JPH02196613A - Die for molding plastic - Google Patents

Die for molding plastic

Info

Publication number
JPH02196613A
JPH02196613A JP1595389A JP1595389A JPH02196613A JP H02196613 A JPH02196613 A JP H02196613A JP 1595389 A JP1595389 A JP 1595389A JP 1595389 A JP1595389 A JP 1595389A JP H02196613 A JPH02196613 A JP H02196613A
Authority
JP
Japan
Prior art keywords
molten resin
cavity
cylindrical member
mold
hole
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.)
Pending
Application number
JP1595389A
Other languages
Japanese (ja)
Inventor
Fumio Nogami
野上　文夫
Masahiro Yonezawa
米沢　正浩
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Electric Corp
Original Assignee
Mitsubishi Electric Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Mitsubishi Electric Corp filed Critical Mitsubishi Electric Corp
Priority to JP1595389A priority Critical patent/JPH02196613A/en
Publication of JPH02196613A publication Critical patent/JPH02196613A/en
Pending legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
    • B29C45/17—Component parts, details or accessories; Auxiliary operations
    • B29C45/46—Means for plasticising or homogenising the moulding material or forcing it into the mould
    • B29C45/56—Means for plasticising or homogenising the moulding material or forcing it into the mould using mould parts movable during or after injection, e.g. injection-compression moulding
    • B29C45/5675—Means for plasticising or homogenising the moulding material or forcing it into the mould using mould parts movable during or after injection, e.g. injection-compression moulding for making orifices in or through the moulded article

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Moulds For Moulding Plastics Or The Like (AREA)

Abstract

PURPOSE:To eliminate a weld line, to enhance strength, to hardly generate of a burr and deformation of a die resulting from excessive pressure and thereby to obtain the high-precision moldings by inserting a thin-walled cylindrical member into molten resin and forming a hole. CONSTITUTION:Molten resin is introduced into a cavity 25 through a sprue 13b. Such an obstruction that flow of molten resin is branched and thereafter made confluent is inexistent in the cavity 25 and therefore a weld line 3 is ungenerated. Molten resin is filled in the cavity 25 and thereafter a thin-walled cylindrical member 36 is forcedly inserted into molten resin by a pressing press 38. This cylindrical member is held in such a state that the tip part 36a has been allowed to abut against the top face 13a of the cavity until resin is solidified. In the meantime, a central push pin 32 is held by a holder 33 in the same position as a time for introducing molten resin. When molten resin has been completely solidified and thereafter the top force 13 is taken out, the part of the cylindrical part 36 is perforated to form a hole 2 and the moldings 1 are obtained.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 この発明は穴を有するプラスチック成形品を製造するプ
ラスチック成形用金型に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a plastic molding die for producing a plastic molded article having holes.

〔従来の技術〕[Conventional technology]

第４図は穴を有するプラスチック成形品（以下単に成形
品という）の−例を示す平面図である。FIG. 4 is a plan view showing an example of a plastic molded product having holes (hereinafter simply referred to as molded product).

図において、（１）は板状の成形品、（２）は成形品（
１）に設けられた円形の穴、（３）は成形時に発生する
ウェルドライン（詳細は後述）、（イ）はゲート部残存
部（後述）である、成形品（１）は例えばプラスチック
成形用金型（以下、単に金型という）を用いて射出成形
法により成形される。第５図は従来の金型を示す横断面
図であり、図において、（１１）は下型（１２）及び上
型（１３）で精成された割型の金型であり、下型（１２
）に設けられたキャビティ下面（１２ａ）と上型（１３
）に設けられたキャビティ上面（１３ａ）とにより構成
されて溶融樹脂が注入されて固化されるキャビティ（１
４）、穴（２）を形成するための円形の突出部（１２ｂ
）、樹脂を注入するためのスプール（１３ｂ）、スプー
ル（１３ｂ）とキャビティ（１４）とを連通するランナ
（１２ｃ）及びゲート（１２ｄ）が設けられている。In the figure, (1) is a plate-shaped molded product, and (2) is a molded product (
1) is a circular hole provided in 1), (3) is a weld line that occurs during molding (details will be described later), and (A) is the remaining part of the gate part (described later). Molded product (1) is, for example, used for plastic molding. It is molded by injection molding using a mold (hereinafter simply referred to as a mold). FIG. 5 is a cross-sectional view showing a conventional mold. In the figure, (11) is a split mold refined by a lower mold (12) and an upper mold (13), and the lower mold ( 12
) and the upper mold (13
) and a cavity upper surface (13a) provided in the cavity (13a) into which the molten resin is injected and solidified.
4), a circular protrusion (12b) for forming the hole (2)
), a spool (13b) for injecting resin, a runner (12c) and a gate (12d) that communicate the spool (13b) and the cavity (14).

次に、上記の金型（１１）を用いて成形品（１）を射出
成形する方法について説明する。溶融樹脂はプランジャ
（図示せず）によりスプール（１３ｂ）からランナ（１
２ｃ）、ゲート（１２ｄ）を経てキャビティ（１４）内
に高速高圧で注入（射出）されて、冷却固化後玉型（１
３）を下型（１２）から分離させて成形品（１）を取り
出す、取り出したｔ麦スプール（１３ｂ）及びランナ（
１２ｃ）部の固化した樹脂を折って取り除いた残り部分
がゲート部残存部（２）である、この場合、キャビティ
（１４）内に注入された樹脂は突出部（１２ｂ）により
２分された後合流してキャビティ（１４）内に満たされ
る。キャビティ（１４）内を分岐して流れた溶融樹脂は
合流するまでに放熱されて温度が低下しているため、合
流したときに完全には融合せず、第４図に示されるいわ
ゆるウェルドライン（３１が発生する。この現象は良く
知られたものであるが、樹脂の注入温度や金型温度が低
い場合あるいは穴（２）の径、すなわち突出部（１２ｂ
）の径が大きい場合に著しくなり、ウェルドライン（３
）部では成形品の強度低下が著しい、このようなウェル
ドライン（３）の発生を防止するために第６図に示す金
型（２１）が考えられる。第６図は金型の横断面図であ
り、図において、（２２）はキャビティ下面（２２ａ）
を有する下型、（２３）は成形品（１）の穴（２）に対
応する位置に設けられキャビティ上面（２３ａ）を有す
る円柱状の成型ビン、（２４）は成型ビン（２３）をキ
ャビティ（２５）に挿入するための油圧プレス、（２６
）は油圧プレス（２４）の基礎である。上記のように構
成された金型において、成形ビン（２３）の上面（２３
ａ）が下型（２２）のキャビティ下面（２２ａ）と同じ
位置に合わされた状態、すなわちキャビティ（２５）内
に障害物がない状態にて樹脂が注入され、注入されたキ
ャビティ（２５）内の溶融樹脂中に成形ビン（２３）が
油圧プレス（２４）により強制的に挿入される。この状
態で樹脂が固化後、キャビティ（２５）内に挿入されて
いた成型ビン（２３）を引き抜いて元の位置へ戻すこと
により成型ビン（２３）の挿入されていた部分が穴（２
）として形成される。この金型（２１）においては、溶
融樹脂がキャビティ（２５）内に注入されるときにキャ
ビティ（２５）内の溶融樹脂の流れが分岐される障害物
（第５図における突出部（１２ｂ）　）がないのでウェ
ルドライン（３）は発生しない。Next, a method of injection molding a molded article (1) using the above mold (11) will be explained. The molten resin is transferred from the spool (13b) to the runner (1) by a plunger (not shown).
2c), is injected (injected) into the cavity (14) through the gate (12d) at high speed and under high pressure, and after cooling and solidifying, the lens shape (1
3) from the lower mold (12) and take out the molded product (1).
The remaining part after breaking off and removing the solidified resin in section 12c) is the gate remaining part (2). In this case, the resin injected into the cavity (14) is divided into two parts by the protruding part (12b). They merge and fill the cavity (14). The molten resin that has branched and flowed inside the cavity (14) has radiated heat and lowered its temperature by the time it merges, so when it merges, it does not completely fuse, forming a so-called weld line (see FIG. 4). 31 occurs. This phenomenon is well known, but it can occur when the resin injection temperature or mold temperature is low, or when the diameter of the hole (2), that is, the protrusion (12b)
) becomes noticeable when the diameter of the weld line (3
In order to prevent the occurrence of such a weld line (3) where the strength of the molded product is significantly reduced at the portion ), a mold (21) shown in FIG. 6 can be considered. FIG. 6 is a cross-sectional view of the mold, and in the figure, (22) is the lower surface of the cavity (22a).
(23) is a cylindrical molding bottle provided at a position corresponding to the hole (2) of the molded product (1) and has a cavity upper surface (23a); (24) is a molding bottle (23) having a cavity. Hydraulic press for insertion into (25), (26
) is the basis of the hydraulic press (24). In the mold configured as described above, the upper surface (23
a) is aligned to the same position as the lower surface of the cavity (22a) of the lower mold (22), that is, with no obstruction in the cavity (25), the resin is injected, and the resin is injected into the injected cavity (25). A molding bottle (23) is forcibly inserted into the molten resin by a hydraulic press (24). After the resin solidifies in this state, the molded bottle (23) that was inserted into the cavity (25) is pulled out and returned to its original position, so that the part where the molded bottle (23) was inserted becomes the hole (2).
) is formed as. In this mold (21), there is an obstacle (the protrusion (12b) in FIG. 5) that branches the flow of the molten resin in the cavity (25) when the molten resin is injected into the cavity (25). Since there is no weld line (3), no weld line (3) occurs.

〔発明が解決しようとする課題〕[Problem to be solved by the invention]

従来の金型は以上のように構成されているので、注入さ
れた溶融樹脂の流れは成形品の穴（２）を形成するため
にキャビティ（１４）内に設けられた突出部（１２ｂ）
により分岐された後合流するためにウェルドライン（３
）が発生する。また、これを防止するために考案された
第６図に示される金型（２１）においては、油圧プレス
（２４）により溶融樹脂中に強制的に挿入される成型ビ
ン（２３）により押し退けられた樹脂は逃げ場がないの
でキャビティ（２５）からはみ出して成形品に大きな「
ばり」が発生し、又過大な圧力上昇により金型に変形が
生じるなどの問題点があった。Since the conventional mold is constructed as described above, the flow of the injected molten resin flows through the protrusion (12b) provided in the cavity (14) to form the hole (2) of the molded product.
A weld line (3
) occurs. In addition, in the mold (21) shown in FIG. 6 devised to prevent this, the molding bottle (23) that is forcibly inserted into the molten resin by the hydraulic press (24) displaces the mold. Since the resin has no place to escape, it protrudes from the cavity (25) and leaves a large """ in the molded product.
There were problems such as "burrs" were generated and the mold was deformed due to excessive pressure rise.

この発明は、上記のような問題点を解消するためになさ
れたもので、成形品にウェルドラインが発生するのを防
止でき、又「ばり」の発生や変形の少ない金型を得るこ
とを目的とする。さらに、より改良されて「ばり」や変
形が発生しないようにされた金型を得ることを目的とす
る。This invention was made to solve the above-mentioned problems, and aims to provide a mold that can prevent weld lines from forming on molded products and that is less likely to cause burrs or deformation. shall be. Furthermore, it is an object of the present invention to obtain a mold that is further improved and is prevented from causing "burrs" or deformation.

〔課題を解決するための手段〕[Means to solve the problem]

この発明に係る金型は、穴に対応する位置に中間部材及
びこの中間部材を取り囲んで薄肉の筒状部材を設けて、
上記薄肉の筒状部材がキャビティ内の溶融樹脂中に挿入
されて上記穴を形成しうるようにするとともに、成形中
上記中間部材は上記溶融樹脂の注入時と同じ位置に保持
されるようにしたものである。The mold according to the present invention includes an intermediate member at a position corresponding to the hole, and a thin cylindrical member surrounding the intermediate member,
The thin-walled cylindrical member is inserted into the molten resin in the cavity to form the hole, and the intermediate member is held at the same position during molding as when the molten resin is injected. It is something.

又、穴に対応する位置に移動又は変形可能な中間部材及
びこの中間部材を取り囲んで設けられキャビティ内の溶
融樹脂中に挿入されて上記穴を形成しうるようにされた
筒状部材を備え、この筒状部材が上記溶融樹脂中に挿入
されたとき上記移動又は変形可能な中間部材が移動又は
変形して上記溶融樹脂が上記キャビティ内から上記筒状
部材内に流入しうるようにしたものである。The method further includes an intermediate member that can be moved or deformed to a position corresponding to the hole, and a cylindrical member that is provided surrounding the intermediate member and that can be inserted into the molten resin in the cavity to form the hole, When the cylindrical member is inserted into the molten resin, the movable or deformable intermediate member moves or deforms so that the molten resin can flow into the cylindrical member from inside the cavity. be.

〔作　　用〕[For production]

この発明においては、キャビティ内の溶融樹脂中に挿入
されて穴を形成しうるようにされた薄肉の筒状部材が溶
融樹脂中に挿入されるようにされているので、押し退け
られる樹脂の量が少なく、「ばり」や過大圧力による金
型の変形を少なくすることができる。In this invention, a thin-walled cylindrical member that is inserted into the molten resin in the cavity to form a hole is inserted into the molten resin, so that the amount of resin that is displaced is reduced. It is possible to reduce mold deformation due to "burrs" and excessive pressure.

また、筒状部材が溶融樹脂中に挿入されたとき中間部材
が移動又は変形して上記筒状部材により押し退けられた
溶融樹脂がキャビティ内から上記筒状部材内へ流入しう
るようにされているので、「ばり」や過大圧力による変
形をなくすことができる。Further, when the cylindrical member is inserted into the molten resin, the intermediate member moves or deforms so that the molten resin displaced by the cylindrical member can flow into the cylindrical member from inside the cavity. Therefore, deformation caused by "burrs" and excessive pressure can be eliminated.

〔発明の実施例〕[Embodiments of the invention]

第１図は、この発明の一実施例を示すもので、（ａ）図
は溶融樹脂注入前の状態を示す金型の横断面図、（ｂ）
図は樹脂を注入した後薄肉の筒状部材がキャビティ内に
挿入された状態を示す横断面図である。これらの図にお
いて、（１２ｃ）〜（２６）は第６図の従来装置と同様
であるので説明を省略する。FIG. 1 shows an embodiment of the present invention, (a) is a cross-sectional view of the mold before injection of molten resin, (b)
The figure is a cross-sectional view showing a state in which a thin-walled cylindrical member is inserted into a cavity after resin is injected. In these figures, (12c) to (26) are the same as those in the conventional device shown in FIG. 6, so their explanation will be omitted.

（３１）は金型、（３２）は成形品（１）の穴（２）（
第４図）に対応する位置に設けられた中間部材、本例で
は平らな上面（３２ａ）を有する円板状の中押しビン、
（３３）は中押しビンの上面（３２ａ）をロッド（３３
ａ３を介して溶融樹脂の注入前、注入後すなわち成形中
を通じてキャビティの下面（２２ａ）とほぼ同じ位１に
保持する保持装置、（３４）は保持装置（３３）を介し
て中押しビン（３２）を図の上方、矢印（３５）の方向
に押すことができるようにされたシリンダロッドである
。　＜３６）は中押しビン（３２）を取り囲んで設けら
れ刃状円形の先端部（３６ａ）を有し外径が穴（２）の
内径と同じにされた薄肉の筒状部材であり、押し出しプ
レート（３７）を介して油圧プレス（３８）に接続され
ており、油圧プレス（３８）によりキャビティ（２５）
内の溶融樹脂中に強制的に挿入しうるようにされている
。(31) is the mold, (32) is the hole (2) of the molded product (1) (
An intermediate member provided at a position corresponding to FIG.
(33) connects the top surface (32a) of the medium press bottle to the rod (33).
A holding device (34) holds the molten resin at approximately the same level as the bottom surface (22a) of the cavity before and after injection, that is, during molding, through the holding device (33). This is a cylinder rod that can be pushed upward in the figure in the direction of arrow (35). <36) is a thin-walled cylindrical member provided surrounding the intermediate push bottle (32), has a blade-like circular tip (36a), and has an outer diameter the same as the inner diameter of the hole (2), and (37) to a hydraulic press (38), and the hydraulic press (38) is connected to the cavity (25).
It is designed so that it can be forcibly inserted into the molten resin inside.

次に動作について説明する。キャビティ（２５）内に樹
脂が注入される前は中押しビン（３２）の上面（３２ａ
）は第１図（ａ＞に示されるようにキャビティ下面（２
２ａ）とほぼ同レベルになる位置に保持装置（３３）に
より保持されており、薄肉の筒状部材（３６）の先端（
３６ａ）もこれとほぼ同レベルの位置に保たれている。Next, the operation will be explained. Before the resin is injected into the cavity (25), the upper surface (32a
) is the lower surface of the cavity (2) as shown in Figure 1 (a).
The holding device (33) holds the thin-walled cylindrical member (36) at a position that is approximately at the same level as 2a).
36a) is also maintained at approximately the same level.

この状態でスプール（１３ｂ）から溶融樹脂がキャビテ
ィ（２５）内に注入されるが、キャビティ（２５）内に
は溶融樹脂の流れを分岐させた後合流させるような障害
物がないのでウェルドライン（３）（第４図）は発生し
ない、キャビティ（２５）内に溶融樹脂が満たされた後
、キャビティ（２５）内の溶融樹脂中に薄肉の筒状部材
（３６）が油圧プレス（３８）により強制的に挿入され
その先端部（３６ａ）がキャビティ上面（１３ａ）に当
接した状態、すなわち（ｂ）図に示される状態で樹脂が
固化するまで保持される。In this state, the molten resin is injected into the cavity (25) from the spool (13b), but since there are no obstacles in the cavity (25) that would cause the flow of the molten resin to diverge and then merge, the weld line ( 3) (Fig. 4) does not occur. After the cavity (25) is filled with molten resin, the thin-walled cylindrical member (36) is pressed into the molten resin in the cavity (25) by the hydraulic press (38). It is forcibly inserted and held with its tip (36a) in contact with the cavity upper surface (13a), that is, in the state shown in Figure (b), until the resin solidifies.

この間、中押しビン（３２）は保持装置（３３）により
溶融樹脂の注入時と同じ位置に保持されている。注入樹
脂が完全に固化した後、上型（１３）を取り外すと筒状
部材（３６）の部分が穴ｔ２）（第４図）となり、成形
品（１）が得られる。筒状部材（３６）の内部の固化し
た樹脂は固定装置（３３）を介してシリンダロッド（３
４）により中押しビン（３２）を押すことにより筒状部
材（３６）の外へ容易に押し出して外すことができる。During this time, the intermediate push bottle (32) is held by the holding device (33) in the same position as when pouring the molten resin. After the injected resin has completely solidified, the upper mold (13) is removed, and the cylindrical member (36) becomes a hole t2) (FIG. 4), yielding the molded product (1). The solidified resin inside the cylindrical member (36) is transferred to the cylinder rod (3) via the fixing device (33).
4), by pushing the intermediate push bottle (32), it can be easily pushed out of the cylindrical member (36) and removed.

なお、本実施例では筒状部材の先端部（３６ａ）を刃状
としているが、他の形状であっても良い。In this embodiment, the tip (36a) of the cylindrical member has a blade shape, but it may have another shape.

第２図は他の実施例を示す横断面図で、（ａ）図は樹脂
を注入する前の状態、（ｂ）図は筒状部材が溶融樹脂中
に挿入された状態を示している０図において、（４１）
は金型、（４２）は穴（２）（第４図）に対応する位置
に設けられた中間部材である中押しビンであり、平らな
上面（４２ａ）を有し円板状の形状をしている。中押し
ビン（４２）は油圧シリンダ（４９）により支持されて
図の矢印（４５）の方向に自由に移動しうるようにされ
ている。　（４６）は中押しビン（４２）を取り囲んで
設けられ先端部（４６ａ）　、テーパ部（４６ｂ）を有
し外径が穴（２）の内径と同じにされた筒状部材であり
、本例では第１図の実施例より厚内とされている０以上
のように構成された金型（４１）において、中押しビン
（４２）の上面（４２ａ）及び筒状部材の先端部（４６
ａ）をキャビティ下面（２２ａ）とほぼ同じレベルに合
わせた状態ですなわち、第２図＜ａ＞に示される状態に
てキャビティ（２５）内に樹脂を注入し、続いてこの溶
融樹脂中に筒状部材（４６）が油圧プレス（３８）によ
り強制的に挿入される。FIG. 2 is a cross-sectional view showing another embodiment, in which (a) shows the state before resin is injected, and (b) shows the state in which the cylindrical member is inserted into the molten resin. In the figure, (41)
is a mold, and (42) is an intermediate push bottle which is an intermediate member provided at a position corresponding to the hole (2) (Fig. 4), and has a flat upper surface (42a) and a disk-like shape. ing. The intermediate pusher bottle (42) is supported by a hydraulic cylinder (49) so that it can move freely in the direction of the arrow (45) in the figure. (46) is a cylindrical member that is provided surrounding the intermediate press bottle (42), has a tip end (46a), a tapered part (46b), and has an outer diameter that is the same as the inner diameter of the hole (2). Now, in the mold (41) configured to have a thickness of 0 or more, which is considered to be within the thickness according to the embodiment shown in FIG.
Resin is injected into the cavity (25) in the state shown in FIG. The shaped member (46) is forcibly inserted by the hydraulic press (38).

このとき、中押しビン（４２）は油圧シリンダ（４９）
により第２図（ｂ）図に示される如く下方に移動され、
挿入された筒状部材（４６）により押し退けられた樹脂
は、キャビティ（２５）内から第２図（ｂ）の中押しビ
ンの上面（４２ａ）と−点鎖線で囲まれた部分（Ａ）へ
流入するようになっている。従って、部分（Ａ）の容積
を筒状部材（４６）が溶融樹脂中に挿入される部分の体
積と等しくなるようにすれば、「ばり」の発生を完全に
防止することが可能となる。なお、上記の金型（４１）
を使用して第１図の実施例と同様の手順にて成型品（１
）が製作されるが、円筒部材（４６）内で固化した樹脂
は油圧シリンダ（４９）により中押しビン（４２）を押
すことにより取り外すことができる。At this time, the middle push bottle (42) is connected to the hydraulic cylinder (49).
is moved downward as shown in FIG. 2(b),
The resin pushed away by the inserted cylindrical member (46) flows from the inside of the cavity (25) into the upper surface (42a) of the medium press bottle in FIG. 2(b) and the area (A) surrounded by the dashed line. It is supposed to be done. Therefore, by making the volume of the part (A) equal to the volume of the part where the cylindrical member (46) is inserted into the molten resin, it is possible to completely prevent the occurrence of "burrs". In addition, the above mold (41)
A molded product (1
) is manufactured, but the resin solidified within the cylindrical member (46) can be removed by pushing the intermediate push bottle (42) with a hydraulic cylinder (49).

なお、筒状部材（４６）のテーパ部（４６ｂ）は、筒状
部材（４６）が溶融樹脂中に強制的に挿入されるとき押
し退けられる溶融樹脂が筒状部材（４６）の内部へ流入
しやすくするために設けられたものであるが、不可欠な
ものではない。Note that the tapered portion (46b) of the cylindrical member (46) allows the molten resin that is pushed away when the cylindrical member (46) is forcibly inserted into the molten resin to flow into the interior of the cylindrical member (46). It is provided for convenience, but is not essential.

また、油圧シリンダ（４９）の油圧回路に例えばアキュ
ムレータを設けて筒状部材（４６）が溶融樹脂中に挿入
されたときのキャビティ（２５）内の圧力上昇により油
圧シリンダ（４９）が図の下方に押されて中押しビン（
４２）が図の下方に移動するようにしても良い。In addition, for example, an accumulator may be provided in the hydraulic circuit of the hydraulic cylinder (49), and the hydraulic cylinder (49) may move downward in the figure due to the pressure increase in the cavity (25) when the cylindrical member (46) is inserted into the molten resin. Press the middle push bottle (
42) may be moved downward in the figure.

第３図はさらに他の実施例を示す側断面図であり、穴（
２）に対応する位置に弾性を有する中間部材、例えばシ
リコンゴム製の円柱状のゴムブロック（５２）を設け、
このゴムブロック（５２）を取り囲んで比較的薄肉の筒
状部材（５６）を設け、油圧プレス（５８）により、筒
状部材（５６）をキャビティ（２５）内に挿入可能とし
たものである。このように構成された金型（５１）にお
いても、成形品（２）の製作については上述の各実施例
とほぼ同様であり、第３図（ａ）に示されるような筒状
部材（５６）の先端部（５６ｂ）、ゴムブロック（５２
）の上面（５２ａ）がほぼ同レベルの位置にある状態で
溶融樹脂の注入が行われ、筒状部材（５６）により押し
退けられるキャビティ（２５）内の溶融樹脂はゴムブロ
ック（５２）を圧縮する形で筒状部材（５６）の内部へ
流入する。すなわち、ゴムブロック（５２）は圧縮され
て第３図（ｂ）に示される状態となるが図の一点鎖線と
ゴムブロック（５２）の上面（５２ａ）とに囲まれた部
分（Ｂ）の容積が、筒状部材（５６）の溶融樹脂中に挿
入された部分の体積と等しくなるようにされている。FIG. 3 is a side sectional view showing still another embodiment, with holes (
An elastic intermediate member, such as a cylindrical rubber block (52) made of silicone rubber, is provided at a position corresponding to 2),
A relatively thin cylindrical member (56) is provided surrounding the rubber block (52), and the cylindrical member (56) can be inserted into the cavity (25) by a hydraulic press (58). In the mold (51) configured in this way, the production of the molded product (2) is almost the same as in each of the above embodiments, and the cylindrical member (56) as shown in FIG. 3(a) is used. ) tip (56b), rubber block (52
) The molten resin is injected with the upper surfaces (52a) of the two parts at approximately the same level, and the molten resin in the cavity (25), which is pushed away by the cylindrical member (56), compresses the rubber block (52). The liquid flows into the interior of the cylindrical member (56). That is, the rubber block (52) is compressed to the state shown in FIG. is made equal to the volume of the portion of the cylindrical member (56) inserted into the molten resin.

上述の各実施例においては成形品が穴を有する板状のも
のについて示したが、板状のものに限られるものではな
い、又、穴はボスに設けるものであっても良く、穴の形
状は四角形、孔型その他の形状であっても良く、筒状部
材の溶融樹脂中に挿入される部分の形状を適宜所望の形
状にすれば良い、又、射出成形法に限られず、トランス
ファ成形法、注型法その他の方法であっても同様の効果
を奏する。In each of the above embodiments, the molded product is plate-shaped with a hole, but the molded product is not limited to a plate-shaped product. Also, the hole may be provided in the boss, and the shape of the hole may be changed. may be rectangular, hole-shaped or other shapes, and the shape of the portion of the cylindrical member to be inserted into the molten resin may be suitably made into a desired shape.Also, it is not limited to injection molding, and transfer molding may be used. , casting method, and other methods have similar effects.

〔発明の効果〕〔Effect of the invention〕

以上のように、この発明によれば薄肉の筒状部材を溶融
樹脂中に挿入して穴を形成するようにしたので、ウェル
ドラインがなくて強度が高く、かつ「ばり」の発生や過
大圧力による金型の変形を少なくでき、精度の高い成形
品を得ることができる。As described above, according to the present invention, a thin-walled cylindrical member is inserted into the molten resin to form a hole, so there is no weld line and the strength is high, and there is no possibility of "burrs" occurring or excessive pressure. It is possible to reduce the deformation of the mold caused by molding, and it is possible to obtain molded products with high precision.

又、溶融樹脂中に挿入された筒状部材により押し退けら
れる溶融樹脂が筒状部材内に設けられた中間部材の移動
又変形により筒状部材内に流入しうるようにされている
ので、「ばり」のない精度の高い成形品を得ることがで
きる。Furthermore, since the molten resin pushed away by the cylindrical member inserted into the molten resin can flow into the cylindrical member by movement or deformation of the intermediate member provided within the cylindrical member, "burr" is prevented. It is possible to obtain molded products with high precision without "."

【図面の簡単な説明】[Brief explanation of the drawing]

第１図〜第３図は夫々この発明の一実施例を示す横断面
図、第４図はプラスチック成形品の一例を示す平面図、
第５図、第６図は夫々従来のプラスチック成形金型の一
例を示す横断面図である。 図において、（３１）、　（４１）、　（５１）は金型
、（２５）はキャビティ、（３２）、　（４２）は中押
しビン、（５２）はゴムブロック、（３３）は保持装置
、（３６）、　（４６）、　（５６）は筒状部材、（３
７）は押し出しプレート、（３８）、　（５８）は油圧
プレス、 （４９）は油圧シリンダである。 なお、 各図中同一符号は同−又は相当部分を示す。1 to 3 are cross-sectional views showing one embodiment of the present invention, and FIG. 4 is a plan view showing an example of a plastic molded product.
FIGS. 5 and 6 are cross-sectional views showing an example of a conventional plastic molding die, respectively. In the figure, (31), (41), (51) are the mold, (25) is the cavity, (32), (42) are the intermediate press bottles, (52) is the rubber block, (33) is the holding device, ( 36), (46), (56) are cylindrical members, (3
7) is an extrusion plate, (38) and (58) are hydraulic presses, and (49) is a hydraulic cylinder. Note that the same reference numerals in each figure indicate the same or equivalent parts.

Claims (2)

【特許請求の範囲】[Claims] （１）金型のキャビティ内に溶融樹脂を注入して穴を有
する成形品を成形するためのプラスチック成形金型にお
いて、上記穴に対応する位置に設けられた中間部材及び
この中間部材を取り囲んで設けられ上記キャビティ内の
溶融樹脂中に挿入されて上記穴を形成しうるようにされ
た薄肉の筒状部材を備え、上記中間部材は上記成形中上
記溶融樹脂の注入時と同じ位置に保持されていることを
特徴とするプラスチック成形用金型。(1) In a plastic mold for molding a molded product having holes by injecting molten resin into the cavity of the mold, an intermediate member provided at a position corresponding to the hole and surrounding this intermediate member is used. A thin-walled cylindrical member is provided and inserted into the molten resin in the cavity to form the hole, and the intermediate member is held at the same position during the molding as when the molten resin is injected. A plastic mold that is characterized by: （２）金型のキャビティ内に溶融樹脂を注入して穴を有
する成形品を成形するためのプラスチック成形金型にお
いて、上記穴に対応する位置に設けられた移動又は変形
可能な中間部材及びこの中間部材を取り囲んで設けられ
上記キャビティ内の溶融樹脂中に挿入されて上記穴を形
成しうるようにされた筒状部材を備え、上記中間部材は
上記筒状部材が上記溶融樹脂中に挿入されたとき移動又
は変形して上記溶融樹脂が上記キャビティ内から上記筒
状部材内に流入しうるようにされていることを特徴とす
るプラスチック成形用金型。(2) In a plastic mold for molding a molded product having holes by injecting molten resin into the cavity of the mold, a movable or deformable intermediate member provided at a position corresponding to the hole; A cylindrical member is provided surrounding the intermediate member and is inserted into the molten resin in the cavity to form the hole, and the intermediate member is provided with the cylindrical member inserted into the molten resin. A mold for plastic molding, characterized in that the mold moves or deforms when the molten resin is moved or deformed so that the molten resin can flow into the cylindrical member from inside the cavity.
JP1595389A 1989-01-25 1989-01-25 Die for molding plastic Pending JPH02196613A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1595389A JPH02196613A (en) 1989-01-25 1989-01-25 Die for molding plastic

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1595389A JPH02196613A (en) 1989-01-25 1989-01-25 Die for molding plastic

Publications (1)

Publication Number Publication Date
JPH02196613A true JPH02196613A (en) 1990-08-03

Family

ID=11903115

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1595389A Pending JPH02196613A (en) 1989-01-25 1989-01-25 Die for molding plastic

Country Status (1)

Country Link
JP (1) JPH02196613A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013163269A (en) * 2012-02-09 2013-08-22 Honda Motor Co Ltd Injection molding die and injection molding method

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013163269A (en) * 2012-02-09 2013-08-22 Honda Motor Co Ltd Injection molding die and injection molding method

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