JPH091589A - Method for molding of bicolor resin molded product and mold structure for molding of bicolor resin - Google Patents
Method for molding of bicolor resin molded product and mold structure for molding of bicolor resinInfo
- Publication number
- JPH091589A JPH091589A JP15079095A JP15079095A JPH091589A JP H091589 A JPH091589 A JP H091589A JP 15079095 A JP15079095 A JP 15079095A JP 15079095 A JP15079095 A JP 15079095A JP H091589 A JPH091589 A JP H091589A
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- Prior art keywords
- molding
- primary
- molding part
- primary molding
- cavity
- 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.)
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- Moulds For Moulding Plastics Or The Like (AREA)
- Injection Moulding Of Plastics Or The Like (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、互いに色調が異なる一
次成形部と二次成形部とを相互に接合一体化してなる二
色樹脂成形品の成形方法および二色樹脂成形用の金型構
造に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for molding a two-color resin molded product in which a primary molding part and a secondary molding part having different color tones are joined and integrated with each other, and a die structure for two-color resin molding. Regarding
【０００２】[0002]
【従来の技術】樹脂成形品のなかには、図３に示すよう
に、アクリル樹脂からなる断面略コ字状の白色透明な一
次成形部２と、同じくアクリル樹脂からなる断面略コ字
状の赤色透明な二次成形部３とを、それぞれの一方の脚
部２ａ，３ａの外側面を接合面として相互に接合一体化
して二色樹脂成形品１としたものがある。そして、この
ような二色樹脂成形品１は例えば自動車のリヤコンビネ
ーションランプユニットのレンズとして使用される。2. Description of the Related Art Among resin molded products, as shown in FIG. 3, a white and transparent primary molding part 2 made of acrylic resin and having a substantially U-shaped cross section, and a red transparent material having a substantially U-shaped cross section and also made of an acrylic resin. There is a two-color resin molded product 1 in which the secondary molding part 3 and the other secondary molding part 3 are bonded and integrated with each other by using the outer surfaces of the respective one leg parts 2a, 3a as bonding surfaces. Then, such a two-color resin molded product 1 is used, for example, as a lens of a rear combination lamp unit of an automobile.
【０００３】上記のような二色樹脂成形品１を射出成形
法によって成形するには、例えば図４の（Ａ）に示すよ
うに、コアブロック４と第１のキャビティブロック５と
を型締めして一次成形部用のキャビティ６を形成し、こ
のキャビティ６に対してスプルー７から所定の樹脂材料
を射出・充填して一次成形部２を成形したのちに、その
一次成形部２をコアブロック４側に残したままで型開き
する。To mold the above-mentioned two-color resin molded product 1 by the injection molding method, for example, as shown in FIG. 4A, the core block 4 and the first cavity block 5 are clamped. To form a cavity 6 for the primary molding portion, and to inject and fill a predetermined resin material from the sprue 7 into the cavity 6 to mold the primary molding portion 2, and then to fix the primary molding portion 2 to the core block 4 Open the mold leaving it on the side.
【０００４】そして、同図（Ｂ）に示すように、一次成
形部２が残されているコアブロック４に対して先に使用
した第１のキャビティブロック５に代えて第２のキャビ
ティブロック８を組み合わせて型締めし、それらコアブ
ロック４と第２のキャビティブロック８および一次成形
部２の三者によって二次成形部用のキャビティ９を形成
する。Then, as shown in FIG. 1B, a second cavity block 8 is used instead of the first cavity block 5 previously used for the core block 4 in which the primary molding portion 2 is left. The molds are combined and clamped, and the core block 4, the second cavity block 8 and the primary molding part 2 form a cavity 9 for the secondary molding part.
【０００５】そののちに、キャビティ９に対してスプル
ー１０から所定の樹脂材料を射出・充填することにより
二次成形部３が成形され、同時にその二次成形部３が一
次成形部２と接合一体化されて図２に示したような二色
樹脂成形品１が得られることになる。After that, the secondary molding part 3 is molded by injecting and filling a predetermined resin material into the cavity 9 from the sprue 10, and at the same time, the secondary molding part 3 is joined and integrated with the primary molding part 2. As a result, the two-color resin molded product 1 as shown in FIG. 2 is obtained.
【０００６】このようにして成形された二色樹脂成形品
１は、同図（Ｃ）に示すように、型開き後にコアブロッ
ク４側に設けられた複数のエジェクタピン１１により突
き出されて脱型される。The two-color resin molded product 1 molded in this way is ejected by a plurality of ejector pins 11 provided on the core block 4 side after the mold is opened, as shown in FIG. To be done.
【０００７】ここで、二次成形部３を成形する際にその
二次成形圧によって一次成形部２と二次成形部３との境
界１２の位置が変動することがないように、一次成形部
２は第２のキャビティブロック８によって型締め方向に
加圧拘束されてΔｔだけ圧縮される。Here, when the secondary molding part 3 is molded, the position of the boundary 12 between the primary molding part 2 and the secondary molding part 3 does not change due to the secondary molding pressure, so that the primary molding part does not change. The second cavity block 8 is pressed and restrained in the mold clamping direction by the second cavity block 8 and compressed by Δt.
【０００８】[0008]
【発明が解決しようとする課題】上記のような従来の成
形方法においては、コアブロック４と二次成形部用の第
２のキャビティブロック８との型締め時に、そのコアブ
ロック４と第２のキャビティブロック８との間で一次成
形部２の全面を加圧拘束するようにしているために型締
め力のバランスが悪く、第２のキャビティブロック８の
全面に成形機の型締め力が均等に作用しないという問題
がある。In the conventional molding method as described above, when the core block 4 and the second cavity block 8 for the secondary molding portion are clamped, the core block 4 and the second cavity block 8 are clamped. Since the entire surface of the primary molding part 2 is pressed and restrained with the cavity block 8, the mold clamping force is unbalanced, and the mold clamping force of the molding machine is evenly distributed over the entire surface of the second cavity block 8. There is a problem that it does not work.
【０００９】より詳しくは、コアブロック４と第２のキ
ャビティブロック８のうち一次成形部２に相当する部分
では両者が一次成形部２を介して全面接触しているため
に、その一次成形部２を加圧拘束する上では型締め力が
有効に作用したとしても、型締め力の多くが上記のよう
に一次成形部２の加圧拘束のために過剰に消費されてし
まうことによって、相対的に二次成形部用のキャビティ
９を隔成形成するために型締め力が不足することにな
る。More specifically, since the core block 4 and the second cavity block 8 are in full contact with each other through the primary molding part 2 in the portion corresponding to the primary molding part 2, the primary molding part 2 is in contact with the primary molding part 2. Even if the mold clamping force is effectively applied to pressurize and constrain, the mold clamping force is excessively consumed due to the pressurizing constraint of the primary molding unit 2 as described above. Since the cavity 9 for the secondary molding portion is formed separately, the mold clamping force becomes insufficient.
【００１０】そのため、二次成形部３の成形時に、コア
ブロック４および第２のキャビティブロック８のうち二
次成形部３に相当する部分がその成形圧力（射出圧力）
によって型開き方向に一旦撓みを生じ、射出完了後の保
圧過程に移行すると内圧の低下とともに元の状態に復元
するという現象が顕著にあらわれ、それに応じて二次成
形部３となるべきキャビティ９の空間容積も一旦膨張し
た上で収縮することになる。Therefore, at the time of molding the secondary molding portion 3, the portion of the core block 4 and the second cavity block 8 corresponding to the secondary molding portion 3 has its molding pressure (injection pressure).
As a result, the phenomenon that the bending occurs once in the mold opening direction and the state returns to the original state with the decrease of the internal pressure when shifting to the pressure-holding process after the completion of injection, the cavity 9 that should become the secondary molding portion 3 accordingly appears. The space volume of will also expand and then contract.
【００１１】その結果、二次成形部３のうち特にその脚
部３ａがコアブロック４に対していわゆる食い付き現象
を生じ、図４の（Ｃ）に示すようにエジェクタピン１１
で成形完了後の二色樹脂成形品１を突き出した場合に、
その二次成形部３の内コーナー部にクラック１３が発生
することとなって好ましくない。As a result, the leg portion 3a of the secondary molding portion 3 causes a so-called biting phenomenon with respect to the core block 4, and as shown in FIG. 4C, the ejector pin 11 is formed.
When the two-color resin molded product 1 after molding is completed,
Cracks 13 are generated at the inner corners of the secondary molded portion 3, which is not preferable.
【００１２】本発明は以上のような課題に着目してなさ
れたもので、二次成形部の成形時に一次成形部を加圧拘
束すべき領域の位置および面積の最適化を図ることによ
って、成形機の型締め力を二次成形部となるべき部分に
有効に作用させてクラック等の発生を未然に防止した成
形方法および金型構造を提供することを目的としてい
る。The present invention has been made in view of the above problems. By optimizing the position and area of the region to which the primary molding part should be pressed and restrained at the time of molding the secondary molding part, the molding is performed. An object of the present invention is to provide a molding method and a mold structure in which a mold clamping force of a machine is effectively applied to a portion to be a secondary molding portion to prevent cracks and the like from occurring.
【００１３】[0013]
【課題を解決するための手段】請求項１に記載の発明
は、断面略コ字状の一次成形部と、この一次成形部とは
異色の樹脂材料で成形される同じく断面略コ字状の二次
成形部とを、各成形部の一方の脚部の外側面を接合面と
して接合一体化してなる二色樹脂成形品を成形する方法
であって、コアブロックと第１のキャビティブロックと
で形成される一次成形部用のキャビティに樹脂材料を充
填して一次成形部を成形する工程と、前記一次成形部を
コアブロック側に残したまま型開きして、前記第１のキ
ャビティブロックに代えて第２のキャビティブロックと
コアブロックとを型締めすることにより、第２のキャビ
ティブロック２で一次成形部を加圧拘束しながらこの第
２のキャビティブロックとコアブロックおよび一次成形
部とで二次成形部用のキャビティを形成する工程と、前
記二次成形部用のキャビティに樹脂材料を充填して二次
成形部を成形しながら一次成形部と接合一体化して、こ
れら一次，二次成形部よりなる二色樹脂成形品形状を得
る工程とを含んでなり、前記二次成形部の成形時に第２
のキャビティブロックにて一次成形部を加圧拘束すべき
領域を、二次成形部との境界を基準に該境界から所定の
幅Ｗ11の範囲内に限定し、この加圧拘束領域の幅寸法Ｗ
11を次式で求められる値に設定したことを特徴としてい
る。According to a first aspect of the present invention, there is provided a primary molding portion having a substantially U-shaped cross section, and the primary molding portion having a substantially U-shaped cross section formed of a resin material having a different color. A method for molding a two-color resin molded product, which comprises integrally bonding a secondary molding part with an outer surface of one leg of each molding part as a bonding surface, which comprises a core block and a first cavity block. Filling the cavity for the primary molding portion to be formed with a resin material to mold the primary molding portion, and opening the mold with the primary molding portion left on the core block side to replace the first cavity block. By clamping the second cavity block and the core block with each other by pressing, the second cavity block 2 pressurizes and restrains the primary molding portion, and the second cavity block, the core block and the primary molding portion perform the secondary molding. For forming part A step of forming a cavity, and a cavity for the secondary molding part is filled with a resin material to mold the secondary molding part while being joined and integrated with the primary molding part. And a step of obtaining the shape of the resin molded product,
In the cavity block, the region where the primary molding portion is to be pressure-restrained is limited to a predetermined width W 11 from the boundary with the secondary molding portion as a reference, and the width dimension of the pressure-restraining region is limited. W
The feature is that 11 is set to the value obtained by the following equation.
【００１４】 Ｗ11＝（Ｔ−Ｓ2б2）／｛Ｌ1Ｙ（Δｔ1／ｔ1）｝‥‥‥（１） Ｌ1：一次成形部の投影面の長さ Ｓ2：二次成形部の投影面積 Ｔ：成形機の型締め力 ｔ1：一次成形部の板厚 Δｔ1：一次成形部の圧縮量（経験値） б1＝Ｙ（Δｔ1／ｔ1）：一次成形部の圧縮応力 б2：二次成形部の成形圧力 Ｓ11＝Ｌ1・Ｗ11：一次成形部の最適加圧面積 請求項２に記載の発明は、断面略コ字状の一次成形部
と、この一次成形部とは異色の樹脂材料で成形される同
じく断面略コ字状の二次成形部とを、各成形部の一方の
脚部の外側面を接合面として接合一体化してなる二色樹
脂成形品を成形するにあたり、コアブロックと第１のキ
ャビティブロックとで形成される一次成形部用のキャビ
ティに樹脂材料を充填して一次成形部を成形したのち
に、前記一次成形部をコアブロック側に残したまま型開
きして、前記第１のキャビティブロックに代えて第２の
キャビティブロックとコアブロックとを型締めすること
により、第２のキャビティブロックで一次成形部を加圧
拘束しながらこの第２のキャビティブロックとコアブロ
ックおよび一次成形部とで二次成形部用のキャビティを
形成し、前記二次成形部用のキャビティに樹脂材料を充
填して二次成形部を成形しながら一次成形部と接合一体
化して、これら一次，二次成形部よりなる二色樹脂成形
品形状を得るようにした金型構造であって、前記第２の
キャビティブロックのうち一次成形部と二次成形部との
境界に沿う部分に、その境界から一次成形部側にかけて
所定の幅Ｗ11を有して且つ一次成形部に直接接触して該
一次成形部を加圧拘束する押圧部を形成し、この押圧部
の幅寸法Ｗ11を上記の（１）式で求められる値に設定し
たことを特徴としている。W 11 = (T−S 2 б 2 ) / {L 1 Y (Δt 1 / t 1 )} ... (1) L 1 : Length of projection surface of primary molding part S 2 : Secondary Projected area of molding part T: Mold clamping force of molding machine t 1 : Plate thickness of primary molding part Δt 1 : Compression amount of primary molding part (empirical value) б 1 = Y (Δt 1 / t 1 ): Primary molding part Compressive stress б 2 : Molding pressure of the secondary molding part S 11 = L 1 · W 11 : Optimum pressing area of the primary molding part The invention according to claim 2 is a primary molding part having a substantially U-shaped cross section, A two-color structure in which a secondary molding part having a substantially U-shaped cross section and molded from a resin material of a different color from this primary molding part is joined and integrated by using the outer surface of one leg of each molding part as a joint surface. When molding a resin molded product, a resin material is filled in the cavity for the primary molding part formed by the core block and the first cavity block to mold the primary molding part. After that, the mold is opened with the primary molding part left on the core block side, and the second cavity block and the core block are clamped in place of the first cavity block, whereby the second cavity block is closed. While pressurizing and restraining the primary molding part, a cavity for the secondary molding part is formed by the second cavity block, the core block and the primary molding part, and a resin material is filled in the cavity for the secondary molding part. A mold structure in which a secondary molding part is joined and integrated with a primary molding part while molding to obtain a shape of a two-color resin molded product composed of these primary and secondary molding parts. the portion along the boundary between the primary molding section and a secondary molding portion of the block, the primary molding section in direct contact with the and the primary molding section having a predetermined width W 11 from the boundary toward the primary molding section side Forming a pressing portion for pressing restraint, and the width W 11 of the pressing portion characterized in that set to a value obtained by equation (1) above.
【００１５】[0015]
【作用】請求項１，２に記載の発明によると、二次成形
部の成形時に一次成形部を加圧拘束すべき領域を、一次
成形部のうち二次成形部との境界に近い部分のみに限定
し、その領域の幅寸法Ｗ11ひいては面積を特定の値に設
定することにより、型締め力で一次成形部を効果的に加
圧拘束しながら、その型締め力を二次成形部を成形すべ
きキャビティの型締め力として有効に作用させることが
できるようになる。その結果、第２のキャビティブロッ
クの撓みを防止して二次成形部のクラック等の発生を未
然に防止できるようになる。According to the first and second aspects of the present invention, only the region of the primary molding portion near the boundary with the secondary molding portion is to be pressed and restrained when molding the secondary molding portion. By limiting the width dimension W 11 of the region and thus the area to a specific value, the mold clamping force is effectively restrained while the primary molding part is pressed and restrained. It becomes possible to effectively act as the mold clamping force of the cavity to be molded. As a result, it is possible to prevent the second cavity block from bending and prevent the occurrence of cracks or the like in the secondary molding portion.
【００１６】[0016]
【実施例】図１，２は本発明の一実施例を示す図であっ
て、図４と共通する部分には同一符号を付してある。す
なわち、一次成形部２を成形するための第１のキャビテ
ィブロック５の形状は従来のものと同様であるが、二次
成形部３を成形するための第２のキャビティブロック８
の形状が従来のものと異なっている。1 and 2 are views showing an embodiment of the present invention, in which the same parts as those in FIG. 4 are designated by the same reference numerals. That is, the shape of the first cavity block 5 for molding the primary molding portion 2 is similar to that of the conventional one, but the second cavity block 8 for molding the secondary molding portion 3 is formed.
The shape is different from the conventional one.
【００１７】より詳しくは、図１および図２の（Ｂ）に
示すように、一次成形部２の成形後に、その一次成形部
用の第１のキャビティブロック５に代えて二次成形部用
の第２のキャビティブロック８とコアブロック４とを型
締めして、その第２のキャビティブロック８で一次成形
部２を加圧拘束しながら二次成形部３を成形することに
なるのであるが、その第２のキャビティブロック８のう
ち一次成形部２と二次成形部との境界１２に相当する部
分には一次成形部２を加圧拘束するための押圧部１４を
一次成形部２の全長にわたって有段成形してある。More specifically, as shown in FIG. 1 and FIG. 2B, after the primary molding part 2 is molded, it is used for the secondary molding part instead of the first cavity block 5 for the primary molding part. The second cavity block 8 and the core block 4 are clamped together, and the secondary molding portion 3 is molded while the primary molding portion 2 is pressed and restrained by the second cavity block 8. In the portion of the second cavity block 8 corresponding to the boundary 12 between the primary molding portion 2 and the secondary molding portion, a pressing portion 14 for pressurizing and restraining the primary molding portion 2 is provided over the entire length of the primary molding portion 2. It is stepped.
【００１８】この押圧部１４は、図１，２のほか図３に
示すように、第２のキャビティブロック８のうち二次成
形部用のキャビティ９を形成する成形面９ａに連続する
ように一次，二次成形部２，３同士の境界１２から一次
成形部２側にかけて所定の幅Ｗ11にわたって形成され、
かつその押圧部１４の長さは一次成形部２の長さＬ1と
等しいものとなっている。As shown in FIG. 3 in addition to FIGS. 1 and 2, the pressing portion 14 is primary so as to be continuous with the molding surface 9a forming the cavity 9 for the secondary molding portion of the second cavity block 8. , Formed over a predetermined width W 11 from the boundary 12 between the secondary molding portions 2 and 3 to the primary molding portion 2 side,
The length of the pressing portion 14 is equal to the length L 1 of the primary molding portion 2.
【００１９】そして、前記押圧部１４による一次成形部
２の加圧面積が最適加圧面積となるように前記押圧部１
４の幅寸法Ｗ11が次式により導かれて設定されている。Then, the pressing portion 1 is adjusted so that the pressing area of the primary molding portion 2 by the pressing portion 14 becomes an optimum pressing area.
The width W 11 of 4 is set by being guided by the following equation.
【００２０】すなわち、 Ｓ1＝Ｌ1×Ｗ1：一次成形部の投影面積 Ｌ1：一次成形部の投影面の長さ Ｗ1：一次成形部の投影面の幅 Ｓ2：二次成形部の投影面積 Ｔ：成形機の型締め力 ｔ1：一次成形部の板厚 Δｔ1：一次成形部の圧縮量（経験値） ε1＝Δｔ1／ｔ1：一次成形部の圧縮率 б1＝Ｙ（ε1）：一次成形部の圧縮応力（圧縮歪み試験
で求まる） б2：二次成形部の成形圧力 Ｓ11＝Ｌ1×Ｗ11：一次成形部の最適加圧面積 として Ｔ＝Ｓ2б2＋Ｓ11б1より Ｓ11＝（Ｔ−Ｓ2б2）／б1 б1＝Ｙ（ε1）＝Ｙ（Δｔ1／ｔ1）より Ｓ11＝（Ｔ−Ｓ2б2）／Ｙ（Δｔ1／ｔ1） Ｓ11＝ｌ1×Ｗ11より Ｗ11＝（Ｔ−Ｓ2б2）／｛Ｌ1Ｙ（Δｔ1／ｔ1）｝ したがって、本実施例によれば、図１および図２の
（Ｂ）に示すように、一次成形部２の成形後であって二
次成形部３の成形に先立ち、第２のキャビティブロック
８とコアブロック４とを型締めした場合に、一次成形部
２は押圧部１４の幅Ｗ11のみで第２のキャビティブロッ
ク８により加圧拘束される。That is, S 1 = L 1 × W 1 : projected area of the primary molding portion L 1 : length of projection surface of the primary molding portion W 1 : width of projection surface of the primary molding portion S 2 : secondary molding portion Projected area T: Clamping force of molding machine t 1 : Plate thickness of primary molding part Δt 1 : Compression amount of primary molding part (empirical value) ε 1 = Δt 1 / t 1 : Compressibility of primary molding part б 1 = Y (ε 1 ): Compressive stress of the primary molding part (obtained by compressive strain test) б 2 : Molding pressure of the secondary molding part S 11 = L 1 × W 11 : As the optimum pressing area of the primary molding part T = From S 2 б 2 + S 11 б 1 From S 11 = (T-S 2 б 2 ) / б 1 б 1 = Y (ε 1 ) = Y (Δt 1 / t 1 ) S 11 = (T-S 2 б 2 ) / Y (Δt 1 / t 1 ) S 11 = l 1 × W 11 From W 11 = (T−S 2 б 2 ) / {L 1 Y (Δt 1 / t 1 )} Therefore, in the present embodiment, Therefore, as shown in FIG. 1 and FIG. When the second cavity block 8 and the core block 4 are clamped after the molding of the primary molding part 2 and prior to the molding of the secondary molding part 3, the primary molding part 2 has the width of the pressing part 14. The pressure is restrained by the second cavity block 8 only by W 11 .
【００２１】そして、前記第２のキャビティブロック８
とコアブロック４および一次成形部２とで画成されるキ
ャビティ９に二次成形部用の樹脂材料を射出することに
より二次成形部３が成形され、同時にその二次成形部３
は境界１２において一次成形部２と接合して一体化され
て最終的には二色樹脂成形品１が成形されることにな
る。Then, the second cavity block 8
The secondary molding part 3 is molded by injecting the resin material for the secondary molding part into the cavity 9 defined by the core block 4 and the primary molding part 2, and at the same time the secondary molding part 3 is molded.
Is joined and integrated with the primary molding part 2 at the boundary 12, and finally the two-color resin molded product 1 is molded.
【００２２】その際、成形機の型締め力は従来のものと
同一であっても、第２のキャビティブロック８で一次成
形部２の全体を加圧拘束するのではなく一次成形部２の
うち二次成形部３に最も近い幅Ｗ11の範囲のみを局部的
に第２のキャビティブロック８で加圧拘束していること
から、二次成形部３を成形するための型締め力のバラン
スがよくなり、型締め力が二次成形部用のキャビティ９
側に効果的に作用するようになる。At this time, even if the mold clamping force of the molding machine is the same as the conventional one, the second cavity block 8 does not press and constrain the entire primary molding part 2 but the primary molding part 2 Since the second cavity block 8 locally pressurizes and constrains only the range of the width W 11 that is closest to the secondary molding portion 3, the balance of the mold clamping force for molding the secondary molding portion 3 is balanced. Improves the mold clamping force and the cavity 9 for the secondary molding part.
To work effectively on the side.
【００２３】そのため、二次成形部３の成形圧力によっ
て第２のキャビティブロック８に撓みを生じることがな
くなることから、保圧行程の末期に至っても二次成形部
３の脚部３ａがコアブロック４に対していわゆる食い付
き現象を生じることがない。その結果、図２の（Ｃ）に
示すように型開き後に二色樹脂成形品１を複数のエジェ
クタピン１１で突き出しても、成形品１はコアブロック
４から無理なく脱型されて、従来のようにクラック１３
（図４の（Ｃ）参照）が発生することがない。ここで、
前記実施例では、図３に示すように上面がフラットな二
色樹脂成形品１を成形する場合の例を示したが、成形品
が受けるべき型締め力はその成形品の投影面積で決まる
ために、上面が湾曲しているような成形品を成形する場
合にも本発明を同様に適用することができる。Therefore, since the second cavity block 8 is not bent due to the molding pressure of the secondary molding portion 3, the leg portion 3a of the secondary molding portion 3 is made the core block even at the end of the pressure-holding process. No so-called biting phenomenon occurs with respect to No. 4. As a result, as shown in FIG. 2C, even if the two-color resin molded product 1 is ejected by the plurality of ejector pins 11 after the mold is opened, the molded product 1 is easily released from the core block 4 and the conventional mold 1 is removed. So crack 13
(See FIG. 4C) does not occur. here,
In the above-mentioned embodiment, an example of molding a two-color resin molded product 1 having a flat upper surface as shown in FIG. 3 is shown, but the mold clamping force to be received by the molded product is determined by the projected area of the molded product. In addition, the present invention can be similarly applied to the case of molding a molded product having a curved upper surface.
【００２４】[0024]
【発明の効果】請求項１，２に記載の発明によれば、二
次成形部の成形の際に第２のキャビティブロックの押圧
部にて一次成形部を加圧拘束すべき領域を、その一次成
形部のうち二次成形部との境界に近い一部分に限定し、
その領域の幅寸法を、一次成形部の最適加圧面積を充足
するような特定の値に設定したことにより、従来では一
次成形部を過剰に加圧拘束していたがために型締め力の
バランスが悪くなって二次成形部の成形時に第２のキャ
ビティブロックに撓みが生じていたのに対し、本発明で
は型締め力のバランスがよくなって型締め力が二次成形
部用のキャビティに有効に作用することからそのような
不具合が解消される。その結果、コアブロックに対する
二次成形部のいわゆる食い付き現象が防止されて、脱型
時のクラックの発生がなくなり、成形品質の向上に大き
く貢献することができる。According to the first and second aspects of the present invention, the region where the pressing portion of the second cavity block should press and restrain the primary molding portion when molding the secondary molding portion, Limited to a part of the primary molding part near the boundary with the secondary molding part,
By setting the width of the region to a specific value that satisfies the optimum pressure area of the primary molding part, the mold clamping force of While the balance is not good and the second cavity block is bent at the time of molding the secondary molding portion, the mold clamping force is well balanced and the mold clamping force is equal to the cavity for the secondary molding portion in the present invention. It effectively eliminates such a problem. As a result, the so-called biting phenomenon of the secondary molding portion with respect to the core block is prevented, the occurrence of cracks at the time of demolding is eliminated, and it is possible to greatly contribute to the improvement of molding quality.
【図１】本発明の一実施例を示す図で、図２の（Ｂ）の
拡大図。FIG. 1 is a view showing an embodiment of the present invention and is an enlarged view of FIG. 2 (B).
【図２】本発明の一実施例を示す二色樹脂成形方法の工
程説明図。FIG. 2 is a process explanatory view of a two-color resin molding method showing an embodiment of the present invention.
【図３】二色樹脂成形品の一例を示す斜視図。FIG. 3 is a perspective view showing an example of a two-color resin molded product.
【図４】従来の二色樹脂成形方法の工程説明図。FIG. 4 is a process explanatory view of a conventional two-color resin molding method.
１…二色樹脂成形品 ２…一次成形部 ３…二次成形部 ４…コアブロック ５…第１のキャビティブロック ６…一次成形部用のキャビティ ８…第２のキャビティブロック ９…二次成形部用のキャビティ １２…境界 １４…押圧部 Ｗ11…押圧部の幅DESCRIPTION OF SYMBOLS 1 ... Two-color resin molded product 2 ... Primary molding part 3 ... Secondary molding part 4 ... Core block 5 ... 1st cavity block 6 ... Cavity for primary molding part 8 ... 2nd cavity block 9 ... Secondary molding part Cavity 12 ... Boundary 14 ... Pressing part W 11 ... Width of pressing part
Claims (2)
成形部とは異色の樹脂材料で成形される同じく断面略コ
字状の二次成形部とを、各成形部の一方の脚部の外側面
を接合面として接合一体化してなる二色樹脂成形品を成
形する方法であって、 コアブロックと第１のキャビティブロックとで形成され
る一次成形部用のキャビティに樹脂材料を充填して一次
成形部を成形する工程と、 前記一次成形部をコアブロック側に残したまま型開きし
て、前記第１のキャビティブロックに代えて第２のキャ
ビティブロックとコアブロックとを型締めすることによ
り、第２のキャビティブロック２で一次成形部を加圧拘
束しながらこの第２のキャビティブロックとコアブロッ
クおよび一次成形部とで二次成形部用のキャビティを形
成する工程と、 前記二次成形部用のキャビティに樹脂材料を充填して二
次成形部を成形しながら一次成形部と接合一体化して、
これら一次，二次成形部よりなる二色樹脂成形品形状を
得る工程とを含んでなり、 前記二次成形部の成形時に第２のキャビティブロックに
て一次成形部を加圧拘束すべき領域を、二次成形部との
境界を基準に該境界から所定の幅Ｗ11の範囲内に限定
し、この加圧拘束領域の幅寸法Ｗ11を次式で求められる
値に設定したことを特徴とする二色樹脂成形品の成形方
法。 Ｗ11＝（Ｔ−Ｓ2б2）／｛Ｌ1Ｙ（Δｔ1／ｔ1）｝ Ｌ1：一次成形部の投影面の長さ Ｓ2：二次成形部の投影面積 Ｔ：成形機の型締め力 ｔ1：一次成形部の板厚 Δｔ1：一次成形部の圧縮量（経験値） б1＝Ｙ（Δｔ1／ｔ1）：一次成形部の圧縮応力 б2：二次成形部の成形圧力 Ｓ11＝Ｌ1・Ｗ11：一次成形部の最適加圧面積1. A primary molding part having a substantially U-shaped cross section, and a secondary molding part having a substantially U-shaped cross-section, which is molded from a resin material having a different color from the primary molding part, of one of the molding parts. A method for molding a two-color resin molded product by integrally bonding the outer surfaces of the legs as bonding surfaces, wherein a resin material is applied to a cavity for a primary molding part formed by a core block and a first cavity block. Filling and molding the primary molding part, and mold opening with the primary molding part left on the core block side, and clamping the second cavity block and the core block in place of the first cavity block. Thereby forming a cavity for the secondary molding portion by the second cavity block, the core block and the primary molding portion while pressurizing and restraining the primary molding portion by the second cavity block 2. Next While filling the cavity for the molding part with the resin material and molding the secondary molding part, it is joined and integrated with the primary molding part,
And a step of obtaining a shape of a two-color resin molded product composed of these primary and secondary molding parts, wherein a region where the primary molding part is to be press-restrained by the second cavity block at the time of molding the secondary molding part. The width dimension W 11 of the pressure-restraining region is set to a value obtained by the following equation, with the boundary between the secondary molding portion as a reference and the width W 11 from the boundary. Method for molding a two-color resin molded product. W 11 = (T−S 2 б 2 ) / {L 1 Y (Δt 1 / t 1 )} L 1 : Length of projection surface of primary molding part S 2 : Projection area of secondary molding part T: Molding machine Clamping force t 1 : Plate thickness of primary molding part Δt 1 : Compression amount of primary molding part (empirical value) б 1 = Y (Δt 1 / t 1 ): Compressive stress of primary molding part б 2 : Secondary molding Molding pressure of the part S 11 = L 1 · W 11 : Optimum pressing area of the primary molding part
成形部とは異色の樹脂材料で成形される同じく断面略コ
字状の二次成形部とを、各成形部の一方の脚部の外側面
を接合面として接合一体化してなる二色樹脂成形品を成
形するにあたり、 コアブロックと第１のキャビティブロックとで形成され
る一次成形部用のキャビティに樹脂材料を充填して一次
成形部を成形したのちに、 前記一次成形部をコアブロック側に残したまま型開きし
て、前記第１のキャビティブロックに代えて第２のキャ
ビティブロックとコアブロックとを型締めすることによ
り、第２のキャビティブロックで一次成形部を加圧拘束
しながらこの第２のキャビティブロックとコアブロック
および一次成形部とで二次成形部用のキャビティを形成
し、 前記二次成形部用のキャビティに樹脂材料を充填して二
次成形部を成形しながら一次成形部と接合一体化して、
これら一次，二次成形部よりなる二色樹脂成形品形状を
得るようにした金型構造であって、 前記第２のキャビティブロックのうち一次成形部と二次
成形部との境界に沿う部分に、その境界から一次成形部
側にかけて所定の幅Ｗ11を有して且つ一次成形部に直接
接触して該一次成形部を加圧拘束する押圧部を形成し、 この押圧部の幅寸法Ｗ11を次式で求められる値に設定し
たことを特徴とする二色樹脂成形用の金型構造。 Ｗ11＝（Ｔ−Ｓ2б2）／｛Ｌ1Ｙ（Δｔ1／ｔ1）｝ Ｌ1：一次成形部の投影面の長さ Ｓ2：二次成形部の投影面積 Ｔ：成形機の型締め力 ｔ1：一次成形部の板厚 Δｔ1：一次成形部の圧縮量（経験値） б1＝Ｙ（Δｔ1／ｔ1）：一次成形部の圧縮応力 б2：二次成形部の成形圧力 Ｓ11＝Ｌ1・Ｗ11：一次成形部の最適加圧面積2. A primary molding part having a substantially U-shaped cross section and a secondary molding part having a substantially U-shaped cross-section molded from a resin material having a different color from that of the primary molding part. In molding a two-color resin molded product that is integrally joined with the outer surface of the leg as the bonding surface, the resin material is filled in the cavity for the primary molding part formed by the core block and the first cavity block. After molding the primary molding part, the mold is opened while leaving the primary molding part on the core block side, and the second cavity block and the core block are clamped in place of the first cavity block. The second cavity block, the core block, and the primary molding portion form a cavity for the secondary molding portion while pressurizing and restraining the primary molding portion with the second cavity block. While filling the vity with resin material and molding the secondary molding part, it is joined and integrated with the primary molding part,
A mold structure adapted to obtain a two-color resin molded product shape composed of these primary and secondary molding parts, wherein a part of the second cavity block along a boundary between the primary molding part and the secondary molding part is formed. A pressing portion having a predetermined width W 11 from the boundary to the primary forming portion side and directly contacting the primary forming portion to press and restrain the primary forming portion is formed, and a width dimension W 11 of the pressing portion is formed. A mold structure for two-color resin molding, wherein is set to a value obtained by the following formula. W 11 = (T−S 2 б 2 ) / {L 1 Y (Δt 1 / t 1 )} L 1 : Length of projection surface of primary molding part S 2 : Projection area of secondary molding part T: Molding machine Clamping force t 1 : Plate thickness of primary molding part Δt 1 : Compression amount of primary molding part (empirical value) б 1 = Y (Δt 1 / t 1 ): Compressive stress of primary molding part б 2 : Secondary molding Molding pressure of the part S 11 = L 1 · W 11 : Optimum pressing area of the primary molding part
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15079095A JPH091589A (en) | 1995-06-19 | 1995-06-19 | Method for molding of bicolor resin molded product and mold structure for molding of bicolor resin |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15079095A JPH091589A (en) | 1995-06-19 | 1995-06-19 | Method for molding of bicolor resin molded product and mold structure for molding of bicolor resin |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH091589A true JPH091589A (en) | 1997-01-07 |
Family
ID=15504497
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15079095A Pending JPH091589A (en) | 1995-06-19 | 1995-06-19 | Method for molding of bicolor resin molded product and mold structure for molding of bicolor resin |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH091589A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106863715A (en) * | 2017-03-10 | 2017-06-20 | 惠州市炬兴合实业有限公司 | A kind of double-color mold |
-
1995
- 1995-06-19 JP JP15079095A patent/JPH091589A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106863715A (en) * | 2017-03-10 | 2017-06-20 | 惠州市炬兴合实业有限公司 | A kind of double-color mold |
| CN106863715B (en) * | 2017-03-10 | 2022-12-23 | 深圳市荣晖旺塑胶电子有限公司 | Double-color mold |
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