JP4158515B2

JP4158515B2 - 2-fluid nozzle for cleaning and cleaning method

Info

Publication number: JP4158515B2
Application number: JP2002372324A
Authority: JP
Inventors: 久志戸田; 範明永瀬
Original assignee: Mitsubishi Chemical Corp
Current assignee: Mitsubishi Chemical Corp
Priority date: 2002-12-24
Filing date: 2002-12-24
Publication date: 2008-10-01
Anticipated expiration: 2022-12-24
Also published as: JP2004202316A

Description

【０００１】
【発明の属する技術分野】
本発明は加圧気体を用いて洗浄液を加圧して噴出する、洗浄用２流体ノズル及び洗浄方法に関するものである。さらに詳しくは洗浄液中に気泡（キャビテーション）を発生させて洗浄を行う洗浄用２流体ノズルに関するものである。
【０００２】
【従来の技術】
埃や汚れなどの付着物を除去する洗浄用ノズルとして、洗浄用２流体ノズルは広く用いられている。図２は、従来から広く用いられる洗浄用２流体ノズルの構造の一例である。洗浄用２流体ノズルの本体部は内筒部７と外筒部８の２重円筒構造となっている。内筒部７及び外筒部８の一方の端部は円錐形状に先細りになっており、内筒部７の先端には開口が設けられ、開口の外側が洗浄液と加圧気体が混合する混合部５である。混合部５を経た外筒部８の先端は直管部９となっており、直管部９の先端に噴出口６が設けられている。内筒部７の内部は洗浄液供給部３であり、内筒部７のもう一方の端部には洗浄液供給口１が設けられている。内筒部７と外筒部８の間が加圧気体供給部４であり、外筒部８には加圧気体供給口２が設けられている。
【０００３】
本発明に係る洗浄用２流体ノズルの使用方法を説明する。
先ず、洗浄液供給口１にホースなどを接続し、洗浄用２流体ノズルに洗浄液を供給する。洗浄液は洗浄液供給口１より洗浄液供給部３に供給される。また、加圧気体供給口２より、洗浄用２流体ノズルに洗浄液よりも高圧の加圧気体を供給する。加圧気体は加圧気体供給口２より加圧気体供給部４に供給される。洗浄用２流体ノズルに供給された洗浄液と加圧気体は混合部５で混合される。加圧気体は洗浄液よりも圧力が高いため、加圧気体と混合した洗浄液は加圧気体により加速され、その速度を増して洗浄用２流体ノズルの直管部９を経て、噴出口６より噴出する。洗浄用２流体ノズルより噴出した洗浄液は被洗浄物に衝突し、被洗浄物に付着している付着物を除去する。
【０００４】
また、図３は、従来から用いられている洗浄用２流体ノズルの構造の他の一例である。
この洗浄用２流体ノズルは、混合部１５と加速部１４から構成されており、混合部１５には加圧気体流入口１６と洗浄液流入口１７が設けられている。
加圧気体流入口１６から加圧気体を、洗浄液流入口１７から洗浄液をそれぞれ混合部１５に流入する。流入された加圧気体と洗浄液は混合部１５で混合され、洗浄液の液滴が形成される。混合部１５で形成された洗浄液の液滴は、加圧気体と共に加速部１４に進み、洗浄液の液滴は加圧気体により加速されて噴出する。洗浄用２流体ノズルより噴出した洗浄液の液滴は、被洗浄物に衝突し、被洗浄物に付着している付着物を除去する（特許文献１）。
【０００５】
【特許文献１】
特開平１０−１５６２２９号公報
【０００６】
【発明が解決しようとする課題】
しかし、以上で説明したような従来の洗浄用２流体ノズルでは洗浄力不足が問題となることがあった。上述したように、従来の洗浄用２流体ノズルは、加圧気体の圧力を利用して洗浄液を加速し洗浄を行う。よって、加圧気体の圧力が十分に高くない場合、洗浄液を十分に加速できないこととなってしまい、洗浄力が不足することとなる。この洗浄力を上げるには加圧気体の圧力を上げればよいが、加圧気体の圧力を上げるためには、コンプレッサーの能力を上げる等の処置が必要な場合が多く、そのコストが問題となってくる。また、加圧気体の圧力を上げた場合、洗浄用２流体ノズル自体も高圧仕様にしなければならないため、洗浄用２流体ノズルの製造コストが高くなるという問題も起きてしまう。
【０００７】
本発明は上記課題を解決する為、洗浄用２流体ノズルにおいて、洗浄液中に加圧気体を混入させることにより、加圧気体等の圧力を上げることなく、洗浄力を向上させる洗浄用２流体ノズル及び洗浄方法を提供することを目的とする。
【０００８】
【課題を解決するための手段】
本発明の要旨は、噴出口から洗浄液を加圧気体により加圧して噴出し、被洗浄物に付着した付着物を除去する洗浄用２流体ノズルにおいて、該洗浄用ノズルが、洗浄液と加圧気体とを混合させる混合部と、該混合部に洗浄液を供給する洗浄液供給部と、該混合部に加圧気体を供給する加圧気体供給部と、該加圧気体供給部に加圧気体を供給する第一加圧気体供給口と、該洗浄液供給部に洗浄液を供給する洗浄液供給口と、を有し、該洗浄液供給部に該加圧気体を供給する第二加圧気体供給口を有することを特徴とする洗浄用２流体ノズルに存する。
【０００９】
また、本発明の別の要旨は、上記洗浄用２流体ノズルを用いた洗浄法に存する。
本発明によれば、洗浄液供給部に加圧気体を供給することにより、洗浄液中に小さな気泡（キャビテーション）を発生させることができる。そして、この気泡が混合部で破裂する際に衝撃波を発生することにより、付着物を除去しやすくなる。さらに、気泡が被洗浄物にぶつかる際に起きる気泡の破裂する事により、付着物を除去しやすくなる。これにより、洗浄用ノズルの洗浄力を向上させることができる。
【００１０】
本発明の洗浄用２流体ノズルはその洗浄能力の高さから、微細な付着物等が問題となるような、磁気記録媒体や光記録媒体などの精密製品の製造ラインでの使用に適している。
なお、本発明における加圧気体とは、その洗浄用２流体ノズルの使用場所における大気圧より大きい圧力の気体のことを言う。
【００１１】
【発明の実施の形態】
以下、本発明について詳細に説明する。
本発明に係る洗浄用２流体ノズルを図を用いて説明する。図１は本発明に係る洗浄用２流体ノズルの一形態の構造を示す概略図である。
図１に示すように、本発明に係る洗浄用２流体ノズル本体部は内筒部７と外筒部８の２重円筒構造となっている。内筒部７及び外筒部８の一方の端部は円錐形状に先細りになっており、内筒部７の先端には開口が設けられており、開口の外側が洗浄液と加圧気体が混合する混合部５である。混合部５を経た外筒部８の先端は直管部９となっており、直管部９の先端に噴出口６が設けられている。内筒部７の内部は洗浄液供給部３であり、内筒部７のもう一方の端部には洗浄液供給口１が設けられている。内筒部７と外筒部８の間が加圧気体供給部４であり、外筒部８には第一加圧気体供給口１２が設けられている。加圧気体供給部４は、第二加圧気体供給口１３を介して気泡発生用加圧気体供給路１０により洗浄液供給部３につながっており、その途中に圧力調整手段として気泡発生用加圧気体圧力調節部１１が設けられている。
【００１２】
次に、本発明に係る洗浄用２流体ノズルを用いた洗浄方法について説明する。
洗浄液供給口１にホースなどを接続し、洗浄用２流体ノズルに洗浄液を供給する。洗浄液は洗浄液供給口１より洗浄液供給部３に供給される。また、第一加圧気体供給口１２より、ノズルに洗浄液よりも高圧の加圧気体を供給する。加圧気体は第一加圧気体供給口１２より加圧気体供給部４に供給される。加圧気体供給部４に供給された加圧気体の一部は、第二加圧気体供給口１３を介して気泡発生用加圧気体供給路１０を通過し、洗浄液供給部３に供給される。洗浄液に供給された加圧気体はサブμｍ程度の小さな気泡となり、洗浄液中に存在する。洗浄液中に存在する気泡は、洗浄液と共に混合部５へと移動する。混合部５に達した気泡は圧力の低下と共に急激に膨張し、その気泡の一部は混合部５で破裂をする。この気泡が破裂する際に、洗浄液に衝撃波（パルス）が発生する。パルスが発生した洗浄液は加圧気体と混合部５によって混合される。洗浄液は加圧気体により加速され、その速度を増してノズルの噴出口６より噴出する。ノズルより噴出した気泡を含んだ洗浄液は被洗浄物に衝突し、洗浄液中の気泡は衝突した際に破裂する。なお、洗浄液中に発生する気泡の大きさは、通常０．０１μｍ〜１０μｍ程度である。
【００１３】
気泡が混合部５で破裂することにより発生する洗浄液のパルスとは、洗浄液の噴出圧が高い状態と低い状態を繰り返している状態を示している。この気泡が破裂により発生する洗浄液の噴出圧が高い状態の圧力は、気泡が混合部５で破裂せずパルスを有さない状態の洗浄液の噴出圧よりも高くなる。これにより加圧気体の圧力等を上げることなく、洗浄液の噴出圧を上げることができ、洗浄力が向上することとなる。また、混合部５で破裂せずに、洗浄液に含まれた状態で噴出された気泡は、被洗浄物に衝突すると破裂する。この気泡が破裂する際に発生する衝撃により、付着物が被洗浄物から離脱しやすくなる。これにより洗浄力が向上することとなる。
【００１４】
本発明の特徴は洗浄液供給部３へ加圧気体を供給する第二加圧気体供給口１３を有することにある。この第二加圧気体供給口１３を有することにより、上述したような洗浄液のパルス及び気泡の破裂による洗浄力の向上を図ることができる。
洗浄液供給部３へ加圧気体を供給する第二加圧気体供給口１３の後に続く気泡発生用加圧気体供給路１０には、圧力調整手段としての気泡発生用加圧気体圧力調整部１１を設け、洗浄液供給部３に供給する加圧気体の圧力を調節可能な構造とすることが好ましい。洗浄液供給部３に供給する加圧気体の圧力を調節することにより、洗浄液中に発生する気泡の量や大きさを調節することができるため、洗浄液に発生するパルスの周波数やノズルより噴出された後の洗浄液中の気泡の量をコントロールすることができる。つまり、洗浄力の強さを調節することが可能となる。圧力調整手段である気泡発生用加圧気体圧力調節部１１の機構としては、圧力を調節できる機構であれば何れの機構でもかまわないが、操作が容易であり構造も簡素なものとすることができることから、ニードル弁をネジ式機構により移動可能な構造とし、ニードル弁を移動させて気泡発生用加圧気体供給路１０断面とニードル弁の隙間の面積を変化させ、洗浄液供給部３へ供給する加圧気体の圧力を調節できる機構とすることが好ましい。
【００１５】
図１においては、洗浄液供給部３へ加圧気体を供給する第二加圧気体供給口１３及び気泡発生用加圧気体供給路１０は一つずつしか設けてないが、気泡が発生できればその数に制限はなく、それぞれ２つ以上設けていても良い。また、加圧気体が流入できるのであれば、その形状はいずれの形状でも良い。
洗浄液に発生させるパルスの周波数は通常２０Ｈｚ以上、好ましくは５０Ｈｚ以上である。あまり周波数が低いと、パルスによる衝撃が付着物に効果的に伝わらないおそれがある。この範囲であれば、付着物にパルスによる衝撃を効果的に伝え、洗浄力の向上を図ることができる。ただし、周波数は通常２００Ｈｚ以下、好ましくは１５０Ｈｚ以下である。あまり周波数が高すぎると、パルスが付着物に与える衝撃が小さくなってしまう。この範囲であれば、洗浄液に適切なパルス効果による洗浄力の向上を期待することができる。
【００１６】
洗浄液供給部３に供給する加圧気体の圧力は洗浄液の圧力よりも高くなけらばならない。洗浄液よりも圧力が低いと洗浄液中に加圧気体が流入できないため、気泡が発生しないからである。洗浄液供給部３に供給する加圧気体の圧力と洗浄液の圧力の差は、通常２００ｋＰａ以上、好ましくは３００ｋＰａ以上である。加圧気体の圧力と洗浄液の圧力差がこの範囲以上であれば、加圧気体が洗浄液中に適度に流入するため、微細な気泡を適度に発生させることができ、表面が軟質の物や微細な付着物に対しても効果的に洗浄を行うことができる。また、洗浄液供給部３に供給する加圧気体の圧力と洗浄液の圧力の差は通常１２００ｋＰａ以下であり、好ましくは１０００ｋＰａ以下である。加圧気体の圧力と洗浄液の圧力差がこの値以下であれば、加圧気体の過度の流入を防ぎ、適切な量の気泡を発生させることができる。
【００１７】
本発明の洗浄用２流体ノズルの構造は、上述した様に洗浄液供給部３と加圧気体供給部４を、第二加圧気体供給口１３を介して気泡発生用加圧気体供給路１０により繋げるような構造とすることが好ましい。この様な構造とすることにより、第一加圧気体供給口１２から加圧気体を供給するだけで、洗浄液供給部３にも同時に加圧気体を供給することができるため、加圧気体供給ラインの構造を簡単にすることができる。
【００１８】
ただし、第一加圧気体供給口１２と第二加圧気体供給口１３にそれぞれ加圧気体供給ラインを設けて、洗浄液中に加圧気体を供給する構造としても、当然に本発明の効果は期待できる。この場合は第二加圧気体供給口１３の加圧気体供給ラインに減圧弁等の圧力調整手段を設け、供給する加圧気体の圧力を調整できるようにしておくことが好ましい。
【００１９】
気泡発生用加圧気体供給路１０の径は、その下限値は通常０．３ｍｍ以上、好ましくは０．５ｍｍ以上であり、上限値は通常２．０ｍｍ以下であり、好ましくは１．５ｍｍ以下である。この範囲であれば、適切な量の加圧気体を供給することができるため、洗浄液中に安定して気泡を発生させることができる。
洗浄用２流体ノズルの内筒部の開口径の下限値は、通常１．０ｍｍ以上、好ましくは１．５ｍｍ以上であり、上限値は３．０ｍｍ以下、好ましくは２．５ｍｍ以下である。この範囲であれば、適量の気泡を含む洗浄液を混合部５に供給でき、気泡の破裂によるパルスの発生を効果的に行いやすくなるからである。
【００２０】
洗浄用２流体ノズルの噴出口の径の下限値は、通常２．０ｍｍ以上、好ましくは２．５ｍｍ以上であり、上限値は６．０ｍｍ以下、好ましくは５．５ｍｍ以下である。この範囲であれば、洗浄液の勢いを損なうことなく、洗浄液の広がりを抑えつつ精度良く被洗浄物に洗浄液を噴出しやすくなるからである。
洗浄用２流体ノズルの直管部９の長さは、その下限値は通常１０ｍｍ以上、好ましくは１５ｍｍ以上であり、上限値は通常４０ｍｍ以下程度、好ましくは３０ｍｍ以下である。本発明の洗浄用２流体ノズルを用いた場合、混合部５での気泡の破裂により洗浄液にパルスが発生するため、洗浄液が広がって噴出しやすい。しかし、上記範囲とすることにより、パルス成分をあまり低下させることなく、洗浄液の広がりを適切に抑制することができるため、被洗浄物を効果的に洗浄できる。
【００２１】
また、噴出口６と被洗浄物の距離は通常５ｃｍ以上、１５ｃｍ以下とするのが好ましい。最適な距離は加圧気体の圧力等に左右されるが、通常この範囲であれば、洗浄液を十分に加速させることができ、さらに洗浄液の広がりによる洗浄力の低下を抑えることができるからである。
本発明に用いる洗浄液は特に限定されず、例えば水、酸、アルカリ、有機溶剤などいずれも用いうるが、洗浄液は被洗浄物に付着している付着物に応じて選択するのが好ましい。また、洗浄液は複数の種類の液体を混合させて使用しても良く、特に本願発明では洗浄液中に気泡が含まれており、その気泡が被洗浄物と衝突した際の破裂によるバブリング効果が期待できるため、洗剤を混ぜておくと泡が立ちやすく、汚れが落ちやすくなるといった効果も期待することができる。
【００２２】
磁気記録媒体や光記録媒体などを洗浄する場合にはアルカリ系洗剤を含む洗浄液を用いるのが好ましい。アルカリ系洗剤の混合量は、例えば水１００％に対して１〜５％程度とすると、適度に泡がたち洗浄効果が増すため好ましい。
本発明に用いる加圧気体は空気、窒素など特に限定されないが、その取り扱いの容易さから空気を用いるのが好ましい。
【００２３】
洗浄用２流体ノズルの材質としては、一般的な洗浄ノズルに用いられるものを広く用いることができる。洗浄液として水を用いる際には、ＳＵＳ３１６やＳＵＳ３０４などのステンレス鋼を用いると錆が発生せずノズルの寿命を長くすることができ好ましい。また、ＰＴＦＥ（ポリテトラフルオロエチレン）などを用いると、ノズルが摩耗しても摩耗粉が発生しにくく、洗浄物を傷つけることなく好ましい。また、有機溶剤を洗浄液として用いる場合にはその耐性を期待することができる。
【００２４】
【実施例】
以下に実施例を示すが、本発明はその要旨を越えない限り、以下の実施例に限定されるものではない。
（実施例）
図１に示す洗浄用２流体ノズルを使用して洗浄力のテストを行った。使用した洗浄用２流体ノズルの各部の寸法は、気泡発生用加圧気体供給路１０の径は１ｍｍ、内筒部７の円錐形状の広がり角度ａは５０°、外筒部８内部の円錐形状の広がり角度ｂは６０°、内筒部の開口の径は２ｍｍ、噴出口の径は４ｍｍ、直管部の長さは２０ｍｍである。洗浄用２流体ノズルの材質としてはＰＴＦＥ（ポリテトラフルオロエチレン）を用いた。洗浄液としては水を用い、その圧力は１００ｋＰａで一定とした。加圧気体としては空気を用いた。
【００２５】
テスト開始直後より、洗浄用２流体ノズルから気泡の破裂する音が聞こえ、破裂音と共に洗浄液にパルスが発生していることが確認できた。気泡の破裂する音は圧力を上げるに従って聞こえなくなっていき、さらに洗浄液のパルスも目視では確認できなくなった。加圧気体の圧力が５００ｋＰａになったときのパルスの周波数は少なくとも６０Ｈｚ以上になっていたと考えられる。
【００２６】
洗浄力の評価は、台ばかりの垂直上方向１５ｃｍの位置に洗浄用２流体ノズルを設置し、台ばかりに向かって洗浄液を吹き付け、加圧気体の圧力を表―１のように２００ｋＰａから５００ｋＰａまで変化させつつ、その台ばかりの指示値の最大値を測定することにより行った。測定結果を表―１に示す。
（比較例）
図２に示すような、第二加圧気体供給口１３を持たない洗浄用２流体ノズルを用いて、実施例と同様に洗浄力のテスト及び洗浄力の評価を行った。テスト中に気泡の破裂する音は聞こえなかった。測定結果を表―１に示す。
【００２７】
【表１】

表―１から明らかなように、本発明の洗浄用２流体ノズルを用いた実施例の方が、従来の洗浄用２流体ノズルを用いた比較例に比べて、加圧気体の圧力が同じであっても台ばかりの指示値の最大値が高い。よって、本発明の洗浄用２流体ノズルによれば、加圧気体等の圧力を高くせずとも、洗浄力が向上できると推測される。
【００２８】
【発明の効果】
本発明の洗浄用２流体ノズル及び洗浄方法によれば、洗浄液中に小さな気泡（キャビテーション）を発生させることができるため、この気泡の破裂を利用した洗浄液のパルス効果及び気泡が付着物に衝突した際の破裂の衝撃により、洗浄用２流体ノズルの洗浄力を向上させることができる。よって、本発明によれば、従来のようにコンプレッサーの能力を上げるなどして、加圧気体等の圧力をあげることなく、ノズルを交換するだけで容易に洗浄力を向上させることができる。
【００２９】
また、本発明の洗浄方法によれば、通常より洗浄力を高くすることができるので、例えば磁気記録媒体や光記録媒体の製造ラインで用いると、欠陥を低減でき、優れた品質の磁気記録媒体や光記録媒体を提供することができる。
【図面の簡単な説明】
【図１】本発明の洗浄用２流体ノズルの一例を示す概略的な断面図である。
【図２】従来の洗浄用２流体ノズルの一例を示す概略的な断面図である。
【図３】従来の洗浄用２流体ノズルの他の一例を示す概略的な断面図である。
【符号の説明】
１洗浄液供給口
２加圧気体供給口
３洗浄液供給部
４加圧気体供給部
５混合部
６噴出口
７内筒部
８外筒部
９直管部
１０気泡発生用加圧気体供給路
１１気泡発生用加圧気体圧力調節部
１２第一加圧気体供給口
１３第二加圧気体供給口
１４加速部
１５混合部
１６加圧気体流入口
１７洗浄液流入口[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a two-fluid nozzle for cleaning and a cleaning method, in which a cleaning liquid is pressurized and ejected using a pressurized gas. More specifically, the present invention relates to a cleaning two-fluid nozzle that performs cleaning by generating bubbles (cavitation) in the cleaning liquid.
[0002]
[Prior art]
A cleaning two-fluid nozzle is widely used as a cleaning nozzle for removing deposits such as dust and dirt. FIG. 2 is an example of a structure of a two-fluid nozzle for cleaning that has been widely used conventionally. The main body of the cleaning two-fluid nozzle has a double cylindrical structure of an inner cylinder portion 7 and an outer cylinder portion 8. One end of the inner cylinder part 7 and the outer cylinder part 8 is tapered in a conical shape, an opening is provided at the tip of the inner cylinder part 7, and the outside of the opening is a mixture in which cleaning liquid and pressurized gas are mixed. Part 5. The distal end of the outer cylinder portion 8 that has passed through the mixing portion 5 is a straight tube portion 9, and a jet port 6 is provided at the distal end of the straight tube portion 9. The inside of the inner cylinder part 7 is a cleaning liquid supply part 3, and the cleaning liquid supply port 1 is provided at the other end of the inner cylinder part 7. Between the inner cylinder part 7 and the outer cylinder part 8 is a pressurized gas supply part 4, and the pressurized gas supply port 2 is provided in the outer cylinder part 8.
[0003]
A method of using the cleaning two-fluid nozzle according to the present invention will be described.
First, a hose or the like is connected to the cleaning liquid supply port 1 to supply the cleaning liquid to the cleaning two-fluid nozzle. The cleaning liquid is supplied from the cleaning liquid supply port 1 to the cleaning liquid supply unit 3. Further, pressurized gas having a pressure higher than that of the cleaning liquid is supplied from the pressurized gas supply port 2 to the two-fluid cleaning nozzle. The pressurized gas is supplied from the pressurized gas supply port 2 to the pressurized gas supply unit 4. The cleaning liquid and the pressurized gas supplied to the cleaning two-fluid nozzle are mixed in the mixing unit 5. Since the pressure of the pressurized gas is higher than that of the cleaning liquid, the cleaning liquid mixed with the pressurized gas is accelerated by the pressurized gas, and the speed is increased and the jet is ejected from the jet outlet 6 through the straight pipe portion 9 of the two-fluid nozzle for cleaning. To do. The cleaning liquid ejected from the cleaning two-fluid nozzle collides with the object to be cleaned, and removes the adhering substance adhering to the object to be cleaned.
[0004]
FIG. 3 shows another example of the structure of a two-fluid nozzle for cleaning that has been conventionally used.
The two-fluid nozzle for cleaning includes a mixing unit 15 and an acceleration unit 14, and the mixing unit 15 is provided with a pressurized gas inlet 16 and a cleaning liquid inlet 17.
A pressurized gas flows from the pressurized gas inlet 16 and a cleaning liquid flows from the cleaning liquid inlet 17 into the mixing unit 15. The injected pressurized gas and the cleaning liquid are mixed by the mixing unit 15 to form cleaning liquid droplets. The cleaning liquid droplets formed in the mixing unit 15 proceed to the acceleration unit 14 together with the pressurized gas, and the cleaning liquid droplets are accelerated by the pressurized gas and ejected. The droplets of the cleaning liquid ejected from the cleaning two-fluid nozzle collide with the object to be cleaned and remove the adhering substance adhering to the object to be cleaned (Patent Document 1).
[0005]
[Patent Document 1]
JP-A-10-156229 gazette
[Problems to be solved by the invention]
However, in the conventional two-fluid nozzle for cleaning as described above, lack of cleaning power sometimes becomes a problem. As described above, the conventional two-fluid nozzle for cleaning performs cleaning by accelerating the cleaning liquid using the pressure of the pressurized gas. Therefore, when the pressure of the pressurized gas is not sufficiently high, the cleaning liquid cannot be sufficiently accelerated, and the cleaning power is insufficient. In order to increase this cleaning power, it is sufficient to increase the pressure of the pressurized gas, but in order to increase the pressure of the pressurized gas, it is often necessary to take measures such as increasing the capacity of the compressor, and its cost becomes a problem. Come. In addition, when the pressure of the pressurized gas is increased, the cleaning two-fluid nozzle itself must have a high-pressure specification, which causes a problem that the manufacturing cost of the cleaning two-fluid nozzle increases.
[0007]
In order to solve the above problems, the present invention provides a cleaning two-fluid nozzle that improves the cleaning power without increasing the pressure of the pressurized gas or the like by mixing the pressurized gas into the cleaning liquid. And a cleaning method.
[0008]
[Means for Solving the Problems]
The gist of the present invention is that, in a two-fluid cleaning nozzle for removing a deposit adhered to an object to be cleaned, the cleaning liquid is pressurized and jetted from a jet outlet, and the cleaning nozzle includes a cleaning liquid and a pressurized gas. A mixing unit that mixes, a cleaning liquid supply unit that supplies a cleaning liquid to the mixing unit, a pressurized gas supply unit that supplies a pressurized gas to the mixing unit, and a pressurized gas that is supplied to the pressurized gas supply unit A first pressurized gas supply port, a cleaning liquid supply port for supplying a cleaning liquid to the cleaning liquid supply unit, and a second pressurized gas supply port for supplying the pressurized gas to the cleaning liquid supply unit. The two-fluid nozzle for cleaning is characterized by the following.
[0009]
Another gist of the present invention resides in a cleaning method using the two-fluid nozzle for cleaning.
According to the present invention, by supplying pressurized gas to the cleaning liquid supply unit, small bubbles (cavitation) can be generated in the cleaning liquid. And when this bubble bursts in a mixing part, it becomes easy to remove a deposit by generating a shock wave. Further, the bubbles are ruptured when the bubbles collide with the object to be cleaned, thereby facilitating removal of the deposits. Thereby, the cleaning power of the cleaning nozzle can be improved.
[0010]
The two-fluid nozzle for cleaning according to the present invention is suitable for use in the production line of precision products such as magnetic recording media and optical recording media where fine deposits are a problem due to its high cleaning ability. .
In addition, the pressurized gas in this invention means the gas of the pressure larger than atmospheric pressure in the usage place of the 2 fluid nozzle for washing | cleaning.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
A two-fluid nozzle for cleaning according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic view showing the structure of an embodiment of a two-fluid nozzle for cleaning according to the present invention.
As shown in FIG. 1, the cleaning two-fluid nozzle main body according to the present invention has a double cylindrical structure of an inner cylinder portion 7 and an outer cylinder portion 8. One end of the inner cylinder part 7 and the outer cylinder part 8 is tapered in a conical shape, and an opening is provided at the tip of the inner cylinder part 7, and the outside of the opening is mixed with cleaning liquid and pressurized gas. It is the mixing part 5 to do. The distal end of the outer cylinder portion 8 that has passed through the mixing portion 5 is a straight tube portion 9, and a jet port 6 is provided at the distal end of the straight tube portion 9. The inside of the inner cylinder part 7 is a cleaning liquid supply part 3, and the cleaning liquid supply port 1 is provided at the other end of the inner cylinder part 7. Between the inner cylinder part 7 and the outer cylinder part 8 is a pressurized gas supply part 4, and a first pressurized gas supply port 12 is provided in the outer cylinder part 8. The pressurized gas supply unit 4 is connected to the cleaning liquid supply unit 3 through the second pressurized gas supply port 13 via the bubble generation pressurized gas supply path 10, and is used for pressure generation as a pressure adjusting means. A gas pressure adjusting unit 11 is provided.
[0012]
Next, a cleaning method using the cleaning two-fluid nozzle according to the present invention will be described.
A hose or the like is connected to the cleaning liquid supply port 1 to supply the cleaning liquid to the cleaning two-fluid nozzle. The cleaning liquid is supplied from the cleaning liquid supply port 1 to the cleaning liquid supply unit 3. Further, pressurized gas having a pressure higher than that of the cleaning liquid is supplied to the nozzle from the first pressurized gas supply port 12. The pressurized gas is supplied from the first pressurized gas supply port 12 to the pressurized gas supply unit 4. Part of the pressurized gas supplied to the pressurized gas supply unit 4 passes through the bubble generating pressurized gas supply path 10 via the second pressurized gas supply port 13 and is supplied to the cleaning liquid supply unit 3. . The pressurized gas supplied to the cleaning liquid becomes small bubbles of about sub-μm and exists in the cleaning liquid. Air bubbles present in the cleaning liquid move to the mixing unit 5 together with the cleaning liquid. The bubbles that have reached the mixing section 5 rapidly expand with a decrease in pressure, and some of the bubbles burst at the mixing section 5. When the bubbles burst, a shock wave (pulse) is generated in the cleaning liquid. The cleaning liquid in which the pulse is generated is mixed with the pressurized gas by the mixing unit 5. The cleaning liquid is accelerated by the pressurized gas, and its speed is increased and ejected from the nozzle outlet 6. The cleaning liquid containing bubbles ejected from the nozzle collides with the object to be cleaned, and the bubbles in the cleaning liquid burst when colliding. In addition, the size of bubbles generated in the cleaning liquid is usually about 0.01 μm to 10 μm.
[0013]
The pulse of the cleaning liquid generated when the bubbles burst in the mixing unit 5 indicates a state in which the cleaning liquid jet pressure is repeatedly high and low. The pressure in a state where the ejection pressure of the cleaning liquid generated by the burst of bubbles is higher than the ejection pressure of the cleaning liquid in a state where the bubbles do not burst in the mixing unit 5 and do not have a pulse. As a result, the ejection pressure of the cleaning liquid can be increased without increasing the pressure of the pressurized gas, and the cleaning power is improved. Further, the bubbles blown out in the state of being contained in the cleaning liquid without being ruptured by the mixing unit 5 are ruptured when colliding with the object to be cleaned. Due to the impact generated when the bubbles burst, the adhered matter easily separates from the object to be cleaned. This improves the cleaning power.
[0014]
A feature of the present invention is that it has a second pressurized gas supply port 13 for supplying pressurized gas to the cleaning liquid supply unit 3. By having the second pressurized gas supply port 13, it is possible to improve the cleaning power due to the pulse of the cleaning liquid and the burst of bubbles as described above.
A bubble generating pressurized gas pressure adjusting unit 11 as a pressure adjusting means is provided in a bubble generating pressurized gas supply path 10 following the second pressurized gas supplying port 13 for supplying pressurized gas to the cleaning liquid supplying unit 3. It is preferable to provide a structure in which the pressure of the pressurized gas supplied to the cleaning liquid supply unit 3 can be adjusted. By adjusting the pressure of the pressurized gas supplied to the cleaning liquid supply unit 3, the amount and size of bubbles generated in the cleaning liquid can be adjusted, so the frequency of pulses generated in the cleaning liquid and the nozzles ejected from the nozzle The amount of bubbles in the subsequent cleaning liquid can be controlled. That is, it is possible to adjust the strength of the cleaning power. The mechanism of the bubble generating pressurized gas pressure adjusting unit 11 that is the pressure adjusting means may be any mechanism as long as it can adjust the pressure, but the operation is easy and the structure is simple. Therefore, the needle valve is structured to be movable by a screw type mechanism, and the needle valve is moved to change the area of the gap between the bubble generating pressurized gas supply path 10 and the needle valve, and supply it to the cleaning liquid supply unit 3. A mechanism capable of adjusting the pressure of the pressurized gas is preferable.
[0015]
In FIG. 1, only one second pressurized gas supply port 13 for supplying pressurized gas to the cleaning liquid supply unit 3 and one bubble generating pressurized gas supply path 10 are provided. There is no limitation, and two or more of each may be provided. Moreover, as long as pressurized gas can flow in, the shape may be any shape.
The frequency of the pulses generated in the cleaning liquid is usually 20 Hz or more, preferably 50 Hz or more. If the frequency is too low, the impact due to the pulse may not be effectively transmitted to the deposit. If it is this range, the impact by a pulse can be effectively transmitted to a deposit | attachment, and the improvement of a cleaning power can be aimed at. However, the frequency is usually 200 Hz or less, preferably 150 Hz or less. If the frequency is too high, the impact of the pulse on the deposit is reduced. If it is this range, the improvement of the cleaning power by the pulse effect appropriate for the cleaning liquid can be expected.
[0016]
The pressure of the pressurized gas supplied to the cleaning liquid supply unit 3 must be higher than the pressure of the cleaning liquid. This is because if the pressure is lower than that of the cleaning liquid, the pressurized gas cannot flow into the cleaning liquid, so that bubbles are not generated. The difference between the pressure of the pressurized gas supplied to the cleaning liquid supply unit 3 and the pressure of the cleaning liquid is usually 200 kPa or more, preferably 300 kPa or more. If the pressure difference between the pressure of the pressurized gas and the cleaning liquid is within this range, the pressurized gas will flow appropriately into the cleaning liquid, so that fine bubbles can be generated appropriately, and the surface can be soft or fine. It is possible to effectively clean even the attached matter. In addition, the difference between the pressure of the pressurized gas supplied to the cleaning liquid supply unit 3 and the pressure of the cleaning liquid is usually 1200 kPa or less, and preferably 1000 kPa or less. If the pressure difference between the pressure of the pressurized gas and the cleaning liquid is equal to or smaller than this value, it is possible to prevent excessive inflow of the pressurized gas and generate an appropriate amount of bubbles.
[0017]
As described above, the cleaning two-fluid nozzle structure of the present invention is configured such that the cleaning liquid supply unit 3 and the pressurized gas supply unit 4 are connected to the bubble generating pressurized gas supply path 10 via the second pressurized gas supply port 13. It is preferable to have a structure that can be connected. By adopting such a structure, it is possible to supply pressurized gas simultaneously to the cleaning liquid supply unit 3 simply by supplying pressurized gas from the first pressurized gas supply port 12. The structure can be simplified.
[0018]
However, even if the pressurized gas supply line is provided in each of the first pressurized gas supply port 12 and the second pressurized gas supply port 13 to supply the pressurized gas into the cleaning liquid, the effect of the present invention is naturally obtained. I can expect. In this case, it is preferable that pressure adjusting means such as a pressure reducing valve is provided in the pressurized gas supply line of the second pressurized gas supply port 13 so that the pressure of the supplied pressurized gas can be adjusted.
[0019]
The lower limit of the diameter of the pressurized gas supply passage 10 for generating bubbles is usually 0.3 mm or more, preferably 0.5 mm or more, and the upper limit is usually 2.0 mm or less, preferably 1.5 mm or less. is there. If it is this range, since a suitable quantity of pressurized gas can be supplied, a bubble can be stably generated in a washing | cleaning liquid.
The lower limit value of the opening diameter of the inner cylinder part of the two-fluid nozzle for cleaning is usually 1.0 mm or more, preferably 1.5 mm or more, and the upper limit value is 3.0 mm or less, preferably 2.5 mm or less. This is because a cleaning liquid containing an appropriate amount of bubbles can be supplied to the mixing unit 5 within this range, and it becomes easy to effectively generate pulses due to the burst of bubbles.
[0020]
The lower limit value of the diameter of the jet of the two-fluid nozzle for cleaning is usually 2.0 mm or more, preferably 2.5 mm or more, and the upper limit value is 6.0 mm or less, preferably 5.5 mm or less. This is because, within this range, the cleaning liquid can be easily ejected onto the object to be cleaned with high accuracy while suppressing the spread of the cleaning liquid without impairing the momentum of the cleaning liquid.
The length of the straight pipe part 9 of the two-fluid nozzle for cleaning has a lower limit of usually 10 mm or more, preferably 15 mm or more, and an upper limit of usually about 40 mm or less, preferably 30 mm or less. When the two-fluid nozzle for cleaning according to the present invention is used, pulses are generated in the cleaning liquid due to the bursting of bubbles in the mixing section 5, so that the cleaning liquid spreads and is easily ejected. However, by setting it within the above range, the spread of the cleaning liquid can be appropriately suppressed without significantly reducing the pulse component, so that the object to be cleaned can be effectively cleaned.
[0021]
Moreover, it is preferable that the distance of the jet nozzle 6 and a to-be-cleaned object shall normally be 5 cm or more and 15 cm or less. This is because the optimum distance depends on the pressure of the pressurized gas, etc., but usually within this range, the cleaning liquid can be sufficiently accelerated, and further the reduction in cleaning power due to the spread of the cleaning liquid can be suppressed. .
The cleaning liquid used in the present invention is not particularly limited, and for example, any of water, acid, alkali, organic solvent, and the like can be used. However, the cleaning liquid is preferably selected according to the deposit attached to the object to be cleaned. Further, the cleaning liquid may be used by mixing a plurality of types of liquids. In particular, in the present invention, bubbles are included in the cleaning liquid, and a bubbling effect due to bursting when the bubbles collide with an object to be cleaned is expected. Therefore, it can be expected that if detergent is mixed, bubbles are easily formed and dirt is easily removed.
[0022]
When cleaning a magnetic recording medium or an optical recording medium, it is preferable to use a cleaning liquid containing an alkaline detergent. When the amount of the alkaline detergent mixed is, for example, about 1 to 5% with respect to 100% of water, it is preferable because the foaming effect is appropriately increased and the cleaning effect is increased.
The pressurized gas used in the present invention is not particularly limited, such as air or nitrogen, but it is preferable to use air because of its ease of handling.
[0023]
As a material of the two-fluid nozzle for cleaning, those used for general cleaning nozzles can be widely used. When water is used as the cleaning liquid, it is preferable to use stainless steel such as SUS316 or SUS304 because rust does not occur and the life of the nozzle can be extended. Further, when PTFE (polytetrafluoroethylene) or the like is used, even if the nozzle is worn, abrasion powder is hardly generated, which is preferable without damaging the cleaning object. In addition, when an organic solvent is used as the cleaning liquid, its resistance can be expected.
[0024]
【Example】
Examples are shown below, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded.
(Example)
The cleaning power test was performed using the two-fluid nozzle for cleaning shown in FIG. The dimensions of each part of the used cleaning two-fluid nozzle are as follows. The diameter of the pressurized gas supply passage 10 for generating bubbles is 1 mm, the conical shape expansion angle a of the inner cylinder portion 7 is 50 °, and the conical shape inside the outer cylinder portion 8. The spread angle b is 60 °, the diameter of the opening of the inner cylinder part is 2 mm, the diameter of the jet port is 4 mm, and the length of the straight pipe part is 20 mm. PTFE (polytetrafluoroethylene) was used as a material for the two-fluid nozzle for cleaning. Water was used as the cleaning liquid, and the pressure was constant at 100 kPa. Air was used as the pressurized gas.
[0025]
Immediately after the start of the test, the sound of bursting bubbles was heard from the cleaning two-fluid nozzle, and it was confirmed that a pulse was generated in the cleaning liquid together with the bursting sound. The sound of the bursting of bubbles disappeared as the pressure was increased, and the pulse of the cleaning liquid could not be confirmed visually. It is considered that the frequency of the pulse when the pressure of the pressurized gas was 500 kPa was at least 60 Hz or more.
[0026]
The cleaning power is evaluated by installing a two-fluid nozzle for cleaning at a position 15 cm vertically upward of the platform, spraying the cleaning liquid toward the platform, and increasing the pressure of the pressurized gas from 200 kPa to 500 kPa as shown in Table-1. While changing, it was performed by measuring the maximum value of the indicated value on the stand alone. The measurement results are shown in Table-1.
(Comparative example)
Using a cleaning two-fluid nozzle that does not have the second pressurized gas supply port 13 as shown in FIG. 2, the cleaning power test and the cleaning power evaluation were performed in the same manner as in the example. During the test, no bubble burst was heard. The measurement results are shown in Table-1.
[0027]
[Table 1]

As is clear from Table-1, the pressure of the pressurized gas is the same in the example using the cleaning two-fluid nozzle of the present invention compared to the comparative example using the conventional cleaning two-fluid nozzle. Even if it is, the maximum value of the indicator value is high. Therefore, according to the cleaning two-fluid nozzle of the present invention, it is estimated that the cleaning power can be improved without increasing the pressure of the pressurized gas or the like.
[0028]
【The invention's effect】
According to the cleaning two-fluid nozzle and the cleaning method of the present invention, it is possible to generate small bubbles (cavitation) in the cleaning liquid. Therefore, the pulse effect of the cleaning liquid using the burst of the bubbles and the bubbles collide with the deposit. The cleaning power of the cleaning two-fluid nozzle can be improved by the impact of the bursting. Therefore, according to the present invention, it is possible to easily improve the detergency by simply replacing the nozzle without increasing the pressure of the pressurized gas or the like by increasing the capacity of the compressor as in the prior art.
[0029]
Further, according to the cleaning method of the present invention, the cleaning power can be made higher than usual, so that, for example, when used in a production line of a magnetic recording medium or an optical recording medium, defects can be reduced, and an excellent quality magnetic recording medium. And an optical recording medium can be provided.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view showing an example of a two-fluid nozzle for cleaning according to the present invention.
FIG. 2 is a schematic cross-sectional view showing an example of a conventional cleaning two-fluid nozzle.
FIG. 3 is a schematic cross-sectional view showing another example of a conventional cleaning two-fluid nozzle.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cleaning liquid supply port 2 Pressurized gas supply port 3 Cleaning liquid supply part 4 Pressurized gas supply part 5 Mixing part 6 Outlet 7 Inner cylinder part 8 Outer cylinder part 9 Straight pipe part 10 Pressurized gas supply path 11 for bubble generation Bubble generation Pressurized gas pressure control unit 12 First pressurized gas supply port 13 Second pressurized gas supply port 14 Accelerating unit 15 Mixing unit 16 Pressurized gas inlet 17 Cleaning liquid inlet

Claims

In the two-fluid nozzle for cleaning that ejects the cleaning liquid from the jet outlet by pressurizing with a pressurized gas, and removing the deposits adhered to the object to be cleaned.
The cleaning nozzle is
A mixing section for mixing the cleaning liquid and the pressurized gas;
A cleaning liquid supply section for supplying a cleaning liquid to the mixing section;
A pressurized gas supply unit for supplying pressurized gas to the mixing unit;
A first pressurized gas supply port for supplying pressurized gas to the pressurized gas supply unit;
A cleaning liquid supply port for supplying the cleaning liquid to the cleaning liquid supply unit;
Have
Furthermore, it has a 2nd pressurized gas supply port which supplies this pressurized gas to this washing | cleaning liquid supply part, The 2 fluid nozzle for washing | cleaning characterized by the above-mentioned.

The two-fluid nozzle for cleaning according to claim 1, further comprising pressure adjusting means for adjusting the pressure of the pressurized gas supplied to the cleaning liquid supply unit.

The two-fluid nozzle for cleaning according to claim 1 or 2, wherein pressurized gas is supplied from the pressurized gas supply unit to the cleaning liquid supply unit via a second pressurized gas supply port.

A cleaning method, comprising: cleaning an object to be cleaned using the cleaning two-fluid nozzle according to any one of claims 1 to 3.