JPH05116160A

JPH05116160A - Sealing structure of foaming resin mold

Info

Publication number: JPH05116160A
Application number: JP3306511A
Authority: JP
Inventors: Kazuaki Kajitani; 二昭梶谷; Isao Hida; 功肥田
Original assignee: Aisin Takaoka Co Ltd; Toyota Motor Corp
Current assignee: Aisin Takaoka Co Ltd; Toyota Motor Corp
Priority date: 1991-10-25
Filing date: 1991-10-25
Publication date: 1993-05-14

Abstract

PURPOSE:To prevent the flash of a molded article from developing by improving the sealing properties of the mating surfaces of a foaming resin mold. CONSTITUTION:Lip-like sealing members 9 and 10, which are made of elastic body, are provided around the peripheral edge part on the cavity B side of the mating surfaces of an upper mold 7 and of a lower mold 8. Firstly, a foaming resin such as polyurethane or the like is poured in a cavity B under the condition that the upper mold 7 and the lower mold 8 are opened. Next, the upper mold 7 and the lower mold 8 are clamped together at the predetermined interval D between them so as to seal the mating surfaces 9 and 10 into close contact with each other. At this time, as being elastic body, the sealing members 9 and 10 deflect so as to elastically come into close contact with each other and the unevenness and dimensional tolerance of the close contacting parts are absorbed. As the foaming in the cavity B proceeds, the sealing members 9 and 10 are further strongly pushed against each other so as to come into close contact with each other by the foaming pressure acting on the relative rear face sides of the close contacting parts of the members, resulting in surely sealing the mating surfaces.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、発泡樹脂成形金型の上
型と下型との合せ面のシール構造に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing structure for a mating surface between an upper die and a lower die of a foamed resin molding die.

【０００２】[0002]

【従来の技術】従来、ポリウレタン等の発泡性樹脂を成
形して自動車のシートパッド等を製造する場合、図３に
示すような発泡樹脂成形金型１が用いられている。この
発泡樹脂成形金型１は、発泡性樹脂を充填するためのキ
ャビティＡを形成する上型２および下型３からなり、上
型２と下型３との合せ面には、発泡性樹脂の侵入を防ぐ
ためにシール部材４が介装されている。シール部材４
は、ゴム等の弾性体からなり、通常、下型３の合せ面
に、キャビティを囲む形に形成された溝５に嵌合されて
下型３側に取付けられている。2. Description of the Related Art Conventionally, when a foamable resin such as polyurethane is molded to manufacture an automobile seat pad or the like, a foamed resin molding die 1 as shown in FIG. 3 has been used. This foamed resin molding die 1 is composed of an upper mold 2 and a lower mold 3 that form a cavity A for filling the foamable resin, and the mating surface between the upper mold 2 and the lower mold 3 is made of the foamable resin. A seal member 4 is interposed to prevent entry. Seal member 4
Is made of an elastic material such as rubber, and is normally fitted to the mating surface of the lower mold 3 in a groove 5 formed to surround the cavity and attached to the lower mold 3 side.

【０００３】そして、上型２と下型３とを型締めしたと
き、シール部材４が上型２の合せ面に押付けられ、変形
して合せ面をシールするようになっている。When the upper die 2 and the lower die 3 are clamped, the seal member 4 is pressed against the mating surface of the upper die 2 and deforms to seal the mating surface.

【０００４】ところで、上型２と下型３との合せ面のシ
ールが不充分であると、成形時に合せ面に発泡性樹脂が
侵入して成形品にバリが発生する。そこで、シール性を
向上させるために、一般にアルミ鋳物である上型２およ
び下型３は、互いの合せ面が放電加工により平坦に加工
されており、また、下型３の溝５は、ＮＣ工作機により
精密に加工されている。By the way, if the sealing between the mating surfaces of the upper mold 2 and the lower mold 3 is insufficient, the foaming resin penetrates into the mating surfaces during molding, and burrs are generated on the molded product. Therefore, in order to improve the sealing property, the upper mold 2 and the lower mold 3, which are generally aluminum castings, have their mating surfaces flattened by electric discharge machining, and the groove 5 of the lower mold 3 has an NC shape. Precisely processed by machine tools.

【０００５】[0005]

【発明が解決しようとする課題】しかしながら、上記従
来の発泡成形金型１では、次のような問題がある。すな
わち、上型２および下型３の合せ面を完全に平坦に仕上
げることは困難であり、実際には部分的に僅かな凹凸が
生じる。また、成形品の形状が複雑な場合、溝５の形状
が複雑になるので、溝５に取付けられるシール部材４の
突出代が均一となりにくく、上型２との当接が均一にな
りにくい。その結果、シールが不充分となり、成形品に
バリが発生するという問題がある。また、型締の荷重を
大きくすることによりシール性を高めることができる
が、そのためには、金型の剛性を高める必要があり、上
型２および下型３の体積および重量が大きくなるので成
形時の熱効率が低下するという問題を生じる。However, the conventional foam molding die 1 has the following problems. That is, it is difficult to finish the mating surfaces of the upper mold 2 and the lower mold 3 completely flat, and in reality, slight unevenness is locally generated. Further, when the shape of the molded product is complicated, the shape of the groove 5 becomes complicated, so that the protrusion margin of the seal member 4 attached to the groove 5 is difficult to be uniform and the contact with the upper mold 2 is not uniform. As a result, there is a problem that the seal becomes insufficient and burrs are generated on the molded product. Further, the sealing performance can be improved by increasing the mold clamping load, but for that purpose, it is necessary to increase the rigidity of the mold, and the volume and weight of the upper mold 2 and the lower mold 3 become large. There is a problem that the thermal efficiency at the time decreases.

【０００６】また、発泡樹脂成形において、バリの発生
を防止することは重要な課題であり、この分野に関する
先行技術として実開昭５９−１９２３１７号、実開昭６
１−１７５４３４号等がある。Further, in the foaming resin molding, it is an important subject to prevent the generation of burrs, and as prior arts in this field, JP-A-59-192317 and JP-A-6-192.
1-175434 and the like.

【０００７】本発明は、以上の点に鑑みてなされたもの
であり、発泡樹脂成形金型の合せ面のシール性を向上さ
せてバリの発生を防止することを目的とする。The present invention has been made in view of the above points, and it is an object of the present invention to improve the sealing property of the mating surface of the foaming resin molding die and prevent the occurrence of burrs.

【０００８】[0008]

【課題を解決するための手段】本発明の発泡樹脂成形金
型のシール構造は、上記の課題を解決するために、上型
および下型の合せ面のキャビティ側周縁部に、内周側が
前記キャビティ側に延出された弾性体からなるリップ状
のシール部材を周設し、前記上型および下型が型締位置
にあるとき、前記上型側と下型側のシール部材の内周側
が互いに密着するようにしたことを特徴とする。In order to solve the above problems, the sealing structure for a foamed resin molding die of the present invention has the inner peripheral side at the cavity side peripheral portion of the mating surfaces of the upper die and the lower die. A lip-shaped seal member made of an elastic body extending to the cavity side is provided around, and when the upper mold and the lower mold are at the mold clamping position, the inner peripheral sides of the upper mold side and the lower mold side seal members are The feature is that they are in close contact with each other.

【０００９】[0009]

【作用】このように構成したことにより、キャビティ内
で上型側のシール部材と下型側のシール部材とが互いに
弾性的に密着するので、シール部材間に隙間が生じにく
く、また、成形時のキャビティ内の発泡圧力によって上
型側のシール部材と下型側のシール部材とが押付けられ
るので高いシール性を得ることができる。With this construction, the upper mold side seal member and the lower mold side seal member are elastically brought into close contact with each other in the cavity, so that a gap is unlikely to occur between the seal members, and at the time of molding. Since the upper mold side seal member and the lower mold side seal member are pressed by the foaming pressure in the cavity of 1, the high sealability can be obtained.

【００１０】[0010]

【実施例】以下、本発明の一実施例を図面に基づいて詳
細に説明する。図１は、本実施例に係る発泡樹脂成形金
型の縦断面図であり、図２は、図１の要部の拡大図であ
る。また、図１および図２は、発泡が完了して発泡樹脂
が金型のキャビティ内に充満した状態を示している。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a vertical cross-sectional view of a foamed resin molding die according to this embodiment, and FIG. 2 is an enlarged view of a main part of FIG. 1 and 2 show a state in which the foaming is completed and the foamed resin is filled in the cavity of the mold.

【００１１】図１および図２に示すように、発泡樹脂成
形金型６は、キャビティＢを形成する凹部7a，8aが設け
られた上型７と下型８とから構成されている。上型７お
よび下型８には、それぞれ互いの合せ面の凹部7a，8aの
周縁部に弾性体からなるシール部材９，10が周設されて
いる。このシール部材９，10は、例えば、適当な硬度を
有するゴム板等の弾性部材より、一定の幅の帯状体でキ
ャビティＢを囲む形にに打抜いて製作するか、あるい
は、さらにこの内周側を一方向に張出した形に成形して
製作する。As shown in FIGS. 1 and 2, the foamed resin molding die 6 is composed of an upper die 7 and a lower die 8 provided with concave portions 7a, 8a forming a cavity B. The upper mold 7 and the lower mold 8 are provided with sealing members 9 and 10 made of an elastic body around the peripheral portions of the recesses 7a and 8a of the mating surfaces. The sealing members 9 and 10 are manufactured by, for example, punching an elastic member such as a rubber plate having an appropriate hardness into a shape that surrounds the cavity B with a band-shaped body having a constant width, or by further forming the inner circumference thereof. It is manufactured by molding the side in one direction.

【００１２】上型７側のシール部材９は、その外周側が
合せ面の凹部7aの周縁部に固定されており、その内周側
がキャビティＢ側の下方に向かって延出するリップ状に
形成されている。また、下型８側のシール部材10は、そ
の外周側が合わせ面の凹部8aの周縁部に固定されてお
り、その内周側がキャビティＢ側の上方に向かって延出
するリップ状に形成されている。そして、図に示すよう
に、上型７と下型８とを型締することにより、上型７側
のシール部材９の下端部と下型８側のシール部材10の上
端部とがキャビティＢ内において互いに当接して撓んで
弾性的に密着するようになっている。The outer peripheral side of the seal member 9 on the upper die 7 side is fixed to the peripheral edge of the concave portion 7a of the mating surface, and the inner peripheral side thereof is formed in a lip shape extending downward toward the cavity B side. ing. The outer peripheral side of the seal member 10 on the lower die 8 side is fixed to the peripheral edge of the concave portion 8a of the mating surface, and the inner peripheral side thereof is formed in a lip shape extending upward toward the cavity B side. There is. Then, as shown in the drawing, by clamping the upper mold 7 and the lower mold 8, the lower end of the seal member 9 on the upper mold 7 side and the upper end of the seal member 10 on the lower mold 8 side are cavities B. Inside, they abut each other and bend to elastically adhere to each other.

【００１３】なお、上型７および下型８は、図示しない
型締装置に装着されており、型締時にシール部材９，10
が適度に撓んで所望の密着力が得られるように互いの合
わせ面の間に所定の隙間Ｄをもって型締されるようにな
っている。The upper mold 7 and the lower mold 8 are mounted on a mold clamping device (not shown), and sealing members 9 and 10 are used during mold clamping.
Are clamped with a predetermined gap D between their mating surfaces so that they can be appropriately bent to obtain a desired adhesion.

【００１４】以上のように構成した本実施例の作用につ
いて次に説明する。先ず、上型７と下型８とを開いた状
態でキャビティＢ内にポリウレタン等の発泡性樹脂を注
入する。次に、上型７と下型８とを型締してシール部材
９とシール部材10とを密着させ上型７と下型８との合わ
せ面のシールを行う。このとき、シール部材９とシール
部材10とは弾性体であるため、互いに当接することによ
り撓んで弾性的に密着するので、当接部の凹凸および寸
法公差が吸収されて、型締力を大きくすることなく充分
なシールを行うことができる。The operation of this embodiment having the above-mentioned structure will be described below. First, a foaming resin such as polyurethane is injected into the cavity B with the upper mold 7 and the lower mold 8 opened. Next, the upper mold 7 and the lower mold 8 are clamped to bring the seal member 9 and the seal member 10 into close contact with each other to seal the mating surface of the upper mold 7 and the lower mold 8. At this time, since the seal member 9 and the seal member 10 are elastic bodies, the seal members 9 and 10 bend and elastically adhere to each other when they come into contact with each other. It is possible to perform sufficient sealing without performing

【００１５】キャビティＢ内にて発泡が進むと、図２に
示すように、シール部材９および10は、互いの当接部の
背面側に作用する発泡圧Ｐにより、さらに強く押付けら
れて密着し、確実なシールを行うことができる。As the foaming proceeds in the cavity B, as shown in FIG. 2, the sealing members 9 and 10 are further strongly pressed and brought into close contact with each other by the foaming pressure P acting on the back side of the abutting portions thereof. Therefore, reliable sealing can be performed.

【００１６】発泡が終了して成形品が硬化した後、上型
７と下型８とを開いて成形品を取り出す。なお、キャビ
ティＢ内でシールを行っているので、シール部に僅かな
バリが発生しても、成形品の外側に突出しないので取除
く必要がない。After the foaming is completed and the molded product is cured, the upper mold 7 and the lower mold 8 are opened and the molded product is taken out. Since the sealing is performed in the cavity B, even if a slight burr is generated in the sealing portion, it does not need to be removed because it does not project to the outside of the molded product.

【００１７】[0017]

【発明の効果】以上、詳述したように、本発明の発泡樹
脂成形金型のシール構造によれば、上型側のシール部材
と下型側のシール部材とがキャビティ内で互いに密着す
るので、シール部材間に隙間が生じにくく、また、成形
時のキャビティ内の発泡圧によってシール部材どうしが
押付けられるので高いシール性を得ることができる。そ
の結果、成形時の金型の合せ面への発泡性樹脂の侵入を
なくし、バリの発生を防止することができる。さらに、
キャビティ内でシールを行っているので、シール部に僅
かなバリが発生しても、成形品の外側に突出しないので
取除く必要がない。また、上型と下型との合せ面によっ
て直接シールを行わないので合せ面に高精度の加工が不
要であり金型の製造コストを低くすることができる。さ
らに、型締力が比較的小さくてすむので、金型の体積お
よび重量が小さくてすみ、金型の製造コストを低くする
ことができるとともに熱効率を向上させることができる
という優れた効果を奏する。As described above in detail, according to the sealing structure of the foamed resin molding die of the present invention, the upper mold side sealing member and the lower mold side sealing member are in close contact with each other in the cavity. A gap is unlikely to be formed between the seal members, and the seal members are pressed against each other by the foaming pressure in the cavity during molding, so that high sealability can be obtained. As a result, it is possible to prevent the foaming resin from entering the mating surface of the mold at the time of molding and prevent the occurrence of burrs. further,
Since sealing is performed in the cavity, even if a slight burr is generated in the sealing portion, it does not need to be removed because it does not protrude to the outside of the molded product. Further, since the mating surfaces of the upper die and the lower die do not directly seal, the mating surfaces do not need to be processed with high precision, and the manufacturing cost of the die can be reduced. Furthermore, since the mold clamping force is relatively small, the volume and weight of the mold can be small, and it is possible to reduce the manufacturing cost of the mold and to improve the thermal efficiency.

【図面の簡単な説明】[Brief description of drawings]

【図１】本発明の一実施例の縦断面図である。FIG. 1 is a vertical sectional view of an embodiment of the present invention.

【図２】図１の装置の要部の拡大図である。FIG. 2 is an enlarged view of a main part of the apparatus shown in FIG.

【図３】従来の発泡樹脂成形金型の縦断面図である。FIG. 3 is a vertical sectional view of a conventional foamed resin molding die.

【符号の説明】[Explanation of symbols]

６発泡樹脂成形金型７上型８下型９，10 シール部材Ｂキャビティ 6 Mold for foaming resin 7 Upper mold 8 Lower mold 9,10 Seal member B Cavity

Claims

【特許請求の範囲】[Claims]

【請求項１】上型および下型の合せ面のキャビティ側
周縁部に、内周側が前記キャビティ側に延出された弾性
体からなるリップ状のシール部材を周設し、前記上型お
よび下型が型締位置にあるとき、前記上型側と下型側の
シール部材の内周側が互いに密着するようにしたことを
特徴とする発泡樹脂成形金型のシール構造。1. A lip-shaped seal member made of an elastic body, the inner peripheral side of which extends toward the cavity, is provided around the cavity-side peripheral portions of the mating surfaces of the upper die and the lower die, and the upper die and the lower die. A sealing structure for a foamed resin molding die, wherein the inner peripheral sides of the upper and lower mold sealing members are in close contact with each other when the mold is in the mold clamping position.