JP3544706B2

JP3544706B2 - Biaxial stretch blow molded container

Info

Publication number: JP3544706B2
Application number: JP15163094A
Authority: JP
Inventors: 英幸小林
Original assignee: Nissei ASB Machine Co Ltd
Current assignee: Nissei ASB Machine Co Ltd
Priority date: 1994-06-09
Filing date: 1994-06-09
Publication date: 2004-07-21
Anticipated expiration: 2019-07-21
Also published as: JPH07329158A

Description

【０００１】
【産業上の利用分野】
本発明は、二軸延伸ブロー成形容器に関し、特に、二軸延伸ブロー成形容器の壁面構造に関する。
【０００２】
【従来の技術】
周知のように、例えば、ポリエチレンテレフタレート（ＰＥＴ）を用いて二軸延伸ブロー成形された容器（以下、ボトルという）は、耐ガスバリヤ性、透明度、強靱性、衛生面等に多くの利点を有する。
【０００３】
ところで、二軸延伸ブロー成形によって得られたボトルの一つに、耐熱瓶と称されるものがある。この耐熱瓶は、殺菌のために高温にされたジュース等の内容物を充填することができるボトルである。
【０００４】
しかしながら、このようなボトルでは、高温充填された内容物が冷めると内容物の減容により内部が減圧雰囲気となり、ボトル壁部が減圧変形することがある。このような減容減圧による変形はボトル全体の外観形状の変化を招き、ボトルの商品価値を損うことになる。
【０００５】
そこで、このような減容減圧が起きた場合の対策として、壁部の一部のみを減容減圧による変形を行なわせて、ボトル全体の外観形状の変形を防止する構造が採用されている。
【０００６】
この構造は、減圧パネルと称されるものであって、ボトルの壁部表面にボトル内方に向け窪んだ凹部を複数設けた構造が通常用いられている。これにより、減容減圧が発生した場合に凹部のみを減圧変形させることでボトルの他の部分での形状変化を防止することができる。
【０００７】
一方、上記二軸延伸ブロー成形によって得られるボトルには、デザイン上、一例として長方形の断面形状を有するものがある。なお、この場合の断面は、ボトルの縦方向と直角な方向の断面をいう。
【０００８】
そして、このような長方形断面のボトルに対しても減圧パネルを設けることが行なわれており、正方形断面の場合には４辺全ての壁面に、また長方形断面の場合には撓み変形しやすい長辺の壁面にそれぞれ減圧パネルが形成されている。
【０００９】
この減圧パネルは、一般にボトルの壁部における上下２ヵ所に形成されるようになっている。
【００１０】
また、この種のボトルには、各辺が交差する位置に面取り部が形成されて各辺を連続させたものもある。この面取り部を形成する理由としては、ボトル角部、つまり、壁面をなす各辺の交差する位置の強度を確保することが理由となっている。したがって、このようなボトルの断面形状は八角形とされている。
【００１１】
【発明が解決しようとする課題】
しかしながら、上記した容器のうち、正方形断面の場合には、ほとんど減容減圧時の減圧変形が各辺の壁面で略均等に行われるので外観形状の変化が少ないが、特に、長方形断面のように辺の長さが違うボトルの場合には、短い辺の壁面が膨出して外観形状が変化してしまうことがある。
【００１２】
すなわち、高温内容物充填時には、液圧と壁部の熱変形によって膨出変形し易く、その後の冷却時には、減圧によって壁部はボトル内方へへこみ変形し易い。この場合、幅広壁部の方がへこみ易いので減圧変形部が変形するが、幅狭壁部はなかなかへこみ変形しにくい。したがって、膨出変形してしまうとそのままの状態が保たれてしまうことになる。
【００１３】
そこで、幅狭壁部に横リブを形成したら熱充填時の膨出変形は防止された。しかし、この幅狭壁部では全く減圧変形は見込めないため、他の壁部、とりわけ下方に形成された幅広壁部の役割は大きくなる。
【００１４】
ところで、熱充填温度が予定よりも高く設定された場合や、運搬中の衝撃等による外力、あるいは、消費者による把持時の圧力による変形が、この負担の多い幅広壁部にかかった場合、幅広壁部の減圧変形部以外の面が変形し、自己復帰できなくなることがあるという問題があった。
【００１５】
このような減圧パネル間に位置する壁面の減容減圧時における変形は、特に下側の減圧パネルの上部付近にみられることが多いものであった。
【００１６】
本発明は、前述の問題点に着目してなされたもので、その目的は、内容物の加熱充填時などに壁面が膨出するのを防止すると共に、減容減圧時に減圧パネル以外の壁面が凹んで形状変形するのを防止することのできる二軸延伸ブロー成形容器を提供することにある。
【００１７】
【課題を解決するための手段】
前記目的を達成するため、第１の発明は、
幅広の壁部及び幅狭の壁部の交差部に面取り部を有し、横断面略長方形に成形された壁部の内、前記幅広の壁部の高さ方向略中央位置下側に、減容減圧時の減圧変形部を設けた二軸延伸ブロー成形容器において、
前記幅狭の壁部及びその両隣の面取り部にわたって窪ませたリブを有し、
前記リブの長手方向中央領域のリブ深さがその両端領域のリブ深さよりも浅くされていることを特徴としている。
【００１８】
第２の発明は、第１の発明において、
前記両端領域のリブは、面取り部から幅狭の壁部に延長されていることを特徴としている。
【００１９】
第３の発明は、
幅広の壁部及び幅狭の壁部の交差部に面取り部を有し、横断面略長方形に成形された壁部の内、前記幅広の壁部の高さ方向略中央位置下側に、減容減圧時に減圧変形する凹部を有する減圧変形部を設けた二軸延伸ブロー成形容器において、
前記幅狭の壁部及びその両隣の面取り部にわたって窪ませたリブを有し、
前記リブの少なくとも長手方向中央領域のリブ深さが、前記減圧変形部の凹部の深さよりも浅くされていることを特徴としている。
【００２０】
【作用】
前記構成の第１の発明にあっては、内容物の加熱充填時に、前記幅狭の壁部及びその両隣の面取り部にわたって窪ませたリブによって幅狭の壁部が補強された状態となっているため、内容物の重量や変形した壁部から加わる圧力、さらには熱変形等が加わったとしても、幅狭の壁部下部側の膨出変形は防止されることとなる。
【００２１】
特に、リブの長手方向中央領域のリブ深さが両端部のリブ深さよりも浅くされることによって、幅狭の壁部において、一定の減圧値以上の圧力が加わった場合に、その圧力をリブの変形により吸収することが可能となる。
【００２２】
したがって、壁部の減圧変形力による変形を、減圧変形部内に止めて、商品価値を損わないようになっている。
【００２３】
第２の発明にあっては、中央領域のリブに比し深くなっている両端領域のリブが面取り部から幅狭の壁部に延長されることにより、この両端領域のリブが幅狭の壁部の両側部を補強することとなり、内容物の重量や変形した壁部から加わる圧力、さらには熱変形等が加わったとしても、幅狭の壁部全体が膨出変形するのを確実に防止することができる。
【００２４】
また、内容物の減容減圧時に、一定の減圧値を越えて減圧変形部に減圧変形力が加わった場合であっても、面取り部に変形を生じさせることなく、幅狭の壁部内のリブ部分のみを減圧変形させることができる。
【００２５】
したがって、壁部の内圧や減圧による変形を、幅狭の壁部内に止めて、商品価値を損わないようにしている。
【００２６】
第３の発明にあっては、第１の発明の発明と同様に、幅狭の壁部及びその両隣の面取り部にわたって窪ませたリブによって、内容物の重量や変形した壁部から加わる圧力、さらには熱変形等が加わったとしても、幅狭の壁部全体が膨出変形するのを確実に防止できる。
【００２７】
また、内容物の減容減圧時に、一定の減圧値を越えて減圧変形部に減圧変形力が加わった場合であっても、長手方向中央部領域のリブ深さが減圧変形部の凹部の深さよりも浅くされているため、中央領域のリブが変形して減圧を吸収することができる。
【００２８】
【実施例】
以下、本発明の好適な実施例について、図面を参照して詳細に説明する。
【００２９】
図１〜図３は、本発明の一実施例に係る二軸延伸ブロー成形容器（以下、ボトルという）の断面図である。
【００３０】
この実施例に示されているボトル１０は、たとえばポリエチレンテレフタレート（ＰＥＴ）を用いて、二軸延伸ブロー成形により、上端側の開口部を含むリップ部１２と、このリップ部１２から下方に連なる肩部１４と、下端側の底部１６と、この底部１６から上方に連なるヒール部１８と、このヒール部１８と肩部１４との間に形成された胴部２０とが一体に成形されたものとなっている。
【００３１】
胴部２０は、それぞれ対向位置に配置された一対の幅広の壁部２２および幅狭の壁部２４を有する横断面略長方形に形成されている。この胴部２０には、各幅広の壁部２２および幅狭の壁部２４同士の交差部に面取り部２６が高さ方向にわたって形成されている。この面取り部２６は、幅狭の壁部２４よりも幅狭に形成され、幅広の壁部２２および幅狭の壁部２４の交差部の補強をなすようになっている。すなわち、胴部２０は、幅広の壁部２２および幅狭の壁部２４の各交差部に面取り部２６が配置され、しかも面取り部２６が幅狭の壁部２４よりも幅狭となっているため、各壁部２２、２４の交差部４ヵ所が各壁部２２、２４よりも強度の高い面取り部２６によって補強された状態となっている。
【００３２】
また、胴部２０の高さ方向中央位置よりも上方位置に、内方に窪む溝部２８が形成されるようになっている。この溝部２８は、幅広の壁部２２、幅狭の壁部２４および面取り部２６にわたり周方向に連続して設けられるようになっており、この溝部２８を境に、胴部２０が上胴部３０と、下胴部３２とに区分けされるようになっている。このように、溝部２８が、胴部２０上下方向における途中位置に形成されることにより、胴部２０の上下方向途中位置で胴部２０の側圧に対する補強を行うと共に、胴部２０を上胴部３０および下胴部３２の上下方向において小単位に区分けすることにより、胴部２０の座屈変形を防止するようになっている。
【００３３】
さらに、充填された内容物からの液圧を大きく受ける下胴部３２には、幅広の壁部２２に内容物の減容減圧時に減圧変形可能な減圧変形部３４を設けると共に、幅狭の壁部２４に内容物の加熱充填時や幅広の壁部２２把持時の外側への膨らみを防止するリブ３６が設けられるようになっている。
【００３４】
減圧変形部３４は、幅広の壁部２２の下胴部３２中央部分に縦長の略長方形状に形成されており、この減圧変形部３４内には周囲に前記壁部２２の減圧変形部３４を除く外表面（以下、一般面と称す）よりも内方に向かって窪む凹部３８が環状に連続した状態で形成され、この凹部３８に囲まれる中央部分に前記壁部２２の一般面よりも若干内方よりに位置する平面部４０が凹部３８から連続した状態で形成されている。そして、内容物の減容減圧時に、凹部３８の外周縁部分をヒンジ支点として平面部４０が内方に減圧変形し得るようになっている。
【００３５】
また、減圧変形部３４内の上部位置には、横方向にわたる補強溝４２が形成されている。この補強溝４２は、減圧変形部３４の周囲に形成した凹部３８よりも深く内方に向けて窪んだ状態で形成され、補強リブとして機能するもので、減圧変形部３４上部の補強を行い、減圧変形部３４の上部に連なる壁部２２の一般面が減圧変形部３４の減圧変形に伴って変形するのを防止するようにしている。また、補強溝４２は、減圧変形部３４内において、減圧変形部３４の凹部３８上端位置からその上に連なる壁部２２の途中位置まで延設した状態で設けられており、この補強溝４２と溝部２８との間の壁面の間隔が狭くなるようにしている。したがって、補強溝４２と溝部２８との間に補強リブが形成された状態となって、リブ効果が高くなり、より一層、減圧変形部３４の上部に連なる壁部２２の一般面が減圧変形部３４の減圧変形に伴って変形するのを確実に防止することが可能となる。さらに、補強溝４２の底部と減圧変形部３４の上方位置の一般面との間の立上り部４３に、補強段部４５を設け、立上り部４３の補強を行い、凹部３８上端が確実にヒンジ支点となるようにしている。
【００３６】
リブ３６は、幅狭の壁部２４の高さ方向に所定間隔で複数本（本実施例においては５本）、幅方向全域にわたって設けられており、このリブ３６によって、幅狭の壁部２４の補強を行うことにより、内容物の加熱充填時や幅広の壁部２２の把持時における壁部２４の膨出を防止するようにしている。
【００３７】
また、各リブ３６の両端部には、幅狭の壁部２４と面取り部２６とが交差する角部を越えて両隣の面取り部２６にわたって延長された延長部４４が設けられており、このようにリブ３６を両隣の面取り部２６まで延長させることにより、リブ３６の両端部分を、幅狭の壁部２４よりも幅狭で曲げ強度の高い面取り部２６に支持させることができ、より一層、壁部２４の膨出を確実に防止できるようになっている。
【００３８】
さらに、各リブ３６は幅狭の壁部２４内にある長手方向中央領域のリブ３６の深さＤ２が、その両端領域に形成された延長部４４の深さＤ１よりも浅く形成され、減圧変形部３４に一定の減圧値以上の減圧変形力が加わった場合に、延長部４４よりも深さの浅い幅狭の壁部２４におけるリブ３６部分が減圧変形し得るようにして、幅広の壁部２２に設けた減圧変形部３４の上部に連なる壁部２２の一般面の減圧変形を防止するようにしている。
【００３９】
また、幅狭の壁部２４におけるリブ３６部分の深さＤ２は、幅広の壁部２２に設けた減圧変形部３４内の凹部３８の深さＤ３よりも浅く形成され、減圧変形部３４に一定の減圧値以上の減圧変形力が加わった場合に、凹部３８よりも深さの浅い幅狭の壁部２４におけるリブ３６部分が容易に減圧変形し得るようにして、幅広の壁部２２に設けた減圧変形部３４の上部に連なる壁部２２の一般面の減圧変形を防止するようにしている。
【００４０】
さらに、上胴部３０の幅広の壁部２２および幅狭の壁部２４には、それぞれ内容物の減容減圧時に減圧変形し得る減圧変形部４６、４８が設けられている。幅広の壁部２２においては減圧変形部４６は大きく形成され、幅狭の壁部２４においては減圧変形部４８は比較的小さく形成されるようになっている。また、上胴部３０においては、下胴部３２に比べて面積が小さく、幅広の壁部２２および幅狭の壁部２４の強度も高いので、減圧変形部４６、４８は凹部５０、５２および平面部５４、５６のみで構成され、補強溝は設けられておらず、しかも、幅狭の壁部２４にはリブが設けられていない。
【００４１】
本実施例は以上のような構成であるから、内容物を加熱充填する際に、胴部２０に液圧がかかって、胴部２０、特に下胴部３２に膨出方向の圧力がかかった場合であっても、リブ３６によって下胴部３２の幅狭の壁部２４が補強されているため、膨出状態となるのは防止される。特に、リブ３６は、両端部が強度の高い面取り部２６まで延長されて支持された状態となっているため、壁部２４の膨出は確実に防止されることとなる。
【００４２】
また、胴部２０の幅広の壁部２２を把持して内圧が高くなった場合であっても、前記リブ３６の存在により、幅狭の壁部２４の膨出が確実に防止されることとなる。
【００４３】
さらに、加熱充填された内容物が減容減圧した場合であっても、上胴部３０の減圧変形部４６、４８および下胴部３２の幅広の壁部２２に設けた減圧変形部３４が減圧変形して内容物の減容減圧に対応することとなる。
【００４４】
この場合、減圧時の下胴部３２における減圧変形部３４の減圧変形に伴って、減圧変形部３４の上部と連なる壁部２２の一般面が変形を起こしやすいが、幅狭の壁部２４内におけるリブ３６の深さＤ２が両端部に形成された延長部４４の深さＤ１よりも浅く形成され、しかも、幅狭の壁部２４におけるリブ３６部分の深さＤ２が、幅広の壁部２２に設けた減圧変形部３４内の凹部３８の深さＤ３よりも浅く形成されているため、減圧変形部３４に一定の減圧値以上の減圧変形力が加わった場合に、幅狭の壁部２４におけるリブ３６部分が確実に減圧変形して、幅広の壁部２２に設けた減圧変形部３４の上部に連なる壁部２２の一般面の減圧変形を防止することとなる。
【００４５】
また、減圧変形部３４内上部に設けた補強溝４２の補強によって前記一般面の変形がより確実に防止されることとなる。特に、補強溝４２が減圧変形部３４に形成した凹部３８よりも深く内方に窪ませられ、かつ、前述の如く減圧変形部３４上方に延設されることにより、胴部２０に形成した溝部２８と補強溝３４との間の壁部２２の一般面の間隔が狭められて、補強リブとして機能するため、より確実に一般面の変形が防止されることとなる。
【００４６】
本発明は、前記各実施例に限定されるものではなく、本発明の要旨の範囲内において種々の変形実施が可能である。
【００４７】
例えば、前記実施例においては、上胴部にリブを形成していないが、上胴部においてはラベル等が貼付されることが多く、このラベル等の貼付に影響のない面取り部等の部分にリブを形成することは可能である。
【００４８】
また、本実施例においては、幅狭の壁部２４内におけるリブ３６の深さＤ２が両端部に形成された延長部４４の深さＤ１よりも浅く形成され、しかも、幅狭の壁部２４内におけるリブ３６部分の深さＤ２が、幅広の壁部２２に設けた減圧変形部３４内の凹部３８の深さＤ３よりも浅く形成されているが、この深さの関係は、幅狭の壁部内におけるリブ部分と、凹部または延長部との関係のいずれかの関係のみとすることも可能である。
【００４９】
さらに、幅狭の壁部２４内におけるリブ３６部分の深さのまま延長部４４を延長させることも可能である。
【００５０】
【発明の効果】
以上説明したように第１の発明にあっては、内容物の加熱充填時に、前記幅狭の壁部及びその両隣の面取り部にわたって窪ませたリブによって幅狭の壁部が補強された状態となっているため、内容物の重量や変形した壁部から加わる圧力、さらには熱変形等が加わったとしても、幅狭の壁部下部側の膨出変形は防止されるという効果がある。
【００５１】
特に、リブの長手方向中央領域のリブ深さが両端部のリブ深さよりも浅くされることによって、幅狭の壁部において、一定の減圧値以上の圧力が加わった場合に、その圧力をリブの変形により吸収することが可能となる。
【００５２】
したがって、壁部の減圧変形力による変形を、減圧変形部内に止めて、商品価値を損わないようするという効果がある。
【００５３】
第２の発明によれば、中央領域のリブに比し深くなっている両端領域のリブが面取り部から幅狭の壁部に延長されることにより、この両端領域のリブが幅狭の壁部の両側部を補強することとなり、内容物の重量や変形した壁部から加わる圧力、さらには熱変形等が加わったとしても、幅狭の壁部全体が膨出変形するのを確実に防止することができるという効果がある。
【００５４】
また、内容物の減容減圧時に、一定の減圧値を越えて減圧変形部に減圧変形力が加わった場合であっても、面取り部に変形を生じさせることなく、幅狭の壁部内のリブ部分のみを減圧変形させることができるという効果がある。
【００５５】
したがって、壁部の内圧や減圧による変形を、幅狭の壁部内に止めて、商品価値を損わないようするという効果がある。
【００５６】
第３の発明によれば、第１の発明の発明と同様に、幅狭の壁部及びその両隣の面取り部にわたって窪ませたリブによって、内容物の重量や変形した壁部から加わる圧力、さらには熱変形等が加わったとしても、幅狭の壁部全体が膨出変形するのを確実に防止できるという効果がある。
【００５７】
また、内容物の減容減圧時に、一定の減圧値を越えて減圧変形部に減圧変形力が加わった場合であっても、長手方向中央部領域のリブ深さが減圧変形部の凹部の深さよりも浅くされているため、中央領域のリブが変形して減圧を吸収することができるという効果がある。
【図面の簡単な説明】
【図１】本発明の一実施例に係る二軸延伸ブロー成形容器の幅広の壁部側からみた正面図である。
【図２】図１の幅狭の壁部側からみた部分破断正面図である。
【図３】図１のＩＩＩ −ＩＩＩ線に沿う断面図である。
【符号の説明】
１０ボトル
２０胴部
２２幅広の壁部
２４幅狭の壁部
２６面取り部
２８溝部
３０上胴部
３２下胴部
３４減圧変形部
３６リブ
３８凹部
４２補強溝
４４延長部[0001]
[Industrial applications]
The present invention relates to a biaxially stretched blow-molded container, and more particularly, to a wall structure of a biaxially stretched blow-molded container.
[0002]
[Prior art]
As is well known, for example, a container (hereinafter, referred to as a bottle) biaxially stretch-blown using polyethylene terephthalate (PET) has many advantages in terms of gas barrier resistance, transparency, toughness, hygiene, and the like.
[0003]
By the way, one of the bottles obtained by biaxial stretch blow molding is called a heat-resistant bottle. This heat-resistant bottle is a bottle that can be filled with contents such as juice heated for sterilization.
[0004]
However, in such a bottle, when the content charged at a high temperature cools, the inside of the bottle becomes a reduced-pressure atmosphere due to volume reduction of the content, and the bottle wall may be deformed under reduced pressure. Such deformation due to volume reduction and decompression causes a change in the appearance and shape of the entire bottle, which impairs the commercial value of the bottle.
[0005]
Therefore, as a countermeasure against the occurrence of such volume reduction and pressure reduction, a structure is employed in which only a part of the wall is deformed by volume reduction and pressure reduction to prevent deformation of the external shape of the entire bottle.
[0006]
This structure is called a decompression panel, and a structure in which a plurality of concave portions that are depressed toward the inside of the bottle is provided on the surface of the wall of the bottle is generally used. Thus, when the volume reduction and pressure reduction occur, only the concave portion is deformed by pressure reduction, thereby preventing a shape change in other portions of the bottle.
[0007]
On the other hand, some bottles obtained by the biaxial stretch blow molding have a rectangular cross-sectional shape as an example in design. The cross section in this case refers to a cross section in a direction perpendicular to the longitudinal direction of the bottle.
[0008]
A decompression panel is provided for such a bottle having a rectangular cross section. In the case of a square cross section, it is provided on all four side walls, and in the case of a rectangular cross section, a long side which is easily bent and deformed. A pressure reducing panel is formed on each of the wall surfaces.
[0009]
The decompression panels are generally formed at two locations above and below the wall of the bottle.
[0010]
Some bottles of this type have a chamfered portion formed at a position where each side intersects to connect each side. The reason for forming the chamfered portion is to ensure the strength at the corner of the bottle, that is, at the position where the sides forming the wall intersect. Therefore, the cross-sectional shape of such a bottle is an octagon.
[0011]
[Problems to be solved by the invention]
However, among the containers described above, in the case of a square cross-section, the deformation in appearance is small because the decompression deformation during the volume reduction and decompression is performed almost uniformly on the wall surface of each side. In the case of bottles having different side lengths, the wall shape of the shorter side may bulge and the external shape may change.
[0012]
That is, at the time of filling the high-temperature contents, the wall portion is easily swelled and deformed by the liquid pressure and the thermal deformation of the wall portion, and at the time of cooling thereafter, the wall portion is easily dented and deformed into the bottle by decompression. In this case, since the wide wall portion is more easily dented, the reduced pressure deforming portion is deformed, but the narrow wall portion is hardly dented and deformed. Therefore, if the swelling deformation occurs, the state is maintained as it is.
[0013]
Therefore, when the lateral ribs are formed on the narrow wall portion, the bulging deformation at the time of heat filling is prevented. However, since the reduced-pressure deformation is not expected at all in the narrow wall portion, the role of the other wall portion, particularly, the wide wall portion formed below is increased.
[0014]
By the way, if the hot filling temperature is set higher than expected, or if the external force due to the impact during transportation or the deformation due to the pressure at the time of grasping by the consumer is applied to the wide wall portion where the burden is large, the wide There has been a problem that the surface of the wall other than the depressurized deformed portion may be deformed and may not be able to return to its original state.
[0015]
Such deformation of the wall surface located between the decompression panels at the time of volume reduction and decompression was often observed particularly near the upper part of the lower decompression panel.
[0016]
The present invention has been made in view of the above-mentioned problems, and its purpose is to prevent the wall surface from swelling when, for example, heating and filling the contents, and to reduce the wall surface other than the pressure reducing panel during the volume reduction and pressure reduction. It is an object of the present invention to provide a biaxially stretched blow-molded container that can be prevented from being concavely deformed.
[0017]
[Means for Solving the Problems]
In order to achieve the above object, a first invention is as follows.
Has a chamfer at the intersection of the wide wall and the narrow wall portion, of the wall portion which is formed in cross section substantially rectangular shape, in the height direction substantially central position below the wide wall In a biaxially stretched blow-molded container provided with a reduced pressure deforming part at the time of reducing the volume,
Having a rib depressed over the narrow wall portion and the chamfer portions on both sides thereof,
The rib depth in the central region in the longitudinal direction of the rib is smaller than the rib depth in both end regions.
[0018]
In a second aspect, in the first aspect,
The ribs in the both end regions extend from the chamfered portion to a narrow wall portion.
[0019]
The third invention is
Has a chamfer at the intersection of the wide wall and the narrow wall portion, of the wall portion which is formed in cross section substantially rectangular shape, in the height direction substantially central position below the wide wall In a biaxially stretched blow-molded container provided with a depressurized deformation portion having a concave portion deformed under reduced pressure when reducing the volume,
Having a rib depressed over the narrow wall portion and the chamfer portions on both sides thereof,
A rib depth of at least a central region in the longitudinal direction of the rib is smaller than a depth of a concave portion of the reduced pressure deforming portion.
[0020]
[Action]
According to the first aspect of the present invention, when the content is heated and filled, the narrow wall portion is reinforced by ribs depressed over the chamfer portions on both sides thereof. Therefore, even if the weight of the contents, the pressure applied from the deformed wall portion, or even the thermal deformation is applied, the bulging deformation of the lower portion of the narrow wall portion is prevented.
[0021]
In particular, when the rib depth in the central region in the longitudinal direction of the rib is made shallower than the rib depth at both ends, when a pressure equal to or more than a certain reduced pressure is applied to the narrow wall portion, the pressure is reduced. It becomes possible to absorb by deformation.
[0022]
Therefore, the deformation of the wall due to the decompression deformation force is stopped in the decompression deformation portion, so that the commercial value is not impaired.
[0023]
According to the second invention, the ribs at both end regions, which are deeper than the ribs at the center region, are extended from the chamfered portions to the narrow wall portions, so that the ribs at both end regions are narrowed at the narrow wall. Reinforces both sides of the wall, reliably preventing the entire narrow wall from bulging and deforming even if the weight of the contents, the pressure applied from the deformed wall, or even thermal deformation is applied can do.
[0024]
Further, even when a reduced pressure deformation force is applied to the reduced pressure deformation portion beyond a certain reduced pressure value at the time of reducing the volume of the contents, the ribs in the narrow wall portion do not deform the chamfered portion. Only the part can be deformed under reduced pressure.
[0025]
Therefore, the deformation of the wall due to the internal pressure or the reduced pressure is stopped in the narrow wall so as not to impair the commercial value.
[0026]
In the third invention, as in the first invention, the weight of the contents and the pressure applied from the deformed wall portion are reduced by the ribs recessed over the narrow wall portion and the chamfer portions on both sides thereof. Furthermore, even if thermal deformation or the like is applied, it is possible to reliably prevent the entire narrow wall portion from expanding and deforming.
[0027]
Further, even when a decompression deformation force is applied to the decompression deformed portion beyond a certain decompression value at the time of reducing the volume of the content, the rib depth in the central portion in the longitudinal direction increases the depth of the concave portion of the decompression deformation portion. Since it is shallower than that, the rib in the central region is deformed and can absorb the reduced pressure.
[0028]
【Example】
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
[0029]
1 to 3 are cross-sectional views of a biaxially stretch blow-molded container (hereinafter, referred to as a bottle) according to one embodiment of the present invention.
[0030]
The bottle 10 shown in this embodiment is made of, for example, polyethylene terephthalate (PET) by biaxial stretch blow molding, and has a lip portion 12 including an upper end side opening and a shoulder extending downward from the lip portion 12. A part 14, a bottom part 16 on the lower end side, a heel part 18 extending upward from the bottom part 16, and a body part 20 formed between the heel part 18 and the shoulder part 14 are integrally formed. Has become.
[0031]
Barrel 20 is formed in the lateral cross section rectangular shape having a pair of wide walls 22 and narrow walls 24 disposed on each opposing positions. In the body portion 20, a chamfered portion 26 is formed at the intersection of each wide wall portion 22 and each narrow wall portion 24 in the height direction. The chamfered portion 26 is formed narrower than the narrow wall portion 24, and reinforces the intersection of the wide wall portion 22 and the narrow wall portion 24. That is, in the trunk portion 20, the chamfered portion 26 is disposed at each intersection of the wide wall portion 22 and the narrow wall portion 24, and the chamfered portion 26 is narrower than the narrow wall portion 24. Therefore, four intersections of the wall portions 22 and 24 are reinforced by a chamfer 26 having higher strength than the wall portions 22 and 24.
[0032]
Further, a groove 28 that is depressed inward is formed at a position above the center position in the height direction of the body portion 20. The groove 28 is provided continuously in the circumferential direction over the wide wall portion 22, the narrow wall portion 24, and the chamfered portion 26. The body portion 20 is separated from the groove portion 28 by the upper body portion. 30 and a lower trunk 32. As described above, the groove 28 is formed at an intermediate position in the vertical direction of the trunk 20, thereby reinforcing the side pressure of the trunk 20 at an intermediate position in the vertical direction of the trunk 20, and at the same time, the trunk 20 is connected to the upper trunk. By dividing the lower part 30 and the lower trunk part 32 into small units in the vertical direction, buckling deformation of the trunk part 20 is prevented.
[0033]
Further, the lower body portion 32, which receives a large amount of liquid pressure from the filled contents, has a wide wall portion 22 provided with a reduced pressure deformable portion 34 capable of being deformed under reduced pressure when reducing the volume of the contents. The portion 24 is provided with a rib 36 for preventing outward expansion when the content is heated and filled or the wide wall portion 22 is gripped.
[0034]
The decompression deforming portion 34 is formed in a vertically elongated substantially rectangular shape at the center of the lower body portion 32 of the wide wall portion 22, and inside the decompression deformation portion 34, the decompression deformation portion 34 of the wall 22 is provided. A concave portion 38 which is depressed inward from an outer surface (hereinafter, referred to as a general surface) is formed in an annularly continuous state, and a central portion surrounded by the concave portion 38 has a lower portion than the general surface of the wall portion 22. A flat portion 40 located slightly inward is formed continuously from the concave portion 38. When the volume of the content is reduced and the pressure is reduced, the flat portion 40 can be deformed in a reduced pressure inward with the outer peripheral edge of the concave portion 38 as a hinge fulcrum.
[0035]
Further, a reinforcing groove 42 extending in the lateral direction is formed at an upper position in the reduced-pressure deforming portion 34. The reinforcing groove 42 is formed in a state recessed inward and deeper than the concave portion 38 formed around the depressurized deformation portion 34 and functions as a reinforcing rib. The general surface of the wall portion 22 connected to the upper portion of the reduced pressure deforming portion 34 is prevented from being deformed due to the reduced pressure deformation of the reduced pressure deforming portion 34. Further, the reinforcing groove 42 is provided in the decompressed deformation portion 34 so as to extend from the upper end position of the concave portion 38 of the decompressed deformed portion 34 to an intermediate position of the wall portion 22 continuing thereabove. The space between the wall and the groove 28 is narrowed. Accordingly, a reinforcing rib is formed between the reinforcing groove 42 and the groove 28, and the rib effect is enhanced. Further, the general surface of the wall portion 22 connected to the upper portion of the reduced pressure deforming portion 34 is further reduced. It is possible to reliably prevent deformation due to the decompression deformation of 34. Further, a reinforcing step portion 45 is provided in a rising portion 43 between the bottom portion of the reinforcing groove 42 and the general surface located above the decompression deforming portion 34 to reinforce the rising portion 43, so that the upper end of the concave portion 38 is securely hinged. It is to be.
[0036]
The plurality of ribs 36 (five in this embodiment) are provided at predetermined intervals in the height direction of the narrow wall portion 24 over the entire area in the width direction. , The wall 24 is prevented from bulging when the content is heated and filled or when the wide wall 22 is gripped.
[0037]
Further, at both end portions of each rib 36, an extension portion 44 is provided which extends beyond the corner where the narrow wall portion 24 and the chamfered portion 26 intersect and extends over both adjacent chamfered portions 26. By extending the ribs 36 to the chamfered portions 26 on both sides, both end portions of the ribs 36 can be supported by the chamfered portions 26 which are narrower than the narrow wall portions 24 and have high bending strength. The bulging of the wall portion 24 can be reliably prevented.
[0038]
Further, the ribs 36 are formed such that the depth D2 of the ribs 36 in the central region in the longitudinal direction in the narrow wall portion 24 is smaller than the depth D1 of the extension portions 44 formed in both end regions thereof, and the ribs are deformed under reduced pressure. When a pressure reduction deformation force equal to or greater than a predetermined pressure reduction value is applied to the portion 34, the rib 36 portion of the narrow wall portion 24, which is shallower than the extension portion 44, can be deformed by pressure reduction, and The general structure of the wall portion 22 connected to the upper portion of the reduced pressure deforming portion 34 provided on the 22 is prevented from being deformed by reduced pressure.
[0039]
In addition, the depth D2 of the rib portion 36 in the narrow wall portion 24 is formed to be smaller than the depth D3 of the concave portion 38 in the reduced pressure deforming portion 34 provided in the wide wall portion 22, and is fixed to the reduced pressure deforming portion 34. Is provided on the wide wall portion 22 so that the rib portion 36 of the narrow wall portion 24 which is shallower than the concave portion 38 can be easily decompressed and deformed when a decompression deformation force greater than the decompression value is applied. The wall 22 connected to the upper part of the reduced pressure deforming portion 34 is prevented from being deformed under reduced pressure.
[0040]
Further, the wide wall portion 22 and the narrow wall portion 24 of the upper body portion 30 are provided with decompression deformable portions 46 and 48, respectively, which can be decompressed and deformed when reducing the volume of the contents. In the wide wall portion 22, the reduced pressure deforming portion 46 is formed large, and in the narrow wall portion 24, the reduced pressure deforming portion 48 is formed relatively small. Further, in the upper body portion 30, the area is smaller than that of the lower body portion 32, and the strength of the wide wall portion 22 and the narrow wall portion 24 is high, so that the decompression deformation portions 46, 48 have the concave portions 50, 52 and It is composed of only the flat portions 54 and 56, has no reinforcing groove, and has no rib provided on the narrow wall portion 24.
[0041]
Since the present embodiment is configured as described above, when the contents are heated and filled, a liquid pressure is applied to the body 20, and a pressure in the bulging direction is applied to the body 20, especially the lower body 32. Even in this case, since the narrow wall portion 24 of the lower body portion 32 is reinforced by the ribs 36, the swelling state is prevented. Particularly, since the ribs 36 are in a state where both ends are extended to and supported by the chamfered portion 26 having high strength, the bulging of the wall portion 24 is reliably prevented.
[0042]
Further, even if the internal pressure is increased by gripping the wide wall portion 22 of the body portion 20, the presence of the rib 36 ensures that the narrow wall portion 24 is prevented from bulging. Become.
[0043]
Further, even when the volume of the heat-filled contents is reduced in pressure, the reduced pressure deforming portions 46 and 48 of the upper body 30 and the reduced pressure deforming portion 34 provided on the wide wall 22 of the lower body 32 are decompressed. It deforms and responds to volume reduction of the contents.
[0044]
In this case, with the decompression deformation of the decompression deformation portion 34 in the lower body portion 32 during decompression, the general surface of the wall portion 22 connected to the upper portion of the decompression deformation portion 34 is easily deformed. The depth D2 of the rib 36 is smaller than the depth D1 of the extension portion 44 formed at both ends, and the depth D2 of the rib 36 in the narrow wall portion 24 is equal to the width D2 of the wide wall portion 22. Is formed to be shallower than the depth D3 of the concave portion 38 in the reduced pressure deforming portion 34 provided when the pressure reducing deforming force is applied to the reduced pressure deforming portion 34 at a predetermined pressure value or more. Is reliably deformed under reduced pressure, so that the reduced pressure deformation of the general surface of the wall portion 22 connected to the upper portion of the reduced pressure deforming portion 34 provided on the wide wall portion 22 is prevented.
[0045]
Further, the deformation of the general surface is more reliably prevented by reinforcing the reinforcing groove 42 provided in the upper part inside the reduced-pressure deforming portion 34. In particular, the reinforcing groove 42 is recessed inward more deeply than the concave portion 38 formed in the reduced pressure deforming portion 34 and extends above the reduced pressure deforming portion 34 as described above, so that the groove portion formed in the body 20 is formed. Since the interval between the general surface of the wall portion 22 between the groove 28 and the reinforcing groove 34 is reduced and functions as a reinforcing rib, the deformation of the general surface is more reliably prevented.
[0046]
The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the present invention.
[0047]
For example, in the above embodiment, no rib is formed on the upper body, but a label or the like is often affixed on the upper body, and a portion such as a chamfered portion which does not affect the attachment of the label or the like is provided. It is possible to form ribs.
[0048]
Further, in the present embodiment, the depth D2 of the rib 36 in the narrow wall portion 24 is formed to be smaller than the depth D1 of the extension portions 44 formed at both ends, and the narrow wall portion 24 is formed. Is formed to be shallower than the depth D3 of the concave portion 38 in the reduced pressure deforming portion 34 provided in the wide wall portion 22, but the relationship of this depth is narrower. It is also possible to have only one of the relationship between the rib portion in the wall portion and the concave portion or the extension portion.
[0049]
Further, it is also possible to extend the extension portion 44 while keeping the depth of the rib portion 36 in the narrow wall portion 24.
[0050]
【The invention's effect】
As described above, in the first invention, the state in which the narrow wall portion is reinforced by the ribs recessed over the narrow wall portion and the chamfer portions adjacent to the narrow wall portion when the content is heated and filled. Therefore, even if the weight of the contents, the pressure applied from the deformed wall portion, or even the thermal deformation is applied, there is an effect that the bulging deformation on the lower side of the narrow wall portion is prevented.
[0051]
In particular, when the rib depth in the central region in the longitudinal direction of the rib is made shallower than the rib depth at both ends, when a pressure equal to or more than a certain reduced pressure is applied to the narrow wall portion, the pressure is reduced. It becomes possible to absorb by deformation.
[0052]
Therefore, there is an effect that the deformation of the wall portion due to the decompression deformation force is stopped in the decompression deformation portion so that the commercial value is not impaired.
[0053]
According to the second aspect, the ribs at both end regions, which are deeper than the ribs at the center region, are extended from the chamfered portions to the narrow wall portions, so that the ribs at both end regions are narrowed at the narrow wall portions. Reinforced on both sides, and even if the weight of the contents, the pressure applied from the deformed wall, or even thermal deformation is applied, the entire narrow wall is reliably prevented from bulging and deforming. There is an effect that can be.
[0054]
Further, even when a reduced pressure deformation force is applied to the reduced pressure deformation portion beyond a certain reduced pressure value at the time of reducing the volume of the contents, the ribs in the narrow wall portion do not deform the chamfered portion. There is an effect that only the portion can be deformed under reduced pressure.
[0055]
Therefore, there is an effect that deformation due to internal pressure or reduced pressure of the wall portion is stopped in the narrow wall portion so as not to impair the commercial value.
[0056]
According to the third invention, similarly to the first invention, the weight of the contents, the pressure applied from the deformed wall, and the pressure applied from the deformed wall are reduced by the ribs recessed over the narrow wall and the chamfers on both sides thereof. Has the effect that even if thermal deformation or the like is applied, the entire narrow wall portion can be reliably prevented from bulging and deforming.
[0057]
Further, even when a decompression deformation force is applied to the decompression deformed portion beyond a certain decompression value at the time of reducing the volume of the content, the rib depth in the central portion in the longitudinal direction increases the depth of the concave portion of the decompression deformation portion. Since it is shallower than that, the ribs in the central region are deformed and there is an effect that the reduced pressure can be absorbed.
[Brief description of the drawings]
FIG. 1 is a front view of a biaxially stretch blow-molded container according to one embodiment of the present invention, as viewed from a wide wall side.
FIG. 2 is a partially broken front view as viewed from a narrow wall side in FIG. 1;
FIG. 3 is a sectional view taken along the line III-III in FIG. 1;
[Explanation of symbols]
10 Bottle 20 Body 22 Wide Wall 24 Narrow Wall 26 Chamfer 28 Groove 30 Upper Body 32 Lower Body 34 Decompression Deformation Section 36 Rib 38 Recess 42 Reinforcement Groove 44 Extension

Claims

Has a chamfer at the intersection of the wide wall and the narrow wall portion, of the wall portion which is formed in cross section substantially rectangular shape, in the height direction substantially central position below the wide wall In a biaxially stretched blow-molded container provided with a reduced pressure deforming part at the time of reducing the volume,
Having a rib depressed over the narrow wall portion and the chamfer portions on both sides thereof,
A biaxially stretch blow-molded container, characterized in that the rib depth in the central region in the longitudinal direction of the rib is smaller than the rib depth in both end regions.

In claim 1,
The biaxially stretched blow-molded container, wherein the ribs at both end regions extend from the chamfered portion to a narrow wall portion.

Has a chamfer at the intersection of the wide wall and the narrow wall portion, of the wall portion which is formed in cross section substantially rectangular shape, in the height direction substantially central position below the wide wall In a biaxially stretched blow-molded container provided with a depressurized deformation portion having a concave portion deformed under reduced pressure when reducing the volume,
Having a rib depressed over the narrow wall portion and the chamfer portions on both sides thereof,
A biaxially stretch blow-molded container, wherein a depth of a rib in at least a central region in a longitudinal direction of the rib is smaller than a depth of a concave portion of the depressurized deformation portion.