JP4014232B2 - Electromagnetic induction heating mold for resin molding - Google Patents
Electromagnetic induction heating mold for resin molding Download PDFInfo
- Publication number
- JP4014232B2 JP4014232B2 JP18222694A JP18222694A JP4014232B2 JP 4014232 B2 JP4014232 B2 JP 4014232B2 JP 18222694 A JP18222694 A JP 18222694A JP 18222694 A JP18222694 A JP 18222694A JP 4014232 B2 JP4014232 B2 JP 4014232B2
- Authority
- JP
- Japan
- Prior art keywords
- mold
- metal layer
- induction heating
- electromagnetic induction
- alloy
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Landscapes
- Moulds For Moulding Plastics Or The Like (AREA)
Description
【０００１】
【産業上の利用分野】
この発明は射出成形、圧縮成形、ブロー成形など原料プラスチックを投入した後、熱の授受によって賦型、固化させる樹脂成形用金型に関する。特に、金型表面の光沢や、模様を忠実に賦型して外観良好な成型品を得るために１サイクル内に金型表面および金型本体温度を外部からの電力熱を用い上下させる成型法に使用する金型に関する。
【０００２】
【従来の技術】
プラスチックの成形は、射出成形、圧縮成形、ブロー成形など原料プラスチックを投入した後、熱の授受を行って、プラスチックを賦型、固化させる。このような金型の具備すべき一般的要件は、表面が充分な硬さを有し、構造的に充分な強さを有し、なおかつ熱の授受が効率よく行われることである。即ち、製品の成形サイクル時間が短縮され、成形効率が改善されると共にヒ−トクラックの発生、進展を押さえ金型寿命の向上が望まれている。更には、成形品質の改善、特に表面光沢や仕上がり精度、金型表面の忠実な転写精度に対する要求が求められる様になった。
【０００３】
すなわち、原料投入工程では原料プラスチックが流動するに適した温度が維持でき、固化工程ではプラスチックとの間で熱の授受が速やかに行われることが求められており、一般の成形においては、冷却時間が全工程の過半を占め、金型内のプラスチックとの熱の授受の速さが生産性に大きく影響してくる。熱の授受が高速に行われるために第一に必要なことは、金型素材の熱伝導度が高いことである。さらに金型内のプラスチックと熱交換を行う部分の熱慣性が小さいことが好ましい。加熱または冷却を熱媒で行うにせよ、金型自体の熱慣性が小さければ、プラスチックからの熱量を取りやすく、熱交換率は高くなる。さらに付け加えれば、効率のよい加熱または冷却、あるいは双方の手段を有することが望ましい。
【０００４】
この他、金型表面にキズが付くと成形不良につながるため金型表面は硬度が高く、キズが付きにくいことが必要である。さらに金型全体の構造が機械的に充分な強度を有することが必要なのは言うまでもない。
【０００５】
特に近年、成形サイクルの向上と平行して、成形品の表面仕上げ精度に対する品質の向上を要求されるようになり、金型キャビテイー表面（金型作業面最表層）のみを部分加熱する新しい技術として、高周波電磁誘導加熱式射出成形金型が開発された。
【０００６】
この高周波電磁誘導加熱式射出成形金型とは、キヤビティー表面局部加熱型の成形金型で、金型のキャビティー表面のみを誘導加熱により選択的に急速昇温し、樹脂充填時のみ高温金型の状態を作り出す成形金型で、通常の成形金型では得られない高い金型温度での成形を、生産性を大幅に損なうことなく可能にする金型である。
【０００７】
この高周波電磁誘導加熱式射出成形金型を用いた射出成形方法や射出成型物については、例えば、特公昭５８−４０５０４号、昭６０−５６６０４号、などに開示されており、成型品に充填材が入った場合でも入らない場合でも全く同じ様にジェッティング、フローマーク、ウエルドライン等の欠点や射出成型機のゲート部付近と樹脂流動末端（デッドエンド）部の光沢差（光沢班）のない成型品が得られる、特に充填材が入った場合に充填材の現出も無くなる。また、平滑でない表面、例えば粗い凹凸模様、シボ、梨地（すりガラス状）等を有する成形体を得る場合でも、転写性が優れているので極めて良好な外観を得ることが出来る。ところが、これら前記電磁誘導加熱方法での金型は金型本体が鍛造鋼、鋳鉄などの単一金属であるので、金型キャビティー表面のみを選択的に高温加熱しようとしてもキャビティー表面の形状に起因する局部的発熱による不均一な温度上昇や、熱伝導性が低い事などによってかなりの熱損失及び電磁損があつた。
【０００８】
更に、加熱時には電磁誘導加熱によって金型内部温度が上昇しないのと同様に冷媒による強制冷却過程においても、鉄などの単一金属では熱伝導が小さいため、冷媒の冷却効果をキャビティー表面、即ち、成型品自身に伝達するのに時間を要し、且つ複雑な凹凸面を有するキャビティー表面では、均一な冷却を得るのに更に時間を必要としていた。
【０００９】
【発明が解決しようとしている課題】
本発明はかかる問題に着目して成されたものである。その目的は型構造材料としての高強度を有し、かつ、高熱伝導度、耐熱慣性を備え、大幅な成形サイクルの短縮、成形効率の向上が図れるとともに、金型表面の光沢や模様を忠実に賦型して外観良好な高品質成型品を得るための樹脂成形用電磁誘導加熱式金型を提供するにある。
【００１０】
【課題を解決するための手段】
本発明者は、鋭意検討した結果、電磁誘導加熱式の金型を爆発圧着により冶金的に接合した高熱伝導性金属層と磁性金属層との複合層から構成することが有効であることを見出し、本発明に至った。すなわち、本発明は、アルミニウム、アルミニウム合金、銅、銅合金より選択される高熱伝導性金属層とニッケル、ニッケル合金、鉄、鉄合金から選択される磁性金属層とが爆発圧着により冶金的に接合された少なくとも２層以上の複合層からなる樹脂成形用電磁誘導加熱式金型であって、前記磁性金属層表面にキャビティー面が形成されることを特徴とする樹脂成形用電磁誘導加熱式金型に関する。
【００１１】
高周波電磁誘導加熱式射出成形では、金型キャビティーの表面付近のみ急速加熱・昇温して、高温状態のキヤビティーに樹脂を射出し、水などの媒体を用い樹脂を冷却する成型法で、この場合の金型昇温の手段としては、数秒程度の短時間で金型表面温度を昇温するために、加熱には誘導加熱方式が使用される。
【００１２】
誘導加熱とは、加熱する金属片を周期的に変動する磁界中に置き、金属内に発生する渦電流によって、金属片自身を発熱させるもので、金属の表面付近のみ発熱し、大きな発熱量が得られることが特徴である。
【００１３】
この誘導加熱方式を採用した射出成形方法としては、インダクタを金型の間に挟み込んで、高周波発信器で誘導加熱する方式と、インダクタをキャビティーの裏側に内蔵する方式の２種類があり、成型品の形状、構造、材質などによって使い分けられている。
【００１４】
しかし、いづれの方式であっても、インダクタに隣接する金型の被加熱金属層は磁性金属層、特に強磁性金属層で有ることが好ましく、発熱効率が良いので急速昇温が得られる。
【００１５】
次に、樹脂充填後は、高温加熱したキャビティー表面金属層及び、成形金型全体を急速に冷却しなければならず、この為には成形金型は冷却水や冷媒の熱伝導性に優れていること、即ち、熱の授受が効率よく行われ、かつまた、構造的に充分な高剛性を有していることが好ましい。
【００１６】
また本発明の樹脂成型用金型によれば、高熱伝導性で、好ましくはかつ低体積比熱金属層を有する複合金属層で形成されているため、あるいはまた、金型をインダクタや冷媒によって加熱、冷却する金属層を高熱伝導性で、好ましくはかつ低体積比熱金属層で形成されているため金型の熱慣性が小さく、誘導加熱を併用した場合の金型は１サイクル内に効率的に加熱冷却することができる。
【００１７】
即ち、本発明は電磁誘導加熱等の強制加熱及び、冷媒などによる強制冷却を行う樹脂成形金型において熱交換効率を高めることによって、製品の成形サイクル時間が短縮され、成形効率が良く、ヒ−トクラックの発生進展を押さえた高寿命金型であり、また、成形品質の改善、特に表面光沢や仕上り精度、金型表面の忠実な転写精度を有する金型である。
【００１８】
本発明の樹脂成形用金型は、その構成材料が高熱伝導性で、好ましくはかつ低体積比熱金属層と磁性金属層との冶金的接合による複合層から少なくともなるものである。また、本発明の金型は、好ましくは金型ないしは金型部品に充分な剛性、強度を付与するため、高剛性を有する材料を金型基材（強度部材）層に冶金的に接合することもできる。また、この金型基材層を磁性金属層で兼ねさせることもできる。
【００１９】
この発明で言う金型基材となる高剛性金属は一般構造用圧延鋼、機械構造用炭素鋼、構造用合金鋼、炭素工具鋼、軸受け鋼等の鉄鋼、ステンレス鋼その他強度の高い金属であり、高熱伝導性で好ましくはかつ低体積比熱金属材料はアルミニウム、アルミニウム合金、銅、銅合金等である。
【００２０】
ここで、体積比熱（Ｃａｌ・ｄｅｇ~1・Ｃｍ~3）は、
比熱（Ｃａｌ・ｄｅｇ~1・ｇ~1）ｘ密度（ｇ・Ｃｍ~3）の事であり、金型などの伝熱は全て体積あたりの比熱で考えることから、このような言い方をする。
【００２１】
また、磁性金属材料はニッケル、ニッケル合金、鉄、鉄合金等である。
【００２２】
また、本発明の金型は、金型全体の熱慣性を小さくし、成形サイクルを向上するために、金型基材を低熱伝導性材料から構成するか、または、金型基材と高熱伝導性で、好ましくはかつ低体積比熱金属層の間に低熱伝導性の接合金属材料層を設け、冶金的に接合できる。この低熱伝導性の金属材料は、ステンレス鋼、チタン、チタン合金、ジルコニウム、ジルコニウム合金等の低熱伝導の材料である。
【００２３】
またさらに、金型の成形サイクルを向上するための冷熱媒流路形成のため高熱伝導性で、好ましくはかつ低体積比熱金属層の内部に孔を設けるか、あるいは、この高熱伝導性金属層とそれに接する基材層やキャビティ表面層を構成する金属材料との接合面に溝を設けることができる。
【００２４】
高熱伝導性で好ましくはかつ低体積比熱金属層は、厚くすると熱伝導は良くなる。また、薄くすると熱慣性を軽減することができる。このため、この層の厚みは金型の構造によって最適値が異なる。熱交換が十分出来る系や大型成形品あるいは形状が複雑で型表面の温度がバラツキ易い金型では２０ｍｍ以上と厚めにするとよい。小型用や原料投入時と冷却時の温度差を付けたい場合は５ｍｍ〜２０ｍｍ程度にする。
【００２５】
熱交換用に設ける孔ないし溝は、水、油などの熱媒循環用、あるいはヒートパイプ、電気ヒータを装着する。なお、この孔ないし溝は、高熱伝導性かつ低体積比熱金属層の熱伝導面積を減らす効果もあり、低熱伝導金属層または金型基材以降への伝熱を小さくする。
【００２６】
本発明で言う冶金的接合とは２つの金属を原子間引力が作用する領域まで近づけ接合せしめたものであり、通常、摩擦圧着、爆発圧着、ロール圧着、拡散接合、電気メッキ等の手段により接合する。また、２つの異なる金属を冶金的に直接接合することが難しい場合には中間材として、例えば、純アルミニウム、チタン、ニッケル、純鉄、銅、銀、またはこれらを主成分とするロウ材等を用い接合せしめることができる。本発明においては、このように冶金的接合により複合したことにより、通常の嵌合によるものに比べて熱伝導性をさらに向上することができる。
【００２７】
【実施例】
実施例１
図面を参照して説明すると、図１は射出成型用の本発明の樹脂成形金型（下型）の層構成を示す側断面図である（ただし、層構成の同じ上型は図示せず）。
【００２８】
この金型の材料は、厚さ５０ｍｍの金型鋼材からなる金型基材層１、厚さ２０ｍｍのアルミニウム合金からなる高熱伝導性かつ低体積比熱金属層２、厚さ１ｍｍのニッケル合金からなる磁性金属層３が爆発圧着法によって冶金的に接合されたクラッド金属板であり、アルミニウム合金部分には冷却性を向上するために水冷孔５が設けて有る。また、キャビティ面はニッケル合金磁性金属層となる。
【００２９】
この樹脂成型用金型のニッケル合金表面側キャビティ面にインダクター６を図示しない上型ではさむように配置して高周波電磁誘導加熱によりキャビティ面を加熱した後、インダクタ６を除き、ガラス繊維が充填された樹脂を用いて射出成形を行ったところ、従来の金型に較べて昇温、冷却速度が速く、加熱ムラが少ないことから表面肌の美麗な成型品が得られた。
【００３０】
比較例１
図面を参照して説明すると、図２は本発明金型と比較する為に製作した射出成型用の樹脂成形金型（下型）の層構成を示す側断面図である（ただし、層構成の同じ上型は図示せず）。
【００３１】
この金型の材料は、厚さ７１ｍｍの金型鋼材からなる金型基材１の単一金属であり、実施例１と同位置に冷却性を向上するための水冷孔５が設けて有る。
【００３２】
この樹脂成型用金型の表面側に実施例１と同様にしてインダクタ６を配置して高周波電磁誘導加熱によりキャビティ面を加熱した後、実施例１と同一材料、同一条件でガラス繊維が充填された樹脂を用いて射出成形した。
【００３３】
上記実施例１と比較例１の形成結果の比較では、比較例１に較べて、実施例１がアルミニュウム合金の厚さ２０ｍｍと、ニッケル合金厚さ１ｍｍ合計分の体積比熱差分の昇温、冷却速度が速く加熱ムラが少ないことが判った。
【００４０】
【発明の効果】
本発明の成形金型は構造材料としての高強度を有しかつ、高熱伝導度、耐熱慣性を備え、大幅な成形サイクルの短縮、成形効率の改善、熱効率の向上が図れると共に、金型表面の光沢や模様を忠実に賦型して外観良好な高品質成型品を得るための樹脂成形用金型を提供することができる。
【００４１】
また、ガラス繊維や無機物、金属粉等を充填材とした各種充填材入り熱可塑性樹脂成形を行った場合には、成型品表面に充填材が露出せず、換言すれば熱可塑性樹脂の薄膜表皮層が形成でき、充填材で補強した樹脂でも非補強樹脂と同等の表面状態が得られ、難成形（高粘度、高融点）樹脂の転写性が改善される。しかも、ジェッティング、フローマーク、ウエルドラインなどの表面不良の発生防止もできる。
【００４２】
さらに、流動性の向上により、高粘度、高融点樹脂の成形性が向上する。また、このほか、成型品の内部応力及び後収縮を減少させる事が出来る。
【００４３】
以上の事により、結果として、例えばＰＭＭＡ樹脂製カーステレオ全面パネルではウエルドライン消しによる高品質化、ＨＩＰＳ樹脂製小型ＴＶ全面パネルでは、ウエルドライン消し、塗装の省力化、ＡＢＳ樹脂製ハンドシャーワー穴板では、ウエルドライン消しによる孔明け工程省略、ＡＢＳGF樹脂製化粧品容器等では、樹脂の剛性を生かした薄肉化、塗装の省略が可能となった。
【図面の簡単な説明】
【図１】 図１は本発明の樹脂成形金型（下型）の層構成を示す側断面図である。
【図２】 図２は実施例１に示す本発明金型と比較するための射出成型用の樹脂成形金型（下型）の層構成を示す側断面図である。この金型は、金型鋼材で製作した基材金属層のみの単一金属金型である。
【符合の説明】
１：基材金属層
２：高熱伝導性かつ低体積比熱金属層
３：磁性金属層
４：低熱伝導性金属層
５：冷却孔
６：インダクタ[0001]
[Industrial application fields]
The present invention relates to a mold for resin molding in which raw material plastic such as injection molding, compression molding, blow molding, and the like is molded and solidified by heat transfer. In particular, a molding method in which the mold surface and the mold body temperature are raised and lowered using external power heat within one cycle in order to obtain a molded product with a good appearance by faithfully shaping the gloss and pattern of the mold surface. It relates to the mold used for
[0002]
[Prior art]
For plastic molding, raw material plastic such as injection molding, compression molding, blow molding, etc. is introduced, and then heat is transferred to shape and solidify the plastic. The general requirements to be possessed by such a mold are that the surface has sufficient hardness, has sufficient structural strength, and heat is efficiently transferred. That is, it is desired that the molding cycle time of the product is shortened, the molding efficiency is improved, the generation and progress of heat cracks are suppressed, and the die life is improved. Furthermore, there has been a demand for improvements in molding quality, particularly surface gloss and finishing accuracy, and faithful transfer accuracy on the mold surface.
[0003]
That is, it is required that the temperature suitable for the flow of the raw material plastic can be maintained in the raw material charging process, and that heat is quickly exchanged with the plastic in the solidification process. In general molding, cooling time is required. Occupies the majority of all processes, and the speed of heat exchange with plastic in the mold greatly affects productivity. The first requirement for heat transfer at high speed is that the mold material has high thermal conductivity. Furthermore, it is preferable that the thermal inertia of the portion that exchanges heat with the plastic in the mold is small. Even if heating or cooling is performed with a heat medium, if the thermal inertia of the mold itself is small, the amount of heat from the plastic can be easily taken and the heat exchange rate becomes high. In addition, it is desirable to have efficient heating and / or cooling means.
[0004]
In addition, if the surface of the mold is scratched, it leads to molding failure, so that the surface of the mold must have high hardness and be difficult to be scratched. Needless to say, the structure of the entire mold must have sufficient mechanical strength.
[0005]
In recent years, in parallel with the improvement of the molding cycle, it has become necessary to improve the quality of the surface finish accuracy of molded products, and as a new technology that only partially heats the mold cavity surface (the outermost layer of the mold work surface) High frequency electromagnetic induction heating type injection mold was developed.
[0006]
This high-frequency electromagnetic induction heating type injection mold is a mold with a cavity surface local heating type, and only the cavity surface of the mold is selectively heated rapidly by induction heating, and the high-temperature mold only when filled with resin. This is a mold that makes it possible to perform molding at a high mold temperature, which is not possible with a normal mold, without significantly impairing productivity.
[0007]
The injection molding method and the injection molded product using this high frequency electromagnetic induction heating type injection mold are disclosed in, for example, Japanese Patent Publication Nos. 58-40504 and 60-56604, and the like. In the same or no case, there are no defects such as jetting, flow marks, and weld lines, and there is no difference in gloss between the gate part of the injection molding machine and the resin flow end (dead end). A molded product can be obtained, especially when a filler is contained, and the appearance of the filler is eliminated. Even when a molded body having a non-smooth surface, for example, a rough concavo-convex pattern, texture, satin (ground glass) or the like is obtained, a very good appearance can be obtained because of excellent transferability. However, since the mold body in the electromagnetic induction heating method is a single metal such as forged steel or cast iron, the shape of the cavity surface is selected even if only the mold cavity surface is selectively heated at a high temperature. There was considerable heat loss and electromagnetic loss due to non-uniform temperature rise due to local heat generation due to, and low thermal conductivity.
[0008]
Furthermore, in the forced cooling process by the refrigerant as well as the temperature inside the mold does not increase due to electromagnetic induction heating at the time of heating, since the single metal such as iron has a small heat conduction, the cooling effect of the refrigerant is reduced to the cavity surface, that is, However, it takes time to transmit to the molded product itself, and the cavity surface having a complex uneven surface requires more time to obtain uniform cooling.
[0009]
[Problems to be solved by the invention]
The present invention has been made paying attention to such a problem. Its purpose is to provide high strength as a mold structure material, high thermal conductivity and heat inertia, greatly shortening the molding cycle and improving molding efficiency, and faithful to the gloss and pattern on the mold surface. An object of the present invention is to provide an electromagnetic induction heating mold for resin molding for shaping and obtaining a high-quality molded product having a good appearance.
[0010]
[Means for Solving the Problems]
As a result of intensive studies, the present inventor has found that it is effective to form a composite layer of a highly thermally conductive metal layer and a magnetic metal layer obtained by metallurgically joining an electromagnetic induction heating type metal mold by explosive pressure bonding. The present invention has been reached. That is, according to the present invention, a highly thermally conductive metal layer selected from aluminum, an aluminum alloy, copper, and a copper alloy and a magnetic metal layer selected from nickel, nickel alloy, iron, and an iron alloy are metallurgically joined by explosive pressure bonding. An electromagnetic induction heating mold for resin molding comprising a composite layer of at least two layers, wherein a cavity surface is formed on the surface of the magnetic metal layer. Regarding type.
[0011]
In high frequency electromagnetic induction heating type injection molding, this is a molding method in which only the surface of the mold cavity is rapidly heated and heated, the resin is injected into a high-temperature cavity, and the resin is cooled using a medium such as water. In this case, an induction heating method is used for heating in order to raise the mold surface temperature in a short time of about several seconds.
[0012]
Induction heating is a method in which a metal piece to be heated is placed in a periodically changing magnetic field, and the metal piece itself is heated by eddy currents generated in the metal. It is characteristic that it is obtained.
[0013]
There are two types of injection molding methods that employ this induction heating method: a method in which an inductor is sandwiched between molds and induction heating is performed with a high-frequency transmitter, and a method in which the inductor is built in the back of the cavity. Depending on the shape, structure, material, etc.
[0014]
However, regardless of which method is used, the metal layer to be heated adjacent to the inductor is preferably a magnetic metal layer, particularly a ferromagnetic metal layer, and heat generation efficiency is good, so that rapid temperature rise can be obtained.
[0015]
Next, after filling the resin, the cavity surface metal layer heated at a high temperature and the entire mold must be cooled rapidly. For this purpose, the mold has excellent heat conductivity of cooling water and refrigerant. That is, it is preferable that heat is exchanged efficiently and that the structure has a sufficiently high rigidity.
[0016]
Further, according to the mold for resin molding of the present invention, it is formed of a composite metal layer having high thermal conductivity, preferably and having a low volume specific heat metal layer, or alternatively, the mold is heated by an inductor or a refrigerant, The metal layer to be cooled has a high thermal conductivity and is preferably formed of a low volume specific heat metal layer, so that the thermal inertia of the mold is small, and the mold when induction heating is used together is efficiently heated within one cycle. Can be cooled.
[0017]
That is, the present invention increases the heat exchange efficiency in a resin mold that performs forced heating such as electromagnetic induction heating and forced cooling with a refrigerant, thereby shortening the molding cycle time of the product, improving the molding efficiency, It is a long-life mold that suppresses the development of cracks, and is a mold that has improved molding quality, particularly surface gloss, finish accuracy, and faithful transfer accuracy on the mold surface.
[0018]
The resin molding die according to the present invention is composed of a composite layer having a high thermal conductivity, preferably at least a composite layer formed by metallurgical joining of a low volume specific heat metal layer and a magnetic metal layer. The mold of the present invention is preferably metallurgically joined to a mold base (strength member) layer in order to impart sufficient rigidity and strength to the mold or mold part. You can also. Further, the mold base layer can also be used as a magnetic metal layer.
[0019]
The high-rigidity metal used as the mold base in this invention is general structural rolled steel, carbon steel for mechanical structure, structural alloy steel, carbon tool steel, steel such as bearing steel, stainless steel and other high strength metals. High thermal conductivity and preferably low volume specific heat metal materials are aluminum, aluminum alloy, copper, copper alloy and the like.
[0020]
Here, the volume specific heat (Cal · deg ~ 1 · Cm ~ 3 ) is
It is specific heat (Cal · deg ~ 1 · g ~ 1 ) x density (g · Cm ~ 3 ), and the heat transfer from the mold and the like is all considered in terms of specific heat per volume.
[0021]
The magnetic metal material is nickel, nickel alloy, iron, iron alloy or the like.
[0022]
In addition, the mold of the present invention is configured such that the mold base is made of a low thermal conductivity material or the mold base and the high thermal conductivity in order to reduce the thermal inertia of the entire mold and improve the molding cycle. It is possible to provide metallurgical bonding by providing a bonding metal material layer having a low thermal conductivity between the low-volume specific heat metal layer. This low thermal conductivity metal material is a low thermal conductivity material such as stainless steel, titanium, titanium alloy, zirconium, zirconium alloy or the like.
[0023]
Furthermore, it is highly heat conductive for forming a cooling medium flow path for improving the molding cycle of the mold, and preferably a hole is provided inside the low volume specific heat metal layer, or the high heat conductive metal layer and A groove can be provided on the joint surface with the metal material constituting the base material layer or the cavity surface layer in contact therewith.
[0024]
High thermal conductivity, preferably a low volume specific thermal metal layer, improves thermal conductivity when thickened. Further, when the thickness is reduced, the thermal inertia can be reduced. For this reason, the optimum value of the thickness of this layer varies depending on the mold structure. For a system capable of sufficient heat exchange, a large molded article, or a mold having a complicated shape and easily varying the temperature of the mold surface, the thickness may be increased to 20 mm or more. When it is desired to provide a temperature difference between the small size and raw material charging and cooling, the thickness is set to about 5 mm to 20 mm.
[0025]
Holes or grooves provided for heat exchange are equipped with a heat medium such as water or oil, or a heat pipe or an electric heater. This hole or groove also has an effect of reducing the heat conduction area of the high heat conductivity and low volume specific heat metal layer, and reduces the heat transfer to the low heat conduction metal layer or the mold base material.
[0026]
The metallurgical bonding referred to in the present invention is a method in which two metals are bonded close to the region where the atomic attractive force acts, and is usually bonded by means such as friction pressure bonding, explosion pressure bonding, roll pressure bonding, diffusion bonding, and electroplating. To do. When it is difficult to metallurgically bond two different metals, as an intermediate material, for example, pure aluminum, titanium, nickel, pure iron, copper, silver, or a brazing material containing these as a main component Can be used together. In the present invention, by combining by metallurgical joining in this way, the thermal conductivity can be further improved as compared with that by normal fitting.
[0027]
【Example】
Example 1
Referring to the drawings, FIG. 1 is a side sectional view showing a layer structure of a resin mold (lower mold) of the present invention for injection molding (however, an upper mold having the same layer structure is not shown). .
[0028]
The mold material is composed of a mold
[0029]
The inductor 6 is disposed between the nickel alloy surface side cavity surface of the resin molding die so as to be sandwiched between upper molds (not shown), the cavity surface is heated by high frequency electromagnetic induction heating, and then the inductor 6 is removed and the glass fiber is filled. When injection molding was performed using a resin, a molded product having a beautiful surface skin was obtained because the temperature rise and cooling rate were faster than those of conventional molds and heating unevenness was small.
[0030]
Comparative Example 1
Referring to the drawings, FIG. 2 is a side sectional view showing a layer structure of a resin molding mold (lower mold) for injection molding manufactured for comparison with the mold of the present invention (however, the layer structure) The same upper mold is not shown).
[0031]
The material of this mold is a single metal of the
[0032]
The inductor 6 is arranged on the surface side of this resin molding die in the same manner as in Example 1 and the cavity surface is heated by high-frequency electromagnetic induction heating, and then glass fiber is filled with the same material and under the same conditions as in Example 1. The resin was injection molded using the resin.
[0033]
In comparison of the formation results of Example 1 and Comparative Example 1, as compared with Comparative Example 1, Example 1 is a temperature increase and cooling of a volume specific heat difference corresponding to a total of 20 mm in aluminum alloy thickness and 1 mm in nickel alloy thickness. It was found that the speed was high and heating unevenness was small.
[0040]
【The invention's effect】
The molding die of the present invention has high strength as a structural material, has high thermal conductivity and heat inertia, can greatly shorten the molding cycle, improve molding efficiency, improve thermal efficiency, and improve the mold surface. It is possible to provide a resin molding die for faithfully shaping gloss and patterns to obtain a high-quality molded product having a good appearance.
[0041]
In addition, when thermoplastic resin molding with various fillers using glass fiber, inorganic substance, metal powder, etc. is performed, the filler is not exposed on the surface of the molded product, in other words, a thin film skin of the thermoplastic resin A layer can be formed, and even a resin reinforced with a filler can obtain a surface state equivalent to that of a non-reinforced resin, and the transferability of a difficult-to-mold (high viscosity, high melting point) resin is improved. In addition, surface defects such as jetting, flow marks and weld lines can be prevented.
[0042]
Furthermore, the moldability of the high-viscosity and high-melting-point resin is improved by improving the fluidity. In addition, the internal stress and post-shrinkage of the molded product can be reduced.
[0043]
As a result, for example, the PMMA resin car stereo full panel improves quality by eliminating the weld line, and the HIPS resin small TV full panel eliminates the weld line, saves the paint, and the ABS resin hand shower hole plate. Now, it is possible to omit the drilling process by eliminating the weld line, and for ABSGF resin cosmetic containers, it is possible to reduce the thickness and paint by making use of the rigidity of the resin.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing a layer structure of a resin molding die (lower die) of the present invention.
FIG. 2 is a side sectional view showing a layer structure of a resin molding die (lower die) for injection molding for comparison with the inventive mold shown in Example 1. FIG. This mold is a single metal mold having only a base metal layer made of mold steel.
[Explanation of sign]
1: Base metal layer 2: High heat conductivity and low volume specific heat metal layer 3: Magnetic metal layer 4: Low heat conductivity metal layer 5: Cooling hole 6: Inductor
Claims (6)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18222694A JP4014232B2 (en) | 1994-08-03 | 1994-08-03 | Electromagnetic induction heating mold for resin molding |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18222694A JP4014232B2 (en) | 1994-08-03 | 1994-08-03 | Electromagnetic induction heating mold for resin molding |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0839571A JPH0839571A (en) | 1996-02-13 |
| JP4014232B2 true JP4014232B2 (en) | 2007-11-28 |
Family
ID=16114554
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18222694A Expired - Lifetime JP4014232B2 (en) | 1994-08-03 | 1994-08-03 | Electromagnetic induction heating mold for resin molding |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4014232B2 (en) |
Families Citing this family (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20010087814A (en) * | 2001-06-15 | 2001-09-26 | 장우환 | High-frequency induction heating welder for synthetic resin sheet |
| JP2004536724A (en) * | 2001-07-31 | 2004-12-09 | エスケイ ケミカルズ カンパニー リミテッド | Method for casting a product and a mold used therefor |
| JP2003089136A (en) * | 2001-09-18 | 2003-03-25 | Ricoh Co Ltd | Molding method and mold for plastic molded product |
| JP4266328B2 (en) * | 2002-06-17 | 2009-05-20 | 株式会社ナガセインテグレックス | Transfer device |
| WO2006077722A1 (en) * | 2005-01-20 | 2006-07-27 | Koyo Thermo Systems Co., Ltd. | Die heating apparatus |
| JP4152397B2 (en) * | 2005-05-10 | 2008-09-17 | 昭和電線デバイステクノロジー株式会社 | Method and apparatus for heating cylindrical mold |
| JP2008110583A (en) * | 2006-10-31 | 2008-05-15 | Alps Electric Co Ltd | Injection molding machine and injection molding method |
| JP5412386B2 (en) * | 2009-08-17 | 2014-02-12 | 株式会社スグロ鉄工 | Thin-walled bottomed cylindrical metal member and manufacturing method thereof |
| JP6040546B2 (en) * | 2011-03-29 | 2016-12-07 | 三菱化学株式会社 | Electromagnetic induction heating mold equipment for resin molding |
| JP2012214041A (en) * | 2011-03-29 | 2012-11-08 | Mitsubishi Chemicals Corp | Method for manufacturing resin molding using electromagnetic induction heating type mold apparatus for resin molding |
| JP5967834B2 (en) * | 2011-03-31 | 2016-08-10 | 広島県 | Resin molding die, method for manufacturing the resin molding die, and method for manufacturing a resin molded product |
| JP5860294B2 (en) * | 2012-01-31 | 2016-02-16 | 東洋紡株式会社 | Mold and method for producing thermoplastic resin fiber reinforced composite material molded article |
| JP5833460B2 (en) * | 2012-01-31 | 2015-12-16 | 東洋紡株式会社 | Mold and method for producing thermoplastic resin fiber reinforced composite material molded article |
| FR3015918A1 (en) * | 2013-12-31 | 2015-07-03 | Roctool | DEVICE FOR HEATING A MOLD |
| CN106346659B (en) * | 2016-11-30 | 2018-08-14 | 深圳塑能节能装备有限公司 | A kind of vulcanizing press electromagnetic induction heater |
| JP2018089823A (en) * | 2016-12-01 | 2018-06-14 | 東レ株式会社 | Fine pattern transfer apparatus and fine pattern transfer method |
| JP7801338B2 (en) * | 2020-11-28 | 2026-01-16 | ブロックワイズ エンジニアリング エルエルシー | Induction heating mold system |
| CN113213735B (en) * | 2021-05-17 | 2022-11-29 | Oppo广东移动通信有限公司 | Glass processing device and mold thereof |
-
1994
- 1994-08-03 JP JP18222694A patent/JP4014232B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0839571A (en) | 1996-02-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4014232B2 (en) | Electromagnetic induction heating mold for resin molding | |
| JP4975021B2 (en) | Thermoplastic resin mold, cavity mold, and method of manufacturing the cavity mold | |
| CN209849853U (en) | Sheet metal part die-casting forming die | |
| TW201311419A (en) | Device and method for heating a mould or tool | |
| CN111716084B (en) | A method for manufacturing a copper/steel composite injection mold with a honeycomb-implanted nail interface structure | |
| JP3366739B2 (en) | Mold for injection molding of thermoplastic resin | |
| WO2000050209A1 (en) | Moulds and method of making the same | |
| WO2018023168A1 (en) | A multi material laminated tool having improved thermal coupling | |
| JP2001259821A (en) | Amorphous alloy molded product manufacturing equipment, manufacturing mold and manufacturing method | |
| JP3414473B2 (en) | Mold for resin molding | |
| JPH0358809A (en) | Die | |
| JP3400344B2 (en) | Injection molding of plastic products | |
| JPH0124588B2 (en) | ||
| JP5234640B2 (en) | Ultra-thin light guide plate molding die and molding method | |
| JP2000000865A (en) | Plastic injection molding method | |
| CN213134987U (en) | Preparation device for composite billet | |
| JP7350255B2 (en) | Manufacturing method for foamed resin molded products | |
| US20150075701A1 (en) | Mold for thermoplastic resin molding, cavity mold, and process for producing the cavity mold | |
| JPH04173313A (en) | Mold for injection molding and injection molding method using said mold | |
| JPH1067032A (en) | Manufacturing method of hollow injection molded products | |
| JPH11188734A (en) | Mold for plastic molding and method of manufacturing this mold | |
| JP2002210781A (en) | Mold for molding synthetic resin | |
| CN112355271B (en) | Heating device for be arranged in corrugated steel plate mould die-casting process to preheat | |
| JPH051367Y2 (en) | ||
| JPH066294B2 (en) | Mold manufacturing method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20040810 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20040915 |
|
| A911 | Transfer of reconsideration by examiner before appeal (zenchi) |
Free format text: JAPANESE INTERMEDIATE CODE: A911 Effective date: 20041022 |
|
| A912 | Removal of reconsideration by examiner before appeal (zenchi) |
Free format text: JAPANESE INTERMEDIATE CODE: A912 Effective date: 20041126 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20070806 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20070911 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100921 Year of fee payment: 3 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20031125 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100921 Year of fee payment: 3 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100921 Year of fee payment: 3 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110921 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110921 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120921 Year of fee payment: 5 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130921 Year of fee payment: 6 |
|
| EXPY | Cancellation because of completion of term |