JP4016369B2

JP4016369B2 - Multicolor electrostatic coating color changing device for conductive paint

Info

Publication number: JP4016369B2
Application number: JP07629099A
Authority: JP
Inventors: 茂小林; 秀隆塚本; 信男池田
Original assignee: ノードソン株式会社
Priority date: 1999-02-15
Filing date: 1999-02-15
Publication date: 2007-12-05
Anticipated expiration: 2019-02-15
Also published as: AU3233500A; WO2000047333A1; JP2000233142A

Description

【０００１】
【発明の属する技術分野】
本発明は、高電圧が印加される静電塗装用噴出ガンを用い、水性塗料などの導電性塗料による、多色静電塗装の色替え装置に関するもので、更に詳細には印加される高電圧に影響されることなく、塗装中の系統以外の系のメンテナンスや色替え作業が容易行える、導電性塗料の多色静電塗装色替え装置に関するものである。
【０００２】
【従来の技術】
静電塗装法は、塗料の噴出ガンに設けたコロナピンに高電圧（一般には８０〜１２５ＫＶ）を印加し、噴出ガンから噴出する塗料を高電位に静電帯電させ、アースされた被塗物の表面に塗布する技術である。従って塗料が水やメタノール等の導電性溶剤をベースとする導電性塗料を用いる場合、導電性塗料によって噴出ガンから塗料供給ラインを介して塗料タンクに至るまで導電路が形成されてしまう。従って塗料タンクやポンプなどの塗料供給系を接地から絶縁しておかないと、高電圧が塗料供給系を通してアースしてしまうので、噴出ガンに設けたコロナピンに高電圧を印加することが出来ない。
【０００３】
またこのような装置にあっては、噴出ガンから塗料供給系にいたるすべての機器に高電位の静電気が蓄積される。従って非常に大きな放電エネルギーが蓄積された塗料供給系の機器に過って作業者が接触すると大変危険である。従って運転中に塗料タンクへ塗料を補給することも出来ない。また多色塗装色替え装置においても、複数色の塗料供給系が切り換えバルブ等を介して直接接続されるような構成にしておくと、実際に使用中の塗料供給系以外の他色の塗料供給系にも切り換えバルブを介して静電気が蓄積されることになり、実際に使用していない他色の塗料タンクにも塗料を補給することも出来ず、危険の範囲が増大する。
【０００４】
このような多色塗装色替えの問題点を軽減する方法として、特開平４−２００６６３号及び特開平４−２００６６４号公報に示される技術が提案されている。まず特開平４−２００６６３号公報に示される技術について述べると、同公報には、高電圧が印加された静電塗装機で導電性塗料を塗装する導電性塗料の静電塗装装置において、塗料流入口と、その塗料流入口から導入された所要量の導電性塗料が静電塗装機の塗料吐出量に応じた所定の流量で圧し出される塗料吐出口とを有した複数のポンプが、電気的絶縁状態で設置され、当該各ポンプの塗料流入口に対して、夫々に洗浄空気供給バルブと洗浄液供給バルブを具備する各色替バルブ装置に接続された各塗料供給配管が係脱自在に連結されると共に、当該各ポンプの塗料吐出口が、その塗料吐出口を静電塗装機側の流出路と排液タンク側の流出路に切換バルブに連結され、前記排液タンク側の流出路に対して、排液タンクに接続した各排液配管が係脱自在に連結されるように成された導電性塗料の静電塗装技術が開示されている。
【０００５】
また特開平４−２００６６４号公報に示される技術について述べると、同公報には、高電圧が印加された静電塗装機で導電性塗料を塗装する導電性塗料の静電塗装装置において、内部に貯留された所要量の導電性塗料を空気圧で圧し出して静電塗装機に定量供給する複数の塗料圧送タンクと、内部に貯留された所要量の洗浄液を空気圧で圧し出して静電塗装機に供給する洗浄液圧送タンクが夫々電気的絶縁状態で設置されて、前記静電塗装機に連なるマニホールドに並設した各色替バルブと洗浄液供給バルブに接続されると共に、前記各塗料圧送タンクと前記洗浄液圧送タンクに夫々塗料補給口と洗浄液補給口が設けられ、当該各塗料補給口と洗浄液補給口に対して、夫々各塗料供給源から各色の導電性塗料を供給する供給配管と洗浄液供給配管が係脱自在に連結されるように成された導電性塗料の静電塗装技術が開示されている。
【０００６】
【発明が解決しようとする課題】
前記した従来技術、すなわち特開平４−２００６６３号及び特開平４−２００６６４号公報に示される技術においては、次のような問題があった。まず特開平４−２００６６３号について述べると、回路が比較的複雑であり、従って操作も比較的面倒であること。各塗料供給系ごとに塗料の供給系と塗料排液系の二つの切り離し機構が必要であること。また公報や図では明らかではないが、使用中の系すなわち静電塗装機に接続された系にあっては色替バルブ装置（９Ａ，９Ｂ，９Ｃ）の色替バルブ（ＣＶ_１〜ＣＶ_３）にそれぞれ継続される複数色の塗料供給系、すなわちポンプや塗料タンク等に至までが導電性の塗料を介して導電路が形成されてしまい、高電位の危険にさらされるため、いずれの色の塗料も補給が出来ない。従って塗料を補給する場合は、一旦塗装作業を停止して、高電圧を遮断開放してから塗料を補給しなければならない等の問題がある。
【０００７】
また特開平４−２００６６４号について述べると、この技術においても塗装中は、複数色の塗料圧送タンク（１Ａ，２Ｂ，２Ｃ）及び洗浄液圧送タンク（３）までが導電性の塗料あるいは洗浄液を介して導電路が形成されてしまい、高電位の危険にさらされるため、いずれの塗装色塗料も補給が出来ない。従って塗料を補給する場合は、一旦塗装作業を停止して、高電圧を遮断開放した状態で塗料圧送タンクへ塗料を補給しなければならない等の問題がある。
【０００８】
本願発明は、上記した問題点に鑑みてなされたものであり、導電性塗料の多色静電塗装装置において比較的に装置構成や操作が簡単、単純で、複数の塗装色による塗装作業において、使用中の塗装色以外の塗装色供給系は、高電圧のチャージ回路から完全に切り離して高電圧の影響を受けないようにすることにより、塗料の補給やメンテナンス等の作業が塗装中にも行え、更に色替えの容易な導電性塗料の多色静電塗装色替え装置を提供することを目的とするものである。
【０００９】
【課題を解決するための手段】
前記した課題を解決するために、本願発明では次のような方法とした。すなわち、導電性塗料の多色静電塗装色替え装置において、ガイドレール上を移動可能に設けられた管継手ａと、該管継手ａと管路で接続された静電噴出ガンとを設けると共に、更に液槽と、ポンプと、前記管継手ａと係脱自在に係合する管継手ｂとを、管路で結んだ塗料供給循環回路を複数系統設け、前記管継手ａと複数系統の塗料供給循環回路の管継手ｂとを、選択的に係脱できるようにし、前記管継手ａと前記複数系統の塗料供給循環回路の管継手ｂとが選択的に係合されたとき、前記管継手ａと係合された前記管継手ｂの塗料供給循環回路はアースが絶たれて絶縁され、前記管継手ａと係合が解かれた管継手ｂの塗料供給循環回路は前記管継手ａ側の高電圧電導路から切り離されると共にアースされる構成したことを特徴とする導電性塗料の多色静電塗装色替え装置とした。
【００１０】
【発明の実施の形態】
次に本発明の実施の形態を説明する。本発明では、先ず複数系統の塗料供給循環回路、すなわち液槽と、ポンプと、管継手ｂとを、管路で結んだ塗料供給循環回路は、それぞれ独立して起動・停止等の操作が可能であり、またガイドレール上を移動可能に設けられた管継手ａと静電噴出ガンとは、ワンウエイの管路で接続されている。従って管継手ａに係合中の管継手ｂに係る塗料供給循環回路は、導電性の塗料によって静電噴出ガンに印加される高電圧の影響を受けるが、それ以外の塗料供給循環回路は、管継手ａと管継手ｂとの間で導電路が完全に遮断されることになり、高電圧の影響は受けない。従って塗装作業中であっても使用していない塗料供給循環回路には、何ら危険をおかすことなく塗料の補充やメンテナンスを行うことが出来る。
【００１１】
また色替えを行う場合、アースされた液槽の一つ（例えば液槽Ｄ）に洗浄液を充填しておき、Ａ色からＢ色に移る間に洗浄液を充填した液槽（Ｄ）の循環回路の管継手ｂと管継手ａとを係合すれば、管継手ａから管路で接続された静電噴出ガンに至る流路系がアースされると共に洗浄液で洗浄されるので混色もなく、色替え作業を容易に行うことができる。
【００１２】
【実施例】
以下本発明の導電性塗料の多色静電塗装色替え装置の実施例を、図を用いて具体的に説明する。図１は本発明による導電性塗料の多色静電塗装色替え装置の実施例の構成を示す正面概略図であり、図２は図１の側面概略図を示す。
【００１３】
図において符号１は架台あるいは壁面に固定されたガイドレールであり、２はガイドレール１上を移動可能に設けた管継手ａを示し、該管継手ａ２はアクチュエータ３によってガイドレール１上をを移動可能する。なおアクチュエータ３として本実施例では流体圧作動シリンダ機構を用いたが、該アクチュエータを電動式等の他の公知の方式で構成することもできる。４は内部に弁機構を持つ静電噴出ガンで、該静電噴出ガン４は高電圧電源５とケーブル６で結ばれ、静電噴出ガン４のコロナピンに高電圧（８０〜１２５ＫＶ）が印加される。また前記管継手ａ２と静電噴出ガン４とは管路７で結ばれる。なお管路７と管継手ａ２とを接続するに当たっては、管継手ａ２が移動するので、その移動に支障ないように構成することが必要であり、そのためにフレキシブルホース等を介在させるのが簡便な方法といえる。
【００１４】
また本実施例では静電噴出ガン４を２個設けたものを例示したが、静電噴出ガン４は２個に限定されるものではなく、被塗物の形状や大きさ等の条件によって所望の数だけ設ければよい。その際、静電噴出ガン４を複数個設ける場合には、それぞれの静電噴出ガン４からの塗料噴出量のバランスを調整することができるようにするため、各々に流量調整弁８を設けるのが望ましい。９はダンプバルブであり、１０は廃液受けで、該ダンプバルブ９及び廃液受け１０は、管路７内を清掃する際に使用される。更に図示していないが外部回収容器（ドラム缶等）に廃液を回収するばあいは、ダンプシャトルを設け外部回収容器とシステム系とを完全に電気的に絶縁させるとよい。
【００１５】
１１は塗料用の液槽（その内１個は洗浄液用として使用）であり、１２は液槽１１上に配置されたポンプを示す。１３は管継手ｂであり、該管継手ｂ１３は前記の管継手ａ２と、おす・めすの関係にあり係脱自在の構造をしている。なお管継手ａ２及び管継手ｂ１３には、係合されたときにのみ互いに液路が連通し、離脱したときには自動的に液路を閉じて液漏れを起こさない構造の逆止弁機構が内装されている。管継手ｂ１３は、係合・離脱操作を行うためのアクチュエータ１４のロットの先端と間に電気的な絶縁材１５を介在させて接続される。該アクチュエータ１４として、本実施例では流体圧作動シリンダ機構を用いた。また管継手ｂ１３は、管継手ａ２と離脱する下降点でアース線２３によって自動的にアースされる構成としている。また１６は圧力調整弁、２４はサーキュレーションバルブを示す。
【００１６】
そしてこれらの機器すなわち液槽１１、ポンプ１２、管継手ｂ１３、圧力調整弁１６及びサーキュレーションバルブ２４は、管路１７及び管路１８で結ばれ、塗料供給循環回路を形成する。すなわち液槽１１に貯留された導電性の液体塗料は、ポンプ１２によって汲み上げられ、管路１７から管継手ｂ１３に至り、管路１８、圧力調整弁１６及びサーキュレーションバルブ２４を通って再びポンプ１２の吸引側へ又は一部は液槽１１に戻る。その際塗料供給循環回路内の圧力は圧力調整弁１６によって所定の圧力に維持される。
【００１７】
管継手ｂ１３と接続される管路１７及び管路１８は、管継手ｂ１３が上下移動するので、その移動に支障のないように構成することが必要であり、そのためにフレキシブルホース等を介在させるのが簡便な方法といえる。１９は液槽１１を電気的に絶縁するための絶縁材である。また塗料供給循環回路は、管継手ａ２と管継手ｂ１３とが切り離された場合にも高電位の静電気が帯電残留する恐れがあり、液槽１１にはメンテナンス時に塗料供給循環回路内に帯電残留する静電気を接地して開放するための継電器２０と接地回路２１とが接続され、先に述べたアース線２３と共働して２重の安全機構となっている。２２は接地された被塗物を示す。
【００１８】
なお本実施例では、液槽１１、ポンプ１２、管継手ｂ１３、圧力調整弁１６及びサーキュレーションバルブ２４を、管路１７及び管路１８で結んだ塗料供給循環回路を便宜上３系統設けたものを図に例示したが、これに限定されるものでなく、必要とされる塗装色の数に応じた任意の系統数を設ければよい。
【００１９】
次に上記のように構成された静電塗装色替え装置の作用を説明する。まず液槽１１にそれぞれ異なった色の導電性塗料Ａ，Ｂ，Ｃを充填する。なお色替え時の塗料の流路を洗浄するため、便宜的にＤには洗浄液を充填するものとする。以下ここでは便宜上図１に示す塗料Ａを塗布する場合を代表例として説明するが、他の色を選択する場合も同様の操作になる。アクチュエータ３を操作して管継手ａ２を目的の色（図１のＡ色）の塗料供給循環回路の管継手ｂ１３と係合する位置に設定し、更にアクチュエータ１４を操作して管継手ａ２と管継手ｂ１３とを係合させる。そして高電圧電源５起動させ、静電噴出ガン４のコロナピンに高電圧を印加しておく。このときダンプバルブ９は閉じておく。
【００２０】
次に塗装色Ａのポンプ１２を起動すると液槽１１に貯留された導電性の液体塗料Ａは、ポンプ１２によって汲み上げられ、管路１７から管継手ｂ１３に至り、管路１８、圧力調整弁１６及びサーキュレーションバルブ２４を通って再びポンプ１２の吸引側あるいは液槽１１に戻る塗料供給循環回路内を循環すると共に、所定の圧力に維持されている塗料Ａは管継手ｂ１３から管継手ａ２を介し、管路７、流量調整弁８を通って静電噴出ガン４に至る。そして、静電噴出ガン４の内部に組み込まれた弁機構を開くと静電噴出ガン４のノズルから塗装色Ａが噴出し、アースされた被塗物２２の表面に塗布される。
【００２１】
このとき静電噴出ガン４に印加される高電圧は、導電性の塗料Ａを介して導電路が形成される塗料Ａ系統の塗料供給循環回路のすべての機器に及ぶことになる。従って導電路が形成されるすべての機器は絶縁状態に維持する必要がある。また図示していないが、作業者が過ってこれらの機器に触れることのないように、防護柵等で隔離することも必要である。すべての機器を絶縁状態に維持するために図１では、継電器２０を開状態に維持した接地回路２１、アクチュエータ１４が上昇することによりアース線２３からの切り離し、液槽１１に設けた絶縁材１９、によって系全体を絶縁状態に維持している。そして塗装色Ａで塗装中は、塗装色Ａ以外の塗装色Ｂ、塗装色Ｃ及び洗浄液Ｄの供給循環回路は管継手ｂ１３部分で高電圧電導路から完全に切り離されると共に、アース線２３及び閉じた継電器２０と接地回路２１によってアースされるので、高電圧の影響を受けない。
【００２２】
次に色替え作業の手順を説明する。先ず前色と後色との混色を避けるため、管継手ａ、管路７、流量調整弁８及び静電噴出ガン４を洗浄してやる必要がある。洗浄作業には特に高電圧の印加は必要ないので、洗浄作業に入る前に高電圧電源は遮断しておく。次にアクチュエータ１４を操作して管継手ａ２と管継手ｂ１３とを離脱させる。この時切り離された管継手ａ２及び管継手ｂ１３には、液漏れ防止の逆止弁機構が内装されているので液漏れは起きない。
【００２３】
次にアクチュエータ３を操作して管継手ａ２を、洗浄液が充填されたＤの洗浄液供給循環回路に接続された管継手ｂ１３と係合する位置に移動させる。そして、洗浄液供給循環回路Ｄのアクチュエータ１４を操作して管継手ｂ１３と管継手ａ２とを係合させる。そしてダンプバルブ９を開き、洗浄液Ｄのホンプ１２を起動すると、管路７内に残留した塗料Ａは洗浄液Ｄによって廃液受け１０内に押し出されて管路７内が洗浄される。管路７内の洗浄が済んだらダンプバルブ９を閉じて、静電噴出ガン４の内部に組み込まれた弁機構を開くと、流量調整弁８と静電噴出ガン４が洗浄される。流量調整弁８と静電噴出ガン４の洗浄が済んだら、静電噴出ガン４の内部に組み込まれた弁機構を閉じて洗浄作業は終了する。
【００２４】
次に洗浄液Ｄの供給循環回路と係合していた管継手ａ２と管継手ｂ１３とを切り離し、管継手ａ２を移動させて塗装色Ｂの塗料供給循環回路の管継手ｂ１３とを係合させ、塗料Ｂのポンプ１２を起動することにより、静電噴出ガン４へ塗料Ｂを供給することにより塗装色Ａから塗装色Ｂへの色替えが完了する。そして静電噴出ガン４に高電圧を印加して静電噴出ガン４の内部の弁機構を開くと被塗物２２に塗装色Ｂが塗布される。
【００２５】
このように塗料供給系を管継手ｂ１３を含む循環回路に構成することにより、管路の係脱用の管継手部は１個所で済ませることができ、従来技術に比べれば至って簡単である。また選択使用中の塗料供給循環回路以外、すなわち管継手ａ２と管継手ｂ１３とが係合中の塗料供給循環回路以外のものは、高電圧電源と管継手ｂ１３部分で完全に切り離されてアースされているので、運転中においても高電圧に影響されることなく塗料を補充したり、保守等のメンテナンス作業を行うことができる。ただし、管継手ｂ１３の切り離し前の時点の静電気が蓄積残留している恐れがあるので、メンテナンス作業に入る前に、継電器２０を閉状態にして、残留する静電気を接地回路２１を通して開放してやることが必要である。
【００２６】
【発明の効果】
以上説明したように、本願発明の導電性塗料の多色静電塗装色替え装置によれば、従来技術に比べて、比較的に装置構成や操作が簡単、単純で、複数の塗装色による塗装作業において、使用中の塗装色以外の塗装色供給系は、高電圧のチャージ回路から完全に切り離して高電圧の影響を受けないように構成されており、塗料の補給やメンテナンス等の作業が塗装中にも行え、更に色替え作業の容易な導電性塗料の多色静電塗装色替え装置を提供することができる。
【図面の簡単な説明】
【図１】本発明の実施例の構成を示す正面概略図。
【図２】図１の側面概略図。
【符号の説明】
１…ガイドレール、２…管継手ａ、３…アクチュエータ、４…静電噴出ガン、１１…液槽、１２…ポンプ、１３…管継手ｂ、１４…アクチュエータ、１６…圧力調整弁、２２…被塗物。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a color changing device for multi-color electrostatic coating using a spray gun for electrostatic coating to which a high voltage is applied and using a conductive coating such as a water-based coating. The present invention relates to a multicolor electrostatic coating color changing device for conductive paints that can easily perform maintenance and color change work for systems other than the system being painted.
[0002]
[Prior art]
In the electrostatic coating method, a high voltage (generally 80 to 125 KV) is applied to a corona pin provided in a paint spray gun, the paint sprayed from the spray gun is electrostatically charged to a high potential, and the grounded workpiece is coated. It is a technique to apply to the surface. Accordingly, when a conductive paint based on a conductive solvent such as water or methanol is used as the paint, a conductive path is formed by the conductive paint from the spray gun to the paint tank via the paint supply line. Therefore, unless the paint supply system such as the paint tank or the pump is insulated from the ground, the high voltage is grounded through the paint supply system, and therefore it is not possible to apply a high voltage to the corona pin provided in the ejection gun.
[0003]
Moreover, in such an apparatus, high potential static electricity is accumulated in all the devices from the spray gun to the paint supply system. Therefore, it is extremely dangerous if an operator touches a paint supply system device in which very large discharge energy is accumulated. Accordingly, the paint tank cannot be replenished during operation. In addition, in a multicolor coating color changing device, it is possible to supply paints of other colors other than the paint supply system that is actually in use if the paint supply system of multiple colors is directly connected via a switching valve or the like. Static electricity is accumulated in the system via the switching valve, and the paint tanks of other colors that are not actually used cannot be replenished, increasing the danger range.
[0004]
As a method for reducing such problems of multicolor paint color change, techniques disclosed in Japanese Patent Laid-Open Nos. 4-200663 and 4-200664 have been proposed. First, the technique disclosed in Japanese Patent Laid-Open No. 4-200663 will be described. In this publication, in an electrostatic coating apparatus for conductive paint that coats conductive paint with an electrostatic coating machine to which a high voltage is applied, paint flow is described. A plurality of pumps having an inlet and a paint discharge port through which a predetermined amount of conductive paint introduced from the paint inflow port is discharged at a predetermined flow rate according to the paint discharge amount of the electrostatic coating machine are electrically connected. Installed in an insulated state, each paint supply pipe connected to each color change valve device having a cleaning air supply valve and a cleaning liquid supply valve is detachably connected to the paint inlet of each pump. A paint discharge port of each pump is connected to a switching valve between the discharge port on the electrostatic coating machine side and the outflow channel on the drainage tank side of the paint discharge port, and is connected to the outflow channel on the drainage tank side. Each drainage connected to the drainage tank Tubes electrostatic coating technique made conductive paint as disengageably connected is disclosed.
[0005]
Also, the technology disclosed in Japanese Patent Laid-Open No. 4-200664 will be described. In this publication, an electrostatic coating apparatus for conductive paint that coats a conductive paint with an electrostatic coating machine to which a high voltage is applied is disclosed. A plurality of paint pumping tanks that pump out the required amount of stored conductive paint with air pressure and supply it quantitatively to the electrostatic coating machine, and discharge the required amount of cleaning liquid stored inside with air pressure into the electrostatic coating machine The cleaning liquid pumping tank to be supplied is installed in an electrically insulated state, and is connected to each color changing valve and the cleaning liquid supplying valve arranged in parallel to the manifold connected to the electrostatic coating machine, and each of the paint pumping tank and the cleaning liquid pumping is connected. Each tank is provided with a paint replenishing port and a cleaning liquid replenishing port, and a supply pipe and a cleaning liquid supply for supplying each color of conductive paint from each paint supply source to each paint replenishing port and cleaning liquid replenishing port Tubes electrostatic coating technique made conductive paint as disengageably connected is disclosed.
[0006]
[Problems to be solved by the invention]
The prior art described above, that is, the techniques disclosed in Japanese Patent Application Laid-Open Nos. 4-200663 and 4-200664 have the following problems. First, Japanese Patent Application Laid-Open No. 4-200663 describes that the circuit is relatively complicated and the operation is relatively troublesome. Each paint supply system must have two separation mechanisms: a paint supply system and a paint drainage system . Although not clear in Japanese and Fig., In the system connected to the system in use i.e. electrostatic coating machine color change valve device (9A, 9B, 9C) color change valve (CV ₁ ~CV ₃₎ of Each of the two or more paint supply systems , i.e., the pump and the paint tank, etc., leads to the formation of a conductive path through the conductive paint and exposes it to high potential. The paint cannot be replenished. Therefore, when the paint is replenished, there is a problem that the paint work must be stopped and the high voltage must be cut off and opened before the paint is replenished.
[0007]
In addition, regarding Japanese Patent Application Laid-Open No. 4-200664, even in this technique, during painting, the paint pump tanks (1A, 2B, 2C) and the cleaning liquid pumping tank (3) of multiple colors are connected via conductive paint or cleaning liquid. Since a conductive path is formed and exposed to the danger of high potential, neither paint color paint can be replenished. Therefore, when the paint is replenished, there is a problem that the paint work must be temporarily stopped and the paint must be replenished to the paint pressure feeding tank in a state where the high voltage is cut off and opened.
[0008]
The present invention has been made in view of the above-described problems, and is relatively simple in device configuration and operation in a multicolor electrostatic coating apparatus for conductive paint. The paint color supply system other than the paint color in use is completely disconnected from the high voltage charging circuit so that it is not affected by the high voltage, so that paint replenishment and maintenance can be performed even during painting. Another object of the present invention is to provide a multicolor electrostatic coating color changing device for conductive paints that can be easily changed in color.
[0009]
[Means for Solving the Problems]
In order to solve the above problems, the present invention adopts the following method. That is, in the multicolor electrostatic coating color changing device for conductive paint, a pipe joint a provided so as to be movable on the guide rail, and an electrostatic spray gun connected to the pipe joint a through a pipe line are provided. In addition, a plurality of paint supply circulation circuits are provided in which a liquid tank, a pump, and a pipe joint b that is detachably engaged with the pipe joint a are connected by a pipe, and the pipe joint a and a plurality of systems of paint are provided. The pipe joint b of the supply circulation circuit can be selectively engaged and disengaged , and when the pipe joint a and the pipe joint b of the plurality of paint supply circulation circuits are selectively engaged, the pipe joint The paint supply circulation circuit of the pipe joint b engaged with a is disconnected and insulated, and the paint supply circulation circuit of the pipe joint b disengaged from the pipe joint a is provided on the side of the pipe joint a. conductive, characterized by being configured is grounded with disconnected from the high voltage conductive path It was a multi-color electrostatic coating color sorter of paint.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described. In the present invention, the paint supply circulation circuit of a plurality of systems, that is, the paint supply circulation circuit in which the liquid tank, the pump, and the pipe joint b are connected by a pipe line can be started and stopped independently. In addition, the pipe joint a movably provided on the guide rail and the electrostatic spray gun are connected by a one-way pipe line. Therefore, the paint supply circulation circuit related to the pipe joint b engaged with the pipe joint a is affected by the high voltage applied to the electrostatic spray gun by the conductive paint, but the other paint supply circulation circuit is The conductive path is completely interrupted between the pipe joint a and the pipe joint b, and is not affected by the high voltage. Therefore, the paint supply circulation circuit which is not used even during the painting work can be replenished and maintained without any danger.
[0011]
When the color is changed, one of the grounded liquid tanks (for example, the liquid tank D) is filled with the cleaning liquid, and the circulation circuit of the liquid tank (D) filled with the cleaning liquid during the transition from the A color to the B color. If the pipe joint b and the pipe joint a are engaged, the flow path system from the pipe joint a to the electrostatic spray gun connected by the pipe line is grounded and washed with the cleaning liquid, so there is no color mixing and color. Replacement work can be easily performed.
[0012]
【Example】
Embodiments of the multicolor electrostatic coating color changing device for conductive paint according to the present invention will be specifically described below with reference to the drawings. FIG. 1 is a schematic front view showing a configuration of an embodiment of a multicolor electrostatic coating color changing device for conductive paint according to the present invention, and FIG. 2 is a schematic side view of FIG.
[0013]
In the figure, reference numeral 1 denotes a guide rail fixed to a gantry or a wall surface, 2 denotes a pipe joint a movably provided on the guide rail 1, and the pipe joint a2 is moved on the guide rail 1 by an actuator 3. Possible. In this embodiment, a fluid pressure actuated cylinder mechanism is used as the actuator 3. However, the actuator can be configured by other known methods such as an electric type. 4 is an electrostatic spray gun having a valve mechanism inside. The electrostatic spray gun 4 is connected to a high voltage power source 5 by a cable 6 and a high voltage (80 to 125 KV) is applied to the corona pin of the electrostatic spray gun 4. The The pipe joint a2 and the electrostatic spray gun 4 are connected by a pipe line 7. In connecting the pipe line 7 and the pipe joint a2, since the pipe joint a2 moves, it is necessary to configure so that the movement is not hindered. For this reason, it is easy to interpose a flexible hose or the like. It's a method.
[0014]
In the present embodiment, two electrostatic spray guns 4 are exemplified, but the number of electrostatic spray guns 4 is not limited to two, and is desired depending on conditions such as the shape and size of the object to be coated. It is sufficient to provide as many as. At that time, when a plurality of electrostatic spray guns 4 are provided, in order to be able to adjust the balance of the amount of paint sprayed from each electrostatic spray gun 4, a flow rate adjusting valve 8 is provided for each. Is desirable. 9 is a dump valve, 10 is a waste liquid receiver, and the dump valve 9 and the waste liquid receiver 10 are used when the inside of the pipe line 7 is cleaned. Although not shown, when waste liquid is recovered in an external recovery container (such as a drum can), a dump shuttle may be provided to completely electrically insulate the external recovery container and the system system.
[0015]
Reference numeral 11 denotes a liquid tank for paint (one of which is used for cleaning liquid), and 12 denotes a pump disposed on the liquid tank 11. Reference numeral 13 denotes a pipe joint b. The pipe joint b13 has a male-female relation with the pipe joint a2 and has a structure that can be freely engaged and disengaged. The pipe joint a2 and the pipe joint b13 are provided with a check valve mechanism having a structure in which the liquid passage communicates with each other only when engaged, and automatically closes and does not leak when detached. ing. The pipe joint b13 is connected to an end of the lot of the actuator 14 for performing an engagement / disengagement operation with an electrical insulating material 15 interposed. In this embodiment, a fluid pressure actuated cylinder mechanism is used as the actuator 14. In addition, the pipe joint b13 is configured to be automatically grounded by the ground wire 23 at a descending point where it is separated from the pipe joint a2. Reference numeral 16 denotes a pressure adjusting valve, and 24 denotes a circulation valve.
[0016]
These devices, that is, the liquid tank 11, the pump 12, the pipe joint b13, the pressure regulating valve 16, and the circulation valve 24 are connected by a pipe line 17 and a pipe line 18 to form a paint supply circulation circuit. That is, the conductive liquid paint stored in the liquid tank 11 is pumped up by the pump 12, reaches the pipe joint b <b> 13 from the pipe line 17, passes through the pipe line 18, the pressure regulating valve 16, and the circulation valve 24 and is pumped again. To the suction side or a part thereof returns to the liquid tank 11. At that time, the pressure in the paint supply circulation circuit is maintained at a predetermined pressure by the pressure regulating valve 16.
[0017]
Since the pipe joint b13 moves up and down, the pipe line 17 and the pipe line 18 connected to the pipe joint b13 need to be configured so as not to hinder the movement, and therefore a flexible hose or the like is interposed. Is a simple method. Reference numeral 19 denotes an insulating material for electrically insulating the liquid tank 11. In the paint supply circulation circuit, high potential static electricity may remain charged even when the pipe joint a2 and the pipe joint b13 are disconnected, and the liquid tank 11 remains charged in the paint supply circulation circuit during maintenance. A relay 20 for grounding and releasing static electricity and a ground circuit 21 are connected to each other, and a double safety mechanism is formed in cooperation with the ground wire 23 described above. Reference numeral 22 denotes an object to be grounded.
[0018]
In this embodiment, for convenience, there are provided three paint supply circulation circuits in which the liquid tank 11, the pump 12, the pipe joint b13, the pressure regulating valve 16 and the circulation valve 24 are connected by the pipe line 17 and the pipe line 18. Although illustrated in the figure, the present invention is not limited to this, and an arbitrary number of systems may be provided according to the number of required paint colors.
[0019]
Next, the operation of the electrostatic coating color changing device configured as described above will be described. First, the liquid tank 11 is filled with conductive paints A, B, and C of different colors. For the sake of convenience, it is assumed that D is filled with a cleaning liquid in order to clean the flow path of the paint when changing colors. Hereinafter, the case where the paint A shown in FIG. 1 is applied will be described as a representative example for convenience, but the same operation is performed when another color is selected. The actuator 3 is operated to set the pipe joint a2 to a position where it engages with the pipe joint b13 of the paint supply circulation circuit of the target color (color A in FIG. 1), and the actuator 14 is further operated to operate the pipe joint a2 and the pipe. The joint b13 is engaged. Then, the high voltage power source 5 is activated and a high voltage is applied to the corona pin of the electrostatic spray gun 4. At this time, the dump valve 9 is closed.
[0020]
Next, when the paint color A pump 12 is activated, the conductive liquid paint A stored in the liquid tank 11 is pumped up by the pump 12, reaches the pipe joint b <b> 13 from the pipe line 17, the pipe line 18, and the pressure adjustment valve 16. The paint A that circulates in the paint supply circulation circuit that returns to the suction side of the pump 12 or the liquid tank 11 again through the circulation valve 24 and that is maintained at a predetermined pressure passes from the pipe joint b13 to the pipe joint a2. , Through the conduit 7 and the flow rate adjusting valve 8 to the electrostatic spray gun 4. When the valve mechanism incorporated in the electrostatic spray gun 4 is opened, the coating color A is ejected from the nozzle of the electrostatic spray gun 4 and applied to the surface of the grounded article 22.
[0021]
At this time, the high voltage applied to the electrostatic spray gun 4 reaches all devices of the paint supply circulation circuit of the paint A system in which the conductive path is formed via the conductive paint A. Therefore, all devices where conductive paths are formed must be kept in an insulated state. Although not shown in the figure, it is also necessary to isolate it with a protective fence or the like so that the operator does not touch these devices. In Figure 1 all the equipment in order to keep an insulated state, the ground circuit 21 maintains the relay 20 in an open state, disconnecting from the ground line 2 3 by the actuator 14 rises, the insulating material provided on the liquid tank 11 19, the entire system is maintained in an insulated state. And in painted coating color A is paint color B other than paint color A, with completely disconnected from the high voltage conductive path in the supply circulation circuit pipe joint b13 portion of paint color C and wash D, ground line 2 3 and Since it is grounded by the closed relay 20 and the ground circuit 21, it is not affected by the high voltage.
[0022]
Next, the procedure of color change work will be described. First, in order to avoid color mixing of the front color and the rear color, it is necessary to clean the pipe joint a, the pipe line 7, the flow rate adjusting valve 8, and the electrostatic spray gun 4. Since a high voltage is not particularly required for the cleaning operation, the high voltage power supply is shut off before the cleaning operation is started. Next, the actuator 14 is operated to separate the pipe joint a2 and the pipe joint b13. The pipe joint a2 and the pipe joint b13 separated at this time are provided with a check valve mechanism for preventing liquid leakage, so that no liquid leakage occurs.
[0023]
Next, the actuator 3 is operated to move the pipe joint a2 to a position where the pipe joint a2 is engaged with the pipe joint b13 connected to the D cleaning liquid supply circulation circuit filled with the cleaning liquid. Then, the actuator 14 of the cleaning liquid supply circulation circuit D is operated to engage the pipe joint b13 and the pipe joint a2. When the dump valve 9 is opened and the pump 12 for the cleaning liquid D is activated, the paint A remaining in the pipe 7 is pushed out into the waste liquid receiver 10 by the cleaning liquid D and the inside of the pipe 7 is cleaned. When the inside of the pipe line 7 is cleaned, the dump valve 9 is closed and the valve mechanism incorporated in the electrostatic spray gun 4 is opened, whereby the flow rate adjusting valve 8 and the electrostatic spray gun 4 are cleaned. When the flow rate adjusting valve 8 and the electrostatic spray gun 4 are cleaned, the valve mechanism built in the electrostatic spray gun 4 is closed and the cleaning operation is finished.
[0024]
Next, the pipe joint a2 and the pipe joint b13 that have been engaged with the supply circulation circuit of the cleaning liquid D are disconnected, the pipe joint a2 is moved, and the pipe joint b13 of the paint supply circulation circuit of the paint color B is engaged. By activating the pump 12 for the paint B, the paint B is supplied to the electrostatic spray gun 4 to complete the color change from the paint color A to the paint color B. When a high voltage is applied to the electrostatic ejection gun 4 to open the valve mechanism inside the electrostatic ejection gun 4, the coating color B is applied to the article 22 to be coated.
[0025]
By configuring the coating material supply system in the circulation circuit including the pipe joint b13 as described above, the pipe joint portion for engaging and disengaging the pipe line can be completed at one place, which is much simpler than the prior art. Other than the paint supply circulation circuit in use, that is, other than the paint supply circulation circuit in which the pipe joint a2 and the pipe joint b13 are engaged, the high voltage power supply and the pipe joint b13 are completely disconnected and grounded. since it is, or supplemented with Ku coating such that even during operation is influenced by the high voltage, Ru can perform maintenance work for maintenance or the like. However, since there is a possibility that static electricity at the time before disconnection of the pipe joint b13 may remain, the relay 20 may be closed and the remaining static electricity may be released through the ground circuit 21 before maintenance work is started. is necessary.
[0026]
【The invention's effect】
As described above, according to the multi-color electrostatic coating color changing device for conductive paint of the present invention, the device configuration and operation are relatively simple and simple compared to the prior art, and painting with a plurality of coating colors is possible. In the work, the paint color supply system other than the paint color in use is configured to be completely disconnected from the high voltage charge circuit so that it is not affected by the high voltage. It is possible to provide a multicolor electrostatic coating color changing device for conductive paints that can be used inside and that can be easily changed.
[Brief description of the drawings]
FIG. 1 is a schematic front view showing a configuration of an embodiment of the present invention.
FIG. 2 is a schematic side view of FIG. 1;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Guide rail, 2 ... Pipe joint a, 3 ... Actuator, 4 ... Electrostatic ejection gun, 11 ... Liquid tank, 12 ... Pump, 13 ... Pipe joint b, 14 ... Actuator, 16 ... Pressure regulating valve, 22 ... Covered Paint.

Claims

In the multi-color electrostatic coating color changing device for conductive paint, a pipe joint a provided so as to be movable on the guide rail, an electrostatic spray gun connected to the pipe joint a through a pipe line, and further, A plurality of paint supply circulation circuits in which a liquid tank, a pump, and a pipe joint b detachably engaged with the pipe joint a are connected by a pipe line are provided, and the pipe joint a and a plurality of systems of paint supply circulation are provided. The pipe joint b of the circuit can be selectively engaged and disengaged, and when the pipe joint a and the pipe joint b of the plurality of paint supply circulation circuits are selectively engaged, the pipe joint a The paint supply circulation circuit of the pipe joint b engaged is disconnected and insulated, and the paint supply circulation circuit of the pipe joint b disengaged from the pipe joint a is a high voltage on the pipe joint a side. characterized by being configured is grounded with disconnected from conductive path, the conductive paint Irosei electrostatic coating color sorter.