cylindrical part (11) to a part of the tapered part (14) is processed to a diameter equal to the low parts of the threads or a diameter smaller than the same.

Description

ねじ付きボトル缶の製造方法及び製造装置Method and apparatus for manufacturing a screw can

　本発明は、キャップが螺着されるねじを有するねじ付きボトル缶の製造方法及び製造装置に関する。
　本願は、２０１１年４月１９日に日本国に出願された特願２０１１－０９３０８５号に基づき優先権を主張し、その内容をここに援用する。The present invention relates to a method and an apparatus for manufacturing a threaded bottle can having a screw on which a cap is screwed.
Priority is claimed on Japanese Patent Application No. 2011-093085, filed on April 19, 2011, the content of which is incorporated herein by reference.

　飲料等の内容物が充填される容器として、雄ねじを有する口金部にキャップが螺着されるアルミニウム合金製のボトル形状の缶（ボトル缶）が知られている。
　このボトル缶は、特許文献１又は特許文献２に開示されるように、アルミニウム合金板を絞り加工及びしごき加工（ＤＩ成形）により底板部と円筒状側面部とが一体となった有底円筒体に成形し、その開口部を縮径して肩部を形成するとともに、肩部よりも上方部分にねじ成形のための拡径した筒状部を形成した後、この筒状部にねじ成形加工を施し、開口端部にカール部形成加工を施す等により製造される。An aluminum alloy bottle-shaped can (bottle can) is known as a container filled with contents such as beverages, in which a cap is screwed to a mouthpiece having an external thread.
As disclosed in Patent Document 1 orPatent Document 2, this bottle can has a bottomed cylindrical body in which a bottom plate portion and a cylindrical side portion are integrated by drawing and ironing (DI molding) an aluminum alloy plate. And forming a shoulder portion by reducing the diameter of the opening and forming a diameter-increased cylindrical portion for thread formation in a portion above the shoulder portion, and then thread-forming the cylindrical portion And the curled portion is formed at the open end.

　また、この種のボトル缶は、開口部を縮径して加工する前の有底円筒体の内外面に塗装が施されるが、特に内面塗装に対し損傷を与えないで開口部を加工する方法として、特許文献３記載の方法がある。
　この特許文献３には、ねじ成形加工する前の中間成形体において、肩部から少なくとも二段以上に絞り加工して口部を形成することにより、開口端から二段目の部位に、ねじの山径と谷径との中間径の外径を有する筒状部を形成しておき、この筒状部を内駒と外駒で挟み込んでねじ成形加工することが記載されている。In addition, although this type of bottle can is coated on the inner and outer surfaces of the bottomed cylindrical body before processing by reducing the diameter of the opening, in particular the opening is processed without damaging the inner surface coating As a method, there is a method described inPatent Document 3.
According to thispatent document 3, in the intermediate molded body before thread forming processing, the opening is formed by drawing at least two or more steps from the shoulder portion, thereby forming a screw in the second step from the open end. It is described that a tubular portion having an outer diameter which is an intermediate diameter between a mountain diameter and a valley diameter is formed, and the tubular portion is screw-formed by being sandwiched between an inner piece and an outer piece.

米国特許第５７０４２４０号明細書U.S. Pat. No. 5,704,240特開平５－２２９５４５号公報JP-A-5-229545特開２００２－６６６７４号公報JP 2002-66674 A

　特許文献３記載の方法によれば、ねじ成形加工前の筒状部の外径が、ねじの山径と谷径との中間径に形成されていることから、ねじ成形加工による塑性変形が小さく、塗装の損傷が低減されると期待できる。
　ところで、この種のボトル缶は、開栓した後に、再度キャップを被せてシールすることができるが、この再度のシール操作がし易いものであることも求められている。According to the method described inPatent Document 3, since the outer diameter of the cylindrical portion before screw forming is formed to be an intermediate diameter between the peak diameter and the valley diameter of the screw, plastic deformation due to screw forming is small. It can be expected that paint damage will be reduced.
By the way, although this kind of bottle can can be covered again and sealed after being opened, it is also required that the second sealing operation is easy.

　本発明は、このような事情に鑑みてなされたもので、内面塗装に損傷を与えることなくねじ成形加工することができるとともに、再度のシール操作性も向上させたねじ付きボトル缶の製造方法及び製造装置を提供することを目的とする。The present invention has been made in view of such circumstances, and it is possible to screw-process without damaging the inner surface coating, and also to provide a method for manufacturing a screw can with improved sealing operability. It aims at providing a manufacturing apparatus.

　本発明者は、開栓した後の再度のシール操作について鋭意研究した結果、キャップの内面側のねじ条の最下端がボトル缶のねじの一山目と二山目との間の谷部に円滑に螺合すれば、再度のシール操作を容易にすることができると考えた。これに対して、特許文献３記載の方法では、ねじ成形加工前の筒状部の外径が、ねじの山径と谷径との中間径に形成され、この中間径の位置でねじ成形加工していることから、カール部からねじの一山目の一周分までに至るテーパ部（特にねじ始まり部の手前の部分）において、ねじの谷径より大きな外径を有する未加工部が残ってしまい、この未加工部がキャップを再度シールする際の抵抗となっていることを見出した。
　そこで、再度のシール操作を容易にするために、このカール部からねじの一山目の一周分までに至るテーパ部にねじの谷径よりも大きい部分を残さないようにねじ成形加工することが重要であるとの結論に至り、以下のような解決手段とした。As a result of intensive research on the re-sealing operation after opening the present invention, the lower end of the inner side thread of the cap is in the valley between the first and second peaks of the screw of the bottle can. I thought it would be possible to facilitate the re-sealing operation by screwing in smoothly. On the other hand, in the method described inPatent Document 3, the outer diameter of the cylindrical portion before screw forming is formed to be an intermediate diameter between the peak diameter and the valley diameter of the screw, and screw forming at the position of this intermediate diameter Because of this, in the tapered portion (especially in the portion just before the screw start portion) from the curled portion to the first turn of the screw, an unmachined portion having an outer diameter larger than the valley diameter of the screw remains. It turned out that this un-processed part became resistance at the time of sealing a cap again.
Therefore, in order to facilitate the sealing operation again, it is possible to use a screw forming process so as not to leave a portion larger than the valley diameter of the screw in the tapered portion from the curled portion to one round of the first ridge of the screw. It came to the conclusion that it was important, and made it the following solution.

　本発明のねじ付きボトル缶の製造方法は、有底筒状体の開口部を縮径して肩部を形成するとともに、この肩部よりも上方に、ねじの山径と谷径との間の外径の筒状部と、該筒状部の上端から開口端部に向けて漸次縮径するテーパ部とを形成しておき、前記筒状部にねじ成形加工するとともに、該筒状部に形成されるねじの一山目の上縁から前記テーパ部の一部に至る部分の外径を、ねじの谷径と同じか、それより小さい径に加工することを特徴とする。According to the method of manufacturing a threaded bottle can of the present invention, the diameter of the opening of the bottomed cylindrical body is reduced to form a shoulder, and between the peak diameter and the valley diameter of the screw above this shoulder A tubular portion having an outer diameter of 50 mm and a tapered portion whose diameter gradually decreases from the upper end of the tubular portion toward the opening end, and the tubular portion is screw-formed and the tubular portion The outer diameter of the portion from the upper edge of the first ridge of the screw formed to the part of the tapered portion is processed to a diameter equal to or smaller than the valley diameter of the screw.

　本発明の製造方法によれば、筒状部の外径をねじの山径と谷径との間の外径に形成しておき、ねじ加工成形時に一山目のねじの上縁より上方に位置する部分を、ねじの谷径と同じか、それより小さい外径に成形加工することにより、キャップを再度シールする際に、キャップを被せて、キャップ内側のねじ条の最下端がボトル缶のねじ始まり部と次の山部との間の谷部までに案内されるまでの間の抵抗を小さくすることができる。
　また、ねじ成形加工前の筒状部をねじ山径と谷径との間の外径に形成していることから、加工時の塑性変形量は小さいものとなる。なお、筒状部の外径はねじ山径と谷径との間に設定されていればよく、必ずしも中間径でなくてもよい。According to the manufacturing method of the present invention, the outer diameter of the cylindrical portion is formed to be the outer diameter between the peak diameter and the valley diameter of the screw, and the thread is formed above the upper edge of the first thread during thread forming. When re-sealing the cap by molding the positioned portion to an outer diameter equal to or smaller than the screw valley diameter, the cap is put on and the lower end of the thread inside the cap is the bottle can It is possible to reduce the resistance until it is guided to the valley between the screw start and the next peak.
In addition, since the cylindrical portion before the thread forming process is formed to have an outer diameter between the thread diameter and the valley diameter, the amount of plastic deformation at the time of processing is small. The outer diameter of the cylindrical portion may be set between the screw thread diameter and the valley diameter, and may not necessarily be the intermediate diameter.

　本発明のねじ付きボトル缶の製造装置は、有底筒状体の開口部を縮径して肩部を形成するとともに、この肩部よりも上方に、ねじの山径と谷径との間の外径の筒状部と、該筒状部の上端から開口端部に向けて漸次縮径するテーパ部とを形成してなる中間成形体の前記筒状部に、ねじ成形加工を施す装置であって、前記筒状部の内周面に当接される内駒と、外周面に当接される外駒とにより、前記筒状部を挟み込み、該内駒及び該外駒を前記中間成形体の軸心回りに回転することにより、該筒状部にねじを形成する構成とされており、前記内駒及び前記外駒は、前記筒状部にねじを形成するためのねじ形成用凸部及びねじ形成用凹部が螺旋状に、かつ互いに対応する形状でそれぞれ形成されているとともに、前記外駒は、前記筒状部に形成されるねじの一山目の上側に配置されるねじ形成用凸部に連続して、該ねじ形成用凸部と同径か、それより大径の外周リフォーム部が設けられていることを特徴とする。The apparatus for manufacturing a threaded bottle can according to the present invention reduces the diameter of the opening of the bottomed cylindrical body to form a shoulder, and between the peak diameter and the valley diameter of the screw above the shoulder. A device for subjecting the above-mentioned cylindrical portion of an intermediate formed body, which is formed by forming a cylindrical portion with an outer diameter of the above and a tapered portion gradually reducing the diameter from the upper end of the cylindrical portion to the open end, The cylindrical portion is sandwiched between an inner piece that is in contact with the inner peripheral surface of the cylindrical portion and an outer piece that is in contact with the outer peripheral surface, and the inner piece and the outer piece are placed in the middle The cylindrical portion is configured to form a screw by rotating around the axial center of the molded body, and the inner and outer pieces are used to form a screw for forming the screw in the cylindrical portion. The convex portion and the screw forming concave portion are respectively formed in a spiral shape corresponding to each other, and the outer piece is formed in the cylindrical portion. An outer peripheral reforming portion having the same diameter as or larger than the screw forming convex portion is provided continuously to the screw forming convex portion disposed on the upper side of the first ridge of the screw. Do.

　本発明のボトル缶は、本発明の製造方法によって製造されたボトル缶である。
　また、本発明のボトル缶は、開口端に形成されるカール部の下方のテーパ部の下縁からねじの一山目の上縁に至る部分の最大外径が、前記ねじの一山目に隣接する谷部のねじ谷径と同じかそれよりも小さい外径に形成されているとよい。The bottle can of the present invention is a bottle can produced by the production method of the present invention.
Further, in the bottle can of the present invention, the maximum outer diameter of the portion from the lower edge of the tapered portion below the curled portion formed at the open end to the upper edge of the first ridge of the screw is the first ridge of the screw The outer diameter may be equal to or smaller than the threading diameter of the adjacent valley.

　本発明によれば、テーパ部の下縁からねじの一山目の上縁までの部分が、ねじの谷径より大きくなることが抑制されるので、キャップを再度シールする際に、キャップを被せて、キャップ内側のねじ条の最下端がボトル缶のねじ始まり部と次の山部との間の谷部に案内されるまでの間の抵抗を小さくすることができ、再度のシール操作を容易にすることができる。また、ねじ成形加工時の塑性変形量も小さく、一山目のねじにおいても成形時の材料流れの拘束が少ないので、内面塗装への損傷も抑制することができる。According to the present invention, since the portion from the lower edge of the tapered portion to the upper edge of the first ridge of the screw is prevented from becoming larger than the valley diameter of the screw, the cap is covered when the cap is resealed. Therefore, the resistance between the lower end of the inner thread of the cap being guided to the valley between the screw start and the next peak of the bottle can can be reduced and the re-sealing operation is facilitated. Can be In addition, since the amount of plastic deformation at the time of thread forming is small, and the restriction of the material flow at the time of forming is small even in the first thread, damage to the inner surface coating can be suppressed.

本発明の一実施形態において製造途中の中間成形体を示す筒状部付近の正面図である。It is a front view of the cylindrical part vicinity which shows the intermediate | middle molded object in the middle of manufacture in one Embodiment of this invention.図１のボトル缶の中間成形体の成形工程を（ａ）～（ｄ）の順に示す要部の断面図である。FIG. 2 is a cross-sectional view of the main part, showing in order of (a) to (d) the step of forming the intermediate formed body of the bottle can of FIG. 1;開口部を拡径するパンチを示す断面図である。It is sectional drawing which shows the punch which diameter-expands an opening part.開口部を縮径するダイネッキング用成形ツールを示す断面図である。It is sectional drawing which shows the shaping | molding tool for die necking which diameter-reduces an opening part.図１のボトル缶の中間成形体にねじ成形加工を施している状態を示しており、（ａ）が内駒及び外駒をボトル缶の内外に配置した状態を示すねじ始まり部よりも手前の部分に相当する位置の縦断面図、（ｂ）は内駒及び外駒でボトル缶を挟み込んだねじ成形加工中の状態を示す（ａ）と同じ位置の縦断面図である。It shows a state in which a thread forming process is applied to the intermediate formed body of the bottle can of FIG. 1, and (a) shows a state in which the inner piece and the outer piece are arranged inside and outside the bottle can (B) is a longitudinal cross-sectional view at the same position as (a) showing a state during thread forming processing in which a bottle can is sandwiched between an inner piece and an outer piece.一実施形態のボトル缶を示す口金部付近の正面図である。It is a front view of the nozzle | cap part vicinity which shows the bottle can of one Embodiment.一実施形態のボトル缶とキャップとの関係を示す断面図であり、左半分がボトル缶にキャップを螺着した状態、右半分が螺着前でボトル缶にキャップを被せた状態をそれぞれ示している。It is sectional drawing which shows the relationship between the bottle can and cap of one Embodiment, The state which screwed the cap on the left half in the bottle can and the right half has shown the state which covered the cap on the bottle can before screwing, respectively. There is.従来のボトル缶とキャップとの関係を示す図７同様の断面図である。It is sectional drawing like FIG. 7 which shows the relationship between the conventional bottle can and cap.

　以下、本発明の一実施形態について説明する。
　ボトル缶１は、アルミニウム又はアルミニウム合金の薄板金属からなり、有底円筒状の缶胴部（図示略）に、図６に示すように、上方に向けて漸次縮径する肩部２が形成され、その肩部２の上端に小径の首部３が形成され、この首部３の上端に口金部４が形成され、その口金部４の外周にねじ５が形成され、ねじ５より下方にキャップのスカート端部を固定する顎部６が形成され、ねじ５より上方にカール部７が形成されたものである。Hereinafter, an embodiment of the present invention will be described.
The bottle can 1 is made of thin sheet metal of aluminum or aluminum alloy, and as shown in FIG. 6, ashoulder portion 2 whose diameter is gradually reduced upward is formed on a bottomed cylindrical can body (not shown). Theneck portion 3 having a small diameter is formed at the upper end of theshoulder portion 2, thecap 4 is formed at the upper end of theneck 3, thescrew 5 is formed on the outer periphery of the cap 4A jaw 6 for fixing the end is formed, and acurl 7 is formed above thescrew 5.

　このボトル缶１を製造するには、アルミニウム合金等の薄板を絞り加工及びしごき加工（ＤＩ成形）により成形した有底円筒体の開口部を縮径して肩部２を形成し、その後、肩部２よりも上方部分にねじ成形のための拡径した筒状部１１を形成する。
　図２により具体的に説明する。同図（ａ）に示すように、有底円筒体の開口部を縮径して肩部２を形成するとともに、肩部２より上方に筒状の縮径部１７を形成する。この縮径加工はいわゆるダイネッキング加工であり、径の異なる成形ツールを順次使用しながら加工することにより、開口部を徐々に縮径して、図２（ａ）に示す肩部２及び縮径部１７を形成する。In order to manufacture this bottle can 1, the diameter of the opening of the bottomed cylindrical body formed by drawing and ironing (DI molding) of a thin plate such as aluminum alloy is reduced to form theshoulder 2, and then the shoulder The diameter-increasedcylindrical portion 11 for thread formation is formed in the upper portion of theportion 2.
This will be specifically described with reference to FIG. As shown to the figure (a), while diameter-reducing the opening part of a bottomed cylindrical body and forming theshoulder part 2, the cylindrical diameter-reducedpart 17 is formed above theshoulder part 2. As shown in FIG. The diameter reducing process is a so-called die necking process, in which the diameter of the opening is gradually reduced by working while using forming tools having different diameters sequentially, and the diameter of theshoulder 2 and the diameter reduced as shown in FIG. Theportion 17 is formed.

　そして、同図（ｂ）に示すように、この縮径部１７について、その下端部を除き肩部２の上端より若干上方位置から再度拡径し、大径部１８とする。この大径部１８の加工を行う装置は、図３に示すように、ワーク保持部（図示略）に保持された有底円筒体Ｗの開口部（縮径部１７）に缶軸方向に沿って挿入される拡径パンチ５１を備えている。そして、この拡径パンチ５１が有底円筒体Ｗの縮径部１７に挿入されることにより大径部１８が形成され、この大径部１８の加工により、縮径部１７の下端部で拡径加工されなかった部分が首部３となる。And as shown to the figure (b), it diameter-reduces this diameter-reducedpart 17 again from a slightly upper position from the upper end of theshoulder part 2 except the lower end part, and let it be thelarge diameter part 18. The apparatus for processing thelarge diameter portion 18 is, as shown in FIG. 3, along the can axis direction at the opening (diameter reducing portion 17) of the bottomed cylindrical body W held by the workpiece holding portion (not shown). It has an enlargeddiameter punch 51 to be inserted. Then, the enlargeddiameter punch 51 is inserted into the reduceddiameter portion 17 of the bottomed cylindrical body W to form thelarge diameter portion 18, and the processing of thelarge diameter portion 18 causes the enlargedlower end portion 17 to expand. The part which was not diameter processed becomes theneck 3.

　次に、図２（ｃ）に示すように、大径部１８の下端部を除き、この下端部より上方部分を再度縮径することにより、小径部１９を形成する。この加工は、いわゆるダイネッキング加工であり、その成形ツールは、図４に示すように、ワーク保持部（図示略）に保持された有底円筒体Ｗの開口部（大径部１８）に缶軸方向に沿って挿入される内側ダイ５２と、その外側に配置される外側ダイ５３とを備えている。内側ダイ５２の外径は加工前の有底円筒体Ｗの開口部（大径部１８）の内径よりも小さく、縮径後の外径に形成され、外側ダイ５３の内周面は、加工前の有底円筒体Ｗの開口部（大径部１８）を受け入れる内径のガイド面５４、その開口部を縮径する絞り加工のためのテーパ面５５、内側ダイ５２の外周面との間で縮径した開口部を挿入する隙間を形成する小径面５６が先端から順次形成されている。そして、有底円筒体Ｗの開口部（大径部１８）を外側ダイ５３のガイド面５４に沿って圧入することにより、テーパ面５５に倣うように縮径され、開口端部が内側ダイ５２の外周面５２ａと外側ダイ５３の小径面５６との間に挿入され、小径部１９に加工される。前述の図２（ａ）に示す加工も、この図４に示すものと径は異なるが、同様の構造の複数種の内側ダイと外側ダイとの組み合わせのものが用いられる。
　この小径部１９の加工により、小径部１９の下方で加工されなかった部分が拡径部１５となる。この場合、小径部１９は、首部３よりも大きい外径に形成され、後述するねじ５の谷径と山径との中間の外径に形成される。Next, as shown in FIG. 2C, except for the lower end portion of thelarge diameter portion 18, thediameter reduction portion 19 is formed by reducing the diameter of the portion above the lower end portion again. This process is a so-called die-necking process, and its forming tool cans the opening (large diameter portion 18) of the bottomed cylindrical body W held by the work holding portion (not shown) as shown in FIG. It has aninner die 52 inserted along the axial direction and anouter die 53 arranged on the outside thereof. The outer diameter of theinner die 52 is smaller than the inner diameter of the opening (large diameter portion 18) of the bottomed cylindrical body W before processing, and the outer diameter after diameter reduction is formed, and the inner peripheral surface of theouter die 53 is processed Between theguide surface 54 of the inner diameter which receives the opening (large diameter part 18) of the front bottomed cylindrical body W, thetapered surface 55 for drawing which reduces the opening, and the outer peripheral surface of the inner die 52 Asmall diameter surface 56 for forming a gap into which the diameter-reduced opening is inserted is sequentially formed from the tip. Then, the opening (large diameter portion 18) of the bottomed cylindrical body W is press-fitted along theguide surface 54 of theouter die 53 to reduce the diameter so as to follow the taperedsurface 55, and the open end is theinner die 52. Is inserted between the outerperipheral surface 52 a and thesmall diameter surface 56 of theouter die 53 and processed into thesmall diameter portion 19. The processing shown in FIG. 2 (a) described above is also different in diameter from that shown in FIG. 4, but a combination of a plurality of inner dies and an outer die having a similar structure is used.
By processing thesmall diameter portion 19, a portion not processed below thesmall diameter portion 19 becomes anenlarged diameter portion 15. In this case, thesmall diameter portion 19 is formed to have an outer diameter larger than that of theneck portion 3 and is formed to have an outer diameter intermediate between the valley diameter and the peak diameter of thescrew 5 described later.

　次に、同図（ｄ）に示すように、小径部１９の上半分程度を上端に向かって徐々に縮径し、その縮径した開口端部１３と、これに連なるテーパ部１４とを形成する。この加工も図４と同様のダイネッキング加工のための成形ツールが用いられる。この開口端部１３とテーパ部１４の加工により、その下方で加工されなかった部分が筒状部１１となる。これにより中間成形体１２が形成される。なお、この筒状部１１の厚さは０．２５～０．４ｍｍに形成される。
そして、この中間成形体１２において、筒状部１１にねじ５を成形した後、開口端部１３をさらに縮径し、その縮径した部分にカール部７を成形することにより、ボトル缶１が製造される。Next, as shown in FIG. 6D, the diameter of the upper half of thesmall diameter portion 19 is gradually reduced toward the upper end, and the diameter-reducedopening end portion 13 and the taperedportion 14 connected thereto are formed. Do. Also in this processing, a forming tool for die-necking processing similar to that of FIG. 4 is used. By processing the openingend 13 and thetaper portion 14, a portion which is not processed below is thecylindrical portion 11. Thereby, the intermediate formedbody 12 is formed. The thickness of thecylindrical portion 11 is 0.25 to 0.4 mm.
Then, in the intermediate moldedbody 12, after forming thescrew 5 in thecylindrical portion 11, the diameter of theopen end portion 13 is further reduced, and the curledportion 7 is formed in the reduced diameter portion. Manufactured.

　この製造工程において、中間成形体１２は、図１に示したように、開口端部１３が上端からカール部７を成形するために必要な寸法分をストレート状に形成され、その開口端部１３の下端から下方に向けて漸次拡径するテーパ部１４が形成され、このテーパ部１４の下端に筒状部１１が形成されている。この筒状部１１は、下端部を除く大部分がストレートの円筒状に形成され、筒状部１１の下端部は、その上部よりも外径の大きい拡径部１５とされ、その拡径部１５の下端に、縮径された首部３、首部３の下端から拡径する肩部２が連続して形成された形状とされている。In this manufacturing process, as shown in FIG. 1, the intermediate moldedbody 12 is formed into a straight shape having dimensions necessary for forming the curledportion 7 from the upper end of theopen end portion 13. A taperedportion 14 whose diameter gradually increases from the lower end of thelower portion 14 is formed, and thecylindrical portion 11 is formed at the lower end of the taperedportion 14. Thecylindrical portion 11 is formed in a cylindrical shape, most of which is straight except for the lower end portion, and the lower end portion of thecylindrical portion 11 is anenlarged diameter portion 15 having an outer diameter larger than that of the upper portion. Aneck 3 reduced in diameter and ashoulder 2 expanded in diameter from the lower end of theneck 3 are continuously formed at the lower end of thehead 15.

　この場合、開口端部１３の外径Ｄ１は、成形すべきねじ谷径Ｄ２よりも小さく、また、筒状部１１の外径Ｄ３は、その下端部の拡径部１５を除き、ねじ山径Ｄ４とねじ谷径Ｄ２との中間の径に設定される。例えば、ねじ山径Ｄ４が３７ｍｍで、ねじ谷径Ｄ２が３６．３ｍｍで、ねじの一山目と二山目の間隔が２．５ｍｍ～４．５ｍｍである場合、筒状部１１の拡径部１５を除く外径Ｄ３は３６．５ｍｍ～３６．８ｍｍに設定される。また、これら筒状部１１と開口端部１３との間を連絡するテーパ部１４は、缶軸方向に対して２０°～４０°の傾斜角θで、缶軸方向に沿う長さＨが２．６～４．０ｍｍに設定される。In this case, the outer diameter D1 of the openingend 13 is smaller than the thread valley diameter D2 to be formed, and the outer diameter D3 of thecylindrical portion 11 is the thread diameter except for theenlarged diameter portion 15 at the lower end thereof. The diameter is set to an intermediate diameter between D4 and thread thread diameter D2. For example, when the thread diameter D4 is 37 mm, the thread valley diameter D2 is 36.3 mm, and the distance between the first and second threads of the screw is 2.5 mm to 4.5 mm, the diameter of thecylindrical portion 11 is increased. The outer diameter D3 excluding theportion 15 is set to 36.5 mm to 36.8 mm. Further, the taperedportion 14 connecting thecylindrical portion 11 and the openingend portion 13 has a length H along the can axis direction of 2 at an inclination angle θ of 20 ° to 40 ° with respect to the can axis direction. It is set to 6 to 4.0 mm.

　次に、この中間成形体１２に対してねじ５を成形するためのねじ付きボトル缶の製造装置１００について説明すると、製造装置１００は、中間成形体１２の筒状部１１の内周面に当接される内駒２１と、外周面に当接される外駒２２とを有している。これら内駒２１及び外駒２２は、図１及び図５に示すように、その外周面にねじ５を形成するためのねじ形成用凸部２３，２４及びねじ形成用凹部２５，２６が螺旋状に、かつ互いに対応する形状でそれぞれに形成されており、これら内駒２１及び外駒２２がそれぞれ半径方向に移動することにより、互いの凹凸部間に中間成形体１２の筒状部１１を挟み込み、中間成形体１２の軸心回りに回転することにより、筒状部１１にねじ５が形成される構成である。なお、このとき、ねじ５の下方に配置される顎部６も同時に加工される。
　また、外駒２２には、筒状部１１に形成されるねじ５の一山目の上側に配置されるねじ形成用凸部２４に連続して、そのねじ形成用凸部２４と同径か、それより大径の外周リフォーム部２７が設けられている。そして、内駒２１は、ねじ５の一山目の上側に配置されるねじ形成用凹部２５に連続する部分が、そのねじ形成用凹部２５と同径か、それより小径に形成されており、外駒２２の外周リフォーム部２７によって筒状部１１及びテーパ部１４を成形する際の逃げ部２８となっている。Next, themanufacturing apparatus 100 for a threaded bottle can for molding thescrew 5 with respect to the intermediate moldedbody 12 will be described. Themanufacturing apparatus 100 is in contact with the inner peripheral surface of thecylindrical portion 11 of the intermediate moldedbody 12. It has aninner piece 21 to be in contact and anouter piece 22 to be in contact with the outer peripheral surface. As shown in FIG. 1 and FIG. 5, in theinner piece 21 and theouter piece 22, screw formingconvex parts 23 and 24 and screw formingconcave parts 25 and 26 for forming thescrew 5 on the outer peripheral surface are helical. And theinner pieces 21 and theouter pieces 22 respectively move in the radial direction, thereby sandwiching thecylindrical portion 11 of the intermediate moldedbody 12 between the uneven portions. Thescrew 5 is formed on thecylindrical portion 11 by rotating around the axis of the intermediate moldedbody 12. At this time, thejaws 6 disposed below thescrew 5 are also processed at the same time.
In addition, theouter piece 22 may have the same diameter as the screw formingconvex portion 24 continuously to the screw formingconvex portion 24 disposed on the upper side of the first ridge of thescrew 5 formed in thecylindrical portion 11 The outer peripheral reformingportion 27 having a larger diameter than that is provided. Theinner piece 21 is formed to have the same diameter as that of thescrew forming recess 25 or a smaller diameter than that of thescrew forming recess 25 which is continuous with thescrew forming recess 25 disposed on the upper side of the first ridge of thescrew 5. The outerperiphery reforming portion 27 of theouter piece 22 serves as arelief portion 28 when thetubular portion 11 and the taperedportion 14 are formed.

　この内駒２１と外駒２２とによるねじ成形について図５により詳述する。
　予め、ねじ５の形状について説明しておくと、ねじ５は、図６に示すように、その山部３１の高さが所定の寸法になるまでの間に高さが漸次大きくなる不完全ねじ部３２が存在し、ねじ始まり部３３は、その不完全ねじ部３２において、山部３１の高さの半分程度の高さを有する部分をいうものとする。また、山部３１の高さは、山部３１とその山部３１に隣接する谷部３４との間の半径方向寸法の最大値の平均値をいい、ねじ山径Ｄ４は山部３１の外径、ねじ谷径Ｄ２は谷部３４の外径をいう。
　なお、ねじ成形加工は、必ずしもねじ始まり部３３から始まるとは限らず、任意の位置から加工される。The thread formation by theinner piece 21 and theouter piece 22 will be described in detail with reference to FIG.
Before explaining the shape of thescrew 5, as shown in FIG. 6, thescrew 5 is an incomplete screw whose height gradually increases while the height of thepeak portion 31 becomes a predetermined dimension. Theportion 32 is present, and thescrew start portion 33 is a portion having a height about half the height of thepeak portion 31 in theincomplete thread portion 32. Further, the height of theridge 31 is an average value of the maximum values of the radial dimension between theridge 31 and thevalley 34 adjacent to theridge 31, and thethread diameter D 4 is outside theridge 31. The diameter and the thread valley diameter D2 refer to the outer diameter of thevalley portion 34.
The thread forming process does not necessarily start from thescrew start portion 33, and is processed from an arbitrary position.

　図５は、ねじ成形加工後にねじ始まり部３３よりも手前の位置の縦断面図を示しており、ねじの一山目が一周分近く巻回して二山目になる手前の位置の断面図である。
　図５（ａ）は、中間成形体１２の筒状部１１の内側に内駒２１が挿入され、筒状部１１の半径方向外方に外駒２２が配置され、相互に対峙した状態を示し、（ｂ）が内駒２１と外駒２２とが接近して筒状部１１をテーパ部１４の途中から挟み込んだ状態を示している。また、便宜上、図５（ａ）においては内駒と外駒の半分ずつを正面視したもの、残り半分を外形線のみ示したが、（ｂ）においては内駒、外駒とも外形線のみ示した。
　また、この図５の断面において、一点鎖線の位置は、ねじの一山目（一周分近く巻回して二山目になる手前のねじ山）がＡ、その上の谷部の位置をＢとする。FIG. 5 shows a longitudinal cross-sectional view of a position before thescrew start portion 33 after thread forming processing, and is a cross-sectional view of a position before the first ridge of the screw is wound for one round to become the second ridge. is there.
FIG. 5 (a) shows a state in which theinner piece 21 is inserted inside thecylindrical portion 11 of the intermediate moldedbody 12 and theouter pieces 22 are disposed radially outward of thecylindrical portion 11, facing each other. (B) shows a state in which theinner piece 21 and theouter piece 22 come close to each other and sandwich thecylindrical portion 11 from the middle of the taperedportion 14. Also, for convenience, in FIG. 5 (a), a half of each of the inner and outer pieces is viewed from the front, and only the outline is shown on the other half. However, in (b), only the outlines of the inner and outer pieces are shown. .
Further, in the cross section of FIG. 5, the position of the alternate long and short dash line is such that the first peak of the screw (a screw thread in front of the second round by winding for one round) is A, and the position of the upper valley portion is B Do.

　図５（ａ）に示すように、筒状部１１とテーパ部１４との間の屈曲部１６は、外周リフォーム部２７の位置に配置されている。この図５（ａ）に示す状態から両駒２１，２２が接近して、筒状部１１を挟み込んでねじ成形加工がなされると、図５（ｂ）に示すように、筒状部１１に形成されるねじの一山目の上縁からテーパ部１４の一部に至る部分が外周リフォーム部２７により縮径加工されることにより、その外径が、ねじの谷径Ｄ２と同じか、それより小さく加工され、筒状部１１及びテーパ部１４の最大外径はねじ谷径Ｄ２と同じか、それより小さくなる。As shown to Fig.5 (a), the bendingpart 16 between thecylindrical part 11 and thetaper part 14 is arrange | positioned in the position of the outerperiphery reforming part 27. As shown in FIG. When both thepieces 21 and 22 approach from the state shown in FIG. 5A and thecylindrical portion 11 is sandwiched and screw-formed, thecylindrical portion 11 is formed as shown in FIG. 5B. The portion from the upper edge of the first ridge of the formed screw to a portion of the taperedportion 14 is reduced in diameter by the outer peripheral reformingportion 27 so that the outer diameter is equal to the valley diameter D2 of the screw or The smaller outer diameter of thecylindrical portion 11 and the taperedportion 14 is equal to or smaller than the thread valley diameter D2.

　このようにしてねじ成形加工した後、開口端部１３に対してカーリング加工してカール部７を形成することにより、ボトル缶１が製造される。
　このボトル缶１に被せられるキャップ４１は、円形の天板部４２と円筒状のスカート部４３とを有しており、ボトル缶１の口金部４に被せた後、キャッピングロールによってキャップ４１のスカート部４３を口金部４のねじ５に倣うように成形することにより、スカート部４３にねじ条４４が形成されるとともに口金部４に螺着した状態となり、スカート部４３の下端部４５を顎部６に巻き込むことにより、図７の左半分に示したようにキャップ４１とボトル缶１とは螺着状態に固定される。このようにしてキャップ４１が口金部４のねじ５に螺着されるので、キャップ４１のねじ条４４の内径は口金部４のねじ谷径Ｄ２に合わせられることになる。なお、このキャップに関しては、各部位を示す際に、ねじ形成前とねじ形成後とで同じ符号を用いて説明する。After the screw forming process as described above, theopen end 13 is curled to form the curledportion 7, whereby the bottle can 1 is manufactured.
Thecap 41 put on the bottle can 1 has a circulartop plate portion 42 and acylindrical skirt portion 43, and after putting it on themouthpiece 4 of the bottle can 1, the skirt of thecap 41 is covered by a capping roll. By forming theportion 43 so as to follow thescrew 5 of themouthpiece 4, thethread 44 is formed on theskirt 43 and is screwed to themouthpiece 4, and thelower end 45 of theskirt 43 is jawd As shown in the left half of FIG. 7, thecap 41 and the bottle can 1 are fixed in a screw-on state by being wound around 6. Thus, since thecap 41 is screwed to thescrew 5 of themouthpiece 4, the inner diameter of thescrew thread 44 of thecap 41 is matched with the thread valley diameter D2 of themouthpiece 4. In addition, regarding this cap, when showing each part, it demonstrates using the same code | symbol before screw formation and after screw formation.

　次に、キャップ４１を開栓した後、再度シールする場合について説明する。
　図７の左半分に示した螺着状態からキャップ４１を緩めるように回転すると、スカート部４３に形成されていたスリット４６の部分から下端部４５とその上部との間が破断して、下端部が帯状に顎部６に残され、その上部を口金部４から外すことができる。Next, a case where thecap 41 is opened and then sealed again will be described.
When thecap 41 is rotated so as to loosen thescrew 41 from the screwed state shown in the left half of FIG. 7, the space between thelower end 45 and the upper part is broken from the portion of theslit 46 formed in theskirt 43 Is left on thejaws 6 in the form of a band, and the upper portion thereof can be removed from themouthpiece 4.

　次に、その外したキャップ４１を再度シールするため口金部４に被せると、図７の右半分に示すように、キャップ４１の内周面のねじ条４４の最下端が口金部４のテーパ部１４上を滑りながら下降してねじ５の一山目の上面に当接する。このとき、キャップ４１を右に回転させることにより、ねじ条４４の最下端を一山目の上面を伝って、その下方の谷部３４の入り口まで案内する。Next, when thecap 41 removed is put again on thecap 4 to seal it again, as shown in the right half of FIG. 7, the lowermost end of thethread 44 on the inner peripheral surface of thecap 41 is the tapered portion of thecap 4 The slidinggear 14 is lowered while sliding on the upper surface of the first ridge of thescrew 5. At this time, by rotating thecap 41 to the right, the lower end of thescrew thread 44 is guided along the upper surface of the first peak to the entrance of thevalley 34 below.

　前述したように、ねじ５の一山目の上方のテーパ部１４は、その最大外径がねじ谷径Ｄ２と同じか、それより小さい寸法に形成されているので、キャップ４１の内周面のねじ条４４は、筒状部１１及びテーパ部１４による抵抗を受けることが少なく、一山目の上面までスムーズに到達し、その後、一山目の下方の谷部３４の入り口まで簡単に案内することができる。そして、キャップ４１を回転することにより、その谷部３４にねじ条４４の最下端を進入させてねじ込むことができる。As described above, since the taperedportion 14 above the first ridge of thescrew 5 is formed to have the same maximum diameter as or smaller than the thread valley diameter D2, the inner peripheral surface of thecap 41 is Thescrew thread 44 is less likely to receive resistance by thecylindrical portion 11 and thetaper portion 14 and smoothly reaches the top surface of the first peak, and then easily guided to the entrance of thevalley portion 34 below the first peak. Can. Then, by rotating thecap 41, the lower end of thescrew thread 44 can be inserted into thevalley 34 and screwed.

　因みに、従来のボトル缶について図８により説明すると、従来のボトル缶では、一山目の上方のテーパ部６１にねじ谷径Ｄ２よりも大きい部分６２が残るので、キャップ４１を再度シールする際に、そのねじ谷径Ｄ２より大きい部分６２へのキャップ４１のねじ条４４の接触度合が大きく、ねじを閉め込むときの抵抗が大きいため、再度のシール操作がし難いものとなっていた。
　日本電産シンポ株式会社製デジタルトルクメータにボトル缶を保持した状態でキャップを再度シールする際のリシールトルク（キャップを口金部に被せてシール操作する際にキャップの天面のライナーがボトル缶のカール部天面に接触するまでに生じた抵抗値）を測定したところ、本発明の実施形態のボトル缶では０．２Ｎ・ｃｍであったが、従来のボトル缶では８．７Ｎ・ｃｍであった。
　このように、本発明の製造方法により製造されたボトル缶１は、ねじ５の一山目の上縁より上方に位置する部分（筒状部１１及びテーパ部１４）がねじ谷径Ｄ２と同じか、ねじ谷径Ｄ２よりも小さく形成されているので、再度のシール操作を容易にすることができる。Incidentally, to explain the conventional bottle can with reference to FIG. 8, in the conventional bottle can, since theportion 62 larger than the thread trough diameter D2 remains in the taperedportion 61 above the first peak, when thecap 41 is sealed again. Since the degree of contact of thescrew thread 44 of thecap 41 with theportion 62 larger than the screw thread diameter D2 is large and the resistance when the screw is tightened is large, it is difficult to perform the sealing operation again.
The resealing torque when the cap is re-sealed while holding the bottle can in the digital torque meter manufactured by Nidec-Shimpo Co., Ltd. (The cap on the top of the cap is the bottle can when the cap is put on the cap and sealing operation is performed It was 0.2N cm in the bottle can of the embodiment of the present invention when the resistance value generated until it came in contact with the top of the curled part was 0.2N cm in the embodiment of the present invention, but 8.7 N cm in the conventional bottle can The
Thus, in the bottle can 1 manufactured by the manufacturing method of the present invention, the portion (thecylindrical portion 11 and the tapered portion 14) located above the upper edge of the first ridge of thescrew 5 is the same as the thread valley diameter D2. Or, since it is formed smaller than the thread trough diameter D2, it is possible to facilitate the sealing operation again.

　なお、本発明は前記実施形態の構成のものに限定されるものではなく、細部構成においては、本発明の趣旨を逸脱しない範囲において種々の変更を加えることが可能である。
　筒状部の外径としてねじ山径と谷径との中間の径に設定したが、ねじ山径と同じ外径あるいは谷径と同じ外径に設定してもよく、これらねじ山径と谷径との間の外径に設定されていればよい。The present invention is not limited to the configuration of the above-described embodiment, and various modifications can be made in the detailed configuration without departing from the spirit of the present invention.
The outer diameter of the tubular portion is set to an intermediate diameter between the thread diameter and the valley diameter, but the outer diameter may be the same as the thread diameter or the outer diameter may be the same as the valley diameter. It may be set to an outer diameter between the diameter and the diameter.

　本発明は、コーヒー飲料等の各種飲料を充填し、キャップのリシールが容易なねじ付きボトル缶の製造方法及び製造装置として適用できる。Industrial Applicability The present invention can be applied as a method and an apparatus for producing a screw can having various beverages such as coffee drinks and easy to reseal a cap.

　１　ボトル缶
　２　肩部
　３　首部
　４　口金部
　５　ねじ
　６　顎部
　７　カール部
　１１　筒状部
　１２　中間成形体
　１３　開口端部
　１４　テーパ部
　１５　拡径部
　１６　屈曲部
　２１　内駒
　２２　外駒
　２３，２４　ねじ形成用凸部
　２５，２６　ねじ形成用凹部
　２７　外周リフォーム部
　２８　逃げ部
　３１　山部
　３２　不完全ねじ部
　３３　ねじ始まり部
　３４　谷部
　４１　キャップ
　４２　天板部
　４３　スカート部
　４４　ねじ条
　４５　下端部
　４６　スリット
　１００　ねじ付きボトル缶の製造装置

 DESCRIPTION OF SYMBOLS 1 bottle can 2shoulder part 3neck part 4cap part 5screw 6jaw part 7 curledpart 11cylindrical part 12 intermediate moldedbody 13 openingend part 14taper part 15enlarged diameter part 16bent part 21inner piece 22outer piece 23, 24 Screw formingconvex parts 25 and 26 Screw formingconcave parts 27 outer peripheral reformingpart 28relief part 31peak part 32incomplete screw part 33screw starting part 34valley part 41cap 42top plate part 43skirt part 44thread 45lower end part 46 Equipment for manufacturing slit cans with 100 screw bottles

Claims (4)

1. 　有底筒状体の開口部を縮径して肩部を形成するとともに、この肩部よりも上方に、ねじの山径と谷径との間の外径の筒状部と、該筒状部の上端から開口端部に向けて漸次縮径するテーパ部とを形成しておき、前記筒状部にねじ成形加工するとともに、該筒状部に形成されるねじの一山目の上縁から前記テーパ部の一部に至る部分の外径を、ねじの谷径と同じか、それより小さい径に加工することを特徴とするねじ付きボトル缶の製造方法。The diameter of the opening of the bottomed tubular member is reduced to form a shoulder, and a tubular portion having an outer diameter between the peak diameter and the valley diameter of the screw and above the shoulder, and the tubular Forming a tapered portion whose diameter gradually decreases from the upper end of the portion toward the opening end, and screw-forming the cylindrical portion, and the upper edge of the first ridge of the screw formed in the cylindrical portion And processing the outer diameter of the portion from the tip to a part of the tapered portion to a diameter equal to or smaller than the valley diameter of the screw.
2. 　有底筒状体の開口部を縮径して肩部を形成するとともに、この肩部よりも上方に、ねじの山径と谷径との間の外径の筒状部と、該筒状部の上端から開口端部に向けて漸次縮径するテーパ部とを形成してなる中間成形体の前記筒状部に、ねじ成形加工を施す装置であって、前記筒状部の内周面に当接される内駒と、外周面に当接される外駒とにより、前記筒状部を挟み込み、該内駒及び該外駒を前記中間成形体の軸心回りに回転することにより、該筒状部にねじを形成する構成とされており、前記内駒及び前記外駒は、前記筒状部にねじを形成するためのねじ形成用凸部及びねじ形成用凹部が螺旋状に、かつ互いに対応する形状でそれぞれ形成されているとともに、前記外駒は、前記筒状部に形成されるねじの一山目の上側に配置されるねじ形成用凸部に連続して、該ねじ形成用凸部と同径か、それより大径の外周リフォーム部が設けられていることを特徴とするねじ付きボトル缶の製造装置。The diameter of the opening of the bottomed tubular member is reduced to form a shoulder, and a tubular portion having an outer diameter between the peak diameter and the valley diameter of the screw and above the shoulder, and the tubular A device for subjecting the cylindrical portion of an intermediate molded body having a tapered portion whose diameter gradually decreases from the upper end of the portion toward the opening end portion by thread forming, the inner peripheral surface of the cylindrical portion By sandwiching the tubular portion with the inner piece in contact with the outer piece and the outer piece in contact with the outer peripheral surface, and rotating the inner piece and the outer piece around the axial center of the intermediate formed body, The cylindrical portion is formed with a screw, and the inner piece and the outer piece have a screw forming convex portion for forming a screw in the cylindrical portion and a screw forming concave portion in a spiral shape. And the outer pieces are formed in shapes corresponding to each other, and the outer piece is a screw disposed on the upper side of the first ridge of the screw formed in the cylindrical portion Continuously to forming convex portion, the screw-forming convex part and either the same diameter, threaded bottle can manufacturing apparatus characterized by the outer peripheral remodeling of larger diameter than is provided.
3. 　請求項１に記載の製造方法によって製造されたねじ付きボトル缶。A threaded bottle can manufactured by the manufacturing method according to claim 1.
4. 　開口端に形成されるカール部の下方のテーパ部の下縁からねじの一山目の上縁に至る部分の最大外径が、前記ねじの一山目に隣接する谷部のねじ谷径と同じかそれよりも小さい外径に形成されていることを特徴とするねじ付きボトル缶。
    
   
    The maximum outer diameter of the portion from the lower edge of the lower taper of the curled portion formed at the open end to the upper edge of the first peak of the screw is the thread valley diameter of the valley adjacent to the first peak of the screw A threaded bottle can, characterized in that it is formed to the same or smaller outer diameter.
   
   
   

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