JP2867864B2 - Molding method of hollow molded body - Google Patents

Molding method of hollow molded body

Info

Publication number
JP2867864B2
JP2867864B2 JP5345469A JP34546993A JP2867864B2 JP 2867864 B2 JP2867864 B2 JP 2867864B2 JP 5345469 A JP5345469 A JP 5345469A JP 34546993 A JP34546993 A JP 34546993A JP 2867864 B2 JP2867864 B2 JP 2867864B2
Authority
JP
Japan
Prior art keywords
parison
mold
blow
molding
hollow
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
Application number
JP5345469A
Other languages
Japanese (ja)
Other versions
JPH07178710A (en
Inventor
清 高田
大介 越智
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.)
SUMITOMO JUKIKAI CHUTAN KK
Original Assignee
SUMITOMO JUKIKAI CHUTAN KK
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 SUMITOMO JUKIKAI CHUTAN KK filed Critical SUMITOMO JUKIKAI CHUTAN KK
Priority to JP5345469A priority Critical patent/JP2867864B2/en
Publication of JPH07178710A publication Critical patent/JPH07178710A/en
Application granted granted Critical
Publication of JP2867864B2 publication Critical patent/JP2867864B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B28—WORKING CEMENT, CLAY, OR STONE
    • B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
    • B28B11/00—Apparatus or processes for treating or working the shaped or preshaped articles
    • B28B11/003—Apparatus or processes for treating or working the shaped or preshaped articles the shaping of preshaped articles, e.g. by bending
    • B28B11/008—Blow moulding, e.g. with or without the use of a membrane

Landscapes

  • Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Moulds, Cores, Or Mandrels (AREA)

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【０００１】[0001]

【産業上の利用分野】この発明は、アルミナ系、ジルコ
ニア系等のセラミックス粉末、或は、金属粉末等の成形
方法、殊に、小口径・大胴径の中空成形体の成形方法に
関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a ceramic powder such as an alumina-based or zirconia-based powder or a metal powder, and more particularly to a method for forming a small-sized or large-diameter hollow molded body. is there.

【０００２】[0002]

【従来の技術】従来、セラミックス粉末、或は、金属粉
末等による小口径・大胴径の中空成形体、殊に、離型時
に中子と成形品とが干渉する所謂、アンダーカット部を
有するの成形体の成形では、中子の抜き取りが困難であ
るから、中子の要らない泥奨鋳込み法、或は、蝋等の可
溶性中子を使用した射出成形法等による成形が一般的に
広く採用されている。2. Description of the Related Art Conventionally, a hollow body having a small diameter and a large body diameter made of a ceramic powder or a metal powder, particularly a so-called undercut portion in which a core and a molded product interfere with each other during release. It is difficult to remove the core in the molding of the molded body of (1), so molding by a mud casting method that does not require a core, or an injection molding method using a soluble core such as wax is generally widely used. Has been adopted.

【０００３】ところが、周知の如く、泥奨鋳込み法は、
粉末セラミックス等を溶媒液に懸濁させて流動性を持っ
た泥奨とし、この泥奨を製品の形状に合わせて形成した
所望のキャビテイを有する石膏型等の吸水性鋳型に流し
込んで目的とする形状のセラミックス成形品を成形する
方法であるが、この泥奨鋳込み法は鋳型の吸水性を利用
して成形するために成形速度が遅いと共に、成形品の肉
厚のバラツキも大きく、工業的に均質の製品を多量生産
する方法としては不適当で、工芸的な花瓶等、一部の限
られた製品の製造に実用化されているに過ぎない。However, as is well known, the mud casting method is
Powder ceramics and the like are suspended in a solvent solution to obtain a fluid mud, and the mud is poured into a gypsum mold or other water-absorbent mold having a desired cavity formed according to the shape of the product. This is a method of molding a ceramic molded product with a shape, but this mud casting method uses the water absorption of the mold to form the product, and the molding speed is slow, and the thickness of the molded product varies greatly. It is not suitable as a method for mass-producing homogeneous products, and is only practically used for the production of some limited products such as craft vases.

【０００４】なお、前記泥奨鋳込み法の改良案として、
特開昭６２−９９１０号に開示されているように、泥奨
鋳込み後、鋳型から成形品を離型する前にキャビテイ内
に伸縮自在の袋を挿入して、該袋を介して成形品を内面
から加圧して成形品の肉厚を一定にする方法も提案され
てはいる。この改良案によれば、従来の泥奨鋳込み法に
比較して成形品の肉厚の一定化、及び、成形品内面の鋳
肌の滑らかさ等は向上するものの、基本的には泥奨鋳込
み法の域を出るものではなく、生産工程が増加する分、
更に生産性は低下し、工業的に利用する上には難があ
る。[0004] As an improvement of the above-mentioned mud casting method,
As disclosed in JP-A-62-9910, an extensible bag is inserted into a cavity after mud casting and before the molded product is released from the mold, and the molded product is inserted through the bag. A method of applying a pressure from the inner surface to keep the thickness of the molded article constant has also been proposed. According to this improvement plan, although the thickness of the molded product is made constant and the smoothness of the casting surface on the inner surface of the molded product is improved as compared with the conventional mud casting method, basically, the mud casting method is basically used. It is not out of the area of the law, but as the production process increases,
Further, productivity is reduced, and there is difficulty in industrial use.

【０００５】また、可溶性中子を使用した射出成形法に
おいては、高速成形が可能な射出成形法を使用するた
め、成形自体の高速化が可能であると共に、中子によっ
てキャビテイ形状を規制しているので、成形品の肉厚の
バラツキも少ない成形品の成形が可能であるが、可溶性
の中子を使用するために成形後、成形品を加熱して中子
を溶解して取り出さなければならず中子の取り出しに手
間が掛かると共に、中子取り出し時の加熱により中子が
膨張して製品に割れが発生したり、中子となる蝋等を消
耗品として使用するためコスト高となる等の不具合があ
った。In addition, in the injection molding method using a soluble core, since the injection molding method capable of high-speed molding is used, the molding speed can be increased, and the cavity shape is regulated by the core. Therefore, it is possible to mold a molded product with less variation in the thickness of the molded product.However, in order to use a soluble core, after molding, the molded product must be heated to dissolve the core and take it out. It takes time and effort to remove the core, and the core expands due to heating during core removal, causing cracks in the product, and costs increase due to the use of core wax and other consumables. There was a problem.

【０００６】一方、プラスチック ボトル等の成形に広
く利用され周知の方法として、吹き込み（ブロー）成形
法も公知である。この吹き込み（ブロー）成形法は、熱
可塑性合成樹脂を押し出し成形機によって可塑化・混練
した後、中空パリソンとして押し出し、該中空パリソン
を吹き込み成形用割型に挿入して、エアーブローによっ
て前記中空パリソンを膨らませて吹き込み成形用割型に
形成したキャビテイ形状に合った成形品を成形する方法
であり、中子を使用する必要もなく、比較的簡単な方法
によりボトル等の小口径・大胴径の容器であっても大量
に生産することができる。On the other hand, as a widely used and well-known method for molding plastic bottles and the like, a blow molding method is also known. In the blow (blow) molding method, a thermoplastic synthetic resin is plasticized and kneaded by an extruder, extruded as a hollow parison, and the hollow parison is inserted into a blow mold split mold, and the hollow parison is blown by air blow. Is a method of forming a molded product that fits the cavity shape formed into a blow mold splitting mold by blowing it, without using a core, and by using a relatively simple method with a small diameter and large body diameter such as a bottle. Even containers can be mass-produced.

【０００７】しかしながら、この吹き込み（ブロー）成
形法によつて、延性の無い無機質のセラミックス粉末、
或は、金属粉末製のパリソンを吹き込み成形しようとし
た場合、パリソンが延びないため図８に示すように吹き
破れてしまって成形することができない。このため、吹
き込み成形法による成形は、有機質の高分子化合物等に
より形成したパリソンのように、エアーブロー時にパリ
ソンが吹き破けることなく膨張し、冷却によって膨張し
た形状をそのままの形で固定できるものに限られ、主と
して、プラスチック性ボトルの成形に使用される以外、
他の用途には殆ど使用されていないのが実情である。However, by this blow molding method, non-ductile inorganic ceramic powder,
Alternatively, when a parison made of metal powder is blown and formed, the parison does not extend, so that the parison blows out as shown in FIG. 8 and cannot be formed. For this reason, the molding by the blow molding method is such that the parison expands without being blown off during air blowing, such as a parison formed of an organic polymer compound, and the shape expanded by cooling can be fixed as it is. Limited to, mainly used for molding plastic bottles,
In fact, it is hardly used for other purposes.

【０００８】[0008]

【発明が解決しようとする課題】本発明は、延性の無い
セラミックス粉末、或は、金属粉末等によって、小口径
・大胴径の成形品を成形するに当たり、従来の泥奨鋳込
み法による否生産性及び品質のバラツキ、或は、可溶性
中子を使用した射出成形法による高コスト、等の不具合
を解消し、簡易で、しかも、工業的に均質の成形品の生
産が可能な小口径・大胴径の中空成形品の成形が可能な
手段はないものかと種々思考し、吹き込み成形法に着目
し、本来、吹き込み成形法には適さないとされていた粉
末のセラミックス、或は、金属等の成形品の成形を吹き
込み成形法よつて可能にすることを目的とするものであ
る。SUMMARY OF THE INVENTION The present invention relates to a method for molding a small-diameter and large-diameter molded product using a non-ductile ceramic powder or a metal powder by using a conventional mud casting method. It eliminates problems such as variations in properties and quality, or high costs due to the injection molding method using a soluble core, etc., and enables simple and industrially uniform molded products of small diameter and large diameter. Various thoughts on whether there is a means that can form a hollow molded product with a body diameter, and paying attention to the blow molding method, powder ceramics, which were originally not suitable for the blow molding method, or metal, etc. It is an object of the present invention to enable molding of a molded article by a blow molding method.

【０００９】[0009]

【課題を解決するための手段】本発明によれば、押し出
し成形機によって粉末のセラミックス、或は、金属とバ
インダとの混合物を混練して押し出し、円筒状の中空パ
リソンを成形し、該中空パリソンを吹き込み成形用割型
に挿入した後、吹き込み成形用割型を型閉じし、望まし
くは、前記中空パリソンの外側にゴム等の弾性材を設
け、吹き込み成形用割型（キャビティ）内をパリソンの
内側よりやや低圧に保持して前記中空パリソンに内外両
面から肉厚方向の加圧力を付加し、前記型閉じした吹き
込み成形用割型内を徐々に減圧しながら前記中空パリソ
ン内にゴム等の弾性材を介して加圧流体を吹き込み、膨
張させて成形した後、型開きして離型することを特徴と
する中空成形体の成形方法が得られる。According to the present invention, a powdery ceramic or a mixture of a metal and a binder is kneaded and extruded by an extruder to form a cylindrical hollow parison. After being inserted into the blow molding split mold, the blow molding split mold is closed, and preferably, an elastic material such as rubber is provided outside the hollow parison, and the inside of the blow molding split mold (cavity) is formed by the parison. While maintaining the pressure slightly lower than the inner side, a pressing force in the thickness direction is applied to the hollow parison from both the inner and outer surfaces, and while the inside of the closed mold for blow molding is gradually reduced in pressure, the elasticity of rubber or the like is filled in the hollow parison. A method for molding a hollow molded article is obtained, in which a pressurized fluid is blown through a material, expanded and molded, then the mold is opened and the mold is released.

【００１０】[0010]

【作用】押し出し成形機によって、混練した粉末のセラ
ミックス、或は、金属とバインダとの混合物を混練し、
円筒状の中空パリソンとして押し出し、吹き込み成形用
割型に挿入して、該吹き込み成形用割型を型閉じして、
前記中空パリソン内にゴム等の弾性材を介して加圧流体
を吹き込むから、パリソンは弾性材の表面に付着した状
態で弾性材の変形（膨張）によって弾性材と同一形状に
変形する。この際、パリソンには弾性材を介して平均化
された加圧力が均一に作用するので、加圧力が局部的に
集中してかかることはないから延性の無いパリソンであ
っても吹き破れを生じることはない。The kneaded powder ceramic or the mixture of metal and binder is kneaded by an extruder,
Extruded as a cylindrical hollow parison, inserted into the blow mold split mold, closing the blow mold split mold,
Since the pressurized fluid is blown into the hollow parison through an elastic material such as rubber, the parison is deformed into the same shape as the elastic material by the deformation (expansion) of the elastic material while being attached to the surface of the elastic material. At this time, the pressing force averaged via the elastic material uniformly acts on the parison, so that the pressing force does not concentrate locally, so even the non-ductile parison blows out. Never.

【００１１】また、前記中空パリソン内にゴム等の弾性
材を介して加圧流体を吹き込む際、中空パリソンの外側
にゴム等の弾性材を設け、吹き込み成形用割型（キャビ
ティ）内をパリソンの内側よりやや低圧に保持して、前
記中空パリソンに内外両面から肉厚方向の加圧力を付加
したまま、前記型閉じした吹き込み成形用割型（キャビ
ティ）内を徐々に減圧しながら内面から加圧するので、
パリソンは内外両面から肉厚方向に均一に加圧された状
態で変形（膨張）するので、パリソンは肉厚を一定に保
持しながら徐々に薄くなるから成形品の肉厚を一定にコ
ントロールできる。When a pressurized fluid is blown into the hollow parison through an elastic material such as rubber, an elastic material such as rubber is provided outside the hollow parison, and the inside of the blow mold split mold (cavity) is formed by the parison. While maintaining the pressure slightly lower than the inner side, and while applying the pressing force in the thickness direction from the inner and outer surfaces to the hollow parison, the inside of the closed mold for blow molding (cavity) is pressurized from the inner surface while gradually reducing the pressure. So
Since the parison is deformed (expanded) in a state where it is uniformly pressed in the thickness direction from both the inner and outer surfaces, the parison gradually becomes thinner while keeping the thickness constant, so that the thickness of the molded article can be controlled to be constant.

【００１２】[0012]

【実施例】以下、本発明を図面に示した実施例に沿い説
明する。ます、図１を参照して本発明方法を実施する装
置の一例を説明する。１は押出ヘッドで、図示しない公
知の押し出し成形機の先端部に装着されており、前記押
し出し成形機によって混練した熱可塑性、或は、常温可
塑性のバインダと粉末のセラミックス、或は、金属との
混合物を押し出し、パリソン２を成形する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in the drawings. First, an example of an apparatus for performing the method of the present invention will be described with reference to FIG. Reference numeral 1 denotes an extrusion head, which is mounted on the tip of a known extruder (not shown), and which is formed by mixing a thermoplastic or room temperature plastic binder kneaded by the extruder with powder ceramics or metal. The mixture is extruded and parison 2 is formed.

【００１３】３は前記押し出しヘッド１の先端に設けた
口金で、ブロー口を兼用しており、ブロー口にはゴム製
薄膜、或は、ポリエチレン等の高分子薄膜等の弾性材４
が設けられている。この弾性材４は、図３に明瞭に記載
しているように口金３内に進退する吹き出し筒５に被冠
するように設けられている。そして、該吹き出し筒５の
周囲にには多数の吹き出し孔６が穿設されている。な
お、このブロー口には図示しないエアーポンプ等の流体
圧源が接続されている。７は吹き込み成形用割型で、左
右の割型７ａ，７ｂと底型７ｃとにより構成されてい
る。８は吹き込み成形用割型７の左右の割型７ａ，７ｂ
の内周面に設けた金属ポーラス、発泡石膏、或は、通気
性焼結材等の通気性ライニング材、９は前記吹き込み成
形用割型７の左右の割型７ａ，７ｂの内側に設けたゴム
製薄膜、或は、ポリエチレン等の高分子薄膜等の弾性材
で、図５に示すように、吹き込み成形用割型７を型閉じ
した時、前記パリソン２の外形と略等しい円筒部を形成
するように中央部に円弧状の溝９ａが形成されている。
１０、１０’は給・排気口で、図示しないエアーポンプ
及び真空ポンプ等の加圧・減圧源に接続されている。９
は前記吹き込み成形用割型７を型閉じした時、該割型７
内に形成されるキャビティで、成形しようとする成形品
１２の外形形状と同一に形成されている。Reference numeral 3 denotes a mouthpiece provided at the tip of the extrusion head 1, which also serves as a blow port.
Is provided. The elastic member 4 is provided so as to cover the blow-off tube 5 which advances and retreats into the base 3, as clearly shown in FIG. A number of blowout holes 6 are formed around the blowout tube 5. A fluid pressure source such as an air pump (not shown) is connected to the blow port. Reference numeral 7 denotes a blow mold split die, which includes left and right split dies 7a and 7b and a bottom die 7c. Reference numeral 8 denotes left and right split dies 7a and 7b of the blow mold split die 7.
A gas-permeable lining material, such as metal porous, foamed gypsum, or a gas-permeable sintered material, provided on the inner peripheral surface of the mold, 9 is provided inside the left and right split molds 7a, 7b of the blow mold split mold 7. As shown in FIG. 5, when the blow mold split mold 7 is closed, a cylindrical portion substantially equal to the outer shape of the parison 2 is formed by an elastic material such as a rubber thin film or a polymer thin film such as polyethylene. An arc-shaped groove 9a is formed in the center portion so as to form the groove.
Reference numerals 10 and 10 'denote supply / exhaust ports which are connected to pressurizing / depressurizing sources such as an air pump and a vacuum pump (not shown). 9
When the blow mold split mold 7 is closed, the split mold 7
A cavity formed therein has the same outer shape as the molded product 12 to be molded.

【００１４】次に、図１から図４を参照しながら本発明
方法を工程を追って説明する。図１に示すように、粉末
のセラミックス、或は、金属を熱可塑性、或は、常温可
塑性のバインダと混合したものを、押し出し成形機によ
って混練された押し出しヘッド１から押し出し、円筒状
のパリソン２を成形する。粉末のセラミックスとして
は、アルミナ系、或は、ジルコニア系等のセラミックス
が使用されるが、特に材質的な制限はない。また、粉末
金属としては、焼結合金等を使用する。一方、バインダ
としては、熱可塑性のものとしては、ポリスチレン樹
脂、エチレンー酢酸ビニール共重合体、アクリル樹脂、
低分子量ポリプロピレン樹脂、ステアリン酸及びジブテ
レフタレートの混合物、また、常温可塑性のものとして
は、ＰＶＡ、メチルセルロース、澱粉、プロピレングリ
コール、グリセリン、トリエチレンクリコール、ポリエ
チレングリコールのアルキルエーテル及び水の混合物等
を使用するが、その成分や配合比等は成形しようとする
製品の保形性、離形性等を考慮して最適なものを選択す
ればよい。Next, the method of the present invention will be described step by step with reference to FIGS. As shown in FIG. 1, a mixture of powdered ceramics or metal and a thermoplastic or room-temperature plastic binder is extruded from an extruding head 1 kneaded by an extruder to form a cylindrical parison 2. Is molded. As the powdered ceramics, alumina-based or zirconia-based ceramics are used, but there is no particular material limitation. In addition, a sintered alloy or the like is used as the powder metal. On the other hand, as the binder, thermoplastic materials include polystyrene resin, ethylene-vinyl acetate copolymer, acrylic resin,
A mixture of low molecular weight polypropylene resin, stearic acid and dibuterephthalate, and a mixture of PVA, methylcellulose, starch, propylene glycol, glycerin, triethylene crycol, alkyl ether of polyethylene glycol and water, etc. as room temperature plasticity However, the components and the mixing ratio may be selected in consideration of the shape retention and releasability of the product to be molded.

【００１５】そして、所定の長さのパリソン２が成形さ
れたら、図２に示すように、吹き込み成形用割型７を型
閉じする。次に、押し出しヘッド１に設けたブロー口か
ら吹き出し筒５をパリソン２内に侵入させてゴム製薄膜
等の弾性材４を介して前記パリソン２の内側に空気等の
圧力流体を吹き込むと共に、給・排気口１０、１０’か
ら通気性ライニング材８を介して型閉じした吹き込み成
形用割型７内（キャビティ１１内）に空気等の圧力流体
を吹き込み、パリソン２の内側と外側の圧力を略等しく
する。When the parison 2 having a predetermined length is formed, the blow mold split mold 7 is closed as shown in FIG. Next, a blow-out cylinder 5 is inserted into the parison 2 from a blow port provided in the extrusion head 1 to blow a pressurized fluid such as air into the parison 2 through an elastic material 4 such as a rubber thin film. A pressure fluid such as air is blown into the blow mold split mold 7 (inside the cavity 11) from the exhaust ports 10, 10 ′ through the air-permeable lining material 8 to reduce the pressure inside and outside the parison 2. Equal.

【００１６】図２の状態から、パリソン２内の圧力を一
定に保つように定圧の圧力流体を供給しながらキャビテ
ィ１１内を徐々に減圧していく。この時、パリソン２内
の圧力がキャビティ内の圧力よりも低くならないように
制御する。従って、図３に示すように、パリソン２には
ゴム製薄膜等の弾性材４、９を介して内外両面から肉厚
方向に均一に所定の加圧力を加えられたまま、パリソン
２の内面と外面との差圧により、徐々に膨張する。この
時、パリソン２は内外両面から全体的に均一な所定の加
圧力を加えられているため、膨張率の相違によってパリ
ソンの肉厚が不均一に成るのを修正し、均一な肉厚を保
持したまま膨張する。そして、パリソン２が吹き込み成
形用割型７の内周面（通気性ライニング材８の表面）に
接触すると、それ以上の膨張はできないため、パリソン
２はキャビティ１１の内面形状に倣った形に成形され
る。From the state shown in FIG. 2, the pressure inside the cavity 11 is gradually reduced while supplying a constant pressure fluid so as to keep the pressure inside the parison 2 constant. At this time, control is performed so that the pressure in the parison 2 does not become lower than the pressure in the cavity. Therefore, as shown in FIG. 3, the inner surface of the parison 2 is kept in contact with the inner surface of the parison 2 while a predetermined pressing force is uniformly applied to the parison 2 from both the inner and outer surfaces through the elastic members 4 and 9 such as rubber thin films. It gradually expands due to the pressure difference with the outer surface. At this time, since the parison 2 is applied with a uniform predetermined pressing force from both the inside and the outside, it is corrected that the thickness of the parison becomes non-uniform due to the difference in the expansion rate, and the uniform thickness is maintained. It swells as it is. When the parison 2 comes into contact with the inner peripheral surface of the blow mold splitting mold 7 (the surface of the gas-permeable lining material 8), the parison 2 cannot be further expanded, so that the parison 2 is formed into a shape following the inner surface shape of the cavity 11. Is done.

【００１７】そして、前記の成形が完了すると、図４に
示すように、押し出しヘッド１に設けたブロー口からの
圧力流体の吹き込みを中止し、逆に排気に切り換える。
このため、パリソン２内のゴム製薄膜等の弾性材４は収
縮しパリソン２の内面から離れ、吹き出し筒５に密着す
る程度に収縮した後、吹き出し筒５を口金３内に引き込
む。この図４に示す状態で、キャビティ１１内を減圧
（排気）状態に保ったまま、前記吹き込み成形用割型７
を型開きすると、成形品１２は前記口金３と底型７ｃに
支持された状態で離型され、前記口金３及び底型７ｃか
ら取り外せば、図７に示すような成形品１２が得られ
る。When the molding is completed, as shown in FIG. 4, the blowing of the pressurized fluid from the blow port provided in the extrusion head 1 is stopped, and the operation is switched to exhaust.
For this reason, the elastic material 4 such as a rubber thin film in the parison 2 contracts and separates from the inner surface of the parison 2, and contracts to such a degree that the elastic member 4 comes into close contact with the blowing tube 5, and then the blowing tube 5 is drawn into the base 3. In the state shown in FIG. 4, while maintaining the inside of the cavity 11 in a reduced pressure (exhaust) state, the blow mold split mold 7 is formed.
When the mold is opened, the molded product 12 is released while being supported by the base 3 and the bottom die 7c. When the molded product 12 is removed from the base 3 and the bottom die 7c, a molded product 12 as shown in FIG. 7 is obtained.

【００１８】なお、前記実施例では、パリソン２の外側
にもゴム製薄膜等の弾性材９を設け、吹き込み成形用割
型７ａ、７ｂの内周面に通気性ライニング材８を設けた
場合について例示したが、これらは必ずしも設けなくて
も良い。もし、パリソン２の外側にゴム製薄膜等の弾性
材９を設けなかった場合、パリソン２の外側は直接圧力
流体に接触することになり、パリソン２を外側から加圧
する際、加圧力の均一化という意味ではゴム製薄膜等の
弾性材９を設けるのが望ましい。In the above embodiment, the elastic member 9 such as a rubber thin film is provided on the outside of the parison 2 and the breathable lining material 8 is provided on the inner peripheral surfaces of the blow mold dies 7a and 7b. Although illustrated, these need not necessarily be provided. If the elastic material 9 such as a rubber thin film is not provided outside the parison 2, the outside of the parison 2 comes into direct contact with the pressurized fluid, and when the parison 2 is pressed from the outside, the pressing force is made uniform. In this sense, it is desirable to provide an elastic material 9 such as a rubber thin film.

【００１９】また、通気性ライニング材８を設けなかっ
た場合、給・排気口１０、１０’から直接給・排気する
ことになるので、圧力流体の圧力バランスを考慮して給
・排気口１０、１０’の位置及び数等を選定すれば良
い。更に、本実施例では、パリソン２内への圧力流体の
給・排気用のブロー口を口金３側に設けた例について説
明したが、このブロー口は底型７ｃ側に設けても良い。
なお、前記実施例では、吹き出し筒５を口金３内に進退
させるようにしたものについて例示したが、パリソン２
の成形時、或は、成形品の離形時等に吹き出し筒５が邪
魔にならない場合には、常時口金３の外に突出させてお
くようにしてもよい。If the air-permeable lining material 8 is not provided, the air is supplied and exhausted directly from the supply / exhaust ports 10 and 10 '. What is necessary is just to select the position and number of 10 '. Further, in this embodiment, an example is described in which the blow port for supplying and exhausting the pressurized fluid into the parison 2 is provided on the base 3 side, but this blow port may be provided on the bottom mold 7c side.
In the above-described embodiment, an example is described in which the blowing cylinder 5 is advanced and retracted into the base 3.
If the blow-out tube 5 does not become an obstacle during the molding of the molded article or the release of the molded product, the projecting tube 5 may always be projected outside the base 3.

【００２０】[0020]

【発明の効果】本発明によれば、粉末のセラミックス、
或は、金属の小口径・大胴径の成形品の成形を、従来の
泥奨鋳込み法や、可溶性中子を使用した射出成形法に変
わり、吹き込み成形法によって成形が可能であるから、
セラミックス成形品等を簡易に、しかも均質の製品を工
業的に量産可能となり、セラミックス成形品等の用途が
格段に広がる。According to the present invention, powdery ceramics,
Alternatively, molding of small-diameter and large-diameter molded products of metal can be changed to the conventional mud casting method or the injection molding method using a soluble core, and molding can be performed by a blow molding method.
It is possible to easily mass-produce ceramic molded products and the like and homogeneous products industrially, and the use of ceramic molded products and the like is greatly expanded.

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

【図１】本発明の一実施例を示す型開き状態の正断面図
である。FIG. 1 is a front sectional view of a mold open state showing an embodiment of the present invention.

【図２】同型閉じ状態を示す正断面図である。FIG. 2 is a front sectional view showing the same mold closed state.

【図３】同成形途中の状態を示す正断面図である。FIG. 3 is a front sectional view showing a state during the molding.

【図４】同成形完了状態を示す正断面図である。FIG. 4 is a front sectional view showing a state in which the molding is completed.

【図５】吹き込み成形用割型に装着する弾性材の一例を
示す斜視図である。FIG. 5 is a perspective view showing an example of an elastic material to be attached to a blow mold split mold.

【図６】吹き込み成形用割型の一例を示す斜視図であ
る。FIG. 6 is a perspective view showing an example of a blow mold split mold.

【図７】本発明方法により成形した成形品の一例を示す
断面図である。FIG. 7 is a cross-sectional view showing an example of a molded product molded by the method of the present invention.

【図８】従来の吹き込み成形法による成形途中の状態を
示す正断面図である。FIG. 8 is a front sectional view showing a state in the middle of molding by a conventional blow molding method.

【符号の説明】[Explanation of symbols]

１ 押し出しヘッド ２ パリソン ３ 口金 ４ 弾性材（ゴ
ム製薄膜等の） ５ 吹き出し筒 ６ 吹き出し孔 ７ 吹き込み成形用割型 ８ 通気性ライ
ニング材 ９ 弾性材（ゴム製薄膜等の） １０ 給・排気
口 １１ キャビティ １２ 成形品REFERENCE SIGNS LIST 1 extrusion head 2 parison 3 base 4 elastic material (such as rubber thin film) 5 blowing cylinder 6 blow hole 7 split mold for blow molding 8 breathable lining material 9 elastic material (such as rubber thin film) 10 supply / exhaust port 11 Cavity 12 Molded product

───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.6，ＤＢ名) B28B 1/00 B28B 7/34 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 6 , DB name) B28B 1/00 B28B 7/34

Claims (2)

(57)【特許請求の範囲】(57) [Claims] 【請求項１】 押し出し成形機によって粉末のセラミッ
クス或は金属とバインダとの混合物を混練して押し出
し、円筒状の中空パリソンを成形し、該中空パリソンを
吹き込み成形用割型に挿入した後、吹き込み成形用割型
を型閉じし、割型内を徐々に減圧しながら中空パリソン
内に加圧流体を吹き込むことを特徴とする中空成形体の
成形方法。1. A mixture of a powdered ceramic or metal and a binder is kneaded and extruded by an extrusion molding machine to form a cylindrical hollow parison, and the hollow parison is inserted into a split mold for blow molding and then blown. A method for molding a hollow molded body, comprising closing a mold for molding, and blowing a pressurized fluid into a hollow parison while gradually reducing the pressure in the mold. 【請求項２】 請求項１に記載の中空成形体の成形方法
において、型閉じした吹き込み成形用割型内を減圧する
際、前記中空パリソンの外側にゴム等の弾性材を設け、
吹き込み成形用割型内をパリソンの内側よりやや低圧に
保持して前記中空パリソンを内外両面から肉厚方向に加
圧しながら成形するようにしたことを特徴とする中空成
形体の成形方法。2. The method for molding a hollow molded article according to claim 1, wherein when the inside of the blow mold split mold is closed, an elastic material such as rubber is provided outside the hollow parison.
A method of forming a hollow molded body, wherein the inside of a blow mold is maintained at a slightly lower pressure than the inside of a parison, and the hollow parison is molded while being pressed from both the inner and outer surfaces in the thickness direction.
JP5345469A 1993-12-22 1993-12-22 Molding method of hollow molded body Expired - Lifetime JP2867864B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5345469A JP2867864B2 (en) 1993-12-22 1993-12-22 Molding method of hollow molded body

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5345469A JP2867864B2 (en) 1993-12-22 1993-12-22 Molding method of hollow molded body

Publications (2)

Publication Number Publication Date
JPH07178710A JPH07178710A (en) 1995-07-18
JP2867864B2 true JP2867864B2 (en) 1999-03-10

Family

ID=18376813

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5345469A Expired - Lifetime JP2867864B2 (en) 1993-12-22 1993-12-22 Molding method of hollow molded body

Country Status (1)

Country Link
JP (1) JP2867864B2 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2372958B (en) * 2001-03-06 2004-10-27 Ceram Res Ltd Mould assemblies
JP7054883B2 (en) * 2018-08-16 2022-04-15 英志 高橋 How to make a hollow sphere using plaster

Also Published As

Publication number Publication date
JPH07178710A (en) 1995-07-18

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