JPH0427007B2 - - Google Patents
Info
- Publication number
- JPH0427007B2 JPH0427007B2 JP62239991A JP23999187A JPH0427007B2 JP H0427007 B2 JPH0427007 B2 JP H0427007B2 JP 62239991 A JP62239991 A JP 62239991A JP 23999187 A JP23999187 A JP 23999187A JP H0427007 B2 JPH0427007 B2 JP H0427007B2
- Authority
- JP
- Japan
- Prior art keywords
- core
- molding
- molded product
- thermoplastic resin
- 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.)
- Expired - Lifetime
Links
- 238000000465 moulding Methods 0.000 claims description 62
- 238000000034 method Methods 0.000 claims description 31
- 239000000463 material Substances 0.000 claims description 26
- 229920005992 thermoplastic resin Polymers 0.000 claims description 18
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 17
- 235000011089 carbon dioxide Nutrition 0.000 claims description 13
- 239000000945 filler Substances 0.000 description 18
- 239000003365 glass fiber Substances 0.000 description 10
- 239000000835 fiber Substances 0.000 description 8
- 239000011521 glass Substances 0.000 description 7
- 229920005989 resin Polymers 0.000 description 6
- 239000011347 resin Substances 0.000 description 6
- 239000010409 thin film Substances 0.000 description 6
- 239000000155 melt Substances 0.000 description 4
- -1 polypropylene Polymers 0.000 description 4
- RNFJDJUURJAICM-UHFFFAOYSA-N 2,2,4,4,6,6-hexaphenoxy-1,3,5-triaza-2$l^{5},4$l^{5},6$l^{5}-triphosphacyclohexa-1,3,5-triene Chemical compound N=1P(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP=1(OC=1C=CC=CC=1)OC1=CC=CC=C1 RNFJDJUURJAICM-UHFFFAOYSA-N 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 239000003063 flame retardant Substances 0.000 description 3
- 239000004033 plastic Substances 0.000 description 3
- 229920003023 plastic Polymers 0.000 description 3
- 241000219122 Cucurbita Species 0.000 description 2
- 235000009852 Cucurbita pepo Nutrition 0.000 description 2
- 235000008331 Pinus X rigitaeda Nutrition 0.000 description 2
- 235000011613 Pinus brutia Nutrition 0.000 description 2
- 241000018646 Pinus brutia Species 0.000 description 2
- 239000004743 Polypropylene Substances 0.000 description 2
- 229910002092 carbon dioxide Inorganic materials 0.000 description 2
- 239000001569 carbon dioxide Substances 0.000 description 2
- 238000000748 compression moulding Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229920001155 polypropylene Polymers 0.000 description 2
- 239000012783 reinforcing fiber Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 229920000049 Carbon (fiber) Polymers 0.000 description 1
- 239000004677 Nylon Substances 0.000 description 1
- 229930182556 Polyacetal Natural products 0.000 description 1
- 239000004952 Polyamide Substances 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 239000004793 Polystyrene Substances 0.000 description 1
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 239000004917 carbon fiber Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000001934 delay Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229920006351 engineering plastic Polymers 0.000 description 1
- 239000010408 film Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229920001903 high density polyethylene Polymers 0.000 description 1
- 239000004700 high-density polyethylene Substances 0.000 description 1
- 229920001519 homopolymer Polymers 0.000 description 1
- 239000012770 industrial material Substances 0.000 description 1
- 238000001746 injection moulding Methods 0.000 description 1
- 239000011256 inorganic filler Substances 0.000 description 1
- 229910003475 inorganic filler Inorganic materials 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229920001778 nylon Polymers 0.000 description 1
- 239000002985 plastic film Substances 0.000 description 1
- 229920006255 plastic film Polymers 0.000 description 1
- 229920002647 polyamide Polymers 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 229920000139 polyethylene terephthalate Polymers 0.000 description 1
- 239000005020 polyethylene terephthalate Substances 0.000 description 1
- 229920000098 polyolefin Polymers 0.000 description 1
- 229920006324 polyoxymethylene Polymers 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 239000003507 refrigerant Substances 0.000 description 1
- 239000012779 reinforcing material Substances 0.000 description 1
- 239000005060 rubber Substances 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 238000000859 sublimation Methods 0.000 description 1
- 230000008022 sublimation Effects 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Landscapes
- Moulds For Moulding Plastics Or The Like (AREA)
- Casting Or Compression Moulding Of Plastics Or The Like (AREA)
Description
［産業上の利用分野］
本発明は、空洞状の中空部を有する成形品の成
形方法に関し、特に、成形時の熱で溶解する充填
材を所定形状に固形化してなる中子を用いて中空
部を形成するようにした中空部を有する成形品の
成形方法に関する。
［従来技術と解決すべく問題点］
プラスチツク製品、特に、工業用素材として構
造材料や機能部品に使用される、いわゆるエンプ
ラは、種々改良が進められ、今日においても各種
製品に幅広く使用されており、その用途も拡大し
ている。
しかしながら、このように材料の改良によつて
プラスチツク製品の用途は拡大しているものの、
その成形技術は、材料の進歩に比べると遅れてい
る。このため、成形技術の開発の遅れが、プラス
チツク製品の用途の拡大を妨げている一面もあ
る。
現在の成形技術では一体成形が不可能もしくは
非常に困難な成形品の一例として、空洞状の中空
部を有する成形品がある。従来、空洞を有する成
形品、例えば自動車用のバンパービーム等は、第
３図に示すように表側膨出部材２１と裏側平板部
材２２をそれぞれ、別個に成形し、その後両部材
を重ね合せて溶着成形していた。
このように、従来の成形技術によると、中空部
を有する成形品の一体成形はほとんど不可能であ
り、どうしても数工程からなる成形手段を採用せ
ざるを得なかつた。このため、成形に多くの費用
と時間を要し、これが製品のコストアツプに大き
な影響を与えるといつた問題があつた。
なお、特公昭52−18226号等において、消失可
能な中子を用いた圧縮成形方法が開示されてお
り、また特開昭62−135325号において、氷を中子
とした成形方法が開示されているが、これらはい
ずれも、成形品を成形した後に、中子溶解装置に
よつて中子を溶解し、中子を取り除くものであ
り、上述の従来技術と同様の問題を有している。
本発明の目的は、上記の問題点を除去し、氷ま
たはドライアイスからなる中子を、成形中に、成
形時の熱によつて溶解または昇華させることによ
つて、空洞状の中空部を有する一体成形品を簡単
に得られるようにした中空部を有する成形品の成
形方法を提供することにある。
［問題点の解決手段］
上記目的を達成するため本発明の中空部を有す
る成形品の成形方法は、熱可塑性樹脂材を所定の
成形温度に加熱して金型上に供給し、この熱可塑
性樹脂材の上に、所定形状に形成してなる中子を
載置し、次いで、上記中子の上部より所定の成形
温度に加熱した新たな熱可塑性樹脂材を供給して
圧縮することによつて成形品を得るとともに、こ
の成形を行なつている間に、成形時の熱によつて
上記中子を形成する氷を溶解させ、かつ、成形後
に上記中子に達する孔をあけ、この中子に達する
孔から液化した中子を抜き出して、成形品中に空
洞状の中空部を形成する方法としてある。
また、熱可塑性樹脂材を所定の成形温度に加熱
して金型上に供給し、この熱可塑性樹脂材の上
に、ドライアイスを所定形状に形成してなる中子
を載置し、次いで、上記中子の上部より所定の成
形温度に加熱した新たな熱可塑性樹脂材を供給し
て圧縮することによつて成形品を得るとともに、
この成形を行なつている間に、成形時の熱によつ
て上記中子を形成するドライアイスを昇華させ、
かつ、この成形中に上記中子に達する孔をあけ、
この中子に達する孔から昇華した中子を抜き出し
て、成形品中に空洞状の中空部を形成する方法と
してある。
以下、図面を参照しつつ本発明を詳細に説明す
る。
第１図ａ〜ｅは、本発明成形方法によつて、空
洞を有する成形品を成形する場合の手順を示す図
である。
シート状の繊維強化熱可塑性樹脂材（以下、
FRTPという）１を予備加熱し、溶融状態とし
て成形用金型１０のキヤビテイ１１上に載置す
る。溶融状態におけるFRTP１は、自重によつ
てたれ下りキヤビテイ１１の凹部に沈み込む
（第１図ａ）。
シート状のFRTPにおける強化繊維として
は、ガラス繊維、炭素繊素、炭化ケイ素繊維な
どを使用することができるが、このうち、ガラ
ス繊維を用いることが望ましい。
ガラス繊維としては、繊維径が６〜30μで、
長さが、平均繊維長10〜100mm、もしくは実質
的に連続した長繊維のものが用いられる。これ
らのガラス繊維の形態としてはチヨツプドスト
ランドマツト、スワール（渦巻き）状マツト、
ニードルパンチングマツトあるいは直線状（一
方向引き揃え）マツトなどが挙げられる。ま
た、強化繊維として、直線状および非直線状と
したガラス繊維を混合して用いることもでき
る。
ガラス長繊維の材質としては特に制限はな
く、無アルカリガラス、アルカリガラスのいず
れでもよく、Ｅガラス、Ｃガラス、Ａガラス
等、従来からガラス長繊維に用いられる各種組
成のものが用いられる。
また、ガラス繊維マツトに含浸させる熱可塑
性樹脂としては、通常、高密度ポリエチレン、
ポリプロピレン等のポリオレフイン、ポリアミ
ド、ポリカーボネート、塩化ビニール、ポリエ
チレンテレフタレート等のポリエステル、ポリ
スチレン、ナイロン、ポリアセタール等のほ
か、種々の熱可塑性樹脂を用いることができ
る。この場合、熱可塑性樹脂へのガラス繊維の
含有率は15〜60wt.％とすることが好ましい。
本発明においては、これらの樹脂に難燃化処
理を施したり難燃剤を配合しておくことによ
り、得られる樹脂板に難燃特性を付与すること
もできる。また、無機充填剤、酸化充填剤等の
添加材を配合しておくこともできる。
なお、FRTPとしては、シート状に成形した
以外のもの、例えば押出機、射出成形機等で溶
融されたものを、そのまま供給して使用するこ
とも可能である。また、成形用樹脂として強化
材の含んでいないものを用いることもできる。
次に、FRTP１の凹部に、充填材を所定形状
に固形化してなる中子２を載置する（第１図
ａ）。
中子２には、成形温度より低い温度で溶解あ
るいは昇華する氷、ドライアイス等の流動性を
有する充填材を用いる。これらの充填材は固形
化した状態において所定の形状に加工したり、
固形化する段階で所定の形状とすることによつ
て中子２を形成する。
このうち、氷は種々の形状に加工しやすいの
で、中空部を複雑な形状に成形することが可能
となる。ドライアイスも比較的複雑な形状に加
工できるが、氷およびドライアイスのいずれも
耐圧が20〜200Kg／cm2であるので、この範囲内
の圧力で成形する場合に充填材として用いる。
これらの充填材は、包まないでそのまま固形
化し中子２として使用することもできるが、プ
ラスチツクフイルムあるいは薄いゴム等の薄膜
部材で包んで中子２とすると、造形が容易にな
るとともに型崩れや充填材の飛散等を防止でき
て実用上好ましい。なお、造形時にのみ薄膜部
材を用い、FRTP１の上部に載置するときに薄
膜部材を剥がして用いることも可能である。
次に、中子２を凹部に載置したFRTP１の上
部に、加熱して溶融状態とした新たなシート状
のFRTP３を載置する（第１図ｂ）。
そして、金型１０の製品成形用のコアー１２
を下降させ、下部のFRTP１と中子２および上
部のFRTP３とを一体的に成形する（第１図
ｃ）。
この上部のFRTP３としては、下部のFRTP
１と同様のものを用いる。
この圧縮成形を行なつている間に、特に、成
形品（樹脂）を冷却している間に、成形時（樹
脂）の熱で中子を形成する氷は溶解し、またド
ライアイスは昇華する。
なお、本成形時に、中子２をなす充填材とし
てドライアイスを用いる場合は、成形中にドラ
イアイスが昇華して発生する炭酸ガスを適宜排
出しながら行なうことが好ましい。炭酸ガスの
排出は、金型１０の一部に、中子２の位置まで
貫通する小径の排気管等を設けておくなどの手
段により、容易に行なうことができる。
この場合は、中子２をなす充填材を抜き出す
ための孔を成形中に設けることができるので、
後述する成形後の孔あけ工程は不要となる。
次いで、充填材を抜き出すための小さい孔４
を成形品にあけ、この孔４から成形時の熱によ
つて溶解または昇華して液体または気体となつ
た充填材を抜き出す（第１図ｄ，ｅ）。ここで、
第１図ｅは同図ｄのＡ−Ａ線断面図である。
充填材を薄膜部材で包んで中子２として用い
る場合には、薄膜部材を貫通して孔４を形成す
る。
このようにして、成形品中から中子２をなし
た充填材を全部抜き出すと、所定の形状からな
る空洞を有する成形品を得ることができる。
上記説明においては、空洞を有する成形品の成
形方法について説明したが、本発明は、第２図に
示すような孔を有する成形品の成形にも実施でき
る。すなわち、孔５が段状になつており、内部孔
５ａの方が外部孔５ｂより径の大きい成形品の成
形に実施できる。この場合は、外部孔５ｂに相当
し金型に接する部分を有した中子２を内包して成
形した後、薄膜部材を破るなどして、中子２を形
成する充填材を外部孔５ｂに相当する部分より抜
き出すことができるので、充填材抜き出し用の孔
を設ける必要がない。
また、本発明は、通常の横孔あるいはアンダカ
ツトを有するような成形品の成形に実施できるこ
とも勿論である。
このように、本発明の成形方法によれば、複雑
な形状の中空部を有する成形品を得ることができ
るとともに、成形品を中空化することにより製品
の軽量化を図ることができる。また、充填材とし
て、氷、ドライアイス等の冷媒を用いているので
成形工程における冷却効率が高く、成形サイクル
を早めることができる。さらに、二重構造とする
ことが可能なので、成形品の強度を高めることが
できる。
［実施例］
(1) FRTP１
イ ガラス繊維
Ｅガラス
繊維長：平均50mm
繊維径：22μ
をニードルパンチしてマツト化したもの。
ロ 熱可塑性樹脂
ポリプロピレン（MI7.ホモポリマー）
ハ 配合比
ガラス繊維／熱可塑性樹脂＝40／60wt.％
ニ シート
上記イ〜ハの条件からなる厚さ3.8mmのブ
ランクに成形。
(2) 中子
ポリエチレンフイルム内に充填材として水を
入れ、ひようたん形（最大半径24mm、最小半径
15mm、長さ300mm）に氷結して固形化。
(3) 金型
底部：幅40mm、長さ500mm、深さ30mm
開口部：幅70mm、長さ500mm、深さ10mm
(4) 成形条件と手順
イ 200℃に予備加熱した上記シート（100×
600mm）を二枚金型に供給。
ロ ひようたん形に形成した氷からなる上記中
子をシート上に載置。
ハ 200℃に予備加熱した上記シート（40×600
mm）を四枚金型に供給し、金型を閉じて100
Kg／cm2の圧力でプレス。
ニ 成形品を冷却後取り出し、中子に達する
2.0mmの孔を底部にあけ、ここより溶けて水
となつた充填材を抜き出した。
(5) 結果
この結果、ひようたん形をした空洞部を有す
る成形品を、一体的な成形工程のもとで容易に
得ることができた。また、成形品にはひげ、そ
り等がなく強度も充分であつた。
［発明の効果］
以上のように本発明の成形方法によれば、中子
として氷を用いた場合には、成形時に中子を溶解
して、成形後直ちに中子を抜出すこができ、また
中子としてドライアイスを用いた場合には、成形
時に中子を昇華して抜き出すことができる。した
がつて、空洞状の中空部を有する一体成形してな
る成形品を、簡単な工程で短時間のうちに得るこ
とができる。
[Industrial Field of Application] The present invention relates to a method for molding a molded product having a hollow part, and in particular, the present invention relates to a method for molding a molded product having a hollow part, and in particular, a method of molding a molded product having a hollow part, and in particular, a method of molding a molded part having a hollow part using a core made by solidifying a filler that melts with heat during molding into a predetermined shape. The present invention relates to a method for molding a molded article having a hollow portion that forms a hollow portion. [Prior art and problems to be solved] Plastic products, especially so-called engineering plastics, which are used as industrial materials for structural materials and functional parts, have undergone various improvements and are still widely used in various products today. , and its uses are also expanding. However, although the uses of plastic products are expanding due to improvements in materials,
Its molding technology lags behind advances in materials. For this reason, delays in the development of molding technology are hindering the expansion of applications for plastic products. An example of a molded product that is impossible or extremely difficult to integrally mold using current molding techniques is a molded product that has a hollow portion. Conventionally, molded products with cavities, such as bumper beams for automobiles, have been produced by separately molding a front bulging member 21 and a back flat plate member 22 as shown in FIG. 3, and then overlapping and welding the two members. It was being molded. As described above, according to conventional molding techniques, it is almost impossible to integrally mold a molded product having a hollow portion, and a molding method consisting of several steps has to be adopted. For this reason, there was a problem in that a lot of money and time were required for molding, which greatly affected the cost increase of the product. Furthermore, in Japanese Patent Publication No. 52-18226, etc., a compression molding method using an extinguishable core is disclosed, and in Japanese Patent Application Laid-Open No. 62-135325, a molding method using ice as a core is disclosed. However, in all of these methods, after the molded article is molded, the core is melted by a core melting device and the core is removed, and they have the same problems as the above-mentioned conventional techniques. An object of the present invention is to eliminate the above-mentioned problems, and to melt or sublimate a core made of ice or dry ice during molding by heat during molding, thereby forming a hollow hollow part. It is an object of the present invention to provide a method for molding a molded product having a hollow portion, which makes it possible to easily obtain an integrally molded product having a hollow portion. [Means for solving the problem] In order to achieve the above object, the method for molding a molded article having a hollow portion of the present invention involves heating a thermoplastic resin material to a predetermined molding temperature and supplying it onto a mold, A core formed into a predetermined shape is placed on top of the resin material, and then a new thermoplastic resin material heated to a predetermined molding temperature is supplied from above the core and compressed. During this molding, the heat during molding melts the ice that forms the core, and after molding, a hole is made to reach the core. This method involves extracting the liquefied core from a hole that reaches the core to form a hollow part in the molded product. Further, a thermoplastic resin material is heated to a predetermined molding temperature and supplied onto a mold, a core made of dry ice formed into a predetermined shape is placed on top of the thermoplastic resin material, and then, A new thermoplastic resin material heated to a predetermined molding temperature is supplied from the upper part of the core and compressed to obtain a molded product,
During this molding, the dry ice that forms the core is sublimated by the heat during molding,
And, during this molding, a hole is made to reach the core,
This method involves extracting the sublimated core from a hole that reaches the core to form a hollow part in the molded product. Hereinafter, the present invention will be explained in detail with reference to the drawings. FIGS. 1a to 1e are diagrams showing the procedure for molding a molded article having a cavity by the molding method of the present invention. Sheet-shaped fiber-reinforced thermoplastic resin material (hereinafter referred to as
(referred to as FRTP) 1 is preheated and placed in a molten state on the cavity 11 of the molding die 10. The FRTP 1 in a molten state sags under its own weight and sinks into the recess of the cavity 11 (FIG. 1a). Glass fibers, carbon fibers, silicon carbide fibers, and the like can be used as reinforcing fibers in sheet-like FRTP, but among these, it is preferable to use glass fibers. As for glass fiber, the fiber diameter is 6 to 30μ,
The average length of fibers used is 10 to 100 mm, or substantially continuous long fibers. The forms of these glass fibers include chopped strand pine, swirl pine,
Examples include needle-punched mats and linear (unidirectionally aligned) mats. Furthermore, a mixture of straight and non-linear glass fibers can be used as the reinforcing fiber. The material of the glass long fibers is not particularly limited, and may be either alkali-free glass or alkali glass, and materials of various compositions conventionally used for glass long fibers, such as E glass, C glass, and A glass, can be used. In addition, the thermoplastic resin impregnated into the glass fiber mat is usually high-density polyethylene,
In addition to polyolefins such as polypropylene, polyamides, polycarbonates, vinyl chloride, polyesters such as polyethylene terephthalate, polystyrene, nylon, polyacetal, and the like, various thermoplastic resins can be used. In this case, the content of glass fiber in the thermoplastic resin is preferably 15 to 60 wt.%. In the present invention, flame retardant properties can be imparted to the resulting resin plate by subjecting these resins to flame retardant treatment or adding a flame retardant. Further, additives such as inorganic fillers and oxidized fillers can also be blended. In addition, as FRTP, it is also possible to use a material other than one formed into a sheet shape, for example, one melted in an extruder, injection molding machine, etc., and supplied as is. Moreover, a molding resin that does not contain reinforcing material can also be used. Next, a core 2 made of solidified filler material in a predetermined shape is placed in the recess of the FRTP 1 (FIG. 1a). For the core 2, a fluid filler such as ice or dry ice that melts or sublimates at a temperature lower than the molding temperature is used. These fillers can be processed into a predetermined shape in a solidified state, or
The core 2 is formed by shaping it into a predetermined shape at the stage of solidification. Among these, ice is easy to process into various shapes, so it is possible to mold the hollow portion into a complex shape. Dry ice can also be processed into relatively complex shapes, but since both ice and dry ice have a pressure resistance of 20 to 200 kg/cm 2 , they are used as a filler when molding at a pressure within this range. These fillers can be solidified as they are without being wrapped and used as the core 2, but if they are wrapped in a thin film material such as plastic film or thin rubber to make the core 2, it will be easier to mold and will not lose its shape. This is practically preferable because it can prevent the filler from scattering. Note that it is also possible to use the thin film member only during modeling and to peel off the thin film member when placing it on top of the FRTP 1. Next, a new sheet-like FRTP 3 heated and molten is placed on top of the FRTP 1 with the core 2 placed in the recess (FIG. 1b). A core 12 for molding the product of the mold 10
is lowered, and the lower FRTP 1, the core 2, and the upper FRTP 3 are integrally molded (Fig. 1c). This upper FRTP3 is the lower FRTP
Use the same one as 1. During this compression molding, especially while cooling the molded product (resin), the heat from the molding process (resin) melts the ice that forms the core, and the dry ice sublimates. . Note that when dry ice is used as a filler for the core 2 during the main molding, it is preferable to carry out the molding while appropriately discharging carbon dioxide gas generated by sublimation of the dry ice during the molding. The carbon dioxide gas can be easily discharged by providing a small diameter exhaust pipe or the like in a part of the mold 10 that penetrates to the position of the core 2. In this case, a hole for extracting the filler material forming the core 2 can be provided during molding.
The hole-drilling step after molding, which will be described later, becomes unnecessary. Next, a small hole 4 is made for extracting the filling material.
A hole 4 is made in the molded product, and the filler, which has become liquid or gas by melting or sublimating due to the heat during molding, is extracted from this hole 4 (Fig. 1 d, e). here,
FIG. 1e is a sectional view taken along the line A--A in FIG. 1d. When the filler is wrapped in a thin film member and used as the core 2, holes 4 are formed through the thin film member. In this manner, when all the filler material forming the core 2 is extracted from the molded product, a molded product having a cavity of a predetermined shape can be obtained. In the above description, a method for molding a molded article having a cavity has been described, but the present invention can also be implemented for molding a molded article having holes as shown in FIG. That is, the holes 5 are stepped, and the inner hole 5a can be used to mold a molded product having a larger diameter than the outer hole 5b. In this case, after the core 2, which has a portion that corresponds to the external hole 5b and contacts the mold, is molded, the filler material forming the core 2 is inserted into the external hole 5b by tearing the thin film member, etc. Since the filler can be extracted from the corresponding portion, there is no need to provide a hole for extracting the filler. Furthermore, it goes without saying that the present invention can be applied to the molding of molded products having ordinary horizontal holes or undercuts. As described above, according to the molding method of the present invention, it is possible to obtain a molded product having a hollow portion of a complicated shape, and by making the molded product hollow, it is possible to reduce the weight of the product. Furthermore, since a refrigerant such as ice or dry ice is used as the filler, the cooling efficiency in the molding process is high and the molding cycle can be accelerated. Furthermore, since it is possible to form a double structure, the strength of the molded product can be increased. [Example] (1) FRTP1 A Glass fiber E Glass fiber length: average 50mm fiber diameter: 22μ was needle-punched and made into a mat. (b) Thermoplastic resin polypropylene (MI7. homopolymer) (c) Mixing ratio Glass fiber/thermoplastic resin = 40/60wt.% (d) Sheet Molded into a 3.8 mm thick blank under the conditions A to C above. (2) Core Polyethylene film is filled with water as a filler to form a gourd shape (maximum radius 24mm, minimum radius
15mm long and 300mm long) and solidify. (3) Mold bottom: width 40mm, length 500mm, depth 30mm Opening: width 70mm, length 500mm, depth 10mm (4) Molding conditions and procedures a.
600mm) is supplied to the two-piece mold. (b) The core made of ice formed into a gourd shape is placed on the sheet. C. The above sheet preheated to 200℃ (40 x 600
Feed four pieces (mm) into the mold, close the mold and
Press at a pressure of Kg/ cm2 . D. Remove the molded product after cooling and reach the core.
A 2.0 mm hole was drilled at the bottom, and the filling material, which had melted into water, was extracted from the hole. (5) Results As a result, a molded product having a gourd-shaped cavity could be easily obtained using an integrated molding process. Furthermore, the molded product had no whiskers, shavings, etc., and had sufficient strength. [Effects of the Invention] As described above, according to the molding method of the present invention, when ice is used as the core, the core can be melted during molding and the core can be extracted immediately after molding. Furthermore, when dry ice is used as the core, the core can be sublimated and extracted during molding. Therefore, an integrally molded product having a hollow portion can be obtained in a short time through a simple process.
第１図ａ〜ｅは本発明の手順を示す説明図、第
２図は他の成形品の長手方向縦断面図、第３図は
従来技術の説明図を示す。
１，３：繊維強化熱可塑性樹脂（FRTP）、
２：中子、４：孔。
1A to 1E are explanatory diagrams showing the procedure of the present invention, FIG. 2 is a longitudinal cross-sectional view of another molded product, and FIG. 3 is an explanatory diagram of the prior art. 1, 3: Fiber reinforced thermoplastic resin (FRTP),
2: core, 4: hole.
Claims (1)
金型上に供給し、 この熱可塑性樹脂材の上に、所定形状に形成し
てなる中子を載置し、 次いで、上記中子の上部より所定の成形温度に
加熱した新たな熱可塑性樹脂材を供給して圧縮す
ることによつて成形品を得るとともに、 この成形を行なつている間に、成形時の熱によ
つて上記中子を形成する氷を溶解させ、 かつ、成形後に上記中子に達する孔をあけ、こ
の中子に達する孔から液化した中子を抜き出し
て、 成形品中に空洞状の中空部を形成することを特
徴とした中空部を有する成形品の成形方法。 ２ 熱可塑性樹脂材を所定の成形温度に加熱して
金型上に供給し、 この熱可塑性樹脂材の上に、ドライアイスを所
定形状に形成してなる中子を載置し、 次いで、上記中子の上部より所定の成形温度に
加熱した新たな熱可塑性樹脂材を供給して圧縮す
ることによつて成形品を得るとともに、 この成形を行なつている間に、成形時の熱によ
つて上記中子を形成するドライアイスを昇華さ
せ、 かつ、この成形中に上記中子に達する孔をあ
け、この中子に達する孔から昇華した中子を抜き
出して、 成形品中に空洞状の中空部を形成することを特
徴とした中空部を有する成形品の成形方法。[Claims] 1. A thermoplastic resin material is heated to a predetermined molding temperature and supplied onto a mold, and a core formed into a predetermined shape is placed on top of the thermoplastic resin material, Next, a new thermoplastic resin material heated to a predetermined molding temperature is supplied from the upper part of the core and compressed to obtain a molded product. The ice that forms the core is melted by heat, and after molding, a hole is made that reaches the core, and the liquefied core is extracted from the hole that reaches the core, creating a hollow shape in the molded product. A method for molding a molded product having a hollow portion, the method comprising forming a hollow portion. 2 A thermoplastic resin material is heated to a predetermined molding temperature and supplied onto a mold, a core made of dry ice formed into a predetermined shape is placed on top of the thermoplastic resin material, and then the above-mentioned A new thermoplastic resin material heated to a predetermined molding temperature is supplied from the upper part of the core and compressed to obtain a molded product. The dry ice that forms the core is sublimated, and during this molding, a hole is made that reaches the core, and the sublimated core is extracted from the hole that reaches the core, creating a hollow shape in the molded product. A method for molding a molded product having a hollow portion, the method comprising forming a hollow portion.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62239991A JPS6482910A (en) | 1987-09-26 | 1987-09-26 | Molding method of molded product having hollow part |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62239991A JPS6482910A (en) | 1987-09-26 | 1987-09-26 | Molding method of molded product having hollow part |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6482910A JPS6482910A (en) | 1989-03-28 |
| JPH0427007B2 true JPH0427007B2 (en) | 1992-05-08 |
Family
ID=17052848
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62239991A Granted JPS6482910A (en) | 1987-09-26 | 1987-09-26 | Molding method of molded product having hollow part |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6482910A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105383069A (en) * | 2015-11-29 | 2016-03-09 | 重庆渝瀚市政设施有限公司 | Glass fiber reinforced plastic handrail machining process |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19640510C1 (en) * | 1996-10-01 | 1998-04-16 | Fraunhofer Ges Forschung | Device and method for injection molding plastic parts with undercuts or cavities |
| JP4721251B2 (en) * | 2001-09-03 | 2011-07-13 | 富士重工業株式会社 | Manufacturing method of composite reinforcing plate |
| DE102006031325B4 (en) * | 2006-07-06 | 2010-07-01 | Airbus Deutschland Gmbh | Method for producing a fiber composite component for aerospace applications |
| GB0803823D0 (en) * | 2008-02-29 | 2008-04-09 | Victrex Mfg Ltd | Composite materials |
| JP5652156B2 (en) * | 2010-11-24 | 2015-01-14 | 三菱レイヨン株式会社 | Fiber reinforced plastic molding method |
| JP5765248B2 (en) * | 2012-01-16 | 2015-08-19 | トヨタ自動車株式会社 | Manufacturing method of abutting part |
| TWI616297B (en) * | 2012-06-12 | 2018-03-01 | 三菱化學股份有限公司 | Forming method of fiber reinforced plastics and forming apparatus thereof |
| WO2019222797A1 (en) * | 2018-05-21 | 2019-11-28 | The University Of Sydney | A method of fabricating a casting |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5218226A (en) * | 1975-08-01 | 1977-02-10 | Kobe Steel Ltd | Exhaust valve with pilot valves for expansion apparatus |
| JPS57105317A (en) * | 1980-10-31 | 1982-06-30 | Messerschmitt Boelkow Blohm | Manufacture of connecting element consisting of fiber composite material |
| JPS5983609A (en) * | 1982-11-04 | 1984-05-15 | Aisin Seiki Co Ltd | Preparation of molded hollow resin product |
| JPS59120344A (en) * | 1982-12-28 | 1984-07-11 | Fujikin:Kk | Method and core for casting hollow object made of metal or plastics |
| JPS6045541A (en) * | 1983-04-21 | 1985-03-12 | メルク フロスト カナダ，インコーポレーテツド | Leukotriene antagonistic substance |
| JPS62135325A (en) * | 1985-12-10 | 1987-06-18 | Kanto Yakin Kogyo Kk | Method for molding article having complicated shape |
-
1987
- 1987-09-26 JP JP62239991A patent/JPS6482910A/en active Granted
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5218226A (en) * | 1975-08-01 | 1977-02-10 | Kobe Steel Ltd | Exhaust valve with pilot valves for expansion apparatus |
| JPS57105317A (en) * | 1980-10-31 | 1982-06-30 | Messerschmitt Boelkow Blohm | Manufacture of connecting element consisting of fiber composite material |
| JPS5983609A (en) * | 1982-11-04 | 1984-05-15 | Aisin Seiki Co Ltd | Preparation of molded hollow resin product |
| JPS59120344A (en) * | 1982-12-28 | 1984-07-11 | Fujikin:Kk | Method and core for casting hollow object made of metal or plastics |
| JPS6045541A (en) * | 1983-04-21 | 1985-03-12 | メルク フロスト カナダ，インコーポレーテツド | Leukotriene antagonistic substance |
| JPS62135325A (en) * | 1985-12-10 | 1987-06-18 | Kanto Yakin Kogyo Kk | Method for molding article having complicated shape |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105383069A (en) * | 2015-11-29 | 2016-03-09 | 重庆渝瀚市政设施有限公司 | Glass fiber reinforced plastic handrail machining process |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6482910A (en) | 1989-03-28 |
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