JP3618630B2

JP3618630B2 - Multi-head pulse current sintering system

Info

Publication number: JP3618630B2
Application number: JP2000080300A
Authority: JP
Inventors: 正雄鴇田
Original assignee: 住友石炭鉱業株式会社
Priority date: 2000-03-22
Filing date: 2000-03-22
Publication date: 2005-02-09
Anticipated expiration: 2020-03-22
Also published as: JP2001262202A

Description

【０００１】
【発明の属する技術分野】
本発明は、マルチヘッドパルス通電焼結システム（ここで、マルチヘッドとは複数の焼結を行う部分、この実施例では焼結機を備えていることを言う。）に関し、更に詳細には、１台の電源装置から複数のパルス通電焼結機に焼結のためのパルス電流を順次供給することによって通電焼結を効率良く行なうようにしたマルチヘッドパルス通電焼結システムに関する。
【０００２】
従来の通電焼結は焼結時間が長く、焼結装置への焼結型の供給作業に必要な時間が焼結時間に比較してかなり少なくて済んでいた。このため１台の供給装置に対して１台の電源装置を設けておく必要があった。
【０００３】
ところで、近年通電焼結にも改良が加えられ、例えば本出願人により提案された放電プラズマ焼結、放電焼結或いはプラズマ活性化焼結を含む、パルス電流を利用して焼結を行うパルス通電加圧焼結により焼結時間を大幅に短縮する事が可能になってきた。このため、１回の焼結に必要な時間すなわち焼結時間が、焼結型への粉体の充填、焼結装置内への焼結型の供給或いはそこからの焼結型の取り出し、更には焼結型からの焼結品の抜き取り等の付属の準備作業に必要な作業時間に比較して従来よりも極めて少なくて済むようになってきた。そこで従来の通電焼結のように１台の焼結機に対して１台の電源装置を設ける必要は必ずしも必要なくなり、１台の電源装置で複数の焼結機を動作させることにより焼結作業の効率を向上させることが期待できるようになってきた。
【０００４】
一方、パルス通電焼結では焼結に必要な電力は、低電圧（通常１００Ｖ以下）で大電流（例えば、５０００Ａ或いはそれ以上）が必要である。このため電源装置も従来の通電焼結に使用される電源装置とは異なるもので高価な装置になる。そこで、少ない電源装置で複数の焼結機を作動できれば焼結設備の簡素化、スペースの節約、更には焼結コストを低減する上でも好ましい。
【０００５】
【発明が解決しようとする課題】
本発明が解決しようとする課題は、１台の電源装置で複数の焼結機を作動できるようにしたマルチヘッドパルス通電焼結システムを提供することである。
本発明が解決しようとする他の課題は、特殊の電源切換え装置を備えていてそれによって低電圧、大電流を必要とする複数のパルス通電焼結機を１台の電源装置で作動できるようにしたマルチヘッドパルス通電焼結システムを提供することである。
【０００６】
【課題を解決するための手段】
本願発明によるマルチヘッドパルス通電焼結システムは、電源装置と、
一つの電源装置に電気的に接続可能になっていてその電源装置から焼結用のパルス電流を受けてパルス通電焼結を行なう複数のパルス通電焼結機と、
該電源装置と該複数のパルス通電焼結機とに電気的に接続されてい、該電源装置からのパルス電流を該複数のパルス通電焼結機の一つに選択的に供給する通電切換え装置とを備え、
該通電切換え装置が、電源装置に接続された平坦な通電面を有する第１及び第２の入力側端子板と、該パルス通電焼結機に接続されていて該第１の入力側端子板に隣接して配置された平坦な通電面を有する複数の第１の出力側端子板と、該パルス通電焼結機に接続されていて該第２の入力側端子板に隣接して配置された平坦な通電面を有する複数の第２の出力側端子板と、該第１の入力側及び出力側端子板に隣接してそれらと接触可能に配置されていて該第１の入力側及び出力側端子板の通電面と面接触する平坦な通電面を有する複数の第１の連通部材と、該第２の入力側及び出力側端子板に隣接してそれらと接触可能に配置されていて該第２の入力側及び出力側端子板の通電面と面接触する平坦な通電面を有する複数の第２の連通部材と、を備えて構成されている。
【０００７】
上記通電焼結システムにおいて、パルス通電焼結機に近接する位置まで被焼結材が充填された焼結型を供給する供給コンベアと、供給コンベアにより供給された焼結型をパルス通電焼結機に装填する装填装置とを備えていてもよい。更に、粉体を焼結型内に充填する自動粉体充填装置を備えていてもよい。また電源装置が低電圧で大電流の直流パルス電流を供給するものでもよい。更に、通電切換え装置が、第１及び第２の複数の連通部材毎に別個に設けられたアクチュエータを備え、第１の連通部材の任意の一つとその第１の連通部材と関連する第２の連通部材が別個に設けられたアクチュエータによって第１及び第２の入力側及び出力側端子板に押圧されるようになっていてもよい。更にまた、入力側端子板、出力側端子板及び連通部材の通電面がほぼ水平になっていて、各アクチュエータがそれぞれの連通部材の上方に配置された流体シリンダから成り、連通部材がシリンダのピストンロッドに絶縁体を介して取り付けられていてもよい。
【０００８】
本発明によるパルス通電焼結機用の通電切換え装置は、電源装置に接続された平坦な通電面を有する第１及び第２の入力側端子板と、該パルス通電焼結機に接続されていて該第１の入力側端子板に隣接して配置された平坦な通電面を有する複数の第１の出力側端子板と、該パルス通電焼結機に接続されていて該第２の入力側端子板に隣接して配置された平坦な通電面を有する複数の第２の出力側端子板と、該第１の入力側及び出力側端子板に隣接してそれらと接触可能に配置されていて該第１の入力側及び出力側端子板の通電面と面接触する平坦な通電面を有する複数の第１の連通部材と、該第２の入力側及び出力側端子板に隣接してそれらと接触可能に配置されていて該第２の入力側及び出力側端子板の通電面と面接触する平坦な通電面を有する複数の第２の連通部材と、第１及び第２の複数の連通部材毎に別個に設けられていてその連通部材を入力側及び出力側端子板に向かって移動させるアクチュエータとを備えて構成されている。
【０００９】
上記通電切換え装置において、該第１及び第２の出力側端子板と該パルス通電焼結機の可動電極とを電気的に接続する通電装置を備え、該通電装置が該可動電極に電気的に接続されかつ該可動電極と共に移動する可動電極側の接続端子と、該可動電極側接続端子と該第１又は第２の出力側端子板とを電気的に接続するフレキシブル導電体とを備えていてもよい。また、該通電装置が、該可動電極側の接続端子と該フレキシブル導電体とを電気的に接続するコネクタを該可動電極の上下動作に応答して上下動させるアクチュエータを備えていてもよい。
【実施例】
【００１０】
以下、図面を参照して本発明の実施例について説明する。
図１において、本発明によるマルチヘッドパルス通電焼結システムの一実施例が概略的に示されている。この実施例のマルチヘッドパルス通電焼結システム（以下単に通電焼結システムと呼ぶ）１は、第１及び第２の２台のパルス通電焼結機（以下単に通電焼結機と呼ぶ）２（２ａ、２ｂ）と、通電焼結機２にパルス電流を供給する電源装置３と、電源装置３に電気的に接続されていてその電源装置からのパルス電流を２台の通電焼結機２のいずれかに選択的に供給する通電切換え装置４と、通電焼結機２の近くの供給位置に粉末材料が充填済みの焼結型を供給する焼結型供給コンベア６と、供給位置に供給された焼結型を通電焼結機に装填する装填装置７と、焼結済みの焼結型を搬送する排出コンベア８と、粉体を焼結型内に充填する自動粉体充填装置９とを備え、それらは図１に示される位置関係で配置されている。
【００１１】
図３及び図４において、この実施例の通電焼結機２（２ａ、２ｂ）は、台２１１、その台に直立状態で互いに隔てて固定された複数（この実施例では２本）の支柱２１２及び支柱２１２の上端に固定された上支持板２１３を有する本体フレーム２１と、支柱２１２に上下移動可能に支持された下ハウジング組立体２２と、支柱２１２に上下移動可能に支持された上ハウジング組立体２３と、下ハウジング組立体２２に取り付けられた下通電電極組立体２４と、上支持板２１３に取り付けられているを備えている上通電電極組立体２５と、台２１１の中央に取り付けられていて下可動ハウジング組立体を上下動させる駆動装置２６とを備えている。下ハウジング組立体２２は、軸受け２２２を介して支柱２１２に滑動可能に案内支持された円板状（この実施例で）の下可動体２２１と、下可動体２２１に取り付けられた下ハウジング２２３とを有している。ハウジング２２３は底壁を形成していて下可動体２２１に取り付ける底板２２４と、底板２２４に溶接等により接続された、環状（この実施例では円環状）の側壁を構成する環状体２２５と、環状板の上端に固定されたリング部材２２６とを有している。上ハウジング組立体２３は、軸受け２３２を介して支柱２１２に滑動可能に案内支持されたリング状の上可動体２３１と、上可動体２３１に取り付けられた上ハウジング２３３とを備えている。上ハウジングは、上壁を構成する天板２３４と、環状（この実施例では円環状）の側壁を構成する環状体２３５と、環状板の下端及び上可動体に固定され、それによって上ハウジングを上可動体に取り付けているリング部材２３６とを有している。上、下ハウジング２３３及び２２３は互いに協同して焼結チャンバを画成するようになっている。上、下ハウジングは、環状体２３５、２２５をそれぞれ二重に設けることによって二重壁構造（ウオータージャケット状）にされ、中に冷却水を通す構造になっている。この焼結チャンバは図示しない装置により、例えば真空雰囲気或いは不活性ガス雰囲気等の焼結雰囲気に制御されるようになっている。なお、リング部材２２６の上面及びリング部材２３６の下面の少なくとも一方にはシールリングが設けられ、それらの面間の気密性を確保するようになっている。なお、図示しないが上ハウジングの環状体２３５には外部から焼結チャンバ内を見れるように覗き窓を設けてもよい。また、図示しないが、通電時の焼結型からの発熱からハウジングの内壁を保護するために、チャンバ内部に単層又は複数の層の環状のステンレス鋼薄板を遮熱板として設けてもよい。
【００１２】
下通電電極組立体２４は、下可動体２２１及び下ハウジングの底板２２４の中央部に形成された上下方向の貫通穴内に、絶縁ブッシュ２４６及び絶縁板２４７を介して下可動体２２１及び底板２２４に電気的に絶縁させた状態で固定された下通電電極２４１を備えている。下通電電極２４１は、この実施例では、下端にフランジ部２４３を有する円柱状の電極本体２４２と、その電極本体２４２の上端に取り付けられた電極ヘッド２４４とを有している。下通電電極２４１の内部には図示しないが外部の冷却液供給源と接続されていて中に冷却液を流す冷却通路が形成されている。下通電電極２４１は、図４［Ａ］に示されるように、フランジ部２４３を固定ボルト２４８で下可動体２２１に取り付けることによって、下可動体に固定されている。この場合、公知の絶縁スリーブ及び絶縁ワッシャ等を用いて、固定ボルト２４８の周囲での下通電電極２４１と下可動体２２１との間の電気的絶縁を確保してある。上通電電極組立体２５は、上支持板２１３の中央部に形成された上下方向の貫通穴内に、絶縁ブッシュ２５６及び２５７を介して上支持板２１３に電気的に絶縁させた状態で固定された上通電電極２５１を備えている。上通電電極２５１は、この実施例では、上端にフランジ部２４３が固定された円柱状の長い電極本体２５２と、その電極本体２５２の下端に取り付けられた電極ヘッド２５３とを有している。下通電電極２５１の内部には図示しないが外部の冷却液供給源と接続されていて中に冷却液を流す冷却通路が形成されている。上通電電極２５１は、図示しないが、フランジ部２５３を固定ボルトで上支持板２１３に取り付けることによって、上支持板に固定されている。この場合、公知の絶縁スリーブ及び絶縁ワッシャ等を用いて、固定ボルトの周囲での上通電電極２５１と上支持板２１３との間の電気的絶縁を確保してある。上通電電極２５１は上ハウジング２３３の天板２３４を上下に貫通する穴を通して伸び、下端が焼結チャンバ内に配置されるようになっている。天板２３４には絶縁ブッシュ２３８及びシール部材２３９が取り付けられている。下通電電極２４１の軸心と上通電電極２５１の軸心とは同軸になるように位置決めされている。
【００１３】
駆動装置２６は、この実施例では流体圧シリンダ２６１で構成され、そのピストンロッド２６２の先端（図で上端）には下通電電極に固定するための接続ブロック２６３が固定されている。接続ブロック２６３とピストンロッド２６２との接続方法は、ピストンロッド先端に形成された雄ねじを接続ブロックに形成された雌ねじに螺合することによって行われる。接続ブロック２６３と下通電電極２４１のと間には、後述する銅板等の導電性材料でできた接続端子４８ａと、絶縁板２６４とが接続端子を下通電電極に接触させた状態で、配置されている。接続ブロック２６３は、図４［Ａ］に示されるように、その接続ブロック２６３を固定ボルト２６６で下通電電極２４１のフランジ部２４３に取り付けることによって、下通電電極に固定されている。この場合、公知の絶縁スリーブ及び絶縁ワッシャ等を用いて、固定ボルト２６６の周囲での接続ブロック２６３と下通電電極２４１ととの間の電気的絶縁を確保してある。下ハウジング組立体２２はこのようにして下通電電極組立体２４と共に駆動装置２６により上下動される。なお、上記実施例では駆動装置として流体圧シリンダを採用したが、これに代えて電動モータで駆動する方式を採用してもよい。上通電電極２５１のフランジ部２５３と絶縁ブッシュ２５７との間には後述する銅板等の導電性材料でできた接続端子５８が配置されている。上ハウジング組立体２３を上下移動させる機構は、図４［Ｂ］に示されるように、上端が上支持板２１３に固定され下端が上可動体２３１に固定されたアクチュエータ２７で構成される。このアクチュエータ２７はこの実施例では流体シリンダ２７１で構成され、この流体シリンダのシリンダ本体の上端が上支持板２１３に固定され、ピストンロッド２７２の下端が上可動体２３１に固定されている。アクチュエータは、その軸心が、一対の支柱２１２の軸心及び上下通電電極２５１、２４１の軸心を含む面に関して所定の角度、例えば３０度或いは４５度を成す平面内に存在するように、位置決めされている。
【００１４】
上記パルス通電焼結機において、上、下ハウジング組立体２３、２２がそれぞれ上位置及び下位置になっていて、下通電電極２４１が上通電電極２５から最も離れた状態になっているとき、下通電電極２４１のヘッド２４４上には、中に被焼結材料である粉末材料ｊが充填された焼結型ａが載せられる。このとき下通電電極２４１のヘッド２４４の上面は焼結型の穴内に挿入されてセットされている下プレスコアｂの下面と接触しそれと通電できると共に所望の圧力を加え得るようになっている。焼結型が下通電電極２４１の上に位置決めされると、駆動装置２６が動作して下通電電極組立体２４及びその上の焼結型ａを、下ハウジング組立体２２と共に、焼結型の穴内に挿入された上プレスコアｃが上通電電極２５１のヘッド２５４の下面に当たるまで上昇させる。それと同時又はその後アクチュエータ２７が動作して上ハウジング組立体２３を降下させる。すると上ハウジング２３３のリング部材２３６と下ハウジング２２３のリング部材２２６とが当接して上、下ハウジングによって画成されるチャンバを外気と遮断し、そのチャンバ内を公知の方法で真空雰囲気又は不活性ガス雰囲気にする。その後駆動装置２６で下通電電極２４１を上通電電極２５１に向かって所望の圧力で押圧しながら通電電極を介して所望の電圧で所望の値の直流パルス電流を流してパルス通電焼結を行う。なお、上記実施例では上ハウジング組立体２３を上下動するアクチュエータ２７を流体シリンダで構成したが、図４［Ｃ］に示されるようにねじ軸及びそれと螺合するナットから成るねじ軸及びナット機構２７１ａで構成してもよい。このねじ軸及びナット機構２７１ａは、下可動体２２１に直立状態で回転可能に支持されていてほぼ全長に亘って雄ねじが形成されたねじ軸２７２ａと、このねじ軸２７２ａの雄ねじと螺合する雌ねじが形成されたナット２７３ａと、このねじ軸２７２ａを回転する駆動モータ２７４ａとを備えている。
【００１５】
電源装置３は、低電圧（例えば１００Ｖ以下）で大電流（例えば５０００Ａ或いはそれ以上）の直流パルス電流を供給できるものが好ましい。これは放電プラズマ焼結、放電焼結或いはプラズマ活性化焼結のようなパルス通電焼結を行う場合には低電圧で大電流の直流パルス電流が必要と成るからである。なおこのような直流パルス発生電源装置の構造自体は公知のものでよいのでその詳細な説明は省略する。
【００１６】
図５ないし図８において、本実施例の通電切換え装置４が示されている。この実施例の通電切換え装置４は１台の電源装置で２台の通電焼結機にパルス電流を供給するように構成されている。この通電切換え装置４は、本体フレーム４１の台板４１１の上に絶縁体４１２を介して台板に電気的に絶縁して固定された第１及び第２の入力側端子板４２及び４３を備えている。台板４１１の上面、したがって絶縁体４１２の上面はほぼ水平面になるように調整されていてしたがって入力端子板４２及び４３の上側の接触面すなわち通電面４２１及び４３１もほぼ水平で平坦な面に形成されている。これら入力側端子板は銅等の導電性のよい材料でしかも通電面として広い面積がとれるような幅広の板を２枚重ねにして（大きな通電容量を確保するため）構成されている。第１及び第２の入力端子板４２及び４３は同様に幅広で板状の導電板４２２及び４３２を介して電源装置にそれぞれ接続されている。これらの導電板も銅等の導電性の良い材料でつくられている。
【００１７】
台板４１１上の絶縁体４１２の上には、第１の入力側端子板４２の両側（図５で左右両側）に、その入力側端子板と隔てて（電気的に絶縁して）一対の第１の出力側端子板４４（４４ａ、４４ｂ）が固定され、第２の入力側端子板４３の両側（図５で左右両側）に、その入力側端子板と隔てて（電気的に絶縁して）一対の第２の出力側端子板（４５ａ、４５ｂ）４５が固定されている。出力側端子板４４及び４５の上側の接触面すなわち通電面４４１及び４５１もほぼ水平で平坦な面に、しかも入力側端子板の通電面と面一になるように形成されている。これら出力側端子板は銅等の導電性の良い材料でしかも通電面として広い面積がとれるような幅広の板を２枚重ねにして構成されている。第１の対の出力側端子板の一方４４ａは、同様に幅広で板状の複数の導電板４４２ａ、４４３ａを介して、第１の通電焼結機２ａの上通電電極に電気的に接続するための接続端子４６ａに接続されている。他方の第１の出力側端子板４４ｂは、同様に幅広で板状の複数の導電板４４２ｂ、４４３ｂを介して、第２の通電焼結機２ｂの上通電電極に電気的に接続するための電極端子４６ｂに接続されている。導電板４４２ａ、４４２ｂ、４４３ａ、４４３ｂも銅等の導電性のよい板材を複数枚重ねて構成されている。第２の対の出力端子板の一方４５ａは、同様に幅広で板状の複数の導電板４５２ａを介して一方（第１の通電焼結機２ａ側）の通電機構４７ａに電気的に接続されている。他方の第２の出力端子板４５ｂは、同様に幅広で板状の複数の導電板４５２ｂを介して他方（第１の通電焼結機２ｂ側）の通電機構（図示せず）に電気的に接続されている。なお、二つの通電機構は構造及び動作が全く同じであるから以下では一方４７ａについてのみ説明する。
【００１８】
通電機構４７ａは、本体フレーム４１の上フレーム部材４１４に絶縁させて固定されかつ導電板４５２ａと電気的に導通されている固定導体４７１と、焼結機の側部に配置された可動導電体４７２と、可動導電体４７２と焼結機の可動電極すなわち下通電電極２５に電気的に接続する接続端子４８ａとを電気的に接続するＬ形の導体４７３と、固定導電体４７１と可動導電体４７２とを電気的に接続するフレキシブル導電体４７４と、可動導電体４７２を下通電電極の上下動に同期して上下動させるアクチュエータ４７５とを備えている。アクチュエータ４７５は、この実施例では、焼結機２に隣接して直立状態で配置されたエアシリンダーなどの流体圧シリンダで構成され、そのピストンロッドの先端が可動導電体４７２に電気的に絶縁して取り付けられている。フレキシブル導電体４７４は、この実施例では極めて薄い幅広の銅板を多数枚重ねて可撓性を与えたものである。しかし、細い銅線を帯状に編んで可撓性を与えたものでも、或いは銅でできた多数枚のリンクを幅方向（図６で紙面に直角の方向）及び長手方向に並べれそれらをチエーンのように銅のような導電性の良いピンで接続した構造にしたものでもよい。いずれにしろ十分な電流を流せるように幅広にかつ大きな断面積を有する導電体として構成される。この通電切換え装置においてこのような通電機構を設けた理由は次のような理由による。すなわち、通電焼結機が大電流を必要とするためフレキシブル導電体の重量が非常に大きくなってしまい、下通電電極に偏荷重が作用し下通電電極を移動可能に案内している絶縁性案内部材の偏摩耗を発生させ、その結果焼結型設置テーブル部の上下の平行度を損ない通電焼結時のパルス電流の流れが不均一となって焼結のバラツキ、未焼結部分の発生などの不具合が発生し、また焼結型や焼結装置の破損問題などを引き起こす原因となるからである。
【００１９】
第１及び第２の入力側端子板及び第１及び第２の出力側端子板の上方、特に入力側端子板と出力側端子板とが横方向に（図８において左右方向に）重なり合う部分の上方には支持板５１が複数の支柱５２によりほぼ水平になるように配設され固定される。支柱５２は図示しない絶縁部材により入力側及び出力側端子板から電気的に絶縁され、したがって支持板５１も絶縁されている。支持板５１には複数（本実施例では４個）の流体シリンダ５３（５３ａ、５３ｂ、５３ｃ、５３ｄ）が直立状態で取り付けられている。流体シリンダ５３の位置は、各流体シリンダの軸心が入力端子板と出力端子板とが横方向に重なり合う部分のほぼ中央の線Ｘ−Ｘ（図８において）上でかつ入力端子板と出力端子板との間の位置、すなわち入力側端子板４２と二つの出力側端子板４４ａ及び４４ｂとの間の二つの位置並びに入力側端子板４３と二つの出力側端子板４５ａ及び４５ｂとの間の二つの位置になるように、決められている。また、各流体シリンダはそのピストンロッドが支持板の下側に突出できるように配向されている。各流体シリンダ５０のピストンロッド５３１には可動支持体５４（５４ａ、５４ｂ、５４ｃ、５４ｄ）（ただし図７では５４ｃのみ図示）が絶縁部材を介して電気的に絶縁して固定されている。各可動支持体５４の下面には銅等の導電性の良い材料でできた導通部材５５（５５ａ、５５ｂ、５５ｃ、５５ｄ）が固定されている。導通部材の下側の接触面すなわち通電面はほぼ水平になるように調整されている。このように、各流体シリンダに対して一つの導通部材が設けられ、各導通部材が対応する流体シリンダにより独立して上下動されるようになっている。導通部材５５ａはシリンダ５３ａにより動作されて第１の入力側端子板４２と第１の出力側端子板４４ａとを電気的に接続する。導通部材５５ｂはシリンダ５３ｂにより動作されて第１の入力側端子板４２と第１の出力側端子板４４ｂとを電気的に接続する。導通部材５４ｃはシリンダ５３ｃにより動作されて第２の入力側端子板４３と第２の出力側端子板４５ａとを電気的に接続する。導通部材５５ｄはシリンダ５３ｄにより動作されて第２の入力側端子板４３と第２の出力側端子板４５ｂとを電気的に接続する。
【００２０】
上記通電切換え装置４は、シリンダ５０ａ及び５０ｃが同時に動作して導通部材５２ａ及び５２ｃを押し下げて一方の導通部材５２ａを第１の入力側端子板４２と第１の出力側端子板４４ａに接触させてそれらを電気的に導通させ、他方の導通部材５２ｃを第２の入力側端子板４３と第２の出力側端子板４５ａに接触させてそれらを導通させ、それによって電源装置３から第１の通電焼結機２ａに直流パルス電流を供給する。一方第２の通電焼結機２ｂに直流パルス電流を供給するときには、シリンダ５０ｂ及び５０ｄが同時に動作して導通部材５２ｂ及び５２ｄを押し下げて一方の導通部材５２ｂを第１の入力側端子板４２と第１の出力側端子板４４ｂに接触させてそれらを電気的に導通させ、他方の導通部材５２ｄを第２の入力側端子板４３と第２の出力側端子板４５ｂに接触させてそれらを導通させる。
【００２１】
図１において、供給コンベア６及び排出コンベア８は、焼結型をベルト上に載せて搬送する公知の構造のベルトコンベアでも或いはガイドレール上に移動可能に載せられた焼結型をチエーンに取り付けられた送り部材で押して搬送する公知の構造のチエーンコンベアでもよいので、構造及び動作の詳細な説明は省略する。供給コンベア６は粉末の被焼結材が予め充填された焼結型ａを通電焼結機に近い供給位置に供給するコンベアであり、排出コンベア８は焼結が完了し、通電焼結機から装填装置により取り出された焼結型を排出する。
【００２２】
図１及び図２において、装填装置７は、固定台７１と、固定台７１に鉛直軸線Ｏ−Ｏを中心として少なくとも角θ回動するように支持された可動台７２と、その可動台の凸部に動作可能に取り付けられたアーム組立体７３と、アーム組立体の先端に取り付けられたチャック７４とを備え、可動台７２とアーム組立体７３でチャックを焼結型のある位置に接近させ、チャック７４で焼結型を把持して通電焼結機に装填し或いは通電焼結機から取り出すようになっている。なお、上記のような装填装置は工業用ロボット装置として一般的に知られているものでよいので、構造及び動作の詳細な説明は省略する。
【００２３】
上記実施例の通電焼結システムの動作を説明する。
パルス通電焼結機２ａ又は２ｂの上、下ハウジング組立体２３、２２がそれぞれ上位置及び下位置になっていて、下通電電極１４１が上通電電極から最も離れた状態になっているとき、粉末材料ｊが充填された焼結型ａが供給コンベア６により供給位置に送られて来ると、装填装置７が動作してチャック７４でその焼結型を把持し一方のパルス通電焼結機、例えば２ａの下通電電極１４１のヘッド２４４の上にセットされる。するとそのパルス通電焼結機２ａの駆動装置２６が動作して下ハウジング組立体２２及び下通電電極組立体２４を、焼結型の穴内に挿入された上プレスコアｃが上通電電極２５１のヘッド２５４の下面に当たるまで上昇させる。それと同時又はその後アクチュエータ２７が動作して上ハウジング組立体２３を降下させる。すると上ハウジング２３３のリング部材２３６と下ハウジング２２３のリング部材２２６とが当接して上、下ハウジングによって画成されるチャンバを外気と遮断し、そのチャンバ内を公知の方法で真空雰囲気又は不活性ガス雰囲気にする。その後駆動装置２６で下通電電極２４１を上通電電極２５１に向かって所望の圧力で押圧した状態で通電切換え装置４のシリンダ５３ａ及び５３ｃが同時に動作して導通部材５５ａ及び５５ｃを押し下げて一方の導通部材５５ａを第１の入力側端子板４２と第１の出力側端子板４４ａに接触させてそれらを電気的に導通させ、他方の導通部材５５ｃを第２の入力側端子板４３と第２の出力側端子板４５ａに接触させてそれらを導通させ、それによって電源装置３から第１の通電焼結機２ａに直流パルス電流を供給し、通電焼結機２ａで焼結を行う。所定時間通電して焼結が完了すると上、下ハウジング組立体２２及び２３が互いに離れて上、下ハウジングが離れると共に下通電電極２４１も降下し、図４に示される状態になる。すると装填装置が動作してチャック７４により焼結済みの焼結型を排出コンベアに移す。第２の通電焼結機２ｂで焼結を行う場合にはその通電焼結機２ｂについて上記と同様の動作を行う。なお、焼結型内への粉体の充填、充填された粉体の予備加圧などの準備動作は、通電焼結機が通電焼結動作を行っている間に供給コンベアの上流側に設けられた自動粉体充填装置で自動的に、或いは人手により行われる。
【００２４】
図９において、通電切換え装置の変形例の一部が示されている。この変形例では各可動支持体５３ａ’、５３ｂ’（２個のシリンダ及び可動支持体等しか図示せず）は支柱５２に移動可能に案内され、したがってそれら可動支持体に取り付けられた導通部材の動作の安定性を確保できる。なお、上記実施例では一つの入力側端子板に対して二つの出力側端子板を配置した例を示したが、図１０に示されるようにして一つの入力側端子板４２及び４３に対して三つの出力側端子板４４ａ、４４ｂ、４４ｃ及び４５ａ、４５ｂ、４５ｃを配置することも、配置を変えてそれ以上配置することも可能である。
【００２５】
上記実施例のパルス通電焼結機では上、下ハウジングが可動に構成されているが、図１１に示されるように、ハウジングを固定式にしてもよい。図１１において、前記実施例のパルス通電焼結機のハウジングと違ってハウジング２２３ｂは上支持板２１３ｂに固定された固定式である点で相違する。ハウジング２２３ｂは上端が上支持板２１３ｂに固定された中空の筒体２２５ｂと、中空の筒体２２５ｂの下端に固定された底板２２４ｂとを備えている。下通電電極組立体２４ｂは、駆動装置２６ｂを構成する流体シリンダ２６１ｂのピストンロッド２６２ｂの上端に取り付けられている。下通電電極組立体２４ｂは下端にフランジ部２４３ｂが形成された円柱状の電極本体２４２ｂから構成された下通電電極２４１ｂを備えている。電極本体２４２ｂと、ピストンロッド２６２ｂの上端に固定された接続ブロック２６３ｂとの間には、前記実施例と同様に絶縁板と銅板等でできた接続端子４８ａとが絶縁板を接続ブロック側にして配置固定されている。接続端子、電極本体及び接続ブロック間の接続方法は前記実施例と同じである。上電極組立体２５ｂの構造及び取り付け方法は前記実施例と実質的に同じである。従って説明は省略する。この実施例ではハウジング１２ｂが固定式であるため、ハウジング内の焼結チャンバ内への或いはそこからの焼結型の出し入れを行うための比較的大きな窓２２７ｂが形成され、その窓を蝶番等により開閉可能に取り付けたれたカバー２２８ｂにより閉鎖できるようにしてある。下通電電極２４１ｂはハウジング２２３ｂの底板２２４ｂに形成された穴を貫通して伸びている。その穴内には絶縁シール部材２２９ｂが設けられている。この絶縁シール部材は底板と下通電電極との間の電気的接続を阻止すると共に下通電電極の周りでの気密性を確保し、更に下通電電極をハウジングに関して移動可能に案内する役目をしている。このようなハウジング構造を有する場合には、絶縁シール部材が通電電極と滑り接触しているので偏荷重により偏摩耗を来すことになるが、本発明の通電装置を使用すればこのような偏摩耗も防止できる。なお、ハウジングの側壁は、前記実施例と同様に、環状体２２５ｂを二重に設けることによって二重壁構造（ウオータージャケット状）にされ、中に冷却水を通す構造になっている。また、扉２２８ｂも二重構造になっている。また、図示しないが、通電時の焼結型からの発熱からハウジングの内壁を保護するために、チャンバ内部に単層又は複数の層の環状のステンレス鋼薄板を遮熱板として設けてもよい。
【００２６】
【効果】
本発明によれば、
（イ）一つの電源装置で複数の通電焼結機を動作させることが可能であり、焼結機を効率よく運転でき、焼結コストを低減できる、
（ロ）電源装置の少なくして設置スペースの節約、システム全体の構成の簡素化等により設備費を節約でき、この点からも焼結コストを低減できる、
（ハ）焼結型の供給コンベア、排出コンベア及び装填装置を併用することにより複数の焼結機を連続して自動運転でき、焼結作業の能率を向上でき、また作業の無人化及び安全性の確保に寄与する、
（ニ）各焼結機毎の単独使用も、また焼結機の増設も可能でシステムの組み替えが容易である、
等の効果を奏することが可能である。
【図面の簡単な説明】
【図１】本発明のマルチヘッド通電焼結システムの一実施例の全体配置を示す概略平面図である。
【図２】装填装置の側面図である。
【図３】パルス通電焼結機の側面図である。
【図４】［Ａ］は下通電電極と駆動装置との連結状態を示す拡大断面図であり、［Ｂ］は上ハウジング組立体を動作するアクチュエータを示す図であり、［Ｃ］はアクチュエータの変形例を示す図である。
【図５】通電切換え装置の平面図であって、一方の通電焼結機と共に示す図である。
【図６】通電切換え装置の一部を他の通電焼結機と共に示す図であって、図５の右に連続する図である。
【図７】通電切換え装置の立面図であって図５の線Ａ−Ａに沿って見た図である。
【図８】入力側端子板と出力側端子板との配置位置関係を示す図である。
【図９】通電切換え装置の変形例の一部を示す側面図である。
【図１０】入力側端子板と出力側端子板との配置位置関係の変形例を示す図である。
【図１１】パルス通電焼結機の変形例を示す図である。
【符号の説明】
１マルチヘッド通電焼結システム２パルス通電焼結機
３電源装置４通電切換え装置
６焼結型供給コンベア７装填装置
２１本体フレーム２２流体圧シリンダ
２３下可動フレーム２４上可動フレーム
２５下通電電極２６上通電電極
４１本体フレーム４２、４３入力端子板
４４、４５出力端子板４６電極端子
４７ａ通電機構５１支持板
５２支柱５３流体シリンダ
５４可動支持体[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a multi-head pulse electric current sintering system (here, the multi-head means a portion for performing a plurality of sintering, in this embodiment, a sintering machine is provided), and more specifically, The present invention relates to a multi-head pulse current sintering system in which current sintering is efficiently performed by sequentially supplying a pulse current for sintering to a plurality of pulse current sintering machines from a single power supply device.
[0002]
Conventional electric current sintering requires a long sintering time, and the time required for supplying the sintering mold to the sintering apparatus is considerably shorter than the sintering time. For this reason, it is necessary to provide one power supply device for one supply device.
[0003]
By the way, in recent years, improvements have also been made in current sintering, for example, pulse current conduction that uses pulse current to perform sintering, including, for example, discharge plasma sintering, discharge sintering, or plasma activated sintering proposed by the present applicant. It has become possible to significantly shorten the sintering time by pressure sintering. For this reason, the time required for one sintering, that is, the sintering time, is the filling of the powder into the sintering mold, the supply of the sintering mold into the sintering apparatus or the removal of the sintering mold therefrom, Compared to the work time required for the attached preparatory work such as extraction of the sintered product from the sintering mold, it has become much less than conventional. Therefore, it is not always necessary to provide one power supply device for one sintering machine as in the case of conventional electric current sintering. Sintering work is performed by operating a plurality of sintering machines with one power supply device. It has come to be expected to improve the efficiency of.
[0004]
On the other hand, in pulse current sintering, the electric power necessary for sintering requires a low voltage (usually 100 V or less) and a large current (for example, 5000 A or more). For this reason, the power supply device is different from the power supply device used in the conventional current sintering and becomes an expensive device. Therefore, if a plurality of sintering machines can be operated with a small number of power supply devices, it is preferable to simplify the sintering equipment, save space, and further reduce the sintering cost.
[0005]
[Problems to be solved by the invention]
The problem to be solved by the present invention is to provide a multi-head pulse current sintering system in which a plurality of sintering machines can be operated by a single power supply device.
Another problem to be solved by the present invention is that a special power source switching device is provided so that a plurality of pulse current sintering machines that require low voltage and large current can be operated by one power source device. Is to provide a multi-head pulse current sintering system.
[0006]
[Means for Solving the Problems]
A multi-head pulse current sintering system according to the present invention includes a power supply device,
A plurality of pulsed electric sintering machines that are electrically connectable to one power supply unit and receive pulsed current for sintering from the power supply unit to perform pulsed electric sintering;
An energization switching device that is electrically connected to the power supply device and the plurality of pulse energization sintering machines and selectively supplies a pulse current from the power supply device to one of the plurality of pulse energization sintering machines; With
The energization switching device includes first and second input side terminal plates having flat energization surfaces connected to a power supply device, and the first input side terminal plate connected to the pulse energization sintering machine. A plurality of first output side terminal plates having flat current-carrying surfaces arranged adjacent to each other, and a flat surface connected to the pulse current sintering machine and arranged adjacent to the second input-side terminal plate A plurality of second output-side terminal plates having various current-carrying surfaces, and the first input-side and output-side terminals arranged adjacent to and in contact with the first input-side and output-side terminal plates A plurality of first communication members having a flat current-carrying surface in surface contact with the current-carrying surface of the plate, and arranged adjacent to the second input-side and output-side terminal plates so as to be in contact with them; A plurality of second communication members having flat current-carrying surfaces that are in surface contact with the current-carrying surfaces of the input side and output side terminal plates; Equipped and are configured.
[0007]
In the above-mentioned electric sintering system, a supply conveyor for supplying a sintering mold filled with a material to be sintered to a position close to the pulse electric sintering machine, and a sintering mold supplied by the supply conveyor for the pulse electric sintering machine And a loading device for loading. Furthermore, you may provide the automatic powder filling apparatus which fills powder in a sintering type | mold. Further, the power supply device may supply a high-current DC pulse current at a low voltage. Further, the energization switching device includes an actuator provided separately for each of the first and second communication members, and a second one associated with any one of the first communication members and the first communication member. The first and second input side and output side terminal plates may be pressed by an actuator provided with a communication member separately. Furthermore, the current-carrying surfaces of the input side terminal plate, the output side terminal plate, and the communication member are substantially horizontal, and each actuator is composed of a fluid cylinder disposed above each communication member, and the communication member is a piston of the cylinder. It may be attached to the rod via an insulator.
[0008]
An energization switching device for a pulse energization sintering machine according to the present invention is connected to the first and second input side terminal plates having flat energization surfaces connected to a power supply device, and the pulse energization sintering machine. A plurality of first output side terminal plates having a flat current-carrying surface disposed adjacent to the first input-side terminal plate; and the second input-side terminals connected to the pulse current sintering machine A plurality of second output side terminal plates having a flat current-carrying surface disposed adjacent to the plate, and disposed adjacent to the first input side and output side terminal plates so as to be in contact therewith, A plurality of first communication members having flat current-carrying surfaces that are in surface contact with the current-carrying surfaces of the first input side and output side terminal plates, and adjacent to and in contact with the second input side and output side terminal plates A flat energizing surface that is arranged to be in surface contact with the energizing surfaces of the second input side and output side terminal boards. A plurality of second communication members, and an actuator that is provided separately for each of the first and second communication members and moves the communication members toward the input side and output side terminal plates. Has been.
[0009]
The energization switching device includes an energization device that electrically connects the first and second output side terminal plates and the movable electrode of the pulse energization sintering machine, and the energization device is electrically connected to the movable electrode. A movable electrode side connection terminal that is connected and moves together with the movable electrode; and a flexible conductor that electrically connects the movable electrode side connection terminal and the first or second output side terminal plate. Also good. The energization device may include an actuator that vertically moves a connector that electrically connects the connection terminal on the movable electrode side and the flexible conductor in response to the vertical movement of the movable electrode.
【Example】
[0010]
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 schematically shows one embodiment of a multi-head pulse current sintering system according to the present invention. A multi-head pulsed electric sintering system (hereinafter simply referred to as an electric current sintering system) 1 of this embodiment has two first and second pulse electric current sintering machines (hereinafter simply referred to as an electric current sintering machine) 2 ( 2a, 2b), a power supply device 3 for supplying a pulse current to the energization sintering machine 2, and a pulse current from the power supply device that is electrically connected to the power supply device 3 and An electrification switching device 4 that selectively supplies to one, a sintering mold supply conveyor 6 that supplies a sintering mold filled with a powder material to a feeding position near the electrification sintering machine 2, and a feeding position. A loading device 7 for loading the sintered mold into the electric sintering machine, a discharge conveyor 8 for transporting the sintered sintering mold, and an automatic powder filling device 9 for filling the sintering mold with powder. Provided, and they are arranged in the positional relationship shown in FIG.
[0011]
3 and 4, the electric current sintering machine 2 (2a, 2b) of this embodiment includes a table 211 and a plurality of (two in this embodiment) support columns 212 fixed to the table in an upright state. And a main body frame 21 having an upper support plate 213 fixed to the upper end of the column 212, a lower housing assembly 22 supported by the column 212 so as to be movable up and down, and an upper housing group supported by the column 212 so as to be movable up and down. A solid body 23, a lower energizing electrode assembly 24 attached to the lower housing assembly 22, an upper energizing electrode assembly 25 provided to be attached to the upper support plate 213, and the center of the base 211. And a driving device 26 for moving the lower movable housing assembly up and down. The lower housing assembly 22 includes a disc-like (in this embodiment) lower movable body 221 that is slidably guided and supported by the support column 212 via bearings 222, and a lower housing 223 attached to the lower movable body 221. have. The housing 223 forms a bottom wall and is attached to the lower movable body 221, a bottom plate 224 that is connected to the bottom plate 224 by welding or the like, and an annular body 225 that forms an annular (annular) side wall, and an annular shape And a ring member 226 fixed to the upper end of the plate. The upper housing assembly 23 includes a ring-shaped upper movable body 231 that is slidably guided and supported by a column 212 via a bearing 232, and an upper housing 233 attached to the upper movable body 231. The upper housing is fixed to the top plate 234 that constitutes the upper wall, the annular body 235 that constitutes the annular (annular) side wall, and the lower end of the annular plate and the upper movable body. And a ring member 236 attached to the upper movable body. The upper and lower housings 233 and 223 cooperate with each other to define a sintering chamber. The upper and lower housings are formed into a double wall structure (water jacket shape) by providing the annular bodies 235 and 225 in a double manner, and the cooling water is allowed to pass therethrough. This sintering chamber is controlled to a sintering atmosphere such as a vacuum atmosphere or an inert gas atmosphere by an apparatus (not shown). A seal ring is provided on at least one of the upper surface of the ring member 226 and the lower surface of the ring member 236 so as to ensure airtightness between these surfaces. Although not shown, a viewing window may be provided on the annular body 235 of the upper housing so that the inside of the sintering chamber can be seen from the outside. Although not shown, in order to protect the inner wall of the housing from heat generation from the sintering mold when energized, a single layer or a plurality of layers of an annular stainless steel thin plate may be provided inside the chamber as a heat shield.
[0012]
The lower energizing electrode assembly 24 is formed on the lower movable body 221 and the bottom plate 224 via the insulating bush 246 and the insulating plate 247 in the vertical through hole formed in the central portion of the lower movable body 221 and the bottom plate 224 of the lower housing. A lower energizing electrode 241 is provided which is fixed in an electrically insulated state. In this embodiment, the lower energizing electrode 241 includes a cylindrical electrode body 242 having a flange portion 243 at the lower end, and an electrode head 244 attached to the upper end of the electrode body 242. Although not shown, a cooling passage is formed in the lower energizing electrode 241. The cooling passage is connected to an external coolant supply source and allows the coolant to flow therethrough. As shown in FIG. 4A, the lower energization electrode 241 is fixed to the lower movable body by attaching the flange portion 243 to the lower movable body 221 with a fixing bolt 248. In this case, electrical insulation between the lower energizing electrode 241 and the lower movable body 221 is secured around the fixing bolt 248 using a known insulating sleeve, insulating washer, and the like. The upper energizing electrode assembly 25 is fixed in a vertically through hole formed at the center of the upper support plate 213 in a state of being electrically insulated from the upper support plate 213 via insulating bushings 256 and 257. An upper energizing electrode 251 is provided. In this embodiment, the upper energizing electrode 251 has a long cylindrical electrode body 252 with a flange portion 243 fixed to the upper end, and an electrode head 253 attached to the lower end of the electrode body 252. Although not shown, a cooling passage is formed inside the lower energizing electrode 251 and is connected to an external coolant supply source and allows the coolant to flow therethrough. Although not shown, the upper energization electrode 251 is fixed to the upper support plate by attaching the flange portion 253 to the upper support plate 213 with a fixing bolt. In this case, electrical insulation between the upper energizing electrode 251 and the upper support plate 213 is secured around the fixing bolt by using a known insulating sleeve and insulating washer. The upper energizing electrode 251 extends through a hole that vertically penetrates the top plate 234 of the upper housing 233, and the lower end is arranged in the sintering chamber. An insulating bush 238 and a seal member 239 are attached to the top plate 234. The axis of the lower energizing electrode 241 and the axis of the upper energizing electrode 251 are positioned so as to be coaxial.
[0013]
In this embodiment, the driving device 26 is composed of a fluid pressure cylinder 261, and a connection block 263 for fixing to the lower energizing electrode is fixed to the tip (upper end in the figure) of the piston rod 262. A connection method between the connection block 263 and the piston rod 262 is performed by screwing a male screw formed on the tip of the piston rod with a female screw formed on the connection block. Between the connection block 263 and the lower energization electrode 241, a connection terminal 48a made of a conductive material such as a copper plate, which will be described later, and an insulating plate 264 are arranged with the connection terminal in contact with the lower energization electrode. ing. As shown in FIG. 4A, the connection block 263 is fixed to the lower energization electrode by attaching the connection block 263 to the flange portion 243 of the lower energization electrode 241 with a fixing bolt 266. In this case, electrical insulation between the connection block 263 and the lower energization electrode 241 around the fixing bolt 266 is ensured by using a known insulating sleeve, insulating washer, and the like. The lower housing assembly 22 is moved up and down by the driving device 26 together with the lower energizing electrode assembly 24 in this way. In the above embodiment, a fluid pressure cylinder is used as the driving device. However, instead of this, a method of driving with an electric motor may be adopted. A connection terminal 58 made of a conductive material such as a copper plate, which will be described later, is disposed between the flange portion 253 of the upper energizing electrode 251 and the insulating bush 257. As shown in FIG. 4B, the mechanism for moving the upper housing assembly 23 up and down includes an actuator 27 having an upper end fixed to the upper support plate 213 and a lower end fixed to the upper movable body 231. In this embodiment, the actuator 27 is composed of a fluid cylinder 271. The upper end of the cylinder body of the fluid cylinder is fixed to the upper support plate 213, and the lower end of the piston rod 272 is fixed to the upper movable body 231. The actuator is positioned so that its axis is in a plane that forms a predetermined angle, for example, 30 degrees or 45 degrees with respect to the plane including the axis of the pair of support columns 212 and the axes of the upper and lower energizing electrodes 251 and 241. Has been.
[0014]
In the pulse energization sintering machine, when the upper and lower housing assemblies 23 and 22 are in the upper position and the lower position, respectively, and the lower energization electrode 241 is in the state farthest from the upper energization electrode 25, the lower On the head 244 of the current-carrying electrode 241, a sintering mold a filled with a powder material j, which is a material to be sintered, is placed. At this time, the upper surface of the head 244 of the lower energizing electrode 241 is brought into contact with the lower surface of the lower press core b inserted and set in the sintered mold hole and can be energized with it, and a desired pressure can be applied. When the sintering mold is positioned on the lower energizing electrode 241, the driving device 26 operates to move the lower energizing electrode assembly 24 and the sintering mold a thereon together with the lower housing assembly 22. The upper press core c inserted into the hole is raised until it hits the lower surface of the head 254 of the upper energizing electrode 251. At the same time or thereafter, the actuator 27 operates to lower the upper housing assembly 23. Then, the ring member 236 of the upper housing 233 and the ring member 226 of the lower housing 223 come into contact with each other, and the chamber defined by the lower housing is shut off from the outside air. Use a gas atmosphere. Thereafter, the drive device 26 presses the lower energization electrode 241 toward the upper energization electrode 251 with a desired pressure, and a DC pulse current having a desired value is passed through the energization electrode to perform pulse energization sintering. In the above embodiment, the actuator 27 that moves the upper housing assembly 23 up and down is constituted by a fluid cylinder. However, as shown in FIG. 4C, a screw shaft and a nut mechanism comprising a screw shaft and a nut screwed therewith. You may comprise by 271a. The screw shaft and nut mechanism 271a includes a screw shaft 272a that is rotatably supported by the lower movable body 221 in an upright state and has a male screw formed over almost the entire length, and a female screw that is screwed with the male screw of the screw shaft 272a. And a drive motor 274a that rotates the screw shaft 272a.
[0015]
The power supply device 3 is preferably one that can supply a DC pulse current of a large current (for example, 5000 A or more) at a low voltage (for example, 100 V or less). This is because, when performing pulsed current sintering such as discharge plasma sintering, discharge sintering or plasma activated sintering, a low voltage and large DC pulse current is required. In addition, since the structure itself of such a direct current pulse generation power supply device may be well-known, the detailed description is abbreviate | omitted.
[0016]
5 to 8, the energization switching device 4 of the present embodiment is shown. The energization switching device 4 of this embodiment is configured to supply a pulse current to two energization sintering machines with one power supply device. The energization switching device 4 includes first and second input side terminal plates 42 and 43 that are electrically insulated and fixed to the base plate via an insulator 412 on the base plate 411 of the main body frame 41. ing. The upper surface of the base plate 411, and therefore the upper surface of the insulator 412 is adjusted to be substantially horizontal, and therefore the upper contact surfaces of the input terminal plates 42 and 43, that is, the current-carrying surfaces 421 and 431 are also formed on a substantially horizontal and flat surface. Has been. These input-side terminal boards are made of a material having good conductivity such as copper, and two wide boards that can take a large area as a current-carrying surface are stacked (to ensure a large current-carrying capacity). The first and second input terminal plates 42 and 43 are similarly connected to the power supply device via wide and plate-like conductive plates 422 and 432, respectively. These conductive plates are also made of a highly conductive material such as copper.
[0017]
On the insulator 412 on the base plate 411, a pair of first input side terminal plates 42 (on the left and right sides in FIG. 5) is separated (electrically insulated) from the input side terminal plates. The first output side terminal plate 44 (44a, 44b) is fixed, and is separated from the input side terminal plate on both sides (left and right sides in FIG. 5) of the second input side terminal plate 43 (electrically insulated). A pair of second output side terminal plates (45a, 45b) 45 are fixed. The contact surfaces on the upper side of the output side terminal plates 44 and 45, that is, the energizing surfaces 441 and 451, are also formed to be substantially horizontal and flat, and to be flush with the energizing surface of the input side terminal plate. These output side terminal boards are made of a material having good conductivity, such as copper, and are formed by stacking two wide boards that can take a large area as a current-carrying surface. One of the first pair of output side terminal plates 44a is electrically connected to the upper energization electrode of the first energization sintering machine 2a through a plurality of conductive plates 442a and 443a which are also wide and plate-like. Is connected to the connection terminal 46a. The other first output side terminal plate 44b is electrically connected to the upper energization electrode of the second energization sintering machine 2b through a plurality of conductive plates 442b and 443b which are similarly wide and plate-like. It is connected to the electrode terminal 46b. The conductive plates 442a, 442b, 443a, and 443b are also configured by stacking a plurality of conductive plates such as copper. One side 45a of the second pair of output terminal plates is electrically connected to one (first electric sintering machine 2a side) energization mechanism 47a through a plurality of similarly wide and plate-like conductive plates 452a. ing. The other second output terminal plate 45b is electrically connected to an energization mechanism (not shown) on the other side (the first energization sintering machine 2b side) via a plurality of plate-shaped conductive plates 452b that are similarly wide. It is connected. Since the two energization mechanisms have exactly the same structure and operation, only one 47a will be described below.
[0018]
The energization mechanism 47a is insulated and fixed to the upper frame member 414 of the main body frame 41 and is electrically connected to the conductive plate 452a, and a movable conductor 472 disposed on the side of the sintering machine. An L-shaped conductor 473 that electrically connects the movable conductor 472 and the movable electrode of the sintering machine, that is, the connection terminal 48a that is electrically connected to the lower energizing electrode 25, the fixed conductor 471, and the movable conductor 472. And the actuator 475 that moves the movable conductor 472 up and down in synchronization with the vertical movement of the lower energization electrode. In this embodiment, the actuator 475 is composed of a fluid pressure cylinder such as an air cylinder arranged upright adjacent to the sintering machine 2, and the tip of the piston rod is electrically insulated from the movable conductor 472. Attached. In this embodiment, the flexible conductor 474 is made by stacking a large number of extremely thin copper plates to give flexibility. However, even if a thin copper wire is knitted into a belt shape to give flexibility, a large number of links made of copper are arranged in the width direction (perpendicular to the plane of the paper in FIG. 6) and the longitudinal direction, and these are linked to the chain. In this way, a structure in which a pin having good conductivity such as copper is connected may be used. In any case, it is configured as a conductor having a wide and large cross-sectional area so that a sufficient current can flow. The reason why such an energization mechanism is provided in the energization switching device is as follows. In other words, since the current-sintering machine requires a large current, the weight of the flexible conductor becomes very large, and an insulative guide that guides the lower current-carrying electrode so that it can be moved by applying an unbalanced load to the lower current-carrying electrode. Causes uneven wear of the members, resulting in loss of parallelism of the upper and lower parts of the sintering mold installation table, resulting in non-uniform flow of pulse current during current sintering, unevenness in sintering, generation of unsintered parts, etc. This is because the above-mentioned trouble occurs and causes a problem of damage to the sintering mold and the sintering apparatus.
[0019]
Above the first and second input side terminal plates and the first and second output side terminal plates, in particular, the portion where the input side terminal plate and the output side terminal plate overlap in the lateral direction (in the horizontal direction in FIG. 8). A support plate 51 is disposed and fixed above the plurality of support columns 52 so as to be substantially horizontal. The support column 52 is electrically insulated from the input side and output side terminal plates by an insulating member (not shown), and thus the support plate 51 is also insulated. A plurality (four in this embodiment) of fluid cylinders 53 (53a, 53b, 53c, 53d) are attached to the support plate 51 in an upright state. The position of the fluid cylinder 53 is such that the axial center of each fluid cylinder is on a substantially central line XX (in FIG. 8) of the portion where the input terminal plate and the output terminal plate overlap in the lateral direction, and the input terminal plate and the output terminal. Between the input side terminal plate 42 and the two output side terminal plates 44a and 44b, and between the input side terminal plate 43 and the two output side terminal plates 45a and 45b. It is determined to be in two positions. Each fluid cylinder is oriented so that its piston rod can protrude below the support plate. A movable support 54 (54a, 54b, 54c, 54d) (however, only 54c is shown in FIG. 7) is electrically insulated and fixed to the piston rod 531 of each fluid cylinder 50 via an insulating member. A conductive member 55 (55a, 55b, 55c, 55d) made of a material having good conductivity such as copper is fixed to the lower surface of each movable support 54. The lower contact surface of the conducting member, that is, the energizing surface is adjusted to be substantially horizontal. Thus, one conducting member is provided for each fluid cylinder, and each conducting member is moved up and down independently by the corresponding fluid cylinder. The conducting member 55a is operated by the cylinder 53a to electrically connect the first input side terminal plate 42 and the first output side terminal plate 44a. The conducting member 55b is operated by the cylinder 53b to electrically connect the first input side terminal plate 42 and the first output side terminal plate 44b. The conducting member 54c is operated by the cylinder 53c to electrically connect the second input side terminal plate 43 and the second output side terminal plate 45a. The conducting member 55d is operated by the cylinder 53d to electrically connect the second input side terminal plate 43 and the second output side terminal plate 45b.
[0020]
In the energization switching device 4, the cylinders 50a and 50c operate simultaneously to push down the conducting members 52a and 52c so that the one conducting member 52a is brought into contact with the first input side terminal plate 42 and the first output side terminal plate 44a. And electrically connecting the other conductive member 52c to the second input side terminal plate 43 and the second output side terminal plate 45a to make them conductive. A direct current pulse current is supplied to the electric sintering machine 2a. On the other hand, when supplying a direct current pulse current to the second energization sintering machine 2b, the cylinders 50b and 50d operate simultaneously to push down the conducting members 52b and 52d so that the one conducting member 52b is connected to the first input side terminal plate 42. The first output side terminal plate 44b is brought into contact and electrically conducted, and the other conduction member 52d is brought into contact with the second input side terminal plate 43 and the second output side terminal plate 45b to conduct them. Let
[0021]
In FIG. 1, the supply conveyor 6 and the discharge conveyor 8 may be a belt conveyor having a known structure that conveys a sintered mold on a belt, or a sintered mold that is movably mounted on a guide rail is attached to a chain. Since it may be a chain conveyor of a known structure that is pushed and conveyed by a feeding member, a detailed description of the structure and operation is omitted. The supply conveyor 6 is a conveyor for supplying a sintering mold a pre-filled with a powdery material to be sintered to a supply position close to the electric sintering machine, and the discharge conveyor 8 is completed from the electric sintering machine. The sintered mold taken out by the loading device is discharged.
[0022]
1 and 2, the loading device 7 includes a fixed base 71, a movable base 72 supported by the fixed base 71 so as to rotate at least an angle θ about the vertical axis OO, and a convexity of the movable base. An arm assembly 73 operably attached to the head and a chuck 74 attached to the tip of the arm assembly, the movable base 72 and the arm assembly 73 approaching the chuck to a position where the sintered mold is located, The chuck 74 holds the sintering mold and loads it in the electric sintering machine or removes it from the electric sintering machine. In addition, since the above loading apparatus may be what is generally known as an industrial robot apparatus, detailed description of the structure and operation | movement is abbreviate | omitted.
[0023]
The operation of the current sintering system of the above embodiment will be described.
When the pulse energization sintering machine 2a or 2b and the lower housing assemblies 23 and 22 are in the upper position and the lower position, respectively, and the lower energization electrode 141 is in the state farthest from the upper energization electrode, When the sintering die a filled with the material j is sent to the supply position by the supply conveyor 6, the loading device 7 operates to hold the sintering die with the chuck 74, and one pulse current sintering machine, for example, 2a is set on the head 244 of the lower energizing electrode 141. Then, the drive device 26 of the pulse energization sintering machine 2a is operated to move the lower housing assembly 22 and the lower energization electrode assembly 24 into the head of the upper energization electrode 251 with the upper press core c inserted into the hole of the sintering mold. Raise until it hits the bottom of 254. At the same time or thereafter, the actuator 27 operates to lower the upper housing assembly 23. Then, the ring member 236 of the upper housing 233 and the ring member 226 of the lower housing 223 come into contact with each other, and the chamber defined by the lower housing is shut off from the outside air. Use a gas atmosphere. Thereafter, with the driving device 26 pressing the lower energizing electrode 241 toward the upper energizing electrode 251 with a desired pressure, the cylinders 53a and 53c of the energization switching device 4 operate simultaneously to push down the conducting members 55a and 55c, thereby conducting one conduction. The member 55a is brought into contact with the first input-side terminal plate 42 and the first output-side terminal plate 44a to electrically connect them, and the other conductive member 55c is connected to the second input-side terminal plate 43 and the second input-side terminal plate 43. The output side terminal plate 45a is brought into contact with each other, and thereby a DC pulse current is supplied from the power supply device 3 to the first current sintering machine 2a, and the current sintering machine 2a performs sintering. When the current is energized for a predetermined time and the sintering is completed, the upper housing assemblies 22 and 23 are separated from each other, the lower housing is separated, and the lower energizing electrode 241 is also lowered to be in the state shown in FIG. Then, the loading device operates to move the sintered sintered mold by the chuck 74 to the discharge conveyor. When sintering is performed by the second electric sintering machine 2b, the same operation as described above is performed for the electric sintering machine 2b. In addition, preparatory operations such as filling the powder into the sintering mold and pre-pressurizing the filled powder are provided on the upstream side of the supply conveyor while the current sintering machine performs the current sintering operation. The automatic powder filling apparatus is used automatically or manually.
[0024]
FIG. 9 shows a part of a modification of the energization switching device. In this modification, each movable support 53a ', 53b' (only two cylinders, movable support, etc. are shown) is movably guided to the support column 52, and therefore the conductive members attached to these movable supports Operation stability can be secured. In the above embodiment, an example in which two output side terminal plates are arranged with respect to one input side terminal plate is shown. However, as shown in FIG. It is possible to arrange the three output side terminal plates 44a, 44b, 44c and 45a, 45b, 45c, or to arrange more than that by changing the arrangement.
[0025]
In the pulse electric sintering machine of the above embodiment, the upper and lower housings are configured to be movable, but the housing may be fixed as shown in FIG. In FIG. 11, the housing 223b differs from the housing of the pulse current sintering machine of the above embodiment in that it is a fixed type fixed to the upper support plate 213b. The housing 223b includes a hollow cylinder 225b whose upper end is fixed to the upper support plate 213b, and a bottom plate 224b fixed to the lower end of the hollow cylinder 225b. The lower energizing electrode assembly 24b is attached to the upper end of the piston rod 262b of the fluid cylinder 261b constituting the driving device 26b. The lower energizing electrode assembly 24b includes a lower energizing electrode 241b composed of a cylindrical electrode body 242b having a flange portion 243b formed at the lower end. Between the electrode main body 242b and the connection block 263b fixed to the upper end of the piston rod 262b, a connection terminal 48a made of an insulating plate and a copper plate or the like is provided on the connection block side as in the above embodiment. The placement is fixed. The connection method among the connection terminal, the electrode body, and the connection block is the same as that in the above embodiment. The structure and attachment method of the upper electrode assembly 25b are substantially the same as those in the previous embodiment. Therefore, explanation is omitted. In this embodiment, the housing 12b is fixed, so that a relatively large window 227b is formed in and out of the sintering chamber in the housing, and the window is formed by a hinge or the like. It can be closed by a cover 228b attached so as to be openable and closable. The lower energizing electrode 241b extends through a hole formed in the bottom plate 224b of the housing 223b. An insulating seal member 229b is provided in the hole. The insulating seal member serves to prevent electrical connection between the bottom plate and the lower energizing electrode, to ensure airtightness around the lower energizing electrode, and to guide the lower energizing electrode to be movable with respect to the housing. Yes. In the case of such a housing structure, since the insulating seal member is in sliding contact with the energizing electrode, uneven wear occurs due to uneven load. Wear can also be prevented. In addition, the side wall of the housing has a double wall structure (water jacket shape) by providing double annular bodies 225b as in the above embodiment, and has a structure through which cooling water passes. The door 228b also has a double structure. Although not shown, in order to protect the inner wall of the housing from heat generation from the sintering mold when energized, a single layer or a plurality of layers of an annular stainless steel thin plate may be provided inside the chamber as a heat shield.
[0026]
【effect】
According to the present invention,
(A) It is possible to operate a plurality of current sintering machines with a single power supply device, the sintering machine can be operated efficiently, and the sintering cost can be reduced.
(B) Equipment costs can be saved by reducing installation space by reducing the number of power supply units, simplifying the overall system configuration, etc. From this point, sintering costs can be reduced.
(C) By using a sintering type supply conveyor, discharge conveyor and loading device in combination, a plurality of sintering machines can be operated continuously and automatically, the efficiency of the sintering operation can be improved, and the unmanned and safe operation. Contribute to ensuring
(D) Easy to reconfigure the system because each sintering machine can be used independently or the number of sintering machines can be increased.
It is possible to produce effects such as these.
[Brief description of the drawings]
FIG. 1 is a schematic plan view showing the overall arrangement of an embodiment of a multi-head electric current sintering system of the present invention.
FIG. 2 is a side view of the loading device.
FIG. 3 is a side view of a pulse current sintering machine.
4A is an enlarged cross-sectional view showing a connection state of the lower energization electrode and the driving device, FIG. 4B is a view showing an actuator that operates the upper housing assembly, and FIG. It is a figure which shows a modification.
FIG. 5 is a plan view of the energization switching device and is shown together with one energization sintering machine.
6 is a diagram showing a part of the energization switching device together with another energization sintering machine, and is a diagram continuing to the right of FIG. 5;
7 is an elevational view of the energization switching device as seen along line AA in FIG.
FIG. 8 is a diagram showing an arrangement positional relationship between an input side terminal plate and an output side terminal plate.
FIG. 9 is a side view showing a part of a modification of the energization switching device.
FIG. 10 is a diagram showing a modification of the arrangement positional relationship between the input side terminal plate and the output side terminal plate.
FIG. 11 is a view showing a modification of the pulse current sintering machine.
[Explanation of symbols]
1 Multi-head electric sintering system 2 Pulse electric sintering machine
3 Power supply device 4 Energization switching device
6 Sintering type supply conveyor 7 Loading device
21 Body frame 22 Fluid pressure cylinder
23 Lower movable frame 24 Upper movable frame
25 Lower conducting electrode 26 Upper conducting electrode
41 Body frame 42, 43 Input terminal board
44, 45 Output terminal board 46 Electrode terminal
47a Energizing mechanism 51 Support plate
52 Prop 53 Fluid cylinder
54 Movable support

Claims

A power supply;
A plurality of pulsed electric sintering machines that are electrically connectable to one power supply unit and receive pulsed current for sintering from the power supply unit to perform pulsed electric sintering;
An energization switching device that is electrically connected to the power supply device and the plurality of pulse energization sintering machines and selectively supplies a pulse current from the power supply device to one of the plurality of pulse energization sintering machines; With
The energization switching device includes first and second input side terminal plates having flat energization surfaces connected to a power supply device, and the first input side terminal plate connected to the pulse energization sintering machine. A plurality of first output side terminal plates having flat current-carrying surfaces disposed adjacent to each other, and a flat surface connected to the pulse current sintering machine and disposed adjacent to the second input-side terminal plate A plurality of second output-side terminal plates having various current-carrying surfaces, and the first input-side and output-side terminals arranged adjacent to and in contact with the first input-side and output-side terminal plates A plurality of first conductive members having a flat current-carrying surface that is in surface contact with a current-carrying surface of the plate; A plurality of second conductive members having flat current-carrying surfaces that are in surface contact with the current-carrying surfaces of the input side and output side terminal plates; It multihead pulse current sintering system comprising.

In the multi-head pulse current sintering system according to claim 1,
A supply conveyor for supplying a sintering mold filled with a material to be sintered to a position close to the pulse current sintering machine;
A multi-head pulse current sintering system comprising: a loading device for loading the sintering mold supplied by the supply conveyor into the pulse current sintering machine.

3. The multi-head pulse energization sintering system according to claim 1, wherein the power supply device supplies a high-current DC pulse current at a low voltage. 4.

4. The multi-head pulse energization sintering system according to claim 1, wherein the energization switching device includes an actuator provided separately for each of the first and second communication members. Any one of the communication members and the second communication member associated with the first communication member are pressed against the first and second input side and output side terminal plates by the separately provided actuators. Multi-head pulse current sintering system.

5. The multi-head pulse energization sintering system according to claim 4, wherein the energizing surfaces of the input side terminal plate, the output side terminal plate, and the communication member are substantially horizontal, and each actuator is disposed above each communication member. A multi-head pulse electric current sintering system comprising a fluid cylinder, wherein the communicating member is attached to a piston rod of the cylinder via an insulator.

In an energization switching device for a pulsed electric sintering machine, first and second input side terminal plates having flat energized surfaces connected to a power supply device, and the first electric current sintering machine connected to the pulsed electric sintering machine A plurality of first output side terminal plates having a flat current-carrying surface arranged adjacent to the input side terminal plate, and connected to the pulse current sintering machine and adjacent to the second input side terminal plate A plurality of second output side terminal plates having flat current-carrying surfaces arranged in contact therewith and adjacent to the first input side and output side terminal plates so as to be in contact therewith. A plurality of first communication members having flat current-carrying surfaces that are in surface contact with the current-carrying surfaces of the input side and output side terminal plates, and arranged adjacent to the second input side and output side terminal plates so as to be able to contact them. And a flat energizing surface that is in surface contact with the energizing surfaces of the second input side and output side terminal boards. A plurality of second communication members and an actuator provided separately for each of the first and second plurality of communication members and moving the communication members toward the input side and output side terminal plates. Switching device.

The energization switching device for a pulse energization sintering machine according to claim 6, further comprising an energization device for electrically connecting the first and second output side terminal plates and the movable electrode of the pulse energization sintering machine. The electrically conductive device is electrically connected to the movable electrode and moves together with the movable electrode. The movable electrode side connection terminal, the movable electrode side connection terminal, and the first or second output side terminal plate are electrically connected. Switching device comprising a flexible conductor to be electrically connected.

8. The energization switching device for a pulse energization sintering machine according to claim 7, wherein the energization device has a connector for electrically connecting the connection terminal on the movable electrode side and the flexible conductor to move the movable electrode up and down. Energization switching device comprising an actuator that moves up and down in response to.