JP2004066472A - Method and device for different-typed/different-colored materials-integrated injection molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To newly provide a method and a device for accurately and efficiently manufacturing a different-typed/different-colored materials-integrated injection-molded product. <P>SOLUTION: The method and the device for accurately and efficiently manufacturing the different-typed/different-colored materials-integrated injection-molded product are characterized as follows: at least two molds for molding different parts and a shared insert, which is formed so as to be commonly attachable to each of the molds, are provided; injection molding is applied into a cavity which is formed by attaching the shared insert to one mold and performing mold clamping, so that a product component can be molded; before being cooled, the product component is taken out with the shared insert and attached to the next mold, so that the mold clamping can be performed; and product parts of the different-typed/different-colored materials are injected and sequentially molded, so as to be brought into integrally close contact with the product component. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明が属する技術分野】
本発明は異種材や異色材からなる一体形の製品を安価に且つ能率的に製造する射出成形方法およびその装置に関するものである。
【０００２】
【従来の技術】
従来、異種材や異色材からなる成形品を射出成形するには、予め１材料からなる部分品を射出成形により成形しておいて、この部分品を他の成形金型内にセットしてその他の部分を射出成形する所謂インサート成形により製造するようにしている。
【０００３】
【発明が解決しようとする課題】
しかしながら、上記のインサート成形の方法によると予め成形した部分品は自然冷却しており、その過程において補強リブ等が交差する肉厚部分などではヒケやヘコミ等の変形が発生し、インサート成形の際にはこの部分にバリ等が生じてしまうという課題がある。また部分品が自然冷却してしまっているため次の射出成形による製品部分との密着性が悪く、特に異種材、例えば融点２３０°のナイロン製の製品部品と融点１４０°〜１５０°のポリエチレン製の製品部分とをインサート成形により成形しようとしても融点が大きく異なるために殆ど密着しないという課題がある。そこで密着性をよくするためにインサートする部品を再加熱してからインサートすることも試みられているが多くの時間と手間を要するほか部分品に再加熱による反りや歪みが発生してしまうという課題がある。
【０００４】
近年では図９に示すように、２組の成形金型の各一方の割型（コア型）を１つの回転軸に取付けるとともに横移動自在とし、移動方向の離れた位置に各他方の割型（キャビ型）をそれぞれ固定取付けしておいて、１のコア型の前進により１のキャビ型と突合わせ閉じして射出により一次側製品を成形し、該一次側製品をコア型内に残したまま型別れさせ、さらに１８０度回転移動して他側２のキャビ型と突合わせ閉じして二次側製品の射出成形をするという２色成型装置の提案（同様にして垂直方向に回転・縦移動するもの）がある。この手段によると成形された一次側製品が冷却しない間に二次側製品を成形するために密着性は良好なものとはなるが、一つのコア型で２種類の製品形状を成形する必要があるために製造する製品の形状が比較的簡易なものに限定されてしまうほか、２組の成型装置を１組の成型装置の如く連動させたり、一次側製品成形後に二次側製品を成形するために両製品形状に変化できる複雑で大掛かりな機能・構造を有すコア型を製造する必要があるので金型代が非常に高価となり、また注文から納期までに長時間を要すものになってしまうという課題がある。
【課題を解決するための手段】
本発明は異なる部分を成形するための２乃至複数の成形金型と該各成形金型に共通して装着可能に形成する共用入子を用意し、１の成形金型に前記共用入子を装着してできるキャビティ内に射出成形して製品部品を成形し、該製品部品が冷却しないうちに共用入子ごと取出して次の成形金型に装着し、該製品部品と一体に密着するようにして異種／異色材の製品部分を射出成形するようにして、かかる課題を解決するようにしたのである。
【０００５】
【発明の実施の形態】
図１は本発明により成形することのできる異種材一体成形製品の一例を示すもので、ナイロン材よりなる一側に段拡部１ａを持ったパイプ状の本体１と、該本体１の中間周囲にポリエチレン材による鍔状の環体１ｂを一体に密着成形したものである。なお１ｃは密着性を補強するための突環条である。
【０００６】
このような製品を成形するには先づ図２に示すように第１のコア金型２ａ内に共用入子３を装着してから図３に示すようにキャビ金型２ｂを突き合わせ閉じして各金型２ａ，２ｂおよび共用入子３とにより形成される成形用のキャビティ４ａ内に射出ノズル５ａから溶融したポリエチレン材Ｐを射出して環体１ｂを成形するのである。次いで図４に示すようにキャビ金型２ｂを開き離し、成形した環体１ｂを共用入子３ごと取出すのである。図５（ａ）はその共用入子３の平断面図、（ｂ）は同、正面図であり、図中３ａは挿脱取扱用の突出ピンである。図６に示すように共用入子３を環体１ｂが冷却しないうちに連続して第２のコア金型２ｃ内に装着し、図７乃至図８に示すようにキャビ金型２ｄ，２ｅおよび２ｆを突き合わせ閉じして形成される成型用のキャビティ４ｂ内に射出ノズル５ｂから溶融したナイロン材Ｎを射出して本体１の部分を環体１ｂと密着一体に成形するのである。
【０００７】
先に成形した環体１ｂの温度が高い（半溶融状態）うちに本体１を射出成形するので、融点の異なる異種材料であっても高い密着性をもって一体の製品を製造することができることとなる。また環体１ｂは共用入子３ごと移動するので変形等の生ずるおそれはないものである。
【０００８】
なお共用入子３は複数個を用意しておいて、成形，移動，冷却，脱型，再装着を繰返し行うことにより各金型の空き時間をなくして連続成形を行うことができる。共用入子３の装着，取出し，並列する次の金型への移動・装着等の作業はロボット様の自動機械（図示してない）にて突出しピン３ａを把持して行うものであるが、作業者がすることもできる。
【０００９】
以上は異種２材による一体成形の例について説明したが、同種異色材・異種異色材による一体成形も同様にして行うことができる。また２種／２色材による３射出工程以上の複雑な形状の成形や、３種，３色材以上の材料を用いた一体成形も対応する第３以降の金型を準備することによって容易に実現することができる。
【００１０】
【発明の効果】
本発明は以上のようにして、異なる部分を成形するための２乃至複数の成形金型と該各成形金型に共通して装着可能に形成する共用入子を用意し、１の成形金型に前記共用入子を装着してできる成形用のキャビティ内に射出成形して製品部品を成形し、該製品部品が冷却しないうちに共用入子ごと取出して次の成形金型に装着し、型閉じにより形成されるキャビティ内に前記製品部品と一体に密着する異種／異色材の製品部分を射出成形して順次連続して密着一体成形するようにしたので、異種／異色材間の密着性を著しく向上するとともに従来のインサート成形のようなインサート製品の変形やバリの発生等を防止して後加工を要しない良質の製品を効率的に製造することができるという効果を生ずる。
【００１１】
従来と同様の単純な構造の金型にて成形作業をすることができるので、金型代の高騰を招くことなく、また金型製造期間も長時間とならないため、異種・異色材一体の成形製品を設計から短期間且つ低コストにて製造することができるという効果を生ずる。
【図面の簡単な説明】
【図１】本発明による成形する製品の１例を示すもので、（ａ）は斜視図、（ｂ）断面図
【図２】第１のコア金型内に共用入子を装着した状態を示す平断面図
【図３】同、キャビ金型を突合わせ閉じしてできるキャビティ内に射出ノズルから溶融材料を射出して製品部品を成形した状態を示す平断面図
【図４】キャビ金型を開き離し、製品部品を共用入子ごと取出しつつある状態を示す平断面図
【図５】（ａ）は取出した製品部品および共用入子の平断面図、（ｂ）は同、正面図
【図６】製品部品を共用入子ごと第２のコア金型内に装着した状態を示す平断面図
【図７】キャビ金型の一部を合わせ閉じした状態を示す平断面図
【図８】すべてのキャビ金型を装着してできたキャビティ内に射出成形して製品部分を密着一体に成形した状態を示す平断面図
【図９】従来の２色成型機の例を示す正面図
【符号の説明】
１は本体
１ｂは鍔体
１ｃは突環条
２ａは第１のコア金型
２ｂは第１のキャビ金型
２ｃは第２のコア金型
２ｄ，２ｅ，２ｆは第２のキャビ金型
３は共用入子
３ａは突出しピン
４ａ，４ｂは第２のキャビティ
５ａ，５ｂは射出ノズル[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding method and an apparatus for inexpensively and efficiently producing an integrated product made of different materials and different color materials.
[0002]
[Prior art]
Conventionally, in order to injection-mold a molded product made of a different material or a different color material, a part made of one material is molded in advance by injection molding, and this part is set in another molding die. Is manufactured by the so-called insert molding of injection molding.
[0003]
[Problems to be solved by the invention]
However, according to the insert molding method described above, the preformed part is naturally cooled, and in the process, in the thick part where the reinforcing ribs and the like intersect, deformation such as sink marks and dents occurs, and during the insert molding, Has a problem that burrs and the like are generated in this portion. In addition, because the parts are naturally cooled, the adhesion to the product part by the next injection molding is poor, and in particular, dissimilar materials, for example, a nylon product part having a melting point of 230 ° and a polyethylene part having a melting point of 140 ° to 150 ° are formed. However, there is a problem that almost no close contact occurs because the melting point is greatly different even if the product portion is molded by insert molding. In order to improve the adhesion, it has been attempted to re-heat the parts to be inserted before inserting them. However, this method requires a lot of time and effort, and also causes the parts to be warped or distorted due to re-heating. There is.
[0004]
In recent years, as shown in FIG. 9, each of the split molds (core molds) of the two sets of molding dies is attached to one rotating shaft and can be moved laterally. The (mold type) is fixedly mounted, and the primary mold is formed by injection molding to form a primary product by advancing one core mold and abutting against the one mold mold, and leaving the primary product in the core mold. Proposal of a two-color molding machine that separates the mold as it is, further rotates it by 180 degrees, butts and closes it with the mold of the other side 2 and performs injection molding of the secondary side product (similarly, rotating and vertical in the vertical direction) Moving things). According to this means, the secondary product is molded while the molded primary product is not cooled, so that the adhesiveness is good, but it is necessary to mold two types of product shapes with one core mold. Because of this, the shape of the product to be manufactured is limited to a relatively simple one. In addition, two sets of molding devices are linked together as one set of molding devices, or a secondary product is formed after forming a primary product. Therefore, it is necessary to manufacture a core mold having a complicated and large-scale function and structure that can be changed to both product shapes, so the mold cost becomes extremely expensive, and it takes a long time from order to delivery. Problem.
[Means for Solving the Problems]
The present invention provides two or a plurality of molding dies for molding different parts and a common nest formed so as to be commonly mountable to each of the molding dies, and the common nest is formed in one molding die. The product parts are molded by injection molding in the cavity that can be mounted and taken out together with the shared nest before the product parts are cooled and mounted in the next molding die, so that they come into close contact with the product parts. Thus, the problem is solved by injection-molding the product part of the different type / different color material.
[0005]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows an example of a dissimilar material integrally molded product which can be molded according to the present invention. A pipe-shaped main body 1 having a stepped portion 1a on one side made of a nylon material, and an intermediate periphery of the main body 1 are shown. And a flange-shaped ring 1b made of polyethylene material is integrally formed in close contact. Reference numeral 1c denotes a protruding ring for reinforcing adhesion.
[0006]
In order to mold such a product, first, as shown in FIG. 2, the common insert 3 is mounted in the first core mold 2a, and then the mold cavity 2b is abutted and closed as shown in FIG. The molten polyethylene material P is injected from the injection nozzle 5a into the molding cavity 4a formed by the respective molds 2a and 2b and the common insert 3, thereby forming the ring 1b. Next, as shown in FIG. 4, the mold 2b is opened and separated, and the molded ring 1b is taken out together with the common insert 3. FIG. 5 (a) is a plan sectional view of the common nest 3, and FIG. 5 (b) is a front view of the same, and 3a denotes a protruding pin for insertion / removal handling. As shown in FIG. 6, the common insert 3 is continuously mounted in the second core mold 2c before the annular body 1b is cooled, and the molds 2d, 2e and 2e are formed as shown in FIGS. The molten nylon material N is injected from an injection nozzle 5b into a molding cavity 4b formed by abutting and closing the 2f, and the body 1 is molded integrally with the ring 1b.
[0007]
Since the main body 1 is injection-molded while the temperature of the previously formed annular body 1b is high (semi-molten state), an integrated product can be manufactured with high adhesion even with different materials having different melting points. . Further, since the ring 1b moves together with the common insert 3, there is no danger of deformation or the like.
[0008]
A plurality of common inserts 3 are prepared, and the molding, moving, cooling, demolding, and remounting are repeated to eliminate the idle time of each mold, thereby enabling continuous molding. The work of mounting and removing the common nest 3, moving and mounting to the next mold in parallel is performed by holding the protruding pin 3 a by an automatic machine (not shown) such as a robot. Workers can also do it.
[0009]
In the above, an example of integral molding with two different materials has been described. However, integral molding with the same type of different color material / different different color material can be performed in the same manner. In addition, molding of complicated shapes with three or more injection processes using two / two color materials, and integral molding with three or more materials using three or more color materials can be easily performed by preparing third and subsequent dies. Can be realized.
[0010]
【The invention's effect】
As described above, the present invention provides two or a plurality of molding dies for molding different parts and a common nest formed so as to be commonly mountable to each of the molding dies. Injection molding is performed into a molding cavity formed by mounting the common nest, and a product part is formed.Then, the entire common nest is taken out before the product part is cooled, and is mounted on the next molding die. The different / different color product parts, which are in close contact with the product part, are injection-molded in the cavity formed by closing and are successively and closely contacted and integrally molded, so that the adhesion between the different / different color materials is improved. As a result, it is possible to remarkably improve and prevent the deformation and burrs of the insert product as in the conventional insert molding, thereby effectively producing a high-quality product that does not require post-processing.
[0011]
Molding work can be performed using a mold with the same simple structure as before, so that the cost of the mold does not rise so much, and the mold manufacturing period does not become long, so that the molding of different and different color materials can be integrated. This produces an effect that a product can be manufactured in a short period of time and at low cost from design.
[Brief description of the drawings]
FIG. 1 shows an example of a product to be molded according to the present invention, in which (a) is a perspective view, and (b) is a cross-sectional view. FIG. 2 shows a state in which a common insert is mounted in a first core mold. FIG. 3 is a plane sectional view showing a state in which a molten material is injected from an injection nozzle into a cavity formed by butt-closing a mold and molding a product part. And FIG. 5 (a) is a cross-sectional view of the removed product part and the common nest, and FIG. 5 (b) is a front view of the same. FIG. 6 is a plan sectional view showing a state in which the product parts are mounted together with the common insert in the second core mold. FIG. 7 is a plan sectional view showing a state in which a part of the mold is fitted and closed. Shows the state in which the product part is molded in close contact with the cavity formed by mounting all the molds. Front view illustrating an example of a cross-sectional plan view and FIG. 9 conventional two-color molding machine [Description of symbols]
1 is a main body 1b, a collar body 1c, a protruding ring 2a, a first core mold 2b, a first mold 2c, a second mold 2d, 2e, 2f is a second mold 3, and The common insert 3a is projected and the pins 4a and 4b are second cavities 5a and 5b are injection nozzles.

Claims (2)

異なる部分を成形するための２乃至複数の成形金型と該各成形金型に共通して装着可能に形成する共用入子を用意し、１の成形金型に前記共用入子を装着し型閉じしてできるキャビティ内に射出成形して製品部品を成形し、該製品部品が冷却しないうちに共用入子ごと取出して次の成形金型に装着して型閉じし、該製品部品と一体に密着するように異種／異色材の製品部分を射出して順次成形するようにしたことを特徴とする異種／異色材一体形の射出成形方法。Two or a plurality of molding dies for molding different parts and a common nest formed so as to be mountable in common with each of the molding dies are prepared, and the common nest is mounted on one molding die. A product part is formed by injection molding in a cavity formed by closing, and before the product part is cooled, the common nest is taken out, attached to the next molding die, closed, and integrally formed with the product part. An injection molding method for a heterogeneous / heterochromic material integrated, wherein a product portion of a heterogeneous / heterochromic material is injected and closely molded. 異なる部分を成形するための２乃至複数の成形金型と、該各成形金型に共通して装着可能で且つ成形品ととも取出し可能とする共用入子とよりなり、１の成形金型に前記共用入子を装着して形成される成形用のキャビティ内に射出して成形する製品部品と、該製品部品を共用入子ごと取出して次の成形金型に装着し型閉じしてできる成形用のキャビティ内に異種／異色材の射出により前記製品部品と一体に密着する製品部分を射出成形して異種／異色材一体形の製品を順次成形するようにしたことを特徴とする異種／異色材一体形の射出成形装置。It consists of two or more molding dies for molding different parts, and a common nest that can be mounted in common with each of the molding dies and can be taken out together with the molded product. A product part to be molded by injection into a molding cavity formed by mounting the common nest, and a product formed by removing the product part together with the common nest, mounting the same in the next molding die, and closing the mold. A product part integrally adhered to the product part by injection of a heterogeneous / heterochromic material into a cavity for use to form a heterogeneous / heterochromic material integrated product sequentially. Injection molding machine with integrated material.

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