JP4347944B2 - Production management method, method for securing the number of safe work in process on the production line, and production line - Google Patents

Description

【００１３】
により求め、
工程Ｐ_i の基準処理能力をＴ_i として、工程Ｐ_i の装置台数Ｃ_EPi を
【００１４】
【数３１】

【００１５】
により求め、
生産計画上、工程Ｐ_i において１日当たり必要な処理数をＮ_i 、Ｕ_d を他責稼働率として、工程Ｐ_i の必要装置台数Ｃ_ENi を
【００１６】
【数３２】

【００１７】
により求め、
装置Ｅ_j がＯ_fj日停止した場合に前記次工程で不足する製品個数を
【００１８】
【数３３】

【００１９】
により求め、前記Ｓ_ｉｊのうちの最大のものＳ_ｉ （Ｓ_ｉ ＝Ｍａｘ（Ｓ_ｉｊ，ｊ＝１，２・・・ｎ）に従って確保し、
さらに、前記工程Ｐ_ｉ の直前に、前記Ｓ_ｉ に対応する数の空き棚を確保することを特徴とする生産管理方法により、または
請求項２に記載したように、
前記空き棚の数は、前記工程Ｐ_ｉ の歩留まりをＢ_ｉ として、１００Ｓ_ｉ ／Ｂ_ｉ に従って決定されることを特徴とする請求項１記載の生産管理方法により、または
請求項３に記載したように、
前記装置の使用比率Ｒ_ｊｉは、前記工程Ｐ_ｉ において要求される処理能力Ｔ_Ｒｉを満たす範囲内において、前記安全仕掛かり数Ｓ_ｉ が最小化するように決定されることを特徴とする請求項１または２記載の生産管理方法により、または
請求項４に記載したように、
前記停止期間Ｏ_ｆｊは、SEMI E10-96
スタンダードに規定された計画オフライン時間と計画外オフライン時間のうち、長い方とすることを特徴とする請求項１または２記載の生産管理方法により、または
請求項５に記載したように、
前記停止期間Ｏ_ｆｊは、計画外オフライン時間の平均値ＭＴＵＯと、平均計画外ダウンタイム間隔ＭＴＵＤと、生産計画上での生産量の管理期間Ｐ日とから、ｋをSEMI E10-96 スタンダードに規定された平均故障間隔の信頼性の下限値として、
Ｏ_ｆｊ（日）＝ＭＴＵＯ・ｌｎ｛Ｐ／（ｋ・ＭＴＵＤ）｝
により求められることを特徴とする請求項１または２記載の生産管理方法により、または
請求項６に記載したように、
前記各工程Ｐ _ｉ において、装置Ｅ _ｊ の使用について前記工程Ｐ _ｉ で処理される製品の種類による制限が課せられる場合に、前記工程群Ｐ _ｉ （ｉ＝１，２・・・ｍ）のかわりに前記工程群を製品の種類別に細分割した工程品種群Ｐ _ｉ （ｉ＝１，２・・・ｚ）を定義し、前記工程品種群Ｐ _ｉ に含まれる工程品種の各々について、前記安全仕掛かりと基本仕掛かりとを計算する工程を含むことを特徴とする請求項１記載の生産管理方法により、 または
請求項７に記載したように、
工程Ｐ_ｉ を前記装置群Ｅ_ｊ （ｊ＝１，２・・・ｎ）が処理し、次工程Ｐ_ｉ＋１ を装置群Ｅ_ｋ （ｋ＝１，２・・・ｍ）が処理する生産ラインにおける生産管理方法であって、前記工程Ｐ_ｉ と前記工程Ｐ_ｉ＋１ との間に安全仕掛かりを設定できない場合に、仮想工程Ｐ_{ｉ，ｉ＋１} と仮想装置Ｅ_ｊｋとを定義し、前記仮想工程Ｐ_{ｉ，ｉ＋１} に対して安全仕掛かり数を、
仮想装置Ｅ_ｊ，ｋ の前記仮想工程Ｐ_{ｉ，ｉ＋１} に対する処理能力をＴ_ｊｋ，仮想装置Ｅ_ｊｋの、前記仮想工程Ｐ_{ｉ，ｉ＋１} に対する使用比率をＲ_ｊ，ｋ として、前記仮想工程Ｐ_{ｉ，ｉ＋１} の処理能力Ｔ_{Ｒｉ，ｉ＋１}を
【００２０】
【数３４】

【００２１】
により求め、
前記仮想工程Ｐ_i+1 の基準処理能力をＴ_i,i+1 として、前記仮想工程Ｐ_i,i+1 の装置台数Ｃ_EPi,i+1 を
【００２２】
【数３５】

【００２３】
により求め、
生産計画上、前記仮想工程Ｐ_i,i+1 において１日当たり必要な処理数をＮ_i,i+1 、Ｕ_d を他責稼働率として、前記仮想工程Ｐ_i,i+1 の必要装置台数Ｃ_ENi,i+1 を
【００２４】
【数３６】

【００２５】
により求め、
装置Ｅ_j がＯ_f 日停止した場合に前記次工程で不足する製品個数Ｓ_j0を
【００２６】
【数３７】

【００２７】
により求め、
装置Ｅ_k がＯ_f 日停止した場合に前記次工程で不足する製品個数Ｓ_0kを
【００２８】
【数３８】

【００２９】
により求め、前記Ｓ_ｊ０とＳ_ｏｋのうちの最大のものＳ_{ｉ，ｉ＋１} （Ｓ_{ｉ，ｉ＋１} ＝Ｍａｘ（Ｓ_ｊｏ，Ｓ_ｏｋ））に従って確保し、
さらに、前記工程Ｐ_ｉ の直前に、前記Ｓ_{ｉ，ｉ＋１} に対応する数の空き棚を確保することを特徴とする生産管理方法により、または
または
請求項８に記載したように、
【００３１】
工程群Ｐ_ｉ （ｉ＝１，２・・・ｍ）を含み、前記工程群に製品を流すことにより、装置群Ｅ_ｊ （ｊ＝１，２・・・ｎ）を使って前記製品に対して必要な加工を行なう生産ラインにおいて、一の工程Ｐ_ｉ と次の工程Ｐ_ｉ＋１ との間に、前記工程Ｐ_ｉ における装置の停止の結果として前記工程Ｐ_ｉ＋１ において不足することになる製品の個数に対応する安全仕掛かり数を確保する、生産ラインにおける安全仕掛かり数の確保方法であって、
装置Ｅ_ｊ の工程Ｐ_ｉ に対する処理能力をＴ_ｉｊ，装置Ｅ_ｊ の、工程Ｐ_ｉ に対する使用比率をＲ_ｉｊとして、工程Ｐ_ｉ の処理能力Ｔ_Ｒｉを
【００３２】
【数４０】

【００３３】
により求め、
工程Ｐ_i の基準処理能力をＴ_i として、工程Ｐ_i の装置台数Ｃ_EPi を
【００３４】
【数４１】

【００３５】
により求め、
生産計画上、工程Ｐ_i において１日当たり必要な処理数をＮ_i 、Ｕ_d を他責稼働率として、工程Ｐ_i の必要装置台数Ｃ_ENi を
【００３６】
【数４２】

【００３７】
により求め、
装置Ｅ_j がＯ_fj日停止した場合に前記次工程で不足する製品個数を
【００３８】
【数４３】

【００３９】
により求め、前記Ｓ_ｉｊのうちの最大のものＳ_ｉ （Ｓ_ｉ ＝Ｍａｘ（Ｓ_ｉｊ，ｊ＝１，２・・・ｎ）に従って確保することを特徴とする生産ラインにおける安全仕掛かり数の確保方法により、または
請求項９に記載したように、
工程Ｐ_ｉ を前記装置群Ｅ_ｊ （ｊ＝１，２・・・ｎ）が処理し、次工程Ｐ_ｉ＋１ を装置群Ｅ_ｋ （ｋ＝１，２・・・ｍ）が処理する生産ラインにおいて、前記工程Ｐ_ｉ と前記工程Ｐ_ｉ＋１ との間に安全仕掛かりを設定できない場合に、仮想工程Ｐ_{ｉ，ｉ＋１} と仮想装置Ｅ_ｊｋとを定義し、前記仮想工程Ｐ_{ｉ，ｉ＋１} に対して安全仕掛かり数を確保する、生産ラインにおける安全仕掛かり数の確保方法であって、
仮想装置Ｅ_ｊ，ｋ の前記仮想工程Ｐ_{ｉ，ｉ＋１} に対する処理能力をＴ_ｊｋ，仮想装置Ｅ_ｊｋの、前記仮想工程Ｐ_{ｉ，ｉ＋１} に対する使用比率をＲ_ｊ，ｋ として、前記仮想工程Ｐ_{ｉ，ｉ＋１} の処理能力Ｔ_{Ｒｉ，ｉ＋１}を
【００４０】
【数４４】

【００４１】
により求め、
前記仮想工程Ｐ_i+1 の基準処理能力をＴ_i,i+1 として、前記仮想工程Ｐ_i,i+1 の装置台数Ｃ_EPi,i+1 を
【００４２】
【数４５】

【００４３】
により求め、
生産計画上、前記仮想工程Ｐ_i,i+1 において１日当たり必要な処理数をＮ_i,i+1 、Ｕ_d を他責稼働率として、前記仮想工程Ｐ_i,i+1 の必要装置台数Ｃ_ENi,i+1 を
【００４４】
【数４６】

【００４５】
により求め、
装置Ｅ_j がＯ_f 日停止した場合に前記次工程で不足する製品個数Ｓ_j0を
【００４６】
【数４７】

【００４７】
により求め、
装置Ｅ_k がＯ_f 日停止した場合に前記次工程で不足する製品個数Ｓ_0kを
【００４８】
【数４８】

【００４９】
により求め、
前記安全仕掛かり数を、前記Ｓ_ｊ０とＳ_ｏｋのうちの最大のものＳ_{ｉ，ｉ＋１} （Ｓ_{ｉ，ｉ＋１} ＝Ｍａｘ（Ｓ_ｊｏ，Ｓ_ｏｋ））に従って確保することを特徴とする生産ラインにおける安全仕掛かり数の確保方法により、または
【００５１】
請求項１０に記載したように、
工程群Ｐ_ｉ （ｉ＝１，２・・・ｍ）を含み、前記工程群に製品を流すことにより、装置群Ｅ_ｊ （ｊ＝１，２・・・ｎ）を使って前記製品に対して必要な加工を行なう生産ラインであって、
一の工程Ｐ_ｉ と次の工程Ｐ_ｉ＋１ との間に、前記工程Ｐ_ｉ における装置の停止の結果として前記工程Ｐ_ｉ＋１ において不足することになる製品の個数に対応した安全仕掛かり数に等しい空き棚を備え、
前記一の工程Ｐ_ｉ の直前にも、前記安全仕掛かり数に等しい空き棚を備え、
前記安全仕掛かり数は、
装置Ｅ_ｊ の工程Ｐ_ｉ に対する処理能力をＴ_ｉｊ，装置Ｅ_ｊ の、工程Ｐ_ｉ に対する使用比率をＲ_ｉｊとして、工程Ｐ_ｉ の処理能力Ｔ_Ｒｉを
【００５２】
【数５０】

【００５３】
により求め、
工程Ｐ_i の基準処理能力をＴ_i として、工程Ｐ_i の装置台数Ｃ_EPi を
【００５４】
【数５１】

【００５５】
により求め、
生産計画上、工程Ｐ_i において１日当たり必要な処理数をＮ_i 、Ｕ_d を他責稼働率として、工程Ｐ_i の必要装置台数Ｃ_ENi を
【００５６】
【数５２】

【００５７】
により求め、
装置Ｅ_j がＯ_fj日停止した場合に前記次工程で不足する製品個数を
【００５８】
【数５３】

【００５９】
により求め、
前記安全仕掛かり数が、前記Ｓ_ｉｊのうちの最大のものＳ_ｉ （Ｓ_ｉ ＝Ｍａｘ（Ｓ_ｉｊ，ｊ＝１，２・・・ｎ）となるように設定されていることを特徴とする生産ラインにより、または
請求項１１に記載したように、
工程Ｐ_ｉ を前記装置群Ｅ_ｊ （ｊ＝１，２・・・ｎ）が処理し、次工程Ｐ_ｉ＋１ を装置群Ｅ_ｋ （ｋ＝１，２・・・ｍ）が処理し、その際前記工程Ｐ_ｉ と前記工程Ｐ_ｉ＋１ との間に安全仕掛かりを設定できない生産ラインであって、
前記工程Ｐ_ｉ＋１ と次の工程Ｐ_ｉ＋２ との間に、前記工程Ｐ_ｉ における装置の停止の結果として前記工程Ｐ_ｉ＋１ において不足することになる製品の個数に対応した安全仕掛かり数に等しい空き棚を備え、
前記一の工程Ｐ_ｉ の直前にも、前記安全仕掛かり数に等しい空き棚を備え、
前記安全仕掛かり数は、
仮想工程Ｐ_{ｉ，ｉ＋１} と仮想装置Ｅ_ｊｋとを定義し、前記仮想工程Ｐ_{ｉ，ｉ＋１} に対して、
仮想装置Ｅ_ｊ，ｋ の前記仮想工程Ｐ_{ｉ，ｉ＋１} に対する処理能力をＴ_ｊｋ，仮想装置Ｅ_ｊｋの、前記仮想工程Ｐ_{ｉ，ｉ＋１} に対する使用比率をＲ_ｊ，ｋ として、前記仮想工程Ｐ_{ｉ，ｉ＋１} の処理能力Ｔ_{Ｒｉ，ｉ＋１}を
【００６０】
【数５４】

【００６１】
により求め、
前記仮想工程Ｐ_i+1 の基準処理能力をＴ_i,i+1 として、前記仮想工程Ｐ_i,i+1 の装置台数Ｃ_EPi,i+1 を
【００６２】
【数５５】

【００６３】
により求め、
生産計画上、前記仮想工程Ｐ_i,i+1 において１日当たり必要な処理数をＮ_i,i+1 、Ｕ_d を他責稼働率として、前記仮想工程Ｐ_i,i+1 の必要装置台数Ｃ_ENi,i+1 を
【００６４】
【数５６】

【００６５】
により求め、
装置Ｅ_j がＯ_f 日停止した場合に前記次工程で不足する製品個数Ｓ_j0を
【００６６】
【数５７】

【００６７】
により求め、
装置Ｅ_k がＯ_f 日停止した場合に前記次工程で不足する製品個数Ｓ_0kを
【００６８】
【数５８】

【００６９】
により求め、前記Ｓ_ｊ０とＳ_ｏｋのうちの最大のものＳ_{ｉ，ｉ＋１} （Ｓ_{ｉ，ｉ＋１} ＝Ｍａｘ（Ｓ_ｊｏ，Ｓ_ｏｋ））に従って決定されていることを特徴とする生産ラインにより、解決する。
［作用］
本発明では、工程の直後に、その工程の装置の長時間にわたる停止の影響を他工程に及ぼさないための安全仕掛かり数に相当する仕掛かりを確保し、直前にはこれとほぼ同数の空き棚を確保しておく。そして、長時間停止が発生した場合には、直後仕掛かりが次工程で処理されて減少すると共に、直前にこれとほぼ同数の投入待ちの仕掛かりが溜まる。直後仕掛かりと直前仕掛かりの和が、平常時も装置長時間停止時にもおおよそ一定となるように生産ラインを管理することで、装置の長時間にわたる停止が他工程に影響するのが回避される。これに対し、従来は直前の仕掛かりのみを考慮していたため、装置が長時間にわたり停止した場合には、仕掛かりが増大してしまい、生産ラインが停止してしまう。これに対し、本発明では直前仕掛かりと直後仕掛かりの和について、計画数と実績数とを比較することで管理を行なうため、ラインを止める必要がなくなり、装置停止の影響を、装置停止が生じた工程のみにより吸収することが可能になる。
【００７０】
また、本発明は、装置の稼動実績データから安全仕掛かり数を計算する方法を提供する。この方法は、安全仕掛かり数を仕掛かり数と処理数の推移から近似的に求める方法に比べて、計画仕掛かり数を明確に定義することが可能である。本発明では、前記安全仕掛かり数を計算することにより、必要なストッカーの棚数を決定する。こうすることで、必要なところに必要な棚数が容易され、生産ライン中のある工程におけるある装置の停止が他の工程に及ぶのが回避され、生産ラインのスループットが向上する。しかも、本発明では無駄な棚が設けられることがなく、ストッカーのコストも最小化される。
【００７１】
【発明の実施の形態】
［第１実施例］
以下、本発明を液晶表示装置を構成するＴＦＴ基板の製造に適用した場合について、図１を参照しながら説明する。
図１を参照するに、ＴＦＴ基板の製造ラインは工程Ｐ₁ 〜Ｐ₉ を含み、装置Ｅ₁ 〜Ｅ₄ が工程Ｐ₂ ，Ｐ₅ ，Ｐ₈ を処理している。このうち、前記工程Ｐ₂ は装置Ｅ₁ とＥ₂ が処理し、一方工程Ｐ₅ では装置Ｅ₁ 〜Ｅ₄ の全てが使われている。図１中、工程Ｐ₁ ，Ｐ₄ ，Ｐ₇ は成膜工程に対応し、工程Ｐ₂ ，Ｐ₅ およびＰ₈ はフォト工程、またＰ₃ ，Ｐ₆ ，Ｐ₉ がエッチング工程に対応する。工程Ｐ₁ 〜Ｐ₉ まで順に処理を進めることにより、ＴＦＴ基板の処理がなされる。
【００７２】
本実施例では各工程の負荷率を求め、これを等しくするように各装置の使用比率を決めることにより、各工程の処理能力を定める。さらに、適正な計画仕掛かり数（安全仕掛かりと基本仕掛かり）を決めることにより、製造ラインの能力を最大化する。
最初に、各工程の処理能力Ｔ_Riを、工程Ｐ_i に対する装置Ｅ_j の使用比率をＲ_ijとし、装置Ｅ_j の処理能力をＴ_ijとして、以下のように求める。
【００７３】
Ｔ_R2＝Ｒ₂₁・Ｔ₂₁・Ｒ₂₂・Ｔ₂₂
Ｔ_R5＝Ｒ₅₁・Ｔ₅₁・Ｒ₅₂・Ｔ₅₂・Ｒ₅₃・Ｔ₅₃・Ｒ₅₄・Ｔ₅₄
Ｔ_R8＝Ｒ₈₃・Ｔ₈₃・Ｒ₈₁・Ｔ₈₁
さらに、各工程Ｐ_i の負荷率をＬ_i ，他責稼働率をＵｄとして、必要な基板処理枚数Ｎ_i を、
Ｎ_i ［枚／日］＝［工程Ｐ_i での生産計画上必要処理枚数］／［月の操業日数］で定義すると、各工程の負荷率Ｌ_i は次式で計算できる。
【００７４】
Ｌ₂ ＝Ｎ₂ ／［Ｔ_R2×Ｕ_d2／１００］
Ｌ₅ ＝Ｎ₅ ／［Ｔ_R5×Ｕ_d5／１００］
Ｌ₈ ＝Ｎ₈ ／［Ｔ_R8×Ｕ_d8／１００］
ここで、Ｌ₂ ＝Ｌ₅ ＝Ｌ₈ となるように、換言すると各工程の負荷率が平準化するように装置Ｅ_ijの使用比率Ｒ₂₁，Ｒ₂₂，Ｒ₅₁，Ｒ₅₂，Ｒ₅₃，Ｒ₅₄，Ｒ₈₃，Ｒ₈₁を定める。これにより、製造ラインのスループットを最大化する最適な装置の使用比率が求められる。
【００７５】
ここで、工程Ｐ_i の基準処理能力Ｔ_i ［枚／日］を、
Ｔ_i ＝Ｍａｘ（Ｔ_ij，ｊ＝１，・・・ｍ）とし、
工程Ｐ_i の装置台数Ｃ_EPi を
【００７６】
【数５９】

【００７７】
で定義し、さらに工程Ｐ_i の必要装置台数を、
Ｃ_ENi ＝Ｎ_i ・（Ｔ_i ・Ｕ_d ／１００） ［台］
で定義する。
すると、装置Ｅ_ijが期間Ｏ_fj［日］停止した場合に次工程で不足する基板数Ｓ_ij、換言すると前工程で溜まる基板数Ｓ_ijは、
【００７８】
【数６０】

【００７９】
で計算できる。ただし、期間Ｏ_fjは生産計画上、生産量の管理期間（通常１ヵ月程度）内で予想される最長の装置停止時間である。
このようにして求まったｊ＝１，２・・・ｎの各装置に対する基板数Ｓ_ijのうち、最も数量の大きいものＳ_i 、すなわちＳ_i ＝Ｍａｘ（Ｓ_ij，ｊ＝１，２・・・ｎ）を、工程Ｐ_i の安全仕掛かり数とする。
【００８０】
そして、前記工程Ｐ_i の直後に、前記安全仕掛かり数Ｓ_i あるいはこれに最も近いロット編成基板数の総和を表す整数に対応した仕掛かりを確保するように、前記製造ラインを管理する。また、前記工程Ｐ_i の直前に、前記工程Ｐ_i の歩留まりをＢ_i として、Ｓ_i ／Ｂ_i ×１００に対応した、あるいはこれに最も近いロット編成基板数の総和を表す整数に対応した空き棚を確保する。
【００８１】
かかる製造ラインの管理の結果、前記工程Ｐ_i における装置の停止の影響が他の工程に及ぶのが回避され、製造スループットが最大化される。
［第２実施例］
次に、仕掛りが溜まり易い制約工程であるＰ_s 工程とＰ_n 工程を例として、安全仕掛り数、装置停止時と回復後の仕掛り数の管理方法を、本発明の第２実施例として説明する。
【００８２】
Ｐ_s 工程とＰ_n 工程の間は、工程間で時間制約が厳しいため、インライン的取り扱いが必要であるものとする。Ｐ_s 工程と、Ｐ_n 工程の各装置の処理能力を表１に示す。
【００８３】
【表１】

【００８４】
まず、最長計画外オフライン時間を計算する。その際、ＭＴＢＦは信頼度９０％の係数により補正し、
Ｏｆ（Ｅ₀₁、計画外）＝2701n [1440 ×30／（14118 ×0.634)］＝425[min]
Ｏｆ（Ｅ₀₂、計画外）＝1801n [1440 ×30／（9792×0.675)］＝338[min]
Ｏｆ（Ｅ₁₀、計画外）＝6901n [1440 ×30／(25260×0.539)］＝797[min]を得る。
【００８５】
このうち、表１の最長計画はオフライン時間と比較して長い方を、各装置の最長停止時間とする。
Ｐ_s 工程はＥ₁₀１台で、Ｐ_n 工程はＥ₀₁とＥ₀₂の２台で処理を行う。Ｐ_s 工程の処理終了からＰ_n 工程の装置にロードする迄のプロセス的な猶予時間を４０［ｍｉｎ] 以内とすると、両工程間に安全仕掛りを置くことはできない。したがって、Ｅ₀₁とＥ₀₂はＥ₁₀と連続した仮想の装置として能力を計算する必要がある。
【００８６】
装置Ｅ₁₀と装置Ｅ₀₁を連続した仮想の装置をＥ₁₁、そのスループットをＴ₁₁［枚／日］、故障率をＦ₁₁とする。装置Ｅ₁₀と装置Ｅ₀₂を連続した仮想の装置をＥ₁₂、そのスループットをＴ₁₂［枚／日］、故障率をＦ₁₂で表わす。連続稼動時のＥ₁₀のスループットがＥ₀₁とＥ₀₂のスループットの和より大きいので、連続稼動時のＥ₁₁、Ｅ₁₂のタクトは、Ｅ₀₁とＥ₀₂のタクトに等しくなる。装置Ｅ₁₁の非故障率（１−Ｆ₁₁）は、各装置（Ｅ₁₀とＥ₀₁）の非故障率の積（１−Ｆ₁₀）・（１−Ｆ₀₁）で与えられる。また付帯作業時間は各装置の付帯作業時間を加えたものから、同時に行う付帯作業時間を差引いたものになると考えて、Ｔ₁₁、Ｔ₁₂は次式で計算することができる（付帯作業は独立に行うと仮定する）。
【００８７】

工程についても工程Ｐ_s と工程Ｐ_n を連続した仮想の工程Ｐ_snを考える。この工程に対する仮想装置Ｅ₁₁とＥ₁₂の使用比率Ｒ₁₁とＲ₁₂はいずれも１である。仮想工程Ｐ_snの処理能力をＴ_R,sn 、装置台数をＣ_EP,sn 、必用装置台数をＣ_EN,sn 、負荷率をＬ_snとする。
【００８８】

工程Ｐ_snの装置台数Ｃ_EP,sn は、基準処理能力をＴ_snとすると、

月当りの必用処理数を27000 ［枚／日］、月の操業日数を３０日、工程他責稼動率Ｕｄを９０％とすると、仮想の工程Ｐ_snで１日当り必用な処理枚数Ｎ_snは900 ［枚／日］となり、

装置Ｅ₁₀、Ｅ₀₁、Ｅ₀₂の各装置停止時について仮想工程Ｐ_snに対して安全仕掛りを試算する。実際には、Ｐ_n 工程の直後に安全仕掛り数Ｓ_s に相当する仕掛りを置き、Ｐ_s とＰ_n の両工程に対する安全仕掛りと考える
［Ｅ₁₀停止時］安全仕掛りＳ₁₀は

以上の結果により、Ｅ₀₂の停止は影響しないがＥ₀₁とＥ₁₀の停止の影響が同程度であり、安全仕掛りは５２３［枚］、約２６［ロット］必要であることがわかる。すなわちＰ_n 工程直後に２６［ロット］の仕掛りが、またＰ_s 工程直前に２６棚の空き棚が必要である。
［第３実施例］
次に基本仕掛り計算の一実施例を実施例１の仮想工程Ｐ_snについて示す。表２に計算のため、各装置の基礎データを示す。
【００８９】
また表３に仮想装置Ｅ₁₁、Ｅ₁₂と仮想工程Ｐ_snの基本仕掛りの計算結果を示す。
【００９０】
【表２】

【００９１】
【表３】

【００９２】
仮想装置については、２台の連続した装置のうち入口側装置Ｅ₁₀の処理待ち仕掛りＳ_W,10、搬送待ち仕掛りＳ_T,10を、仮想装置Ｅ₁₁（Ｅ₁₂）のＳ_W,11（Ｓ_W,12）、Ｓ_T,11（Ｓ_T,12）とする。出口側装置Ｅ₀₁（Ｅ₀₂）の搬出待ち仕掛りＳ_F,01（Ｓ_F,02）を、仮想装置Ｅ₁₁（Ｅ₁₂）のＳ_F,11（Ｓ_F,12）とする。また、入口側装置Ｅ₁₀の処理中仕掛りＳ_P,10、搬出待ち仕掛りＳ_F,10と出口側装置Ｅ₀₁（Ｅ₀₂）の処理待ち仕掛りＳ_W,01（Ｓ_W,02）、処理中仕掛りＳ_P,01（Ｓ_P,02）を加えたものを仮想装置のＳ_P,11（Ｓ_P,12）とした。
【００９３】
仮想工程Ｐ_snについては、仮想装置Ｅ₁₁、Ｅ₁₂の入口側装置Ｅ₁₀が共通であるため、Ｅ₁₁、Ｅ₁₂の各仕掛り数（処理中、処理待ち、搬出待ち、搬送待ち）の和から、Ｅ₁₁とＥ₁₂で共通の仕掛り数を引いたものをＰ_snの各仕掛り数（処理中、処理待ち、搬出待ち、搬送待ち）とした。
Ｐ_snの必要稼動率Ｕ_snは、工程他責稼動率９０％として、
Ｕ_sn＝90・Ｃ_EN,sn ／Ｃ_EP,sn ＝90・1.079/1219=79.66 ［％］（４）
全体としての非故障率（１−Ｆ_sn）は、仮想装置Ｅ₁₁とＥ₁₂の非故障率の平均を取る。
【００９４】
（１−Ｆ_sn）＝（0.981 ×0.973+0.982 ×0.973)/2=0.955
したがって、仮想工程Ｐ_snの基本仕掛りＳ_K,snは次式で計算できる。
Ｓ_K,sn＝0.7966×(7+1+2+1) ×0.955=11×0.7608=8.4［ロット］ （５）
［第４実施例］
次に工程の基本日程を安全仕掛りと基本仕掛りから計算する一実施例を実施例２、３の場合について示す。Ｐ_s 工程とＰ_n 工程を合せた仮想工程の仕掛りは、基本仕掛りが８．４［ロット］、安全仕掛りが２６［ロット］であることがわかる。１日当り必要な処理ロット数は、９００［枚／日］を２０［枚／ロット］で割って、４５［ロット／日］であるから、基準日程Ｋ_snは次式で計算できる。
【００９５】
Ｋ_sn＝8.4/45+26/45=0.1867+0.5778=0.7644 ［日］
Ｐ_s 工程とＰ_n 工程に前記の安全仕掛りを置き、基準日程０．７６４４［日］で日程管理を行うことにより、装置の長時間停止の影響が他工程に及ぶのを防止できる。
［第５実施例］
次に安全仕掛りと基本仕掛りを基に実際の後工程引きでの日程管理を行う方法について、本発明の第５実施例として、図２を参照しながら説明する。
【００９６】
図２は、Ｐ_sn工程前後の計画仕掛りを示す。Ｐ_sn工程の基本仕掛りＳ_K,snは、搬送待ち、処理待ち、処理中、搬出待ちの各仕掛りの和Ｓ_T,sn＋Ｓ_W,sn＋Ｓ_P,sn＋Ｓ_F,snに等しい。Ｐ_sn工程の基準日程は、この基本仕掛りに対応する日程と、安全仕掛りに対応する日程の和で与えられる。各ロットのステータスが、（…→［前工程基本仕掛り］）→［前工程安全仕掛り］→［Ｐ_sn工程基本仕掛り］→［Ｐ_sn工程安全仕掛り］→［後工程基本仕掛り］→［後工程安全仕掛り］→…）と順次移ることにより工程が進捗する。
【００９７】
図３に現状の工程管理システム上で実際に監視（収集）できる実績仕掛りを示す。収集できる実績仕掛りは、工程管理システム上の各工程（オペレーション）の処理中仕掛りと、処理待ち仕掛りである。これらの処理中・処理待ち仕掛りから、図２の基本仕掛り・安全仕掛りに対応する実績仕掛りを計算できる。
Ｐ_sn工程の基本仕掛り数Ｓ_K,snに対応する実績仕掛り、Ｓ_Z,snは、｛Ｐ_s 工程処理中仕掛りＳ_Z,s11 ）＋（Ｐ_n 工程処理待ち仕掛りＳ_Z,n+0 ）＋（Ｐ_n 工程処理中仕掛りＳ_Z,n+1 ）＋１｝で計算できる。Ｓ_Z,snが基本仕掛り数Ｓ_K,snと一致するように日程管理を行う。１を足すのは、実績値Ｓ_Z,snにＰ_sn工程の搬送待ち仕掛りＳ_T,snが含まれないためである。Ｓ_Z,snを工程Ｐ_snの処理中仕掛りと呼ぶ。
【００９８】
Ｐ_sn工程の安全仕掛り数Ｓ_snに対応する仕掛り、Ｓ_Z,sna は、｛（前工程処理待ち仕掛りＳ_Z,as0 ）−１｝で計算できる。Ｓ_Z,sna を工程Ｐ_snの直後仕掛りと呼ぶ。
Ｐ_s 工程の前工程Ｐ_srの安全仕掛りＳ_srに対応する実績仕掛り、Ｓ_Z,sra は、｛（Ｐ_s 工程処理待ち仕掛りＳ_Z,s10 ）−１｝である。Ｓ_Z,sra を工程Ｐ_srの直後仕掛りと呼ぶ。
【００９９】
（Ｓ_sn−Ｓ_Z,sna ）≧２０になったら（Ｐ_sn工程の直後仕掛りＳ_Z,sna に、安全仕掛りＳ_snに対して、１［ロット］分の空きができたら）、Ｐ_sn工程の処理中仕掛りＳ_Z,snから１［ロット］を進めて、Ｐ_sn工程の直後仕掛りＳ_Z,sna に入れる。
同様に（Ｓ_K,sn−Ｓ_Z,sn）≧２０になったら（Ｐ_sn工程の処理中仕掛りＳ_Z,snに、基本仕掛りＳ_K,snに対して、１［ロット］以上の空きができたら）Ｐ_sr工程の直後仕掛りＳ_Z,sra から１［ロット］をＰ_sn（スライトエッチ）工程に進めて、Ｐ_sn工程の処理中仕掛りＳ_Z,snに入れる。
【０１００】
一般に工程Ｐ_i の安全仕掛り（計画）Ｓ_i と工程Ｐ_i の直後仕掛り（実績）Ｓ_Z,ia、工程Ｐ_i の基本仕掛り（計画）Ｓ_K,i と処理中仕掛り（実績）Ｓ_Z,i を順次比較して、実績仕掛りに計画仕掛りに対する１［ロット］分の空きがてきたことを確認して、ロットのステータスを［Ｐ_i-1 ］工程の直後仕掛り→Ｐ_i 工程の処理中仕掛り、Ｐ_i 工程の処理中仕掛り→Ｐ_i 工程の直後仕掛りというように順次移して進捗させていく。これにより後工程引きでのロット進捗が可能となる。
［第６実施例］
次に、Ｐ_sn工程を例として、装置で長時間停止が実際に生じた場合の日程管理方法を説明する。Ｅ₁₀装置で８００［ｍｉｎ］の故障停止が発生したと仮定する。
【０１０１】
図４にＰ_sn工程前後の計画仕掛り（安全仕掛りと基本仕掛り）と空き棚を示す。空き棚は装置の長時間停止時に工程直前に溜まるロットを収納するためのもので、安全仕掛り数をロットの基本編成の数２０で割ったものに等しい。また、図５に、装置長時間停止時のＰ_sn工程前後の実績仕掛りの様子を示す。
Ｅ₁₀装置停止中は、Ｐ_sn工程の処理が停止する。Ｐ_sn工程以外の工程は計画通り処理を行う。Ｐ_sn工程の後工程の処理中仕掛りＳ_Z,asに基本仕掛りＳ_K,asに対する空きができる毎に、Ｐ_sn工程の直後仕掛りＳ_Z,sna のロットのステータスがＳ_Z,asに移る。
【０１０２】
一方、Ｐ_snの工程の処理中仕掛りＳ_Z,snのうち搬送待ちと処理待ちの２［ロット］は、装置停止中はステータスが変らない。残りの処理中と搬出待ちの９ロットのステータスはＰ_sn工程の直後仕掛りＳ_Z,sna に順次移る。したがって、Ｐ_sn工程の処理中仕掛りＳ_Z,snは２［ロット］となる。これ以降は処理中仕掛りＳ_Z,snから直後仕掛りＳ_Z,sna への補充ができないため、Ｓ_Z,sna が減少していく。
【０１０３】
Ｐ_sn工程の直前には、安全仕掛り数に等しい空き棚が用意されている。装置長時間停止中は、この空き棚に、前工程Ｐ_srの直後仕掛りＳ_Z,sna からロットを移す。空き棚に収納される仕掛りを、Ｐ_sn工程の直前仕掛りと呼び、Ｓ_Z,snb で表わす。
Ｐ_sn工程の直後仕掛りＳ_Z,snb がＰ_sn工程の安全仕掛り数Ｓ_snに等しくなるまで、Ｓ_Z,sra からＳ_Z,snb にロットのステータスを移していく。移すタイミングは、Ｐ_sn工程の後工程の処理中仕掛りＳ_Z,asに基本仕掛りＳ_K,asに対する空きができるタイミングで、Ｐ_sn工程の直後仕掛りＳ_Z,sna のロットのステータスをＳ_Z,asに移すのと、同じタイミングで移せば良い。これによって、Ｐ_sn工程停止の影響を受けずにライン全体としては後工程引きで生産を続けることができる。
【０１０４】
ただし、Ｓ_Z,snb ≧Ｓ_snとなったら（直前仕掛りの数が安全仕掛り数を越えたら）、ライン全体を止める。実際にはＳ_snを予測される最長停止時間に合せて設定しているので、ライン全体の停止は原則として起こらない筈である。
８００［ｍｉｎ］後にＥ₁₀装置が復旧する迄に、Ｐ_sn工程の直後仕掛りと処理中仕掛りの和、〔Ｓ_Z,sna ＋Ｓ_Z,sn〕は５００［枚］、２５［ロット］分減少する。実際には直後仕掛りＳ_Z,sna が１６［ロット］減少して１０［ロット］になり、Ｐ_sn工程の処理中仕掛りＳ_Z,snが９［ロット］減少して２［ロット］になっている。そして、Ｐ_sn工程の直前仕掛りＳ_Z,snb が０［ロット］から２５［ロット］に増加している。
［第７実施例］
先の長時間装置停止復旧後に減少した仕掛を安全仕掛り数まで回復させる方法についての実施例を示す。実施例６でＶ₆ 、Ｅ₁₀装置復旧後は、Ｐ_sn工程の稼動率を平常より高くして、必要な仕掛り数を回復する必要がある。即ち、Ｐ_sn工程の直前仕掛りＳ_Z,snb の２５［ロット］のステータスを、処理中仕掛りＳ_Z,snを経て、直後仕掛りＳ_Z,sna に移せば良い。当然、ライン全体の稼動を維持するのに必要な９００［枚／日］を処理した余力を向けることになる。
【０１０５】
ここでは、Ｐ_sn工程の稼動率を１００％に上げた場合の回復時間を計算する。Ｐ_sn工程の必要稼動率は、（４）式より８０％であり、振り向けることができる余力は２０％である。回復すべき仕掛り数は５００［枚］、Ｐ_sn工程の基準処理能力は（１）式よりＴ_sn＝９２７［枚／日］、装置台数は（２）式よりＣ_EP,sn ＝1.219 ［台］であるから、
Ｋ＝500/｛1.219 ・927(1-80/100) ｝＝2.21 ［日］（６）
したがって、約２．２［日］でＰ_sn工程の直後仕掛りＳ_Z,sna の数を、安全仕掛り数５２３［枚］迄回復させることができる。
【０１０６】
以上、本発明を好ましい実施例について説明したが、本発明は上記の実施例に限定されるものではなく、特許請求の範囲に記載の要旨内において様々な変形・変更が可能である。
【０１０７】
【発明の効果】
請求項１〜２１記載の本発明の特徴によれば、工程の直後に、その工程の装置の長時間にわたる停止の影響を他工程に及ぼさないための安全仕掛かり数に相当する仕掛かりを確保し、直前にはこれとほぼ同数の空き棚を確保しておく。こうしておくことにより、長時間にわたる装置の停止が発生した場合には、直後仕掛かりが次工程で処理されて減少すると共に、直前にこれとほぼ同数の投入待ちの仕掛かりが溜まる。その際、直後仕掛かりと直前仕掛かりの和が、平常時も装置長時間停止時にもおおよそ一定となるように生産ラインを管理することで、装置の長時間にわたる停止が他工程に影響するのが回避される。すなわち、本発明では直前仕掛かりと直後仕掛かりの和について、計画数と実績数とを比較することで管理を行なうため、ラインを止める必要がなくなり、装置停止の影響を、装置停止が生じた工程のみにより吸収することが可能になる。
【０１０８】
また、本発明は、装置の稼動実績データから安全仕掛かり数を計算する方法を提供する。この方法は、安全仕掛かり数を仕掛かり数と処理数の推移から近似的に求める方法に比べて、計画仕掛かり数を明確に定義することが可能である。本発明では、前記安全仕掛かり数を計算することにより、必要なストッカーの棚数を決定する。こうすることで、必要なところに必要な棚数が容易され、生産ライン中のある工程におけるある装置の停止が他の工程に及ぶのが回避され、生産ラインのスループットが向上する。しかも、本発明では無駄な棚が設けられることがなく、ストッカーのコストも最小化される。
【図面の簡単な説明】
【図１】本発明の第１実施例による生産管理方法を説明する図である。
【図２】本発明の第５実施例による生産管理方法を説明する図（その１）である。
【図３】本発明の第５実施例による生産管理方法を説明する図（その２）である。
【図４】本発明の第６実施例による生産管理方法を説明する図（その１）である。
【図５】本発明の第６実施例による生産管理方法を説明する図（その２）である。
【符号の説明】
Ｐ₁ 〜Ｐ₈ 工程[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a production management method in a production line for a liquid crystal glass substrate, a PDP substrate, or a semiconductor wafer. The present invention also relates to a method for designing a production line for such a liquid crystal glass substrate, a PDP substrate, or a semiconductor wafer.
[0002]
[Prior art]
Conventionally, in the production line of semiconductor devices, the target in-process number of its own process is determined in advance, and the amount of deviation between this and the current in-process number of its own process is calculated. Japanese Laid-Open Patent Publication No. 7-74226 proposes a method for leveling the number of in-process processes by stopping the process in step S2 and reserving the process in the previous process if there is less.
[0003]
In each process, a method has been proposed in which the number of work in progress for the required number of processed sheets is obtained from a regression line or approximate curve from data on the number of work in progress and the number of processes.
Furthermore, Nikkei Microdevices, March 1998, pp104-107, describes a production management method that assumes that all equipment is stopped and the equipment is repaired when the equipment is shut down, and that there is no work in progress for safety. .
[0004]
Conventionally, when designing and configuring a production line for semiconductor devices, the number of storage shelves provided in each bay stocker is determined from the production plan. There is known a method for determining the sum of the total number (“from”) and the total number of shipments to the interbay transportation (“to”) as a guide. The guideline may be the total for one day, depending on the turnover rate required by the factory (total number of work in each bay / total number of lots processed in that bay per day) It may be the total number. In any case, the number of stocker shelves is determined according to the ratio of the total number of “from” and “to” of each stocker.
[0005]
On the other hand, a method has been proposed in which a device is distributed and stored near the device without placing a stocker for each bay (Nikkei Microdevices, supra).
[0006]
[Problems to be solved by the invention]
However, in the method described in Japanese Patent Laid-Open No. 7-74226, production is performed smoothly, and in a production line in which a scheduled work-in-process is secured in each process, an apparatus having a certain process is long due to a failure. If the process is stopped for a while, the in-process will not decrease at all in the process where the failure has occurred. On the other hand, if processing continues in the upstream process, the in-process will exceed the target in-process number. Will increase. In such a case, it is necessary to stop all the upstream processes. In addition, the whole process on the downstream side is stopped due to zero work in progress. In addition, when production management of such a configuration is performed, when the faulty device is restored, it is necessary to increase the operating rate of the processing device in all processes, but the required operating rate is temporarily included in it. If processes that cannot be achieved are involved, production delays can never be recovered.
[0007]
On the other hand, in the method of obtaining the number of work in progress for the required number of processing from the data of the past number of work in progress and the number of processes from the regression line or approximate curve, if the processing equipment stops for a long time, the effect of the stop is It is inevitable that it extends to the entire production line. The number of work in progress with respect to the required number of processed sheets is, at most, the total of the work in progress of the device in the process, the work in progress, and the work in progress waiting to the processing wait position. The number of work in progress easily exceeds the number of work in progress set in this way.
[0008]
In addition, in the production management method in which all the lines are stopped when one process in the production line is stopped, all the lines are stopped for the time obtained by adding all the stop times of the apparatuses. Unless the downtime is improved significantly, the throughput of the production line is not improved.
Particularly in a production line for producing an ultra-large liquid crystal substrate and a production line for producing a semiconductor wafer having a diameter of 300 mm or more, the amount of investment is enormous, and it is difficult to provide a large number of spare devices in each process. For this reason, the stop of one apparatus often stops the process of one process completely, or the capacity of the entire production line is halved. In addition, the production line for such an ultra-large liquid crystal substrate becomes large-scale, and the amount of work at the time of a failure or periodic inspection increases. Once stopped, it often takes a very long time to recover.
[0009]
As described above, in a production line for an ultra-large liquid crystal substrate or the like, it is difficult to ensure the operation rate of the apparatus or process, and the stoppage of the apparatus for a long time has a serious impact on the manufacturing cost.
SUMMARY OF THE INVENTION Accordingly, it is a general object of the present invention to provide a new and useful production management method and production line design method that solve the above problems.
[0010]
A more specific object of the present invention is to provide a production management method in which the influence of a failure occurring in an apparatus in a certain process does not affect other processes in a production line composed of a plurality of processes.
Another object of the present invention is that when designing a production line, the number of stocker shelves used to hold work-in-process in a certain device in the production line is calculated based on the actual performance of the device. An object of the present invention is to provide a production line design method that is determined based on the number of hooks.
[0011]
[Means for Solving the Problems]
  The present invention solves the above problems.
  As described in claim 1,
  CraftGroup P_i (I = 1, 2,...), And the product group E by flowing the product through the process group_j (J = 1, 2... N) is a production management method for a production line that performs necessary processing on the product,
  One process P_i And next process P_{i + 1} And the process P_i As a result of the shutdown of the device in step P_{i + 1} The number of in-process safety devices corresponding to the number of products
  Device E_j Process P of_i Processing capacity for T_ij, Device E_j Process P_i Use ratio to R_ijAs process P_i Processing capacity T_RiThe
[0012]
[30]

[0013]
Sought by
Process P_iStandard processing capacity of T_iAs process P_iNumber of devices C_EPiThe
[0014]
[31]

[0015]
Sought by
Process P in production plan_iThe number of processing required per day in N_i, U_dAs the other responsible operation rate, process P_iNecessary equipment number C_ENiThe
[0016]
[Expression 32]

[0017]
Sought by
Device E_jIs O_fjIf the number of products is insufficient in the next process
[0018]
[Expression 33]

[0019]
And the above S_ijThe largest of them S_i (S_i = Max (S_ij, J = 1, 2,... N),
  Further, the process P_i Immediately before_i A production management method characterized by securing a number of empty shelves corresponding to
  Claim2As described in
  The number of the empty shelves is equal to the process P._i Y yield_i As 100S_i / B_i Claims determined according to1According to the production control method described or
  Claim3As described in
  Usage ratio R of the device_jiIs the process P_i Required processing capacity T_RiWithin the range that satisfies the above, the number of safety work in progress S_i Is determined to minimize1 or 2According to the production control method described or
  Claim4As described in
  The stop period O_fjSEMI E10-96
The longer of the planned offline time and the unplanned offline time specified in the standard.1 or 2According to the production control method described or
  Claim5As described in
  The stop period O_fjIs the average failure interval defined in the SEMI E10-96 standard, based on the average unscheduled offline time MTUO, the average unplanned downtime interval MTUD, and the production control period P days in the production plan. As the lower limit of the reliability of
      O_fj(Sun) = MTUO · ln {P / (k · MTUD)}
Claims sought by1 or 2According to the production control method described or
  Claim6As described in
  Each process P _i In apparatus E _j Regarding the use of Step P _i In the case where restrictions are imposed by the type of product processed in the above process group P _i Instead of (i = 1, 2,..., M), the process type group P is obtained by subdividing the process group according to the type of product. _i (I = 1, 2,... Z), and the process type group P _i The production management method according to claim 1, further comprising: calculating the safety work in progress and the basic work in progress for each of the process varieties included in Or
  As described in claim 7,
  Process P_i The device group E_j (J = 1, 2,... N) processed and the next process P_{i + 1} Device group E_k (K = 1, 2,..., M) is a production management method in a production line processed, and the process P_i And the process P_{i + 1} Virtual process P when safety device cannot be set between_{i, i + 1} And virtual device E_jkAnd the virtual process P_{i, i + 1} The number of safe work in progress
  Virtual device E_{j, k} The virtual process P_{i, i + 1} Processing capacity for T_jk, Virtual device E_jkOf the virtual process P_{i, i + 1} Use ratio to R_{j, k} As said virtual process P_{i, i + 1} Processing capacity T_{Ri, i + 1}The
[0020]
[Expression 34]

[0021]
Sought by
The virtual process P_{i + 1}Standard processing capacity of T_{i, i + 1}As said virtual process P_{i, i + 1}Number of devices C_{EPi, i + 1}The
[0022]
[Expression 35]

[0023]
Sought by
In the production plan, the virtual process P_{i, i + 1}The number of processing required per day in N_{i, i + 1}, U_dAs the other responsible operation rate, the virtual process P_{i, i + 1}Necessary equipment number C_{ENi, i + 1}The
[0024]
[Expression 36]

[0025]
Sought by
Device E_jIs O_fThe number of products S that is insufficient in the next process when the day is stopped_j0The
[0026]
[Expression 37]

[0027]
Sought by
Device E_kIs O_fThe number of products S that is insufficient in the next process when the day is stopped_0kThe
[0028]
[Formula 38]

[0029]
And the above S_j0And S_okThe largest of them S_{i, i + 1} (S_{i, i + 1} = Max (S_jo, S_ok)) Secure according to
  Further, the process P_i Immediately before_{i, i + 1} A production management method characterized by securing a number of empty shelves corresponding to
Or
  As described in claim 8,
[0031]
  CraftGroup P_i (I = 1, 2,...), And the product group E by flowing the product through the process group_j A production line that performs the necessary processing on the product using (j = 1, 2,... N)InOne process P_i And next process P_{i + 1} And the process P_i As a result of the shutdown of the device in step P_{i + 1} The number of safety devices that correspond to the number of products that will be insufficient inTo secure the number of safe work in progress on the production line.,
  Device E_j Process P of_i Processing capacity for T_ij, Device E_j Process P_i Use ratio to R_ijAs process P_i Processing capacity T_RiThe
[0032]
[Formula 40]

[0033]
Sought by
Process P_iStandard processing capacity of T_iAs process P_iNumber of devices C_EPiThe
[0034]
[Expression 41]

[0035]
Sought by
Process P in production plan_iThe number of processing required per day in N_i, U_dAs the other responsible operation rate, process P_iNecessary equipment number C_ENiThe
[0036]
[Expression 42]

[0037]
Sought by
Device E_jIs O_fjIf the number of products is insufficient in the next process
[0038]
[Expression 43]

[0039]
And the above S_ijThe largest of them S_i (S_i = Max (S_ij, J = 1, 2,... N)To secure the number of safe work in progressOr
  Claim9As described in
  Process P_i The device group E_j (J = 1, 2,... N) processed and the next process P_{i + 1} Device group E_k Production line processed by (k = 1, 2, ... m)In, The process P_i And the process P_{i + 1} Virtual process P when safety device cannot be set between_{i, i + 1} And virtual device E_jkAnd the virtual process P_{i, i + 1} The number of safe work in progressTo secure the number of safe work in progress on the production line.,
  Virtual device E_{j, k} The virtual process P_{i, i + 1} Processing capacity for T_jk, Virtual device E_jkOf the virtual process P_{i, i + 1} Use ratio to R_{j, k} As said virtual process P_{i, i + 1} Processing capacity T_{Ri, i + 1}The
[0040]
(44)

[0041]
Sought by
The virtual process P_{i + 1}Standard processing capacity of T_{i, i + 1}As said virtual process P_{i, i + 1}Number of devices C_{EPi, i + 1}The
[0042]
[Equation 45]

[0043]
Sought by
In the production plan, the virtual process P_{i, i + 1}The number of processing required per day in N_{i, i + 1}, U_dAs the other responsible operation rate, the virtual process P_{i, i + 1}Necessary equipment number C_{ENi, i + 1}The
[0044]
[Equation 46]

[0045]
Sought by
Device E_jIs O_fThe number of products S that is insufficient in the next process when the day is stopped_j0The
[0046]
[Equation 47]

[0047]
Sought by
Device E_kIs O_fThe number of products S that is insufficient in the next process when the day is stopped_0kThe
[0048]
[Formula 48]

[0049]
Sought by
  SaidThe number of safe work in progressS_j0And S_okThe largest of them S_{i, i + 1} (S_{i, i + 1} = Max (S_jo, S_ok)) Production line characterized by securing according toTo secure the number of safe work in progressAnd againIs
[0051]
  ContractClaim10As described in
  Process group P_i (I = 1, 2,...), And the product group E by flowing the product through the process group_j (J = 1, 2,... N) is a production line that performs the necessary processing on the product,
  One process P_i And next process P_{i + 1} And the process P_i As a result of the shutdown of the device in step P_{i + 1} Equipped with empty shelves equal to the number of work in progress corresponding to the number of products that will be insufficient in
  Said one process P_i Immediately before, equipped with empty shelves equal to the number of safe work in progress,
  The number of safe work in progress is
  Device E_j Process P of_i Processing capacity for T_ij, Device E_j Process P_i Use ratio to R_ijAs process P_i Processing capacity T_RiThe
[0052]
[Equation 50]

[0053]
Sought by
Process P_iStandard processing capacity of T_iAs process P_iNumber of devices C_EPiThe
[0054]
[Equation 51]

[0055]
Sought by
Process P in production plan_iThe number of processing required per day in N_i, U_dAs the other responsible operation rate, process P_iNecessary equipment number C_ENiThe
[0056]
[Formula 52]

[0057]
Sought by
Device E_jIs O_fjIf the number of products is insufficient in the next process
[0058]
[Equation 53]

[0059]
Sought by
  The number of safe work in progress isS_ijThe largest of them S_i (S_i = Max (S_ij, J = 1, 2... N), or by a production line characterized by
  Claim11As described in
  Process P_i The device group E_j (J = 1, 2,... N) processed and the next process P_{i + 1} Device group E_k (K = 1, 2,... M), in which case the process P_i And the process P_{i + 1} A production line that cannot set a safety device between
  Step P_{i + 1} And next process P_{i + 2} And the process P_i As a result of the shutdown of the device in step P_{i + 1} Equipped with empty shelves equal to the number of work in progress corresponding to the number of products that will be insufficient in
  Said one process P_i Immediately before, equipped with empty shelves equal to the number of safe work in progress,
  The number of safe work in progress is
  Virtual process P_{i, i + 1} And virtual device E_jkAnd the virtual process P_{i, i + 1} Against
  Virtual device E_{j, k} The virtual process P_{i, i + 1} Processing capacity for T_jk, Virtual device E_jkOf the virtual process P_{i, i + 1} Use ratio to R_{j, k} As said virtual process P_{i, i + 1} Processing capacity T_{Ri, i + 1}The
[0060]
[Formula 54]

[0061]
Sought by
The virtual process P_{i + 1}Standard processing capacity of T_{i, i + 1}As said virtual process P_{i, i + 1}Number of devices C_{EPi, i + 1}The
[0062]
[Expression 55]

[0063]
Sought by
In the production plan, the virtual process P_{i, i + 1}The number of processing required per day in N_{i, i + 1}, U_dAs the other responsible operation rate, the virtual process P_{i, i + 1}Necessary equipment number C_{ENi, i + 1}The
[0064]
[56]

[0065]
Sought by
Device E_jIs O_fThe number of products S that is insufficient in the next process when the day is stopped_j0The
[0066]
[Equation 57]

[0067]
Sought by
Device E_kIs O_fThe number of products S that is insufficient in the next process when the day is stopped_0kThe
[0068]
[Formula 58]

[0069]
And the above S_j0And S_okThe largest of them S_{i, i + 1} (S_{i, i + 1} = Max (S_jo, S_ok)) By a production line characterized by being determined according to, SolutionDecide.
[Action]
  In the present invention, immediately after the process, a device corresponding to the number of safety devices in order to prevent the long-term stoppage of the device of the process from affecting other processes is secured, and immediately before that, there is almost the same number of empty devices. Reserve a shelf. When a long-time stop occurs, the in-process devices are processed and reduced in the next process, and almost the same number of input-waiting devices are accumulated immediately before. By managing the production line so that the sum of the immediately following work and the immediately preceding work is approximately constant during normal operation and when the machine is stopped for a long time, it is possible to prevent the long stoppage of the equipment from affecting other processes. The On the other hand, in the past, since only the work in progress immediately before was taken into account, when the apparatus is stopped for a long time, the work in progress increases and the production line is stopped. In contrast, in the present invention, the sum of the immediately preceding work and the immediately following work is managed by comparing the planned number and the actual number, so there is no need to stop the line, and the effect of the device stop is It can be absorbed only by the process that occurs.
[0070]
In addition, the present invention provides a method for calculating the number of in-process devices from the operation result data of the apparatus. This method makes it possible to clearly define the planned in-process number, compared to a method in which the safe in-process number is approximately obtained from the transition of the in-process number and the processing number. In the present invention, the required number of stocker shelves is determined by calculating the number of safety work in progress. In this way, the necessary number of shelves can be facilitated, the stoppage of an apparatus in a certain process in the production line is prevented from extending to another process, and the throughput of the production line is improved. In addition, in the present invention, useless shelves are not provided, and the cost of the stocker is minimized.
[0071]
DETAILED DESCRIPTION OF THE INVENTION
[First embodiment]
Hereinafter, a case where the present invention is applied to manufacture of a TFT substrate constituting a liquid crystal display device will be described with reference to FIG.
Referring to FIG. 1, the TFT substrate production line is represented by process P.₁~ P₉Device E₁~ E_FourIs process P₂, P_Five, P₈Is processing. Of these, the process P₂Is the device E₁And E₂Processed, while process P_FiveThen device E₁~ E_FourAre all used. In FIG. 1, process P₁, P_Four, P₇Corresponds to the film formation process, and process P₂, P_FiveAnd P₈Is the photo process, also P_Three, P₆, P₉Corresponds to the etching process. Process P₁~ P₉The processing of the TFT substrate is performed by proceeding in order.
[0072]
In this embodiment, the processing rate of each process is determined by obtaining the load factor of each process and determining the usage ratio of each apparatus so as to equalize the load factor. Furthermore, the capacity of the production line is maximized by determining the appropriate number of planned work in progress (safe work in progress and basic work in progress).
First, each process capacity T_Ri, Process P_iDevice E against_jThe usage ratio of R_ijAnd device E_jT processing capacity_ijAs follows.
[0073]
T_R2= R_{twenty one}・ T_{twenty one}・ R_{twenty two}・ T_{twenty two}
T_R5= R₅₁・ T₅₁・ R₅₂・ T₅₂・ R₅₃・ T₅₃・ R₅₄・ T₅₄
T_R8= R₈₃・ T₈₃・ R₈₁・ T₈₁
Furthermore, each process P_iThe load factor of L_i, The required number of substrates processed N, where the other responsible operation rate is Ud_iThe
N_i[Sheet / day] = [process P_iDefined by the number of required processing in the production plan] / [number of operating days per month], the load factor L of each process_iCan be calculated by the following equation.
[0074]
L₂= N₂/ [T_R2× U_d2/ 100]
L_Five= N_Five/ [T_R5× U_d5/ 100]
L₈= N₈/ [T_R8× U_d8/ 100]
Where L₂= L_Five= L₈In other words, in order to equalize the load factor of each process, the apparatus E_ijUsage ratio R_{twenty one}, R_{twenty two}, R₅₁, R₅₂, R₅₃, R₅₄, R₈₃, R₈₁Determine. As a result, an optimal apparatus usage ratio that maximizes the throughput of the production line is required.
[0075]
Here, process P_iStandard processing capacity T_i[Sheets / day]
T_i= Max (T_ij, J = 1,... M),
Process P_iNumber of devices C_EPiThe
[0076]
[Formula 59]

[0077]
Defined in step P._iThe required number of devices
C_ENi= N_i・ (T_i・ U_d/ 100) [Stand]
Defined in
Then, device E_ijIs period O_fj[Days] The number of boards S that will be insufficient in the next process when stopped_ijIn other words, the number of substrates S accumulated in the previous process_ijIs
[0078]
[Expression 60]

[0079]
It can be calculated with However, period O_fjIs the longest equipment downtime expected within the production control period (usually about one month) in the production plan.
The number of substrates S for each device of j = 1, 2,._ijOf these, the largest quantity S_iThat is, S_i= Max (S_ij, J = 1, 2,... N), process P_iThe number of safe work in progress.
[0080]
And the process P_iImmediately after the safety work-in-process number S_iAlternatively, the production line is managed so as to secure an in-process corresponding to an integer representing the sum of the number of lot-organized substrates closest thereto. In addition, the process P_iImmediately before the process P_iY yield_iAs S_i/ B_iAn empty shelf corresponding to an integer corresponding to x100 or an integer representing the sum of the number of lot-organized substrates closest to this is secured.
[0081]
As a result of the management of the production line, the process P_iThe effect of stopping the device in other processes is avoided and the production throughput is maximized.
[Second Embodiment]
Next, P, which is a constrained process where work in progress tends to accumulate_sProcess and P_nTaking a process as an example, a method for managing the number of safe in-process, and the number of in-process when the apparatus is stopped and recovered will be described as a second embodiment of the present invention.
[0082]
P_sProcess and P_nIt is assumed that in-line handling is necessary between processes because time constraints are severe between the processes. P_sProcess and P_nTable 1 shows the processing capability of each apparatus in the process.
[0083]
[Table 1]

[0084]
First, calculate the longest unplanned offline time. At that time, MTBF is corrected by a coefficient of 90% reliability,
Of (E₀₁, Unplanned) = 2701n [1440 x 30 / (14118 x 0.634)] = 425 [min]
Of (E₀₂, Unplanned) = 1801n [1440 x 30 / (9792 x 0.675)] = 338 [min]
Of (E_TenUnplanned) = 6901n [1440 × 30 / (25260 × 0.539)] = 797 [min] is obtained.
[0085]
Among these, the longest plan in Table 1 is set to the longest stop time of each device, which is longer than the offline time.
P_sProcess is E_TenWith one, P_nProcess is E₀₁And E₀₂The two units are used for processing. P_sP from the end of process processing_nIf the process grace time until loading into the process equipment is within 40 [min], a safety mechanism cannot be placed between both processes. Therefore, E₀₁And E₀₂Is E_TenIt is necessary to calculate the capacity as a continuous virtual device.
[0086]
Device E_TenAnd device E₀₁E is a continuous virtual device₁₁, The throughput is T₁₁[Sheets / day], failure rate F₁₁And Device E_TenAnd device E₀₂E is a continuous virtual device₁₂, The throughput is T₁₂[Sheets / day], failure rate F₁₂It expresses by. E during continuous operation_TenThroughput is E₀₁And E₀₂Is greater than the sum of the throughputs of₁₁, E₁₂Tact is E₀₁And E₀₂Equal to the tact. Device E₁₁Non-failure rate (1-F₁₁) For each device (E_TenAnd E₀₁) Product of non-failure rate (1-F_Ten) ・ (1-F₀₁). Also, the incidental work time is calculated by subtracting the incidental work time to be performed at the same time from the incidental work time of each device.₁₁, T₁₂Can be calculated by the following formula (assuming that incidental work is performed independently).
[0087]

Process P also process P_sAnd process P_nA virtual process P that is continuous_snthink of. Virtual device E for this process₁₁And E₁₂Usage ratio R₁₁And R₁₂Are all 1. Virtual process P_snT processing capacity_{R, sn}  , The number of devices is C_{EP, sn}, The necessary number of devices is C_{EN, sn}, Load factor L_snAnd
[0088]

Process P_snNumber of devices C_{EP, sn}The standard processing capacity is T_snThen,

Assuming that the required number of processes per month is 27000 [sheets / day], the number of operating days in the month is 30 days, and the operation rate other responsibility Ud is 90%, the virtual process P_snNecessary number of processed sheets per day_snIs 900 [sheets / day]

Device E_Ten, E₀₁, E₀₂Virtual process P when each device is stopped_snEstimate the safety in-process. In fact, P_nNumber of safety in-process S immediately after the process_sSet the in-process equivalent to P_sAnd P_nThink of it as a safety device for both processes
[E_TenStop] Safety in-process S_TenIs

Based on the above results, E₀₂E is not affected, but E₀₁And E_TenIt can be seen that the effects of the stoppage are the same, and the safety work is required to be 523 [sheets] and about 26 [lots]. Ie P_nImmediately after the process, a work in process of 26 [lots]_s26 shelves are required immediately before the process.
[Third embodiment]
Next, an example of the basic in-process calculation is the virtual process P of the first embodiment._snShow about. Table 2 shows the basic data of each device for calculation.
[0089]
Table 3 also shows virtual device E.₁₁, E₁₂And virtual process P_snThe calculation result of the basic work in progress is shown.
[0090]
[Table 2]

[0091]
[Table 3]

[0092]
For the virtual device, the entrance side device E of the two consecutive devices_TenPending work in progress S_{W, 10}, Waiting-to-convey S_{T, 10}To virtual device E₁₁(E₁₂) S_{W, 11}(S_{W, 12}), S_{T, 11}(S_{T, 12}). Outlet side device E₀₁(E₀₂) Waiting for unloading S_{F, 01}(S_{F, 02}) For virtual device E₁₁(E₁₂) S_{F, 11}(S_{F, 12}). Also, the inlet side device E_TenIn-process work in progress S_{P, 10}, Carry-out in process S_{F, 10}And outlet side device E₀₁(E₀₂) Pending work S_{W, 01}(S_{W, 02}) In-process S_{P, 01}(S_{P, 02}) Is added to the virtual device S_{P, 11}(S_{P, 12}).
[0093]
Virtual process P_snFor virtual device E₁₁, E₁₂Inlet side equipment E_TenIs common, E₁₁, E₁₂From the sum of the number of work in progress (processing, waiting for processing, waiting for unloading, waiting for transport), E₁₁And E₁₂P minus the common work in progress_snThe number of devices in progress (processing, waiting for processing, waiting for unloading, waiting for transport).
P_snRequired operating rate U_snIs 90% responsible for other processes,
U_sn= 90 ・ C_{EN, sn}/ C_{EP, sn}= 90 ・ 1.079 / 1219 = 79.66 [%] (4)
Non-failure rate as a whole (1-F_sn) Is a virtual device E₁₁And E₁₂Take the average of the non-failure rate.
[0094]
(1-F_sn) = (0.981 x 0.973 + 0.982 x 0.973) /2=0.955
Therefore, the virtual process P_snBasic work in progress S_{K, sn}Can be calculated by the following equation.
S_{K, sn}= 0.7966 x (7 + 1 + 2 + 1) x 0.955 = 11 x 0.7608 = 8.4 [lot] (5)
[Fourth embodiment]
Next, an embodiment for calculating the basic schedule of the process from the safety in-process and the basic in-process will be described in the case of Examples 2 and 3. P_sProcess and P_nIt can be seen that the in-process of the virtual process including the processes is 8.4 [lot] for the basic in-process and 26 [lot] for the in-process safety. Since the number of processing lots required per day is 45 [lots / day] by dividing 900 [sheets / day] by 20 [sheets / lot], the standard schedule K_snCan be calculated by the following equation.
[0095]
K_sn= 8.4 / 45 + 26/45 = 0.1867 + 0.5778 = 0.7644 [Sun]
P_sProcess and P_nBy placing the above-mentioned safety device in the process and performing schedule management with a standard schedule of 0.7644 [days], it is possible to prevent the influence of the long stoppage of the apparatus from affecting other processes.
[Fifth embodiment]
Next, referring to FIG. 2, a fifth embodiment of the present invention will be described with reference to FIG. 2 as a fifth embodiment of the present invention.
[0096]
2 shows P_snShows the planned work in progress before and after the process. P_snBasic work in process S_{K, sn}Is the sum S of each in-process waiting for transport, waiting for processing, being processed, and waiting for unloading_{T, sn}+ S_{W, sn}+ S_{P, sn}+ S_{F, sn}be equivalent to. P_snThe reference schedule for the process is given by the sum of the schedule corresponding to the basic work in progress and the schedule corresponding to the safety work in progress. The status of each lot is (... → [Basic process in process of previous process]) → [Safe process in process of previous process] → [P_snProcess basic work in progress] → [P_snThe process progresses by sequentially moving in the order of “process safety in process” → [basic process in the subsequent process] → [safe process in the post process] →.
[0097]
FIG. 3 shows the actual work in progress that can be actually monitored (collected) on the current process management system. The in-process in-process that can be collected includes in-process in-process in each process (operation) on the process management system and in-process in-process. From these in-process / wait-for-process in-process, the actual in-process in progress corresponding to the basic in-process / safe in-process of FIG. 2 can be calculated.
P_snNumber of basic work in process S_{K, sn}Actual work in progress corresponding to S_{Z, sn}Is {P_sIn-process S in process_{Z, s11}) + (P_nIn-process waiting S_{Z, n + 0}) + (P_nIn-process S in process_{Z, n + 1}) +1}. S_{Z, sn}Is the number of basic work in progress S_{K, sn}Schedule management to match 1 is the actual value S_{Z, sn}To P_snIn-process waiting for delivery S_{T, sn}Is not included. S_{Z, sn}Process P_snThis is called in-process work in progress.
[0098]
P_snNumber of process safety in-process S_snIn-process, S_{Z, sna}{(In-process waiting for the previous process S_{Z, as0}) -1}. S_{Z, sna}Process P_snImmediately after, it is called a work in process.
P_sPre-process P of process_srSafety in-process S_srActual work in progress corresponding to S_{Z, sra}{(P_sIn-process waiting S_{Z, s10}) -1}. S_{Z, sra}Process P_srImmediately after, it is called a work in process.
[0099]
(S_sn-S_{Z, sna}) ≧ 20 (P_snIn-process S immediately after the process_{Z, sna}In addition, the safety in-process S_sn1 [lot] is available), P_snIn-process S in process_{Z, sn}Advance 1 [lot] from_snIn-process S immediately after the process_{Z, sna}Put in.
Similarly (S_{K, sn}-S_{Z, sn}) ≧ 20 (P_snIn-process S in process_{Z, sn}Basic work in progress S_{K, sn}(If there is more than 1 [lot] available) P_srIn-process S immediately after the process_{Z, sra}1 [lot] from P_sn(Slight Etch)_snIn-process S in process_{Z, sn}Put in.
[0100]
Generally process P_iSafety in-process (plan) S_iAnd process P_iIn-process (actual) S_{Z, ia}, Process P_iBasic work in progress (plan) S_{K, i}And in-process in-process (actual) S_{Z, i}Are compared in order to confirm that there is 1 [lot] available for the planned work in progress, and the status of the lot is changed to [P_i-1] Immediately after the process → P_iIn-process work in progress, P_iProcess in process → P_iImmediately after the process, it is moved in order and progressed. As a result, the lot progress can be made in the subsequent process drawing.
[Sixth embodiment]
Next, P_snTaking a process as an example, a schedule management method in the case where a long stop actually occurs in the apparatus will be described. E_TenIt is assumed that a failure stop of 800 [min] has occurred in the apparatus.
[0101]
P in FIG._snShows planned in-process (safety in-process and basic in-process) and empty shelves before and after the process. The empty shelf is for storing the lot that is collected immediately before the process when the apparatus is stopped for a long time, and is equal to the number of safety in-process divided by the number of basic organization 20 of the lot. In addition, FIG._snThe state of actual work before and after the process is shown.
E_TenWhile the device is stopped, P_snProcessing of the process stops. P_snProcesses other than the process are processed as planned. P_snIn-process in-process S of the subsequent process_{Z, as}Basic work in progress S_{K, as}Every time there is a space for_snIn-process S immediately after the process_{Z, sna}Lot status is S_{Z, as}Move on.
[0102]
On the other hand, P_snIn-process S in process_{Z, sn}Among these, the status of 2 [lot] waiting for conveyance and waiting for processing does not change while the apparatus is stopped. The status of the remaining 9 lots being processed and waiting to be removed is P_snIn-process S immediately after the process_{Z, sna}Move on sequentially. Therefore, P_snIn-process S in process_{Z, sn}Is 2 [lots]. Subsequent work in progress S_{Z, sn}In-process S immediately after_{Z, sna}S cannot be replenished, so S_{Z, sna}Will decrease.
[0103]
P_snImmediately before the process, an empty shelf equal to the number of in-process safe work is prepared. When the equipment is stopped for a long time, the previous process P_srIn-process S immediately after_{Z, sna}Transfer lots from. In-process devices stored in empty shelves_snCalled work-in-process immediately before, S_{Z, snb}It expresses by.
P_snIn-process S immediately after the process_{Z, snb}Is P_snNumber of process safety in-process S_snUntil S is equal to_{Z, sra}To S_{Z, snb}The lot status will be transferred to. The transfer timing is P_snIn-process in-process S of the subsequent process_{Z, as}Basic work in progress S_{K, as}At the timing when there is a vacancy for_snIn-process S immediately after the process_{Z, sna}The status of the lot of S_{Z, as}It is only necessary to move to the same timing. As a result, P_snThe entire line can be produced in a subsequent process without being affected by process stoppage.
[0104]
However, S_{Z, snb}≧ S_snWhen it becomes (when the number of previous work in process exceeds the number of safe work in process), the entire line is stopped. Actually S_snIs set in accordance with the longest expected stop time, so the entire line should not stop in principle.
E after 800 [min]_TenP until the device is restored_snSum of in-process and in-process in process immediately after process, [S_{Z, sna}+ S_{Z, sn}] Is reduced by 500 [sheets] and 25 [lots]. Actually in-process S_{Z, sna}Decreases by 16 [lots] to 10 [lots], P_snIn-process S in process_{Z, sn}Is reduced by 9 [lots] to 2 [lots]. And P_snIn-process S immediately before the process_{Z, snb}Increases from 0 [lot] to 25 [lot].
[Seventh embodiment]
An embodiment of a method for recovering the number of devices that have been reduced after the previous stoppage of the device to a safe number of devices will be described. In Example 6, V₆, E_TenAfter device restoration, P_snIt is necessary to recover the required number of in-process by increasing the operation rate of the process from normal. That is, P_snIn-process S immediately before the process_{Z, snb}The status of 25 [lot] of the in-process S_{Z, sn}After going through, in-process S_{Z, sna}Move to. Naturally, the remaining capacity of processing 900 [sheets / day] necessary for maintaining the operation of the entire line is directed.
[0105]
Here, P_snThe recovery time when the operation rate of the process is increased to 100% is calculated. P_snThe required operating rate of the process is 80% from the equation (4), and the remaining power that can be turned around is 20%. The number of work in process to be recovered is 500 [sheets], P_snThe standard processing capacity of the process is T from equation (1)._sn= 927 [sheets / day], the number of devices is C from equation (2)._{EP, sn}= 1.219 [unit]
K = 500 / {1.219 ・ 927 (1-80 / 100)} = 2.21 [Sun] (6)
Therefore, P in about 2.2 [days]_snIn-process S immediately after the process_{Z, sna}Can be recovered up to 523 [in-process] safe work in progress.
[0106]
As mentioned above, although this invention was demonstrated about the preferable Example, this invention is not limited to said Example, A various deformation | transformation and change are possible within the summary as described in a claim.
[0107]
【The invention's effect】
According to the features of the present invention as set forth in claims 1 to 21, immediately after a process, a process corresponding to the number of safety processes in order to prevent the influence of a long-time stoppage of the apparatus of the process on other processes is ensured. However, almost the same number of empty shelves are secured immediately before this. In this way, when the apparatus is stopped for a long time, the in-process devices are processed and reduced in the next process, and almost the same number of input-waiting devices are accumulated immediately before. At that time, by controlling the production line so that the sum of the immediately in-process and the immediately-in-process is approximately constant during both normal and long-term machine stoppages, long-time machine stoppages affect other processes. Is avoided. That is, according to the present invention, the sum of the immediately preceding work and the immediately following work is managed by comparing the planned number and the actual number, so there is no need to stop the line, and the device stop is caused by the effect of the device stop. It can be absorbed only by the process.
[0108]
In addition, the present invention provides a method for calculating the number of in-process devices from the operation result data of the apparatus. This method makes it possible to clearly define the planned in-process number, compared to a method in which the safe in-process number is approximately obtained from the transition of the in-process number and the processing number. In the present invention, the required number of stocker shelves is determined by calculating the number of safety work in progress. In this way, the necessary number of shelves can be facilitated, the stoppage of an apparatus in a certain process in the production line is prevented from extending to another process, and the throughput of the production line is improved. In addition, in the present invention, useless shelves are not provided, and the cost of the stocker is minimized.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a production management method according to a first embodiment of the present invention.
FIG. 2 is a diagram (part 1) for explaining a production management method according to a fifth embodiment of the present invention;
FIG. 3 is a diagram (part 2) for explaining a production management method according to a fifth embodiment of the present invention;
FIG. 4 is a diagram (part 1) for explaining a production management method according to a sixth embodiment of the present invention;
FIG. 5 is a diagram (No. 2) for explaining a production management method according to the sixth embodiment of the present invention;
[Explanation of symbols]
P₁~ P₈  Process

Claims (11)

By including the process group P _i (i = 1, 2,... M) and flowing the product through the process group, the apparatus group E _j (j = 1, 2,... N) is used for the product. A production line production management method for performing necessary processing,
Between one step P _i and the next step P _{i + 1,} the safety-process number corresponding to the number of products that will be missing in the step P _{i + 1} as a result of the stopping device in the step P _i,
Device _{E j} steps _{P i} with respect to the processing capacity of _{T ij,} the device _{E j,} the use for the process _{P i} ratio as _{R ij,} the throughput _{T Ri} step _{P i}

Sought by
The standard processing capacity of process P _i is T _i , and the number of devices C _EPi of process P _i is

Sought by
In the production plan, the number of necessary processes per day in the process P _i is N _i , U _d is the other responsible operation rate, and the required number of equipment C _ENi of the process P _i is

Sought by
If the equipment E _j is shut down for _Ofj days,

And secured according to the largest one of the above S _ij S _i (S _i = Max (S _ij , j = 1,2,... N))
Furthermore, a production management method characterized by securing the number of empty shelves corresponding to the S _i immediately before the step P _i . The number of the vacant shelves, the process yield of _{P i} as _{B i,} 100S _i / production management method according to claim 1, characterized in that is determined in accordance with _{B i.} The apparatus usage ratio R _ji is determined such that the number of safety in-process S _i is minimized within a range that satisfies the processing capability T _Ri required in the process P _i . The production management method according to 1 or 2 . The stop period O _fj, of the planned off-line time specified in the SEMI E10-96 Standard unplanned offline time longer and production management method according to claim 1 or 2, wherein the to. The stop period O _fj is defined from the unplanned offline time average MTUO, the average unplanned downtime intervals MTUD, a management period P date of production on the production plan, a k to SEMI E10-96 Standard As the lower limit of the reliability of the average failure interval,
O _fj (day) = MTUO · ln {P / (k · MTUD)}
The production management method according to claim 1, wherein the production management method is obtained by: Each process P _i  In apparatus E _j  Regarding the use of Step P _i  In the case where restrictions are imposed by the type of product processed in the above process group P _i  Instead of (i = 1, 2,..., M), the process type group P obtained by subdividing the process group according to the type of product _i  (I = 1, 2,... Z), and the process type group P _i  The production management method according to claim 1, further comprising a step of calculating the safety work in progress and the basic work in progress for each of the process varieties included in the process. The process _{P i} to process the unit group _{E j (j = 1,2 ··· n} ) is, in the next step _{P i + 1} of the unit group _{E k (k = 1,2 ··· m} ) is a production line for processing In the production management method, when a safety device cannot be set between the process P _i and the process P _{i + 1} , a virtual process P _{i, i + 1} and a virtual device E _jk are defined, and the virtual process P _{i , I + 1} for the number of safe work in progress,
_Assuming that the processing capacity of the virtual device E _{j, k for} the virtual process P _{i, i + 1} is T _jk , and the usage ratio of the virtual device E _jk to the virtual process P _{i, i + 1} is R _{j, k} , the virtual process P _{i, i + 1} processing capacity _{TRi, i + 1}

Sought by
Assuming that the standard processing capacity of the virtual process P _{i + 1} is T _{i, i + 1} , the number of devices C _{EPi, i + 1} of the virtual process P _{i , i + 1} is

Sought by
In the production plan, the number of necessary processes per day in the virtual process P _{i, i + 1} is N _{i, i + 1} , U _d is the other responsible operation rate, and the required number of devices C _{ENi, i + 1} in the virtual process P _{i , i + 1} is

Sought by
The product number S _j0 the device E _j is insufficient in the next step when stopping O _f Date

Sought by
The product number S _0k that device E _k is insufficient in the next step when stopping O _f Date

_{And secured according} to the largest one of S _j0 and S _ok S _{i, i + 1} (S _{i, i + 1} = Max (S _jo , S _ok )),
Furthermore, a production management method characterized by securing a number of empty shelves corresponding to the above S _{i, i + 1} immediately before the step P _i . By including the process group P _i (i = 1, 2,... M) and flowing the product through the process group, the apparatus group E _j (j = 1, 2,... N) is used for the product. in a production line which performs the necessary processing Te, between one step P _i and the next step P _{i + 1,} the step number of the product that will be missing in the P _{i + 1} as a result of the stopping of the apparatus in the step P _i A method for securing the number of safe work in progress on a production line ,
Device _{E j} steps _{P i} with respect to the processing capacity of _{T ij,} the device _{E j,} the use for the process _{P i} ratio as _{R ij,} the throughput _{T Ri} step _{P i}

Sought by
The standard processing capacity of process P _i is T _i , and the number of devices C _EPi of process P _i is

Sought by
In the production plan, the number of necessary processes per day in the process P _i is N _i , U _d is the other responsible operation rate, and the required number of equipment C _ENi of the process P _i is

Sought by
If the equipment E _j is shut down for _Ofj days,

The calculated, maximum one _{S i (S i = Max (} S ij of the _{S ij,} and wherein the securing according to j = 1,2 ··· n), safety-process speed of the production line How to secure . The process _{P i} to process the unit group _{E j (j = 1,2 ··· n} ) is in the next step _{P i + 1} of the unit group _{E k (k = 1,2 ··· m} ) is a production line for processing When a safety device cannot be set between the process P _i and the process P _{i + 1} , a virtual process P _{i, i + 1} and a virtual device E _jk are defined and safe for the virtual process P _{i, i + 1} . A method for securing the number of safe work in progress on the production line to secure the number of work in progress ,
_Assuming that the processing capacity of the virtual device E _{j, k for} the virtual process P _{i, i + 1} is T _jk , and the usage ratio of the virtual device E _jk to the virtual process P _{i, i + 1} is R _{j, k} , the virtual process P _{i, i + 1} processing capacity _{TRi, i + 1}

Sought by
Assuming that the standard processing capacity of the virtual process P _{i + 1} is T _{i, i + 1} , the number of devices C _{EPi, i + 1} of the virtual process P _{i , i + 1} is

Sought by
In the production plan, the number of necessary processes per day in the virtual process P _{i, i + 1} is N _{i, i + 1} , U _d is the other responsible operation rate, and the required number of devices C _{ENi, i + 1} in the virtual process P _{i , i + 1} is

Sought by
The product number S _j0 the device E _j is insufficient in the next step when stopping O _f Date

Sought by
The product number S _0k that device E _k is insufficient in the next step when stopping O _f Date

Sought by
In the production line, the number of the safety work in _progress is _{ensured according} to the largest one of S _j0 and S _ok S _{i, i + 1} (S _{i, i + 1} = Max (S _jo , S _ok )) How to secure the number of safe work in progress . By including the process group P _i (i = 1, 2,... M) and flowing the product through the process group, the apparatus group E _j (j = 1, 2,... N) is used for the product. Production line that performs the necessary processing,
Between one step P _i and the next step P _{i + 1,} the process P _{i + 1} free equal to the safety-process speed corresponding to the number of products that will be missing in the result of the stopping of the apparatus in the step P _i With shelves,
The last minute of the one step P _i, with equal empty shelves to the safety-process number,
Equipment _{E j} steps _{P i} with respect to the processing capacity of _{T ij,} the device _{E j,} the use for the process _{P i} ratio as _{R ij,} the throughput _{T Ri} step _{P i}

Sought by
The standard processing capacity of process P _i is T _i , and the number of devices C _EPi of process P _i is

Sought by
In the production plan, the number of necessary processes per day in the process P _i is N _i , U _d is the other responsible operation rate, and the required number of equipment C _ENi of the process P _i is

Sought by
If the equipment E _j is shut down for _Ofj days,

Sought by
Said safety-process number, characterized in that it is set to be the largest of _S i of the _{S ij (S i = Max (} S ij, j = 1,2 ··· n) Production line. The process _{P i} aforementioned processing unit group _{E j (j = 1,2 ··· n} ) is then the next step _{P i + 1} of the unit group _{E k (k = 1,2 ··· m} ) is processed, in which a production line can not be set safety contrivance hunting between said step P _i process P _{i + 1,}
Wherein between the step P _{i + 1} and the next step P _{i + 2,} the process P _{i + 1} free shelf equal to the safety-process speed corresponding to the number of products that will be missing in the result of the stopping of the apparatus in the step P _i With
The last minute of the one step P _i, with equal empty shelves to the safety-process number,
The number of safe work in progress is
A virtual process P _{i, i + 1} and a virtual device E _jk are defined, and for the virtual process P _{i, i + 1} ,
_Assuming that the processing capacity of the virtual device E _{j, k for} the virtual process P _{i, i + 1} is T _jk , and the usage ratio of the virtual device E _jk to the virtual process P _{i, i + 1} is R _{j, k} , the virtual process P _{i, i + 1} processing capacity _{TRi, i + 1}

Sought by
Assuming that the standard processing capacity of the virtual process P _{i + 1} is T _{i, i + 1} , the number of devices C _{EPi, i + 1} of the virtual process P _{i , i + 1} is

Sought by
In the production plan, the number of necessary processes per day in the virtual process P _{i, i + 1} is N _{i, i + 1} , U _d is the other responsible operation rate, and the required number of devices C _{ENi, i + 1} in the virtual process P _{i , i + 1} is

Sought by
The product number S _j0 the device E _j is insufficient in the next step when stopping O _f Date

Sought by
The product number S _0k that device E _k is insufficient in the next step when stopping O _f Date

A production line characterized in that the production line is determined in accordance with the maximum value S _{i, i + 1} (S _{i, i + 1} = Max (S _jo , S _ok )) of S _j0 and S _ok .

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