JPH044135B2

JPH044135B2 -

Info

Publication number: JPH044135B2
Application number: JP56059443A
Authority: JP
Priority date: 1981-04-20
Filing date: 1981-04-20
Publication date: 1992-01-27
Also published as: JPS57174218A

Description

[Detailed description of the invention]

［産業上の利用分野］本発明は、プラスチツク・ボトル等のブロー成
形品の製造方法とその装置に関する。［従来の技術］ボトル等の樹脂成形品の製造方法の一つとし
て、ブロー成形加工がある。この方法では、第１
図ａに示すように、左右に開閉する１対の合せ型
１，２からなる金型が用いられる。合せ型１，２
のパーテイング面にはそれぞれ成形用のキヤビテ
イ４，５が設けられている。このキヤビテイ４，
５の上部において、合せ型１，２は成形素材とな
るパリソン（加熱されて軟化状態となつている樹
脂管）６を、型閉時でも完全に潰すことなく管断
面を維持させるようにガイド溝７を有し、下部に
はパリソン６を絞つて溶着させるとともにパリソ
ンを切断するための尖鋭な喰い切り部８を有して
いる。ボトルを製造する際には、第１図ａに示すよう
に、合せ型１，２を型開状態にしておいた後、合
せ型１，２間にパリソン６を挿入し、その後、同
図ｂに示すように合せ型を型閉めする。パリソン
６の下部は喰い切り部８で絞られて溶着して底９
が形成される。また、パリソン６の上部はガイド
溝７によつて細く絞り込まれて容器口１０が形成
される。ガイド溝７にはねじ型１１が形成されて
いるため、パリソン６の絞り込みに伴つてパリソ
ン６の外周にはキヤツプ用ねじ１２が形成され
る。ガイド溝７によつて絞り込まれたパリソン部
分は管体を維持していることから、そこを通して
パリソン６内にブローイングエアーを吹き込み、
同図ｃで示すように、キヤビテイ４，５内に位置
しているパリソン部分をキヤビテイ４，５の壁面
に達するまで膨らましてボトルの成形を行なう。
次に、合せ型１，２を開き、容器口１０の上縁で
パリソン６を切断するとともに、底９の外面にぶ
ら下がつているパリソン残材１３を取り去る。そ
れによつて、同図ｄで示すようなボトル１４が得
られる。［発明が解決しようとする課題］しかし、このような従来の金型３では、金型閉
鎖時に、パリソン６の被喰い切り部が引き伸ばさ
れて喰い切られるため、第２図で示すように、ボ
トル底９の溶着部１５には中央の窪み１６が発生
し、肉薄となつて溶着部１５の耐圧、落下強度の
機械的強度が低下する欠点がある。また、杷手付ボトルにおいても、従来の金型を
使う限り、杷手の溶着部（被喰い切り部）断面が
同様に薄肉となつて機械的強度が低くなる。一方、溶着部を厚くするために、金型の閉鎖速
度を遅くしたり、金型閉鎖時の喰い切り部分間に
若干のクリアランスを設けること等が行なわれて
いるが、これらの方策を講じても、溶着部（被喰
い切り部）が厚くなるだけで、依然として窪みは
残り、効果的な解決方法ではない。［課題を解決するための手段］このような課題を解決するために、本発明の製
造方法及びその装置は、ブロー成形用金型の喰い
切り部の外側にパリソンの喰い切り動作前から喰
い切り時に亙つてパリソンを圧縮する弾力を利用
した圧縮装置を備えたブロー成形用金型によつて
成形を行ない、成形時に圧縮装置によつて溶着部
（被喰い切り部）の内壁を盛り上げた状態で喰い
切りを行なつた後、ブローイングエアの吹き込
み、型開きを行なうようにして、溶着部内面に肉
盛り上げ部を形成し、外面は通常のようにほぼ平
面に形成されるようにするものである。［作用］本発明の製造方法および装置によれば、ブロー
イング成形用金型の喰い切り部の外側にパリソン
の喰い切り動作前から喰い切り時に亘つてパリソ
ンを圧縮する圧縮装置を備えたブロー成形用金型
によつて成形を行なうので、成形時に金型喰い切
り部の喰い切り作動前に圧縮装置によつて金型の
キヤビテイ側にパリソン合せ部の一部が押し込ま
れ、溶着部（被喰い切り部）内壁を盛り上げた状
態で喰い切りが行われるようになる。〔実施例〕以下、実施例により本発明を説明する。第３図ａ〜ｅは本発明の一実施例に係る製造装
置の金型を用いてボトルを成形する工程を示す断
面図であり、第４図は整形したボトルの底を示す
断面図である。第５図は金型に設けた圧縮装置の
圧縮機構を示す断面図、第６，７図は夫々第５図
の左側面図及び平面図である。さらに、第８図ａ
〜ｃは第３図の圧縮装置の動作状態を示す拡大断
面図である。本発明装置の金型３は従来構造の１対の合せ型
１，２の喰い切り部８の下部に、第３図及び第８
図ａ〜ｃで示すような圧縮機構１７，１８を設け
るようにしてなる。これら１対の圧縮機構１７，
１８は喰い切り部８の下方に突出するパリソン６
を圧縮する圧縮装置１９を構成している。圧縮機
構１７，１８は共に同一構造となり、対称に配設
される。そこで、第５図〜第７図によつて、一方の圧縮
機構１８の構造について説明する。合せ型２の喰
い切り部８は下方のパーテイング面には圧縮板ガ
イド孔２０が設けられ、この圧縮板ガイド孔２０
には圧縮板２１が出入自在に嵌合されている。圧
縮板はパリソンの幅よりも広くなつている。前記圧縮板ガイド孔２０の奥底と連通する２本
の支柱ガイド孔２２が、合せ型２を貫通する状態
で穿たれている。この支柱ガイド孔２０の両端部
にはブツシユ２３が嵌合され、且つＯ−リング２
４が内装されている。そして、ブツシユ２３およ
びＯ−リング２４を貫通して支柱ガイド孔２２に
は、管状の支柱２５が軸方向に往復動可能に挿入
されている。同支柱２５の左端（第５図）は圧縮
板２１の内部に嵌入する状態で螺合されている。
また、圧縮板２１内には冷水路が設けられ、この
冷水路を介して２本の支柱２５は連通状態となつ
ている。また、支柱ガイド孔２２から突出した支
柱２５の右端には、冷却水の給排水を行なうパイ
プを繋ぐ管状のジヨイント２７が螺合されてい
る。このジヨイント２７はその外径が支柱ガイド
孔２２の直径よりも大きくなつていて、支柱２５
が支持ガイド孔２２から抜け出ないようになつて
いる。また、圧縮板ガイド孔２０の奥底と圧縮板
２１との間において、支柱２５の周囲部には圧縮
コイルばね２８が挿嵌され、常に圧縮板２１を圧
縮板ガイド孔２０から抜け出る第５図の左方向に
付勢している。したがつて、圧縮板２１の圧縮面
２９は合せ型２のパーテイング面よりも通常突出
している。この突出長さは支柱２５の多端に螺合されてい
るジヨイント２７を回動操作することによつて容
易に調整できる。圧縮板２１の圧縮面２９の上縁
２９ａは、第６図に示すように、キヤビテイ５の
喰い切部８の縁（刃）と一定の間隔を有するよう
に延在するとともに、第５図に示すように、パリ
ソンをキヤビテイ５側に押し上げる働きをする斜
面（押出面）３０を有している。この斜面３０は
たとえば５〜10°の傾きとなつている。つぎに、第３図ａ〜ｅを用いて本実施例装置に
よるボトルの製造方法について説明する。同図ａ
に示すように、金型３の合せ型１，２を開いた
後、上方からパリソン６を挿入し、パリソン６の
下端が圧縮装置１９に達した時点で停止させる。
つぎに、同図ｂで示すように、型閉めを進め、パ
リソン６を金型３内に保持する。圧縮板２１の圧
縮面２９は、圧縮コイルばね２８によつて合せ型
１，２のパーテイング面よりも突出していること
から、型閉時に圧縮面２９が最初にパリソン６の
周面に接触し、合せ型１，２の進行に伴なつて圧
縮面２９でパリソン６を絞ることになる。この段
階では第３図ｂおよび第８図ａで示すように、喰
い切り部８の刃が絞り込まれてパリソンの曲線を
描く部分にわずかに接触するだけであり、パリソ
ン６の絞りによる合わせ部３１は、圧縮装置１９
の一対の圧縮板２１により押え付けられている。その後、さらに金型３の閉鎖動作を続けると、
金型３の閉鎖力は圧縮コイルばねよりも強いた
め、第８図ｂのように、喰い切り部８は相互に前
進し、拡開しているパリソン部分を互いに挾持す
るようになる。この際、圧縮板２１の上部は傾斜
した押出面３０を有していることから、圧縮板２
１間のパリソン合せ部３１の樹脂は上方（キヤビ
テイ４，５側方向）に一部押し出されて盛り上が
るようになる。また、パリソン６は圧縮板２１に
よつて圧着されていることから、下方への移動も
停止されている。このため、喰い切り部８の挾み
込み動作に伴つて、この喰い切り部８間のパリソ
ン部分（樹脂部分）は上方に洩れ出て盛り上がり
を続ける。また、金型３の閉鎖動作は、最終的に
は第３図ｃおよび第８図ｃで示すように、１対の
喰い切り部８の当接で終る。この金型閉鎖動作の
最終段階では、圧縮板２１間のパリソン合せ部３
１はさらに押し潰される。この結果、パリソン６
の溶着部１５の継ぎ目の内側には小高い盛り上が
り部３２が形成される（第４図参照）。一方、金型閉鎖によつて、パリソン６の上部に
は第３図ｃのようにボトルの容器口１０が形成さ
れる。容器口１０の外周には合せ型１，２の構造
からしてねじ１２がパリソン６の絞り込みによつ
て同時に形成される。その後、第３図ｄに示すように、パリソン６の
上部からブローイングエアーを吹き込むことによ
つて、ボトル成形を行なうとともに、型開きおよ
びパリソン６の容器口１０の切断によつて、第３
図ｅで示すようなボトル１４を製造する。なお、この実施例において、一方の支柱２５の
ジヨイント２７端から冷却水を支柱２５に送り込
むことによつて、圧縮板２１を冷却し、それによ
つて、圧縮板２１に接触したパリソン６の温度を
降下させることができる。この結果、パリトン合
せ部３１の冷却固化を促進することができるた
め、樹脂（パリソン）の下方への移行を停止で
き、盛り上がり部３２の形成を容易とすることが
できる。このような金型によつて製造したボトルは、そ
の溶着部が厚くなるため、従来品に比べて下記の
表に示すように機械的強度が向上する。 [Industrial Field of Application] The present invention relates to a method and apparatus for manufacturing blow-molded products such as plastic bottles. [Prior Art] Blow molding is one of the methods for manufacturing resin molded products such as bottles. In this method, the first
As shown in Figure a, a mold consisting of a pair of mating molds 1 and 2 that open and close left and right is used. Combined type 1, 2
Molding cavities 4 and 5 are provided on each parting surface. This cavity 4,
In the upper part of the mold 5, the mating molds 1 and 2 have guide grooves so that the parison (resin pipe that has been heated and softened) 6, which is the molding material, maintains the pipe cross section without being completely crushed even when the mold is closed. 7, and the lower part thereof has a sharp cutout 8 for squeezing and welding the parison 6 and cutting the parison. When manufacturing a bottle, as shown in Figure 1a, after opening the mating molds 1 and 2, the parison 6 is inserted between the mating molds 1 and 2, and then the parison 6 is inserted between the mating molds 1 and 2. Close the mating mold as shown. The lower part of the parison 6 is squeezed by the cutout 8 and welded to form the bottom 9.
is formed. Further, the upper part of the parison 6 is narrowed down by the guide groove 7 to form a container opening 10. Since a thread type 11 is formed in the guide groove 7, a cap screw 12 is formed on the outer periphery of the parison 6 as the parison 6 is narrowed down. Since the part of the parison narrowed by the guide groove 7 maintains a pipe body, blowing air is blown into the parison 6 through it.
As shown in Figure c, the parison portions located within the cavities 4 and 5 are inflated until they reach the walls of the cavities 4 and 5 to form a bottle.
Next, the combined molds 1 and 2 are opened, and the parison 6 is cut at the upper edge of the container mouth 10, and the parison remaining material 13 hanging on the outer surface of the bottom 9 is removed. As a result, a bottle 14 as shown in d of the figure is obtained. [Problems to be Solved by the Invention] However, in such a conventional mold 3, when the mold is closed, the portion to be cut of the parison 6 is stretched and cut off, so that as shown in FIG. The welded part 15 of the bottle bottom 9 has a depression 16 in the center, which becomes thinner and has the disadvantage that the mechanical strength of the welded part 15 in terms of pressure resistance and drop strength is reduced. In addition, as long as a conventional mold is used for a bottle with a bar, the cross section of the welded part (cut part) of the bar will similarly become thin and the mechanical strength will be low. On the other hand, in order to thicken the welded area, methods such as slowing down the closing speed of the mold and creating a slight clearance between the cut-out parts when the mold is closed have been taken. However, this is not an effective solution because the welded part (the part to be cut away) only becomes thicker, but the dent still remains. [Means for Solving the Problems] In order to solve the above-mentioned problems, the manufacturing method and the device thereof of the present invention provide a method for manufacturing a blow molding die, in which a cutout is formed on the outside of the cutout portion of the blow molding die before the cutout operation of the parison. Molding is sometimes carried out using a blow molding mold equipped with a compression device that utilizes elasticity to compress the parison, and the inner wall of the welded part (cut part) is raised by the compression device during molding. After cutting, blowing air is blown and the mold is opened to form a raised part on the inner surface of the welded part, so that the outer surface is formed almost flat as usual. . [Function] According to the manufacturing method and apparatus of the present invention, a mold for blow molding is provided with a compression device on the outside of the cut-out portion of the blow molding mold for compressing the parison from before the cut-off operation to during the cut-off operation of the parison. Since forming is performed using a mold, a part of the parison mating part is pushed into the cavity side of the mold by a compression device before the part of the mold is cut out during molding, and the weld part (the part to be cut) is pressed into the cavity side of the mold. Part) Cutting is now performed with the inner wall raised. [Example] The present invention will be explained below with reference to Examples. 3A to 3E are cross-sectional views showing the process of molding a bottle using a mold of a manufacturing apparatus according to an embodiment of the present invention, and FIG. 4 is a cross-sectional view showing the bottom of a shaped bottle. . FIG. 5 is a sectional view showing the compression mechanism of the compression device provided in the mold, and FIGS. 6 and 7 are a left side view and a plan view of FIG. 5, respectively. Furthermore, Figure 8a
-c are enlarged sectional views showing the operating state of the compression device of FIG. 3; The mold 3 of the device of the present invention is placed at the lower part of the cut-out portion 8 of the pair of mating molds 1 and 2 of the conventional structure, as shown in FIGS. 3 and 8.
Compression mechanisms 17 and 18 as shown in Figures a to c are provided. These pair of compression mechanisms 17,
18 is a parison 6 protruding below the cutout part 8
It constitutes a compression device 19 that compresses. Both compression mechanisms 17 and 18 have the same structure and are arranged symmetrically. Therefore, the structure of one compression mechanism 18 will be explained with reference to FIGS. 5 to 7. A compression plate guide hole 20 is provided in the lower parting surface of the cutout part 8 of the mating mold 2, and this compression plate guide hole 20
A compression plate 21 is fitted in and out in a freely removable manner. The compression plate is wider than the parison. Two pillar guide holes 22 communicating with the deep bottom of the compression plate guide hole 20 are bored through the mating mold 2. A bush 23 is fitted into both ends of this support guide hole 20, and an O-ring 2
4 are installed inside. A tubular support 25 is inserted through the bush 23 and O-ring 24 into the support guide hole 22 so as to be able to reciprocate in the axial direction. The left end (FIG. 5) of the support column 25 is screwed into the compression plate 21 so as to fit into the interior thereof.
Further, a cold water channel is provided in the compression plate 21, and the two pillars 25 are in communication via this cold water channel. Furthermore, a tubular joint 27 that connects a pipe for supplying and discharging cooling water is screwed to the right end of the column 25 protruding from the column guide hole 22. The outer diameter of this joint 27 is larger than the diameter of the column guide hole 22, and the column 25
The support guide hole 22 is designed so that it does not escape from the support guide hole 22. Further, a compression coil spring 28 is fitted around the support column 25 between the deep bottom of the compression plate guide hole 20 and the compression plate 21, and the compression plate 21 is always pulled out from the compression plate guide hole 20 as shown in FIG. It is biased to the left. Therefore, the compression surface 29 of the compression plate 21 normally protrudes beyond the parting surface of the mating die 2. This protrusion length can be easily adjusted by rotating a joint 27 that is threaded onto the other end of the support column 25. As shown in FIG. 6, the upper edge 29a of the compression surface 29 of the compression plate 21 extends at a constant distance from the edge (blade) of the cutout 8 of the cavity 5. As shown, it has a slope (extrusion surface) 30 that functions to push the parison up toward the cavity 5 side. This slope 30 has an inclination of, for example, 5 to 10 degrees. Next, a method for manufacturing a bottle using the apparatus of this embodiment will be explained using FIGS. 3a to 3e. Figure a
As shown in FIG. 3, after opening the combined molds 1 and 2 of the mold 3, the parison 6 is inserted from above, and stopped when the lower end of the parison 6 reaches the compression device 19.
Next, as shown in FIG. 3B, the mold is closed and the parison 6 is held within the mold 3. Since the compression surface 29 of the compression plate 21 protrudes beyond the parting surfaces of the mating molds 1 and 2 due to the compression coil spring 28, the compression surface 29 first contacts the circumferential surface of the parison 6 when the mold is closed. As the mating dies 1 and 2 advance, the parison 6 is compressed by the compression surface 29. At this stage, as shown in FIG. 3b and FIG. 8a, the blade of the cut-off part 8 is squeezed and only slightly contacts the curved part of the parison, and the joining part 31 of the parison 6 due to drawing is is the compression device 19
It is pressed down by a pair of compression plates 21 . After that, if you continue the closing operation of mold 3,
Since the closing force of the mold 3 is stronger than that of the compression coil spring, the cutouts 8 move forward relative to each other and clamp the expanding parison portions together, as shown in FIG. 8b. At this time, since the upper part of the compression plate 21 has an inclined extrusion surface 30, the compression plate 21
A portion of the resin in the parison joining portion 31 between the holes 1 and 1 is pushed out upward (toward the sides of the cavities 4 and 5) and rises. Moreover, since the parison 6 is compressed by the compression plate 21, its downward movement is also stopped. Therefore, as the cut-out portions 8 are inserted, the parison portions (resin portions) between the cut-out portions 8 continue to leak upward and bulge. Furthermore, the closing operation of the mold 3 ultimately ends with the pair of cutouts 8 coming into contact, as shown in FIGS. 3c and 8c. In the final stage of this mold closing operation, the parison joining part 3 between the compression plates 21
1 is further crushed. As a result, parison 6
A slightly elevated portion 32 is formed inside the seam of the welded portion 15 (see FIG. 4). On the other hand, by closing the mold, a bottle mouth 10 is formed in the upper part of the parison 6 as shown in FIG. 3c. Due to the structure of the mating molds 1 and 2, a thread 12 is simultaneously formed on the outer periphery of the container mouth 10 by narrowing the parison 6. Thereafter, as shown in FIG. 3d, the bottle is formed by blowing air from the upper part of the parison 6, and the third bottle is formed by opening the mold and cutting the container mouth 10 of the parison 6.
A bottle 14 as shown in Figure e is manufactured. In this embodiment, the compression plate 21 is cooled by sending cooling water into the column 25 from the end of the joint 27 of one of the columns 25, thereby reducing the temperature of the parison 6 in contact with the compression plate 21. It can be lowered. As a result, cooling and solidification of the parison matching portion 31 can be promoted, so that downward migration of the resin (parison) can be stopped, and the formation of the raised portion 32 can be facilitated. Bottles manufactured using such molds have thicker welded parts, and therefore have improved mechanical strength compared to conventional products, as shown in the table below.

【表】また、この実施例の金型刃、従来の金型の喰い
切り部を加工するだけでよいことから、金型の作
成が簡単である。また、圧縮装置の構造も動力源
等を必要とせず簡素であることから、製作費も従
来品に較べてあまち高くはならない。また、この実施例の金型の取付構造および操作
方法は従来品と同等であることから、操作が簡単
である。なお、本発明は前記実施例に限定されず、例え
ば支柱のジヨイントおよび圧縮板との接続構造は
他の構造でもよい。また、ジヨイント内へは気体
を流入させて冷却を行なうようにしてもよい。また、この金型構造はブローピン打込み成形、
エアー吹き込み針を使用した成形方法等、成形形
態を問わず適用できる。第９〜１２図は、本発明装置の他の実施例を示
し、上記金型構造における圧縮装置を、第９図〜
第１２図ａ，ｃで示すように、把手付ボトルの内
側被喰い切り部分の溶着を行なう場所に設けたも
のである。この場合は、第９図および第１０図に
示すように、金型３の合せ型１，２によつてパリ
ソン６を成形して第９図に示す把手３３を有する
把手付ボトル３４を製造する。圧縮装置１９は、
把手付ボトル３４の容器部３５と把手３３とを区
画する空間部３６に対応する金型部分に配設され
る。第１１図ａ〜ｅは第９図のＡ−Ａ線に沿う断
面における成形動作を示す断面図、第１２図ａ，
ｂは第９図のＢ−Ｂ線に沿う断面にをける成形動
作を示す断面図である。第１１図ａに示すよう
に、型開き状態の合せ型１，２間にパリソン６を
挿入した後、第１１図ｂ〜ｄおよび第１２図ａに
示すように型閉を行なう。その後、ブローイングエアーを吹き込んで、パ
リソン６を合せ型１，２のキヤビテイ４，５の内
壁面までに拡開させる。その後、型開きを行なうことになり、第１１図
ｅ６９および第１２図ｂに示すように、断面が管
状の把手３３および容器部が形成される。また、
把手３３と容器部３５間の圧縮残材３７およびパ
リソン残材１３は除去され、かつ図示はしない
が、容器口で切断されて把手付ボトル３４が製造
される。この実施例においては、把手３３の内側溶着部
１５および容器溶着部１５の継ぎ目部分はともに
圧縮装置によつて盛り上がり部３２が形作され
る。この結果、把手等の継ぎ目の機械的強度も高
くなる。なお、この実施例では圧縮板２１には押
出し面３０を設けていないが、設けてもよい。［発明の効果］以上のように、本発明の方法と装置によれば、
成形時に溶着部を厚くできるため、成形品の機械
強度が従来に較べて高くなる。このため、成形品
への被収容物充填時の充填圧によつて溶着部が破
損することが防がれる。また、成形品の輸送時に
おける落下事故によつても、成形品が溶着部で破
損するようなことはなくなる。さらに、本発明の
成形品によれば、長期保存の内容物の蒸発、分解
によつて成形品内の圧力が上昇しても、溶着部の
耐圧が従来品よりも高いことから、内容物の保存
期間が長くなる。また、本発明の装置は従来の金型に圧縮装置を
取り付けるだけでよいので製作費も安価であると
ともに、金型の使用方法も従来品と変わりない。
さらに、圧縮面の喰い切り部との相対位置の調
整、圧縮装置の弾圧力を加減することにより、容
器盛り上がり量を制御することも可能となる。したがつて、本発明による方法及び装置は、操
作性もよい等多くの効果を奏するものである。[Table] Furthermore, since it is only necessary to process the mold blade of this embodiment and the cut-out portion of a conventional mold, the mold can be easily created. Furthermore, since the structure of the compression device is simple and does not require a power source, the manufacturing cost is not much higher than that of conventional products. Furthermore, since the mold mounting structure and operating method of this embodiment are the same as those of the conventional product, the operation is easy. It should be noted that the present invention is not limited to the above-mentioned embodiment, and for example, the joint of the support and the connection structure with the compression plate may be other structures. Further, cooling may be performed by allowing gas to flow into the joint. In addition, this mold structure also includes blow pin injection molding,
It can be applied regardless of the molding form, such as a molding method using an air blowing needle. 9 to 12 show other embodiments of the device of the present invention, and the compression device in the mold structure described above is shown in FIGS. 9 to 12.
As shown in FIGS. 12a and 12c, this is provided at the location where the cut-out portion of the inner side of the bottle with handle is to be welded. In this case, as shown in FIGS. 9 and 10, the parison 6 is molded by the combined molds 1 and 2 of the mold 3 to produce a bottle with handle 34 having the handle 33 shown in FIG. . The compression device 19 is
It is disposed in a mold portion corresponding to a space 36 that partitions the container portion 35 and handle 33 of the bottle 34 with a handle. 11a to 11e are cross-sectional views showing the forming operation in a cross section along line A-A in FIG. 9, and FIGS.
b is a sectional view showing the forming operation taken along the line BB in FIG. 9; As shown in FIG. 11a, the parison 6 is inserted between the mating molds 1 and 2 in the opened state, and then the molds are closed as shown in FIGS. 11b to 12d and 12a. Thereafter, blowing air is blown to expand the parison 6 to the inner wall surfaces of the cavities 4 and 5 of the mating molds 1 and 2. Thereafter, the mold is opened, and as shown in FIG. 11e69 and FIG. 12b, a handle 33 and a container portion having a tubular cross section are formed. Also,
The compressed residual material 37 and the parison residual material 13 between the handle 33 and the container part 35 are removed and, although not shown, are cut at the container mouth to produce a bottle with a handle 34. In this embodiment, a raised portion 32 is formed at both the joint portion of the inner welded portion 15 of the handle 33 and the welded portion 15 of the container by a compression device. As a result, the mechanical strength of joints such as handles is also increased. Note that although the compression plate 21 is not provided with the extrusion surface 30 in this embodiment, it may be provided. [Effects of the Invention] As described above, according to the method and apparatus of the present invention,
Since the welded portion can be made thicker during molding, the mechanical strength of the molded product is higher than that of conventional molded products. Therefore, the welded portion is prevented from being damaged by the filling pressure when filling the molded product with the object to be accommodated. Furthermore, even if the molded product is dropped during transportation, the molded product will not be damaged at the welded portion. Furthermore, according to the molded product of the present invention, even if the pressure inside the molded product increases due to evaporation or decomposition of the contents during long-term storage, the pressure resistance of the welded part is higher than that of conventional products, so the contents Storage period will be longer. Furthermore, since the device of the present invention only requires attaching a compression device to a conventional mold, the manufacturing cost is low, and the method of using the mold is no different from that of conventional products.
Further, by adjusting the relative position of the compression surface with the cut-out portion and adjusting the elastic force of the compression device, it is also possible to control the amount of swelling of the container. Therefore, the method and apparatus according to the present invention have many advantages such as good operability.

[Brief explanation of drawings]

第１図はａ〜ｄは従来のブロー成形用金型によ
るブロー成形方法を示す各工程での断面図、第２
図は同じく従来のブロー成形品の溶着部を示す断
面図である。第３図ａ〜ｅは本発明のブロー成形
品製造装置によるブロー成形方法を示す各工程で
の断面図、第４図は本発明のブロー成形品の溶着
部を示す断面図、第５図は本発明装置の金型にお
ける圧縮装置の圧縮機構を示す要部断面図、第６
図は第５図の左側面図、第７図は同じく一部を断
面とした第５図の平面図である。第８図ａ〜ｃは
同じく第５図の圧縮装置の動作を示す要部拡大断
面図である。第９図〜第１２図ａ，ｂは本発明の
他の実施例である把手付ボトルの製造装置を示す
図であつて、第９図および第１０図はパリソンと
成形品および金型との関係を示す概念図、第１１
図ａ〜ｅは第９図のＡ−Ａ線における圧縮装置の
動作状態を示す断面図、第１２図ａ，ｂは第９図
のＢ−Ｂ線における圧縮装置の動作状態を示す断
面図、である。１，２……合せ型、３……金型、６……パリソ
ン、８……喰い切り部、１４……ボトル、１５…
…溶着部、１７，１８……圧縮機構、１９……圧
縮装置、２１……圧縮板、２９……圧縮面、３０
……斜面（押出面）、３２……盛り上がり部、３
３……把手、３４……把手付きボトル。 In Fig. 1, a to d are cross-sectional views at each step showing a blow molding method using a conventional blow molding die;
The figure is also a sectional view showing a welded part of a conventional blow molded product. 3a to 3e are cross-sectional views showing each step of the blow molding method using the blow molded product manufacturing apparatus of the present invention, FIG. 4 is a cross-sectional view showing the welded part of the blow molded product of the present invention, and FIG. A sectional view of the main parts showing the compression mechanism of the compression device in the mold of the device of the present invention, No. 6
The figure is a left side view of FIG. 5, and FIG. 7 is a plan view of FIG. 5, with a portion of the same partially in section. 8a to 8c are enlarged sectional views of essential parts showing the operation of the compression device of FIG. 5. 9 to 12a and 12b are diagrams showing an apparatus for producing a bottle with a handle, which is another embodiment of the present invention, and FIGS. 9 and 10 show the connection between a parison, a molded product, and a mold. Conceptual diagram showing relationships, 11th
Figures a to e are cross-sectional views showing the operating state of the compression device along the line A-A in Figure 9, and Figures 12a and b are cross-sectional views showing the operating state of the compression device along the line B-B in Figure 9. It is. 1, 2... Matching mold, 3... Mold, 6... Parison, 8... Cutout section, 14... Bottle, 15...
... Welded part, 17, 18 ... Compression mechanism, 19 ... Compression device, 21 ... Compression plate, 29 ... Compression surface, 30
... Slope (extrusion surface), 32 ... Swelling part, 3
3...handle, 34...bottle with handle.

Claims

[Claims] 1. After the parison is inserted between a pair of mating molds each having a cavity and the molds begin to close, the container The parison located on the outside is pressed from both sides through elasticity, the parison is squeezed on this compressed surface, and a part of the parison material is moved inside the cavity from the cutout, thereby building up the inside of the welded part of the parison. 1. A method for manufacturing a blow molded product, which comprises: after forming a part, closing the mold against an elastic pressing force against the parison, blowing blowing air, and opening the mold. 2. A compression device equipped with compression plates that elastically presses the parison from both sides as the mating molds advance is installed at the outer side of the parison cutting part of a mold consisting of a pair of mating molds each having a cavity. and compressing the parison by the compression device immediately before the cut-out portions of the mating molds abut each other,
By moving a part of the compressed parison material from the cut-out part to the inside of the cavity, a raised part is formed inside the drawn and welded part of the parison, and then
A blow molded product manufacturing apparatus characterized in that the mold is closed and blow molding is performed against the elastic force of the compression plate.