JP3605369B2

JP3605369B2 - Molding method of propeller blade mold

Info

Publication number: JP3605369B2
Application number: JP2001089585A
Authority: JP
Inventors: 真吾錦戸; 友紀古川
Original assignee: Mitsubishi Heavy Industries Ltd
Current assignee: Mitsubishi Heavy Industries Ltd
Priority date: 2001-03-27
Filing date: 2001-03-27
Publication date: 2004-12-22
Anticipated expiration: 2021-03-27
Also published as: JP2002283002A

Description

【０００１】
【発明の属する技術分野】
本発明は、舶用プロペラ翼等の複雑な３次元形状を有する鋳型の造型方法に関する。
【０００２】
【従来の技術】
従来の舶用プロペラのプロペラ翼の鋳造用鋳型の造型方法を図２から図５に基づき説明する。図２（ａ）は舶用のプロペラとそのプロペラ翼の断面を模式的に示す説明図であり、同図（ｂ）は（ａ）中に断面で示されたプロペラ翼の鋳型の説明図である。また、図３は、プロペラ翼の鋳型の従来の造型方法の説明図であり、下型の造型工程を示し、図４は同じく上型の造型工程を示す説明図である。図５は、下型造型時の断面説明図である。
【０００３】
舶用のプロペラ１は、図２（ａ）に示すようにボス部２の周囲に一体的に複数のプロペラ翼３が鋳造で形成されている。プロペラ翼３は鋳造後、機械加工等により整形されて（以下、同整形代は省略して鋳型の造型につき説明する）、船舶に装備されるが、図１（ａ）中、矢印Ａの方向に回転することによって、船体４が図１（ａ）中、矢印Ｂの方向に推進される。
【０００４】
そのためには、プロペラ翼３は回転によって、回転方向Ａを向いた前進面３ｂから、回転方向Ａの逆を向いた後進面３ａへの推力を受けるための翼断面形状とピッチ、捩じり等を備えた３次元の複雑な形状を有している。
【０００５】
上記のような、プロペラ１を鋳造する場合、鋳物である各プロペラ翼３は、図２（ｂ）に同図（ａ）中のプロペラ翼３断面の位置の断面で示すような鋳型１０によって鋳造される。
【０００６】
そして、プロペラ翼３の鋳型１０をプロペラ１の完成時の配置に合わせ放射状に複数設け、その中央に図示しないボス部２の鋳型を設け、ボス部２の鋳型の下側からプロペラ１の溶湯を流し込み、ボス部２の鋳型とプロペラ翼３の鋳型１０とに同時に注湯して一体のプロペラ１を鋳造するのが一般的である。
【０００７】
各プロペラ翼３の鋳型１０は、図２（ｂ）に示すように、プロペラ翼３の前進面３ｂを形成する前進面形成部１３ｂを造型した下型上面１２ａを備える下型１２と、プロペラ翼３の後進面３ａを形成する後進面形成部１３ａを造型した上型１１とからなり、前進面形成部１３ｂと後進面形成部１３ａとの間にプロペラ翼３の断面をなす空洞部１３が形成されるようになっている。
【０００８】
空洞部１３は、下型上面１２ａの型砂に前進面形成部１３ｂが造型された後、前進面形成部１３ｂ上に、プロペラ翼３の断面をなすように肉泥１９が盛りつけられ、肉泥１９の上面をプロペラ翼３の後進面３ａに合わせて整形した後、上型１１の型砂が盛りつけられ、上型１１と下型１２の型砂が共に乾燥固化した後、上型１１と下型１２を一旦開き、肉泥１９を取り除いて形成される。空洞部１３には、上述のように溶湯が注湯されて、ボス部２と一体のプロペラ翼３が形成される。
【０００９】
従来は一般に、プロペラ翼３はピッチ、捩じり等を有していても、回転中心か各半径位置での各展開断面において前進面３ｂは略直線であり、よって鋳型１０の下型１２の前進面形成部１３ｂも略直線なので、下型１２は下記のような方法で造型されていた。
【００１０】
すなわち、図３に示されるように、ボス部２の中心位置に合わせて設けられた垂直支柱１４の周りに各鋳型１０の下型１２の下型素材１２’が設置される。
【００１１】
垂直支柱１４には上下摺動可能、回動可能なようにブラケット１５が設けられ、ブラケット１５には垂直支柱１４に直角な下縁を有し横方向に延びるひき板１６が取り付けられており、ひき板１６の先端側の下縁は下型１２の外周側に設置された度板１７の上縁に当接して摺動するように配設される。
【００１２】
ひき板１６を図３中矢印Ｃのように回動すると、度板１７に従い矢印Ｄのように上下摺動しつつ、ひき板１６が下型素材１２’の型砂を掻き均して、下型１２の下型上面１２ａにプロペラ翼３の前進面３ｂに合わせた前進面形成部１３ｂが造型される。
【００１３】
なお、度板１７の上縁傾きは、ボス部２中心回りのプロペラ翼３の各半径位置に従う前進面３ｂのボス部２中心軸方向の傾きに合わせてあり、各半径位置で順次対応する度板１７に交換され、望む前進面形成部１３ｂが造型される。
【００１４】
しかる後、図４に示されるように、下型１２の前進面形成部１３ｂ上に、ボス部２中心からの半径位置毎のプロペラ翼断面をあらわす翼断面木型１８を置き、適宜なピン等で仮固定される。
【００１５】
図５（ａ）に示すように、ひき板１６により造型された前進面形成部１３ｂは翼断面木型１８の下縁１８ｂと略一致するが、翼断面木型前端１８ｃ近傍は曲線で持ち上がることが多く、その場合、下型上面１２ａ上に同じ型砂で下型盛上げ部１２ｂを形成して前進面形成部１３ｂを補正造型する。
【００１６】
以上のように鋳物の下面形成部となる前進面形成部１３ｂが完成し下型の造型が行なわれると、次に前進面形成部１３ｂ上に、下型１２の型砂と材質の異なる肉泥１９を盛りつけ、その上面を各翼断面木型１８の上縁１８ａに合わせるように整形する。
【００１７】
肉泥１９は、プロペラ翼３を形作る翼部の型となり、また、プロペラ翼３が鋳込まれる空洞部１３を形成するものであり、整形された肉泥１９の上面は、上型１１に後進面形成部１３ａを造型する型となる。
【００１８】
しかる後、肉泥１９の周囲の下型上面１２ａに剥離処理を施して、肉泥１９および下型１２の上に型砂を盛りつけることによって鋳物の上面形成部となる上型１１の後進面形成部１３ａが造型される。上型１１の型砂は肉泥１９と異なる材質であるが、下型１２と同じ材質でもよい。
【００１９】
上型１１と下型１２がともに乾燥固化したら、上型１１と下型１２を一旦図４中矢印Ｅのように離し、肉泥１９と翼断面木型１８を取り除き再び上型１１と下型１２を合わせて、プロペラ翼３が鋳込まれる空洞部１３を有する鋳型１０の造型が完成する。
【００２０】
したがって肉泥１９は、剥離除去し易い材質が選ばれる。また、翼断面木型１８は上型１１を盛りつける前に除去する場合もある。
【００２１】
ちなみに、プロペラ翼３の複数の鋳型１０は同じ垂直支柱１４、ひき板１６、度板１７等を用いてボス部２中心周りに順次造型され、それらの中央にボス部２の鋳型が接続するように造型されて、プロペラ１全体の鋳型が完成し、その後上述のように一体のプロペラ１が鋳造される。
【００２２】
【発明が解決しようとする課題】
従来のプロペラ翼の鋳型の造型は上述のように行なわれていたが、近年プロペラ翼の形状は、３次元的な複雑さを増してきており、その鋳型もその多様な形態に合わせて造型する必要が生じ、上述のような従来の造型方法では造型が困難となったり、また段取り、補正造型等の作業の工数、コストが増大することとなってきた。
【００２３】
例えば、プロペラ翼３断面において、従来のように前進面３ｂが略直線をなすものに限らず、図５（ｂ）に示すように前進面３ｂが曲線をなし、下型上面１２ａに対して翼断面木型下縁１８ｂ合わせ全長にわたる下型削取り部１２ｃを削って前進面形成部１３ｂを補正造型する必要があるものがあり、最早ひき板１６による前進面形成部１３ｂの造型が適合しないものがある。
【００２４】
また度板１７を多種用いなければならない場合もあり、かかる多様な工程を経ることにより複数のプロペラ翼３の鋳型１０の造型に差異を生ずるおそれも生じた。
【００２５】
したがって、舶用プロペラの鋳造においては多様なプロペラ翼形状に容易に対応できる鋳型の造型方法が求められており、本発明はかかる要請を踏まえ、複雑な３次元形状を有する鋳造品の鋳造のための容易かつ効率的な鋳型の造型方法を提供することを課題とするものである。
【００２６】
【課題を解決するための手段】
（１）本発明は、上記の課題を解決するためになされたものであって、その第１の手段として、下型の型砂の上面に鋳物の下面形成部を造型し、同下面形成部上に同鋳物を形作る肉泥を形成し、同下型および肉泥の上に上型の型砂を盛りつけて前記鋳物の上面形成部を上型に造型し、しかる後に上記肉泥を取除く鋳型の造型方法において、前記鋳物の断面木型の下縁を所定の位置で所定の高さ位置に垂下し固定する垂直位置固定装置によって固定し、複数の前記断面木型の下縁に合わせて前記下型の型砂の上面に鋳物の前記下面形成部を造型し、且つ、前記鋳物が舶用プロペラのプロペラ翼であって、前記鋳型が同プロペラ翼の鋳型であり、前記下面形成部は同プロペラ翼の前進面形成部であり、前記上面形成部は同プロペラ翼の後進面形成部であり、前記断面木型は前記プロペラ翼の翼断面木型であることを特徴とするプロペラ翼の鋳型の造型方法を提供する。
【００２７】
上記のように構成されることにより、第１の手段のプロペラ翼の鋳型の造型方法によれば、従来方法のように各半径位置に応じて度板を交換しつつ度板に沿わせてひき板を回動させて型砂を掻き均し、さらに、断面木型の下縁の形状に沿って下型盛上げ部や下型削取り部を設ける補正造型作業等を行なうことが不要となり、プロペラ翼の鋳型の造型作業が容易かつ効率的になるほか、断面木型の下縁の位置を自由に設定できるので、多様な形状に対応した下型の造型が可能である。
【００２８】
またプロペラ翼の鋳型を複数造型する場合には垂直位置固定装置で設定される断面木型の位置に基づき容易に全て均一に造型することができ、従来例のような、度板の設置、交換、ひき板の回動、下型盛上げ部や下型削取り部の補正造型作業等の複数の作業工程に起因する鋳型のプロペラ翼の造型のバラツキを回避することができ、鋳造の効率化、のみならず精度向上が図られる。
【００２９】
以上のように、その造型方法がプロペラ翼の鋳型の造型において有効に奏することになり、従来方法ではプロペラ翼の鋳型の造型の困難と効率の低下をもたらした多様な複雑なプロペラ翼面形状に容易に対応でき、また均一な複数のプロペラ翼をボス部の周囲に一体に鋳造することができる。
【００３０】
（２）また、第２の手段として、第１の手段のプロペラ翼の鋳型の造型方法において、前記翼断面木型は前記プロペラ翼の後進面を表す上縁を備え、同上縁に合わせて前記肉泥の上面を形成することにより、前記上型の後進面形成部を造型することを特徴とするプロペラ翼の鋳型の造型方法を提供する。
【００３１】
第２の手段によれば、第１の手段の作用に加え、プロペラ翼を形作る肉泥の形成が精度良くかつ容易となり、プロペラ翼の後進面を形成する上型の後進面形成部が多様な複雑な形状であっても容易に対応できる。
【００３２】
（３）第３の手段として、第１の手段または第２の手段のプロペラ翼の鋳型の造型方法において、前記断面木型を前記垂直位置固定装置の垂下されたシリンダのシリンダロッドに固定することを特徴とするプロペラ翼の鋳型の造型方法を提供する。
【００３３】
第３の手段によれば、第１の手段または第２の手段の作用に加え、断面木型の高さ位置の設定が容易となり、多様なプロペラ翼の鋳物形状に対し一つの垂直位置固定装置でプロペラ翼の鋳型の造型を行なえる。
【００３４】
【発明の実施の形態】
図１に基づき、本発明の実施の一形態にかかるプロペラ翼の鋳型の造型方法を説明する。図１は、本実施の形態のプロペラ翼の鋳型の造型方法による、プロペラ翼の下型および上型の造型工程の説明図である。
【００３５】
図１に示すように、従来例の図３に示す垂直支柱１４と同様に、図示しないボス部の中心位置に合わせて垂直支柱２０が立設され、垂直支柱２０の周りに各鋳型１０の下型１２の下型素材１２’が設置される。
【００３６】
垂直支柱２０には上下位置、回動位置を任意に設定して固定できるようにブラケット２１が設けられ、ブラケット２１には垂直支柱２０に直角に横方向（ボス部中心から半径方向）に延びるアーム２２が取り付けられており、アーム２２には直角（ボス部周りの接線方向）に横桁２３が設けられている。
【００３７】
各横桁２３にはアーム２２の左右両側にシリンダ２４が垂直下方に向けて垂下して取り付けられ、各シリンダ２４の下方に延びるシリンダロッド２４ａの下端は、その横桁２３のボス部中心からの半径位置におけるプロペラ翼３の断面をあらわす翼断面木型１８が取り付けられている。
【００３８】
各横桁２３の２つのシリンダ２４はそれぞれ、下端に取り付けられた翼断面木型１８の下縁１８ｂが、鋳造されるプロペラ翼３のその半径位置での前進面３ｂの傾き（ピッチ）と高さ（レーキ）に合うように設定されている。
【００３９】
横桁２３とシリンダ２４と翼断面木型１８の組み合わせは、図１において２組が図示されているが、実際には鋳造されるプロペラ翼３の３次元的形状を特定するために必要な複数組が設けられ、垂直支柱２０からシリンダ２４のシリンダロッド２４ａまでが翼断面木型１８の垂直位置固定装置３０を形成し、翼断面木型１８はシリンダ２４の操作によってその傾きと高さ位置を自由に調整、設定できる。
【００４０】
複数の翼断面木型１８の傾きと高さ位置は、それぞれプロペラ設計データから各横桁２３のシリンダ２４の半径位置に基づき容易に算出することができ、かかる数値データに基づき設定されたものである。
【００４１】
以上のような本実施の形態においては、まず、所定の半径方向位置でプロペラ設計データから高さ位置が設定された各翼断面木型１８の下縁１８ｂの形状に沿って、且つ複数の翼断面木型１８の下縁１８ｂの形状が連続するように下型１２の下型上面１２ａの型砂を掻き均し、プロペラ翼３の下面形成部である所定の前進面形成部１３ｂを造型し下型１２の造型を完成する。
【００４２】
したがって、前進面形成部１３ｂの造型において、前述の従来例のように度板１７に沿わせてひき板１６を回動させて型砂を掻き均し、回動位置に応じて度板１７を交換する必要はなく、ひき板１６による下型上面１２ａの造型に加え、さらに翼断面木型１８の下縁１８ｂの形状に沿って下型盛上げ部１２ｂを設けたり、下型削取り部１２ｃを設けたりする補正造型作業を行なうことが不要となる。
【００４３】
また、プロペラ設計の数値データから各翼断面木型１８の下縁１８ｂの位置を自由に設定できるので、プロペラ翼３の多様な形状に対応した下型１２の造型が可能となる。
【００４４】
その後、造型された下型１２の前進面形成部１３ｂの上に、下型１２の型砂と材質の異なる剥離性の良い肉泥１９を盛りつけ、その上面を各翼断面木型１８の上縁１８ａに合わせるように整形する。
【００４５】
肉泥１９は、プロペラ翼３を形作る翼部の型となり、また、プロペラ翼３が鋳込まれる空洞部１３を形成するものであり、整形された肉泥１９の上面は、上型１１にプロペラ翼３の上面形成部である所定の後進面形成部１３ａを造型する型となる。
【００４６】
しかる後、上記の垂直位置固定装置３０のシリンダロッド２４ａを翼断面木型１８から外し、肉泥１９の周囲の下型上面１２ａに剥離処理を施して、肉泥１９および下型１２の上に型砂を盛りつけることによって上型１１が造型される。上型１１の型砂は肉泥１９と異なる材質であるが、下型１２と同じ材質でもよい。
【００４７】
それ以降の工程は前述の従来例と基本的には同じであり、上型１１と下型１２がともに乾燥固化したら、上型１１と下型１２を一旦離し、肉泥１９と翼断面木型１８を取り除き再び上型１１と下型１２を合わせて、プロペラ翼３が鋳込まれる空洞部１３を有する鋳型１０の造型が完成する。
【００４８】
なお、本実施の形態においても翼断面木型１８は、上型１１を盛りつける前に除去してもよい。
【００４９】
そして、複数のプロペラ翼３の鋳型１０は、図１に図示しないボス部２（図２参照）の中心位置に合わせて立設された垂直支柱２０等で構成される垂直位置固定装置３０と翼断面木型１８を用いてボス部２の中心周りに順次造型され、それらの中央にボス部２の鋳型が接続するように造型されて、プロペラ１全体の鋳型が完成し、その後一体のプロペラ１が鋳造される。
【００５０】
したがって、本実施の形態のプロペラ翼の鋳型の造型方法によれば、複数のプロペラ翼３の鋳型１０は垂直位置固定装置３０で設定される翼断面木型１８の位置に基づき容易に全て均一に造型することができ、従来方法のように、度板１７の設置、交換、ひき板１６の回動、下型盛上げ部１２ｂや下型削取り部１２ｃの補正造型作業等の複数の作業工程に起因する鋳型１０の造型のバラツキが生ずることを回避でき、プロペラ１の鋳造の効率化、のみならずプロペラ１の精度向上を図ることができる。
【００５１】
なお、本実施の形態のプロペラ翼の鋳型の造型方法は特に下型１２の造型方法に特徴があるが、本実施の形態のプロペラ翼の鋳型の造型方法の他の応用形態として、翼断面木型１８を図１中に２点鎖線で示すように下縁１８ｂのみを用いる前進面専用翼断面木型１８’として、前進面形成部１３ｂの造型のみに実施して、その後の工程は垂直位置固定装置３０を用いず従来の方法によることもできる。しかし、プロペラ翼３の後進面３ａを表す上縁１８ａを備えれば、肉泥１９の上面の整形を同時に容易に行なえ、上型の後進面形成部１３ａが多様な複雑な形状であっても容易に対応できるようになり、より好ましい。
【００５２】
また、垂直位置固定装置３０のシリンダ２４およびシリンダロッド２４ａは、翼断面木型１８の傾きと高さ位置を特定して実施する場合は、そのデータに基づく固定ロッドに代えてもよく、垂直位置固定装置３０の構成を簡素化しつつ、本発明のプロペラ翼の鋳型の造型方法を実施できる。しかし、シリンダ２４およびシリンダロッド２４ａによれば、翼断面木型１８の高さ位置の設定が容易となり、一つの垂直位置固定装置３０で多様なプロペラ翼３の鋳型１０の造型に容易に対応できるものとなり、より好ましい。
【００５４】
以上、本発明の実施の形態を説明したが、上記実施の形態に限定されるものではなく、本発明の範囲内でその具体的構成、構造に種々の変更を加えてよいことは言うまでもない。
【００５５】
【発明の効果】
（１）請求項１の発明によれば、プロペラ翼の鋳型の造型方法を、下型の型砂の上面に鋳物の下面形成部を造型し、同下面形成部上に同鋳物を形作る肉泥を形成し、同下型および肉泥の上に上型の型砂を盛りつけて前記鋳物の上面形成部を上型に造型し、しかる後に上記肉泥を取除く鋳型の造型方法において、前記鋳物の断面木型の下縁を所定の位置で所定の高さ位置に垂下し固定する垂直位置固定装置によって固定し、複数の前記断面木型の下縁に合わせて前記下型の型砂の上面に鋳物の前記下面形成部を造型するようにし、且つ、前記鋳物が舶用プロペラのプロペラ翼であって、前記鋳型が同プロペラ翼の鋳型であり、前記下面形成部は同プロペラ翼の前進面形成部であり、前記上面形成部は同プロペラ翼の後進面形成部であり、前記断面木型は前記プロペラ翼の翼断面木型であるように構成したので、プロペラ翼の鋳型の造型作業が容易かつ効率的になるほか、断面木型の下縁の位置を自由に設定でき、多様な形状に対応した下型の造型が可能となる。
【００５６】
またプロペラ翼の鋳型を複数造型する場合には垂直位置固定装置で設定される断面木型の位置に基づき容易に全て均一に造型することができ、従来方法のような複数の作業工程に起因するプロペラ翼の鋳型の造型のバラツキが生じることを回避することができ、鋳造の効率化、のみならず精度向上を図ることができる。
【００５７】
そして、従来方法ではプロペラ翼の鋳型の造型の困難と効率の低下をもたらした多様な複雑なプロペラ翼面形状に容易に対応でき、また均一な複数のプロペラ翼をボス部の周囲に一体に鋳造することができるので舶用プロペラの製造の効率化と精度の向上が図られる。
【００５８】
（２）請求項２の発明によれば、請求項１に記載のプロペラ翼の鋳型の造型方法において、前記翼断面木型は前記プロペラ翼の後進面を表す上縁を備え、同上縁に合わせて前記肉泥の上面を形成することにより、前記上型の後進面形成部を造型するように構成したので、請求項１の発明の効果に加え、プロペラ翼の後進面を形成する上型の後進面形成部が多様な複雑な形状であっても容易に対応できるようになる。
【００５９】
（３）請求項３の発明によれば、請求項１または請求項２に記載のプロペラ翼の鋳型の造型方法において、前記断面木型を前記垂直位置固定装置の垂下されたシリンダのシリンダロッドに固定するように構成したので、請求項１または請求項２の発明の効果に加え、断面木型の高さ位置の設定が容易となり、また、多様な鋳物形状に対し一つの垂直位置固定装置でプロペラ翼の鋳型の造型を行なうことができる。
【図面の簡単な説明】
【図１】本発明の実施の一形態にかかるプロペラ翼の鋳型の造型方法による、プロペラ翼の下型および上型の造型工程の説明図である。
【図２】（ａ）は舶用のプロペラとそのプロペラ翼の断面を模式的に示す説明図であり、（ｂ）は（ａ）中に断面で示されたプロペラ翼の鋳型の説明図である。
【図３】プロペラ翼の鋳型の従来の造型方法の説明図であり、下型の造型工程を示す。
【図４】プロペラ翼の鋳型の従来の造型方法の説明図であり、上型の造型工程を示す。
【図５】従来方法の下型造型時の断面説明図である。
【符号の説明】
１プロペラ
２ボス部
３プロペラ翼
４船体
１０鋳型
１１上型
１２下型
１２ａ下型上面
１２ｂ下型盛上げ部
１２ｃ下型削取り部
１２’ 下型素材
１３空洞部
１３ａ後進面形成部
１３ｂ前進面形成部
１８翼断面木型
１８ａ上縁
１８ｂ下縁
１８’ 前進面専用翼断面木型
１９肉泥
２０垂直支柱
２１ブラケット
２２アーム
２３横桁
２４シリンダ
２４ａシリンダロッド
３０垂直位置固定装置[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method of forming a mold having a complicated three-dimensional shape such as a marine propeller blade.
[0002]
[Prior art]
A conventional method of forming a casting mold for a propeller blade of a marine propeller will be described with reference to FIGS. FIG. 2A is an explanatory diagram schematically showing a cross section of a marine propeller and its propeller blades, and FIG. 2B is an explanatory diagram of a propeller blade mold shown in cross section in FIG. . FIG. 3 is an explanatory diagram of a conventional molding method of a propeller blade mold, showing a lower molding process, and FIG. 4 is an explanatory diagram showing an upper molding process. FIG. 5 is an explanatory cross-sectional view during lower molding.
[0003]
As shown in FIG. 2A, the marine propeller 1 has a plurality of propeller blades 3 integrally formed around a boss portion 2 by casting. After the casting, the propeller blades 3 are shaped by machining or the like (hereinafter, the shaping allowance is omitted, and the molding of the mold will be described). The propeller blades 3 will be mounted on a ship, but in the direction of arrow A in FIG. The hull 4 is propelled in the direction of arrow B in FIG.
[0004]
To this end, the propeller blades 3 are rotated to receive a thrust from the advancing surface 3b facing the rotation direction A to the reversing surface 3a facing the rotation direction A. And has a three-dimensional complicated shape.
[0005]
When the propeller 1 is cast as described above, each propeller blade 3 as a casting is cast by a mold 10 as shown in the cross section of the cross section of the propeller blade 3 in FIG. Is done.
[0006]
A plurality of molds 10 for the propeller blades 3 are radially provided in accordance with the arrangement at the time of completion of the propeller 1, and a mold for the boss 2 (not shown) is provided at the center thereof. In general, the casting is performed by pouring the molten metal into the mold of the boss portion 2 and the mold 10 of the propeller blade 3 at the same time to cast the integral propeller 1.
[0007]
As shown in FIG. 2B, the mold 10 of each propeller blade 3 includes a lower die 12 having a lower die upper surface 12a formed with a forward surface forming portion 13b that forms a forward surface 3b of the propeller blade 3, and a propeller blade 3 comprises an upper mold 11 formed with a reversing surface forming portion 13a forming a reversing surface 3a, and a cavity 13 forming a cross section of the propeller blade 3 is formed between the advancing surface forming portion 13b and the reversing surface forming portion 13a. It is supposed to be.
[0008]
After the advancing surface forming portion 13b is formed in the mold sand on the lower mold upper surface 12a, the hollow portion 13 is provided with meat mud 19 on the advancing surface forming portion 13b so as to form a cross section of the propeller blade 3, and the meat mud 19 is formed. After the upper surface of the upper mold 11 is shaped according to the retreating surface 3a of the propeller blade 3, the mold sand of the upper mold 11 is put thereon, and the mold sand of the upper mold 11 and the lower mold 12 are both dried and solidified. It is formed by once opening and removing the mud 19. As described above, the molten metal is poured into the hollow portion 13 to form the propeller blade 3 integrated with the boss portion 2.
[0009]
Conventionally, in general, even if the propeller blades 3 have a pitch, a twist, or the like, the advancing surface 3b is substantially straight in each development cross section at the center of rotation or at each radial position. Since the advancing surface forming portion 13b is also substantially straight, the lower mold 12 is formed by the following method.
[0010]
That is, as shown in FIG. 3, the lower mold material 12 ′ of the lower mold 12 of each mold 10 is placed around a vertical support 14 provided at the center of the boss 2.
[0011]
A bracket 15 is provided on the vertical support 14 so as to be vertically slidable and rotatable. The bracket 15 is provided with a sawboard 16 having a lower edge perpendicular to the vertical support 14 and extending in the lateral direction. The lower edge of the leading edge of the milling plate 16 is disposed so as to slide on the upper edge of the dovetail plate 17 provided on the outer peripheral side of the lower die 12.
[0012]
When the milling plate 16 is rotated as shown by the arrow C in FIG. 3, the milling plate 16 is slid up and down as shown by the arrow D in accordance with the dovetail plate 17 while the sand of the lower mold material 12 'is leveled. A forward surface forming portion 13b is formed on the lower surface 12a of the lower die 12 to match the forward surface 3b of the propeller blade 3.
[0013]
The inclination of the upper edge of the plate 17 is adjusted to the inclination of the advancing surface 3b in the central axis direction of the boss 2 according to each radial position of the propeller blade 3 around the center of the boss 2, and each time the radial position sequentially corresponds. The plate 17 is replaced with a desired one, and a desired forward surface forming portion 13b is formed.
[0014]
Thereafter, as shown in FIG. 4, a wing cross-section wooden mold 18 representing a propeller wing cross section at each radial position from the center of the boss 2 is placed on the advancing surface forming portion 13 b of the lower mold 12, and appropriate pins and the like are provided. Is temporarily fixed.
[0015]
As shown in FIG. 5A, the advancing surface forming portion 13b formed by the sawing plate 16 substantially coincides with the lower edge 18b of the wing section wooden pattern 18, but the vicinity of the wing section wooden pattern front end 18c rises in a curved line. In this case, the lower mold raised portion 12b is formed with the same mold sand on the lower mold upper surface 12a, and the advance surface forming portion 13b is subjected to correction molding.
[0016]
As described above, when the advancing surface forming portion 13b serving as the lower surface forming portion of the casting is completed and the lower mold is formed, next, on the advancing surface forming portion 13b, the meat mud 19 having a different material from the mold sand of the lower mold 12 is formed. And shape the upper surface thereof so as to match the upper edge 18a of each wing section wooden mold 18.
[0017]
The meat mud 19 forms a wing portion that forms the propeller blade 3, and forms a cavity 13 into which the propeller blade 3 is cast. The mold forms the surface forming portion 13a.
[0018]
Thereafter, the lower mold upper surface 12a around the meat mud 19 is subjected to a peeling treatment, and mold sand is laid on the meat mud 19 and the lower mold 12 to form a reversing surface forming portion of the upper mold 11 which becomes an upper surface forming portion of the casting. 13a is formed. The mold sand of the upper mold 11 is made of a different material from the meat mud 19, but may be made of the same material as the lower mold 12.
[0019]
When both the upper mold 11 and the lower mold 12 are dried and solidified, the upper mold 11 and the lower mold 12 are once separated as shown by an arrow E in FIG. 4, the meat mud 19 and the wing section wooden mold 18 are removed, and the upper mold 11 and the lower mold 12 are again formed. 12, the molding of the mold 10 having the cavity 13 into which the propeller blade 3 is cast is completed.
[0020]
Therefore, as the meat 19, a material that is easily peeled and removed is selected. In addition, the wing section wooden mold 18 may be removed before the upper mold 11 is placed.
[0021]
Incidentally, the plurality of molds 10 of the propeller blade 3 are sequentially formed around the center of the boss 2 using the same vertical support 14, the sawing plate 16, the dovetail plate 17, and the like, and the mold of the boss 2 is connected to the center thereof. Then, a mold of the entire propeller 1 is completed, and then the integral propeller 1 is cast as described above.
[0022]
[Problems to be solved by the invention]
Although the molding of the conventional propeller blade mold has been performed as described above, the shape of the propeller blade has recently increased in three-dimensional complexity, and the mold is also molded according to its various forms. The necessity arises, and the molding by the above-mentioned conventional molding method becomes difficult, and the man-hours and costs of operations such as setup and correction molding are increased.
[0023]
For example, in the cross section of the propeller blade 3, the advancing surface 3b is not limited to a substantially straight line as in the prior art, but the advancing surface 3b forms a curve as shown in FIG. In some cases, it is necessary to cut the lower die shaving portion 12c over the entire length of the lower edge 18b of the cross section of the wooden die to correct the advance surface forming portion 13b, and the molding of the advance surface forming portion 13b by the sawing plate 16 is no longer appropriate. There is.
[0024]
Further, in some cases, it is necessary to use various types of the studs 17, and through such various steps, there is a possibility that a difference occurs in the molding of the mold 10 of the plurality of propeller blades 3.
[0025]
Therefore, in the casting of marine propellers, there is a need for a method of forming a mold that can easily cope with various propeller blade shapes. In view of such a demand, the present invention has been developed for casting a casting having a complicated three-dimensional shape. It is an object to provide an easy and efficient mold forming method.
[0026]
[Means for Solving the Problems]
(1) The present invention has been made to solve the above problems, and as a first means, a lower surface forming portion of a casting is formed on an upper surface of a lower mold sand, and the lower surface forming portion is formed on the lower surface forming portion. The upper mold forming sand is formed on the lower mold and the meat mud to form an upper mold, and then the mold is removed. In the molding method, the lower edge of the cross-section wooden mold of the casting is fixed at a predetermined position by a vertical position fixing device that hangs down to a predetermined height position, and is fixed to the lower edges of the plurality of cross-section wooden molds. The lower surface forming portion of the casting is formed on the upper surface of the mold sand of the mold , and the casting is a propeller blade of a marine propeller, the mold is a mold of the same propeller blade, and the lower surface forming portion is a propeller blade of the same propeller blade. An advancing surface forming portion, wherein the upper surface forming portion forms a retreating surface of the propeller blade; , And the said cross-section wooden provides molding process of the mold of the propeller blades, which is a blade section wooden of the propeller blades.
[0027]
According to the above-described configuration, according to the first method of forming a propeller blade mold, as in the conventional method, the studs are exchanged according to each radial position, and are drawn along the studs. rotates the plate leveling scraping mold sand, further, it becomes unnecessary to correct molding operations such as providing the lower die thread forming portion and the lower mold scraping portion along the shape of the lower edge of the cross-section wooden, propeller blades In addition to the fact that the molding operation of the mold is easy and efficient, the position of the lower edge of the cross-section wooden mold can be freely set, so that the lower mold corresponding to various shapes can be molded.
[0028]
Also, when molding multiple propeller blade molds, it is possible to easily and uniformly mold all of them based on the position of the wooden cross section set by the vertical position fixing device. It is possible to avoid variations in the molding of the propeller blades of the mold caused by a plurality of operation processes such as rotation of the sawing plate, correction molding work of the lower mold raising portion and the lower mold shaving portion, and the efficiency of casting is improved. accuracy improvement not only is Ru been achieved.
[0029]
As described above, the molding method is effectively performed in molding the propeller blade mold, and in the conventional method, it is difficult to mold the propeller blade mold and to reduce the efficiency of various complicated propeller blade surface shapes. It is easy to cope with and a plurality of uniform propeller blades can be cast integrally around the boss.
[0030]
( 2 ) Further, as a second means, in the method for molding a propeller blade mold of the first means, the wing cross-section wooden mold has an upper edge representing a retreating surface of the propeller blade, and is aligned with the upper edge. A method of forming a mold for a propeller blade, characterized in that the upper surface of the mud is formed to form the retreat surface forming portion of the upper die.
[0031]
According to the second means, in addition to the function of the first means, the formation of the meat and mud forming the propeller wing becomes accurate and easy, and the upper die rearward surface forming portion for forming the rearward surface of the propeller blade is diverse. Even complicated shapes can be easily handled.
[0032]
( 3 ) As a third means, in the method of molding a propeller blade mold of the first means or the second means , fixing the cross-section wooden mold to a cylinder rod of a suspended cylinder of the vertical position fixing device. The present invention provides a method for molding a propeller blade mold characterized by the following .
[0033]
According to the third means, in addition to the action of the first means or the second means , the setting of the height position of the cross-section wooden mold becomes easy, and one vertical position fixing device for various casting shapes of the propeller blades. Can be used to mold propeller wing molds.
[0034]
BEST MODE FOR CARRYING OUT THE INVENTION
With reference to FIG. 1, a method for forming a propeller blade mold according to an embodiment of the present invention will be described. FIG. 1 is an explanatory diagram of a molding process of a lower die and an upper die of a propeller blade according to the method of molding a propeller blade mold of the present embodiment.
[0035]
As shown in FIG. 1, similarly to the vertical support 14 shown in FIG. 3 of the conventional example, a vertical support 20 is erected in accordance with the center position of a boss (not shown). A lower mold blank 12 'of the mold 12 is installed.
[0036]
A bracket 21 is provided on the vertical support 20 so that the vertical position and the rotation position can be arbitrarily set and fixed. The bracket 21 has an arm extending at right angles to the vertical support 20 in a lateral direction (radial direction from the center of the boss). The arm 22 is provided with a cross beam 23 at a right angle (a tangential direction around the boss).
[0037]
A cylinder 24 is attached to each of the cross beams 23 on both left and right sides of the arm 22 so as to hang vertically downward. A lower end of a cylinder rod 24 a extending downward of each cylinder 24 has a lower end from the center of the boss portion of the cross beam 23. A wing section wooden pattern 18 representing a section of the propeller blade 3 at a radial position is attached.
[0038]
Each of the two cylinders 24 of each cross beam 23 has a lower edge 18b of the wing cross-section die 18 attached to the lower end thereof, and the inclination (pitch) and height of the advancing surface 3b at the radial position of the propeller blade 3 to be cast. It is set to match the rake.
[0039]
FIG. 1 shows two combinations of the cross beam 23, the cylinder 24, and the wing cross-section wooden mold 18. In practice, however, there are a plurality of combinations necessary for specifying the three-dimensional shape of the propeller blade 3 to be cast. A set is provided, and the vertical column 20 to the cylinder rod 24a of the cylinder 24 form a vertical position fixing device 30 of the wing section die 18, and the wing section die 18 is tilted and raised by the operation of the cylinder 24. Can be freely adjusted and set.
[0040]
The inclination and the height position of the plurality of wing cross sections 18 can be easily calculated from the propeller design data based on the radial position of the cylinder 24 of each cross beam 23, and are set based on such numerical data. is there.
[0041]
In the present embodiment as described above, first, along the shape of the lower edge 18b of each wing section wooden mold 18 whose height position is set from the propeller design data at a predetermined radial position, The mold sand on the lower mold upper surface 12a of the lower mold 12 is raked so that the shape of the lower edge 18b of the cross section wooden mold 18 is continuous, and a predetermined forward surface forming portion 13b, which is a lower surface forming portion of the propeller blade 3, is formed. The molding of the mold 12 is completed.
[0042]
Therefore, in the molding of the advancing surface forming portion 13b, as in the above-described conventional example, the milling plate 16 is rotated along the dowel plate 17 to level the mold sand, and the dowel plate 17 is exchanged according to the turning position. It is not necessary to form the lower die upper surface 12a by the sawing plate 16, and further, the lower die raising portion 12b is provided along the shape of the lower edge 18b of the wing section wooden die 18, or the lower die shaving portion 12c is provided. It is no longer necessary to perform a correction molding operation.
[0043]
In addition, since the position of the lower edge 18b of each wing section wooden form 18 can be set freely from the numerical data of the propeller design, the lower mold 12 corresponding to various shapes of the propeller blade 3 can be formed.
[0044]
After that, on the advancing surface forming portion 13b of the formed lower mold 12, a thick sediment 19 having good releasability, which is different from the material of the sand of the lower mold 12, is put, and the upper surface thereof is an upper edge 18a of each wing section wooden mold 18. Shape to match.
[0045]
The meat mud 19 forms a wing portion forming the propeller blades 3, and forms a cavity 13 into which the propeller blades 3 are cast. A predetermined reverse surface forming portion 13a which is an upper surface forming portion of the wing 3 is formed into a mold.
[0046]
Thereafter, the cylinder rod 24a of the vertical position fixing device 30 is detached from the wing section wooden mold 18, and the lower mold upper surface 12a around the meat mud 19 is subjected to a peeling treatment. The upper mold 11 is formed by providing the mold sand. The mold sand of the upper mold 11 is made of a different material from the meat mud 19, but may be made of the same material as the lower mold 12.
[0047]
The subsequent steps are basically the same as those of the above-described conventional example. When both the upper mold 11 and the lower mold 12 are dried and solidified, the upper mold 11 and the lower mold 12 are once separated, and the meat mud 19 and the wing section wooden mold are formed. The upper mold 11 and the lower mold 12 are removed again, and the molding of the mold 10 having the cavity 13 into which the propeller blade 3 is cast is completed.
[0048]
Note that, also in the present embodiment, the wing cross-section wooden mold 18 may be removed before the upper mold 11 is mounted.
[0049]
Then, the mold 10 of the plurality of propeller blades 3 includes a vertical position fixing device 30 including a vertical column 20 or the like that is erected in accordance with the center position of a boss 2 (see FIG. 2) not shown in FIG. The molds of the boss 2 are sequentially formed around the center of the boss 2 by using the wooden cross section 18, and the mold of the boss 2 is connected to the center of the boss 2. The mold of the entire propeller 1 is completed. Is cast.
[0050]
Therefore, according to the molding method of the propeller blade mold of the present embodiment, all of the molds 10 of the plurality of propeller blades 3 can be easily and uniformly based on the position of the wing section wooden mold 18 set by the vertical position fixing device 30. It can be molded, and can be formed into a plurality of work steps such as installation and replacement of the base plate 17, rotation of the sawing plate 16, and correction molding work of the lower die raising portion 12 b and the lower die shaving portion 12 c as in the conventional method. Variations in the molding of the mold 10 due to this can be avoided, and the efficiency of casting the propeller 1 as well as the accuracy of the propeller 1 can be improved.
[0051]
The method of molding a propeller blade mold according to the present embodiment is particularly characterized by the method of molding the lower mold 12. However, as another application of the method of molding a propeller blade mold according to the present embodiment, As shown by a two-dot chain line in FIG. 1, the mold 18 is a wing-section wooden mold 18 ′ using only the lower edge 18b, and is used only for molding of the advancement surface forming portion 13b. A conventional method can be used without using the fixing device 30. However, if the upper edge 18a representing the retreating surface 3a of the propeller blade 3 is provided, the upper surface of the meat mud 19 can be easily and simultaneously formed, and even if the retreating surface forming portion 13a of the upper die has various complicated shapes. It is easier to respond, which is more preferable.
[0052]
In the case where the cylinder 24 and the cylinder rod 24a of the vertical position fixing device 30 are implemented by specifying the inclination and the height position of the wing section wooden form 18, the fixing rod based on the data may be used instead. The method for molding a propeller blade mold of the present invention can be performed while simplifying the configuration of the fixing device 30. However, according to the cylinder 24 and the cylinder rod 24a, it is easy to set the height position of the wing cross-section wooden mold 18, and one vertical position fixing device 30 can easily cope with the molding of the mold 10 of various propeller blades 3. And is more preferable.
[0054]
Although the embodiment of the present invention has been described above, it is needless to say that the present invention is not limited to the above-described embodiment, and various modifications may be made to the specific configuration and structure within the scope of the present invention.
[0055]
【The invention's effect】
(1) According to the first aspect of the present invention, a method of molding a propeller blade mold includes molding a lower surface forming portion of a casting on an upper surface of a lower mold sand, and forming a meat and mud forming the same casting on the lower surface forming portion. Forming, forming the upper surface forming portion of the casting into the upper mold by placing the upper mold sand on the lower mold and the meat mud, and then removing the meat mud, The lower edge of the wooden mold is fixed at a predetermined position by a vertical position fixing device hanging down and fixed at a predetermined height position, and a casting is formed on the upper surface of the lower mold sand according to the lower edges of the plurality of cross-sectional wooden molds. The lower surface forming portion is shaped , and the casting is a propeller blade of a marine propeller, the mold is a mold of the propeller blade, and the lower surface forming portion is a forward surface forming portion of the propeller blade. The upper surface forming portion is a reverse surface forming portion of the propeller blade, and Since wooden was configured such that the blade section wooden of the propeller blade, in addition to molding work of the mold of the propeller blades can be easily and efficiently, can freely set the position of the lower edge of the cross-section wooden, variety It is possible to form a lower die corresponding to various shapes.
[0056]
In addition, when molding a plurality of propeller blade molds, it is possible to easily and uniformly mold all of the molds based on the position of the cross-section wooden mold set by the vertical position fixing device, which is caused by a plurality of operation steps like the conventional method. Variations in the molding of the propeller blade mold can be avoided, and not only can the casting efficiency be improved, but also the accuracy can be improved.
[0057]
And the conventional method can easily cope with various complicated propeller blade surface shapes that caused difficulty in molding the propeller blade mold and reduced efficiency, and also cast a plurality of uniform propeller blades integrally around the boss. As a result, the efficiency and accuracy of marine propeller production can be improved.
[0058]
( 2 ) According to the invention of claim 2, in the method of molding a propeller blade mold according to claim 1 , the wing cross-section die includes an upper edge representing a retreating surface of the propeller blade, and is aligned with the upper edge. By forming the upper surface of the meat mud, the reverse surface forming portion of the upper die is formed by molding. Therefore, in addition to the effect of the invention of claim 1 , the upper die forming the reverse surface of the propeller blade is formed. Even if the reverse surface forming portion has various complicated shapes, it can be easily handled.
[0059]
(3) According to the invention of claim 3, in molding process of the mold of the propeller blade according to claim 1 or claim 2, the cross-section wooden cylinder rod suspended by a cylinder of the vertical position fixing device Since it is configured to be fixed, in addition to the effects of the invention of claim 1 or claim 2 , it is easy to set the height position of the wooden cross section, and one vertical position fixing device can be used for various casting shapes. The molding of the propeller blade mold can be performed.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a molding process of a lower mold and an upper mold of a propeller blade according to a method of molding a propeller blade mold according to an embodiment of the present invention.
FIG. 2A is an explanatory view schematically showing a cross section of a marine propeller and its propeller blade, and FIG. 2B is an explanatory view of a propeller mold shown in cross section in FIG. 2A. .
FIG. 3 is an explanatory view of a conventional molding method of a mold for a propeller blade, showing a molding step of a lower mold.
FIG. 4 is an explanatory view of a conventional molding method of a mold for a propeller blade, and shows an upper molding step.
FIG. 5 is an explanatory cross-sectional view of a conventional method at the time of lower die molding.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Propeller 2 Boss part 3 Propeller wing 4 Hull 10 Mold 11 Upper mold 12 Lower mold 12a Lower mold upper surface 12b Lower mold raising part 12c Lower mold shaving part 12 'Lower mold material 13 Hollow part 13a Reversing surface forming part 13b Advance surface forming Part 18 Wing cross section wooden mold 18a Upper edge 18b Lower edge 18 'Forward plane exclusive wing cross section wooden mold 19 Meat and mud 20 Vertical support 21 Bracket 22 Arm 23 Cross beam 24 Cylinder 24a Cylinder rod 30 Vertical position fixing device

Claims

Forming a lower surface forming portion of the casting on the upper surface of the lower mold sand, forming a meat mud forming the same casting on the lower surface forming portion, placing the upper mold sand on the lower mold and the meat mud, and forming the casting. The upper surface forming portion is formed into an upper mold, and then, in the method of forming a mold for removing the meat and mud, the lower edge of the cross-section wooden mold of the casting is vertically suspended at a predetermined position at a predetermined height and fixed. The lower surface forming part of the casting is fixed on the upper surface of the lower mold sand according to the lower edges of the plurality of cross-section wooden molds fixed by a position fixing device , and the casting is a propeller blade of a marine propeller. Wherein the mold is a mold of the propeller blade, the lower surface forming portion is a forward surface forming portion of the propeller blade, the upper surface forming portion is a backward moving surface forming portion of the propeller blade, and the cross-section wooden mold is cast propeller vane, which is a blade section wooden propeller vane The method of molding.

The molding method of a propeller blade mold according to claim 1, wherein the wing cross-section mold includes an upper edge representing a retreating surface of the propeller blade, and by forming an upper surface of the meat mud in accordance with the upper edge, A method for molding a propeller blade mold, characterized by molding the reverse surface forming portion of the upper mold.

The molding method of the template of the propeller blade according to claim 1 or claim 2, the mold of the propeller blades, characterized in that for securing the section wooden cylinder rod suspended by a cylinder of the vertical position fixing device molding how.