JP3990801B2

JP3990801B2 - Injection molding simultaneous painting device

Info

Publication number: JP3990801B2
Application number: JP06566498A
Authority: JP
Inventors: 浩之阿竹
Original assignee: Dai Nippon Printing Co Ltd
Current assignee: Dai Nippon Printing Co Ltd
Priority date: 1998-03-16
Filing date: 1998-03-16
Publication date: 2007-10-17
Anticipated expiration: 2018-03-16
Also published as: JPH11254480A

Description

【０００１】
【発明の属する技術分野】
本発明は、射出成形と同時に成形品に絵付シートを一体的に接着して図柄や文字等が施された成形品を得るようにした射出成形同時絵付装置に関する。
【０００２】
【従来の技術】
帯状シート又は枚葉シートからなる絵付シートを雌型と雄型との間に供給して射出成形と同時に成形品の表面に絵付シートを一体的に接着する射出成形同時絵付方法としては、熱盤等により絵付シートを予め加熱軟化させた後、真空成形及び／又は圧空成形により雌型のキャビティに沿わせて密着させ（予備成形工程）、しかる後、雌型と雄型との型締めを行って、射出成形機からの流動状態の樹脂（熔融樹脂等）を前記雄型に設けられたランナー及びゲートを通じて前記雌型のキャビティへ射出充填して射出成形を行うようにしたもの（特公昭５０−１９１３２号公報等を参照）、あるいは、予備成形工程なしで絵付シートを平坦なまま雌雄両金型間に挟み込み、雄型側から注入充填される樹脂の熱と圧力で絵付シートを雌型キャビティ面に沿わせると同時に成形品表面に接着するもの（特公平２−４２０８０号公報参照）等が一般的である。
【０００３】
このような射出成形同時絵付に使用される絵付シートとしては、製品種別に応じて貼合わせ積層シート（ラミネートシート）と転写シートのいずれかが用いられ、ラミネートシートである場合には、射出成形によりそのままで絵付けが行われたことになり、射出成形品の外表面にシート全層が接着一体化して化粧層となる。それに対し、絵付シートが転写シートである場合には、成形品外表面に一体化した化粧シートのうちの支持体シートを剥離し、装飾層等の転写層を成形品側に残留させて化粧層となすことにより絵付けが完了する。
【０００４】
ところで、上述の如くの射出成形同時絵付を行うにあたっては、雄雌両成形型を備えた射出成形同時絵付装置が用いられるが、該装置の雄型には、射出成形機からの熔融樹脂等を雌型のキャビティに注入充填するために、通常、コールドランナーもしくはホットランナーが設けられる。
しかしながら、コールドランナー方式の射出成形同時絵付装置においては、雌型だけでなく雄型も大きく移動させる必要がある。つまり、絵付成形品の取り出し時に、ランナーの硬化樹脂を取り除くために、雄型を固定盤から雌型側へ移動させることが必要であるが、雄型を雌型２側に移動させた状態では雌型と雄型との離隔距離が短くなり、自動取り出し機がそれらの間に挿入できなくなる等の問題が生じ、かかる問題を回避するには、雌型と雄型との離隔距離、すなわち型開き量を大きくしなければならず、得るべき成形品に比して装置の占有スペースあるいは装置の寸法自体が極めて大きくなるとともに、一サイクルに要する時間が長くなり、生産性の面でも良いとは言えなかった。さらに、成形型周辺の機構が複雑となるという難点もある。
【０００５】
そこで、射出成形同時絵付装置においては、ホットランナー方式のものが使用されることが多い。このホットランナー方式の射出成形同時絵付装置の代表的な例を図１１〜図１３を参照しながら簡単に説明する。図示例の射出成形同時絵付装置４０は、固定盤４１に取り付けられた雄型４５と、この雄型４５に対して接近離隔する方向〔ここでは、図１２のＹ方向（左右方向）〕に移動せしめられる雌型２５とを備えており、前記雄型４５には、射出成形機のノズル７０から熔融樹脂が供給される、電熱線等からなるヒーター４４に包囲された門形二股状のホットランナー４６が設けられており、このランナー４６の両先端には雌型２５のキャビティ２６、２６（二個取り式）に該ランナー４６からの熔融樹脂を射出する直線状の柱状ゲート４７、４７が連設されている。
【０００６】
一方、前記雌型２５の二つのキャビティ２６、２６の間（中央部）には、製品外となる凸状隔壁部２７が突設されている。また、雌型２５には、絵付シートＳを雌型パーティング面２５ａに固定保持するための矩形枠状ないし井桁状のクランパー３２がその四隅を摺動ロッド３４，３４，３４，３４に支持されて進退動可能に配置されている。なお、クランパー３２は、雌型２５の底部に格納された流体圧シリンダ等の駆動機構により作動せしめられる。また、前記雌型２５のパーティング面２５ａにおけるクランパー３２に対向する部位には気密性保持のためにＯリング３７が嵌め込まれている。
【０００７】
また、前記キャビティ２６、２６には、絵付シートＳをキャビティ面に沿うように延伸させるための真空吸引孔３６が開口せしめられており、この真空吸引孔３６は、雌型２５の内部に穿設された真空吸引通路３８を介して外部の真空源に接続された吸気管３９に連結されている。
なお、本願明細書の添付図面（図１〜図１９）においては、前記絵付シートＳの厚みや真空吸引孔３６の孔径等は、よりわかりやすくするため、及び、作図上の都合等により、実寸より大きく誇張して描かれている。
【０００８】
上記射出成形同時絵付装置４０においては、絵付シートＳの次ショット部分を雌型２５のパーティング面２５ａとクランパー３２との間に供給し、この絵付シートＳをクランパ−３２により雌型２５のパーティング面２５ａに押圧固定した後、図示していない熱盤等により加熱軟化させ、かつ、前記真空吸引孔３６等からなる真空吸引手段により真空吸引して雌型２５のキャビティ２６、２６に沿わせるように延伸させ（予備成形）、しかる後、雌型２５を雄型４５側へ移動させて型締めを行い、雌型２５のキャビティ２６、２６内にそれぞれ雄型４５のランナー４６及びゲート４７を通じて熔融樹脂を注入充填して射出成形を行い、その後、射出充填された樹脂が冷却硬化した後（図１３参照）、絵付シートＳが接着積層された積層製品１、１を取り出すべく、雌型２５と雄型４５とを離間させる型開きを行う。
【０００９】
この型開きにより、雌型２５は雄型４５及び絵付成形品（製品１、１）から離れ、絵付シートＳが接着された製品１、１は、雄型４５のコア部４３に付着した状態で残る。次に、この雄型４５に残った製品１、１を、例えば雄型４５側からエジェクターピン５７、５７（後述する図１４参照）や圧縮エアー等により雌型２５側に突き放して取り出す取出工程が行われる。
この取り出し工程では、前記ゲート４７，４７で硬化したピン状の樹脂４７、４７が製品１、１に付随したまま取り出されるので、これを適宜の手段で切除する。
【００１０】
ところが、かかる射出成形同時絵付装置４０においては、成形条件等によっては、図１３に示される如くに、ランナー４６の先端部付近（ゲート４７、４７の後端付近）に冷えて硬化した樹脂７'、７'が残り、この冷えた硬化樹脂の残渣が次の射出成形時に雌型キャビティ２６、２６内に射出されて絵付シートＳに当てられ、該絵付シートＳとの間に密着不良等を引き起こし、得られた製品１、１に接着不良や柄（インキ）抜け等の絵付・成形不良を生じることがあった。
【００１１】
そこで、上記のような欠点を解消し、成形品に接着不良や柄抜け等の絵付成形不良を生じ難くされ、歩留りや信頼性を向上できるようした射出成形同時絵付装置を本出願人は先に提案している（特開平９−１５０４３３号公報参照）。この装置１０は、図１６、図１７に示される如くに、前記図１１〜図１３に示されるものと基本的には同一の雌型２５と雄型１２とを備え、雄型１２には、電熱線等からなるヒーター１４に包囲されたホットランナー１３と柱状のゲート１６、１６（プラッグ部）とが設けられとともに、それらの間に、往路９ａ、流出部９ｂ、及び２本の復路９ｃ、９ｃからなるＵターン型サブマリンゲート９が設けられ、前記ランナー１３からの熔融樹脂を往路９ａ及びその先端の流出部９ｂを通じて、前記雌型２５における前記絵付シートＳは密着せしめられるが熔融樹脂は充填されない製品外となる前記凸状隔壁部２７へ導出するとともに、復路９ｃ、９ｃを通じてそこからＵ字ないしＶ字を描くように折り返して前記柱状ゲート１６、１６に導き、この柱状ゲート１６、１６から本来のキャビティ２６、２６内（製品部１、１）に注入充填するようにされる。
【００１２】
このようにされることにより、たとえランナー１３の先端部付近に冷えて硬化した樹脂７'、７'が残っていても、この冷えて硬化した樹脂７'、７'の残渣は、次の射出成形時に、Ｕターン型サブマリンゲート９の往路９ａ及び流出部９ｂを通じて先頭に立って真っ先に、雌型２５における絵付シートは密着しているが熔融樹脂は充填されない製品外となる凸状隔壁部２７に導出されて捕捉され、製品部１、１には導かれない。
【００１３】
そのため、成形品に接着不良や柄抜け等の絵付成型不良を生じ難くできる。
なお、図１６、図１７の装置１０においては、雄雌両成形型１２、２５の型開き後に、外表面に絵付シートＳが接着積層された製品１、１が圧縮エアーやイジェクターピン５７等（後述する図１８、図１９参照）により取り出される。この場合、前記ゲート１６、１６で硬化したピン状の樹脂８が製品１に付随したまま取り出されるるとともに、このとき前記ゲート１６、１６で硬化したピン状の樹脂８と前記Ｕターン部９（の復路９ｃ、９ｃ）で硬化した樹脂７との連結部が押し切られて分離し、Ｕターン部９で硬化した樹脂７は前記製品１、１の取り出し時にエジェクターピン５９等で雄型２５内から突き出される。
【００１４】
【発明が解決しようとする課題】
しかしながら、先に述べた図１１〜図１３に示される従来の一般的なランナー４６、ゲート４７を備えた射出成形同時絵付装置４０、及び図１６、図１７に示されるＵターン型サブマリンゲート９を備えた射出成形同時絵付装置１０においては、それぞれ次のような問題が生じるおそれがあった。
すなわち、図１１〜図１３に示される装置４０においては、図１４に示される如くに、雄型４５に付着している製品１、１をエジェクターピン５７、５７（図１４）や圧縮エアー等により雄型４５から引き剥がすようにして取り出す取出工程が行われるが、この取出工程においては、通常、絵付シートＳのうちの接着付随部分Ｓａが接着されている製品部１、１がエジェクターピン５７、５７等で突き出される。この製品部１、１と製品外となる部分（絵付シートＳのうちの製品外となる部分Ｓｂ）とは、例えば、絵付シートＳの製品外部分Ｓｂが雄型４５に貼り付く等して、該製品外部分Ｓｂが雄型４５から離れるタイミングが前記製品部１、１が雄型４５から突き放されるタイミングより遅れる（あるいは、その逆）等に起因して、絵付シートＳの製品外部分Ｓｂが図１４の矢印Ｆで示される如くに製品１、１から離れる方向に引っ張られ、図１５に示される如くに、絵付シートＳの接着付随部分Ｓａが製品部１の側端面１ａのエッジ部分Ｅから引き剥がされてしまう（剥がれた部分Ｚ）。
【００１５】
このように絵付シートＳが引き剥がされると、得られた製品部１は接着不良や柄抜け等を有する絵付成形不良品となる。
一方、図１６、図１７に示されるＵターン型サブマリンゲート９を備えた射出成形同時絵付装置１０においては、上記と同様な理由加えて、下記のような理由から前記絵付シートＳが剥がれるという問題がより発生しやすくなる。
すなわち、図１８、図１９に示される如くに、型開き後の製品部１、１の取り出し時に、製品部１、１をエジェクターピン５７、５７等で、また、前記Ｕターン型サブマリンゲート９で硬化したＵターン部内樹脂７をエジェクターピン５９で雄型１２から突き出す際、Ｕターン型サブマリンゲート９の復路９ｃで硬化した復路内樹脂部７ｃ、７ｃは、復路９が突き出し方向に対して窄まるように傾斜している関係上、突き出し距離が増加する従い、復路９ｃ壁面に押されて弾性変形し、図１８に示される如くに、往路９ａで硬化した往路内樹脂部７ａ側に強制的に湾曲せしめられる。
【００１６】
そして、さらに突き出し距離が増加すると、前記Ｕターン部内樹脂７は、製品部１、１よりも少し遅れて雄型１２から突き出されるとともに、前記ゲート１６、１６で硬化したピン状の樹脂８、８より先に雄型１２から抜け出る。この場合、前記復路内樹脂部７ｃは弾性変形せしめられているので、雄型１２から抜け出るとき、そのバネ作用により、はじけるように飛び出す。
これらの作用により、絵付シートＳに貼りついている前記Ｕターン部内樹脂７が雄型１２から突き出されたとき、図１９に示される如くに、絵付シートＳの製品外部分Ｓｂを例えば図の矢印Ｆ方向に引っ張り、絵付シートＳの接着付随部分Ｓａが製品部１の側端面１ａのエッジ部分Ｅから引き剥がされてしまう（剥がれた部分Ｚ）。
【００１７】
このように絵付シートＳが引き剥がされると、得られた製品は接着不良や柄抜け等を有する絵付成形不良品となる。
本発明は、上述の如くの問題を解消すべくなされたもので、その目的とするところは、コスト増や作業効率の低下を招くことのない比較的簡単な構成を付加することによって、製品部の取出工程において、絵付シートが特定方向に引っ張られることがあっても、絵付シートが製品部から引き剥がされ難くされた射出成形同時絵付装置を提供することにある。
【００１８】
【課題を解決するための手段】
上述の目的を達成すべく、本発明に係る射出成形同時絵付装置は、基本的には、雌雄両成形型を備え、前記雌型のパーティング面上に供給された絵付シートをクランプ手段によって前記パーティング面上に押圧固定した後、該絵付シートを真空吸引手段等により前記雌型キャビティに沿って密着させるべく延伸させるとともに、前記雌雄両成形型の型締めを行った後、射出成形機からの流動状態の樹脂を前記雄型に設けられたランナー及びゲートを通じて前記雌型のキャビティへ射出充填し、この樹脂が固化した後、前記雌雄両成形型の型開きを行って、前記絵付シートが、固化した樹脂の側端面に接着された部分を有して接着積層された積層製品を前記雄雌両成形型から取り出すようにされてなる。
【００１９】
そして、前記雌型における前記絵付シートは密着せしめられるが流動状態の樹脂は充填されない製品外となる部分に、絵付シートに引張力吸収用の余剰延伸部を形成するための引張力吸収用溝又は凸部が形成されていることを特徴としている。
前記引張力吸収用溝又は凸部は、絵付シートが接着されている樹脂の前記側端面に沿って並設して配置することが好ましく、その断面外形（図３の如き方向から見た断面）は矩形、カドの丸くなった矩形、半楕円、半円、三角形、Ｗ形等のいずれでもよい。但し、引張力吸引効果を有効に作用させるためには、半円、半楕円の如き丸みを帯びた形状が好ましい。特に、該溝又は凸部の外部の断面の直線部と該溝又は凸部内の断面の直線又は曲線部とが連続的になめらかに接続することが好ましい。
【００２０】
このような構成とされた本発明に係る射出成形同時絵付装置においては、絵付シートを真空吸引等により延伸させて雌型キャビティに沿わせるように密着させる延伸工程時に、絵付シートは製品外部分（凸状隔壁部等）にも密着せしめられており、したがって、その製品外部分に設けられている引張力吸収用溝又は凸部にも絵付シートが密着する。したがって、絵付シートには前記引張力吸収用溝又は凸部の断面形状に応じて例えば断面凹状又は凸状の余剰延伸部が形成されている。
【００２１】
そして、製品を雄型（又は雌型）から取り出すときには、絵付シートに製品部から引き離す方向の引張力が作用しても、絵付シートのうちの前記引張力吸収用溝又は凸部により形成されている例えば断面凹状又は凸状の余剰延伸部が展開して、前記引張力が吸収され、絵付シートのうちの製品部に接着付随させるべき部分には大きな引張力が作用しなくなる。
したがって、本発明装置によれば、製品取出時に、絵付シートが製品部から引き剥がす方向に引っ張られることがあっても、絵付シートの製品外部分のうちの引張力吸収用溝又は凸部よって形成された余剰延伸部によって、引張力が吸収されるので、絵付シートのうちの製品部に接着付随させるべき部分は製品部から引き剥がされ難くされ、その結果、接着不良や柄抜け等のない良質の製品が得られ、しかも、引張力吸収用溝又は凸部という簡単な構成を付加するだけで済むので、コスト増や作業効率の低下を招くこともない。
【００２２】
本発明の好ましい態様では、前記射出成形機からの流動状態の樹脂は、前記ランナーとゲートとの間に設けられ、前記ランナーからの流動状態の樹脂を前記雌型における製品外となる部分に導出するとともにそこから折り返して前記ゲートに導くＵターン型のゲートを通じて前記雌型のキャビティに導かれるようにされ、より好ましくは、前記引張力吸収用溝又は凸部は、前記流動状態の樹脂が射出充填される製品部と前記Ｕターン型のゲートで樹脂を導出する雌型における製品外となる部分との間に形成されている。
【００２３】
本発明において、雄雌両成形型は、鉄等の金属あるいはセラミックス等で作製され、成形品形状応じて分割構成等としてもよい。また、絵付シートの予備成形を行う場合には、加熱軟化用の熱盤等を付設したり、雌型及び雄型に真空吸引や圧空供給用（予備成形用）に小孔（真空吸引孔等）を設ける。あるいは、雌型を複数の分割部分の集合体て形成し、各分割部分の間隙から吸気を行うようにしてもよい。なお、凹凸の段差が小さい成形形状の場合は予備成形を省略し得る。
【００２４】
絵付シートは、ロール状に巻き取られた長尺の連続帯状シートの状態から必要量づつ（１ショット分づつ）供給するようにしてもよいし、予め所定寸法に裁断した枚葉シートを供給するようにしてもよい。また、帯状シート（の次ショット部分）もしくは枚葉シートからなる絵付シートを対向配置された雌型と雄型との間に供給するには、巻き出し機及び巻き取り機を用いて帯状シートを連続して毎ショット供給するようにしたロール／ロール方式でもよいし、前記枚葉絵付シートを保持する吸着盤等を備えたロボット（マニュピュレーター）等で搬送する方式でもよいが、生産性の面からはロール／ロール方式が推奨される。
【００２５】
また、絵付シートを雌型パーティング面に固定保持すべくクランプ手段を付設してもよい。クランプ手段としては、枠状の押さえ板等を用いることができ、その駆動は、型締め動作等の成形用駆動力を用いたり、エジェクターピン駆動機構の動力を利用したりすることができる他、別途に流体圧アクチュエーター等の駆動手段を設けることによりなされる。
絵付シートは、基材シートとその上に積層された装飾層からなり、基材シートを成形品と密着一体化させたまま最終製品として使用する貼り合わせ積層シート（ラミネートシート）、あるいは一旦絵付シートと成形品とを一体化させた後、装飾層（転写層）のみを成形品側に残して基材シート（支持体シート）を剥離する転写シートのいずれも使用することができる。
【００２６】
前記基材シートとしては、ポリ塩化ビニル、アクリル、ポリスチレン、ＡＢＳ樹脂、ポリカーボネート、ポリエステル、ポリプロピレン、ポリエチレン等の熱可塑性樹脂を用いることができる。基材シートの厚さは、通常２０〜５００μｍ程度である。装飾層としては、印刷絵柄、着色又は透明塗装、金属薄膜、あるいは、硬質塗膜、防曇塗料、導電性層等の機能性層等を用いることができる。
前記転写シートは、一旦剥離性の支持体シート上に形成した絵柄層等よりなる転写層を、別の被転写体に転移させるためのもので、支持体シート上には必要に応じて離型層を設けても良く、転写層としては、剥離層、装飾層、接着剤層、等からなり、装飾層以外の層は必要に応じて選択する。装飾層としては、絵柄層、金属薄膜層（部分又は全面）あるいは硬質塗膜、防曇塗膜、導電性層等の機能性層から選ばれる。
【００２７】
支持体シートは、ナイロン６、ナイロン６６等のポリアミド、ポリエチレン、ポリプロピレン等のポリオレフィン、ポリ塩化ビニル等、可撓性を有する熱可塑性樹脂フィルムあるいはそれらの積層体が好ましい。
射出成形用の樹脂としては、ＡＢＳ（アクリロニトリル・ブタジエン・スチレン共重合体）樹脂、ポリスチレン、ポリ塩化ビニル、アクリル、ポリカーボネート等の熱可塑性樹脂を加熱熔融したもの、あるいは、二液硬化型、触媒硬化型の樹脂、例えば、ポリウレタン、ポリエステル等の未硬化液等の射出成形同時絵付用として従来より知られている材料を使用でき、製品の要求物性やコスト等に応じて選定される。
【００２８】
【発明の実施の形態】
以下に図面を参照して本発明の実施の形態を詳細に説明する。
図１〜図６は、本発明に係る射出成形同時絵付装置の第１実施形態を示す概略図である。図１〜図６において、前述した図１１〜図１５に示される射出成形同時絵付装置４０における各部に対応する部分には同一の符号を付してそれらの重複説明を省略し、以下においては相違点を重点的に説明する。
【００２９】
図示実施形態の射出成形同時絵付装置４０'においては、雌型２５における、絵付シートＳは密着せしめられるが熔融樹脂は充填されない製品外となる部分である凸状隔壁部２７に、断面角丸矩形の引張力吸収用溝３０、３０が穿設されている。この引張力吸収用溝３０、３０は、前記凸状隔壁部２７における、製品を二個取りするための二つ設けられたキャビティ２６、２６寄りの部位に、それぞれ、前記キャビティ２６、２６に形成される製品部１、１の対向している側端面１ａ、１ａ（絵付シートＳが引き剥がされやすい部分）に沿って平行に並設されている。言い換えれば、引張力吸収用溝３０、３０は、絵付シートＳのうちの製品部に接着付随させるべき部分を引き剥がす方向に対して直交する方向に沿って配置されている。引張力吸収用溝３０、３０と対面する雄型４５の部分は、平坦面でもよいし、あるいは、該溝に収納、嵌合される凸状部となっていてもよい。
【００３０】
なお、本実施形態の射出成形同時絵付装置４０'により得るべき製品１は、湾曲した細長パネルであり、その幅は３０〜８０ｍｍ、長さは３００〜４００ｍｍであり、本装置４０'では、この製品を二個取りできるようになっている。
また、前記絵付シートＳとして、ここでは、アクリル樹脂製の基材シート（厚みは１２５μｍ）と、その上にグラビア印刷法により積層された装飾層（アクリル樹脂と塩化ビニル酢酸ビニル共重合体の１：１重量比混合物の樹脂バインダーと顔料からなるインキで形成された絵柄層）と、接着剤層（塩化ビニル酢酸ビニル共重合体系）とからなり、基材シートを射出樹脂成形体１と密着一体化させたまま最終製品として使用する貼り合わせ積層シート（ラミネートシート）を用いている。前記装飾層（絵柄層）は、柄版を３色組み合わせた木目模様となっており、また、前記接着剤層は、スクリーン線数４０線／ｃｍのグラビアベタ印刷版（版深６０μｍ）を２度用いて（グラビア印刷２色刷りして）形成した厚みが２μｍの層である。
【００３１】
上記のような構成とされた本実施形態の射出成形同時絵付装置４０'においては、絵付シートＳを図示していない熱盤等により加熱軟化させた状態で、真空吸引孔３７等を通じての真空吸引により延伸させて雌型キャビティ２６に沿わせるように密着させる延伸工程時に、絵付シートＳは製品外部分（凸状隔壁部２７）にも密着せしめられており、その製品外部分に設けられている引張力吸収用溝３０、３０にも絵付シートＳが密着する。したがって、絵付シートＳの製品外部分Ｓｂには前記引張力吸収用溝３０、３０の断面形状に応じた断面凹状の余剰延伸部Ｓｃが形成されている。
【００３２】
前記延伸工程後は、雌型２５を雄型４５側へ移動させて型締めを行い、雌型２５のキャビティ２６、２６内にそれぞれ雄型４５のランナー４６及びゲート４７を通じて熔融樹脂を注入充填して射出成形を行い、充填された樹脂が冷却硬化した後、図４に示される如くに、雌型２５を雄型２５から離れる方向に移動させて型開きを行う。この型開きにより、雌型２５は雄型４５及び絵付シートＳが接着積層された製品部１、１から離れ、絵付シートＳが接着積層された製品部１、１は、雄型４５のコア部４３に付着した状態で残る（図４参照）。次に、この雄型４５に残った製品部１、１を、例えば雄型４５側からエジェクターピン５７、５７（図５）や圧縮エアー等により雌型２５側に突き放して取り出す取出工程が行われる。
【００３３】
この取出工程では、図５、図６に示される如くに、製品部１、１を雄型４５から突き放すとき、絵付シートＳの接着付随部分Ｓａを製品１の側端面１ａから引き離す方向の引張力（図５の矢印Ｆ）が作用しても、絵付シートＳのうちの前記引張力吸収用溝３０、３０により製品外部分Ｓｂに形成されている断面凹状の余剰延伸部Ｓｃが展開して、前記引張力が吸収され、絵付シートＳのうちの製品部１に接着付随させるべき部分Ｓａには大きな引張力が作用しなくなる。
【００３４】
したがって、本実施形態の装置４０'によれば、製品取出時に、絵付シートＳが製品部１、１から引き剥がす方向に引っ張られることがあっても、絵付シートＳの製品外部分Ｓｂのうちの引張力吸収用溝３０、３０によって形成された余剰延伸部Ｓｃによって、引張力が吸収されるので、絵付シートＳのうちの製品部１、１に接着付随させるべき部分Ｓａ、Ｓａは製品部から引き剥がされ難くされ、その結果、接着不良や柄抜け等のない良質の製品が得られ、しかも、引張力吸収用溝３０、３０という簡単な構成を付加するだけで済むので、コスト増や作業効率の低下を招くこともない。
【００３５】
なお、前記引張力吸収用溝３０に代えて引張力吸収用凸部（凸条）を設けてもよく、この場合は、雄型側に前記凸部分が収容される凹溝を形成しておく。
図７〜図１０は、本発明に係る射出成形同時絵付装置の第２実施形態を示す概略図である。図７〜図１０において、前述した図１６〜図１９に示される射出成形同時絵付装置１０における各部に対応する部分には同一の符号を付してそれらの重複説明を省略し、以下においては相違点を重点的に説明する。
【００３６】
図示実施形態の射出成形同時絵付装置１０'においても、前記第１実施形態と同様に、雌型２５における、絵付シートＳは密着せしめられるが熔融樹脂は充填されない製品外となる部分である凸状隔壁部２７に、断面角丸矩形の引張力吸収用溝３０、３０が穿設されている。この引張力吸収用溝３０、３０は、前記凸状隔壁部２７における、製品を二個取りするための二つ設けられたキャビティ２６、２６寄りの部位に、それぞれ、前記キャビティ２６、２６に形成される製品部１、１の対向している側端面１ａ、１ａ（絵付シートＳが引き剥がされやすい部分）に沿って平行に並設されている。言い換えれば、引張力吸収用溝３０、３０は、絵付シートＳのうちの製品部に接着付随させるべき部分を引き剥がす方向に対して直交する方向に沿って配置されており、他の構成は、前述した図１６〜図１９に示されるものと同一である。
【００３７】
本実施形態の装置１０'では、ホットランナー１３と柱状のゲート１６、１６（プラッグ部）とが設けられとともに、それらの間に、往路９ａ、流出部９ｂ、及び２本の復路９ｃ、９ｃからなるＵターン型のゲートであるＵターン型サブマリンゲート９が設けられ、前記ランナー１３からの熔融樹脂を往路９ａ及びその先端の流出部９ｂを通じて、前記雌型２５における前記絵付シートＳは密着せしめられるが熔融樹脂は充填されない製品外となる前記凸状隔壁部２７へ導出するとともに、復路９ｃ、９ｃを通じてそこからＵ字ないしＶ字を描くように折り返して前記柱状ゲート１６、１６に導き、この柱状ゲート１６、１６から本来のキャビティ２６、２６内（製品部１、１）に注入充填するようにされているので、たとえランナー１３の先端部付近に冷えて硬化した樹脂７'、７'が残っていても、この冷えて硬化した樹脂７'、７'の残渣は、次の射出成形時に、Ｕターン型サブマリンゲート９の往路９ａ及び流出部９ｂを通じて先頭に立って真っ先に、雌型２５における絵付シートは密着しているが熔融樹脂は充填されない製品外となる凸状隔壁部２７に導出されて捕捉され、製品部１、１には導かれない。
【００３８】
そして、本実施形態の装置においても、絵付シートＳを図示していない熱盤等により加熱軟化させた状態で、真空吸引孔３６等を通じての真空吸引により延伸させて雌型キャビティ２６に沿わせるように密着させる延伸工程時に、絵付シートＳは製品外部分（凸状隔壁部２７）にも密着せしめられており、その製品外部分に設けられている引張力吸収用溝３０、３０にも絵付シートＳが密着する。したがって、絵付シートＳの製品外部分Ｓｂには前記引張力吸収用溝３０、３０の断面形状に応じた断面凹状の余剰延伸部Ｓｃが形成されている。
【００３９】
前記延伸工程後は、雌型２５を雄型１２側へ移動させて型締めを行い、雌型２５のキャビティ２６、２６内にそれぞれ雄型１２のランナー１３及びＵターン型サブマリンゲート９を通じて熔融樹脂を注入充填して射出成形を行い、充填された樹脂が冷却硬化した後、図９に示される如くに、雌型２５を雄型１２から離れる方向に移動させて型開きを行う。この型開きにより、雌型２５は雄型１２及び絵付シートＳが接着積層された製品部１、１から離れ、絵付シートＳが接着積層された製品部１、１は、雄型１２のコア部１９に付着した状態で残る。次に、この雄型１５に残った製品部１、１をエジェクターピン５７、５７等で、また、前記Ｕターン型サブマリンゲート９で硬化したＵターン部内樹脂７をエジェクターピン５９で雄型１２から突き出す。この際、Ｕターン型サブマリンゲート９の復路９ｃで硬化した復路内樹脂部７ｃ、７ｃは、復路９が突き出し方向に対して窄まるように傾斜している関係上、突き出し距離が増加する従い、復路９ｃ壁面に押されて弾性変形し、図９に示される如くに、往路９ａで硬化した往路内樹脂部７ａ側に強制的に湾曲せしめられる。
【００４０】
そして、さらに突き出し距離が増加すると、前記Ｕターン部内樹脂７は、製品部１、１よりも少し遅れて雄型１２から突き出されるとともに、前記ゲート１６、１６で硬化したピン状の樹脂８、８より先に雄型１２から抜け出る。この場合、前記復路内樹脂部７ｃは弾性変形せしめられているので、雄型１２から抜け出るとき、そのバネ作用により、はじけるように飛び出す。
これらの作用により、絵付シートＳに貼りついている前記Ｕターン部内樹脂７が雄型１２から突き出されたとき、図１０に示される如くに、絵付シートＳの製品外部分Ｓｂを図の矢印Ｆ方向に引っ張る。
【００４１】
ここで、本実施形態では、絵付シートＳに前記のような製品部１から引き離す方向の引張力が作用しても、絵付シートＳのうちの前記引張力吸収用溝３０、３０により製品外部分Ｓｂに形成されている断面凹状の余剰延伸部Ｓｃが展開して、前記引張力が吸収され、絵付シートＳのうちの製品部１に接着付随させるべき部分Ｓａには大きな引張力が作用しなくなる。
したがって、本実施形態の装置１０'においても、製品取出時に、絵付シートＳが製品部１、１から引き剥がす方向に引っ張られることがあっても、絵付シートＳの製品外部分Ｓｂのうちの引張力吸収用溝３０、３０によって形成された余剰延伸部Ｓｃによって、引張力が吸収されるので、絵付シートＳｃのうちの製品部１、１に接着付随させるべき部分Ｓａ、Ｓａは製品部から引き剥がされ難くされ、その結果、接着不良や柄抜け等のない良質の製品が得られ、しかも、引張力吸収用溝３０、３０という簡単な構成を付加するだけで済むので、コスト増や作業効率の低下を招くこともない。
【００４２】
【発明の効果】
本発明に係る射出成形同時絵付装置によれば、製品取出時に、絵付シートが製品部から引き剥がす方向に引っ張られることがあっても、絵付シートの製品外部分のうちの引張力吸収用溝によって形成された余剰延伸部によって、引張力が吸収されるので、絵付シートのうちの製品部に接着付随させるべき部分は製品部から引き剥がされ難くされ、その結果、接着不良や柄抜け等のない良質の製品が得られ、しかも、引張力吸収用溝という簡単な構成を付加するだけで済むので、コスト増や作業効率の低下を招くこともない。
【図面の簡単な説明】
【図１】本発明による射出成形同時絵付装置の第１実施形態の雌型を示す平面図。
【図２】図１のＵ−Ｕ矢視線に従う前記装置の射出成形工程時を示す断面図。
【図３】第１実施形態の射出成形工程完了時の状態を示す要部拡大断面図。
【図４】第１実施形態の型開き工程時を示す要部拡大断面図。
【図５】第１実施形態の製品取出工程の説明に供される要部拡大断面図。
【図６】第１実施形態の製品取出工程の説明に供される要部拡大断面図。
【図７】本発明による射出成形同時絵付装置の第２実施形態の射出成形工程時を示す断面図。
【図８】第２実施形態の射出成形工程完了時の状態を示す要部拡大断面図。
【図９】第２実施形態の製品取出工程の説明に供される要部拡大断面図。
【図１０】第２実施形態の製品取出工程の説明に供される要部拡大断面図。
【図１１】従来の射出成形同時絵付装置の一例の雌型を示す平面図。
【図１２】図１１のＶ−Ｖ矢視線に従う前記装置の射出成形工程時を示す断面図。
【図１３】図１１に示される装置の射出成形工程完了時の状態を示す要部拡大断面図。
【図１４】図１１に示される装置の製品取出工程の説明に供される要部拡大断面図。
【図１５】図１１に示される装置の製品取出工程の説明に供される要部拡大断面図。
【図１６】従来の射出成形同時絵付装置の他の例の射出成形工程時を示す断面図。
【図１７】図１６に示される装置の射出成形工程完了時の状態を示す要部拡大断面図。
【図１８】図１６に示される装置の製品取出工程の説明に供される要部拡大断面図。
【図１９】図１６に示される装置の製品取出工程の説明に供される要部拡大断面図。
【符号の説明】
Ｓ絵付シート
Ｓａ製品部に接着付随させるべき部分
Ｓｂ製品外となる部分
Ｓｃ凹字状部
１製品部
９Ｕターン型サブマリンゲート
１０'、４０' 射出成形同時絵付装置
１２、２５雄型
１３、４６ホットランナー
１６、４７ゲート
２５雌型
２７凸状隔壁部
３０引張力吸収用溝[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an injection molding simultaneous painting apparatus in which a picture sheet is integrally bonded to a molded product at the same time as injection molding to obtain a molded product on which a pattern, characters, and the like are applied.
[0002]
[Prior art]
As an injection molding simultaneous painting method in which a picture sheet consisting of a strip sheet or a sheet is supplied between a female mold and a male mold and the picture sheet is integrally bonded to the surface of the molded product at the same time as injection molding, After pre-heating and softening the picture sheet, etc., the sheet is brought into close contact with the cavity of the female mold by vacuum forming and / or pressure forming (preliminary molding step), and then the female mold and the male mold are clamped. The injection molding machine performs injection molding by injecting and filling a resin (melted resin, etc.) in a fluid state from an injection molding machine into the cavity of the female mold through a runner and a gate provided in the male mold. No. 19132, etc.), or without any pre-molding step, the picture sheet is held flat between both male and female molds, and the picture sheet is inserted into the female cavity by the heat and pressure of the resin injected and filled from the male mold side. surface Which adhere to along to and at the same time the surface of the molded product (see JP Kokoku 2-42080) it is common.
[0003]
As a sheet with a picture used for such an injection molding simultaneous picture, either a laminated sheet (laminate sheet) or a transfer sheet is used according to the product type. Painting is performed as it is, and the entire sheet layer is bonded and integrated on the outer surface of the injection-molded product to form a decorative layer. On the other hand, when the picture sheet is a transfer sheet, the support sheet of the decorative sheet integrated on the outer surface of the molded product is peeled off, and the transfer layer such as a decorative layer is left on the molded product side to leave the decorative layer. This completes painting.
[0004]
By the way, in performing the simultaneous injection molding with the above-described injection molding, an injection molding simultaneous painting apparatus having both male and female molds is used. The male mold of the apparatus is provided with a molten resin or the like from an injection molding machine. A cold runner or hot runner is usually provided to fill and fill the female cavity.
However, in the cold runner injection molding simultaneous painting apparatus, it is necessary to move not only the female mold but also the male mold. In other words, it is necessary to move the male mold from the stationary platen to the female mold side in order to remove the cured resin of the runner at the time of taking out the picture molded product, but in a state where the male mold is moved to the female mold 2 side In order to avoid such a problem that the distance between the female mold and the male mold becomes short and the automatic take-out machine cannot be inserted between them, the distance between the female mold and the male mold, that is, the mold It is necessary to increase the opening amount, and the occupied space of the device or the size of the device itself is extremely large as compared with the molded product to be obtained, and the time required for one cycle is increased, which is good in terms of productivity. I could not say it. In addition, the mechanism around the mold is complicated.
[0005]
Therefore, in the injection molding simultaneous painting apparatus, a hot runner type is often used. A typical example of the hot runner type injection molding simultaneous painting apparatus will be briefly described with reference to FIGS. The injection molding simultaneous painting apparatus 40 in the illustrated example moves in a direction (in this case, the Y direction (left-right direction) in FIG. 12), which is a male mold 45 attached to a fixed platen 41, and a direction approaching and separating from the male mold 45. The male mold 45 is fed with a molten resin from a nozzle 70 of an injection molding machine, and is surrounded by a heater 44 made of a heating wire or the like. 46 are provided, and linear columnar gates 47, 47 for injecting the molten resin from the runner 46 to the cavities 26, 26 (two-piece type) of the female die 25 are connected to both ends of the runner 46. It is installed.
[0006]
On the other hand, between the two cavities 26, 26 of the female mold 25 (a central portion), a convex partition wall portion 27 that is outside the product is projected. The female mold 25 is supported by sliding rods 34, 34, 34, 34 at four corners of a rectangular frame or cross-shaped clamper 32 for fixing the picture sheet S to the female parting surface 25a. And can be moved forward and backward. The clamper 32 is operated by a drive mechanism such as a fluid pressure cylinder stored in the bottom of the female die 25. Further, an O-ring 37 is fitted into a part of the female part 25 facing the clamper 32 on the parting surface 25a in order to maintain airtightness.
[0007]
The cavities 26, 26 are provided with vacuum suction holes 36 for extending the painting sheet S along the cavity surface. The vacuum suction holes 36 are formed in the female mold 25. The suction pipe 39 is connected to an external vacuum source via the vacuum suction passage 38 formed.
In addition, in the accompanying drawings (FIGS. 1 to 19) of the present specification, the thickness of the picture sheet S, the hole diameter of the vacuum suction hole 36, etc. are the actual size for easier understanding and for convenience of drawing. It is drawn larger and exaggerated.
[0008]
In the injection molding simultaneous painting apparatus 40, the next shot portion of the painting sheet S is supplied between the parting surface 25a of the female mold 25 and the clamper 32, and this painting sheet S is fed to the party of the female mold 25 by the clamper 32. After being pressed and fixed to the clamping surface 25a, it is heated and softened by a not-shown hot plate or the like, and vacuum suctioned by a vacuum suction means comprising the vacuum suction hole 36 or the like, so that it follows the cavities 26 and 26 of the female die 25. Then, the female mold 25 is moved to the male mold 45 side, and the mold is clamped, and the runner 46 and the gate 47 of the male mold 45 are passed through the cavities 26 and 26 of the female mold 25, respectively. Laminated product 1 in which a melted resin is injected and filled, injection molding is performed, and then the injection-filled resin is cooled and cured (see FIG. 13), and then the sheet S with adhesive is laminated. To take out the 1, performs mold opening to space the female mold 25 and the male 45.
[0009]
With this mold opening, the female mold 25 is separated from the male mold 45 and the molded article (products 1 and 1), and the products 1 and 1 to which the picture sheet S is adhered are attached to the core portion 43 of the male mold 45. Remains. Next, there is a step of taking out the products 1 and 1 remaining in the male mold 45 by ejecting the products 1 and 1 from the male mold 45 side to the female mold 25 side by ejector pins 57 and 57 (see FIG. 14 described later), compressed air or the like. Done.
In this take-out step, the pin-shaped resins 47 and 47 cured by the gates 47 and 47 are taken out as they are attached to the products 1 and 1, so that they are cut out by an appropriate means.
[0010]
However, in such an injection molding simultaneous painting apparatus 40, depending on molding conditions and the like, as shown in FIG. 13, the resin 7 ′ that is cooled and hardened near the tip of the runner 46 (near the rear ends of the gates 47, 47). , 7 'remain, and this cold cured resin residue is injected into the female cavities 26, 26 and applied to the picture sheet S at the time of the next injection molding, resulting in poor adhesion between the picture sheet S and the like. The resulting products 1 and 1 sometimes had poor painting and molding defects such as adhesion failure and pattern (ink) loss.
[0011]
Therefore, the present applicant has first developed an injection molding simultaneous painting apparatus that eliminates the above-mentioned drawbacks, makes it difficult to cause defective molding such as adhesion failure and pattern loss in a molded product, and improves yield and reliability. It has been proposed (see JP-A-9-150433). As shown in FIGS. 16 and 17, the apparatus 10 includes a female mold 25 and a male mold 12 which are basically the same as those shown in FIGS. 11 to 13. A hot runner 13 and columnar gates 16 and 16 (plug portions) surrounded by a heater 14 made of heating wire or the like are provided, and an outward path 9a, an outflow section 9b, and two return paths 9c, A U-turn type submarine gate 9 made of 9c is provided, and the resin sheet 25 in the female mold 25 is brought into close contact with the molten resin from the runner 13 through the forward path 9a and the outflow portion 9b at the tip thereof, but the molten resin is filled. Led out to the convex partition wall portion 27 outside the product, and returned to the columnar gates 16 and 16 through the return paths 9c and 9c so as to draw a U-shape or V-shape therefrom. It is the inside original cavity 26 from the columnar gate 16, 16 so as to inject filling into (product portion 1,1).
[0012]
By doing so, even if the resin 7 ′, 7 ′ that has been cooled and hardened remains in the vicinity of the front end portion of the runner 13, the residue of the resin 7 ′, 7 ′ that has been cooled and hardened remains in the next injection. At the time of molding, the convex partition portion 27 that is outside the product is attached to the picture sheet in the female die 25 but is not filled with the molten resin, standing first through the forward path 9a and the outflow portion 9b of the U-turn type submarine gate 9. And is not captured by the product parts 1 and 1.
[0013]
For this reason, it is possible to make it difficult to cause defective molding with a picture such as adhesion failure or pattern loss in a molded product.
16 and 17, after the male and female molds 12 and 25 are opened, the products 1 and 1 in which the picture sheet S is bonded and laminated on the outer surface are compressed air, ejector pins 57 and the like ( (See FIGS. 18 and 19 to be described later). In this case, the pin-shaped resin 8 cured by the gates 16 and 16 is taken out while being attached to the product 1, and at this time, the pin-shaped resin 8 cured by the gates 16 and 16 and the U-turn portion 9 ( The connecting portion with the hardened resin 7 in the return paths 9c and 9c) is pushed and separated, and the hardened resin 7 in the U-turn portion 9 is ejected from the male mold 25 by the ejector pin 59 or the like when the products 1 and 1 are taken out. Protruded.
[0014]
[Problems to be solved by the invention]
However, the conventional general runner 46 shown in FIGS. 11 to 13 described above, the injection molding simultaneous painting apparatus 40 including the gate 47, and the U-turn type submarine gate 9 shown in FIGS. In the injection molding simultaneous painting apparatus 10 provided, the following problems may occur.
That is, in the apparatus 40 shown in FIGS. 11 to 13, as shown in FIG. 14, the products 1 and 1 attached to the male mold 45 are ejected by the ejector pins 57 and 57 (FIG. 14) or compressed air. An extraction step is performed to remove the male mold 45 from the male mold 45. In this extraction step, the product parts 1 and 1 to which the adhesion-associated portion Sa of the sheet S is usually bonded are ejector pins 57, Projected at 57 mag. The product parts 1 and 1 and the part outside the product (the part Sb outside the product of the sheet S with a picture) are, for example, the part Sb outside the product of the picture sheet S attached to the male mold 45, etc. Due to the fact that the timing at which the outside part Sb is separated from the male mold 45 is delayed (or vice versa) from the timing at which the product parts 1, 1 are ejected from the male mold 45, etc. 14 is pulled away from the products 1 and 1 as indicated by the arrow F in FIG. 14, and as shown in FIG. 15, the adhesion-attached portion Sa of the picture sheet S is separated from the edge portion E of the side end surface 1 a of the product portion 1. It will be peeled off (peeled part Z).
[0015]
When the picture sheet S is peeled off in this way, the obtained product part 1 becomes a picture molding defective product having adhesion failure, pattern loss, or the like.
On the other hand, in the injection molding simultaneous painting apparatus 10 provided with the U-turn type submarine gate 9 shown in FIGS. 16 and 17, the painting sheet S is peeled off for the following reason in addition to the same reason as described above. Is more likely to occur.
That is, as shown in FIG. 18 and FIG. 19, when the product parts 1 and 1 after mold opening are taken out, the product parts 1 and 1 are ejected by the ejector pins 57 and 57 and the U-turn type submarine gate 9 is used. When the cured U-turn portion resin 7 is ejected from the male die 12 by the ejector pin 59, the return passage resin portions 7c and 7c cured in the return passage 9c of the U-turn type submarine gate 9 are narrowed with respect to the protruding direction. Therefore, as the protruding distance increases, it is pushed by the wall surface of the return path 9c to be elastically deformed, and as shown in FIG. 18, it is forced toward the resin part 7a in the forward path that has been cured in the forward path 9a. It can be bent.
[0016]
When the protruding distance further increases, the U-turn portion resin 7 protrudes from the male mold 12 with a slight delay from the product portions 1 and 1, and the pin-shaped resin 8 cured by the gates 16 and 16, Get out of the male mold 12 before 8. In this case, since the in-return resin portion 7c is elastically deformed, when it escapes from the male mold 12, it pops out so as to be repelled by its spring action.
As a result of these actions, when the U-turn part resin 7 adhered to the picture sheet S is protruded from the male mold 12, as shown in FIG. By pulling in the direction, the adhesion-attached portion Sa of the picture sheet S is peeled off from the edge portion E of the side end face 1a of the product portion 1 (peeled portion Z).
[0017]
When the picture sheet S is peeled off in this way, the obtained product becomes a picture molding defective product having adhesion failure, pattern loss or the like.
The present invention has been made to solve the above-described problems. The object of the present invention is to add a relatively simple configuration that does not cause an increase in cost or a decrease in work efficiency, thereby providing a product unit. It is an object of the present invention to provide an injection molding simultaneous painting apparatus in which, even when a picture sheet is pulled in a specific direction, the picture sheet is hardly peeled off from a product part.
[0018]
[Means for Solving the Problems]
In order to achieve the above object, an injection molding simultaneous painting apparatus according to the present invention basically includes a male and female molding die, and the picture sheet supplied on the parting surface of the female mold is clamped by the clamping means. After pressing and fixing on the parting surface, the picture sheet is stretched to adhere along the female mold cavity by a vacuum suction means or the like, and after both the male and female molds are clamped, from the injection molding machine The resin in a fluid state is injected and filled into the cavity of the female mold through a runner and a gate provided in the male mold, and after the resin has solidified, the molds of both the male and female molds are opened. Writing With attached sheet Has a part adhered to the side end face of the solidified resin Adhesive laminated products From both male and female molds To be taken out.
[0019]
And in the part which becomes the product outside in which the said sheet | seat in the said female type | mold is closely_contact | adhered, but the resin of a fluid state is not filled, For forming a surplus stretched part for absorbing tensile force on a picture sheet It is characterized in that a tensile force absorbing groove or projection is formed.
in front Writing The tension absorbing groove or projection is a sheet with a picture. On the side end face of the resin to which Along Side by side The cross-sectional outer shape (cross-section viewed from the direction as shown in FIG. 3) may be any of a rectangle, a rectangle with rounded corners, a semi-ellipse, a semi-circle, a triangle, a W-shape, and the like. However, a rounded shape such as a semicircle or semi-ellipse is preferable in order to effectively exert the tensile force suction effect. In particular, it is preferable that the straight portion of the cross section outside the groove or the convex portion and the straight line or curved portion of the cross section inside the groove or the convex portion are continuously and smoothly connected.
[0020]
In the injection molding simultaneous painting apparatus according to the present invention having such a configuration, the painting sheet is stretched by vacuum suction or the like, and the painting sheet is attached to the outer part of the product (at the time of stretching so as to fit along the female mold cavity). A convex partition wall or the like), and therefore the picture sheet is also in close contact with the tensile force absorbing groove or the convex portion provided in the outer part of the product. Therefore, the extending | stretching part of a cross-sectional concave shape or convex shape is formed in the sheet | seat with a picture according to the cross-sectional shape of the said groove | channel for tensile force absorption, or a convex part, for example.
[0021]
And when taking out a product from a male type (or female type), even if the tensile force of the direction pulled away from a product part acts on a picture sheet, it is formed by the groove | channel or convex part for said tensile force absorption of a picture sheet. For example, an excessively extending portion having a concave or convex cross section develops, the tensile force is absorbed, and a large tensile force does not act on the portion of the picture sheet that should be attached to the product portion.
Therefore, according to the apparatus of the present invention, even when the picture sheet is pulled in the direction of peeling from the product part when the product is taken out, it is formed by the tensile force absorbing groove or the convex part in the outer part of the picture sheet. Since the tensile force is absorbed by the surplus stretched part, the part of the sheet that is to be attached to the product part is difficult to be peeled off from the product part, and as a result, good quality with no adhesion failure or missing pattern In addition, it is only necessary to add a simple structure such as a tensile force absorbing groove or a convex portion, so that there is no increase in cost or reduction in work efficiency.
[0022]
In a preferred embodiment of the present invention, the resin in a fluid state from the injection molding machine is A U-turn type that is provided between the runner and the gate, leads the resin in a fluid state from the runner to a portion outside the product in the female mold, and folds back from there to guide the gate. Led to the female cavity through the gate, more preferably, the front Writing The tension-absorbing groove or convex portion is formed by the product portion into which the fluid resin is injected and filled. The part outside the product in the female mold that leads out the resin with a U-turn type gate Is formed between.
[0023]
In the present invention, the male and female molds may be made of metal such as iron, ceramics, or the like, and may have a divided configuration or the like according to the shape of the molded product. In addition, when pre-forming a picture sheet, a heating plate for heat softening is provided, or a small hole (vacuum suction hole or the like) is used for vacuum suction or pressure air supply (pre-forming) for a female mold and a male mold. ). Alternatively, the female mold may be formed as an aggregate of a plurality of divided parts, and air may be sucked from the gaps between the divided parts. In addition, in the case of a molding shape with small unevenness, preliminary molding can be omitted.
[0024]
The picture sheet may be supplied in a necessary amount (for one shot) from the state of a long continuous belt-like sheet wound up in a roll shape, or a sheet sheet cut in advance to a predetermined size is supplied. You may do it. In addition, in order to supply a belt-like sheet (the next shot part) or a sheet with a picture made of a single-wafer sheet between a female mold and a male mold arranged opposite to each other, the belt-like sheet is used by using an unwinder and a winder. A roll / roll system in which each shot is continuously supplied may be used, or a robot (manipulator) equipped with a suction plate or the like that holds the sheet with the sheet picture may be used. From the aspect, roll / roll method is recommended.
[0025]
In addition, a clamping means may be provided to fix and hold the picture sheet on the female parting surface. As the clamping means, a frame-shaped presser plate or the like can be used, and its driving can be performed using a driving force for molding such as a clamping operation or the power of the ejector pin driving mechanism. Separately, a driving means such as a fluid pressure actuator is provided.
A picture sheet consists of a base sheet and a decorative layer laminated on the base sheet. A laminated sheet (laminate sheet) that is used as a final product while the base sheet is closely integrated with a molded product, or a picture sheet once Any of the transfer sheets that peel off the base sheet (support sheet) leaving only the decorative layer (transfer layer) on the molded product side can be used.
[0026]
As the base sheet, thermoplastic resins such as polyvinyl chloride, acrylic, polystyrene, ABS resin, polycarbonate, polyester, polypropylene, and polyethylene can be used. The thickness of a base material sheet is about 20-500 micrometers normally. As the decorative layer, a printed pattern, coloring or transparent coating, a metal thin film, or a functional layer such as a hard coating film, an antifogging paint, or a conductive layer can be used.
The transfer sheet is for transferring a transfer layer composed of a pattern layer or the like once formed on a peelable support sheet to another transfer target, and is released on the support sheet as necessary. A layer may be provided, and the transfer layer includes a release layer, a decoration layer, an adhesive layer, and the like, and a layer other than the decoration layer is selected as necessary. The decorative layer is selected from a functional layer such as a pattern layer, a metal thin film layer (part or whole surface), a hard coating film, an antifogging coating film, and a conductive layer.
[0027]
The support sheet is preferably a flexible thermoplastic resin film such as polyamide 6 such as nylon 6 or nylon 66, polyolefin such as polyethylene or polypropylene, polyvinyl chloride, or a laminate thereof.
Injection molding resins include ABS (acrylonitrile / butadiene / styrene copolymer) resin, heat-melted thermoplastic resin such as polystyrene, polyvinyl chloride, acrylic, polycarbonate, etc., or two-component curing type, catalyst curing Conventionally known materials can be used for injection-molding simultaneous painting such as uncured liquid such as polyurethane, polyester, etc., depending on the required physical properties and cost of the product.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 to 6 are schematic views showing a first embodiment of an injection molding simultaneous painting apparatus according to the present invention. 1 to 6, parts corresponding to the respective parts in the injection molding simultaneous painting apparatus 40 shown in FIGS. 11 to 15 described above are denoted by the same reference numerals, and redundant description thereof will be omitted. Explain the point with emphasis.
[0029]
In the injection molding simultaneous painting apparatus 40 ′ of the illustrated embodiment, the convex partition 27, which is the part outside the product in which the picture sheet S is in close contact with the female mold 25 but is not filled with the molten resin, has a rounded rectangular shape. The tensile force absorbing grooves 30 and 30 are formed. The tensile force absorbing grooves 30 and 30 are formed in the cavities 26 and 26, respectively, in the convex partition walls 27 near the two cavities 26 and 26 for taking two products. The product parts 1 and 1 are arranged side by side in parallel along the opposing side end faces 1a and 1a (parts where the picture sheet S is easily peeled off). In other words, the tensile force absorbing grooves 30 and 30 are arranged along a direction orthogonal to the direction of peeling off the portion of the picture sheet S to be attached to the product portion. The portion of the male mold 45 facing the tensile force absorbing grooves 30 and 30 may be a flat surface, or may be a convex portion that is housed and fitted in the groove.
[0030]
The product 1 to be obtained by the injection molding simultaneous painting apparatus 40 ′ of the present embodiment is a curved elongated panel having a width of 30 to 80 mm and a length of 300 to 400 mm. You can take two products.
Further, here, as the sheet S with a picture, a base sheet made of acrylic resin (thickness is 125 μm) and a decorative layer (1 of acrylic resin and vinyl chloride vinyl acetate copolymer) laminated thereon by gravure printing method. 1: a paint layer made of ink consisting of a resin binder and pigment in a weight ratio mixture) and an adhesive layer (vinyl chloride vinyl acetate copolymer system). A laminated laminate sheet (laminate sheet) that is used as a final product is used. The decorative layer (pattern layer) has a wood grain pattern combining three colors of pattern plates, and the adhesive layer is a gravure solid printing plate having a screen line number of 40 lines / cm (plate depth 60 μm). This is a layer having a thickness of 2 μm formed using two times (by gravure printing two colors).
[0031]
In the injection molding simultaneous painting apparatus 40 ′ of the present embodiment configured as described above, vacuum suction through the vacuum suction hole 37 and the like in a state in which the picture sheet S is heated and softened by a heating plate or the like (not shown). At the time of the stretching process in which the sheet S is stretched and closely adhered to the female cavity 26, the picture sheet S is also adhered to the outside part of the product (convex partition part 27), and is provided on the outside part of the product. The picture sheet S is also in close contact with the tensile force absorbing grooves 30, 30. Therefore, a surplus extending portion Sc having a concave cross section corresponding to the cross sectional shape of the tensile force absorbing grooves 30 and 30 is formed in the product outer portion Sb of the picture sheet S.
[0032]
After the stretching process, the female mold 25 is moved to the male mold 45 side to perform clamping, and molten resin is injected and filled into the cavities 26 and 26 of the female mold 25 through the runner 46 and the gate 47 of the male mold 45, respectively. Then, injection molding is performed, and after the filled resin is cooled and hardened, the female mold 25 is moved away from the male mold 25 to open the mold as shown in FIG. By this mold opening, the female mold 25 is separated from the product parts 1 and 1 on which the male mold 45 and the picture sheet S are adhesively laminated, and the product parts 1 and 1 on which the picture sheet S is adhesively laminated are the core part of the male mold 45. It remains attached to 43 (see FIG. 4). Next, an extraction process is performed in which the product parts 1 and 1 remaining on the male mold 45 are ejected from the male mold 45 side to the female mold 25 side by ejector pins 57 and 57 (FIG. 5) or compressed air, for example. .
[0033]
In this extraction step, as shown in FIGS. 5 and 6, when the product parts 1, 1 are pushed out from the male mold 45, the tensile force in the direction in which the adhesion-attached portion Sa of the picture sheet S is separated from the side end face 1 a of the product 1. Even if (arrow F in FIG. 5) acts, the excessively extending portion Sc having a concave cross section formed in the outer portion Sb of the product sheet S by the tensile force absorbing grooves 30, 30 is developed. The tensile force is absorbed, and the large tensile force does not act on the portion Sa of the picture sheet S to be attached to the product portion 1.
[0034]
Therefore, according to the apparatus 40 ′ of the present embodiment, even when the product sheet 1 is pulled in the direction of peeling from the product parts 1 and 1 when the product is taken out, Since the tensile force is absorbed by the excess stretched portion Sc formed by the tensile force absorbing grooves 30, 30, the portions Sa, Sa to be attached to the product portions 1, 1 of the picture sheet S are attached from the product portion. As a result, it is difficult to peel off, and as a result, a high-quality product with no adhesion failure or pattern omission is obtained, and it is only necessary to add a simple structure of the tensile force absorbing grooves 30 and 30 to increase costs and work. There is no loss of efficiency.
[0035]
In addition, it may replace with the said tension | pulling force absorption groove | channel 30, and you may provide the convex part (projection) for tensile force absorption, and in this case, the concave groove in which the said convex part is accommodated is formed in the male type | mold side. .
7-10 is schematic which shows 2nd Embodiment of the injection molding simultaneous painting apparatus based on this invention. 7 to 10, portions corresponding to the respective portions in the injection molding simultaneous painting apparatus 10 shown in FIGS. 16 to 19 described above are denoted by the same reference numerals, and redundant description thereof is omitted. Explain the point with emphasis.
[0036]
Also in the injection molding simultaneous painting apparatus 10 ′ of the illustrated embodiment, similar to the first embodiment, the convex shape which is a part outside the product in the female mold 25 where the painting sheet S is adhered but the molten resin is not filled. Tensile force absorbing grooves 30, 30 having a rounded rectangular cross section are formed in the partition wall portion 27. The tensile force absorbing grooves 30 and 30 are formed in the cavities 26 and 26, respectively, in the convex partition walls 27 near the two cavities 26 and 26 for taking two products. The product parts 1 and 1 are arranged side by side in parallel along the opposing side end faces 1a and 1a (parts where the picture sheet S is easily peeled off). In other words, the tensile force absorbing grooves 30 and 30 are arranged along a direction orthogonal to the direction of peeling off the part of the picture sheet S to be attached to the product part, and the other configurations are as follows: This is the same as that shown in FIGS.
[0037]
In the apparatus 10 ′ of the present embodiment, a hot runner 13 and columnar gates 16 and 16 (plug portions) are provided, and between them, an outward path 9a, an outflow section 9b, and two return paths 9c and 9c. Become U-turn type gate A U-turn type submarine gate 9 is provided, and the resin sheet 25 in the female mold 25 is brought into close contact with the molten resin from the runner 13 through the forward path 9a and the outflow portion 9b at the tip thereof, but the molten resin is not filled. And is led back to the columnar gates 16 and 16 through the return paths 9c and 9c so as to draw a U-shape or V-shape. 26 and 26 (product parts 1 and 1) are injected and filled, so that even if the resin 7 'and 7' that has been cooled and hardened remain in the vicinity of the tip of the runner 13, it is cooled and hardened. Residues of the resin 7 'and 7' left at the head through the forward path 9a and the outflow part 9b of the U-turn type submarine gate 9 in the next injection molding, The picture sheet in FIG. 5 is in close contact but is not filled with the molten resin, and is led out and captured by the convex partition wall 27 outside the product, and is not led to the product parts 1 and 1.
[0038]
Also in the apparatus of the present embodiment, the picture sheet S is stretched by vacuum suction through the vacuum suction hole 36 or the like while being heated and softened by a heating plate or the like (not shown) so as to be along the female cavity 26. During the drawing process, the picture sheet S is also in close contact with the outer part of the product (the convex partition wall 27), and the tensile force absorbing grooves 30 and 30 provided in the outer part of the product are also provided with the picture sheet. S adheres. Therefore, a surplus extending portion Sc having a concave cross section corresponding to the cross sectional shape of the tensile force absorbing grooves 30 and 30 is formed in the product outer portion Sb of the picture sheet S.
[0039]
After the stretching process, the female mold 25 is moved to the male mold 12 side to perform clamping, and the molten resin is passed through the runner 13 of the male mold 12 and the U-turn type submarine gate 9 into the cavities 26 and 26 of the female mold 25, respectively. Is injected and filled, and injection molding is performed. After the filled resin is cooled and hardened, the female mold 25 is moved away from the male mold 12 to open the mold as shown in FIG. With this mold opening, the female mold 25 is separated from the product parts 1 and 1 on which the male mold 12 and the picture sheet S are adhered and laminated, and the product parts 1 and 1 on which the picture sheet S is adhered and laminated are the core parts of the male mold 12. 19 remains attached. Next, the product parts 1 and 1 remaining in the male mold 15 are ejected from the male mold 12 by the ejector pins 57 and 57, and the U-turn part resin 7 cured by the U-turn type submarine gate 9 is ejected from the male mold 12 by the ejector pin 59. Stick out. At this time, since the return path resin portions 7c and 7c cured in the return path 9c of the U-turn type submarine gate 9 are inclined so that the return path 9 is narrowed with respect to the protruding direction, the protruding distance increases. As shown in FIG. 9, the return path 9c is pushed by the wall surface of the return path 9c to be elastically deformed, and is forcibly bent toward the outward path resin portion 7a cured by the forward path 9a.
[0040]
When the protruding distance further increases, the U-turn portion resin 7 protrudes from the male mold 12 with a slight delay from the product portions 1 and 1, and the pin-shaped resin 8 cured by the gates 16 and 16, Get out of the male mold 12 before 8. In this case, since the in-return resin portion 7c is elastically deformed, when it escapes from the male mold 12, it pops out so as to be repelled by its spring action.
As a result of these actions, when the U-turn part resin 7 stuck to the picture sheet S is protruded from the male mold 12, as shown in FIG. 10, the product outer portion Sb of the picture sheet S is moved in the direction of arrow F in the figure. Pull on.
[0041]
Here, in the present embodiment, even if the tensile force in the direction of separating from the product portion 1 as described above acts on the picture sheet S, the portion outside the product is caused by the tensile force absorbing grooves 30 and 30 in the picture sheet S. The excessively extending portion Sc having a concave cross section formed in Sb is developed, the tensile force is absorbed, and a large tensile force does not act on the portion Sa of the picture sheet S to be attached to the product portion 1. .
Therefore, even in the apparatus 10 ′ of the present embodiment, even if the picture sheet S may be pulled in the direction of peeling from the product parts 1 and 1 when the product is taken out, the tension of the outside part Sb of the picture sheet S is pulled. Since the tensile force is absorbed by the surplus stretched portion Sc formed by the force absorbing grooves 30, 30, the portions Sa, Sa to be attached to the product portions 1, 1 of the picture sheet Sc are pulled from the product portion. As a result, it is difficult to peel off, and as a result, it is possible to obtain a high-quality product with no adhesion failure or pattern omission, and it is only necessary to add a simple structure of the tensile force absorbing grooves 30 and 30 to increase costs and work efficiency. It does not lead to a decrease in.
[0042]
【The invention's effect】
According to the injection molding simultaneous painting apparatus according to the present invention, even if the picture sheet is pulled in the direction of peeling from the product part at the time of product removal, the tensile force absorbing groove in the outer part of the picture sheet is used. Since the tensile force is absorbed by the formed surplus stretched portion, the portion of the picture sheet that should be attached to the product portion is hardly peeled off from the product portion, and as a result, there is no adhesion failure or pattern loss. A high-quality product can be obtained, and furthermore, it is only necessary to add a simple structure of a tensile force absorbing groove, so there is no increase in cost and reduction in work efficiency.
[Brief description of the drawings]
FIG. 1 is a plan view showing a female mold of a first embodiment of an injection molding simultaneous painting apparatus according to the present invention.
FIG. 2 is a cross-sectional view showing an injection molding process of the apparatus according to the line U-U in FIG.
FIG. 3 is an enlarged cross-sectional view of a main part showing a state when an injection molding process according to the first embodiment is completed.
FIG. 4 is an enlarged cross-sectional view of a main part showing a mold opening process of the first embodiment.
FIG. 5 is an enlarged cross-sectional view of a main part for explaining a product take-out process according to the first embodiment.
FIG. 6 is an enlarged cross-sectional view of a main part for explaining a product take-out process according to the first embodiment.
FIG. 7 is a cross-sectional view showing the injection molding step of the second embodiment of the simultaneous injection molding device according to the present invention.
FIG. 8 is an enlarged cross-sectional view of a main part showing a state at the completion of an injection molding process of the second embodiment.
FIG. 9 is an enlarged cross-sectional view of a main part provided for explaining a product take-out process according to the second embodiment.
FIG. 10 is an enlarged cross-sectional view of a main part provided for explaining a product take-out process according to a second embodiment.
FIG. 11 is a plan view showing a female mold of an example of a conventional injection molding simultaneous painting apparatus.
12 is a cross-sectional view showing an injection molding process of the device according to the line VV in FIG.
13 is an enlarged cross-sectional view of a main part showing a state when the injection molding process of the apparatus shown in FIG. 11 is completed.
14 is an enlarged cross-sectional view of a main part provided for explaining a product take-out process of the apparatus shown in FIG.
FIG. 15 is an enlarged cross-sectional view of a main part for explaining a product take-out process of the apparatus shown in FIG. 11;
FIG. 16 is a sectional view showing another example of the conventional injection molding simultaneous painting apparatus in the injection molding process.
17 is an enlarged cross-sectional view of a main part showing a state when the injection molding process of the apparatus shown in FIG. 16 is completed.
18 is an enlarged cross-sectional view of an essential part for explaining a product take-out process of the apparatus shown in FIG.
FIG. 19 is an enlarged cross-sectional view of a main part provided for explaining a product removal process of the apparatus shown in FIG. 16;
[Explanation of symbols]
S picture sheet
Sa Parts to be attached to the product part
Parts that are outside the Sb product
Sc Concave part
1 Product Department
9 U-turn type submarine gate
10 ', 40' simultaneous injection molding equipment
12, 25 male
13, 46 Hot runner
16, 47 gate
25 female
27 Convex partition
30 Groove for absorbing tensile force

Claims

A male and female molding die, and a picture sheet supplied on the parting surface of the female mold is pressed and fixed on the parting surface by a clamping means, and then the picture sheet is placed in the female mold cavity by a vacuum suction means or the like. The mold is stretched so as to be in close contact with each other, and after both the male and female molds are clamped, the resin in a fluid state from the injection molding machine is injected into the cavity of the female mold through a runner and a gate provided in the male mold. filled, after the resin has solidified, the performing mold opening of the male and female molds, before disappeared with sheets, adhesive laminated laminated product having an adhesive portion on a side end face of the solidified resin In the injection molding simultaneous painting apparatus configured to take out from both the male and female molds ,
Tensile force absorbing grooves or protrusions for forming an extra stretched portion for absorbing tensile force on the painted sheet on the outer portion of the female mold where the painted sheet is in close contact but is not filled with resin in a fluid state An injection molding simultaneous painting apparatus characterized in that is formed.

The resin in a fluid state from the injection molding machine is provided between the runner and the gate, and the resin in a fluid state from the runner is led out to a portion outside the product in the female mold and folded from there. 2. The injection molding simultaneous painting apparatus according to claim 1, wherein the apparatus is guided to the female cavity through a U-turn type gate that leads to the gate.

Before Ki引 tension absorbing groove or convex portion is formed between the product out to become part of the female mold resin in the fluidized state derives the resin in the U-turn of the gate and the product part to be injected and filled The simultaneous injection-molding apparatus with injection molding according to claim 2.

The tension absorbing groove or convex portion is injection molded according to any one of claims 1 to 3, characterized in that the decorative sheet is arranged along the side end face of the resin are bonded Simultaneous painting device.