JP2004243218A

JP2004243218A - Coating device

Info

Publication number: JP2004243218A
Application number: JP2003035615A
Authority: JP
Inventors: Hiroshi Samejima; 弘鮫島
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-02-13
Filing date: 2003-02-13
Publication date: 2004-09-02

Abstract

<P>PROBLEM TO BE SOLVED: To simply and efficiently carry out coating by smoothly heating an object to be coated such as a piston. <P>SOLUTION: In the coating device, a plurality of objects 3 to be coated are subsequently and intermittently conveyed to a coating position A by a conveying means 2 and the objects 3 to be coated positioned at a coating position A are subsequently coated by a coating means 2. A heating position B where the objects 3 to be coated are subsequently and intermittently conveyed is provided at an upstream side of the coating position A. A heating means 18 for heating the objects 3 to be coated positioned at the heating position B by low frequency induction heating is provided. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、例えばエンジンのピストン等の複数の被塗装物を順次塗装する塗装装置に関する。
【０００２】
【従来の技術】
多数の被塗装物を塗装する塗装装置には、搬送コンベア等を備える搬送手段により、複数の被塗装物を塗装位置に順次間欠的に搬送して、塗装位置にある被塗装物を塗装ガンを有する塗装手段で順次塗装するようにしたものがある（例えば、特許文献１）。
しかし、エンジンのピストン等を特殊コーティング塗料により塗装する場合、塗装する前に、被塗装物であるピストンを１１０°Ｃ〜１２０°Ｃに加熱する必要があり、従来では、加熱炉でピストンを加熱した後、そのピストンを加熱炉から手作業により取り出して、搬送手段の搬送コンベア等の保持台に保持させて、搬送コンベア等の間欠的な移動によって、ピストンを塗装位置に搬送して、塗装位置でピストンを塗装手段で順次塗装するようにしていた。
【０００３】
【特許文献１】
特開平２−４８０６１号公報
【０００４】
【発明が解決しようとする課題】
従って、従来の場合、加熱炉でピストン等の被塗装物を加熱した後、そのピストンを加熱炉から手作業により取り出して、搬送手段の搬送コンベア等の保持台に保持させなければならず、加熱炉で加熱したピストンを取り出して保持台に置く作業が非常に面倒であり、また塗装効率も非常に悪かった。
本発明は上記問題点に鑑み、ピストン等の被塗装物をスムーズに加熱して、簡単かつ効率よく塗装できるようにしたものである。
【０００５】
【課題を解決するための手段】
この技術的課題を解決する本発明の技術的手段は、搬送手段２により、複数の被塗装物３を塗装位置Ａに順次間欠的に搬送して、塗装位置Ａにある被塗装物３を塗装手段２で順次塗装するようにした塗装装置において、
塗装位置Ａの上手側に、被塗装物３が順次間欠的に搬送される加熱位置Ｂが設けられ、加熱位置Ｂにある被塗装物３を低周波誘導加熱により加熱する加熱手段１８が設けられている点にある。
【０００６】
本発明の他の技術的手段は、前記加熱手段１８は、環状に形成された誘導コイル２０を有し、誘導コイル２０に低周波電流を流すことにより、誘導コイル２０内に配置された被塗装物３を低周波誘導加熱により加熱するように構成されている点にある。
本発明の他の技術的手段は、前記加熱手段１８は、誘導コイル２０が加熱位置Ｂにある被塗装物３の周囲を取り囲む加熱動作位置Ｄと、被塗装物３の間欠移動を妨げないように加熱動作位置Ｄから退避する退避位置Ｅとに移動自在とされている点にある。
【０００７】
本発明の他の技術的手段は、搬送手段２により被塗装物３を間欠移動するとき、加熱手段１８を退避位置Ｅに退避させると共に、搬送手段２による間欠移動が停止したとき、加熱手段１８を加熱動作位置Ｄに移動させるように、加熱手段１８を、搬送手段２に連動して、加熱動作位置Ｄと退避位置Ｅとに往復移動させるようにした点にある。
本発明の他の技術的手段は、加熱位置Ｂと塗装位置Ａとの間に、加熱後の被塗装物３が順次間欠的に搬送されて被塗装物３を均熱化する均熱位置が設けられている点にある。
【０００８】
本発明の他の技術的手段は、前記加熱位置Ｂは、搬送方向に複数設けられ、前記加熱手段１８は、複数の加熱位置Ｂに対応して複数の誘導コイル２０を有し、各加熱位置Ｂにある被塗装物３を複数の誘導コイル２０でそれぞれ取り囲む加熱動作位置Ｄと、各誘導コイル２０が各加熱位置Ｂにある被塗装物３から外れるように加熱動作位置Ｄから退避する退避位置Ｅとに移動自在とされている点にある。
本発明の他の技術的手段は、搬送手段２は、回転テーブル４を備え、回転テーブル４に、周方向に所定間隔をおいて被塗装物３を保持する複数の保持台１１が設けられ、回転テーブル４は、周方向に所定間隔おきに間欠的に回転して保持台１１の被塗装物３を加熱位置Ｂ及び塗装位置Ａに順次間欠的に搬送するように構成されている点にある。
【０００９】
本発明の他の技術的手段は、塗装手段４７は、塗装位置Ａにある被塗装物３に向けて塗料を噴射する塗装ガン５１を備え、塗装ガン５１は、被塗装物３を広範囲に亘って塗装するように往復移動自在とされている点にある。
本発明の他の技術的手段は、塗装位置Ａにある被塗装物３を回転させる回転駆動手段５５が設けられている点にある。
【００１０】
【発明の実施の形態】
以下、本発明の実施の形態を図面に基づき説明する。
図１〜図３において、１は支持台で、図示省略のキャスターを介して床等に移動可能に設置されている。
２は複数の被塗装物３を順次間欠的に搬送する搬送手段で、回転テーブル４と支持筒体５とを備える。支持筒体５の上端部に回転テーブル４の中央部が外嵌固定されている。支持台１に支持軸７が上方突設され、支持軸７はボルト等の締結具８により支持台１に固設されている。
【００１１】
支持筒体５は支持軸７に外嵌されてベアリング９により回転自在に支持されている。これにより、回転テーブル４は水平状態に保持されると共に、支持筒体５と共に支持軸７廻りに回転自在に支持されている。支持筒体５はウオームギヤ１０等を介して図示省略の回転テーブル駆動用の電動モータにより間欠的に回転駆動されるようになっている。
回転テーブル４の外周部に、周方向に所定間隔をおいて被塗装物３を保持する複数の保持台１１が設けられている。具体的には、保持台１１は１２個あって、回転テーブル４の外周部に周方向全周に亘って等間隔をおいて設けられている。従って、周方向に隣り合う保持台１１同士は、回転テーブル４の中心から３０°ずつ変位した位置に配置されている。各保持台１１上に受け具１２を介してエンジンのピストン等の被塗装物３が載置され、これにより被塗装物３が保持台１１に保持されるようになっている。
【００１２】
各保持台１１は、縦方向の支軸１３を介して回転テーブル４に支持され、支軸１３は、回転テーブル４の外周部に上下貫通状に配置されて、ベアリング１４により軸心廻りに回転自在に保持され、支軸１３の上端部に保持台１１が固設され、支軸１３の下端部に回転ローラ１５が固設されている。従って、各保持台１１は、回転ローラ１５と共に回転テーブル４の外周部にベアリング１４を介して支軸１３廻りに回転自在に支持されている。
回転テーブル４の前側に、被塗装物３を順次間欠的に搬送する塗装位置Ａが設けられ、回転テーブル４の塗装位置Ａよりも上手側に、加熱位置Ｂが設けられている。この加熱位置Ｂは搬送方向に複数あって、被塗装物３を順次間欠的に搬送する第１加熱位置Ｂ１と第２加熱位置Ｂ２と第３加熱位置Ｂ３とが周方向に所定間隔ｂをおいて設けられている。塗装位置Ａと加熱位置Ｂとの間に、加熱後の被塗装物３が順次間欠的に搬送されて被塗装物３を均熱化する均熱位置Ｃが設けられている。
【００１３】
前記回転テーブル駆動用の電動モータは、回転テーブル４が図２に示す矢印ａ方向に間欠的に回転駆動され、回転テーブル４が周方向に所定間隔ｂだけ回転する毎に、数秒間（例えば６秒間）回転を停止するように、後述する図示省略の制御手段により制御される。
１８は被塗装物３を加熱する加熱手段で、図３及び図４にも示すように、ケース体１９と３個の誘導コイル２０（２０ａ，２０ｂ，２０ｃ）とを備える。ケース体１９は、上壁２２と底壁２３と外周壁２４とを有する長方形の箱形に形成され、外周壁２４は前後側壁と左右側壁とを具備する角筒状に形成されている。ケース体１９に、上下方向に貫通する３個の貫通孔２６（２６ａ，２６ｂ，２６ｃ）が設けられると共に、貫通孔２６を取り囲むように３個の筒体２７（２７ａ，２７ｂ，２７ｃ）が設けられている。貫通孔２６の上端側は蓋体２８により開閉自在に閉塞されている。
【００１４】
３個の誘導コイル２０は環状に形成されて、貫通孔２６乃至筒体２７の外周を取り囲むようにケース体１９内に組み込まれ、誘導コイル２０は、貫通孔２６乃至筒体２７と共に、前記第１加熱位置Ｂ１、第２加熱位置Ｂ２、第３加熱位置Ｂ３に対応するように円弧状に配置されている。
３１は加熱手段１８を昇降する昇降手段で、コの字状の支持フレーム３２と、一対の昇降用ガイド３３と、エアシリンダにより構成したアクチュエータ３４とを備える。支持フレーム３２は支持台１１の右側端部に上方突設されている。
【００１５】
前記一対の各昇降用ガイド３３は、レール体３６と上下一対の移動体３７とを有し、レール体３６は、支持フレーム３２の幅方向両側に支持部材３８を介して上下方向に固設されている。上下一対の移動体３７は、ケース体１９に突設した取付部材３９に固着され、移動体３７はレール体３６に上下方向に移動自在に嵌合保持されている。従って、加熱手段１８乃至ケース体１９は、一対の昇降用ガイド３３によって上下方向に移動自在に支持されている。
アクチュエータ３４は、エアの給排によってシリンダ本体４１からシリンダロッド４２が上下方向に出退移動するように構成され、シリンダ本体４１は支持フレーム３２側に固定され、シリンダロッド４２の上端が取付体４３を介してケース体１９に固定されており、アクチュエータ３４の伸縮動作によって、加熱手段１８乃至ケース体１９を上下方向に往復移動し、これにより、加熱手段１８は、各加熱位置Ｂにある被塗装物３を複数の誘導コイル２０でそれぞれ取り囲む加熱動作位置Ｄと、各誘導コイル２０が各加熱位置Ｂにある被塗装物３から外れるように加熱動作位置Ｄから上方に退避する退避位置Ｅとに移動自在とされている。そして、加熱手段１８が退避位置Ｅから加熱動作位置Ｄに下降したとき、図４に示すように加熱手段１８の各筒体２７（貫通孔２６）に対して各加熱位置Ｂにある被塗装物３が下側から内嵌されて、各加熱位置Ｂにある被塗装物３を複数の誘導コイル２０でそれぞれ取り囲むようになっている。
【００１６】
４７は塗装手段で、固定台４８と支持体４９と塗装具本体５０とを備え、支持体４９は固定台４８上に上方突設され、塗装具本体５０は、塗装ガン５１を有すると共に、支持体４９にレール部材５２を介して上下移動自在に支持され、塗装具本体５０は、塗装ガン５１から塗料、例えばピストン用の特殊コーティング塗料を前方に向けて噴射して、塗装位置Ａにある被塗装物３を塗装するようになっている。また、塗装具本体５０は、図示省略の塗装具移動用の電動モータにより上下方向に往復移動されるようになっており、これにより、塗装ガン５１で、被塗装物３を上下方向に広範囲に亘って塗装するようになっている。
【００１７】
５５は塗装位置Ａにある被塗装物３を回転させる回転駆動手段で、駆動プーリ５６と従動プーリ５７とＶベルト５８とを備え、Ｖベルト５８は、駆動プーリ５６と従動プーリ５７との間に巻回され、塗装位置Ａにある保持台１１の回転ローラ１５に圧接しており、図示省略の被塗装物回転用の電動モータによって駆動プーリ５６が回転駆動されることにより、Ｖベルト５８が回動して塗装位置Ａにある保持台１１が縦方向の支軸１３廻りに回転駆動されるようになっている。これにより、塗装位置Ａにある被塗装物３が支軸１３廻りに回転（自転）され、塗装手段４７の塗装ガン５１によって、被塗装物３が全周に亘ってまんべんなく塗装されるようになっている。
【００１８】
図５に示すように、インバータ６１の入力端子Ｒ，Ｓ，Ｔに商用の三相交流電源が接続され、インバータ６１の出力端子Ｕ，Ｖに、コンデンサを有する増幅器６３を介して、複数の誘導コイル２０（図例では３個）が並列に接続されている。インバータ６１は周波数設定器を有する汎用型のインバータであって、三相交流電源の三相電流を直流に変換して、周波数設定器により設定した任意の周波数の単相交流電流を出力するように構成されており、例えばインバータ６１から５０Ｈｚ〜６０Ｈｚの低周波電流を出力するように設定されている。従って、１の電源から、インバータ６１及び増幅器６３を介して、誘導コイル２０に低周波電力を供給して加熱位置Ｂにある複数の被塗装物３を低周波誘導加熱により同時に加熱するようになっている。
【００１９】
前記回転テーブル駆動用の電動モータ、アクチュエータ３４、加熱手段１８、被塗装物回転用の電動モータ、塗装具移動用の電動モータ及び塗装具本体５０等は、図示省略の制御手段により互いに連動して動作するように制御されるようになっており、回転テーブル駆動用の電動モータは、上記の如く回転テーブル４が周方向に所定間隔ｂだけ回転する毎に、数秒間（例えば６秒間）回転を停止するように制御され、これに対応して、アクチュエータ３４は、回転テーブル４が周方向に間欠移動するとき、加熱手段１８を退避位置Ｅに退避させると共に、回転テーブル４が間欠移動を停止したとき、加熱手段１８を加熱動作位置Ｄに移動させるように、加熱手段１８を、搬送手段２（回転テーブル４）に連動して、加熱動作位置Ｄと退避位置Ｅとに往復移動させるように制御される。
【００２０】
また、加熱手段１８は、該加熱手段１８が加熱動作位置Ｄに移動したとき、各誘導コイル２０に低周波誘導電流を流すようになっている。誘導コイル２０に低周波誘導電流を流すことにより、誘導コイル２０から加熱位置Ｂにある被塗装物３を通るように磁力線が発生して、加熱位置Ｂにある被塗装物３を低周波誘導加熱により加熱するようになっている。
被塗装物回転用の電動モータは、回転テーブル４が周方向に間欠移動するとき、駆動を停止し、回転テーブル４が間欠移動を停止したとき、駆動して被塗装物３が保持体１１と共に回転するように、搬送手段２（回転テーブル４）に連動して制御される。
【００２１】
塗装具移動用の電動モータは、回転テーブル４が周方向に間欠移動するとき、駆動を停止すると共に、回転テーブル４が間欠移動を停止したとき、塗装具本体５０が上下方向に往復移動するように、搬送手段２（回転テーブル４）に連動して制御される。
また、塗装具本体５０は、回転テーブル４が周方向に間欠移動するとき、作動を停止して塗装ガン５１からの塗料の噴射を停止すると共に、回転テーブル４が間欠移動を停止したとき、作動して塗装ガン５１から塗料を前方に向けて噴射するように制御される。
【００２２】
上記実施の形態によれば、エンジンのピストン等の被塗装物３を塗装する場合、電源スイッチを投入すると、回転テーブル４が矢印ａ方向に間欠的に移動して、回転テーブル４が周方向に所定間隔ｂだけ回転する毎に、数秒間（例えば６秒間）回転を停止するので、回転テーブル４の加熱位置Ｂよりも上手側で、保持台１１上に被塗装物３を受け具１２を介して載せてゆけばよく、保持台１１に保持した被塗装物３は、回転テーブル４の間欠回動によって、第１加熱位置Ｂ１、第２加熱位置Ｂ２、第３加熱位置Ｂ３、均熱位置Ｃ、塗装位置Ａに順次搬送される。なお、被塗装物３に塗装をしない部分があるときには、被塗装物３の塗装しない部分にマスクを装着するようにすればよい。
【００２３】
まず、被塗装物３が第１加熱位置Ｂ１に搬送されると、加熱手段１８が退避位置Ｅから加熱動作位置Ｄに下降することにより、被塗装物３を加熱手段１８の誘導コイル２０ａが取り囲み、誘導コイル２０ａに低周波誘導電流が流れることにより、誘導コイル２０ａから被塗装物３を通るように磁力線が発生して、被塗装物３を低周波誘導加熱により加熱する。次に、被塗装物３が第２加熱位置Ｂ２に搬送されると、同様に加熱手段１８が退避位置Ｅから加熱動作位置Ｄに下降することにより、誘導コイル２０ｂから被塗装物３を通るように磁力線を発生させて、被塗装物３を低周波誘導加熱により加熱する。また、第３加熱位置Ｂ３で、同様に被塗装物３を低周波誘導加熱により加熱する。
【００２４】
従って、被塗装物３は、塗装位置Ａよりも上手側の第１加熱位置Ｂ１、第２加熱位置Ｂ２、第３加熱位置Ｂ３で一定期間（例えば６秒間）ずつ低周波誘導加熱することにより１１０°Ｃ〜１２０°Ｃ以上に十分に加熱される。
この場合、低周波電流が、並列に接続された複数の誘導コイル２０に流れることにより、複数の誘導コイル２０から加熱位置Ｂにある各被塗装物３を通るように磁力線が発生して、複数の被塗装物３を低周波誘導加熱により迅速に加熱することができる。また、電源からインバータ３１を介して５０Ｈｚ〜６０Ｈｚの低周波電力に変換し、さらにコンデンサを有する増幅器６３によって、インバータ６１の出力（周波数電圧）をアップさせることができる。このため、インバータ６１の出力端子Ｒ，Ｓ，Ｔ側に接続された商用電源を、インバータ６１と増幅器６３との組み合わせで、出力を約１５０％アップさせて、大きな省エネの効果を得ることができる。しかも、複数（例えば３個）の誘導コイル２０に低周波電流が供給されるため、汎用型の比較的容量の大きいインバータ６１を使用し、また比較的大容量のコンデンサを有する増幅器６３を使用するにも拘わらず、力率が非常によくなり、電力効率を高めて、この点からも大幅な省エネを達成することができる。
【００２５】
そして、被塗装物３が均熱位置Ｃに搬送されると、回転テーブル４が停止する一定期間（例えば６秒間）の間に、第１加熱位置Ｂ１、第２加熱位置Ｂ２及び第３加熱位置Ｂ３で加熱した後の被塗装物３が、全体に亘って同一温度になるように均熱化される。
次に、被塗装物３が塗装位置Ａに搬送されると、塗装具本体５０の塗装ガン５１から塗料を前方に向けて噴射して、１１０°Ｃ〜１２０°Ｃに加熱された状態の被塗装物３が塗装される。このとき、塗装ガン５１は上下方向に往復移動され、また、塗装位置Ａにある被塗装物３が支軸１３廻りに回転（自転）されるので、塗装手段４７の塗装ガン５１によって、被塗装物３が全周に亘ってまんべんなく塗装される。
【００２６】
従って、例えば、図２に示すように、作業者Ｍが加熱位置Ｂの上手側に位置して、塗装位置Ａで塗装された被塗装物３を保持台１１から取り外すと共に、加熱するする前の新たな被塗装物３を、作業者Ｍ側に搬送されてくる保持台１１に順次保持してゆけばよく、複数の被塗装物３は加熱された後に順次効率よく塗装される。このため、エンジンのピストン等を特殊コーティング塗料により塗装する場合、従来のように加熱炉でピストン等の被塗装物を加熱した後に、そのピストンを加熱炉から手作業により取り出して、搬送手段の搬送コンベア等の保持台１１に保持させような面倒な作業をする必要がなくなり、ピストン等の被塗装物３をスムーズに加熱して、簡単かつ効率よく塗装できるようになる。
【００２７】
なお、前記実施の形態では、加熱位置Ｂは、搬送方向に３個設けられ、前記加熱手段１８は、複数の加熱位置Ｂに対応して３個の誘導コイル２０を有しているが、これに代え、加熱位置Ｂを、搬送手段の搬送方向に１個又は２個或いは４個以上設けると共に、これに対応して、誘導コイル２０を１個又は２個或いは４個以上設けるようにしてもよい。
また、前記実施の形態では、搬送手段２は回転テーブル４を備え、回転テーブル４を間欠的に回転駆動するようにしているが、回転テーブル４にに代えてに搬送コンベアを使用し、搬送コンベアを間欠的に駆動して、複数の被塗装物３を加熱位置Ｂと塗装位置Ａとに順次搬送するようにしてもよい。
【００２８】
【発明の効果】
本発明によれば、ピストン等の被塗装物をスムーズに加熱して、簡単かつ効率よく塗装することができる。
【図面の簡単な説明】
【図１】本発明の一実施形態を示す塗装装置の正面断面図である。
【図２】同平面図である。
【図３】同加熱手段の斜視図である。
【図４】同加熱手段の側断面図である。
【図５】同加熱手段の電気回路図である。
【符号の説明】
２搬送手段
３被塗装物
４回転テーブル
１１保持台
１８加熱手段
２０誘導オイル
４７塗装手段
５１塗装ガン
５５回転駆動手段[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a coating apparatus for sequentially coating a plurality of objects to be coated such as an engine piston.
[0002]
[Prior art]
In a coating apparatus for coating a large number of workpieces, a plurality of workpieces are sequentially and intermittently transported to a coating position by a transport unit having a transport conveyor or the like. There is a method in which the coating is sequentially performed by a coating means having the same (for example, Patent Document 1).
However, when a piston or the like of an engine is coated with a special coating paint, it is necessary to heat the piston to be coated to 110 ° C to 120 ° C before coating. Conventionally, the piston is heated by a heating furnace. After that, the piston is taken out of the heating furnace by hand, and is held on a holding table such as a conveyor of a transfer means. Then, the pistons were sequentially painted by the painting means.
[0003]
[Patent Document 1]
JP-A-2-48061
[Problems to be solved by the invention]
Therefore, in the conventional case, after the object to be coated such as a piston is heated in a heating furnace, the piston must be manually removed from the heating furnace and held on a holding table such as a conveyor of the transfer means. The work of taking out the piston heated in the furnace and placing it on the holding table was very troublesome, and the coating efficiency was very poor.
SUMMARY OF THE INVENTION In view of the above problems, the present invention is to easily and efficiently coat an object to be coated such as a piston by heating it smoothly.
[0005]
[Means for Solving the Problems]
The technical means of the present invention for solving this technical problem is that a plurality of objects to be coated 3 are sequentially and intermittently conveyed to a coating position A by a conveying means 2 to coat the object 3 at the coating position A. In the coating apparatus which is configured to perform the coating sequentially by the means 2,
On the upstream side of the coating position A, there is provided a heating position B where the workpiece 3 is sequentially and intermittently conveyed, and a heating means 18 for heating the workpiece 3 at the heating position B by low-frequency induction heating is provided. It is in the point.
[0006]
Another technical means of the present invention is that the heating means 18 has an induction coil 20 formed in an annular shape, and a low-frequency current is caused to flow through the induction coil 20 so that the object to be coated placed in the induction coil 20 is formed. The object 3 is configured to be heated by low-frequency induction heating.
Another technical means of the present invention is that the heating means 18 does not hinder the heating operation position D where the induction coil 20 surrounds the workpiece 3 at the heating position B and the intermittent movement of the workpiece 3. And a retreat position E that retreats from the heating operation position D.
[0007]
Another technical means of the present invention is to retreat the heating means 18 to the retreat position E when the workpiece 3 is intermittently moved by the transport means 2 and to stop the heating means 18 when the intermittent movement by the transport means 2 is stopped. Is moved to the heating operation position D, and the heating means 18 is reciprocated between the heating operation position D and the retreat position E in conjunction with the transport means 2.
Another technical means of the present invention is that, between the heating position B and the coating position A, the object to be coated 3 after the heating is intermittently conveyed intermittently to equalize the temperature of the object to be coated 3. It is in the point provided.
[0008]
According to another technical means of the present invention, a plurality of the heating positions B are provided in the transport direction, and the heating means 18 has a plurality of induction coils 20 corresponding to the plurality of the heating positions B. B, a heating operation position D surrounding the object 3 to be coated with the plurality of induction coils 20, and a retreat position at which the induction coils 20 retreat from the heating operation position D so as to deviate from the object 3 at each heating position B. The point is that it can be moved to E.
Another technical means of the present invention is that the transport means 2 includes a rotary table 4, and the rotary table 4 is provided with a plurality of holding tables 11 for holding the workpieces 3 at predetermined intervals in a circumferential direction, The rotary table 4 is configured to rotate intermittently at predetermined intervals in the circumferential direction and to convey the workpiece 3 of the holding table 11 to the heating position B and the coating position A sequentially and intermittently. .
[0009]
Another technical means of the present invention is that the coating means 47 includes a coating gun 51 for spraying paint toward the workpiece 3 at the coating position A, and the coating gun 51 covers the workpiece 3 over a wide range. The point is that it can be moved back and forth like painting.
Another technical means of the present invention resides in that a rotation driving means 55 for rotating the workpiece 3 at the coating position A is provided.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 3, reference numeral 1 denotes a support base, which is movably installed on a floor or the like via casters (not shown).
Reference numeral 2 denotes a transport unit for sequentially and intermittently transporting a plurality of objects 3 to be coated, and includes a rotary table 4 and a support cylinder 5. The center of the turntable 4 is externally fitted and fixed to the upper end of the support cylinder 5. A support shaft 7 protrudes upward from the support table 1, and the support shaft 7 is fixed to the support table 1 by fasteners 8 such as bolts.
[0011]
The support cylinder 5 is fitted around the support shaft 7 and is rotatably supported by bearings 9. Thus, the rotary table 4 is held in a horizontal state, and is supported rotatably around the support shaft 7 together with the support cylinder 5. The supporting cylinder 5 is intermittently driven to rotate by a rotary table driving electric motor (not shown) via a worm gear 10 and the like.
A plurality of holding tables 11 that hold the workpiece 3 at predetermined intervals in the circumferential direction are provided on the outer peripheral portion of the turntable 4. Specifically, there are twelve holding tables 11, which are provided on the outer peripheral portion of the turntable 4 at equal intervals over the entire circumference in the circumferential direction. Therefore, the holding tables 11 adjacent in the circumferential direction are arranged at positions displaced by 30 ° from the center of the turntable 4. A workpiece 3 such as an engine piston is placed on each holding base 11 via a receiving member 12, whereby the workpiece 3 is held on the holding base 11.
[0012]
Each holding table 11 is supported on a rotary table 4 via a vertical support shaft 13, and the support shaft 13 is disposed in a vertically penetrating manner on the outer peripheral portion of the rotary table 4, and is rotated around a shaft center by a bearing 14. It is freely held, and the holding base 11 is fixedly provided at the upper end of the support shaft 13, and the rotating roller 15 is fixedly provided at the lower end of the support shaft 13. Accordingly, each holding table 11 is rotatably supported on the outer periphery of the rotary table 4 together with the rotary roller 15 via the bearing 14 around the support shaft 13.
A coating position A for intermittently transporting the object 3 to be coated is provided on the front side of the turntable 4, and a heating position B is provided on the turntable 4 above the coating position A. There are a plurality of heating positions B in the transport direction, and a first heating position B1, a second heating position B2, and a third heating position B3 for sequentially and intermittently transporting the workpiece 3 are spaced at a predetermined interval b in the circumferential direction. It is provided. Between the coating position A and the heating position B, there is provided a soaking position C where the object 3 after heating is transported intermittently one after another to equalize the temperature of the object 3 to be coated.
[0013]
In the electric motor for driving the rotary table, the rotary table 4 is intermittently driven to rotate in a direction indicated by an arrow a shown in FIG. The rotation is stopped by control means (not shown), which will be described later, to stop the rotation.
Reference numeral 18 denotes a heating means for heating the object 3 to be coated, and includes a case body 19 and three induction coils 20 (20a, 20b, 20c) as shown in FIGS. The case body 19 is formed in a rectangular box shape having an upper wall 22, a bottom wall 23, and an outer peripheral wall 24, and the outer peripheral wall 24 is formed in a rectangular cylindrical shape having front and rear side walls and left and right side walls. Three through-holes 26 (26a, 26b, 26c) penetrating in the vertical direction are provided in the case body 19, and three cylindrical bodies 27 (27a, 27b, 27c) are provided so as to surround the through-hole 26. Have been. The upper end side of the through hole 26 is closed by a lid 28 so as to be openable and closable.
[0014]
The three induction coils 20 are formed in a ring shape, and are incorporated in the case body 19 so as to surround the outer periphery of the through-hole 26 to the cylindrical body 27. They are arranged in an arc so as to correspond to the first heating position B1, the second heating position B2, and the third heating position B3.
Reference numeral 31 denotes an elevating means for elevating and lowering the heating means 18. The elevating means 31 includes a U-shaped support frame 32, a pair of elevating guides 33, and an actuator 34 constituted by an air cylinder. The support frame 32 projects upward from the right end of the support base 11.
[0015]
Each of the pair of elevating guides 33 has a rail body 36 and a pair of upper and lower moving bodies 37, and the rail bodies 36 are fixed vertically on both sides in the width direction of the support frame 32 via support members 38. ing. The pair of upper and lower movable bodies 37 is fixed to a mounting member 39 protruding from the case body 19, and the movable bodies 37 are fitted and held on the rail body 36 so as to be vertically movable. Accordingly, the heating means 18 to the case body 19 are supported by the pair of elevating guides 33 so as to be vertically movable.
The actuator 34 is configured so that the cylinder rod 42 moves up and down from the cylinder main body 41 by supplying and discharging air, the cylinder main body 41 is fixed to the support frame 32 side, and the upper end of the cylinder rod 42 is attached to the mounting body 43. And the heating means 18 to the case body 19 are reciprocated in the vertical direction by the expansion and contraction operation of the actuator 34, whereby the heating means 18 A heating operation position D surrounding the object 3 with the plurality of induction coils 20; and a retreat position E retracting upward from the heating operation position D so that each induction coil 20 is separated from the workpiece 3 at each heating position B. It is movable. Then, when the heating means 18 descends from the retreat position E to the heating operation position D, the object to be coated which is located at each heating position B with respect to each cylindrical body 27 (through hole 26) of the heating means 18 as shown in FIG. 3 are internally fitted from below, and the workpiece 3 at each heating position B is surrounded by a plurality of induction coils 20.
[0016]
A coating means 47 includes a fixing base 48, a support 49, and a coating tool main body 50. The support 49 is projected upward on the fixing base 48, and the coating tool main body 50 has a coating gun 51 and supports the coating tool. The coating tool main body 50 is supported by the body 49 via a rail member 52 so as to be movable up and down. The paint 3 is to be painted. The coating tool main body 50 is reciprocated in the vertical direction by an electric motor for moving the coating tool, not shown. It is designed to be painted over.
[0017]
Reference numeral 55 denotes a rotation driving means for rotating the workpiece 3 at the coating position A, which includes a driving pulley 56, a driven pulley 57, and a V-belt 58. The V belt 58 is wound and pressed against the rotating roller 15 of the holding table 11 at the coating position A, and the driving pulley 56 is rotated by an electric motor (not shown) for rotating the object to be coated. As a result, the holding table 11 at the coating position A is driven to rotate about the vertical support shaft 13. As a result, the workpiece 3 at the coating position A is rotated (rotated) around the support shaft 13, and the coating gun 51 of the coating means 47 uniformly coats the workpiece 3 over the entire circumference. ing.
[0018]
As shown in FIG. 5, a commercial three-phase AC power supply is connected to input terminals R, S, and T of the inverter 61, and a plurality of induction terminals are connected to output terminals U and V of the inverter 61 via an amplifier 63 having a capacitor. The coils 20 (three in the illustrated example) are connected in parallel. The inverter 61 is a general-purpose inverter having a frequency setting device, and converts a three-phase current of a three-phase AC power supply into DC and outputs a single-phase AC current of an arbitrary frequency set by the frequency setting device. For example, the inverter 61 is set to output a low-frequency current of 50 Hz to 60 Hz from the inverter 61. Therefore, low frequency power is supplied from one power source to the induction coil 20 via the inverter 61 and the amplifier 63 to simultaneously heat the plurality of workpieces 3 at the heating position B by low frequency induction heating. ing.
[0019]
The electric motor for driving the rotary table, the actuator 34, the heating means 18, the electric motor for rotating the object to be coated, the electric motor for moving the coating tool, the coating tool main body 50, and the like are interlocked with each other by control means (not shown). The electric motor for driving the rotary table is rotated for several seconds (for example, 6 seconds) every time the rotary table 4 rotates in the circumferential direction at the predetermined interval b as described above. In response to this, when the rotary table 4 intermittently moves in the circumferential direction, the actuator 34 retreats the heating means 18 to the retreat position E and stops the intermittent movement of the rotary table 4. When the heating means 18 is moved to the heating operation position D, the heating means 18 is moved from the heating operation position D to the retreat position in conjunction with the transport means 2 (rotary table 4). It is controlled so as to reciprocate in and.
[0020]
When the heating means 18 moves to the heating operation position D, the heating means 18 causes a low-frequency induction current to flow through each induction coil 20. By passing a low-frequency induction current through the induction coil 20, magnetic lines of force are generated from the induction coil 20 so as to pass through the work 3 at the heating position B, and the work 3 at the heating position B is heated by low-frequency induction heating. Heating.
The electric motor for rotating the workpiece is stopped when the rotary table 4 intermittently moves in the circumferential direction, and is driven when the rotary table 4 stops intermittently moving, so that the workpiece 3 is moved together with the holder 11. It is controlled in conjunction with the transport means 2 (rotary table 4) so as to rotate.
[0021]
The electric motor for moving the coating tool stops driving when the rotary table 4 intermittently moves in the circumferential direction, and when the rotary table 4 stops intermittent movement, the coating tool main body 50 reciprocates in the vertical direction. In addition, it is controlled in conjunction with the transport means 2 (rotary table 4).
Further, when the rotary table 4 intermittently moves in the circumferential direction, the coating tool main body 50 stops operating to stop spraying paint from the coating gun 51, and operates when the rotary table 4 stops intermittent movement. The paint gun 51 is controlled so as to spray paint forward.
[0022]
According to the above-described embodiment, when painting the workpiece 3 such as the piston of the engine, when the power switch is turned on, the turntable 4 intermittently moves in the direction of arrow a, and the turntable 4 moves in the circumferential direction. Since the rotation is stopped for several seconds (for example, 6 seconds) every time the rotation is performed by the predetermined interval b, the workpiece 3 is placed on the holding table 11 on the holding table 11 via the receiving tool 12 on the side farther than the heating position B of the rotary table 4. The work 3 to be coated held on the holding table 11 is intermittently rotated by the rotary table 4, and the first heating position B1, the second heating position B2, the third heating position B3, the soaking position C , And sequentially conveyed to the painting position A. When there is a portion where the object 3 is not painted, a mask may be attached to a portion where the object 3 is not painted.
[0023]
First, when the object 3 is conveyed to the first heating position B1, the heating means 18 descends from the retreat position E to the heating operation position D, and the object 3 is surrounded by the induction coil 20a of the heating means 18. When a low-frequency induction current flows through the induction coil 20a, lines of magnetic force are generated from the induction coil 20a so as to pass through the workpiece 3, and the workpiece 3 is heated by low-frequency induction heating. Next, when the object 3 is conveyed to the second heating position B2, the heating means 18 similarly descends from the retreat position E to the heating operation position D, and passes through the object 3 from the induction coil 20b. The object to be coated 3 is heated by low frequency induction heating. Further, at the third heating position B3, the work 3 is similarly heated by low-frequency induction heating.
[0024]
Accordingly, the workpiece 3 is heated at a low frequency induction at a first heating position B1, a second heating position B2, and a third heating position B3, which are farther than the coating position A, for a predetermined period (for example, 6 seconds), thereby obtaining 110 It is sufficiently heated to a temperature of from ° C to 120 ° C or more.
In this case, when the low-frequency current flows through the plurality of induction coils 20 connected in parallel, the lines of magnetic force are generated from the plurality of induction coils 20 so as to pass through the respective objects 3 to be coated at the heating position B. Can be quickly heated by low-frequency induction heating. Further, the power can be converted into low-frequency power of 50 Hz to 60 Hz from the power supply via the inverter 31 and the output (frequency voltage) of the inverter 61 can be increased by the amplifier 63 having a capacitor. For this reason, the commercial power supply connected to the output terminals R, S, and T sides of the inverter 61 can be increased in output by about 150% by the combination of the inverter 61 and the amplifier 63, and a large energy saving effect can be obtained. . In addition, since a low-frequency current is supplied to a plurality (for example, three) of induction coils 20, a general-purpose inverter 61 having a relatively large capacity is used, and an amplifier 63 having a capacitor having a relatively large capacity is used. Nevertheless, the power factor is very good, the power efficiency is increased, and significant energy saving can be achieved from this point as well.
[0025]
When the workpiece 3 is conveyed to the soaking position C, the first heating position B1, the second heating position B2, and the third heating position during a certain period (for example, 6 seconds) during which the turntable 4 stops. The work 3 to be coated after being heated in B3 is soaked so as to have the same temperature throughout.
Next, when the object 3 is conveyed to the coating position A, the coating is sprayed forward from the coating gun 51 of the coating tool main body 50 to be heated to 110 ° C. to 120 ° C. The painted object 3 is painted. At this time, the coating gun 51 is reciprocated in the vertical direction, and the object 3 at the coating position A is rotated (rotated) around the support shaft 13. The object 3 is evenly applied over the entire circumference.
[0026]
Therefore, for example, as shown in FIG. 2, the worker M is located on the upper side of the heating position B, removes the workpiece 3 painted at the painting position A from the holding table 11, and heats the workpiece 3 before heating. New workpieces 3 may be sequentially held on the holding table 11 conveyed to the worker M side, and the plurality of workpieces 3 are sequentially and efficiently coated after being heated. For this reason, when painting an engine piston or the like with a special coating paint, the object to be coated such as the piston is heated by a heating furnace as in the conventional method, and then the piston is manually removed from the heating furnace and transported by the transportation means. It is not necessary to perform a troublesome operation such as holding the object on the holding stand 11 such as a conveyor, and the object to be coated 3 such as the piston can be heated smoothly, and the coating can be performed simply and efficiently.
[0027]
In the above embodiment, three heating positions B are provided in the transport direction, and the heating means 18 has three induction coils 20 corresponding to the plurality of heating positions B. Instead of providing one, two or four or more heating positions B in the transport direction of the transport means, one or two or four or more induction coils 20 may be provided correspondingly. Good.
In the above-described embodiment, the transport means 2 includes the rotary table 4 and rotates the rotary table 4 intermittently. However, a transport conveyor is used instead of the rotary table 4 and the transport conveyor is used. May be intermittently driven to sequentially transport the plurality of workpieces 3 to the heating position B and the coating position A.
[0028]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, a to-be-painted object, such as a piston, can be heated smoothly, and can be simply and efficiently applied.
[Brief description of the drawings]
FIG. 1 is a front sectional view of a coating apparatus according to an embodiment of the present invention.
FIG. 2 is a plan view of the same.
FIG. 3 is a perspective view of the heating means.
FIG. 4 is a side sectional view of the heating means.
FIG. 5 is an electric circuit diagram of the heating means.
[Explanation of symbols]
2 conveying means 3 object to be coated 4 rotary table 11 holding table 18 heating means 20 induction oil 47 coating means 51 coating gun 55 rotation driving means

Claims

The plurality of objects to be coated (3) are sequentially and intermittently conveyed to the coating position (A) by the conveying means (2), and the object (3) at the coating position (A) is transferred by the coating means (2). In the coating equipment that is to paint sequentially,
A heating position (B) for intermittently transporting the object (3) to be coated is provided on the upper side of the coating position (A), and the object (3) at the heating position (B) is guided by a low-frequency induction. A coating apparatus comprising a heating means (18) for heating by heating.

The heating means (18) has an induction coil (20) formed in an annular shape, and a low-frequency current is applied to the induction coil (20), whereby an object to be coated ( 2. The coating apparatus according to claim 1, wherein 3) is configured to be heated by low-frequency induction heating.

The heating means (18) prevents the induction coil (20) from intermittently moving between the heating operation position (D) surrounding the object (3) at the heating position (B) and the object (3). The coating apparatus according to claim 2, wherein the coating apparatus is movable to a retreat position (E) that retreats from the heating operation position (D) so as not to move.

When the object to be coated (3) is intermittently moved by the conveying means (2), the heating means (18) is retracted to the retreat position (E). When the intermittent movement by the conveying means (2) is stopped, the heating means ( In order to move the heating means (18) to the heating operation position (D), the heating means (18) is reciprocated between the heating operation position (D) and the retreat position (E) in conjunction with the transport means (2). The coating apparatus according to claim 3, wherein the coating apparatus is provided.

The heated workpiece (3) is intermittently transported intermittently between the heating position (B) and the coating location (A) so as to level the workpiece (3). The coating apparatus according to claim 1, wherein a coating is provided.

The plurality of heating positions (B) are provided in the transport direction, and the heating means (18) has a plurality of induction coils (20) corresponding to the plurality of heating positions (B). ), A plurality of induction coils (20) each surrounding a workpiece (3), and a heating operation position (D), and each induction coil (20) includes a workpiece (3) located at each heating position (B). The coating apparatus according to claim 1, wherein the coating apparatus is movable to a retreat position (E) that retreats from the heating operation position (D) so as to deviate.

The conveying means (2) includes a rotary table (4), and the rotary table (4) is provided with a plurality of holding tables (11) for holding the workpieces (3) at predetermined intervals in a circumferential direction, The rotary table (4) rotates intermittently at predetermined intervals in the circumferential direction and intermittently transports the workpiece (3) of the holding table (11) to the heating position (B) and the coating position (A). The coating apparatus according to claim 1, wherein the coating apparatus is configured to perform the coating.

The coating means (47) includes a coating gun (51) for spraying a coating material toward the object (3) at the coating position (A). The coating gun (51) covers the object (3) over a wide area. The coating apparatus according to claim 1, wherein the coating apparatus is reciprocally movable so as to perform the coating over a range.

The coating apparatus according to claim 7, further comprising a rotation driving means (55) for rotating the workpiece (3) at the coating position (A).