JP4032215B2

JP4032215B2 - Electromagnetic induction heating device, fixing device using the same, and image recording device

Info

Publication number: JP4032215B2
Application number: JP2001184809A
Authority: JP
Inventors: 基文馬場
Original assignee: Fuji Xerox Co Ltd; Fujifilm Business Innovation Corp
Current assignee: Fujifilm Business Innovation Corp
Priority date: 2001-06-19
Filing date: 2001-06-19
Publication date: 2008-01-16
Anticipated expiration: 2021-06-19
Also published as: JP2003007445A

Description

【０００１】
【発明の属する技術分野】
本発明は、移動可能な移動被加熱体を電磁誘導発熱作用によって所定の温度に加熱する電磁誘導加熱装置に係り、特に、熱容量の小さい移動被加熱体を用いた態様に有効な電磁誘導加熱装置及びこれを用いた定着装置、画像記録装置の改良に関する。
【０００２】
【従来の技術】
従来より、電磁誘導加熱方式を利用した電磁誘導加熱装置が提案されている。
この電磁誘導加熱装置は、導電性材料からなる電磁誘導発熱層を有する移動被加熱体と、この移動被加熱体に対向配置される励磁コイルを有する加熱装置とを具備するものであり、励磁コイルに交流電圧を印加することで電磁誘導発熱層を貫く変動磁界を生成し、この変動磁界により電磁誘導発熱層内に渦電流を発生させ、電磁誘導発熱層を自己発熱させることで、移動被加熱体と接触する未定着トナー像等を直接加熱させるものである。
【０００３】
この種の電磁誘導加熱装置を定着装置や画像記録装置として利用したものが既に提案されている（例えば特開平１０−３３３４８９号公報，特開平１１−３５２８０４号公報、特開平１１−３５６６４９号公報参照）。
例えば定着装置は、加圧ロールに圧接された定着ベルト（移動被加熱体）に発熱金属体（電磁誘導発熱層）をラミネートし、この定着ベルトの内側に励磁コイルを配設したものである。
そして、この種の定着装置にあっては、励磁コイルに供給する電力は、定着ベルトの温度検出値に基づいて可変制御されるようになっている。
また、画像記録装置は、電磁誘導発熱層を有し且つ未定着像が担持搬送せしめられる像担持搬送体（移動被加熱体）と、この像担持搬送体が局部的に電磁誘導加熱せしめられる励磁コイルを有する加熱装置と、この像担持搬送体の加熱装置に対向する部位の下流位置に配設され且つ像担持搬送体上で溶融した未定着像を記録材上に少なくとも押圧して転写、定着する押圧定着部材とを備えたものである。
【０００４】
【発明が解決しようとする課題】
しかしながら、この種の定着装置や画像記録装置にあっては、熱的な損失を最小限に抑えるという観点から、加熱領域において移動被加熱体（定着ベルトや像担持搬送体）を局部的に電磁誘導加熱する態様が採用されるが、特に、移動被加熱体が例えば熱容量の小さいベルト状であるような場合には、移動被加熱体は非常に高速に加熱が行われて昇温する状況にある。
このような状況において、例えば、移動被加熱体の回転が加熱中に何らかの原因で急激停止した場合や、移動被加熱体の損傷や寿命などによる異常加熱などの状態が起こった場合には、火災の原因となる発火・発煙を引き起こす懸念が考えられる。
このような技術的課題を解決するには、応答性の優れた温度センサを使用して移動被加熱体の温度を迅速に検出し、励磁コイルへの供給電力を制御することが考えられる。
ところが、温度センサの応答性にも限界があり、特に熱容量の小さい移動被加熱体にあっては、急激な温度変化に温度センサが追従するのが極めて困難であり、励磁コイルへの供給電力制御について、温度センサからの情報のみに依存させる態様では、暴走時や故障時における安全性の点で不十分な感は歪めない。
【０００５】
本発明は、以上の技術的課題を解決するためになされたものであって、熱容量の小さい移動被加熱体であっても、安全且つ確実に加熱することを可能とした電磁誘導加熱装置及びこれを用いた定着装置、画像記録装置を提供するものである。
【０００６】
【課題を解決するための手段】
すなわち、本発明は、図１に示すように、移動可能で且つ少なくとも電磁誘導発熱層２を有する移動被加熱体１と、この移動被加熱体１が加熱領域にて局部的に電磁誘導加熱せしめられる励磁コイル４を有する加熱装置３とを備えた電磁誘導加熱装置であって、移動被加熱体１の移動状態を検出する移動検出手段５と、移動被加熱体１の移動方向に対して異なる２箇所の温度を検出する温度検出手段６と、移動検出手段５及び温度検出手段６からの各検出情報を用いて当該各検出情報が予め規定された許容範囲内の場合に励磁コイル４への供給電力量を演算し、演算した供給電力量に基づいて加熱装置３の励磁コイル４への供給電力を制御する供給電力制御手段７とを備えたことを特徴とするものである。
【０００７】
このような技術的手段において、移動被加熱体１は移動して電磁誘導発熱層２を有するものを広く対象とするが、特に熱容量の小さい移動被加熱体１を使用する態様において本件は有効である。
ここで、移動被加熱体１の移動態様としては、代表的には循環回転であるが、一方向移動、往復移動、あるいは、巻き取り移動など各種の態様のものが挙げられる。
また、前記電磁誘導発熱層２については、加熱装置３の励磁コイル４から生成される変動磁界によって渦電流を発生させ、この渦電流によって発熱（ジュール熱）するものであれば、導電性金属を始め適宜選定して差し支えない。
【０００８】
また、加熱装置３は少なくとも変動磁界生成用の励磁コイル４を備えていればよい。
ここで、励磁コイル４としては、交流電圧が印加されたときに変動磁界を生成するものであれば、コイル線材を適宜巻回させる態様でもよいし、予め基準パターン部が繰り返し形成された平板導体を用い、この平板導体の基準パターン部を順次重ね合わせて積層することで平面積層コイルを構成するなど適宜選定して差し支えない。
この場合において、励磁コイル４の取付構造としては台座に保持するなど適宜選定して差し支えなく、また、変動磁界の生成効率を上げるために磁性コアを組み込む等適宜設計変更して差し支えない。
そして、励磁コイル４については、移動被加熱体１の一方の面側に一若しくは複数設けるようにしてもよいし、移動被加熱体１を挟むように複数の励磁コイル４を配設するなど適宜選定して差し支えない。
【０００９】
更に、移動検出手段５は、移動被加熱体１の移動状態を検出できればよく、単に移動の有無のみを検出できるものも含むが、移動被加熱体１の移動状態を正確に検出するという観点からすれば、移動検出手段５は移動被加熱体１の速度を検出する速度検出手段であることが好ましい。
また、温度検出手段６については、移動被加熱体１の温度を検出できれば適宜選定して差し支えないが、移動被加熱体１や温度検出手段６の損傷を有効に防止するという観点からすれば、非接触式温度検出手段６を採用することが好ましい。
ここで、この温度検出手段６は移動被加熱体１の加熱領域での温度状態を把握できればよく、移動被加熱体１の加熱領域に対向した部位に温度検出手段６を配設するようにしてもよいし、あるいは、前記加熱領域を挟んで上流側、下流側に夫々温度検出手段を配設し、両者の温度検出手段により加熱領域の温度情報を把握するようにしてもよい。
【００１０】
また、供給電力制御手段７については、移動被加熱体１の移動、温度情報に基づいて加熱装置３の励磁コイル４への供給電力を制御するものであれば適宜選定して差し支えないが、移動被加熱体１の状態が異常である際には直ちに異常モード処理を実行し、安全性を確保する態様が好ましい。
例えば、供給電力制御手段７は、移動検出手段５及び温度検出手段６からの検出情報が許容条件から逸脱した条件下で移動被加熱体１の状態が異常であると診断する異常診断手段８と、この異常診断手段８が移動被加熱体１の状態を異常であると診断した条件下で加熱装置３の励磁コイル４への供給電力制御を通常モードから異常モードに切換えるモード切換手段９とを備えていることが好ましい。
【００１１】
このような態様において、移動被加熱体１の熱暴走を確実に回避するという観点からすれば、異常診断手段８は少なくとも移動検出手段５にて移動被加熱体１が停止状態にあると検出された条件下で移動被加熱体１の発熱状態が異常であると診断するものであることが好ましい。
このとき、少なくとも移動被加熱体１が停止状態にある条件で移動被加熱体１が発熱状態にある場合、加熱領域で移動被加熱体１が異常昇温する事態であるから、異常であると診断する。
また、モード切換手段９としては、異常診断手段８による異常診断に基づいて通常モードに代えて異常モードを実行するものであればよい。
ここで、異常モードとしては、加熱装置３の励磁コイル４への電力供給を通常モードよりも抑制するものを広く含むが、代表的態様としては、加熱装置３の励磁コイル４への電力供給を遮断する態様が挙げられる。この場合、加熱領域で移動被加熱体１が異常昇温する事態を回避することができる。
【００１２】
また、供給電力制御手段７について、更に安全性を考慮する場合には、適正な供給電力制御が行われているか否かをチェックする態様が好ましい。
この場合の具体的な態様としては、異常診断手段８に、加熱装置３の励磁コイル４への供給電力を検出する供給電力検出手段と、この供給電力検出手段にて検出された供給電力が適正であるかを診断する供給電力診断部とを具備させるようにしてもよい。
また、例えば異常診断手段８に、移動検出手段５及び温度検出手段６にて検出された各検出情報に基づいて加熱装置３の励磁コイル４への供給電力を制御した結果が記憶せしめられる記憶部を設け、この記憶部に記憶されている供給電力の制御結果に基づいて供給電力制御の適正診断を行う供給電力診断部を具備させるようにしてもよい。
【００１３】
また、移動検出手段５及び温度検出手段６からの検出情報は供給電力制御手段７による供給電力制御に使用されるものであるが、これ以外の制御情報として使用することを排除するものではない。
ここでいう供給電力制御以外の制御情報としては、例えば移動被加熱体の寿命や劣化に関する情報が挙げられる。
すなわち、移動被加熱体１の速度と温度が常時検出されているので、移動被加熱体１の寿命や、移動被加熱体１の電磁誘導発熱層２の寿命による回転ムラや温度変化率の異常値なども容易に検出可能である。
【００１４】
更に、本発明は、電磁誘導加熱装置のみならず、これを用いた定着装置をも対象とする。
この場合、本発明は、図１に示すように、循環回転可能で且つ少なくとも電磁誘導発熱層２を有する定着部材（移動被加熱体１に相当）と、この定着部材が加熱領域にて局部的に電磁誘導加熱せしめられる励磁コイル４を有する加熱装置３とを備えた定着装置であって、定着部材の移動状態を検出する移動検出手段５と、定着部材の移動方向に対して異なる２箇所の温度を検出する温度検出手段６と、移動検出手段５及び温度検出手段６からの各検出情報を用いて当該各検出情報が予め規定された許容範囲内の場合に励磁コイル４への供給電力量を演算し、演算した供給電力量に基づいて加熱装置３の励磁コイル４への供給電力を制御する供給電力制御手段７とを備えたことを特徴とするものである。
【００１５】
また、本発明は、電磁誘導加熱装置を用いた画像記録装置をも対象とする。
この場合、本発明は、図１に示すように、少なくとも電磁誘導発熱層２を有し且つ未定着像が担持搬送せしめられる像担持搬送体（移動被加熱体１に相当）と、この像担持搬送体が局部的に電磁誘導加熱せしめられる励磁コイル４を有する加熱装置３と、この像担持搬送体の加熱装置３に対向する部位の下流位置に配設され且つ像担持搬送体上で溶融した未定着像を記録材上に少なくとも押圧して転写、定着する押圧定着部材とを備えた画像記録装置において、像担持搬送体の移動状態を検出する移動検出手段５と、像担持搬送体の移動方向に対して異なる２箇所の温度を検出する温度検出手段６と、移動検出手段５及び温度検出手段６からの各検出情報を用いて当該各検出情報が予め規定された許容範囲内の場合に励磁コイル４への供給電力量を演算し、演算した供給電力量に基づいて加熱装置３の励磁コイル４への供給電力を制御する供給電力制御手段７とを備えたことを特徴とするものである。
【００１６】
【発明の実施の形態】
◎実施の形態１
図２は本発明に係る電磁誘導加熱装置を利用した定着装置の実施の形態１を示す。
同図において、本実施の形態に係る定着装置２０は、一対の張架ロール２１，２２間に定着ベルト３０を循環回転可能に張架し、一方の張架ロール２１を駆動ロールとして矢印方向に循環回転するものであり、前記他方の張架ロール２２をバックアップロールとして定着ベルト３０に加圧ロール２３を圧接配置し、この定着ベルト３０のうち前記加圧ロール２３とバックアップロール２２との定着ニップ域を定着領域Ｙとして形成し、この定着領域Ｙの上流側に位置する定着ベルト３０部分を加熱装置４０による加熱領域Ｘとして形成したものである。
【００１７】
本実施の形態において、定着ベルト３０としては、例えば図３に示すように、耐熱性の高いシート状部材からなる基層３０ａと、その上に積層された電磁誘導発熱層（導電層）３０ｂと、最も上層となる表面離型層３０ｃとの３層を基本的に備えていることが好ましい。
ここで、基層３０ａとしてはポリイミド、ポリアミド、ポリイミドアミド等に代表される耐熱性の高い樹脂が用いられており、例えば２０〜８０μｍの厚さのものが使用される。
また、電磁誘導発熱層３０ｂとしては、電磁誘導加熱作用により自己発熱するものであれば適宜選定し得るものであり、本実施の形態では、例えば電磁誘導発熱層３０ｂの厚さは１μｍ〜２０μｍで、固有抵抗値が２．７×１０^-8Ωｍ以下の電気良導電性材料からなり、渦電流損により発熱を生じさせるものが用いられる。
本実施の形態における電磁誘導発熱層３０ｂとしては、例えば銅、銀、アルミニウム又はこれに相当する耐熱性有機導電体などが挙げられる。
特に、固有抵抗値や熱効率の点、電磁誘導発熱層３０ｂとしての製造容易性（エッチング処理の容易性など）、さらには、コストの面などを考慮すると、銅は最適である。
【００１８】
更に、表面離型層３０ｃとしては、離型性の高いシート又はコート層であることが好ましく、例えばフッ素樹脂、シリコーン樹脂、フルオロシリコーンゴム、フッ素ゴム、シリコーンゴム、ＰＦＡ、ＰＴＦＥ、ＦＥＰなどが用いられる。特に、表面離型層３０ｃの材料を弾性材料で構成する場合には、トナーを包み込むような状態で密着するため、画像の劣化が少なく画像光沢が均一になる点で好ましい。
尚、表面離型層３０ｃと電磁誘導発熱層３０ｂとの間に弾性層や抵抗調整層などの中間層（図示せず）を介在させるようにしてもよい。
【００１９】
また、加熱装置４０は、定着ベルト３０を移動被加熱体とし、この定着ベルト３０を加熱領域Ｘにて電磁誘導発熱させるためのものである。
本実施の形態において、加熱装置４０は、例えば図２及び図３に示すように、定着ベルト３０の内側に配設されており、定着ベルト３０の搬送方向に直交する幅方向に沿って配設される非磁性の長尺な板状の台座４１と、この台座４１内に形成される凹部の中央に配設されるフェライト等の磁性コア４２と、この磁性コア４２に巻き回されて定着ベルト３０の厚さ方向に向かって変動磁界Ｈを生成する励磁コイル４３とを備え、電源４４にて励磁コイル４３に給電することにより定着ベルト３０の電磁誘導発熱層３０ｂの厚さ方向を貫くように変動磁界Ｈを生成し、前記電磁誘導発熱層３０ｂに渦電流Ｉｃを生じさせ、電磁誘導発熱層３０ｂを発熱させるものである。
【００２０】
更に、本実施の形態では、定着ベルト３０のうち駆動ロール２１の直前上流側部分に対応した箇所には速度センサ５０が配設されている。
この速度センサ５０は例えば光学式センサにて構成されており、定着ベルト３０に付されたマーカ（ラダーマークや孔）などを光学的に検出することで定着ベルト３０の速度を検出するようになっている。
【００２１】
一方、本実施の形態では、定着ベルト３０の加熱領域Ｘの直前、直後に対応して温度センサ５１，５２が配設されている。
この温度センサ５１，５２としては定着ベルト３０の外側に非接触配置される非接触型温度センサ（例えば赤外線放射型センサなど）が用いられる。
特に、本実施の形態では、供給される電力量が加熱領域Ｘの直前、直後の温度差と加熱領域Ｘの熱容量とにより演算可能であることに着目し、温度センサ５１，５２からの温度情報は供給される電力量を演算する上で用いられる。
【００２２】
更に、本実施の形態では、制御装置６０は、速度センサ５０，温度センサ５１，５２からの検出信号を取り込み、例えば図４に示すような励磁コイル４３への供給電力制御を行い、加熱装置４０の電源４４に所定の制御信号を送出するようになっている。
尚、制御装置６０は、図４に示すような制御処理の他に各種の制御処理、例えば定着ベルト３０の駆動制御処理、具体的には、画像形成用のスタートスイッチからのスタート信号に同期して所定のタイミングで駆動モータ２１ａを駆動し、この駆動モータ２１ａに駆動連結された駆動ロール２１を介して定着ベルト３０を駆動回転する処理を行うようになっている。
【００２３】
次に、本実施の形態に係る定着装置の作動について説明する。
今、本実施の形態に係る定着装置を組み込んだ画像形成装置において、図示外のスタートスイッチをオン操作すると、制御装置６０は所定のタイミングで駆動モータ２１ａの駆動を開始し、定着ベルト３０を駆動回転する。
この状態において、制御装置６０は、図４に示す励磁コイルへの供給電力制御処理を実行する。
そして、定着ベルト３０が劣化などなく正常回転している条件下では、制御装置６０は後述する通常モード処理を行い、加熱装置４０の電源４４に所定の制御信号を送出し、加熱装置４０の励磁コイル４３に所定の電力を供給する。
すると、加熱装置４０が定着ベルト３０を電磁誘導加熱するため、定着ベルト３０が加熱領域Ｘにて局部的に加熱されることになり、加熱された定着ベルト３０が定着領域Ｙへと移動する。
一方、この定着領域Ｙには、例えば未定着トナー像２７を担持した記録シート２６が所定のタイミングで搬送されてくるため、加圧ロール２３と加熱された定着ベルト３０とによって記録シート２６上の未定着トナー像は加熱、加圧定着される。
【００２４】
ここで、図４に示す励磁コイルへの供給電力制御処理について詳述する。
図４において、制御装置６０は、移動被加熱体である定着ベルト３０の速度チェックを行う。
この速度チェックは、図５に示すように、速度センサ５０にて定着ベルト３０の速度を常時検出し、先ず、検出信号出力の有無をチェックし、検出信号出力がなければ直ちに異常モードに移行し、検出信号出力があれば、その速度検出値が異常値であるか否かをチェックする。
そして、速度検出値が異常値であれば異常モードに移行し、一方、異常値でなければ、速度検出値が許容範囲内か否かをチェックした後、許容範囲内であれば通常モードに移行し、許容範囲外であれば、定着ベルト３０の搬送エラー、寿命警告を行う。
【００２５】
また、図４において、制御装置６０は、移動被加熱体である定着ベルト３０の温度チェックを行う。
この温度チェックは、図６に示すように、温度センサ５１，５２にて定着ベルト３０の加熱領域Ｘ前後の温度を常時検出し、先ず、検出信号出力の有無をチェックし、検出信号出力がなければ直ちに異常モードに移行し、検出信号出力があれば、その温度検出値が異常値であるか否かをチェックする。
そして、温度検出値が異常値であれば異常モードに移行し、一方、異常値でなければ、温度検出値が許容範囲内か否かをチェックした後、許容範囲内であれば通常モードに移行し、許容範囲外であれば、定着ベルト３０の加熱エラー、寿命警告を行う。
【００２６】
この後、制御装置６０は、速度チェック及び温度チェックに基づいて、異常モード処理あるいは通常モード処理を実行する。
ここで、異常モード処理としては、図７（ａ）に示すように、励磁コイル４３への電力供給を遮断した後、検出センサエラー又はシステムエラー警告を行う。
一方、通常モード処理としては、図７（ｂ）に示すように、速度検出値、温度検出値、及び、予め選定されている定着ベルト３０の熱容量より最適な供給電力量を演算する。
特に、本例では、定着ベルト３０のうち、加熱領域Ｘの前後の温度を検出することで加熱領域Ｘにおける温度変化を予測し、これに基づいて供給電力を演算するようになっている。
この供給電力量の演算が終了すると、励磁コイル４３への電力供給準備が行われ、しかる後に、励磁コイル４３への電力供給が開始される。
【００２７】
このような動作過程において、例えば定着ベルト３０が急に停止したような状況を想定して見ると、定着ベルト３０の速度チェックにより異常モードに移行するため、直ちに異常モード処理が行われ、加熱装置４０による加熱動作が停止される。
このため、加熱領域Ｘにおいて、停止した定着ベルト３０が加熱装置４０による電磁誘導発熱することはなくなり、定着ベルト３０が異常昇温する事態は有効に回避される。
【００２８】
また、定着ベルト３０の電磁誘導発熱層３０ｂが劣化したような状況を想定して見ると、定着ベルト３０の温度チェックにより定着ベルト３０の状態が把握される。
例えば定着ベルト３０の劣化の程度が未だ軽度である場合には、定着ベルト３０の加熱エラー、寿命警告が行われ、一方、定着ベルト３０の劣化の程度が交換を要する程度に重度である場合には異常モードに移行し、異常モード処理が行われる。
これらの動作過程は、例えば後述する実施例にて裏付けられる。
【００２９】
また、励磁コイル４３への供給電力制御については、上述したものに限られるものではなく、供給される電力量をチェックし、更に、安全性を高めるようにしてもよい。
例えば図４の励磁コイル４３への供給電力制御処理において、通常モード処理を図８のように構築してもよい。
すなわち、図８に示すように、励磁コイル４３への供給電力（具体的には電流値）を検出し、この検出値が許容範囲内か否かをチェックし、許容範囲内であれば、励磁コイルへの供給電力を継続して行い、一方、許容範囲外であれば、定着ベルト３０の加熱エラー、寿命警告を行った後、異常モード処理を行う。
【００３０】
更に、例えば図４の励磁コイル４３への供給電力制御処理において、通常モード処理を図９のように構築してもよい。
すなわち、図９に示すように、速度検出値、温度検出値、及び、予め選定されている定着ベルト３０の熱容量より最適な供給電力量を演算し、この演算された供給電力をメモリに記憶し、この供給電力が異常か否かをチェックする。
そして、演算された供給電力が異常であれば、定着ベルト３０の加熱エラー、寿命警告をした後、異常モード処理を実行する。
一方、演算された供給電力が異常でなければ、励磁コイル４３への電力供給準備が行われ、しかる後に、励磁コイル４３への電力供給が開始される。
【００３１】
◎実施の形態２
図１０は本発明に係る電磁誘導加熱装置を利用した定着装置の実施の形態２を示す。
同図において、定着装置２０は、チューブ状の定着ベルト７１と加圧ロール７２とを互いに圧接配置し、定着ベルト７１と加圧ロール７２との定着ニップ域に対応した定着ベルト７１内には弾性パッド７３（熱容量の小さい支持ホルダ７３ａに弾性層７３ｂを設けた態様）を配設するようにしたものである。
本実施の形態では、加圧ロール７２が図示外の駆動源にて駆動されるようになっており、この加圧ロール７２からの駆動力によって定着ベルト７１が従動回転するようになっている。
尚、符号７５は加圧ロール７２の表面に付設される金属ロールであり、加圧ロール７２の軸方向温度を均一に保ち、かつ、加圧ロール７２表面を清掃するクリーニング部材としても機能するようになっている。
【００３２】
本実施の形態において、定着ベルト７１は、実施の形態１の定着ベルト３０と同様に、基層、電磁誘導発熱層及び表面離型層の３層を基本的に備えている。
また、定着ベルト７１の定着ニップ域の反対側部分の外側には、定着ベルト７１を電磁誘導発熱させるための加熱装置８０が配設されている。
本実施の形態において、加熱装置８０は、図１０に示すように、定着ベルト７１の外側に定着ベルト７１の湾曲形状に対応した形状をもって配設されており、定着ベルト７１の搬送方向に直交する幅方向に沿って配設される非磁性の長尺な板状の台座８１と、この台座８１内に形成される凹部の中央に配設されるフェライト等の磁性コア８２と、この磁性コア８２に巻き回されて定着ベルト７１の厚さ方向に向かって変動磁界を生成する励磁コイル８３とを備え、図示外の電源にて励磁コイル８３に給電することにより定着ベルト７１の電磁誘導発熱層の厚さ方向を貫くように変動磁界を生成し、前記電磁誘導発熱層に渦電流を生じさせ、電磁誘導発熱層を発熱させるものである。
尚、符号８５は台座８１の外側に向かう磁場を遮蔽する磁場遮蔽板である。
【００３３】
更に、本実施の形態において、定着ベルト７１の周囲のうち、定着ニップ域の上流側には速度センサ９０が配設されており、また、加熱装置８０による加熱領域の前後には温度センサ９１，９２が配設されており、これらのセンサ９０〜９２出力は図示外の制御装置に取り込まれ、例えば図４（図５〜図７）あるいはこれの変形形態（図８，図９）に相当する励磁コイルへの供給電力制御処理が行われ、加熱装置８０の電源（図示せず）に所定の制御信号が送出されるようになっている。
【００３４】
次に、本実施の形態に係る定着装置の作動について説明する。
今、図１０において、図示外のスタートスイッチをオンすると、所定のタイミングで加圧ロール７２が駆動回転され、定着ベルト７１が追従回転する。
このとき、図４に示すような励磁コイルへの供給電力制御処理が行われ、定着ベルト７１が劣化などなく正常に回転している条件下では、通常モード処理が行われ、定着ベルト７１は加熱装置８０にて局部的に電磁誘導加熱された後、定着ニップ域へと移動し、一方、未定着トナー像２７を担持した記録シート２６も定着ニップ域へと所定のタイミングで搬送され、定着ニップ域にて熱と加圧による所定の定着動作が行われる。
【００３５】
このような動作過程において、速度センサ９０による速度チェックと、温度センサ９１，９２による温度チェックとが並列に行われるため、仮に、速度チェックあるいは温度チェックで、異常モードに移行した際には、直ちに異常モード処理が行われる。
それゆえ、例えば定着ベルト７１が何らかの理由により停止したような場合には、温度チェックにより異常モードに移行するため、直ちに異常モード処理（本例では励磁コイル８３への供給電力を遮断）が実行され、定着ベルト７１の異常昇温などの不具合は有効に回避される。
また、定着ベルト７１が劣化したような場合でも、その劣化の程度に応じて異常モード処理が行われたり、あるいは、所定の警告表示が行われる。
【００３６】
◎実施の形態３
図１１は本発明に係る電磁誘導加熱装置を利用した画像記録装置の実施の形態３を示す。
同図において、この画像記録装置は、例えば二つの張架ロール１０１，１０２に掛け渡されて周面が周回移動する中間転写ベルト１００を備えており、この中間転写ベルト１００と対向する位置に、夫々イエロ、マゼンタ、シアン、ブラックのトナー像が形成せしめられる四つの作像ユニット１１０（１１０Ｙ，１１０Ｍ，１１０Ｃ，１１０Ｋ）を配設したものである。
ここで、各作像ユニット１１０（１１０Ｙ〜１１０Ｋ）は、例えば表面に静電潜像が形成される感光体ドラム１１１と、感光体ドラム１１１表面を略一様に帯電する帯電装置１１２と、感光体ドラム１１１上にレーザ光を照射して潜像を形成する露光装置１１３と、感光体ドラム１１１上の潜像にトナーを選択的に転移させてトナー像を形成する現像装置１１４とを備えている。
尚、符号１１５は中間転写ベルト１００を挟んで感光体ドラム１１１と対向するように配置され、感光体ドラム１１１と中間転写ベルト１００との間に所定の転写ニップ域を形成する対向ロール、１１６は中間転写ベルト１００を介して感光体ドラム１１１上の各色トナー像が中間転写ベルト１００側に一次転写せしめられる転写バイアスを印加するバイアスロール、１１７は転写バイアス電源である。
【００３７】
更に、本実施の形態において、画像記録装置は、発熱可能な中間転写ベルト１００と、この中間転写ベルト１００を転写定着領域Ｚ（本例では張架ロール１０１部位）前の加熱領域Ｘにて加熱する加熱装置１２０と、中間転写ベルト１００の転写定着領域Ｚにて張架ロール１０１に対向配置されて中間転写ベルト１００を押圧する押圧定着ロール１３０とを備えている。
ここで、中間転写ベルト１００は、例えば図１１に示すように、ポリイミド、ポリアミド、ポリイミドアミド等の耐熱性の高い樹脂からなる基層１００ａと、その上に積層された電磁誘導発熱層（導電層）１００ｂと、最も上層となる離型性の高いフッ素樹脂、シリコーン樹脂等の表面離型層１００ｃとの３層を基本的に備えている。
尚、本実施の形態では、電磁誘導発熱層１００ｂは一部基層１００ａ側に露出配置されており、前記バイアスロール１１６と中間転写ベルト１００の電磁誘導発熱層１００ｂとが常時接触配置されるようになっている。
【００３８】
また、加熱装置１２０は、実施の形態１と略同様に、中間転写ベルト１００の内側に配設されており、中間転写ベルト１００の搬送方向に直交する幅方向に沿って配設される非磁性の長尺な板状の台座（図示せず）と、この台座内に形成される凹部の中央に配設されるフェライト等の磁性コア（図示せず）と、この磁性コアに巻き回されて中間転写ベルト１００の厚さ方向に向かって変動磁界を生成する励磁コイル（図示せず）とを備え、電源１２４にて励磁コイルに給電することにより変動磁界を生成し、中間転写ベルト１００の電磁誘導発熱層１００ｂに渦電流を生じ、電磁誘導発熱層１００ｂを発熱させるものである。
【００３９】
更に、このような画像記録装置において、本実施の形態では、中間転写ベルト１００の内側に例えば速度センサ１４０が配設されており、中間転写ベルト１００の加熱装置１２０による加熱領域前後に温度センサ１４１，１４２が配設されている。これらのセンサ１４０〜１４２出力は図示外の制御装置に取り込まれ、図４（図５〜図７）あるいはこれの変形形態（図８，図９）に相当する励磁コイルへの供給電力制御処理が行われ、加熱装置１２０の電源１２４に所定の制御信号が送出されるようになっている。
【００４０】
次に、本実施の形態に係る画像記録装置の作動について説明する。
図１１に示すように、各作像ユニット１１０（１１０Ｙ〜１１０Ｋ）により、感光体ドラム１１１上にそれぞれ異なる色のトナー像が形成される。
一方、中間転写ベルト１００は一定方向に循環移動しており、各作像ユニット１１０の一次転写部にはバイアスロール１１６からの一次バイアスが作用し、感光体ドラム１１１上のトナー像が中間転写ベルト１００上に転写される。
そして、四つの作像ユニット１１０からトナー像が順次転写された後、重ね合わされた四色のトナー像Ｔは中間転写ベルト１００の移動により加熱装置１２０と対向する加熱領域Ｘに搬送される。
【００４１】
この加熱領域Ｘでは、中間転写ベルト１００上の四色のトナー像が、電磁誘導加熱により電磁誘導発熱層１００ｂの発熱により溶融される。
この後、溶融したトナー像Ｔは転写定着領域Ｚにて押圧定着ロール１３０の押圧作用により室温の記録シート２６と圧接され、トナー像Ｔが記録シート２６に浸透して転写定着されると共に、トナー像Ｔは定着ニップ域の出口側に向かって搬送される間に冷却される。定着ニップ域の出口では、トナーの温度は充分に低くなっており、トナーの凝集力が大きいため、オフセットを生ずることなく、トナー像はそのまま略完全に記録シート２６上に転写定着される。
【００４２】
このような動作過程において、速度センサ１４０による速度チェックと、温度センサ１４１，１４２による温度チェックとが並列に行われるため、仮に、速度チェックあるいは温度チェックで、異常モードに移行した際には、直ちに異常モード処理が行われる。
それゆえ、例えば中間転写ベルト１００が何らかの理由により停止したような場合には、温度チェックにより異常モードに移行するため、直ちに異常モード処理（本例では励磁コイルへの供給電力を遮断）が実行され、中間転写ベルト１００の異常昇温などの不具合は有効に回避される。
また、中間転写ベルト１００が劣化したような場合でも、その劣化の程度に応じて異常モード処理が行われたり、あるいは、所定の警告表示が行われる。
【００４３】
【実施例】
◎実施例１
本実施例は実施の形態１に係る定着装置モデルを具体化したものであり、励磁コイル４３に供給する電力は１００〜１０００Ｗとし、定着ベルト３０の周速度は７０〜２００ｍｍ／ｓｅｃとした。
また、励磁コイル４３に電力を供給する電源４４は高周波インバーター電源で、交流周波数は２０〜１００ｋＨｚである。
更に、本実施例で使用した定着ベルト３０は図３に示すような構造を有し、厚さ２０〜８０μｍのポリイミド基層３０ａ、厚さ１〜２０μｍの銅の電磁誘導発熱層３０ｂ、１０〜５０μｍの表面離型層３０ｃからなり、総厚さがおよそ１００μｍ程度になるように成形したものである。
また、速度センサ５０及び温度センサ５１，５２はそれぞれ非接触で測定可能な光学式センサ、赤外線放射型センサを採用した。
【００４４】
以上の構成を有する定着装置において次のような実験を行った。
この実験は計１２時間連続で行い、信頼性も確認するため継続して計１２時間の実験を数十回繰り返して行ったものである。
▲１▼ 連続で定着運転
▲２▼ ５、１０ｓｅｃ毎に定着運転
▲３▼ ▲１▼及び▲２▼の状態中に定着ベルトに負荷をかけて定着ベルトの速度を低下または停止させる条件
▲４▼ 定着ベルトに損傷を与え、▲１▼及び▲２▼の状態で運転する条件
▲５▼ 供給すべき電力量よりも大きいまたは小さい（許容範囲外）電力を供給する条件
▲６▼ 速度センサ５０及び温度センサ５１，５２に測定値とは異なった値を出力させる条件
【００４５】
本実験では、初期的に速度および温度センサの故障時想定のテストは予め行っており、制御システムが正常に動作していることを確認している。
上記実験の結果、定着装置はすべての条件において安全な状態が確保され、火災の原因となる現象（発火、発煙等）は未然に防ぐことができた。
また、本実験後の影響による定着装置の異常は認められず、その後も正常な運転が可能であったことから、熱損傷破壊に至るような定着ベルト３０（移動被加熱体）の暴走を生じさせることなく安全な装置とすることができた。
【００４６】
【発明の効果】
以上説明してきたように、本発明に係る電磁誘導加熱装置によれば、移動被加熱体の移動情報及び温度情報を夫々検出し、各検出情報に基づいて加熱装置の励磁コイルへの供給電力制御を行うようにしたので、移動被加熱体の状況（移動、温度）を正確に把握することができ、供給電力制御を安全に実現することができる。
このため、移動被加熱体の熱暴走を未然に防止することが可能になり、装置の熱損傷や熱破壊を有効に防止し、安全性及び信頼性の高い装置を提供することができる。
また、このような電磁誘導加熱装置を用いた定着装置、画像記録装置によれば、移動被加熱体の熱暴走を未然に防止することができるため、この移動被加熱体を用いた定着動作や画像記録動作を安全且つ確実に実現することができる。
【図面の簡単な説明】
【図１】本発明に係る電磁誘導加熱装置の概要を示す説明図である。
【図２】実施の形態１に係る定着装置の全体構成を示す説明図である。
【図３】実施の形態１で用いられる定着ベルト及び加熱装置の構成例を示す説明図である。
【図４】実施の形態１で用いられる励磁コイルへの供給電力制御の処理例を示すフローチャートである。
【図５】図４の「移動被加熱体の速度チェック」の処理例を示すフローチャートである。
【図６】図４の「移動被加熱体の温度チェック」の処理例を示すフローチャートである。
【図７】（ａ）は異常モード処理例を示すフローチャート、（ｂ）は通常モード処理例を示すフローチャートである。
【図８】通常モード処理の他の例を示すフローチャートである。
【図９】通常モード処理の更に別の例を示すフローチャートである。
【図１０】実施の形態２に係る定着装置の全体構成を示す説明図である。
【図１１】実施の形態３に係る画像記録装置の全体構成を示す説明図である。
【符号の説明】
１…移動被加熱体，２…電磁誘導発熱層，３…加熱装置，４…励磁コイル，５…移動検出手段，６…温度検出手段，７…供給電力制御手段，８…異常診断手段，９…モード切換手段[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electromagnetic induction heating apparatus that heats a movable object to be moved to a predetermined temperature by electromagnetic induction heat generation, and more particularly to an electromagnetic induction heating apparatus that is effective for an embodiment using a movable object to be heated having a small heat capacity. The present invention also relates to improvement of a fixing device and an image recording apparatus using the same.
[0002]
[Prior art]
  Conventionally, an electromagnetic induction heating apparatus using an electromagnetic induction heating method has been proposed.
  This electromagnetic induction heating device includes a moving heated body having an electromagnetic induction heat generating layer made of a conductive material, and a heating device having an exciting coil disposed opposite to the moving heated body. By applying an AC voltage toelectromagneticGenerates a fluctuating magnetic field that penetrates the induction heat generation layer, generates an eddy current in the electromagnetic induction heat generation layer by the fluctuating magnetic field, and self-heats the electromagnetic induction heat generation layer, so that an unfixed toner image that contacts the moving heated object Is heated directly.
[0003]
Devices using this type of electromagnetic induction heating device as a fixing device or an image recording device have already been proposed (see, for example, Japanese Patent Laid-Open Nos. 10-333489, 11-352804, and 11-356649). ).
For example, in a fixing device, a heat generating metal body (electromagnetic induction heat generating layer) is laminated on a fixing belt (moving object to be heated) pressed against a pressure roll, and an exciting coil is disposed inside the fixing belt.
In this type of fixing device, the electric power supplied to the exciting coil is variably controlled based on the temperature detection value of the fixing belt.
In addition, the image recording apparatus has an electromagnetic induction heating layer and an image carrier (movable body to be heated) on which an unfixed image is carried and conveyed, and an excitation in which the image carrier is locally heated by electromagnetic induction. A heating device having a coil, and an unfixed image disposed on the downstream side of the portion of the image carrier carrying member facing the heating device and melted on the image carrier carrier is at least pressed onto the recording material for transfer and fixing. And a pressing and fixing member.
[0004]
[Problems to be solved by the invention]
However, in this type of fixing device and image recording device, from the viewpoint of minimizing thermal loss, the moving object to be heated (fixing belt or image carrier) is locally electromagnetic in the heating region. Although the mode of induction heating is adopted, especially when the moving object to be heated is, for example, in the form of a belt having a small heat capacity, the moving object to be heated is heated at a very high speed. is there.
In such a situation, for example, if the rotation of the moving heated object suddenly stops for some reason during heating, or if abnormal conditions such as damage or life of the moving heated object occur, a fire There is a concern that it may cause fire and smoke.
In order to solve such a technical problem, it is conceivable to quickly detect the temperature of the moving object to be heated and control the power supplied to the exciting coil by using a temperature sensor having excellent responsiveness.
However, there is a limit to the responsiveness of the temperature sensor, and it is extremely difficult for the temperature sensor to follow a rapid temperature change, especially for a moving heated object with a small heat capacity. In the aspect of relying only on information from the temperature sensor, an insufficient feeling in terms of safety during runaway or failure will not be distorted.
[0005]
The present invention has been made to solve the above technical problems, and an electromagnetic induction heating apparatus capable of safely and surely heating even a moving heated object having a small heat capacity, and the same The present invention provides a fixing device and an image recording apparatus using the above-described printer.
[0006]
[Means for Solving the Problems]
  That is, as shown in FIG. 1, in the present invention, a movable heated body 1 that is movable and has at least an electromagnetic induction heating layer 2 and the movable heated body 1 are locally heated by electromagnetic induction heating in a heating region. Excitation coil4An electromagnetic induction heating device having a heating device 3 having a movement detecting means 5 for detecting the movement state of the moving heated body 1 and two temperatures different with respect to the moving direction of the moving heated body 1 Temperature detection means 6 for detecting the movement, and each detection information from the movement detection means 5 and the temperature detection means 6Is used to calculate the amount of power supplied to the exciting coil 4 when the detected information is within a predetermined allowable range.And a supply power control means 7 for controlling the supply power to the excitation coil 4 of the heating device 3.
[0007]
In such technical means, the moving heated object 1 is widely intended to move and have the electromagnetic induction heat generating layer 2, but this case is particularly effective in an embodiment using the moving heated object 1 having a small heat capacity. is there.
Here, as a movement mode of the moving heated object 1, although it is typically a circular rotation, there are various modes such as a one-way movement, a reciprocating movement, and a winding movement.
For the electromagnetic induction heat generating layer 2, if an eddy current is generated by a fluctuating magnetic field generated from the excitation coil 4 of the heating device 3 and heat is generated by this eddy current (Joule heat), a conductive metal is used. It may be selected appropriately at the beginning.
[0008]
The heating device 3 only needs to include at least the exciting coil 4 for generating a variable magnetic field.
Here, as the exciting coil 4, a coil wire may be appropriately wound as long as it generates a variable magnetic field when an AC voltage is applied, or a flat conductor in which a reference pattern portion is repeatedly formed in advance. The reference pattern portions of the flat conductors may be stacked one on top of the other so as to form a planar laminated coil.
In this case, the mounting structure of the exciting coil 4 may be appropriately selected such as being held on a pedestal, or may be appropriately changed in design such as incorporating a magnetic core in order to increase the generation efficiency of the variable magnetic field.
One or a plurality of exciting coils 4 may be provided on one surface side of the moving heated body 1, or a plurality of exciting coils 4 may be provided so as to sandwich the moving heated body 1. You can choose.
[0009]
  Further, the movement detection means 5 only needs to be able to detect the movement state of the moving heated body 1 and includes only one that can detect only the presence or absence of movement, but from the viewpoint of accurately detecting the moving state of the moving heated body 1. In this case, the movement detection means 5 is preferably a speed detection means for detecting the speed of the moving heated body 1.
  Further, the temperature detection means 6 may be appropriately selected as long as the temperature of the moving heated body 1 can be detected, but from the viewpoint of effectively preventing the moving heated body 1 and the temperature detecting means 6 from being damaged,Non-contactIt is preferable to employ the formula temperature detection means 6.
  Here, the temperature detecting means 6 only needs to be able to grasp the temperature state in the heating area of the moving heated body 1, and the temperature detecting means 6 is disposed at a portion facing the heating area of the moving heated body 1. Alternatively, temperature detection means may be provided on the upstream side and the downstream side of the heating area, respectively, and the temperature information of the heating area may be grasped by both temperature detection means..
[0010]
The supply power control means 7 may be appropriately selected as long as it controls the power supplied to the exciting coil 4 of the heating device 3 based on the movement and temperature information of the moving body 1 to be heated. When the state of the to-be-heated body 1 is abnormal, an abnormal mode process is immediately executed to ensure safety.
For example, the supply power control means 7 includes an abnormality diagnosis means 8 for diagnosing that the state of the moving heated body 1 is abnormal under the condition that the detection information from the movement detection means 5 and the temperature detection means 6 deviates from the allowable condition. The mode switching means 9 for switching the control of the power supplied to the exciting coil 4 of the heating device 3 from the normal mode to the abnormal mode under the condition that the abnormality diagnosis means 8 diagnoses the state of the moving heated body 1 as abnormal. It is preferable to provide.
[0011]
In such a mode, from the viewpoint of surely avoiding the thermal runaway of the moving heated object 1, the abnormality diagnosis means 8 is detected by at least the movement detecting means 5 that the moving heated object 1 is in a stopped state. It is preferable to diagnose that the heat generation state of the moving heated body 1 is abnormal under the above conditions.
At this time, if the moving heated body 1 is in a heat generation state at least under the condition that the moving heated body 1 is in a stopped state, the moving heated body 1 is abnormally heated in the heating region. Diagnose.
The mode switching unit 9 may be any unit that executes the abnormal mode instead of the normal mode based on the abnormality diagnosis by the abnormality diagnosing unit 8.
Here, the abnormal mode widely includes those in which the power supply to the excitation coil 4 of the heating device 3 is suppressed more than in the normal mode, but as a typical mode, the power supply to the excitation coil 4 of the heating device 3 is included. The aspect which interrupts | blocks is mentioned. In this case, it is possible to avoid a situation in which the temperature of the moving heated body 1 is abnormally increased in the heating region.
[0012]
Further, in the case of considering further safety with respect to the supply power control means 7, it is preferable to check whether proper supply power control is being performed.
As a specific mode in this case, the abnormality diagnosis means 8 is appropriately supplied power detection means for detecting the supply power to the excitation coil 4 of the heating device 3 and the supply power detected by the supply power detection means. And a supply power diagnosis unit for diagnosing whether or not.
Further, for example, a storage unit in which the abnormality diagnosis unit 8 stores the result of controlling the power supplied to the excitation coil 4 of the heating device 3 based on each detection information detected by the movement detection unit 5 and the temperature detection unit 6. And a supply power diagnosis unit that performs appropriate diagnosis of the supply power control based on the control result of the supply power stored in the storage unit.
[0013]
The detection information from the movement detection means 5 and the temperature detection means 6 is used for supply power control by the supply power control means 7, but it is not excluded to use it as other control information.
As control information other than supply power control here, the information regarding the lifetime and deterioration of a moving to-be-heated body is mentioned, for example.
That is, since the speed and temperature of the moving heated body 1 are always detected, the rotation unevenness due to the life of the moving heated body 1, the life of the electromagnetic induction heating layer 2 of the moving heated body 1, and the temperature change rate abnormality The value can also be easily detected.
[0014]
  Furthermore, the present invention is directed to not only an electromagnetic induction heating device but also a fixing device using the same.
  In this case, as shown in FIG. 1, the present invention provides a fixing member (corresponding to the moving heated body 1) that can circulate and rotate and has at least the electromagnetic induction heating layer 2, and the fixing member is locally in the heating region A fixing device including a heating device 3 having an exciting coil 4 that is heated by electromagnetic induction, and a movement detecting means 5 for detecting a moving state of the fixing member, and two different positions with respect to the moving direction of the fixing member. Temperature detection means 6 for detecting the temperature, and each detection information from the movement detection means 5 and the temperature detection means 6Is used to calculate the amount of power supplied to the exciting coil 4 when the detected information is within a predetermined allowable range.And a supply power control means 7 for controlling the supply power to the excitation coil 4 of the heating device 3.
[0015]
  The present invention is also directed to an image recording apparatus using an electromagnetic induction heating device.
  In this case, as shown in FIG. 1, the present invention includes an image carrying carrier (corresponding to the moving heated body 1) having at least an electromagnetic induction heat generating layer 2 and carrying and carrying an unfixed image, and the image carrying A heating device 3 having an excitation coil 4 in which the carrier is locally heated by electromagnetic induction, and a position downstream of the portion of the image carrier that faces the heater 3 and melted on the image carrier In an image recording apparatus provided with a pressure fixing member that at least presses and transfers an unfixed image onto a recording material, a movement detecting means 5 for detecting the movement state of the image carrier and the movement of the image carrier Temperature detection means 6 for detecting two different temperatures with respect to the direction, and each detection information from the movement detection means 5 and the temperature detection means 6Is used to calculate the amount of power supplied to the exciting coil 4 when the detected information is within a predetermined allowable range.And a supply power control means 7 for controlling the supply power to the excitation coil 4 of the heating device 3.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1
FIG. 2 shows a first embodiment of a fixing device using an electromagnetic induction heating device according to the present invention.
In the figure, a fixing device 20 according to the present embodiment stretches a fixing belt 30 between a pair of stretching rolls 21 and 22 so as to be able to circulate and rotate, and uses one stretching roll 21 as a driving roll in the direction of an arrow. A pressure roll 23 is disposed in pressure contact with the fixing belt 30 using the other tension roll 22 as a backup roll, and a fixing nip between the pressure roll 23 and the backup roll 22 in the fixing belt 30. An area is formed as a fixing area Y, and a portion of the fixing belt 30 located on the upstream side of the fixing area Y is formed as a heating area X by the heating device 40.
[0017]
In the present embodiment, as the fixing belt 30, for example, as shown in FIG. 3, a base layer 30a made of a sheet member having high heat resistance, and an electromagnetic induction heating layer (conductive layer) 30b laminated thereon, It is preferable to basically include three layers including the uppermost surface release layer 30c.
Here, as the base layer 30a, a resin having high heat resistance typified by polyimide, polyamide, polyimide amide or the like is used. For example, a layer having a thickness of 20 to 80 μm is used.
Further, the electromagnetic induction heat generating layer 30b can be appropriately selected as long as it generates heat by electromagnetic induction heating action. In the present embodiment, for example, the thickness of the electromagnetic induction heat generating layer 30b is 1 μm to 20 μm. The specific resistance value is 2.7 × 10^-8A material that is made of an electrically conductive material having a resistance of Ωm or less and generates heat due to eddy current loss is used.
Examples of the electromagnetic induction heat generating layer 30b in the present embodiment include copper, silver, aluminum, or a heat-resistant organic conductor corresponding thereto.
In particular, copper is optimal in view of the specific resistance value, thermal efficiency, ease of manufacture as the electromagnetic induction heating layer 30b (ease of etching processing, etc.), and cost.
[0018]
Further, the surface release layer 30c is preferably a highly releasable sheet or coat layer. For example, fluororesin, silicone resin, fluorosilicone rubber, fluororubber, silicone rubber, PFA, PTFE, FEP, etc. are used. It is done. In particular, when the material of the surface release layer 30c is made of an elastic material, it is preferable in that the image is less deteriorated and the image gloss is uniform because it adheres in such a state as to enclose the toner.
An intermediate layer (not shown) such as an elastic layer or a resistance adjustment layer may be interposed between the surface release layer 30c and the electromagnetic induction heat generating layer 30b.
[0019]
In addition, the heating device 40 is for causing the fixing belt 30 to be a moving heated body and causing the fixing belt 30 to generate electromagnetic induction heat in the heating region X.
In the present embodiment, for example, as shown in FIGS. 2 and 3, the heating device 40 is disposed inside the fixing belt 30 and is disposed along the width direction orthogonal to the conveying direction of the fixing belt 30. A non-magnetic long plate-like pedestal 41, a magnetic core 42 such as ferrite disposed in the center of a recess formed in the pedestal 41, and a fixing belt wound around the magnetic core 42 And an exciting coil 43 that generates a variable magnetic field H in the thickness direction of 30. When the power source 44 supplies power to the exciting coil 43, the electromagnetic induction heat generating layer 30b of the fixing belt 30 penetrates the thickness direction. A fluctuating magnetic field H is generated, an eddy current Ic is generated in the electromagnetic induction heat generating layer 30b, and the electromagnetic induction heat generating layer 30b is heated.
[0020]
Furthermore, in the present embodiment, a speed sensor 50 is disposed at a location corresponding to the upstream portion immediately before the drive roll 21 in the fixing belt 30.
The speed sensor 50 is constituted by an optical sensor, for example, and detects the speed of the fixing belt 30 by optically detecting a marker (ladder mark or hole) attached to the fixing belt 30. ing.
[0021]
On the other hand, in the present embodiment, temperature sensors 51 and 52 are disposed corresponding to immediately before and immediately after the heating region X of the fixing belt 30.
As the temperature sensors 51 and 52, a non-contact type temperature sensor (for example, an infrared radiation type sensor) disposed in a non-contact manner outside the fixing belt 30 is used.
In particular, in the present embodiment, paying attention to the fact that the amount of power supplied can be calculated by the temperature difference immediately before and after the heating region X and the heat capacity of the heating region X, temperature information from the temperature sensors 51 and 52 is obtained. Is used to calculate the amount of power supplied.
[0022]
Further, in the present embodiment, the control device 60 takes in detection signals from the speed sensor 50 and the temperature sensors 51 and 52, performs control of power supplied to the excitation coil 43 as shown in FIG. A predetermined control signal is sent to the power source 44 of the apparatus.
In addition to the control process shown in FIG. 4, the control device 60 synchronizes with a variety of control processes, for example, a drive control process for the fixing belt 30, specifically, a start signal from a start switch for image formation. The drive motor 21a is driven at a predetermined timing, and the fixing belt 30 is driven and rotated through a drive roll 21 connected to the drive motor 21a.
[0023]
Next, the operation of the fixing device according to the present embodiment will be described.
Now, in the image forming apparatus incorporating the fixing device according to the present embodiment, when a start switch (not shown) is turned on, the control device 60 starts driving the drive motor 21a at a predetermined timing to drive the fixing belt 30. Rotate.
In this state, the control device 60 executes a power supply control process for the exciting coil shown in FIG.
Then, under the condition that the fixing belt 30 is rotating normally without deterioration or the like, the control device 60 performs normal mode processing described later, sends a predetermined control signal to the power supply 44 of the heating device 40, and excites the heating device 40. A predetermined power is supplied to the coil 43.
Then, since the heating device 40 electromagnetically heats the fixing belt 30, the fixing belt 30 is locally heated in the heating region X, and the heated fixing belt 30 moves to the fixing region Y.
On the other hand, for example, the recording sheet 26 carrying the unfixed toner image 27 is conveyed to the fixing region Y at a predetermined timing, so that the pressure roller 23 and the heated fixing belt 30 are used to move the recording sheet 26 on the recording sheet 26. The unfixed toner image is fixed by heating and pressure.
[0024]
Here, the power supply control process to the exciting coil shown in FIG. 4 will be described in detail.
In FIG. 4, the control device 60 performs a speed check of the fixing belt 30 that is a moving heated body.
In this speed check, as shown in FIG. 5, the speed sensor 50 always detects the speed of the fixing belt 30 and first checks whether or not a detection signal is output. If there is a detection signal output, it is checked whether or not the speed detection value is an abnormal value.
If the detected speed value is an abnormal value, the mode is shifted to an abnormal mode. If the detected value is not an abnormal value, it is checked whether the detected speed value is within the allowable range. If it is out of the allowable range, a conveyance error and life warning of the fixing belt 30 are given.
[0025]
In FIG. 4, the control device 60 checks the temperature of the fixing belt 30 that is a moving body to be heated.
In this temperature check, as shown in FIG. 6, the temperatures around the heating region X of the fixing belt 30 are always detected by the temperature sensors 51 and 52. First, the presence / absence of a detection signal output is checked, and the detection signal output is not performed. If there is a detection signal output, it immediately checks whether the detected temperature value is an abnormal value.
If the detected temperature value is an abnormal value, the mode shifts to the abnormal mode. If the detected temperature value is not an abnormal value, it is checked whether the detected temperature value is within the allowable range. If it is out of the allowable range, a heating error and a life warning of the fixing belt 30 are given.
[0026]
Thereafter, the control device 60 performs the abnormal mode process or the normal mode process based on the speed check and the temperature check.
Here, as the abnormal mode processing, as shown in FIG. 7A, after the power supply to the exciting coil 43 is cut off, a detection sensor error or a system error warning is performed.
On the other hand, as the normal mode process, as shown in FIG. 7B, an optimum supply electric energy is calculated from the speed detection value, the temperature detection value, and the heat capacity of the fixing belt 30 selected in advance.
In particular, in this example, a temperature change in the heating region X is predicted by detecting the temperature before and after the heating region X in the fixing belt 30, and the supply power is calculated based on this.
When the calculation of the power supply amount is completed, preparation for power supply to the excitation coil 43 is performed, and then power supply to the excitation coil 43 is started.
[0027]
In such an operation process, for example, assuming a situation in which the fixing belt 30 suddenly stops, the abnormal mode processing is performed immediately since the mode is changed to the abnormal mode by checking the speed of the fixing belt 30, and the heating device The heating operation by 40 is stopped.
For this reason, in the heating region X, the stopped fixing belt 30 does not generate electromagnetic induction heat by the heating device 40, and a situation in which the fixing belt 30 abnormally increases in temperature is effectively avoided.
[0028]
Further, assuming a situation where the electromagnetic induction heat generating layer 30 b of the fixing belt 30 is deteriorated, the state of the fixing belt 30 is grasped by checking the temperature of the fixing belt 30.
For example, when the degree of deterioration of the fixing belt 30 is still mild, a heating error and a life warning of the fixing belt 30 are issued, while when the degree of deterioration of the fixing belt 30 is severe enough to require replacement. Shifts to the abnormal mode, and the abnormal mode processing is performed.
These operation processes are supported by, for example, embodiments described later.
[0029]
Further, the power supply control to the excitation coil 43 is not limited to the above-described one, and the amount of power supplied may be checked to further improve safety.
For example, the normal mode process may be constructed as shown in FIG. 8 in the process of controlling the power supplied to the exciting coil 43 in FIG.
That is, as shown in FIG. 8, the power supplied to the exciting coil 43 (specifically, the current value) is detected, and whether or not the detected value is within the allowable range is checked. On the other hand, if the power supply to the coil is continued, if it is out of the allowable range, a heating error of the fixing belt 30 and a life warning are given, and then an abnormal mode process is performed.
[0030]
Further, for example, the normal mode process may be constructed as shown in FIG. 9 in the process of controlling the power supplied to the exciting coil 43 in FIG.
That is, as shown in FIG. 9, the optimum supply power amount is calculated from the speed detection value, the temperature detection value, and the heat capacity of the fixing belt 30 selected in advance, and the calculated supply power is stored in the memory. Then, it is checked whether or not the supplied power is abnormal.
If the calculated power supply is abnormal, a heating error and a life warning of the fixing belt 30 are given, and then an abnormal mode process is executed.
On the other hand, if the calculated supply power is not abnormal, preparation for power supply to the excitation coil 43 is performed, and then power supply to the excitation coil 43 is started.
[0031]
Embodiment 2
FIG. 10 shows Embodiment 2 of the fixing device using the electromagnetic induction heating device according to the present invention.
In the figure, the fixing device 20 has a tube-shaped fixing belt 71 and a pressure roll 72 arranged in pressure contact with each other, and the fixing belt 71 corresponding to the fixing nip region between the fixing belt 71 and the pressure roll 72 is elastic. A pad 73 (a mode in which an elastic layer 73b is provided on a support holder 73a having a small heat capacity) is disposed.
In the present embodiment, the pressure roll 72 is driven by a driving source (not shown), and the fixing belt 71 is driven to rotate by the driving force from the pressure roll 72.
Reference numeral 75 denotes a metal roll attached to the surface of the pressure roll 72, which maintains a uniform axial temperature of the pressure roll 72 and functions as a cleaning member for cleaning the surface of the pressure roll 72. It has become.
[0032]
In the present embodiment, the fixing belt 71 basically includes three layers, a base layer, an electromagnetic induction heat generating layer, and a surface release layer, as in the fixing belt 30 of the first embodiment.
Further, a heating device 80 for causing the fixing belt 71 to generate heat by electromagnetic induction is disposed outside a portion of the fixing belt 71 opposite to the fixing nip region.
In the present embodiment, as shown in FIG. 10, the heating device 80 is disposed outside the fixing belt 71 with a shape corresponding to the curved shape of the fixing belt 71, and is orthogonal to the conveyance direction of the fixing belt 71. A non-magnetic long plate-like pedestal 81 disposed along the width direction, a magnetic core 82 such as ferrite disposed in the center of a recess formed in the pedestal 81, and the magnetic core 82 And an exciting coil 83 that generates a variable magnetic field in the thickness direction of the fixing belt 71. By supplying power to the exciting coil 83 with a power source (not shown), an electromagnetic induction heating layer of the fixing belt 71 is provided. A fluctuating magnetic field is generated so as to penetrate the thickness direction, an eddy current is generated in the electromagnetic induction heating layer, and the electromagnetic induction heating layer is heated.
Reference numeral 85 denotes a magnetic field shielding plate that shields a magnetic field toward the outside of the pedestal 81.
[0033]
Further, in the present embodiment, a speed sensor 90 is disposed on the upstream side of the fixing nip region in the periphery of the fixing belt 71, and the temperature sensors 91 and 98 are provided before and after the heating region by the heating device 80. 92, and the outputs of these sensors 90 to 92 are taken into a control device (not shown) and correspond to, for example, FIG. 4 (FIGS. 5 to 7) or a modified form thereof (FIGS. 8 and 9). Supply power control processing for the exciting coil is performed, and a predetermined control signal is sent to the power supply (not shown) of the heating device 80.
[0034]
Next, the operation of the fixing device according to the present embodiment will be described.
In FIG. 10, when a start switch (not shown) is turned on, the pressure roll 72 is driven and rotated at a predetermined timing, and the fixing belt 71 is rotated following the rotation.
At this time, the power supply control process to the exciting coil as shown in FIG. 4 is performed, and the normal mode process is performed under the condition that the fixing belt 71 is rotating normally without deterioration and the fixing belt 71 is heated. After the electromagnetic induction heating is locally performed by the apparatus 80, the recording sheet 26 moves to the fixing nip area, and on the other hand, the recording sheet 26 carrying the unfixed toner image 27 is also conveyed to the fixing nip area at a predetermined timing. A predetermined fixing operation by heat and pressure is performed in the area.
[0035]
In such an operation process, since the speed check by the speed sensor 90 and the temperature check by the temperature sensors 91 and 92 are performed in parallel, if the speed check or the temperature check shifts to the abnormal mode, immediately Abnormal mode processing is performed.
Therefore, for example, when the fixing belt 71 is stopped for some reason, an abnormal mode process (in this example, the power supplied to the exciting coil 83 is cut off) is performed immediately because the temperature check makes a transition to the abnormal mode. In addition, problems such as abnormal heating of the fixing belt 71 are effectively avoided.
Even when the fixing belt 71 is deteriorated, an abnormal mode process is performed or a predetermined warning is displayed according to the degree of the deterioration.
[0036]
Embodiment 3
FIG. 11 shows Embodiment 3 of an image recording apparatus using an electromagnetic induction heating device according to the present invention.
In the figure, the image recording apparatus includes an intermediate transfer belt 100 that is stretched over two stretching rolls 101 and 102 and whose peripheral surface moves around, for example, at a position facing the intermediate transfer belt 100. Four image forming units 110 (110Y, 110M, 110C, and 110K) that respectively form yellow, magenta, cyan, and black toner images are disposed.
Here, each of the image forming units 110 (110Y to 110K) includes, for example, a photosensitive drum 111 on which an electrostatic latent image is formed, a charging device 112 that charges the surface of the photosensitive drum 111 substantially uniformly, and a photosensitive An exposure device 113 that forms a latent image by irradiating a laser beam on the body drum 111 and a developing device 114 that selectively transfers toner to the latent image on the photoreceptor drum 111 to form a toner image are provided. Yes.
Reference numeral 115 is disposed so as to face the photosensitive drum 111 with the intermediate transfer belt 100 interposed therebetween, and an opposing roll 116 that forms a predetermined transfer nip area between the photosensitive drum 111 and the intermediate transfer belt 100. A bias roll 117 for applying a transfer bias for primary transfer of each color toner image on the photosensitive drum 111 to the intermediate transfer belt 100 via the intermediate transfer belt 100 is a transfer bias power source.
[0037]
Furthermore, in the present embodiment, the image recording apparatus heats the intermediate transfer belt 100 capable of generating heat, and heats the intermediate transfer belt 100 in the heating area X in front of the transfer and fixing area Z (the stretch roll 101 portion in this example). And a pressing and fixing roll 130 that presses the intermediate transfer belt 100 so as to be opposed to the stretching roll 101 in the transfer and fixing region Z of the intermediate transfer belt 100.
Here, as shown in FIG. 11, for example, the intermediate transfer belt 100 includes a base layer 100a made of a resin having high heat resistance such as polyimide, polyamide, and polyimideamide, and an electromagnetic induction heating layer (conductive layer) laminated thereon. Basically, there are three layers, that is, 100b and a surface release layer 100c such as a fluororesin or silicone resin having the highest mold release property as the uppermost layer.
In this embodiment, the electromagnetic induction heat generating layer 100b is partly exposed on the base layer 100a side so that the bias roll 116 and the electromagnetic induction heat generating layer 100b of the intermediate transfer belt 100 are always in contact with each other. It has become.
[0038]
Further, the heating device 120 is disposed inside the intermediate transfer belt 100 in substantially the same manner as in the first embodiment, and is disposed along the width direction orthogonal to the conveyance direction of the intermediate transfer belt 100. A long plate-like pedestal (not shown), a magnetic core (not shown) such as ferrite disposed in the center of a recess formed in the pedestal, and wound around the magnetic core An excitation coil (not shown) that generates a variable magnetic field in the thickness direction of the intermediate transfer belt 100 is provided, and a variable magnetic field is generated by supplying power to the excitation coil by a power supply 124. An eddy current is generated in the induction heat generating layer 100b, and the electromagnetic induction heat generating layer 100b is heated.
[0039]
Further, in such an image recording apparatus, in the present embodiment, for example, a speed sensor 140 is disposed inside the intermediate transfer belt 100, and the temperature sensor 141 is provided before and after the heating region of the intermediate transfer belt 100 by the heating device 120. , 142 are arranged. The outputs of these sensors 140 to 142 are taken into a control device (not shown), and the power supply control process to the excitation coil corresponding to FIG. 4 (FIGS. 5 to 7) or a modified form thereof (FIGS. 8 and 9) is performed. The predetermined control signal is sent to the power supply 124 of the heating device 120.
[0040]
Next, the operation of the image recording apparatus according to this embodiment will be described.
As shown in FIG. 11, toner images of different colors are formed on the photosensitive drum 111 by the image forming units 110 (110Y to 110K).
On the other hand, the intermediate transfer belt 100 circulates in a certain direction, and a primary bias from the bias roll 116 acts on the primary transfer portion of each image forming unit 110 so that the toner image on the photosensitive drum 111 is transferred to the intermediate transfer belt. 100 is transferred.
After the toner images are sequentially transferred from the four image forming units 110, the superimposed four color toner images T are conveyed to the heating region X facing the heating device 120 by the movement of the intermediate transfer belt 100.
[0041]
In this heating region X, the four color toner images on the intermediate transfer belt 100 are melted by the heat generation of the electromagnetic induction heat generating layer 100b by electromagnetic induction heating.
Thereafter, the melted toner image T is brought into pressure contact with the recording sheet 26 at room temperature by the pressing action of the pressure fixing roll 130 in the transfer fixing region Z, and the toner image T penetrates the recording sheet 26 and is transferred and fixed. The image T is cooled while being conveyed toward the exit side of the fixing nip area. At the exit of the fixing nip region, the toner temperature is sufficiently low and the toner cohesive force is large, so that the toner image is transferred and fixed almost completely onto the recording sheet 26 without causing an offset.
[0042]
In such an operation process, since the speed check by the speed sensor 140 and the temperature check by the temperature sensors 141 and 142 are performed in parallel, if the speed check or the temperature check shifts to the abnormal mode, immediately Abnormal mode processing is performed.
Therefore, for example, when the intermediate transfer belt 100 is stopped for some reason, an abnormal mode process (in this example, the power supplied to the exciting coil is cut off) is immediately executed because the temperature check makes a transition to the abnormal mode. In addition, problems such as abnormal temperature rise of the intermediate transfer belt 100 are effectively avoided.
Even when the intermediate transfer belt 100 is deteriorated, abnormal mode processing is performed or a predetermined warning is displayed according to the degree of deterioration.
[0043]
【Example】
Example 1
In this example, the fixing device model according to the first embodiment is embodied. The power supplied to the exciting coil 43 is 100 to 1000 W, and the peripheral speed of the fixing belt 30 is 70 to 200 mm / sec.
The power supply 44 for supplying power to the exciting coil 43 is a high-frequency inverter power supply, and the AC frequency is 20 to 100 kHz.
Further, the fixing belt 30 used in this example has a structure as shown in FIG. 3, a polyimide base layer 30 a having a thickness of 20 to 80 μm, a copper electromagnetic induction heating layer 30 b having a thickness of 1 to 20 μm, and 10 to 50 μm. The surface release layer 30c is formed so as to have a total thickness of about 100 μm.
Moreover, the speed sensor 50 and the temperature sensors 51 and 52 employ | adopted the optical sensor and infrared radiation | emission type | mold sensor which can measure without contact, respectively.
[0044]
The following experiment was conducted on the fixing device having the above configuration.
This experiment was carried out continuously for a total of 12 hours, and the experiment for a total of 12 hours was repeated several tens of times in order to confirm the reliability.
(1) Continuous fixing operation
(2) Fixing operation every 5 or 10 seconds
(3) Conditions for reducing or stopping the speed of the fixing belt by applying a load to the fixing belt during the states of (1) and (2)
(4) Conditions for driving in the state of (1) and (2) by damaging the fixing belt
(5) Conditions for supplying electric power that is larger or smaller (outside the allowable range) than the amount of electric power to be supplied
(6) Conditions for the speed sensor 50 and the temperature sensors 51 and 52 to output values different from the measured values
[0045]
In this experiment, speed and temperature sensor failure tests are initially performed in advance, and it is confirmed that the control system is operating normally.
As a result of the above experiment, the fixing device was secured in all conditions, and the phenomenon that caused the fire (ignition, smoke, etc.) could be prevented.
Further, no abnormality of the fixing device due to the influence after this experiment was observed, and normal operation was possible after that, and the runaway of the fixing belt 30 (moving heated object) resulting in thermal damage destruction occurred. It was possible to make it a safe device.
[0046]
【The invention's effect】
As described above, according to the electromagnetic induction heating device according to the present invention, the movement information and temperature information of the moving object to be heated are detected, and the supply power control to the excitation coil of the heating device is performed based on each detection information. Therefore, the situation (movement, temperature) of the moving object to be heated can be accurately grasped, and supply power control can be realized safely.
For this reason, it is possible to prevent thermal runaway of the moving heated object, effectively preventing thermal damage and thermal destruction of the apparatus, and providing a highly safe and reliable apparatus.
Further, according to the fixing device and the image recording device using such an electromagnetic induction heating device, it is possible to prevent thermal runaway of the moving heated object, so that the fixing operation using the moving heated object or The image recording operation can be realized safely and reliably.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing an outline of an electromagnetic induction heating device according to the present invention.
FIG. 2 is an explanatory diagram illustrating an overall configuration of the fixing device according to the first exemplary embodiment.
3 is an explanatory diagram illustrating a configuration example of a fixing belt and a heating device used in Embodiment 1. FIG.
FIG. 4 is a flowchart showing a processing example of power supply control to the exciting coil used in the first embodiment.
FIG. 5 is a flowchart showing a processing example of “speed check of moving object to be heated” in FIG. 4;
6 is a flowchart showing an example of a process of “temperature check of moving object to be heated” in FIG. 4;
7A is a flowchart showing an example of abnormal mode processing, and FIG. 7B is a flowchart showing an example of normal mode processing.
FIG. 8 is a flowchart showing another example of normal mode processing.
FIG. 9 is a flowchart showing still another example of normal mode processing.
FIG. 10 is an explanatory diagram illustrating an overall configuration of a fixing device according to a second embodiment.
FIG. 11 is an explanatory diagram illustrating an overall configuration of an image recording apparatus according to a third embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Moving body to be heated, 2 ... Electromagnetic induction heat generating layer, 3 ... Heating device, 4 ... Excitation coil, 5 ... Movement detection means, 6 ... Temperature detection means, 7 ... Supply power control means, 8 ... Abnormality diagnosis means, 9 ... Mode switching means

Claims

An electromagnetic induction heating apparatus comprising a movable object to be moved and having at least an electromagnetic induction heat generating layer, and a heating device having an excitation coil in which the movable object is locally heated by electromagnetic induction in a heating region. There,
A movement detecting means for detecting a moving state of the moving heated body;
Temperature detecting means for detecting two different temperatures with respect to the moving direction of the moving heated body;
Using each detection information from the movement detection means and the temperature detection means, when each detection information is within a predetermined allowable range, the amount of power supplied to the exciting coil is calculated, and heating is performed based on the calculated power supply amount. An electromagnetic induction heating apparatus comprising: a supply power control means for controlling power supplied to an excitation coil of the apparatus.

In the electromagnetic induction heating device according to claim 1,
The electromagnetic induction heating apparatus, wherein the movement detection means is speed detection means for detecting the speed of the moving object to be heated.

In the electromagnetic induction heating device according to claim 1,
The supply power control means includes an abnormality diagnosis means for diagnosing that the state of the moving heated body is abnormal under the condition that the detection information from the movement detection means and the temperature detection means deviates from the allowable condition;
And a mode switching means for switching the power supply control to the exciting coil of the heating device from the normal mode to the abnormal mode under the condition that the abnormality diagnosing means diagnoses that the state of the moving heated object is abnormal. Electromagnetic induction heating device.

The electromagnetic induction heating device according to claim 3,
Electromagnetic induction characterized in that the abnormality diagnosis means diagnoses that the heat generation state of the moving heated body is abnormal under the condition that the moving heated body is detected to be stopped by at least the movement detecting means Heating device.

The electromagnetic induction heating device according to claim 3,
An electromagnetic induction heating apparatus characterized in that the mode switching means executes an abnormal mode in which power supply to the exciting coil of the heating apparatus is cut off based on an abnormality diagnosis by the abnormality diagnosis means.

The electromagnetic induction heating device according to claim 3,
The abnormality diagnosis unit includes a supply power detection unit that detects supply power to the excitation coil of the heating device, and a supply power diagnosis unit that diagnoses whether the supply power detected by the supply power detection unit is appropriate. An electromagnetic induction heating device.

The electromagnetic induction heating device according to claim 3,
The abnormality diagnosis unit has a storage unit that stores the result of controlling the power supplied to the excitation coil of the heating device based on each detection information detected by the movement detection unit and the temperature detection unit,
An electromagnetic induction heating apparatus comprising a supply power diagnosis function unit that performs an appropriate diagnosis of supply power control based on a control result of supply power stored in the storage unit.

In the electromagnetic induction heating device according to claim 1,
An electromagnetic induction heating apparatus using detection information from a movement detection means and a temperature detection means as control information other than supply power control.

A fixing device comprising a fixing member capable of circulating rotation and having at least an electromagnetic induction heat generating layer, and a heating device having an excitation coil in which the fixing member is locally heated by electromagnetic induction in a heating region,
A movement detecting means for detecting a movement state of the fixing member;
Temperature detecting means for detecting two different temperatures with respect to the moving direction of the fixing member;
Using each detection information from the movement detection means and the temperature detection means, when each detection information is within a predetermined allowable range, the amount of power supplied to the exciting coil is calculated, and heating is performed based on the calculated power supply amount. A fixing device comprising: a power supply control means for controlling power supplied to an excitation coil of the device.

An image carrier having at least an electromagnetic induction heating layer and carrying an unfixed image thereon, a heating device having an excitation coil in which the image carrier is locally electromagnetically heated, and the image carrier An image recording apparatus comprising: a pressing and fixing member disposed at a downstream position of a portion facing the heating device and configured to press and transfer and fix an unfixed image melted on the image carrier on the recording material. ,
A movement detecting means for detecting a moving state of the image carrier;
Temperature detecting means for detecting two different temperatures with respect to the moving direction of the image carrier;
Using each detection information from the movement detection means and the temperature detection means, when each detection information is within a predetermined allowable range, the amount of power supplied to the exciting coil is calculated, and heating is performed based on the calculated power supply amount. An image recording apparatus comprising: supply power control means for controlling power supplied to an excitation coil of the apparatus.